纸片扩散法常规检测淋球菌药敏试验可靠性研究

目的了解纸片扩散法（K-B法）常规检测淋球菌药敏结果可靠性。方法使用K-B法临床常规检测淋球菌分离株的药物敏感性,采用琼脂稀释法测定上述保存菌株的最低抑菌浓度（MIC）,对两者符合率和敏感性、耐药性进行比较。结果检测72株淋球菌对5种药物的敏感性和MIC,K-B法与琼脂稀释法的符合率分别为青霉素72.2%（52/72）、四环素86.1%（62/72）、环丙沙星59.7%（43/72）、头孢曲松37.5%（27/72）、壮观霉素98.6%（71/72）;两种方法检测菌株对四环素的耐药率均为91.7%,对大观霉素的敏感性差异无统计学意义（P〉0.05）,青霉素K-B法耐药率低于琼脂稀释法,差异有统计学意义（P〈0.05）;环丙沙星K-B法耐药率高于琼脂稀释法,差异有统计学意义（P〈0.01）,头孢曲松K-B法敏感率高于琼脂稀释法,差异有统计学意义（P〈0.01）。结论采用K-B法常规检测淋球菌药物敏感性：（1）大观霉素、四环素符合率高,结果可靠,头孢曲松一致率低,应慎用其结果;（2）K-B法可漏检部分青霉素耐药菌、漏检多数头孢曲松中敏菌株,影响头孢曲松耐药趋势的观察,部分环丙沙星K-B法耐药菌为假阳性;（3）头孢曲松和大观霉素耐药的菌株必须采用琼脂稀释法确证其结果。     

鼠伤寒沙门菌临床分离株对喹诺酮类药物耐药机制的研究

目的 研究引起儿童腹泻鼠伤寒沙门菌对喹诺酮类抗菌药物的耐药机制.方法 采用K-B法测定62株鼠伤寒沙门菌对常用抗菌药物的敏感性;应用PCR法和DNA测序法检测喹诺酮耐药决定区(QRDRs)和质粒介导的喹诺酮耐药基因;采用接合试验测定耐药基因的转移性;PFGE法测定耐药菌株的同源性.结果 62株肠伤寒沙门菌中有40株对环丙沙星耐药(MIC≥0.5 μg/ml),其中28株为低水平耐药,12株为高水平耐药,且所有对环丙沙星耐药菌株同时对其他多种抗菌药物耐药;40株环丙沙星耐药菌株分属于4种PFGE型,分别是A型7株、B型4株、E型1株、D型28株;两株对环丙沙星高水平耐药菌株同时存在gyrA和parC两个位点的突变,其余环丙沙星耐药菌株仅发现gyrA 1个位点的突变,未检测到qnr和qepA基因;62株鼠伤寒沙门菌中有23株为aac-(6′)-Ib-cr阳性,其中19株PFGE分型为D型.结论 腹泻患儿分离的肠伤寒沙门菌对环丙沙星耐药率高,喹诺耐耐药决定区gyrA基因的点突变和携带aac-(6′) -Ib-cr基因是导致鼠伤寒沙门菌对环丙沙星耐药的主要原因.     

200株淋球菌耐药检测结果分析

目的了解本院分离的200株淋球菌对壮观霉素、头孢曲松、头孢克肟、环丙沙星、青霉素和四环素的耐药性,分析耐药菌株的流行特点,指导临床合理用药。方法采用琼脂稀释法测定菌株对6种抗菌素的最小抑菌浓度(MIC),判断敏感性按WHO西太平洋地区淋球菌耐药性监测统一标准。用纸片酸度法监测产β-内酰胺酶淋球菌(PPNG)菌株。结果 200株淋球菌中,对6种抗菌素的耐药率以环丙沙星为首,耐药率高达94.5%;其次是青霉素,耐药率达92.0%,其中产β-内酰胺酶淋球菌(PPNG)49株(24.5%);四环素耐药率为67.5%,其中质粒介导高度耐四环素淋球菌(TRNG)56株,占28.0%;未发现头孢曲松、头孢克肟耐药菌株,但其低敏率分别为7.0%,5.5%,未发现壮观霉素耐药菌株和低敏菌株;环丙沙星、青霉素和四环素MIC50及MIC90均已超过耐药标准;二重耐药青霉素和环丙沙星同时耐药共检出139株(69.5%)最高,青霉素、四环素和环丙沙星同时耐药109株(54.5%)。结论环丙沙星、青霉素和四环素耐药率较高,提示对淋病的治疗效果差;壮观霉素、头孢曲松和头孢克肟的敏感性较高,推荐壮观霉素、头孢曲松和头孢克肟作为本地区治疗淋病的首选药物,同时定期监测淋球菌的耐药性,以指导临床合理应用抗菌素。     

