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1.
为了提高猪传染性胸膜肺炎灭活苗的保护力,本研究利用基因重组技术表达了猪传染性胸膜肺炎放线杆菌6种主要致病因子蛋白:rApxⅠ、rApxⅡ、rApxⅢ、rApxⅣ、rApfa和rOMP。设立试验Ⅰ组(灭活苗),试验Ⅱ组(灭活苗、rApxⅠ、rApxⅡ、rApxⅢ和rOMP),试验Ⅲ组(灭活苗、rApxⅠ、rApxⅡ、rApxⅢ和rApxⅣ),试验Ⅳ组(灭活苗、rApxⅠ、rApxⅡ、rApxⅢ和rApfa)和空白对照组(PBS),每组26只BALB/c小鼠,分3次免疫,每次间隔2周,每周检测血清抗体水平,在免疫后第2周、第4周和第5周,MTT法检测脾脏T细胞增殖水平及ELISA法测定IFN-γ分泌水平。在第3次免疫后的第7 d,将每组剩余20只小鼠平均分成2组,分别以APP1型菌(5×10~9 CFU)和APP7型菌(1×10~(11) CFU)进行攻毒保护试验。结果表明,向灭活苗中添加重组亚单位成份可以提高机体的细胞免疫和体液免疫水平,并能提高灭活苗的交叉保护率;试验Ⅱ组的ApxⅠ和OMP抗体水平以及细胞免疫水平均显著高于其它各组(p<0.05),对于APP1和APP7型菌的攻毒也提供了明显优于其它各组的保护结果,试验Ⅲ、Ⅳ组的细胞、体液免疫水平及保护率较试验Ⅰ组也有所提高。结果显示出ApxⅠ、OMP抗体水平和细胞免疫水平与攻毒保护率之间存在着正相关性,向灭活苗中加入重组蛋白成份可以提高疫苗的交叉保护,试验Ⅱ组通过激活体液免疫和细胞免疫,对两个血清型APP的攻击提供了很好的保护作用,从而为猪传染性胸膜肺炎新型疫苗的研制提供参考。  相似文献   

2.
为研制以胸膜肺炎放线杆菌(APP) 4种外毒素蛋白(ApxⅠA、ApxⅡA、ApxⅢA、ApxⅣA)和外膜蛋白(OMP)为组分的亚单位疫苗,在本研究室已表达纯化的r ApxⅠA、r ApxⅡA、r OMP的基础上,本研究通过PCR扩增得到ApxⅢA、ApxⅣA基因,并分别将其克隆至表达载体p ET-32a中,测序验证后将重组质粒转化入宿主菌BL21 (DE3),经IPTG诱导表达后获得重组蛋白r ApxⅢA和r ApxⅣA。将获得的5种蛋白(rApxⅠA、r ApxⅡA、r ApxⅢA、r ApxⅣA和r OMP)按一定比例混合制备成亚单位疫苗免疫BALB/c雌鼠进行免疫效果测定,设灭活疫苗组(Ⅰ组)、弗氏佐剂乳化的亚单位疫苗组(Ⅱ组)、白油佐剂乳化的亚单位疫苗组(Ⅲ组)、灭活疫苗+白油佐剂乳化的亚单位疫苗组(Ⅳ组)和PBS组(Ⅴ组)。Western blot结果显示,表达了重组蛋白r ApxⅢA和r ApxⅣA且具有较好的反应原性;抗体检测结果显示,加强免疫后,Ⅱ组、Ⅲ组和Ⅳ组的r ApxⅠA、r ApxⅢA、r ApxⅣA和r OMP抗体水平基本一致(p0.05),均显著高于Ⅴ组和Ⅰ组(p0.05);攻毒保护试验结果显示,Ⅱ组与Ⅲ组保护率一致(p0.05),显著高于Ⅴ组(p0.05)。表明本研究中的亚单位疫苗具有一定的免疫保护效果,为猪传染性胸膜肺炎新型疫苗的研制提供参考。  相似文献   

