分枝杆菌简化琼脂培养基的研究

报道三种组分简单、制备方便的简化琼脂培养基.试验结果表明:7个标准菌株在简化琼脂培养基309A和309C上的生长速度和数量均相似或优于改良罗氏培养基和92号土豆汤琼脂培养基.简化琼脂培养基309C和309A可用于结核杆菌分离和药敏试验.     

土豆汤琼脂培养基培养分枝杆菌的研究

本文报道了一种土豆汤琼脂培养基系统,试验过的16株各群分枝杆菌都能在该培养基上生长。大多数分枝杆菌在土豆汤琼脂培养基上的初生长时间快于罗氏培养基。分枝杆菌H_(37)R_v、鸟型,胃型、堪萨斯、脓肿、不产色和偶发等标准株,在一些土豆汤琼脂培养基上产生两种不同的菌落。初步的研究表明,土豆汤琼脂培养基还可用于胸水、痰内结核杆菌的培养。土豆汤琼脂培养基系用传统的琼脂培养基制作方法,价格低廉,适合在发展中国家的实验室和国内医院检验科推广使用。     

卡介苗ERP基因缺失突变株在小鼠体内毒力的研究

为初步研究卡介苗ERP基因缺失突变株对小鼠的毒性作用,将卡介苗ERP基因缺失突变株和BCG分别皮下接种BALB/c小鼠后,取小鼠脾脏和肺脏匀浆,将匀浆液稀释后接种于罗氏培养基,培养3周后计菌落数(CFU);同时观察肺部病理改变,并比较和分析免疫16周时各组小鼠肺、肝、脾的脏器系数.结果表明,卡介苗ERP基因缺失突变株较BCG对BALB/c小鼠毒性低.     

结核分枝杆菌在自制培养基上快速生长初步观察

观察结核分枝杆菌标准株在5种自制培养基上的生长时间及最佳实验条件。将改良罗氏基的成分及传统的实验条件进行改进自制5种培养基,观察结核分枝杆菌标准株生长情况。并以第5号培养基3种成分不同浓度,做正交叉实验。结核分枝杆菌标准株在5种自制培养基上,菌落开始生长天数及典型菌落出现天数均比改良罗氏培养基短,两者差异均具有显著性(P<0.01)。第5号培养基以25%牛肉浸液,20%当归煎液,20%党参煎液的浓度最佳,结核分枝杆菌接种后第3~5 d开始生长,第7~9 d出现典型的“菜花状”菌落。结核分枝杆菌标准株在自制第5号培养基上生长快,培养时间短,为该菌培养提供了一种新的快速培养基,值得进一步研究。     

金霉菌的生理与金霉素的生产 I.接种培养基对于金霉菌的代谢及抗生素产量的影响

将金莓菌的芽孢接种到不同的接种培养基中,24小时后再接种到同一的酦酵培养基上,发现金霉素的产量有显著不同。一个好的接种培养基比一个坏的接种培养基所生的菌体在酦酵过程中产生的金霉素可以大出7至8倍。接种培养基的 pH 值对于以后菌体在酦酵培养基中金霉素的生产也有显著的影响。接种培养基并不显著地影响菌体在酦酵培养基上的生长,但已显然变更了它的代谢作用。由不同接种培养基中萌生的菌体,在同一酦酵培养基中醣的利用率不同,氧化的能力不同,有机酸的形成和堆积也不同,它们对于一些金属元素的反应也不一样。这个研究证明了金霉菌的初期的培养环境,对于以后菌体的发育和金霉素的生产有极大的影响。同时亦指出了金霉菌的发育在不同时期需要不同的环境,有着不同的代谢类型。去掌握这个生物规律——环境条件和发育的过程,是正确的研究方向,是提高抗生素产量的必要途径。     

