Adenosine A2A receptor agonists inhibit lipopolysaccharide-induced production of tumor necrosis factor-alpha by equine monocytes

Adenosine is an endogenous nucleoside that regulates many physiological processes by activating one or more adenosine receptor subtypes, namely A1, A2A, A2B and A3. The results of previous studies indicate that adenosine analogues inhibit lipopolysaccharide (LPS)-induced production of reactive oxygen species (ROS) by equine neutrophils primarily through activation of A2A receptors. Because peripheral blood monocytes produce cytokines that are responsible for many of the deleterious effects of LPS, the current study was performed to evaluate the effects of an array of novel adenosine receptor agonists on LPS-induced production of tumor necrosis factor-alpha (TNF-alpha), and to assess the selectively of these agonists for equine adenosine A2A over the A1 receptor. Radioligand binding studies performed with equine tissues expressing adenosine A1 and A2A receptor subtypes yielded a rank order of affinity for the equine A2A receptor of ATL307>ATL309 approximately ATL310 approximately ATL313>ATL202 approximately ATL361 approximately ATL376>ATL372>CGS21680>NECA. Co-incubation of equine peripheral blood monocytes with LPS and these agonists resulted in inhibition of TNF-alpha production with a rank order of potency that strongly correlated with their binding affinities for equine adenosine A2A receptors. Results of experiments performed with one of the adenosine receptor agonists (ATL313) and selective adenosine receptor antagonists confirmed that inhibition of LPS-induced production of TNF-alpha occurred via stimulation of A2A receptors. Although incubation of monocytes with IB-MECA, a compound purported to act as an adenosine A3 receptor agonist, reduced LPS-induced TNF-alpha production, this effect of IB-MECA was inhibited by the A2A selective antagonist ZM241385 but not by the A3 receptor antagonist MRS1220. These results indicate that the adenosine receptor subtype responsible for regulation of LPS-induced cytokine production by equine monocytes is the A2A receptor. To address the signal transduction mechanism responsible for the anti-inflammatory effects of ATL313 in equine monocytes, production of cAMP was compared in the presence and absence of either the adenosine A2A receptor antagonist ZM241385 or the adenosine A2B receptor antagonist MRS1706. In the absence of the antagonists, ATL313 increased production of cAMP; ZM241385 inhibited this effect of ATL313, whereas MRS1706 did not. Furthermore, incubation of monocytes with either the stable analogue of cAMP, dibutyryl cAMP, or forskolin, an activator of adenylyl cyclase, also inhibited LPS-induced production of TNF-alpha production by equine monocytes. Collectively, the results of the current study indicate that adenosine analogues inhibit LPS-induced production of TNF-alpha by equine monocytes primarily via activation of adenosine A2A receptors and do so in a cAMP-dependent manner. The results of this study indicate that stable adenosine analogues that are selective for adenosine A2A receptors may be suitable for development as anti-inflammatory drugs in horses.     

根据个体间蛋白质多位点基因型的比较分析中国黄牛的遗传关系

现行群体间遗传距离的度量方法都以等位基因频率的计算为依据，这些方法的缺点之一是在位点不多，多态笥不高时要求群体有较大的取样个体数目，另外，这些方法所建造的树素图不能反映群体是由混血引起还是由长期进化引起这一问题，针对这些问题，本文提出了以个体间蛋白质多位点基因型比较为基础的群体间遗传距离和群体内基因杂合度的度量方法，以十个主要中国黄牛群体的遗传关系分析为例，比较圆满的解决了上面几个问题。     

改性蒙脱石钙黏土(脱霉素)人体短期安全评估

脱霉素(NS)在多种动物身上均可对黄曲霉毒素引起的不良影响起到保护作用,因为其降低了黄曲霉毒素(AFs)在胃肠道中的生物利用。假定脱霉素可以安全地添加到人的日粮中,就可以减少人对黄曲霉毒素污染食物的接触及其健康风险。为了鉴定脱霉素对人的安全性及耐受性,建立长期功效研究的剂量确定方案,我们进行了随机双盲一期临床试验。临床审查志愿者(年龄在20～45岁),确认其健康状况。50个受试者(女性23人,男性27人)随机分成2组:低剂量组9个胶囊含1.5g/d,高剂量组9个胶囊含3.0g/d,试验周期为2周。脱霉素胶囊做的颜色和大小相同,每天分3次在指定地点分发给每个参与者,并跟踪记录每组的副反应和疾病情况。在实验室分析研究前后分别收集血液和尿样。所有参与者均完成了本试验,依从性99.1%。在一些参与者中出现了轻微的胃肠反应。症状包括腹痛(6%,3/50)、胃气胀(4%,2/50)、便秘(2%,1/50)、腹泻(2%,1/50)、胃肠气胀(8%,4/50)。两组之间的这些副作用没有统计学意义(p0.25)。每组中血液学、肝肾功能、电解质、VA和VE、矿物质等均无明显差别。这些结果表明脱霉素在人体应用是相对安全的,这可作为黄曲霉毒素中毒症高危人群长期人体试验的一个依据。     

High prevalence of bovine viral diarrhea virus 1 in Chinese swine herds

Nested RT-PCR was used to investigate bovine viral diarrhea virus in 511 specimens collected from Chinese pigs exhibiting clinical symptoms between 2007 and 2010. Of these, 137 samples were BVDV-positive and the BVDV prevalence rate was 23.1% (9/39) in 2007, 27.7% (44/159) in 2008, 33.6% (34/101) in 2009, and 23.6% (50/212) in 2010. Twenty of 137 BVDV-positive samples were used for further genetic analysis of the 5'-UTR. Phylogenetic analysis revealed that they were BVDV-1 and subtyped into BVDV-1a, BVDV-1b, BVDV-1m, BVDV-1o and an unknown subgenotype. This study showed that BVDVs were highly prevalent in Chinese pig herds and appropriate measures should be taken to control BVDV prevalence in pig herds.     

