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111.
Crohn’s disease and ulcerative colitis in humans and paratuberculosis in domestic and wild ruminants can be defined as chronic regional intestinal inflammatory diseases (CRIID). This review is a literature overview on these diseases in humans, non-human primates, dogs, cats, rabbits, equids and ruminants with a focus on pathological and microbiological features aimed identifying common characteristics that could lead to a unified pathological classification for a better understanding of their mechanisms and causes. The result is a framework of inflammatory forms throughout the different species indicative of common mechanisms of the slow infection type characterized by a time course varying from weeks to months or even years, and where the inflammatory component would be more prominent in the intestinal interphase between host and environment and be morphologically characterized by an infiltrate ranging from lymphoplasmacytic to histiocytic. This should provide new insights for causation demonstration and therapeutic approaches in human IBD.  相似文献   
112.
In this paper,a 1,860 bp sequence in IRs region of duck enteritis virus(DEV) was amplified by single oligonucleotide nested PCR with a single primer designed according to partial sequence of US1 and then a pair of primers designed according to the 3' UTR of US8 gene and 5' end of the new getting sequence were used to amplify a 2,426 bp sequence toward the TRs region.Sequence analysis revealed that the both sequences contained an identical 990 bp open reading frame of DEV US1 gene.The two ORFs were in opposi...  相似文献   
113.
The ultrasonographic appearance of the gastrointestinal tract of puppies suffering from parvoviral enteritis was characterized. Forty puppies between 6 and 24 weeks of age with confirmed canine parvoviral enteritis were examined ultrasonographically within 24 h of admission. Sonographic findings included fluid‐filled small intestines in 92.5% of subjects, and stomach and colon in 80% and 62.5% of subjects, respectively. Generalized atony was present in 30 subjects and weak peristaltic contractions indicative of functional ileus observed in the remaining 10 subjects. The duodenal and jejunal mucosal layer thicknesses were significantly reduced when compared with normal puppies with mean duodenal mucosal layer measuring 1.7 mm and jejunal mucosal layer 1.0 mm. Additionally, a mucosal layer with diffuse hyperechoic speckles was seen in the duodenum (15% of subjects) and the jejunum (50% of subjects). The luminal surface of the duodenal mucosa was irregular in 22.5% of subjects and the jejunal mucosa in 42.5% of subjects. In all of these subjects, changes were accompanied by generalized indistinct wall layering. Small intestinal corrugations were seen within the duodenum in 35% of subjects and within the jejunum in 7.5%. A mild amount of anechoic free peritoneal fluid was observed in 26 subjects and was considered within normal limits and a moderate amount of anechoic free peritoneal fluid was observed in six subjects. The jejunal lymph node size was within normal limits. None of the above changes are pathognomonic for canine parvoviral enteritis but finding them in combination is highly suggestive.  相似文献   
114.
水貂肠炎病毒B株全基因克隆与序列分析   总被引:2,自引:0,他引:2  
将水貂肠炎病毒基因组分4个重叠片段进行PCR扩增,并将产物克隆到pMD18-T载体中,测定基因组近全长序列。其中编码水貂肠炎病毒非结构蛋白基因(NS1基因)全长为2 007 bp,编码668个氨基酸;编码结构蛋白基因(VP2基因)全长为1 755 bp,编码584个氨基酸。序列分析结果表明:水貂肠炎病毒B株与犬细小病毒、猫泛白细胞减少症病毒NS1序列之间的核苷酸和氨基酸同源性分别为98.8%~99.2%和98.8%~99.2%,与其他细小病毒毒株VP2序列之间的核苷酸和氨基酸同源性分别为98.5%~99.8%和97.8%~99.5%,与MEVantigenic type 2株在亲缘上有着最密切关系。  相似文献   
115.
