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1.
Biologicals ; 80: 43-52, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36175304

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), first identified in Wuhan, China, is the causative agent of the coronavirus disease 2019 (COVID-19). Since its first notification in São Paulo state (SP) on 26th February 2020, more than 22,300,000 cases and 619,000 deaths were reported in Brazil. In early pandemic, SARS-CoV-2 spread locally, however, over time, this virus was disseminated to other regions of the country. Herein, we performed genomic sequencing and phylogenetic analysis of SARS-CoV-2 using 20 clinical samples of COVID-19 confirmed cases from 9 cities of Minas Gerais state (MG), in order to evaluate the molecular properties of circulating viral strains in this locality from March to May 2020. Our analyses demonstrated the circulation of B.1 lineage isolates in the investigated locations and nucleotide substitutions were observed into the genomic regions related to important viral structures. Additionally, sequences generated in this study clustered with isolates from SP, suggesting a dissemination route between these two states. Alternatively, monophyletic groups of sequences from MG and other states or country were observed, indicating independent events of virus introduction. These results reinforce the need of genomic surveillance for understand the ongoing spread of emerging viral pathogens.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Filogenia , Brasil/epidemiologia , Genoma Viral/genética
2.
J Thromb Thrombolysis ; 47(1): 162-164, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30353451

RESUMO

Severe life-threatening thromboembolism may be caused exclusively by the presence of an acute CMV infection or due to the association of this agent and other thrombogenic factors. We report a case of an immunocompetent young female patient who presented a pulmonary embolism associated with acute CMV infection. The patient did not have any other apparent cause of thrombosis. She was successfully treated with rivaroxaban for 6 months without further episodes. To the best of our knowledge, this is the first report of a pulmonary embolism associated with CMV treated with a direct oral anticoagulant. The current case report calls attention to the importance of signs and symptoms of thromboembolism among patients with CMV. Direct oral anticoagulants can potentially bring the same benefits to treat pulmonary embolism associated with CMV as those observed in patients not infected.


Assuntos
Infecções por Citomegalovirus/complicações , Embolia Pulmonar/complicações , Rivaroxabana/uso terapêutico , Inibidores do Fator Xa/uso terapêutico , Feminino , Humanos , Embolia Pulmonar/tratamento farmacológico , Embolia Pulmonar/virologia
3.
Science ; 372(6544): 815-821, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-33853970

RESUMO

Cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Manaus, Brazil, resurged in late 2020 despite previously high levels of infection. Genome sequencing of viruses sampled in Manaus between November 2020 and January 2021 revealed the emergence and circulation of a novel SARS-CoV-2 variant of concern. Lineage P.1 acquired 17 mutations, including a trio in the spike protein (K417T, E484K, and N501Y) associated with increased binding to the human ACE2 (angiotensin-converting enzyme 2) receptor. Molecular clock analysis shows that P.1 emergence occurred around mid-November 2020 and was preceded by a period of faster molecular evolution. Using a two-category dynamical model that integrates genomic and mortality data, we estimate that P.1 may be 1.7- to 2.4-fold more transmissible and that previous (non-P.1) infection provides 54 to 79% of the protection against infection with P.1 that it provides against non-P.1 lineages. Enhanced global genomic surveillance of variants of concern, which may exhibit increased transmissibility and/or immune evasion, is critical to accelerate pandemic responsiveness.


Assuntos
COVID-19/epidemiologia , COVID-19/virologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/virologia , SARS-CoV-2/classificação , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Brasil/epidemiologia , Monitoramento Epidemiológico , Genoma Viral , Genômica , Humanos , Modelos Teóricos , Epidemiologia Molecular , Mutação , Ligação Proteica , SARS-CoV-2/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/metabolismo , Carga Viral
4.
Lancet Microbe ; 2(10): e527-e535, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34258603

