粪便中华支睾吸虫虫卵DNA的提取及PCR检测方法的优化

华支睾吸虫病又称肝吸虫病,是由华支睾吸虫寄生在人或多种动物胆管内所引起的一种人兽共患病.目前,华支睾吸虫的分离鉴定主要集中在成虫或囊蚴,对虫卵的研究甚少.采用分子生物学方法成功建立了感染人粪便中华支睾吸虫虫卵DNA的提取方法及华支睾吸虫基因片段PCR检测方法,同时对PCR反应条件进行优化,为从分子水平上检测华支睾吸虫虫卵提供科学依据.     

华支睾吸虫吉林分离株的鉴定

为了研究吉林省内华支幸吸虫自然分离株的种类及基因变异情况,将镜检含有疑似华支睾吸虫囊蚴的麦穗鱼,经胃蛋白酶消化后获得该寄生虫囊蚴,用比重沉降法去除杂质,同时利用形态学和PCR方法进行种类鉴定.镜检结果表明分离株具有典型的华支睾吸虫囊蚴特征,并且经过PcR方法扩增出了华支睾吸虫的种特异性基因片段,碱基序列与GenBank...     

猪囊尾蚴和华支睾吸虫液相基因芯片检测方法的建立

为建立一种可以同时检测猪囊尾蚴和华支睾吸虫的液相基因芯片方法,本研究以猪囊尾蚴ITS基因和华支睾吸虫ITS基因为靶序列,设计并合成特异性探针和引物,通过PCR方法扩增目的片段,构建阳性重组质粒标准品并对其进行测序,建立一种基于双重PCR的液相基因芯片检测方法。结果显示,扩增目的片段长度分别约为150 bp和170 bp,测序结果与Gen Bank登录的猪囊尾蚴和华支睾吸虫相关基因一致性分别为99.35%和98.27%;液相基因芯片对单重PCR产物和双重PCR产物的检测结果一致,特异性和重复性良好。应用该方法检测猪囊尾蚴和华支睾吸虫的灵敏度分别为5.13×104拷贝/μL和2.03×104拷贝/μL,比琼脂糖凝胶电泳灵敏高约8倍;应用该方法检测猪囊尾蚴和华支睾吸虫的变异系数均在8%以内,模拟污染样品的检验试验准确率达98%。本研究初步建立了可以同时高效、灵敏和特异检测猪囊尾蚴和华支睾吸虫的液相基因芯片方法,为人畜共患寄生虫的检测和监控提供了新方法。     

引起猪贫血的寄生虫病的诊断

1华支睾吸虫病 华支睾吸虫病是由华支睾吸虫寄生于胆道所引起的以肝胆病变为主的人畜共患寄生虫病。华支睾吸虫是寄生在动物胆管和胆囊内的吸虫。本病是人畜共患病。华支睾吸虫的中间宿主是淡水螺,第二中间宿主为淡水鱼或淡水虾。因虫体对胆管的机械性损伤和阻塞作用,虫体分泌物刺激作用下引起胆管及周围组织炎症,导致肝萎缩、肝硬变,肝功能受损,严重者可发生肝癌和胰腺炎。     

