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Susan Yung Heinz Hausser Gareth Thomas Liliana Schaefer Hans Kresse Malcolm Davies 《Peritoneal dialysis international》2004,24(2):147-155
OBJECTIVE: Previous studies have shown that decorin and biglycan account for over 70% of the proteoglycans (PGs) synthesized by human peritoneal mesothelial cells (HPMCs). Since these PGs are involved in the control of cell growth, cell differentiation, and matrix assembly, we investigated their turnover in cultured HPMCs. METHODS: Confluent HPMCs were metabolically labeled with [35S]-sulfate and the labeled products isolated from the cell medium and the cell layer characterized by sensitivity to bacterial eliminases. Experiments were undertaken with exogenous labeled decorin, and its metabolic state was studied. RESULTS: In a 24-hour labeling period, 75% of the newly synthesized chondroitin sulfate/dermatan sulfate (CS/DS) PGs appeared in the culture medium, the majority of which (90%) was decorin. In the cell layer, protein-free glycosaminoglycan (GAG) chains accounted for 21% of the total CS/DS at 24 hours and exhibited constant specific activity at 12-16 hours. The latter material was turned over with a half-life of approximately 2.5 hours. Exogenous decorin underwent receptor-mediated endocytosis and subsequent intracellular degradation. Uptake but not degradation could be inhibited by heparin. CONCLUSIONS: HPMCs are distinguished by a rapid turnover of decorin. A characteristic metabolic feature is the existence of a large intracellular pool of protein-free DS-GAGs. Understanding the control of decorin turnover in HPMCs might lead to delineation of its potential role in both the physiology and pathophysiology of the membrane in PD patients. 相似文献
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Abstract The outcome of OLT for HBV-related liver disease is dependent on the prevention of allograft re-infection. Over the past decade, major advances have been made in the management of HBV transplant candidates. The advent of long-term hepatitis B immune globulin (HBIG) administration as a prophylaxis against HBV recurrence, and the introduction of new antiviral agents against HBV infection, such as lamivudine (LAM), were a major breakthrough in the management of these patients. Results of OLT for HBV infection are similar to those achieved with other indications. Pre-OLT antiviral treatment such as LAM can suppress HBV replication before OLT and thus decrease the risk of re-infection of the graft. Combination prophylaxis with LAM and HBIG after transplantation highly effectively reduces the rate of HBV re-infection, even in HBV replicative cirrhotic, patients. The optimal HBIG protocol in the LAM era is yet to be defined: dosing of HBIG, routes of administration, and possibility of stopping HBIG. Several antiviral drugs have been developed for the management of HBV infection on the graft, so outcome is currently good. 相似文献
15.
Roselind Lieb Petra Zimmermann Robert H Friis Michael H?fler Sven Tholen Hans Ulrich Wittchen 《European psychiatry》2002,17(6):321-331
OBJECTIVE: Although somatoform disorders are assumed to be chronic clinical conditions, epidemiological knowledge on their natural course based on representative samples is not available. METHOD: Data come from a prospective epidemiologic study of adolescents and young adults in Munich, Germany. Respondents' diagnoses (N = 2548) at baseline and follow-up on average 42 months later are considered. The follow-up incidence, stability as well as selected baseline risk factors (sociodemographics, psychopathology, trauma exposure) for the incidence and stability of somatoform disorders and syndromes are prospectively examined. Diagnostic information was assessed by using the standardized Munich-Composite International Diagnostic Interview (M-CIDI). RESULTS: Over the follow-up period, incidence rate for any of the covered somatoform diagnoses was 25.7%. Stability for the overall group of any somatoform disorder/syndrome was 48%. Female gender, lower social class, the experience of any substance use, anxiety and affective disorder as well as the experience of traumatic sexual and physical threat events predicted new onsets of somatoform conditions, while stability was predicted by being female, prior existing substance use, affective and eating disorders as well as the experience of a serious accident. CONCLUSIONS: At least for a substantial proportion of individuals, the overall picture of somatization seems to be relatively stable, but with fluctuation in the symptom picture over time. Being female, the experience of substance use as well as anxiety disorder seem to constitute risk factors for the onset of new somatoform conditions as well as for a stable course over time. 相似文献
16.
