天山山地灰旱獭-长尾黄鼠鼠疫疫源地鼠疫菌基因分型研究

目的对天山山地灰旱獭．长尾黄鼠鼠疫疫源地鼠疫菌进行基因分型。方法根据已经证实的22个差异区段（DFR）设计引物，对每株鼠疫菌进行PCR扩增。结果61株天山疫源地鼠疫菌株共包括4个基因型，即1、2、3、4型。基因型1、2和3在北天山疫源地西部鼠疫菌株中都有分布，但尼勒克菌株的基因型全部为1型。南天山疫源地阿合奇和阿图什两个县菌株的基因型存在显著差别，阿合奇菌株基因型与北天山疫源地的菌株比较接近，而3株阿图什菌株的基因型均为4型，与帕米尔高原长尾旱獭鼠疫疫源地鼠疫菌株相同。结论基因分型结果与纪树立的生态分型基本一致。天山疫源地和帕米尔高原疫源地在阿图什县有交叉。     

44株中国田鼠型与24株非田鼠型鼠疫菌的DFR检测分析

目的比较我国两个田鼠鼠疫自然疫源地的44株田鼠型鼠疫菌的基因组组成，研究中国田鼠型鼠疫菌的遗传稳定性。方法根据已经证实的22个差异区段(I)FR)设计引物，每株鼠疫菌的每个DFR都采用PCR技术进行验证。结果22个DFR在两种田鼠型鼠疫菌的分布状态完全一致，即均同时缺失了DFR6、DFR11、DFR12、DFR13、DFR18、DFR19和DFR20，与来源于其他鼠疫自然疫源地非田鼠型鼠疫菌的基因组成有显著差别。结论锡林郭勒高原型鼠疫菌和青藏高原青海田鼠型鼠疫菌在基因组组成上高度一致，田鼠型鼠疫菌的基因缺失可能与其对人不致病有关。     

松辽平原达乌尔黄鼠鼠疫自然疫源地鼠疫茵基因分型

为了研究松辽平原达乌尔黄鼠鼠疫自然疫源地鼠疫耶尔森菌（以下简称鼠疫菌）的基因组成，采用PCR技术对分离自该疫源地88株鼠疫菌进行了基因分型，其中黑龙江4株、吉林43株、辽宁4株、内蒙37株，鼠疫菌DNA均由青海省地方病预防控制所鼠疫菌专业实验室提供。     

新疆山地鼠疫自然疫源地鼠疫耶尔森菌基因组分化和演变

目的比较来自我国新疆4大片山地鼠疫自然疫源地的144株鼠疫菌的基因组组成的差别,研究新疆山地鼠疫自然疫源地鼠疫菌的基因分型和进化规律。方法根据已经证实的22个差异区段(DFR)设计引物,每株鼠疫菌的每个DFR都采用PCR技术进行验证。结果新疆4大片山地鼠疫自然疫源地的144株鼠疫菌的基因型DFR图谱可归类为14种,分为7个主要基因组型和7个次要基因组型。西天山北坡灰旱獭-长尾黄鼠鼠疫疫源地存在3个主要基因组型和5个次要基因组型,西段以01型基因组型为主,占种群体的91.7%,02型占8.3%;中段以03型为主,占68.8%,01型占4.2%,02型占20.85%,另有02M1和02M3(02型的突变型)占2.1%,03M1型(03型的突变型)占2.1%;东段以02型为主,89.8%,01型、02M2、02M3和02M4型(02型的突变型)各占2.0%。南天山灰旱獭鼠疫疫源地存在2个主要基因型和1个次要基因型,以4型为主,占66.7%,02型占16.7%, 04M1型(04型的突变型)占16.7%。帕米尔高原-阿赖山红旱獭鼠疫疫源地仅存在04型1种基因型。昆仑山喜马拉雅旱獭鼠疫疫源地分为中昆仑和东昆仑鼠疫自然疫源地,中昆仑山存在2种鼠疫基因组型,以11型为主,占群体的90%,12型占10%;东昆仑山存在3种鼠疫基因组型,以05型为主,占66.7%,02型和11型分别占16.7%。结论新疆山地鼠疫自然疫源地鼠疫菌基因组的演化由3个演化路线组成。西天山北坡鼠疫自然疫源地的鼠疫菌基因组,自西向东在不同的生态地理环境和宿主媒介作用下发生适应性进化和演变,由较为古老的01型基因组逐渐演化为02和03型,最后南下至青海和东昆仑演变为05型,并且在这条演化路线上存在许多演变过程中发生的基因组地域交叉和次要基因组型;南天山和帕米尔高原-阿赖山鼠疫自然疫源地的鼠疫菌的04型基因组型是由01型直接演化而来,并在这一区域形成主要鼠疫基因组型;中昆仑山鼠疫自然疫源地的鼠疫菌基因组型可能是由西藏冈底斯山喜马拉雅旱獭鼠疫源地的鼠疫菌的10型基因组演化而来,形成以11型为主,12型为辅的鼠疫基因组构型特点。     

