宿主日龄对艾美耳球虫（Eimeria）早熟虫株感染力及雏鸡球虫免疫力的影响

用1000个柔嫩艾美耳球虫(E.tenella)早熟株孢子化卵囊,1000个毒害艾美耳球虫(E.necatrix)早熟株孢子化卵囊和500个巨型艾美耳球虫(E.maxima)早熟株卵囊分别接种1,7和25日龄雏鸡,接种后14天分别用相应的200,200和100个亲本毒株孢子化卵囊进行攻虫.初次接种和攻虫后分别检查卵囊总产量.结果表明,3种早熟虫株的卵囊都能够成功的感染1日龄和7日龄雏鸡.初次接种后雏鸡都产生了不同程度的球虫免疫力.本研究证实,艾美耳球虫早熟株卵囊能够诱导初生和幼龄雏鸡产生球虫免疫力.     

宿主日龄对艾美耳球虫 (Eimeria)早熟虫株感染力及雏鸡球虫免疫力的影响(英文)

用 10 0 0个柔嫩艾美耳球虫 (E .tenella)早熟株孢子化卵囊 ,10 0 0个毒害艾美耳球虫 (E .neca trix)早熟株孢子化卵囊和 5 0 0个巨型艾美耳球虫 (E .maxima)早熟株卵囊分别接种 1,7和 2 5日龄雏鸡 ,接种后 14天分别用相应的 2 0 0 ,2 0 0和 10 0个亲本毒株孢子化卵囊进行攻虫。初次接种和攻虫后分别检查卵囊总产量。结果表明 ,3种早熟虫株的卵囊都能够成功的感染 1日龄和 7日龄雏鸡。初次接种后雏鸡都产生了不同程度的球虫免疫力。本研究证实 ,艾美耳球虫早熟株卵囊能够诱导初生和幼龄雏鸡产生球虫免疫力     

鸡柔嫩艾美耳球虫表面抗原基因sag10在毕赤酵母中的表达及鉴定

sag基因家族是制备基因工程疫苗重要的候选基因。本研究通过在毕赤酵母Pichiapastoris中表达柔嫩艾美耳球虫Eimeriatenella表面抗原基因sag10,来探讨sag10表达后的生物学活性。本文首先提取柔嫩艾美耳球虫北京株第2代裂殖子总RNA,根据GenBank报道序列(AJ586552)设计引物,应用RT-PCR技术扩增得到鸡球虫表面抗原sag10基因。然后将sag10与真核表达载体pPIC9K连接,构建了pDQ052分泌型真核表达质粒,并转化毕赤酵母GS115,利用G418抗性筛选多拷贝重组菌株,进行优化表达。SDS-PAGE和Westernblot检测表达结果,在43kDa处有明显的免疫印迹条带,表明目的蛋白得到表达,而且能被特异性抗体所识别,说明表达的SAG10蛋白具有生物学活性。     

鸡球虫卵囊的三种同工酶酶谱分析

者对3种艾美耳球虫和4株柔嫩艾美耳球虫抗药性虫株分别进行了乳酸脱氢酶(LDH)、葡萄糖磷酸异构酶(GPI)、葡萄糖-6-磷酸脱氢酶(G6PD)同工酶电泳图谱分析。其中LDH同工酶谱共观察到5条酶带,GPI同工酶谱共观察到8条酶带,G6PD同工酶谱观察到7条酶带。3种艾美耳球虫的同工酶谱存在种间差异,不同抗药性虫株间酶谱也存在差异。G6PD-5很可能与球虫对氯嗪苯乙氰的抗药性有关,G6PD-2则可能与球虫对氯羟吡啶的抗药性有关     

福建三株柔嫩艾美耳球虫的分离、鉴定及致病性的初步研究

采用单卵囊分离技术,从福建省莆田市、福清市和连江县等三地鸡场的病鸡盲肠内容物样品中,分离获得3株柔嫩艾美耳球虫Eimeria tenella,代号分别为PT0705、FQ0709和LJ0711.为比较这3株柔嫩艾美耳球虫的致病性,分别用1×104、5×104和10×104个孢子化卵囊的剂量感染14日龄和21日龄健康无球虫雏鸡,通过临床表现、死亡率、增重、病变计分等指标进行统计和分析,确定PT0705为毒性最强虫株.     

