短裸甲藻毒素单克隆抗体的制备及其鉴定

采用混合酸酐法将短裸甲藻毒素(brevetoxins,BTX)分别与卵清蛋白(OVA)和牛血清蛋白(BSA)偶联制备人工抗原。以BTX-BSA作为免疫抗原免疫BALB/c小鼠,通过细胞融合-ELISA筛选抗短裸甲藻毒素的单克隆抗体,并对其特异性和灵敏性进行了鉴定。结果获得了1株可分泌短裸甲藻毒素单克隆抗体的杂交瘤细胞株3B4,该株杂交瘤细胞腹水抗体效价达10-5,与其他类似物没有交叉反应。该抗体为建立短裸甲藻毒素免疫学检测方法奠定了基础。     

饲料中赭曲霉毒素的危害和监控

赭曲霉毒素A(OchratoxinA ,OA)是由曲霉菌属和青霉菌属几种菌产生的次生代谢产物,动物试验表明对肾脏、肝脏等具有较强的毒性。赭曲霉毒素广泛分布于饲料及饲料原料中,被摄食后累积在畜、禽体内,通过食物链对人类健康构成威胁。许多国家对其制定了最高允许量,并建立了监控检测体系。随着我国加入WTO ,建立自己的质量标准以监控饲料中赭曲霉毒素A是必要的。1　危害1 1　赭曲霉毒素A的毒性　赭曲霉毒素包含了7种结构类似的化合物,其中以赭曲霉毒素A的毒性最强。赭曲霉毒素A具有烈性的肾脏毒和肝脏毒,在自然界中低浓度存在时主要侵袭肾脏…     

产气荚膜梭菌ε毒素受体研究进展

产气荚膜梭菌是产生多种毒素的厌氧菌,在人类和动物中引起多种疾病。其中一种毒素ε毒素(ETX)能诱导山羊、绵羊和牛的致命肠道疾病。ETX属于成孔毒素,含有3个不同的结构域,通过蛋白水解活化及脂筏相关蛋白在细胞表面形成寡聚孔。ETX被美国疾病控制和预防中心(CDC)列为B类生物恐怖战剂,其毒力仅次于肉毒毒素和破伤风神经毒素。ETX能与其靶细胞膜受体特异性结合,但是其受体尚未确定,故论文就其受体研究的相关进展进行综述,为研究产气荚膜梭菌ε毒素诱导疾病的防治提供重要靶标。     

猪霉菌毒素中毒的防治措施

霉菌毒素中毒症是指与污染了霉菌毒素的食物或饲料接触而引发的疾病。产毒霉菌有数百种,主要的霉菌毒素有黄曲霉毒素、玉米赤霉烯酮、单端孢霉烯族毒素、烟曲霉毒素、赫曲毒素和麦角生物碱六大类。作物上的霉菌可在田间及在加工和贮存期间均能产生霉菌毒素。通常情况下,人或动物是通过食用受霉菌毒素污染的食品或饲料而发生中毒的。霉菌毒素在动物体内可产生多种生理作用：肝毒、肾毒、对中枢神经系统的作用以及类似雌激素效应等。     

无机盐和水吸收的生理机制

1钠离子的吸收 钠占体液阳离子总量的90%以上，肠内容物中95%-99%的钠均可被吸收。小肠各段都能吸收钠，但空肠对钠离子的吸收最快，回肠较慢，结肠更慢。钠协同转运系统，即与葡萄糖、氨基酸等相协同的主动转运系统。钠、氯同时吸收，此机制可能是由于在肠黏膜上皮细胞存在着与钠、氯转运有关的两个独立的离子转运系统。为发动此过程，肠上皮细胞内的水和二氧化碳在碳酸酐酶的作用下生成碳酸，后者很快分解成氢离子和碳酸氢根离子，细胞膜上的一个离子通道进行氢离子和钠离子交换，同时，另一个通道进行碳酸氢极离子和氯离子的交换。因为氢离子和碳酸氢根离子以相同的速度透出细胞，所以肠上皮细胞内的pH值保持不变，进入肠腔中氢离子和碳酸氢根离子又重新合成碳酸。进入细胞内的钠离子被钠泵酶主动转运至细胞间隙，氯离子则在细胞内蓄积并通过上皮细胞基底膜上的特殊通道排入细胞间隙。钠和氯的吸收速度取决于氯通道的通透性，通透性大，氯能很快离开上皮细胞，允许氯的继续吸收。此机制在回肠和结肠较为活跃。钠离子的单纯扩散，正常情况下肠腔内和血液内钠离子的浓度都是150毫摩尔/升，而肠上皮细胞内钠离子的浓度是15毫摩尔/升，钠离子可以顺电化学梯度通过扩散作用进入细胞内。而细胞内的钠离子通过基底膜进入血液则是逆电化学梯度进行的主动转运过程，此过程由钠泵钠泵协助进行，并由三磷酸腺苷分解供能。     

