猪圆环病毒2型CAP蛋白B细胞表位预测与分析

基于PCV2 CAP蛋白的氨基酸序列,采用Kyte-Doolittle的亲水性方案、Emini方案、Karplus方案Jameson-wolf抗原指数方案,辅以对PCV2 CAP蛋白的二级结构柔性区域分析,并结合吴玉章氨基酸抗原指数计算方法预测CAP蛋白的B细胞表位。结果表明,最有可能的B细胞优势表位位于CAP蛋白N端第4~18,23~28,32~41,57~64,96~103,175~182区段和第224~233区段。本研究用多参数预测PCV2 CAP蛋白的B细胞表位,为多肽疫苗的设计提供理论依据。     

猪源戊型肝炎病毒ORF2蛋白生物信息学分析及真核表达研究

【目的】分析猪源戊型肝炎病毒(Swine hepatitis E virus, sHEV)4型ORF2蛋白的结构和功能,筛选具有保护性抗原的基因片段并表达蛋白,为研究其作为潜在保护性抗原提供候选蛋白。【方法】对sHEV 4型ORF2蛋白进行生物信息学分析,选取具有潜在保护性抗原蛋白的基因片段ORF2(128/140),通过PCR扩增、酶切后克隆至昆虫细胞表达载体,转染sf9细胞,通过Western blotting鉴定分析表达蛋白p128/p140。【结果】生物信息学分析显示,sHEV 4型ORF2蛋白存在2个稳定蛋白：p128和p140,分别含有496和476个氨基酸,二者皆为稳定蛋白,无跨膜区,蛋白二级结构主要以无规则卷曲为主。p128蛋白有11个T细胞表位、21个B细胞表位;p140蛋白有14个T细胞表位、18个B细胞表位。成功构建ORF2(128)、ORF2(140)2个基因的昆虫细胞表达载体,转染sf9细胞后经Western blotting检测发现,表达蛋白可被His标签单抗、sHEV抗体阳性血清识别。【结论】试验发现2个sHEV具有潜在保护性抗原的p128和p140蛋白,...     

PEDV M蛋白N端的1～20aa的序列结构与功能分析

为了分析猪流行性腹泻病毒(PEDV)M蛋白N端1～20 aa内的有效抗原表位核心序列,试验利用在线BcePred Prediction Server和TMHMM Server v2.0等软件对PEDV M蛋白进行B细胞抗原结合位点及二级结构分析预测,并结合Western-blot进行分析鉴定。结果表明:M蛋白N端S5IPVDEVI12为抗原位点核心序列。     

禽呼肠孤病毒σB和σC蛋白二级结构及其细胞抗原表位预测

研究旨在运用DNAStar生物软件及Garnier-Robson、Chou-Fasman等方法分析禽呼肠孤病毒(avian reovirus,ARV)标准毒株S1133重要结构蛋白σB和σC的二级结构及其T细胞和B细胞抗原表位。通过分析其亲水性、柔韧性、表面可及性和抗原指数等特性,对σB和σC蛋白的B细胞抗原表位进行预测;以Rothbard-Taylor和AMPHI方法预测σB和σC蛋白的T细胞抗原表位。结果显示,σB和σC蛋白形成α-螺旋结构的能力较差,但与σB蛋白相比,σC蛋白含有较多的β-折叠结构、转角及无规则卷曲等二级结构,因而σC蛋白二级结构较复杂。分析结果还表明σB和σC蛋白均含有潜在B细胞和T细胞抗原表位,尤其是σC蛋白具有较多的B细胞和T细胞抗原表位。本试验为深入研究σB和σC蛋白的免疫学特性及研发ARV新型疫苗和药物靶标奠定基础。     

禽呼肠孤病毒σB和σC蛋白二级结构及其细胞抗原表位预测

研究旨在运用DNAStar生物软件及Garnier-Robson、Chou-Fasman等方法分析禽呼肠孤病毒（avian reovirus,ARV）标准毒株S1133重要结构蛋白σB和σC的二级结构及其T细胞和B细胞抗原表位。通过分析其亲水性、柔韧性、表面可及性和抗原指数等特性,对σB和σC蛋白的B细胞抗原表位进行预测;以Rothbard-Taylor和AMPHI方法预测σB和σC蛋白的T细胞抗原表位。结果显示,σB和σC蛋白形成α-螺旋结构的能力较差,但与σB蛋白相比,σC蛋白含有较多的β-折叠结构、转角及无规则卷曲等二级结构,因而σC蛋白二级结构较复杂。分析结果还表明σB和σC蛋白均含有潜在B细胞和T细胞抗原表位,尤其是σC蛋白具有较多的B细胞和T细胞抗原表位。本试验为深入研究σB和σC蛋白的免疫学特性及研发ARV新型疫苗和药物靶标奠定基础。     

口蹄疫病毒O型泛亚株VP1蛋白的二级结构及抗原表位预测

为获得口蹄疫病毒（FMDV）O/PanAsia毒株VPl蛋白的抗原信息,从而为制备多肽疫苗提供理论依据,运用生物信息学软件,对O/PanAsia毒株的结构蛋白VP1理化性质、结构功能以及细胞表位进行分析,预测抗原表位以选择合适肽段。应用ProParam、TMHMM Server、ProScale和SignaIP 等在线工具,分析VP1蛋白氨基酸序列,运用计算机技术和分子生物学软件,分析预测VP1蛋白的基本理化性质、结构功能以及可能的B细胞和T细胞抗原表位,筛选B细胞表位肽段并对VP1的两个主要T细胞表位CTL和Th细胞表位进行预测。结果显示：O/PanAsia毒株VP1 蛋白的等电点为9.49,相对分子质量为23 520.83;VP1蛋白的B细胞表位为8~23、135~149和193~205位氨基酸。预测该VP1有10个CTL和10个Th细胞抗原表位,表明其具有较好的免疫原性;最终筛选出VP1蛋白的5个CTL和5个Th优势表位。用生物信息学方法预测O/PanAsia毒株VPl蛋白为稳定性蛋白,含有T、B淋巴细胞抗原表位。本研究为FMDV的进一步研究和疫苗制备奠定了基础。     

