不同亚型人隐孢子虫和微小隐孢子虫生物学特性研究

发布时间：2018-03-15 17:24

本文选题：人隐孢子虫　切入点：流行病学　出处：《河南农业大学》2010年硕士论文　论文类型：学位论文

【摘要】：目前国内少有的一些研究表明人主要感染人隐孢子虫(Cryptosporidium hominis),但C. hominis群体遗传结构尚不清楚,从而不能推断人隐孢子虫病的感染来源和传播机制。本课题对开封地区人源隐孢子虫分离株以基于SSU rRNA基因的PCR-RFLP方法为主要工具进行种类和基因型鉴定、以GP60基因位点进行亚型分析,从而解析C. hominis群体遗传结构,初步总结出人隐孢子虫病的流行规律和传播机制。并用C. hominis不同亚型分离株感染蒙古沙鼠、新生仔猪和羔羊,观察其临床症状和病理变化,从而研究不同亚型之间的生物学差异。同时对国内主要C. hominis和微小隐孢子虫(C. parvum)基因亚型进行致病性研究,了解国内医学上主要隐孢子虫种生物学特性,以期为隐孢子虫公共卫生安全屏障的建立起到有效推动作用。开封是国家精品旅游城市,以其独特的旅游资源和深厚的旅游文化,每年接纳数亿海内外游客,人员流动性大,有利于机会性人兽共患寄生虫传播流行。为了解开封地区临床病人隐孢子虫感染状况,用饱和蔗糖溶液漂浮法、甲醛-乙酸乙酯-改良抗酸染色法对该地区门诊和住院病人6 093份粪便样品进行了检查。结果检出隐孢子虫感染率为0.1%,秋季为感染高峰期,6岁以下儿童感染率较高。所有分离株均为C. hominis,Ib亚型家族占5/6,Ia亚型家族1/6。研究表明开封地区临床病人隐孢子虫感染率较低,但仍应进一步开展健康教育,普及卫生知识,提高自我保健意识和自我保健能力,预防食源性寄生虫病的发生和流行。目前国内一些研究表明人主要感染人隐孢子虫(Cryptosporidium hominis),但已获取且传代保存的国内C. hominis分离株较少,C. hominis生物学特性研究未见报道。在本试验自感染前第10d起,采用胃导管灌服地塞米松抑制蒙古沙鼠(Meiiones Unguiculataus)免疫力直至排卵囊结束后14d,对国内C. hominis Ib亚型分离株进行生物学特性研究。结果显示,感染后3d,感染组有卵囊排出,感染后第6d出现高峰期,此后逐渐下降直至感染后10或11d排卵囊结束。感染前后基于18S rRNA和gp60基因分析,表明遗传学无差异。建立了持续稳定的C. hominis Ib亚型分离株啮齿动物模型,为C. hominis卵囊扩增和进一步研究其生物学特性等提供了重要的参考依据。为了寻求更为经济有效的C. parvum卵囊保种传代方法,将19日龄蒙古沙鼠随机分成5组,免疫抑制对照组和感染组采用胃导管灌服地塞米松0.80mg·只-1·2d-1,10d后,感染组沙鼠灌胃接种C. parvum卵囊,对排卵囊规律,临床表现及组织学和超微结构进行了观察。结果感染后第2d有卵囊排除,显露期OPG值近似于犊牛实验,且持续时间较犊牛感染长,为C. parvum卵囊保种传代提供了更为经济的实验方法。为了初步确定人隐孢子虫同一亚型家族内不同亚型是否存在生物学表型差异,用分离自开封地区某医院的C. hominis分离株ZZH-1 (IbA20G2)和WJH-35 (IbA19G2)感染新断奶蒙古沙鼠,3日龄羔羊和仔猪;通过比较感染后动物的临床症状、虫体寄生部位、寄生量和病理变化并测定感染动物的排卵囊规律、体重变化等一系列指标来初步确证不同亚型人隐孢子虫致病性差异。研究结果显示,不同亚型人隐孢子虫的致病作用存在一定差异,为下一步隐孢子虫毒理的深入研究奠定了理论基础。为了研究人隐孢子虫(Cryptosporidium hominis IbA19G2)和微小隐孢子虫(C. parvum IIdA19G1)对新生仔猪的致病性差异。将3日龄新生仔猪随机分为三组,经口感染不同基因型隐孢子虫,对排卵囊规律,临床表现及病理变化进行观察。结果C. hominis感染后潜隐期和显露期均较C. parvum长,显露期C. parvum平均OPG值大于C. hominis,感染后仔猪体重变化存在统计学差异,C. hominis对体重影响较为严重。表明两虫株对新生仔猪致病性存在差异。
[Abstract]:At present, few studies show that people who infect Cryptosporidium (Cryptosporidium hominis), but the C. hominis population genetic structure is not clear, thus cannot infer Cryptosporidium infection sources and transmission mechanism. The research on insect human Cryptosporidium Kaifengs isolates by PCR-RFLP SSU based on rRNA gene as the main tool for identification of species and genotypes, GP60 gene loci were subtype analysis and genetic analysis of C. hominis population structure, summarizes cryptosporidiosis epidemiology and transmission mechanism. And C. strains of different subtypes of hominis infection in Mongolia gerbils, newborn piglets and lamb, observe the clinical symptoms in order to study the biological and pathological changes, the difference between different subtypes. At the same time to the domestic main C. hominis and Cryptosporidium parvum (C. parvum) of pathogenic gene subtypes, To understand the biological characteristics of the main Cryptosporidium species in domestic medicine, in order to promote the establishment of the public health safety barrier of Cryptosporidium.
It is the national excellent tourist city, with its unique tourism resources and deep cultural tourism, every year millions of tourists from home and abroad, staff mobility, to spread opportunistic parasites. In order to understand the clinical patient Kaifengs Cryptosporidium infection status by saturated sucrose flotation method, formaldehyde - ethyl acetate check - modified acid fast staining in the area of outpatient and inpatient 6093 fecal samples. Results the detection of Cryptosporidium infection rate was 0.1%, autumn is the peak of infection, high rate of children under the age of 6. The infection isolates were C. hominis, Ib subtype family accounted for 5/6, 1/6. Ia sub family study that type of Kaifengs clinical patient Cryptosporidium infection rate is low, it is necessary to further carry out health education, popularization of health knowledge, improve self-care awareness and self-care ability, prevention of food borne parasites The occurrence and prevalence of disease.
At present, some studies show that people who infect Cryptosporidium (Cryptosporidium hominis), but they have been preserved and the passage of the domestic C. hominis isolates less study on the biological characteristics of hominis C. have not been reported. In this article 10d test before infection, the gastric catheter perfusion of dexamethasone suppression (Meiiones Unguiculataus) in Mongolia until immunity after the end of pvax-cp15-p23-cp15 14d, biological characteristics research of domestic C. hominis Ib isolates. The results showed that after 3D infection, infection group oocyst discharge after 6D infection, reached the peak, then decreased gradually until 10 11d after infection or oocyst infection before and after rRNA and 18S. The end of the gp60 gene based on analysis showed that no differences in genetics. Established a stable C. hominis subtype Ib strains rodent models, C. and hominis were amplified in order to further study the biological characteristics of extraction It provides an important reference basis.
In order to seek a more economical and effective method to ensure the passage of C. parvum oocysts, 19 day old Mongolia gerbils were randomly divided into 5 groups, control group and immunosuppressive infection group with gastric gavage catheter 0.80mg -1 dexamethasone 2d-1,10d after infection group gerbils were orally inoculated C. parvum oocysts of pvax-cp15-p23-cp15 of clinical manifestations and the histology and ultrastructure were observed. Results the infection after 2D oocysts exclusion, revealed OPG is approximate to the experimental calves, and the duration is calves infected long, provide more experimental methods for economic C. parvum oocysts FVB.
In order to preliminarily determine the Cryptosporidium hominis same subtype family in different subtypes of the existence of biological phenotypes, isolated from a hospital for Kaifengs C. hominis isolate ZZH-1 (IbA20G2) and WJH-35 (IbA19G2) infection in newly weaned Mongolia gerbils, 3 day old piglets and lamb; through the comparison of clinical symptom after infection of the animal and parasitic site, and the pathological changes and determination of oocyst infection of parasitic animal, weight change and a series of indicators to preliminarily confirmed that different subtypes of Cryptosporidium hominis pathogenicity difference. The results of the study show that there are some differences in pathogenicity of different subtypes of Cryptosporidium hominis, laid the theoretical foundation for the in-depth on the next step of Cryptosporidium toxicology.
In order to study the Cryptosporidium hominis (Cryptosporidium hominis IbA19G2) and Cryptosporidium parvum (C. parvum IIdA19G1) on the pathogenicity of newborn piglets. 3 day old newborn piglets were randomly divided into three groups, oral infection of different genotypes of Cryptosporidium oocyst, law, clinical manifestation and pathological changes were observed. The results of C. after hominis infection, latent period and exposure period were lower than C. parvum, C. parvum OPG revealed the average value is greater than C. hominis, there was significant difference in piglet weight changes after infection and effect of C. hominis on body weight is more serious. Showed that two strains of piglet pathogenic differences.

【学位授予单位】：河南农业大学
【学位级别】：硕士
【学位授予年份】：2010
【分类号】：R382.3;S852.7

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