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1.
目的研究北京生物制品研究所(北京所)和中国医学科学院医学生物学研究所(昆明所)生产的口服脊髓灰质炎(脊灰)减毒活疫苗(OPV)减毒位点的基因特征,对比Sabin标准株,从基因序列的基础上研究OPV是否安全有效,从而为中国维持无脊灰状态OPV的使用和免疫策略提供科学依据。方法随机选取生产的不同批次OPV,先进行病毒分离和扩增,用中和试验定型,分出Ⅰ、Ⅱ、Ⅲ型脊灰疫苗病毒,然后用聚合酶链反应(PCR)得到各型脊灰疫苗病毒的5′非编码区(5′NTR区)和VP1蛋白编码区基因核苷酸片段,测序后,与各型脊灰Sabin标准株进行比较分析。结果两个所生产的OPV各型疫苗病毒的5′NTR区核苷酸序列与标准Sabin株各型别5′NTR区无差别,同源性为100%;VP1区核苷酸序列比较,北京所与昆明所OPVⅠ型VP1区与SabinⅠ型VP1区核苷酸序列同源性为100%;北京所OPVⅡ型VP1区与SabinⅡ型VP1区比较,有5个碱基变化,同源性为99.45%,昆明所OPVⅡ型VP1区与SabinⅡ型VP1区比较,有6个碱基变化,同源性为99.34%;北京所与昆明所OPVⅢ型VP1区与SabinⅢ型VP1区比较,都有2个碱基变化,同源性为99.78%。北京所与昆明所生产的OPV,3个型别的5′NTR区和VP1蛋白编码区基因核苷酸序列与标准Sabin株比较,所有神经毒力位点未发生变化,未发生毒力回复突变。结论中国北京所和昆明所生产的OPV是安全有效的,应对如何停止使用OPV,如何用脊灰灭活疫苗取代OPV进行前期研究工作。  相似文献   

2.
目的:探讨脊髓灰质炎(脊灰)流行与野毒株性状的关系。方法:选择了1991年安岳县和1992年会东县各一例临床诊断为脊灰的患者,从其粪便标本中各分离出一株病毒,用微量中和试验进行血清学鉴定,PCR-RFLP法进行型内鉴定,对VP1区300个核苷酸进行测序,结果:血清学定型均为脊灰I型病毒,经PCR-RFLP法检测,判为野病毒,核酸序列分析证实两株病毒与Sabin I有明显差异为野病毒,两毒株间核酸序列不完全一致。有20个核苷酸的差异,结论:不同年份,不同地方流行株间的序列有差异,四川省脊灰流行与毒株间核酸序列的差异有关,但我国现行疫苗OPV能有效预防我省脊灰,基础免疫和强化免疫是预防和消灭脊灰的有力武器。  相似文献   

3.
脊髓灰质炎疫苗重组株病毒在我国的循环及其致病性   总被引:58,自引:18,他引:40  
我国自1994年10月以后已无脊髓灰质炎(脊灰)本土野病毒引起的病例.现在从急性弛缓性麻痹病例粪便标本中分离到的脊灰病毒都是3个血清型的疫苗衍生株,并以Ⅱ型为主.近几年每年Ⅱ型分离株的数量均多于同年I型株加Ⅲ型株之和.1997~1999年从贵州、云南省分离到的Ⅱ型疫苗株中,除了疫苗变异株外,还发现了不同血清型间的重组株,如VP1片段来自SabinⅡ,而3D片段分别来自SabinⅢ(S2×S3)和SabinI(S2×S1),它们的基因序列与脊灰疫苗株SabinⅡ型有差异.能从未服苗儿童的粪便标本中分离到这类毒株,表明在外环境中有这类毒株在循环.这些毒株可以致病,其致病性与该儿童是否接受了疫苗全程免疫有很大的相关性.重组株的发现提示我们,它们在自然环境中已有循环.从贵州省Ⅱ型病例发生时间和区域上看,病例有聚集分布的趋势,但目前尚处于小范围的循环中,其原因与对策有待进一步研究.  相似文献   

