一个实用的制备EMBL4 DNA 的方法

以往人们通常用氯化铯梯度超速离心法、甘油梯度超速度离心法等方法纯化噬菌体。采用这些方法,虽然可以获得纯净的λ噬菌体颗粒。但需要昂贵的试剂和仪器。操作也冗长繁琐。我们采用并改进了Reddy的方法,首先用DE_(52)纤维素柱层析纯化λ噬菌体颗粒,然后用酚抽提,从提纯的噬菌体中分离DNA,这个方法简单快速,不需要氯化铯梯度超速离心,也不使用SDS、蛋白酶和核酸酶。     

一种简便的肌醇磷脂微量分析方法

分析磷脂酰肌醇循环(PI cycle)的磷脂组分常采用双向薄层层析法．建立了一个简单快速的单向薄层层析分离肌醇磷脂方法．首先采用不同的有机溶剂体系分别提取非多磷酸肌醇磷脂和多磷酸肌醇磷脂,然后用不同的层析展开体系,对两部分磷脂进行单向薄层层析分离．采用无载体 ³²P标记实验对该方法分离效果进行了观察．此法适用于同位素标记和非标记样品中肌醇磷脂组分的比较分析及多磷酸肌醇磷脂的提取、纯化和定量．     

一种简单、快速提取DNA的方法

随着分子生物学研究的迅速发展,提取ＤＮＡ已成为一项常规实验。用经典方法提取ＤＮＡ［１］,先用蛋白酶Ｋ、ＳＤＳ消化,然后用酚、氯仿抽提,乙醇沉淀,耗时较多,提取液需要多次转移,易引起交叉污染和ＤＮＡ丢失。本文利用硅藻（ｄｉａｔｏｍ）能够特异性吸附核酸的...     

A Rapid and Simple Method for Assaying Interferon1

A new procedure of assaying interferon (IF) has been developed. Cell suspension was dispensed into liquid scintillation counting vials together with IF sample. During an overnight incubation, the cells adhered sufficiently to the bottom of the vials and all the subsequent procedures were carried out without transfer of the cells from the vials. Vesicular stomatitis virus was inoculated and virus-specific RNA was labeled by adding ³H-uridine and actinomycin D to the medium. Incubation was terminated prior to completion of a single-step growth of the virus and radioactivity of the labeled cells in each vial was determined. The reciprocal of the IF dilution which reduced the radioactivity in viral RNA by 50% was taken as the titer. The present procedure consists of simple manipulations and can be completed within 24 hr. Furthermore, it is quite reproducible and gives a titer almost identical to that obtained by the conventional plaque-reduction dose method. The procedure can be applied to mouse L cells, rabbit RK-13 cells and human FL cells, without modification.     

Gas Phase Oxidants of Cigarette Smoke Increase Nitric Oxide Synthase and Xanthine Oxidase Activities of Rabbit Brain Synaptosomes

In the present study we demonstrated that NO synthase and xanthine oxidase of synaptosomes isolated from rabbit brain cortex can be activated by the gas phase of cigarette smoke to produce nitric oxide and superoxide which react together to form peroxynitrite. Expose of synaptosomes, up to 3 hours, in the gas phase of cigarette smoke, a gradual increase in both nitric oxide and superoxide release that were inhibited by N-monomethyl-L-arginine (100 M) and oxypurinol (1 mM), respectively, was observed. NO synthase and xanthine oxidase activities were increased approximately three fold after treatment of synaptosomes with the gas phase of cigarette smoke as compared with the gas phase deprived of oxidants. Synaptosomes treated with the gas phase of cigarette smoke dramatically increased 3-nitrotyrosine production (used as an index of peroxynitrite formation). Synaptosomes treated with the gas phase of cigarette smoke, promptly increased malondialdehyde production with subsequent decrease of synaptosomal plasma membrane fluidity estimated by fluorescence anisotropy of 1,4-(trimethyl-amino-phenyl)-6-phenyl-hexa-1,3,5-triene. Gas phase deprived of oxidants showed a small but not statistically significant (p > 0.05) effect on both malondialdehyde and membrane fluidity. In summary, the present results indicate that activation of NO synthase and xanthine oxidase of brain cells by oxidants contained in the gas phase of cigarette smoke lead to the formation of peroxynitrite a causative factor in neurotoxicity.     

