近交系大鼠DNA指纹分析研究

目的建立DNA指纹技术对近交系大鼠遗传监测的方法.方法采用DNA指纹图法对国内已知的7个品系9个近交系大鼠群体进行了分析,并对相同DNA进行了多次DNA指纹图重复实验.结果(1)不同品系之间DNA指纹图差异较大,其平均图带数为16.360±2.178,共有带率为0.061±0.008,相似系数为0.062±0.008,相同DNA指纹图概率为3.691×10-23.(2)同一群体不同个体之间DNA指纹图带的相似系数和共有带率(除SHR(哈)和WKY(哈)小于0.7外),其他均在大于0.9.(3)不同地区同一SHR和同一WKY品系间DNA指纹图也存在不同,其相似系数和共有带率均小于0.6.(4)相同DNA不同次制作的DNA指纹图谱基本一致(P>0.05).结论证实了该方法在近交系大鼠遗传监测中的可行性.     

荧光素标记JH12.6探针进行的人DNA指纹图分析

采用荧光素标记和鲁米诺化学发光技术,建立了ＤＮＡ指纹图的分析方法。用该方法标记ＪＨ１２．６探针获得了清晰易读、分辨率高的人ＤＮＡ指纹图。经对云南省７８名无关个体进行ＤＮＡ指纹图分析,计算出无关个体的相关机率为７．４×１０（－１１）,平均等位基因频率为０．０９。比较同位素（３２）Ｐ标记方法表明,用荧光素标记ＪＨ１２．６探针进行人ＤＮＡ指纹图分析,具有简便、快速、安全、经济的特点,可在法医学鉴定及其它领域里推广应用。     

(GTG)5探针产生的DNA指纹图在近交系小鼠遗传检测中的应用

目的探讨用非放射性标记的寡聚核苷酸探针(GTG)5进行近交系小鼠的DNA指纹分析。方法用非放射性标记的寡聚核苷酸探针(GTG)5制作BALB/c、C57BL/6J、DBA/2、C3H近交系小鼠的DNA指纹图,对这四个品系的小鼠进行遗传检测,分析各品系内和品系间的遗传变异性。结果(GTG)5探针可产生具有良好多态性的DNA指纹图,平均图带数为8~12条。各品系内的DNA指纹图平均相似系数(-x)在0.96~1.00的范围内,具有相同指纹图的概率(P)均在3.1×10-1以上,极显著地高于品系间的相似系数(0.22~0.39)和相同指纹图的概率(P<1.07×10-4)。结论(GTG)5可用于制作近交系小鼠的DNA指纹图以对其进行遗传检测。     

动物的双亲判别与DNA指纹图谱

在亲缘识别和婚配选择等动物行为学研究中,需要知道动物之间的亲缘关系。通过分析以往的各种双亲判别方法,如蛋白电泳和血清学技术等,其中DNA指纹图谱法被认为是目前最好的。这种方法已在许多种动物(狗、猫、小家鼠、家燕、蓠雀、天鹅等)和人的研究中得到应用。DNA指纹图谱方法的基本原理是这样,两个动物的DNA 片断具有完全相同的碱基排序的情形从理论上讲其可能性极小,所以每个个体(除同卵双生子外)的DNA经提取、酶切、凝胶电泳、RNA或DNA探针杂交和放射性自显影后所形成的条带分布应该是有区别的、具有个体的特异性,这些条带就是DNA指纹图谱。动物个体DNA 指纹图谱中的每一条带,除了偶然发生的基因突变, 都可以从父母双方、或父方、或母方找到。据此,本文介绍了如何使用DNA指纹图谱进行包括父方和母方亲代判别的方法,如条带比较法和相似性系数法。     

血满草RAPD-PCR反应体系的建立与DNA指纹图谱研究

目的:获得稳定性、重复性好的RAPD-PCR反应体系,并构建血满草DNA指纹图谱和进行遗传多样性分析。方法:以血满草3个居群11个个体的幼叶为材料,CTAB法提取基因组DNA,从模板浓度、引物浓度、d NTPs浓度和Taq DNA聚合酶的用量,构建最佳的RAPD-PCR反应体系,通过扩增带型的差异构建其DNA指纹图谱,利用Popgen32、NTSYS2进行遗传多样性分析。结果:3个RAPD引物扩增血满草3个居群11个样品共获得27条可靠、清晰和重复性高的条带,其中17条是多态条带。引物SBSA5和SBSA11扩增条带组合可以构建11个样品的个体特异DNA指纹图谱。供试血满草居群间遗传距离在0.1493~0.2312之间;居群内的遗传多样性分别为0.1102、0.0153、0.2294。遗传距离和相似性聚类分析表明,样品间的遗传距离与居群的地理分布关系不明显。结论:RAPD分子标记在构建血满草DNA指纹图谱是可行的,由其构建的指纹图谱可以将供试个体相互区分鉴别出来。无论是居群间还是居群内,供试血满草的遗传多样性均较低,居群间的遗传分化较小,可能还在属于同一个大的居群。     

