Vero-E6、MDCK、293细胞对SARS冠状病毒敏感性的研究

目的 研究Vero—E6、MDCK、293细胞对SARS冠状病毒的敏感性，为该病的病原学研究、诊断和疫苗制备奠定基础。方法 用Vero—E6、MDCK及293细胞对广东省部分SARS病人的咽拭子标本进行分离培养，并对分离物使用电镜、间接免疫荧光(IFA)及荧光定量聚合酶链反应(FQ—PCR)的方法分别检测细胞和(或)培养上清波中的病毒含量。结果 感染SARS病人的咽拭子标本后，Vero—E6细胞出现病变(CPE)最早，电镜中可观察到Vero—E6细胞中大量的病毒颗粒，IFA试验感染病毒的Vero—E6细胞与SAPS病人的恢复期血清呈强阳性反应，FQ—PCR结果显示Vero—E6感染细胞内的病毒含量10^8拷贝／ml，高于293细胞(10^6拷贝／ml)及：MDCK(104拷贝／ml)。结论 三种细胞对SARS相关病毒的敏感性不同，Vero—E6是SARS相关病毒最敏感的宿主细胞。     

广东省传染性非典型肺炎病例的SARS冠状病毒分离株的分子生物学鉴定

目的 对广东省部分传染性非典型肺炎(SARS)病例的SARS冠状病毒分离株进行鉴定，并初步建立SARS冠状病毒PCR检测方法。方法 采集临床诊断为SARS病例的咽漱液标本，进行多种细胞分离培养，对出现病变的细胞分离物采用冠状病毒特异引物通过逆转录聚合酶链反应(RT-PCR)及巢式聚合酶链反应(Nested—PCR)进行扩增，并对部分扩增片段进行序列测定，应用DNASTAR软件分析比较oN时采用间接免疫荧光(IFA)和ELISA法检测上述患血清中SARS冠状病毒Igc抗体。结果 对21例SARS患的细胞分离物进行PCR扩增，结果均阳性，其中12份患咽漱液标本PCR扩增结果也阳性，序列测定及基因分析表明，广东省SARS病例的病毒分离株为冠状病毒，其基因序列与WHO公布的SARS基因序列一致，氨基酸序列与目前已知的冠状病毒同源性为58％～76％。时对21例患进行血清学检测，其中IFA检测有9例阳性，ELISA检测有12例阳性。结论 从广东省部分SARS病例标本中分离的病毒株是一种新的冠状病毒，PCR检测具有早期、快速的优点。     

Hep-2细胞在严重急性呼吸综合征病原学检测中的应用研究

目的 应用人咽喉上皮癌细胞(Hep-2)对严重急性呼吸综合征(SARS)病例标本进行病原体检测与研究，为该病的预防与控制提供依据。方法 采用Hep-2细胞培养法，对2003年l～2月广东省收集的SARS病例的咽拭子等标本分离致病病原体，并应用电镜形态学、逆转录．多聚酶链反应(RT-PCR)扩增部分基因进行序列分析，并对分离的病原体进行研究。结果 132例SARS病例的3l份咽拭子、100份痰液和l份尸检肺组织标本中有73份标本致单层细胞出现“蚀斑病变”，细胞病变阳性率为55．3％，其中48h阳性率为36．4％。采用巢式PCR(Nested-PCR)对其中25份出现“蚀斑病变”细胞培养物进行检测，能扩增出冠状病毒的特异片段；对中2-18、中2-19等6份Nested-PCR产物进行基因序列分析，结果 显示其核苷酸序列与国内外公布的结果一致，氨基酸序列与已知的人或动物冠状病毒的同源性在58％～76％之间。通过电镜在SARS病例标本(中2-10)病变细胞及l份尸检肺组织标本中观察到衣原体样颗粒和病毒样颗粒。结论 从接种SARS病例标本的Hep-2细胞病变培养物中证实有冠状病毒。     

