结核分枝杆菌耐药检测及其临床意义

耐药结核病(TB)尤其是耐多药结核病(MDR-TB)、广泛耐药结核病(XDR-TB)的快速诊断和有效治疗是TB防控中亟需解决的难题。结核分枝杆菌(Mtb)耐药的主要机制是由于药物作用靶标或药物代谢酶编码基因突变所致。临床上常用的Mtb药物敏感性试验方法主要包括表型药敏方法和分子药敏方法,本文还简要地概述了通过药敏试验所揭示的一些值得临床医师关注的临床意义。     

抗结核药物靶点研究最新进展

近年来结核病又卷土重来,发病率与死亡率明显回升,并且结核菌的耐药问题也日趋严重,成为结核病临床治疗的棘手问题,而在过去的30年里未开发出新型高效的抗结核药物.因此发现潜在的新抗结核药物靶点,研究开发新型抗结核药物,以实现对结核病的有效控制迫在眉睫.文中阐明了抗结核药物与胞壁合成相关的新靶点、与抗耐药有关的新靶点、与核酸稳定性相关的靶点、与电子传递及氧化还原相关的靶点,研究未知作用机制有效物质而发现的新靶点以及与重要代谢途径中关键代谢酶相关的靶点等6个方面研究的新进展,对抗结核新药的研究具有重要指导意义.     

苏州地区532例结核病患者结核分枝杆菌对抗结核药物的耐药情况及其相关影响因素分析

目的:分析苏州地区结核病患者结核分枝杆菌对抗结核药物的耐药情况及其相关影响因素,为耐药结核病合理用药提供参考。方法:抽取2018年1—12月间收治的结核分枝杆菌培养结果呈阳性的532例患者资料,统计和分析结核分枝杆菌对利福平、链霉素、异烟肼、乙胺丁醇4种一线抗结核药物以及阿米卡星、左氧氟沙星、对氨基水杨酸、丙硫异烟胺4种二线抗结核药物的耐药性及其耐药的相关危险因素。结果:532例患者中分离出结核分枝杆菌532株,其中人型结核分枝杆菌529株,牛型结核分枝杆菌3株;532例患者一线和二线药物中至少对1种药物耐药的180例(33.83%),其对一线和二线药物均耐药的98例(18.42%);532例患者中,一线药物162例,其总耐药率为30.45%;其对4种一线药物的耐药率由高到低依序为链霉素(26.50%)>异烟肼(24.25%)>利福平(18.23%)>乙胺丁醇(6.39%);单耐药结核(MR-TB)占6.39%,多重耐药结核(MDR-TB)占17.10%,泛耐药结核(PDR-TB)占6.95%;532例患者中4种二线药物总耐药率为21.80%,耐药率最高的为对氨基水杨酸(16.16%)和左氧氟沙星(15.60%);泛耐多药结核(XDR-TB)为13.35%;经Logistic回归分析结果显示,复治患者年龄大于60岁是一线药物耐药的危险因素(P<0.05),而复治、流动人口、45～60岁和大于60岁患者是二线药物耐药的危险因素(P<0.05)。结论:苏州地区结核病患者结核分枝杆菌对抗结核药物的耐药情况较为严重,其耐药产生的相关危险因素与其他地区有相似之处但又有出入,因此,应根据苏州地区耐药产生的相关危险因素制定规范、个性化的诊疗方案,并加强对耐药结核分枝杆菌的防控及干预。     

耐药肺结核患者结核分枝杆菌菌型分布及耐药研究

目的 研究肺结核耐药患者结核分枝杆菌菌型分布及耐药情况。方法 收集2011年4月至2012年7月肺结核患者痰液标本,分离培养后进行菌种鉴定和药敏试验。结果 人结核分枝杆菌约占83.91%,牛结核分枝杆菌约占15.70%;患者对一线抗结核药物耐药率显著高于对二线抗结核药物耐压率,差异有统计学意义(P<0.05);一类抗结核药物单一耐药率显著高于二类抗结核药物(χ²=4.281,P<0.05)。结论 肺结核耐药患者菌型以人结核分枝杆菌最多,对一线抗结核药物的耐药率显著高于对二线抗结核药物的耐药率。     

抗结核药物的研究进展（二）

结核病仍为最具破坏性的细菌性疾病之一，发病率和死亡率都很高。结核分枝杆菌能侵入宿主免疫系统，在肺肉芽肿中持留，致使目前的抗结核药物无法杀灭菌体。近年来药物耐受以及伴有HIV感染的结核病发病率急剧增加都给结核的控制带来了很大的困难，迫切需要深入了解目前抗结核药物的作用机制及耐药机制、病菌繁殖的分子机制，以指导开发对持留菌和耐药菌更加有效的新型药物。文中介绍了近年来从现有药物中发现的具有抗结核活性的化合物，以及一些有开发潜能的抗结核药物靶点。     