山东省聊城地区肉鸡球虫的抗药性调查

应用石歧杂肉仔鸡,检测了采自我国山东聊城的４种艾美耳球虫对６种常用抗球虫药的敏感性。根据最适抗球虫活性百分率、相对卵囊产量和病变记分减少率３项指标综合判定,山东聊城地区的柔嫩艾美耳球虫、堆型艾美耳球虫、巨型艾美耳球虫和布氏艾美耳球虫的４种球虫混合感染对盐霉素Ｓａｌｉｎｏｍｙｃｉｎ（赛可喜Ｓａｃｏｘ）、拉沙里菌素Ｌａｓａｌｏｃｉｄ（球安Ａｖａｔｅｃ）、莫能霉素Ｍｏｎｅｎｓｉｎ（欲可胖Ｅｌａｎｃｏｂａｎ）、马杜拉霉素Ｍａｄｕｒａｍｉｃｉｎ（抗球王ＫＱＷ）和常山酮Ｈａｌｏｆｕｇｉｎｏｎｅ（速丹Ｓｔｅｎｏｒａｌ）均存在不同程度的抗药性,其中对抗球王和欲可胖有重度抗药性,对球安、速丹和赛可喜具有中度抗药性。４种艾美耳球虫混合感染对氯嗪苯乙氰Ｄｉｃｌａｚｕｒｉｌ（伏球Ｃｌｉｎａｃｏｘ）无抗药性。尽管４种艾美耳球虫混合感染对赛可喜具有中等程度的抗药性,在增重方面却优于伏球。     

柔嫩艾美耳球虫田间分离株对马杜霉素耐药性检测

以对马杜霉素完全敏感和柔嫩艾美耳球虫豪顿株为参照 ,检测柔嫩艾美耳球虫 2个河北分离株(HBZ、HBH)、 2个山东分离株 (SDZ、SDT)对马杜霉素的耐药程度。按每羽 5× 1 0 4个孢子化卵囊的剂量接种 7日龄试验鸡只 ,接种后第 7天剖杀所有试验鸡 ,观察盲肠病变 ,计算平均增重、盲肠内容物卵囊数、粪便中卵囊排出量和抗球虫指数 (ACI)。以ACI值作为判定耐药程度的标准 ,ACI≥ 1 80判为敏感 ,1 6 0≤ACI<1 80判为部分耐药 ,ACI<1 6 0判为耐药。结果是柔嫩艾美耳球虫豪顿株的ACI为 1 98 3,柔嫩艾美耳球虫河北分离株HBZ、HBH组的ACI分别是 1 4 7 5、 1 5 3 7,山东分离株SDZ、SDT组的ACI分别是1 2 7 2、 1 30 0。试验证明柔嫩艾美耳球虫 2个河北分离株 (HBZ、HBH)、 2个山东分离株 (SDZ、SDT)对马杜霉素具有耐药性     

兔球虫PCR检测方法的改进和应用

兔球虫病由艾美耳属球虫寄生于消化道而引起,对养兔业的危害极大。由于兔艾美耳球虫的11个虫种在致病性上有较大差异,因此进行准确的虫种鉴定对兔球虫病的诊断和防治有十分重要的意义。为提高和扩大PCR方法检测粪便样品中艾美耳球虫的灵敏度和应用范围,我们利用全基因组扩增技术对提取自粪便样品的球虫基因组进行预扩增,提高PCR反应初始模板含量,再利用兔艾美耳球虫ITS-1序列种特异性引物对WGA产物进行PCR扩增,以鉴定虫种。结果显示,经全基因组扩增后的样品的PCR检测能够在单个卵囊的水平上进行虫种鉴定。利用该方法,我们对10份卵囊含量较少的田间兔粪样品进行了PCR检测,对其中的虫种进行了的鉴定。检测结果显示,与卵囊形态鉴定相比,该方法不仅与能确定形态的形态学检测结果一致,还能够检测出形态学不易判断的虫种,体现了更高的准确性。该技术的应用可提高田间样品检测的敏感性和准确度,为兔球虫临床感染情况提供实践指导。     

