青海省人间鼠疫病原学研究及菌株溯源分析

目的　对1958--2012年青海省人间鼠疫流行期间自鼠疫患者和尸体中分离的129株鼠疫菌进行病原学研究。方法　采用常规方法和分子生物学技术对鼠疫菌进行病原学研究,同时采用差异区段（DFR）基因分型技术对2004年囊谦县、2009年兴海县人间肺鼠疫暴发疫情进行溯源分析。结果　119株鼠疫菌中,205株属青藏高原型菌株,6株属祁连山型菌株,8株菌具有特殊生化特性;84．03％（100／219）的鼠疫菌具有4个毒力因子（F1⁺、Pst I⁺、VW⁺、Pgm⁺）。测试的74株菌中,72株（97．30％）为强毒菌;携带大质粒52×10⁶、65X 10⁶、92×10⁶的菌株主要分布于海南、海北、海西、玉树、果洛、黄南6个州和湟源县;鼠疫菌DFR基因型以5、8型为主。其中5型占44．54％（53／119）,分布于都兰、湟源、玉树、杂多、治多、称多、曲麻莱、玛多、囊谦、祁连等地区;8型占32．77％（39／119）,分布于祁连山南北麓、青海湖环湖地区。2004年囊谦县肺鼠疫暴发分离株均为10型;2009年兴海县肺鼠疫暴发分离株（来自鼠疫患者、人尸和牧犬体内）的基因型均为8型。结论　本次试验菌株均具备青藏高原鼠疫病原体特性。菌株溯源分析显示,基于DFR的鼠疫菌基因分型与流行病学调查一致,可用于确定传染源。     

2012年上海市虹口区麻疹流行株基因特征分析

目的 鉴定2012年上海市虹口区麻疹流行株基因型,了解2000--2012年上海市麻疹流行株基因特性。方法 采集疑似麻疹病例咽拭子标本,使用Vero-SLAM细胞分离麻疹病毒,使用RT-PCR扩增分离培养阳性病毒N基因羧基末端450bp片段并测序,与GenBank中的部分流行株构建系统进化树,分析麻疹病毒基因型,同时进行流行病学调查。结果 34份咽拭子标本中分离到麻疹病毒7株,进化树分析显示,6株为Hl基因型,1株为D8基因型。流行病学调查显示,D8基因型为上海自2000年开展病毒监测以来的首次外来输入病毒。结论 2012年虹口区麻疹分离株与历年上海市麻疹流行株属于同一基因型,Hla亚型为优势流行株,首次出现D8基因型,为外来输入病毒。     

青海高原藏系绵羊鼠疫流行病学和病原学特征分析

目的 分析青海高原藏系绵羊鼠疫流行病学和病原学特征。方法 汇总1975－2009年青海省藏系绵羊鼠疫背景资料,分析其地区、时间和人间分布及感染途径和传播的生态学因素,并对藏系绵羊鼠疫分离的14株菌进行生化试验、毒力测定、毒力因子鉴定、质粒分析、差异片段(DFR)分型等研究。结果 1975－2009年从青海省藏系绵羊体内分离的鼠疫菌共14株。由藏系绵羊作为传染源引起人间鼠疫10起,鼠疫病例25例,死亡13例。首发病例均有剥食鼠疫病死藏羊史,其次为接触鼠疫病例而感染;以腺鼠疫为首发病例,由腺鼠疫继发为肺鼠疫、败血型鼠疫病例多且病死率高。藏系绵羊动物鼠疫及人间鼠疫几乎均发生于甘南生态区,与其独特的生态地理景观密切相关。藏羊动物鼠疫与藏羊引发的人间鼠疫几乎一致,其中11月(旱獭入蛰后)从藏羊体内分离的鼠疫菌株数及藏羊作为传染源引发的人间鼠疫病例数最多,构成了青海高原藏羊鼠疫流行时间明显滞后于旱獭鼠疫的特点。分离的14株鼠疫菌均为青藏高原型,其毒力因子及毒力检测均显示为强毒菌。鼠疫菌基因型DFR分析显示,玉树、治多县分离的菌株均为5型,囊谦县分离的2株菌分别为5型和7型,德令哈市分离的菌株为8型。结论 藏系绵羊可感染鼠疫并作为传染源引发人间鼠疫,分离的菌株均具备青藏高原鼠疫病原体特性,并具有青海鼠疫流行演变新特点。     