RESUMO

BACKGROUND: Mutations accrued by SARS-CoV-2 lineage P.1-first detected in Brazil in early January, 2021-include amino acid changes in the receptor-binding domain of the viral spike protein that also are reported in other variants of concern, including B.1.1.7 and B.1.351. We aimed to investigate whether isolates of wild-type P.1 lineage SARS-CoV-2 can escape from neutralising antibodies generated by a polyclonal immune response. METHODS: We did an immunological study to assess the neutralising effects of antibodies on lineage P.1 and lineage B isolates of SARS-CoV-2, using plasma samples from patients previously infected with or vaccinated against SARS-CoV-2. Two specimens (P.1/28 and P.1/30) containing SARS-CoV-2 lineage P.1 (as confirmed by viral genome sequencing) were obtained from nasopharyngeal and bronchoalveolar lavage samples collected from patients in Manaus, Brazil, and compared against an isolate of SARS-CoV-2 lineage B (SARS.CoV2/SP02.2020) recovered from a patient in Brazil in February, 2020. Isolates were incubated with plasma samples from 21 blood donors who had previously had COVID-19 and from a total of 53 recipients of the chemically inactivated SARS-CoV-2 vaccine CoronaVac: 18 individuals after receipt of a single dose and an additional 20 individuals (38 in total) after receipt of two doses (collected 17-38 days after the most recent dose); and 15 individuals who received two doses during the phase 3 trial of the vaccine (collected 134-230 days after the second dose). Antibody neutralisation of P.1/28, P.1/30, and B isolates by plasma samples were compared in terms of median virus neutralisation titre (VNT50, defined as the reciprocal value of the sample dilution that showed 50% protection against cytopathic effects). FINDINGS: In terms of VNT50, plasma from individuals previously infected with SARS-CoV-2 had an 8·6 times lower neutralising capacity against the P.1 isolates (median VNT50 30 [IQR <20-45] for P.1/28 and 30 [<20-40] for P.1/30) than against the lineage B isolate (260 [160-400]), with a binominal model showing significant reductions in lineage P.1 isolates compared with the lineage B isolate (p≤0·0001). Efficient neutralisation of P.1 isolates was not seen with plasma samples collected from individuals vaccinated with a first dose of CoronaVac 20-23 days earlier (VNT50s below the limit of detection [<20] for most plasma samples), a second dose 17-38 days earlier (median VNT50 24 [IQR <20-25] for P.1/28 and 28 [<20-25] for P.1/30), or a second dose 134-260 days earlier (all VNT50s below limit of detection). Median VNT50s against the lineage B isolate were 20 (IQR 20-30) after a first dose of CoronaVac 20-23 days earlier, 75 (<20-263) after a second dose 17-38 days earlier, and 20 (<20-30) after a second dose 134-260 days earlier. In plasma collected 17-38 days after a second dose of CoronaVac, neutralising capacity against both P.1 isolates was significantly decreased (p=0·0051 for P.1/28 and p=0·0336 for P.1/30) compared with that against the lineage B isolate. All data were corroborated by results obtained through plaque reduction neutralisation tests. INTERPRETATION: SARS-CoV-2 lineage P.1 might escape neutralisation by antibodies generated in response to polyclonal stimulation against previously circulating variants of SARS-CoV-2. Continuous genomic surveillance of SARS-CoV-2 combined with antibody neutralisation assays could help to guide national immunisation programmes. FUNDING: São Paulo Research Foundation, Brazilian Ministry of Science, Technology and Innovation and Funding Authority for Studies, Medical Research Council, National Council for Scientific and Technological Development, National Institutes of Health. TRANSLATION: For the Portuguese translation of the abstract see Supplementary Materials section.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Antivirais , Brasil/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , SARS-CoV-2/genética , Estados Unidos , Vacinação
5.
medRxiv ; 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33688664

RESUMO

Cases of SARS-CoV-2 infection in Manaus, Brazil, resurged in late 2020, despite high levels of previous infection there. Through genome sequencing of viruses sampled in Manaus between November 2020 and January 2021, we identified the emergence and circulation of a novel SARS-CoV-2 variant of concern, lineage P.1, that acquired 17 mutations, including a trio in the spike protein (K417T, E484K and N501Y) associated with increased binding to the human ACE2 receptor. Molecular clock analysis shows that P.1 emergence occurred around early November 2020 and was preceded by a period of faster molecular evolution. Using a two-category dynamical model that integrates genomic and mortality data, we estimate that P.1 may be 1.4-2.2 times more transmissible and 25-61% more likely to evade protective immunity elicited by previous infection with non-P.1 lineages. Enhanced global genomic surveillance of variants of concern, which may exhibit increased transmissibility and/or immune evasion, is critical to accelerate pandemic responsiveness.

