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1.
J Fish Biol ; 105(4): 1357-1361, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39109773

ABSTRACT

Sciadonus alphacrucis Melo, Gomes, Møller & Nielsen, 2022 is a rare deep-sea species, previously known from only two specimens collected off São Paulo State, southeastern Brazil, in the western South Atlantic. Herein, we report a new specimen of S. alphacrucis collected on the continental slope off Santa Catarina State, southern Brazil, thereby extending its known distribution by 420 km. Additionally, we provide the new meristic and morphometric data, the molecular identification using sequences of the cytochrome c oxidase subunit I (COI), an updated distribution map, and a discussion of troglomorphic traits.


Subject(s)
DNA Barcoding, Taxonomic , Electron Transport Complex IV , Animals , Brazil , Electron Transport Complex IV/genetics , Atlantic Ocean , Phylogeny , Animal Distribution , Female , Male , Fishes/genetics , Fishes/classification
2.
Curr Issues Mol Biol ; 46(7): 6489-6507, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-39057029

ABSTRACT

Tuberculosis is a highly lethal bacterial disease worldwide caused by Mycobacterium tuberculosis (Mtb). Caespitate is a phytochemical isolated from Helichrysum caespititium, a plant used in African traditional medicine that shows anti-tubercular activity, but its mode of action remains unknown. It is suggested that there are four potential targets in Mtb, specifically in the H37Rv strain: InhA, MabA, and UGM, enzymes involved in the formation of Mtb's cell wall, and PanK, which plays a role in cell growth. Two caespitate conformational structures from DFT conformational analysis in the gas phase (GC) and in solution with DMSO (CS) were selected. Molecular docking calculations, MM/GBSA analysis, and ADME parameter evaluations were performed. The docking results suggest that CS is the preferred caespitate conformation when interacting with PanK and UGM. In both cases, the two intramolecular hydrogen bonds characteristic of caespitate's molecular structure were maintained to achieve the most stable complexes. The MM/GBSA study confirmed that PanK/caespitate and UGM/caespitate were the most stable complexes. Caespitate showed favorable pharmacokinetic characteristics, suggesting rapid absorption, permeability, and high bioavailability. Additionally, it is proposed that caespitate may exhibit antibacterial and antimonial activity. This research lays the foundation for the design of anti-tuberculosis drugs from natural sources, especially by identifying potential drug targets in Mtb.

3.
MethodsX ; 12: 102690, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38638452

ABSTRACT

Mycobacterium tuberculosis (MTB) is known for its adaptive capability in developing resistance to antibiotics, through the selection of spontaneous mutations that arise during treatment. Generating spontaneous antibiotic-resistant mutants in vitro is challenging but necessary for studying this phenomenon. A protocol was designed and tested to select stable, MTB spontaneous, d-cycloserine (DCS) resistant mutants. Twenty-four colonies resistant to DCS were selected, demonstrating an increase between 1 and 4 times the Minimum Inhibitory Concentration (MIC) set for Mycobacterium tuberculosis H37Rv ATCC 27294 reference strain.

4.
Front Public Health ; 12: 1356932, 2024.
Article in English | MEDLINE | ID: mdl-38463163

ABSTRACT

Introduction: Rotavirus-associated diarrheal diseases significantly burden healthcare systems, particularly affecting infants under five years. Both Rotarix™ (RV1) and RotaTeq™ (RV5) vaccines have been effective but have distinct application schedules and limited interchangeability data. This study aims to provide evidence on the immunogenicity, reactogenicity, and safety of mixed RV1-RV5 schedules compared to their standard counterparts. Methods: This randomized, double-blind study evaluated the non-inferiority in terms of immunogenicity of mixed rotavirus vaccine schedules compared to standard RV1 and RV5 schedules in a cohort of 1,498 healthy infants aged 6 to 10 weeks. Participants were randomly assigned to one of seven groups receiving various combinations of RV1, and RV5. Standard RV1 and RV5 schedules served as controls of immunogenicity, reactogenicity, and safety analysis. IgA antibody levels were measured from blood samples collected before the first dose and one month after the third dose. Non-inferiority was concluded if the reduction in seroresponse rate in the mixed schemes, compared to the standard highest responding scheme, did not exceed the non-inferiority margin of -0.10. Reactogenicity traits and adverse events were monitored for 30 days after each vaccination and analyzed on the entire cohort. Results: Out of the initial cohort, 1,365 infants completed the study. Immunogenicity analysis included 1,014 infants, considering IgA antibody titers ≥20 U/mL as seropositive. Mixed vaccine schedules demonstrated non-inferiority to standard schedules, with no significant differences in immunogenic response. Safety profiles were comparable across all groups, with no increased incidence of serious adverse events or intussusception. Conclusion: The study confirms that mixed rotavirus vaccine schedules are non-inferior to standard RV1 and RV5 regimens in terms of immunogenicity and safety. This finding supports the flexibility of rotavirus vaccination strategies, particularly in contexts of vaccine shortage or logistic constraints. These results contribute to the global effort to optimize rotavirus vaccination programs for broader and more effective pediatric coverage.Clinical trial registration: ClinicalTrials.gov, NCT02193061.