3.
为评价金黄色葡萄球菌(S. aureus)Csa1A、Hlɑ和EsxA-B蛋白的免疫保护作用,本研究构建了重组质粒p GEX-4T-2-Csa1A、pET-22b-Hlα、pGEX-4T-2-EsxA-B并分别转化大肠杆菌BL21(DE3),经IPTG诱导并利用相应层析柱纯化后,采用SDS-PAGE检测重组蛋白的表达。结果显示,获得了纯度较高的重组蛋白Csa1A(rCsa1A)、Hlɑ(r Hlɑ)和EsxA-B(r EsxA-B),纯度分别为89%、95%、85%,大小分别为54 ku、33 ku和39 ku。以纯化的r Csa1A、rHlɑ和rEsxA-B 60μg/只分别免疫BALB/c小鼠,共免疫3次,每次间隔14 d,采用间接ELISA法检测各组小鼠免疫后14 d的抗体效价。结果显示,3种重组蛋白免疫后均能刺激小鼠产生较高效价的抗体,三免后抗体效价分别为1:14 700(rCsa1A)、1:16 890(rHlɑ)、1:15 760(rEsxA-B)。利用5型NM2株(2×107cfu/只)、8型LZ145株(2×10~7cfu/只)、336型XJ44株(2×10~7cfu/只)3种血清型S. aureus分别经尾静脉注射攻菌,观察并统计各组小鼠的发病和死亡率,评价各重组蛋白的免疫保护率。结果显示,分别经原核表达了rCsa1A、rHlɑ和rEsxAB。攻菌后对照组小鼠全部死亡;3组重组蛋白免疫组96 h内死亡的小鼠在攻菌48 h后出现精神沉郁,食欲不振等症状,而存活小鼠未出现临床症状。r Csa1A、rHlɑ和rEsxA-B免疫组小鼠提供的抵抗NM2、LZ145、XJ44菌株攻击的保护率分别为60%、60%、50%;80%、70%、70%;50%、60%、60%,其中rHlα的免疫保护效果最佳,其对3种攻毒菌株提供的平均保护率为73.3%,是较为理想的亚单位疫苗候选抗原。以上结果表明,S. aureus rHlα能够刺激免疫小鼠产生抗体,对小鼠提供不同程度的保护力。本研究为奶牛乳腺炎S. aureus亚单位疫苗的研制和应用提供参考依据。  相似文献   

4.
猪传染性胸膜肺炎新型亚单位菌苗对小鼠的效力研究   总被引：8，自引：2，他引：8  
利用大肠杆菌表达猪胸膜肺炎放线杆菌的分泌毒素ApxⅠ、ApxⅡ、ApxⅢ，提取表达产物包涵体，再加入我国流行的猪胸膜肺炎放线杆菌7型菌，和等量弗氏佐剂乳化后制成亚单位菌苗，免疫BALB／c小鼠，间隔2周加强免疫1次。每次免疫后采血检测毒素I、Ⅱ、Ⅲ的EuSA抗体和7型菌的血凝抗体，第2次免疫2周后用5LDso的猪胸膜肺炎放线杆菌1型、7型菌株进行攻毒。结果发现第2次免疫后抗体水平显著升高，用2种血清型进行攻毒后其保护力分别为83．3％和91．7％，从死亡小鼠的体内分离到了攻毒菌株，初步的动物试验表明此种新型亚单位菌苗对同型和异型的APP菌株具有较好的保护力，为进一步研制高效的亚单位菌苗打下基础。  相似文献   

5.
采用酚-水法制备血清3型、4型、5型、7型和8型猪胸膜肺炎放线杆菌（APP）脂多糖（LPS），以该多糖免疫小鼠，进行同源攻毒保护试验，结果LPS在20斗∥只的免疫剂量下可对小鼠产生较强的保护作用，用同血清型菌株对免疫后的小鼠攻毒，仅表现肺脏轻微出血，无死亡，而对照组未经免疫直接攻毒的小白鼠全部死亡，肺脏严重出血；小鼠免疫后第2d就可以检测到抗体，并且抗体水平上升较快，到第6d抗体达到最高水平，之后，抗体水平开始下降，但下降幅度不大，可持续2个月左右；交叉保护试验结果表明血清3型LPS对血清5型和7型APP，血清4型LPS对血清5型和7型APP没有保护作用，免疫后的小鼠攻毒仍表现多数死亡；血清3型LPS对血清4型和8型APP有交叉保护作用，血清4型LPS对血清3型和8型APP有交叉保护作用，血清5型、7型、8型LPS对5个血清型的APP都有交叉保护作用，免疫后的小鼠攻毒无死亡，仅表现肺脏有不同程度的出血。上述结果表明LPS是APP的主要免疫保护性抗原之一，该研究为APP亚单位疫苗的研制及应用提供了理论依据。  相似文献   