DNA指纹图技术分析微生物肥料菌种组成稳定性

目的 分析2种市售微生物肥料在不同生产批次中微生物菌种组成的稳定性。方法 利用ERIC-PCR基因组DNA指纹图技术和16S rDNA V3扩增一温度梯度凝胶电泳（PCR-TGGE）指纹图技术。结果 这2种微生物肥料在同一个生产批次不同包装之间的2种DNA指纹图谱相似性较高,分别在78%～95%和96%～100%,表明同一个批次内的菌种组成比较一致,但其在不同的生产批次之间菌种组成差异存在显著性,反映在2种DNA指纹图谱上,不同生产批次样品间ERIC-PCR指纹图相似性最低只有10%,PCR-TGGE指纹图相似性最低为46%。结论 通过ERIC-PCR和PCR-TGGE DNA指纹图技术可以对微生物肥料中菌种组成的稳定性进行快速、准确的分析,如何保持菌种组成在批次之间的稳定一致,是复合菌种微生物肥料质量控制中面临的难题。     

纵纹腹小鸮DNA指纹谱探针的筛选和初步应用

以人工合成的微卫星序列 (GTG) 5,(GT) 8,(CAC) 5和人源小卫星 33 1 5作引物 ,扩增纵纹腹小的基因组DNA ,产生多态性DNA片段 ,回收了 8个表现个体特异性的片段。当用小的基因组总DNA探针与它们杂交时 ,其中 2个表现阳性 ,说明PCR方法扩增出的高变异产物含有重复序列。用含重复序列的个体特异性PCR产物作探针 ,与无关个体小基因组DNA的HaeⅢ酶切产物进行DNA印迹 ,获得了变异性较高的DNA指纹图谱。且通过对京白鸡家系分析表明 ,用小基因组DNA的PCR产物分离制备的探针所获得的DNA指纹图带能够稳定的遗传。因此 ,高变异的PCR产物可以有效地用作DNA指纹探针。     

用DNA指纹图技术分析Wistar大鼠的遗传距离

采用JL-02多位点探针和Southern杂交对Wistar大鼠基因组进行了DNA指纹分析,并对国内最具有典型的6个地区9个Wistar大鼠群体内和群体间进行了DNA指纹分析比较。结果表明,DNA指纹图较好地反映了封闭群动物的遗传本质,具有良好的多态性。同一群体不同个体间Wistar大鼠遗传距离主要为0.2~0.6,将不同群体的Wistar大鼠DNA指纹图带进行分析表明,所有群体间的DNA指纹图的遗传距离在0.2~0.7。 Abstract:DNA fingerprinting of Wistar rat were studied with JL-02 Mulilocus probe and Southern hybridization,and comparing with different individuals of nine groups Wistar rat from six national classical area and different groups.It was indicated that DNA fingerprinting could reflect genetic material of outbred strain rat,and were more polymorphic.The genetic distances of Wistar rat were distributed for 0.2~0.6 among different individuals within same groups,and the genetic distances of Wistar rat were distributed for 0.2~0.7 among different groups．     

α-珠蛋白-3′HVR探针DNA指纹图法医应用的研究

本文用α-珠蛋白-3'HVR探针所建立的杂交方法,获得清晰可辩的DNA指纹图。就北京地区200名无关个体的DNA指纹图分析和统计结果,其相关机率为4.0×10~(-12),对6个家系的32名相关个体的分析,符合孟德尔定律,足以用作准确的个人识别和亲子关系鉴定,并巳用于检案,为侦破强奸、凶杀等案件提供了重要依据。     

幽门螺杆菌随机扩增多态性DNA指纹图谱分析

应用随机扩增多态性DNA指纹法(RandomamplifiedpolymorphicDNA,RAPD)对来自29例消化性溃疡和19例单纯性胃炎病人的幽门螺杆菌(Helicobacterpylori,Hp)菌株基因组DNA进行PCR反应,建立Hp的DNA指纹图谱,运用统计分析软件(Statisticanalysissoftware,SAS)对HpDNA指纹图的相似性以及与疾病的相关性进行分析。结果显示,这些菌株按HpDNA指纹图可分为两大类,两种来源的菌株在两大类中的比例有明显差异(P<0.05)。提示可能存在与疾病相关的特异基因型。     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

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     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.