蚤、蜱中巴尔通体的分离培养及检测鉴定

目的了解蚤、蜱在我国作为巴尔通体传播媒介的可能性，获得其自然状态下存在于吸血节肢动物中的证据。方法采集家猫、狗、牛及鼠类动物体表寄生蚤、蜱，采用含5％去纤维兔血脑心浸液（brain heart infusion，BHI）培养基置于35℃含5％ CO2培养箱中从蚤、蜱中分离巴尔通体，疑似菌落应用聚合酶链反应技术（Polymerase Chain Reaction，PCR）扩增巴尔通体特异基因片段，阳性产物测序并用同源性比较及系统发育分析等方法分析确定巴尔通体的亲缘关系。结果分别从猫栉首蚤、微小牛蜱中各分离出1株巴尔通体，用5对巴尔通体属特异性引物进行PCR反应，扩增产物均产生阳性目标带，证实为巴尔通体属微生物。序列同源性比较发现蚤、蜱分离株之间同源性较小，tRNA^Ile-tRNA^Ala地基因间隔区序列为58．2％、ftsZ基因序列为72．8％；这两株菌分别与云南鼠类宿主血液中分离的巴尔通体菌株RT222SM、RT221SM同源性最大，与其它已知巴尔通体同源性均较小。蚤培养物与RT222SM的tRNA^Ile-tRNA^Ala基因间隔区的同源性是77．9％、与ftsZ是96．2％；蜱培养物与RT221SM的tRNA^Ile-tRNA^Ala基因间隔区的同源性是99．4％，与云南鼠血中分离的Rf1561yn的gltA基因338bp核酸序列同源性为99．1％，基于gltA种系发育分析提示与Rfl561yn亲缘关系最近。结论从猫栉首蚤、微小牛蜱中分离培养出巴尔通体，为蚤、蜱作为巴尔通体传播媒介提供了线索，同时为在我国进一步开展媒介生物中巴尔通体感染情况调查提供了实验方法的参考依据。同源性搜索、比较及系统发育分析支持这2株巴尔通体与中国云南分离的巴尔通体基因型相似，而与国外的巴尔通体分离株亲缘关系较远。     

应用rLF检测人群血清抗炭疽抗体水平的初步评价

目的对重组炭疽致死因子（rLF）在人群血清抗体水平检测中的初步应用进行评价。方法间接ELISA方法检测人群血清特异抗体,检测结果按照抗体相对含量进行分类比较、t检验、S/N比值大于等于2.1的阳性判断标准等多种方法进行统计分析。结果rLF的检测结果能区别大部分的病人和健康人,实验结果还显示出在我国部分地区的健康人尤其是健康从业人员中也有相当一部分人抗体水平较高,有的甚至达到了感染病人的抗体水平,提示炭疽在我国部分地区有较强隐性感染。结论致死因子显示出一定的应用潜力,可能用在炭疽的临床诊断、疾病监测、以及用来评估某地区的炭疽流行强度。     

云南玉龙及古城区鼠疫自然疫源地判定及初步研究

目的确定云南玉龙县及古城区鼠疫自然疫源地的存在,提出防控策略。方法采用常规调查方法,通过血清学、细菌学、基因诊断等技术进行判定。结果共分离到5株鼠疫杆菌,均酵解甘油、麦芽糖、阿胶糖,不酵解鼠李糖、密二糖,脱氮试验阳性。均带有Pgm 、PstI 、FI 、Vwa 等毒力决定因子;疫区犬血清阳性率为23.5%;猫血清阳性率为26.7%。结论细菌学证实玉龙县为鼠疫自然疫源地,目前鼠疫流行处于活跃期;血清学证实古城区为新的鼠疫疫源区(县);阳性血清动物分布面积210km2,并有进一步扩散趋势;齐氏姬鼠及大绒鼠是本地区优势鼠种,玉龙绒鼠有局部分布。特新蚤指明亚种,方叶栉眼蚤为优势蚤种;分离的鼠疫菌与滇西纵谷型及滇闽居民区型菌株生化特性不同,与西藏北部青藏高原型鼠疫菌的生化特性接近。     