Subject(s)
Rotavirus Infections , Rotavirus Vaccines , Humans , Infant , Diarrhea/virology , Immunoglobulin A , Rotavirus Infections/complications , Rotavirus Infections/prevention & control , Rotavirus Vaccines/adverse effects , Double-Blind Method
5.
Mar Pollut Bull ; 197: 115717, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37924737

ABSTRACT

The presence of marine litter in the deep ocean (>200 m depth) may represent an invisible threat that has been neglected due to the scarcity of data. Herein, we provide the first report of persistent marine litter on the Southwestern Atlantic continental slope. Marine litter was collected onboard the Brazilian R/V Alpha Crucis, using bottom trawling, in 28 out of 31 sampled stations, between 274 and 1520 m depth, in two distinct areas off the southern Brazilian coast. In total, 603 items and 13.8 kg of litter were collected and classified according to the type of material. Plastic was the most frequent and most abundant material found. Although there was no bathymetric variation along the slope, density of litter was considerably higher off São Paulo than off Santa Catarina State, supposedly due to the heavier presence of oil and gas platforms and large cargo vessels.


Subject(s)
Environmental Monitoring , Plastics , Brazil , Waste Products/analysis
6.
J Pediatr ; 259: 113461, 2023 08.
Article in English | MEDLINE | ID: mdl-37172809

ABSTRACT

OBJECTIVE: To evaluate vaccine effectiveness (VE) of a live oral pentavalent rotavirus vaccine (RotaTeq, RV5) among young children in Shanghai, China, via a test-negative design study. STUDY DESIGN: We consecutively recruited children visiting a tertiary children's hospital for acute diarrhea from November 2021 to February 2022. Information on clinical data and rotavirus vaccination was collected. Fresh fecal samples were obtained for rotavirus detection and genotyping. To evaluate VE of RV5 against rotavirus gastroenteritis among young children, unconditional logistic regression models were conducted to compare ORs for vaccination between rotavirus-positive cases and test-negative controls. RESULTS: A total of 390 eligible children with acute diarrhea were enrolled, including 45 (11.54%) rotavirus-positive cases and 345 (88.46%) test-negative controls. After excluding 4 cases (8.89%) and 55 controls (15.94%) who had received the Lanzhou lamb rotavirus vaccine, 41 cases (12.39%) and 290 controls (87.61%) were included for the evaluation of RV5 VE. After adjustment for potential confounders, the 3-dose RV5 vaccination showed 85% (95% CI, 50%-95%) VE against mild to moderate rotavirus gastroenteritis among children aged 14 weeks to ≤4 years and 97% (95% CI, 83%-100%) VE among children aged 14 weeks to ≤2 years with genotypes G8P8, G9P8, and G2P4 represented 78.95%, 18.42%, and 2.63% of circulation strains, respectively. CONCLUSIONS: A 3-dose vaccination of RV5 is highly protective against rotavirus gastroenteritis among young children in Shanghai. The G8P8 genotype prevailled in Shanghai after RV5 introduction.


Subject(s)
Gastroenteritis , Rotavirus Infections , Rotavirus Vaccines , Rotavirus , Humans , Rotavirus Vaccines/therapeutic use , Gastroenteritis/epidemiology , Gastroenteritis/prevention & control , Vaccines, Combined , China/epidemiology , Rotavirus Infections/epidemiology , Rotavirus Infections/prevention & control , Diarrhea/epidemiology , Diarrhea/prevention & control , Vaccination , Hospitalization
7.
Biomolecules ; 13(2)2023 01 28.
Article in English | MEDLINE | ID: mdl-36830617

ABSTRACT

The increasing emergence of Mycobacterium tuberculosis (Mtb) strains resistant to traditional anti-tuberculosis drugs has alarmed health services worldwide. The search for new therapeutic targets and effective drugs that counteract the virulence and multiplication of Mtb represents a challenge for the scientific community. Several studies have considered the erp gene a possible therapeutic target in the last two decades, since its disruption negatively impacts Mtb multiplication. This gene encodes the exported repetitive protein (Erp), which is located in the cell wall of Mtb. In vitro studies have shown that the Erp protein interacts with two putative membrane proteins, Rv1417 and Rv2617c, and the impairment of their interactions can decrease Mtb replication. In this study, we present five nicotine analogs that can inhibit the formation of heterodimers and trimers between these proteins. Through DFT calculations, molecular dynamics, docking, and other advanced in silico techniques, we have analyzed the molecular complexes, and show the effect these compounds have on protein interactions. The results show that four of these analogs can be possible candidates to counteract the pathogenicity of Mtb. This study aims to combine research on the Erp protein as a therapeutic target in the search for new drugs that serve to create new therapies against tuberculosis disease.


Subject(s)
Mycobacterium tuberculosis , Membrane Proteins/metabolism , Nicotine/pharmacology , Virulence Factors/metabolism , Virulence , Bacterial Proteins/metabolism
8.
J Ultrasound ; 2022 Sep 25.
Article in English | MEDLINE | ID: mdl-36153781

ABSTRACT

Prone position has shown beneficial hemodynamic effects in patients with right ventricular dysfunction associated with acute respiratory distress syndrome decreasing the right ventricle afterload. We describe the case of a 57-year-old man with right ventricular dysfunction associated with pulmonary thromboembolism with severe hypoxemia that required mechanical ventilation in prone position. With this maneuver, we verified an improvement not only in his oxygenation, but also in his right ventricular function assessed with speckle tracking echocardiography. Our case shows the potential beneficial effect of the prone position maneuver in severely hypoxemic patients with right ventricular dysfunction associated with pulmonary thromboembolism.

