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为阐明河南区域隐孢子虫分子流行病学特点,用PCR技术扩增分离虫株的18S rRNA基因全序列和HSP70基因序列,并对扩增片段进行测序。用PAUP 4.0和TREEPUZZLE 4.1构建进化树,试图从分子水平证明河南省不同地区不同宿主来源隐孢子虫的遗传特征,以阐明隐孢子虫病的分子流行病学特点。通过18S rRNA基因全序列和HSP70基因序列分析,其结果：河南人源隐孢子虫分离株为Cryptosporidium parvum鼠基因型;河南鹿源隐孢子虫分离株为C. parvum鹿基因型;河南猪源隐孢子虫的2个分离株均为C. parvum猪基因I型,即C. suis;河南鹌鹑源的隐孢子虫2个分离株分别为C. baileyi和C. meleagridis;河南乌鸡源隐孢子虫和鸵鸟源隐孢子虫分离株均为C. baileyi;河南牛源隐孢子虫分离株为C.andersoni。 相似文献
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基于ITS-1基因序列的隐孢子虫种群分类 总被引：2，自引：0，他引：2
本试验以内转录间隔区1(ITS-1)基因作为研究对象,用PCR技术分别对广东(GD)禽源、广东(GD)和安徽(AH)牛源3个隐孢子虫分离株ITS-1基因进行扩增、克隆、序列测定和分析.将扩增序列用DNAStar(4.0)和ClustalX1.81软件与GenBank上登录的参考序列比对,用Phylip3.67构建种群发育进化树,以确定分离株与其他隐孢子虫虫种之间的亲缘关系.通过对ITS-1基因全序列分析,结果表明:禽源隐孢子虫GD分离株为Cryptosporidium baileyi,牛源隐孢子虫GD分离株和AH分离株均为C.andersoni.因此,ITS-1基因可作为隐孢子虫分离株种群分类的遗传标记,从而为隐孢子虫属的种间鉴定以及进一步的分子流行病学调查和分子诊断学研究奠定了基础. 相似文献
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应用RT-PCR方法对南京、上海和合肥猪源隐孢子虫卵囊SSU rRNA部分序列进行扩增,产物测序后提交GenBank,收录号为DQ855266、DQ855267;用BLAST和DNAStar软件与GenBank参考序列进行比较,分析其同源性,绘制系统发育进化树,结合卵囊形态学观察和对小鼠、大鼠、兔、山羊和鸡的传染性试验确定隐孢子虫种类或基因型。结果表明,3地区猪源隐孢子虫分离株与微小隐孢子虫(C.parvum)同源性达94%~100%,与C.parvummouse型有99.8%~100%的同源性,并处于进化树的同一分支。因此,3地区猪源隐孢子虫是C.parvummouse型,提示猪和鼠之间存在交叉传播的可能。 相似文献
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隐孢子虫不同基因型P23基因的克隆及序列比较 总被引：2，自引：1，他引：1
为克隆隐孢子虫不同基因型子孢子表面抗原P23基因,比较其序列差异,提取上海地区分离的隐孢子虫鼠基因型(Cryptosporidiummouse genotype)、隐孢子虫兔基因型(Cryptosporidiumrabbit geno-type)、隐孢子虫猪基因型Ⅱ(Cryptosporidiumpig genotypeⅡ)总RNA,经RT-PCR扩增P23基因,克隆到pMD18-T载体中,进行序列测定,并与GenBank上下载的微小隐孢子虫(Cryptosporidium parvum)序列进行同源性比对。结果显示,从隐孢子虫3个基因型中均扩增出了P23基因。与微小隐孢子虫P23基因核苷酸序列比较,隐孢子虫鼠基因型、兔基因型、猪基因型ⅡP23基因同源性分别为97.6%、97.3%、97.3%,氨基酸序列同源性分别为97.3%、97.3%和96.4%。获得了隐孢子虫鼠基因型、兔基因型、猪基因型Ⅱ子孢子表面抗原P23基因。 相似文献
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为了解新疆某医院粪便样本中人源性隐孢子虫种系基因型,将收集来的腹泻病人粪便样本采用乙酸乙酯-改良抗酸染色法进行卵囊鉴定,同时提取隐孢子虫感染阳性样本的核酸,设计特异性引物扩增隐孢子虫的18 S rRNA基因和HSP70基因,依据所获得的目的基因序列构建系统发生分析。结果表明,新疆地区人粪便中隐孢子虫的阳性率为16.5%,高于全国平均水平。系统进化分析显示,其分子生物学特征主要为微小隐孢子虫(C.parvum)和人隐孢子虫(C.hominis)。说明新疆地区人源性隐孢子虫种系主要为C.parvum及C.hominis,具备人兽共患传播的可能性。 相似文献
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为克隆不同种隐孢子虫(Cryptosporidium spp.)的半胱氨酸蛋白酶Cryptopain-1基因,分析其核苷酸与编码氨基酸序列的变异情况,根据GenBank上公布的微小隐孢子虫(C.parvum)Cryptopain-1基因序列设计合成引物,用PCR技术从不同种隐孢子虫基因组DNA中扩增Cryptopain-1基因,并将其克隆至pZeroBack/blunt载体,阳性克隆经PCR鉴定正确后测序,与微小隐孢子虫Cryptopain-1基因进行序列同源性比对,并进行系统进化分析。结果显示,本研究成功从泰泽隐孢子虫(C.tyzzeri)、火鸡隐孢子虫(C.meleagridis)、兔隐孢子虫(C.cuniculus)基因组DNA中扩增出Cryptopain-1基因。与微小隐孢子虫Cryptopain-1基因比较,泰泽隐孢子虫、火鸡隐孢子虫、兔隐孢子虫Cryptopain-1基因核苷酸序列相似性分别为98.67%、94.53%、98.34%,演绎的氨基酸序列相似性分别为99.00%、96.51%、99.00%。研究结果为利用Cryptopain-1基因进行隐孢子虫的代谢、致病机理等研究奠定了基础。 相似文献
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《中国兽医学报》2019,(7):1325-1329
本研究从河北省奶牛场有腹泻症状2月龄左右的犊牛粪便中分离卵囊,进行病原分离与虫株鉴定。采集腹泻犊牛的新鲜粪便24份,采用饱和蔗糖溶液漂浮法和抗酸染色法检测隐孢子虫卵囊,观察卵囊形态、大小。提取卵囊基因组DNA,进行18S rRNA基因PCR扩增及琼脂糖凝胶电泳检测。对扩增片段进行序列测定及分析,进一步确定分离虫株隐孢子虫的种类/基因型,根据18S rRNA基因核苷酸序列构建系统发育进化树,确定虫株亲缘关系。结果显示,5份样品检出隐孢子虫卵囊,感染率为20.83%。形态学观察卵囊呈长圆形或椭圆形,大小为(5.0～8.2)μm×(4.2～6.3)μm,平均大小为6.6μm×5.3μm,卵囊指数为1.24,鉴定分离虫株为安氏隐孢子虫。PCR扩增出预期大小为1 188 bp的特异性片段,序列分析和同源性分析结果表明,分离株与安氏隐孢子虫AB089285.2株、AB513856.1株、AY954885.1株的同源性为98.7%～98.8%,进一步表明分离的隐孢子虫虫株为安氏隐孢子虫。在种系进化关系上,分离株与安氏隐孢子虫AB513856.1株亲缘关系最近。本研究为揭示河北省奶牛隐孢子虫病的流行特征,实施有效防制措施提供了科学依据。 相似文献
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安氏隐孢子虫ITS-1序列的PCR扩增、克隆及分析 总被引：1，自引：0，他引：1
