番茄红素对高同型半胱氨酸血症大鼠血管内皮功能的影响和机制研究

目的研究番茄红素(Lyc)预防高同型半胱氨酸血症(HHcy)致大鼠动脉粥样硬化(AS)的作用机制。方法50只SD雄性大鼠分为正常对照组(NC),HHcy对照组n(HC),HHcy+低(HL1)、中(HL2)、高剂量Lyc组(HL3)。NC组给予AOAC配方饲料,其余各组则给予在AOAC配方基础上添加3%L-蛋氨酸的饲料。HL1、HL2、HL3组按体重每日分别给予Lyc10、15、20mg/kgbw,实验期12w。分析血清Hcy、NO、一氧化氮合酶(NOS)、内皮素-1(ET-1),丙二醛(MDA)、·OH、H2O2,血管细胞粘附分子-1(VCAM-1)、单核细胞趋化因子-1(MCP-1)、白介素-8(IL-8)含量。处死动物,取腹主动脉做NF-κB测定和病理学检查。结果除了NC组外,HHcy各组大鼠血清Hcy含量均随时间延长而显著提高;HC组NO含量显著低于NC组,而ET-1含量显著高于NC组,HL2和HL3组NO含量显著高于HC组,而ET-1含量则明显低于HC组,各组间NOS含量无明显差异。病理学检查显示,HC组和HL1组主动脉内膜中有泡沫细胞聚集,有脂肪颗粒沉着,HL2组、HL3组和NC组主动脉内膜完整,无泡沫细胞和脂肪颗粒。HC和HL1组血清MDA和H2O2含量显著高于NC组,HL2和HL3组则明显低于HC组,HL2和HL3组H2O2含量还显著低于HL1组。与HC组相比,HL2和HL3组血清·OH含量显著降低;HC组VCAM-1、MCP-1和IL-8含量显著高于NC组,HL1、HL2和HL3组则明显低于HC组;HC组NF-κB的表达显著高于NC组,HL1、HL2和HL3组则明显低于HC组。结论Lyc可以通过直接淬灭活性氧,抑制NF-κB的激活,减少炎性因子的表达,来改善血管内皮功能,阻止AS的发生。     

高强度运动对高同型半胱氨酸血症大鼠抗氧化和内皮功能的影响

目的探讨高强度间歇训练(HIIT)对高同型半胱氨酸血症(HHcy)大鼠抗氧化和血管内皮功能的影响。方法 35只大鼠分为对照组(n=8)和实验组(n=27),实验组大鼠用含3%蛋氨酸饲料喂养,持续8周,构建HHcy大鼠模型。建模成功后,实验组随机分为模型组、叶酸组和叶酸+HIIT组,治疗16周。检测各组大鼠血清同型半胱氨酸(Hcy)、血浆丙二醛(MDA)、羟自由基(OH-)、总抗氧化能力(T-AOC)和谷胱甘肽过氧化物酶(GSH-PX)、超氧化物歧化酶(SOD)活性、一氧化氮(NO)、一氧化氮合酶(NOS)及内皮素1(ET-1)水平;取大鼠腹主动脉做病理学检查。结果治疗16周后,叶酸+HIIT组大鼠血清Hcy水平与对照组比较差异无统计学意义(P0.05),血清Hcy水平依次为模型组(23.95±3.35)μmol/L,叶酸组(8.73±0.60)μmol/L,叶酸+HIIT组(6.19±0.34)μmol/L;叶酸+HIIT组MDA较叶酸组和模型组下降(P0.05),与对照组比较差异无统计学意义(P0.05);叶酸组和叶酸+HIIT组SOD活力和GSH-PX含量较模型组升高(P0.05),叶酸+HIIT组较叶酸组升高(P0.05);叶酸组ET-1、NOS和NO水平与对照组比较,差异均有统计学意义(P0.05),而叶酸+HIIT组ET-1和NOS水平与对照组比较,差异均无统计学意义(P0.05);叶酸+HIIT组大鼠血管组织形态学观察可见轻度动脉硬化病变。结论高强度间歇训练联合叶酸治疗可以降低HHcy大鼠血清Hcy水平,改善氧化应激状态,减轻内皮功能损伤,且效果优于单纯叶酸治疗。     