内膜泵蛋白影响淋球菌对环丙沙星的耐药水平

目的　探讨淋球菌内膜泵蛋白同环丙沙星 (CIP)耐药的关系。方法　利用NaN3 阻断泵蛋白 ,分别测定未加入NaN3 时和加入NaN3 后淋球菌对环丙沙星的吸收和积累量。结果　淋球菌对CIP的吸收有一定的极限 ,敏感组和耐药组的吸收极限分别介于 70～ 110ng和 2 0～ 5 5ng之间。未加入NaN3 时 ,敏感组CIP积累量为 94 . 2ng ,明显高于耐药组的 39. 4ng(P <0. 0 1)。加入NaN3 后 ,耐药组CIP积累量由 39 4ng上升到 78ng(P <0 . 0 5 ) ,该水平与未加入NaN3 时敏感组比差异无统计学意义 (P >0 . 0 5 )。加入NaN3 后 ,敏感组CIP积累量为 95ng ,与未加入NaN3 时比较无明显改变 (P >0. 0 5 )。 6株敏感菌内膜上均没有泵蛋白 ,4株高水平耐药菌有泵蛋白 ,2株低水平耐药菌没有泵蛋白。结论　淋球菌内膜泵蛋白主动泵出CIP ,导致菌体内CIP积累量不足 ,这是引起淋球菌对CIP高水平耐药的重要因素 ;NaN3 可以阻断泵蛋白泵出CIP。     

80株大肠埃希菌靶位基因突变对喹诺酮耐药影响

目的　探讨大肠埃希菌靶位基因突变对喹诺酮类药物耐药的影响。方法　本研究分别用琼脂稀释法和K -B纸片扩散法药敏试验检测了 80株致泌尿系感染的大肠埃希菌环丙沙星MIC的分布和对四种喹诺酮类药物的敏感性 ;PCR扩增大肠埃希菌的gyrA和 parC基因的QRDR区 ,分别对其进行限制性内切酶酶切分析和SSCP分析 ,以检测药物靶位基因可能存在的突变。结果　 80株致泌尿系感染的大肠埃希菌中有 4 7株对环丙沙星耐药 ,耐药率达 5 8.75 % ,2 0株对环丙沙星敏感的菌株 gyrA基因QRDR区未发生改变 ,而 13株敏感株和 4 7株耐药株gyrA 2 4 7bp位点处均存在突变 ,且这 13株对环丙沙星敏感的菌株均对萘啶酸耐药。 33株对环丙沙星敏感的菌株parCSSCP分析 ,均未存在突变。 结论　① 80株致泌尿系感染的大肠埃希菌对环丙沙星的敏感性和对萘啶酸的敏感性存在明显差异 ;②gyrA基因是大肠埃希菌喹诺酮类药物的主要作用靶位。在某些菌株中 ,其 2 4 7位核苷酸位点的改变仅使细菌对环丙沙星的敏感性下降 ,parCQRDR区的突变使细菌的耐药程度增加。     

淋病奈瑟氏菌对环丙沙星耐药性与喹诺酮类耐药决定区突变的关系

目的了解上海地区淋球菌流行株对喹诺酮类抗生素的敏感性,探讨淋球菌耐药株gyrA与parC基因突变与淋球菌耐氟喹诺酮类药物之间的关系.方法采用琼脂扩散法对淋球菌临床分离株对行喹诺酮类抗生素敏感性测定,同时运用PCR技术扩增gyrA基因和parC基因的喹诺酮类耐药决定区,并对典型株的PCR产物直接进行测序分析.结果所分离的80株菌株对环丙沙星MIC为敏感、中介、耐药分别为1株、3株和76株;产物测序结果显示淋球菌敏感株只检出了gyrA基因在Asp95处的单位点突变;中介及耐药株在gyrA基因均检出有Ser-91→Phe突变并伴有Asp95或者Ala92位突变;6株检出有parC基因的86、87、91位点突变及其他位置的一些无义突变.结论gyrA基因突变是淋球菌耐喹诺酮类抗生素的重要机制,其中Ser-91→Phe更是引起对喹诺酮类耐药非常关键的突变,而parC基因的突变只会伴随gyrA基因突变同时出现,可能会对淋球菌耐喹诺酮类抗生素起促进作用.     

