Hemadsorption-negative plaque test: new assay for rubella virus revealing a unique interference

A simple and rapid plaque procedure has been developed for detecting and accurately assaying rubella virus in a noncytopathic virus-cell relationship. Plaque-formation is based on the development, in individual cells infected with rubella virus, of a unique type of intrinsic interference to infection with Newcastle disease virus. Rubella virus-infected cells challenged with Newcastle disease virus and tested for hemadsorption 15 hours later stand out as hemadsorption-negative areas. Individual living cells infected with rubella virus can be resolved under conditions allowing standard cloning procedures. In principle, the hemadsorption-negative plaque test can be used to search for a new class of noncytopathic, non-hemadsorbing viruses-those that induce an intrinsic interference to infection by any hemadsorbing virus.     

Rubella virus: growth and cytopathic effect in primary cultures of cells of rabbit embryos

Primary cultures of rabbit (New Zealand white) embryo cells support growth of rubella virus. Distinct cytopathic changes are discernible within 6 to 8 days after inoculation. This cell system has been successful for the recovery of rubella virus from clinical materials and the demonstration of neutralizing antibody in patient serum.     

北京地区8种斑螟Wolbachia的感染检测及其wsp基因序列分析

采用PCR扩增法,对北京地区8种斑螟亚科昆虫：圆斑栉角斑螟、红云翅斑螟、曲小锯齿斑螟、叉斑螟、亮雕斑螟、富泽云斑螟、微红梢斑螟和牙梢斑螟进行了Wolbachia的wsp基因分子检测;结果发现,在富泽云斑螟、微红梢斑螟和牙梢斑螟体内存在Wolbachia感染,所得的wsp基因序列分别为590,600和613 bp。对序列进行系统发育分析,结果发现富泽云斑螟体内感染的Wolbachia属于B大组的Btab2组类群,而微红梢斑螟和牙梢斑螟体内感染的Wolbachia属于A大组。     

单波长太阳能灯诱杀微红梢斑螟1）

为探索无公害防治微红梢斑螟（ Dioryctria rbu ell a）的方法,采用320～585 nm的单波长太阳能灯开展了林间诱杀研究,筛选了诱杀微红梢斑螟的最佳波长、最适时间以及诱杀容器的颜色和置放高度,测定了其对非靶标昆虫的诱杀作用,比较了不同时段诱杀微红梢斑螟的数量和比例。结果表明：380 nm太阳能灯诱杀微红梢斑螟的总量与368 nm的诱杀量差别不大,却显著大于其他波长灯的诱杀量;以21：00—23：00时段诱杀数量最多;蓝色容器的诱杀量最大;将盛水容器放在距地面1．2 m高度比放在地面对微红梢斑螟有更好的诱杀效果;380 nm灯对其他鳞翅目昆虫、鞘翅目和膜翅目昆虫的诱杀量与对照灯的诱杀量相比无显著差异。因此,波长为380 nm的太阳能灯可作为诱杀微红梢斑螟的最佳灯具。     

微红梢斑螟的研究进展

微红梢斑螟(Dioryctria rubella Hampson),是我国主要的松梢害虫之一,对松树的正常生长及种子园生产造成严重障碍,至今仍无有效的防治方法.文章对微红梢斑螟的生态学特性以及防控技术的研究进展进行了综述,并对其研究方向进行了展望.     

微红梢斑螟研究进展

从微红梢斑螟生物生态学特性、监测预报技术和防治技术等方面,综述了我国微红梢斑螟的研究进展,并提出了今后的研究方向,以推动微红桃斑螟的研究。     

6种灌木耐水淹能力分析

以小叶蚊母、滨柃、水杨梅、龟甲冬青、罗城石楠、花叶杞柳6种灌木为研究对象,在人工控制的水淹条件下,观察其叶片水淹胁迫后的症状,分析其耐水淹能力,结果表明:水淹30 d后,小叶蚊母、水杨梅和花叶杞柳植株少量叶片出现水渍斑,排除多余水分并经过常规养护30 d后,植物生长恢复正常;而滨柃、龟甲冬青和罗城石楠水淹30 d后全部死亡。     

RUBELLA VIRUS: NEUTRALIZING ANTIBODY IN COMMERCIAL GAMMA GLOBULIN

In 19 lots of standard commercial gamma globulin from humans, the titers of antibody neutralizing rubella virus varied from, 256 to 2048. The titers could not be correlated with geographic location of the donors, method of extraction, or tissue source. Samples of gamma globulin from rubella convalescents had titers of 4096. These titers were approximately 20 times higher than those in serum specimens from patients ill with natural or experimental infection. Serum antibody appears to persist for a number of years at nearly the original titers.     

