Publications by authors named "Pedro E A Silva"

Despite the many advances in drug research, natural products are still being explored as a promising source for discovering new bioactive compounds to treat global diseases such as tuberculosis. However, there is a lack of studies and information about coastal natural products, which thrive in the transitional environment between two different ecosystems and produce unique secondary metabolites. Mangroves, estuaries, and mudflats make up areas for coastal species and have shown promising results in antituberculosis research, some of them are present in hotspot areas.

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The Red Queen Hypothesis (RQH), derived from Lewis Carroll's "Through the Looking-Glass", postulates that organisms must continually adapt in response to each other to maintain relative fitness. Within the context of host-pathogen interactions, the RQH implies an evolutionary arms race, wherein viruses evolve to exploit hosts and hosts evolve to resist viral invasion. This study delves into the dynamics of the RQH in the context of virus-cell interactions, specifically focusing on virus receptors and cell receptors.

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Zika virus (ZIKV) and dengue virus (DENV) share a lot of similarities being both phylogenetically closely related, share the same insect vector passage for reaching the host, affinity for the same carbohydrate receptor domains (CRDs), indicating feasible competition between them on the natural field. Here, we prospected interactions of both envelope proteins with a DC-SIGN, a transmembrane c-type lectine receptor with the most implicated CRD with the Flavivirus infection presents on dendritic cells involved in viruses replication processes into the host, and among rares CRD receptors susceptible to interacting with a broad of subtypes of DENV. Protein-protein docking procedures produced structures for molecular dynamics experiments, suggesting the most energetically favorable complex.

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Introduction: Horse racing is a major sport practiced worldwide. The environment to which horses are exposed during race meetings can influence their behavior. However, to the best of our knowledge, a method for assessing a horse's response to its surroundings during the pre- and post-race periods has not yet been reported.

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Tuberculosis (TB) is a serious infectious disease, and its control is considered a challenge, especially among vulnerable populations such as prisoners. The occurrence of TB in prisons is an alarming public health problem in many countries. This integrative review aims to describe the epidemiology of TB and control strategies for this disease in countries with the largest prison populations.

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Tuberculosis (TB) has a high incidence in several countries and is even more severe in prisoners. We evaluated the completeness of prisoners TB notifications in the Notifiable Disease Information System (SINAN) carried out by prison primary care teams (eAPP) or by other health facilities in the state of Rio Grande do Sul (RS). This descriptive cross-sectional study used prisoners data notifications in the SINAN TB by the eAPP or other health facilities from January 2014 to November 2018.

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Background: Tuberculosis is a worldwide public health problem and is more prevalent in specific populations, such as prisoners. The aim of this study was to analyze the epidemiological and operational indicators of tuberculosis in prisoners in a southern region of Brazil.

Methods: This was a descriptive, observational study, utilizing secondary data from the Notifiable Diseases Information System on tuberculosis cases diagnosed in prisoners in the state of Rio Grande do Sul, southern Brazil, from 2014 to 2018.

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Background: Tuberculosis (TB) remains a serious public health problem, with approximately 10 million new cases reported annually. Knowledge about the quantitative evolution of theses and dissertations (T&Ds) examining human TB in Brazil can contribute to generating strategic planning for training professionals in this field and disease control. Therefore, this study highlights the role of T&Ds on TB in national scientific disclosures.

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Background: Non-tuberculous mycobacteria (NTMs) cause diseases known as mycobacteriosis and are an important cause of morbidity and mortality. The diagnosis of pulmonary disease caused by NTM is hampered by its clinical similarity with tuberculosis (TB) and by the lack of an accurate and rapid laboratory diagnosis.

Objectives: Detect DNA from NTMs directly from lung samples using real-time polymerase chain reaction (qPCR) for amplification of 16S rRNA.

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Genomic-based surveillance on the occurrence of drug resistance and its transmission dynamics has emerged as a powerful tool for the control of tuberculosis (TB). A whole-genome sequencing approach, phenotypic testing and clinical-epidemiological investigation were used to undertake a retrospective population-based study on drug-resistant (DR)-TB in Rio Grande do Sul, the largest state in Southern Brazil. The analysis included 305 resistant Mycobacterium tuberculosis strains sampled statewide from 2011 to 2014, and covered 75.

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Tuberculosis (TB) is one of the top 10 causes of death in humans worldwide. The most important causative agents of TB are bacteria from the Mycobacterium tuberculosis complex (MTC), although nontuberculous mycobacteria (NTM) can also cause similar infections. The ability to identify and differentiate MTC isolates from NTM is important for the selection of the correct antimicrobial therapy.

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The continuous emergence of resistant Mycobacterium tuberculosis keeps tuberculosis (TB) treatment options still insufficient, and new therapeutic alternatives are urgently needed. Considering the antimycobacterial activity of phenazine derivatives previously reported by our research group, we aimed to explore possible applications to circumvent the resistance in M. tuberculosis.

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Studies displaying the combination of mefloquine (MFL) with anti-tuberculosis (TB) substances are limited in the literature. In this work, the effect of MFL-association with two first-line anti-TB drugs and six fluoroquinolones was evaluated against Mycobacterium tuberculosis drug resistant strains. MFL showed synergistic interaction with isoniazid, pyrazinamide, and several fluoroquinolones, reaching fractional inhibitory concentration indexes (FICIs) ranging from 0.

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Background: Lipid nanocarriers have been widely tested as drug delivery systems to treat diseases due to their bioavailability, controlled release, and low toxicity. For the pulmonary route, the Food and Drug Administration favors the use of substances generally recognized as safe, as well as biodegradable and biocompatible to minimize the possibility of toxicity. Tuberculosis (TB) remains a public health threat worldwide, mainly due to the long treatment duration and adverse effects.

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Article Synopsis
  • * A study involving 228 prisoners in Brazil aimed to analyze TB's transmission dynamics and antimicrobial resistance, finding that 15.4% were diagnosed with TB and a small percentage had TB/HIV co-infection.
  • * The results highlighted low rates of other co-infections and some instances of antimicrobial resistance, suggesting that the presence of health professionals in the prison may help control TB transmission and reduce medication resistance.
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Objective: Nontuberculous mycobacteria (NTM) are a heterogeneous group of bacteria that are widely distributed in nature and associated with opportunistic infections in humans. The aims of this study were to identify NTM in patients with suspected tuberculosis who presented positive cultures and to evaluate the genetic diversity of strains identified as Mycobacterium avium.

Methods: We studied pulmonary and extrapulmonary samples obtained from 1,248 patients.

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We report a case of fungal and mycobacterial co-infection in an immunosuppressed patient from Southern Brazil. Histoplasmosis was diagnosed in an AIDS patient admitted to the hospital with nonspecific respiratory signs. However, 4 months post hospital discharge, the patient worsened and a co-infection with was detected.

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Drug-resistant tuberculosis (DR-TB) is major problem in the fight against TB. Multidrug resistant (MDR) TB patients have a reduced treatment success rates and for, extensively drug-resistant (XDR) TB the cure rate does not exceed 25% in many countries. To evaluate the pre-XDR-TB and XDR-TB prevalence and transmission in Rio Grande do Sul State, in southern Brazil, we performed a retrospective WGS-based analysis of 87 MDR-TB cases, aiming to identify resistance-conferring mutations and its phylogenetic distinctiveness.

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In the last 15 years, has received special attention, mainly due to several resistance mechanisms and high rates of morbimortality. The ability to form biofilms contributes to the persistence of this microorganism in the hospital environment and facilitates the occurrence of nosocomial infections. Several studies have highlighted the pharmacological relevance of pyridines in the treatment and control of infectious diseases and others have related the anti- potential of hydrazine derivatives.

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Nosocomial transmission of is an important health issue and the detection of tuberculosis (TB) cases is the main tool for controlling this disease. We aimed to assess the possible occurrence of nosocomial transmission of in a reference hospital for HIV/AIDS patients and evaluate both the performance of the Xpert MTB/RIF (Xpert) platform and drug resistance profiles. We evaluated the performance of the Xpert platform.

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The basis of drug resistance in is still poorly understood. Nevertheless, as seen in other microorganisms, the efflux of antimicrobials may also play a role in drug resistance. Here, we investigated the role of efflux pumps in clarithromycin resistance using nine clinical isolates of complex belonging to the T28 (41) sequevar responsible for the inducible resistance to clarithromycin.

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Herein, we evaluated tetrahydropyridine (THP) compounds (NUNM) as antimicrobials and inhibitors of the efflux mechanism in M. abscessus. subsp.

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Tuberculosis (TB) in pinnipeds is typically caused by Mycobacterium pinnipedii, which has also been associated with infections in other species, such as cattle and humans. As a result, this pathogen has zoonotic potential and is a public health concern. In 2016, a female South American sea lion Otaria flavescens in southern Brazil presented with emaciation and severe dyspnea and died within 3 h of capture.

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