Publications by authors named "Toidi Adekambi"

Antigen-specific CD4 T cell responses to (Mtb) infection are important for host defense against tuberculosis (TB). However, Mtb-specific IFN-γ-producing T cells do not distinguish active tuberculosis (ATB) patients from individuals with asymptomatic latent Mtb infection (LTBI). We reasoned that the immune phenotype of Mtb-specific IFN-γCD4 T cells could provide an indirect gauge of Mtb antigen load within individuals.

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continues to cause devastating levels of mortality due to tuberculosis (TB). The failure to control TB stems from an incomplete understanding of the highly specialized strategies that utilizes to modulate host immunity and thereby persist in host lungs. Here, we show that induced the expression of indoleamine 2,3-dioxygenase (IDO), an enzyme involved in tryptophan catabolism, in macrophages and in the lungs of animals (mice and macaque) with active disease.

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TheMycobacterium abscessus complex is a group of rapidly growing, multiresistant mycobacteria previously divided into three species. Proposal for the union of Mycobacterium bolletii and Mycobacterium massiliense into one subspecies, so-called M. abscessus subsp.

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Neutrophils are increasingly associated with tuberculosis (TB) disease. Neutrophil extracellular traps (NETs), which are released by neutrophils as a host antimicrobial defense mechanism, are also associated with tissue damage. However, a link between NET levels and TB disease has not been studied.

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Tuberculosis (TB) is a global pandaemic, partially due to the failure of vaccination approaches. Novel anti-TB vaccines are therefore urgently required. Here we show that aerosol immunization of macaques with the Mtb mutant in SigH (MtbΔsigH) results in significant recruitment of inducible bronchus-associated lymphoid tissue (iBALT) as well as CD4(+) and CD8(+) T cells expressing activation and proliferation markers to the lungs.

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Background: The identification and treatment of individuals with tuberculosis (TB) is a global public health priority. Accurate diagnosis of pulmonary active TB (ATB) disease remains challenging and relies on extensive medical evaluation and detection of Mycobacterium tuberculosis (Mtb) in the patient's sputum. Further, the response to treatment is monitored by sputum culture conversion, which takes several weeks for results.

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Human immunodeficiency virus (HIV)-infected individuals with latent Mycobacterium tuberculosis infection have substantially higher rates of progression to active tuberculosis than HIV-uninfected individuals with latent tuberculosis. To explore HIV-induced deficits in M. tuberculosis-specific CD8+ T-cell functions, we compared interferon γ production, degranulation, and proliferation of CD8+ T cells in response to M.

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Mycobacterium tuberculosis is a highly successful human pathogen that primarily resides in host phagocytes, such as macrophages and dendritic cells (DCs), and interferes with their functions. Although multiple strategies used by M. tuberculosis to modulate macrophage responses have been discovered, interactions between M.

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Two billion people worldwide are estimated to be latently infected with Mycobacterium tuberculosis (Mtb) and are at risk for developing active tuberculosis since Mtb can reactivate to cause TB disease in immune-compromised hosts. Individuals with latent Mtb infection (LTBI) and BCG-vaccinated individuals who are uninfected with Mtb, harbor antigen-specific memory CD4(+) T cells. However, the differences between long-lived memory CD4(+) T cells induced by latent Mtb infection (LTBI) versus BCG vaccination are unclear.

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Comparative genomic sequencing is shedding new light on bacterial identification, taxonomy and phylogeny. An in silico assessment of a core gene set necessary for cellular functioning was made to determine a consensus set of genes that would be useful for the identification, taxonomy and phylogeny of the species belonging to the subclass Actinobacteridae which contained two orders Actinomycetales and Bifidobacteriales. The subclass Actinobacteridae comprised about 85% of the actinobacteria families.

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The omission of the name 'Mycobacterium paraffinicum' from the Approved Lists of Bacterial Names was due to phenotypic confusion surrounding a close relationship with Mycobacterium scrofulaceum. Correspondingly, 'M. paraffinicum' strains grew slowly in > 7 days, stained acid-alcohol-fast and produced yellow-pigmented, smooth, waxy colonies in the dark at an optimal temperature of 35°C.

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We isolated Mycobacterium phocaicum, an emerging non-tuberculous species rarely identified in the respiratory tract and blood of patients, from the therapy pool water. Identification, confirmed by 16S rDNA and rpoB sequencing and phylogenetic analyses, disclosed a genotype 4. M.