4.
目的分析一起疑似脊灰疫苗变异株病毒循环调查处置过程。方法进行病例核实诊断和个案调查,开展医院AFP病例主动搜索,评价AFP病例监测系统运转情况,调查密切接触者儿童粪便带毒率及脊灰疫苗接种率。结果在3例病例粪便标本中同时分离到Ⅲ型脊灰病毒,该病毒VP1区与Sabin疫苗株病毒相比,分别有0.44%、0.55%和0.44%的核苷酸变异。3例病例发病地点相距较远,均接种口服脊灰减毒活疫苗(OPV),密切接触者粪便标本未分离到脊灰病毒,当地儿童常规免疫接种率均处较高水平。结论脊灰疫苗变异株病毒未在当地发生循环。提高AFP监测系统敏感性、脊灰疫苗接种率和疫情应急能力,是有效阻止脊灰疫苗病毒变异株循环和脊灰野病毒输入的有效措施。  相似文献   

5.
目的对四川省发生的脊髓灰质炎(脊灰)疫苗高变异病毒(VHPV)/脊灰疫苗衍生病毒(VDPV)循环事件及其应急处置情况进行分析,为中国维持无脊灰状态口服脊灰减毒活疫苗(oev)的使用和在实现无脊灰目标后期,制定脊灰灭活疫苗(IPV)替代OPV的策略提供补充参考依据。方法运用现场流行病学调查、病例个案调查和标本检测、病例所在地及相邻地儿童OPV接种率快速评估、病例所在地及医院急性弛缓性麻痹(AFP)病例主动搜索、病例及密切接触者医学观察、密切接触者和周围健康儿童粪便标本病毒学监测、OPV应急强化免疫等方法进行综合处置。结果2011—08/2012—02从送检的阿坝县4名AFP病例粪便标本中分离到脊灰病毒(PV),经鉴定为Ⅱ型(PV—Ⅱ),其VP.编码区基因核苷酸序列与Ⅱ型Sabin脊灰疫苗株比较,分别有5、6、8、11个核苷酸变异,变异率分别为0.55%、0.66%、0.89%、1.22%,共享5个突变位点,且高度同源,根据WHO新修订的Ⅱ型VDPV鉴定标准,其中3例标本为VDPV,1例标本为VHPV,表明阿坝县发生了Ⅱ型VHPV/VDPV循环事件。事件发生后,病例所在地及相邻地区开展了现场流行病学调查、OPV强化免疫等多项应急处置措施,成功阻断了VHPV/VDPV循环传播,没有出现新发VHPV/VDPV病例。结论OPV低免疫覆盖率,是本次VHPV/VDPV循环事件发生的最主原因。为避免VHPV/VDPV循环的出现和传播,在切实加强常规免疫和提高接种覆盖率的同时,应尽快制定和实施IPV替代OPV方案。  相似文献   

6.
目的鉴定吉林省从急性弛缓性麻痹病例粪便标本中分离的1株VP1编码区Ⅲ/Ⅱ型疫苗重组脊髓灰质炎(脊灰)病毒[Vaccine-recombinant Poliovirus(PV),VRPV]。方法粪便标本采自1例2岁吉兰-巴雷综合征病例,使用转人PV受体的小鼠肺细胞系(Mouse Cell Line Expressing the Gene for the Human Cellular Receptor for PV,L20B)细胞和人横纹肌肉瘤(Human Rhabdomyosarcoma,RD)细胞进行病毒分离,阳性标本进行中和试验(Neutralization Test,NT)鉴定血清型,并通过逆转录-聚合酶链反应进行VP1编码区扩增和核苷酸序列测定,利用Bioedit软件对该序列结果与赛宾(Sabin)疫苗株PV进行核苷酸和氨基酸序列比对,分析重组位点的位置以及核苷酸和氨基酸的变异情况。结果该标本接种到RD和L20B细胞后,均发生了肠道病毒特征性病变,经血清学定型,结果为Ⅱ+Ⅲ型PV。VP1编码区核苷酸序列分析表明,其中的Ⅱ型PV与Sabin 2株PV比较,发生了1个核苷酸变异;Ⅲ型PV为VP1编码区Ⅲ型与Ⅱ型VRPV,与相对应的Sabin株PV相比,无核苷酸点变异,在VP1编码区重组的Ⅱ型PV序列为106个核苷酸。血清NT证明,该VRPV仍能被Ⅲ型完全中和,而不能被Ⅱ型中和。结论虽然Ⅲ型PV株中插入了Ⅱ型抗原位点NAg3a,但Ⅲ型PV株总体的型特异性抗原特征未发生改变。PV自然重组很少发生在衣壳蛋白编码区,发现的这株VRPV中和特性与Sabin株PV相比未发生变化。  相似文献   

