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1.
Adult neurogenesis is a highly regulated process during which new neurons are generated from neural stem cells in two discrete regions of the adult brain: the subventricular zone of the lateral ventricle and the subgranular zone of the dentate gyrus in the hippocampus. Defects of adult hippocampal neurogenesis have been linked to cognitive decline and dysfunction during natural aging and in neurodegenerative diseases, as well as psychological stress-induced mood disorders. Understanding the mechanisms and pathways that regulate adult neurogenesis is crucial to improving preventative measures and therapies for these conditions. Accumulating evidence shows that mitochondria directly regulate various steps and phases of adult neurogenesis. This review summarizes recent findings on how mitochondrial metabolism, dynamics, and reactive oxygen species control several aspects of adult neural stem cell function and their differentiation to newborn neurons. It also discusses the importance of autophagy for adult neurogenesis, and how mitochondrial and autophagic dysfunction may contribute to cognitive defects and stress-induced mood disorders by compromising adult neurogenesis. Finally, I suggest possible ways to target mitochondrial function as a strategy for stem cell-based interventions and treatments for cognitive and mood disorders. 相似文献
2.
L. Berkowitz and E. Harmon-Jones (see record 2004-15096-001) challenge appraisal theories of emotion by describing 2 sets of conditions (physical discomfort and anger-related muscle actions) in which anger appears to be elicited in the absence of theoretically predicted appraisals. In response, the authors discuss the ability of the specific appraisal model they have developed (e.g., C. A. Smith & L. D. Kirby, 2000, 2001; C. A. Smith & R. S. Lazarus, 1990) to account for such instances of anger. First, a number of issues are clarified relevant to the authors' model, including the nature of both the cognitive operations underlying appraisal and the specific appraisals hypothesized to evoke anger. The authors then describe how their model can account for the instances of anger described by L. Berkowitz and E. Harmon-Jones and how both accounts might be tested. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Nguyen Khanh Toan Nguyen Chi Tai Soo-A Kim Sang-Gun Ahn 《International journal of molecular sciences》2021,22(1)
Salivary gland dysfunction induces salivary flow reduction and a dry mouth, and commonly involves oral dysfunction, tooth structure deterioration, and infection through reduced salivation. This study aimed to investigate the impact of aging on the salivary gland by a metabolomics approach in an extensive aging mouse model, SAMP1/Klotho -/- mice. We found that the salivary secretion of SAMP1/Klotho -/- mice was dramatically decreased compared with that of SAMP1/Klotho WT (+/+) mice. Metabolomics profiling analysis showed that the level of acetylcholine was significantly decreased in SAMP1/Klotho -/- mice, although the corresponding levels of acetylcholine precursors, acetyl-CoA and choline, increased. Interestingly, the mRNA and protein expression of choline acetyltransferase (ChAT), which is responsible for catalyzing acetylcholine synthesis, was significantly decreased in SAMP1/Klotho -/- mice. The overexpression of ChAT induced the expression of salivary gland functional markers (α–amylase, ZO-1, and Aqua5) in primary cultured salivary gland cells from SAMP1/Klotho +/+ and -/- mice. In an in vivo study, adeno-associated virus (AAV)-ChAT transduction significantly increased saliva secretion compared with the control in SAMP1/Klotho -/- mice. These results suggest that the dysfunction in acetylcholine biosynthesis induced by ChAT reduction may cause impaired salivary gland function 相似文献
5.
Marilyn Arosemena Farah A. Meah Kieren J. Mather Sarah A. Tersey Raghavendra G. Mirmira 《International journal of molecular sciences》2021,22(4)
Type 2 diabetes (T2D) typically occurs in the setting of obesity and insulin resistance, where hyperglycemia is associated with decreased pancreatic β-cell mass and function. Loss of β-cell mass has variably been attributed to β-cell dedifferentiation and/or death. In recent years, it has been proposed that circulating epigenetically modified DNA fragments arising from β cells might be able to report on the potential occurrence of β-cell death in diabetes. Here, we review published literature of DNA-based β-cell death biomarkers that have been evaluated in human cohorts of islet transplantation, type 1 diabetes, and obesity and type 2 diabetes. In addition, we provide new data on the applicability of one of these biomarkers (cell free unmethylated INS DNA) in adult cohorts across a spectrum from obesity to T2D, in which no significant differences were observed, and compare these findings to those previously published in youth cohorts where differences were observed. Our analysis of the literature and our own data suggest that β-cell death may occur in subsets of individuals with obesity and T2D, however a more sensitive method or refined study designs are needed to provide better alignment of sampling with disease progression events. 相似文献
6.
