电诱导细胞融合仪的研制及在真菌原生质体融合中的应用

细胞融合仪是进行细胞融合研究的核心装置。作者研制出一种性能参数较好而造价低廉的电诱导细胞融合仪。其输出交流电场频率及电压峰峰值分别为０．５－４．０ＭＨｚ和０－７０Ｖ;脉冲时程和幅度分别为４－１００μｓ和０－５００Ｖ;带负载能力大于几种国内外产品。用本装置对香菇和丝核菌原生质体进行了融合诱导,对电场诸参数与融合效果之间的关系进行了探讨。结果表明本装置性能稳定,使用效果不次于进口日本产品,可用于真菌、细菌或植物的细胞融合研究。     

分子生物学实验课程中自行设计实验的实践

自行设计实验报告是学校分子生物学实验课程考核体系的一个重要内容,由学生以小组的形式分工合作完成。报告设计的实验方案在全班进行讨论和修改,最后确定一套切实可行的实验方案。学生参与自行设计实验的每一个环节,包括试剂的选择与订购、器皿耗材的准备、试剂的配制、实验的操作和结果的处理分析等等。该实验增加了实验教学的主动性、创新性、系统性和高效性。这一研究过程拓宽了学生的知识面、提高了学生解决问题的能力,同时积累了科研工作的经验,为进入研究生阶段的工作奠定基础。     

谈细胞生物学启发讨论式教学中的问题设置

启发讨论式教学是素质教育对各科教学的新要求。问题设置是启发讨论式教学中的关键环节。探讨了细胞生物学启发讨论式教学中问题设置的基本方式及其应注意的几个方面。     

A New Class of Completely Self‐Designing Clinical Trials

A flexible method is proposed for group sequentially performed clinical trials which allows for an adaptive, data‐driven sample size reassessment at each stage. By also adaptively assigning different weights to the several stages the total number of study parts can be steered to an intended early or late end of the trial in dependence on all information available prior to a stage. Although at each stage the null hypothesis is tested on rejection, the full level‐α‐test is preserved at the end of the study. The proposed method is not restricted to normally distributed responses. The discussed adaptive designing is a useful tool provided that a priori information about parameters involved in the trial are not available or subject to uncertainty. The presented learning algorithm enables the complete self‐designing of a study.     

改造的蜂毒素基因在毕赤酵母中分泌表达及培养条件研究

对蜂毒素基因进行改造后,通过PCR方法获得新蜂毒素基因(MEA),将其克隆到表达载体pPICZa—A,而后将重组表达载体pPICZa-A-MEA转化GS115,筛选获得重组酵母菌．对GS115-ME经甲醇诱导表达并对培养条件进行优化探讨．对改造的蜂毒素进行了溶血活性、热稳定性及酸碱稳定性测定．结果表明,蜂毒素基因成功地在毕赤酵母中表达,经改造的蜂毒素在保留了抗菌活性的同时溶血活性降低20倍左右,同时还具有良好的热稳定性和酸碱稳定性．     

图位克隆技术新型遗传学实验教学项目的设计与实践

染色体重组与连锁互换是遗传学教学的重点和难点。为使学生更好地理解此方面知识, 我们课题组前期利用图位克隆(map-based cloning)技术, 克隆了1个调控水稻(Oryza sativa)类病变表型的基因SPL5, 并基于此设计了一个新的综合型遗传学实验, 即利用DNA分子标记对基因进行定位。实验中学生利用水稻spl5突变体与野生型杂交获得的F₂代定位群体和多态性分子标记, 对spl5突变进行染色体连锁分析、初步定位和遗传作图。该教学实验不仅可有效促进学生对遗传学三大定律的理解, 而且对其开阔视野、提高解决问题和团队协作的能力也有促进作用。     

Optimum Designs for Estimating the Variance Components in a Simple Variance Component Model (Model II), I

The methods of optimal designing of experiments proposed by WALD (1943) are used for determination of an A_σ2-optimal concrete design for estimation of σ^2′ = (σ, σ) in case of one-way analysis of variance. Starting point of definition of the optimality criterion is a quadratic loss matrix.     

The House Building of Caddis Larvae: A Source of Projects for Schools

Protoplasmic streaming (cyclosis) in plant cells has long been presented as a purely qualitative exercise in microscopy. Using simple formulae, it is possible to determine the energetics of this process (in terms of ATP hydrolysis) and its relation to the total energy expenditure of the plant cell. This exercise can provide a valuable integration of physicochemical principles and microscopical observation.     

A novel strategy of epitope design in Neisseria gonorrhoeae

In spite of genome sequences of both human and N. gonorrhoeae in hand, vaccine for gonorrhea is yet not available. Due to availability of several host and pathogen genomes and numerous tools for in silico prediction of effective B-cell and T-cell epitopes; recent trend of vaccine designing has been shifted to peptide or epitope based vaccines that are more specific, safe, and easy to produce. In order to design and develop such a peptide vaccine against the pathogen, we adopted a novel computational approache based on sequence, structure, QSAR, and simulation methods along with fold level analysis to predict potential antigenic B-cell epitope derived T-cell epitopes from four vaccine targets of N. gonorrhoeae previously identified by us [Barh and Kumar (2009) In Silico Biology 9, 1-7]. Four epitopes, one from each protein, have been designed in such a way that each epitope is highly likely to bind maximum number of HLA molecules (comprising of both the MHC-I and II) and interacts with most frequent HLA alleles (A*0201, A*0204, B*2705, DRB1*0101, and DRB1*0401) in human population. Therefore our selected epitopes are highly potential to induce both the B-cell and T-cell mediated immune responses. Of course, these selected epitopes require further experimental validation.     

Anti hyperglycaemic study of natural inhibitors for Insulin receptor

Diabetes is a metabolic disorder associated with either improper functioning of the beta-cells or wherein cells fail to use insulin properly. Insulin, the principal hormone regulates uptake of glucose from the blood into most of the cells except central nervous system. Therefore, deficiency of insulin or the insensitivity of its receptors plays a key role in all forms of diabetes. In the present work, attempt has been made to find out plant sources which show anti hyperglycaemic activity (AhG) (i.e. compounds that bring down the blood glucose level in the body). Ayurvedic plants showing AhG activity formed the basis of our study by using the platform of Computer Aided Drug Designing (CADD). Among 600 plants showing AhG activity, 500 compounds were selected and screened, out of which 243 compounds showed drug likeness property that can be used as therapeutic ligand/drug. Initial screening of such compounds was done based on their drug likeness or biochemical properties. Dynamic interaction of these molecules was captured through Protein-Ligand study. It also gave an insight of the binding pockets involved. Bench marking of all the parameters were done using the diabetic inhibitor drug, Glipizide. Pharmacokinetic studies of the compounds such as Aloins, Capparisine, Funiculosin and Rhein exhibited less toxicity on various levels of the body. As a conclusion these ligands can lay a foundation for a better anti-diabetic therapy.

Abbreviations

AhG - Anti hyperglycaemic, CADD - Computer Aided Drug Designing.