汽油尾气对小鼠肺脏的氧化应激和遗传毒性作用

[目的]探讨汽油尾气对小鼠肺的氧化应激作用和对脏器系数以及组织细胞DNA的影响。[方法]将汽油尾气有机提取物以0、8.5、17.0、34.0 L/kg的剂量经气管滴注染毒昆明种小鼠,每5 d染毒1次,共3次,末次染毒24 h后处死小鼠,称量体重和肺脏重量,测定肺组织内超氧化物岐化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性和丙二醛(MDA)含量;并用彗星实验检测肺组织细胞中DNA的损伤程度。[结果]各剂量组小鼠肺脏脏器系数的增加与对照组相比差异无统计学意义(P﹥0.05);各剂量组SOD和GSH-Px酶活力明显降低,MDA含量则显著升高(P﹤0.05),且染毒剂量与酶活力、MDA含量均呈剂量-反应关系(r值分别为-0.98、-0.959和0.97,P均小于0.05)。在17.0、34.0 L/kg组,肺组织细胞的拖尾率和尾长较对照组明显增加(P﹤0.05)。[结论]汽油尾气可促进小鼠肺组织的氧化应激和诱导肺细胞DNA的损伤。     

乙苯染毒对大鼠肺的氧化应激损伤及病理的影响

目的 观察亚慢性吸人乙苯染毒对大鼠肺组织氧化应激损伤和组织病理结构、细胞超微结构的影响.方法 将40只健康3周龄SPF级SD雄性大鼠随机分为4组,分别为对照组(新鲜空气)和低(433.5 mg/m3)、中(4335 mg/m3)和高(6500 mg/m3)剂量乙苯染毒组,每组10只.每天染毒6h,每周5d,连续染毒13周.检测肺组织中还原型谷胱甘肽(GSH)、谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活力和丙二醛(MDA)含量并进行超微结构和病理学观察.结果 乙苯染毒大鼠肺组织出现肺泡壁毛细血管充血,肺泡间纤维组织增生、增厚等病理变化,超微结构的变化主要表现为肺组织大部分血管内皮细胞肿胀,胞质厚度增加.与对照组相比,各染毒组大鼠肺组织MDA含量均明显升高,差异有统计学意义(P＜0.05).中剂量组和高剂量组大鼠肺组织GSH和GSH-Px含量均明显低于对照组和低剂量组,差异有统计学意义(P＜0.05).与对照组相比,各剂量组大鼠肺组织SOD和CAT活力呈先升高后降低趋势;与低剂量组比较,中剂量组和高剂量组大鼠肺组织SOD活力和CAT含量均明显降低,差异有统计学意义(P均＜0.05).结论 亚慢性吸入乙苯染毒可诱导大鼠肺组织氧化应激损伤及组织病理结构、组织细胞超微结构的改变.     

