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1.
Q fever is zoonotic disease caused by Coxiella burnetii. Ruminants are the main reservoir of this pathogen, which is often asymptomatic but lead to abortion. This study aims to survey the seroprevalence and risk factors of this zoonose among ruminants in Kurdistan province, the west of Iran. 480 blood samples were collected from ruminants including sheep, goats and cows, each 160 samples, in the age groups of <1, ≥1−3, >3−5 year with and without the history of abortion in two groups border and non-border cities in Kurdistan province. Serums were tested by use of indirect ELISA to determine specific antibodies against C. burnetii. The results indicate the seroprevalence of 46.6 % for Q fever. Seroprevalence in sheep, goats and cows were 28.58 % (n = 64), 45.53 % (n = 102) and 25.89 % (n = 58), respectively. Seroprevalence is significantly higher in animals with abortion than in those without such history (P < 0.05). The seroprevalence in the border cities has been significantly higher than other geographical areas (P < 0.05). Seroprevalence had no significant correlation with animal age (P> 0.05). This study is the first seroepidemiological study done on Q fever in ruminants of Kurdistan province, Iran. The results indicate the high seroprevalence of Coxiella burnetii in the area under the study. Therefore, doing an epidemiologically study aimed at isolating C. brunetii in the human population of Kurdistan province is recommended, so that the epidemiological aspect of this pathogen in the people of Kurdistan province be clarified and subsequently disease control and prevention programs be applied. 相似文献
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Tanapon Soonthonsrima Pradit Wangman Parin Chaivisuthangkura Chalinan Pengsuk Paisarn Sithigorngul Siwaporn Longyant 《Aquaculture Research》2019,50(1):277-283
The simple immunoprecipitation method was used to isolate tilapia immunoglobulin (Ig) for immunization in order to produce monoclonal antibodies (MAbs) specific to tilapia Ig. First, the tilapia antiserum against bovine serum albumin (BSA) was prepared by peritoneal injection of BSA into tilapia, and the tilapia anti‐BSA antiserum was used to precipitate BSA to form the Ig/BSA immune complex. The Ig/BSA immune complex was then injected into Swiss mice for hybridoma production. After fusion, three hybridoma clones producing MAbs specific to the tilapia antibody were selected by dot blot and Western blot. All MAbs (101A, 59G, and 11A) were bound specifically to the heavy chain of immunoglobulin M (IgM). The MAbs 101A and 59G demonstrated twofold higher affinity than MAb 11A and the commercialized antibody. However, MAbs 11A could also bind to the heavy chain of IgM in Asian seabass, Lates calcarifer, as well. These MAbs can be used to monitor the immune responses of individual fish by indirect ELISA upon exposure to various antigens. 相似文献
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As laid down by the Codex Alimentarius, products bearing a gluten-free label must not contain gluten levels above 20 mg/kg to be safe for consumption by celiac disease patients. Analytical methods to detect gluten from wheat, rye and barley need to be sufficiently sensitive, specific, suitable for routine analyses and validated by collaborative studies. With continuous progress in the field of gluten analysis, the aim of this paper is to provide an up-to-date overview of legislation regarding gluten-free products worldwide, as well as immunochemical, proteomics-based, genomics-based and other methods designed to analyse gluten traces. While ELISA test kits and PCR are still most widely used in quality control, liquid chromatography tandem mass spectrometry (LC-MS/MS) is gaining more and more importance by providing unprecedented insights into gluten. Several other methods such as immunosensors, other sensors and microarrays are being developed. The pro's and con's of the different methods are discussed as well as the remaining challenges, including the need for improved extraction procedures, comprehensive reference materials and independent reference methods. 相似文献
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为建立评价O型口蹄疫病毒(FMDV)疫苗免疫水平的方法,本研究以单克隆抗体(MAb)3D9为捕获抗体,以HRP标记的MAb 8E8作为检测MAb,经过条件优化建立了基于MAb的检测O型FMDV抗体的固相竞争ELISA(SPCE)方法。对该方法进行了特异性、敏感性、重复性试验。结果显示,MAb 3D9的最佳稀释度为1:25 000,灭活O型FMDV抗原的最佳稀释浓度为1:3,HRP标记的MAb 8E8的最佳稀释度为15 000,当血清1:32稀释时,检测的临界值确定为45%。该方法分别检测A型FMDV抗体阳性参考血清以及牛冠状病毒、牛轮状病毒以及猪繁殖与呼吸障碍综合征病毒、猪圆环病毒、猪瘟病毒的标准阳性血清,检测结果均为阴性,未出现交叉反应。经检测,当阳性标准血清的抗体稀释度在1:512时,该方法仍具有较好的敏感性;批内和批间重复性试验的变异系数均小于10%,表明其重复性较好。并将该方法与液相阻断ELISA(LPBE)方法和病毒中和试验(VNT)的相关性进行了比较,结果显示该方法与LPBE和VNT的相关性分别为0.896和0.923。本研究为国内评价O型FMDV疫苗免疫水平建立了一种新的方法。 相似文献
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本文介绍了近些年来饲料中沙门氏菌的检测方法,并提出了预防饲料中沙门氏菌污染的措施,具体包括饲料原料选择、生产加工过程的控制以及包装、运输、储存、使用过程的控制等方面内容,以期为饲料安全生产提供参考。 相似文献
7.
为了研究植物内源褪黑素与植物抗性的关系,以4叶1心的番茄幼苗为试验材料,采用酶联免疫吸附测定(ELISA)法测定正常番茄、鱼腥草提取液和灰霉菌侵染后的番茄茎叶中的褪黑素含量。结果表明:番茄叶片和茎的褪黑素含量分别为14.53、2.80 ng/g,二者之间差异极显著,叶片的褪黑素含量是茎的5.19倍;经鱼腥草提取液预处理和灰霉菌侵染后,番茄叶片的褪黑素含量显著增加,鱼腥草提取液预处理有助于减轻番茄叶片上的灰霉病发病症状,但并不依赖于叶片内源褪黑素含量的增加。可以检出的番茄茎叶中的褪黑素含量高于2.60 ng/g,就灵敏度而言,ELISA法完全可以用来检测番茄的组织器官的褪黑素含量。 相似文献
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Investigation of the leptin levels in the blood serum of Cyprinus carpio (Linnaeus, 1758) and Capoeta trutta (Heckel, 1843) 下载免费PDF全文
Leptin is a peptide hormone secreted by adipose tissues in the various teleost fish and vertebrates. Leptin has been suggested to have an important role in a range physiological function, including regulation of food intake, reproduction, immune function, energy expenditure, lipid and carbohydrate metabolism. In this study, leptin levels in the blood serum of Cyprinus carpio and Capoeta trutta were determined. Then the results were compared between two species and between sexes of each species. In addition, leptin levels were also compared with the body weight and length of both C. carpio and C. trutta. Leptin level was analysed using available enzyme‐linked immunoassay (ELISA) kit (Rat leptin ELISA kit, catalog no: SK00050‐08). Leptin levels showed no significant difference (p > 0.05) that in relation to between two species and between sexes of each species. It has been shown that not significantly correlated when examined correlations between the leptin level in blood serum and body weight (r = 0.192, p = 0.380) or length (r = 0.102, p = 0.644) of C. carpio. Similarly, the correlations between leptin level in blood serum and body weight (r = 0.021, p = 0.959) or length (r = 0.123, p = 0.595) of C. trutta were also not significant. 相似文献