餐具洗洁精对小鼠肝脏解毒功能的影响

[目的]为了探讨洗涤剂对肝脏内不同抗氧化酶以及解毒系统Ⅰ阶段重要的酶7-乙氧基。3。异吩恶唑酮．脱乙基酶(皿oD)的影响。[方法]4周龄的小鼠饮用不同浓度的餐具洗洁精染毒，测定其肝脏谷胱甘肽还原酶(GR)、谷胱甘肽过氧化物酶(GSH-Px)EROD。[结果]≥31mg／L各浓度组的GR活力在染毒第4天和第8天时显著低于对照组；GSH-Px活性在第4天时高于对照组，而第8天未见明显影响；EROD活力在染毒第8天时显著低于对照组。上述各指标在第12天时均未见改变。[结论]在染毒8d内，餐具洗洁精对小鼠肝脏抗氧化能力和解毒系统酶产生影响。     

共轭亚油酸抑制苯并(a)芘诱导小鼠前胃癌的研究

目的：探讨不同的构成的共轭亚油酸（CLA）对苯并（a)芘[B(a)P]诱导的小鼠前胃癌的抑制作用及可能机制。方法：用B(a)P在昆明种小鼠体内建立前胃癌模型,观察不同构成的CLA对小鼠前胃癌形成的抑制作用,同时采用蛋白印迹法分析小鼠前胃组织中的蛋白表达情况。结果：B(a)P组、75％纯度C9,T11-CAL组、98％纯度c9,t11-CAL组、98％纯度t10,c12-CLA组的前胃肿瘤发生率分别为100．0％、75．0％、69．2％、53．8％;蛋白印迹法分析结果表明,CAL抑制ERK－1的表达,促进MKP－1的表达,而对MEK－1的表达无明显影响,结论：不同构成的CAL对B(a)P诱导小鼠前胃癌均具有抑制作用;CAL影响MAPKs级联反应ERKs及此途径负调控子MKP－1蛋白的表达可能是其抑制肿瘤作用的机制之一。     

B（a）P和DEHP联合染毒对HepG2细胞CYP1A1和CYP3A4酶活性的影响

[目的]研究邻苯二甲酸二乙基己基酯[di-（2-ethylhexyl）phthalate,DEHP]和苯并㈦芘[benzo（a）pyrene,B（a）P]联合染毒人肝癌细胞株（HepG2细胞）对其细胞色素P450酶系1A1（cytochrome 1A1,CYP1A1）和细胞色素P450酶系3A4（CYP3A4）酶活性的影响。[方法]分别用B（a）P64．0μmol／L和DEHP62．5、125．0、250．0、500．0、1000．0μmol／L单独染毒和两者联合染毒HepG2细胞48h和72h。溶剂对照组为二甲基亚砜（dimethyl suffoxide,DMSO〈1‰）。用CCK8法检测细胞活性;用7-乙氧基异吩嗯唑-O-去乙氧基酶和7-乙氧基香豆素O-去乙基酶（EROD和ECOD）实验评价细胞CYP1A1和CYP3A4酶活性;分别用实时荧光定量PCR法和Western blot法检测CYP1A1和CYP3A4基因的mRNA和蛋白质表达水平。[结果]与DEHP单独染毒组相比,联合染毒组细胞的存活率明显下降（P〈0．01）;EROD和ECOD活性却明显增加（P〈0．05,P〈0．01）;联合染毒组CYP1A1基因仅有mRNA表达增加,但CYP3A4基因在mRNA和蛋白质表达水平均较DEHP单独染毒组明显升高（P〈0．01）。[结论]DEHP和B（a）P联合染毒诱导了HepG2细胞CYP1A1和CYP3A4酶活性,并在mRNA和蛋白质水平对CYP1A1和CYP3A4的表达量产生一定影响。     

苯并[a]芘诱导内皮细胞细胞色素P4501A1表达的研究

目的：探讨苯并[a]芘(BaP)诱导猪主动脉内皮细胞细胞色素P4501A1(CYP1A1)表达及活性的影响。方法：离体培养猪主动脉内皮细胞，不同浓度BaP(0、0．5、1．0、5．0、10．0μmol／L)染毒24h，分别以Western-blot法和免疫组化方法检测不同浓度BaP诱导内皮细胞合成CYP1A1的影响，同时还探讨了乙氧基异吩噁唑-o-去乙氧基酶(EROD)活力的变化规律。结果：Western-blot法未能检测出对照组CYP1A1的表达，而各染毒组均检出了CYP1A1的表达；免疫组化结果显示染毒组仅在部分内皮细胞呈阳性反应；EROD活力诱导高峰的BaP浓度为0．5～1.0μmol／L。结论：BaP可诱导部分猪主动脉内皮细胞合成CYP1A1；EROD活力诱导高峰的BaP浓度为0．5～1．0μmol／L。     