通过对国内三株安氏隐孢子虫(Cryptosporidium andersoni)即GD株、HN株和AH株的rDNA的内转录间隔区Ⅰ(ITS_1)序列进行PCR扩增、克隆、测序和序列分析,旨在确定ITS_1是否可作为C.andersoni分子分类的遗传标记。结果表明:GD株、HN株和AH株的ITS_1序列基本一致,仅AH株有三个碱基的差异;但与GenBank注册的C.muris和C.parvum存在种间差异,而且差异显著。说明ITS_1可作为C.andersoni种的遗传标记,从而为隐孢子虫属的种间鉴定以及进一步的分子流行病学调查和分子诊断学研究奠定了基础。 相似文献
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为了解山东省滕州市羊隐孢子虫感染情况和种类,从该市2个绵羊场、2个山羊场采集222份羊粪便样品,提取所有样品的基因组DNA,采用巢式PCR扩增隐孢子虫actin基因,对阳性样品进行序列测定和分析。结果显示,滕州市羊隐孢子虫总的感染率为6.76%,其中绵羊7.84%,山羊5.83%;不同月龄的羊感染情况不同,6~12月龄绵羊感染率最高(20.69%),而12月龄以上的山羊感染率最高(10.00%);共发现3种隐孢子虫感染,其中微小隐孢子虫(Cryptosporidium parvum,C.parvum)检出率最高为53.33%,其次是肖氏隐孢子虫(C.xiaoi)为40.00%,仅发现1例(6.67%)泛在隐孢子虫(C.ubiquitum)感染;序列比对结果显示,本试验所获得基因序列与Gen Bank中的C.parvum、C.xiaoi、C.ubiquitum actin基因序列同源性达到100%;系统进化分析显示,滕州市的羊样品中鉴定的actin序列,与Gen Bank中的相应虫种序列在同一分支上。研究结果为深入了解滕州市羊隐孢子虫流行情况及制定有效的防控措施提供了依据。 相似文献
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山羊脑多头蚴线粒体nad1基因的克隆及序列分析 总被引：1，自引：1，他引：0
本研究旨在阐明脑多头蚴湖南分离株线粒体烟酰胺腺嘌呤二核苷酸(NADH)脱氢酶亚单位1基因(nad1)部分序列(pnad1)的遗传变异情况,并用pnad1序列重构脑多头蚴与其他带科绦虫的种群遗传关系。利用聚合酶链反应(PCR)扩增脑多头蚴的pnad1,应用ClustalX 1.81程序对序列进行比对,再用Phylip3.67程序MP法和Mage4.0程序NJ法绘制种系发育树,并用Puzzle5.2程序构建最大似然树,同时利用DNAStar 5.0中的Megalign程序进行同源性分析。结果显示,所获得的pnad1序列长度分别均为430 bp,湖南分离株与已知多头带绦虫位于同一分枝。由于脑多头蚴pnad1序列种内相对保守,种间差异较大,故均可作为种间遗传变异研究的标记,从而为脑多头蚴的分子流行病学和其相关疾病的诊断奠定基础。 相似文献
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Molecular and morphologic characterization of a Cryptosporidium genotype identified in lemurs 总被引：3，自引：0，他引：3
da Silva AJ Cacciò S Williams C Won KY Nace EK Whittier C Pieniazek NJ Eberhard ML 《Veterinary parasitology》2003,111(4):297-307
This study reports the molecular and morphologic characterization of a Cryptosporidium sp., identified in stools of captive lemurs Propithecus verreauxi coquereli. Stool samples were collected from seven animals (n=7) presenting episodes of diarrhea. Bright-field light microscopy of stool smears stained with modified acid-fast technique revealed the presence of Cryptosporidium sp. oocysts in four of the stool samples analyzed. All microscopically positive samples were confirmed by PCR using primers designed to amplify DNA fragments from two independent loci, i.e. the Cryptosporidium oocyst wall protein (COWP) gene and the small subunit ribosomal RNA (ssrRNA) gene. Phylogenetic analysis based on the full-length ssrRNA gene placed this isolate within a clade that contains all currently known C. parvum species/genotypes, closely related to the C. parvum pig genotype. Comparison with partial ssrRNA sequences available in the GenBank revealed 100% sequence identity with the genotype previously identified in Canadian patients. This finding was confirmed further by comparison of the COWP gene partial sequences. 相似文献
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The purpose of the present study was the genetic characterization, sequencing and phylogenetic analysis of 18S rDNA sequences of Cryptosporidium isolates obtained from different animal hosts in Brazil. Fecal samples containing Cryptosporidium oocysts were obtained from chickens, ducks, quails, guinea pigs, dairy calves, dogs and cats. For amplification of 18S rDNA sequences the Secondary-PCR product of the extracted DNA from fecal suspension of each studied animal was utilized. The primary genetic characterization of Cryptosporidium sp. was performed using RFLP with the enzymes SspI and VspI. DNA samples were sequenced and subjected to phylogenetic analysis. The results showed C. baileyi infecting two ducks and one quail and