分枝杆菌全合成琼脂培养基的研究

本文报道了一种适合常见致病分枝杆菌生长的全合成固体琼脂培养基体系。它为实验室研究分枝杆菌的营养生理、生化特性、遗传变异、药理和耐药机制提供了一种新工具,也为研制更加满意的分枝杆菌培养基创造了条件。试验过的大多数非典型分枝杆菌,在全合成琼脂培养基上比在罗氏培养基上生长快,生长量少于或等于罗氏培养基。标准牛型株的细胞群体中,仅有少量细胞能在全合成琼脂培养基上生长。鸟型．胞内和偶发等分枝杆菌标准株在全合成琼脂培养基上产生两种不同的菌落。     

抗菌肽及其功能研究

抗菌肽是近年来发现的广泛存在于自然界的一类阳离子抗菌活性肽,越来越多的证据表明它们在宿主先天性免疫和适应性免疫中有着重要的作用。对抗菌肽的研究正不断深入。本文先从抗菌肽研究的历史背景出发,简要介绍了抗菌肽的一般特性;然后从抗菌肽的直接抗菌活性和免疫调节功能这两个方面重点阐述其在宿主防御过程中的作用,最后对抗菌肽的临床应用及前景做了一个概述。     

卡介苗接种

本世纪初,Calmette和Guerin就观察到结核杆菌在含有公牛胆汁的培养基上生长可以防止菌群失去其毒力,用这个方法经多年传代培养之后,于1921年建立了稳定的减毒新菌株,这就是熟知的卡介苗(Bacille Calmette—Guerin即,BCG)。1930年,在吕北克地区发生了不幸事故,给儿童接种了用强毒菌株制造之菌苗,使他们中的73人死亡;因此不得不推迟了BCG的广泛应用。确实,由于过分地谨慎使BCG在英国     

藏红花细胞悬浮培养体系的建立及优化

基于诱导的藏红花细胞系,通过摇瓶法,优化了其液体培养基、接种量和种龄等培养条件,以建立藏红花细胞悬浮培养体系。结果表明,将生长在固体培养基上的藏红花愈伤组织接种在MS液体培养基(添加了2mg/L2,4-D,1mg/L6-BA和300mg/LCH)中,于(22±0.3)℃,120r/min的摇床上,暗培养30d,便可获得藏红花的悬浮细胞系。经优化其培养基、接种量和种龄,将种龄为20d的细胞系,按照5%接种量接种在液体B5培养基(添加了2mg/LNAA,1mg/L6-BA和300mg/LCH)中,于(22±0.3)℃,120r/min的摇床上,培养36d,细胞生物量(13.4g/L)和藏红花素产量(0.91g/L)均达到最高。本研究建立的藏红花细胞悬浮培养体系为其生物反应器放大培养奠定了基础。     

重组magainin抗菌肽表达条件的优化及其对抑菌活性的影响

对magainin抗菌肽重组酵母菌的摇瓶发酵条件进行了优化。结果表明 :当重组酵母菌在BMGY培养基中增殖至OD₆₀₀ 为 5～ 6时转接BMMY培养基 ;BMMY培养基pH值为 6.0 ,表达后期pH值控制在 3.0 ;2 6℃培养 48h ;补加 0.5 %甲醇的同时补加 3%营养液 ;可提高magainin抗菌肽的表达量。优化后摇瓶发酵的表达量可提高到 195 μg/ml。     

Inhibition of growth of tubercle bacilli by ali-esterase inhibitors in various culture media

Summary The effect of the potent ali-esterase inhibitor E 600 (paraoxon) on the growth of tubercle bacilli is potentiated by the addition of Tween 80 to the medium. This may be due to a change in the permeability of the bacteria for the inhibitor. Growth of tubercle bacilli from sputa is also inhibited by E 600 in the haemolysed human blood medium of Price. Cultures of tubercle bacilli in media with E 600 begin to grow after some time, when the inhibitor has broken down. The results obtained by the method of Price indicate that growth of the cultures does not originate from a few resistant cells but from the whole population which may have regained the ali-esterase activity essential to their growth.     