黄曲霉毒素的危害及检测方法的研究进展

黄曲霉毒素（AF）是由某些真菌产毒菌株产生的次生代谢产物,具有极强的毒性、致癌性,在自然界中普遍存在。AF不仅直接危害动物机体的健康,还可以通过食物链对人类健康造成极大的危害。随着技术的发展和各国的重视,其检测方法也不断发展。目前已有HPLC法、TLC法、ELISA法、SFB法等检测方法。本文主要就AF的危害及其检测方法作一综述。     

黄曲霉毒素的危害及检测方法的研究进展

黄曲霉毒素(AF)是由某些真茵产毒菌株产生的次生代谢产物,具有极强的毒性、致癌性,在自然界中普遍存在,AF不仅直接危害动物机体的健康,还可以通过食物链对人类健康造成极大的危害.随着技术的发展和各国的重视,其检测方法也不断发展.目前已有HPLC法、TLC法、ELISA法、SFB等检测方法.本文主要就AF的危害及其检测方法作一综述.     

大田软海绵酸致病性及检测方法研究进展

大田软海绵酸（okadaic acid,OA）属于海洋腹泻性贝毒,是一类常见的赤潮藻毒素,富集于多种海洋软体动物的消化腺内,食用被污染的海产品后会发生腹泻性中毒,中毒症状极易与细菌性胃肠炎混淆,且OA具有长期的致癌效应。作者就大田软海绵酸的结构性质、致病性及检测方法进行综述,以使公众进一步了解OA检测的公共卫生意义。     

电化学生物传感器在真菌毒素检测中的研究进展

真菌毒素是真菌在食品或饲料中生长所产生的代谢产物,这些低分子质量化合物既是天然存在的,同时也是无法避免的。真菌通过两种途径进入食物链,一方面可以直接从受真菌毒素污染的植物性食品成分进入食物链;另一方面也可以通过食物中产毒真菌生长的间接污染进入食物链。真菌毒素广泛存在于成熟的玉米、谷物、大豆、高粱、花生和饲料作物中。食用受真菌毒素污染的食物或饲料会对人和动物造成急性或慢性毒性。真菌毒素除了有直接食用受霉菌毒素污染的食物和饲料造成的不良影响外,还有因为摄入动物源性食品,如肉类、牛奶或鸡蛋,含有真菌毒素的残留物或代谢物而引起的公众健康问题。目前虽然已经鉴定出超过400种真菌毒素,但食物中广泛存在的6种毒素：黄曲霉毒素、赭曲霉毒素、玉米赤霉烯酮、伏马菌素、呕吐毒素及T-2毒素,已在世界范围内引发了持续的食品安全问题。该论文总结了6种真菌毒素的毒性,重点分析了近年来电化学生物传感器在这几种真菌毒素检测中的研究进展,旨在通过一系列的总结分析去展望其在真菌毒素检测方面的发展前景。     

霉菌毒素与微量元素代谢及肝脏氧化损伤的关系

<正>霉菌毒素是霉菌在以饲料为营养源的生长过程中产生的有毒化学物质。霉菌毒素在动物体内可产生多种生理作用——肝毒、肾毒、对中枢神经系统的作用以及类似雌激素效应等。有时,霉菌毒素在饲料中的浓度很高,危及动物的健康和生产     

Evaluation of serologic and viral detection methods for diagnosing feline herpesvirus-1 infection in cats with acute respiratory tract or chronic ocular disease