9.
Polymers (Basel) ; 14(13)2022 Jun 25.
Article in English | MEDLINE | ID: mdl-35808623

ABSTRACT

Nowadays, tuberculosis is the second leading cause of death from a monopathogenic transmitted disease, only ahead of COVID-19. The role of exported repetitive protein (Erp) in the virulence of Mycobacterium tuberculosis has been extensively demonstrated. In vitro and in vivo assays have identified that Erp interacts with Rv1417 and Rv2617c proteins, forming putative transient molecular complexes prior to localization to the cell envelope. Although new insights into the interactions and functions of Erp have emerged over the years, knowledge about its structure and protein-protein interactions at the atomistic level has not been sufficiently explored. In this work, we have combined several in silico methodologies to gain new insights into the structural relationship between these proteins. Two system conditions were evaluated by MD simulations: Rv1417 and Rv2617c embedded in a lipid membrane and another with a semi-polar solvent to mimic the electrostatic conditions on the membrane surface. The Erp protein was simulated as an unanchored structure. Stabilized structures were docked, and complexes were evaluated to recognize the main residues involved in protein-protein interactions. Our results show the influence of the medium on the structural conformation of proteins. Globular conformations were favored under high polarity conditions and showed a higher energetic affinity in complex formation. Meanwhile, disordered conformations were favored under semi-polar conditions and an increase in the number of contacts between residues was observed. In addition, the electrostatic potential analysis showed remarkable changes in protein interactions due to the polarity of the medium, demonstrating the relevance of Erp protein in heterodimer formation. On the other hand, contact analysis showed that several C-terminal residues of Erp were involved in the protein interactions, which seems to contradict experimental observations; however, these complexes could be transient forms. The findings presented in this work are intended to open new perspectives in the studies of Erp protein molecular interactions and to improve the knowledge about its function and role in the virulence of Mycobacterium tuberculosis.

10.
Rev. biol. trop ; Rev. biol. trop;69(3)sept. 2021.
Article in English | LILACS, SaludCR | ID: biblio-1387677

ABSTRACT

Abstract Introduction: Coastal ecosystems worldwide are under the influence of local, regional and global stressors, such as pollution, eutrophication and climate change. Golfo Dulce is a relatively pristine and accessible deep tropical ecosystem that provides opportunities for comparative and collaborative research. Objective: To summarize published reports on past research conducted in this ecosystem, identify topics for further study, and suggest new research issues. Methods: A search was made on the web for reports based on research conducted in Golfo Dulce and published in scientific journals. Reports focusing on environmental parameters and on the biota were included. Results: A total of 123 studies that include data from Golfo Dulce are cited. The four topics more frequently addressed were reports based on the results of the R/V Victor Hensen expedition (1993-1994) and follow-up work on microbiology, studies on water parameters, research on vertebrates, and zooplankton studies. The reports focusing on vertical profiles of oxygen and temperature are discussed in detail, followed by those on the biota. Conclusions: Golfo Dulce has low oxygen concentrations below 50 m and is frequently anoxic at the 200 m deep basin with occasional formation of H2S. However, the ecosystem contains a relatively high diversity of identified organisms, from bacteria to whales. Of particular relevance for future studies are multidisciplinary surveys aiming at obtaining data on primary productivity, the diversity and biomass of the main groups of planktonic, demersal and benthic organisms, and the frequency and magnitude of the influx of deep offshore waters over the sill into the basin. These data, as well as the information gathered in the past, are essential for updating the trophic model developed more than 25 years ago and in support of new predictive models on the functioning of the ecosystem.


Resumen Introducción: Los ecosistemas costeros alrededor del mundo están bajo la influencia de tensores locales, regionales y globales, como la contaminación, la eutroficación y el cambio climático. El Golfo Dulce es un profundo ecosistema tropical relativamente inalterado y accesible, que provee oportunidades para la investigación comparativa y colaborativa. Objetivo: Resumir los informes publicados sobre investigaciones pasadas realizadas en el ecosistema, identificar tópicos para estudios futuros y sugerir nuevas áreas de investigación. Métodos: Se hizo una búsqueda en la red de informes basados en investigaciones hechas en Golfo Dulce y publicadas en revistas científicas. Fueron incluidos aquellos informes sobre parámetros ambientales y la biota. Resultados: Un total de 123 estudios que incluyen datos sobre Golfo Dulce son citados. Los cuatro tópicos citados con más frecuencia fueron: Los resultados de la expedición del R/V Victor Hensen (1993-1994) y estudios de seguimiento sobre microbiología, informes sobre parámetros acuáticos, investigaciones sobre vertebrados y estudios sobre zooplancton. Los informes sobre perfiles de oxígeno y temperatura son presentados con mayor detalle, seguidos por aquellos sobre la biota. Conclusiones: Golfo Dulce tiene bajas concentraciones de oxígeno por debajo de 50 m y es usualmente anóxico a 200 m en el fondo, con formación ocasional de H2S. Sin embargo, el ecosistema contiene una diversidad de organismos identificados relativamente alta, desde bacterias hasta ballenas. De relevancia particular para futuros estudios es, entre otros, la conducción, de muestreos multidisciplinarios orientados a obtener datos sobre productividad primaria, la diversidad y biomasa de los principales grupos de organismos planctónicos, demersales y bénticos, así como la frecuencia y magnitud del flujo de agua oceánica hacia el interior. Estos datos, así como los obtenidos en el pasado, son esenciales para actualizar el modelo trófico desarrollado hace más de 25 años, o en apoyo de nuevos modelos predictivos de funcionamiento del ecosistema.


Subject(s)
Tropical Ecosystem , Environmental Change , Climate Change , Costa Rica
11.
Front Microbiol ; 11: 570794, 2020.
Article in English | MEDLINE | ID: mdl-33193164

ABSTRACT

Tuberculosis, a lung disease caused by Mycobacterium tuberculosis (Mtb), is one of the ten leading causes of death worldwide affecting mainly developing countries. Mtb can persist and survive inside infected cells through modulation of host antibacterial attack, i.e., by avoiding the maturation of phagosome containing mycobacteria to more acidic endosomal compartment. In addition, bacterial phosphatases play a central role in the interplay between host cells and Mtb. In this study, we characterized the Rv2577 of Mtb as a potential alkaline phosphatase/phosphodiesterase enzyme. By an in vitro kinetic assay, we demonstrated that purified Rv2577 expressed in Mycobacterium smegmatis displays both enzyme activities, as evidenced by using the artificial substrates p-NPP and bis-(p-NPP). In addition, a three-dimensional model of Rv2577 allowed us to define the catalytic amino acid residues of the active site, which were confirmed by site-directed mutagenesis and enzyme activity analysis, being characteristic of a member of the metallophosphatase superfamily. Finally, a mutation introduced in Rv2577 reduced the replication of Mtb in mouse organs and impaired the arrest of phagosomes containing mycobacteria in early endosomes; which indicates Rv2577 plays a role in Mtb virulence.

12.
J Bacteriol ; 202(2)2020 01 02.
Article in English | MEDLINE | ID: mdl-31636108

ABSTRACT

Mycobacterium tuberculosis nicotinamidase-pyrazinamidase (PZAse) is a metalloenzyme that catalyzes conversion of nicotinamide-pyrazinamide to nicotinic acid-pyrazinoic acid. This study investigated whether a metallochaperone is required for optimal PZAse activity. M. tuberculosis and Escherichia coli PZAses (PZAse-MT and PZAse-EC, respectively) were inactivated by metal depletion (giving PZAse-MT-Apo and PZAse-EC-Apo). Reactivation with the E. coli metallochaperone ZnuA or Rv2059 (the M. tuberculosis analog) was measured. This was repeated following proteolytic and thermal treatment of ZnuA and Rv2059. The CDC1551 M. tuberculosis reference strain had the Rv2059 coding gene knocked out, and PZA susceptibility and the pyrazinoic acid (POA) efflux rate were measured. ZnuA (200 µM) achieved 65% PZAse-EC-Apo reactivation. Rv2059 (1 µM) and ZnuA (1 µM) achieved 69% and 34.3% PZAse-MT-Apo reactivation, respectively. Proteolytic treatment of ZnuA and Rv2059 and application of three (but not one) thermal shocks to ZnuA significantly reduced the capacity to reactivate PZAse-MT-Apo. An M. tuberculosis Rv2059 knockout strain was Wayne positive and susceptible to PZA and did not have a significantly different POA efflux rate than the reference strain, although a trend toward a lower efflux rate was observed after knockout. The metallochaperone Rv2059 restored the activity of metal-depleted PZAse in vitro Although Rv2059 is important in vitro, it seems to have a smaller effect on PZA susceptibility in vivo. It may be important to mechanisms of action and resistance to pyrazinamide in M. tuberculosis Further studies are needed for confirmation.IMPORTANCE Tuberculosis is an infectious disease caused by the bacterium Mycobacterium tuberculosis and remains one of the major causes of disease and death worldwide. Pyrazinamide is a key drug used in the treatment of tuberculosis, yet its mechanism of action is not fully understood, and testing strains of M. tuberculosis for pyrazinamide resistance is not easy with the tools that are presently available. The significance of the present research is that a metallochaperone-like protein may be crucial to pyrazinamide's mechanisms of action and of resistance. This may support the development of improved tools to detect pyrazinamide resistance, which would have significant implications for the clinical management of patients with tuberculosis: drug regimens that are appropriately tailored to the resistance profile of a patient's individual strain lead to better clinical outcomes, reduced onward transmission of infection, and reduction of the development of resistant strains that are more challenging and expensive to treat.


Subject(s)
Mycobacterium tuberculosis/enzymology , Nicotinamidase/metabolism , Pyrazinamide/pharmacology , Antitubercular Agents/pharmacology , Drug Resistance, Bacterial/drug effects , Escherichia coli/drug effects , Escherichia coli/enzymology , Metallochaperones , Microbial Sensitivity Tests , Mycobacterium tuberculosis/drug effects , Pyrazinamide/analogs & derivatives
13.
Ci. Rural ; 50(12): e20180931, 2020. ilus
Article in English | VETINDEX | ID: vti-29595

ABSTRACT

Foodborne diseases are often related to consumption of contaminated food or water. Viral agents are important sources of contamination and frequently reported in food of animal origin. The goal of this study was to detect emerging enteric viruses in samples of industrialized foods of animal origin collected in establishments from southern of Brazil. In the analyzed samples, no Hepatitis E virus (HEV) genome was detected. However, 21.8% (21/96) of the samples were positive for Rotavirus (RVA) and 61.4% (59/96) for Adenovirus (AdV), including Human adenovirus-C (HAdV-C), Porcine adenovirus-3 (PAdV-3) and new type of porcine adenovirus PAdV-SVN1. In the present research, PAdV-SVN1 was detected in foods for the first time. The presence of these viruses may be related to poor hygiene in sites of food preparation, production or during handling.(AU)


