重组痘苗病毒嵌合巨蛋白的免疫学研究

目的　pSFJ1 6与pSFJ38均是以牛痘病毒包涵体 (ATI)启动子和分别串联的 1 6个和 38个p7 5突变型早期启动子为基本构件组成的复合型启动子 (ATI-p7 5)、痘苗病毒复制非必需区血凝素 (HA)基因为侧翼的痘苗病毒表达载体。分别插入编码艾滋病病毒 (HIV - 1 )外膜蛋白env、核心蛋白gag与编码干扰素 (IFNα - 2b)基因 ,观察其表达产物诱导的机体内产生抗体效价的变化规律。方法　利用分子克隆技术构建重组质粒 ,经脂质体转染与野生型痘苗病毒在Cos- 7细胞内同源重组 ,筛选、纯化、获得重组痘苗病毒vJ1 6env/IFNα - 2b和vJ38gag/IFNα - 2b。免疫小鼠后 ,经间接ELISA分折免疫小鼠血清抗体的OD4 90 值变化。结果　免疫小鼠后体内抗体的OD4 90 值 ,实验组与阴性对照组平均数有显著性差异 (P <0 0 5) ,实验组与阳性对照组之间无显著性差异 (P >0 0 5)。结论　重组痘苗病毒vJ1 6env/IFNα - 2b和vJ38gag/IFNα- 2b免疫小鼠后可诱导机体产生高滴度的抗HIV - 1env、gag与IFNα - 2b巨蛋白抗原的抗体 ,蛋白稀释度与血清抗体OD4 90 值呈负相关     

Gag/IFNα-2b融合基因在痘苗病毒中共表达研究

目的　本实验将编码AIDS病毒 (HIV -1)核心蛋白gag与编码干扰素 (IFNα -2b)基因插入以痘苗病毒复制非必需区血凝素 (HA)基因为侧翼 ,牛痘病毒包涵体 (ATI)启动子和串联的p7 5突变型早期启动子为基本构件的痘苗病毒表达载体 (pJ3 8) ,经与野生型痘苗病毒在细胞内同源重组 ,获得具有生物活性的重组痘苗病毒vJ3 8gag/IFNα -2b。方法　经免疫荧光、Dot -ELISA、SDS -PAGE、Western -blot等方法检测表达产物 ,分析免疫小鼠后血清抗体IgGOD4 90 值与T淋巴细胞的变化。结果　vJ3 8gag/IFNα -2b能表达Gag/IFNα -2b融合蛋白 ,分子量约 60kDa。免疫小鼠实验表明血清抗体IgGOD4 90 值、CD+ 4、CD+ 8T淋巴细胞计数的组间比较 (P <0 0 0 1) ,含IFNα -2b与单纯vJ3 8gag组相比 (P >0 0 5) ,但呈渐进性增高的趋势。 结论　重组痘苗病毒表达的gag/IFNα -2b融合蛋白具有良好的免疫原性和免疫反应性     

Env/IFNα-2b融合基因在痘苗病毒中共表达研究

目的：本实验选择的真核表达载体pJ16，是以痘苗病毒复制非必需区血凝素（HA）基因为侧翼，以牛痘病毒包涵体（ATI）启动子和串联的p7.5突变型早期启动子为基本构件的痘苗病毒表达载体。插入编码AIDS病毒（HIV－1）外膜蛋白env与编码干扰素IFNα-2b基因。方法：经与野生型痘苗病毒在细胞内同源重组，排选HA^-斑。获得重组痘苗病毒vJ16env/IFNα-2b。经免疫荧光、Dot blot、SDS-PAGE、Western blot和免疫小鼠后血清抗体IgG OD值检测。结果：vJ16en/IFNα-2b能表达Env-IFNα-2b融合蛋白，分子量约100kDa。免疫小鼠实验，血清抗体IgG OD值组间均数比较（P＜0．001），含IFNα－2b与vJ6env组比较（P＞0．05），但有增高趋势。结论：重组病毒表达的Env-IFN融合蛋白具有良好的反应原性和免疫原性。     

