周期型马来丝虫GAPDH部分编码基因原核及真核表达载体的构建

[目的]构建我国流行的周期型马来丝虫3-磷酸甘油醛脱氢酶(BmGAPDH)部分编码基因原核和真核表达质粒以及基因序列分析,为进一步的研究奠定基础。[方法]根据GeneBank中马来丝虫GAPDH基因的已知序列设计引物,以周期型马来丝虫总RNA为模板,反转录PCR(RT-PCR)扩增目的编码基因。扩增产物经初步鉴定后将其克隆入pGEM-T载体,转化大肠杆菌(E.coli)DH5α,筛选阳性克隆,进行双酶切及PCR扩增鉴定,获得阳性重组质粒pGEM-BmGAPDH,经测序验证,并进行同源性比较。亚克隆至真核表达质粒pcDNA3.1(+),构建真核表达载体pcD-NA3.1(+)-BmGAPDH,转染COS-7细胞后进行RT-PCR验证。[结果]RT-PCR扩增出一条约877 bp大小的特异性条带,重组质粒双酶切的PCR结果与预期相符,DNA序列分析与GeneBank已知的基因序列同源性为99%。转染的COS-7细胞高水平表达BmGAPDH的mRNA,根据克隆的目的基因序列推导的氨基酸序列与GenBank登录的一致。[结论]成功构建了周期型马来丝虫3-磷酸甘油醛脱氢酶部分编码基因原核及真核表达载体,为进一步功能研究提供了条件。     

马来丝虫肌球蛋白基因序列及编码产物预测

目的 克隆周期型马来丝虫肌球蛋白(BmMyosin)基因,进行序列测定、分析及编码产物的B细胞表位预测.方法 依据公布的BmMyosin基因序列设计引物,以周期型马来丝虫总RNA为模板,反转录PCR(RT-PCR)扩增目的 编码基因.扩增产物经初步鉴定后将其克隆入pGEM-T载体,转化大肠埃希菌(E. coli)DH5α,筛选阳性克隆,进行双酶切及PCR扩增鉴定,获得阳性重组质粒pGEM-BmMyosin,经测序验证,并进行同源性比较.应用5种参数和方法 对其编码产物进行B细胞表位预测.结果 RT-PCR扩增出一条约1 292 bp大小的特异性条带,重组质粒双酶切的PCR结果 与预期相符,DNA序列分析与GeneBank已知的基因序列同源性为98.45%.经表位预测分析,BmMyosin的B细胞表位可能在287～300位、339～350位和416～422位氨基酸区域.结论 成功构建了周期型马来丝虫肌球蛋白重组质粒pGEM-T克隆载体,对其编码产物进行B细胞表位预测.为蛋白质特性分析及免疫学研究提供基础依据.     

日本血吸虫pcDNA3．1．（＋）-SjPGK重组质粒的构建及鉴定

目的 构建日本血吸虫中国大陆株磷酸甘油酸激酶基因片段(SiPGK)的真核表达重组质粒，寻找新的预防日本血吸虫病的候选疫苗分子。方法 采用逆转录一聚合酶链反应(RT-PCR)技术，从日本血吸虫总RNA中体外扩增SPGK基因片段；克隆人pMD18-T载体中，然后挑取阳性克隆经双酶切分析、PCR鉴定；亚克隆人真核表达载体pcDNA3．1( )中，阳性克隆经鉴定后进行脱氧核糖核酸序列测定；运用Blast程序，将测序结果及其推导的编码氨基酸序列与NCBI数据库在核苷酸水平和氨基酸水平进行同源性比较。结果 RT-PCR特异性扩增出一条长约830bp大小的条带；重组质粒pMD18-T-SPGK和pcDNA3．1( )-SPGK经双酶切和以质粒为模板进行PCR扩增，均可获得一条与RT-PCR产物一致的DNA片段；脱氧核糖核酸序列测定和分析结果表明：SjPGK基因片段长为830bp，与SmPGK的核苷酸同源性为85％，分值为672；氨基酸同源性为94％，分值为473。结论 成功地构建pcDNA3．1( )-SiPGK重组质粒，为构建其核酸癌苗提供了条件。     

