柔嫩艾美耳球虫（E，Etenella）马杜拉霉素抗药株和敏感株孢子化卵囊的蛋白质差异分析

利用双向电泳技术，对本实验室诱导保存的柔嫩艾美耳球虫马杜拉霉素抗药株与敏感株的蛋白质表达图谱进行差异比较和分析，发现两者之间差异有4个蛋白质斑点，利用MALDI—TOF—TOF质谱技术对3个差异明显的蛋白质斑点进行分析鉴定，获得3个明确的肽质量指纹图谱，通过在NCBInr数据库中检索分析，确定了其中1种蛋白质为球虫子孢子表面抗原TA4。另外2种蛋白质与疟原虫的Pfjl和线粒体转运蛋白受体Tom40具有很高的同源性，上述蛋白的鉴定将对球虫的抗药性产生机理和柔嫩艾美耳球虫马杜拉霉素抗药株的分之标志物提供了研究方向。     

柔嫩艾美耳球虫马杜拉霉素抗药株与敏感株的mRNA差异显示

利用柔嫩艾美耳球虫马杜霉素敏感虫株裂殖子和抗药虫株裂殖子为材料,对马杜霉素敏感虫株和抗药虫株进行差异显示PCR,共回收34条电泳差异片段,反向Northern点杂交鉴定4个片段为真正差异片段,并对4个片段进行测序、B1ast同源性比较.来自于马杜霉素抗药虫株裂殖子的ACD3-2序列与柔嫩艾美耳球虫微线-5同源性99%,说明AcD3-2序列是该基因的部分序列,微线-5蛋白与虫体融解宿主细胞膜、入侵、运动和溢出有关,在第二代裂殖子时期,抗药性虫株该序列发生转录,而在敏感虫株中沉默;HCD1序列来自马杜霉素敏感虫株,与柔嫩艾美耳球虫表面抗原16和17序列同源性分别为83%和86%,说明与这2个基因同源.AGD5片段来自抗药虫株,HAD8-2序列来自敏感虫株,通过比较这2条序列可能为新序列.     

柔嫩艾美耳球虫地克珠利抗药株和马杜拉霉素抗药株的实验室诱导

采用药物浓度逐渐递增的方法 ,以 0 .0 5× 10 - 6 地克珠利和 2 .0× 10 - 6 马杜拉霉素为起始诱导浓度 ,分别经过 18次和 2 0次传代 ,在实验室诱导了柔嫩艾美耳球虫 (Eimeria tenella)对地克珠利和马杜拉霉素的抗药性虫株。经抗药性检测 ,以最适抗球虫指数 (POAA)、病变记分减少率 (RL S)、相对卵囊产量 (ROP)和抗球虫指数 (ACI) 4项指标综合判定及综合抗药性指数 (GI) 2种方法共同判定 ,获得的地克珠利抗药株对 1.2× 10 - 6地克珠利具有完全抵抗力 ,而对马杜拉霉素完全敏感 ;马杜拉霉素抗药株对 7.0× 10 - 6 的马杜拉霉素具有完全抵抗力 ,而对地克珠利完全敏感。     

柔嫩艾美球虫地克珠利和马杜拉霉素抗药株与敏感株孢子化卵囊18SrDNA基因的差异

为探讨抗球虫药物地克珠利和马杜拉霉素对柔嫩艾美球虫18SrDNA的影响，分别对人工诱导的柔嫩艾美球虫地克珠利抗药株（ETAD）、马杜拉霉素抗药株（ETAM）和药物敏感株（ETDS）孢子化卵囊的18SrDNA基因进行了克隆测序，并通过生物信息软件进行对比差异分析。结果显示，ETAM株有3个碱基发生突变（T170突变为C，T646突变为C，G694突变为C）；ETAD株有1个碱基发生突变（T646突变为C）。经进一步分析比较，发现ETAM株18SrRNA的二级结构与ETDS株的差异很大，而ETAD株18SrRNA的二级结构则与ETDS株的完全相同。这些碱基的突变有可能是导致E．tenella产生抗药性的原因之一。     