松辽平原达乌尔黄鼠鼠疫自然疫源地鼠疫菌基因分型

为了研究松辽平原达乌尔黄鼠鼠疫自然疫源地鼠疫耶尔森菌(以下简称鼠疫菌)的基因组成,采用PCR技术对分离自该疫源地88株鼠疫菌进行了基因分型,其中黑龙江4株、吉林43株、辽宁4株、内蒙37株,鼠疫菌DNA均由青海省地方病预防控制所鼠疫菌专业实验室提供。引物设计和PCR扩增方法:在周冬生等鉴定的22个差异区段(DFR)中,有3个位于pMT1质粒中,19个位于染色体上。采用ArrayDesigner2.0软件针对每个DFR各设计1对引物,为了证实pMT1的存在,我们还特意针对pMT1质粒设计了1对引物,引物序列为5′AACACTA TCTCATTCCGCAGTAAAG3′。PCR…     

准噶尔盆地鼠疫耶尔森菌的基因组型分析

目的 对我国新发现的准噶尔盆地大沙鼠鼠疫自然疫源地的鼠疫菌株进行基因组差异性区段的比较分析,确定该鼠疫疫源地鼠疫菌株的基因组类型.方法 按常规方法提取鼠疫菌染色体DNA,依据已证实的鼠疫菌22个差异性区段(DFR)设计引物,采用PCR技术检测鼠疫菌基因组差异性基因片段的构成.结果 准噶尔盆地鼠疫菌株的差异性区段结构类型为缺失DFRO1、04、06、07、10、13和DFR15～18,不同于其他鼠疫疫源地鼠疫菌株的结构类型.为我国新的鼠疫菌基因组型.结论 准噶尔盆地大沙鼠鼠疫疫源地鼠疫菌株的基因组结构类型为我国新的基因组类型.     

应用抑制削减杂交技术进行鼠疫耶尔森菌的比较基因组研究

目的确定古典型鼠疫耶尔森菌的特有序列，为建立和完善该菌基因组分型系统提供可靠数据。方法通过抑制削减杂交技术发现差异片段并应用PCR验证。结果发现了5个在不同生物型鼠疫菌问存在差异的DNA片段，其中一个383bp的片段在来自天山山地灰旱獭、长尾黄鼠鼠疫自然疫源地的30株鼠疫菌全部阳性，而来自其它鼠疫自然疫源地的菌株全部阴性，5株假结核耶尔森菌中有2株(生物Ⅰ型和Ⅱ型)阳性。结论该383bp片段为天山山地灰旱獭、长尾黄鼠鼠疫自然疫源地的鼠疫菌所特有，此疫源地的菌株可能是我国较古老的鼠疫菌。     

云南、福建和贵州省鼠疫耶尔森菌基因分型研究

云南省位于我国西南边陲，存在滇西山地齐氏姬鼠大绒鼠鼠疫自然疫源地（野鼠鼠疫疫源地）和滇西山地闽广沿海居民区黄胸鼠鼠疫自然疫源地（家鼠鼠疫疫源地），除了剑川地区属于野鼠鼠疫疫源地外，云南省的西北部疫区均属于家鼠鼠疫疫源地。福建省位于我国东南沿海，其境内的鼠疫自然疫源地也属于家鼠鼠疫疫源地。贵州省兴义市位于云南和广西省交界处，也属于家鼠鼠疫疫源地。为了比较家鼠及野鼠疫源地鼠疫耶尔森菌（以下简称鼠疫菌）基因组成的差别，采用PCR技术对分离自三省的69株鼠疫菌进行了基因分型研究。     