微小隐孢子虫CRIP基因克隆与分析

目的 比对分析微小隐孢子虫南京(NJ)株亲环素-RNA相互作用蛋白(CRIP)与其他隐孢子虫株CRIP基因序列的差异.方法 根据GenBank微小隐孢子虫IowaⅡ株CRIP基因序列设计并合成2对引物,应用巢式聚合酶链反应(PCR)技术从微小隐孢子虫NJ株基因组DNA中扩增CRIP基因,并将其克隆到pMD18-T载体上,将重组质粒pMD18-T-CpCRIP进行PCR和双酶切鉴定后测序,应用生物信息学方法分析微小隐孢子虫NJ株CRIP基因与其他种属的CRIP基因序列同源性.结果 巢式PCR扩增获得的特异性CRIP基因序列,经PCR及双酶切鉴定确为pMD18-T-CpCRIP重组质粒;测序结果显示,该序列有119 bp,微小隐孢子虫NJ株CRIP基因全长为909bp,编码302个氨基酸;测序结果和同源性分析显示,中国微小隐孢子虫NJ株CRIP基因序列与国外的微小隐孢子虫IowaⅡ株同源性为98％;该隐孢子虫NJ株CRIP基因序列获GenBank登录号JQ396883.结论 微小隐孢子虫NJ株CRIP基因与其他微小隐孢子虫株存在基因变异.     

nm23-H1基因实时荧光定量PCR标准质粒的构建

目的：制备用于nm23-HI基因raRNA实时荧光定量PCR检测的质粒标准品。方法：通过PCR扩增出目的片断，纯化后T-A连接至pMD18-T载体，转化宿主菌E.coliDH5α，获得阳性克隆；通过PCR扩增、双酶切鉴定和测序分析，确认重组质粒完整正确；大量抽提重组质粒，测定其拷贝浓度，10倍稀释成梯度标准品，并进行荧光定量PCR检测分析。结果：nm23～H1基因目的片段成功重组至pMD18-T载体上，获得的重组质粒保持了目的片段的特异性和序列完整性。梯度浓度标准质粒的荧光定量PCR结果显示，循环阈值（Ct）与起始模板量的对数值之间有着良好的线性关系。结论：成功构建了nm23-H1基因实时荧光定量PCR质粒标准品。     

微小隐孢子虫腺苷酸激酶基因克隆及分析

目的获得微小隐孢子虫(Cryptosporidium parvum,Cp)南京(NJ)株的腺苷酸激酶(adenylate kinase,AK)基因的核苷酸和氨基酸序列,比对分析与其他隐孢子虫株AK基因序列的差异。方法采用昆明种小鼠建立微小隐孢子虫NJ株感染模型,根据GenBank微小隐孢子虫Iowa II株AK基因已知序列设计合成2对引物,应用巢式PCR方法从微小隐孢子虫NJ株基因组DNA中扩增AK基因,并将其克隆入pMD18-T载体;对重组质粒pMD18-T-CpAK经PCR及酶切鉴定后测序,应用生物信息学方法分析微小隐孢子虫NJ株AK基因与其他虫株的核苷酸和氨基酸序列差异。结果巢式PCR扩增获得特异的AK基因序列,酶切及PCR鉴定为正确的pMD18-T-CpAK重组质粒,扩增序列为903bp,含隐孢子虫AK全长基因663 bp;核苷酸序列测定及同源性分析表明,微小隐孢子虫NJ株AK基因与人隐孢子虫TU502 type 2株AK的同源性为99%,与微小隐孢子虫Iowa II株AK序列同源性为98%;进化树分析表明,微小隐孢子虫NJ株的AK基因与人隐孢子虫TU502 type 2株AK基因亲缘关系最近。结论成...     

阴道毛滴虫氢化酶体腺苷酸激酶基因真核表达载体的构建与鉴定

目的 构建阴道毛滴虫氢化酶体腺苷酸激酶(adenynate kimse,AK)基因真核表达载体并予以鉴定.方法 根据AK基因已知序列设计合成一对引物,应用PCR技术从阴道毛滴虫基因组DNA中扩增出AK基因,并将其克隆入pMD18-T Simple载体.阳性克隆的重组质粒经酶切及PCR鉴定后,用双脱氧链末端终止法进行基因序列测定.应用BLAST软件辅助分析所测基因与Genbank中阴道毛滴虫氢化酶体AK序列的同源性.克隆载体PMD-18T-AK经限制性内切酶BamHI和XbaI双酶切,得到含这2个酶切位点之AK DNA片段,T4连接酶连接到含有这2个酶切位点的真核表达载体pcDNA3.1( ),构建出重组真核表达载体pcDNA3.1( )-AK,经凝胶电泳鉴定、酶切鉴定、PCR鉴定证实DNA片段大小的正确性.结果 经凝胶电泳鉴定、酶切鉴定、PCR鉴定证实含大小正确的AK DNA片段.结论 成功地构建了基因真核表达载体.     

