关于DNA甲基化对肿瘤影响的研究进展

表观遗传是指DNA序列不发生变化但基因表达却发生了可遗传的改变[1]。表观遗传学研究染色质重塑、DNA甲基化、X染色体失活、非编码IKRNA调控4个方面,其中的任何一方面异常都能引起疾病甚至癌症。各研究表明DNA甲基化和组蛋白修饰异常在多种肿瘤的发生中起着重要作用。本文以胃癌形成原因为例对DNA甲基化在肿瘤行程中的重要作用进行概述。     

基于MSRF的黄海漂浮浒苔与定生浒苔的甲基化差异分析

应用甲基化敏感限制性指纹技术(MSRF),利用对DNA甲基化敏感与不敏感的限制性内切酶组合产生基因组的酶切多态性差异图谱.发现漂浮浒苔可能在BstUI位点发生了甲基化增强的现象,推测表观遗传水平上的改变可能推动了漂浮浒苔对黄海自由漂浮生活的快速适应.     

演绎承续魅力 开启制药新章——记复旦大学生物医学研究院表观遗传实验室蓝斐教授

科学理论研究成果唯有搬下高阁,走入寻常百姓家才能真正实现其价值,这在解民于疾苦的医学研究领域里体现得尤为明显。蓝斐最大的特点是在尚不为人所熟知的表观遗传学领域,开启了一部创新制药的新篇章。他不是医者,但有一颗医者仁心。什么是表观遗传学?或许很多人会有这样的疑问。确实,与广为人所知的遗传学相比,"表观"两字的加入顿时让本已让人难以参透的遗传学多了几重迷雾。表观遗传学是与遗传学相对应的概念。遗传学是     

表观遗传学与疾病的发生

表观遗传学是近年研究的热点,随着表观遗传学的研究,人类对表观遗传学的调控机制,如DNA甲基化、组蛋白修饰、非编码RNA与染色体重塑等有了深入了解,同时也证明了表观遗传学与人类疾病之间存在密切联系。     

表观遗传学学术研讨会暨双清论坛在烟台召开

为了研讨当今表观遗传学研究的现状和趋势,了解我国表观遗传研究的状况,探讨我国表观遗传学研究的发展,国家自然科学基金委员会于2007年10月在山东省烟台市召开表观遗传学学术研讨会暨“双清论坛”。     

组学时代的表观遗传学研究的机遇和挑战

表观遗传学(epigenetics)是诠释可遗传的基因表达记忆的建立和细胞代间传递的、而并非由DNA排序决定的机制的一门学科。从有着深刻内涵的生物学过程: 生殖, 发育, 老年化和重大疾病着手,解读这一位于基因型和表型之间乃至基因型和环境关联之间信息界面的组构和运营规律是今天生命科学研究的核心内容。以高信息量技术为依托, 以发现(discovery)而非假设(hypothesis)驱动的组学时代的研究模式已赋予传统表观遗传学研究以新的活力。美国已启动的1.9亿美元/5年的表观遗传组学NIH路标图计划和全球筹化中的正常与疾病表观遗传组学计划必将推动表观遗传信号、机制和生物学效应进程的诠释, 继而对生物医学和现代化农业的发展给予有力的推动,同时赋予小科学研究的组学化特征。可以预期,系统全面的表观遗传学研究会对个性化医学、干细胞技术为基础的再生医学、环境医学和优良性状、高产经济物种的培育等关键生物学问题提供解决方案。我们应充分发挥优势, 抓住表观遗传 (组)学中核心的生物学问题, 开展有原始创新并能对国计民生发生巨大影响的科学研究。     

DNA甲基化与肿瘤

最近的研究资料提示DNA序列的改变和Epigenetics(表遗传学或拟遗传学)的机制都参与了肿瘤的发生。DNA甲基化后核苷酸顺序未变,而基因表达受影响,异常甲基化是肿瘤发生的重要原因。笔者综合近年的有关文献对肿瘤细胞DNA甲基化形成的原因及机制作一综述。     

基化CpG结合蛋白2(MeCP2)基因的克隆和Western检测

DNA的甲基化作用作为一种常见的表观基因修饰方式广泛存在于生物体内,与DNA甲基化密切相关的蛋白--甲基化CpG结合蛋白(MeCPs)在DNA甲基化中起着非常显著的作用.通过浅谈DNA甲基化的作用及MeCP2的相关功能,并且构建了可表达MeCP2的载体,为进一步研究MeCP2在肿瘤和Rett综合症中的作用打下基础.     

“细胞编程和重编程的表观遗传机制”重大研究计划结题综述

国家自然科学基金委员会重大研究计划"细胞编程和重编程的表观遗传机制"历时8年于2017年完成结束评估。本文概述了该计划取得的研究进展,特别是在发现新的表观遗传调控因子和染色质重塑因子并揭示其生物学功能和作用机制,解析干细胞自我更新、体细胞重编程的调控机理及创建半克隆新方法,揭示表观遗传调控细胞分化转分化、个体发育及疾病发生发展的规律,以及从全基因组的层次上认识表观遗传网络形成和运行的机制等方面取得一系列突破性研究成果,产生了重要国际影响。文中展望了表观遗传学研究的发展态势,提出了未来关注的重点学术方向。     

又一种遗传型式

DNA的甲基化也许是一种主要的“后生遗传”机制。在发育过程中，基因活性模式(相对于基因本身而言)正是借助于这个机制由上一代细胞传递给下一代细胞的。     

Students' Reactions to the Introduction of Videoconferencing for Classroom Instruction

This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors.     

Cooler temperatures inductive to locust outbreaks

Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007.     

Exploring Multiplexity: Social Network Structures in a Computer-Supported Distance Learning Class

A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction.     

The Role of Intermediating Institutions in the Diffusion of Electronic Data Interchange (EDI): How Industry Associations Intervened in Denmark, Finland, and Hong Kong

Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies.     

Low doses of a red wine ingredient figh diabetes in mice

Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said.     

How Electronic Publishers are Protecting Against Piracy: Doubts About Technical Systems of Protection

The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means.     

Rough Justice: A Statistical Assessment of ICANN's Uniform Dispute Resolution Policy

Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP.     

Prevalence of soft neurological signs in Chinese people

Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.     

Molecular motor assembly of a biomimetic system

Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction.     

Monoculture Rubber Plantations Have Negative Ef ects on Controlling Splash Erosion

<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence