Search results for "Mycobacterium"
showing 10 items of 212 documents
The burden and epidemiology of community-acquired central nervous system infections: a multinational study
2017
Ghaydaa, Shehata/0000-0002-3631-893X; Radic, Ljiljana Betica/0000-0002-8778-106X; Silva-Pinto, Andre/0000-0002-2077-3356; Cascio, Antonio/0000-0002-1992-1796; Bossi, Paolo/0000-0003-0135-0224; Stebel, Roman/0000-0001-6922-4465; Namani, Sadie/0000-0002-2411-8623; Chan, Phillip/0000-0002-4071-4409; Hargreaves, Sally/0000-0003-2974-4348; Artuk, Cumhur/0000-0003-0827-990X; Harxhi, Arjan/0000-0001-8518-7377; Larsen, Lykke/0000-0002-4113-4182; Uysal, Serhat/0000-0002-4294-5999 WOS: 000407582200010 PubMed: 28397100 Risk assessment of central nervous system (CNS) infection patients is of key importance in predicting likely pathogens. However, data are lacking on the epidemiology globally. We perfor…
Subtle genotypic changes can be observed soon after diagnosis in Mycobacterium tuberculosis infection.
2016
Clonal variants of Mycobacterium tuberculosis (MTB) coexist in specific patients, although the dynamics of their emergence is unknown. We used MIRU-VNTR to detect microevolution leading to variants of MTB in 3 out of 19 patients (15%) soon after diagnosis (61-85 days). Most harbored SNPs and for some of them a potential functional role was suggested. Microevolution in tuberculosis seems to occur sooner and more often than expected and could affect tracking of transmission.
A New Phylogenetic Framework for the Animal-adaptedMycobacterium tuberculosisComplex
2018
Tuberculosis (TB) affects humans and other animals and is caused by bacteria from the Mycobacterium tuberculosis complex (MTBC). Previous studies have shown that there are at least nine members of the MTBC infecting animals other than humans; these have also been referred to as ecotypes. However, the ecology and the evolution of these animal-adapted MTBC ecotypes are poorly understood. Here we screened 12,886 publicly available MTBC genomes and newly sequenced 17 animal-adapted MTBC strains, gathering a total of 529 genomes of animal-adapted MTBC strains. Phylogenomic and comparative analyses confirm that the animal-adapted MTBC members are paraphyletic with some members more closely relate…
Mycobacterium avium subsp. paratuberculosis (Map) Fatty Acids Profile Is Strain-Dependent and Changes Upon Host Macrophages Infection
2017
Johne´s disease is a chronic granulomatous enteritis of ruminants caused by the intracellular bacterium Mycobacterium avium subsp. paratuberculosis (Map). We previously demonstrated that Map isolates from sheep persisted within host macrophages in lower CFUs than cattle isolates after 7 days of infection. In the current study, we hypothesize that these phenotypic differences between Map isolates may be driven be the fatty acids (FAs) present on the phosphadidyl-1-myo-inositol mannosides of the Map cell wall that mediate recognition by the mannose receptors of host macrophages. FAs modifications may influence Map´s envelope fluidity ultimately affecting pathogenicity. To test this hypothesis…
Low sensitivity of the MPT64 identification test to detect lineage 5 of the Mycobacterium tuberculosis complex
2018
Abstract: Purpose. Differentiation of the Mycobacterium tuberculosis complex (MTBc) from non-tuberculous mycobacteria (NTM) is important for tuberculosis diagnosis and is a prerequisite for reliable phenotypic drug-resistance testing. We evaluated the performance of the rapid MPT64 antigen identification test for the detection of Mycobacterium africanum lineage 5 (MAF L5). Methodology. Smear-positive tuberculosis patients' sputa were included prospectively. Culture was performed on Lowenstein-Jensen medium and, when positive, the MPT64 test and the classical para-nitro benzoic acid susceptibility and heat-labile catalase (PNB/catalase) identification tests were performed. The MPT64 test was…
Large genomics datasets shed light on the evolution of the Mycobacterium tuberculosis complex
2019
Review: 5 páginas, 1 figura
Are moxifloxacin and levofloxacin equally effective to treat XDR tuberculosis?
2017
International audience; Background: Moxifloxacin retains partial activity against some fluoroquinolone-resistant mutants of Mycobacterium tuberculosis. Levofloxacin is presumed to be as active as moxifloxacin against drug-susceptible tuberculosis and to have a better safety profile.Objectives: To compare the in vivo activity of levofloxacin and moxifloxacin against M. tuberculosis strains with various levels of fluoroquinolone resistance.Methods: BALB/c mice were intravenously infected with 106M. tuberculosis H37Rv and three isogenic mutants: GyrA A90V, GyrB E540A and GyrB A543V. Treatment with 50 or 100 mg/kg levofloxacin and 60 or 66 mg/kg moxifloxacin was given orally every 6 h, for 4 we…
In-Depth Characterization and Functional Analysis of Clonal Variants in a Mycobacterium tuberculosis Strain Prone to Microevolution
2017
The role of clonal complexity has gradually been accepted in infection by Mycobacterium tuberculosis (MTB), although analyses of this issue are limited. We performed an in-depth study of a case of recurrent MTB infection by integrating genotyping, whole genome sequencing, analysis of gene expression and infectivity in in vitro and in vivo models. Four different clonal variants were identified from independent intrapatient evolutionary branches. One of the single-nucleotide polymorphisms in the variants mapped in mce3R, which encodes a repressor of an operon involved in virulence, and affected expression of the operon. Competitive in vivo and in vitro co-infection assays revealed higher infe…
Mycobacterium tuberculosis Acquires Limited Genetic Diversity in Prolonged Infections, Reactivations and Transmissions Involving Multiple Hosts
2018
9 páginas, 5 figuras y material suplementario en: https://www.frontiersin.org/articles/10.3389/fmicb.2017.02661/full#supplementary-material
Field performance of the Abbott RealTime MTB assay for the diagnosis of extrapulmonary tuberculosis in a low-prevalence setting
2020
Introduction: The sensitivities of conventional mycobacterial culture in solid or liquid media and acid-fast bacilli (AFB) smear microscopy for Mycobacterium tuberculosis complex (MTBC) detection in extrapulmonary specimens are suboptimal. We evaluated the field performance of the Abbott RealTime MTB assay for the diagnosis of extrapulmonary tuberculosis in a low-prevalence setting. Methods: The total number of extrapulmonary specimens with mycobacterial culture and PCR results was 566: sterile fluids (n = 278), non-sterile fluids (n = 147), lymph node material (n = 69) tissue biopsies (n = 63), and abscess aspirates (n = 9). A composite standard consisting of mycobacterial culture results,…