结核分枝杆菌热休克蛋白65与汉坦病毒G2糖蛋白融合基因真核表达载体的构建与表达

目的 构建以结核分枝杆菌热休克蛋白65（HSP65）和汉坦病毒G2糖蛋白重组融合基因为基础的真核表达载体。为进一步研究其在结核病和出血热防治中的作用奠定基础。方法 采用聚合酶链反应从结核分枝杆菌H37Rv株基因中．扩增出HSP65的编码基因，从T-H8205G2质粒扩增出G2糖蛋白的编码基因．经相应限制性核酸内切酶消化后．插入真核表达载体pcDNA3．1／His，并将此重组质粒通过脂质体介导转染NIH3T3细胞．用SDS-PAGE、免疫组织化学及免疫荧光方法分别测定表达产物的相对分子量及特异性。结果 获得正向插入的pcDNA3.1/ His-HSP65-G2重组表达质粒，表达产物的相对分子量为105kD．与理论预期大小一致．并且可与汉坦病毒H8205株的腹水抗体和HSP65单抗起特异反应。表明构建的pcDNA3．1／His-HSP65-G2能在哺乳动物细胞中表达并具有抗原性。结论 编码HSP65和G2抗原基因的重组基因的真核表达载体构建成功。     

耐多药结核分枝杆菌三种基因的快速检测

目的 :探讨耐多药结核分枝杆菌耐药基因突变与耐药性的关系。方法 :采用 PCR和 PCR- DS技术对 5 7例耐多药结核临床分离株进行 kat G、rpo B和 emb B基因检测和序列分析。结果 :耐 INH(kat G)、RFP(rpo B)、EMB(emb B)基因突变率分别为 6 3.8%、90 .7%、37.1% ,其中同时耐 INH(kat G)和 RFP(rpo B)基因突变率为 5 4 .1% ,同时耐三种药的基因突变率为 6 5 .6 %。结论 :PCR- DS法对耐两种或两种以上药物的结核检出率较高 ,与传统药敏试验互相弥补 ,对临床用药有指导意义。     

Endotracheal involvement from atypical mycobacterium causing respiratory difficulty: Case report and literature review

Atypical mycobacterium infections often present as cervicofacial lymphadenitis in pediatric patients. Endotracheal involvement, however, is rare, and has not been previously described with imaging and photographs.An infant with natural killer T-cell deficiency was admitted with cough, rhinorrhea, and cervical lymphadenopathy. Laryngotracheobronchitis-type symptoms persisted and imaging revealed an intraluminal abnormality of the trachea. Endoscopy confirmed a mediastinal lymph node with intrusion into the tracheal lumen. Intraluminal biopsy was deferred due to concerns of airway loss. Biopsy of the associated cervical lymph node confirmed Mycobacterium avium-intracellulare infection. The patient was managed with antibiotics and steroids with clinical resolution of his respiratory symptoms.     

Mycobacterium abscessus Complex – a Particular Challenge in the Setting of Lung Transplantation

Mycobacterium abscessus complex is an emerging pathogen in lung transplant candidates and recipients. M. abscessus complex is widespread in the environment and can cause pulmonary, skin and soft tissue, and disseminated infection, particularly in lung transplant recipients. It is innately resistant to many antibiotics making it difficult to treat. Herein we describe the epidemiology, clinical manifestations, diagnosis and treatment of M. abscessus with an emphasis on lung transplant candidates and recipients. We also outline the areas where data are lacking and the areas where further research is urgently needed.     

Drastically Progressive Ethambutol-induced Optic Neuropathy after Withdrawal of Ethambutol: A Case Report and Literature Review

Ethambutol-induced optic neuropathy (EON) is a well-known complication, although low-dose ethambutol seldom causes EON. An 85-year-old man with non-tuberculous mycobacterial lung disease was taking antibiotics, including low-dose ethambutol. On day 85 of treatment, the diagnosis of EON was made. Despite prior discontinuation, his best corrected visual acuity drastically deteriorated from 20/17 (right eye) and 20/20 (left eye) to 20/330 (right eye) and 20/1,000 (left eye) within 3 weeks, and this symptom did not resolve. To our knowledge, there have been no reported cases with drastically progressing and irreversible EON even after the withdrawal of low-dose and short-term ethambutol.     

结核分枝杆菌的培养分离及耐药性分析

目的探讨结核杆菌分离培养及其耐药性。方法收集2006年1-11月本院就诊的疑似结核患者的标本,采用美国BD公司BACTEC MGIT960全自动分枝杆菌快速鉴定仪培养鉴定及药敏试验。结果从654份送检标本分离到结核分枝杆菌361株,结核杆菌耐药情况为链霉素29.4%、利福平17.5%、异烟肼32.1%、乙胺丁醇11.9%,多耐药结核杆菌为24.7%（89/361）。结论结核杆菌耐药情况非常严峻,必须加大力度狠抓结核病防治工作,加强合理用药,遏止多耐药结核杆菌的蔓延。     

Functional heterogeneity of colony-stimulating factor-induced human monocyte-derived macrophages