金属硫蛋白对镍铬联合染毒小鼠肝脏损伤的拮抗作用

目的研究硫酸镍+重铬酸钾联合染毒对小鼠肝脏损伤的影响及金属硫蛋白(MT)的拮抗作用。方法将50只健康SPF级昆明小鼠按体重随机分为5组,分别为溶剂对照组(生理盐水)、镍铬(1.0 mg/kg硫酸镍+0.5 mg/kg重铬酸钾)联合染毒组和低、中、高剂量MT保护(1.0 mg/kg硫酸镍+0.5 mg/kg重铬酸+5.0、10.0、20.0 mg/kg MT)组,每组10只,雌雄各半。采取灌胃方式进行染毒,染毒容量为10 ml/kg,每天1次,连续染毒21 d。检测小鼠丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、γ-谷氨酰转肽酶(GGT)活力及肝组织超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活力和丙二醛(MDA)、谷胱甘肽(GSH)含量。结果与溶剂对照组比较,镍铬联合染毒组小鼠血清AST、ALT、GGT的活力均增高,差异均有统计学意义(P0.05)。各剂量MT保护组小鼠血清AST、ALT、GGT的活力均低于镍铬联合染毒组,差异均有统计学意义(P0.05);且随着MT染毒剂量的升高,MT保护组小鼠血清AST、ALT、GGT的活性均呈下降趋势。与溶剂对照组比较,镍铬联合染毒组小鼠肝组织SOD、GSH-Px活力和GSH含量均下降,而MDA含量升高,差异均有统计学意义(P0.05)。与镍铬联合染毒组比较,各剂量MT保护组小鼠肝组织SOD、GSH-Px活力和GSH含量均升高,而MDA含量均降低,差异均有统计学意义(P0.05),且随着MT染毒剂量的升高,MT保护组小鼠肝组织SOD、GSH-Px活力和GSH含量均呈上升趋势,而MDA含量呈下降趋势。结论 MT对镍铬联合染毒所致小鼠肝脏损伤有较好的拮抗作用,其作用机制可能与MT抗氧化作用有关。     

PM_(2.5)诱导小鼠肺氧化应激损伤及硒的拮抗作用

目的探讨不同剂量PM_(2.5)诱导小鼠肺氧化应激及硒的保护作用。方法将清洁级昆明小鼠50只随机分为对照组、低剂量组(30μl 0.2μg/μl PM_(2.5)悬液)、中剂量组(30μl 1.2μg/μl PM_(2.5)悬液)、高剂量组(30μl 2.3μg/μl PM_(2.5)悬液)、硒+高剂量组,每组10只,其中对照组气管滴注生理盐水,各染毒组气管滴注不同浓度PM_(2.5),硒+高剂量组在进行硒预处理(35μg/kg)后气管滴注30μl 1.2μg/μl PM_(2.5)悬液。24 h后处死动物,取血清、肺泡灌洗液及肺组织,检测超氧化物歧化酶(SOD)、谷胱甘肽(GSH)、氧化型谷胱甘肽(GSSG)、谷胱甘肽过氧化物酶(GSH-Px)和丙二醛(MDA)水平。结果染毒后,中、高剂量组小鼠血清中GSH、SOD及GSH-Px水平低于对照组,高剂量组MDA、GSSG/GSH值高于对照组;硒预处理后,SOD活力高于高剂量组,差异有统计学意义(P0.05)。高剂量组小鼠肺灌洗液中SOD、GSH及GSH-Px水平低于对照组,各剂量组MDA含量高于对照组;硒预处理后,SOD活力高于高剂量组,MDA含量低于高剂量组,差异有统计学意义(P0.05)。中、高剂量组小鼠肺组织匀浆中GSH、GSH-Px水平低于对照组,GSSG/GSH值高于对照组,高剂量组SOD活力低于对照组;硒预处理后,GSH、SOD、GSH-Px水平高于高剂量组,GSSG/GSH值低于高剂量组,差异有统计学意义(P0.05)。结论不同剂量的PM_(2.5)可诱导小鼠出现不同程度的氧化应激,硒可在一定程度上拮抗其造成的氧化应激。     

丙烯腈染毒致小鼠脑组织氧化损伤的研究

目的探讨丙烯腈(acrylonitrile,AN)染毒小鼠脑组织中氧化损伤指标的改变。方法将200只成年(6～8周龄)健康SPF级昆明雄性小鼠按体重随机分为4组,分别为阴性对照(生理盐水)组和低(1.25 mg/kg)、中(2.5 mg/kg)、高(5 mg/kg)剂量丙烯腈染毒组,每组50只。采用腹腔注射方式进行染毒,染毒容量为10 ml/kg,每天1次,连续染毒5 d。于初次染毒后的第7、14、21、28、35天测定脑组织中谷胱甘肽(GSH)和丙二醛(MDA)的含量以及谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和胆碱酯酶(ChE)的活力。结果与阴性对照组比较,第28天中、高剂量丙烯腈染毒组小鼠脑组织中GSH含量均下降,第7、21天各剂量丙烯腈染毒组小鼠脑组织中的MDA含量以及第21天低、高剂量丙烯腈染毒组小鼠脑组织GSH-Px活力和低、中、高剂量丙烯腈染毒组小鼠脑组织CAT活力均升高,差异均有统计学意义(P0.05)。各丙烯腈染毒组小鼠脑组织SOD和ChE活力间比较,差异均无统计学意义。结论丙烯腈染毒可诱发脑组织的氧化损伤。     

番茄红素对溴代苯诱导小鼠脂质过氧化损伤的拮抗作用

目的探讨番茄红素对溴代苯诱导小鼠脂质过氧化损伤的拮抗作用。方法将50只健康成年SPF级昆明雄性小鼠随机分为5组,即对照组、溴代苯模型组和低、中、高剂量番茄红素+溴代苯组,每组10只。低、中、高剂量番茄红素+溴代苯组小鼠经口灌胃浓度分别为0.33、0.67和2.00 g/L的番茄红素溶液,对照组和溴代苯模型组灌胃等体积的溶剂(含98%水、0.8%甘油、0.7%无水乙醇、0.5%玉米油),染毒容量为0.02 ml/g,每天1次,连续染毒30 d;番茄红素暴露结束0.5 h后,测定红细胞超氧化物歧化酶(SOD)活力、全血谷胱甘肽过氧化物酶(GSH-Px)活力及总抗氧化能力(T-AOC)。番茄红素暴露结束3 h后,除对照(橄榄油)组外,其余4组立即一次性灌胃染毒0.4 mg/kg的溴代苯溶液,染毒容量为0.01 ml/g,22 h后,测定肝脏中丙二醛(MDA)含量和SOD、GSH-Px活力及T-AOC。结果番茄红素暴露后,与溴代苯模型组相比,中、高剂量番茄红素+溴代苯组小鼠红细胞SOD活力、全血GSH-Px活力及全血T-AOC显著升高(P<0.05,P<0.01);溴代苯染毒后,与溴代苯模型组相比,中、高剂量番茄红素+溴代苯组小鼠肝脏中SOD活力、GSH-Px活力及T-AOC明显增强(P<0.05,P<0.01),MDA含量显著下降(P<0.05,P<0.01)。随着番茄红素暴露剂量的升高,小鼠肝脏中MDA含量呈下降趋势,而血液及肝脏中SOD、GSH-Px活力及T-AOC呈上升趋势。结论番茄红素对溴代苯引起的小鼠脂质过氧化损伤具有一定的拮抗作用。     

Antiagonizing Effect of Lycopene on Bromobenzene-induced Lipid Peroxidation in Mice

目的 探讨番茄红素对溴代苯诱导小鼠脂质过氧化损伤的拮抗作用.方法 将50只健康成年SPF级昆明雄性小鼠随机分为5组,即对照组、溴代苯模型组和低、中、高剂量番茄红素+溴代苯组,每组10只.低、中、高剂量番茄红素+溴代苯组小鼠经口灌胃浓度分别为0.33、0.67和2.00 g/L的番茄红素溶液,对照组和溴代苯模型组灌胃等体积的溶剂(含98％水、0.8％甘油、0.7％无水乙醇、0.5％玉米油),染毒容量为0.02 ml/g,每天1次,连续染毒30d;番茄红素暴露结束0.5 h后,测定红细胞超氧化物歧化酶(SOD)活力、全血谷胱甘肽过氧化物酶(GSH-Px)活力及总抗氧化能力(TAOC).番茄红素暴露结束3h后,除对照(橄榄油)组外,其余4组立即一次性灌胃染毒0.4mg/kg的溴代苯溶液,染毒容量为0.01 ml/g,22 h后,测定肝脏中丙二醛(MDA)含量和SOD、GSH-Px活力及T-AOC.结果 番茄红素暴露后,与溴代苯模型组相比,中、高剂量番茄红素+溴代苯组小鼠红细胞SOD活力、全血GSH-Px活力及全血T-AOC显著升高(P＜0.05,P＜0.01);溴代苯染毒后,与溴代苯模型组相比,中、高剂量番茄红素+澳代苯组小鼠肝脏中SOD活力、GSH-Px活力及T-AOC明显增强(P＜0.05,P＜0.01),MDA含量显著下降(P.＜0.05,P＜0.01).随着番茄红素暴露剂量的升高,小鼠肝脏中MDA含量呈下降趋势,而血液及肝脏中SOD、GSH-Px活力及T-AOC呈上升趋势.结论 番茄红素对溴代苯引起的小鼠脂质过氧化损伤具有一定的拮抗作用.     