6.
Science ; 369(6508): 1255-1260, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32703910

RESUMO

Brazil currently has one of the fastest-growing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemics in the world. Because of limited available data, assessments of the impact of nonpharmaceutical interventions (NPIs) on this virus spread remain challenging. Using a mobility-driven transmission model, we show that NPIs reduced the reproduction number from >3 to 1 to 1.6 in São Paulo and Rio de Janeiro. Sequencing of 427 new genomes and analysis of a geographically representative genomic dataset identified >100 international virus introductions in Brazil. We estimate that most (76%) of the Brazilian strains fell in three clades that were introduced from Europe between 22 February and 11 March 2020. During the early epidemic phase, we found that SARS-CoV-2 spread mostly locally and within state borders. After this period, despite sharp decreases in air travel, we estimated multiple exportations from large urban centers that coincided with a 25% increase in average traveled distances in national flights. This study sheds new light on the epidemic transmission and evolutionary trajectories of SARS-CoV-2 lineages in Brazil and provides evidence that current interventions remain insufficient to keep virus transmission under control in this country.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Número Básico de Reprodução , Teorema de Bayes , Betacoronavirus/classificação , Brasil/epidemiologia , COVID-19 , Teste para COVID-19 , Cidades/epidemiologia , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Europa (Continente) , Evolução Molecular , Genoma Viral , Humanos , Modelos Genéticos , Modelos Estatísticos , Pandemias/prevenção & controle , Filogenia , Filogeografia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/virologia , SARS-CoV-2 , Análise Espaço-Temporal , Viagem , População Urbana
7.
Ann Hepatol ; 8(4): 339-45, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20009133

RESUMO

Serum hepatitis B virus (HBV) DNA level is a predictor of the development of cirrhosis and hepatocellular carcinoma in chronic hepatitis B patients. Nevertheless, the distribution of viral load levels in chronic HBV patients in Brazil has yet to be described. This cross-sectional study included 564 participants selected in nine Brazilian cities located in four of the five regions of the country using the database of a medical diagnostics company. Admission criteria included hepatitis B surface antigen seropositivity, availability of HBV viral load samples and age >or=18 years. Males comprised 64.5% of the study population. Mean age was 43.7 years. Most individuals (62.1%) were seronegative for the hepatitis B e antigen (HBeAg). Median serum ALT level was 34 U/L. In 58.5% of the patients HBV-DNA levels ranged from 300 to 99,999 copies/mL; however, in 21.6% levels were undetectable. Median HBV-DNA level was 2,351 copies/mL. Over 60% of the patients who tested negative for HBeAg and in whom ALT level was less than 1.5 times the upper limit of the normal range had HBV-DNA levels > 2,000 IU/mL, which has been considered a cut-off point for indicating a liver biopsy and/or treatment. In conclusion, HBV-DNA level identified a significant proportion of Brazilian individuals with chronic hepatitis B at risk of disease progression. Furthermore, this tool enables those individuals with high HBV-DNA levels who are susceptible to disease progression to be identified among patients with normal or slightly elevated ALT.


Assuntos
Alanina Transaminase/sangue , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Carga Viral , Adulto , Biópsia , Brasil/epidemiologia , Estudos Transversais , DNA Viral/sangue , Progressão da Doença , Feminino , Vírus da Hepatite B/genética , Hepatite B Crônica/epidemiologia , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade
8.
J Nephrol ; 20(5): 609-16, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17918148

RESUMO

BACKGROUND: At present it is not clearly established if hepatitis C virus (HCV)-RNA levels and genotype distribution have any peculiar aspect in HCV-infected end-stage renal disease (ESRD) patients. The aim of this study was to evaluate in HCV-infected ESRD patients, the alanine aminotransferase (ALT) profile, HCV-RNA levels and genotype distribution, comparing them with HCV-infected patients with normal renal function. METHODS: A cross-sectional study was performed in 66 hemodialysis patients (group 1) and 264 subjects with normal renal function (group 2). All participants in both groups had detectable HCV-RNA. Mean ALT levels were determined in all subjects as well the viral load and the genotype. RESULTS: Groups were similar according to gender and age. ALT was normal in 74% patients in group 1 and in 23% in group 2 (p<0.001). The median viral load was 5.3 x 10(5) IU/mL in group 1 and 6.6 x 10(5) IU/mL in group 2 (p=0.23). Genotype 1b was the most prevalent in both groups (56% vs. 57%; p=0.38). CONCLUSION: HCV-infected ESRD patients have lower ALT levels, but the viral load and the genotype distribution are similar to those observed in HCV-infected individuals with normal renal function.


Assuntos
Alanina Transaminase/sangue , Hepacivirus/genética , Hepatite C/genética , Falência Renal Crônica/virologia , Rim/virologia , RNA Viral , Diálise Renal , Carga Viral , Adulto , Brasil , Estudos Transversais , Feminino , Genótipo , Hepatite C/enzimologia , Humanos , Rim/enzimologia , Falência Renal Crônica/enzimologia , Falência Renal Crônica/genética , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade
9.
Pediatr Pulmonol ; 52(10): 1300-1305, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28771972

