应用荧光原位杂交技术进行哺乳动物性别鉴定的研究进展

荧光原位杂交（FISH）技术应用于哺乳动物性别鉴定,近年来取得了长足进展。本文阐述了荧光原位杂交技术的原理及其在胚胎性别鉴定方面和精细胞筛选鉴定方面较PCR法和LAMP法所具有的优势,并着重概述了该技术在人类医学和家畜性别鉴定方面的研究进展和应用前景。     

谷胱甘肽和活性氧对哺乳动物配子作用的研究进展

文章综述了近年来关于谷胱甘肽对哺乳动物精子、卵母细胞和胚胎早期发育的作用及活性氧对精子功能的影响。在雄性和雌性配子中,谷胱甘肽起着保护精子和卵母细胞免受氧化损害的作用。在卵母细胞减数分裂中谷胱甘肽具有维持纺锤体形态的作用,受精后,巯基在精核的形成中起着积极的作用,并促进早期胚胎发育到囊胚阶段。在卵母细胞成熟过程中,谷胱甘肽的浓度发生着变化。它的合成受促性腺激素的调节,在精子的发生过程中随着精子的成熟,谷胱甘肽的浓度逐渐降低,但活性氧对精子功能也有多方面的作用。文章对卵丘细胞中小分子巯基化合物在谷胱甘肽合成中的重要作用也进行了综述。     

The Domestic Livestock Resources of Turkey: Status,Use and Some Physical Characteristics of Mules

Mules are known to have been used as carriage and riding animals in Mesopotamia and Anatolia as early as the beginning of the second millennium BC but may have been first bred in Anatolia in the Third Century BC. They have thus contributed to Turkey’s cultural, social and economic heritage for more than 4,000 years and were an ancient component of its guild of domestic animals and overall biodiversity. Once bred country-wide most mules are now introduced “illegally” to the southeast and east from Iraq and Iran. Mules are now bred only in one small area in north-central Turkey close to the Black Sea. The major role as a pack animal has been usurped since the mid-twentieth century by increasing use of motor transport and numbers have declined rapidly since the early 1980s. In 2009 about 51,500 mules remained in Turkey, mainly distributed in discrete areas in the extreme southeast, the centre-south, the northwest and the centre-north. In the southeast the main role is in cross-border trade (much of it described as smuggling) whereas in other areas mules are used in support of pastoral and farming operations. Mules in Turkey are of various colours but are generally large and strong compared to those found in many other countries. Pressure on numbers will continue and will exert a negative effect on a part of Turkey’s national heritage and domestic animal biodiversity.     

雌激素对哺乳动物卵泡发育的影响研究进展

雌激素在卵泡发育过程中所起的作用,已经得到人们的普遍认可。雌二醇(E2)及其类似物在卵泡的体细胞的增殖和分化中起重要作用,但其作用机理目前还不完全清楚。一些最新研究结果雌激素受体β(ERβ)的发现、雌激素受体基因敲除以及雌激素缺失动物模型的建立等,使我们能够进一步探讨雌激素在卵泡发育过程中的作用机理。结合这些最新研究动态,探讨雌激素在卵泡发育过程中的作用及雌激素对卵巢內的体细胞表型分化的影响。     

11类哺乳类和鸟类动物红细胞免疫功能的对比研究

应用红细胞Ｃ３ｂ受体花环（Ｃ３ｂＲＲ）和免疫复合物花环（ＩＣＲ）试验，证实鸽、鹌鹑、鹅、鹿、瘤牛、牦牛、德宏水牛（沼泽型水牛）、摩拉水牛（江河型水牛）、驴、小耳猪和山羊红细胞表面存在补体Ｃ３ｂ受体（Ｃ３ｂｒｅｃｅｐｔｏｒ，Ｃ３ｂＲ），表明红细胞免疫系统（Ｒｅｄｃｅｌｌｉｍｍｕｎｅｓｙｓｔｅｍ，ＲＣＩＳ）的概念亦适用于这１１类动物。文中对红细胞Ｃ３ｂＲＲ和ＩＣＲ分别代表红细胞表面Ｃ３ｂＲ“空位”和“占位”状态的会意做出了解释。对１１类动物中哺乳类与鸟类动物红细胞Ｃ３ｂＲＲ和ＩＣＲ测试的统计结果进行剖析，可知：总体上讲，３种鸟类红细胞表面补体Ｃ３ｂＲ活性显著小于８类哺乳动物（Ｐ＜０．０５，有少数例外），而红细胞粘附免疫复合物能力则极显著地大于８类哺乳动物（Ｐ＜０．０１）；红细胞粘附免疫复合物能力和其表面Ｃ３ｂＲ活性在不同动物种、型间有相当的差异。     

Differential ammonia metabolism and toxicity between avian and mammalian species,and effect of ammonia on skeletal muscle: A comparative review

