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截短侧耳素类抗生素研究进展 总被引：2，自引：0，他引：2
截短侧耳素（pleuromutilin）是高等真菌担子菌刚侧耳属pleurots mutilus和pleurots passeckerianus菌种经深层培养产生的一种抗生素,属双萜类化合物,主体骨架是由五元、六元和八元环拼合而成（截短侧耳素及其上市化合物结构见图1）,分子式为C22H24O5,相对分子量为378．51,熔点167—168℃。在水中微溶,在乙醇、丙酮以及乙醚中易溶。截短侧耳素及其衍生物可在核糖体水平上抑制细菌蛋白质的合成,对许多革兰氏阳性菌及支原体（Mycoplasma）感染有独特疗效。 相似文献
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硫粘菌素(Tiamulin)最早系从担子苗的侧耳属菇(Pleurotus.sp.)获得的抗菌素,称为截短侧耳素或脆柄菇素B(Pleuromulin).硫粘菌素系截短侧耳素的合成衍生物.其化学名为 14-脱氧-14-[(2-二乙基氨基乙基)疏基乙酰氧基]妙特灵[14-desoxy-14-[(2-diethylaminoethyl)mercaptoacetoxy]mutilin]. 相似文献
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研究截短侧耳素的萃取和结晶。截短侧耳素闪蒸粉分别用甲醇、乙醇和K酮在20℃、40℃和60℃条件下萃取,萃取时间60min,比较萃取率;60℃的K酮饱和溶液,分别降温至50℃、45RE和40℃,加入晶种保温3h,然后以5-8℃／h的速度降温至0℃,然后保温2h,离心获得晶体,50℃干燥1h,获得截短侧耳素粉,分析干燥失重、含量、杂质和收率。K酮在60℃时的萃取率最高,均值为92％;40℃加入晶种保温3h获得产品收率最高95．01％。K酮为更加理想的截短侧耳素萃取剂,萃取温度60℃,晶体成长的第一过程选择40℃。 相似文献
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新型磺胺类截短侧耳素衍生物抑菌效果研究 总被引：1，自引：0，他引：1
新型磺胺类截短侧耳素衍生物抑菌效果研究 《畜牧与饲料科学》2015,36(2):57-57
为研究新型磺胺类截短侧耳素衍生物对金黄色葡萄球菌和大肠杆菌的抑菌活性,采用纸片扩散法,用截短侧耳素和磺胺嘧啶作比较,通过测定抑菌圈大小进行判断。结果表明,新型磺胺类截短侧耳素衍生物对金黄色葡萄球菌和大肠杆菌均有抑制作用。 相似文献
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新型动物专用抗生素-沃尼妙林的研究进展 总被引：1，自引：0，他引：1
沃尼妙林（Valnemulin）是新一代截短侧耳素（pleuromutilin）类半合成抗生素,属二萜烯类,是泰妙菌素的同类药物。1984年,瑞士Sandoz公司13emer等利用截短侧耳素率先合成成功。1999年,瑞士Norvatis公司将其做成预混剂,商品名Eeonor,现已在多个国家上市．主要用于防治畜禽支原体及肠道螺旋体感染。由于沃尼妙林具有安全、高效、低毒、不易产生耐药性等特点,目前许多国家已广泛使用。本文就该药相关研究情况作一综述。 相似文献
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半胱胺盐酸盐对仔猪胃黏膜细胞H+-K+-ATPase活性和生长抑素表达的影响 总被引：1，自引：0，他引：1
将分离的仔猪胃粘膜细胞分为4组，在含10％胎牛血清的DMEM高糖培养液中培养24h后，分别在新鲜的基础培养液中添加0（对照组）、0．001（低水平组）、0．01（中水平组）和0．1（高水平组）g／L的半胱胺盐酸盐，继续培养20h后收集细胞。测定细胞H^＋-K^＋-ATPase活性，同时用相对定量RT—PCR法测定细胞H^＋-K^＋-ATPase和生长抑素（SS）mRNA的相对丰度。结果表明：（1）低水平的半胱胺盐酸盐对H^＋-K^＋-ATPase的表达和活性没有影响（P〉0．05），但中、高水平的半胱胺盐酸盐显著提高了H^＋-K^＋-ATPase的表达和活性（P〈0．05），其中H^＋-K^＋-ATPase mRNA的相对丰度分别提高了36％和44％，H^＋-K^＋-ATPase活性分别提高了57％和53％。（2）低水平半胱胺盐酸盐对SSmRNA的表达没有影响（P〉0．05），中、高水平的半胱胺盐酸盐显著提高了SSmRNA的相对丰度（P〈0．05），提高幅度均为52％。以上结果提示半胱胺盐酸盐可增强体外培养的仔猪胃黏膜细胞H^＋-K^＋-ATPase的表达及活性，而这一作用可能由SS所介导。 相似文献
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Oxygen tension and medium supplements for in vitro maturation of bovine oocytes cultured individually in a chemically defined medium 总被引：3，自引：0，他引：3
The effects of adding cysteamine, EGF, and glucose as an energy substrate under low oxygen tension during in vitro maturation (IVM) were examined to find ways of improving the individual in vitro production (IVP) system in individually cultured bovine oocytes. The basic medium was mSOFaa containing 1 mg/ml polyvinyl alcohol. Immature oocytes were individually cultured in an IVM medium with 10 ng/ml EGF, 100 microM cysteamine, or EGF plus cysteamine under 20% or 5% O(2). Cleavage and blastocyst rates were significantly higher (P<0.05) in IVM culture was under 20% O(2) than in culture under 5% O(2). Under 5% O(2), neither EGF nor cysteamine improved embryonic development. The proportion of matured oocytes was significantly higher (P<0.05) in the presence of 1.5 mM glucose under 20% O(2) (68.6%), and 5.5 mM (66.7%) and 10 mM (65.5%) glucose under 5% O(2). The presence