利用转基因植物表达药用蛋白

随着药物生物技术和植物基因工程迅速发展 ,转基因植物被用作生物反应器生产具有医疗价值的多肽和蛋白质已成为生物医学研究的热点。研究表明转基因植物表达的蛋白质能够保持原有的结构和功能 ,这预示它将为药用蛋白的生产提供一条安全和廉价的新途径。主要概述了近年来国内外转基因植物生产诸如疫苗、抗体和其他药用蛋白或多肽等的研究进展 ,并着重探讨了存在的问题和解决策略。     

转基因植物生物反应器中存在的问题及解决途径

利用转基因植物作为生物反应器,可以大量生产重组药物蛋白质和工业化酶,但是表达量低、下游处理复杂、糖基化结构改变是植物反应器中经常遇到的困难,这些困难限制了转基因植物的商业化发展。针对这些问题,人们分别采用不同的生物技术策略加以解决。     

新型基因工程药物

本文主要介绍转基因植物基因工程生产的疫苗、转基因动物乳腺生物反应器生产的基因工程药物的基本生产方法以及应用研究进展,重点分析了这些新型基因工程药物的优点和存在的问题．概括了微生物发酵、动物细胞培养生产的基因工程药物的临床试验及投放市场的现状．     

抗虫转基因植物的研究进展及前景

虫害对农业生产的危害日益严重。目前对害虫的防治主要依赖于化学药物,但化学药物的副作用不容忽视。利用植物基因工程获得抗虫转基因植物是更具前景的途径。目前主要利用的抗虫基因是苏云金杆菌的δ－内毒素基因和植物来源的抗虫基因（如蛋白酶抑制剂基因、淀粉酶抑制剂基因、凝集素基因等）,各种抗虫基因在转基因应用中各有其优缺点,如苏云金杆菌δ－内毒素基因在植物中表达水平低。随着抗虫转基因植物在大田中的应用,昆虫的抗性或适应性问题也随之产生,这将是转基因植物发展道路上又一挑战。     

转基因植物基因工程疫苗

对转基因植物生产疫苗的方法进行了介绍,概括了转基因植物疫 的主要优点和存在的问题,总结了10年来转基因植物疫苗的研究进展,并对未来的发展方向进行了讨论。     

转基因植物疫苗研究策略

利用转基因植物作为生物反应器生产疫苗受到越来越多的关注。对转基因植物疫苗的研究、生产策略进行了介绍 ,重点对提高植物疫苗表达所采用的生物技术策略进行综述 ,探讨转基因植物疫苗的发展及面临的问题。     

转基因植物生产疫苗和药物的研发进展

与传统的生产方式相比,以转基因植物作为生物反应器生产药用蛋白和疫苗,被认为是成本低廉、安全便捷的技术途径。目前,若干以转基因植物生产的药用蛋白已通过行政审批准予上市,一批转基因植物表达的人用或畜禽用疫苗也进入临床试验。综述了转基因植物生产疫苗和药用蛋白的研发进展与代表性案例,讨论了目前面临的问题与挑战,展望了未来技术发展方向。     

转基因植物疫苗的研究进展

近些年,随着遗传技术和植物基因工程的发展进步,疫苗（亚单位疫苗、活载体疫苗和核酸疫苗等）的研究迅速发展起来。尤其是利用转基因植物技术生产植物疫苗的研究受到了广泛的关注,在转基因植物（蔬菜、水果、农作物）的可食用部位表达抗原生产人或动物治疗用重组蛋白和疫苗的技术为可食性疫苗的研制开辟了新途径,展现了诱人的开发前景。植物来源的疫苗具有很多优势,如生产成本低、易于保存、免疫接种方便、甚至不需提取纯化等处理而直接食用。目前已有很多转基因植物疫苗产品投入开发和生产。文章综述了近几年转基因植物疫苗在表达系统、生产、生物安全／管理、公众健康等方面的研究进展,对转基因植物疫苗存在的问题进行了分析,并对其研究前景提出了展望。     

转基因植物作为生物反应器在疫苗生产中的应用

对转基因植物生产口服疫苗的发展、优点与作用机理、方法原理进行介绍,概述当前各种转基因植物疫苗的研究现状,指出了转基因植物疫苗研究面临的问题与前景 。     

转基因植物生产重组药物蛋白的研究进展

转基因植物作为一种新型生物反应器,可以安全、经济、有效的生产各种重组蛋白,以此作为大规模的重组药物生产平台备受瞩目。但是表达量低、下游处理复杂、糖基化结构改变是植物反应器中经常遇到的困难,这些困难限制了植物表达重组药物蛋白的商业化发展。针对这些问题,人们分别采用不同的生物技术策略加以解决,对此做一简要综述。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.