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Analysis of factors influencing chronic renal failure progression   总被引:1,自引:0,他引:1  
One of the most important characteristics of chronic renal failure (CRF) is its progression to end stage renal disease. CRF progression depends of many factors indicated in numerous experimental and clinical studies. The present study was undertaken with the aim to examine the role of sex, etiology of CRF, renal function at the beginning of the study, hypertension and protein intake on CRF progression. Ninety-two patients (47 female and 45 male) aged between 17 and 70, with various underlying kidney diseases and various degrees of CRF were followed for 8 years. CRF progression was expressed as Creatinine clearance (CCr) and reciprocal values of serum Creatinine (SCr) against time. CRF progression was slower in women than in men, but not significantly. Patients with diabetic nephropathy (b = 0.00006) and glomerulonephritis (b = 0.00005) had faster progression of CRF than patients with nephrosclerosis (b = 0.00002), tubulointerstitial nephritis (b = 0.00003) and polycystic kidney disease (b = 0.00003). The fastest progression of CRF was in patients with the lowest SCr values at the beginning of the study. Proper regulation of blood pressure was the most important factor in slowing down CRF progression, independently of kind of antihypertensive drugs. Neither angiotensin converting enzyme inhibitors (b = -0.00001) nor calcium channel blockers (b = -0.00002) showed better effects on CRF progression slowing down in comparison with other antihypertensive drugs (b = -0.00001). Low protein diet slowed down CRF progression, but not significantly. In conclusion, our retrospective study confirms that CRF progression depends on sex, underlying renal diseases and serum Creatinine levels at the beginning of the study. Good regulation of blood pressure and low protein diet can slow down CRF progression.  相似文献   
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The situation of end-stage renal disease (ESRD) patients in central and eastern Europe was very poor for many years during the so called socialistic era. Economical and political liberation resulted in the significant growth of renal replacement facilities in this region. The number of hemodialysis units increased significantly (56%) during the period 1990–1996, and the number of patients treated with this modality has risen by 75%. More dramatic progress was achieved in peritoneal dialysis. The number of units performing this method of renal replacement therapy (RTT) increased by 277% and the number of patients by more than 300%. Not only quantitative but also qualitative changes were observed. More modern hemodialysis machines installed in the vast majority of units allow for the performance of bicarbonate dialysis, controlled ultrafiltration, and sodium profile modeling. Also, a wider choice of biocompatible dialyzers has become available during the last few years. The number of centers performing renal transplantation has increased significantly, but the number of renal transplants has not followed this progress. Despite all the progress, further development of all RRT methods is necessary to achieve acceptance rates comparable to those observed in developed countries.  相似文献   
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The efficiency of human recombinant epoetin in alleviating anemia in hemodialyzed patients has been well documented. However, the effects of rhEPO therapy in correction of antioxidant capacity are not completely explained. In this study we examined both extracellular (plasma) and intracellular (red blood cells) antioxidant potential in hemodialyzed patients before and after three and six months of epoetin treatment by evaluating markers of oxidative stress (malondialdehyde) and antioxidant capacity (thiol groups, superoxide dismutase, and glutathione peroxidase). Six months of treatment with epoetin was followed by significant increases in thiol groups, superoxide dismutase and glutathione peroxidase activities in both plasma and red blood cells of hemodialyzed patients. Hence, during accelerated erythropoiesis, an increase in the number of young hematopoietic cells may replenish erythrocyte superoxide dismutase and glutathione peroxidase activity. However, the consequences of an imbalance between enzymatic antioxidant system (higher superoxide dismutase and lower glutathione peroxidase activity) that exists in these patients are the very high red blood cell and plasma malondialdehyde levels. These results suggest that, in spite of epoetin treatment and improvement in red blood cells and plasma antioxidant capacity, the production of reactive oxygen species overwhelms the intracellular and extracellular antioxidant capacity.  相似文献   
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BACKGROUND: Almost 50 years ago Balkan Endemic Nephropathy (BEN) was first described in Serbia in the village of Sopi? where the first field examination was carried out in 1971. Our aim was to find out whether BEN is still present in this region. METHODS: Prevalence data on BEN from a field examination run in 1971 were compared with the results of a cross-sectional study conducted in the same village in 1992. In addition, every new case of the disease diagnosed between 1971 and 1992 was recorded retrospectively. The prospective study included 50 members of five BEN families randomly selected from 28 BEN families registered in the village Sopi? in 1992. The objective survey and examination of global and tubular kidney function was carried out in all examined persons once yearly in 1998, 1999, and 2000. RESULTS: The overall prevalence of BEN was 6.4% in 1971 and 8.9% in 1992. In the period of 21 years, 161 new BEN patients were detected in 28 families in which the disease had already been recorded. No new family affected by BEN and none of the new patients in 47 families registered previously as nonaffected were discovered. In the prospective study of five BEN families, three new BEN cases were discovered among 50 members, and two patients fulfilled criteria for BEN-suspected ones. CONCLUSION: Balkan Endemic Nephropathy (BEN) is still present in the village of Sopi?, but the clinical course of the disease became more protracted over time. New cases of BEN appeared only in the affected families.  相似文献   