Objectives:   Macrophages (Mφs) have various functions and play a critical role in host defense and the maintenance of homeostasis. Mφs exist in every tissue in the body, but Mφs from different tissues exhibit a wide range of phenotypes with regard to their morphology, cell surface antigen expression and function, and are called by different names. However, the precise mechanism of the generation of macrophage heterogeneity is not known. In the present study, the authors examined the functional heterogeneity of Mφs generated from human monocytes under the influence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and macrophage-CSF (M-CSF).
Methodology:   CD14 positive human monocytes (Mos) were incubated with M-CSF and GM-CSF for 6–7 days to stimulate the generation of M-CSF-induced monocyte-derived Mφs (M-Mφs) and GM-CSF-induced monocyte-derived Mφs (GM-Mφs), respectively. The expression of cell surface antigens and several functions such as antigen presenting cell activity, susceptibility to oxidant stress, and the susceptibility to HIV-1 and mycobacterium tuberculosis infection were examined.
Results:   GM-Mφs and M-Mφs are distinct in their morphology, cell surface antigen expression, and functions examined. The phenotype of GM-Mφs closely resembles that of human Alveolar-Mφs (A-Mφs), indicating that CSF-induced human monocyte-derived Mφs are useful to clarify the molecular mechanism of heterogeneity of human Mφs, and GM-Mφs will become a model of human A-Mφs.     

Clinical and demographic study of non-tuberculous mycobacterial ocular infections in South India

PurposeTo describe demographics, risk factors, antibiotic susceptibility, management and outcomes of ocular infections caused by non-tuberculous mycobacteria (NTM).MethodsA retrospective review of medical case records and microbiology records of patients with ocular infections that were culture positive for non-tuberculous Mycobacteria from January 2014 to December 2018 was done. Antibiotic susceptibility profile was done based on the CLSI guidelines. Laboratory diagnosis for the NTM Species was done by conventional microbiological methods. The species identification was done for stored isolated utilizing polymerase chain reaction targeting 16S rDNA and rpoB gene, followed by DNA sequencing and phylogenetic analysis.ResultsTwenty patients with NTM ocular infections were identified during the study period. A majority of cases presented as 12 infectious keratitis (60%) and three suture-related corneal infiltrates (15%). Common risk factors were history of trauma in 9 (45%) patients and history of ocular surgery in 5 (25%) patients. Patients were treated with combination of amikacin and flouroquinolones/chloramphenicol (70%) and surgical interventions were performed in 25% cases. Only twelve isolates were stored and ten isolates were identified as the M. abscessus subsp. abscessus and two isolates as M. abscessus subsp. massiliense by sequencing and phylogenetic analysis. Majority of the NTM were sensitive to amikacin (75%) followed by moxifloxacin, ciprofloxacin, cephotaxime and tobramycin (35%).ConclusionHigh degree of clinical suspicion, multidrug antibiotic therapy and timely surgical intervention in patients with NTM infections, are advised for better clinical outcomes. Prior ocular trauma, prior ocular surgery and presence of biomaterials were the major predisposing factors. Earlier surgical intervention in cases where abscesses or biomaterials are involved, is necessary for rapid recovery.     

Identification and pathogenicity analysis of a novel non-tuberculous mycobacterium clinical isolate with nine-antibiotic resistance

With mycobacteriosis increasing, the study of non-tuberculous mycobacteria is imperative for clinical therapy and management. Nontuberculous mycobacteria are naturally resistant to most anti-tuberculosis drugs. Accordingly, it is important to decipher the biology of the novel non-tuberculous mycobacteria through complete genomic analysis of novel pathogenic mycobacteria. We describe Mycobacterium sinense JDM601, a novel, slow-growing mycobacterium of the Mycobacterium terrae complex resistant to nine antibiotics, by clinical presentation, cultural and biochemical characteristics, minimal inhibitory concentrations, and genome-sequencing analysis. JDM601 is closest to Mycobacterium nonchromogenicum according to mycolic acid composition, but closest to Mycobacterium algericum sp. nov according to 16S rDNA. JDM601 is resistant to isoniazid, streptomycin, rifampin, euteropas, protionamide, capromycin, ciprofloxacin, amikacin and levofloxacin but not ethambutol. The clinical information, mycolic acid composition, and virulence genes indicate that JDM601 is an opportunistic pathogen.     

γ-干扰素体外释放试验在结核病诊断中的价值

目的探讨γ-干扰素(γ-IFN)体外释放试验(IGRA)对诊断结核病的临床价值。方法 479例结核病患者纳入结核病组,42例体检健康者纳入对照组。两组被试均行IGRA、蛋白芯片法检测,采用抗酸染色(AFB)检测结核病患者痰液中的抗酸杆菌。比较IGRA与蛋白芯片法对结核病的诊断效能及在肺结核与肺外结核中的检测效果,并比较IGRA对AFB阳性和阴性的肺结核和肺外结核患者的检测效果。结果IGRA和结核分枝杆菌蛋白芯片法敏感度分别为89.56%(429/479)和76.20%(365/479),特异度分别为100.00%(42/42)和88.10(37/42),准确率分别为90.40%(471/521)和77.16%(402/521)。418例肺结核患者中AFB阳性127例,AFB阴性者291例,其中AFB阳性肺结核患者中IGRA阳性率为93.70%(119/127),AFB阴性肺结核患者阳性率为88.66%(258/291);肺外结核61例患者AFB均阴性,IGRA和结核分枝杆菌蛋白芯片阳性率分别为85.25%(52/61)和68.85%(42/61)。结论 IGRA与结核分枝杆菌蛋白芯片法相比,对结核病诊断有较高的敏感度与特异度,尤其是对AFB阴性的结核病有较高的检出率,值得临床推广应用。