云南省鼠疫菌Fse I酶切分型及其流行病学意义

目的　构建云南省鼠疫菌Fse I酶切的脉冲场凝胶电泳（PFGE）图谱库并探讨其流行病学意义。方法　采用限制性内切酶Fse I对云南家、野鼠型及丽江玉龙鼠疫菌株进行酶切分析,并聚类分析电泳图谱。结果　30株被试菌株分为16种PFGE型别,其相似性系数为79．8％～100．0％;16种PFGE基因型可以分为4个簇,除EV76自成一簇,其余3个簇分别为家鼠型基因簇、野鼠型基因簇及玉龙基因簇。结论　云南省鼠疫菌PFOE基因型与生态型、生物型相吻合,具有一定的区域聚集性,而丽江玉龙鼠疫菌为一个独立基因簇。     

云南省鹤庆县2017年分离鼠疫菌分子溯源

目的 了解2017年云南省鹤庆县新分离的鼠疫菌的基因分型,为该地的鼠疫防控提供科学依据。方法 采用差异片段（DFR）、规律成簇的间隔短回文重复序列（CRISPRs）和多位点可变数目串联重复序列分析（MLVA）3种方法对10株鹤庆县新分离鼠疫菌进行分型,并将10株鼠疫菌及邻近疫源地鼠疫菌株93株纳入聚类分析。结果 鹤庆鼠疫菌株与丽江鼠疫疫源地菌株具有相同的DFR型（Genomovar 05型）及CRISPRs型（Ca7簇,22型）,在MLVA聚类分析中,鹤庆鼠疫菌株与丽江野鼠鼠疫菌株位于同一个簇,两者之间仅有2个位点（N2117,M23）的差异。结论 2017年云南省鹤庆鼠疫菌株与丽江野鼠鼠疫疫源地菌株具有很高的同源性,鹤庆县疫情可能是丽江鼠疫进一步向南扩散的结果。     

内蒙古自治区乌兰察布市羊种布鲁氏菌HOOF基因分型特征

目的 调查2012-2015年内蒙古自治区乌兰察布市83株布鲁氏菌HOOF分型特征。方法 对临床分离的83株布鲁氏菌采用常规方法和AMOS-PCR进行鉴定;利用8个数目可变串联重复序列 位点的HOOF分型方法对菌株进行基因分型,并用Hunter-Gaston 分辨指数评估各VNTR 位点的多态性和对菌株的综合辨别能力,采用BioNumerics 5.0软件聚类分析和构建聚类图。结果 83株试验菌全部为羊种布鲁氏菌,全部8个分型位点具有极高的多态性,多态性指数为0.998;其中6个位点（1、2、4~7）的多态性指数 ≥ 0.678,其分辨力主要来自多态性指数较高的位点。83株羊种布鲁氏菌聚为8大类76个基因型。6个共享基因型包括13株布鲁氏菌,提示感染患者具有流行病学相关性;另70株菌呈现独特的基因型,提示病原分离自无流行病学相关的散发患者。结论 乌兰察布市人布鲁氏菌病流行以散发和局部暴发共存,且散发为主,而交叉感染患者与传染源转移有关。     

甘肃省鼠疫耶尔森菌规律成簇间隔短回文重复序列位点多态性分析及地区分布

目的 研究甘肃省鼠疫耶尔森菌（鼠疫菌）的规律成簇的间隔短回文重复序列（CRISPR）位点多态性及地区分布。方法 选取1962－2014年分离的203株鼠疫菌,培养并提取DNA。采用3对CRISPR引物对菌株DNA进行PCR扩增,对PCR产物进行测序。根据菌株CRISPR位点的间区序列种类和排列情况,确定菌株的基因型（类群）,采用BioNumerics 5.10软件进行聚类分析。结果 203株鼠疫菌发现有16种间区序列,包括YPa位点9种、YPb位点4种、YPc位点3种,发现新的间区序列a1''。共发现5个CRISPR基因簇,分别为Cb2、Ca7、Ca7''、CaΔ5''、Ca35''。不同的基因簇呈现区域性特征：Cb2主要分布在会宁县、平川区,Ca7主要分布阿克塞哈萨克族自治县;Ca7''主要分布在夏河县;Ca35''主要分布肃北蒙古族自治县、玉门市;CaΔ5''主要集中在肃南裕固族自治县。结论 CRISPR分子分型方法能够较好地区分甘肃省不同疫源地的菌株,且各基因簇呈现一定的区域性特征。对研究甘肃省鼠疫菌进化规律和人间疫情分子生物学溯源有一定意义。     