A novel toxin, NetB, has recently been identified in virulent avian Clostridium perfringens isolates and shown to be an essential virulence factor in a clinical necrotic enteritis isolate. To assess whether NetB is more generally associated with avian necrotic enteritis isolates we have screened a range of C. perfringens strains from geographically diverse locations for both the presence and expression of the netB gene. Forty-four isolates were derived from necrotic enteritis disease cases from Australia, Belgium, Denmark and Canada and 55 isolates from healthy chickens from Australia and Belgium. The majority of strains isolated from necrotic enteritis-affected birds were netB positive (70%) and there was an absolute correlation between the presence of netB and in vitro expression of the NetB protein. Only two of the C. perfringens isolates from healthy chickens carried netB. Sequencing of the netB gene from 23 positive isolates showed that NetB is highly conserved, with only one predicted amino acid (A168T) difference, in six isolates, compared to the published sequence. This change did not alter the in vitro activity of the NetB toxin. The gene encoding the recently discovered TpeL toxin was also screened using PCR and only found in a small proportion of NetB-positive isolates from diseased birds. A selection of NetB-negative isolates, originating from diseased birds, was unable to cause disease in a necrotic enteritis induction model. This study provides further evidence that NetB is important in pathogenesis and advances our current understanding of C. perfringens virulence factors in avian necrotic enteritis.  相似文献   
116.
Canine parvovirus 2 (CPV-2) causes a highly contagious and often fatal disease in dogs. Since its sudden emergence in the early 1970s, CPV-2 has been evolving through the generation of novel genetic and antigenic variants (CPV-2a/b/c) that are unevenly distributed throughout the world. In the present study we have examined 36 clinical cases of dogs suspected of CPV collected during year 2006. A fragment of the VP2 gene of the virus was analyzed using polymerase chain reaction (PCR), restriction endonuclease (RE) and DNA sequence analysis. Out of the 36 samples analyzed, 16 were found positive for CPV-2a/2b by conventional PCR. DNA sequencing was done for 6 PCR positive samples, out of which three were characterized as CPV-2c, indicating that this CPV type 2c is currently circulating in India.  相似文献   
117.
Solvent‐extracted soybean meal (SESBM) has been reported to cause subacute enteritis in certain fish species. Two 34‐day experiments investigated the effects of SESBM and soy protein concentrate (SPC) on the intestinal mucus layer and development of subacute enteritis in the hindgut of yellowtail kingfish (Seriola lalandi) at 22 and 18 °C. Fish were fed increasing levels of SESBM (Exp. 1: 0 g kg?1, 100 g kg?1, 200 g kg?1, 300 g kg?1) and SPC (Exp. 2: 0 g kg?1, 200 g kg?1, 300 g kg?1, 400 g kg?1). No visual signs of inflammation in the hindgut were observed in either experiment. However, increasing dietary SESBM significantly reduced mucus layer thickness. Neutral and acidic goblet cell mucin composition increased at 18 and 22 °C, respectively. A significant positive linear relationship was evident between goblet cell number and SESBM inclusion at 18 °C. SPC inclusion and water temperature had no significant effect on mucus layer thickness or mucin composition. However, at 18 °C, goblet cell numbers decreased with SPC inclusion. Results suggest the early stages of subacute enteritis may have been manifesting in SESBM fed fish. In the long term, mucus layer alterations associated with feeding SESBM may compromise fish health. Longer‐term studies should investigate the effects of feeding SESBM to yellowtail kingfish, particularly at suboptimal water temperatures.  相似文献   
