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Juli Busquets Jose Castellote Jaume Torras Juan Fabregat Emilio Ramos Laura Llado Antonio Rafecas Esmeralda de la Banda Juan Figueras 《Journal of gastrointestinal surgery》2007,11(4):458-463
Background Cold ischemia time and the presence of postoperative hepatic arterial thrombosis have been associated with biliary complications
(BC) after liver transplantation. An ABO-incompatible blood group has also been suggested as a factor for predisposal towards
BC. However, the influence of Rh nonidentity has not been studied previously.
Materials Three hundred fifty six liver transplants were performed from 1995 to 2000 at our hospital. BC incidence and risk factors
were studied in 345 patients.
Results Seventy patients (20%) presented BC after liver transplantation. Bile leakage (24/45%) and stenotic anastomosis (21/30%) were
the most frequent complications. Presence of BC in Rh-nonidentical graft–host cases (23/76, 30%) was higher than in Rh-identical
grafts (47/269, 17%) (P = 0.01). BC was also more frequent in grafts with arterial thrombosis (9/25, 36% vs 60/319, 19%; P = 0.03) and grafts with cold ischemia time longer than 430 min (26/174, 15% vs 44/171, 26%; P = 0.01). Multivariate logistic regression confirmed that Rh graft–host nonidentical blood groups [RR = 2(1.1–3.6); P = 0.02], arterial thrombosis [RR = 2.6(1.1–6.4); P = 0.02] and cold ischemia time longer than 430 min [RR = 1.8(1–3.2); P = 0.02] were risk factors for presenting BC.
Conclusion Liver transplantation using Rh graft–host nonidentical blood groups leads to a greater incidence of BC. 相似文献
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Laura Cisneros Maria-Carlota Londo?o Carmen Blasco Ramón Bataller Rosa Miquel Miquel Bruguera Pere Ginès Antoni Rimola 《Liver transplantation》2007,13(7):1017-1027
The pathogenic mechanisms of accelerated graft fibrosis in hepatitis C recurrence after liver transplantation (LT) are not well established. The aim of the study was to assess whether a greater activation of hepatic stellate cells (HSC), the major collagen-producing cells in the liver, can occur in these patients as compared to non-LT patients with chronic hepatitis C. We determined the amount of activated HSC by computer-based morphometric analysis of alpha-smooth muscle actin (alphaSMA)-positive cells and the hepatic TGFbeta(1) expression by immunohistochemistry in 46 LT patients with hepatitis C recurrence, 35 non-LT patients with chronic hepatitis C, and 16 controls. Hepatic alphaSMA and TGFbeta(1) expression was higher in LT patients with hepatitis C recurrence than in controls and was correlated with fibrosis stage and progression rate. No significant difference in alphaSMA and TGFbeta(1) expression was observed between LT and non-LT patients with hepatitis C, with the exception of a higher transforming growth factor beta-1 (TGFbeta(1)) expression in non-LT patients in the early stages of fibrosis. LT patients receiving cyclosporine (CsA) or tacrolimus (FK) had a similar fibrosis progression rate and alphaSMA and TGFbeta(1) expression. In conclusion, the accelerated fibrosis observed in LT patients with hepatitis C recurrence does not seem to be related to a greater amount of activated HSC and TGFbeta(1) expression in the grafts of these patients as compared to non-LT patients with chronic hepatitis C. In LT patients, the amount of activated HSC and TGFbeta(1) expression correlated with fibrosis stage and progression, without any apparent influence of the type of calcineurin inhibitor administered. 相似文献
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Relaxin down-regulates renal fibroblast function and promotes matrix remodelling in vitro. 总被引:1,自引:0,他引:1
Rosemary Masterson Tim D Hewitson Kristen Kelynack Marina Martic Laura Parry Ross Bathgate Ian Darby Gavin Becker 《Nephrology, dialysis, transplantation》2004,19(3):544-552
BACKGROUND: Renal fibroblasts are important effector cells in tubulointerstitial fibrosis, with experimental antifibrotic strategies focusing on the functional down-regulation of these cells. Several experimental models of fibrosis have provided evidence for the effectiveness of the polypeptide hormone relaxin as a potential antifibrotic agent. This study was conducted to further elucidate the antifibrotic mechanisms of relaxin on renal fibroblasts in vitro. METHODS: Rat cortical fibroblasts were obtained from outgrowth culture of renal tissue isolated from kidneys 3 days post-unilateral ureteric obstruction and constituted 100% of cells studied. A relaxin radio-receptor assay was used to establish binding of relaxin to renal fibroblasts in vitro. Functional studies then examined the effects of H2 relaxin (0, 1, 10 and 100 ng/ml) on fibroblast kinetics, expression of alpha-smooth muscle actin (alpha-SMA), total collagen synthesis, collagenase production and collagen-I lattice contraction. CTGF mRNA expression was also measured by northern analysis. RESULTS: H2 relaxin bound with high affinity to rat renal fibroblasts, but receptor numbers were low. Consistent with its previously reported bimodal effect, transforming growth factor (TGF-beta 1) reduced fibroblast proliferation, an effect abrogated by H2 relaxin. Fibroblasts exposed to H2 relaxin (100 ng/ml) for 24 h demonstrated decreased immunostaining for alpha-SMA and reduced alpha-SMA protein expression compared with controls. There was a trend for a relaxin-mediated reduction in total collagen synthesis and alpha 1(I) mRNA expression with large dose-related increases in collagenase protein expression being observed. TGF-beta 1-stimulated collagen-I lattice contraction was significantly inhibited following co-incubation with 100 ng/ml relaxin. Incremental doses of H2 relaxin had no significant effect on CTGF mRNA expression. CONCLUSIONS: The findings of this study suggest that the antifibrotic effects of relaxin involve down-regulation of fibroblast activity, increase in collagenase synthesis and restructuring of collagen-I lattices, which are consistent with its known physiological role of matrix remodelling. Although there appears to be an interaction between TGF-beta 1 and H2 relaxin, this does not appear to involve a reduction in CTGF mRNA expression. 相似文献
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Reducing medical errors has become an international concern. Population-based studies from a number of nations around the world have consistently demonstrated unacceptably high rates of medical injury and preventable deaths. The introduction of effective reporting systems is a cornerstone of safe practice within hospitals and other healthcare organisations. Reporting can help to identify hazards and risks. However, reporting in itself does not improve safety. It is the response to reports that leads to change. Clinical teams must feel empowered to change the way in which they deliver their services, promoting effective clinical risk management. Process analysis, implementation of evidence-based practices, and a clear accountability system are effective tools not only for decreasing error rates, but also for improving effectiveness. Clinical Governance represents the context in which effective clinical risk management should be promoted and continuously improved. It should not be regarded as a separate activity, but should form part of the everyday practice of all healthcare professionals. It requires good multidisciplinary working and a willingness to reflect on and learn from errors to achieve a patient-centred and safer system. 相似文献