As doenças transmitidas por alimentos são frequentemente descritas e relacionadas ao consumo de alimentos ou água contaminados, sendo alguns agentes virais importantes fontes de contaminação e frequentemente encontrados em alimentos de origem animal. O objetivo deste trabalho foi detectar patógenos entéricos emergentes em amostras de alimentos industrializados de origem animal coletados em estabelecimentos da região sul do Brasil. Nas amostras analisadas, não foi detectado o genoma do vírus da Hepatite E (HEV). No entanto, 21,8% (21/96) das amostras foram positivas para Rotavírus (RV) e 61,4% (59/96) para adenovírus (AdV), incluindo Adenovírus humano-C (HAdV-C), Adenovírus porcino-3 (PAdV-3) e novo tipo de suíno adenovírus PAdV-SVN1. No presente trabalho, é descrito pela primeira vez em alimentos a presença de PAdV-SVN1. A presença desses vírus pode estar relacionada à falta de higiene em locais de preparo de alimentos, manipulação de produção.(AU)


Subject(s)
Animals , Red Meat/analysis , Swine Diseases , Adenoviruses, Porcine , Industrialized Foods , Food Contamination
14.
Ciênc. rural (Online) ; 50(12): e20180931, 2020. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1133245

ABSTRACT

ABSTRACT: Foodborne diseases are often related to consumption of contaminated food or water. Viral agents are important sources of contamination and frequently reported in food of animal origin. The goal of this study was to detect emerging enteric viruses in samples of industrialized foods of animal origin collected in establishments from southern of Brazil. In the analyzed samples, no Hepatitis E virus (HEV) genome was detected. However, 21.8% (21/96) of the samples were positive for Rotavirus (RVA) and 61.4% (59/96) for Adenovirus (AdV), including Human adenovirus-C (HAdV-C), Porcine adenovirus-3 (PAdV-3) and new type of porcine adenovirus PAdV-SVN1. In the present research, PAdV-SVN1 was detected in foods for the first time. The presence of these viruses may be related to poor hygiene in sites of food preparation, production or during handling.


RESUMO: As doenças transmitidas por alimentos são frequentemente descritas e relacionadas ao consumo de alimentos ou água contaminados, sendo alguns agentes virais importantes fontes de contaminação e frequentemente encontrados em alimentos de origem animal. O objetivo deste trabalho foi detectar patógenos entéricos emergentes em amostras de alimentos industrializados de origem animal coletados em estabelecimentos da região sul do Brasil. Nas amostras analisadas, não foi detectado o genoma do vírus da Hepatite E (HEV). No entanto, 21,8% (21/96) das amostras foram positivas para Rotavírus (RV) e 61,4% (59/96) para adenovírus (AdV), incluindo Adenovírus humano-C (HAdV-C), Adenovírus porcino-3 (PAdV-3) e novo tipo de suíno adenovírus PAdV-SVN1. No presente trabalho, é descrito pela primeira vez em alimentos a presença de PAdV-SVN1. A presença desses vírus pode estar relacionada à falta de higiene em locais de preparo de alimentos, manipulação de produção.

15.
Vaccimonitor (La Habana, Print) ; 28(2)mayo.-ago. 2019. tab, graf
Article in English | LILACS, CUMED | ID: biblio-1094626

ABSTRACT

Mycobacterium tuberculosis (Mtb) is a leading cause of death globally. Latent tuberculosis infection threatens 1.7 billion people. Mtb latency is mediated by a group of proteins, mainly coded by the Dormancy Safety Regulator (DosR). The protein Rv2626c is the strongest regulated member of this operon. Previous results, including ours, indicate a strong potential of Rv2626c as antigen in a new multiple tuberculosis vaccine. Objectives of this study were to purify the rRv2626c protein and characterize it physico-chemically and immunologically. The purified protein migrates as a sole band after a non-reductive PAGE-silver staining. Under reductive conditions, the dimer isoform appearing at 30.9 kDa prevails over the monomer 15.6 kDa. Mass spectrometry corroborates electrophoresis results regarding dimer molecular weight, of approximately 32 kDa. Six of its digested peptides matched those of HRP-1 protein (Rv2626c) of Mtb whereas 92.1 percent of its amino acid sequence contains three mutations and the addition of an amino acid. With respect to native Mtb protein, 12 of the 13 main epitopes are conserved. Antigenicity was corroborated in volunteers, the antibody responses were significantly higher in a number of infected tuberculosis patients in comparison to healthy Mantoux negative donors as well as in mice immunized with reference Rv2626c, while the immune identification pattern was as expected. The purified protein was able to elicit strong immune response in mice and the resulting antibodies recognized the reference Rv2626c protein. Lastly, the productive specific yield of the Streptomyces lividans strain is sustainable. Taking these results altogether, corroborates our rRv2626c as a promising candidate as antigen for new tuberculosis vaccine formulations(AU)