三株柔嫩艾美耳球虫(Eimeria tenella)的繁殖力和免疫原性的比较研究

分别用柔嫩艾美耳球虫早熟弱毒株、鸡胚适应株和强毒株孢子化卵囊１０００个／只，给１０日龄无球虫雏鸡免疫接种，逐日检查粪便并进行克粪便卵囊（Ｏ．Ｐ．Ｇ．）计数，结果发现早熟弱毒株和鸡胚适应株的潜隐期均有不同程度缩短，繁殖力亦有不同程度的下降。同时进行了柔嫩艾美耳球虫不同株球虫的免疫原性比较：分别用三株卵囊免疫雏鸡，免疫剂量为１０００个／只，免疫后１４ｄ各用１０００个／只强毒株卵囊攻虫，逐日进行Ｏ．Ｐ．Ｇ．计数，发现各组免疫鸡攻虫后的卵囊产量均大大下降，其中以强毒株免疫攻虫组的排出卵囊量最低，仅为未免疫组的１．２３％，早熟株和鸡胚株免疫鸡攻虫的排出卵囊量相近，分别为未免疫组的７．３５％和７．２３％。由此可见，三株柔嫩艾美尔球虫均表现出良好的免疫原性。     

柔嫩艾美耳球虫（E.tenella）BJ株TA4基因的克隆的序列分析

对柔嫩艾美耳球虫（Ｅ．ｔｅｎｅｌｌａ）ＢＪ株ＴＡ４基因进行了克隆和测序分析。经纯化的Ｅ．ｔｅｎｅｌｌａＢＪ株７ｈ孢子化卵囊的总ＲＮＡ为模板，根据国外报道的序列设计一对引物，用ＲＴ－ＰＣＲ方法扩增出ＢＪ虫株的ＴＡ４基因。用常规基因克隆方法把ＢＪ株ＴＡ４基因插入ｐＧＥＭ－Ｔ克隆载体，选取正方向插入的一个阳性克隆进行酶切分析及插入片段的全序列测序分析。结果表明：该序列全长１２２７个核苷酸，有一个含２３０     

Eimeria: immunisation of young chickens kept in litter pens

Infection of chickens with an attenuated strain of Eimeria tenella gave good protection against challenge with the parent strain of this species. Chickens given an attenuated strain of E. acervulina var. mivati were protected against challenge with other pathogenic cultures of E. acervulina when kept in litter pens under conditions allowing reinfection. Two-week-old chickens, kept in litter pens, were given attenuated strains of E. tenella and E. acervulina and small numbers of oocysts (50-100) of E. brunetti, E. maxima and E. necatrix. Body weight gain was unaffected and resistance to challenge infection was demonstrated at 6 and 9 weeks after inoculation. In other experiments only a small proportion of 1 to 3-week-old chickens in each pen were given oocysts. Chickens placed in contact with these 'seeder' chickens were immunised against five species of Eimeria within a 2 to 4 week period. Similar experiments with 1-week-old chickens showed that these could also be immunised but the degree of parasitism during immunisation caused some weight gain depression. These results suggest that controlled immunisation against several species of Eimeria may be possible and further experiments are needed under conditions which more closely resemble those operating in the field.     

PCR identification of chicken Eimeria: a simplified read-out.

A polymerase chain reaction (PCR) assay, based on the amplification of internal transcribed spacer 1 (ITS1) regions of ribosomal DNA, was developed for the chicken coccidian species Eimeria maxima, E. mitis and E. praecox. Thus, taking into account our previous work, a complete set of ITS1-based, species-specific primers for the detection and discrimination of all seven Eimeria species that infect the domestic fowl is now available. ITS1 primers for each of these seven species of Eimeria were also used as capture probes in a paper chromatography assay (PACHA). The addition of PACHA to the PCR assay provided a faster, more simplified read-out compared to staining of amplified bands in an agarose gel with ethidium bromide.     

Eimeria parasites of domestic fowl: genetic relationships of different isolates estimated from random amplified polymorphic DNA

Genetic relationships between Eimeria parasites of domestic fowl, including three isolates of E. acervulina, one of E. maxima, four of E. mitis, six of E. praecox, one of E. tenella, and two of uncertain identity, were analyzed by random amplified polymorphic DNA (RAPD) and the unweighted pair-group method with arithmetic mean, using 12 primers. Each primer amplified 4-34 DNA fragments/isolate. The similarity coefficients and phenograms were calculated from RAPD products with 230-2,000 bp in silver-stained polyacrylamide gels. Some primers generated RAPD markers which were species-specific for E. acervulina, E. mitis, and E. praecox. The phenograms revealed six clusters, each corresponding to an individual Eimeria species. The pBP and pBP2 isolates, of uncertain identity, clustered with the E. acervulina isolates (100% bootstrap). The intraspecific relationships showed certain degree of genetic isolation of the Eimeria populations, and it was associated with broiler house and with geographic separation.     

Mitochondrial RNA polymerase is an essential enzyme in erythrocytic stages of Plasmodium falciparum

Apicomplexan parasites are serious pathogens of animals and man that cause diseases including coccidiosis, malaria and toxoplasmosis. The importance of these parasites has prompted the establishment of genomic resources in support of developing effective control strategies. For the Eimeria species resources have developed most rapidly for the reference Eimeria tenella Houghton strain (http://www.genedb.org/Homepage/Etenella). The value of these resources can be enhanced by comparison with related parasites. The well characterised immunogenicity and genetic diversity associated with Eimeria maxima promote its use in genetics-led studies on coccidiosis and recommended its selection for sequencing. Using a combination of sequencing technologies a first draft assembly and annotation has been produced for an E. maxima Houghton strain-derived clone (EmaxDB; http://www.genomemalaysia.gov.my/emaxdb/). The assembly of a draft genome sequence for E. maxima provides a resource for comparative studies with Eimeria and related parasites as demonstrated here through the identification of genes predicted to encode microneme proteins in E. maxima.     

基于IFA技术检测微线体蛋白2在艾美耳属球虫的空间分布

微线体蛋白2（Microneme protein2,Mic2）是艾美耳球虫入侵宿主细胞时分泌的主要功能蛋白之一。本研究中,以抗柔嫩艾美耳球虫微线体蛋白2（EtMic2）单克隆抗体为检测抗体,利用间接免疫荧光实验（IFA）检测了Mic2在柔嫩艾美耳球虫、和缓艾美耳球虫、斯氏艾美耳球虫和无残艾美耳球虫等不同种艾美耳属球虫的空间分布。结果显示,Mic2在不同种艾美耳属球虫中均定位于子孢子的顶部（微线体部位）,但表达强度存在差异。这提示Mic2可作为研究艾美耳属球虫相关蛋白空间分布的“参照物”。     

Intraspecific polymorphisms of Eimeria species due to resistance against anticoccidial drugs

