白头翁素对RIMEC分泌功能的影响

目的：探讨白头翁素对细菌脂多糖（LPS）诱导的肠黏膜微血管内皮细胞（RIMEC）内皮素（ET-Ⅰ）和一氧化氮（NO）分泌增加的影响.方法：以体外培养的大鼠肠黏膜微血管内皮细胞（RIMEC）为试验模型,ET-Ⅰ测定采用酶联免疫技术,NO测定采用还原酶法.结果：白头翁素10 μg/ml、5 μg/ml、1 μg/ml预孵2 h加入1 μg/ml的LPS刺激12 h后.白头翁素组1 μg/ml ET-Ⅰ分泌显著低于LPS组（P＜0.05）,5 μg/ml、10 μg/ml白头翁素组ET-Ⅰ分泌极显著低于LPS组（P＜0.01）;10 μg/ml、5 μg/ml、1 μg/ml白头翁素组NO分泌极显著低于LPS组（P＜0.01） 结论：白头翁素可以下调LPS诱导的ET-Ⅰ和NO分泌增加,这可能是白头翁的抗炎机制之一.     

SLT-Ⅱe对PIMVECs分泌炎症反应相关细胞因子的影响

本试验旨在探究大肠杆菌志贺样毒素Ⅱ型变异体（SLT-Ⅱe）处理后,猪小肠微血管内皮细胞（PIMVECs）分泌的肿瘤坏死因子α（TNF-ɑ）、P选择素（P-selectin）、一氧化氮（NO）、细胞间黏附分子1（ICAM-1）和内皮素（ET）水平的变化。采用超速离心法提取SLT-Ⅱe,采用BCA试剂盒测定其质量浓度,使用SDS-PAGE及Western blotting验证蛋白纯度;用WST-1法从0.1、0.5、1、5、10 μg/mL SLT-Ⅱe和0、2、4、8、12、24 h中筛选出SLT-Ⅱe对PIMVECs最佳作用浓度与时间;ELISA法检测对照组（0 μg/mL SLT-Ⅱe）和试验组（1 μg/mL SLT-Ⅱe）细胞上清中TNF-ɑ、P-selectin、NO、ICAM-1和ET含量的变化。结果表明：所提蛋白为SLT-Ⅱe,蛋白含量为721.75 μg/mL;1 μg/mL的SLT-Ⅱe作用8 h后可极显著降低PIMVECs的活性（P<0.01）;1 μg/mL的SLT-Ⅱe作用9和12 h时PIMVECs的TNF-ɑ分泌量显著升高（P<0.05）,NO/ET的值显著高于对照组（P<0.05）,作用6、9、12 h时P-selectin的含量显著升高（P<0.05）,作用12 h时的ICAM-1分泌量显著升高（P<0.05）。综上所述,SLT-Ⅱe浓度为1 μg/mL时可以诱导PIMVECs分泌的TNF-ɑ、P-selectin、ICAM-1以及NO/ET上升,为研究仔猪水肿病发病机制提供参考。     

山楂、党参对鸭胰腺外分泌的影响

以北京鸭为试验动物,以手术的方法做胰-肠瘘管接取胰液。在生理条件下,分别测定北京鸭胰液总量、pH值、HCO-3、蛋白含量、淀粉酶活性、脂肪酶活性、蛋白酶活性等指标的昼夜变化规律。并观测了中药山楂(FructusCrataegi)、党参(RadixCodonopsispicosulae)在生理和阿托品阻断M受体的条件下对鸭胰液分泌的影响。结果表明:(1)在生理条件下,胰液7个指标的昼夜分泌规律各异。(2)在生理条件下,山楂可显著增加胰液分泌总量(P<0.05),并极显著地提高淀粉酶活性(P<0.01)。党参极显著地升高胰液的蛋白含量(P<0.01),显著地提高淀粉酶活性、脂肪酶活性(P<0.05)。提示山楂、党参的健脾消食作用是通过促进胰液外分泌来实现的。(3)用阿托品阻断M受体后,再用山楂,可显著增加胰液总量、蛋白含量、淀粉酶活性(P<0.05);用党参可显著升高胰液蛋白含量、淀粉酶活性,抑制脂肪酶、蛋白酶活性(P<0.05)。说明山楂、党参均可拮抗阿托品对胰液分泌的抑制作用。     