云南省鼠疫疫源地鼠疫菌质粒DNA种类及分子流行病学研究

用琼脂糖凝胶电泳技术，检查了分离自云南省的８２８株鼠疫菌质粒ＤＮＡ特征。结果表明，云南鼠疫菌可观察到分子量为３．９３、６．０５、２２．９７、３５．６５、４５．３５、６４．８２、７４．５９、１１１．３６和１２９．５５Ｍｄａｌ九种质粒，按质粒组成可划分为Ⅰ～Ⅹ种质粒图谱。被检菌株中，９９．１５％具有６．０５、４５．３５和６４．８２Ｍｄａｌ三种规范化质粒，还发现２１．６２％、４．５９％、１．４５％和３．５％的菌株分别尚存３．９３、２２．９７、３５．６５和１１１．３６Ｍｄａｌ质粒，这些质粒有特定的分布区域，具有重要的分子流行病学意义。根据质粒图谱，可将我省鼠疫现有疫区初步划分成滇西北山地、保山盆地、大盈江、陇川江、南定河、澜沧江下游和红河元江段流域七大相对独立的疫源区。本研究的结果结合既往流行病学资料，似可说明：①质粒组成可作为云南省鼠疫疫源地中疫源地划分的重要指标；②云南家、野鼠两型疫源地菌株具有共同的遗传变异性；③近几年之间鼠疫有复燃也存在异地传播；④云南西南部存在鼠疫疫源。     

4种病原菌特异基因片段阳性蜱的16S rRNA基因克隆文库分析

Objective To develop the method of 16S rRNA gene clone library for tick bacterial flora analysis, and to analyze the detection effective of pathogens in tick and capacity of bacterial flora diversity. Methods Primers were designed according to the specific gene of Borrelia burgdorferi, Bartonella henselae, Anaplasma phagocytophilum, Ehrlichia chaffeensis and templates were choosen by positive PCR result to amplify the DNA extracted from the ticks. One set of primers targeting 16S rRNA gene conserved region were chosen to amplify certain fragments, DNA extraction, PCR reaction, cloning and sequencing. Nucleotide sequences were compared with GenBank database. Calculated Coverage values of clone library and Shannon-Wiener diversity index. Results Sixteen defined genus-or species-bacteria were detected in 103 valid sequences. Eight species were edge type (Clone No. > 5). Three kinds of pathogens were identified (Borrelia burgdorferi, Bartonella henselae and Rickettsia sp). Three kinds of pathogens were not edge type(Clone No. < 5). Coverage value was 96.11%, and Shannon-Wiener index was 2.40. Analysis results of cloning sequence showed that tick-parasitic bacteria mainly were α and γ deformation mycetes which accounted for 56.25% (9/16). Conclusions The 16S rRNA gene sequences technology could make relative quantitative of bacterial flora, and detect many kinds of pathogens in tick. It's a good method for detection of pathogens and bacterial flora analysis.     

4种病原菌特异基因片段阳性蜱的16S rRNA基因克隆文库分析

Objective To develop the method of 16S rRNA gene clone library for tick bacterial flora analysis, and to analyze the detection effective of pathogens in tick and capacity of bacterial flora diversity. Methods Primers were designed according to the specific gene of Borrelia burgdorferi, Bartonella henselae, Anaplasma phagocytophilum, Ehrlichia chaffeensis and templates were choosen by positive PCR result to amplify the DNA extracted from the ticks. One set of primers targeting 16S rRNA gene conserved region were chosen to amplify certain fragments, DNA extraction, PCR reaction, cloning and sequencing. Nucleotide sequences were compared with GenBank database. Calculated Coverage values of clone library and Shannon-Wiener diversity index. Results Sixteen defined genus-or species-bacteria were detected in 103 valid sequences. Eight species were edge type (Clone No. > 5). Three kinds of pathogens were identified (Borrelia burgdorferi, Bartonella henselae and Rickettsia sp). Three kinds of pathogens were not edge type(Clone No. < 5). Coverage value was 96.11%, and Shannon-Wiener index was 2.40. Analysis results of cloning sequence showed that tick-parasitic bacteria mainly were α and γ deformation mycetes which accounted for 56.25% (9/16). Conclusions The 16S rRNA gene sequences technology could make relative quantitative of bacterial flora, and detect many kinds of pathogens in tick. It's a good method for detection of pathogens and bacterial flora analysis.     

