避孕套的体外细胞毒性检测实验

目的:通过两种避孕套的体外细胞毒性实验,探讨适合避孕套的细胞毒性检测方法。方法:按照GB/T16886.5的体外细胞毒性评价方法要求,用琼脂覆盖法和MTT比色法检测两种避孕套的细胞毒性。结果:用琼脂覆盖法检测出两种避孕套的细胞毒性均为2级;用MTT比色法检测时,在浸提液浓度为50%时,相对增值率(RGR)避孕套A为5%,避孕套B为7%,两者差异无统计学意义(P>0.05);在浸提液浓度为10%时,避孕套A的RGR为87%,避孕套B为99%,两者差异无统计学意义(P>0.05);在浸提液浓度为20%时,避孕套A的RGR为42%,避孕套B为77%,两者有统计学差异(P<0.05)。结论:由于MTT比色法具有定量评价的优点,更适合避孕套的细胞毒性检测。     

天然胶乳橡胶避孕套的体外细胞毒性试验研究

目的研究天橡避的体外细胞毒性,调查国内市售避孕套的细胞毒性现状。方法遵照GB/T16886.5和GB/T14233.2-2005(第2部分:生物学试验方法)体外细胞毒性的实验原则,采用琼脂覆盖法、显微镜观察法、噻唑蓝(MTT)比色法,在小鼠成纤维细胞(L929株)上对受试避。结果用琼脂覆盖法检测,6批不同品牌避孕套均具有2级细胞毒性反应。用显微镜观察法检测,6批不同品牌避孕套(按6 cm2/ml比例浸提)在浸提液浓度为100%、50%、20%和10%时,分别具有4级、4级、2级、1或0级细胞毒性反应。用MTT比色法检测,来自6个品牌的15批避孕套(按6 cm2/ml比例浸提),在浸提液浓度为50%、20%、10%时,分别具有4级(RGR≤15%)、2级(RGR:50%～70%)、1级(RGR≥80%)细胞毒性反应。结论试验表明受试天然胶乳橡胶避孕套均有不同程度的细胞毒性反应。MTT比色法具有定量评价的优点,易于操作,与琼脂覆盖法和显微镜观察法相比更适合避的细试验。     

壳聚糖抗菌喷膜体外细胞毒性检测的探讨

壳聚糖是近十年来生物医药领域中发展迅速的一种天然生物材料,其生物安全性也备受关注。本研究采用浸提法中的MTT比色法和间接接触中的琼脂扩散法检测壳聚糖抗菌喷膜的体外细胞毒性。MTT比色法检测时,不同浸提比例的受试物,细胞毒性差异明显。琼脂扩散法检测时,不同琼脂浓度,结果也有差异。鉴于不同检测方法之间结果的差异,因此,在检测中,要根据不同的产品类型选择适宜的方法。     

口岸医疗器械产品体外细胞毒性结果分析

目的了解2012年-2014年出入境检测机构送检医疗器械细胞毒性的分布状况。方法参考医疗器械生物学评价ISO标准,采用L929细胞系对样品浸提液进行直接或间接细胞毒性评价,直接法细胞暴露于不同浓度浸提液,采用MTT测量细胞活力作为终点。间接法在细胞上添加琼脂,浸提液湿润的滤纸置于琼脂上,镜检细胞的毒性反应。结果送检的184份医疗器械样品,合格样品数为150份,总合格率为81.5%,不同管理分类和目录分类的医疗器械合格率不一,检出细胞毒性大小存在较大差异。结论生产企业和检测机构应重点关注细胞毒性大的医疗器械,尤其是Ⅲ类管理类别产品,在生产和出口检测环节给予严格把关。     

不同浸提介质对医用护理垫体外细胞毒性评价的影响简

目的：研究不同浸提介质对医用护理垫体外细胞毒性评价的影响。方法：根据ISO 10993-5：2009的试验原则和评价标准,采用不同的浸提介质制备医用护理垫浸提液,小鼠成纤维细胞L929与浸提液共培养24h,MTT 法评价浸提液对细胞生长的影响,并计算细胞存活率（Viab.%）。结果：医用护理垫不同浸提液的细胞毒性结果有统计学差异,含血清浸提介质使细胞生长抑制,Viab.%值为68.6%,而其余三种浸提介质细胞生长状态良好, Viab.%均＞80%。结论：不同的浸提介质对医用护理垫细胞毒性结果有直接影响,因此在评价医用材料的细胞毒性时,必须明确所使用的浸提介质。     