of 5.5 mM glucose significantly (P<0.05) increased the maturation rate compared with the absence of glucose, irrespective of addition of EGF and cysteamine. The addition of cysteamine alone in the maturation medium significantly (P<0.05) increased the intracellular GSH concentration in the oocytes. Also, under 5% O(2) cysteamine and/or EGF significantly (P<0.05) improved the proportions of penetrated oocytes, cleavage and blastocyst formation, which were similar levels to those of oocytes matured under 20% O(2). After vitrification, the re-expanding and hatching rates of blastocysts derived from the individual IVP system containing cysteamine under 5% O(2) were significantly (P<0.05) higher than those of blastocysts derived from the individual IVP system without cysteamine under 5% O(2) and the group IVP system under 20% O(2). The present study showed that a high glucose level (5.5 or 10 mM) was optimal in IVM culture under low (5%) oxygen tension. The addition of EGF and/or cysteamine to the maturation medium had no positive effect on nuclear maturation, but improved fertilizability, developmental competence and cryoresistance following vitrification, probably due to increased GSH synthesis during the IVM process. 相似文献
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半胱胺对生长肥育猪胴体品质的影响及其机理探讨 总被引：16，自引：0，他引：16
在生长肥育猪的生长期和肥育期日粮中分别添加 6 0mg/kg半胱胺和 75mg/kg半胱胺 ,经屠宰试验表明 :胴体瘦肉率提高 4 .6 3% (P <0 .0 5 ) ,胴体脂肪率降低 8.5 3% (P <0 .0 5 ) ,同时第 10肋背膘厚降低 10 .17% (P >0 .0 5 )。在日粮中添加半胱胺使血清中生长激素 (GH)和三碘甲腺原氨酸 (T3 )含量分别提高 2 4 .4 4 % (P <0 .0 5 )和 2 1.31% (P <0 .0 5 )。添加半胱胺能显著提高皮下脂肪激素敏感脂酶 (HSL)活力 38.2 3% (P <0 .0 5 ) ,有降低苹果酸脱氢酶、葡萄糖 6 磷酸脱氢酶、异柠檬酸脱氢酶活性的趋势。研究结果显示 ,半胱胺可能通过增加血清GH含量和提高HSL活力来影响胴体品质。 相似文献
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The aim of the present study was to investigate the effect of cysteamine on growth performance of preweaning piglets and gastric expression of ghrelin mRNA in vivo and in vitro. Twelve litters of newborn piglets were allocated randomly to control and treatment groups. From 15 d of age, piglets in the control group were fed basal creep diet, whereas the treatment group received basal diet supplemented with 120 mg cysteamine per kg of diet until weaning on 35 d of age. Body weight gain, creep feed consumption, and diarrhea rates were recorded, and gastric mucosal tissues were collected for quantifying mRNA expression. To evaluate the direct effect of cysteamine on gastric ghrelin expression, primary cultures of gastric mucosal cells isolated from 35-d-old piglets were exposed to cysteamine for 20 h at 0, 1, 10, and 100 μg/mL, respectively. Dietary cysteamine increased (P < 0.05) average daily creep feed consumption and BW gain in preweaning pigs, which was accompanied by reduction in diarrhea rates. At 35 d of age, piglets treated with cysteamine showed increased (P < 0.05) ghrelin and gastrin and decreased (P < 0.05) somatostatin mRNA expression in gastric mucosa. Moreover, dietary cysteamine treatment increased serum concentration of gastrin (P < 0.05). In vitro, cysteamine significantly increased ghrelin mRNA expression in gastric mucosal cells at the concentration of 10 μg/mL. In conclusion, dietary cysteamine is effective in improving the growth performance and health condition of preweaning piglets, which is associated with its stimulatory effects on gastric ghrelin mRNA expression both in vivo and in vitro. 相似文献
