伤寒Vi多糖菌苗预防接种后三年抗体效价的持久性观察

<正> 在尼泊尔和南非德兰士瓦东部,采用随机抽样、双盲法并设对照区的试验,最近报告了纯化Vi多糖菌苗预防伤寒的效果。推测由接种菌苗而诱导的血清Vi抗体,其保护力至少可持续1～1 1/2年。 本文报告的是在马里兰、图尔斯大学和智利空军新兵的志愿者中,接种Vi菌苗刺激Vi抗体有效增长情况的研究,并对马里兰大学已接种学生随访36     

Vi抗原的分子生物学基础及应用

<正>1934年Felix等发现伤寒沙门氏菌的一种表面抗原,命名为Vi(Virulence)抗原。以后,人们在丙型副伤寒沙门氏菌、弗氏枸橼酸杆菌以及少数都柏林沙门氏菌中也发现有Vi抗原存在。历史上围绕着Vi抗原究竟是不是保护性抗原的争论,使人们对Vi抗原的认识不断深入,八十年代以来,受其他细菌多糖菌苗研制成功的启示,采用温和方法制备Vi多糖取得成功,对Vi多糖的保护力进行重新评价,人们对Vi抗原的研究进入一个新阶段。现将有关Vi抗原分子生物学的资料综述如下。     

伤寒Vi多糖菌苗多糖含量及分子大小测定试验

伤寒Ｖｉ多糖菌苗是我国新近研制成功的一种多糖菌苗。为了严格控制该制品的质量,经反复试验,建立了多糖含量和分子大小的测定方法。本文报导了（１）用火箭电泳法测定伤寒Ｖｉ多糖菌苗多糖含量。经对不同实验条件进行比较,选择出较为理想的条件。用该法测定８批样品。结果均符合规程要求。对其中５批样品进行６次重复试验表明,该法的重复性好,操作简单,是测定多糖含量较为理想的方法。（２）用琼脂糖柱层析法对２８批伤寒Ｖｉ多糖菌苗的分子大小进行测定。对用该法所得柱层析收集液分别用Ｈｅｓｔｒｉｎ法和２０６ｎｍ扫描法测定其多糖回收率,对测定结果进行比较。结果表明,两种方法的测定结果无显著性差异（Ｐ＞０．０１）,而且重复性均好。可根据实验室条件选择测定方法。     

由霍乱毒素或其B亚单位与高分子量或低分子量的Vi组成的Vi多糖—蛋白接合物的免疫原性比较

<正>伤寒沙门氏菌引起的伤寒在发展中国家最为常见而且病情严重。接种伤寒沙门氏Vi荚膜多糖预防伤寒已在两个控制伤寒的随机双盲研究中得到证实。在5—44岁的儿童和成人中一次注射Vi,可提供大约70%的抗伤寒保护作用。在尼泊尔和南非德兰土瓦东部大约有75%的接种者Vi抗体效价升高4倍以上,Vi抗体的升高与Vi菌苗的有效率相似。 Vi是半乳糖醛酸(1→,)的线形同种聚合体,有与其它荚膜多糖特有的相同特性,即在动物和人类中重复注射并不引起加强应答。 接种Vi刺激产生的保护性免疫成份是血清抗体。两种试验结果证明,Vi抗体的临界水平可提供对伤寒的免疫保护作用。为了增强免疫原性,从而     

伤寒Vi-rEPA结合疫苗在小鼠中的免疫原性研究

以伤寒Vi多糖疫苗及结合物含量分别为20％、40％、60％的伤寒Vi-rEPA结合疫苗经皮下免疫小鼠后眼眶采血分离血清,用ELISA法测血清抗体浓度。血清抗体分析表明,伤寒Vi多糖疫苗和伤寒Vi-rEPA结合疫苗均有良好的免疫原性,但伤寒Vi-rEPA结合疫苗的免疫原性优于伤寒Vi多糖疫苗;伤寒Vi多糖疫苗无加强免疫应答效应,而伤寒Vi-rEPA结合疫苗有加强免疫应答效应;不同高分子结合物含量的伤寒Vi-rEPA结合疫苗免疫小鼠,其结合物含量为40％、60％的伤寒Vi-rEPA结合疫苗比结合物含量为20％的结合疫苗具有更好的免疫原性,而前二者的免疫原性无显著性差异。     