纳米氧化石墨烯一次性染毒对小鼠肝脏的急性氧化损伤作用

目的探讨纳米氧化石墨烯(nano-GO)对小鼠肝脏的急性氧化损伤作用。方法将80只健康清洁级ICR小鼠随机分为对照(高纯水)组和0.35 mg/kg(1/16 LD50)、0.70 mg/kg(1/8 LD50)、1.40 mg/kg(1/4 LD50)nano-GO染毒组,每组20只,雌雄各半。采用1次性尾静脉注射染毒,染毒容量为10 ml/kg。分别于注射3、15 d后,检测小鼠肝脏组织超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活力和丙二醛(MDA)含量。结果染毒3 d后,与对照组比较,各剂量nano-GO染毒组雌性小鼠和0.35 mg/kg nano-GO染毒组雄性小鼠肝脏的MDA含量及各剂量nano-GO染毒组小鼠肝脏的GSH-Px活力以及0.35、0.70 mg/kg nano-GO染毒组雄性小鼠肝脏的SOD活力均升高,0.70、1.40 mg/kg nano-GO染毒组雄性小鼠肝脏MDA含量和0.35、0.70 mg/kg nano-GO染毒组雌性小鼠肝脏的SOD活力均下降,差异均有统计学意义(P0.05)。染毒15 d后,与对照组比较,各剂量nano-GO染毒组小鼠肝脏的SOD活力升高,0.70 mg/kg和1.40 mg/kg nano-GO染毒组小鼠肝脏的GSH-Px活力下降,差异均有统计学意义(P0.05);而各剂量nano-GO染毒组小鼠肝脏的MDA含量均无明显改变。结论一次性尾静脉注射nano-GO后,肝脏可产生脂质过氧化作用,干扰小鼠肝脏抗氧化酶的活力。     

包头市水源水及其自来水中有机提取物对小鼠氧化性损伤及遗传毒性研究

目的 探讨黄河包头段水源水及其自来水中有机提取物对小鼠的氧化性损伤及遗传毒性影响.方法 于2005年4月,采集黄河包头段上、中、下游水源水及其自来水.将昆明种健康小鼠按体重随机分成14组,每组10只,雌、雄各半.分别设自来水组、上游水组、中游水组和下游水组[每组中分低(2 L/ml)、中(5 L/ml)、高剂量组(10 L/ml)]、阴性对照组(DMSO)、阳性对照组(环磷酰胺).染毒组和阴性对照组按0.01 ml/g对小鼠进行灌胃,每天灌胃1次,连续5 d.末次染毒6 h后,测定各组小鼠肝脏、肾脏中超氧化物岐化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活力以及丙二醛(MDA)的含量.计算小鼠骨髓细胞微核率.结果 中、下游水染毒组肝组织SOD和GSH-Px活力均随染毒剂量增加呈下降趋势;4种水样染毒组肾组织SOD活力在低剂量组较对照组升高,然后呈下降趋势;3种水源水染毒组肾组织GSH-Px活力随染毒剂量增加呈下降趋势;肝肾组织MDA含量随染毒剂量增加呈上升趋势,且存在不同程度的统计学意义.除自来水低剂量组外,各染毒组的微核率均高于阴性对照组,低于阳性对照组;在相同剂量组中,水源水染毒的小鼠骨髓细胞微核率均高于自来水,差异有统计学意义(P＜0.01).且中游水染毒的小鼠骨髓细胞微核率最高.结论 黄河包头段水源水及其自来水中有机提取物对小鼠具有氧化性损伤作用和潜在的遗传毒性作用.     