一种简便快速的制备水稻基因组DNA PCR模板的方法

目的：发展一种简便快速的制备水稻基因组DNA PCR模板的方法。方法：用枪头捣碎水稻叶片代替液氮研磨法提取水稻基因组DNA作PCR模板,在去污剂SDS和表面活性剂TrionX-100的存在下在沸水中煮沸10min,然后取上清扩增微管蛋白（TubA1）基因内含子。结果：发现在利用煮沸法提取水稻基因组DNA的过程中,用枪头捣碎叶片可代替液氮碾磨,加入0.1%表面活性剂TrionX-100煮沸叶片对制备模板有促进效果,得到了预期的PCR片断。结论：该方法快速、简便、经济,具有良好的重复性与特异性,便于自动化。     

一种简便快速筛选重组子的方法

目的：根据碱裂解法抽提质粒DNA的原理,研究应用快检缓冲液方法挑取重组子克隆,从而获得简单易行,快速方便,节省时间,提高工作效率的筛选重组子的方法。方法：不需抽提质粒,只要将菌落接入快检缓冲液后直接进行普通琼脂凝胶电泳分析,就可以快速筛选出重组子。结果：结果和提取质粒酶切鉴定结果一致。结论：经实验证明用快检缓冲液方法筛选重组子是一种简单易行,快速方便,节省时间,提高工作效率并且可靠的方法。     

一种简便快速的聚合酶活性实时检测新方法

基于双链DNA结合染料能特异嵌入双链DNA发出荧光的原理,发展了一种实时检测DNA聚合酶活性的简便方法.在检测过程中,聚合酶的聚合反应进程被实时转换为荧光信号,通过监测荧光强度的变化实时检测聚合酶的活性及药物对聚合酶活性的影响.该方法不需要对DNA进行放射性同位素标记和荧光标记,也不需要聚丙烯酰胺凝胶电泳和聚合酶链式反应,是一种简便、快速的聚合酶活性实时检测新方法,为研究抗肿瘤药物对聚合酶活性的影响提供了一种简捷方法,也将为相关疾病诊治和药物筛选提供一种新的思路.     

A Simple, Rapid Method for Demonstrating Bacterial Flagella

We developed a simple, rapid method for demonstrating flagellation of bacteria using the fluorescent protein stain NanoOrange (Molecular Probes, Eugene, Oreg.). The NanoOrange reagent binds to hydrophobic regions of proteins, which results in substantial enhancement of fluorescence. Unbound reagent is essentially nonfluorescent. NanoOrange fluorescently stained bacterial cell bodies, as well as flagella and other appendages, which could be directly observed by epifluorescence microscopy. Detection of flagella was further improved by using a charge-coupled device camera for image capture and processing. The reliability of the method was tested by using 37 pure cultures of marine bacteria. Detection of flagella on the isolates by NanoOrange staining was compared to detection by transmission electron microscopy (TEM). For 36 of 37 cultures, the two methods yielded the same results. In one case, flagella were detected by TEM but not by NanoOrange, although the difference may be attributable to differences between the culture preparations. NanoOrange staining is rapid (10 to 15 min) and does not require fixation or dehydration, so live samples can be stained. Since NanoOrange is a general protein stain and works directly in seawater, it may also prove to be useful for staining other proteinaceous material that is of interest to aquatic microbial ecologists.     

简便快速分离天花粉毒蛋白的一种方法

 简便快速分离天花粉毒蛋白的一种方法孙建忠,季瑞华,王克夷（中国科学院上海生物化学研究所,上海２０００３１）天花粉是由多年生草质藤本植物栝楼（ＴｒｉｃｈｏｓａｎｔｈｅｓｋｉｒｉｌｏｗｉｉＭａｘｉｍ,Ｃｕｃｕｒｂｉｔａｃｅａｅ）的块茎制成,天花粉毒蛋白是...     

A Simple and Accurate Method for Infra-Red Gas Analyser Calibration

An alternative method for calibrating infra-red gas analysersis described which uses gas mixtures prepared with a gas mixingcircuit constructed from commonly available materials. It isshown that the maximum error in the gas mixture is about 1.5%,and possible improvements to the technique are discussed. Key words: Infra-red gas analyser, Calibration     

A Simple Method for the Rapid Analysis of Animal Sounds

A simple, real-time method for displaying the information contained in the zero-crossings of acoustic signals is described. The method can be used even with many signals that have harmonics, and reveals a wealth of fine structure in bird song. Some of this structure may serve a communicatory function.     

一种简便快速的单引物PCR定点突变方法

为了解决在一些特殊位点上利用Quick Change方法进行定点突变时会在突变位点处额外插入引物序列导致突变失败的问题,对Quick Change法进行了改良。改良方法为:合成在突变位点处点突变的一对反向互补引物,分别进行单引物PCR扩增,将两种扩增产物混合,变性复性后加入Dpn I进行酶切,酶切产物转化大肠杆菌DH5α,抗性筛选阳性克隆进行测序验证。利用此法成功突变紫穗槐二烯合酶(amorpha-4,11-diene synthase,ADS)基因中多个利用常规方法突变均因引入额外引物而无法成功的特殊位点,证明此方法实践上可行,而且也可以避免插入额外引物序列,这也从侧面证明额外引物插入的原因是双引物同时反应。     

A Rapid and Simple Method for Staining Lipid in Fixed Nematodes

A method is described for staining lipid in fourth-stage dispersal juvenile nematodes fixed with formal-acetic fixative (FA4:1). Bursaphelenchus xylophilus fourth-stage dispersal juveniles were fixed with hot FA4:1 for 24 hours, excess fixative was removed, and a solution of saturated oil red O in 96% ethanol added and allowed to sit for 25 minutes at 60 C. Excess oil red O was removed, nematodes were washed twice with 70% ethanol, and were processed to pure glycerin. Lipid droplets within the nematodes were viewed by light microscopy and appeared as dark red spheres of various sizes. Computerized image analysis was used to quantify lipid droplet area.     

一种简单快速植物组织冰冻切片方法

比较不同冷冻方法对植物细胞超微结构的影响,结果表明:直接包埋法处理的植物细胞超微结构保存较好,而液氮冷冻处理的植物细胞内膜系统损伤严重.建立了一种直接包埋冷冻和适当回温相结合的方法,不仅可以制作出植物细胞基本结构保存完整的组织切片,而且避免了使用冰冻保护剂的弊端.其操作程序是:样品固定→冰冻与包埋→适当回温→快速切片→展片→染色.此法制作的切片可进行不同的染色和组织细胞化学测定,具有操作简便,易于推广的特点.     

A Rapid and Simple Method for DNA Preparation of Magnaporthe oryzae from Single Rice Blast Lesions for PCR-Based Molecular Analysis

Rice blast is one of the most destructive diseases of rice worldwide, and the causative agent is the filamentous ascomycete Magnaporthe oryzae. With the successful cloning of more and more avirulence genes from M. oryzae, the direct extraction of M. oryzae genomic DNA from infected rice tissue would be useful alternative for rapid monitoring of changes of avirulence genes without isolation and cultivation of the pathogen. In this study, a fast, low-cost and reliable method for DNA preparation of M. oryzae from a small piece of infected single rice leaf or neck lesion was established. This single step method only required 10 min for DNA preparation and conventional chemical reagents commonly found in the laboratory. The AvrPik and AvrPi9 genes were successfully amplified with the prepared DNA. The expected DNA fragments from 570 bp to 1,139 bp could be amplified even three months after DNA preparation. This method was also suitable for DNA preparation from M. oryzae strains stored on the filter paper. All together these results indicate that the DNA preparation method established in this study is reliable, and could meet the basic needs for polymerase chain reaction-based analysis of M. oryzae.     

A Simple and Rapid Wholemount Staining Method with Methyl Green-Pyronin G Applied to A Molluscan Brain Preparation

Subesophageal ganglia of molluses have been stained as whole mounts with methyl green-pyronin G to display the relative location of individual neurons. Nuclei appear blue, perikarya red. Expose the ganglion cells by dissection of the connective tissue in dl Ringer. Transfer the ganglion to a fixative of 2.5% glutaraldehyde in 0.1 M Na cacodylate pH 7.1 at 4 C for 12-24 hours, and wash in distilled water for 1 1/2 hours. Stain with methyl green-pyronin G for 1/2-1 hour ad differentiate in 96% ethanol wing many rapid changes. Transfer the ganglion to absolute ethanol for 2 1/2 hours and clear in xylene for 3 hours before embedding in Depex in a suitable dish. When the Depex has hardened, the preparation can be stored, and is readily available for subsequent examination. The method may be applicable to other invertebrate tissues, and may be useful in preparing objects for teaching purposes.     