茶色素对Hcy致血管内皮损伤拮抗作用

目的 探讨同型半胱氨酸(Hcy)致血管内皮细胞的损伤作用及茶色素的拮抗作用.方法 体外培养动脉内皮细胞,随机分为6组;培养48 h后,应用四甲基偶氮噻唑蓝法(MTT)检测细胞生长情况,取培养液测定一氧化氮(NO)、一氧化氮合酶(NOS)、内皮素-1(ET-1)和超氧化歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活力及丙二醛(MDA)含量.结果 Hcy组细胞生长抑制率为30.70%,中、高剂量茶色素干预组细胞抑制率分别下降为13.62%和11.08%;NO含量对照组为91.33 μmol/L,Hcy组为45.67 μmol/L;ET-1含量对照组为1.39 ng/mL,Hcy组为7.18 ng/mL,给予茶色素干预后,NO含量升高,ET-1含量降低(P<0.05);MDA含量对照组为4.27 nmol/mL,Hcy组为8.51 nmol/mL;SOD活性对照组为18.72 U/mL,Hcy组为8.73 U/mL,给予茶色素干预后,MDA含量降低,SOD活性和GSH-Px活性升高(P<0.05).结论 茶色素有拮抗高同型半胱氨酸致血管内皮细胞损伤的作用,其机制可能与抗氧化和恢复细胞因子表达有关.     

氟和砷联合染毒对大鼠在新环境中探究行为的影响及机制

目的 探讨氟、砷单独及其联合染毒对大鼠在新环境中的探究行为的影响及机制.方法 将96只健康初断乳SPF级SD大鼠随机分为对照(蒸馏水)组和NaF(120 mg/L)染毒组、亚砷酸钠(70 mg/L)染毒组及NaF(120 mg/L)+亚砷酸钠(70 mg/L)染毒组,每组24只,雌雄各半.采用饮水方式连续染毒3个月.采用旷场试验测试大鼠在新环境中的探究行为,检测大鼠血清和海马组织匀浆中总抗氧化能力(T-AOC)水平和丙二醛(MDA)、一氧化氮(NO)含量及超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)和一氧化氮合酶(NOS)活力.结果 NaF+亚砷酸钠染毒组大鼠旷场试验总得分低于对照组、NaF和亚砷酸钠染毒组(P＜0.01).NaF、亚砷酸钠和NaF+亚砷酸钠染毒组中央格停留时间均长于对照组(P＜0.01).与对照组比较,NaF、亚砷酸钠和NaF+亚砷酸钠染毒组大鼠血清T-AOC水平及亚砷酸钠染毒组和NaF+亚砷酸钠染毒组血清SOD、GSH-Px活力降低,MDA含量升高(P＜0.05,P＜0.01).与NaF染毒组比较,亚砷酸钠和NaF+亚砷酸钠染毒组大鼠血清中T-AOC水平和GSH-Px活力降低(P＜0.05,P＜0.01).与对照组比较,NaF、亚砷酸钠和NaF+亚砷酸钠染毒组大鼠海马组织匀浆中T-AOC水平均降低(P＜0.01).与亚砷酸钠染毒组比较,对照组、NaF染毒组和NaF+亚砷酸钠染毒组大鼠海马组织匀浆中GSH-Px的活力均较高(P＜0.01).与NaF+亚砷酸钠染毒组比较,NaF、亚砷酸钠染毒组和对照组大鼠海马组织匀浆中MDA含量均较低(P＜0.01).与对照组比较,NaF和NaF+亚砷酸钠染毒组大鼠血清NO含量以及NaF、亚砷酸钠和NaF+亚砷酸钠染毒组大鼠血清中NOS活力及海马组织中NO含量、NOS活力均下降(P＜0.05,P＜0.01).结论 氟、砷及其联合作用可损害大鼠在新环境中的探究行为,其机制可能与海马组织氧化损伤及NO含量和NOS活力降低有关.     

慢性轻度高同型半胱氨酸血症对大鼠NO影响

目的观察蛋氨酸强化或叶酸缺乏膳食诱导的慢性高同型半胱氨酸血症(HHcy)大鼠体内一氧化氮(NO)的生成和代谢转化情况,从而探讨同型半胱氨酸(Hcy)致动脉粥样硬化(AS)中NO的可能作用。方法36只SD大鼠,按体重随机分为3组;对照组、高蛋氨酸组和叶酸缺乏组,分别饲以美国营养学会1993年公布的生长期啮齿类动物纯化配方饲料(AIN-93 G饲料)及强化1%L-蛋氨酸或不含叶酸的AIN-93 G饲料。14周后测定血浆总Hcy,血清NO、丙二醛(MDA)等含量,主动脉一氧化氮合酶(NOS)活性及主动脉硝基化酪氨酸(NT)含量。结果高蛋氨酸和叶酸缺乏膳食均可升高血浆Hcy水平,各组的NO含量及NOS活性差异无统计学意义,但2个HHcy实验组的MDA含量和主动脉NT表达量均高于对照组。结论膳食诱导的慢性HHcy大鼠体内NO总量及主动脉NOS活性并没有变化;氧化应激生成过氧化亚硝基阴离子(ONOO-)等反应使NO的生物可用性降低。     

沙棘油和五味子乙素对镉致大鼠急性肝损伤的影响

将实验用Wistar大鼠32只,按体重随机分为4组,第1组为对照组,第2组为单纯染镉组,第3组和第4组为沙棘油(SBO)和五味子乙素(Sch B)预处理组,测定血清乳酸脱氢酶(LDH)、丙氨酸氨基转移酶(ALT)活性,肝丙二醛(MDA)、谷胱甘肽(GSH)含量及谷胱甘肽过氧化酶(GSH-Px)、超氧化物歧化酶(SOD)活性.与对照组比较,单纯染镉组的血清LDH、ALT活性及肝MDA、GSH含量显著升高,肝GsH-Px、SOD活性显著降低(P<0.01).与单纯染镉组比较,SBO干预组的血清LDH、ALT活性、肝MDA、GSH含量显著降低,GSH-Px、SOD活性显著升高(P<0.01);Sch B干预组的血清LDH、ALT活性及肝MDA、GSH含量明显降低(P<0.01),GSH-Px活性升高,差异有统计学意义(P<0.05).提示SBO和Sch B对镉急性肝氧化损伤具有一定的拮抗作用.     

急性脑梗死患者血浆同型半胱氨酸水平及意义

目的分析血浆同型半胱氨酸(Hcy)水平与脑梗死发病和病情程度的关系。方法选择136例急性脑梗死患者和70例对照,采用荧光偏振免疫分析法测定其空腹血浆Hcy浓度。结果脑梗死组血浆Hcy高于对照组(P<0.01)。脑梗死组18.4%合并高Hcy血症(HHcy),对照组4.3%合并高Hcy血症(P<0.01)。轻、中、重型脑梗死组的血浆Hcy呈依次升高趋势(P<0.05)。15例合并HHcy的患者接受了维生素治疗,2周后,血浆Hcy水平明显下降(P<0.01),叶酸和维生素B12则显著升高(P<0.05)。结论轻-中度HHcy在脑梗死患者中是脑梗死的独立危险因素;病情越重,血浆Hcy水平越高;维生素治疗能有效降低血浆Hcy水平。     

海带多糖对超重环境微波辐射大鼠氧化损伤的抑制

为探讨海带多糖对超重环境下微波辐射大鼠氧化损伤的影响,将18只雄性Wistar大鼠随机分为3组,每组6只,制作大鼠6 g超重环境下微波(200 mW/cm2,5min)损伤模型(模型组),并灌胃给予20 mg/ml海带多糖(海带多糖组)。结果显示,模型组大鼠血清一氧化氮(NO)、抗超氧阴离子活力、过氧化氢酶(CAT)、一氧化氮合酶(NOS)、还原型谷胱甘肽(GSH)、谷胱甘肽过氧化物酶(GSH-Px)低于对照组,海带多糖组大鼠上述指标高于模型组;模型组大鼠肝匀浆中CAT、GSH-Px和GSH低于对照组,NOS高于对照组;海带多糖组大鼠肝匀浆中CAT高于模型组,NOS低于模型组,上述差异均有统计学意义(P0.05)。提示海带多糖对超重环境下微波损伤的抑制作用可能与CAT、GSH-Px、GSH升高有关。     