马杜霉素对柔嫩艾美耳球虫(Eimeria tenella)超微结构的影响

将马杜霉素按 0 .0 0 0 5 %的比例混入饲料 ,作用于鸡体内柔嫩艾美耳球虫 (Eimeria tenella) ,透射电镜观察 ,发现裂殖体变小 ,内含裂殖子的数目减少 ,裂殖子膨胀变为椭圆 ,裂殖子间 (带虫空泡内 )微管结构模糊、膨胀 ,裂殖体中有髓鞘样结构出现 ;细胞膜外突和细胞质分离形成空隙 ,细胞膜有破损、结构模糊 ;细胞质出现空泡化 ,内部出现附加体和髓鞘样结构 ;少数细胞核的外膜外突和内膜分离 ,有的部位的核膜模糊、破损。裂殖子顶体结构发生异常变化 ,棒状体消失 ,微线数目减少或者消失。线粒体表现为形态改变 ,肿大变圆 ,或者变为马蹄形 ,内膜和嵴脱落 ,内部形成空泡、膜状结构、螺旋状或者髓样结构 ,线粒体的嵴与长轴平行排列 ,且贯穿线粒体。作者推测 ,抗生素类抗球虫药的作用机理可能是 ,通过使虫体结构的完整性受损 ,抑制虫体的物质代谢及能量代谢等生理机能 ,达到杀死虫体或者抑制虫体生长、发育和繁殖的目的。     

鸡柔嫩艾美耳球虫敏感株与马杜拉霉素耐药株EST-SSR信息分析

从NCBI公共数据库获得2806条柔嫩艾美耳球虫敏感株与马杜拉霉素耐药株表达序列标签(EST),通过前处理得到全长为421.186kb的无冗余EST共1519条。在这些序列中搜索出202个简单重复序列(SSR),分布于1519条EST中,出现频率是17.45%。三核苷酸重复和四核苷酸重复是主要的类型,其中三核苷酸占67.92%,四核苷酸占25.28%,占总SSR的近93.20%。AAG/CTT和ACGT/ATGC是三、四核苷酸中的优势重复类型,分别占三、四核苷酸重复的62.72%和56.76%。     

柔嫩艾美耳球虫盐霉素耐药株的实验室诱导

为了研究耐药性柔嫩艾美耳球虫产生耐药性的机理,本研究在实验室条件下,采用药物浓度递增的方法,以15 mg/kg为起始诱导浓度,对柔嫩艾美耳球虫盐霉素耐药性进行诱导.经过10次传代,获得了对60 mg/kg盐霉素耐药的柔嫩艾美耳球虫虫株.以抗球虫指数、最适抗球虫活性百分率、病变记分减少率和相对卵囊产量四项指标综合判定柔嫩...     

柔嫩艾美耳球虫地克珠利抗药株的实验室诱导

采用药物浓度递增法,以0．07mg／L地克珠利为起始诱导浓度连续传代,以最适抗球虫指数（POAA）、病变记分减少率（RLS）和相对卵囊产量（ROP）3项指标综合判定抗药性。经12次传代,该诱导虫株对1．5mg／L地克珠利具有完全抵抗力。试验结果表明,用实验室方法诱导柔嫩艾美耳球虫抗药株完全可行。     

2株柔嫩艾美耳球虫对5种抗球虫药的抗药性

选择130只21日龄雏鸡，研究了柔嫩艾美耳球虫（E.tenella)南京株和凤阳株对地克珠利（Diclazuril)、马杜霉毒（Maduramicin)、氯羟吡啶（Clopidol)、氯苯胍（Robenidine)和氨丙啉（Amprolium)的抗药性。试验鸡随机分成13组，其中每株球虫均设5个感染用药组，1个感染不用药组，另设1个不感染不用药组，每组10只鸡。以POAA，RLS，ROP，ACI作为指标。结果表明，2株柔嫩艾美耳球虫均对氨丙啉轻度抗药，对地克珠利敏感或轻度抗药，对氯羟吡啶中度抗药。对马杜霉和氯苯胍中度抗药或安全抗药。提示：目前在凤阳地区可合理地使用地克珠利和氨丙啉，对氯羟哟啶应慎用，对马杜霉素和氯苯胍须减少或暂停使用。     