Effect of various peptides on the growth of Mycobacterium tuberculosis

Ten oligopeptides containing asparagine, glutamic acid, leucine or alanine on growth of Bacillus tuberculosis were tested. The experiments were performed on AS medium free of peptones. Bacterial suspensions were inoculated and the number of colonies and rapidity of bacilli growth under an influence of peptides tested was compared. Out of peptides studied and their different combinations the best turned to be combination of 0.01% glutathione +0.002% Gly-Asn + 0.0033% Leu-Gly. This combination allowed to appear on average 46% colonies more than on medium without peptides and first growth of tubercle bacilli was seen on average 3.2 days earlier than on medium free of peptides. Addition to the medium containing three above listed peptides of 0.1% of Bacto Tryptone (Difco) caused an increase of 127% of colony number of tubercle bacilli and their growth appeared 1.7 day earlier as compared to growth on medium containing these three peptides.     

On the Etiology of Sarcoidosis

Bacteriophages lytic for tubercle bacilli were isolated from tuberculous patients and patients with sarcoidosis. While tuberculous patients were found to raise phage-neutralizing antibodies, those with sarcoidosis appeared unable to do so. In vitro experiments showed that in the absence of neutralizing antibodies, phagolysis and lysogenic conversion of tubercle bacilli proceed. Lysogenic conversion results in the emergence of bacilli so modified in their morphological and antigenic properties that, on the basis of the classical bacteriological criteria, they can no longer be recognized as tubercle bacilli. From six lymph node biopsies collected from patients with sarcoidosis and cultured on a variety of media, including media containing anti-phage sera, five variant strains of tubercle bacilli were isolated. These observations support the view that certain cases of sarcoidosis are due to “modified” tubercle bacilli.     

羟基酪醇抑菌活性及抑菌稳定性研究

本研究探究了羟基酪醇对大肠杆菌、金黄色葡萄球菌、铜绿假单胞杆菌和枯草芽孢杆菌等四种供试菌的抑菌活性及抑菌稳定性。采用试管半倍稀释法确定MIC和MBC,并探讨羟基酪醇对供试菌的生长和细胞膜完整性的影响以及在不同介质下的抑菌稳定性。结果表明,羟基酪醇对大肠杆菌、金黄色葡萄球菌、铜绿假单胞杆菌和枯草芽孢杆菌的MIC分别为0.625、0.625、1.250、2.500 mg/mL,MBC分别为1.250、1.250、2.500、5.000 mg/mL。与对照组相比,四种供试菌核酸和可溶性蛋白泄漏显著,细胞膜的完整性被破坏。在不同NaCl浓度下,羟基酪醇对枯草芽孢杆菌的抑菌活性稳定;在1.0%和2.0%NaCl浓度下,羟基酪醇对大肠杆菌和铜绿假单胞杆菌的抑菌活性稳定;在2.0%NaCl介质下低浓度的羟基酪醇对金黄色葡萄球菌的抑菌活性稳定,在0.5%、1.5%和2.0%NaCl介质下高浓度的羟基酪醇对金黄色葡萄球菌的抑菌活性稳定。在蔗糖介质中,羟基酪醇对四种供试菌的抑菌活性均不稳定。因此,羟基酪醇可以作为一种新型的防腐剂。     

