金属硫蛋白及其抗应激功能

金属硫蛋白（MT）是一类富含半胱氨酸的低分子量金属结核蛋白，本文通过对金属硫蛋白（MT）的概述，介绍了金属硫蛋白的理化性质，逐个分析了能诱导金属硫蛋白合成的因素，并就金属硫蛋白主要生物学功能作了详细的说明。     

动物细胞内锌稳衡调节的研究进展

锌是生命必需的微量元素,参与了细胞内许多不同的代谢过程。对生物体而言,细胞内锌的稳态平衡非常重要。维持细胞内锌稳态平衡的蛋白主要包括金属硫蛋白(MT)及Zn转运蛋白(ZnTs)。本文主要介绍了MT及ZnT对锌稳态平衡的调节及锌对二者基因表达的调节作用。     

金属硫蛋白及其与动物应激的关系

本文就金属硫蛋白的性质,应激对金属硫蛋白合成的诱导,金属硫蛋白对应激的保护作用及其机制等问题做了探讨,并分析了金属硫蛋白在动物养殖业中的应用前景。     

微量元素锌的吸收、代谢及金属硫蛋白基因表达

本文通过分析锌吸收、代谢与金属硫蛋白(MT)的关系,表明锌可以直接调控金属硫蛋白基因表达,而金属硫蛋白的生物合成诱导也将调节体内锌的吸收、代谢,维持体内锌的稳态,为从分子水平研究锌的营养提供参考.     

金属硫蛋白与动物应激

金属硫蛋白是一类低分子量、富含半胱氨酸的金属结合蛋白,它与应激及应激性疾病有关。文章就应激对金属硫蛋白合成的诱导,金属硫蛋白对应激的保护作用及其机制等问题做了简单介绍,说明金属硫蛋白在动物养殖业中具有广阔的应用前景。     

镉中毒机理研究进展

镉通过与酶类巯基结合或替代作用,置换出细胞内酶类金属,降低机体抗氧化酶的活性,使机体清除自由基的能力下降,引起氧化损伤;镉可以占据钙离子通道并进入细胞内,使细胞内钙稳态失衡,也可在进入细胞前与细胞表面的孤儿受体上的抗原决定簇胞外锌位点结合,干扰细胞钙代谢;镉能诱导金属硫蛋白的形成,金属硫蛋白参与了镉在机体内的吸收、转运、排泄和蓄积;镉能引起DNA单链断裂,并损害DNA修复系统,导致细胞凋亡。由于镉致机体损伤的机制较为复杂,加之研究者采用的手段差异,影响了人们对其毒性机理的深入探讨。     

金属硫蛋白及其诱导、分离纯化研究进展

<正>金属硫蛋白(Metallothionein,MT)是一种广泛存在于生物界的低分子量、高金属含量,且能被金属或其它因素诱导生成的金属结合蛋白的一种天然生物活     

益生菌诱导合成金属硫蛋白及其对自由基清除率和安全性的实验

本文旨在介绍一种用益生菌诱导合成金属硫蛋白的方法,并观察其对羟自由基和氧自由基的清除率和在动物体中的安全性。通过对产朊假丝酵母用2.0mmol/lCuCl2进行诱导之后,经超声波进行破碎用结晶紫分光光度法和AP-TEMED法测定对羟自由基和氧自由基的清除率;用小白鼠通过灌胃的方法观察此法诱导合成的金属硫蛋白对动物体的安全性。结果显示,产朊假丝酵母合成的金属硫蛋白对羟自由基和氧自由基有很好的清除作用,分别达到了91.75%和83%。通过用小白鼠进行安全性实验证明此法诱导合成的金属硫蛋白安全无毒副作用,并且对增重还有一定的效果。     

金属硫蛋白及其在养殖业中的应用前景

金属硫蛋白是一类广泛存在于生物中的低分子量、富含金属和半胱氨酸的金属结合蛋白,具有重金属解毒、调节机体应激反应以及必需微量元素代谢等功能,因而它成为了近年来的研究热点.本文简要综述了金属硫蛋白的理化性质、生理功能及其在动物营养代谢和维持畜禽健康中的作用,并展望了金属硫蛋白在现代养殖业中的应用前景.     

金属硫蛋白与应激反应

金属硫蛋白(MT)是一类低分子量,富含半胱氨酸,可以被金属、氧化剂、细胞因子和糖皮质激素等多种因素诱导的蛋白质。它参与多种应激反应,被誉为一种多功能的"应激蛋白"。本文就MT在各种应激反应中的产生、调控及发挥的功能进行了重点阐述。     

Auricular chondritis caused by metal ear tagging in C57BL/6 mice

Although it has been shown that auricular chondritis in rats is caused by the use of metal identification ear tags, the pathogenesis remains unclear. Based on the hypothesis that the auricular chondritis is caused by metal ions released from metal identification ear tags, we investigated the pathogenesis in male C57BL/6 mice tagged with metal identification ear tags. Twenty-six weeks after the attachment of the ear tags, visible increases in the thickness of the auricle were observed, and the concentrations of copper and iron in the tagged ears were significantly increased (P < .05) in the tagged ears compared with the untagged ears. There was up-regulation of metallothionein (MT)-I and MT-II mRNA in the tagged ears, and this was confirmed by immunohistologic staining of the destroyed cartilage. Histopathologically, there were observed severe chondritis with extensive granulomatous inflammation, newly formed cartilage nodules, and osseous metaplasia accompanied by cellular infiltrates, such as CD4 T lymphocyte, macrophages, neutrophils, and mast cells, and expression of Th1 cytokines, such as interferon-gamma, tumor necrosis factor-alpha, and interleukin-2 in the tagged ear. Based on these results, we concluded that the release of copper and iron ions from the metal ear tags played a major role in the onset of auricular chondritis. Subsequent cellular interactions, such as CD4 T cells, macrophages, fibroblasts, and mast cells, mediated by cytokines, such as tumor necrosis factor-alpha and interferon-gamma, caused an autoimmune response that may have led to the progression of auricular chondritis as an autoimmune disease.     