准噶尔盆地大沙鼠鼠疫自然疫源地鼠疫耶尔森菌质粒谱的研究

目的 了解和掌握准噶尔瓮地大沙鼠鼠疫自然疫源地鼠疫菌质粒谱类型.方法 提取新疆地区不同鼠疫自然疫源地及青藏高原喜玛拉雅旱獭鼠疫自然疫源地、昆仑山喜马拉雅旱獭鼠疫自然疫源地和内蒙古长爪沙鼠鼠疫自然疫源地的39株鼠疫菌质粒DNA,采用琼脂糖凝胶电泳法对其进行质粒谱图型分析.结果 在检测的26株准噶尔盆地大沙鼠鼠疫自然疫源地鼠疫菌中,有23株质粒谱为6×106、45×106、65×106,3株为6×106、45×106和72×106.结论 准噶尔盆地大沙鼠鼠疫自然疫源地鼠疫菌质粒谱分为两个类型:一为6×106、45×106、65×106质粒谱型,是该疫源地的主要质粒谱型,与邻近的北天山灰旱獭.长尾黄鼠鼠疫自然疫源地及内蒙占长爪沙鼠鼠疫自然疫源地、昆仑山喜马拉雅旱獭鼠疫自然疫源地和青藏高原喜马拉雅旱獭鼠疫自然疫源地的鼠疫菌主要质粒谱型一致;二为6×106、45×106和72×106质粒谱型,为少数型,在我国系首次发现.     

西藏地区鼠疫菌生物学特性的分析

目的：通过对西藏地区29个县（市），不同宿主分离的116株鼠疫菌生化，毒力，毒力因子，质粒及外膜蛋白的分析，了解该疫源地内鼠疫病原体间的群落关系及遗传变异的规律性。方法：各项检查均按常规方法进行。结果：目前该地区仅有岗底斯山型和青藏高原型两种生态型菌株，二者分别占据一定的地理区域，以念青唐古拉山脉为天然屏障，从藏北地区分离的菌株为青藏高原型，藏南地区及其西南部所分离的菌株均为岗底斯山型。结论：西藏地区是以喜玛拉雅旱獭为主要宿主的鼠疫自然疫源地，就其鼠疫菌生物学特性分析表明，藏北高原疫源地可能是青藏高原喜玛拉雅旱獭疫源地的延伸，而藏南谷地可能是由于有天然屏障的存在，形成了自己特定的地理环境，从而表现为相对独立的一块鼠疫自然疫源地。     

Genotyping of strains of Yersinia pestis from Marmota baibacina-Spermophilus undulates Plague Focus of Tianshan Mountains in China

Themainreservoirsoftheplaguebaccilusare MarmotabaibacinaandCitellusundulatesin PlagueFocusofTianshanMountainsinChina.BotharepartofRodentiaSciuridae,butdonot belongtothesamegenus(MarmotaandSper mophilusrespectively).Themainvectorsare OropsyllasiantiewiandCallopsylladorablis.Threecounties,Wusu,JingheandNilekein NorthernTianshanMountainsareMarmotabaiba cina SpermophilusundulatesPlagueFocus.Five counties,Changji,HutubiandManasiinEasternTianshanMountainsandAheqiandAtushiin SouthernTia…     

Molecular characterization of Burkholderia cepacia isolates from cystic fibrosis (CF) patients in an Italian CF center

Bacteria of the Burkholderia cepacia complex consist of a number of closely related genomic species (genomovars) potentially pathogenic for cystic fibrosis (CF) patients, collectively referred to as the B. cepacia complex. The genomovar status and epidemiological relatedness of B. cepacia complex strains recovered from CF patients, attending a CF Center at the University Hospital "Policlinico Umberto I" of Rome, were investigated using 16S rRNA PCR-RFLP, recA PCR-RFLP, genomovar-specific PCR, and RAPD. Forty-seven isolates identified as B. cepacia by commercial systems were repeatedly recovered from 19 CF patients. The taxonomy approach used in this study showed that 17 of the 19 patients were colonized by B. cepacia complex strains. Genomovar III (11 strains) was the most prevalent genomovar. Two strains of genomovar I, one B. stabilis (genomovar IV), one B. multivorans (genomovar II), and 4 strains of B. anthina (genomovar VIII) were also identified. This is the first report of multiple patient colonization by B. anthina in a CF center. The epidemiological and genetic relatedness as well as the presence of molecular markers associated with virulence and transmissibility of the B. cepacia complex strains were determined and probable patient-to-patient spread was observed.     