118.
陈柳  余斌  倪征  华炯钢  叶伟成  云涛  张存 《中国农业科学》2016,49(14):2813-2821
【目的】鸭瘟和小鹅瘟是番鸭和鹅的两种重要传染病,鸭瘟最主要的防治措施是定期接种鸭瘟病毒减毒活疫苗。根据2012年国际病毒分类委员会(ICTV)的报告,DEV被归为疱疹病毒科的α疱疹病毒亚科马立克氏病毒属。疱疹病毒如伪狂犬病毒、马立克氏病毒、火鸡疱疹病毒等已广泛用于病毒活载体的研究,而近几年也有关于鸭瘟病毒(DEV)作为疫苗活载体的报道。为了为免疫防控鸭瘟和小鹅瘟提供新手段,本研究拟在鸭瘟病毒疫苗株感染性克隆的基础上,构建表达小鹅瘟病毒(GPV)主要免疫原蛋白VP2的重组病毒rDEV-VP2,并研究其生物学特性,进而探讨重组病毒rDEV-VP2作为防治DEV和GPV的二联重组活载体疫苗的可能性。【方法】将密码子优化的GPV VP2基因通过常规基因克隆的方法插入转移载体pEP-BGH-end,构建含有GPV VP2表达框pCMV-VP2-BGH-pA的重组表达质粒。在鸭瘟病毒(DEV)疫苗株细菌人工染色体克隆pDEV-EF1的基础上,通过“Red E/T”两步重组法将GPV VP2基因表达框插入到DEV US7和US8基因之间构建了突变体克隆pDEV-VP2。利用磷酸钙法转染鸡胚成纤维细胞(CEFs)拯救获得重组病毒rDEV-VP2和删除Bac质粒序列的rDEV-VP2-Cre,并对重组病毒细胞体外生长曲线、蚀斑大小和VP2蛋白表达情况进行测定。将rDEV-VP2接种番鸭,在不同时间采集血清,采用间接ELISA法检测血清中GPV VP2抗体产生情况。【结果】间接免疫荧光检测和Western blotting分析表明,外源蛋白VP2在CEFs细胞成功表达。病毒生长曲线和蚀斑大小测定结果显示,rDEV-VP2在CEFs细胞上的增殖滴度与亲本株相比无显著差异,表明外源基因VP2的插入不影响rDEV重组病毒的增殖。动物试验结果表明,7日龄雏番鸭接种rDEV-VP2可以诱导产生针对GPV VP2的抗体,免疫后3周抗体阳性率为50%(4/8)。【结论】本实验将小鹅瘟病毒的主要免疫原基因VP2插入到DEV疫苗株基因组的US7和US8基因间构建了表达该免疫原性基因的重组鸭瘟病毒细菌人工染色体,继而在鸡胚成纤维细胞(CEFs)上拯救获得了重组病毒rDEV-VP2,病毒细胞生长特性与亲本株基本一致,且能诱导鸭体产生GPV VP2特异性的抗体。该研究为研制DEV-GPV二联重组活载体疫苗奠定了基础。  相似文献   
119.
为研究地衣芽孢杆菌H2对坏死性肠炎肉鸡生长性能及肠道菌群的影响,选取240只1日龄科宝-500肉鸡,随机分为Ⅰ组(空白对照组)、Ⅱ组(造模组)、Ⅲ组(球虫+鱼粉组)和Ⅳ组(地衣芽孢杆菌防治组)。Ⅱ组、Ⅲ组和Ⅳ组从14日龄起饲喂添加30%鱼粉的日粮并于15日龄灌喂球虫,Ⅱ组和Ⅳ组18~20日龄连续灌喂产气荚膜梭菌(2.2×108 cfu/mL)1mL,其余各组灌喂同等剂量的生理盐水,试验期总共为22d。结果表明:坏死性肠炎的发生会显著降低肉鸡体增重升高料重比(P0.05),地衣芽孢杆菌的添加能提高坏死性肠炎肉鸡体增重。DGGE图谱聚类结果显示,肉鸡回肠内容物菌群主要聚为两簇,Ⅳ组和Ⅰ组聚为一簇,Ⅱ组和Ⅲ组聚为一簇,相似性为0.70。此外,与Ⅱ组相比,Ⅰ组和Ⅳ组回肠内容物中乳杆菌属数量显著增加(P0.05),Ⅰ组肠杆菌科数量显著降低(P0.05),Ⅳ组肠杆菌科数量降低且与Ⅰ组无显著差异(P0.05)。综上所述,在日粮中添加地衣芽孢杆菌能改善坏死性肠炎肉鸡生长性能,调节由坏死性肠炎导致的菌群失调。  相似文献   
120.
An epizootic incidence of intestinal adenocarcinomas was reported in brood fish of Atlantic salmon (Salmo salar L.) in 2009. The condition was associated with a specific diet inducing enteritis and morphological changes. Here, two field trials of fish up to slaughter size were initiated. In Trial 1, two different feed recipes were used. Feed I was predominantly based on marine ingredients, whereas plant ingredients were limited to soy protein concentrate and wheat. Feed II was lower in fishmeal and without soya protein, which was substituted with plant proteins from other sources. In Trial 2, a commercial feed (Feed III) was included. No macroscopic tumours were observed in 300 fish (Trial 1). At the end of both trials, samples from five different segments of the gastrointestinal tract of a total of 39 fish were investigated with morphological methods. Here, we show the presence of ectopic proliferating epithelial cells only occurring in inflamed intestine and predominantly in the second segment of the mid‐intestine. Presence of ectopic epithelial cells in submucosal inflammatory foci may indicate early stages in tumorigenesis, but other possibilities such as proliferative enteric disorders cannot be excluded. Together with inflammation, carcinogenesis should be a focus of investigation in future feed trials.  相似文献   
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