Mycobacterium tuberculosis (Mtb) es una de las principales causas de muerte globalmente, la tuberculosis latente amenaza a 1,7 mil millones de personas. En combinación con el VIH-SIDA y otras enfermedades, la tuberculosis puede ser reactivada. La latencia de Mtb está mediada por un grupo de proteínas, principalmente codificadas por el Regulador de Seguridad de Latencia (DosR). La proteína Rv2626c es el miembro más fuertemente regulado de este operón. Los resultados previos, incluidos los nuestros, indican una gran potencialidad de Rv2626c como antígeno en una nueva vacuna múltiple contra la tuberculosis. Los objetivos de este estudio fueron purificar la proteína Rv2626c y caracterizarla fisicoquímica e inmunológicamente. La proteína purificada migra como una banda única después de PAGE con tinción de plata en condiciones no reductoras. En condiciones reductoras, el dímero, de 30,9 kDa, es la isoforma prevaleciente sobre el monómero, de 15,6 kDa. La espectrometría de masas corrobora el peso molecular del dímero, de aproximadamente 32 kDa. Seis de sus péptidos digeridos coincidieron con los de la proteína Rv2626c de Mtb, mientras que se confirmó coincidencia del 92,1 por ciento de su secuencia de aminoácidos, detectándose tres mutaciones y la adición de un aminoácido. Con respecto a la proteína Mtb nativa, se conservan 12 de los 13 epítopes principales. La antigenicidad se corroboró en voluntarios, las respuestas de anticuerpos fueron significativamente mayores en un número de pacientes infectados con tuberculosis en comparación con los donantes negativos de Mantoux sanos, así como en ratones inmunizados con la referencia Rv2626c, mientras que el patrón de identificación inmune fue el esperado. La proteína purificada fue capaz de provocar una fuerte respuesta inmune en ratones y los anticuerpos resultantes reconocieron la proteína de referencia Rv2626c. Por último, el rendimiento productivo específico de la cepa de Streptomyces lividans es sostenible. Tomando estos resultados en conjunto, corrobora nuestra rRv2626c como un candidato prometedor como antígeno para nuevas formulaciones de vacunas contra la tuberculosis(AU)


Subject(s)
Humans , Male , Female , Recombinant Proteins , Streptomyces lividans , Latent Tuberculosis/mortality , Mycobacterium tuberculosis , Vaccines , Tuberculosis Vaccines/therapeutic use
16.
Tuberculosis (Edinb) ; 113: 19-25, 2018 12.
Article in English | MEDLINE | ID: mdl-30514503

ABSTRACT

Mycobacterium tuberculosis remains as a threat to public health around the world with 1.7 million cases of TB-associated deaths during 2016. Despite the use of Bacillus Calmette-Guerin (BCG) vaccine, control of the infection has not been successful. Because of this, several efforts have been made in order to develop new vaccines capable of boosting previous immunization or attempted for replacing current BCG. We previously showed that over expression of the M. tuberculosis adenylyl cyclase encoding gene Rv2212 in BCG bacilli (BCG-Rv2212), induced an attenuated phenotype when administered in BALB/c mice. Moreover, two-dimensional proteomic analysis showed that heat shock proteins such as GroEL2 and DnaK were overexpressed in this BCG-Rv2212. In this report, we show that immunization of mice with BCG-Rv2212 significantly increments IFN-γ+ CD4+ and CD8+ T-lymphocytes after PPD stimulation in comparison with BCG vaccinated mice. Mice vaccinated with BCG-Rv2212 significantly reduced the bacterial load in lungs after four-month post infection with M. tuberculosis H37Rv but was similar to BCG after 6 month-post-challenge. Survival experiment showed that both vaccines administered separately in mice induce similar levels of protection after 20-week post-challenge with M. tuberculosis H37Rv. Virulence experiments developed in nude mice, showed that BCG-Rv2212 and BCG bacilli were equally safe. Our results suggest that BCG-Rv2212 is capable of stimulating cellular immune response effectively and reduce bacterial burden in lungs of mice after challenge. Particularly, it seems to be more effective in controlling bacterial burden during the first steps of infection.


Subject(s)
Adenylyl Cyclases/administration & dosage , BCG Vaccine/administration & dosage , Bacterial Proteins/administration & dosage , Immunogenicity, Vaccine , Lung/microbiology , Mycobacterium tuberculosis/growth & development , Tuberculosis, Pulmonary/prevention & control , Adenylyl Cyclases/genetics , Adenylyl Cyclases/immunology , Animals , BCG Vaccine/genetics , BCG Vaccine/immunology , Bacterial Load , Bacterial Proteins/genetics , Bacterial Proteins/immunology , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/microbiology , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/microbiology , Disease Models, Animal , Female , Immunity, Cellular , Immunization , Lung/immunology , Mice, Inbred BALB C , Mice, Nude , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/immunology , Tuberculosis, Pulmonary/immunology , Tuberculosis, Pulmonary/microbiology , Vaccines, DNA/administration & dosage
17.
Vaccimonitor (La Habana, Print) ; 27(3)set.-dic. 2018. ilus, tab
Article in Spanish | LILACS, CUMED | ID: biblio-1094611