纳米硫化铅对大鼠海马及皮质氧化损伤作用的研究

目的探讨纳米硫化铅对大鼠海马及皮质的氧化损伤作用。方法清洁级SD雄性大鼠60只,随机分为3组,即对照组、纳米硫化铅低、高剂量组,低、高剂量组分别气管灌注15、30mg/kg粒径20nm的硫化铅混悬液1ml,每周1次,连续染毒3个月后测定3个组大鼠体质量变化;检测大鼠血清、海马及皮质中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活力和丙二醛(MDA)含量。结果染毒组大鼠血清、海马及皮质中SOD、GSH-Px的活力及MDA含量分别与对照组比较,差异均有统计学意义(P<0.05)。染毒组大鼠血清、海马及皮质中SOD、GSH-Px活力均降低,MDA含量增高。结论纳米硫化铅可能引起海马及皮质中SOD、GSH-Px活力降低,MDA含量增加,可导致海马及皮质抗氧化能力减弱。     

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.     

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.     

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.     

Occupational health hazards in mining: an overview

This review article outlines the physical, chemical, biological, ergonomic and psychosocial occupational health hazards of mining and associated metallurgical processes. Mining remains an important industrial sector in many parts of the world and although substantial progress has been made in the control of occupational health hazards, there remains room for further risk reduction. This applies particularly to traumatic injury hazards, ergonomic hazards and noise. Vigilance is also required to ensure exposures to coal dust and crystalline silica remain effectively controlled.     

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.     

Manufacture and use of nanomaterials: current status in the UK and global trends

This paper provides an overview of the production and use of nanomaterials (NMs), particularly in the UK. Currently, relatively few companies in the UK are identifiable as NM manufacturers, the main emphasis being the bulk markets in metals and metal oxides, and some niche markets such as carbon nanotubes and quantum dots. NM manufacturing in the UK does not reflect the global emphasis on fullerenes, nanotubes and fibres. Some assumptions have been made about the types of NM that are likely to be imported into the UK, which currently include fullerenes, modified fullerenes and other carbon-based NMs including nanotubes. Many university departments, spin-offs and private companies have developed processes for the manufacture of NMs but may only be producing small quantities for research and development (R&D) purposes. However, some have the potential to scale up to produce large quantities. The nanotechnology industry in the UK has strong R&D backup from universities and related institutions. This review has covered R&D trends at such institutions, and appropriate information has been added to a searchable database. While several companies are including NMs in their products, only a few (e.g. manufacturers of paints, coatings, cosmetics, catalysts, polymer composites) are using nanoparticles (NPs) in any significant quantities. However, this situation is likely to change rapidly. There is a need to collect more information about exposure to NPs in both manufacturing and user scenarios. As the market grows, and as manufacturers switch from the micro- to the nanoscale, the potential for exposure will increase. More research is required to quantify any risks to workers and consumers.     

Investigating clusters in the workplace and beyond

Clusters of disease are common and occur in the workplace and in the general community. They often arouse considerable concern among the population. Investigations have sometimes lead to exciting new knowledge, but in general the investigation of clusters is difficult and often unrewarding, especially for community clusters. In the workplace, investigations are more likely to find associations and even new causes, but still many clusters remain enigmatic. Despite this, there are many reasons for investigating clusters, including allaying community concern and identifying uncontrolled exposures. A structure for investigating clusters in the workplace is suggested.