部分地区猪细环病毒1型感染的流行情况调查

猪细环病毒1型是近年来发现的又一种环状DNA病毒,可能存在潜在致病作用.为了初步了解其流行情况,用PCR技术和ELISA技术对来自京津冀、华东与华南地区578头保育猪血清样品进行了检测.结果显示,猪细环病毒1型的核酸与抗体的猪场阳性率均为100％;核酸阳性率为73.88％,抗体阳性率为78.72％,二者之间无显著差异(...     

PCR结合分子杂交法检测鸡传染性支气管炎病毒

利用逆转录－ＰＣＲ（ＲＴ－ＰＣＲ）特异性扩增鸡传染性支气管炎病毒（ＩＢＶ）基因组中Ｍ基因和Ｎ基因之间一段核酸片段。以ｐＵＣ１９质粒载体将此片段克隆，用ＥｃｏＲＩ和ＨｉｎｄⅢ酶切此重组质粒，回收克隆片段后，制成生物素标记的核酸探针。用ＲＴ－ＰＣＲ及生物素核酸探针法分别对ＩＢＶ，ＩＢＤＶ，ＩＬＴＶ，ＭＤＶ及ＮＤＶ进行检测，结果证明该方法为ＩＢＶ特异性检测方法。对人工感染ＩＢＶ的ＳＰＦ鸡口腔棉拭样品进行跟踪检测，证明本方法能在ＳＰＦ鸡接毒后１～１０ｄ内检出ＩＢＶ。     

免疫抑制对苏拉灭和贝尼尔治疗小鼠伊氏锥虫病疗效的影响

用从自然感染宿主分离的伊氏锥虫原种ＪＧ的克隆ＪＧｍｃ１和ＪＧｍｃ５感染免疫活性正常小鼠和免疫抑制小鼠，２４ｈ后，以苏拉灭或贝尼尔治疗，两种药物对免疫抑制小鼠的ＣＤ１００均明显高于免疫活性正常小鼠，由经受一次苏拉灭或贝尼尔治疗未愈的免疫抑制小鼠分离的锥虫，感染免疫活性正常小鼠，再用原来对该克隆感染的免疫活性正常小鼠ＣＤ１００的苏拉灭或贝尼尔治疗即无效。用免疫溶解试验分别测定一组免疫抑制和免疫活性正确     

A cluster of two psittacosis cases among women farmers exposed to Chlamydia psittaci-infected domestic poultry in Zhejiang Province,China

A cluster of Chlamydia psittaci (C. psittaci) cases was reported in Zhejiang Province, China, 2019. This study evaluates the extent of the outbreak and determines the source of infection. Real-time PCR and sequencing of the ompA gene of C. psittaci were performed to identify the cases, the domesticated poultry and close contacts. The index patient was a 76-year-old woman with chronic vertigo, and Case 2 was a 64-year-old female farmer with herpes zoster. Both women bought psittaci-infected chickens or ducks from the same mobile street vendor and raised them for 10 days and 23 days before fever onset. There were no direct contact between the two women. C. psittaci test was positive for the two patients, one sick chicken, three healthy ducks and the vendor's chicken cage. Phylogenetic analysis showed that all seven C. psittaci positive samples carried identical ompA genotype A of C. psittaci. Of all of the patients' 148 close contacts, none tested positive for C. psittaci, or developed acute respiratory symptoms. Both patients were discharged after a 4-week hospital stay. In conclusion, the source of this cluster was the poultry infected with C. psittaci, which occasionally cause infections in farmers, but inter-human transmission seems unlikely.     

Spatiotemporal heterogeneity of PPARγ expression in porcine uteroplacenta for regulating of placental angiogenesis through VEGF-mediated signalling

Non-infectious prenatal mortality severely affects the porcine industry, with pathological placentation as a likely key reason. Previous studies have demonstrated that peroxisome proliferator-activated receptor gamma (PPARγ) deficiency causes defects in the uteroplacental vasculature and induces embryonic losses in mice. However, its role in porcine placental angiogenesis remains unclear. In the present study, PPARγ expression was investigated in porcine uteroplacental tissues at gestational day (GD) 25, GD40 and GD70 via quantitative polymerase chain reaction (qPCR), Western blot and immunohistochemistry (IHC). Moreover, the roles of PPARγ in porcine placental angiogenesis were investigated using a cell model of porcine umbilical vein endothelial cells (PUVECs) to conduct proliferation, migration and tube formation assays in vitro and a mouse xenograft model to assess capillary formation in vivo. The results showed that PPARγ was mainly located in the glandular epithelium, trophoblast, amniotic chorion epithelium and vascular endothelium, as indicated by the higher expression levels at GD25 and GD40 than at GD70 in endometrium and by higher expression levels at GD40 and GD70 than at GD25 in placenta. Moreover, PPARγ expression was significantly downregulated in placenta with dead foetus. In PUVECs, knocking out PPARγ significantly inhibited proliferation, migration and tube formation in vitro and inhibited capillary formation in mouse xenografts in vivo by blocking S-phase, promoting apoptosis and downregulating the angiogenic factors of VEGF and its receptors. Overall, the spatiotemporal heterogeneity of PPARγ expression in porcine uteroplacental tissue suggests its vital role in endometrial remodelling and placental angiogenesis, and PPARγ regulates placental angiogenesis through VEGF-mediated signalling.     