华支睾吸虫成虫cDNA表达文库的构建与筛选

为了获得华支睾吸虫成虫期强反应原性抗原基因,首先利用λZAP栽体构建华支睾吸虫成虫cDNA表达文库:即从我国东北疫区(镇赉县)家犬胆管内分离收集华支睾吸虫成虫,采用Trizol Reagent提取其总RNA,Oligo(dT)纤维素柱纯化mRNA,反转录合成第1链cDNA及第2链cDNA,用CHROMA SPIN-400柱离心层析纯化后,与栽体λZAP Express连接,体外包装后成功获得我国东北疫区华支睾吸虫成虫cDNA表达文库.文库容量为1.5×106pfu,重组率为99%,插入片段长度在0.4～2.0 kb之阀,扩增文库的滴度为1.5×1010pfu/mL.然后利用免疫学方法对该cDNA表达文库进行筛选:以自然感染华支睾吸虫的人血清为抗体探针,从2.0×105个重组噬菌体筛选强反应原性抗原基因,对筛选出的强反应原性克隆进行测序,利用相关分子生物学软件进行序列分析.共获得41个阳性克隆,测序结果分析表明,这些cDNAs根据其编码的蛋白可分为以下几种,即与来自华支睾吸虫的甘氨酸-2、脯氨酸-2及Cs44抗原高同源的基因及分别与来自Nematostella vectensis的未知蛋白、转录延伸因子及果蝇CG3446基因编码蛋白较低同源性的基因.本研究结果为进一步对华支睾吸虫抗原的生物学特性研究及应用奠定了理论基础和实验依据.     

华支睾吸虫病在我国的流行及诊断方法研究进展

华支睾吸虫病是由华支睾吸虫引起的危害严重的鱼源性人兽共患寄生虫病,主要引起人和多种动物的肝胆病变,严重者可引起胆管上皮癌,因此华支睾吸虫被国际癌症署(IARC)归为第Ⅰ类生物性致癌因子。我国华支睾吸虫病主要流行于淡水资源丰富的地区,在我国27个省、市、自治区均有该病人体感染的报道。近年来,我国华支睾吸虫感染率呈上升趋势,且受威胁地区和人数不断增加。对该病的诊断和防控已刻不容缓,传统的病原学诊断方法存在着一定的局限性和弊端。免疫学方法和分子生物学技术的不断发展为该病的诊断提供了新的途径,今后在华支睾吸虫病的基础研究与防控中起到更加重要的作用。论文就华支睾吸虫病的流行特点及诊断方法研究进展进行综述,以期为华支睾吸虫病的研究提供参考。     

华支睾吸虫病的防控

华支睾吸虫病是由华支睾吸虫寄生于人、犬、猫、猪及其他野生动物的肝脏胆管和胆囊内,可使肝脏肿大并导致其他肝病变,是一种重要的人兽共患吸虫病。对华支睾吸虫的生活史以及该病的流行病学、致病机理及病理变化、诊断方法、防治措施进行介绍,以期为有效防控华支睾吸虫病提供参考。     

华支睾吸虫病的防控

华支睾吸虫病是由华支睾吸虫寄生于人、犬、猫、猪及其他野生动物的肝脏胆管和胆囊内,可使肝脏肿大并导致其他肝病变,是一种重要的人兽共患吸虫病.对华支睾吸虫的生活史以及该病的流行病学、致病机理及病理变化、诊断方法、防治措施进行介绍,以期为有效防控华支睾吸虫病提供参考.     

肇源县淡水鱼华支睾吸虫囊蚴感染情况的调查及分析

为了解肇源县常见淡水鱼华支睾吸虫囊蚴的感染情况,试验采用直接压片法和消化法对肇源县12种常见淡水鱼华支睾吸虫囊蚴感染情况进行了调查。结果表明:在调查的510尾淡水鱼中,检出阳性鱼186条,感染率为36.47%,其中麦穗鱼、柳根鱼和船丁鱼的感染率分别为92.45%(98/106)、78.95%(15/19)和52.00%(13/25),未在鲈塘鳢、黄颡鱼和泥鳅体内检出华支睾吸虫囊蚴;麦穗鱼的感染强度最高,达到88个/g。说明肇源县淡水鱼华支睾吸虫囊蚴感染率高、感染强度大,在该地区生食或吃未煮熟的淡水鱼感染华支睾吸虫的风险较高。     

河南省宠物猫华支睾吸虫和其他肠道寄生虫感染状况分析

旨在了解宠物猫肠道寄生虫(特别是华支睾吸虫)的感染情况并分析其相关影响因素及临床表现，通过离心沉淀法、卢戈氏碘液染色法和饱和蔗糖溶液漂浮法对河南省11个地区898份宠物猫粪便样品进行显微镜检查，结果显示，总感染率为10.58%(95/898)。在95份阳性样本中，优势虫种为球虫(49.47%)和华支睾吸虫(29.47%),其次为钩口线虫(16.84%)、芽囊原虫(7.37%)、贾第虫(3.16%)和蛔虫(3.16%)。总体来看，肠道寄生虫在焦作地区、6月龄及以下、未驱虫、未免疫和出现腹泻症状的宠物猫中检出率更高。除与性别因素无关外(P>0.05),年龄、驱虫情况、免疫情况等因素均显著影响宠物猫华支睾吸虫的感染率，同时发现宠物猫的腹泻情况也与华支睾吸虫的感染率有显著相关性。临床症状分析表明，华支睾吸虫感染的宠物猫比其他寄生虫感染的宠物猫更消瘦(P<0.001)。综上所述，河南省宠物猫主人今后应重视对幼猫的科学饲喂、做好定期免疫和驱虫，以降低肠道寄生虫的危害及人兽共患华支睾吸虫病的传播风险。     

牛蜱龙岩分离株的分子鉴定

为了解福建省龙岩地区牛场体表蜱的种类,试验采集龙岩地区牛体表寄生蜱样本,基于蜱的核糖体rDNA内转录间隔区(internal transcribed spacer,ITS)序列PCR扩增方法进行分子鉴定,获得ITS1和ITS2基因序列,进行blastn相似性搜索,应用MegAlign和MEGA 7.0软件完成同源性分析及种系发育分析。结果表明,该蜱ITS1序列与中国甘肃微小扇头蜱分离株同源性达99.32%(JQ737124.1、JQ737125.1),与中国湖南微小扇头蜱HAI2分离株同源性达99.16%(MK224531.1);ITS2序列与中国河南、南非豪登微小扇头蜱分离株同源性均为100%(KX450287.1、KY457506.1);种系发育分析结果显示,龙岩地区牛体表分离的牛蜱ITS基因序列与扇头蜱属ITS基因序列聚类,与革蜱属和璃眼蜱属处于两个不同的分支。说明福建龙岩牛蜱分离株为微小扇头蜱。     

湖南省猬迭宫绦虫ITS及5.8S rDNA的克隆及序列分析

利用聚合酶链反应(PCR)扩增猬迭宫绦虫rDNA的ITS-1、5.8S及ITS-2片段,将PCR扩增出的片段纯化后克隆至pGEM-T Easy载体,重组质粒通过菌落PCR鉴定后,对阳性菌落进行序列测定并进行序列分析。结果显示,所获得的ITS及5.8S rDNA序列总长存在一定差异,为1 369~1 393 bp,包含部分的18、28S及全部的ITS-1(662~687 bp)5、.8S(138 bp)及ITS-2(457~475 bp)序列。由于猬迭宫绦虫ITS序列种内相对保守,种间差异较大,故可作为种间遗传变异研究的标记。     

犬隐球菌病病原分离与ITS区序列分析鉴定

为确定引起格力犬皮肤病发生的病原菌种属并提供科学的诊治方案,从病犬发病部位真皮层刮取病料,采用沙氏培养基对病料进行分离、培养,根据菌落形态特征与镜检结果对分离到的病原菌进行初步鉴定。采用真菌鉴定通用引物ITS1及ITS4对分离菌的ITS区序列进行PCR扩增、测序,将测序结果与GenBank中的新生隐球菌进行比对分析并构建系统发育树。结果表明,分离到的病原菌经形态学鉴定初步判定为隐球菌属真菌,其ITS区序列与GenBank中的新生隐球菌（JN939462.1和JN939461.1）的ITS序列相似性为99%,且在系统发育树上属同一分支,提示引起该犬隐球菌病的病原菌为隐球菌属新生隐球菌。     