铜绿假单胞菌的耐药性变化及其DNA多态性分析

目的了解2001-2006年间铜绿假单胞菌的耐药性变化趋势并且对其DNA多态性进行分析。方法使用VITEK全自动微生物鉴定仪对铜绿假单胞菌临床分离株进行鉴定,药敏试验采用Kirby-bauer(KB)法,对分离的10株敏感株和8株耐药株进行随机引物PCR扩增。结果亚胺培南和头孢他啶的敏感性最强,头孢哌酮、哌拉西林、阿米卡星和环丙沙星的敏感率均超过50%;10株敏感菌分为8种基因型,8株耐药菌分为5种基因型。结论铜绿假单胞菌对多种抗菌药物较敏感,其耐药表型与其基因型之间具有一定的相关性。     

伤寒、副伤寒沙门菌耐药性以及viaB基因PCR分析

目的了解长沙地区伤寒、副伤寒沙门菌对抗生素的敏感性以及毒力基因的携带情况。方法纸片扩散法检测32株伤寒、副伤寒沙门菌对6种抗生素的敏感性;PCR扩增viaB基因片断进行检测。结果在测定的6种抗生素中,耐药性最高的为萘啶酸,耐药率达37.5%,而敏感性较高的为头孢噻肟和环丙沙星,敏感率分别为100%和93.8％。32株伤寒和副伤寒沙门菌经PCR检测后,有19株伤寒沙门菌在约469bp处,检测到阳性条带,其余1株伤寒以及12株副伤寒沙门菌未检出viaB毒力基因。结论第三代头孢和第三代的喹诺酮类抗生素仍可作为临床治疗伤寒副伤寒的首选药物,但应注意喹诺酮类药物的耐药趋势;Vi毒力基因在伤寒沙门菌中普遍存在,可广泛应用于疫苗制备和伤寒沙门菌的快速检测。     

199株淋球菌对环丙沙星和头孢三嗪的敏感性测定

目的 了解南宁地区淋球菌对环丙沙星,头孢三嗪的敏感性。方法 采用琼脂稀释法分别测定环丙沙星、头孢三嗪对199株淋球菌的最小抑菌浓度。结果 环丙沙星MIC范围为0．002－2mg/L,其中1999年MIC范围为0．25－≥16mg/L;14．5％菌株对环丙沙星敏感,41．71％为低度敏感,43．72％为耐药,其中1999年有4株淋球菌MIC≥16mg/L。头孢三嗪MIC为0．02－1mg/L,MIC50为0．03mg/L,MIC90为0．5mg/L;55.28％菌株对头孢三嗪敏感,39.20%为低度敏感,5．53％为耐药。其中,1999年末发现耐药菌株。结论 南宁地区已经不能把环丙沙星作为治疗淋病患者的首选药物;头孢三嗪是否仍能作为治疗淋病的一线药物,尚需进一步研究。     

acrAB外排泵对肺炎克雷伯菌耐环丙沙星作用的研究

目的研究临床分离的肺炎克雷伯菌中外排泵基因表达及其对环丙沙星耐药性的影响,明确外排泵在肺炎克雷伯菌对环丙沙星耐药中的作用。方法收集医院2014年9月-2015年2月临床标本中分离的肺炎克雷伯菌36株,采用VITEK-2Compact全自动微生物鉴定仪进行鉴定;K-B纸片扩散法对抗菌药物进行敏感性测定;用PCR方法检测菌株中的外排泵基因;用微量稀释法检测抗菌药物的最低抑菌浓度(MIC)以及泵抑制剂羰基氰氯苯腙(CCCP)存在情况下,肺炎克雷伯菌对环丙沙星MIC值的变化。结果 36株肺炎克雷伯菌中,有16株对环丙沙星耐药,耐药率为44.44%;采用PCR技术对16株耐药菌的外排泵acrAB基因进行检测,其中只有9株耐药菌株的检测结果为阳性,acrAB基因的检出率为56.25%;加入CCCP后,acrAB基因阳性株中,有5株(55.56%)MIC值下降4~16倍,2株(22.22%)MIC值下降两倍,还有2株(22.22%)MIC值未下降。结论 acrAB外排系统是肺炎克雷伯菌耐环丙沙星的一个重要机制,泵抑制剂CCCP可有效抑制acrAB基因的外排作用。     

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.     

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.     

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.     

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.