7.
Ⅰ型疫苗衍生脊髓灰质炎病毒循环的发现和基因特点   总被引:8,自引:4,他引:8  
目的分析贵州省2004年Ⅰ型循环的疫苗衍生脊髓灰质炎(脊灰)病毒(cVDPVs)的基因特征,阐述cVDPVs的出现为全球消灭脊灰带来的挑战。方法2004年中国疾病预防控制中心(CDC)病毒病预防控制所国家脊灰实验室对各个省送检的每1个脊灰病毒分离株进行聚合酶链反应-限制性酶切片段长度多态性分析(PCR-RFLP)和酶联免疫吸附试验(ELISA)两种方法的型内鉴定。毒株型内鉴别显示异常时,则对该株病毒进行VP1编码区全基因的序列测定和分析。结果2004年从贵州省CDC送检的脊灰病毒株(或粪便标本的复核)中,共发现9株Ⅰ型疫苗衍生脊灰病毒(VDPVs)。这9株VDPVs从2例急性弛缓性麻痹(AFP)病例和4名接触者的粪便标本中分离到。其中8株分离于贞丰县挽兰乡的2例AFP病例和3名接触者,另外1株分离于贞丰县白层镇的1名AFP病例接触者。结论对9株cVDPVs的VP1编码区的序列测定和分析证实,它们有相似的核苷酸序列,共享5个核苷酸突变位点,说明VDPVs已发生了循环。cVDPVs很可能来源于2003年秋季的1次口服脊灰减毒活疫苗病毒的传播。对其中5株VDPVs的3D区和1株VDPV(8229-2)的全序列测定和分析,未发现脊灰病毒血清型之间的重组,也未发现与非脊灰肠道病毒的重组。  相似文献   

8.
目的描述山西省2007年Ⅰ型疫苗衍生脊髓灰质炎(脊灰)病毒(Vaccine-derived Poliovirus,VDPV)的基因特征,分析该VDPV的来源及对当地维持无脊灰的影响。方法对山西省2007年1例急性弛缓性麻痹(Acute Flaccid Paralysis,AFP)病例采集的双份粪便标本进行病毒分离,并对分离到的脊灰病毒(CHN11061株)进行VP1编码区基因核苷酸序列测定和分析,然后与国内外报道的其它Ⅰ型VDPV构建亲缘进化树。结果从该AFP病例的双份粪便标本中分离到2株Ⅰ+Ⅱ+Ⅲ混合型脊灰病毒,其中Ⅰ型毒株的VP1编码区基因核苷酸序列与PⅠ/赛宾(Sabin)疫苗株相比变异率≥1.0%,根据世界卫生组织(WHO)的标准鉴定为Ⅰ型VDPV。VP1编码区基因进化树图表明,山西省2007年Ⅰ型VDPV与国内外至今发现的其它VDPV进化距离较远,是新发现的VDPV,不属于循环着的(Circulating)VDPV(cVDPVs),同时无证据证明患儿为免疫缺陷患者,因此将这2株VDPV归类为Ⅰ型未分类的(Ambiguous)VDPV(aVDPV)。结论结合山西省2007年Ⅰ型VDPV的基因特征和当地口服脊灰减毒活疫苗(Oral Poliomylitis Attenuated Live Vaccine,OPV)免疫覆盖率情况,推测在当地存在1例免疫缺陷患者,由他/她长期携带并向外排泄变异的脊灰病毒,引起了山西省2007年VDPV感染事件。在脊灰消灭后期,应加强对可能存在的长期排毒者的发现和管理。  相似文献   