ABSTRACT

Streptomyces lividans, ha ganado gran atención en los últimos tiempos, como vector de expresión y producción de proteínas de Mycobacterium tuberculosis de interés biomédico, como alternativa a su obtención tradicional en E. coli. La proteína Rv2626c, Proteína de Respuesta Hipóxica 1, es codificada por el gen Rv2626c (hrp1) de M. tuberculosis, perteneciente al regulón de la fase de latencia DosR. Esta proteína se sobre-expresa en la fase de latencia de la tuberculosis bajo condiciones de estrés como hipoxia y bajos niveles, de óxido nítrico. Se ha demostrado la inmunogenicidad y capacidad de esta proteína, de inducir citocinas características del patrón Th-1, tales como el interferón gamma. Por ello, nuestro grupo logró la obtención de Rv2626c por la tecnología del ADN recombinante usando como cepa hospedera Streptomyces lividans TK24. Con el objetivo de aumentar el nivel de expresión de la proteína recombinante, rRv2626c en este trabajo se ensayaron diferentes medios de cultivo, evaluando el crecimiento de la cepa transformada en condiciones de zaranda. Se determinó la cinética de crecimiento en el medio definido, formulado industrialmente en el Centro Nacional de Biopreparados: caldo Triptona Soya (TSB-BioCen) y en medio de cultivo equivalente preparado en el laboratorio. Para establecer la cinética de crecimiento, se utilizó el cálculo del peso seco y la determinación de la concentración de proteínas totales por la técnica de ácido bicinconinico (BCA) a diferentes tiempos del cultivo. Posteriormente, se identificó la proteína clonada mediante SDS-PAGE y Western Blotting, así como los niveles de expresión mediante análisis densitométrico. Los resultados indican que se alcanzaron los máximos niveles de densidad celular a las 36 h de cultivo y los más altos niveles de expresión proteica total y específica entre las 42 y 54 h. Con el medio químicamente definido TSB-Biocen preformulado en lugar del preparado en el laboratorio partiendo de los componentes, se logró reducir el tiempo óptimo para la expresión-secreción de la proteína rv2626c de 96 a 54 h. Los mejores resultados en la promoción de la expresión de la proteína recombinante se lograron con el medio definido TSB-BioCen, a las 48 h con 8,5% de rendimiento específico, superando en más de 10 veces los niveles de crecimiento celular obtenidos con el medio elaborado en el laboratorio y más de dos veces los niveles de secreción de la proteína recombinante(AU)


The use of Streptomyces as a bacterial cell factory for the secretory production of bio-active Mycobacterium tuberculosis proteins have gained a lot of attention in recent years, as a convenient alternative to the traditionally used Escherichia coli. The protein Rv2626c protein, also known as Hypoxic Response Protein 1 (HRP1), is encoded by the gene rv2626c (hrp1) of M. tuberculosis which belongs to the Dormancy Safety Regulator (DosR) regulon. This protein is over-expressed during the latency phase of tuberculosis under stress related conditions such as hypoxia and low, non-toxic, levels of nitric oxide and, the immunogenicity and ability to induce cytokines characteristic of the Th-1 pattern of this protein, such as gamma interferon, have been demonstrated. On this basis, our working group, succeeded in obtaining rRv2626c via recombinant DNA technology using Streptomyces lividans TK24 as the host cell. To improve the expression level of the protein, different culture media were used to evaluate the growth of the transformed strain in shaken flask conditions. Growth kinetic for the recombinant strain was evaluated in defined media of preformulated tryptic soya broth (TSB-Biocen), through the determination of dry weight as well as total protein concentration by Bicinconinic acid assay (BCA). Protein identification was done by SDS-PAGE, Western Blot and its expression level by densitometric analysis. Our results indicated a maximal cell density at 36 h of culture, with higher concentration of total and specific protein at 42-54 h in comparison with previous media used. With the chemically defined media a preformulated TSB-Biocen rather than individual components, culture time for expression/secretion of rRv2626c was reduced from 96 h to 54 h. The best results in expression-secretion levels of rv2626c protein were obtained with the TSB-Biocen defined media at 48 h of culture with 8.5% of specific yield. More than 10 fold increase in cellular growth and more than 2 fold increase in specific yield(AU)


Subject(s)
Culture Media , Streptomyces lividans , Mycobacterium tuberculosis
18.
Food Environ Virol ; 10(4): 365-372, 2018 12.
Article in English | MEDLINE | ID: mdl-30206760

ABSTRACT

The aim of this study was to investigate hepatitis A virus (HAV), hepatitis E (HEV), and rotavirus (RV) in fresh and processed meat traded on the border of Brazil with Argentina and Uruguay. In total, 159 samples of raw and processed foods of animal origin were collected in Paso de los Libres, Argentina (n = 53 raw meat, n = 24 processed meat) and Rivera, Uruguay (n = 55 raw meat, n = 18 processed meat), or were seized by the Brazilian International Agricultural Surveillance System-VIGIAGRO (Brazil-Argentina border) (n = 8 raw meat, n = 1 bush meat). All samples were tested for the presence of HAV, HEV, and RV genomes. HAV genes were detected in 18.23% of samples and RV genes in 23.89%. No HEV-positive samples were detected. HAV was also detected in two of the VIGIAGRO samples. Processed meats from Argentina and Uruguay had a higher rate of HAV and RV than raw meat (P > 0.05). The median HAV in the Argentinian and Uruguayan samples was 6.9 × 104 and 3.5 × 103 copies/g, respectively. The presence of RV viral genes in raw meats from Argentina was significant, and this was not observed in processed meats. The presence of HAV and RV genes in a significant portion of products from Argentina and Uruguay is a potential source of human infection. This also indicates precarious conditions of acquisition, processing, and manipulation, which could be improved by improved regulation of food across borders.