C. melagridis infecting one chicken. The sequences obtained from Cryptosporidium sp. infecting guinea pigs were not identified within groups of known Cryptosporidium species. The isolates found parasitizing cats and one dog were diagnosed as C. felis and C. canis, respectively. One isolate of calf origin was identified as C. parvum. The phylogenetic analysis showed clear distribution of isolates between two Cryptosporidium sp. groups according to their gastric or intestinal parasitism. A great genetic distance was observed between C. felis and C. canis from Brazil when compared to the reference sequences obtained from GenBank. The results obtained during this study constitute the first report of rDNA sequences from C. baileyi, C. meleagridis, C. felis, C. canis and C. parvum isolated in Brazil. 相似文献
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Bakheit MA Torra D Palomino LA Thekisoe OM Mbati PA Ongerth J Karanis P 《Veterinary parasitology》2008,158(1-2):11-22
Three LAMP (loop-mediated isothermal DNA amplification) assays were applied to detect Cryptosporidium species DNA in a total number of 270 fecal samples originating from cattle, sheep and horses in South Africa. DNA was extracted from 0.5 g of fecal material. Results of LAMP detection were compared to those obtained by nested PCR targeting the Cryptosporidium 18 small subunit rRNA (18S) gene. All samples were negative by nested PCR, while up to one-third of samples were positive by LAMP assays. The SAM-1 LAMP assay, shown to detect C. parvum, C. hominis and C. meleagridis, amplified Cryptosporidium DNA in 36 of 107 cattle (33.64%), in 26 of 85 sheep (30.5%) and in 17 of 78 horses (21.79%). The HSP LAMP specific to C. muris and C. andersoni, amplified Cryptosporidium DNA in one cow (0.9%), five sheep (5.8%) and seven horses (8.9%). The gp60 LAMP assay, shown to detect C. parvum produced no amplified Cryptosporidium DNA, likely due to low sample DNA concentrations. The specificity of LAMP assays was confirmed by sequencing of the LAMP products generated in positive samples. Sequence products from the three LAMP assays showed high identity to the target gene sequences confirming the specificity of LAMP. In this study, the LAMP procedure was clearly superior to nested PCR in the detection of Cryptosporidium species DNA. Use of LAMP is proposed as an efficient and effective tool for epidemiologic survey studies including screening of healthy animals in which Cryptosporidium oocyst shedding is characteristically low and likely below the detection limit of PCR in conventional sample concentrates. 相似文献
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Cryptosporidium parvum is commonly identified as infecting domestic livestock and humans. Prevalence of C. parvum in pigs has been reported, however, the duration and infection pattern of naturally acquired Cryptosporidium infections in pigs has not been reported. This study was undertaken to investigate the age of oocyst shedding and duration of natural Cryptosporidium parvum infections in pigs from weaning to market weight. Fecal samples were collected from weaned Yorkshire-Landrace piglets (n=33) twice per week until Cryptosporidium oocysts were detected. Upon oocyst detection, fecal samples were collected three times per week and pigs were monitored throughout the study for diarrhea and examined after concentration and immunofluroescent staining. Cryptosporidium isolates