尿液分离大肠埃希菌Ⅰ类整合子分子特征及其与耐药性的关系

目的 了解尿液分离大肠埃希菌中Ⅰ类整合子及相关基因盒的分布,分析整合子与细菌耐药性的关系.方法 选取108株临床非重复分离自尿液标本中的大肠埃希菌,经全自动细菌分析系统鉴定并检测其对临床常用抗菌药物的耐药性,聚合酶链反应(PCR)检测Ⅰ类整合酶基因,对Ⅰ类整合酶阳性菌株用PCR扩增并测序分析可变区基因盒种类及可变区启动子类型.结果 108株临床非重复分离自尿液大肠埃希菌中有60株占56.0％检测到Ⅰ类整合酶基因;共检测出5种不同长度的可变区片段:8株750 bp片段不含基因盒,2株1500 bp片段为aadA2,34株2200 bp片段为dfrA 17-aadA5,4株2500 bp片段为dfrA 12-orfF-aa dA2,2株2800 bp片段为aacA4-cmlA1,其中1株大肠埃希菌同时扩增出2200、2500 bp的可变区片段,有11株Ⅰ类整合酶基因阳性大肠埃希菌未扩增出可变区;可变区启动子大多为相对较弱的启动子PcH1、PcW;Ⅰ类整合子阳性菌株对多种抗菌药物的耐药率高于Ⅰ类整合子阴性菌株.结论 Ⅰ类整合子及相关基因盒在尿液分离大肠埃希菌中分布广泛,与细菌耐药性关系密切,所携带的整合子具有较强的捕获外源性耐药基因盒的能力.     

尿液分离大肠埃希菌Ⅰ类整合子分子特征与耐药性的关系研究

目的了解社区感染尿液分离大肠埃希菌中Ⅰ类整合子的分布,并分析其与细菌耐药性的关系。方法选取114株临床非重复分离自医院门诊患者尿液标本中的大肠埃希菌,经全自动细菌分析系统鉴定并检测其对临床常用抗菌药物的耐药性,聚合酶链反应(PCR)检测Ⅰ类整合酶基因,对Ⅰ类整合酶阳性菌株用PCR扩增并测序分析可变区基因盒种类。结果 114株临床非重复分离自尿液大肠埃希菌中有50株检测到Ⅰ类整合酶基因;共检测出两种不同长度的可变区片段:1 700bp片段(30株)为dfrA17-aadA5,2 100bp片段(5株)为dfrA12-orfF-aadA2,有两株大肠埃希菌同时扩增出1 700bp和2 100bp的可变区片段,有17株Ⅰ类整合酶基因阳性大肠埃希菌未扩增出可变区;114株大肠埃希菌对氨苄西林、磺胺甲噁唑/甲氧苄啶和左氧氟沙星的耐药率较高,>50.0%,对头孢替坦、亚胺培南、厄他培南、哌拉西林/他唑巴坦、呋喃妥因、阿米卡星耐药率较低,<5.0%;Ⅰ类整合子阳性菌株对氨苄西林、庆大霉素、妥布霉素和磺胺甲噁唑/甲氧苄啶的耐药率高于Ⅰ类整合子阴性菌株。结论与医院感染相比,社区感染尿液中分离的大肠埃希菌受抗菌药物的选择压力相对较小,其对常用抗菌药物的耐药率、Ⅰ类整合子携带率均较低,同时Ⅰ类整合子中携带的基因盒种类也较单一。     

致病菌耐药因子分布及特征分析

目的 对临床菌株中的整合子分布及其携带耐药基因盒的结构特征进行分析。方法 应用多重PCR方法检测55株临床菌株中的3类整合酶基因intⅠ。并对intⅠ阳性菌株耐药基因盒进行测序及序列分析。结果 55株临床菌株均为第1类整合酶基因阳性（100％）。耐药基因盒特异PCR扩增发现，27株革兰阳性菌株和22株革兰阴性菌株均得到1913bp的扩增产物，携带基因盒为dhfr、orfF和aadA2；6株革兰阴性菌得到1664bp的产物．携带基因盒为aadA5和dfrl7。aadA2和aadA5均为编码对氨基糖苷类抗生素产生耐药的基因盒。dhfr和dfr17均为编码对磺胺类药物甲氧苄氨嘧啶产生耐药的基因盒；orfF为未知功能的开放阅读框。结论 临床致病革兰阳性菌和革兰阴性菌株均广泛存在着整合子结构．应加强对耐药基因在细菌种属间水平转移的监测工作。     