一种筛选单体速效胰岛素的简便方法

通过基因突变方法制备的单体速效胰岛素Lispro Insulin已上市用于治疗糖尿病,如何利用简便快速的方法研究获得新的单体速效胰岛素成为研究的热点。以Lispro Insulin为模型,利用猪胰岛素的胰蛋白酶酶切大片段(DOI,去B链C端八肽胰岛素)和化学合成的八肽,通过胰蛋白酶的酶促合成方法为筛选新的单体速效胰岛素提供了新的途径。结果显示,酶促合成得到的95％纯度的Lispro Insulin具备了单体速效胰岛素的不自身聚合的特点。     

A Rat Model of Cigarette Smoke Abuse Liability

We sought to develop a rat model of cigarette smoke exposure (CSE) that created cotinine serum levels comparable to those of smokers and induced conditioned place preference (CPP) suggestive of cigarette smoke abuse liability. Rats were exposed to sidestream cigarette smoke delivered semicontinuously for 2 periods of 20 (group S20), 40 (group S40), or 60 (group S60) min daily for 12 wk. Serum cotinine concentration in blood samples was determined at 1 and 20 h after CSE. A biased (black versus white chamber) CPP paradigm was used. In the high CSE group (group S60), serum cotinine at 1 h (250 to 300 ng/mL) was comparable to average cotinine levels reported for addicted smokers (around 300 ng/mL). Cotinine levels at 20 h after CSE were higher than the smoker–nonsmoker cut-off value (greater than 14 ng/mL) in all smoking groups, with the S60 group having the highest levels. All rats preferred the black chamber to the white chamber during the preexposure CPP test. The time spent in the white chamber was increased compared with 0-wk values in group S40 at 8 wk, group S60 at 4 and 8 wk, and the control group at 4 and 8 wk but not at 12 wk; however, the shift in CPP was significantly higher at 8 wk in group S60 compared with other groups. In conclusion, interrupted 2-h daily CSE for 8 wk induced serum cotinine levels in rats comparable to those of smokers and induced CPP suggestive of cigarette smoke abuse liability.Abbreviations: CPP, conditioned place preference; CSE, cigarette smoke exposureThe devastating consequences of smoking on health have been studied extensively in numerous clinical and animal studies over time. This chronic habit leads to dependence on tobacco smoke, with nicotine, a main active ingredient of tobacco products, being recognized as the basic addictive substance.³²The known health benefits of smoking cessation motivate smokers to quit tobacco use. However, unaided efforts usually are unsuccessful, resulting in smoking relapse. The fight against nicotine addiction may be undermined by potential weight gain after smoking cessation, potentially discouraging those attempting to quit smoking and contributing to relapse. During the past few years, research has been focused on 2 main areas of interest toward this direction: understanding the underlying biologic mechanisms related to nicotine addiction to effectively design therapeutic strategies to support those who wish to quit smoking and investigating the hormonal and molecular mechanisms responsible for weight gain after smoking cessation.So far, animal models used to study the consequences of smoking cessation involved the administration of nicotine as a sole agent until addiction was achieved.²³ However, nicotine-administration models do not completely represent the toxic and addictive effects of cigarette smoke, given that smoke contains more than 4000 chemicals whose actions or coactions have not been thoroughly evaluated yet.¹ Cigarette smoke exposure (CSE) animal models have been used in studies investigating the metabolic changes conferred by smoking^10-12 but not in those after its cessation. In toxicity studies, animals are exposed to tobacco smoke for various periods, which depend on the side effect under investigation.^18,25,27 Smoke exposure timetables usually do not involve weekends for practical reasons, and addiction of animals to tobacco smoke is not assessed in current models.In our opinion, an ideal animal model of cigarette smoke abuse liability suitable for the study of smoking cessation resembles the clinical situation in terms of chronic daily inhalation of cigarette smoke sufficient to attain blood nicotine levels comparable to those of smokers and in cessation of the CSE period after achieving tobacco smoke abuse liability. In the present project, we sought to establish such a model in rats by defining the daily timetable of CSE to induce serum levels of cotinine, nicotine''s major proximate metabolite, comparable to those of smokers and by determining the minimum total CSE period required to induce abuse liability to cigarette smoke. We assessed the CSE period by using a biased conditioned place preference (CPP) paradigm.⁸