Repression is commonly assumed to be a major characteristic of the cancer-prone personality. Main supporting evidence includes studies showing that cancer patients are low in emotional expression and that repressives have shorter survival. The evidence did not seem compelling, mainly because of contrary findings, overlooking the age factor and the assessment instruments. Thus, we examined whether repression is a response to the threat posed by the cancer diagnosis and whether cancer patients are more repressive, using a new assessment method combining anxiety and defensiveness scores and controlling age. The subjects were 98 women comprising three groups comparable in demographic characteristics: (a) breast biopsy showed they were healthy (n = 40), (b) biopsy showed they had breast cancer (n = 32), and (c) underwent surgery unrelated to cancer (n = 26). Only post-surgery groups a and b knew the diagnosis. Questionnaires of information and repression were administered to all women pre- and post-surgery. Before surgery, the groups did not differ in repression, anxiety and defensiveness. Post-surgery, there were no differences in anxiety but MANOVA and X2 analyses showed that, in the malignancy group, defensiveness and the number of repressors increased more than in the other groups. The results indicate that repression could be a response to the threat posed by the cancer diagnosis and a means for keeping anxiety at a tolerable level rather than a personality trait of cancer patients. 相似文献
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Intramolecular Aminoalkylation of Amidoximes 2-tertiary aminobenzamidoximes 2 react with mercury edta by intramolecular aminoalkylation and oxidation to anellated quinazolinone-oximes 5 ; their configuration is not changed. 相似文献
19.
Hans C. Andersson Dilys M. Parry John J. Mulvihill 《American journal of medical genetics. Part A》1995,56(1):72-75
Hereditary lymphedemas that are not associated with other malformations usually affect the lower limbs and are inherited in an autosomal dominant fashion. These non-syndromic hereditary lymphedemas are categorized by their age of onset, being either congenital (Milroy disease) or having an onset in childhood or around puberty (Meige disease). We describe a family in which three individuals in three generations had unusually late onset of lym-phedema in their mid-twenties or thirties. The proband additionally developed a very rare lymphangiosarcoma. This tumor, usually associated with post-mastectomy lym-phedema, has not been described in late-onset hereditary lymphedema. Because of an unusually high incidence of multiple primary tumors in association with lymphangiosarcoma in the literature (approximately 10%) and the proband's own familial cancer background, we speculate that an inherited predisposition to malignancy may underlie the development of lymphedema-associated lymphangiosarcoma. © 1995 Wiley-Liss, Inc. 相似文献
20.
Mark Hans Emanuel M.D. Augustinus Hart M.Sc. Kees Wamsteker M.D. Frits Lammes M.D. 《Fertility and sterility》1997,68(5):881-886
Objective: To determine the contribution of several variables to fluid loss during transcervical resection of submucous myomas.Design: An observational study using multiple linear regression analyses.Setting: A university-affiliated training hospital and a university department of clinical epidemiology and biostatistics.Patient(s): Patients with submucous myomas.Intervention(s): Transcervical resection of submucous myomas and monitoring of fluid loss.Main Outcome Measure(s): Patient age, uterine enlargement, treatment with GnRH analogues or 8-ornithine-vasopressin, type of anesthesia, number of myomas, intramural extension of the myoma (type of myoma), and operating time were tested as variables.Result(s): Only intramural extension of the myoma and operating time were obviously related to fluid loss. For the other variables, such a relation was weak at best. The relation between fluid loss and operating time was not modified by any of the other variables.Conclusion(s): Because fluid loss is an important limiting factor in the transcervical resection of submucous myomas, special attention should be paid to reduction of the operating time and preoperative assessment of the intramural extension of the myoma to guide appropriate patient selection. 相似文献