口蹄疫146S病毒粒子抗原对微血管内皮细胞分泌IL-1的影响

白介素1（IL-1）是免疫与炎症反应启动的重要调节因子。为了研究微血管内皮细胞（microvascular endothelial cells,MVECs）在口蹄疫病毒（foot and mouth disease virus,FMDV）免疫反应中的作用,本试验采用ELISA方法检测了FMDV 146S抗原对体外培养大鼠心肌膜MVECs分泌IL-1α和IL-1β的影响。研究结果发现,正常情况下大鼠心肌膜MVECs能够低水平的分泌IL-1α和IL-1β,FMDV 146S刺激后其分泌量显著增加。结果表明,MVECs通过上调IL-1分泌,在FMDV抗原的免疫反应中发挥重要的调控作用。     

应用Triton WK-1339测定产蛋鸡血脂分泌量的方法研究

通过研究不同剂量Triton WR-1339（TWR）对产蛋鸡血液脂肪（血脂）浓度的影响，探讨测定血脂分泌量的方法。选用15只24周龄、平均体重1．5kg的罗曼粉壳产蛋鸡，按单因子设计，分别从翅静脉注射4m LTWR，浓度分别为0、100、200、300mg／kg或400mg／kg体重（缓冲液为生理盐水）。每只产蛋鸡在注射TWR之前及注射后0．5、1、2、4、8、12、24、36h和48h从翅静脉采血，测定血清甘油三酯（TG）含量。结果表明：8h后注射TWR产蛋鸡的TG含量均显著高于注射生理盐水的产蛋鸡（P〈0．05），但36h后不同注射剂量下的TG含量又无显著差异（P〉0．05）。注射TWR产蛋鸡在0-8h的TG积累曲线均呈线性增加，到8h达最大值，此后逐渐下降。采食产蛋鸡血脂分泌量为0．1216mmol／（min&#183;kg体重）。静脉注射TWK 200-300mg／kg体重是研究产蛋鸡血脂分泌量的有效方法。     

复方蒲公英注射液解热镇痛抗炎作用研究

考察复方蒲公英注射液解热镇痛抗炎效果。解热试验取健康家兔10只,随机分为2组,每只兔背部皮下注射2,4-二硝基苯酚2%水溶液30 mg/kg,待体温升高超过1℃,分别按0.5 mL/kg腹腔注射生理盐水和复方蒲公英注射液,给药后30、60、90、120 min分别测量直肠温度;镇痛试验取昆明系小白鼠50只,随机均分为5组,分别为生理盐水组（0.05mL）、阿司匹林组（4%阿司匹林溶液0.05 mL）、复方蒲公英注射液低（0.05 mL）、中（0.1 mL）、高剂量组（0.2 mL）。连续经口给药3 d,于末次给药30 min后,每只小白鼠腹腔注射0.6%冰醋酸（0.1 mL/10 g）,记录注射致痛剂后20 min内各鼠的扭体次数;抗炎试验取昆明系小白鼠50只,随机分为5组,分别为生理盐水对照组（0.05 mL/10 g）、双黄连组（0.05 mL/10 g）、复方蒲公英低（0.05 mL/10 g）、中（0.1 mL/10 g）、高（0.2 mL/10 g）剂量组。连续腹腔注射给药5 d,在第5天注射后12 h,在小鼠右耳两侧均匀涂以二甲苯0.05 mL,左耳作为对照,2 h后处死,用直径0.5 cm打孔器取其左右耳片,称重,评价药物对二甲苯刺激耳廓的抗炎效果。结果提示,复方蒲公英注射液具有较好的解热抗炎作用,而无明显镇痛作用。     

中链甘油三酯对脂多糖刺激小鼠血液指标与肝脏抗氧化功能的影响

试验旨在研究中链甘油三酯(MCT)对脂多糖(LPS)刺激小鼠血液指标与肝脏抗氧化功能的影响。将40只昆明小鼠用2×2试验因子设计分成4组,主因子包括:日粮(10%豆油或"8%MCT+2%豆油")和免疫应激(注射LPS或生理盐水)。试验第28天,每个日粮组的5只小鼠注射150μg/kg体重的LPS,另5只注射无菌生理盐水作为对照。结果表明:与对照组相比,LPS显著降低了小鼠血浆葡萄糖、总蛋白水平及肝脏总抗氧化能力(P0.05),LPS刺激后小鼠血浆白介素-1β含量呈升高趋势(P=0.051);与长链甘油三酯(LCT)相比,MCT显著提高了血浆总蛋白、白蛋白含量(P0.05),并降低了总胆固醇水平(P0.05);MCT组血浆总甘油三酯(P=0.055)水平与肝脏总抗氧化能力(P=0.081)较LCT组呈升高趋势,肝脏丙二醛含量相对较低(P=0.091)。MCT降低了LPS刺激后小鼠机体葡萄糖的消耗,改善蛋白质代谢与肝脏抗氧化能力。     