柔嫩艾美耳球虫YL株抗药性研究

用柔嫩艾美耳球虫杨凌株 ( YL t)对 1 4日龄雏鸡进行感染 ,检测了该虫株对 4种常用抗球虫药 (马杜拉霉素、地克珠利、克球粉和氯苯胍 )的敏感性。以最适抗球虫活性百分率、抗球虫指数、相对卵囊产量和病变记分减少率为指标 ,进行综合评定 ,其抗药程度分为无抗药性、轻度抗药性、中度抗药性和完全抗药性 4个等级。结果表明 ,该虫株对马杜拉霉素有轻度抗药性 ,对地克株利有完全抗药性 ,对克球粉和氯苯胍无抗药性。     

Comparison of proteome and antigenic proteome between two Neospora caninum isolates

This study was conducted to explore the relationship between two isolates of Neospora caninum (N. caninum) (KBA-2 and VMDL-1) using proteomics. To achieve the goal, proteins of N. caninum tachyzoite lysates of KBA-2 and VMDL-1 were separated by two-dimensional gel electrophoresis (2-DE), stained with silver-nitrate and analyzed using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) to compare protein profiles. In addition, proteins separated by 2-DE were transferred to membranes, probed with bovine anti-N. caninum KBA-2 immunoglobulin G, and reactive proteins were visualized and compared between the two isolates. Most spots on 2-DE profiles and antigenic spots on 2-DE immunoblot profiles were located at similar locations in terms of isoelectric point and molecular weight. Proteins common to both isolates included the following: heat shock protein 70, subtilisin-like serine protease, nucleoside triphosphatase, heat shock protein 60, pyruvate kinase, tubulin alpha, tubulin beta, enolase, putative protein disulfide isomerase, actin, fructase-1,6-bisphosphatase, putative ribosomal protein S2, microneme protein Nc-P38, lactate dihydrogenase, fructose-1,6-bisphosphatase aldolase, serine threonine phosphatase 2C, 14-3-3 protein homologue, N. caninum dense granule-1 and NcGRA2. As a consequence, even though N. caninum KBA-2 and VMDL-1 isolates were isolated from geographically distinct locations there were significant homology in the proteome and antigenic proteome profiles. In addition, proteomic approach was verified as a useful tool for understanding of host immune response against different isolates of protozoa.     

不同毒力牛传染性鼻气管炎病毒感染MDBK细胞的差异蛋白组学

毒力不同的中传染性鼻气管炎病毒(IBRV)株感染宿主细胞后,会产生不同的临床免疫反应,目前关于强弱IBRV毒株感染宿主细胞后的差异蛋白质组学研究尚未报道。本研究使用基于双向电泳与MALDI-TOF/MS的蛋白质组学技术,对比分析了MDBK细胞感染IBRV强毒株LN01/08与弱毒株LNM前后蛋白质组变化,共鉴定了8个差异蛋白。结果显示,丙酮酸激酶(PKM2)、肌切蛋白(SCIN)、转化生长因子(TGFBR1)及热应激蛋白90(Hsp90)在IBRV LN01/08株与IBRV LNM株感染组中表达量发生显著差异,其中PKM2和TGFBR1在IBRV LN01/08株组中高表达,Hsp90在IBRV LNM株感染组和MDBK细胞对照组中高表达,在IBRV LN01/08感染组中无表达。     

球虫抗药性分子生物学检测技术的建立

选择在敏感虫株中沉默、抗药虫株中表达的特异序列AGD5设计检测引物，采用RT—PCR方法。以总RNA反转录的cDNA为模板，RT—PCR方法能够鉴别马杜霉素抗药虫株和3株马杜霉素敏感虫株（2株对所有药物敏感的不同地理株，1株地克珠利抗药性虫株对马杜霉素敏感），此鉴定结果与鸡体试验的结果一致，说明敏感虫株和抗药虫株在该序列上的差异发生在转录水平。而以卵囊总DNA为模板的PCR方法不能鉴别敏感和马杜霉素抗药性虫株。     

A strain of Haemonchus contortus resistant to thiophanate

The occurrence of a field strain of Haemonchus contortus resistant to thiophanate is reported for the first time in New Zealand. In a controlled anthelmintic trial with experimentally infected animals, thiophanate at 50-100 mg/kg had no appreciable effect on the Haemonchus burden. Albendazole reduced faecal strongylate egg counts by 95% in animals with naturally acquired 59 infections.     