我国新发现的鼠疫自然疫源地鼠疫菌基因组序列测定及分析

目的 测定和分析我国新发现的鼠疫自然疫源地鼠疫菌株（耶尔森菌）的全基因组序列,探讨玉龙疫情菌株(D106004)与邻近两个疫源地剑川菌株(D182038)和西藏菌株(Z176003)的亲缘关系。方法 采用全基因鸟枪法及Solexa方法对3株鼠疫菌株进行全基因组测序,并进行比较基因组学分析。基因组间编码序列比较分析采用BLAST软件进行,基因组间重排分析采用MAUVE软件进行。结果 鼠疫菌株D106004、D 182038、Z176003均具有1个染色体和3个质粒,菌株间染色体、质粒特征基本相似;3株菌株间编码序列的蛋白相邻类的聚簇(COG)功能分类及插入序列数目比较差异无统计学意义(x2值分别为3.03、0.257,P均＞0.05)。菌株间编码序列、单核苷酸多态性(SNPs)和基因组重排结果显示,在3株菌株中,有2882个基因具有100％的同源性。其中D106004菌株预测的3636个基因中与D182038菌株一致的基因有2994个,90％以上相似的基因有240个;与Z176003菌株一致的基因有3113个,90％以上相似的基因有200个;D106004菌株与Z176003、D182038菌株的同义SNPs数为59、68个,非同义SNPs数为104、203个;D106004与Z176003菌株之间可分为11个重排片段,较之D106004与D182038菌株之间的16个重排片段数目明显减少。结论 3株鼠疫菌株基因之间具有高度同源性,D106004与Z176003菌株之间的亲缘关系较之与D182038菌株更为接近,玉龙疫源地菌株可能是由西藏疫源地菌株进化而来。     

脂质体用于鼠疫免疫的研究——Ⅰ 脂质体包鼠疫菌F1抗原免疫家兔、小鼠的抗体增强作用

本文应用脂质体包被鼠疫菌 F_1抗原及其结合物免疫家兔及小鼠观察其免疫增强作用,通过对照组比较其作用得到确认     

鼠疫菌特异基因的克隆表达和抗原性分析

目的 在大肠埃希菌中克隆表达鼠疫菌特异基因(YPO1089.pst、ymt),分析重组蛋白的抗原性.方法 利用PCR技术扩增目的 基因,PCR产物经纯化、双酶切后,与质粒载体pET-30a(+)相连接并转化大肠埃希菌BL21(DE3)感受态细胞.经异丙基硫代-β-D-半乳糖苷(IPTG)诱导表达目标蛋白,并进行10%的变性聚丙烯酰胺凝胶电泳,蛋白免疫印迹分析其特异性,最后采用亲和层析法纯化诱导表达的融合蛋白.结果 成功构建了pET-YPO1089、pET-pst和pET-ymt 3个重组表达质粒,经优化诱导表达条件,重组的rYP01089、rPst和rYmt在大肠埃希菌中均得到了稳定高效地表达;免疫印迹结果表明重组的rPst可与鼠疫阳性血清发生特异性的免疫反应;目标蛋白经纯化后纯度可达95%以上.结论 鼠疫菌的特异性抗原能够在原核蛋白表达系统中获得高效表达,rPst具有敏感且特异的免疫学特性,实验结果为开发新型鼠疫诊断试剂奠定了基础.     

鼠疫菌毒力基因研究进展

鼠疫菌毒力基因研究进展俞东征（中国预防医学科学院流行病学微生物学研究所，北京市１０２２０６）１Ｆ１抗原及其基因表达在鼠疫耶尔森氏菌的抗原中，Ｆ１抗原具有极为重要的意义，它不仅是鼠疫菌中最早发现的抗原，也是最主要的保护性抗原，而且它对于鼠疫菌具有非常高...