宁夏苦马豆内生真菌的分离与鉴定

为研究苦马豆（Swainsona salsula）中内生真菌的种属分类,对采自宁夏的苦马豆内生真菌进行分离培养和形态观察,对分离菌株的ITS序列进行扩增、测序和系统发育分析。从宁夏苦马豆植株的叶和茎中共分离出4个真菌菌株,编号分别为SS_NXB1、SS_NXF1、SS_NXG2、SS_NXA1,因植株未表现出任何病害症状,故确定其为内生真菌。根据形态特征和ITS序列,确定前3株真菌为枝顶孢属（Acremonium）真菌。因菌株SS_NXA1未产生分生孢子及GenBank数据库中缺少同源菌株的分类信息而未确定其分类地位。     

Genotypic characterisation of Indian cattle, buffalo and sheep isolates of Echinococcus granulosus

Twelve isolates of Echinococcus granulosus, collected from domestic animals, including cattle, buffalo and sheep were analysed for DNA nucleotide sequence variation within mitochondrial cytochrome c oxidase I (coxI), NADH dehydrogenase subunit I (nadI) and internal transcribed spacer gene I (ITS1). After analysis of sequence information this was found that the fragment size of ITS1 of buffalo isolate was more in comparison to cattle and sheep isolates. Based on the nadI genotype this was found that Indian cattle, buffalo and sheep isolates could be grouped into E. granulosus sensu stricto. Based on coxI genotype two sheep isolates and one buffalo isolate were homologous to G2 genotype. Rests of the isolates were microvariants of G2 genotype. Presence of G2 genotype in buffalo is the first report of this genotype from this host.     

Sequence polymorphism in the ribosomal DNA internal transcribed spacers differs among Theileria species

The genomic region spanning the two ribosomal RNA internal transcribed spacers (ITS1 and ITS2) and the 5.8S rRNA gene was cloned and sequenced from sixteen Theileria isolates. Each Theileria species possessed ITS1 and ITS2 of unique size(s) and species specific nucleotide sequences. Varying degrees of ITS1 and ITS2 intra- and inter-species sequence polymorphism were found among ruminant Theileria species. The spacers were most polymorphic in the agent of tropical theileriosis, Theileria annulata, and were more conserved in two benign species, Theileria buffeli and Theileria sergenti Chitose. Phylogenetic analysis of the rDNA ITS1-5.8S rRNA gene-ITS2 region clearly separated each taxon, placing them in three clusters. One held T. annulata, Theileria parva, and Theileria mutans, with the latter two most closely related. The second held T. sergenti Ikeda, T. sergenti Chitose, and T. buffeli, with the latter two most closely related. The third cluster held the Theileria ovis isolates.     

Transmission trials, ITS2-PCR and RAPD-PCR show identity of Toxocara canis isolates from red fox and dog.

Toxocara canis isolates from dog and from red fox were compared in transmission trials and with molecular analysis using RAPD-PCR technique and comparison of the ITS2 sequence. After oral infection of bitches with 20,000 embryonated T. canis eggs of vulpine and canine origin, the vertical transmission to pup's was examined. All animals of both groups developed typical clinical symptoms of toxocarosis. The haematological, serological, parasitological and post mortem results showed no differences between both isolates except for the infectivity of T. canis stages in mice where the fox isolate showed a significant higher infectivity than the dog isolate. The RAPD-PCR showed a similarity coefficient of 0.95, similar to the range of intraspecific variation in Toxocara cati and Toxascaris leonina specimens as outgroups. The ITS2 comparison showed a 100% identity between both isolates with no intraspecific variations. Therefore, the study shows that the fox and the dog isolate of T. canis were identical in infectivity, transmission and molecular structure; a host adaptation could not be found and the fox has to be seen as a reservoir for T. canis infections in dogs. Considering the increasing number of foxes in urban areas the importance of helminth control in dogs is stressed.     

黄鳝胃瘤线虫ITS及5.8S rDNA的克隆及序列分析

本研究旨在阐明黄鳝胃瘤线虫湖南分离株的核糖体DNA(rDNA)内转录间隔区(ITS)及5.8 S rDNA序列的遗传变异情况,并用ITS序列重构胃瘤线虫与其它线虫的种群遗传关系.利用聚合酶链反应(PCR)扩增胃瘤线虫rDNA的ITS-1、5.8S及ITS-2片段,将PCR扩增出的片段纯化后克隆至pGEM-T Easy载体,重组质粒通过菌落PCR鉴定后,对阳性菌落进行序列测定并进行序列分析.结果显示所获得的胃瘤线虫ITS及5.8 S rDNA序列总长存在一定差异(922～927 bp),其中包含部分的18S、28 S及全部的ITS-1 (350～351 bp)、5.8S(102 bp)及ITS-2 (340～344 bp)序列.本研究系国内首次报道胃瘤线虫的ITS序列,其结果为黄鳝胃瘤线虫的分类鉴定以及进一步的分子流行病学调查和群体遗传研究奠定了基础.     

Morphological and molecular characterisation of Gyrodactylus salmonis (Platyhelminthes, Monogenea) isolates collected in Mexico from rainbow trout (Oncorhynchus mykiss Walbaum)

Gyrodactylus salmonis (Yin et Sproston, 1948) isolates collected from feral rainbow trout, Oncorhynchus mykiss (Walbaum) in Veracruz, southeastern Mexico are described. Morphological and molecular variation of these isolates to G. salmonis collected in Canada and the U.S.A. is characterised. Morphologically, the marginal hook sickles of Mexican isolates of G. salmonis closely resemble those of Canadian specimens - their shaft and hook regions align closely with one another; only features of the sickle base and a prominent bridge to the toe permit their separation. The 18S sequence determined from the Mexican specimens was identical to two variable regions of SSU rDNA obtained from a Canadian population of G. salmonis. Internal transcribed spacer (ITS) regions (spanning ITS1, 5.8S and ITS2) of Mexican isolates of G. salmonis are identical to ITS sequences of an American population of G. salmonis and to Gyrodactylus salvelini Kuusela, Zi?tara et Lumme, 2008 from Finland. Analyses of the ribosomal RNA gene of Mexican isolates of G. salmonis show 98-99% similarity to those of Gyrodactylus gobiensis Gl?ser, 1974, Gyrodactylus salaris Malmberg, 1957, and Gyrodactylus rutilensis Gl?ser, 1974. Mexican and American isolates of G. salmonis are 98% identical, as assessed by sequencing the mitochondrial cox1 gene. Oncorhynchus mykiss is one of the most widely-dispersed fish species in the world and has been shown to be an important vector for parasite/disease transmission. Considering that Mexican isolates of G. salmonis were collected well outside the native distribution range of all salmonid fish, we discuss the possibility that the parasites were translocated with their host through the aquacultural trade. In addition, this study includes a morphological review of Gyrodactylus species collected from rainbow trout and from other salmonid fish of the genus Oncorhynchus which occur throughout North America.     

西北部分地区猪蛔虫rDNAITS基因序列测定及遗传变异分析

为了摸清西北部分地区猪蛔虫内转录间隔区(ITS)的遗传变异特点,扩增了猪蛔虫ITS基因,进行测序,依据GenBank公布的ITS序列将测序结果截为ITS1、5.8S及ITS2三段,分析比对各段序列的差异性。结果显示,所有样品ITS序列长约1 000bp,其中ITS1、5.8S和ITS2的长度分别为450bp~453bp、159bp、272bp,种内差异分别为0~0.2%、0、0。基于ITS1的种系发育分析表明,23个猪蛔虫样品均位于同一分支,而与贝蛔属蛔虫分属两个不同分支。ITS1序列不能作为区分西北不同地区猪蛔虫的种内分子标记,但可以作为区分蛔属蛔虫与贝蛔属蛔虫的种间分子标记,研究结果为猪蛔虫的鉴定和分子流行病学调查提供了基础资料。