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1.
4型菌毛、毒素及蛋白酶在动物源气单胞菌的检测 总被引：1，自引：0，他引：1
将来源于鱼、猪、犬等９种动物的１８株气单胞菌分离株通过ＡＤ（氨苄青霉素－糊精）培养基纯化。另以大肠杆菌束状菌毛相关（ｂｆｐ－ｒｅｌａｔｅｄ）基因的ＰＣＲ引物对ＥＢ１（ＧＡＴＴＧＡＡＴＣＴＧＣＡＡＴＧＧＴＧＣ）—ＥＢ２（ＧＧＡＴＴＡＣＴＧＴＣＣＴＣＡＣＡＴＡＴ）扩增,用ｄｉｇｏｘｉｎｇｅｎｉｎ－１１－ｄＵＴＰ标记,构建核酸探针,作斑点杂交试验,用以检测上述气单胞菌菌株的４型菌毛,同时以溶血试验检测其毒素,用脱脂奶溶蛋白圈试验检测其蛋白酶。结果显示,在１８个菌株中,４型菌毛、毒素和蛋白酶均为阳性者为１０株（５５．６％）;３项指标均无肯定的阳性结果者４株,两者合计共１４株,占检测总数约８０％（１４／１８）,提示这３种毒力因子存在较高的相关性。所有鱼源株（５株）三项指标皆为阳性;４株猪分离株三项指标均为阳性者占一半;其它动物分离株检测结果无明显规律性 相似文献
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旨在探究调控藏羊皮肤内立毛肌发生的分子机制，挖掘影响立毛肌发生的关键基因。本研究采集了30个75~110日龄健康情况良好的藏羊胚胎，收集背部皮肤组织，制作石蜡组织切片，利用HE染色观察背部皮肤内不同日龄立毛肌的形态学变化特征，推测出立毛肌发生的关键时期为胚龄75~85天（E75~E85）；分别挑选胚龄大约在75和85天各3个背部皮肤组织样品，分样品提取RNA，利用Illumina Hiseq平台进行转录组测序，对测序数据进行质控、过滤、比对，筛选得到差异表达基因，并对差异基因进行功能注释、富集分析、蛋白网络互作和RT-qPCR验证，挖掘调控立毛肌早期发育的关键候选基因。测序结果共得到1 159个差异表达的基因（P<0.05），其中900个基因上调，259个基因下调。随机选择6个差异表达的基因进行RT-qPCR验证，表达趋势与转录组测序结果一致，表明测序结果可靠。通过对差异基因进行GO功能注释和KEGG富集分析，筛选到与立毛肌发育相关的5个生物学过程条目和5个信号通路共47个非冗余基因（如BAMBI、TNNI3、HOXA9等）。本研究表明，藏羊立毛肌开始发育的关键时期约为E75~E85天，该时期内SPP1、BAMBI、TNNI3、HOXA9、SOX15可能为影响藏羊立毛肌发生的关键候选基因。 相似文献
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Use of enzyme-linked immunosorbent assay for detection of K88 pili in fecal specimens from swine 总被引：4，自引：0，他引：4
Enterotoxigenic Escherichia coli are important in neonatal pig diarrhea. To be pathogenic, E coli must possess the ability to produce toxin and adherence structures called pili. An enzyme-linked immunosorbent assay was used to detect K88 pili in feces of swine. Results were compared with standard isolation and identification techniques. Isolates were tested for labile toxin production by the Y-1 mouse adrenal gland test and presence of pili by the enzyme-linked immunosorbent assay test. The ability to detect K88 pili in feces correlated with the isolation of labile toxin-positive, K88-positive E coli. 相似文献
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鸡大肠杆菌多价1型菌毛亚单位疫苗在鸡体内的免疫原性研究 总被引：4，自引：0，他引：4
用1日龄雏鸡免疫评价了鸡大肠杆菌多价1型菌毛油乳剂苗在鸡体内的免疫原性。用含1型菌毛的3个不同血清型（O1、O78及O88）菌株,大容量培养后提取菌毛制备多价菌毛油乳剂苗。接种多价菌毛油乳剂苗的鸡用同源菌株攻毒后出现10％～11．2％的死亡率,阳性对照组鸡攻毒后出现70％～80％的死亡率;用异源菌株（O36）攻毒后,免疫鸡出现33．3％的死亡率,而未免疫阳性对照组鸡死亡率达70％。免疫鸡在气囊,心包及肝脏的病变非常轻微,且攻毒后非免疫鸡能更有效地清除侵入气囊的大肠杆菌。 相似文献
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鸡致病性大肠杆菌I型菌毛的研究进展 总被引：3，自引：0，他引：3
鸣致病性大肠杆菌I型菌毛是鸡大肠杆菌病的重要致病因子。本文对其生物学特性、在感染中的作用、分子生物学等8个不同方面的研究进展做了综述。 相似文献
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Pili of Bordetella avium: expression, characterization, and role in in vitro adherence 总被引：2，自引：0，他引：2
Electron microscopy revealed pili on all isolates of Bordetella avium and B. avium-like bacteria examined. Trypticase soy broth (TSB) and 2% peptone agar were the best media for promoting pilus expression. Cultures grown at 37 or 42 C had similar pilus production, whereas cultures grown at 18 C produced few or no pili. Pilus expression of the Art Vax strain was best when that strain was grown in TSB, but the strain yielded fewer pili than B. avium and B. avium-like isolates grown under the same cultural conditions. B. avium pili had a diameter of 2.0 nm, ranged in length from 370 nm to 1500 nm, and had a protein subunit molecular mass of about 13,100 daltons. Purified pili from B. avium did not hemagglutinate guinea pig erythrocytes, and a 1:20 dilution of hyperimmune antisera against B. avium pili did not block the hemagglutinating activity of whole-cell preparations of B. avium. In the indirect immunofluorescence test, B. avium isolates and the Art Vax strain adhered to the tracheal explants of turkeys, but B. avium-like isolates did not. Purified pili from B. avium adhered to the surface of the mucosal lining of the tracheal explants, and hyperimmune antisera against B. avium pili blocked the in vitro adherence of whole-cell preparations of B. avium. It was concluded that pili of B. avium are involved in the in vitro attachment of that bacterium to the mucosal surface of turkey tracheal explants. 相似文献
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R E Isaacson 《Avian diseases》1986,30(1):28-36
A vaccine was prepared using recombinant DNA techniques to prevent fatal enterotoxigenic Escherichia coli diarrhea in swine. The product, which is a subunit vaccine, was prepared by mechanical and chemical removal of pilus adhesins from the surface of genetically engineered strains of E. coli. The vaccine contains the pilus adhesins K88, K99, and 987P plus an adjuvant. The genes responsible for production of K88 and K99 were separately cloned into the multicopy vector pBR322. K88 was found to be encoded on a 7.6-kilobase HindIII-EcoRI fragment, and K99 was found to be encoded on a 7.15-kilobase BamHI fragment. Strains containing the recombinant plasmid for K99 produced up to ten times more K99 than strains containing the wild-type plasmid. Vaccination of pregnant pigs with the vaccine led to production of pilus-adhesin-specific antibodies that were transferred to the piglets in colostrum and milk. Pilus-adhesin-specific antibodies neutralized the adhesiveness of the pili on enterotoxigenic E. coli, thus preventing attachment, colonization, and disease. Mortality of pigs in litters from vaccinated pigs due to experimentally induced enterotoxigenic E. coli diarrhea was reduced 10-to-20-fold (depending upon the challenge strain), and the incidence, severity, and duration of diarrhea were also reduced. 相似文献
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提取鸡致病性大肠杆菌分离株O1、O2和O78的基因组DNA作模板,用TD-PCR技术从其中分别扩增出0.55 KB的I型菌毛结构基因(piliA).将扩增得到的piliA基因片段,用TA克隆的方法分别克隆进pGEM-T栽体中,转化至受体菌JM109中,用Amp/IPTG/X-gal琼脂平板蓝白菌落筛选法,得到舍阳性重组子的菌株,提取质粒用PstI单酶切及NcoI和PstI双酶切鉴定,结果证实,所构建的克隆质粒中均含有相应piliA基因.经DNA序列分析,其结构基因阅读框架大小为549 bp,但其中O1菌株Ⅰ型菌毛基因在第72位发生突变,有6个碱基插入.经DNAStar核酸分析软件分析,3个基因同源性为89.9%～92.0%. 相似文献
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Adherence of Moraxella bovis to cell cultures of bovine origin 总被引：5，自引：0，他引：5
The adherence of five strains of Moraxella bovis to cell cultures was investigated. M bovis adhered to cultures of bovine corneal epithelial and Madin-Darby bovine kidney cells but not to cell types of non-bovine origin. Both piliated and unpiliated strains adhered but piliated strains adhered to a greater extent than unpiliated strains. Antiserum against pili of one strain inhibited adherence of piliated strains but caused only slight inhibition of adherence to the unpiliated strains. Treatment of bacteria with magnesium chloride caused detachment of pili from the bacterial cell and markedly inhibited adherence of piliated strains but caused only slight inhibition of adherence by the unpiliated strains. The results suggested that adhesion of piliated strains to cell cultures was mediated via pili but that adhesins other than pili may be involved in the attachment of unpiliated strains of M bovis to cells. 相似文献
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Antigenic Detection of Human Strain of Influenza Virus A (H3N2) in Swine Populations at Three Locations in Nigeria and Ghana during the Dry Early Months of 2014 
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下载免费PDF全文 Since the first detection of human H3N2 influenza virus in Taiwanese pigs in 1970, infection of pigs with wholly human viruses has been known to occur in other parts of the world. These viruses, referred to as human‐like H3N2 viruses, have been known to cause clinical and subclinical infections of swine populations. Due to the paucity and complete unavailability of information on transmission of influenza viruses from other species, especially humans, to swine in Nigeria and Ghana, respectively, this study was designed to investigate the presence and prevalence of a human strain of influenza A (H3N2) in swine populations at three locations in two cities within these two West African countries in January and February, 2014. Using stratified random technique, nasal swab specimens were collected from seventy‐five (75) pigs at two locations in Ibadan, Nigeria and from fifty (50) pigs in Kumasi, Ghana. These specimens were tested directly by a sensitive Quantitative Solid Phase Antigen‐detection Sandwich ELISA using anti‐A/Brisbane/10/2007 haemagglutinin monoclonal antibody. Influenza virus A/Brisbane/10/2007 (H3N2) was detected among pigs at the three study locations, with an aggregate prevalence of 4.0% for the two locations in Ibadan, Nigeria and also 4.0% for Kumasi, Ghana. Transmission of influenza viruses from other species to swine portends serious sinister prospects for genetic reassortment and evolvement of novel viruses. We therefore recommend that further studies should be carried out to investigate the presence of other circulating human and avian influenza viruses in swine populations in West Africa and also determine the extent of genetic reassortment of strains circulating among these pigs. This would provide an early warning system for detection of novel influenza viruses, which could have pandemic potentials. 相似文献
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W.Q. Alali H.M. Scott K.L. Christian V.R. Fajt R.B. Harvey D.B. Lawhorn 《Preventive veterinary medicine》2009,90(3-4):160-167
The objective of this longitudinal ecological study was to examine the relationship between the prevalence of antibiotic-resistant (AR) commensal Escherichia coli isolates from both monthly human wastewater and composite swine fecal samples and the concurrent aggregated monthly antibiotic use recorded within each host species in multi-site vertically integrated swine and human populations. In addition, human vocation (swine worker versus non-swine worker), swine production group, and season were examined as potential confounding variables. Human and swine E. coli isolates (n = 2469 human and 2310 swine, respectively) were tested for antimicrobial susceptibility using a commercial broth microdilution system. In the human population, among swine workers the relative odds of tetracycline resistance were increased significantly for tetracycline (class) drug use at the third quartile and above of mean monthly dosage (MMD) (OR = 1.8) as compared to the referent category (non-use). The relative odds of ciprofloxacin resistance were significantly increased for ciprofloxacin use in non-swine workers (OR = 5.5) as compared to the referent (non-use). The relative odds of tetracycline resistance were increased significantly for chlortetracycline use in medicated feed for the upper tertile of MMD category (OR = 2.9) as compared to the referent category (no use) across all swine production groups. While high variability among seasonal samples over the 3-year period was observed, no common seasonal trends relating to antibiotic use and prevalence of resistance over the 3-year period were apparent. The overall effects of concurrent human and swine antibiotic use on AR E. coli levels were inconsistent and modest in this study. 相似文献
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Genetic analysis of human and swine influenza A viruses isolated in Northern Italy during 2010–2015 下载免费PDF全文
下载免费PDF全文 C. Chiapponi E. Ebranati E. Pariani S. Faccini A. Luppi L. Baioni R. Manfredi V. Carta M. Merenda P. Affanni M. E. Colucci L. Veronesi G. Zehender E. Foni 《Zoonoses and public health》2018,65(1):114-123
Influenza A virus (IAV) infection in swine plays an important role in the ecology of influenza viruses. The emergence of new IAVs comes through different mechanisms, with the genetic reassortment of genes between influenza viruses, also originating from different species, being common. We performed a genetic analysis on 179 IAV isolates from humans (n. 75) and pigs (n. 104) collected in Northern Italy between 2010 and 2015, to monitor the genetic exchange between human and swine IAVs. No cases of human infection with swine strains were noticed, but direct infections of swine with H1N1pdm09 strains were detected. Moreover, we pointed out a continuous circulation of H1N1pdm09 strains in swine populations evidenced by the introduction of internal genes of this subtype. These events contribute to generating new viral variants—possibly endowed with pandemic potential—and emphasize the importance of continuous surveillance at both animal and human level. 相似文献
