副溶血性弧菌食源性疾病分离株的RAPD分子分型研究

目的：探讨副溶血性弧菌食源性疾病分离株的基因多态性。方法：采用随机扩增多态性分析(RAPD)对副溶血性弧菌食源性疾病分离株进行分子分型，结合SPSS软件构建以上菌株的带型关系系统树状图，对菌株进行基因多态性分析。结果：所采用引物能从副溶血性弧菌扩增出特异性的DNA条带，分型效果较好，所有46株副溶血性弧菌中大部分的RAPD结果经聚类分析可分为3个主要聚类群，较好地反应了不同血清型和不同来源菌株的亲缘关系。结论：可应用RAPD方法进行食源性疾病的流行病学调查和溯源。     

沙门菌REP-PCR分子分型技术的优化及其在耐药菌株中的应用

目的优化沙门菌REP-PCR分子分型技术,并在沙门菌耐药菌株分型研究中应用,为构建沙门菌同源性追踪体系提供数据。方法以肠炎沙门菌510041基因组DNA为模板,根据参考文献确定REP引物,PCR扩增其基因组中靶序列。对反应体系模板量、Mg2+浓度和引物浓度的优化,采用对优化项目设置梯度,其它条件不变的方法进行。以优化的REP-PCR法分析24株沙门菌流行耐药株REP-PCR指纹图谱。根据指纹图谱条带对菌株进行分型,并将分型结果与菌株耐药谱分型结果作比较。结果PCR反应体系DNA模板量100ng/25μl,Mg2+浓度2.0mmol/L,上下游引物浓度各0.4μmol/L时,指纹图谱条带最清晰、明亮;不同血清群和血清型沙门菌株间REP-PCR指纹图谱差异较大,可在0.5kb到2.5kb范围内出现2至6条条带;24株沙门菌流行耐药株用该法可分为15型,根据耐药谱可分为7型。结论建立了优化的沙门菌REP-PCR分子分型技术;REP-PCR指纹图谱分型比耐药谱分型更加敏感。     

阴沟肠杆菌随机扩增多态性DNA法基因分型

目的建立阴沟肠杆菌(ECL)随机扩增多态性DNA(RAPD)法基因分型图谱.方法以优化的随机引物和反应体系对临床分离的159株ECL进行RAPD法基因分型,并按DNA条带数及片段大小绘制指纹图谱.结果 159株临床分离ECL共得121种RAPD指纹图谱.结论 RAPD技术可将临床分离ECL分型121种.     

大连市伤寒沙门菌扩增片段长度多态性分型

目的 运用扩增片段长度多态性(AFLP)技术分析辽宁省大连市2000~2006年伤寒沙门菌分离株的多态性及遗传关系。方法 采用PstI/Mse I型内切酶,选择9种引物组合对30株不同来源的菌株进行AFLP分子分型。结果 30株不同来源的伤寒沙门菌分为29个AFLP基因型,呈现丰富的多态性。结论 AFLP技术是一种兼具有效性和效率性,适用于伤寒沙门菌分子流行病学研究。     

沙门菌基因间共有重复序列-PCR分子分型方法的优化及应用初探

目的优化沙门菌基因间共有重复序列-PCR(ERIC-PCR)分子分型方法,分析沙门菌标准菌株及流行分离株基因组DNA ERIC-PCR指纹图谱。方法提取鼠伤寒沙门菌基因组DNA作为模板,根据ERIC核心片段设计引物,运用ERIC-PCR技术扩增沙门菌基因组中的靶序列,PCR产物经琼脂糖凝胶电泳后用凝胶成像分析仪对图谱进行观察分析。反应体系中模板量、Mg2+浓度、引物浓度和退火温度的优化实验则采用对优化项目设置梯度、其它条件不变的方法进行。以优化好的ERIC-PCR方法对16株沙门菌及1株大肠杆菌进行分析。结果在总体积为25μl的反应体系中,选择DNA模板量为100ng/25μl,Mg2+浓度为2.0mmol/L,引物ERIC1R、ERIC2浓度分别为0.4μmol/L,退火温度为52℃时,扩增产物的电泳图谱条带最清晰完整。不同血清群、型和来源的沙门菌株间基因组DNA ERIC-PCR指纹图谱带型差异较大,可在250～5000bp范围内出现3～13条条带,并在250bp处出现一条特征条带。结论优化了沙门菌ERIC-PCR的重要反应条件。ERIC-PCR法能区分不同来源的沙门菌,可用于沙门菌病的流行病学调查和同源性追踪,弥补传统分型方法的不足。     