9.
目的对辽宁省2015年首次分离到的疫苗衍生脊髓灰质炎(脊灰)病毒(VDPV)进行病原学分析。方法采集所涉1例急性弛缓性麻痹(AFP)患者血清标本进行脊灰中和抗体检测;采集患者粪便标本,用L20B和RD细胞进行脊灰病毒分离;对脊灰病毒阳性分离物进行型内鉴定;对病毒VP1区进行基因测序和进化树分析。结果该例AFP患者血清脊灰Ⅰ、Ⅱ、Ⅲ型中和抗体滴度分别为1:4、1:4、1:8;患者的9份粪便标本中,2份标本的脊灰病毒分离阳性;阳性分离物的型内鉴定为PVⅡ-SL-Discordant;与Ⅱ型脊灰疫苗株(Sabin株)相比,两毒株VP1区序列核酸变异数分别为21个(2.3%)和22个(2.4%),鉴定为Ⅱ型VDPV。结论该AFP病例未持续排毒,其Ⅱ型VDPV分离株未引起循环。灭活脊灰病毒疫苗纳入免疫规划后,需加强脊灰病原学监测。  相似文献   

10.
目的 分析河北省2009-2011年急性弛缓性麻痹(AFP)病例及其密切接触者中脊髓灰质炎(脊灰)病毒分离株VP1编码区基因核苷酸变异情况,及时发现可能出现的疫苗衍生脊灰病毒(Vaccine-derived poliovrus,VDPV)及其引起的VDPV循环(Circulating VDPV,cVDPVs),为河北省维持无脊灰状态提供依据.方法 按照《世界卫生组织(WHO)脊灰实验室手册》的要求,对全省2009-2011年997例AFP病例及90例的接触者的粪便标本进行病毒分离与鉴定,分离的脊灰病毒送中国疾病预防控制中心(CDC)病毒病预防控制所国家脊灰实验室进行VP1编码区基因核苷酸序列测定与分析.结果 河北省2009-2011年,从24例AFP病例和7例AFP病例的密切接触者粪便标本中分离到脊灰病毒,将混合株进行单型分离,得到38株脊灰病毒,经国家脊灰实验室对脊灰病毒VP1编码区基因核苷酸序列测定,其中,36株发生突变,变异率均<1.0%,最多变异个数为5个.脊灰病毒阳性AFP病例男性明显高于女性,主要集中在小年龄组.结论 2009-2011年分离到的脊灰病毒均为疫苗株,局部地区出现高变异株,未发现VDPV,河北省继续保持无脊灰状态.  相似文献   

11.
This paper examines media coverage of 'breast cancer genetics', and explores its implications for public understanding. We present a content analysis of coverage in British newspapers and look at a variety of popular forms, including women's magazines, television soap opera and radio drama. Genetic/inherited risk receives a great deal of coverage across a wide range of media formats and outlets. Much of this attention has focused on individuals from 'high risk families' and dilemmas around prophylactic mastectomies. Through examining media coverage, combined with interviews with media personnel and their sources, we show why this story proved so attractive to the media and highlight the different production values which influence coverage. Finally, we introduce preliminary findings from focus group discussions to demonstrate how such 'human interest' framing has engaged audience attention and influenced public understandings. The paper concludes by highlighting the implications for analysing, predicting, and engaging with, media representations of science.  相似文献   

12.
Worker education in the primary prevention of occupational dermatoses   总被引:1,自引:0,他引:1  
This paper reports the evaluation of a skin care education programmeconducted on a fine chemicals manufacturing site where over1,000 employees are located. Approximately 60% are involvedin chemical manufacture. Over a 12 month period production staffreceived training in prevention of occupational dermatoses linkedto a site-wide poster initiative. The incidence of new casesof occupational dermatoses fell from 0.055 (70 cases in 1,277employees) to 0.021 (27 cases in 1,277 employees) before andafter the intervention respectively (p<0.0001). After otherfactors such as chemicals handled, observer bias and changesin reporting related to socioeconomic climate were taken intoaccount it is concluded that this study demonstrates the importanceof worker education as a tool for primary prevention of disease.Training materials such as video and poster presentations maybe effectively used in the chemical manufacturing industry asan adjunct to prevention and control of exposure to substanceshazardous to the skin. Such methods may also be used in otherindustries where there are significant risks of dermatoses.  相似文献   