白藜芦醇对衰老小鼠氧化应激和血清同型半胱氨酸的影响

目的观察白藜芦醇(resveratrol,Res)对D-半乳糖(D-galactose,D-gal)诱导的小鼠血清同型半胱氨酸(homocysteine,Hcy)和氧化应激相关指标的影响。方法 48只小鼠随机分为4组:基础对照组、衰老模型组、Res低剂量组(22.5 mg/kg)、Res高剂量组(45 mg/kg),基础对照组每日经颈部皮下注射生理盐水,其余三组经颈部皮下注射D-gal溶液。同时,基础对照组和衰老模型组每日经灌胃给予羧甲基纤维素钠溶液,而其余2组每日经灌胃给予Res羧甲基纤维素钠溶液。16周后检测小鼠血清Hcy水平;血清和肝脏中超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)、总抗氧化能力(total antioxidant capacity,T-AOC)和丙二醛(malondialdehyde,MDA)水平。结果与基础对照组相比,衰老模型组小鼠血清Hcy水平显著升高(P0.05),且其血清和肝脏SOD、GSH-Px和T-AOC显著降低(P0.05),而MDA水平则显著升高(P0.05),表明造模成功。与衰老模型组比较,两种剂量的Res均可显著降低小鼠血清Hcy水平(P0.05),显著升高其血清和肝脏SOD、GSH-Px和T-AOC水平(P0.05),而显著降低其血清和肝脏MDA水平(P0.05)。结论不同剂量的Res能够预防D-gal诱导的小鼠氧化应激水平和血清Hcy水平升高,有一定的抗衰老作用。     

氧化应激反应在矽肺发病中的作用

目的观察矽肺患者氧化应激指标的变化,探讨矽肺发生发展的机制。方法对100例对照组、200例接尘组,32例矽尘作业观察对象(原诊断0+患者)组及130例矽肺组分别测定血清中氧化应激指标:超氧化物歧化酶(SOD)、一氧化氮(NO)、谷胱甘肽过氧化物酶(GSH-Px)、总抗氧化能力(T-AOC)、一氧化氮合酶(NOS)及脂质过氧化物丙二醛(MDA)含量。结果与对照组比较,接尘组与矽肺组NO水平、GSH-Px活力均明显升高,SOD水平明显降低(P0.05,P0.01);与对照组、接尘组比较,矽肺组T-AOC、NOS、MDA均明显升高(P0.05,P0.01);矽肺组较接尘组GSH-Px活力明显升高(P0.01)。与观察对象组和Ⅰ期矽肺组比较,Ⅲ期矽肺组GSH-Px活力明显升高(P0.05)。Pearson相关分析显示血清中GSH-Px水平与矽肺分期、分组、接尘工龄、工种呈显著正相关(P0.01)。结论机体氧化和抗氧化系统的失衡与矽肺的发生发展有关;对氧化应激指标的监测有利于预测矽肺发病和评估预后。     

Calcium intake in the elderly: validation of a dietary questionnaire

Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.     

The human drama of genetics: 'hard' and 'soft' media representations of inherited breast cancer

This paper examines media coverage of 'breast cancer genetics', and explores its implications for public understanding. We present a content analysis of coverage in British newspapers and look at a variety of popular forms, including women's magazines, television soap opera and radio drama. Genetic/inherited risk receives a great deal of coverage across a wide range of media formats and outlets. Much of this attention has focused on individuals from 'high risk families' and dilemmas around prophylactic mastectomies. Through examining media coverage, combined with interviews with media personnel and their sources, we show why this story proved so attractive to the media and highlight the different production values which influence coverage. Finally, we introduce preliminary findings from focus group discussions to demonstrate how such 'human interest' framing has engaged audience attention and influenced public understandings. The paper concludes by highlighting the implications for analysing, predicting, and engaging with, media representations of science.     