Comparative aspects of ammonia toxicity, specific to liver and skeletal muscle and skeletal muscle metabolism between avian and mammalian species are discussed in the context of models for liver disease and subsequent skeletal muscle wasting. The purpose of this review is to present species differences in ammonia metabolism and to specifically highlight observed differences in skeletal muscle response to excess ammonia in avian species. Ammonia, which is produced during protein catabolism and is an essential component of nucleic acid and protein biosynthesis, is detoxified mainly in the liver. While the liver is consistent as the main organ responsible for ammonia detoxification, there are evolutionary differences in ammonia metabolism and nitrogen excretory products between avian and mammalian species. In patients with liver disease and all mammalian models, inadequate ammonia detoxification and successive increased circulating ammonia concentration, termed hyperammonemia, leads to severe skeletal muscle atrophy, increased apoptosis and reduced protein synthesis, altogether having deleterious effects on muscle size and strength. Previously, an avian embryonic model, designed to determine the effects of increased circulating ammonia on muscle development, revealed that ammonia elicits a positive myogenic response. Specifically, induced hyperammonemia in avian embryos resulted in a reduction in myostatin, a well‐known inhibitor of muscle growth, expression, whereas myostatin expression is significantly increased in mammalian models of hyperammonemia. These interesting findings imply that species differences in ammonia metabolism allow avians to utilize ammonia for growth. Understanding the intrinsic physiological mechanisms that allow for ammonia to be utilized for growth has potential to reveal novel approaches to muscle growth in avian species and will provide new targets for preventing muscle degeneration in mammalian species.     

α-酮戊二酸对肌肉蛋白质合成的影响

酮戊二酸(α-KG)是戊二酸的两种带酮基衍生物中的一种,是三羧酸循环的中间产物及谷氨酸脱氨基的酮酸产物。因此,其在葡萄糖代谢及氨基酸代谢的调控方面具有特殊的生物学功能。近年来研究表明,其参与肌肉蛋白质代谢主要与哺乳动物雷帕霉素靶蛋白(mTOR)及G-蛋白偶联受体(GPR)的激活密切相关。本文就α-KG的生理功能及其在体内的基本代谢过程,调控肌肉代谢及其信号通路的研究进展进行综述,为进一步推广α-KG在饲料生产中的使用及深入研究α-KG的分子机制提供参考。     

提高哺乳动物克隆效率的研究进展

体细胞核移植技术（somatic cell nuclear transfer,SCNT）又称为体细胞克隆技术,在生物医学、遗传修饰动物研究及大家畜的育种和良种扩繁等领域具有重要的理论意义和现实价值,但目前该项技术依然存在如克隆效率低下、克隆动物表型异常等问题。近年来,研究人员通过在培养基中添加小分子药物、选择优势供体细胞系（包括iPS细胞）、优化传统核移植参数、对发育关键基因（如XIST及H3K9me3去甲基化酶等）的靶向遗传调控等途径,探索提高克隆效率的新思路、新工艺和新方法,作者着重对上述研究进展进行简要综述。     

印记基因对哺乳动物胚胎和胎盘发育的调控机制

印记基因在调控哺乳动物的众多生命进程中发挥着重要作用,尤其是在生命形成初期,印记基因通过表观遗传修饰决定等位基因的表达和沉默,调节着胚胎和胎盘的生长发育。印记基因在胎盘和胚胎中的表达紊乱与胎儿生长受限、发育停止以及甲状腺脱毒症等密切相关,因此深入探索印记基因对胚胎和胎盘发育的调节机理对于哺乳动物胎儿宫内发育迟缓、出生缺陷以及后期疾病的预防具有重要的指导意义。本文综述了印记基因的主要特点、性腺中印记的擦除、重建与表观遗传修饰及印记基因调控哺乳动物胚胎和胎盘发育的最新研究进展。     

宇佐美曲霉木聚糖酶在哺乳动物细胞中的分泌表达

本试验旨在从宇佐美曲霉菌株GIM3.36中克隆得到木聚糖酶基因xyn的成熟肽编码序列(555 bp),并将其克隆到真核表达载体pcDNA6/His^TM A中的不同位置,分别得到重组质粒pcDNA-spna和pcDNA-spnb,重组质粒经过酶切、测序鉴定其读码框的正确性。在脂质体介导下将重组质粒转染猪肾细胞(PK15),通过RT-PCR证实其在PK15细胞中表达,并在细胞培养液中测定木聚糖酶酶活,结果显示,重组质粒pcDNA-spna转染细胞后表达的酶活力最高为8.53 U/mL,较pcDNA-spnb表达的酶活(6.87 U/mL)高24%,实现了微生物基因在哺乳动物细胞的分泌表达,为xyn基因在转基因方面的利用提供了依据。