采食后奶牛瘤胃短链脂肪酸及其吸收相关蛋白表达的研究

本试验旨在研究奶牛采食前后瘤胃中短链脂肪酸(SCFA)浓度的变化及其吸收相关蛋白表达量的差异。试验选用3头体重(720±30)kg且装有瘘管的健康荷斯坦牛(动物伦理审查编号为SXAU-EAW-2019-C002013),采食精粗比为40:60的日粮(10kg),试验预试期10d,于第11天饲喂前开始取样,采用气相色谱法检测奶牛采食前(0 h)和采食后(1、2、3、4、5、6、7、8 h)瘤胃液中SCFA浓度;并采用荧光定量PCR方法检测瘤胃上皮组织中与SCFA吸收相关的蛋白表达量。结果表明:在采食后1 h奶牛瘤胃中SCFA浓度最高(P<0.05);在采食后一段时间内(2~5h)与SCFA吸收相关蛋白表达量上调(P<0.05),AE2、MCT1基因表达量均在5 h最高,PAT1、NHE3基因表达量均在4 h最高,MCT4基因表达量在4、5、6h均较高,NHE1基因表达量在2h达到最高;AE2、MCT1、MCT4、NHE1基因表达量与SCFA浓度负相关或正相关(P<0.05),AE2、MCT1、MCT4基因表达量与瘤胃内pH正相关(P<0.05)。以上结果初步揭示,在采食后一定时间内,瘤胃中与SCFA吸收相关蛋白表达受SCFA浓度和pH的调节。     

灭活大肠杆菌与脂多糖诱导猪肠黏膜上皮细胞表达RegⅢγ的机理研究

试验旨在探索革兰氏阴性菌大肠杆菌（Escherichia coli,E.coli）及其表面分子脂多糖（LPS）诱导胰腺再生蛋白Ⅲγ（RegⅢγ）表达调控的机制。首先,用不同浓度灭活E.coli（10⁹、10⁸、10⁷、10⁶、10⁵、10⁴ CFU/mL）和LPS （0.01、0.1、1、5、10、20、40、80 μg/mL）诱导猪肠黏膜上皮细胞（IPEC-JⅡ）,用MTT法测D_{490 nm}值,检测E.coli和LPS对IPEC-JⅡ细胞活力的影响;其次,用不同浓度灭活E.coli（10⁷、10⁶、10⁵ CFU/mL）和LPS （0.01、0.1、1、5 μg/mL）处理IPEC-JⅡ细胞24 h,用实时荧光定量PCR和Western blotting检测RegⅢγ mRNA和蛋白的表达;最后,用1 μg/mL LPS处理IPEC-JⅡ细胞24 h,用实时荧光定量PCR和Western blotting检测p65、p38、JNK、ERK mRNA和蛋白表达及磷酸化水平。结果显示,除0.01 μg/mL LPS不抑制IPEC-JⅡ细胞活力外,其他浓度的灭活E.coli和LPS均可抑制IPEC-JⅡ细胞活力,且10⁹、10⁸ CFU/mL E.coli和10、20、40、80 μg/mL LPS组细胞活力极显著下降（P<0.01）;与对照组相比,10⁷、10⁶和10⁵ CFU/mL E.coli均能诱导RegⅢγ表达增加,且10⁵ CFU/mL E.coli组RegⅢγ mRNA表达量极显著高于对照组（P<0.01）,蛋白表达量显著高于对照组（P<0.05）;0.01、0.1、1和10 μg/mL LPS均能诱导RegⅢγ表达增加,且0.1和1 μg/mL LPS组RegⅢγ mRNA表达量极显著高于对照组（P<0.01）,RegⅢγ蛋白表达虽有增加趋势,但差异不显著（P>0.05）;与对照组相比,1 μg/mL LPS组p65、p38 mRNA表达量极显著增加（P<0.01）,JNK、ERK mRNA表达量显著增加（P<0.05）;同时,p38、JNK蛋白表达量和磷酸化水平均极显著增加（P<0.01）,p65蛋白磷酸化水平显著增加（P<0.05）,ERK蛋白和磷酸化水平均增加,但差异不显著（P>0.05）。以上结果表明,灭活E.coli和LPS均可诱导RegⅢγ表达,1 μg/mL LPS可增加p65、p38和JNK蛋白的磷酸化水平。     