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Contrary to other species in the Mycobacterium chelonae-abscessus complex, we reidentified M. bolletii strains isolated from 4 respiratory patients and found these strains to be uniformly resistant to clarithromycin. No mutations previously associated with macrolide resistance in bacteria were detected in either the 23S rDNA or the genes encoding riboproteins L4 and L22.

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The rpoB gene, encoding the beta-subunit of RNA polymerase, has emerged as a core gene candidate for phylogenetic analyses and identification of bacteria, especially when studying closely related isolates. Together with the 16S rRNA gene, rpoB has helped to delineate new bacterial species and refine bacterial community analysis, as well as enabling the monitoring of rifampicin resistance-conferring mutations. Sequencing of rpoB enables efficient estimation of bacterial G+C% content, DNA-DNA hybridization value and average nucleotide identity (percentage of the total genomic sequence shared between two strains) when taxonomic relationships have been firmly established.

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The Mycobacterium avium complex (MAC) comprises slowly growing mycobacteria responsible for opportunistic infections and zoonoses. The ability to speciate MAC isolates in the clinical microbiology laboratory is critical for determining the organism implicated in clinical disease and for epidemiological investigation of the source of infection. Investigation of a 711 bp variable fragment of rpoB flanked by the Myco-F/Myco-R primers found a 0.

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DNA-DNA hybridization (DDH), the gold standard for bacterial species delineation, is a laborious method and the alternative, average nucleotide identity (ANI), a genomic sequence-derived parameter, is not applicable to non-sequenced species. A universal cut-off value to delineate bacterial species does not exist, yet a DDH value <70 % and ANI <95+/-0.5 % have proved useful in selected examples.

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Two bacterial organisms, 50640T and 823, were isolated from fresh water in Marseilles, France, and were further identified as members of the genus Yersinia on the basis of their phenotypic characteristics and 16S rRNA gene sequencing. Their unique phenotypic profile differed from that of closely related species of Yersinia bercovieri and Yersinia mollaretii by exhibiting positive indole and inositol tests, and from that of Yersinia frederiksenii by lacking the ability to ferment l-rhamnose. A polyphasic approach, including almost complete 16S rRNA gene sequencing (1461 bp) and partial sequencing of hsp60 (683 bp), gyrB (662 bp), sodA (624 bp) and rpoB (1049 bp) showed that isolates 50640T and 823 exhibited 98.

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Between March and May 2006, a Texas hospital identified five Mycobacterium mucogenicum bloodstream infections among hospitalized oncology patients using fluorescence high-performance liquid chromatography analysis of mycolic acids. Isolates from blood cultures were compared to 16 isolates from environmental sites or water associated with this ward. These isolates were further characterized by hsp65, 16S rRNA, and rpoB gene sequencing, hsp65 PCR restriction analysis, and molecular typing methods, including repetitive element PCR, random amplified polymorphic DNA PCR, and pulsed-field gel electrophoresis (PFGE) of large restriction fragments.

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Three identical isolates of new rapidly growing mycobacteria (RGM) were recovered from the bronchial aspirate and sputum from a 49-year-old woman presenting with lung lesions. The case met the American Thoracic Society criteria for the diagnosis of nontuberculous mycobacterial infection. The three isolates grew in 3 days at 24 to 42 degrees C.

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Free-living amoebae in water are hosts to many bacterial species living in such an environment. Such an association enables bacteria to select virulence factors and survive in adverse conditions. Waterborne mycobacteria (WBM) are important sources of community- and hospital-acquired outbreaks of nontuberculosis mycobacterial infections.

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A nonpigmented rapidly growing mycobacterium was isolated from wound liquid outflow, bone tissue biopsy, and excised skin tissue from a 31-year-old woman who suffered an accidental open right tibia fracture and prolonged stay in a river. The three isolates grew in 3 days at 24 to 37 degrees C. 16S rRNA sequence analyses over 1,483 bp showed that they were identical and shared 99.

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Neurological infections due to rapidly growing mycobacteria (RGM) have rarely been reported. We recently investigated two unrelated immunocompetent patients, one with community-acquired lymphocytic meningitis and the other with cerebral thrombophlebitis. Mycobacterium mucogenicum was isolated in pure culture and detected by PCR sequencing of cerebrospinal fluid samples.

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