Publications by authors named "Paulo Redner"

Species belonging to the complex (MKC) are frequently isolated from humans and the environment and can cause serious diseases. The most common MKC infections are caused by the species (), leading to tuberculosis-like disease. However, a broad spectrum of virulence, antimicrobial resistance and pathogenicity of these non-tuberculous mycobacteria (NTM) are observed across the MKC.

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Article Synopsis
  • - The study focused on analyzing the genetic diversity of Mycobacterium tuberculosis (Mtb) isolates from drug-resistant tuberculosis patients in Brazil, finding a high prevalence of multidrug-resistant cases at 54.8% and pre-extensively drug-resistant cases at 9.2%.
  • - Researchers utilized whole-genome sequencing (WGS) to scrutinize 298 Mtb isolates, identifying the most common sub-lineage as 4.3 and uncovering 20 new mutations linked to drug resistance, with significant ongoing transmission among patients noted through genomic clustering.
  • - The in-house WGS pipeline outperformed online tools in predicting drug resistance, revealing key associations between certain genotypes and severe disease outcomes, which enhances the understanding of
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We present the pathology of monkeys naturally infected with Mycobacterium tuberculosis complex from five different colonies in Rio de Janeiro, Brazil. On the basis of gross and histopathological findings, the lesions were classified into chronic-active, extrapulmonary, early-activation or latent-reactivation stages. Typical granulomatous pneumonia was seen in 46.

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Twenty-one pulmonary sputum samples from nine Brazilian patients were analyzed by the PRA-hsp65 method for identification of Mycobacterium species and the results were compared by sequencing. We reported a mutation at the position 381, that generates a suppression cutting site in the BstEII enzyme, thus leading to a new PRA-hsp65 pattern for M. asiaticum identification.

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Objectives: Mycobacterium kansasii (M. kansasii) pulmonary infection can cause disease with clinical and radiological features similar to tuberculosis. Failure to treat M.

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Tuberculosis patients taking second line drugs such as ethionamide (ETH) have often experienced previous treatment failure and usually have a complex history of disease and treatment that can span decades. Mutations in the ETH activating enzyme, EthA, confer resistance through undescribed mechanisms. To explore the impact of EthA mutations on ETH resistance, data from a total of 160 ETH isolates was analysed.

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Mycobacterium kansasii is an opportunistic pathogen and one of the most commonly encountered species in individuals with lung disease. We here report the complete genome sequence of 12 clinical isolates of M. kansasii from patients with pulmonary disease in Brazil.

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Drug-resistant tuberculosis (DR-TB) poses a serious threat to tuberculosis (TB) control in Brazil and worldwide. The current study investigated factors associated with loss to follow-up and death in the course of treatment for DR-TB in a tertiary reference center in the city of Rio de Janeiro, Brazil. This was a retrospective cohort study of cases reported to the Information System on Special Treatments for Tuberculosis (SITETB) from January 1, 2012, to December 31, 2013.

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Tuberculosis is a major public health concern, and diagnostic strategies applied to animal populations are scarce. As part of ongoing efforts to control tuberculosis dissemination at our animal facility, two non-human primates (NHP, Saimiri sciureus) presenting cutaneous lesions were examined for mycobacterial infection. Both animals tested positive for acid-fast bacilli and Mycobacterium tuberculosis using a molecular assay (IS6110 PCR).

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In this study we describe the first isolation of Mycobacterium triplex in Latin America. This species causes infections in humans, with very few reports from around the world. We isolated two sputum specimens of a patient with a 6-year history of human immunodeficiency and tuberculosis treatment failure.

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Three isolates of a slow-growing, non-chromogenic mycobacterium were grown from three sputum samples of a patient from the north-eastern Ceará state in Brazil. Identification at species level could not be obtained with PCR restriction analysis of the hsp65 gene. In order to characterize the isolates we carried out phenotypic and genotypic tests.

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In this article, the first isolation of Mycobacterium kyorinense specimens in Brazil is described. M. kyorinense is a recently identified species, with a few strains reported only in Japan.

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It is widely accepted that tumor necrosis factor alpha (TNF-α) plays a critical role in the development of tissue and nerve damage in leprosy and during the reactional episodes of acute inflammation. Thalidomide (N-α-phthalimidoglutarimide), a drug used to treat leprosy reaction, modulates immune response, inhibits inflammation and NF-κB activity. Here we investigated whether thalidomide inhibits NF-κB activation induced by Mycobacterium leprae, p38 and ERK1/2 MAPK activation.

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The aqueous fraction of the ethanolic extract of the plant CISSAMPELOS SYMPODIALIS (Menispermaceae) was previously described to inhibit B cell function. The alkaloid warifteine is the major component of this extract. In the present study we investigated the effect of warifteine on B lymphocyte function and characterized its mechanism of action.

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We have showed that a phospholipase A(2) isolated from Lachesis muta snake venom, denoted LM-PLA(2)-I, had some biological effects. Here, we examined its effects on lymphocytes. Pre-incubation of human peripheral blood lymphocytes with LM-PLA(2)-I plus phosphatidylcholine (PC) stimulated the natural killer (NK) activity.

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Mycobacterium leprae, the causative agent of leprosy, invades peripheral nerve Schwann cells, resulting in deformities associated with this disease. NF-kappaB is an important transcription factor involved in the regulation of host immune antimicrobial responses. We aimed in this work to investigate NF-kappaB signaling pathways in the human ST88-14 Schwannoma cell line infected with M.

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