反义寡聚核苷酸：生理学研究中的新工具

反义寡聚核苷酸（antisenseoligonucleotide,AS-ON）通常是指与体内某RNA或DNA序列具有互补顺序,并能通过碱基配对与互补链杂交,从而影响其转录或翻译过程的核酸片段。AS-ONs技术的近来应用为生理学研究开辟了一条新路,对将来了解基因的功能提供了一种新手段。本文综述了AS-ONs的设计策略、作用机理、修饰和导入方式等基本问题,旨在对AS-ONs的应用提供参考。     

浅谈太极拳对老年人的健身养生功效

本文针对日益明显的人口老龄化问题,提出了太极拳对老年人健身机理的研究,提出太极拳对老年人生理、心理等方面良性的功效,让全世界更多的老人了解并受益于太极拳。     

单核苷酸多态性基因分型技术原理与进展

在基因组规模了解遗传变异与生物功能之间的关系可望为生物学带来全新的深入认识。本从等位基因分型机理、反应形式和检测方法等三个方面讨论SNP分型方法的现状,并简要介绍了目前应用的一些分型方法。     

蛋白水解酶在癌细胞迁移中的作用

癌细胞的迁移和侵袭是造成癌症患者死亡率居高不下的重要原因。研究表明癌细胞可以通过产生多种蛋白水解酶降解细胞外基质等机制参与癌细胞的迁移。本文主要阐述了几种蛋白水解酶对癌细胞细胞外基质的水解机理以及其临床应用。通过了解其机理为以后癌症的预防和治疗提供新的思路。     

肝脏类器官研究进展与应用

肝脏是人体重要的代谢器官,也是疾病高发器官。近年来,肝脏疾病发病率逐年上升,原发性肝癌已成为世界范围内癌症相关死亡的第二大病因。因此,深入了解肝脏生理机能,开发肝脏生理代谢及相关疾病致病机理研究的实验平台,寻找肝脏体外再生的新策略和方法,有望为肝脏疾病的发病机制研究、早期诊断和综合治疗提供新思路。该文主要围绕肝脏类器官的建立策略、主要应用和技术瓶颈等方面介绍肝脏类器官的最新研究进展,探讨其在解决肝脏研究领域若干重要科学问题的应用潜力。     

DNA疫苗研究现状和展望

自１９９２年第一次报道ＤＮＡ疫苗技术以来,在短短３－４年的时间内这一技术得到飞速发展,在ＤＮＡ疫苗的作用机理、如何增强ＤＮＡ免疫效果以及ＤＮＡ疫苗的优势和问题等方面做了大量卓有成效的探索,尽管现在人们对ＤＮＡ疫苗抗原提呈作用机理还不清楚,也还没有完全了解ＤＮＡ疫苗安全性问题,但是对ＤＮＡ疫苗的免疫防御、免疫治疗和免疫调节作用已有了较为清晰的认识。本文拟对此作一简要概述。     

酶制剂在畜牧及野生动物营养与饲养中的应用

从酶的化学本质、分类、功能、特性、作用机理及其应用现状等方面综述了酶制剂在家畜、家禽及濒危、经济野生动物营养与饲养中研究最新进展,并阐述了酶制剂研究应用存在问题和发展前景。     

RNA干扰技术的基础研究与应用

RNA干扰技术(RNAi)是一项高效率、强特异性的基因沉默技术.自1998年发现RNA干扰现象以来,RNAi吸引很多国内外科学家的研究兴趣.经过10多年的潜心研究,现在对该技术的参与成分、作用机理都有了较深入地了解.同时,随着生物学知识的完善和生物技术与基因工程的发展,研究人员时RNAi在基因功能研究、疾病(如肿瘤)相关的基因治疗、新药的研究与开发等方面的应用进行了广泛的探索,并且已经显示该技术的潜在应用价值,但是RNAi的自身缺陷制约了其在临床治疗等方面的实际应用.综述前人的研究结果,系统阐述了RNAi的发生、作用机理、缺陷以及其应用,为相关科学研究提供参考.     

对生理学发展的一点思考

近年来生理学的进展给人以极深刻的印象,从神经生理学等若干主要研究领域来看,除了历史性的叙述和某些基本的实验事实之外,自60年代以来,至少有50％以上的内容已经改写,研究的广度和深度更是今非昔比。新技术的应用、新资料的涌现、新概念的产生、新机理的提出,已经使人们对生理活动本质的了解焕然一新。这种前所未有的发展势头向我们提出了一系列值得深思的问题,其中最重要的是:生理学正在走向何处?我们应该怎样驾驭它的发展?     