狐貉源犬瘟热病毒F蛋白基因的二级结构及其B细胞抗原表位预测

以犬瘟热病毒基因组序列为材料,采用Garnier-Robson、Chou-Farsman和Karplus-Schultz方法预测了其结构蛋白的二级结构,用Kyte-Doolittle方法对结构蛋白的亲水性进行了分析,用Emini方法预测了结构蛋白的表面可及性,以Jameson-Wolf方法预测了蛋白的抗原指数,综合评价了犬瘟热病毒F蛋白的B细胞抗原表位。结果表明:F蛋白N端含有抗原指数较高的区域,提示可能含有潜在的B细胞优势抗原表位。     

貉源阿留申病毒VP2和NS1蛋白的抗原性预测

旨在预测和分析貉源阿留申病毒（RFAV） VP2和NS1蛋白的抗原表位特征，筛选阿留申病毒属较保守的B、T细胞抗原表位。本研究对RFAV的近全长基因组进行克隆及测序，对其VP2和NS1基因编码蛋白的理化性质、二级结构、翻译后修饰位点和抗原表位进行预测，并将预测的修饰位点、抗原表位与其他阿留申病毒种的序列进行比较分析，筛选相对保守的修饰位点和抗原表位。结果显示，获得的RFAV基因组长4 327 bp，编码VP2蛋白的636个氨基酸，编码NS1蛋白的641个氨基酸。VP2和NS1蛋白均为亲水性蛋白，二级结构以无规则卷曲为主。在阿留申病毒属内，VP2蛋白有3个保守的B细胞抗原表位，3个保守的T细胞表位，8个保守的翻译后修饰位点；NS1蛋白有1个保守的B细胞抗原表位，2个保守的T细胞抗原表位和7个保守的翻译后修饰位点。本研究成功克隆了RFAV近全长基因组序列，全面对RFAV的VP2、NS1蛋白抗原表位、翻译后修饰位点进行预测，并分析其在阿留申病毒属内的保守和变异特征，为阿留申病毒免疫研究提供参考。     

血清4型Ⅰ群禽腺病毒四个主要结构蛋白的生物信息学分析

为了了解血清4型Ⅰ群禽腺病毒(serotype 4 of groupⅠFowl adenovirus)分离株RZ140718(RZ株)的hexon、penton、fiber-1和fiber-2四个主要结构蛋白的遗传进化、二级结构及抗原表位等生物学信息,试验在对四个蛋白基因扩增测序基础上,应用Megalign、MEGA 5.1软件进行氨基酸序列分析并构建系统发育进化树,应用ProtParam、SignalP和SOPMA软件分析理化性质和二级结构,应用BepiPred、ABCpred、IEDB和DNAStar软件综合预测B细胞抗原表位,应用NetMHCpan4.0和NetMHCⅡpan3.2软件预测T细胞抗原表位。结果表明:从RZ株中PCR扩增出hexon、penton、fiber-1和fiber-2这四个蛋白的基因;RZ株的hexon和penton蛋白与GenBank中12个血清型参考株的同源性较高,fiber-1和fiber-2蛋白与4型和10型参考株的同源性较高;RZ株的四个蛋白与GenBank中其他4型中国分离株均位于同一分支上;四个蛋白均为酸性亲水蛋白,无信号肽,均以无规卷曲为主;从四个蛋白中分别得到22,11,11,10个潜在的线性B细胞抗原表位,4,2,4,2个潜在的CTL细胞抗原表位,2,1,1,0个潜在的Th细胞抗原表位。说明hexon蛋白具有较多的潜在优势抗原表位,可用于后续表位疫苗的开发研究。     

犬瘟热病毒N蛋白的B细胞抗原表位预测

将1段犬瘟热病毒N蛋白氨基酸序列(GenBank编号为:AEV77096.1)与Gen Bank登录的其他氨基酸序列进行比对,分析其同源性;通过DNAStar生物信息学分析软件中的Protean模块及The PredictProtein server在线蛋白分析工具预测犬瘟热病毒N蛋白的理化性质、二级结构、亲水性、表面可及性、柔韧性、抗原指数、跨膜螺旋、蛋白相互作用位点、蛋白功能位点等特性,并预测其B细胞优势抗原表位。结果显示,犬瘟热病毒N蛋白具有规则的二级结构、亲水性、柔韧性片段多,多处于表面可及性大,抗原指数高,蛋白质相互作用位点区域。潜在的B细胞优势抗原表位为12¹8、6118、61⁶6、24366、243²46、410246、410⁴15、421415、421⁴29、434429、434⁴47、452447、452⁴56、480456、480⁴87氨基酸序列。结果表明,本试验预测了犬瘟热病毒N蛋白的B细胞优势抗原表位,为进一步设计犬瘟热病毒的诊断抗原多肽、免疫用抗原多肽和研发血清学检测试剂盒奠定了理论基础。     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.     

Mechanism of Action of Probiotic Function of Lactobacilli

乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制.     

Evaluation of serum concentrations of biomarkers of skeletal metabolism and results of radiography as indicators of severity of osteochondrosis in foals

OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis.