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Normal aging is associated with cognitive decline and underlying brain dysfunction. Previous studies concentrated less on brain network changes at a systems level. Our goal was to examine these age-related changes of fMRI-derived activation with a common network parcellation of the human brain function, offering a systems-neuroscience perspective of healthy aging. We conducted a series of meta-analyses on a total of 114 studies that included 2035 older adults and 1845 young adults. Voxels showing significant age-related changes in activation were then overlaid onto seven commonly referenced neuronal networks. Older adults present moderate cognitive decline in behavioral performance during fMRI scanning, and hypo-activate the visual network and hyper-activate both the frontoparietal control and default mode networks. The degree of increased activation in frontoparietal network was associated with behavioral performance in older adults. Age-related changes in activation present different network patterns across cognitive domains. The systems neuroscience approach used here may be useful for elucidating the underlying network mechanisms of various brain plasticity processes during healthy aging. 相似文献
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Rapid industrial and technological development has impacted ecosystem homeostasis strongly. Arsenic is one of the most detrimental environmental toxins and its management with chelating agents remains a matter of concern due to associated adverse effects. Thus, safer and more effective alternative therapy is required to manage arsenic toxicity. Based on existing evidence, native and indigenous plant-based active biomolecules appear as a promising strategy to mitigate arsenic-induced toxicity with an acceptable safety profile. In this regard, various phytochemicals (flavonoids and stilbenoids) are considered important classes of polyphenolic compounds with antioxidant and chelation effects, which may facilitate the removal of arsenic from the body more effectively and safely with regard to conventional approaches. This review presents an overview of conventional chelating agents and the potential role of flavonoids and stilbenoids in ameliorating arsenic toxicity. This report may provide a roadmap for identifying novel prophylactic/therapeutic strategies for managing arsenic toxicity. 相似文献
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This study aimed to observe the therapeutic effects of magnesium lithospermate B on acute and chronic colitis induced by dextran sodiumsulfate (DSS) and the role of inflammasome complex (NOD-like receptor protein, NLRP; apoptosis-associated speck-like protein containing, ASC; caspase-1). Establishment of acute and chronic colitis models were by using 5% DSS oral administration in BALB/C male mice. Magnesium lithospermate B (240 mg/kg body weight) was given by subcutaneous injection. Samples were collected for biomarker assay, histological examination, immunohistochemical evaluation and western blot. There was obvious increase in TNF-α level and NLPR3, ASC, and caspase-1 expressions in acute and chronic colitis groups compared with the normal control. Significant decrease of the tumor necrosis factor-α level and the expressions of NLPR3, ASC, and caspase-1 were observed after treatment with magnesium lithospermate B. This study showed that magnesium lithospermate B could be used to treat acute and chronic colitis by inhibiting the activation of the NLRP3/ASC/Caspase-1 pathway. 相似文献
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Wang JG Liu L Zagato L Xie J Fagard R Jin K Wang J Li Y Bianchi G Staessen JA Liu L 《Journal of molecular medicine (Berlin, Germany)》2004,82(10):715-722
We recently found in a white population that the genes encoding angiotensin-converting enzyme (ACE, I/D polymorphism), -adducin (Gly460Trp), and aldosterone synthase (–344C/T) jointly influence renal function. We therefore investigated in a Chinese population the associations between the serum concentrations of creatinine and uric acid and these three genetic polymorphisms. We genotyped 471 ethnic Han Chinese subjects from 125 nuclear families recruited in northern China via random population sampling (75%) and at specialized hypertension clinics (25%). We performed population-based and family-based association analyses using generalized estimating equations (GEE) and quantitative transmission disequilibrium test (QTDT), respectively, while controlling for covariables. The participants were 39.7 years old and included 235 women (49.9%). The blood pressure measured at the subjects homes averaged 126/80 mmHg. Mean values were 71 µmol/l for serum creatinine, 111 ml min–1 1.73 m–2 for calculated creatinine clearance, and 236 µmol/l for serum uric acid. With adjustment for covariables, GEE analyses of single genes demonstrated that serum uric acid, but not serum creatinine, was positively associated with the ACE D allele. Serum uric acid concentrations were 15.8 µmol/l (95% confidence interval 3.3–28.2) and 25.7 µmol/l (11.1–40.2) higher in DD homozygotes than in ID and II subjects, respectively. Further GEE analyses of the three genes combined showed that the association between serum uric acid and the ACE polymorphism was confined to carriers of the -adducin Gly and/or aldosterone synthase C alleles. Sensitivity analyses in parents and offspring separately as well as QTDT analyses were confirmatory. Among 114 informative offspring carrying the -adducin Gly allele serum uric acid was significantly and positively associated with the transmission of the ACE D allele (=20.7 µmol/l). In conclusion, the present study extends our previous findings on the combined effects of the three candidate genes and supports the concept that these genetic polymorphisms jointly influence renal function. 相似文献
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目的 探讨维生素D受体(VDR)基因多态性与妊娠期糖尿病(GDM)之间的关系,为GDM的机制研究提供线索与依据。方法 采用病例对照研究设计,以2012年3月1日至2014年7月30日在山西医科大学第一医院产科分娩的孕妇为研究对象,其中334例被诊断为GDM,按年龄、妊娠时间及居住地1∶1匹配相应健康对照。对研究对象进行DNA基因分型,剔除基因分型缺失率>10%者,最终323例病例和320例对照纳入研究。在共显性、显性、隐性和等位基因遗传模型下,通过非条件logistic回归分析VDR基因位点多态性和GDM之间的关系,并采用Haploview软件分析单倍型与GDM之间的关系。结果 在基因水平上,VDR基因与GDM发病风险有关(P<0.05)。在调整孕前BMI、糖尿病家族史后,rs7967152位点在共显性(AC vs. AA,OR=1.58,95%CI:1.13~2.21)、显性(AC+CC vs. AA,OR=1.58,95%CI:1.15~2.18)和等位基因(C vs. A,OR=1.41,95%CI:1.10~1.82)遗传模型下与GDM风险升高有关;rs2238140位点在共显性(AA vs. GG,OR=2.24,95%CI:1.19~4.20)、显性(GA+AA vs. GG,OR=1.48,95%CI:1.07~2.03)和等位基因(A vs. G,OR=1.43,95%CI:1.11~1.83)遗传模型下与GDM风险升高有关。在共显性和显性遗传模型下,孕妇携带rs2853564位点AG基因型、AG+GG基因型(OR=1.46,95%CI:1.04~2.05;OR=1.45,95%CI:1.05~2.00)与携带AA基因型相比,是GDM的危险因素;孕妇携带rs2853566位点AG基因型、AG+GG基因型(OR=1.43,95%CI:1.03~2.00;OR=1.41,95%CI:1.02~1.94)与携带AA基因型相比,是GDM的危险因素。在VDR基因内由rs1544410、rs7967152组成的单倍型区块,其GC单倍型与是GDM的危险因素(OR=1.50,95%CI:1.15~1.97)。结论 VDR基因rs7967152、rs2238140、rs2853564、rs2853566位点多态性和区块(rs1544410、rs7967152)GC单倍型与GDM的发病风险升高有关。 相似文献
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