不同人群血清对人SARS冠状病毒和动物SARS样冠状病毒反应性的比较

目的 探讨不同人群血清中人SARS冠状病毒抗体和动物SARS样冠状病毒抗体所表达的意义及其之间关系。方法 应用人SARS冠状病毒和动物SARS样冠状病毒抗原片进行间接免疫荧光(IFA)定性和半定量试验,检测23份一般人群、25份动物市场从业人员和74份SARS病人的SARS冠状病毒IgG抗体阳性(ELISA法检测)血清样本,并进行比较分析。结果 23份一般人群、25份动物市场从业人员和74份SARS病人的血清样本的IFA阳性率分别为73．91％、68．00％和100．00％,在IFA阳性人群中其血清样本既能对人SARS冠状病毒也能对动物SARS样冠状病毒产生反应的分别占100．00％(17／17)、64．71％(11／17)和94．59％(70／74);70．59％(12／17)一般人群和76．47％(13／17)动物从业人员其血清中的动物SARS样冠状病毒抗体水平高于人SARS冠状病毒;而SARS病人血清中的人SARS冠状病毒与动物SARS样冠状病毒抗体水平以两者相同和前者高于后者为多,分别占56．76％(42／74)和33．78％(25／74)。结论 不同人群血清中的人SARS冠状病毒抗体和动物SARS样冠状病毒抗体两者之间均存在着一定的交叉反应现象,从血清学上提示了人SARS冠状病毒与动物SARS样冠状病毒之间存在着很高的同源性;人SARS冠状病毒抗体和动物SARS样冠状病毒抗体两者各自表达的意义是有所不同的,通过间接免疫荧光半定量试验可有助于区别感染者所染病毒的倾向性。     

广东省各类SARS病例标本实验室检测结果与临床诊断结果比较

目的 比较不同发病时间、有无明确接触史的SARS临床确诊病人和疑似病人实验室检测结果与临床诊断结果，分析实验室检测结果、流行病学资料和临床诊断之间的相互关系，为临床诊断提供更可靠的参考依据。方法 应用荧光定量PCR和巢式PCR技术检测病人咽拭子中SARS病毒特异基因，应用ELISA和间接免疫荧光法检测病人恢复期血清中的SARS病毒IgG抗体。结果 1～5月份，每月临床确诊病例PCR阳性率分别为：100％(2／2)、76．19％(16／21)、73．17％(30／41)、24．56％(14／57)和11．11％(2／18)，IgG抗体阳性率分别为100％(2／2)、78．57％(13／18)、58．33％(32／67)、30．30％(10／35)和9．52％(2／21)，阳性率逐月下降。4～5月份阳性率较低；1～4月份的临床确诊病例中，有明确接触史的病例，PCR和IgG抗体阳性率分别为73．58％(39／53)和74．42％(32／43)，无明确接触史的病例，PCR和IgG抗体阳性率分别为32．14％(27／84)和25．58％(22／86)，有无明确接触史临床确诊病例阳性率差异有显性。4～6月份，疑似病人PCR和IgG抗体的阳性率分别为11．89％(54／454)和7．78％(21／270)，阳性率很低。结论 综合临床症状、流行病学资料和实验室检测结果进行分析，可以得到更准确可靠的诊断结果。     

间接免疫荧光法在检测SARS冠状病毒特异性抗体中的应用

目的 利用间接免疫荧光技术(IFA)建立SARS冠状病毒(SARS—CoV)特异性抗体血清学诊断方法。方法 采用组织培养技术，用SARS病人的咽漱液样本，在Vero—E6细胞中培养，分离SARS冠状病毒；用已制备的SARS病毒抗原片与临床确诊为SARS的病人双相血清和正常人对照血清作用，再用荧光标记羊抗人IgM/IgG抗体与之结合，在荧光显微镜下观察荧光图像。结果 通过建立检测SARS冠状病毒特异性抗体的间接免疫荧光方法，在44份SARS临床病例标本中，检出IgG抗体阳性3l份，与临床诊断符合率为70．45％。31份IgG阳性者的急性期血清中IgM检出率为38．70％，IgM最早产生于发病第3天，发病7d以上的6例的IgM抗体均为阳性，滴度在发病12～15d达到高峰(1：80)；恢复期血清中IgG抗体最早产生于发病第8天，滴度在发病15～20d达到高峰(1：320～1：640)。97份正常人的血清标本中IgG抗体阳性率为3．09％，IgM抗体为阴性。结论 利用此方法，证实被SARS冠状病毒感染后，在机体中产生有特异性的IgM／IgG抗体；本方法检测结果与临床诊断符合率较高，可以用于早期临床诊断SARS病毒感染和辅助临床做出鉴别诊断。     