多重耐药铜绿假单胞菌Ⅰ类整合子基因盒的检测与耐药机制研究

目的对某校附属医院临床分离的多重耐药铜绿假单胞菌进行Ⅰ类整合子基因盒检测,分析其与细菌耐药性的关系。方法应用PCR方法对临床分离的50株多重耐药铜绿假单胞菌进行Ⅰ类整合子检测,并对整合子阳性株进行耐药基因盒的扩增与测序。结果 50株多重耐药铜绿假单胞菌中21株检出I类整合子(42.0%),对整合子阳性菌株可变区进行扩增得到5种不同大小的基因片段,片段大小在730~2 550 bp,片段包含编码氨基糖苷类抗生素腺苷酰基转移酶的aadB、aadA6、aadA2基因盒,编码氨基糖苷类抗生素乙酰基转移酶的aac-6Ⅱ基因盒,编码PSE-1蛋白PSE-1基因,编码二氢叶酸还原酶的dfrA1基因。结论多重耐药铜绿假单胞菌中检测出I类整合子,整合子可变区携带多种耐药基因盒,耐药基因盒与其耐药表型有相关性。     

食品中沙门菌整合子与耐药性关系研究

目的：研究食品中沙门菌的整合子携带情况及整合子与耐药性之间的关系。方法：PCR检测细菌总DNA中1、2、3类整合酶基因，确定细菌携带整合子的情况。整合子阳性菌档进一步检测整合子的可变区，分析插入基因盒的序列。结果：69株大肠菌中25株携带1类整合子，集中分布在对4种以上抗生素耐药的菌株中。插入基因盒主要是dfr(甲氧苄氨嘧啶)和aadA(氨基糖甙类)基因盒，各种基因盒组合中最常见的是difrl—aadA1。结论：细菌的多重耐药性与整合子携带高度一致，但是单个菌株的耐药谱与整合子的耐药基因盒缺乏对应关系。     

食品中大肠埃希菌整合子与耐药性的关系研究

目的：研究食品中大肠埃希菌的整合子携带情况及其与耐药性之间的关系。方法：PCR检测细菌总DNA中1、2、3类整合酶基因，确定细菌携带整合子的情况。阳性菌株进一步检测整合子的可变区，分析插入基因盒的序列。结果：50株大肠杆菌中19株携带1类整合子，2株携带2类整合子，集中分布在对4种以上抗生素耐药的菌株中。插入基因盒主要是dfr和aadA类基因盒，各种基因盒组合中最常见的是dfr17-aadA5。结论：细菌的多重耐药性与整合子携带高度一致，但是单个菌株的耐药谱与整合子的耐药基因盒缺乏对应关系。     

食品中沙门菌整合子与耐药性关系

目的 研究食品中沙门菌的整合子携带情况及整合子与耐药性之间的关系。方法PCR检测细菌总DNA中1，2，3类整合酶基因，确定细菌携带整合子的情况。整合子阳性菌株进一步检测整合子的可变区，分析插入基因盒的序列。结果69株沙门菌中25株携带1类整合子。集中分布在对4种以上抗生索耐药的菌株中。插入基因盒主要是dfr（甲氧氨嘧啶）和aadA（氨基糖甙类）基因盒，各种基因盒组合中最常见的是dfrl-aadA1。结论细菌的多重耐药性与整合子携带高度一致。     