催乳素通过酪氨酸激酶2/信号传导及转录激活蛋白5信号通路促进奶牛乳腺上皮细胞乳铁蛋白合成和分泌

本试验旨在研究催乳素（PRL）对奶牛乳腺上皮细胞（BMECs）中酪氨酸激酶2/信号传导及转录激活蛋白5(JAK2/STAT5)信号通路介导的乳铁蛋白（LF）合成和分泌的影响。添加不同浓度的PRL[0（对照）、10、100、1 000 ng/mL]处理BMECs 24 h,分析PRL对LF含量和LF、催乳素受体（PRLR）以及JAK2/STAT5信号通路基因表达量和相关蛋白表达的影响。为了验证STAT5在PRL促进BMECs LF合成和分泌的关键作用,添加STAT5抑制剂匹莫齐特（Pimozide）[未添加Pimozide（对照）、10μmol/L Pimozide、100 ng/mL PRL、10μmol/L Pimozide+100 ng/mL PRL]处理BMECs 24 h,测定PRL和Pimozide对LF含量和LF、JAK2/STAT5信号通路基因表达量和相关蛋白表达以及相对荧光强度的影响。结果表明：1）与对照组相比,10、100、1 000 ng/mL PRL能够显著或极显著提高BMECs上清液中的LF含量（P<0.05或P<0.01）;Pimozide组能够极...     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

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.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

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.     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

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.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein     

Evaluation of the Microbiological Status of Milk and Various Structures in Mammary Glands from Naturally Infected Dairy Cows

A knowledge of the microbiological status of milk and of the different structures in the mammary glands has great importance in elucidating the pathogenesis of mammary gland infections. The objective of this study was to evaluate the microbiological status of various structures in the mammary glands from naturally infected dairy cows following slaughter. A total of 94 samples of milk, 184 samples of mammary parenchyma, 168 samples of gland cisterns, and 168 samples of teat cisterns were collected for microbiological examination. Microorganisms were detected in 59.9% of all samples, 67.0% of the milk samples, 70.1% of the mammary parenchymas, 55.9% of the gland cisterns and 48.8% of the teat cistern samples. When all samples were considered, coagulase-negative Staphylococcus were the most prevalent (35.7%) followed by coagulase-positive Staphylococcus (12.2%), Corynebacterium bovis (2.4%), Prototheca sp. (1.9%), and Streptococcus dysgalactiae (1.5%). There was a significantly higher occurrence of microorganisms in the milk and mammary parenchyma compared to the gland cisterns and teat cisterns. This revised version was published online in July 2006 with corrections to the Cover Date.     

Development and survival of free-living stages of gastrointestinal nematodes of sheep and goats on pasture in the Nigerian derived savanna

Four grass plots were sequentially contaminated with goat faeces containing known numbers of unembryonated eggs of predominantly Haemonchus contortus and Trichostrongylus spp. between October 1982 and April 1983. Four other plots were similarly contaminated with sheep faeces between February and May 1987. An additional plot was repeatedly contaminated with sheep faeces from February to April 1987. Populations of free-living stages in faeces and of infective larvae (L₃) in the herbage were subsequently monitored until the end of April and June of 1983 and 1987 respectively. During February and May 1987 two control cultures of sheep faeces were incubated in the laboratory at 25°C–30°C and at a constant temperature of 50°C and the free-living development was also monitored. L₃ developed very readily in the faeces cultured at 25°C–30°C and in those spread on a grass plot in October, at the end of the wet season, but developed less on the plot contaminated in May at the start of the wet season. Worm eggs in faeces deposited on plots during the hot dry season (December to April) or incubated at 50°C died and disintegrated after 24–48 h exposure to the high environmental temperatures. The results indicate that it is unlikely that gastrointestinal nematodes of sheep and goats can develop or survive on open pasture during the dry season in the Nigerian derived savanna zone.