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Influence of Cysteamine on In Vitro Maturation, In Vitro and In Vivo Fertilization of Equine Oocytes
S Deleuze CS Dubois M Caillaud B Bruneau G Goudet G Duchamp 《Reproduction in domestic animals》2010,45(1):1-7
The effect of cysteamine on in vitro nuclear and cytoplasmic maturation of equine oocytes collected by transvaginal ultrasound guided follicular aspiration was assessed. Oocytes were matured in vitro with (cysteamine group) or without (control group) cysteamine. The nuclear stage after DNA Hoechst staining, penetration rates after two different in vitro fertilization (IVF) techniques (IVF media with ionophore and Hepes buffer with heparin) and the embryo yield following oocyte intra-oviductal transfer were used as a criterion for assessing nuclear and cytoplasmic maturation, respectively. Contrary to the data described in other domestic species, there was no effect of cysteamine on in vitro nuclear maturation, IVF or in vivo embryonic development under our conditions. Ovum pick up yields (52%) and maturation rates (control group: 47% and cysteamine group: 55%) were similar to those previously reported. From 57 oocytes transferred to the oviduct in each group, the number of embryos collected was 10 (17%) in the control group and five in the cysteamine group (9%). Those two percentages were not statistically different (p > 0.05). No effect of IVF technique was seen on the success rate (6%) in each group. 相似文献
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本试验旨在研究水牛饲粮中添加半胱胺对水牛泌乳性能、瘤胃发酵参数、抗氧化性能和瘤胃微生物组成的影响。选取体重（615 kg±21 kg）、胎次（3~5胎）和产奶量（6 kg/d±1 kg/d）相近的健康泌乳中期尼里-拉菲奶水牛20头,采用单因素随机区组设计,分为4组,每组5头水牛。在基础饲粮中分别添加0（对照组）、15、30和45 g/d半胱胺。预饲期1周,试验期4周。结果表明：与对照组相比,①添加半胱胺对水牛体表温度、直肠温度和呼吸频率均无显著影响（P>0.05）。②添加30和45 g/d半胱胺显著提高了水牛干物质采食量（DMI）和酸性洗涤纤维（ADF）表观消化率（P<0.05）。③添加半胱胺显著提高了水牛产奶量、4%乳脂校正乳产量、乳蛋白率、乳总固形物和乳非脂固形物含量（P<0.05）。④添加45 g/d半胱胺显著提高了水牛瘤胃微生物蛋白（MCP）含量（P<0.05）;添加半胱胺对水牛瘤胃液细菌和真菌数量无显著影响（P>0.05）;添加15 g/d半胱胺显著降低了原虫数量（P<0.05）,而半胱胺添加剂量为30 g/d时瘤胃液原虫数量则显著增加（P<0.05）。⑤添加半胱胺能显著降低乳中C14：1n5、C18：3n6含量,显著增加乳中C18：1n9t、C19：0、C20：3n6含量（P<0.05）。添加30 g/d半胱胺显著降低乳中C16：0、C18：0和饱和脂肪酸（SFA）含量（P<0.05）;添加30和45 g/d半胱胺显著降低乳中C20：4n6（ARA）和不饱和脂肪酸（UFA）含量（P<0.05）。⑥添加半胱胺组水牛血清总抗氧化能力（T-AOC）显著提高（P<0.05）;15和30 g/d半胱胺组水牛血清丙二醛（MDA）含量显著降低（P<0.05）;30和45 g/d半胱胺组谷胱甘肽过氧化物酶（GSH-Px）活性、总蛋白、球蛋白水平显著增加（P<0.05）;15和45 g/d半胱胺组皮质醇（Cor）显著降低（P<0.05）;30 g/d半胱胺组谷草转氨酶（AST）活性显著增加（P<0.05）。综合试验结果,饲粮中添加半胱胺能够提高泌乳中期水牛泌乳性能与抗氧化能力,影响水牛瘤胃发酵、乳脂脂肪酸含量和瘤胃原虫数量。在本试验条件下,建议半胱胺在水牛饲粮中的适宜添加量为30 g/d。 相似文献
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A Mukherjee D Kumar KP Singh MS Chauhan SK Singla P Palta RS Manik 《Reproduction in domestic animals》2010,45(6):1118-1121
