hOGG1基因在Cr(Ⅵ)诱导线粒体DNA氧化损伤中的作用

目的探讨hOGG1基因在Cr(Ⅵ)诱导线粒体DNA氧化损伤中的修复作用。方法取不同浓度的Cr(Ⅵ)(0、2、8和32μmol/L)处理L-02肝细胞24h,分别测定细胞内活性氧簇(ROS)与hOGG1 mRNA表达水平和线粒体内8-羟基脱氧鸟苷(8-OHdG)与hOGG1基因表达的人类8-羟基鸟嘌呤DNA糖苷酶蛋白(hOGG1蛋白)水平。结果 8μmol/L和32μmol/L剂量组与对照组比较,细胞内ROS平均水平及线粒体内8-OhdG平均水平均明显增加(P<0.05),而hOGG1基因mRNA水平和线粒体内hOGG1蛋白水平,与对照组比较,2μmol/L剂量组两者水平均上升(P<0.05),32μmol/L剂量组两者水平均降低(P<0.05)。结论 Cr(Ⅵ)可诱导细胞内ROS水平增加,引起线粒体DNA氧化损伤,而hOGG1基因表达水平的改变,影响了线粒体DNA的修复能力。hOGG1基因在Cr(Ⅵ)诱导线粒体DNA氧化损伤中起到了重要的作用。     

肾脏谷胱甘肽代谢系统及其毒理学意义

谷胱甘肽 (GSH)主要在肝脏合成 ,经肠肝和肾肝循环运送到肾脏 ,经肾小球滤过后 ,可被位于肾小管细胞刷状缘的降解酶水解为氨基酸 ,重吸收后再合成GSH ,但主要是在肾小管细胞基底膜侧经载体介导以完整的三肽形式吸收。在细胞内有两个重要的GSH池 ,一个是细胞浆 ,一个是线粒体 ,线粒体不能合成GSH ,细胞浆GSH通过线粒体内膜的有机阴离子载体转运到线粒体内 ,在保护细胞免受氧化损伤中起重要作用。肾近曲小管细胞和远曲小管细胞对氧化损伤的敏感性不同 ,与细胞内GSH的含量不同和线粒体内膜的阴离子载体对GSH的转运能力的不同有关。GSH代谢系统具有解毒和活化的双重毒理学意义     

093 肾脏谷胱甘肽代谢系统及其毒理学意义

谷胱甘肽(GSH)主要在肝脏合成,经肠肝和肾肝循环运送到肾脏,经肾小球滤过后,可被位于肾小管细胞刷状缘的降解酶水解为氨基酸,重吸收后再合成GSH,但主要是在肾小管细胞基底膜侧经载体介导以完整的三肽形式吸收.在细胞内有两个重要的GSH池,一个是细胞浆,一个是线粒体,线粒体不能合成GSH,细胞浆GSH通过线粒体内膜的有机阴离子载体转运到线粒体内,在保护细胞免受氧化损伤中起重要作用.肾近曲小管细胞和远曲小管细胞对氧化损伤的敏感性不同,与细胞内GSH的含量不同和线粒体内膜的阴离子载体对GSH的转运能力的不同有关.GSH代谢系统具有解毒和活化的双重毒理学意义.     

沉默信息调节因子3蛋白对线粒体代谢和凋亡调节的研究进展

沉默信息调节因子3(sirt3)是线粒体烟碱腺嘌呤二核苷酸(NAD)依赖的去乙酰化蛋白,是调节线粒体代谢关键酶,可维持细胞内稳态平衡,在线粒体氧化代谢、能量代谢、信号调节和细胞凋亡等活动中发挥重要作用。sirt3是重要的凋亡调节因子,调节线粒体生物学效应和氧化应激水平,抵抗神经元细胞凋亡,其缺失可引起线粒体代谢异常和细胞损伤,甚至引起细胞凋亡。笔者综述了sirt3在线粒体三羧酸循环(TCA)、脂肪酸氧化等代谢活动和细胞凋亡中的重要作用,阐明sirt3可以维持线粒体的正常代谢活动,抵抗细胞凋亡,为肿瘤等疾病的研究提供重要靶点。     

二氧化硫对大鼠肝线粒体的损伤作用

二氧化硫 (SO2 )是一种常见的大气污染物 ,主要通过人和动物的呼吸系统进入机体 ,并以SO2 -3 和HSO-3 形态随血液分布全身而发挥生物学作用。SO2 吸入可引起小鼠各种组织器官的氧化损伤作用[1] ,但有关SO2 对亚细胞组分的影响尚未见报道。在真核生物中线粒体是进行氧化磷酸化的细胞器 ,是细胞内能量供应的场所 ,同时线粒体的氧化磷酸化极易产生自由基 ,是自由基产生的主要途径[2 ] 。我们以大鼠肝线粒体为材料 ,研究SO2 吸入后大鼠肝线粒体及SO2 体内衍生物亚硫酸盐对分离线粒体损伤的影响 ,从亚细胞水平来阐明SO2 的毒作用机制。一…     

窒息后新生儿心肌线粒体的损伤

新生儿窒息缺氧对心肌线粒体的损伤在心脏损害的过程中起着重要的作用。心肌线粒体是产生内源性自由基的主要场所 ,氧自由基攻击导致膜流动性下降 ,影响线粒体功能和膜内酶活性。心肌细胞缺血缺氧时细胞内钙超载继发线粒体钙超载 ,使线粒体内膜钙离子依赖小孔开放 ,线粒体膜电位降低和氧化磷酸化脱偶联。缺氧缺血时心肌线粒体内一氧化氮活酶 (NOS)类似物活性增强 ,NO产生增多 ,抑制线粒体呼吸链复合物活性和正常电子流 ,增加超氧阴离子的形成 ,导致心肌线粒体呼吸链功能受损 ,最终使ATP合成受阻 ,心肌能量供应不足 ,出现窒息新生儿心脏损害的临床表现。     

窒息后新生儿心肌线粒体的损伤

新生儿窒息缺氧对心肌线粒体的损伤在心脏损害的过程中起着重要的作用。心肌线粒体是产生内源性自由基的主要场所，氧自由基攻击导致膜流动性下降，影响线粒体功能和膜内酶活性。心肌细胞缺血缺氧时细胞内钙超载继发线粒体钙超载，使线粒体内膜钙离子依赖小孔开放，线粒体心肌细胞缺血缺氧时细胞内钙超载继发线粒体钙超载，使线粒体内膜钙离子依赖小孔开放，线粒体膜电位降低和氧化磷酸化脱偶联。缺氧缺血时心肌线粒体内一氧化氮活酶（NOS）类似物活性增强，NO产生增多，抑制线粒体呼吸链复合物活性和正常电子流，增加超氧阴离子的形成，导致心肌线粒体NO产生增多，抑制线粒体呼吸逻复合活性和正常电子流，增加超氧阴离子的形成，导致心肌线粒体呼吸链功能受损，最终使ATP合成受阻，心肌能量供应不足，出现窒息新生儿心脏损害的临床表现。     

二氯乙烯对体外培养人皮肤角质形成细胞的氧化损伤作用

目的探讨二氯乙烯(dichloroethylene,DCE)对体外培养的人皮肤角质形成细胞(keratinocyte,KC)的氧化损伤作用。方法使用2.800、1.400、0.700、0.350、0.175 mmol/L的DCE对体外培养的人KC染毒4 h,检测细胞活力和细胞内MDA、ROS含量、SOD活性,以及线粒体内8-羟基脱氧鸟嘌呤(8-hydroxy-2-deoxyguanosine,8-OHdG)水平。结果经不同浓度DCE作用4 h后,细胞活力无明显改变。随着DCE浓度升高,细胞内MDA和ROS水平呈上升趋势,而SOD活性呈下降趋势,与溶剂对照组相比较差异有统计学意义;线粒体内8-OHdG水平也随着DCE浓度增加而呈现上升趋势。结论 DCE对人KC有氧化损伤作用。     