江苏省传染性非典型肺炎病原学检测研究

目的:建立传染性非典型肺炎(SARS)实验室检测方法,为SARS病例诊断和现场防治提供依据。方法:用逆转录套式PCR、实时荧光定量PCR检测SARS病毒核酸;酶联免疫法检测血清标本SARS病毒IgM抗体;部分PCR检测阳性或SARS病毒IgM抗体阳性病例的标本进行直接电镜观察;简并引物PCR检测冠状病毒属病毒核酸;鉴别诊断IFA检测血清中肺炎支原体等9种常见呼吸道感染病原IgM抗体,PCR检测军团菌以及甲、乙型流感病毒核酸。结果:检测各类临床标本506份。2003年全省报告临床诊断病例7例,5例检测结果阳性;逆转录套式PCR检测各类标本132份,阳性8份;对其中4份PCR扩增产物(108bp)进行了序列分析,与SARS病毒序列100%同源;实时荧光定量PCR检测各类标本30份,阳性3份;酶联免疫法检测血清标本101份,SARS病毒IgM抗体阳性4份;3个诊断病例的各类标本电镜检查发现冠状病毒样颗粒;IFA检测血清标本75份,嗜肺军团菌IgM抗体阳性9份,乙型流感IgM抗体阳性11份,两者同时阳性3份,其他病原体IgM抗体均为阴性。不明发热病例的标本21份简并引物PCR检测冠状病毒,2份咽拭子标本阳性;漱口液、尿液标本各15份PCR检测军团菌、漱口液25份PCR检测甲、乙型流感病毒结果均为阴性。结论:本研究建立的检测方法与临床诊断有比较好的符合性,对于临床诊断和防治工作具有重要的参考价值。PCR检测SARS-CoV特异性较好,而敏感性有待提高。     

荧光定量PCR检测传染性非典型肺炎冠状病毒的分析

目的 探讨荧光定量PCR在检测传染性非典型肺炎(SARS)冠状病毒(SARS—CoV)中的应用。方法 对2003年1～4月广州市各大医院送检的临床确诊或疑似的SARS病例以及密切接触的咽漱液和咽拭子进行荧光定量PCR检测。结果 从57份确诊患标本中检出SARS-CoV阳性38份，检出率为66．7％。14份密切接触标本中检出阳性7份。59份疑似患标本中检出阳性12份。SARS发病10～12d时SARS—CoV检出率最高，达87．5％。结论 荧光定量PCR能早期、快速检出SARS—CoV，临床符合率达66．7％，采样时间在发病1～12d最佳。     

广西野生动物SARS冠状病毒的感染状况及其意义

目的查明广西境内野生动物SARS冠状病毒感染状况。方法对广西境内15种117只野生动物及99只人工养殖的果子狸采用聚合酶链反应和血清学方法检测其病毒核酸。结果15种野生动物中鸟类及爬行类动物血清的SARS冠状病毒抗体阳性率分别为22．2％和20．0％，哺乳类动物SARS冠状病毒抗体阳性率为0，人工养殖的果子狸咽拭子及肛拭子标本未检出SARS冠状病毒核酸。结论野生动物中鸟类及爬行类动物SARS冠状病毒感染率较高，可能是SARS冠状病毒的自然宿主或储存宿主。     