RESUMO

BACKGROUND: As of 2013, fewer than 20% of patients in the Brazilian CF Registry had two CFTR mutations identified. The aim of this study was to sequence the coding region of the CFTR in Brazilian CF patients and determine the frequency of mutations in this cohort. METHODS: Patients with CF and those with suspected atypical CF or CFTR-related disorders were invited to enroll. Total DNA was extracted from blood samples, quantified, and purified. Library preparation was performed using Ion Xpress™ Plus gDNA and Amplicon Library preparation kits (Life Technologies), as well as sequencing using the Ion Torrent platform (Life Technologies). RESULTS: A total of 141 patients were enrolled, and 45 mutations were identified. Among 126 CF patients, we identified mutations in 97.2% of alleles. The three most common mutations were F508del, G542X, and 3120 + 1G->A. Five novel pathogenic mutations were also identified. CONCLUSIONS: Next generation sequencing (NGS) allowed the identification of mutations in most CF alleles and confirmed allelic heterogeneity in our population.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Adolescente , Alelos , Brasil/epidemiologia , Criança , Fibrose Cística/epidemiologia , Feminino , Frequência do Gene , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Mutação
10.
PLoS One ; 10(5): e0125460, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25955572

RESUMO

BACKGROUND: The aim of this study was to evaluate the OpenArray platform for genetic testing of blood donors and to assess the genotype frequencies of nucleotide-polymorphisms (SNPs) associated with venous thrombosis (G1691A and G20210A), hyperhomocysteinemia (C677T, A1298C), and hereditary hemochromatosis (C282Y, H63D and S65C) in blood donors from Sao Paulo, Brazil. METHODS: We examined 400 blood donor samples collected from October to November 2011. The SNPs were detected using OpenArray technology. The blood samples were also examined using a real-time PCR-FRET system to compare the results and determine the accuracy of the OpenArray method. RESULTS: We observed 100% agreement in all assays tested, except HFE C282Y, which showed 99.75% agreement. The HFE C282Y assay was further confirmed through direct sequencing, and the results showed that OpenArray analysis was accurate. The calculated frequencies of each SNP were FV G1691A 98.8% (G/G), 1.2% (G/A); FII G2021A 99.5% (G/G), 0.5% (G/A); MTHFR C677T 45.5% (C/C), 44.8% (C/T), 9.8% (T/T); MTHFR A1298C 60.3% (A/A), 33.6% (A/C), 6.1% (C/C); HFE C282Y 96%(G/G), 4%(G/A), HFE H63D 78.1%(C/C), 20.3% (C/G), 1.6% (G/G); and HFE S65C 98.1% (A/A), 1.9% (A/T). CONCLUSION: Taken together, these results describe the frequencies of SNPs associated with diseases and are important to enhance our current knowledge of the genetic profiles of Brazilian blood donors, although a larger study is needed for a more accurate determination of the frequency of the alleles. Furthermore, the OpenArray platform showed a high concordance rate with standard FRET RT-PCR.


Assuntos
Doadores de Sangue , Hemocromatose/genética , Hiper-Homocisteinemia/genética , Polimorfismo de Nucleotídeo Único , Trombose Venosa/genética , Adulto , Alelos , Brasil , Fator V/genética , Feminino , Expressão Gênica , Frequência do Gene , Testes Genéticos , Genótipo , Hemocromatose/diagnóstico , Proteína da Hemocromatose , Ensaios de Triagem em Larga Escala , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Hiper-Homocisteinemia/diagnóstico , Masculino , Proteínas de Membrana/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Protrombina/genética , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Trombose Venosa/diagnóstico
12.
Rev. bras. reumatol ; 28(6): 179-81, nov.-dez. 1988.
Artigo em Português | LILACS | ID: lil-72793

RESUMO

Grande número de drogas tem sido responsabilizado pela induçäo de auto-anticorpos; algumas dessas drogas säo capazes de induzir quadro clínico de LES, embora geralmente sem envolvimento renal ou de sistema nervoso. Os autores investigam a freqüência de induçäo de lúpus pela isoniazida em 20 portadores de tuberculose após três a seis meses da introduçäo dessa medicaçäo. Nenhum paciente apresentou quadro clínico sugestivo de lúpus após introduçäo da isoniazida e apenas três pacientes (15%) mostraram positividade do FAN. A freqüência dos anticorpos anti-histona e antiDNA desnaturado foi maior após inicio da terapêutica. Esses dados sugerem que o uso de isoniazida näo estaria associado à induçäo de lúpus clínico, embora essa droga seja capaz de induzir o aparecimento de anticorpos antinucleares


Assuntos
Humanos , Masculino , Feminino , DNA/imunologia , Isoniazida/efeitos adversos , Lúpus Eritematoso Sistêmico/induzido quimicamente , Anticorpos/imunologia , Técnicas Imunológicas , Tuberculose/tratamento farmacológico
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