中国鼠疫耶尔森菌差异区段分型及其地理分布特征

目的 研究中国鼠疫耶尔森菌差异区段（DFR）分型及地理分布特征。方法 对分离自中国11个疫源地3 044株鼠疫菌,应用23个DFR和质粒验证（PMT1）PCR扩增,进行鼠疫菌DFR基因组分型及地理分布特征分析。结果 3 044株鼠疫菌共包括52个基因组型,其中19个为主要基因组型、33个为次要基因组型。在以往鉴定的31个基因组型基础上又增加了 21个新基因组型。其中增加的3个新基因组型均为主要基因组型,即青藏高原喜马拉雅旱獭鼠疫自然疫源地新增加32型、44型,内蒙古高原长爪沙鼠鼠疫自然疫源地新增加50型。结论 在新增加的 21个新基因组型中有3个为主要基因组型,中国鼠疫菌DFR主要基因组型具有明显的地理分布特征。     

中国丙型肝炎病毒基因型分布

目的分析中国丙型肝炎病毒(HCV)基因型的分布及变化趋势。方法计算机检索1994年以来中国医院知识库(CHKD),1998年以来万方数据资源系统、中国生物医学文献数据库(CBMDisc)以及PubMed数据库,并结合文献追溯方法,收集国内HCV基因分型的相关文献。相同HCV亚型分别按地区、研究时间、人群分组,并进行简单数量合并,计算百分比。结果共纳人文献140篇(共168条记录)。不同地区HCV基因型存在差异,其中北方地区基因型较单一,以1b和2a型为主;南方地区HCV基因型种类较多,以1b型为主,2a,3a,3b及6a型各自占较大比例。早期HCV基因型较单一,随着时间推移,1b及2a亚型逐渐减少,而3a,3b及6a亚型逐年增加,亚型类型逐年增多。有偿献血人群lb,2a亚型所占比例较高;吸毒人群HCV基因亚型较多,3型(3a,3b亚型)及6a亚型所占比例较大,且有逐渐向普通人群扩散趋势。结论中国流行最广泛的HCV基因亚型为1b及2a,且分布地区差异较大,并随时间的推移,基因型分布产生较大变化。     

鼠疫耶尔森菌和假结核耶尔森菌基因鉴别方法的建立及评价

目的 建立鼠疫耶尔森菌和假结核耶尔森菌基因鉴别方法。方法 依据鼠疫菌、假结核菌特有的基因组序列["疫岛(PeI)"和"假岛(PsI)"], 与已公布的12株鼠疫菌和4株假结核菌全基因序列进行比对, 设计特异性的引物, 对鼠疫菌、假结核菌和其他肠道细菌进行鉴定。结果 用52株鼠疫菌、57株假结核菌和其他肠道菌株进行验证, 结果显示, 5对鼠疫菌的鉴定引物中, 2对(PeI2和PeI11)仅在52株鼠疫菌中扩出目的条带, 另3对引物(PeI1、PeI3和PeI12)除鼠疫菌外在部分假结核菌株中也扩出目的条带;5对假结核菌鉴定引物中, 1对引物(PsI1)在52株鼠疫菌和57株假结核菌株中扩出目的条带, 4对引物(PsI7、PsI16、PsI18和 PsI19)仅在57株假结核菌株中均扩出目的条带, 在鼠疫菌中未扩出目的条带。结论 用鼠疫菌和假结核菌共有的PsI1序列、鼠疫菌特有的PeI2和PeI11序列及假结核菌特有的PsI7、PsI16、PsI18和 PsI19序列组成的基因鉴别方法, 可以用于鼠疫菌和假结核菌的基因快速鉴别。     

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.