Muscle fibers of pigs sensitive to halothane and resistant to it

The histological and histochemical structure of m. longissimus thoracis, m. semimembranosus, m. triceps brachii-caput longum and m. rectus femoris was compared in pigs with a positive and negative reaction to halothane treatment. As found, the pigs affected by the malignant hyperthermia syndrome have thicker muscle fibres in the studied muscles. In the course of growth, the muscles of these animals have a larger proportion of red fibres (SO), but it is already at the age of 170 days (weight 100 kg) that light fibres prevail. The relative volume of the FG fibres is larger by 1-5%, as compared with the healthy animals. A higher number of pathologically changed fibres occurs in the pigs sensitive to halothane. The histological picture is individually variable; therefore the histological and histochemical methods cannot be considered as objective in view of MHS diagnosis. The general weakening of the constitution of the pigs is discussed as a possible predisposition factor underlying the development of various health disorders.     

Nested PCR检测微量隐孢子虫卵囊

根据隐孢子虫18SrDNA序列，设计出隐孢子虫属和鼠隐孢子虫种的特异性引物，进行PCR和Nested PCR反应，先后分剐扩增出1条540bp和1条250bp的条带。研究表明，NestedPCR具有高度的特异性和敏感性。应用NestedPCR可检测1～10个鼠隐孢子虫卵囊，其敏感性是饱和蔗糖漂浮法的10^5倍以上。     

Shedding of Oocysts in Piglets Experimentally Infected with Isospora suis

Christensen, S. AA. Henriksen: Shedding of oocysts in piglets experimentally infected with Isospora suis. Acta vet scand., 1994, 35, 165-172.–Forty-seven piglets were inoculated with doses of 100 to 50,000 sporulated oocysts of Isospora suis. After 5-7 days oocysts were found in faeces. The patent period extended from 8 to 16 days. The shedding of oocysts showed a cyclic pattern with 2-3 peaks separated by intervals of approximately 5 days. Subpatent periods were often seen between the peaks.The level of oocyst shedding during the initial days of the patent period reflected, to some extent, the inoculation dose. However, a maximum of OPG at the 100,000 level was observed among one or more piglets from all groups, regardless of the inoculation dose. Among the majority of piglets inoculated with more than 100 oocysts, the highest OPG-figures were observed in the first peak of the cyclic pattern. Unlike this, the maximum of OPG was observed in the second peak of the cycle among 6 of the 7 piglets inoculated with 100 oocysts only. The triphasic pattern was most pronounced in the low dosed group.The marked upscaling of oocyst production, as particularly registered in the low dosed groups, seams to explain at least part of the problems met under practical conditions, when trying to eliminate the transmission of oocysts between successive litters in the farrowing boxes.The cyclic excretion pattern and an apparent absence of autoinfections may indicate that the development of I. suis in the host includes several oocyst producing generations descending from the same initial infection.The presence of subpatent periods can probably explain the marked variation in OPG, as they are often recorded when examining faecal samples from piglets, even when the samples are originating from the same litter.     

猪圆环病毒2型细胞毒(MNS株)的驯化及全基因组序列分析

为了解猪圆环病毒2型(porcine circovirus type 2,PCV2)与参考毒株之间在分子生物学水平上的差异以及病毒驯化过程中的遗传变异情况,将分离的猪圆环病毒2型MNS株在PK-15细胞上盲传35代,并对4个代次病毒全基因组进行测序与分析。间接免疫荧光试验结果表明,感染细胞的细胞核中可以观察到特异性绿色荧光。病毒传代驯化到第35代后,病毒对细胞的适应性显著提高,病毒含量最高可达107TCID50/m L。对4个代次接种病毒Z0、Z3、Z19、Z35进行全基因组测序,结果表明,4代次细胞毒与PCV2参考毒株之间的全基因组序列同源性为93.9%~96.3%,与参考株af55394(PCV2b)核苷酸同源性较高。4代次细胞毒之间全基因组序列同源性为99.7%~99.9%,通过分析PCV2全基因组中碱基突变结果,发现各代次细胞毒与参考毒株之间存在19处点突变,16处点突变发生在ORF1中,3处发生在ORF2中。其中,ORF1 751~753 nt处发生基因颠换(TACGC→TTTTG)现象。本研究结果对今后进行PCV2复制机制、遗传变异以及开发高效价的病毒灭活疫苗等方面的研究奠定了基础。