白色假丝酵母菌的随机扩增多态性DNA分型研究

目的建立医院感染白色假丝酵母菌的基因多态性DNA分型方法,了解白色假丝酵母菌医院感染的分子流行病学情况,并探讨其基因多态性与真菌药物敏感性检测结果的可能关系。方法收集临床各病区送检的住院患者白色假丝酵母菌感染标本30份和其相应患者资料、抗真菌药物敏感性检测结果,采用经优化的随机扩增多态性(RAPD)DNA方法,对30株白假丝酵母菌进行基因多态性分型,利用Phylip3.67聚类分析软件分别用邻接法和算术平均数的非加权成组配对法,对RAPD扩增条带结果进行聚类分析。结果随机引物OPE-03进行RAPD扩增的指纹图谱清晰,带型稳定,多态性丰富,可以作为分型引物;30株不同来源的菌株可大致分为3种亲缘关系;两种聚类分析结果相同,提示该实验结果可靠。结论白色假丝酵母菌基因多态性分布可能与菌株的来源有关;RAPD多态性可能与其耐药性有关;不同聚类分析方法的RAPD图谱分析结果相同。     

弗氏柠檬酸杆菌随机扩增多态性DNA法基因分型

目的建立弗氏柠檬酸杆菌(Citrobacter freundii)随机扩增多态性DNA(RAPD)法基因分型图谱. 方法以优化的反应体系及单一随机引物L8,对临床分离的116株C.freundii进行RAPD分析,并按指纹图上DNA条带数及片段大小绘制基因分型图谱. 结果 116株临床分离C.freundii共得78种RAPD型. 结论 RAPD法可将C.freundii分型78种.     

一起由肠炎沙门菌所致食物中毒的病原分析

目的对2016年龙岩市一起食物中毒事件中分离的肠炎沙门菌进行分子分型及耐药性分析,以明确病因。方法采集患者粪便标本和YH超市卤水、卤制鹌鹑蛋进行常规病原学分离培养,对可疑菌株用VITEK 2Compact进行系统生化鉴定及血清分型。对分离的肠炎沙门菌菌株进行PFGE分型和药敏试验。结果从病人粪便中分离到31株、从卤制鹌鹑蛋中分离到1株共计32株肠炎沙门菌。对其中24株进行分析。PFGE图谱显示24株菌中有23株条带完全一致,1株与其他23株条带存在差异,两者相似度为91.7%。24株菌株耐药性存在一定差异。结论综合流行病学调查、临床症状和病原学检测及分子分型,证实本起食物中毒事件系由同一来源的肠炎沙门菌引起。     

肠炎沙门菌可变数目串联重复序列位点用于多位点可变数目串联重复序列分型分析的评价

目的 评价不同肠炎沙门菌可变数目串联重复序列(VNTR)位点用于多位点可变数目串联重复序列(MLVA)分型的可行性.方法 选取已报道使用的肠炎沙门菌11个VNTR位点,对中国不同时间和地区分离的16株菌进行初步评价,选取具有单一扩增条带的位点进行104株肠炎沙门茵的MLVA分型分析.对这些菌株同时进行脉冲场凝胶电泳(PFGE)分析,比较MLVA分型方法与PFGE分型方法对菌株分型能力的强弱.结果 初筛得到7个VNTR位点用于扩大菌株的分析,这些位点将104株菌分为16个MLVA型别,D值为0.7222,这些菌株同时被分为22个PFGE型别,D值为0.7974.对两种方法各自所分的最大组包含的菌株进行比较,发现PFGE具有更强的分辨能力;从频数分布看,PFGE方法分型结果比较分散,MLVA分型较为集中.结论 用于国际肠炎沙门菌分型具有扩增多态性的VNTR位点在国内分离株中并不都具有多态性结果,在MLVA方法学建立中应选择更多的VNTR位点进行广泛的筛选才有利于国际实验室间的方法的统一.     

肠炎沙门菌可变数目串联重复序列位点用于多位点可变数目串联重复序列分型分析的评价

目的 评价不同肠炎沙门菌可变数目串联重复序列(VNTR)位点用于多位点可变数目串联重复序列(MLVA)分型的可行性.方法 选取已报道使用的肠炎沙门菌11个VNTR位点,对中国不同时间和地区分离的16株菌进行初步评价,选取具有单一扩增条带的位点进行104株肠炎沙门茵的MLVA分型分析.对这些菌株同时进行脉冲场凝胶电泳(PFGE)分析,比较MLVA分型方法与PFGE分型方法对菌株分型能力的强弱.结果 初筛得到7个VNTR位点用于扩大菌株的分析,这些位点将104株菌分为16个MLVA型别,D值为0.7222,这些菌株同时被分为22个PFGE型别,D值为0.7974.对两种方法各自所分的最大组包含的菌株进行比较,发现PFGE具有更强的分辨能力;从频数分布看,PFGE方法分型结果比较分散,MLVA分型较为集中.结论 用于国际肠炎沙门菌分型具有扩增多态性的VNTR位点在国内分离株中并不都具有多态性结果,在MLVA方法学建立中应选择更多的VNTR位点进行广泛的筛选才有利于国际实验室间的方法的统一.     

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.     

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.