水产疫苗研究开发现状与趋势分析

水产疫苗不仅能够增强水产动物的免疫力,预防水产病害发生,还能减少各类药物的使用,降低生殖生产成本,解决各种药物残留带来的食品安全和环境污染等问题,使水产养殖业向绿色、可持续方向发展。因此,水产疫苗已成为水产动物病害防治领域的研究热点。综述了水产疫苗的发展历程、水产疫苗种类与接种方式,并介绍了水产疫苗关键技术发展现状与趋势。     

菌蜕系统作为新型渔用疫苗体系的研究进展

菌蜕系统作为一种新型疫苗体系,是通过对噬菌体PhiX174裂解基因E的精确表达调控建立的.细菌菌蜕兼顾了组合抗原免疫原性、佐剂效应、靶向性载体等作用,特别适合于黏膜免疫及口服免疫;由于缺乏内含物而更加安全;生产过程简单,适宜大规模生产.这些特性决定了细菌菌蜕是一种具有良好应用前景的候选疫苗及递送系统.近年来随着水产养殖业的发展,鱼类细菌性疾病大规模爆发并造成严重损失.鉴于化学药物和常规疫苗的种种缺陷,新型渔用疫苗的研究日渐受到人们重视.在阐述细菌菌蜕系统形成和调控机制的基础上,着重介绍菌蜕疫苗在几种鱼类细菌性病害防治中的研究进展,并对菌蜕系统作为新型渔用疫苗体系的可行性和优越性进行讨论,对其应用前景进行展望.相信随着研究的深入,渔用菌蜕疫苗将在水产养殖病害防治中发挥着越来越重要的作用.     

鱼类病原菌外膜蛋白及其免疫原性研究进展

细菌性疾病是水产养殖病害中最常见且危害甚为严重的一类疾病1。长期以来,一直用于鱼类细菌性疾病防治的西药类药物,由于会导致病原菌产生耐药性,在鱼体内产生药物残留危害人类健康等副作用而被限制使用2。因此,为了选择更加安全有效的防治方法,疫苗免疫逐步得到了人们的重视。       

致病性弧菌外膜蛋白及其免疫原性研究进展

弧菌为水产养殖环境中常见的条件致病菌,其暴发可导致养殖鱼虾贝类大量死亡。由于常用的化学药物防治方法存在耐药性、药物残留等问题使得弧菌病的防治面临新的挑战,因而如何获得安全有效的防治方法成为弧菌所致疾病研究的重点和难点。弧菌为革兰氏阴性菌,外膜是该类型菌细胞壁特有的结构,由蛋白、糖和脂质构成。其中外膜蛋白易为宿主免疫系统识别为异物,可以激发机体的体液免疫和细胞免疫,有可能作为弧菌疫苗的有效成分。对弧菌外膜蛋白免疫原性的研究进展作一综述,以期为弧菌病的防治在外膜蛋白水平上提供一种有效的解决途径。     

噬菌体在防控鱼类细菌性病害中的作用机制及其应用

鱼类细菌性病害对发展鱼类养殖业构成了严重的威胁,而抗生素的滥用和病原菌耐药性的出现对鱼类养殖产量、水产品质量和养殖环境造成了严重的影响。为了推动鱼类健康养殖产业的发展,亟待创新研究鱼类病害的绿色防控技术。噬菌体作为一种天然、无残留的细菌杀手,具有特异性强、裂解效率高等特点,利用噬菌体治疗鱼类细菌性病害将是一种重要的技术途径。本文综述了噬菌体的重要资源挖掘、鱼类细菌性病害防控中的作用机制及其应用前景,并提出了在鱼类健康养殖领域加快研究噬菌体治疗技术的措施,对鱼类的健康养殖具有重要意义。     

重要海水养殖动物病害发生和免疫防治的基础研究

随着捕捞资源的急剧衰减,水产养殖已成为国际社会为满足人类日益增长的蛋白质需求而普遍采纳的主要举措.我国是水产养殖大国,但病害发生严重制约养殖业健康可持续发展.近年来,病害导致的水产养殖业直接经济损失每年超过百亿元.此外,药物滥用导致水产品药物残留等食品安全问题,还造成了病原微生物耐药性增加及养殖环境恶化.开展病害发生和免疫防治基础研究,对支撑水产业健康持续发展,确保我国21世纪食物安全,提高国民健康素质,引领我国渔业经济发展和水产科学的创新都是非常重要和紧迫的.     

微生物方法降解刺参养殖池塘中氨态氮的研究进展

随着刺参养殖业的迅速发展,刺参池塘养殖暴露出诸多问题,如水体氨态氮含量高、病害严重、单位产量下降等.传统药物弊端较多,微生物方法成为降解水体中氨态氮含量和预防病害发生的新的有效途径.综合阐述了刺参池塘养殖过程中氨态氮对刺参的危害和微生物降解氨态氮的利弊,并介绍了水体中氨态氮高效降解菌株的筛选以及现有微生态制剂存在的问题,对微生物方法降解刺参养殖池塘氨态氮的前景进行了展望.     

对虾PjCaspase基因启动子的克隆及其特征的初步分析

对虾是最重要的海水养殖产品之一,但是自从20世纪90年代以来,一直受到病害的严重威胁,尤其是对虾白斑综合症病毒(White spot syndrome virus,WSSV),已成为危害对虾养殖的最主要病原[1]。但因对虾等海洋无脊椎动物的免疫系统不完善,无法用疫苗进行免疫防治[2],至今尚无有效的防治药物,因此滥用违禁药物现象普遍,严重影响对虾的品质。     

药用植物资源在水产动物疾病控制中的研究进展*

随着生活水平的不断提高,人们对水产品的需求量日益增加,水产养殖业得到飞速发展。然而,各种寄生虫、细菌和病毒诱发的疾病给水产养殖业造成了巨大的经济损失,严重制约了水产养殖业的快速稳定发展。作为传统的防治手段,抗生素等化学合成药物常用于水产养殖过程。大量化学合成药物的滥用诱发了药物残留、耐药菌等环境污染问题,危害人类健康。因此,具有多种有效活性成分的中草药因其天然、安全、副作用小等原因,成为探索新型防控水产病害暴发手段的研究对象。当前,中草药常被用于调节水产动物的免疫力、生长速度和预防疾病暴发等。同时,中草药还可用于改善养殖环境,降低环境因子对水产动物的胁迫。然而,目前的研究主要集中在从中草药中获取防控疾病暴发的复合有效成分,存在药效不稳定、活性成分不明确等问题,无法满足生产高效、廉价、稳定防治剂的需求。论述了当前中草药在防控水产动物疾病暴发中的应用及其作用机制,揭示了对中草药活性分子作用机制研究的不足,强调了中草药作为一种更环保、更有效的水产养殖疾病防控手段进行应用的潜力,对其抗病机制的深入研究尤为重要。     

重要水产养殖动物病原菌高效多价疫苗保护原的研究

以疫苗为核心的免疫防治是控治水产动物养殖业微生物病害的必由之路。鉴于水产养殖动物病原菌种类繁杂、血清型多样,同时从经济方面考虑也不可能对所有病原菌及其血清型逐一进行疫苗预防接种。因此,研制疫苗必须在思路和技术上进行创新。该文提出了以发展多价疫苗为思路的水产养殖动物细菌性疾病控制的新免疫预防措施,介绍了发现和鉴定多价疫苗候选功能靶位的研究思路和技术路线,展望了基于免疫层次抗原组学的新概念对系统深入研究天然高效多价保护原的良好前景。     

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.