Comet assay was used in the present study to examine DNA damage to buffalo oocytes and embryos during in vitro culture. Embryos were produced in vitro from oocytes obtained from slaughterhouse ovaries in presence of cysteamine (IVM and IVC media supplemented with 50 and 100 μm , respectively) or in its absence (controls). Compared to controls, cysteamine supplementation increased (p < 0.01) cleavage rate and proportion of oocytes that developed to 8‐ to 16‐cell stage. The incidence of DNA damage was lower (p < 0.01) in cysteamine group than that in controls at 8‐ to 16‐ (19.3 ± 4.24 vs 72.0 ± 5.22%) but not in 2‐cell stage embryos (11.7 ± 5.63 vs 20.8 ± 5.49%) or in mature oocytes (5.3 ± 3.43 vs 10.3 ± 4.73%). The tail length, which indicates magnitude of DNA damage, was shorter (p < 0.01) in cysteamine group than in controls in mature oocytes (25.5 ± 0.5 vs 36.0 ± 0.71 pixels) and 8‐ to 16‐cell stage (49.2 ± 1.64 vs 152.7 ± 1.28 pixels) but not in 2‐cell stage embryos (36.3 ± 1.54 vs 36.4 ± 0.75 pixels). Also, exposure of oocytes/embryos to UV radiation or H2O2 caused extensive DNA damage. In conclusion, these results suggest that oocytes/embryos suffer from DNA damage during progress of in vitro culture, which can be partly ameliorated by cysteamine supplementation of culture media. 相似文献
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本试验旨在研究半胱胺对冬毛期雄性水貂生产性能、营养物质消化率及氮代谢的影响。试验采用双因子试验设计,影响因素为半胱胺添加水平和添加方式。选取167日龄、体重相近的健康雄性水貂56只,随机分为7组,每组8个重复,每个重复1只。Ⅰ组(对照组)饲喂基础饲粮,Ⅱ、Ⅲ、Ⅳ组分别饲喂在基础饲粮基础上添加60、90、120 mg/kg半胱胺的试验饲粮,半胱胺添加方式为连续添加,Ⅴ、Ⅵ、Ⅶ组试验饲粮分别同Ⅱ、Ⅲ、Ⅳ组,半胱胺添加方式为间隔添加(连续添加1周,间隔1周)。预试期7 d,正试期51 d。结果表明:1)Ⅲ、Ⅴ、Ⅵ、Ⅶ组的平均日增重极显著高于对照组和Ⅳ组(P0.01),料重比极显著低于对照组和Ⅳ组(P0.01);间隔添加组的平均日增重、料重比极显著优于连续添加组(P0.01);90 mg/kg组料重比极显著低于120 mg/kg组(P0.01)。各半胱胺添加组的毛皮品质均有所改善,Ⅵ、Ⅶ组皮长及针毛、绒毛长度显著高于对照组(P0.05),间隔添加组针毛长度极显著高于连续添加组(P0.01),90 mg/kg组针毛长度显著高于60和120 mg/kg组(P0.05)。半胱胺添加水平和添加方式的交互作用对平均日增重、料重比及针毛、绒毛长度产生了显著或极显著影响(P0.05或P0.01)。2)各半胱胺添加组粗蛋白质消化率均极显著高于对照组(P0.01),干物质、粗脂肪消化率各组间无显著差异(P0.05)。3)各半胱胺添加组粪氮排出量较对照组显著或极显著降低(P0.05或P0.01),Ⅵ组氮沉积显著高于对照组及Ⅱ、Ⅳ组(P0.05),间隔添加组氮沉积、净蛋白质利用率、蛋白质生物学价值较连续添加组显著升高(P0.05)。由此可见,饲粮添加半胱胺能够促进冬毛期雄性水貂的生长,并提高毛皮品质、营养物质消化率及氮代谢。综合考虑各项指标,在本试验条件下,冬毛期雄性水貂饲粮中半胱胺的最适添加水平为90 mg/kg,添加方式为间隔添加(连续添加1周,间隔1周)。 相似文献
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Cooper DV Grobler D Bush M Jessup D Lance W 《Journal of the South African Veterinary Association》2005,76(1):18-21
A combination of thiafentanil (A3080), medetomidine hydrochloride (MED) and ketamine hydrochloride (KET) was evaluated in 19 boma-habituated (12 female and 7 males) and 9 free-ranging nyala (7 male and 2 females) (Tragelaphus angasi) to develop a safe and reliable anaesthesia protocol. Wide dosages were used safely during this study with ranges for A3080 of 45 +/- 8 microg/kg with MED of 69 +/- 19 microg/kg and KET of 3.7 +/- 1.0 mg/kg (200 mg/ animal). The dosages developed on boma-habituated nyala proved to be equally effective in 9 adult free-ranging nyala (7 males and 2 females). The optimum dosage for nyala was a combination of A3080 (40-50 microg/kg), MED (60-80 microg/kg) plus 200 mg of KET/animal. The anaesthesia was characterised by a short induction, good muscle relaxation and mild hypoxaemia during monitoring the anaesthesia was rapidly and completely reversed by naltrexone hydrochloride (30 mg/mg of A3080) and atipamezole hydrochloride (5 mg/mg of MED) given intramuscularly. There was no mortality or morbidity associated with this protocol. 相似文献