动物模型在肺部真菌病研究中的应用

真菌病成为日益严重的临床问题,深部真菌感染尤其是肺部真菌感染呈持续增多趋势。肺部真菌病往往发生于免疫低下或有基础疾病的患者,其具体发病机制尚不完全清楚。动物模型不仅为真菌病病因学研究提供有效的途径,还能在抗真菌药物、免疫调节剂及可能的疫苗的研究中提供多方面的帮助。动物实验中所观察到的病理改变可能对发病机理的探索有所帮助。实验动物研究有助于我们明晰各种参数的作用机理,比如抗原、暴露途径、基因背景即反应修饰在发病中的作用,进一步的,通过基因缺失或插入或结合,我们有可能了解某种特定的细胞、受体、介质在发病过程中的机理,其结果可能应用到人类疾病上。     

Animal cloning applications and issues

Significant progress in the field of biotechnology has allowed for the use of cloning in animals which is being used: to improve genetic makeup, to rescue endangered species, in tissue engineering and to increase farm animal population. Unfortunately, cloning has been met with failure due to a variety of reasons namely early and late abortions, compromised immune systems, circulatory and respiratory problems and a high rate of fetal death. The reasons of these problems are unknown, but may research groups are attempting to understand the underlying molecular and cellular mechanisms involved in cloning efficiency. Atypical epigenetic re-programming appears to be the primary cause of ineffective cloning. Understanding molecular mechanisms involving key regulatory proteins is pivotal in the success of animal cloning. This review shows the current paradigm involving animal cloning efficiency, and also further elucidates applications to improve animal cloning efficiency.     

Progress toward generating a ferret model of cystic fibrosis by somatic cell nuclear transfer

Mammalian cloning by nuclear transfer from somatic cells has created new opportunities to generate animal models of genetic diseases in species other than mice. Although genetic mouse models play a critical role in basic and applied research for numerous diseases, often mouse models do not adequately reproduce the human disease phenotype. Cystic fibrosis (CF) is one such disease. Targeted ablation of the cystic fibrosis transmembrane conductance regulator (CFTR) gene in mice does not adequately replicate spontaneous bacterial infections observed in the human CF lung. Hence, several laboratories are pursuing alternative animal models of CF in larger species such as the pig, sheep, rabbits, and ferrets. Our laboratory has focused on developing the ferret as a CF animal model. Over the past few years, we have investigated several experimental parameters required for gene targeting and nuclear transfer (NT) cloning in the ferret using somatic cells. In this review, we will discuss our progress and the hurdles to NT cloning and gene-targeting that accompany efforts to generate animal models of genetic diseases in species such as the ferret.     

Klonen von Nutztieren. Tierzucht zwischen Landwirtschaft und Biomedizin

Somatic cloning in animal production The great success of animal production is primarily associated with the application of various reproductive biotechnologies, such as artificial insemination, embryo transfer, etc. Somatic cloning ist the most recent biotechnological method for which field application is emerging. Until today, somatic cloning has been successful in >15 different species. Current success rates, i.e. the production of live offspring, are still lower compared with conventionl production methods. However, worldwide research has led to significant improvements of the cloning technology which do allow field application for certain targets in cattle and pigs.     

转基因动物克隆技术的应用及生物反应器的建立

利用转基因克隆技术实现外源基因的导入宿主染色体基因组内稳定整合,并能遗传给后代,已在基因表达与调控的理论研究、人类遗传病动物模型的建立、药用蛋白的生产、抗病育种、人类移植用的器官的研究等方面得到广泛应用。转基因动物的研究与应用也已经成为21世纪生命科学领域最活跃、最具有实际应用价值的方向之一,尤其是作为生物反应器和医学上为人类提供所用器官方面,其经济价值和社会效益将是不可估量。在查阅大量近年来国内外相关资料的基础上,本文以转基因动物克隆为中心,对转基因动物克隆所采用显微注射技术、核移植技术、基因打靶与真核BAC表达载体制备等主要研究技术,以及转基因动物克隆在异种器官移植、构建生物反应器等方面的应用进行了综合性论述与分析,同时阐述了各种转基因技术的优点与缺点,以其为转基因动物克隆研究提供理论基础与技术支撑。     

供体细胞与哺乳动物体细胞核移植

哺乳动物体细胞核移植(克隆)技术在转基因动物生产、珍稀动物资源复原与保护、生物学基础研究等方面业已显示出重要的应用价值,而目前该技术还与诱导多能干细胞技术一同被认为是创制患者特异性多能干细胞,为再生医学临床"细胞治疗"提供素材的最佳手段。但是,体细胞克隆的效率仍不理想,关键机制还不清楚,严重制约了该技术的推广。因此,如何提高克隆效率已成为人们普遍关心的首要问题。在体细胞克隆技术所涉及的各环节中,供体细胞是影响克隆效率的最关键因素之一。该文从供体细胞的生物学因素和技术因素两方面进行了回顾,旨在为进一步探寻建立物种或供体细胞个性化准备方案,为提高动物克隆效率提供参考。     

