A sub-population of circulating porcine gammadelta T cells can act as professional antigen presenting cells

A sub-population of circulating porcine gammadelta T cells express cell surface antigens associated with antigen presenting cells (APCs), and are able to take up soluble antigen very effectively. Functional antigen presentation by gammadelta T cells to memory helper T cells was studied by inbred pig lymphocytes immunised with ovalbumin (OVA). After removing all conventional APCs from the peripheral blood of immunised pigs, the remaining lymphocytes still proliferated when stimulated with OVA. When gammadelta T cells were further depleted, OVA specific proliferation was abolished, but reconstitution with gammadelta T cells restored proliferation. The proliferation was blocked by monoclonal antibodies (mAb) against MHC class II or CD4, and by pre-treatment of gammadelta T cells with chloroquine. These results indicate that a sub-population of circulating porcine gammadelta T cells act as APCs and present antigen via MHC class II.     

催乳素对内蒙古绒山羊毛囊体外培养影响的研究

【目的】 研究催乳素（PRL）对内蒙古绒山羊初级毛囊和次级毛囊体外生长及形态变化的影响。【方法】 机械法结合切割法分离内蒙古绒山羊的初级毛囊和次级毛囊,在初级毛囊培养液中分别添加0、5、10、50、100 ng/mL催乳素进行体外培养,每组24根,共培养5 d,每天在显微镜下观察其形态并拍照,统计其生长长度、生长速度和存活率,筛选出最适催乳素处理浓度。然后将初级毛囊与次级毛囊分别分为初级毛囊对照组（PF-K）、初级毛囊试验组（PF-PRL）、次级毛囊对照组（SF-K）、次级毛囊试验组（SF-PRL）,每组24根,对照组用基础培养液培养,试验组在基础培养液中添加最适浓度的催乳素,培养5 d,每天观察毛囊的形态并拍照,同时测量各组毛囊的生长长度。【结果】 10 ng/mL催乳素组毛囊的平均日生长长度均极显著高于其他浓度组（P<0.01）,最终生长长度和存活率均最高,因此,后续试验选择10 ng/mL催乳素处理毛囊。试验组和对照组初/次级毛囊的毛干与根鞘部位同时伸长,随着培养时间的增加均出现不同程度的弯曲。PF-PRL、SF-PRL组毛囊在2~5 d的总长度分别极显著高于PF-K、SF-K组（P<0.01）。PF-K组除第1天与第0天差异不显著外,1~5 d毛囊的总长度依次显著增加（P<0.05）;PF-PRL组0~5 d毛囊的总长度依次显著增加（P<0.05）。SF-K组毛囊第5天的总长度显著高于0~4 d （P<0.05）;SF-PRL组第4、5天毛囊的总长度均显著高于0~3 d （P<0.05）,第3天毛囊的总长度显著高于0~2 d （P<0.05）。PF-PRL、SF-PRL组毛囊在2~5 d的平均日生长长度分别极显著高于PF-K、SF-K组（P<0.01）。【结论】 10 ng/mL催乳素是体外促进毛囊生长的最适浓度,10 ng/mL催乳素对体外培养的内蒙古绒山羊的初级毛囊和次级毛囊均有极显著的促生长作用。     

巴美肉羊发情期外周血E2和P4浓度变化规律与排卵数关系研究

绵羊在发情周期中各生殖激素浓度变化与卵泡发育、成熟和排卵有着密切的关系。为了研究巴美肉羊血清生殖激素的动态变化及其与排卵数关系,试验采用电化学法,测定了12只成年母羊发情期血清中2种类固醇激素(E₂和P₄)的浓度水平,分析其动态变化规律,并用SAS 9.0的方差分析程序分析激素浓度与排卵数的关系。结果表明,两种激素在排单卵组和排双卵组绵羊间变化规律不同,E₂在排单卵组表现为先下降后升高的变化趋势,在排双卵组表现为持续下降趋势;P₄在排单卵组表现为持续上升的趋势,在排双卵组为先上升后下降的变化趋势。排单卵和排双卵组绵羊在各时间点的E₂和P₄激素浓度差异均不显著(P＞0.05)。     

The Expanding Role of Recombinant Gonadotropins in Assisted Reproduction

Using recombinant gonadotropins for assisted reproduction of domestic species is still in its infancy. Yet, the purity, potency and pathogen-free nature of recombinant gonadotropins make them attractive alternatives to tissue-derived gonadotropic agents. In this study, the authors summarize the work to date using recombinant gonadotropins to enhance the - fertility of domestic animals and they discussed their recent studies examining the biopotency of single chain analogues of human gonadotropins. In these studies, single chain analogues of follicle stimulating hormone (Fcα), chorionic gonadotropin (CGβα) or a gonadotropin construct with dual activity (FcCGβα) were administered to sheep pre-treated with antisera directed against GnRH. Ovulation was induced 3 days after analogue administration using hCG (1000 IU, iv). Although Fcα or CGβα alone induced only modest oestradiol production during the pre-hCG period, serum concentrations of oestradiol were markedly increased (p < 0.05) 3 days after administration of FcCGβα or the Fcα + CGβα combination. Final ovarian weight was significantly increased (p < 0.05) in animals receiving Fcα, Fcα + CGβα or FcCGβα. Collectively, these observations demonstrate that the single chain analogues of the human gonadotropins are active in sheep.     