Subject(s)
Food Contamination , Hepatitis A virus/isolation & purification , Hepatitis E virus/isolation & purification , Meat Products/virology , Meat/virology , Rotavirus/isolation & purification , Animals , Argentina , Brazil , Hepatitis A virus/genetics , Hepatitis E virus/genetics , Humans , Rotavirus/genetics , Uruguay
19.
Rev. chil. neuro-psiquiatr ; Rev. chil. neuro-psiquiatr;56(2): 127-135, jun. 2018. tab
Article in Spanish | LILACS | ID: biblio-959465

ABSTRACT

Resumen Las dos últimas décadas han sido testigos de la aparición de la realidad virtual (RV) como una herramienta importante para la investigación, evaluación y tratamiento en los trastornos mentales en la salud mental, creando entornos interactivos generados por computadora, donde los individuos pueden experimentar repetidamente sus situaciones problemáticas y aprender, a través de tratamientos psicológicos basados en la evidencia, cómo superar dificultades. El propósito de este artículo es proporcionar una revisión sistemática actualizada de la literatura sobre la utilización de la RV en los problemas de salud mental. Se realizó una revisión sistemática identificando 245 estudios, de los cuales se utilizaron solo 29 relacionados con modelos de RV, de los cuales 18 correspondían a distintos trastornos (ansiedad, depresión, esquizofrenia, psicosis, trastornos alimenticios, trastorno obsesivo compulsivo) y 11 a estudios empíricos; de su análisis se concluye que la capacidad de la RV para simular la realidad podría aumentar en gran medida el acceso a las terapias en los trastornos mentales mientras que los resultados podrían ser mejorados por la capacidad de la tecnología para crear nuevas realidades.


The last two decades have witnessed the emergence of virtual reality (VR) as an important tool for research, evaluation and treatment in mental disorders in mental health, creating interactive environments generated by computer, where individuals can repeatedly experience their problematic situations and learn, through psychological treatments based on evidence, how to overcome difficulties. The purpose of this article is to provide an updated systematic review of the literature on the use of VR in mental health problems. A systematic review was made identifying 245 studies, of which only 29 were used related to RV models, of which 18 corresponded to different disorders (anxiety, depression, schizophrenia, psychosis, eating disorders, obsessive compulsive disorder) and 11 to empirical studies. From their analysis it is concluded that the ability of the RV to simulate reality could greatly increase access to therapies in mental disorders while the results could be improved by the ability of technology to create new realities.


Subject(s)
Humans , Virtual Reality Exposure Therapy/methods , Virtual Reality , Mental Disorders/diagnosis , Mental Disorders/therapy , Mental Health
20.
Bioorg Med Chem ; 26(9): 2401-2409, 2018 05 15.
Article in English | MEDLINE | ID: mdl-29650461

ABSTRACT

Mycobacterium tuberculosis is considered one of the most successful pathogens in the history of mankind, having caused 1.7 million deaths in 2016. The amount of resistant and extensively resistant strains has increased; BCG has been the only vaccine to be produced in more than 100 years though it is still unable to prevent the disease's most disseminated form in adults; pulmonary tuberculosis. The search is thus still on-going for candidate antigens for an antituberculosis vaccine. This paper reports the use of a logical and rational methodology for finding such antigens, this time as peptides derived from the Rv3587c membrane protein. Bioinformatics tools were used for predicting mycobacterial surface location and Rv3587c protein structure whilst circular dichroism was used for determining its peptides' secondary structure. Receptor-ligand assays identified 4 high activity binding peptides (HABPs) binding specifically to A549 alveolar epithelial cells and U937 monocyte-derived macrophages, covering the region between amino acids 116 and 193. Their capability for inhibiting Mtb H37Rv invasion was evaluated. The recognition of antibodies from individuals suffering active and latent tuberculosis and from healthy individuals was observed in HABPs capable of avoiding mycobacterial entry to host cells. The results showed that 8 HABPs inhibited such invasion, two of them being common for both cell lines: 39265 (155VLAAYVYSLDNKRLWSNLDT173) and 39266 (174APSNETLVKTFSPGEQVTTY192). Peptide 39265 was the least recognised by antibodies from the individuals' sera evaluated in each group. According to the model proposed by FIDIC regarding synthetic vaccine development, peptide 39265 has become a candidate antigen for an antituberculosis vaccine.


Subject(s)
Antigens, Bacterial/immunology , Bacterial Proteins/immunology , Membrane Proteins/immunology , Mycobacterium tuberculosis/physiology , Peptide Fragments/immunology , Tuberculosis Vaccines/immunology , Amino Acid Sequence , Antigens, Bacterial/metabolism , Antigens, Bacterial/toxicity , Bacterial Proteins/chemical synthesis , Bacterial Proteins/metabolism , Bacterial Proteins/toxicity , Cell Line, Tumor , Computational Biology , Drug Design , Host-Pathogen Interactions/drug effects , Host-Pathogen Interactions/physiology , Humans , Membrane Proteins/chemical synthesis , Membrane Proteins/metabolism , Membrane Proteins/toxicity , Peptide Fragments/chemical synthesis , Peptide Fragments/metabolism , Peptide Fragments/toxicity , Protein Structure, Secondary , Protein Structure, Tertiary , Receptors, Cell Surface/metabolism , Tuberculosis Vaccines/chemical synthesis , Tuberculosis Vaccines/metabolism , Tuberculosis Vaccines/toxicity , Vaccines, Synthetic/immunology , Vaccines, Synthetic/metabolism , Vaccines, Synthetic/toxicity
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