Pharmacokinetics and bioavailability of valnemulin in broiler chickens

Wang, R., Yuan, L.G., He, L.M., Zhu, L.X., Luo, X.Y., Zhang, C.Y., Yu, J.J., Fang, B.H., Liu, Y.H. Pharmacokinetics and bioavailability of valnemulin in broiler chickens. J. vet. Pharmacol. Therap. 34 , 247–251. The objective of this study was to investigate the pharmacokinetics and bioavailability of valnemulin in broiler chickens after intravenous (i.v.), intramuscular (i.m.) and oral administrations of 10 mg/kg body weight (bw). Plasma samples were analyzed by high‐performance liquid chromatography–tandem mass spectrometry (HPLC‐MS/MS). Pharmacokinetic characterization was performed by non‐compartmental analysis using WinNonlin program. After intravenous administration, distribution was wide with the volume of distribution based on terminal phase(V_z) of 4.27 ± 0.99 L /kg. Mean valnemulin t_1/2β(h), Cl_β(L /h /kg), V_ss (L /kg) and AUC_(0–∞)(μg·h /mL) values were 2.85, 0.99, 2.72 and 10.34, respectively. After intramuscular administration, valnemulin was rapidly absorbed with a C_max of 2.2 μg/mL achieved at 0.43 h (t_max), and the absolute bioavailability (F) was 88.81%; and for the oral route the same parameters were 0.66 ± 0.15 μg/mL, 1.54 ± 0.27 h and 74.42%. A multiple‐peak phenomenon was present after oral administration. The plasma profile of valnemulin exhibited a secondary peak during 2–6 h and a tertiary peak at 32 h. The favorable PK behavior, such as the wide distribution, slow elimination and acceptable bioavailability indicated that it is likely to be effective in chickens.     

DNA Methylation Pattern in Pronuclear-Stage Mouse Embryos: Effect of Oocyte Vitrification

This study was conducted to investigate the pattern of DNA methylation in pronuclearstage mouse embryos derived from vitrified-warmed oocytes.Mouse oocytes at metaphase Ⅱ (MⅡ) stage of meiosis were all...     

中国荷斯坦牛乳蛋白分子遗传多态性和产奶性状相关性的研究

从北京两个主要牛场共采得１８７头中国荷斯坦奶牛的血样,提取基因组ＤＮＡ,通过ＰＣＲ－ＲＦＬＰ方法对Ｋａｐｐａ酪蛋白、Ｂｅｔａ乳球蛋白（βｌｇ）和Ａｌｐｈａ乳白蛋白（α－ｌａ）进行了基因型的鉴定,并结合产奶性状进行统计分析,结果表明,牛群中上述３种乳蛋白基因的基因频率分别为Ｋ－ｃｎＡ７９％,Ｋ－ｃａＢ２１％,β－ｌｇＡ４３％,β－ｌｇＢ５７％,α－ｌｇＢ１００％,Ｋ－ＣＮ和β－ｌｇ基因位眯对产奶量没     

牛支原体和牛病毒性腹泻病毒二重二温式PCR检测方法的建立

为建立一种牛支原体(Mycoplasma bovis,MB)和牛病毒性腹泻病毒(Bovine viral diarrhea virus,BVDV)的快速鉴别诊断方法,针对MB的uvr C基因和BVDV的5'端非编码区(5'-UTR)保守基因序列,分别设计两对特异引物,并将三温式PCR扩增程序简化为二个温度梯度,建立了鉴别MB和BVDV的二重二温式PCR方法。该方法能同时扩增MB和BVDV,扩增产物大小分别为412和170 bp。特异性试验结果显示,该方法对参试的所有毒株只扩增MB和BVDV基因组,对其它牛病原体无扩增;敏感性试验结果显示,该方法最低能同时检测到104拷贝的两种目的核酸;干扰性试验结果显示,该方法能同时检测两个模板不同浓度的组合,试验结果不受模板影响。综上,本研究所建立的二重二温式PCR方法特异、敏感、快速、简便,可应用于MB和BVDV临床鉴别诊断和流行病学调查。