Suppression of ovarian progesterone production in dairy cows using an implant of GnRH-agonist (deslorelin) for the purpose of evaluating progesterone metabolism

OBJECTIVE: To evaluate the potential of an implant of a GnRH-agonist (deslorelin) to create a progesterone free animal suitable for studying progesterone (P4) metabolism in intact cows by measuring blood P4 and faecal P4 metabolites. METHODS: Experiment 1: Eighteen non-lactating cycling Holstein-Friesian cows, 4 to 7 years old, were allocated to one of three groups to study plasma P4 concentrations preceding an intravaginal insert. These groups comprised: i) a deslorelin group (GnRH-agonist implanted); ii) a PGF group receiving two injections of prostaglandin (PGF2alpha) 12 days apart; and, iii) an ovariectomised (OVX) group. An intravaginal device (CIDR) was inserted into the vagina of each animal and left in place for 11 days. Plasma P4 concentrations were measured during the study period. Experiment 2: Twelve non-lactating cycling Holstein-Friesian cows, 4 to 7 years old, were allocated to two groups: i) a deslorelin group (GnRH-agonist implanted); and ii) an ovariectomised group. Plasma P4 and faecal P4 metabolites (20-oxo-pregnanes, 20alpha-OH and 20beta-OH) were monitored for a period of 5 weeks. RESULTS: Experiment 1: Average plasma P4 concentration did not differ between the three groups (1.28, 1.43 and 1.55 ng/mL for deslorelin, OVX and PGF cows, respectively, P = 0.8) during the period of supplementation. Experiment 2: There was no difference in plasma P4 (mean plasma P4 < 0.02 ng/mL, P = 0.9) and faecal P4 metabolites between deslorelin and OVX cows 2 weeks after the implantation (P = 0.7). CONCLUSIONS: These data showed that a GnRH-agonist (deslorelin) implant may be used as an alternative to ovariectomy to create a progesterone free animal suitable for studying the metabolism of administered P4.     

蓟马取食对苜蓿氨基酸组成及含量的影响

为了探究蓟马取食对苜蓿(Medicago sativa L.)氨基酸组成及含量的影响,本研究以'草原2号'(Medicago varia Martin.'Caoyuan No.2')感蓟马品种和'草原4号'(Medicago sativa L.'Caoyuan No.4')抗蓟马品种为材料,分别进行牛角花齿蓟马(Odo...     

Aggresomes and autophagy generate sites for virus replication

The replication of many viruses is associated with specific intracellular compartments called virus factories or virioplasm. These are thought to provide a physical scaffold to concentrate viral components and thereby increase the efficiency of replication. The formation of virus replication sites often results in rearrangement of cellular membranes and reorganization of the cytoskeleton. Similar rearrangements are seen in cells in response to protein aggregation, where aggresomes and autophagosomes are produced to facilitate protein degradation. Here I review the evidence that some viruses induce aggresomes and autophagosomes to generate sites of replication.     

中国蒙药资源可持续利用现状和对策

蒙药是蒙医师用于防治疾病的药物,是蒙医药事业发展的物质基础。蒙医药事业的可持续发展必须保障药材的质量和供应。随着蒙药资源使用量的增加和蕴藏量的减少,蒙药资源的可持续利用显得越来越重要。因此,一定要重视蒙药资源的可持续利用研究。文章着重介绍了蒙药资源可持续利用情况。     

Passive Immunity Stimulated by Vaccination of Dry Cows with a Salmonella Bacterial Extract

Background

Diarrhea because of Salmonella infection is a cause of neonatal calf diarrhea. The stimulation of passive immunity in the calf by vaccinating the dam for Salmonella has shown some success in previous studies; however, there are no data on the use of currently licensed vaccines in the United States.

Objective

To determine whether vaccinating cows at dry‐off with a commercially available Salmonella bacterial extract would stimulate Salmonella‐specific antibodies in the colostrum of cows at calving and whether these antibodies would be transferred to the calf.

Animals

Sixty Holstein cattle and 59 calves from a herd presumed to be naïve to Salmonella.

Methods

Prospective clinical trial. Thirty cows were vaccinated at dry‐off with a Salmonella enterica serovar Newport bacterial extract and again 4 weeks later. An additional 30 cows received only saline. Calves fed fresh colostrum from their dam within 4 hours of birth had blood collected 24 hours later.

Results

Vaccinated cattle had increased Salmonella Newport antibody titers at calving in blood (P = .01) and colostrum (P = .011). Calves that received colostrum from vaccinated cattle also had significant increase in Salmonella antibodies (1.04 ± 0.03) as compared to calves born to unvaccinated cows (0.30 ± 0.02).

Conclusions and Clinical Importance

The results indicate that the use of a commercially available Salmonella vaccine can stimulate antibodies that are passed on to the calf via colostral transfer. Further studies need to be done to determine whether these antibodies will offer protection against Salmonella challenge.     

海拉尔东山达乌尔黄鼠种群结构研究

采用标志重捕法在海拉尔东山上捕捉达乌尔黄鼠,确定年龄(根据牙齿磨损程度)、性别、数量,编制静态生命表以推测种群发展动态.研究表明,该地区中Ⅰ龄鼠占66.7％、Ⅱ龄鼠占20％、Ⅲ龄鼠占13.3％,年龄结构呈金字塔型,属于增长型种群,群体雄雌比例为1∶1.14,接近1∶1,种群中雌性略大于雄性.