13.
To understand geographic variation in travel-related illness acquired in distinct African regions, we used the GeoSentinel Surveillance Network database to analyze records for 16,893 ill travelers returning from Africa over a 14-year period. Travelers to northern Africa most commonly reported gastrointestinal illnesses and dog bites. Febrile illnesses were more common in travelers returning from sub-Saharan countries. Eleven travelers died, 9 of malaria; these deaths occurred mainly among male business travelers to sub-Saharan Africa. The profile of illness varied substantially by region: malaria predominated in travelers returning from Central and Western Africa; schistosomiasis, strongyloidiasis, and dengue from Eastern and Western Africa; and loaisis from Central Africa. There were few reports of vaccine-preventable infections, HIV infection, and tuberculosis. Geographic profiling of illness acquired during travel to Africa guides targeted pretravel advice, expedites diagnosis in ill returning travelers, and may influence destination choices in tourism.  相似文献   

14.
Two hazard risk assessment matrices for the ranking of occupational health risks are described. The qualitative matrix uses qualitative measures of probability and consequence to determine risk assessment codes for hazard-disease combinations. A walk-through survey of an underground metalliferous mine and concentrator is used to demonstrate how the qualitative matrix can be applied to determine priorities for the control of occupational health hazards. The semi-quantitative matrix uses attributable risk as a quantitative measure of probability and uses qualitative measures of consequence. A practical application of this matrix is the determination of occupational health priorities using existing epidemiological studies. Calculated attributable risks from epidemiological studies of hazard-disease combinations in mining and minerals processing are used as examples. These historic response data do not reflect the risks associated with current exposures. A method using current exposure data, known exposure-response relationships and the semi-quantitative matrix is proposed for more accurate and current risk rankings.  相似文献   

15.
BACKGROUND: A strong association between workplace bullying and subsequent anxiety and depression, indicated by empirical research, suggests that bullying is an aetiological factor for mental health problems. AIMS: To evaluate levels of stress and anxiety-depression disorder developed by targets of workplace bullying together with outcome at 12 months and to characterize this population in terms of psychopathology and sociodemographic features. METHODS: Forty-eight patients (36 women and 12 men) meeting Leymann Inventory of Psychological Terror criteria for bullying were included in a prospective study. Evaluations were performed at first consultation and at 12 months using a standard clinical interview, a visual analogue scale of stress, the Hospital Anxiety and Depression (HAD) scale, the Beech scale of stress in the workplace and a projective test (Picture-Frustration Study). RESULTS: At first consultation, 81% of patients showed high levels of perceived stress at work and 83 and 52% presented with anxiety or depression, respectively. At 12 months, only 19% of working patients expressed a feeling of stress at work. There was a significant change in symptoms of anxiety while there was no change in symptoms of depression. Stress at work and depression influenced significatively capacity to go back to work. At 12-month assessments, workers showed a significantly better score on the HAD scale than non-workers. Over half the targets presented a neuroticism-related predominant personality trait. CONCLUSION: Workplace bullying can have severe mental health repercussions, triggering serious and persistent underlying disorders.  相似文献   

16.
BACKGROUND: The incidence of malignant mesothelioma in Britain is predicted to rise over the next 15-25 years because of past failure to protect the workforce against inhalation of asbestos. In British Naval dockyards, alternative insulation materials and respiratory protection were introduced from the mid-1960s. Aims This study was carried out to investigate the effects of these control measures on mesothelioma deaths in dockyard workers. METHODS: Cases of mesothelioma of the pleura and peritoneum between 1979 and 1999 in workers from the Devonport Naval Dockyard, south-west England, were sought from coroners' and medico-legal records. RESULTS: Three hundred and one cases were identified, 7% peritoneal. The peak incidence occurred in 1991 with 25 cases per annum (quadratic model fit R(2) = 74.2%, P < 0.001) and we predict that by 2003 the incidence will fall to fewer than five cases per annum. The mean time between first exposure and presentation was 48.5 years [95% confidence interval (CI) = 47.3-49.8], but this was significantly shorter in the more heavily exposed trades, when compared with the less heavily exposed (42 years, 95% CI = 39.0-45.0, versus 49.5 years, 95% CI = 48.2-50.9). Those with higher exposure were also at significantly greater risk of peritoneal disease (P < 0.023, Fisher's exact test). CONCLUSION: The reduction in incidence of mesothelioma is greater than can be accounted for by reduction in numbers of dockyard workers over the last 50 years. Changes in insulation materials and improved industrial hygiene measures introduced into the Devonport Dockyard from the mid-1960s have resulted in an earlier decline in the incidence of malignant mesothelioma than that predicted for the British workforce as a whole.  相似文献   