HIV Ⅰ型外膜蛋白/干扰素A-2b的构建与表达

目的 构建艾滋病病毒外膜蛋白（env）与干扰素（IFNα-2b）融合基因表达质粒，观察其在痘苗病毒中共表达结果。方法 利用基因重组技术，将IFNα-2b基因片段插入到env基因的nt8383位点，经脂质体转染与血凝素阴性蚀斑筛选，挑出重组痘苗病毒。经免疫荧光、免疫印迹（Western blot）和斑点酶联免疫吸附试验（Dot-ELISA）鉴定表达产物。结果 间接免疫荧光实验结果显示，转染重组质粒的细胞表面有绿色荧光。Westem-blot与Dot-ELISA结果均显示，重组质粒转染细胞的裂解物中存在表达的env／IFNα-2b蛋白。结论 成功地构建了重组真核细胞表达质粒，表达的蛋白具有良好的免疫原性与免疫反应性。     

HIV-1 gag/IFNα-2b表达产物的免疫原性研究

目的构建艾滋病病毒核心蛋白（gag）与干扰素（IFNα-2b）融合基因表达质粒,观察其与痘苗病毒共表达的结果,研究其意义。方法利用基因重组技术,将IFNα-2b基因片段插入到gag基因的nt 531位点,经脂质体转染与血凝素阴性蚀斑筛选,挑出重组病毒。经免疫荧光、蛋白印迹分析（Western blot）和斑点酶联免疫（Dot ELISA）鉴定表达产物。结果间接免疫荧光实验显示,转染重组质粒的细胞表面有绿色荧光。免疫印迹实验与Dot ELISA结果均显示,转染重组质粒的细胞裂解物中存在表达的gag/IFNα-2b蛋白。结论成功地构建了重组真核细胞表达质粒,表达的蛋白具有良好的免疫原性与免疫反应性。     

HIV-1 AE重组型疫苗构建及免疫原性研究

目的利用AE亚型的膜蛋白,研发抗HIV-1AE重组型的疫苗并进行免疫原性评价。方法构建表达中国流行株97CNGX2F（HIV-1 AE2F）包膜蛋白gp140的重组痘苗病毒rVVT140AE。使用表达gp140的DNA疫苗和rVVT140AE用初免-加强方式免疫小鼠。免疫结束后第2周处死小鼠,分别检测特异性抗体滴度和特异性T细胞反应。结果本疫苗所活化的特异性抗体滴度在3 200和51 200之间,几何平均值为11 143;总T细胞免疫反应强度为（1 918±442）SFCs/10^6脾细胞,其中针对env1、env2、env3、env4肽池的免疫反应强度分别为（1 280±330）SFCs/10^6脾细胞,（66±16）SFCs/10^6脾细胞,（163±34）SFCs/10^6脾细胞和（409±96）SFCs/10^6脾细胞,均显著高于空载体对照组（〈10 SFCs/10^6脾细胞）。结论本实验构建的HIV-1 AE2F株包膜蛋白gp140重组痘苗病毒疫苗可作为针对我国HIV-1流行株的候选疫苗免疫原。     

多种维生素矿物质补充剂对小鼠免疫功能的影响

目的研究多种维生素矿物质补充剂对BALB/c小鼠免疫功能的影响.方法实验共分3个免疫组,每个免疫组分4个剂量组,分别灌胃给予BALB/c小鼠不同剂量(0、0.09、0.18和0.36 g/kg体重)的多种维生素矿物质补充剂,试验周期为45天.试验结束分别测定细胞免疫功能(包括ConA诱导的小鼠淋巴细胞转化实验和迟发性变态反应实验)、体液免疫功能(包括抗体生成细胞数和半数溶血值HC50测定)、单核-巨噬细胞吞噬功能(包括小鼠腹腔巨噬细胞吞噬鸡红细胞实验和碳廓清实验)和NK细胞活性,并进行T淋巴细胞亚群分化实验(流式细胞术测定)和血清IL-2水平测定.结果细胞免疫功能测定结果显示,0.18和0.36 g/kg体重剂量组小鼠足跖肿胀明显高于对照组;体液免疫功能测定结果显示,0.09、0.18和0.36 g/kg体重剂量组半数溶血值显著高于对照组,并呈剂量-反应关系;巨噬细胞吞噬鸡红细胞实验结果表明,0.09 g/kg体重剂量组吞噬率显著升高;T淋巴细胞分化亚群实验表明,各剂量组的CD4 T淋巴细胞数量和CD4/CD8比值明显升高,并呈剂量-反应关系.结论该多种维生素矿物质补充剂可增强小鼠的体液免疫和细胞免疫功能,促进T淋巴细胞亚群分化,具有增强机体免疫功能的作用.     