The difference in the lcrV sequences between Y. pestis and Y. pseudotuberculosis and its application for characterization of Y. pseudotuberculosis strains.

We have sequenced the lcrGVH operon from Y. pseudotuberculosis plasmid pYV995 and compared its sequence with that of Y. pestis. The sequences were highly homological, however, six base pair substitutions were found in one short 14 bp region termed variable sequence. Two oligonucleotides corresponding to variable sequence of Y. pestis (pes-V) or Y. pseudotuberculosis (ptb-V) were synthesized and were used as molecular probes in hybridization experiments with sets of Y. pestis and Y. pseudotuberculosis strains. All 17 Y. pestis strains tested were positive only with the pes-V probe, 18 of 21 Y. pseudotuberculosis strains were positive with the ptb-V probe, while three Y. pseudotuberculosis strains reacted with the pes-V probe but not the ptb-V probe. The 200 bp fragment including variable sequence was sequenced in seven Y. pseudotuberculosis strains. The Y. pseudotuberculosis strains which were positive with the pes-V probe possessed the 200 bp fragment sequence almost identical with that from Y. pestis. No correlation between the Y. pestis-like lcrV sequence and virulence was found for these strains. Moreover, the Y. pseudotuberculosis strains with Y. pestis-like sequences in contrast to Y. pestis possessed unaltered yadA gene. However, we have found the yadA frameshift mutation characteristic for Y. pestis in one Y. pseudotuberculosis strain 312.     

Substrains of 129 mice are resistant to Yersinia pestis KIM5: implications for interleukin-10-deficient mice

Interleukin-10 (IL-10)-deficient mice are resistant to several pathogens, including Yersinia pestis. Surprisingly, we observed that heterozygous IL-10(+/-) mice also survive high-dose intravenous infection with Y. pestis KIM5 (Pgm(-)). Analysis of commercial IL-10(-/-) mice revealed that at least 30 cM of genomic DNA from the original 129 strain remains, including a functional Slc11a1 (Nramp1) gene. Interestingly, two substrains of 129 mice were resistant to high-dose Y. pestis KIM5. Resistance does not appear to be recessive, as F(1) mice (C57BL/6J x 129) also survived a high-dose challenge. A QTL-based genetic scan of chromosome 1 with 35 infected F(1) backcrossed mice revealed that resistance to KIM5 maps to a region near IL-10. Two novel IL-10(+/+) mouse strains which each possess most of the original 30-cM stretch of 129 DNA maintained resistance to high-dose infection with Y. pestis KIM5 even in a heterozygous state. Conversely, a novel IL-10(-/-) mouse strain in which most of the 129 DNA has been crossed out exhibited intermediate resistance to KIM5, while the corresponding IL-10(+/-) strain was completely susceptible. Taken together, these results demonstrate that 129-derived genomic DNA near IL-10 confers resistance to Yersinia pestis KIM5 and contributes to the observed resistance of IL-10(-/-) mice.     

我国鼠疫菌质粒种类及组成特征的研究

研究了分离自我国各疫源地的2006株鼠疫菌,共观察到13种质粒,分子量分别为(6、7、13、16、22、23、27、30、45、52、65、73、92)×10~6。不同鼠疫菌株的质粒组成有四种类型;含3种质粒的居多,含4种的次之,为数较少的含2种或5种质粒。由于大质粒分子量的差异以及一些菌株带有附加的质粒或质粒缺失,致使我国鼠疫菌在质粒组成上有16种组合形式,但多数菌株带有分子量为(6、45、65)×10~6的质粒(63.01％)。     

Yersinia pestis--etiologic agent of plague.

Plague is a widespread zoonotic disease that is caused by Yersinia pestis and has had devastating effects on the human population throughout history. Disappearance of the disease is unlikely due to the wide range of mammalian hosts and their attendant fleas. The flea/rodent life cycle of Y. pestis, a gram-negative obligate pathogen, exposes it to very different environmental conditions and has resulted in some novel traits facilitating transmission and infection. Studies characterizing virulence determinants of Y. pestis have identified novel mechanisms for overcoming host defenses. Regulatory systems controlling the expression of some of these virulence factors have proven quite complex. These areas of research have provide new insights into the host-parasite relationship. This review will update our present understanding of the history, etiology, epidemiology, clinical aspects, and public health issues of plague.