BioLumix微生物荧光光电检测系统在化妆品中的应用评估

本研究将用于化妆品中Bio Lumix微生物荧光光电检测系统与《化妆品安全技术规范2015》微生物检测法进行了比较。结果显示两种方法结果基本一致,对于《化妆品安全技术规范2015》微生物检测法检测化妆品,出具可靠的检测报告需要5 d,而Bio Lumix系统快速检测化妆品细菌项目和霉菌、酵母项目可在16 h和35 h内分别发出预警,并可控制在48 h内完整地输出检测报告。Bio Lumix微生物荧光光电检测系统具有检测时间短、检测效率高、操作简单等优点。     

toxR基因作为荧光定量PCR靶基因设计TaqMan探针快速检测副溶血弧菌

以toxR基因为靶基因,通过优化反应条件建立了快速检测副溶血弧茵的TaqMan实时荧光PCR方法.特异性试验表明,该方法能选择性检测副溶血弧茵,而与金黄色葡萄球菌、沙门氏菌、单增李斯特杆菌等多种常见的食源性病原茵没有交叉反应:灵敏度试验表明,该方法最少可检测到25个拷贝的toxR基因重组质粒,对纯培养物和模拟食品样品直接检测的灵敏度分别为21 cfu/mL和210 cfu/g;重复性试验表明,同一样品于试验内及试验间的变异系数分别为0.9%和1.3%:所制作的标准曲线在2.5 × 101～2.5 × 106拷贝数之间有较好的线性关系,能对副溶血孤菌进行准确的定量分析.结果表明,本研究所建立的副溶血弧菌实时荧光PCR检测方法具有特异性好,灵敏度高、重复性好的特点,能进行定量检测,而且检测时间从核酸抽提到出实验结果仅需要3 h.是快速检测副溶血弧菌的有效手段.     

两种小鼠卵母细胞的核成熟检验方法比较

将生发泡(GV)期小鼠卵母细胞置于M2培养液中培养,分别在培养0 h、4 h、8 h和12 h收集卵母细胞,采用SYTO染色和免疫荧光标记方法进行小鼠卵母细胞的核成熟检验,并将结果进行比较.可以发现:SYTO染色和免疫荧光标记方法都可用于小鼠卵母细胞的核成熟检验,二者的结果没有显著性差异,但是,SYTO染色法更为快速、简便、廉价,可用于活体染色,适合于大规模检测,可应用于哺乳动物卵母细胞的核成熟检验.     

用YO-PRO-1和PI联合染色定量检测细胞凋亡

经不同浓度staurosporine处理诱导凋亡的G7细胞样品,分别用YO-PRO-1/PI和AV/PI进行荧光染色,借助流式细胞仪检测凋亡情况,将两种检测方法得到的结果进行统计学分析显示,二者有显著的相关性(r=0.9659,P<0.01),且没有显著性差异(P<0.05);另外,上述凋亡细胞样品经YO-PRO-1/PI染色后在荧光显微镜下计数凋亡细胞比例的结果与AV/PI流式细胞仪的检测结果也有显著的相关性(r=0.9903,P<0.01),且没有显著性差异(P<0.05)。以上这些结果表明,用YO-PRO-1/PI对细胞进行染色、借助流式细胞仪和荧光显微镜均能准确地检测细胞凋亡,可替代AV/PI流式细胞仪方法用于细胞凋亡的检测。     

饮用水微生物的安全快速检测

【目的】为了更好地分析饮用水中的微生物含量。【方法】利用流式细胞术(Flowcytometry,FCM)、ATP测定方法检测瓶装无气饮用水中的微生物数量、可同化有机碳(Assimilable organic carbon,AOC)含量以及微生物活性,并将检测结果与传统的饮用水微生物检测技术相对照。【结果】FCM方法可快速区分水样中的活性细菌和非活性细菌,AOC含量反映了水样中微生物再生能力;而ATP检测方法也能比异养细菌平板计数法(Heterotrophic plate count,HPC)更好地反映瓶装无气饮用水中的实际微生物含量。【结论】FCM、ATP测定方法要明显优于依赖于培养的传统方法。     

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.     

流感快检法与病毒分离法检测结果的比较

实验中用流感快检法和病毒分离法同时对61份标本进行检测,并进行了比较,快检法的阳性预测值为100%,阴性预测值为40.9%,两种方法的符合率为57.3%。结果表明,快检方法可以作为快速的辅助手段。     

细胞计数板在荧光显微镜观察B细胞吞噬现象的应用探讨

目的:基于细胞计数板建立一种简单、快速使用免疫荧光显微镜观察B淋巴细胞吞噬卡介苗(BCG)现象的新方法,对即将进行流式细胞检测的样品进行质控,提高流式细胞术检测吞噬率的稳定性,同时为流式细胞仪检测吞噬率提供镜下依据。方法:B细胞与FITC标记的BCG共培养24 h后,PE anti-human CD19抗体直接标记细胞膜,应用细胞计数板在荧光显微镜下观察B细胞吞噬现象,流式细胞仪检测吞噬率。结果:应用细胞计数板在荧光镜下可观察到B细胞与BCG的荧光标记及B细胞与BCG共标记现象,证实B细胞可吞噬BCG,流式细胞仪检测结果显示吞噬率为13.9%。结论:应用细胞计数板在荧光镜下可观察B细胞吞噬现象,且操作简便快速,能对流式细胞检测的样品进行质控,并提供镜下依据。     

绿色荧光蛋白标记的嗜水气单胞菌在温暖水体的存活及稳定性

用绿色荧光蛋白基因(GFP)标记嗜水气单胞菌4332株(Ah4332GFP),检测其在温暖水体中的存活及稳定性.在灭菌自然塘水中,Ah4332GFP存活47d之久,该菌浓度随时间而变化,呈现两个峰值;在非灭菌自然塘水中,Ah4332GFP存活18d,该菌浓度均随时间延长呈下降趋势.表明Ah4332GFP和天然细菌之间的相互作用影响其稳定性.用M9培养基检测Ah4332GFP质粒的稳定性,结果显示在传代培养40、70代后,质粒稳定率分别保持在473%和205%.可见pGFP是一种相对稳定的质粒,Ah4332GFP可用于微生物生态的研究.       

快速评价肠道微生物的qPCR方法的建立

【背景】近些年,16S rRNA基因测序与宏基因组分析常用于肠道微生物病原体检测。【目的】为了使检测不受限于高成本与耗时长的问题,基于荧光探针的实时荧光定量PCR(real-time fluorescence quantitative PCR, qPCR),建立一种评估人类肠道微生物群组成的平台用于检测肠道微生物丰度。【方法】从公共数据库筛选10种肠道中普遍存在的微生物分类群,使用20个粪便样本验证为10种靶标所设计的特异性引物与探针,最后通过比较qPCR方法和16SrRNA基因测序技术的检测结果来评估该平台的有效性。【结果】10对引物及其探针对靶标分类群具有特异性并且在HITdb数据库中靶向菌种的覆盖率超过70%;样本检测结果的变异系数(coefficient of variation,CV)小于10%,证明了该方法具有很高的稳定性;qPCR方法检测样本中物种的相对丰度与16S rRNA基因序列生物信息学分析结果大部分具有显著相关性(P<0.05)。【结论】本研究根据HITdb数据库设计的靶向微生物群的引物和探针检测到的粪便样本中微生物的相对丰度结果与16S rRNA基因测序结...     

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.