共轭型亚油酸对B（a）P诱导小鼠前胃癌的抑制作用

目的 研究共轭型亚油酸(CAL)的抑癌作用,并为进一步探讨CLA的抑癌机制提供线索。方法 以B(a)P诱导建立小鼠前胃癌动物模型,观察CLA对小鼠前胃癌促长阶段的抑制效果,共分5组,即色拉油阴性对照组、CLA阴性对照组、B(a)P阳性对照组、B(a)P CLA高剂量实验组和B(a)P CLA低剂量实验组。整个实验期为23周,检测细胞增殖、Pan-ras P21蛋白表达和氧化还原酶等指标。结果 短期给予CLA对B(a)P诱导的小鼠前胃癌促长阶段具有明显的抑制作用,B(a)P阳性对照组、B(a)P CLA高剂量实验组和B(a)P CLA低剂量实验组的肿瘤发生率分别为100％、60％和69％。其抑癌机制与其对细胞增殖活力的抑制及对机体GSH-Px、GST和SOD酶活力的诱导作用有关,而并不依赖于对Pan-ras P21蛋白表达的调节途径。结论 提示共轭型亚油酸是一种很有前途的化学预防剂,其抑癌机制可能与影响机体氧化还原体系密切相关。     

阿特拉津对斑马鱼影响的研究

目的研究农药阿特拉津是否具有雌激素效应。方法选择斑马鱼为受试动物，随机分为对照组和阿特拉津暴露组。观察不同浓度的阿特拉津（0．1、0．5、1．0、5．0、10．0mg／L）对斑马鱼的生长、体内卵黄蛋白原（Vtg）含量及肝脏7-乙氧基-3-异吩口恶唑酮-脱乙基酶（EROD）酶活力的影响。结果经14d暴露后，阿特拉津浓度低于1．0mg/kg时雄性斑马鱼体重增长分别为对照组的1．57、1．81和2．07倍；当阿特拉津浓度高于1．0mg／kg时，实验组斑马鱼体重出现负增长现象。当阿特拉津浓度为1．0、5．0和10．0mg／kg时，实验组雌性斑马鱼体重分别为对照组的-0．42、-2．18和-1．32倍。阿特拉津可诱导雄性斑马鱼体内Vtg表达，具有雌激素效应并抑制肝脏中EROD酶活力，与对照组相比，差异均有统计学意义（P〈0．01）。结论阿特拉津对水生动物有明确的生长和生殖毒性。     

维生素E琥珀酸酯诱导人胃癌细胞分化的作用

目的研究维生素E琥珀酸酯(VES)对胃癌细胞的诱导分化作用。方法5，10μg／ml维生素E琥珀酸酯处理人胃癌SGE-7901细胞，分别采用噻唑蓝(MTT)法检测细胞的生长；^3H-TdR掺入法测定DNA合成速率；流式细胞术检测细胞周期的分布；分光光度法检测分化标志酶的活性。结果VES可使细胞形态学改变；抑制SGC-7901细胞的生长。降低DNA的合成速率；使细胞出现G0／G1期停滞；分化标志酶碱性磷酸酶(ALP)、乳酸脱氢酶(LDH)活性降低。结论VES可诱导SGC-7901细胞分化并抑制其恶性生长。     

多氯联苯和苯并（a）芘联合作用对HepG2细胞CYPA1和微核的影响

目的探讨多氯联苯（PCBs）153通过诱导P450酶活力对苯并（a）芘【B（a）P】遗传毒性的影响。方法PCB153设3个剂量组（1、10、100μmol／L），B（a）P设1个剂量组（50μmol／L），DMSO为溶剂对照组，3-甲基胆蒽（3-MC）为阳性对照组。以不同浓度的PCB153（1、10、100μmol／L）染毒HepG2细胞48h后再与B（a）P联合染毒24h。通过荧光分光光度法测定HepG2细胞CYP1A1酶活力（EROD）。同时采用胞质分裂阻滞法微核试验（CBMNT）分析细胞的微核，计算微核率和核分裂指数（NDI）。结果与溶剂对照组相比，1、10、100μmol／L的PCB153和50μmol／L的B（a）V单独染毒均可诱导EROD活力增加，差异有统计学意义（P〈0．05）。与溶剂对照组比较，100μmol／L的PCBl53和50μmol／L的B（a）V可诱导微核率显著升高，差异有统计学意义（P〈0．01）。与B（a）V单独染毒组比较，B（a）V和PCB153联合染毒时，EROD活力和微核率均显著升高，差异有统计学意义（P〈0．05或P〈0．01）。与溶剂对照组比较，100μmol／L的PCB153和50μmol／L的B（a）V及所有联合染毒组均使HepG2细胞NDI明显降低，差异有统计学意义（P〈0．05或P〈0．01）。结论PCB153对B（a）P的遗传毒性作用具有一定的促进作用，这种促进可能与PCB153诱导P450酶活力有关。     

B(a)P对鲫鱼全脑NO、NOS水平的影响

目的　探讨苯并 (a)芘 [B(a)P]对鲫鱼全脑一氧化氮 (NO)和一氧化氮合酶 (NOS)的影响及水生态毒理学机制 ,同时为苯并 (a)芘的水污染监测探寻灵敏简便的亚致死指标。方法　设立空白对照、溶剂对照、3× 1 0 -4～ 3×1 0 -1 mg/LB(a)P处理组共 6个实验组 ,分别于染毒后 1 ,3,6和 1 2d取鲫鱼全脑进行检测。 结果　全脑一氧化氮(NO)、一氧化氮合酶 (NOS)水平与苯并 (a)芘存在着剂量及染毒时间依赖关系。结论　引起体内NOS活性升高及NO的过量产生是苯并 (a)芘在鲫鱼体内发挥毒性的机制之一。     

温石棉对A549细胞细胞色素P4501A1和谷胱甘肽S转移酶活性的影响

目的：探讨温石棉对体外培养细胞中外源性化合物代谢酶活性的影响。方法：采用不同剂量的UICC温石棉（UC）和国产茫崖温石棉（MC）分别作用于A549细胞,测A549细胞中细胞色素P4501A1（CYPA1）和谷胱甘肽S转移酶（GST）活性,并用苯并（a)芘对酶活性进行诱导,再测定温石棉对2种酶诱导活性的影响。结果：UC与A549细胞作用24h,乙氧基异酚恶唑－O－去乙基酶（EROD）活性随剂量增加呈缓慢递趋势,200mg/L UC可使EROD活性升高40％,但200mg/L UC作用48h则使其活性下降32％,提示UC对A549细胞EROD活性的影响呈现低剂量短时间诱导,而高剂量长时间抑制的趋势,MC对EROD活性的影响呈现多向性,无论作用24h还是48h,25mg/L UC作用48h则使其活性下降32％,提示UC对A549细胞EROD活性的影响呈现低剂量短时间诱导,而高剂量长时间抑制的趋势,MC对EROD活性的影响呈现多向性,无论作用24h还是48h,25mg/L的MC诱导作用最强（分别为对照组的1．86和1．28倍）,但随MC剂量增大和作用时间延长,EROD活性也随之下降,最低仅为对照组的35％,UC作用对GST的影响不明显,最高仅使GST活性升高20％,MC在25mg/L时驿GST的诱导最强,为对照组的1．4倍,但随着剂量的增加,对GST活性的上诱导转为抑制,200mg/L时GST活性下降了18．7％,先用温石棉与A549细胞作用24h,再加入苯并(a)芘对酶活性进行诱导,发现无论是UC还是MC,均未对苯并(a)芘诱导的EROD活性产生明显影响。但200mg/L的UC和100mg/L的MC均可增加GST的诱导活性。结论：不同剂量温石析对EROD和GST活性表现出不同的效应,其原因可能与2种温石棉的物理化学特性及表面活性有关。     

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 occurrence of antimicrobial substances in toilet,sink and shower drainpipes of clinical units: A neglected source of antibiotic residues

Antibiotics represent one of the most important drug groups used in the management of bacterial infections in humans and animals. Due to the increasing problem of antibiotic resistance, assurance of the antibacterial effectiveness of these substances has moved into the focus of public health. The reduction in antibiotic residues in wastewater and the environment may play a decisive role in the development of increasing rates of antibiotic resistance. The present study examines the wastewater of 31 patient rooms of various German clinics for possible residues of antibiotics, as well as the wastewater of five private households as a reference.To the best of our knowledge, this study shows for the first time that in hospitals with high antibiotic consumption rates, residues of these drugs can be regularly detected in toilets, sink siphons and shower drains at concentrations ranging from 0.02?μg·L^?1 to a maximum of 79?mg·L^?1. After complete flushing of the wastewater siphons, antibiotics are no longer detectable, but after temporal stagnation, the concentration of the active substances in the water phases of respective siphons increases again, suggesting that antibiotics persist through the washing process in biofilms. This study demonstrates that clinical wastewater systems offer further possibilities for the optimization of antibiotic resistance surveillance.     

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.     

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.     

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.     

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.