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Pedro Smith Livio Zurita Francisco Canale Arturo Ferreira Haroldo Toro 《Veterinary microbiology》1994,40(3-4):387-392
An ELISA to detect circulating antibodies against K99 pili, a major attachment factor to intestinal epithelial cells of Escherichia coli in calves, was performed. Two methods of K99 pili purification were attempted. Best results in terms of purity of the K99 antigen were achieved following the method described by Karkhanis and Bhogal (1986). This procedure included a heat shock at 65°C during 25 min to release the pili and ultracentrifugation steps to purify the antigen. SDS-PAGE showed an 18 KDa major band, identified as the K99 pilus antigen after immunoblotting against reference antisera. The purified K99 antigen was then adsorbed to the ELISA microplates. High optical density was obtained in the ELISA using a pool of sera from immunized cows. No differences in antibody levels (P ≥ 0.05) could be detected between clinically healthy calves and those showing diarrhoea. 相似文献
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Prevalence of K88, K99, and 987P pili of Escherichia coli in neonatal pigs with enteric colibacillosis 总被引：1，自引：0，他引：1
One hundred nineteen live neonatal pigs with diarrhea less than or equal to 2 weeks old were euthanatized, and frozen sections of their ilea were submitted to an indirect fluorescent antibody technique to identify K88, K99, and 987P pili (also referred to as F-4, F-5, and F-6 pili, respectively) in Escherichia coli. Ten-centimeter ileal sections were used to determine numbers of lactose-fermenting bacteria. Of 52 pigs in which E coli pili were found, 14 had K88 (27%), 23 had K99 (44%), 13 had 987P (25%), and 2 had K88 and K99 simultaneously (4%). Numbers of lactose-fermenting bacteria were significantly (P less than or equal to 0.05) higher in pigs with piliated E coli than in pigs without piliated E coli. Results of this study indicated that piliated E coli are a major cause of enteric disease in neonatal swine in Michigan, and that in pigs less than or equal to 2 weeks of age, K99 was the most frequently encountered pilus antigen. 相似文献
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Hudgens E Tompkins D Boyd P Lunney JK Horohov D Baldwin CL 《Veterinary immunology and immunopathology》2011,141(3-4):317-321
This report describes the cloning and characterization of expressed gene sequences of bovine, equine, and swine CXCL9 from RNA obtained from peripheral blood mononuclear cells (PBMC) and other tissues. The bovine coding region was 378 nucleotides in length, while the equine and swine coding regions were 381 nucleotides. Mapping showed that all three sequences were coded for in four exons in the genome, as are the human and mouse genes. The bovine, equine, and swine coding regions shared 83%, 86%, and 84% homology with human CXCL9, respectively, and all three were 74% homologous with mouse CXCL9. Cladogram comparison of the nucleotide sequences of CXCL9 showed that the bovine, equine and swine sequences were more closely related to one another than to either the human or the mouse sequences. However, the human sequence was more closely related to them than it was to the mouse sequence. These relationships were preserved when the deduced amino acid sequences were evaluated and all sequences showed conservation of the characteristic four cysteines. This work sets the stage for further work with these molecules; an integral goal of the U.S. Veterinary Immune Reagent Network is to develop reagents for investigating diseases in livestock species, poultry, and fish. 相似文献
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鸡传染性支气管炎病毒血凝谱的研究 总被引：1，自引：0，他引：1
用家兔A型魏氏梭菌培养液处理的6株鸡传染性支气管炎病毒,以方阵试验分别与人O型红细胞及羊、猪、兔、鸡、鸭、鹌鹑、麻雀、小鼠等8种动物的红细胞作血凝试验,结果证明,鸡传染性支气管炎病毒H_(120)株和M_(41)株均能凝集人O型以及羊、猪、兔、鸡、鸭、鹌鹑、小鼠的红细胞,而不能凝集麻雀的红细胞;GIBV株和Connecticut株能凝集人O型以及免、鸡、鹌鹑、麻雀的红细胞,而不能凝集猪、羊、鸭、小鼠的红细胞;Gray株能凝集兔、鸡、鹤鹑的红细胞,不能凝集人O型以及猪、羊、鸭、麻雀、小鼠的红细胞;而经家兔A型魏氏梭菌培养液处理的T株和未经处理的6株病毒对人O型以及8种动物的红细胞都没有凝集性。试验还证明,M_(41)株和H_(120)株对人O型及8种动物的血凝活性水平有差异。 相似文献