Behavioral modification in choice process of Drosophila

Because of its clear genetic and developmental background, diversity of behavioral paradigms and neuroanatomy of the brain, Drosophila has become an important animal model for studying genetic, molecular and cellular bases of learning and memory[1]. Extensive research has explored the visual operant conditioning of Drosophila and related molecular bases[2—8]; recently, researchers began to address cognition-like functions and involved neural substrates[9—11]. In these studies, behavioral ana…     

一种快速鉴定转基因植物纯合体的新方法

植物转化中鉴定转基因植物的整合性是一个很重要的步骤,常规方法是对独立分离的转基因T1代植株产生的T2代进行转基因分离比率研究,以检测T1代的转基因整合状态,不仅费时费力,而且浪费了T1代资源。本介绍一种应用双重定量实时PCR技术鉴定转基因植物纯合子的新方法：以T1代植物DNA为模板,根据转基因后代的Ct表型值鉴定其转基因整合状态,Ct值接近2的为转基因纯合型,Ct值接近1的为转基因杂合型。用这种方法,可以同时对数十个T1代转基因幼苗的整合状态进行快速鉴定,准确率为100％。     

光学分子影像技术及其在药物研发领域的应用

光学分子影像技术是一种发展迅速的生物医学影像技术,能够利用生物发光技术或荧光蛋白等,对生物体内特定的生物过程进行无创的定性或定量研究。应用该技术可以对药物进行筛选,选取具有潜在治疗效果的药物进行后续研究,而终止对可能无效药物的研究,同时可以评价药物对肿瘤的代谢、增殖、血管形成、凋亡和组织乏氧等方面的影响。本文主要介绍光学分子影像技术及其在药物研发,尤其是抗肿瘤药物研发领域的应用。     

Comparison of soil microbial communities from two distinct karst areas in Hungary

Karst areas belong to the most exposed terrestrial ecosystems, therefore their study have a priority task in Hungary, as well. The aim of this study was to compare the structure, activity and diversity of soil microbial communities from two distinct Hungarian karst areas (Aggtelek NP and Tapolca-basin). Soil samples were taken three times from 6 distinct sites, from different depths. Soil microbial biomass C (MBC), microbial biomass N (MBN), basal respiration (BRESP) and substrate induced respiration (SIR) were measured. The phylogenetic diversity of bacterial communities was compared by Denaturing Gradient Gel Electrophoresis (DGGE). The highest MBC, MBN, BRESP and SIR values were measured in the rendzina soil from Aggtelek. On the basis of biomass and respiration measurements, microbial communities differentiated mainly according to soil depths whereas DGGE profiles of bacterial communities resulted in groups mainly according to sampling sites.     

Bleomycin in the Reticuloses

Bleomycin alone was used in the treatment of 54 patients with Hodgkin''s disease in its later stages, 17 with generalized lymphosarcoma, 22 with reticulum cell sarcoma, and 7 with mycosis fungoides. The patients had had radiotherapy and full courses of conventional chemotherapy. Bleomycin was given in doses of 30 mg weekly to an average total dosage of 200 mg, though up to 800 mg could be given because of its marrow-sparing properties. Sixteen (29%) of the patients with Hodgkin''s disease remitted, most of them achieving only a partial remission, and similar results were obtained in the other three reticuloses. Bleomycin would seem to have some beneficial action in the late stages of Hodgkin''s disease, though it is less effective than some drug regimens recently introduced. Nevertheless it may be useful when there is diminished bone marrow reserve. It would be a suitable drug to use in combination therapy of these four reticuloses.     

乌头及其同属近缘种的SSR指纹图谱研究

乌头(Aconitum carmichaeli Debx.)为中国重要的药用植物,种质资源丰富,同属近缘种繁多。该研究采用SSR分子标记技术对采自17个种群的51份乌头样本和13个同属近缘种的65份样本进行扩增和聚丙烯酰胺凝胶电泳检测,分析了乌头及其同属近缘种的遗传多样性、遗传分化和系统发育关系,筛选出稳定性好、多态性高的SSR引物构建乌头及其近缘种的指纹图谱。结果表明:(1)11对乌头微卫星引物均表现出高的多态性,共检测出109个复等位基因,平均每个位点9.91。(2)乌头在物种水平上遗传多样性丰富(A=3.090 9,I=0.889 7,h=0.540 2),种群间的遗传分化显著(Gst=0.277 4);乌头属14种植物表现出了较高的遗传多样性(A=9.909 1,I=1.526 2,h=0.690 5),物种间遗传分化显著(Fst=0.437),基因流微弱(Nm=0.451 8)。(3)聚类分析表明,同一种群的乌头样本首先聚在一起各自形成小支,17个小支聚为一支;13个乌头近缘种材料中,相同物种的样本分别聚为一支;乌头属14个物种聚为5个大支,与形态分类结果一致。(4)利用基因型丰富、多态性高的6对SSR引物(Tchin03、Tchin04Tchin20、Tchin26、Tchin29、Tchin32)可有效区分14种乌头属植物,并以此建立了乌头种质资源和近缘种的DNA指纹图谱。该研究为乌头的种质资源鉴定及混伪品鉴定提供了重要的技术支撑。     

果蝇幼虫的视觉系统

视觉对于动物的生存和行为来说是非常重要的。虽然果蝇幼虫的视觉神经系统在组织结构上比成虫简单,但是也具有一定的复杂性和多样性。在最近几年中,随着对果蝇幼虫视觉系统功能的研究取得重要进展,我们对于果蝇幼虫视觉系统的认识更加丰富了。果蝇幼虫视觉系统的结构中,最初级的光感受神经元包括三类,一类是BO/BN(Bolwig's organ/Bolwig's nerve),一类是表达感光分子CRY(cryptochrome)的神经元,另外一类是Ⅳ型DA(classⅣdendriticarborization)神经元;果蝇幼虫视觉系统的次级神经元主要是光节律相关的侧神经元(lateralneurons,LN),它表达Per(period)、Tim(timeless)及Pdf(pigment dispersion factor)等节律相关的蛋白分子;而第三级神经元包括更为下游的、表达果蝇促胸腺激素且直接调控幼虫光偏好的NP394神经元。这三级神经元构成了我们现在所了解的果蝇幼虫视觉神经系统的基本框架。