were genotyped by polymerase chain reaction to amplify the HSP70 gene which was subsequently sequence analyzed. All 33 pigs shed oocysts some time during the study. The mean age of initial oocyst detection was 45.2 days post-weaning with the mean duration of infection 28.7 days. Mean number of Cryptosporidium oocysts was low and declined to zero prior to study completion. Episodes of diarrhea were not associated with oocyst excretion. Genetic sequences were obtained for 10 of the pigs. All of the 10 isolates aligned as the Cryptosporidium parvum 'pig' genotype. This study demonstrates that the age and duration of oocyst shedding in pigs infected with C. parvum porcine genotype is different from other livestock species. 相似文献
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Fifty faecal samples from diarrheic calves between 1 and 6 months old were collected per rectum from 5 farms around Petaling District in Selangor, Malaysia for Cryptosporidium species detection and genotyping investigation. Oocysts were purified using sedimentation and gradient centrifugation, then examined by immunofluorescence assay (IFAT). Genomic DNA was extracted from all samples and nested PCR was performed to amplify the SSU rRNA gene. Eighteen samples (36%) were positive for Cryptosporidium species by PCR. The sequence and phylogenetic analysis of 14 isolates indicated that Cryptosporidium parvum was most common (11 isolates) followed by Cryptosporidium deer-like genotype (3 isolates). The present work reports the first data on Cryptosporidium genotyping from cattle in Malaysia. 相似文献
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Feng Y Ortega Y He G Das P Xu M Zhang X Fayer R Gatei W Cama V Xiao L 《Veterinary parasitology》2007,144(1-2):1-9
Recent studies in the United States reported that approximately 85% of pre-weaned dairy calves were infected with zoonotic Cryptosporidium parvum, whereas only 1-2% of post-weaned calves and 1-2-year-old heifers were infected with this species. Cryptosporidium bovis and Cryptosporidium deer-like genotype were much more prevalent in the post-weaned animals. It is not clear whether the same infection pattern also occurs in other geographic areas. In this study, to determine whether the same Cryptosporidium infection pattern was present in other geographic areas, we genotyped Cryptosporidium specimens collected from two farms in China and India, using specimens from farms in Georgia, USA for comparison. C. bovis was the most common species found in pre- and post-weaned calves in all three areas. In Georgia, the deer-like genotype was found frequently in pre- and post-weaned calves and Cryptosporidium andersoni was found in one post-weaned calf. Both C. bovis and the deer-like genotype were found in the few milking cows examined in Georgia. There were no differences in the small subunit rRNA gene sequences obtained from C. bovis or deer-like genotype among the three areas. One adult yak in China, however, was infected with a species similar to C. bovis, with only three nucleotide mutations in the target gene. All four common bovine Cryptosporidium spp. were differentiated from each other by restriction fragment length polymorphism analysis of PCR products with enzymes SspI and MboII. Thus, both C. bovis and the deer-like genotype are found in all age groups of cattle in diverse geographic areas and host adaptation of C. bovis might have occurred in yaks. 相似文献