sirt3的作用机制及抗肿瘤研究进展

沉默信息调节因子3(sirt3)是线粒体去乙酰化蛋白,参与线粒体蛋白去乙酰化调节,激活超氧化物歧化酶2(superoxide dismutase 2,SOD2),降低线粒体活性氧(reactive oxygen species,ROS)水平,维持细胞内稳态平衡,调节氧化、激素或者电离辐射等应激反应。sirt3是线粒体高保真蛋白和抑癌基因,其去乙酰化活性与长寿相关,因此,sirt3缺失可导致线粒体代谢异常和细胞损伤,引起与衰老相关的病理症状。本文对sirt3的线粒体定位、调节和抑癌作用进行讨论,阐明sirt3可以维持线粒体完整性和正常代谢活动,某种程度上能够抑制肿瘤的发生。     

线粒体DNA的氧化损伤

当活性氧形成与分解的平衡失调时,机体处于氧化应激状态。不论活性氧的增加是内源性还是外源性,均能引起线粒体ＤＮＡ的氧化损伤。线粒体ＤＮＡ自身的结构及功能特点和所在生理位置决定了其比核ＤＮＡ更易于受到氧化损伤的打击,而氧化损伤引起的线粒体ＤＮＡ突变或其基因产物丢失又会进一步促进活性氧的释放。     

创建全国社区卫生服务示范区 促进儿童保健事业发展

宝安区于1996年初在全省率先开展社区卫生服务,始终树立大卫生观念,坚持预防为主、中西医并重的原则,以社区文明建设为指导方针,以促进健康为目的,提供了以个人为中心、家庭为单位、社区为范围、老幼妇残为重点人群的卫生服务。经过多年的努力,全区现建有社区卫生服务中心(站)115个,覆盖人口160多万,已形成覆盖全区的社区卫生服务网络,并于2004年11月通过了全国社区卫生服务示范区的评估。     

Extracting general practice data for timely vaccine coverage estimates: The England experience

In England, primary care providers use standardised coding systems to record health events such as vaccination as well as patient characteristics. This information can be automatically extracted to estimate coverage for vaccine programmes delivered through primary care, in the general population as well as in specific geographical, ethnic, age or clinical groups. This system provides timely vaccine coverage estimates as well as the flexibility to extract tailored data in order to directly inform a continuously evolving national vaccine programme. It is however limited by the quality and completeness of clinical coding in primary care. A centralised, individual-level register would however improve data quality, completeness and reliability and remains the gold standard.     

社区老年人轻度认知功能障碍影响因素病例对照研究

目的 探讨社区老年人轻度认知功能障碍影响因素.方法 采用n:m不等比匹配的病例对照研究方法,应用Spss软件中的Cox回归模型进行不等比匹配logistic回归分析.结果最终入选病例423例,对照925名.通过单因素和多因素Cox回归分析,得出轻度认知功能障碍发生危险因素,其OR值及95%C1分别是:从事体力劳动1.396(1.092～1.785),吸烟1.551(1.021～2.359),血清中较高血糖浓度1.354(1.102～1.664),较高HDL-C 1.543(1.232～1.932),较高LDL-C1.299(1.060～1.592),低雌激素水平1.263(1.031～1.547),高血压1.967(1.438～2.689),糖尿病1.381(1.139～1.675),抑郁症1.406(1.110～1.780),脑血栓1.593(1.307～1.943),较高SBP 1.331(1.129～1.569),ApoEε4型等位基因1.462(1.140～1.873);保护因素有:常读书看报0.610(0.503～0.740),常参加公益活动0.617(0.502～0.757),常做家务0.804(0.665～0.973),退休后有第二职业0.759(0.636 0.906),嗅觉敏锐0.900(0.845～0.958),性格外向0.829(0.699～0.984),性格果断0.811(0.662～0.993).结论从事脑力劳动、健康生活方式以及降低糖尿病、高血压、高血糖、高血脂、抑郁症、脑血管病变发生风险是预防老年人轻度认知功能障碍发生的主要手段.     

Psychosocial Factors That Can Influence the Self-Assessment of Function

What has plagued the evaluation process in this area has been the level of agreement in the wide variation in the measures used to document a construct such as pain, as well as changes in that construct as reflected in the measurement of function. The present article reviews the major psychosocial barriers to assessment/recovery that have been implicated as influencing the self-assessment of function. The following are discussed: secondary gain; secondary loss; emotional distress (such as anger, anxiety and depression); psychopathology; somatization and symptom magnification; compliance and resistance; patient comprehension/mental status; and iatrogenic effects.     

教育机构防控新型冠状病毒肺炎关键环节

新型冠状病毒肺炎疫情在国内已经得到有效控制。为有序恢复中小学校、幼儿园教学活动,保持正常教学秩序,维护师生员工生命安全,中小学校、幼儿园必须抓住关键时间、关键人群、关键场所、关键措施、关键保障等疫情防控的关键环节,进行精准施策、科学防控。     

我国公立医院改革中公益性与积极性的相互关系

供求利益兼容是坚持公益性的本质内涵,人事双赢是调动积极性的本质内涵。公益性和积极性是衡量公立医院发展状态的二级指标,公益性以解决看病贵为主要目标,以实现筹资公平为价值取向,以优化生产关系为中心任务;积极性以解决看病难为主要目标,以提高供给效率为价值取向,以解放和发展生产力为中心任务。新医改形势下,公益性和积极性的地位趋向均衡,公益性和积极性的内容相互融合。     

A Comparison of Self-Esteem, School Achievement, and Friends Between Intercountry Adoptees and Their Siblings

Self-esteem, school achievement, and friends are important factors in social development. A cohort of 123 Canadian families who had adopted 155 international adoptees during the 1970s participated in a recent research project.¹ The project tested these areas and then compared their results with 121 Canadian-born siblings in these adoptive families as well as adolescents and young adults in the general population. These international adoptees fare as well as or better than adolescents and young adults in the general population but not quite as well in some areas as their siblings. Differences were found in some instances between male and female respondents. The authors discuss these findings from a developmental perspective.     

The development of medical sociology in theory and practice in Western Europe 1950-1990

In the first part of the paper, the demographic profile andhealth patterns of Western Europe after the Second World Warand the changes which occurred in the following decades aretraced. So too are developments in medical sciences and in theorganization of health services as well as changes in the economic,social and cultural patterns in society generally. These, aswell as the developing theoretical interests and practical policyconcerns of social scientists, are held to have set the scenefor the characteristic features of medical sociology as theyhave changed in the last 50 years. In the second part, emphasisis given to the tension between the sociologists of and thesociologists in medicine, particularly apparent in the Britishcontext These are held to have had an institutional and career-drivenbase but to have had positive as well as negative effects onthe subdiscipllne.     

Medical education in the Russian Federation

The process of becoming a medical doctor in the Russian Federation is detailed in this paper. There has been a decline in the number of students entering the medical profession, as well as a marked decrease in the faculty members at the medical institutes since perestroika. This is secondary to a marked decrease in financial support as well as falling morale.     

Legal and social aspects of voluntary medical insurance

The structure and functions of voluntary medical insurance (VMI) as observed in Orenburg Region are analyzed in the paper. The held marketing research pointed at problematic aspects of VMI as well as at short-comings in information support; besides, potential sectors of the market of medical services were defined, which are rendered on the basis of VMI contracts--they should be considered in the development of complex and individual VMI programs for the purpose of meeting, as full as possible, the demands of potential consumers as well as for the purpose of optimizing the financial and price policy of insurance medical organizations (IMO) in the market etc. Data that were obtained in the course of complex multi-field research served as a basis for elaborating advanced programs for the promotion of VMI in the territory of Orenburg Region as well as for working out proposals targeted at optimizing the VMI performance in the market of medical services.