OBJECTIVE: To determine the value of virus isolation (VI), immunofluorescent antibody (IFA) assay, serum neutralization (SN), and ELISA for the diagnosis of clinical feline herpesvirus-1 (FHV-1) infection in cats. ANIMALS: 46 clinically normal cats, 17 cats with signs of acute respiratory tract disease, and 38 cats with signs of chronic ocular disease. PROCEDURE: Conjunctival swabs for VI, conjunctival scrapings for IFA testing, and venous blood samples for SN or ELISA testing were obtained from all cats. RESULTS: FHV-1 was detected in 10.9 and 28.3% of clinically normal cats and in 18.2 and 33.3% of cats with FHV-1-associated disease by VI and the IFA assay, respectively. There were no significant differences in the viral detection rate between cats with acute respiratory tract disease and cats with chronic ocular disease or between diseased cats and clinically normal cats; however, FHV-1 was never detected by both methods in clinically normal cats. Overall FHV-1 seroprevalence was 97% when tested by ELISA and 66% when tested by SN. Seroprevalence did not vary significantly among the 3 groups for either serologic test. Magnitude of SN and ELISA titers varied greatly but independently of presence or absence of clinical signs of FHV-1-associated disease. Sensitivity, specificity, and positive and negative predictive values were assessed for VI and the IFA assay--jointly and individually--and for each SN and ELISA titer magnitude. Values never all exceeded 50%. CLINICAL IMPLICATIONS: Because FHV-1 can be detected commonly in clinically normal cats by the IFA assay or VI, neither test appears to aid in the clinical diagnosis of FHV-1 infection. Seroprevalence does not appear to vary between affected and clinically normal cats. SN, ELISA, VI, and the IFA assay appear to be of limited value in the diagnosis of FHV-1-associated disease in cats. Concurrent assessment of the IFA assay and VI results may permit exclusion of FHV-1 as an etiologic agent if results of both tests are negative.     

常山酮残留检测方法的研究进展

常山酮是使用很广泛的一种抗球虫药,本文介绍了国内外对常山酮残留检测的气相色谱法、毛细管电泳法、高效液相色谱法（HPLC）、液质联用法和酶联免疫吸附法（ELISA）,并对ELISA和HPLC两种方法进行了比较.     

Comparison of a commercial enzyme-linked immunosorbent assay with electron microscopy, fluorescent antibody, and virus isolation for the detection of bovine and porcine rotavirus

The purpose in this study was to compare the sensitivity of a commercial enzyme-linked immunosorbent assay (ELISA) with electron microscopy (EM), fluorescent antibody (FA), and virus isolation (VI) for the detection of bovine and porcine rotavirus (RV). Seventy-three bovine and 116 porcine accessions were evaluated by 1 or all 4 diagnostic tests, where suitable specimens were available. For the bovine samples, agreement was 33% between FA and EM, 33% between FA and ELISA, and 92% between EM and ELISA. For the porcine samples, agreement was 79% between EM and FA, 72% between EM and ELISA, and 82% between ELISA and FA. Virus was isolated from 68% and 41% of the bovine and porcine fecal samples, respectively. Commercial ELISA was as sensitive as EM, but was more sensitive than FA or VI for the detection of RV in bovine feces. Electron microscopy was more sensitive than FA, ELISA, or VI for detection of RV in porcine feces. The ELISA was an advantageous alternative to the conventional methods of EM, FA, and VI for the diagnosis of RV in calf feces, but not for porcine feces.     

牛乳中黄曲霉毒素B_1和M_1检测方法的比较

比较了免疫亲和柱-高效液相色谱法(HPLC)和酶联免疫吸附法(ELISA)测定牛乳中黄曲霉毒素B1(AFB1)和M1(AFM1)的回收率、方法检出限及精密度。结果表明,HPLC法测定AFB1、AFM1的检测限分别为0.02和0.01μg·L-1,ELISA法测定AFB1、AFM1的最低检出限分别为0.05和0.02μg·L-1;阴性牛乳试样AFB1(0.003、0.006、0.012、0.024μg·kg~(-1))和AFM1(0.005、0.01、0.025、0.05μg·kg~(-1))的回收率试验表明,HPLC法测定AFB1与AFM1的回收率分别为77.58%~82.81%和77.51%~82.23%,变异系数分别为1.93%和3.51%;ELISA法测定AFB1与AFM1回收率分别为77.28%~79.11%和75.40%~76.34%,变异系数分别为2.20%和3.80%,两种方法测定AFB1的回收率差异不显著(P0.05),当AFM1添加浓度大于0.025μg·kg~(-1)时,HPLC法回收率显著高于ELISA法(P0.05);综上,两种方法灵敏度高、重复性好,HPLC法测定高浓度AFM1时准确性优于ELISA法。     

黄曲霉毒素危害、检测方法及生物降解研究进展

黄曲霉毒素(AF)是由某些真菌产毒菌株产生的次生代谢产物,具有极强的毒性.论文介绍了黄曲霉毒素对畜禽的危害以及薄层色谱(TLC)检测法、高效液相色谱(HPLC)检测法、酶联免疫(ELISA)检测法和放射免疫(RIA)检测法等检测方法,并对黄曲霉毒素生物降解的研究概况做一综述.     

Detection of aflatoxin B1 in imported food products into Japan by enzyme-linked immunosorbent assay and high performance liquid chromatography.

In order to detect the presence of aflatoxin B1 (AFB1), the use of the enzyme-linked immunosorbent assay (ELISA) and recovery test was evaluated. The detection limit of ELISA for AFB1 was 1 pg/assay and the recovery from maize spiked with AFB1 exceeded 80%. AFB1 was detected by ELISA in seven out of twelve samples of imported food products including peanut, almond, red pepper, cocoa bean, black pepper, buckwheat, walnut, adlay, soybean, popcorn, and pistachio nut, and by high performance liquid chromatography (HPLC) in four of the samples. However, the content of AFB1 in these samples was less than 10 ng/g of the minimum value authorized by the Japanese sanitation law. These results demonstrate that ELISA is more sensitive than HPLC and imported food products are broadly contaminated with AFB1.     

Beak trimming in turkeys

In Germany, Bio-beaker and infra-red irradiation (PSP) are used for beak trimming in turkey chicks as routine methods to prevent feather pecking and cannibalism. By both procedures the animals suffer from extensive damage and considerable continuous pain. Beak trimming is allowed by animal welfare legislation, but the operation requires an official permission and must be carried out under anesthesia. The official intention, due to animal welfare reasons, to decrease this operation and to question it permanently fails because beak trimming without anesthesia is tolerated. Elaboration of alternative programs has been demanded for a long time. Therefore selection of stocks tending less to cause feather pecking and cannibalism as well as adequate keeping and housing conditions during hatching and rearing are proposed.     

抗A型产气荚膜梭菌单克隆抗体的研制和鉴定

本试验用NSo细胞和产气荚膜梭菌肠毒素免疫的BALB／C小鼠脾细胞融合，获得了2株能分泌抗A型产气荚膜梭菌肠毒索单克隆抗体的杂交瘤细胞。经鉴定．这2株杂交瘤细胞的平均染色体数目为96．8条，单抗亚类为IgG1，杂交瘤细胞培养上清及腹水单克隆抗体的效价均较高，而且与其他几种常见的毒素SE、LT、S—LT、产气荚膜梭菌α毒素等不存在交叉反应。1D5能完全中和NCTC8239、S020718所产生的CPE的生物学活性，而284的中和活性则较差。     

Measurement of carbonic anhydrase isozyme VI (CA‐VI) in swine sera,colostrums, saliva,bile, seminal plasma and tissues

Swine secretory carbonic anhydrase VI (CA‐VI) was purified from swine saliva and an antibody to CA‐VI was generated. A specific and sensitive enzyme‐linked immunosorbent assay (ELISA) has been developed for the measurement of swine CA‐VI. The assay can detect as little as 5 ng/mL of swine CA‐VI. Typical standard curves were determined for a range of CA‐VI solutions (7.8 to 500 ng/mL). The coefficients of variation for these solutions were less than 5%. When 500, 250 or 100 ng/mL of swine CA‐VI was added to swine sera, the recoveries were 102.0%, 109.7% and 100.2%, respectively. The concentrations of CA‐VI in the saliva (26.2 ± 30.4 µg/mL), sera (3.3 ± 4.9 ng/mL), bile (153.0 ± 114.0 ng/mL), seminal plasma (124.0 ± 39.0 ng/mL) and parotid gland (441.3 ± 90.0 µg/g wet tissue), submaxillary gland (88.1 ± 124.4 µg/g wet tissue), sublingual gland (58.6 ± 24.6 µg/g wet tissue) and gallbladder (2.4 ± 1.3 µg/1g wet tissue) were determined by ELISA. The concentration of CA‐VI in colostrum was 163.3 ± 101.4 ng/mL and did not decrease within 10 days following parturition. An immunohistochemical reaction to anti‐CA‐VI antiserum was observed in the columnar epithelial cells lining the gallbladder. These data suggest that secretory CA‐VI plays various roles in pH regulation and the maintenance of ion and fluid balance.     

Comparison of the exotoxins of four strains of Corynebacterium pseudotuberculosis

The activity of exotoxins produced by four strains of Corynebacterium pseudotuberculosis were compared by their ability to kill white mice, their haemolytic activity, staphylococcal haemolysin-inhibiting effect and activity in an enzyme-linked immunosorbent assay (ELISA). Exotoxins with a haemolytic titre of 1 in 256 or more killed all mice and had the most inhibitory effect (1 in 64 or more) on staphylococcal haemolysin. The haemolytic test and staphylococcal haemolysin inhibitory test of exotoxin activities were highly correlated (P less than 0.001) with the mouse toxicity of the four exotoxins examined. No significant correlation was evident between the ELISA and relative toxicity of the exotoxins.