思茅松林的树木多样性与主要害虫发生的关系

 对思茅松Pinus kesiya var. langbianensis人工林的不同混交配置模式的树木多样性及其与思茅松主要害虫的发生程度之间的关系进行了连续2 a的研究（2009年和2010年）。思茅松与红木荷Schima wallichii,西南桦Betula alnoides或高阿丁枫Altingia chinensis的混交林以及栽松留阔思茅松人工林的多样性指数（Shannon指数）显著高于思茅松纯林,但林地的均匀度指数（Pielou指数）并不和多样性指数的变化一致。思茅松主要害虫思茅松毛虫Dendrolimus kikuchii,微红梢斑螟Dioryctria rubella,松实小卷蛾Retinia crstata的危害情况随林地树木多样性指数的增加而降低。在思茅区清水河乔林层中,思茅松毛虫［y = －29.929x + 70.61,R² = 0.966 7（2010年）;y = －14.578x + 34.213,R² = 0.974 9 （2009年）］,微红梢斑螟［y = －8.873x + 20.627,R² = 0.994 6（2009年）;y = －8.653x + 20.215,R² = 0.935 1 （2010年）］的受害率与乔木层的Shannon指数呈现更好的线性关系,而松实小卷蛾的受害率则与灌木层的Shannon指数呈较好线性关系［y = －5.672 7x + 14.964,R² = 0.835 8（2009年）;y = －4.476x + 12.27,R² = 0.838 1（2010年）。在景谷文朗,思茅松毛虫［y = －55.454x + 135.16,R² = 0.954 1（2009年）和微红梢斑螟［y = －23.895x + 57.907,R² = 0.983 1（2009年）］的受害率与乔木层的Shannon指数同样呈现较好的线性关系。图5表3参8     

辽宁兴城油松种子园球果害虫的研究

1984～1988年在辽宁省兴城油松种子园对直接危害油松球果的害虫进行了调查,发现有松果梢斑螟、微红梢斑螟、松实小卷蛾及金绿宽盾蝽,对这4种害虫的生活史、发生历期和生物学特性作了研究。     

青花菜病程相关蛋白基因 BoPR2 的克隆与表达

病程相关蛋白基因以家族形式存在于植物中,在抗病反应中起着重要作用。以青花菜为试材,利用PCR法克隆到1个PR2基因,定名为BoPR2。测序结果表明,BoPR2基因组全长1188bp,具1个内含子,编码区全长1092bp,编码351个氨基酸;序列比对和系统发育分析结果显示,BoPR2与野甘蓝、甘蓝型油菜和白菜PR2的相似度最高,在发育树上聚为一组,与亚麻荠、荠菜的相似度最低,亲缘关系最远;实时定量PCR结果表明,BoPR2的表达受芸薹根肿菌诱导,在10d时的相对表达量最大,约为对照的6倍;但BoPR2的表达不受核盘菌的诱导。BoPR2基因的克隆与表达分析,为青花菜抗病机理研究及开展分子育种奠定了基础。     

思茅松害虫研究

记载思茅松害虫5目11科28属37种,其中半翅目2科2属2种,同翅目2科2属3种,鳞翅目3科5属6种,鞘翅目3科15属21种,膜翅目1科4属5种;以鞘翅目种类最丰富,鳞翅目次之,膜翅目第三;思茅松害虫以枝干害虫种类最丰富,针叶害虫次之,种实害虫第三;松墨天牛、纵坑切梢小蠹、马尾松角胫象是主要枝干害虫,云南松毛虫、思茅松毛虫、南华松叶蜂、广西新松叶蜂为主要针叶害虫,微红梢斑螟是主要球果害虫.     

十字花科植物PIN3基因调控元件及表达分析

为探明十字花科不同物种PIN3基因的表达调控差异,从拟南芥(Arabidopsis thaliala)、红花荠菜(Capsella rubella)、白菜(Brassica rapa)、油菜(Brassica napus)和甘蓝(Brassica oleracea)等17个已完成基因组测序的十字花科物种基因组数据库中鉴定出18个PIN3同源基因。对这18个同源基因编码序列上游1 500bp启动子区域顺式作用元件进行预测及比对分析,结果发现,光响应、多种激素响应及胁迫响应等相关元件呈现出较大差异,其中生长素以及向地性响应相关元件具有较高的保守性。克隆普通荠菜PIN3同源基因(CbPIN3)并构建普通荠菜PIN3基因启动子的GUS报告系统CbPIN3pro::GUS转化拟南芥。与拟南芥基因表达数据库比较,荠菜启动子表达与拟南芥PIN3具有基本一致的组织表达模式,但也存在一定的组织差异,说明植株形态建成中生长素极性转运调控的差异。拟南芥和荠菜PIN3的表达差异是十字花科物种适应性进化模式的缩影。     

Peripheral clonal elimination of functional T cells

A major mechanism for generating tolerance in developing T cells is the intrathymic clonal deletion of T cells that have receptors for those self antigens that are presented on hematopoietic cells. The mechanisms of tolerance induction to antigens not expressed in the thymus remain unclear. Tolerance to self antigens can be generated extrathymically through the induction of clonal nonresponsiveness in T cells with self-reactive receptors. A second mechanism of extrathymic tolerance was identified: clonal elimination of mature T cells with self-reactive receptors that had previously displayed functional reactivity.     

成体干细胞的可塑性

传统观念认为,成体干细胞只能分化成其自身来源组织的细胞类型。但近年大量的研究表明,成体干细胞可跨系甚至跨胚层分化成在发育上与之无关的其他组织的细胞类型,即具有可塑性。文章对成体干细胞可塑性的研究结果、分化机制、应用前景及需解决的问题等进行了综述。     

Commitment of mouse fibroblasts to adipocyte differentiation by DNA transfection

Cells of the mouse cell line 3T3-F442A can be induced by various hormones to differentiate into adipocytes, whereas cells of 3T3-C2, a subclone of 3T3, cannot. However, transfection of DNA from uninduced 3T3-F422A cells into 3T3-C2 cells permits recovery of 3T3-C2 transfectants that differentiate into adipocytes in the presence of insulin. DNA isolated from human fat tissue, when transfected into 3T3-C2 mouse cells, also gives rise to mouse transfectants that are induced to differentiate into adipocytes by the addition of insulin. Apparently, transfection of a trans-regulatory gene (or genes) from 3T3-F442A or human fat cells into 3T3-C2 cells is sufficient to commit 3T3-C2 cells to adipocyte differentiation.     

梅花鹿激活素A重组蛋白真核表达、纯化 及其生物活性的测定

【目的】体外真核表达梅花鹿（Cervus nippon）激活素 A重组蛋白并测定其生物活性,为进一步明确激活素 A在梅花鹿卵母细胞体外成熟过程中的生理学功能提供基础。【方法】利用RT-PCR技术克隆梅花鹿激活素βA (Activin βA, ACTBA)亚基基因的cDNA 全长序列,同时利用生物信息学对梅花鹿激活素βA的基因特征进行分析。在NCBI 数据库下载其他物种激活素βA同源序列,利用Clustalx和MEGA 4 软件进行同源比对并构建进化树。构建pcDNA4/ACTBA重组质粒并转染至CHO细胞内,进行目的蛋白的体外表达。采用免疫荧光及Western blot 技术对目的蛋白表达情况进行检测,并通过Ni-NTA 亲和层析柱对蛋白产物进行纯化。采用Western blot检测了梅花鹿激活素 A重组蛋白处理后的猪颗粒细胞中的SMAD2和SMAD3的磷酸化水平。最后采用荧光定量PCR及Western blot检测了梅花鹿激活素 A重组蛋白处理后的猪颗粒细胞中类固醇激素合成相关酶的表达量。【结果】克隆得到的梅花鹿ACTBA亚基基因含有1 278 bp 的碱基,编码426个氨基酸。同源性比较发现梅花鹿ACTBA基因与牛的ACTBA基因同源性最高达98.4%同源。进化分析表明该基因与同为偶蹄目动物的反刍兽牛和山羊亲缘关系最为接近。经酶切、PCR和测序方法鉴定,成功构建真核表达质粒pcDNA4/ACTBA。免疫荧光显示该质粒在CHO细胞中主要定位在细胞质。Western blot 结果显示激活素 A的前体蛋白分子量约为58 kD左右。镍亲和层析纯化后的激活素 A重组蛋白显著增加SMAD2和SMAD3的磷酸化,表明激活素 A可以激活SMAD信号通路。同时成熟的激活素 A重组蛋白可以诱导猪颗粒细胞芳香化酶(Aromatase)蛋白表达量上调,类固醇生成急性调节蛋白(steroidogenic acute regulatory protein, StAR)表达量下调,FSH受体基因表达量升高,LH受体基因表达量降低,但胆固醇侧链裂解酶(Cholesterol side-chain cleavage enzyme, CYP11A1 or P450scc)及3β-羟基类固醇脱氢酶(3β-Hydroxysteroid dehydrogenase, 3β-HSD)基因表达量不变。结果表明梅花鹿激活素 A重组蛋白可以增强FSH对颗粒细胞的生物学作用,也可以减弱LH对颗粒细胞的生物学作用。【结论】成功构建了激活素 A蛋白的真核表达载体,并获得了较高纯度的、具有生物学活性的梅花鹿激活素 A重组蛋白,为下一步激活素 A蛋白的生物学功能和生理学机制研究奠定了基础。     

重组犬IFN-γ在HEK293T细胞中的表达

为了建立一套犬IFN-γ(cIFN-γ)在HEK293T细胞中表达的方法,用伴刀豆球蛋白A(ConA)刺激犬脾细胞,通过RT-PCR方法从脾细胞中扩增犬IFN-γ基因,并将其克隆到pcDNA3.1A载体中,构建的真核表达载体pcDNA3.1A-cIFN-γ经磷酸钙介导转染HEK293T细胞进行表达。结果表明:克隆的犬IFN-γcDNA基因与GenBank上发表的序列一致,同源性100%。表达产物经Western-blot方法检测,证明克隆的犬IFN-γ基因能够在HEK293T细胞中进行表达,并且表达产物能够分泌到细胞外。     

Embryonic and neoplastic cell surfaces: availability of receptors for concanavalin A and wheat germ agglutinin

Embryonic tissue cells dissociated with ethylenediaminetetraacetate are readily agglutinated by the carbohydrate-binding protein concanavalin A. In this property, they resemble transformed, neoplastic cells; and they differ from untransformed adult cells, which are agglutinated by concanavalin A only after their receptors are unmasked by proteolytic treatment. Receptor sites for wheat germ agglutinin are also present on the surface of embryonic cells, but in a masked form, as on untransformed adult culture cells; they can be unmasked by treatment of the cells with trypsin. Concanavalin A binding sites on embryonic cells may function in cell contact and cell organization during embryonic morphogenesis and differentiation and later become masked in adult cells. The unmasking of these sites in neoplastic cells may represent a return, in this respect, to a condition resembling that of embryonic cells and may be related to cell mobility associated with infiltration and metastasis.     

Phagocytosis of Candida albicans enhances malignant behavior of murine tumor cells

Murine tumor cells were induced to phagocytize either Candida albicans or group A streptococcal cells. The presence of microbial particles within the tumor cell cytoplasm had no effect on in vitro tumor cell growth. However, when Candida albicans-infected tumor cells were injected into syngeneic mice, they formed tumors that grew faster, invaded the surrounding normal tissue more rapidly and metastasized more rapidly than control tumor cells. Tumor cells infected with group A streptococcal particles did not grow faster or show increased malignant behavior. These data indicate that the in vivo behavior of malignant tumor cells can be modulated by microbial particles, which are often present in the microenvironment of the growing tumor.