 Resistance analyses were done on 15 Eimeria acervulina strains and 5 E. brunetti strains. In all, 55% of these strains proved to have complex profiles of resistance to anticoccidial drugs as judged by resistance-index (RI) evaluation. Genomic fingerprints generated by random amplified DNA (RAPD) with 16 primers via the polymerase chain reaction (PCR) revealed a high degree of similarity (SI) between nonresistant strains (SI up to 95%). Polymorphisms including band shifts, differences in banding intensity, and missing bands led to significantly low SI values (57%, 69%, 82%) in drug-resistant Eimeria strains. After experimental induction of diclazuril resistance (1, 2, and 4 ppm) in a laboratory isolate VT-1 primer 5′-CCC TGA GAT GGG AAC CTC-3′ amplified a polymorphic band of around 600 bp. Polymorphisms detected by RAPD-PCR will facilitate the selection of molecular markers and might lead to the design of diagnostic tests for drug-resistant genotypes. Received: 20 March 1996 / Accepted: 18 April 1996     

2010年广州市甲型H1N1流感病毒分离株HA基因变异分析

目的比较2010年广州市分离到的甲型H1N1流感病毒血凝素（HA）基因和2009年中国大陆甲型H1N1流感病毒HA基因的变异情况,为甲型H1N1流感的监测和防控提供理论依据。方法收集2010年广州市有发热和呼吸道症状病人的咽拭子标本,用H1N1流感特异性引物进行PCR检测,扩增分离到的H1N1病毒HA片段,测序后与2009年的H1N1毒株进行比对和分析,并用生物信息学方法对抗原位点和糖基化位点进行分析。结果共收集到426份标本,甲型流感阳性211份,其中H1N1流感4株,与2009年分离的甲型H1N1流感相比,有12个氨基酸碱基位点发生了有意义突变,其中6个位点位于抗原位点上;4株毒株HA基因145位氨基酸都发生了变异;其中2株毒株在第180位氨基酸位点的抗原位点发生了变异。进化分析表明4株毒株与2009年中国大陆分离的8株毒株进化关系较远。结论 2010年广州市甲型H1N1毒株与2009年相比发生了较大变异。HA基因145位和180位氨基酸位点变异对H1N1毒株抗原变异有重要意义。本文分离的A/Guangdong/ZS03/2010（H1N1）和A/Guangdong/ZS01/2010（H1N1）毒株可能已经发生了抗原性漂移。     

Development of a diagnostic PCR assay for the detection and discrimination of four pathogenic .Eimeria species of the chicken.

We describe a polymerase chain reaction (PCR)-based assay for the detection, identification and differentiation of pathogenic species of .Eimeria in poultry. The internal transcribed spacer 1 (ITS1) regions of ribosomal DNA (rDNA) from .Eimeria acervulina, E. brunetti, E. necatrix and .E. tenella were sequenced and regions of unique sequences identified. Four pairs of oligonucleotide primers, each designed to amplify the ITS1 region of a single .Eimeria species, were synthesised for use in the PCR assay. In tests on purified genomic DNA from all seven species of .Eimeria that infect the chicken, each of the four primer pairs amplified the ITS1 region from only their respective target species. The robustness of the approach was further demonstrated by the amplification of specific DNA fragments from tissues of experimentally infected animals and from oocysts recovered from field samples. We conclude that the ITS1 regions of .Eimeria species contain sufficient inter-specific sequence variation to enable the selection of primers that can be applied in PCR analyses to detect and differentiate between species. In future work they may provide excellent markers for epidemiological studies.     

16SrRNA基因在快速诊断新生儿败血症的病原菌研究

目的探讨血液16SrRNA基因检测在新生儿败血症诊断中的应用价值。方法分析细菌16SrRNA基因保守区，设计一对通用引物扩增已知实验菌株，检测其特异性，用倍比稀释法检测其敏感性，同时进行血培养。结果已知实验菌株均获得920bp扩增产物，对照组中的人类基因组DNA、HBV—DNA和白色假丝酵母菌无相应产物。敏感性测试能达到lpg大肠杆菌DNA。PCR阳性率为31．7％（20／63），血培养阳性率为14．3％（9／63），两者比较有显著性差异（P〈0.05）。结论PCR检测血液细菌16SrRNA基因，具有特异性强，敏感度高等特点，能在临床推广应用。