Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Artigo em Inglês | MEDLINE | ID: mdl-31357451

RESUMO

The origin of the hepatitis B virus is a subject of wide deliberation among researchers. As a result, increasing academic interest has focused on the spread of the virus in different animal species. However, the sources of viral infection for many of these animals are unknown since transmission may occur from animal to animal, human to human, animal to human, and human to animal. The aim of this study was to evaluate hepadnavirus circulation in wild and farm animals (including animals raised under wild or free conditions) from different sites in Brazil and Uruguay using serological and molecular tools. A total of 487 domestic wild and farm animals were screened for hepatitis B virus (HBV) serological markers and tested via quantitative and qualitative polymerase chain reaction (PCR) to detect viral DNA. We report evidence of HBsAg (surface antigen of HBV) and total anti-HBc (HBV core antigen) markers as well as low-copy hepadnavirus DNA among domestic and wild animals. According to our results, which were confirmed by partial genome sequencing, as the proximity between humans and animals increases, the potential for pathogen dispersal also increases. A wider knowledge and understanding of reverse zoonoses should be sought for an effective One Health response.


Assuntos
Animais Domésticos/virologia , Animais Selvagens/virologia , DNA Viral/sangue , Anticorpos Anti-Hepatite B/sangue , Antígenos da Hepatite B/sangue , Hepatite B/veterinária , Animais , Animais Domésticos/sangue , Animais Selvagens/sangue , Biomarcadores/sangue , Brasil/epidemiologia , Hepatite B/sangue , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Reação em Cadeia da Polimerase , Uruguai/epidemiologia
2.
Nat Biotechnol ; 37(2): 160-168, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30718881

RESUMO

Metagenomic sequencing has the potential to transform microbial detection and characterization, but new tools are needed to improve its sensitivity. Here we present CATCH, a computational method to enhance nucleic acid capture for enrichment of diverse microbial taxa. CATCH designs optimal probe sets, with a specified number of oligonucleotides, that achieve full coverage of, and scale well with, known sequence diversity. We focus on applying CATCH to capture viral genomes in complex metagenomic samples. We design, synthesize, and validate multiple probe sets, including one that targets the whole genomes of the 356 viral species known to infect humans. Capture with these probe sets enriches unique viral content on average 18-fold, allowing us to assemble genomes that could not be recovered without enrichment, and accurately preserves within-sample diversity. We also use these probe sets to recover genomes from the 2018 Lassa fever outbreak in Nigeria and to improve detection of uncharacterized viral infections in human and mosquito samples. The results demonstrate that CATCH enables more sensitive and cost-effective metagenomic sequencing.


Assuntos
Biologia Computacional/métodos , Genoma Viral , Metagenoma , Metagenômica , Animais , Culicidae/virologia , Surtos de Doenças , Biblioteca Gênica , Variação Genética , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Febre Lassa/virologia , Nigéria/epidemiologia , Sondas de Oligonucleotídeos , Oligonucleotídeos/genética , Análise de Sequência de DNA , Viroses
3.
Sci Transl Med ; 9(409)2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28954927

RESUMO

The recent Zika virus (ZIKV) outbreak demonstrates that cost-effective clinical diagnostics are urgently needed to detect and distinguish viral infections to improve patient care. Unlike dengue virus (DENV), ZIKV infections during pregnancy correlate with severe birth defects, including microcephaly and neurological disorders. Because ZIKV and DENV are related flaviviruses, their homologous proteins and nucleic acids can cause cross-reactions and false-positive results in molecular, antigenic, and serologic diagnostics. We report the characterization of monoclonal antibody pairs that have been translated into rapid immunochromatography tests to specifically detect the viral nonstructural 1 (NS1) protein antigen and distinguish the four DENV serotypes (DENV1-4) and ZIKV without cross-reaction. To complement visual test analysis and remove user subjectivity in reading test results, we used image processing and data analysis for data capture and test result quantification. Using a 30-µl serum sample, the sensitivity and specificity values of the DENV1-4 tests and the pan-DENV test, which detects all four dengue serotypes, ranged from 0.76 to 1.00. Sensitivity/specificity for the ZIKV rapid test was 0.81/0.86, respectively, using a 150-µl serum input. Serum ZIKV NS1 protein concentrations were about 10-fold lower than corresponding DENV NS1 concentrations in infected patients; moreover, ZIKV NS1 protein was not detected in polymerase chain reaction-positive patient urine samples. Our rapid immunochromatography approach and reagents have immediate application in differential clinical diagnosis of acute ZIKV and DENV cases, and the platform can be applied toward developing rapid antigen diagnostics for emerging viruses.


