高原红细胞增多症患者红细胞膜ATP酶活性及离子转运功能

目的：了解高原红细胞增多症（ＨＡＰＣ）患者红细胞膜ＡＴＰ酶活性及红细胞内离子水平,探讨离子转运变化。方法：选择２６例ＨＡＰＣ患者,采用Ｓｈａｌｅｖ方法测定红细胞膜ＡＴＰ酶活性及细胞内相关离子浓度。结果患者红细胞膜Ｎａ＾＋－Ｋ＾＋－ＡＴＰ酶、Ｃａ＾２＋－ＡＴＰ酶、Ｍｇ＾２＋－ＡＴＰ酶活性均明显低于正常人（Ｐ〈０．０１）;而红细胞内Ｎａ＾＋、Ｃａ＾２＋浓度却明显高于正常人（Ｐ〈０．０１,Ｐ〈０．０５）     

二硫化碳对神经细胞混悬液及突触膜ATP酶和胆碱脂酶活性影响

本研究目的在于寻求神经性毒物体外的测试方法，并对ＣＳ２的毒作用机制进行探讨，选用神经细胞混悬液及超速密度梯度离心分离的突触膜为模型，观察ＣＳ２不同染毒浓度对Ｎａ＋－Ｋ＾＋－ＡＴＰ酶及胆碱酯酶活性的影响。结果表明，ＣＳ２对Ｎａ＾＋－Ｋ＾＋－ＡＴＰ酶有明显的抑制作用，而对胆碱酯酶活性无影响，推测Ｎａ＾＋－Ｋ＾＋－ＡＴＰ酶在ＣＳ２的毒作用机制中起一定作用，突触膜可作为研究预测神经性毒物的毒性潜力。     

甲基汞对细胞膜损伤作用

采用生化和细胞生物学方法研究了不同剂量甲基汞对细胞膜系统损伤作用及机理。结果红细胞膜，脑肝肾微粒体膜Ｔ－ＡＴＰ酶，Ｍｇ＾＋＾＋－ＡＴＰ酶，Ｎａ＾＋，Ｋ＾＋－ＡＴＰ酶活性与对照组相比显著降低，并随剂量增加而下降。红细胞膜Ｎａ＾＋Ｋ＾＋－ＡＴＰ酶与脑肾微粒体膜Ｎａ＾＋－Ｋ＾＋－ＡＴＰ酶活性呈正相关。红细胞膜，脑微粒体膜ＳＨ基含量均显著降低（Ｐ＜０．０１）。肾ＳＨ基含量与肾三种ＡＴＰ酶均呈负相关，脑ＳＨ     

锌对大鼠成骨细胞膜Ca2+-ATP酶活性的调节

为了研究锌对大鼠成骨细胞膜Ｃａ＾２＋－ＡＴＰ酶和Ｎａ＾＋Ｋ＾＋－ＡＴＰ酶活尾及其机制,实验设计照组和３个补锌组。采用孔雀绿比色法同步测定膜Ｃａ＾２＋－ＡＴＰ酶和Ｎａ＾２＋,Ｋ＾＋－ＡＴＰ酶活性,以研究Ｚｎ＾２＋对酶活性的影响。     

热应激大白鼠心肌钙调素含理与钙代谢的研究

观察了热应激在鼠心肌钙调素及钙代谢的变化。结果表明，当热应激大鼠肛温达３９度时，心肌ＣａＭ含量升高，之后则随肛温升高而下降，呈抛物线型，至肛温４２度以上时，较对照下降３７．５％。热应激大鼠心肌和细胞内质网、线粒体Ｃａ＾＋－ＡＴＰ酶活力随肛温升高逐步下降，至肛温４２度以上时，分别下降３６．５％，３５．５％和３８．４％。心肌细胞内质网Ｃａ＾２＋主动转运速率和Ｃａ＾２＋－ＡＴＰ酶活力变化密切相关。热应激     

乌贼墨对H22癌细胞内Ca2+浓度、核膜Ca2+/Mg2+-ATP 酶活性及c-jun表达的影响

利用荧光探针和免疫组织化学方法,研究了乌贼墨对Ｈ２２癌细胞内ＣＡ＾２＋浓度,核膜Ｃａ＾２＋／Ｍｇ＾２＋－ＡＴＰ酶活性及ｃ－ｊｕｎ表达的影响。结果发现,乌贼墨使Ｈ２２癌细胞内Ｃａ＾２＋浓度分别降低了６９％和７９％,核膜Ｃａ＾２＋／Ｍｇ＾２＋－ＡＴＰ酶活性分别降低了２１％和３７％,ｃ－ｊｕｎ表达明显减少。     

氟对人体红细胞膜C3b,IC受体含量及Na^＋—K^＋ATP酶活性的影响

用花环法及酶学比色法检测了氟暴露工人红细胞膜Ｃ３ｂ体，免疫复合物受体含量及Ｎａ＾＋－Ｋ＾＋ＡＴＰ酶活性。结果表明氟暴露工人红细胞膜Ｎａ＾＋－Ｋ＾＋ＡＴＰ酶活性明显低于对照组，但Ｃ３ｂ受体及免疫复合物受体与对照组比较差异无显著性。提示氟对红细胞具有一定的毒笥作用。     

镉对体外培养肾组织中Ca^2＋—APTase对影响及尼莫地 …

目的 探讨镉对镉对组织中Ｃａ＾２＋－ＡＴＰａｓｅ的影响尼尼莫地平（Ｎｉｍｏ）对其的干预作用。方法 在体外条件下,测定ＣｄＣｌ２对肾组织Ｃａ＾２＋－ＡＴＰａｓｅ及乳酸脱氢酶（ＬＤＨ）、碱性磷酸酶（ＡＬＰ）、尿Ｎ－乙酰－Ｄ－氨基葡萄苷酶（ＮＡＧ）等多种肾损伤标志酶活力的作用及Ｎｉｍｏ干预处理后的影响。结果 在低浓度ＣｄＣｌ２组,Ｃａ＾２＋－ＡＴＰａｓｅ的活力明显升高,１００ｍｇ／Ｌ ＣｄＣｌ２组Ｃａ＾     

拟除虫菊酯类农药对大鼠肝线粒体,微粒体Ca^2＋—ATP酶活力…

采用离体实验方法，观察了拟除虫菊酯类农药溴氰菊酯、氯氰菊酯对大鼠肝线粒体、微粒体Ｃａ＾２＋－ＡＴＰ酶活力的影响。结果表明，加入溴氰菊酯、氯氰菊酯１５ｍｉｎ后，各剂量组线粒体、微粒体Ｃａ＾２＋ＡＴＰ酶均有明显的抑制作用，与对照组相比均具有显著性差异，（Ｐ＜０．０５或Ｐ＜０．０１），且存在明显的剂量－效应关系。作用３０ｍｉｎ后各剂量组线粒体、微粒体Ｃａ＾２＋－ＡＴＰ酶仍继续下降，未见有恢复的趋势。     

氯氰菊酯对大鼠肝脏磷酸化酶a,Ca^2＋—ATP酶活力的影响

采用整体和离体相结合方法，观察了氯氰菊酯对大鼠肝脏磷化酶ａ，Ｃａ＾２＋－ＡＴＰ酶活力的影响。整体实验表明，氯氰菊酯染毒后可使大鼠肝脏磷酸化酶ａ明显升高，Ｃａ＾２＋－ＡＴＰ酶含量明显下降，与对照组相比有显著性差异（Ｐ＜０．０５或Ｐ＜０．０１），且存在明显的剂量－效应关系。而离体实验表明，氯氰菊酯也可引起大鼠肝线粒体、微粒体Ｃａ＾２＋－ＡＴＰ酶显著下降，也存在明显的剂量－效应关系。     

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.     

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.     

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.     

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.