伤寒Vi多糖蛋白结合疫苗原液稳定性研究

目的评价伤寒Vi多糖蛋白结合疫苗原液的稳定性,为该疫苗原液的制备、储存提供有力的数据支持。方法选取3批伤寒Vi多糖蛋白结合疫苗原液分别放置于(37±2)℃、(25±2)℃和2~8℃温度下,根据稳定性研究方案定期取样,对其主要评价指标(多糖含量、结合物含量、相对分子质量、鉴别试验)进行检测,评估疫苗原液的稳定性。结果伤寒Vi多糖蛋白结合疫苗原液于2~8℃放置22个月,(25±2)℃放置52 w,(37±2)℃放置24 w时,各项主要评价指标均符合其质量标准的要求。结论伤寒Vi多糖蛋白结合疫苗原液稳定性良好,在2~8℃可稳定存放22个月。     

火箭电泳法测定伤寒Vi多糖菌苗多糖含量

伤寒沙门氏菌Ｖｉ抗原系ａ─１,４─Ｎ─乙酰─半乳糖醛酸高度聚合体,其Ｃ２和Ｃ３位分别被Ｎ─乙酰基和０─乙酰基取代,它不能用分光光度法测定其含量,实验表明火箭电泳的火箭峰高与其样品中多糖含量的对数成直线相关关系,作者采用火箭电泳方法对全国六个生物制品研究所的１８批伤寒Ｖｉ多糖菌苗中Ｖｉ多糖含量进行了测定,结果表明多数制品符合规程要求,但部分制品多糖含量偏高,值得引起注意,各所三批制品差别不大,表明各所的生产工艺相对稳定,利用火箭电泳测定伤寒Ｖｉ多糖,操作简单,用时较短,所需样品极少,是目前较为合适的测定伤寒Ｖｉ多糖菌苗多糖含量的方法。     

伤寒Vi多糖菌苗接种反应观察

本文报告了对我国首次成功的伤寒Ｖｉ多糖菌苗进行人体接种反应观察结果,接种对象为２０至５４岁无伤寒病史,近年无伤寒菌苗接种史的健康人,共６０名,以完全随机的方法分为两组,实验组注射３０μｇＶｉ多糖菌苗,对照组注射Ｖｉ多糖菌苗的稀释液。其结果３０名Ｖｉ多糖菌苗接种者注射后体温无中重反应发生,局部红肿仅有１例中反应。注射后对血压、心律没有影响。红细胞计数,白细胞计数均在正常范围,与接种前相比,无显著差异     

伤寒沙门氏菌口服活菌苗Ty21a Vi抗原阳性突变株的组建及特性

<正>伤寒至今仍然是发展中国家的主要卫生问题,尤其在学令儿童中的发病率很高,据估计,全世界每年伤寒病例超过3000万,死亡病例约50万。灭活全菌体菌苗大约已经使用75年,尽管几个现场结果表明该菌苗有效,但因其产生不良反应的频率较高使之作为一种公共卫生措施使用而受到限制。 Germanier和Frer叙述了称之为Ty21a的伤寒沙门氏突变株,它缺乏UDP-葡萄糖-4表异构酶,当口服免疫人群时,Ty21a株显示出良好的可耐受性,该菌苗现场效果表明对人群提供了良好的保护水平(67～95%),口服肠溶衣制剂3次剂量投服后至少可提供为期4年的保护作用。 近年已对纯化Vi抗原的效力进行了两个现场考核。Vi抗原是一种α-1、4-2-脱氧-2-N-乙基半乳糖胺糖醛酸的同聚物,这种酸性多糖荚膜在伤寒病人的临床分离物中即使不是全部世是大部分的分离物中表达出来。通常Vi是一种毒力因     

国产与法国Merieux产伤寒Vi多糖菌苗人体接种反应及血清抗体应答比较

作者对国产伤寒Ｖｉ多糖菌苗和法国Ｍｅｒｉｅｕｘ产伤寒Ｖｉ多糖菌苗人体接种反应及血清抗体应答情况进行比较,接种后６～８小时法国菌苗的体温反应同国产菌苗相比有显著性差异（ｘ２＝５．３４７,０．２５＞Ｐ＞０．０１）,２４小时后反应消失,免后一月国产菌苗和法国菌苗Ｖｉ抗体四倍增长率分别为９１．８０％和８９．６％（ｘ２＝０．１６４,Ｐ＞０．０５）,ＧＭＴ分别为３６．９４和３５．４９（ｔ＝０．６５３,Ｐ＞０．０５）,二者均无显著性差异。     

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.