Assuntos
Antígenos Virais/sangue , Vírus da Dengue/imunologia , Sorogrupo , Zika virus/imunologia , Sequência de Aminoácidos , Anticorpos Monoclonais/imunologia , Antígenos Virais/isolamento & purificação , Cromatografia de Afinidade , Mapeamento de Epitopos , Humanos , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Alinhamento de Sequência
5.
Nature ; 546(7658): 411-415, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28538734

RESUMO

Although the recent Zika virus (ZIKV) epidemic in the Americas and its link to birth defects have attracted a great deal of attention, much remains unknown about ZIKV disease epidemiology and ZIKV evolution, in part owing to a lack of genomic data. Here we address this gap in knowledge by using multiple sequencing approaches to generate 110 ZIKV genomes from clinical and mosquito samples from 10 countries and territories, greatly expanding the observed viral genetic diversity from this outbreak. We analysed the timing and patterns of introductions into distinct geographic regions; our phylogenetic evidence suggests rapid expansion of the outbreak in Brazil and multiple introductions of outbreak strains into Puerto Rico, Honduras, Colombia, other Caribbean islands, and the continental United States. We find that ZIKV circulated undetected in multiple regions for many months before the first locally transmitted cases were confirmed, highlighting the importance of surveillance of viral infections. We identify mutations with possible functional implications for ZIKV biology and pathogenesis, as well as those that might be relevant to the effectiveness of diagnostic tests.


Assuntos
Filogenia , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia , Zika virus/genética , Zika virus/isolamento & purificação , Animais , Brasil/epidemiologia , Colômbia/epidemiologia , Culicidae/virologia , Surtos de Doenças/estatística & dados numéricos , Genoma Viral/genética , Mapeamento Geográfico , Honduras/epidemiologia , Humanos , Metagenoma/genética , Epidemiologia Molecular , Mosquitos Vetores/virologia , Mutação , Vigilância em Saúde Pública , Porto Rico/epidemiologia , Estados Unidos/epidemiologia , Zika virus/classificação , Zika virus/patogenicidade , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/epidemiologia
6.
Eur J Med Chem ; 127: 434-441, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28092859

RESUMO

Zika virus (ZIKV), an emerging Flavivirus, was recently associated with severe neurological complications and congenital diseases. Therefore, development of antiviral agents capable of inhibiting ZIKV replication is urgent. Chloroquine is a molecule with a confirmed safety history for use with pregnant women, and has been found to exhibit anti-ZIKV activity at concentrations around 10 µM. This suggests that modifications to the chloroquine structure could be promising for obtaining more effective anti-ZIKV agents. Here, we report the ability of a series of N-(2-(arylmethylimino)ethyl)-7-chloroquinolin-4-amine derivatives to inhibit ZIKV replication in vitro. We have found that the quinoline derivative, N-(2-((5-nitrofuran-2-yl)methylimino)ethyl)-7-chloroquinolin-4-amine, 40, was the most potent compound within this series, reducing ZIKV replication by 72% at 10 µM. Compound 40 exhibits an EC50 value of 0.8 ± 0.07 µM, compared to that of chloroquine of 12 ± 3.2 µM. Good activities were also obtained for other compounds, including those with aryl groups = phenyl, 4-fluorophenyl, 4-nitrophenyl, 2,6-dimethoxyphenyl, 3-pyridinyl and 5-nitrothien-2-yl. Syntheses of these quinoline derivatives have been obtained both by thermal and ultrasonic means. The ultrasonic method produced comparable yields to the thermal (reflux) method in very much shorter times 30-180 s compared to 30-180 min reactions times. These results indicate that this group of compounds is a good follow-up point for the potential discovery of new drugs against the Zika disease.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Cloroquina/síntese química , Cloroquina/farmacologia , Temperatura , Ondas Ultrassônicas , Zika virus/efeitos dos fármacos , Animais , Antivirais/química , Chlorocebus aethiops , Cloroquina/química , Cloroquina/toxicidade , Células Vero , Replicação Viral/efeitos dos fármacos , Zika virus/fisiologia
7.
Eur J Med Chem ; 127: 334-340, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28068604

RESUMO

Zika virus (ZIKV), an arthropod-born Flavivirus, has been associated with a wide range of neurological diseases in adults, foetuses and neonates. Since no vaccine is available, repurposing of antiviral drugs currently in medical use is necessary. Mefloquine has confirmed anti-ZIKV activity. We used medicinal chemistry-driven approaches to synthesize and evaluate the ability of a series of new 2,8-bis(trifluoromethyl)quinoline derivatives to inhibit ZIKV replication in vitro, in order to improve the potency of mefloquine. We found that quinoline derivatives 3a and 4 were the most potent compounds within this series, both with mean EC50 values of 0.8 µM, which represents a potency 5 times that of mefloquine. These results indicate that new 2,8-bis(trifluoromethyl)quinoline chemical structures may be promising for the development of novel anti-ZIKV drugs.


Assuntos
Antivirais/química , Antivirais/farmacologia , Mefloquina/farmacologia , Quinolinas/química , Quinolinas/farmacologia , Zika virus/efeitos dos fármacos , Animais , Antivirais/síntese química , Antivirais/toxicidade , Chlorocebus aethiops , Desenho de Fármacos , Quinolinas/síntese química , Quinolinas/toxicidade , Relação Estrutura-Atividade , Células Vero , Replicação Viral/efeitos dos fármacos , Zika virus/fisiologia
9.
Ann Agric Environ Med ; 22(1): 11-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25780820

RESUMO

INTRODUCTION AND OBJECTIVE: Recently, investigations in a swine herd identified evidence of the existence of a novel member of the Hepadnavirus family endemic in swine. The aim of this study was to investigate the serological and molecular markers of Hepadnavirus circulation in Brazilian domestic swine and wild boar herds, and to evaluate the identity with HBV and other Hepadnaviruses reported previously. MATERIALS AND METHODS: For the study, 376 swine were screened for hepatitis B virus serological markers. Analyses were performed in serum samples using commercial enzyme-linked immunosorbent assay (ELISA) kits (DiaSorin®) for anti-HBc, HBsAg and anti-HBs. Reactive and undetermined swine serum samples were selected to perform DNA viral extraction (QIAamp DNA Mini Kit, Qiagen®), partial genome amplification and genome sequencing. RESULTS: From 376 swine samples analysed, 28 (7.45%) were reactive to anti-HBc, 3 (0.80%) to HBsAg and 6 (1.6%) to anti-HBs. Besides, more 17 (4.52%) swine samples analyzed were classified in the grey zone of the EIA test to anti-HBc and 2 (0.53%) to HBsAg. From 49 samples molecularly analyzed after serological trial, 4 samples showed a positive result for the qualitative PCR for Hepadnavirus. Phylogenetic reconstruction using partial genome sequencing (360 bp) of 3 samples showed similarity with HBV with 90.8-96.3% of identity. CONCLUSIONS: Serological and molecular data showed evidence of the circulation of a virus similar to hepatitis B virus in swine.


Assuntos
Vírus da Hepatite B/classificação , Vírus da Hepatite B/isolamento & purificação , Hepatite B/veterinária , Doenças dos Suínos/epidemiologia , Animais , Brasil/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Hepatite B/epidemiologia , Hepatite B/virologia , Anticorpos Anti-Hepatite B/análise , Antígenos de Superfície da Hepatite B/análise , Vírus da Hepatite B/genética , Masculino , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/veterinária , Análise de Sequência de DNA/veterinária , Suínos , Doenças dos Suínos/virologia , Proteínas Virais/genética
12.
Nutr Metab (Lond) ; 8(1): 32, 2011 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-21619692

RESUMO

BACKGROUND: Obesity is a chronic disease associated to an inflammatory process resulting in oxidative stress that leads to morpho-functional microvascular damage that could be improved by some dietary interventions. In this study, the intake of Brazil nuts (Bertholletia excelsa), composed of bioactive substances like selenium, α- e γ- tocopherol, folate and polyunsaturated fatty acids, have been investigated on antioxidant capacity, lipid and metabolic profiles and nutritive skin microcirculation in obese adolescents. METHODS: Obese female adolescents (n = 17), 15.4 ± 2.0 years and BMI of 35.6 ± 3.3 kg/m2, were randomized 1:1 in two groups with the diet supplemented either with Brazil nuts [BNG, n = 08, 15-25 g/day (equivalent to 3 to 5 units/day)] or placebo [PG (lactose), n = 09, one capsule/day] and followed for 16 weeks. Anthropometry, metabolic-lipid profiles, oxidative stress and morphological (capillary diameters) and functional [functional capillary density, red blood cell velocity (RBCV) at baseline and peak (RBCVmax) and time (TRBCVmax) to reach it during post-occlusive reactive hyperemia, after 1 min arterial occlusion] microvascular variables were assessed by nailfold videocapillaroscopy at baseline (T0) and after intervention (T1). RESULTS: T0 characteristics were similar between groups. At T1, BNG (intra-group variation) had increased selenium levels (p = 0.02), RBCV (p = 0.03) and RBCVmax (p = 0.03) and reduced total (TC) (p = 0.02) and LDL-cholesterol (p = 0.02). Compared to PG, Brazil nuts intake reduced TC (p = 0.003), triglycerides (p = 0.05) and LDL-ox (p = 0.02) and increased RBCV (p = 0.03). CONCLUSION: Brazil nuts intake improved the lipid profile and microvascular function in obese adolescents, possibly due to its high level of unsaturated fatty acids and bioactive substances. TRIAL REGISTRATION: Clinical Trials.gov NCT00937599.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...