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OBJECTIVE: We hypothesize that vascular endothelial growth factor, a known angiogenic and permeability factor that is locally expressed in fetal membranes and decidua, may be the primary regulator in the pathway that eventually leads to preterm premature rupture of membranes. Our objective was to test the hypothesis that, both in the presence and in the absence of histologic chorioamnionitis, there is an increased expression of the vascular endothelial growth factor gene and its receptor Flt-1 in the human fetal membranes. STUDY DESIGN: Membranes were sampled from a region that was distinct as the rupture site from three groups of patients with preterm premature rupture of membranes. Groups 1 and 2 differed only in the length of the latency period from rupture of the membranes to delivery. Group 3 included preterm patients with intact membranes, who acted as control subjects. All patients who were selected for the study lacked clinical signs of chorioamnionitis and were delivered by cesarean delivery. Tissue samples were analyzed for interleukin-6 gene expression by Northern blot analysis and for the presence of interleukin-6 protein by immunocytochemistry. The expression of vascular endothelial growth factor and Flt-1 genes was analyzed by in situ hybridization. RESULTS: All tissue samples from group 1 and five tissue samples from group 2 (designated as group 2A) showed expression of the interleukin-6 gene and the presence of interleukin-6 protein in the fetal membranes (P <.001) and were therefore identified as inflamed. Five tissue samples from the patients in group 2 (designated as group 2B) and all control tissue samples showed neither evidence of interleukin-6 gene expression nor the presence of its protein and therefore were identified as not inflamed. Vascular endothelial growth factor and Flt-1 gene expression were increased significantly in the fetal membrane and decidua samples that were obtained from the noninflamed tissues from group 2B (P <.005) yet showed further enhancement in expression in the inflamed tissues. CONCLUSION: The expression patterns of vascular endothelial growth factor and Flt-1 genes are indicative of a molecular pathologic condition of fetal membranes, regardless of their inflammatory status, which suggests their role as a primary regulator of preterm premature rupture of membranes.  相似文献   
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The role of autophagy, a process in which the cell self-digests its own components, was investigated in glioma cell death induced by the hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase-inhibiting drug simvastatin. Induction of autophagy and activation of autophagy-regulating signalling pathways were analyzed by immunoblotting. Flow cytometry/fluorescent microscopy was used to assess autophagy-associated intracellular acidification and apoptotic markers (phosphatidylserine exposure, DNA fragmentation and caspase activation). Cell viability was determined by crystal violet, MTT or LDH release assay. Simvastatin treatment of U251 and C6 glioma cell lines caused the appearance of autophagolysosome-like intracytoplasmic acidic vesicles. The induction of autophagy in U251 cells was confirmed by the upregulation of autophagosome-associated LC3-II and pro-autophagic beclin-1, as well as by the downregulation of the selective autophagic target p62. Simvastatin induced the activation of AMP-activated protein kinase (AMPK) and its target Raptor, while simultaneously downregulating activation of Akt. Mammalian target of rapamycin (mTOR), a major AMPK/Akt downstream target and a major negative autophagy regulator, and its substrate p70 S6 kinase 1 were also inhibited by simvastatin. Mevalonate, the product of HMG-CoA reductase enzymatic activity, AMPK siRNA or pharmacological inactivation of AMPK with compound C suppressed, while the inhibitors of Akt (10-DEBC hydrochloride) and mTOR (rapamycin) mimicked autophagy induction by simvastatin. Inhibition of autophagy with bafilomycin A1, 3-methyladenine and LC3β shRNA, as well as AMPK inhibition with compound C or AMPK siRNA, markedly increased apoptotic death of simvastatin-treated U251 cells. These data suggest that inhibition of AMPK-dependent autophagic response might sensitize glioma cells to statin-induced apoptotic death.  相似文献   
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In the present study, we analysed the relations among the quality of mother–child shared reading, child’s storytelling and family literacy environment. The sample included 20 mother–child dyads, with 5-year-old children, who were recorded during shared reading. The quality of shared reading was assessed with the Scale for Observing Shared Reading while children’s storytelling was assessed with the textless book Frog Goes to Dinner. We found that the quality of mother–child shared reading was related to the coherence of children’s stories and to the factors of home literacy environment. Child’s age when parents started reading to him, the number of all books and children’s books in child’s home together explained 43.1% of the variance in the quality of shared reading. The findings give an insight into the process of the quality of the interactive reading between a child and an adult and emphasize the importance of shared reading for child’s storytelling.  相似文献   
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