金属硫蛋白及其在养殖业中的应用前景

金属硫蛋白是一类广泛存在于生物中的低分子量、富含金属和半胱氨酸的金属结合蛋白，具有重金属解毒、调节机体应激反应以及必需微量元素代谢等功能，因而它成为了近年来的研究热点。本文简要综述了金属硫蛋白的理化性质、生理功能及其在动物营养代谢和维持畜禽健康中的作用，并展望了金属硫蛋白在现代养殖业中的应用前景。     

金属硫蛋白生物学功能研究进展

金属硫蛋白是一类广泛存在于生物界的低分子量富含半胱氨酸的金属结合蛋白,因其独特的生物学功能,近年来国内外对金属硫蛋白各方面的研究日益受到重视.论文对金属硫蛋白参与体内微量元素储存、运输和代谢的作用,以及解重金属中毒、清除自由基和参与应激反应等生物学功能,金属硫蛋白与一些遗传性疾病、神经退行性疾病和心血管疾病的关系进行了综述.同时,对金属硫蛋白在生物学领域、医学保健领域、转基因工程领域、环境检测标志物和疾病防治等方面的应用前景进行了展望,并提出了金属硫蛋白研究中存在的问题及今后研究的方向.     

Intracellular distribution of copper and zinc in the liver of copper-exposed cattle from northwest Spain

The intracellular distribution of copper (Cu) and zinc (Zn) in the livers of normal and moderately Cu-exposed cattle was investigated with the aim of improving understanding of the pathophysiology of Cu accumulation in cattle. At total liver Cu concentrations within the generally accepted normal range (25-100 mg/kg fresh weight) the large-granule fraction was the main subcellular compartment for Cu accumulation, followed by the cytosol and the nucleus, whereas in the microsomal fraction Cu accumulation was very low. With increasing Cu exposure, the capacity of the large-granule fraction to accumulate Cu decreased, proceeding towards a plateau (estimated at about 80 mg/kg at a projected total liver Cu concentrations of 450 mg/kg), accompanied by progressively greater Cu accumulation in the nucleus and cytosol. Total liver Cu concentration had little influence on subcellular Zn distribution, with hepatic Cu concentrations being only moderately correlated with Zn concentration in the large-granule fraction. There was a strong association between the proportion of total Cu bound to metallothionein (MT) and the proportion of total Zn in the large-granule fraction, suggesting that Zn displaced from MT is taken up by the lysosomes for excretion. This pattern of Cu accumulation, as in sheep, may be due to the limited capacity for metallothionein binding of Cu and excretion in bile.     

金属螯合剂对延边黄牛体细胞核移植重组胚发育的影响

由于在核移植试验中,所用的水和化学物质都不可避免的会被一些金属离子轻微污染,造成胚胎内抗氧化物和过氧化物之间难以保持平衡,从而导致胚胎发育率降低,本试验以此为出发点,探讨了在延边黄牛体细胞核移植重组胚早期培养液中添加乙二胺四乙酸钠（EDTA-Na）和柠檬酸钠（sodium citrate）2种金属螯合剂类抗氧化剂,对其后续发育的影响,以期筛选出最佳的体外培养条件。结果表明：适合延边黄牛体细胞核移植重组胚后期发育的EDTA-Na和柠檬酸钠的最佳浓度分别为50μmol/L和0.6mmol/L。     

The evaluation of the potential of botulinum C3 enzyme as an exogenous differentiation inducing factor to neurons

Botulinum C3 enzyme produced by Clostridium botulinum type C and D strains modifies Rho proteins. In a previous study, we observed that the LDH isozyme pattern of neurons treated with C3 enzyme was different from that induced with endogenous growth factor of neurons such as NGF [21]. This type of change is considered to have an advantage in the medical use of C3 enzyme for neural disorder. To determine the functional similarity of C3-treated neurons to control and NGF-treated neurons, we examined the responses of C3-treated neurons to various drugs, including some neurotransmitters, by measuring the rise of intracellular Ca ions into the neurons. The time course of the rise of intracellular Ca ions induced by high concentration of potassium in the C3-treated neurons was similar to that in the NGF-treated neurons. The C3-treated neurons responded to glutamic acid, aspartic acid, kainic acid, gamma-aminobutylic acid, muscarine and ACh with similar time courses and magnitudes as the control neurons. These results suggest that the C3 enzyme induces the functional differentiation of neurons, and that C3 enzyme has the potential for the medical use as an exogenous differentiation-inducing factor of neurons.     

动物转录因子相关数据库研究进展

转录因子是真核生物中调控基因转录的一类重要的反式作用因子。目前,对动物群体的转录因子已经开展了较为深入的研究,科研人员不仅通过实验证实而且利用生物信息技术预测了全基因组范围内的转录因子,并基于上述数据构建了多个专用的二级数据库。概述了8个应用于动物群体的转录因子数据库,以期为进一步探明转录因子调控动物相关基因转录的分子机制提供理论基础。     

重金属离子单克隆抗体及免疫检测研究进展

重金属离子的免疫学检测是检测重金属离子的一种新方法,与传统检测方法相比,省时、便携、费用低、易操作,能用于重金属离子的现场快速检测。重金属离子的免疫检测分为多克隆抗体免疫检测和单克隆抗体免疫检测,包括荧光偏振免疫检测、酶联免疫吸附检测和免疫传感器检测。其中基于抗重金属离子—螯合剂复合物的单克隆抗体建立的免疫检测技术显示出很好的应用前景。