野马追克喘散治疗猪呼吸道疾病效果试验

目的：应用野马追克喘散新兽药对呼吸道综合征进行临床疗效试验,为推广野马追克喘散提供科学依据。方法：将自然感染、症状典型、猪呼吸道综合征的140头病猪（杜长大三元杂交）,平均体重20～25kg,随机分为7个组,每组20头,其中第Ⅰ、Ⅱ、Ⅲ组用野马追克喘散治疗,分别以高、中、低剂量给药;第Ⅳ、Ⅴ组分别用麻杏石甘散、金花平喘散以常规剂量给药;Ⅵ、Ⅶ组以硫酸卡那霉素注射液（0.2mL/kg体重）和泰乐菌素（0.4mL/kg体重）以常规剂量给药。结果：野马追克喘散的治疗效果较麻杏石甘散和金花平喘散治疗效果好,治愈率也达93.3%。结论：野马追克喘散治疗猪气喘咳嗽疗效较高,收效较快,维持时间较长,是较理想的药物。     

Inhibition of porcine circovirus type 1 and type 2 production in PK-15 cells by small interfering RNAs targeting the Rep gene

Porcine circovirus type 1 (PCV1) and type 2 (PCV2) are two genotypes of porcine circovirus. Both of them are presumed to be widespread in the swine population. Currently, there is no specific treatment for their infections. RNA interference (RNAi) is a sequence-specific RNA degradation mechanism mediated by small interfering RNA (siRNA), which represents a possible therapeutic application for the treatment of viral infections. In this study, three siRNA expression plasmids (pS-RepA, pS-RepB and pS-RepC) were generated to target three different coding regions of the Rep protein (Rep) of PCV. These siRNAs were used to inhibit PCV production in a porcine kidney cell line, PK-15 cells. Our results revealed that Rep gene expression was inhibited by pS-RepA, pS-RepB and pS-RepC to different degrees. Moreover, our study also showed that the production of PCV1 and PCV2 was reduced by these siRNAs. pS-RepC, which targets the middle region of Rep gene, proved to be the most efficient siRNA for inhibition of Rep expression and viral production. Taken together, our data suggest that RNAi could be investigated as a potential treatment for PCV infection.     

用波尔山羊改良贵州本地黑山羊的情况初报

贵州本地黑山羊在农村饲养条件下,由于诸多因素的影响,特别是农户养羊的传统意识与方法落后,加之品种的退化,造成了本地黑山羊生长发育慢,产肉率低,经济效益差的现状。为充分挖掘我县山羊的资源与生产潜力,不断提高养羊经济效益,我县于2001年开始引进世界著名的优良肉用山羊品种——波尔山羊,对本地黑山羊进行杂交改良。为了掌握波本F1代的生产性能和波尔山羊与本地黑山羊的杂交改良效果,     

新型装配式6列卧栏牛舍的研究与应用

我们对国内外牛的养殖模式进行研究后．为了更有效地提高土地利用率，减少奶牛疫病的发生，经过与有关专家以及有多年经验的养殖场的场长反复研究．最终推出了32m跨带卧栏的新型装配式牛舍．并且已经在张家口地区得以建设实施。这种牛舍具有便于清粪，便于料车开进牛舍进行饲喂，保护动物不受天气的影响，每个牛圈的成本降低等优点。具体研究过程介绍如下。     

天祝县牧区开发示范工程项目草地围栏建设及其综合效益

天祝县牧区开地示范工程项目１９９５年由农业部和国家计委审批立项,１９９６年全面启动建设,该项目以良种繁育,疫病防治,草地建设,技术服务四大体系为主体建设内容,并于１９９８年８月通过验收,围栏是草地建设体系的主要建设内容,在突出生产性,公益性,基础性建设原则的基础上,自１９９６年以来累计建成４０００ｈｍ＾２建成后,经综合改良,使草地植被得以迅速恢复,平均增产鲜草１６５３ｋｇ／ｈｍ＾２,年创经济效益３     

氟对牛脾淋巴细胞膜ATP酶活性的影响

取健康牛脾脏,常规方法分离培养淋巴细胞,用不同浓度氟化钠（NaF）染毒24h。低渗溶胞法提取细胞膜,检测膜上ATP酶活性。结果显示,与对照组相比较,染氟组淋巴细胞膜ATP酶活性降低,组间差异显著或极显著。表明：氟能抑制牛脾淋巴细胞膜ATP酶活性。