Antibacterial potential of hGlyrichin encoded by a human gene

Emerging multidrug‐resistant (MDR) bacteria are an enormous threat to human life because of their resistance to currently available antibiotics. The genes encoding antibacterial peptides have been studied extensively and are excellent candidates for a new generation of antibiotic drugs to fight MDR bacteria. In contrast to traditional antibiotics, antibacterial peptides, which do not cause drug resistance, have an unparalleled advantage. However, because most antibacterial peptides originate in species other than humans, the hetero‐immunological rejection of antibacterial peptides is a key disadvantage that limits their clinical application. In this study, we identify hGlyrichin as a potential human antibacterial polypeptide. The hGlyrichin polypeptide kills a variety of bacteria including the MDR bacteria methicillin‐resistant Staphylococcus aureus, MDR Pseudomonas aeruginosa, and MDR tubercle bacillus. A 19 amino acid peptide (pCM19) at positions 42–60 of hGlyrichin is crucial for its antibacterial activity. The hGlyrichin polypeptide kills bacteria through the destruction of the bacterial membrane. In addition, all peptides that are homologous to hGlyrichin have antibacterial activity and can penetrate the bacterial membrane. Importantly, hGlyrichin does not cause hemolytic side effects in vitro or in vivo. Therefore, based on the virtues of hGlyrichin, i.e., the absence of hetero‐immunological rejection and hemolytic side effects and the unambiguous efficacy of killing pathogenic MDR bacteria, we propose hGlyrichin as a potential human antibacterial polypeptide. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.     

从Granulysin抗菌机理出发合理设计抗菌肽

Granulysin是一种表达于人体毒性T淋巴细胞中的抗菌蛋白,其作用相当于广谱抗菌素。随着分子模拟技术的发展,人们已经初步掌握了其结构与功能的关系,有关这方面的研究也取得了较大的进展。根据Granulysin的覆膜作用机理重新设计出具有活性的抗菌小肽,并通过实验对该片段的活性进行检验。     

抗菌肽的研究进展

抗菌肽是一大类具有新型抗菌机理的抗生素,本文综述了抗菌肽的分类情况,抗菌肽的作用机制,以及部分正在开发的抗菌肽品种。     

Obtaining hybridomas producing monoclonal antibodies with different specificities against Mycobacterium tuberculosis of the human and bovine types

A procedure for isolation of hybridomes producing monoclonal antibodies (McAB) to tubercle bacilli is described. Specificity of the McABs was studied with the solid phase radioimmune and immunoenzyme tests. Supernatant of tubercle bacilli destroyed with ultrasound was used as antigens. The McABs did not practically react with antigens of the tubercle bacilli atypical forms. Five ascitic monoclonal hybridomes were isolated. Four of them produced antibodies with selective specificity to antigens of bovine tubercle bacilli (M. bovis-8 and BCG) and one produced antibodies to antigens of human tubercle bacilli (H37Rv).     

Comparison of Methods for Tuberculosis Bacteriology

To improve efficiency of isolation of tubercle bacilli from clinical specimens, the following recommendations are presented. (i) Employ multiple specimens consisting of a combination of morning sputums for the early detection of positives, along with 24-hr sputum pools for the greatest total yield of positives. (ii) When timing is rigorously controlled, Zephiran-trisodium phosphate and sodium hydroxide-acetylcysteine are comparable, but if timing cannot rigidly be controlled, employ the Zephiran-trisodium phosphate digestion procedure to allow the greatest freedom in exposure time with the lowest kill rate to tubercle bacilli. (iii) Employ both an agar medium incubated in 5% CO₂, for the early detection of positives as well as positives in the presence of contaminants, and an egg medium, preferably with CO₂, to increase the yield of positives.     

Automated identification of tubercle bacilli in sputum. A preliminary investigation

OBJECTIVE: To use an automated method to detect tubercle bacilli in sputum specimens. STUDY DESIGN: Using fluorescence microscopy, tubercle bacilli were identified on auramine-stained sputum specimens. Images were then captured with a digital camera and enhanced through imaging processing techniques. The bacilli were recognized using neural network classifiers. RESULTS: This preliminary investigation demonstrated a sensitivity of 94.1% for the identification of individual bacilli. As there are usually fairly numerous tubercle bacilli in the sputum of patients with active pulmonary tuberculosis, the overall diagnostic accuracy of sputum smear-positive patients can be expected to be very high. CONCLUSION: Potential benefits of automated screening for TB bacilli are: rapid, accurate, inexpensive diagnosis; the ability to screen larger numbers of people; increased resources to monitor patients; and reduction in health risks to staff.