艾滋病伴结核分枝杆菌感染患者对抗结核药物的耐药性分析及其对T细胞亚群表达的影响

目的:分析艾滋病伴结核分枝杆菌感染患者对抗结核药物的耐药性及其对T细胞亚群表达的影响,为临床合理用药及诊治提供参考。方法:抽取2014年1月—2018年12月间就诊的艾滋病伴结核分枝杆菌感染患者23例资料作为观察组,另抽取同期健康人30例资料作为健康组;分析其采用多参数流式细胞仪检测的两组对象外周血T淋巴细胞亚群(CD3、CD4、CD8、CD4、CD25)水平检测结果;同时,分析艾滋病伴结核分枝杆菌感染患者对抗结核药物的耐药率及其对T细胞亚群表达的影响。结果:与健康对照组比较,艾滋病伴结核分枝杆菌感染患者的T淋巴细胞(CD3、CD4、CD8、CD4、CD25)水平值均有明显差异;而23例患者抗结核药物的敏感试验中,结核分枝杆菌对异烟肼的耐药率为最高(39.13%),而其对链霉素、利福平和乙胺丁醇的耐药率分别为30.04%、26.09%和8.70%。结论:艾滋病伴结核分枝杆菌感染患者,其抗结核分枝杆菌对一线抗结核药物的耐药发生率较高,且与健康组相比较时其T淋巴细胞亚群的表达存在显著性差异。     

喹啉杂合体的抗结核活性

结核病主要由结核分枝杆菌引起，具有高发病率和死亡率等特点，是全球最具传染性的致命疾病之一。一线抗结核药物在结核患者的治疗中发挥着至关重要的作用，但结核分枝杆菌可通过内在性和获得性机制快速产生耐药性，降低了这些药物的疗效。因此，开发新型抗结核药物势在必行。喹啉类化合物可与结核分枝杆菌的多个作用靶点相结合，具有潜在的抗结核活性。喹啉母核可能是寻找新型抗结核药物的优秀骨架。特别值得一提的是，喹啉类抗结核药物贝达喹啉是继利福平之后50多年来首次问世的抗结核新药，2016年被中国国家食品药品监督管理总局批准用来联合治疗成人耐多药肺结核，这也是我国首次上市治疗耐多药肺结核新药。其中，喹啉杂合体可同时作用于结核分枝杆菌的多个结合靶点，对药敏型和耐药结核均显示出潜在的活性，引起了药物化学家的普遍关注。本文探讨了喹啉杂合体的抗结核活性及构—效关系，为进一步研究提供参考。     

Progress in the research of antituberculous drugs(I)

结核病仍为最具破坏性的细菌性疾病之一，发病率和死亡率都很高。结核分枝杆菌能侵入宿主免疫系统，在肺肉芽肿中持留，致使目前的抗结核药物无法杀灭菌体。近年来药物耐受以及伴有HIV感染的结核病发病率急剧增加都给结核的控制带来了很大的困难，迫切需要深入了解目前抗结核药物的作用机制及耐药机制、病菌繁殖的分子机制，以指导开发对持留菌和耐药菌更加有效的新型药物。文中综述了近年来通过天然物筛选、新药设计合成以及对现有抗结核药物的再修饰等途径，发现的一些有抗结核活性的化合物，以及结核杆菌分子生物学和抗结核治疗靶点的研究进展。     

靛红二聚体和杂合体的抗结核活性研究进展

结核病被认为是由单一传染源引起的最致命的疾病之一，严重威胁人类生命健康，目前已成为全球最受关注的重大公共卫生问题之一。传统的一线抗结核药物具有疗效好和毒副作用低等优点，拯救了无数人的生命。然而，随着单耐药、多耐药、耐多药和广泛耐药结核的不断涌现和广泛传播，一线抗结核药物的疗效不断下降。因此，亟须开发新型抗结核药物。不幸的是，近几十年来鲜有新型抗结核药物上市，反映出该领域的机遇与挑战。靛红类化合物具有包括抗结核在内的多种生物活性且毒副作用小，引起了药物化学家的广泛关注。其中，靛红二聚体和杂合体具有结构多样性和可作用于多个靶点等优点，对药敏型和耐药结核均显示出潜在的活性，是寻找新型抗结核药物的良好结构骨架。本文将综述2017—2022年间所研发的具有潜在抗结核活性的靛红二聚体和杂合体的最新研究进展，为进一步研究提供参考。     

306株结核分枝杆菌药敏试验结果分析

目的调查福州地区结核分枝杆菌的耐药情况,探讨该分枝杆菌耐药性的发展趋势。方法从省疾病预防控制中心门诊肺结核病人分离结核分枝杆菌,对这些结核分枝杆菌进行INH、SM、RFP、EMB等抗结核药物的敏感性测定。结果306株结核分枝杆菌的总耐药率为50.7%,多耐药率为25.16%,4种抗结核药物的耐药率由高到低分别为RFP(36.9%)、INH(31.7%)、SM(28.4%)和EMB(13.4%);耐两种药物的耐药率为INH SM(16.99%)、INH EMB(9.15%)、INH RFP(25.16%)、SM RFP(20.92%)、SM EMB(10.13%)、RFP EMB(10.78%);耐3种药物的耐药率为INH SM EMB(7.52%)、INH SM RFP(15.03%)、INH EMB RFP(7.84%)、SM EMB RFP(9.15%);耐4种药物的耐药率为6.54%;不同性别、年龄组的耐药性差异无显著性。结论调查的总耐药率和4种药物的耐药率处于较高水平,且耐药性的发生更趋向于对主要一线药物耐药和对多种药物耐药,这应引起重视。     

Type II NADH: menaquinone oxidoreductase of Mycobacterium tuberculosis

Mycobacterium tuberculosis (Mtb) remains the deadliest bacterial pathogen worldwide, causing an estimated 1.7 million deaths in 2004 among an infected population of approximately 2 billion people, according to the World Health Organization (WHO). Therapeutic options are limited to a few drugs that are becoming increasingly ineffective. Multidrug-resistant (MDR) Mtb strains are prevalent globally, fueled by inadequate patient compliance of drug intake. Recently, a high incidence of extensively drug-resistant (XDR) strains resistant to all currently used drugs was reported among patients with the human immunodeficiency virus (HIV) in KwaZulu Natal, South Africa [1]. The high mortality rate and short survival time of patients with XDR Mtb was especially alarming. The emergence of XDR mycobacteria emphasizes the urgent need for the identification of novel targets and development of new drugs. New potential drug targets exist in the Mtb respiratory chain. Certain classes of drugs have long been shown to exert significant tuberculocidal activity, such as the phenothiazines [2, 3]. Phenothiazines inhibit one of the key enzymes of the respiratory chain; type II NADH:menaquinone oxidoreductase or NDH-2 [4]. The effectiveness of this class of drugs against Mtb justifies further research into the respiratory chain, with the aim of elucidating its physiologic roles in in vitro and in vivo survival, and discovering new (sub)classes of drugs that can safely serve as inhibitors for clinical use. In this chapter, we critically review the recent advances in this field, with particular emphasis on NDH-2, and underscore the kinds of research further needed for drug development.     

Structural biology and biochemistry of cytochrome P450 systems in Mycobacterium tuberculosis

The global spread of tuberculosis (TB) has been fuelled by the development of strains of the causative bacterium (Mycobacterium tuberculosis, Mtb) that are resistant to all the leading drugs. New TB therapies are desperately needed, but recent genome sequence, genetic and protein characterization studies have helped identify novel Mtb drug targets and key biochemical pathways for strategic intervention. Of particular interest are the multiple cytochrome P450 (P450) enzymes encoded in the Mtb genome. Structural, biochemical and mechanistic studies on these systems have demonstrated their potential as antitubercular targets, as well as revealing novel aspects of P450 form and function.     

Structural Biology and Biochemistry of Cytochrome P450 Systems in Mycobacterium tuberculosis

The global spread of tuberculosis (TB) has been fuelled by the development of strains of the causative bacterium (Mycobacterium tuberculosis, Mtb) that are resistant to all the leading drugs. New TB therapies are desperately needed, but recent genome sequence, genetic and protein characterization studies have helped identify novel Mtb drug targets and key biochemical pathways for strategic intervention. Of particular interest are the multiple cytochrome P450 (P450) enzymes encoded in the Mtb genome. Structural, biochemical and mechanistic studies on these systems have demonstrated their potential as antitubercular targets, as well as revealing novel aspects of P450 form and function.     

High throughput crystallography of TB drug targets

Tuberculosis (TB) infects one-third of the world population. Despite 50 years of available drug treatments, TB continues to increase at a significant rate. The failure to control TB stems in part from the expense of delivering treatment to infected individuals and from complex treatment regimens. Incomplete treatment has fueled the emergence of multi-drug resistant (MDR) strains of Mycobacterium tuberculosis (Mtb). Reducing non-compliance by reducing the duration of chemotherapy will have a great impact on TB control. The development of new drugs that either kill persisting organisms, inhibit bacilli from entering the persistent phase, or convert the persistent bacilli into actively growing cells susceptible to our current drugs will have a positive effect. We are taking a multidisciplinary approach that will identify and characterize new drug targets that are essential for persistent Mtb. Targets are exposed to a battery of analyses including microarray experiments, bioinformatics, and genetic techniques to prioritize potential drug targets from Mtb for structural analysis. Our core structural genomics pipeline works with the individual laboratories to produce diffraction quality crystals of targeted proteins, and structural analysis will be completed by the individual laboratories. We also have capabilities for functional analysis and the virtual ligand screening to identify novel inhibitors for target validation. Our overarching goals are to increase the knowledge of Mtb pathogenesis using the TB research community to drive structural genomics, particularly related to persistence, develop a central repository for TB research reagents, and discover chemical inhibitors of drug targets for future development of lead compounds.     

抗结核新药德拉马尼作用机理和化学合成的研究进展

结核分枝杆菌感染导致的结核病仍然是全球重大公共卫生威胁。耐多药结核分枝杆菌感染所致的耐多药结核病则是2035年实现终结结核病的主要障碍之一。德拉马尼是近50年来成功研发并上市的抗结核新药之一。德拉马尼主要依据抑制枝菌酸合成的酶筛选获得,但是,其具体靶标仍然有待研究。本文综述前药德拉马尼的激活途径和基因、转录组效应、作用靶标以及化学合成,为进一步精准确定其药靶提供基础。     

Opportunities for overcoming tuberculosis: Emerging targets and their inhibitors

Tuberculosis (TB), an airborne infectious disease mainly caused by Mycobacterium tuberculosis (Mtb), remains a leading cause of human morbidity and mortality worldwide. Given the alarming rise of resistance to anti-TB drugs and latent TB infection (LTBI), new targets and novel bioactive compounds are urgently needed for the treatment of this disease. We provide an overview of the recent advances in anti-TB drug discovery, emphasizing several newly validated targets for which an inhibitor has been reported in the past five years. Our review presents several attractive directions that have potential for the development of next-generation therapies.     

FtsZ: a novel target for tuberculosis drug discovery

The emergence of multi-drug resistant Mycobacterium tuberculosis (Mtb) strains has made many of the currently available anti-TB drugs ineffective. Accordingly there is a pressing need to identify new drug targets. FtsZ, a bacterial tubulin homologue, is an essential cell division protein that polymerizes in a GTP-dependent manner, forming a highly dynamic cytokinetic ring, designated as the Z ring, at the septum site. Following recruitment of other cell division proteins, the Z ring contracts, resulting in closure of the septum and then formation of two daughter cells. Since inactivation of FtsZ or alteration of FtsZ assembly results in the inhibition of Z ring and septum formation, FtsZ is a very promising target for new antimicrobial drug development. This review describes the function and dynamic behaviors of FtsZ, its homology to tubulin, and recent development of FtsZ inhibitors as potential anti-TB agents.     

Current possibilities and unresolved issues of drug target validation in Mycobacterium tuberculosis

Introduction: Target driven drug discovery is a long and arduous task requiring a huge investment of time, energy and resources. Therefore, it is very important to select targets which provide the maximum chance of obtaining inhibitors that will be efficacious in animal models and finally in tuberculosis (TB) patients. Areas covered: The article discusses the necessity for new targets in Mycobacterium tuberculosis (Mtb) drug discovery and how the functional redundancy of putative targets in Mtb adds a new dimension to the complexity of validation. The article also reviews survival kinetics using conditional knockout (KO) or knockdown (KD) strains and discusses how this has provided crucial information on target vulnerability. Furthermore, the article also comments on how the chemical validation of new targets using specific inhibitors has greatly supplemented the genetic validation efforts. Expert opinion: Because of complexity of pathogenesis of TB, the putative drug targets need to be validated under multiple physiological conditions. Target protein depletion can mimic chemical inhibition and, therefore, will be a valuable tool in predicting the vulnerability of a target. Conditional KO or KD makes it possible to study the phenotypes of Mtb strains under a variety of physiological states. The phenotype of these strains should also be tested in animal models which mimic human TB more closely. Finally, inhibitors with confirmed mode of action can be important tools for validating Mtb drug targets.     

New anti-tuberculosis drugs in clinical trials with novel mechanisms of action

Tuberculosis is a major health problem worldwide, with approximately 1.7 million people dying annually from the disease. The long current drug regimen, the emergence of drug resistant strains and HIV co-infection have resulted in a resurgence in research efforts to address the urgent need for new anti-tuberculosis drugs. A number of new potential anti-tuberculosis drug candidates with novel modes of action have entered clinical trials in recent years. These agents are most likely to be effective against resistant strains. We provide a concise review of their structure-activity relationships, in vitro and in vivo activity, pharmacokinetics, mechanism of action and combination regimens.