Helena Kratochvílov Milo Mrz Barbora J. Kasperov Daniel Hlav
ek Jakub Mahrík Ivana Lakov Anna Cinkajzlov Zdenk Matloch Zdeka Lacinov Jaroslava Trnovsk Peter Ivk Peter Novodvorský Ivan Netuka Martin Haluzík 《International journal of molecular sciences》2021,22(9)
The aim of our study was to analyze mitochondrial and endoplasmic reticulum (ER) gene expression profiles in subcutaneous (SAT) and epicardial (EAT) adipose tissue, skeletal muscle, and myocardium in patients with and without CAD undergoing elective cardiac surgery. Thirty-eight patients, 27 with (CAD group) and 11 without CAD (noCAD group), undergoing coronary artery bypass grafting and/or valvular surgery were included in the study. EAT, SAT, intercostal skeletal muscle, and right atrium tissue and blood samples were collected at the start and end of surgery; mRNA expression of selected mitochondrial and ER stress genes was assessed using qRT-PCR. The presence of CAD was associated with decreased mRNA expression of most of the investigated mitochondrial respiratory chain genes in EAT, while no such changes were seen in SAT or other tissues. In contrast, the expression of ER stress genes did not differ between the CAD and noCAD groups in almost any tissue. Cardiac surgery further augmented mitochondrial dysfunction in EAT. In our study, CAD was associated with decreased expression of mitochondrial, but not endoplasmic reticulum stress genes in EAT. These changes may contribute to the acceleration of coronary atherosclerosis. 相似文献
7.
学生是学习的主体,在教学中要充分体现学生的自主作用。通过分析ASP.NET教学中存在的主要问题及闯关式教学的优势,对ASP.NET课程教学方法进行了探索改革,将闯关式教学模式应用到ASP.NET课程教学过程中,通过设置由易到难的五级关卡激发学生去挑战的策略来实施教学。教学实践表明,该教学模式激发了学生学习的动力,使学生学习更具有目标性,增强了学生在闯关过程中体验到学习成功的乐趣。 相似文献
8.
基于信誉构建信任机制是解决虚拟计算环境[1]中行为可信问题的重要途径。现有信誉模型对不良行为的动态适应能力和对信誉信息的有效聚合能力不足,缺乏鼓励节点积极参与诚实合作的有效机制。本文提出一种基于惩罚激励机制的信誉管理模型PERep,根据自主元素行为特征和信誉状态区分交易行为的合作与偏离,并对偏离行为进行惩罚;给出了PERep的分布式实现。实验表明,PERep能准确地区分诚实交易和恶意行为,有效提高自主元素诚实交易的积极性并减少恶意行为的危害。 相似文献
9.
Server applications augmented with behavioral adaptation logic can react to environmental changes, creating self‐managing server applications with improved quality of service at runtime. However, developing adaptive server applications is challenging due to the complexity of the underlying server technologies and highly dynamic application environments. This paper presents an architecture framework, the Adaptive Server Framework (ASF), to facilitate the development of adaptive behavior for legacy server applications. ASF provides a clear separation between the implementation of adaptive behavior and the business logic of the server application. This means a server application can be extended with programmable adaptive features through the definition and implementation of control components defined in ASF. Furthermore, ASF is a lightweight architecture in that it incurs low CPU overhead and memory usage. We demonstrate the effectiveness of ASF through a case study, in which a server application dynamically determines the resolution and quality to scale an image based on the load of the server and network connection speed. The experimental evaluation demonstrates the performance gains possible by adaptive behavior and the low overhead introduced by ASF. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
10.
复杂装备故障预测与健康管理系统初探 总被引:7,自引:1,他引:6
故障预测与健康管理(PHM)系统是新型维修保障模式—自主后勤保障的重要组成部分,对提高复杂装备的战备完好性和降低维修成本具有重要意义;首先介绍PHM系统基本概念及主要组成,并对在复杂装备全寿命周期实施PHM的必要性进行分析;综合论述了PHM系统实现中的关键支撑技术:基于RCM分析的方案设计、基于匹配度的健康状态评估和基于剩余寿命预测的维修决策;最后给出了PHM系统在无人机装备中的应用实例;国内外应用情况表明,PHM系统可显著提高维修保障效率并降低维修保障费用,可实现经济可承受性目标。 相似文献