鸡来源产超广谱β-内酰胺酶大肠埃希菌携带整合子基因的研究

目的 分析鸡肠道内共生的产超广谱β-内酰胺酶(ESBLs)大肠埃希菌整合子携带状况以及其与多重耐药性的关系.方法 从甘肃、湖北、北京、四川地区养殖场鸡粪便标本中分离的大肠埃希菌,肉汤稀释法检测菌株的耐药性,WHONET软件进行耐药性分析;筛选出的ESBLs菌株进行整合子的PCR检测和基因测序. 结果 通过药敏试验从鸡粪中分离的224株大肠埃希菌中共检出产ESBLs的菌株54株,分离率为24.1%.产ESBLs的菌株中I类整合子的携带率为63.0%,I类整合子可变区发现的耐药基因有addA1、aadA2、aadA5、aadA22,dfrA12、dfrA17、dfrI,aar-3,分别介导氨基糖苷类、磺胺类抗生素以及利福平的耐药性.aadA22是在国内菌株中首次报道.Ⅱ类整合子携带率为5.6%,携带的耐药基因包括sat、ereA、aadA1.Ⅲ类整合子酶阳性的有3株菌,但其可变区未检出任何耐药基因. 结论 I类整合子主要介导氨基精苷类抗生素和甲氧嘧啶的耐药性,在大肠埃希菌ESBLs菌株的多重耐药性中具有重要的作用,加强养殖动物大肠埃希菌耐药性以及整合子携带状况的监测,对防止耐药菌株的广泛传播,改善临床抗生素的疗效具有重要意义.     

临床分离阴沟肠杆菌耐药性与I类整合子关系研究

目的了解临床分离阴沟肠杆菌整合子的分布情况,探讨I类整合子与其耐药性关系。方法收集2014年9月-2015年6月本院临床分离的阴沟肠杆菌,用Vitek2-compact全自动微生物分析仪进行细菌鉴定和大部分药敏试验,少部分采用K-B法,PCR法检测I类整合酶、基因盒。用Hinf I对基因盒的PCR产物进行酶切,相同酶切图谱随机挑取1例进行测序。结果Ⅰ类整合子检出率为54.7%(64/117)。整合子阳性菌对头孢曲松、头孢他啶、庆大霉素、阿米卡星、妥布霉素、环丙沙星、左旋氧氟沙星、复方新诺明的耐药率明显高于阴性菌,差异均有统计学意义(P0.05)。基因盒种类以及菌株数分别为dfrA17-aadA5(26株)、aacA4-cat B8-aadA1(10株)、dfrA15-aadA2(7株)、dfrA12-orf FaadA2(6株)、aad B-aadA2(5株)、dfrA1-aadA5(4株)、cat B8-aadA1(2株)、dfrA15(2株)。结论 I类整合子在介导阴沟肠杆菌多重耐药性方面有重要作用。     

耐碳青霉烯酶类肺炎克雷伯菌中整合子及相关基因盒的分布

目的 了解耐碳青霉烯类肺炎克雷伯菌整合子及相关基因盒的分布,分析整合子与耐碳青霉烯类肺炎克雷伯菌多药耐药的关系.方法 采用革兰阴性杆菌药敏卡检测耐碳青霉烯类肺炎克雷伯菌对抗菌药物的敏感性,聚合酶链反应(PCR)法检测Ⅰ、Ⅱ、Ⅲ类整合酶基因(intⅠ1、intⅡ2、intⅢ3)及Ⅰ类整合子可变医基因盒,并分析可变区上游启动子的类型.结果 74株耐碳青霉烯类肺炎克雷伯菌中有67株检测到Ⅰ类整合酶基因,检出率为90.5％,2株检测到Ⅱ类整合酶基因,检出率为2.7％,未检测到Ⅲ类整合酶基因阳性菌株;55株(74.3％)成功扩增出Ⅰ类整合子可变区,主要携带甲氧苄啶及早期使用的氨基糖苷类抗菌药物耐药基因,可变区启动子大多为弱启动子;携带Ⅰ类整合子菌株对常用抗菌药物的耐药率与Ⅰ类整合子阴性菌株之间的差异无统计学意义.结论 Ⅰ类整合子及相关基因盒在耐碳青霉烯类肺炎克雷伯菌中分布广泛.所携带的整合子具有非常强的从周围环境中捕获耐药性基因盒的能力.     

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.