TTV致病性的研究

一年前在日本发现的经输血传播的病毒(TTV)呈全球性分布。Makto等发现,这一病毒基因组由单链线状DNA组成。他们认为,TTV可能是一种细小病毒,这与其缺乏外膜包裹相一致,但TTV比细小病毒的浮力密度轻得多,基因组也明显较大,而且已证实TTV与已知的同组病毒间无序列同源性。 TTV是否致病已成为目前关注的焦点,但就象庚型肝炎一样,TTV与疾病的关系远未明了。Roman等在TTV致病性的研究中发现,成人慢性肝病患者或HCV感染者的血清标本中,TTV DNA的阳性率为10％～38％,但无统计学意义。有三组研究分别报道,日本供血者中TTV DNA的阳性率为     

河北部分地区不同人群TTV感染的研究

TT病毒（TT virus，TTV）是一种单链DNA病毒，自1997年底日本学者从1例输血后非甲非戊型肝炎病人的血清中分离出TTV以来，各国学者对TTV的研究日益深入，1998年Okamoto等报道了TTV全基因序列。为了解TTV在河北省不同人群中的感染状况，分析TTV与肝病的关系，笔者对正常人群和甲、乙、丙型、不明原因肝炎患者及其他肝病患者进行了TTV DNA检测，结果如下。     

一种新的肝炎病毒TTV研究近况

在急慢性输血后肝炎、散发性肝炎、暴发性肝炎及肝硬变病例中,有相当部分病例无法用已建立的甲、乙、丙、丁、戊型肝炎的实验室诊断方法进行病原学分型.1993年国际肝炎会议上不少学者提出可能存在已型肝炎病毒(HFV)[1],但至今未能克隆出HFV的基因,该病毒是否存在目前尚有争议.1995年美国学者先后报道发现了HGV/GBV-C[2,3],但越来越多的研究表明,该病毒可能不是原因不明非甲-戊型肝炎的主要病毒,可能还存在尚未发现的致急慢性肝炎的其他病毒.1997年日本学者Nishizawa[4]等在一例输血后肝炎患者血清中发现一种新的可能与输血后肝炎相关的单链的DNA病毒,由于该病毒是从一名发生输血后肝炎的日本患者血清中克隆出来,该患者名字为TT,TT也是Transfusion Transmitted(输血传播)的缩写,因此该病毒被命名为TTV.其后,英国[5]、新西兰[6]、中国[7]等也相继报道发现TTV,表明TTV感染呈全球性分布.     

频繁接受输血患者中的TTV检出率及其临床意义

频繁接受血制品输注的血液病患者常并发肝病。尽管输注前已对血制品进行HBV及HCV筛检,但上述患者的输血后肝炎仍是有待解决的问题。Nishizawa等(1997年)从1例输血后肝炎患者血清中克隆出一种新的DNA病毒,命名为TTV,此后在5例输血后非甲～庚型肝炎患者血清中,有3例检出TTV DNA,血清TTV滴度与ALT水平     

接受透析治疗患者感染TTV的临床研究

近年,从原因不明的输血后肝炎患者的血中发现了新DNA病毒——TT病毒(TTV),约从半数非甲～庚型重症肝炎和慢性肝病患者中检出该病毒。据报道,在接受透析治疗患者中,输血、给予血制品或频繁验血等,可使乙型肝炎病毒(HBV)、丙型肝炎病毒(HCV)或庚型肝炎病毒(GBV-C/HGV)的感染率升高,但有关TTV感染的状况及其意义尚不明确。为了解透析治疗患者TTV感染的情况,作者对60例透析治疗患者检测TTV DNA,并对透析时间、有无输     

熔点曲线法研究TTV肝炎患者中TTV准种与其临床分型的关系

目的研究TTV肝炎患者中TTV准种及其与患者不同临床分型的关系。方法采用巢式荧光实时多聚酶链式反应(PCR)扩增TTVDNA,收集TTV DNA阳性的慢性肝炎病例52例,其中轻度、中度、重度分别为15例、17例、20例;慢性重型肝炎患者18例;献血员15例。采用熔点曲线方法进行TTV准种检测。结果TTV肝炎患者中度、重度和重型组中熔点曲线波峰数量显著多于献血员和慢性TTV肝炎轻度组(P<0.05),重度和重型组熔点曲线波峰数量显著多于中度组患者(P<0.05)。但重度组患者TTVDNA熔点曲线波峰数量与重型组相比较无显著差异(P>0.05)。结论TTV存在病毒准种,TTV准种感染的复杂性可能是TTV肝炎患者病情严重程度有关,准种越复杂病情越严重。     

输血与TTV感染 FREE

1997年,日本学者首次发现并报告了输血传播病毒（transfusion transmitted virus,TTV）,其是一种引起人类输血后肝炎的新的DNA病毒,是继甲、乙、丙、丁、戊及庚型肝炎病毒之后新近发现的一种可经血源传播的病毒,在各型肝炎患者的血液中广泛分布。1998年,周育森等在我国10例临床诊断为非甲-非戊型肝炎患者的血清标本中,     

应用原位杂交技术检测人肝组织中输血传播病毒核酸

目的　探讨输血传播病毒 (transfusiontransmittedvirus,TTV)在人肝组织中的分布状况及其意义。方法　采用地高辛标记探针 ,对肝组织中的TTV基因进行原位杂交定位检测。结果　原位杂交染色阳性者为细胞核团块状。 5例正常人中有 1例阳性 ,5例乙型肝炎患者有 3例阳性 ,4例丙型肝炎患者有 2例阳性 ,3例戊型肝炎患者有 1例阳性。结论　TTV可感染肝细胞并在肝细胞核内复制。正常人及不同型肝炎病人的肝细胞内均可感染TTV。     

肝病患者中存在一种新的人类DNA病毒——TTV

1997年,日本学者从1例输血后肝炎患者血清中分离出一种新的人类病毒,称为“输血传播病毒”(TTV)。据报道,暴发型非甲～戊型肝炎患者中TTV DNA检出率为47％,原因未明的慢性肝病患者中TTV DNA检出率为46％,提示TTV可能是某些原因未明肝病的致病原因。但本文报道英国肝病患者中检出TTV并分析其与肝损伤的联系。     

存在于供血员和血制品中的TTV

一种新发现的DNA病毒——输血传播病毒(TTV)已证实与输血后肝炎的病因有关。作者就英国供血员中TTV病毒血症的发生率和血制品受TTV污染的程度进行了调查。同时,还对TTV在原因不明的暴发型肝衰竭(FHF)中致病的可能性作了研究。 从供血员和FHF患者的血浆及血制品(凝血因子Ⅷ见和Ⅸ的浓缩物、免疫球蛋白)中     

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.