甲型肝炎灭活疫苗(L-8株)口服及腹腔注射Bal b/c小鼠的免疫反应评价

目的　比较评价甲型肝炎(甲肝)灭活疫苗(L 8株)不同途径接种Balb/c小鼠所诱导产生的免疫效应。方法将32 0EU/0 5ml的实验疫苗1次口服及腹腔注射免疫实验动物,于2周、4周时收集血液样本,用酶联免疫吸附试验(ELISA)方法检测抗体反应,同时动态检测免疫小鼠外周血T淋巴细胞亚群及肿瘤坏死因子(TNF) α、干扰素(IFN) γ。结果　不论是腹腔注射或是口服免疫均能诱导产生良好有效的体液免疫效应。腹腔免疫后CD+ 4 T细胞百分比轻微下降,而CD+ 8T细胞百分比上升趋势及幅度明显,CD+ 4 /CD+ 8比值明显下降;而口服免疫小鼠外周血CD+ 4 T细胞百分比持续上升,CD+ 8T细胞百分比亦同步升高,两者上升幅度基本一致,CD+ 4 /CD+ 8比值无明显改变。另外,两种途径免疫接种均可诱导产生高滴度的内源性IFN γ。结论　有必要对甲肝灭活疫苗口服免疫的机制及其开发利用作进一步的研究。     

环磷酰胺致小鼠免疫功能低下模型建立与评价

目的 建立环磷酰胺致免疫低下模型,应用流式细胞术检测小鼠自然杀伤细胞(NK)细胞分化抗原CD69⁺/自然杀伤细胞G2D受体(NKG2D⁺)和T淋巴细胞分化抗原CD69⁺/CD3⁺评价其免疫低下动物模型中的应用.方法 以环磷酰胺强化注射、少量多次注射、一次大剂量注射分别建立免疫低下模型,30 d后处死,取外周血和脾,分别检测小鼠外周血自然杀伤细胞(NK)亚群CD69⁺/NKG2D⁺和外周血T淋巴细胞CD69⁺/CD3⁺亚群,同时进行脾NK细胞活性测定,ConA诱导的小鼠脾淋巴细胞转化试验,观察环磷酰胺对外周血T淋巴细胞、NK细胞免疫功能的影响.结果 环磷酰胺强化注射、少量多次注射均可使小鼠外周血和牌的活化的NK细胞和T淋巴细胞比例及T淋巴细胞转化增殖能力、脾NK细胞活性降低.结论 环磷酰胺强化注射可以长时降低小鼠细胞免疫功能的作用,适用于建立长期免疫低下模型;流式细胞术检测T淋巴细胞和NK细胞分化抗原在免疫调节功能评价中有较好应用价值.     

HIV/HCV共感染对HIV一1生物学特性影响的研究

目的研究有偿献血人群HIV／HCV共感染对HIV-1基因离散率、病毒载量、CD4 T淋巴细胞等生物学特性影响。方法扩增HIV-1 env基因C2～V3区,Clustal W和Phylip软件计算基因离散率,NASBA方法检测HIV-1病毒载量,采用Coulter公司的Epics XL流式细胞计数仪检测CD4 细胞数,用SPSS软件t检验分析HIV／HCV共感染对HIV-1生物学特性的影响。结果HCV共感染与非共感染人群的HIV-1平均基因离散率为7．95％、15．73％(P<0．001),平均病毒载量为4．61、4．45(P=0．522),平均CD4 T淋巴细胞数为308、251(P=0．161)。结论该有偿献血人群中HIV／HCV共感染对HIV-1基因离散率有影响,而对病毒载量、CD4 T淋巴细胞无影响。     

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.