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61.
Mineralocorticoid receptors (MRs) are classically known to be expressed in the distal collecting duct of the kidney. Recently it was reported that MR is identified in the heart and vasculature. Although MR expression is also found in the brain, it is restricted to the hippocampus and cerebral cortex under normal condition, and the role played by MRs in brain remodeling after cerebral ischemia remains unclear. In the present study, we used the mouse 20-min middle cerebral artery occlusion model to examine the time course of MR expression and activity in the ischemic brain. We found that MR-positive cells remarkably increased in the ischemic striatum, in which MR expression is not observed under normal conditions, during the acute and, especially, subacute phases after stroke and that the majority of MR-expressing cells were astrocytes that migrated to the ischemic core. Treatment with the MR antagonist spironolactone markedly suppressed superoxide production within the infarct area during this period. Quantitative real-time RT-PCR revealed that spironolactone stimulated the expression of neuroprotective or angiogenic factors, such as basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF), whereas immunohistochemical analysis showed astrocytes to be cells expressing bFGF and VEGF. Thereby the incidence of apoptosis was reduced. The up-regulated bFGF and VEGF expression also appeared to promote endogenous angiogenesis and blood flow within the infarct area and to increase the number of neuroblasts migrating toward the ischemic striatum. By these beneficial effects, the infarct volume was significantly reduced in spironolactone-treated mice. Spironolactone may thus provide therapeutic neuroprotective effects in the ischemic brain after stroke.  相似文献   
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Journal of Gastroenterology - Following liver transplantation (LT), allograft liver failure can be developed by various causes and requires re-LT. Hence, this study aimed to clarify the...  相似文献   
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Journal of Interventional Cardiac Electrophysiology - Clinical implication of local impedance (LI) for radiofrequency (RF) ablation has not been fully established. This study aimed to investigate...  相似文献   
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Expression of p57/Kip2 protein in pancreatic adenocarcinoma   总被引:14,自引:0,他引:14  
INTRODUCTION: Evaluation of the biologic character of carcinomas requires understanding of cell cycle regulators. AIMS: To investigate p57 expression in human pancreatic adenocarcinoma and cyst adenoma. METHODOLOGY: We examined the expression of p57(Kip2), a member of the Cip/Kip family, in 45 pancreatic adenocarcinomas, 7 cystadenomas, and 7 chronic pancreatitis cases. RESULTS: The p57 labeling index (LI) in duct epithelia in chronic pancreatitis averaged 32.8+/-8.3 and was significantly higher than in normal duct epithelia (18.8+/-6.6; p = 0.0011). For the carcinoma, the LI averaged 46.0+/-20.9, which was significantly higher than that for normal duct epithelia (p < 0.0001) and cystadenoma (16.0 11.2; p = 0.0007). However, it was significantly reduced in cases with stage IV disease (p = 0.0351), lymph node metastasis (p = 0.0003), larger size (p = 0.0094), capsular invasion (p = 0.0462), lymphatic invasion (p = 0.0351), and cell proliferating activity (p = 0.0002). In multivariate analysis, p57 LI in pancreatic adenocarcinoma was independently linked to high proliferating activity (p = 0.0230). CONCLUSION: These results suggest that p57 plays a role in the hyperplastic change of the ducts in chronic pancreatitis and that pS7 overexpression contributes to the downregulation of cell proliferation, and its decreased expression contributes to the progression of pancreatic adenocarcinoma.  相似文献   
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