Cloning and assisted reproductive techniques: influence on early development and adult phenotype

Over the past 40 years, our increased understanding and development of cell and molecular biology has allowed even greater advances in reproductive biology. This is most evident by the development of various aspects of assisted reproductive techniques (ART), generation of transgenic animals, and most recently generation of mammals through somatic cell cloning. To date, cloning from adult somatic cells has been successful in at least 10 mammalian species. Although generating viable cloned mammals from adult cells is technically feasible and the list of successes will only continue to grow with time, prenatal and perinatal mortality is high and live cloned offspring have not been without health problems. The success of many of the proposed applications of the cloning technique obviously depends upon the health and survival of founder animals generated by nuclear transfer. This article summarizes the health consequences of cloning in mice, and discusses possible mechanisms through which these conditions may arise. In addition, we discuss the effects of ART in animal models and in humans. ART also involves some of the same procedures used in cloning, and there are reports that offspring generated by ART sometimes display aberrant phenotypes as well. It is important to point out that although these techniques do sometimes produce abnormalities, the majority of offspring are born apparently normal and survive to adulthood. Additionally, we must emphasize that the effects of ART and cloning observed in animal models do not necessarily indicate that they will occur in humans. In this article, we review studies examining the phenotype of animals generated by cloning and various ART, and discuss clinical implications of these findings.     

Ethical issues in animal cloning

The issue of human reproductive cloning has recently received a great deal attention in public discourse. Bioethicists, policy makers, and the media have been quick to identify the key ethical issues involved in human reproductive cloning and to argue, almost unanimously, for an international ban on such attempts. Meanwhile, scientists have proceeded with extensive research agendas in the cloning of animals. Despite this research, there has been little public discussion of the ethical issues raised by animal cloning projects. Polling data show that the public is decidedly against the cloning of animals. To understand the public's reaction and fill the void of reasoned debate about the issue, we need to review the possible objections to animal cloning and assess the merits of the anti-animal cloning stance. Some objections to animal cloning (e.g., the impact of cloning on the population of unwanted animals) can be easily addressed, while others (e.g., the health of cloned animals) require more serious attention by the public and policy makers.     

鱼类核移植与重编程

鱼类核移植是动物克隆研究的一个重要领域, 我国学者在上世纪60年代首创了鱼类的核移植研究。以斑马鱼为模式动物, 进行核移植与再程序化研究具有独特的优势。文章总结了鱼类细胞核移植研究的历史、斑马鱼核移植研究概况、以及影响核移植胚胎发育的因素, 特别是核移植胚胎基因组的表观遗传修饰, 如基因组DNA甲基化及组蛋白乙酰化和甲基化等的研究, 将有助于完善克隆技术并提高克隆的成功率, 推动克隆技术的广泛开展和应用。     

核移植与治疗性克隆

核移植与治疗性克隆在畜牧业生产以及生物医学上具有广阔和诱人的应用前景。文章分析指出卵母细胞质量与供核细胞重新编程是影响体细胞核移植效率及克隆动物异常的主要因素,阐述了治疗性克隆所面临的一些基本问题及出路：治疗性克隆以核移植技术为基础,核移植所面临的一些问题也直接影响着治疗性克隆的临床应用;核移植胚胎干细胞分离培养效率的高低以及向重要功能细胞定向分化是治疗性克隆的前提;成体干细胞可用于一些重大疾病的治疗,但不能完全替代克隆性治疗;伦理问题也阻碍治疗性克隆的发展。核移植及治疗性克隆技术要想尽快更好地应用于临床和造福于人类,需要不断完善各技术环节和加强一些基础理论的研究。Abstract: Nuclear transfer and therapeutic cloning have widespread and attractive prospects in animal agriculture and biomedical applications. We reviewed that the quality of oocytes and nuclear reprogramming of somatic donor cells were the main reasons of the common abnormalities in cloned animals and the low efficiency of cloning and showed the problems and outlets in therapeutic cloning, such as some basic problems in nuclear transfer affected clinical applications of therapeutic cloning. Study on isolation and culture of nuclear transfer embryonic stem (ntES) cells and specific differentiation of ntES cells into important functional cells should be emphasized and could enhance the efficiency. Adult stem cells could help to cure some great diseases, but could not replace therapeutic cloning. Ethics also impeded the development of therapeutic cloning. It is necessary to improve many techniques and reinforce the research of some basic theories, then somatic nuclear transfer and therapeutic cloning may apply to agriculture reproduction and benefit to human life better.