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41.
Hoyaux D Decaestecker C Heizmann CW Vogl T Schäfer BW Salmon I Kiss R Pochet R 《Brain research》2000,867(1-2):280-288
Corpora amylacea (C.A.) also named polyglucosan bodies (P.B.) are one of the hallmarks of normal brain aging. Although their functions are not yet clear, C.A. increase in number in patients suffering from neurodegenerative diseases. C.A. contain 88% of hexoses and 4% of proteins. Most of the proteins in C.A. are aging or stress proteins such as heat shock proteins, ubiquitinated proteins and advanced glycation end products which are also proinflammatory products. Stimulated by the potential role played by some S100 proteins in the inflammatory process which may be triggered in C.A., we investigated, by immunohistochemistry, the presence of different S100 proteins (S100A1, S100A2, S100A3, S100A4, S100A5, S100A6, S100A8, S100A9, S100A12 and S100B) in C.A. from normal human brain. Among the ten S100 proteins analyzed, nine (S100A) were detected in C.A. Three S100 proteins (S100A8, S100A9, S100A12) which are highly expressed in activated macrophages and used as inflammatory markers were detected in C.A. S100A8 was, in addition, found in thick neuronal processes from the pons. One (S100B) could not be found in C.A. although it was highly expressed in astrocytes. In C.A., the staining intensity was estimated by computer-assisted microscopy and gave the following order: S100A1 congruent withS100A8 congruent with S100A9>S100A5> or =S100A4>S100A12>S100A6> S100A2=S100A3. The potential inflammatory role played by S100 proteins in C.A. is discussed. 相似文献
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蛋氨酸限制(Methionine restriction,MetR)作为饮食限制的方法之一,能够改善多种无脊椎动物、啮齿类动物及包括人类灵长类动物的衰老及其相关疾病.但MetR对衰老的具体调节作用机制尚未完全明确,目前除了与饮食限制的共有机制以外,越来越多的研究表明内源性硫化氢(Endogenous hydrogen ... 相似文献
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衡阳市已进入老龄化社会.我们必须加快经济发展,为解决老龄化问题奠定坚实的物质基础;强化老龄委、老龄办事机构职能;建立健全有关法律法规体系;巩固家庭养老为主的养老方式;扩大社区养老职能,建立老年公寓,提供全方位的养老服务.让老年人拥有一个幸福的晚年,从而促进进经济建设的可持续发展. 相似文献
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目的:以长期培养的牙周膜和牙龈成纤维细胞模拟老化细胞,在体外创面模型中,就增龄对牙周细胞覆盖创面的影响进行评价。方法:以反复传代12代以上的牙周膜、牙龈成纤维细胞作为老化(实验组)细胞,5代以内的牙周膜、牙龈成纤维细胞作为正常对照组。4种细胞接种于盖玻片直至融合。机械方法刮除部分融合细胞,形成宽约7mm的无细胞条带,即体外创面。创面形成后继续培养2、6、9d,固定玻片并作结晶紫染色。以计算机辅助图像分析系统对细胞覆盖体外创面的面积进行百分比定量,采用SAS6.12软件包进行样本均数的t检验。结果:实验组与对照组比较,实验组的牙周膜、牙龈成纤维细胞覆盖创面面积明显较少,创面形成第6、9d,其覆盖创面面积显著低于对照组,差异有显著性(P<0.05)。实验组与对照组牙周膜、牙龈成纤维细胞覆盖创面面积存在差异,对照组创面形成后第9d牙龈成纤维细胞覆盖创面面积显著高于牙周膜细胞,差异有显著性(P<0.05)。结论:老化牙周膜、牙龈成纤维细胞覆盖创面的能力弱于正常细胞。增龄可能损害牙周细胞对创面的覆盖能力。 相似文献
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Rhonda S. Sebastian Marie T. Fanelli Kuczmarski Joseph D. Goldman Alanna J. Moshfegh Alan B. Zonderman Michele K. Evans 《Nutrients》2022,14(9)
Despite research that suggests flavonoids protect against metabolic syndrome (MetS) and evidence that intake of these compounds differs by race, knowledge about whether flavonoid–MetS associations vary among racial groups is limited. This study sought to estimate usual total flavonoid intake in African American and White adults and assess its sex- and sex/race-specific associations with MetS and its risk factors. Analysis of cross-sectional data from 1837 adults participating in the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study were analyzed. Usual total flavonoid intake was estimated using the NCI Method, and logistic regression measured its linkages with health outcomes. Among males overall and when stratified by race, odds of MetS and its risk factors low high-density lipoprotein cholesterol (HDL-C) and elevated glucose were lower at the 75th percentile of usual total flavonoid intake than at the 25th percentile (OR for MetS = 0.62; 95% CI = 0.53, 0.71). However, low HDL-C and elevated glucose were positively associated with usual flavonoid intake among females. The comparable associations by race within sex imply that the relationships between flavonoid and health outcomes may be evident across an array of intakes. 相似文献
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Maria Heloisa M. Shimizu Rildo A. VolpiniAna Carolina de Bragança Renata CamposDaniele Canale Talita R. SanchesLúcia Andrade Antonio C. Seguro 《Experimental gerontology》2013
The aim of this study was to evaluate the effects of N-acetylcysteine (NAC) on renal function, as well as on sodium and water transporters, in the kidneys of aged rats. Normal, 8-month-old male Wistar rats were treated (n = 6) or not (n = 6) with NAC (600 mg/L in drinking water) and followed for 16 months. At the end of the follow-up period, we determined inulin clearance, serum thiobarbituric acid reactive substances (TBARS), serum cholesterol, and urinary phosphate excretion. In addition, we performed immunohistochemical staining for p53 and for ED-1-positive cells (macrophages/monocytes), together with Western blotting of kidney tissue for NKCC2, aquaporin 2 (AQP2), urea transporter A1 (UT-A1) and Klotho protein. At baseline, the two groups were similar in terms of creatinine clearance, proteinuria, cholesterol, and TBARS. At the end of the follow-up period, NAC-treated rats presented greater inulin clearance and reduced proteinuria, as well as lower serum cholesterol, serum TBARS, and urinary phosphate excretion, in comparison with untreated rats. In addition, NAC-treated rats showed upregulated expression of NKCC2, AQP2, and UT-A1; elevated Klotho protein expression, low p53 expression, and few ED-1 positive cells. In conclusion, we attribute these beneficial effects of NAC (the significant improvements in inulin clearance and in the expression of NKCC2, AQP2, and UT-A1) to its ability to decrease oxidative stress, inhibit p53 expression, minimize kidney inflammation, and stimulate Klotho expression. 相似文献