食源性致病菌多重分子生物学检测技术研究进展

快速、可靠的食源性致病菌高通量检测方法对于确保食品安全具有重要意义,近年基于DNA水平的多重分子生物学检测技术迅速发展,针对各种不同的食源性致病菌建立了多种多重分子检测技术,包括多重PCR、多重实时荧光PCR以及基因芯片等。对这些多重分子检测技术的最新研究进展作一综述,并且建议在今后该技术的研究中,仍需要在食品中多种致病菌同时选择性增菌培养、亚致死损伤修复以及检测内标的构建等方面取得突破,从而能够更好地实现食源性致病菌的高通量检测。     

食源性致病菌高通量检测方法及应用

食源性致病菌的体外培养一直是病原体诊断的金标准,但按照目前的培养技术仅有1％的细菌可以培养.目前用于病原微生物鉴定的高通量检测技术主要有:多重PCR技术、实时荧光定量PCR技术、核酸等温扩增技术、焦磷酸测序技术和芯片技术等,本文介绍了这些高通量检测技术及其在食品病原微生物检测方面的应用情况.     

滨州市餐饮服务食品食源性致病菌污染状况

目的：了解滨州市餐饮服务食品中食源性致病菌污染状况,为食源性疾病的防控提供科学依据。方法：按照相关国标和标准检测方法对2014—2017年餐饮服务食品中主要食源性致病菌进行监测。共采集滨州市10大类食品共计328份,进行4种食源性致病菌的分离鉴定。结果：食源性致病菌检测中,328份样品中共检出致病菌45份,总检出率为13.72%。单核细胞增生李斯特氏菌合格率为100.00%,蜡样芽孢杆菌检出率较高。食源性致病菌高检出率样品集中在街头摊点及第三季度。结论：滨州市餐饮服务食品中食源性致病菌存在一定程度污染,应加强餐饮服务环节中食源性致病菌的防控措施,防止食源性疾病的发生。     

质谱法检测食源性致病菌技术研究进展

食源性致病菌存在广泛,能够引起人类的疾病甚至死亡,研究发现超过一半的食品安全问题来源于食源性致病菌的污染。如何快速有效地检测出食源性致病菌是预防和控制食品安全问题的关键环节。系统地介绍了检测食源性致病菌的方法,包括传统培养法、代谢学法、分子生物学法、免疫学方法等传统方法以及新兴的质谱法。质谱法有检测效率高、操作简便、灵敏度高等优点,着重对质谱法的原理、应用以及未来的发展趋势进行了阐述,以期为该技术的研究开发和推广应用提供参考。     

代谢组学研究技术及其应用

介绍代谢组学的研究技术,主要包括核磁共振技术,色谱-质谱联用技术,同时介绍常用的数据处理方法和数据库.对目前代谢组学在医药领域、生物研究领域、资源环境,以及农业和食品领域的应用情况进行综述.     

食源性致病菌检测技术的发展及研究现状

食源性疾病对人类健康产生越来越大的威胁,且因为抗菌类药物的广泛使用,食源性致病菌出现多重耐药现象。作为预防与控制食源性致病菌的关键环节,食源性致病菌快速检测技术的开发尤为重要。传统检测技术包括微生物培养法、免疫学检测技术和分子检测技术,存在周期长、对检测人员和检测环境要求高等不足,如何将不同检测技术的优点集于一体而规避相应的缺点是突破方向。随着生物科技的发展,新型检测技术逐渐兴起,如基于光学、电化学的生物传感技术或多种技术结合的新应用等。本文综述了常见食源性致病菌的生理特性及相应感染疾病,讨论了传统检测方法优缺点,并详细介绍了新型生物传感器检测技术的发展及现状,以期为开发更加便捷、准确、灵敏的食源性致病菌现场检测技术提供参考。     

食源性致病菌检测免疫传感器研究进展

食源性致病菌是造成食品安全事件的主要原因之一,因此其检测方法已成为人们研究的热点.食源性致病菌的检测方法主要有病原体培养法、免疫学方法、核酸检测和生物传感器等.其中,免疫传感器基于抗原抗体特异性结合,整合光学、电化学等多学科交叉技术,具有特异性强、检测速度快等特点.本文对比食源性致病菌传统检测方法,综述了近年来免疫传感...     

PCR技术检测食源性致病菌的研究进展

食源性致病菌的检测技术是食源性疾病预防与控制的关键环节。PCR是近年来广泛应用于食源性致病菌快速检测的方法之一。在食源性致病菌中,用于PCR检测的靶基因包括各种毒力基因、酶基因及特异性鉴别基因。这些靶基因的发现推动了食源性致病菌PCR快速检测的发展。     

微生物代谢组学的前处理及分析技术

微生物代谢组学主要研究细胞生长或生长周期某一时刻细胞内外所有低分子量代谢物。分析技术的不断发展促进了微生物代谢组学研究的进展。本文结合微生物样品前处理方法, 综述了目前研究中所采用的各种分析技术的特点与应用, 并展望微生物代谢组学研究中分析技术的发展趋势。     

基于高分辨质谱的非靶向代谢组学在食品造假鉴定中的研究进展

食品造假属于以经济利益为驱动的食品欺诈(Economically motivated adulteration,EMA),是目前影响及破坏食品安全秩序的重要因素之一。而随着人们生活水平的迅速提高,对食品品质提出了更高的要求,当下食品造假现象是公众极为关注的问题。以往,针对已知的目标物质进行定量检测的靶向代谢组学技术在食品检测中广泛应用,代谢组学技术已经成为食品科学研究中不可或缺的工具。近年来,针对食品造假现象,代谢组学的另一个分支,基于高分辨质谱(High-resolution mass spectrometry,HRMS)的非靶向代谢组学(Non-targeted metabolomics,NTM)开始运用到食品造假的鉴定中,并已取得快速的发展。对基于HRMS的非靶向代谢组学的食品造假鉴定工作流程进行了介绍,对其数据处理方式进行了概括,并就其在食品物种(品种)、产地和品质等造假鉴定相关应用分别进行了总结,最后还对基于高分辨质谱的非靶向代谢组学应用于食品检测中优点和缺点进行了概括,并对其在其他研究方向进行了展望,旨在对食品检测中代谢组学的最新研究进展进行总结和归纳。     

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.