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A role for decorin in cutaneous wound healing and angiogenesis   总被引:2,自引:0,他引:2  
Decorin is known to influence tissue tensile strength and cellular phenotype. Therefore, decorin is likely to have an impact on tissue repair, including cutaneous wound healing. In this study, cutaneous healing of both excisional and incisional full‐thickness dermal wounds was studied in decorin‐deficient (Dcn?/?) animals. A statistically significant delay in excisional wound healing in the Dcn?/? mice occurred at 4 and 10 days postwounding and, in incisional wounds at 4, 10, and 18 days when compared with wild‐type (Dcn?/?) controls. Fibrovascular invasion into polyvinylalcohol sponges was significantly increased by day 18 in Dcn?/? mice relative to Dcn+/+ mice. The 18‐day sponge implants in the Dcn?/? mice showed a marked accumulation of biglycan when compared with the corresponding implants in Dcn+/+ mice. Thus, regulated production of decorin may serve as an excellent therapeutic approach for modifying impaired wound healing and harmful foreign body reactions.  相似文献   
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Effects of endothelin-1 on epithelial ion transport in human airways   总被引:1,自引:0,他引:1  
Endothelin-1 (ET-1) exerts many biological effects in airways, including bronchoconstriction, airway mucus secretion, cell proliferation, and inflammation. We investigated the effect of ET-1 on Na absorption and Cl secretion in human bronchial epithelial cells. Addition of 10(-7) M ET-1 had no effect on the inhibition of the short circuit current (Isc) induced by amiloride, a Na channel blocker. Addition of 10(-7) M ET-1 to the apical bath in the presence of amiloride increased Isc in cultured human bronchial epithelial cells studied in Ussing chambers. No effect was observed when ET-1 was added to basolateral bath, indicating that the involved ET-1 receptors are likely present only in the apical membrane of the cells. Use of Cl-free solutions and bumetanide reduced the ET-1-induced increases in Isc, indicating that ET-1 stimulates Cl secretion. The ET-1-induced increase in Isc was prevented by exposure to the ETB receptor antagonist BQ-788 but not to the ETA receptor antagonist BQ-123. ET-1 did not raise intracellular Ca levels, but increased the intracellular concentration of cAMP. These findings indicate that ET-1 is a Cl secretagogue in human airways and acts presumably through apically located ETB receptors and activation of the cAMP pathway.  相似文献   
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An enzyme immunoassay (EIA) for serum antibodies to human immunodeficiency virus type 1 (HIV-1), based on the synthetic pentadecapeptide SGKLICT-TAVPWNAS, a segment of the transmembrane glycoprotein (gp41) of the virus, was developed and tested for sensitivity and specificity. Sera of 152 individuals at various stages of HIV-1 infection, including two prospectively and six retrospectively studied patients exposed to HIV-1 but seronegative on initial testing in whole-virus EIA and immunoblotting, were screened with the gp41 peptide antibody EIA. The reference population consisted of 1,000 healthy HIV-1 antibody-negative blood donors. In addition, five individuals with antibodies to HIV-2 were studied. Antibodies to the synthetic peptide were detected in 100% of those with asymptomatic infection. Only one patient with LAS failed to react in the peptide EIA. Patients with HIV-2 infection did not react in this test. The peptide antibodies appeared rapidly after infection, were detectable at the time when seroconversion was observed by immunoblotting, and preceded reactivity in whole-virus EIA. Sera of seven patients with verified HIV-1 infection did not react with gp41 in immunoblotting, although antibodies were readily detectable in the gp41 peptide EIA.  相似文献   
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Familial amyloidosis, Finnish type (FAF) (gelsolin-related amyloidosis) is an autosomal dominant form of systemic amyloidosis characterized by corneal lattice dystrophy and peripheral polyneuropathy. The accumulating protein in FAF consists of fragments of gelsolin, an actin-modulating protein. The gelsolin mutation G654A has been found in both Finnish and Japanese patients. To study the origin of the gelsolin mutation in these patients we performed haplotype analysis in 10 Finnish and 2 Japanese FAF families. Poymorphic DNA markers GSN, D9S103, AFMa061xd9, and AFMa139xb9 revealed a uniform disease haplotype in all the disease-associated chromosomes of the Finnish FAF families, which was different from the one observed in the Japanese families. The present results and the previously detected gelsolin mutation G654T in Czech and Danish FAF patients suggest that nucle otide 654 may represent a mutation hot spot in the gelsolin gene. The DNA markers studied here will be useful in future genealogical analyses of FAF. © 1995 Wiley-Liss, Inc.  相似文献   
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BACKGROUND: The aim of the European Sero-Epidemiology Network (ESEN2) is to harmonise the serological surveillance of vaccine-preventable diseases in Europe. OBJECTIVE: To allow comparison of antibody prevalence in different countries by standardising results into common units. STUDY DESIGN: For varicella zoster virus (VZV), a reference laboratory established a panel of 148 samples, characterised by indirect enzyme-immunoassay (ELISA), indirect immunofluorescence, and complement fixation test. Fifty-seven samples were also studied by the fluorescence antibody to membrane antigen test. The geometric mean of the antibody activity (GMAA) obtained from four ELISA determinations was used to characterise each sample of the panel as positive (GMAA: >100 mIU/ml), equivocal (GMAA: 50-100 mIU/ml) or negative (GMAA: <50 mIU/ml) for antibody to VZV (anti-VZV). Thirteen laboratories, using five different ELISA tests, tested the panel. RESULTS: Agreement with the reference laboratory was above 85% in all cases, and the R(2) values obtained from regression analysis of the quantitative results were always higher than 0.87. Finally, the regression equations could be used to convert national values into a common unitage. CONCLUSION: This study confirmed that results for anti-VZV obtained by different ELISA methods can be converted into common units, enabling the comparison of the seroprevalence profiles obtained in the participant countries.  相似文献   
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