Worker education in the primary prevention of occupational dermatoses

This paper reports the evaluation of a skin care education programmeconducted on a fine chemicals manufacturing site where over1,000 employees are located. Approximately 60% are involvedin chemical manufacture. Over a 12 month period production staffreceived training in prevention of occupational dermatoses linkedto a site-wide poster initiative. The incidence of new casesof occupational dermatoses fell from 0.055 (70 cases in 1,277employees) to 0.021 (27 cases in 1,277 employees) before andafter the intervention respectively (p<0.0001). After otherfactors such as chemicals handled, observer bias and changesin reporting related to socioeconomic climate were taken intoaccount it is concluded that this study demonstrates the importanceof worker education as a tool for primary prevention of disease.Training materials such as video and poster presentations maybe effectively used in the chemical manufacturing industry asan adjunct to prevention and control of exposure to substanceshazardous to the skin. Such methods may also be used in otherindustries where there are significant risks of dermatoses.     

Regional Variation in Travel-related Illness acquired in Africa,March 1997–May 2011

To understand geographic variation in travel-related illness acquired in distinct African regions, we used the GeoSentinel Surveillance Network database to analyze records for 16,893 ill travelers returning from Africa over a 14-year period. Travelers to northern Africa most commonly reported gastrointestinal illnesses and dog bites. Febrile illnesses were more common in travelers returning from sub-Saharan countries. Eleven travelers died, 9 of malaria; these deaths occurred mainly among male business travelers to sub-Saharan Africa. The profile of illness varied substantially by region: malaria predominated in travelers returning from Central and Western Africa; schistosomiasis, strongyloidiasis, and dengue from Eastern and Western Africa; and loaisis from Central Africa. There were few reports of vaccine-preventable infections, HIV infection, and tuberculosis. Geographic profiling of illness acquired during travel to Africa guides targeted pretravel advice, expedites diagnosis in ill returning travelers, and may influence destination choices in tourism.     

深圳公立医院管理体制改革制度设计

深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.     

The design of hazard risk assessment matrices for ranking occupational health risks and their application in mining and minerals processing

Two hazard risk assessment matrices for the ranking of occupational health risks are described. The qualitative matrix uses qualitative measures of probability and consequence to determine risk assessment codes for hazard-disease combinations. A walk-through survey of an underground metalliferous mine and concentrator is used to demonstrate how the qualitative matrix can be applied to determine priorities for the control of occupational health hazards. The semi-quantitative matrix uses attributable risk as a quantitative measure of probability and uses qualitative measures of consequence. A practical application of this matrix is the determination of occupational health priorities using existing epidemiological studies. Calculated attributable risks from epidemiological studies of hazard-disease combinations in mining and minerals processing are used as examples. These historic response data do not reflect the risks associated with current exposures. A method using current exposure data, known exposure-response relationships and the semi-quantitative matrix is proposed for more accurate and current risk rankings.     

Self-reported health problems among Swedish miners one year after unemployment

Unemployment is considered to be a public health concern sincedeterioration in the health of the unemployed is often anticipated.However, for some groups, such as miners, unemployment mightimprove health due to a cessation of potentially harmful occupationalexposures. This study evaluates the health of 79 miners in oneSwedish iron-ore mine, and 226 age-matched controls from thegeneral population, during one year after the closure of themine. The participants received a questionnaire regarding medicalhistory and subjective symptoms at the beginning of the studyperiod, and after one year. Statistically significant negativeeffects on self-reported health attributable to unemploymentwere not found, although neuropsychiatric symptoms were morecommon among the unemployed miners. The miners reported a statisticallysignificant improvement in grip force (p=0.031). They had asignificantly higher prevalence of symptoms associated withmining related exposures when compared with the population controls;pain in the upper extremities [relative risk (RR)=2.27, 95%confidence interval (Cl)=1.44–3.59), back pain (RR=1.84;Cl=1.237–2.75), vasospastic disease of the fingers (RR=2.05;Cl=1.18–3.57) and obstructive respiratory symptoms (attacksof dyspnea and wheezing: RR=3.67; Cl=1.167–11.6).     

Excès de cas humains et animaux de tularémie en France au cours de l’hiver 2007–2008 : émergence ou phénomène isolé ?

Context

Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008.

Methods

Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results.

Results

In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent.

Conclusion

An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.     

Effects of nitrogen dioxide on red blood cells of rats: Changes in components of red cell membranes during in vivo exposure to NO2

Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO₂) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO₂. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO₂ at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO₂ gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO₂ also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO₂.