17.
Organophosphate toxicity and occupational exposure   总被引:5,自引:0,他引:5  
The ubiquitous organophosphates present a continuing health hazard in agriculture, public health eradication programmes and as chemical warfare agents. Despite significant progress in understanding the potential mechanisms of toxicity far beyond the commonly accepted mechanism of cholinesterase inhibition in intentional exposures, the precise health effects following occupational exposures are yet to be completely defined. A much greater understanding exists of the clinical features of organophosphate poisoning. These are characterized by a triphasic response involving an initial acute cholinergic phase, an intermediate syndrome (both associated with high mortality) and a disabling but non-lethal delayed polyneuropathy. The delayed polyneuropathy may occur in the absence of the cholinergic or intermediate phases. However, progress is still required in order to improve the quantification and assessment of occupational exposures and the implementation of appropriate preventive measures. Finally, evidence-based guidelines for appropriate or optimal therapeutic interventions following poisoning are required urgently and collaborative work with colleagues in developing countries, where the occurrence of organophosphate exposures is more frequent, may provide the answers.  相似文献   

18.
This report documents a case series of miliaria rubra of the lower limbs in miners at a deep underground metalliferous mine in tropical arid Australia. During the summer months of February and March 1999, all cases of miliaria rubra of the lower limbs in underground miners seen at the mine's medical centre were clinically examined and administered a questionnaire. Twenty-five patients were seen, an incidence of 56.4 cases per million man-hours. Miliaria rubra was most often located between the ankle and knee (88% of cases). Twenty-four percent had concurrent folliculitis and 20% had concurrent tinea. Thirty-two percent had a personal history of asthma. Walking through ground-water and splashing of the legs was common. Three to 4 weeks of sedentary duties in air conditioning was generally required to achieve resolution of miliaria rubra. The incidence of miliaria rubra of the lower limbs is 38% of the incidence of heat exhaustion at the same mine. The length of disablement is greater, however. Atopics may be at increased risk of miliaria rubra. Control measures are discussed.  相似文献   

19.
The starting point for any research project should be a question.Once this has been defined and the relevant scientific literaturereviewed, a protocol should be drawn up. This will be used notonly as a guide to the conduct of the study and in the preparationof the final report, but also in seeking any financial supportand approvals that are required for the investigation. A protocolis normally arranged in sections covering the background tothe study, the question(s) that it will address, the methodsthat will be used for the collection and analysis of data, thestatistical power of the investigation (where relevant), anyethical considerations, and the financial input that will beneeded. A pilot study is often helpful where aspects of thestudy method are untried or of uncertainvalidity.  相似文献   

20.
BACKGROUND: High levels of stress have been attributed to the conditions of police work, but there is little empirical evidence for this. AIMS: To develop a new instrument to measure job stress in the police; to assess the most severe and frequent police stressors; to compare levels of stress according to the demographic and organizational factors; and to study stress in relation to personality traits, work locus of control and coping strategies. METHODS: A comprehensive nationwide questionnaire survey of 3272 Norwegian police at all hierarchical levels, including the Norwegian Police Stress Survey (NPSS), the Job Stress Survey, the Basic Character Inventory, the Work Locus of Control Scale, and the Coping Strategies Scale. RESULTS: Work injuries were appraised as the most stressful but least frequent stressor and job pressure was reported the least severe but most frequent stressor. Females experienced job stressors less frequently, but appraised them as more severe than men did. Older police officers reported more job pressure severity and fewer work injuries. The police in districts where peer support was planned but not implemented, and who worked in districts with more than 50,000 inhabitants, perceived the lack of support more severely than others. The correlations between stress and personality traits, work locus of control, and coping were moderate. CONCLUSIONS: The NPSS captures police-specific stressors that are not adequately measured by global stress instruments. The study of stress in police work should preferably involve a nationwide use of police-specific stress instruments.  相似文献   

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