6.
将猪传染性胸膜肺炎放线杆菌ApxⅡ毒素的结构基因ApxⅡA克隆到原核表达载体pGEX-6P-1，并在大肠埃希氏菌中进行了表达，表达产物rApxⅡA以包涵体形式存在。为了检测rApxⅡA的免疫原性，分别用rApxⅡA、灭活疫苗以及灭活疫苗添加rApxⅡA对比利时白兔进行了免疫。免疫后进行攻毒，所用菌株分别为同型菌株（APP7型L25—4株）和异型菌株（APP1型4074株）。结果，免疫动物对相同血清型菌株的攻击获得完全保护，且对异型菌的攻击也获得一定保护作用。表明，rApxⅡA蛋白具有良好的免疫原性，作为抗原成分添加到灭活疫苗中后可提高灭活疫苗的免疫效果。  相似文献   

7.
为评价大肠杆菌(E.coli)外膜蛋白酶T(OmpT)的免疫原性及对小鼠的免疫效率,本研究将原核重组表达纯化的OmpT蛋白(rOmpT)免疫小鼠,并以灭活的E.coli 308-2全菌疫苗株作为对照组,通过检测其抗体效价、体外调理吞噬作用和细胞因子表达水平以及攻毒试验进行保护效率评价。结果表明rOmpT免疫组在二免后14 d其抗体水平可以达到峰值(1∶64 000),并且其抗血清具有显著促进巨噬细胞对E.coli的吞噬作用;同时,重组蛋白与全菌免疫组均能够显著提高小鼠体内IL-4和IFN-γ的表达。而且重组蛋白免疫组对4个进化种系(Phylogenetic group)的E.coli攻毒的免疫保护率均为60%左右,比全菌免疫组高约10%。研究结果显示rOmpT比全菌灭活E.coli能够诱导小鼠产生更有效免疫保护作用,表明rOmpT可以作为E.coli亚单位疫苗候选蛋白。  相似文献   

8.
研究猪肺炎支原体168(Mycoplasma hyopneumoniae 168,Mhp168)弱毒株重组蛋白p65的免疫原性。根据GenBank中Mhp168弱毒株P65基因的开放阅读框设计特异性引物,进行PCR扩增,构建原核表达载体pET-28a-P65,经原核表达并纯化获得的重组蛋白与佐剂以体积比1∶1乳化后免疫注射小鼠,通过酶联免疫吸附试验(ELISA)测定小鼠血清的抗体效价;选取抗体效价较高的小鼠进行攻毒试验。经间接ELISA证明,重组蛋白p65具有良好的免疫原性,血清效价为1∶12 800。攻毒试验证明,p65重组蛋白疫苗的保护率可达80%,证明重组蛋白p65具有良好的免疫原性。  相似文献   

9.
鸡新城疫病毒HN基因亚单位疫苗诱导免疫保护的实验研究   总被引：3，自引：0，他引：3  
实验分别将应用Bac to Bac系统表达的新城疫病毒四平株和长春株血凝素-神经氨酸酶基因（HN基因）蛋白的重组杆状病毒感染Sf-9昆虫细胞后28℃培养72h后，洗涤、收集昆虫细胞，离心浓缩，-20℃冻融3次，用HA-HI实验和HN单抗中和试验测定表达产物的活性，将表达的重组蛋白作为亚单位疫苗免疫鸡，用间接ELISA和HI试验测定鸡体内抗体效价，免疫后第15d用国家标准强毒NDVF48E8攻毒，统计免疫保护率，结果表明，表达的NDVHN重组蛋白能够诱导鸡体产生抗NDV特异性IgG抗体和HI抗体，实验Ⅰ组（四平株）雏鸡保护率为65%，实验Ⅱ组（长春株）雏鸡保护率为100%。  相似文献   

10.
为研究痤疮丙酸杆菌(PA)对小鼠抗胸膜肺炎放线杆菌感染的影响,从人的面部皮肤分离得到革兰氏阳性短杆菌,通过培养性状观察、生化试验、PCR鉴定,证实7株菌为PA.经ELISA检测发现PA与猪传染性胸膜肺炎放线杆菌(APP)存在免疫交叉反应.以PA免疫小鼠15 d后用10倍LD50的APP攻毒,观察1周,最高保护率为60%;将制备的抗PA高免血清注射小鼠,分别用10倍LD50的APP血清1型、APP血清5型感染小鼠,保护率均为100%.结果表明,PA对APP血清1型,APP血清5型感染具有良好的保护作用.  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
Tropical Animal Health and Production -  相似文献   

14.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

17.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

18.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

19.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

20.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

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