一次性使用无菌注射器及注射器用活塞体外细胞毒性研究

目的：探讨目前市场上一次性使用注射器及注射器用活塞的细胞毒性是否符合GB15810-2001《一次性使用无菌注射器》、YY/T0243-2016《一次性使用注射器用活塞》的要求。方法：使用含10%胎牛血清的DMEM培养基(DMEM)作为浸提介质,供试品分为两组,一组取注射器采用公称容量法浸提;另一组取注射器活塞,按重量法浸提,浸提液分别与L929细胞接触培养,采用四唑盐比色法(MTT法)进行吸光度检测,计算细胞的相对增殖率。结果：部分注射器用活塞细胞毒性较大。结论：需要加强对一次性使用无菌注射器的细胞毒性评价。     

浸提方法对药用卤化丁基橡胶塞体外细胞毒性评价的影响

目的:研究不同浸提方法对药用卤化丁基橡胶塞体外细胞毒性评价的影响。方法:采用不同的浸提方法制备了浸提液,以MTT法评价药用卤化丁基橡胶塞浸提液对小鼠成纤维细胞L929活性与增殖的影响。结果:通过不同的浸提方法制备的浸提液,11批中的9批样品体外细胞毒性实验出现了有统计学意义的差异。结论:破坏原有样品的正常形态即改变表面积与体积比对于评价卤化丁基橡胶塞的体外细胞毒性实验(MTT)是有影响的。     

膀胱肿瘤细胞mRNA致敏的树突状细胞体外抗肿瘤免疫反应

目的:研究小鼠膀胱癌BTT739细胞mRNA致敏的树突状细胞(DC)诱导特异性的抗肿瘤免疫反应。方法:使用rmGM-CSF和rmIL-4培养诱导小鼠骨髓细胞分化为DC,从BTT739细胞中提取mRNA致敏DC,与小鼠淋巴细胞混合培养以诱导特异性的细胞毒性T淋巴细胞(CTL)。采用MTT比色法和软琼脂法检测CTL对BTT739细胞的杀伤作用。结果:MTT比色法和软琼脂法检测结果显示:在靶细胞∶效应细胞不同浓度组中,BTT739实验组和对照组的OD值和肿瘤集落形成个数都有显著性差异(P<0 01,P<0 05),在靶细胞∶效应细胞的比例为1∶5、1∶25、1∶50和1∶100时,其杀伤率分别为25. 0%、36 .1%、45 .9% 和58 .2%;当效应细胞作用于AGS细胞时,其OD值无显著差异。结论:以膀胱肿瘤细胞mRNA致敏DC诱导CTL可有效杀伤膀胱肿瘤细胞。     

不同浸提介质对一次性使用血液灌流器体外细胞毒性评价的影响

目的:探讨不同浸提介质对一次性使用血液灌流器细胞毒性的影响.方法:采用能快速准确地评价细胞存活率和细胞毒性的定量分析方法-M T T法,分别检测不同血液灌流器在含血清培养基、非含血清培养基和0.9%氯化钠注射液三种浸提介质的浸提液对小鼠成纤维细胞相对存活率的影响.结果:检测结果表明,不同的浸提介质,细胞毒性结果差异明显.氯化钠注射液浸提的样品存活率最高,非含血清培养基次之,含血清培养基浸提的样品存活率最低.结论:在检测中,要根据产品的使用方法和用途选择适宜的浸提介质,尽量模拟临床使用进行选择.     

起搏器用植入材料的细胞毒性研究

目的:对NERC植入式人工心脏起搏器拟用的环氧树脂、钛金属以及硅橡胶等材料进行细胞毒性实验,探讨各材料对L-929细胞的毒性作用情况,为材料在起搏器的应用提供依据。方法:按照GB/T 16886,制备样品及各种材料的浸提液。分别在48h、72h、96h天,对细胞生长状况进行观察,并通过MTT方法,检测各种材料浸提液对成纤维细胞的细胞毒性作用,根据细胞相对增值率,对材料毒性进行分级。结果:成纤维细胞在起搏器相关材料浸提液中生长正常,细胞形态良好,各浓度浸提液对成纤维细胞的相对增殖率均在90%以上,材料毒性分级为0级或一级。结论:选用相关材料细胞相容性良好,基本上无细胞毒性,符合植入式人工心脏起搏器材料细胞毒性要求。     

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.