白色念珠菌hsp60基因克隆

目的:克隆白色念珠菌hsp60基因。方法:通过RT-PCR技术扩增白色念珠菌hsp60基因片段,纯化后与pMD18-T载体连接,转化并通过Amp、x-Gal、IPTG进行蓝白筛选,白色克隆提取质粒,SacⅠ和HindⅢ双酶切及PCR鉴定,基因测序。结果:RT-PCR扩增得到1701bp片断,重组质粒pMD18-T-hsp60双酶切后在2692bp和1701bp处可见到酶切片段,测序结果与GenBank中白色念珠菌hsp60基因比较,同原性达99%。结论:成功克隆白色念珠菌hsp60基因,为进一步研究其免疫保护机制及制备白色念珠菌疫苗奠定基础。     

幽门螺杆菌分离株iceA基因克隆及序列分析

目的 克隆幽门螺杆菌中国郑州市慢性萎缩性胃炎患者分离株MEL-Hp27 iceA基因,测序后对其进行序列分析.方法 根据iceA基因上下游基因序列设计引物,PCR扩增iceA基因,并将其连接至pMD19-T载体,测序后采用相关数据库和生物信息学软件对基因序列进行分析.结果 成功克隆幽门螺杆菌Hp27菌株iceA基因序列,扩增产物大小约为790 bp;重组质粒pMD19-T-iceA单酶切产生3 820 bp片段,双酶切产生3 000和820 bp的2个片段;Hp27iceA基因与大多数美国来源菌株同源性＞85%,与日本、印度等地区来源菌株同源性＜70%.序列分析结果表明,所克隆到的基因为iceA2亚型,与美国株Alaska strain 219、Alaska strain 213关系最近,同源性分别为87%和95%,与芬兰株Finland strain 9496等菌株存在聚类关系,同源性88%～93%,与CR9等其他菌株距离较远.结论 成功克隆幽门螺杆菌Hp27菌株iceA基因序列;不同地区幽门螺杆菌分离株的iceA基因间存在着一定差异.     

微小隐孢子虫20K亲环蛋白基因克隆及分析

目的 克隆微小隐孢子虫(Cp)南京株(NJ)的20K亲环蛋白(CyP)基因,并对其核苷酸和氨基酸序列进行分析.方法 采用昆明种小鼠建立微小隐孢子虫NJ株感染模型,根据微小隐孢子虫Iowa Ⅱ株20K CyP基因序列设计合成2对引物,应用巢式PCR技术从微小隐孢子虫NJ株基因组DNA中扩增20K CyP基因,并将其克隆到pMD18-T载体上,将阳性克隆重组质粒进行菌落PCR及双酶切鉴定;应用生物信息学方法分析微小隐孢子虫NJ株20K CyP基因与其他虫株核苷酸和氨基酸序列差异,并分析该基因蛋白结构域.结果 巢式PCR扩增得到特异的20K CyP基因,经PCR及双酶切鉴定获得了正确的pMD18-T-20K CyP重组质粒;测序结果显示,微小隐孢子虫NJ株20K CyP基因全长519 bp,编码173个氨基酸,该基因已登录GenBank,登录号为JQ284431;氨基酸序列分析表明,微小隐孢子虫NJ株与Iowa Ⅱ株20K CyP基因编码的氨基酸序列具有100％同源性;对20K Cyp基因进行蛋白结构域分析,显示该基因序列所编码的蛋白具有特异性类亲环蛋白A、B、H的肽脯氨酰顺反异构酶(PPIase)区域,该区域与人的亲环蛋白A、B、H具有相似性.结论 成功克隆微小隐孢子虫NJ株20K CyP基因,该基因具有高度保守性.     

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.     

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.     

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.     

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.     

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.     

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.