检测SARS冠状病毒的套式RT-PCR方法的建立与初步应用

[目的]建立套式RT-PCR检测SARS冠状病毒的方法。[方法]从广东地区SARS患者尸解肺组织、咽拭子、嗽口水及本实验室分离的SARS冠状病毒（SAPS—CoV）组织培养上清中提取RNA，利用针对SARS冠状病毒多聚酶基因的特异性引物，进行逆转录及套式PCR扩增。扩增出的阳性片段连接入pGEM—T载体中，测序后比较其与其他已知SARS冠状病毒的同源性。[结果]从SARS患者尸解肺组织、咽拭子、嗽口水及SARS冠状病毒组织培养上清中均可扩增出阳性片段，经测序后证实是SARS冠状病毒特有序列。[结论]针对SARS冠状病毒多泵酶基因所建立的套式RT—PCR方法适用于临床标本及组织培养标本中SARS冠状病毒的检测。     

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.     

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.     

Assessing occupational and environmental exposure

Exposure assessment is a poorly understood component of the science of epidemiology. The relationship between exposure to chemicals and ill-health outcomes is often calculated using crude exposure measures such as ever/never exposed or duration. When investigating subtle effects, exposures need to be characterized much more fully in terms of intensity, frequency, duration and route. While occupational exposures tend to be much greater than those experienced from the wider environment there is a need to remember that, for many chemicals, exposure can occur occupationally, environmentally and through consumer use of products containing the material of interest. Inhalation exposure has generally been the traditional focus for most epidemiological investigations but there is now growing awareness of the importance of the dermal and ingested routes of contact and internalization. Quantification of the exposure also needs to be related to a biological mechanism of action and exposure metrics need to be selected accordingly. Occupational exposures can generally be measured using simple well-validated techniques. Environmental exposures require much more sensitive instruments and are more difficult to assess. Exposure modelling, particularly for the environmental fate of chemicals has undergone many recent developments and Monte Carlo techniques can be used to characterize model uncertainty and variability. This approach to exposure assessment can now be used in the setting of the wider environment and will enable a far better understanding of the relationship between exposure and disease.     

Mercury toxicity due to the smelting of placer gold recovered by mercury amalgam

A 19-year-old man developed tremor in both hands and fatigue after starting work at a placer gold mine where he was exposed to mercury-gold amalgam. Examination revealed an intention tremor, dysdiadochokinesis and mild rigidity. The 24-h urinary mercury concentration reached a peak of 715 nmol/l (143 ug/l) shortly before the clinical examination, after which he was removed from working in the gold room [Mercury No. Adverse Effect Level: 250 nmol/l (50 ug/l)]. On review 7 weeks later his tremor had almost resolved and the dysdiadochokinesis and rigidity had gone. The 24-h urinary mercury concentration had fallen to 160 nmol/l (32 ug/l). The principal exposure to mercury was considered to be the smelting of retorted gold with previously unrecognized residual mercury in it. The peak air concentration of mercury vapour during gold smelting was 0.533 mg/m3 (Mercury Vapour ACGIH TLV: 0.05 mg/m3 TWA). Several engineering and procedural controls were instituted. This episode occurred at another mine site, unrelated to Mount Isa Mines Limited.     

How Adults with Acquired Brain Damage Perceive Computer Training as a Rehabilitation Tool: A Focus-group Study

The aim of this study was to explore and describe how adult outpatients with acquired brain damage and referred to occupational therapy perceive computer training with the RehaCom programs, in order to evaluate the method of treatment as a tool in the rehabilitation of persons with cognitive disorders. By using focus-group discussions as a qualitative method of research when analysing the result, five themes with corresponding categories emerged, describing a development of understanding and learning about capacities. Themes describing how the participants could apply strategies to overcome shortcomings in daily occupations and the therapeutic role of the occupational therapist were identified as well. The result shows that a computer training program such as RehaCom can be used as an educational tool, for example, to guide a person who is trying to adopt compensatory strategies to avoid overload by taking pauses. It was found that anything the participants learned was also applicable to occupational performance in daily life.