ARIANA CAROLINA FERREIRA
Projetos de Pesquisa
Unidades Organizacionais
LIM/07 - Laboratório de Gastroenterologia Clínica e Experimental, Hospital das Clínicas, Faculdade de Medicina
4 resultados
Resultados de Busca
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conferenceObject HBV resistance frequency in nucleos(t)ide analogue-untreated patients from different Brazilian regions(2012) GOMES-GOUVEA, Michele S.; MENDES-CORREA, Maria Cassia; FERREIRA, Ariana C.; TEIXEIRA, Rosangela; ANDRADE, Jose R.; BARROS, Lena Maria F.; FERREIRA, Adalgisa S.; REZENDE, Rosamar F.; NASTRI, Ana Catharina S.; LEITE, Andrea G.; PICCOLI, Leonora Z.; GALVAN, Josiane; CONDE, Simone Regina S.; SOARES, Manoel C.; CARRILHO, Flair J.; PINHO, Joao R.Background - Presence of viral variants with drug-resistance mutations in drug-naïve hepatitis B virus (HBV) infected patients can seriously compromise response to antiviral treatment. Therefore, our study aimed to determine the prevalence of HBV with drug-resistance in 557 untreated chronic hepatitis B (CHB) patients with nucleos(t)ide analogues (NA) from five different geographic regions of Brazil. Methods – HBV reverse-tran-scriptase (RT) region was sequenced and mutations associated with resistance to NA inhibitors were analyzed. Amino acid changes potentially associated with resistance were also investigated. Furthermore, HBV genotypes and subgenotypes were determined by phylogenetic analysis of the sequences. Results – HBV genotypes A [A1 (66.8%), A2 (2.3%)] and D [D1 (0.5%), D2 (4.3%), D3 (11.8%), D4 (6.6%)] were the most prevalent in Brazil, but genotypes B1 (0.2%), B2 (0.2%), C2 (0.7%), E (0.7%), F2a (4.5%), F4 (0.4%) and G (0.5%) were also found. Overall, 1.8% (10/557) of the patients carried HBV variants with primary drug-resistance mutations [rtM204V/I (0.4%); rtM204V + rtS202G (0.4%); rtA181S/T (0.4%); rtM250I (0.2%); rtA194T (0.4%)]. The four strains with mutation at position 204 also had compensatory mutations [rtL180M (3/4); rtL180M + rtV207I (1/4). One patient was infected with HBV variant only with compensatory mutations (rtV173L + rtL180M). Thirty (5%) patients were infected with strain harboring some of that mutation potentially associated with Adefovir resistance [rtS85A (n=1), rtV214A (n=6), rtQ215S (n=14), rtI233V (n=6), rtN238T (n=4), rtN238D (n=5)]. Additionally, we observed in 18 (3.2%) patients the presence of variants with novel amino acid substitutions at positions reported to be potentially associated with Adefovir resistance: rtV214G (n=2), V214E (n=1), Q215H (n=6), Q215P (n=1), E218D (n=2), I233L (n=1), T237A (n=1), N238H (n=3), N238A (n=1). Conclusions – HBV variability is high in Brazil, thirteen HBV subgenotypes were found. The rate of important drug resistance mutations was low (1.8%) among the drug-naïve HBV infected patients studied, indicating the high potential to full efficacy of nucleos(t)ide analogue therapy in these patients. The high frequency of mutations potentially associated with Adefovir resistance among untreated patients suggests that these mutations are not really associated to resistance.conferenceObject Evidence of Hepatitis E Virus Infection in Liver Transplant Recipients from Brazil(2013) GOMES-GOUVEA, Michele S.; FERREIRA, Ariana C.; FEITOZA, Bruna; PESSOA, Mario G.; ABDALA, Edson; TERRABUIO, Deborah R.; MORAES, Adriano C.; BONAZZI, Patricia R.; D'ALBUQUERQUE, Luiz C.; CARRILHO, Flair J.; PINHO, Joao R.- Serological and molecular markers of hepatitis E virus infection in HIV-infected patients in Brazil(2018) FERREIRA, A. C.; GOMES-GOUVEA, Michele Soares; LISBOA-NETO, G.; MENDES-CORREA, M. C. J.; PICONE, C. M.; SALLES, N. A.; MENDRONE-JUNIOR, A.; CARRILHO, F. J.; PINHO, J. R. R.In Brazil, the circulation of hepatitis E virus (HEV) has been demonstrated in distinct groups of individuals and some animals, but its prevalence among individuals with human immunodeficiency virus (HIV) infection is unknown. This study aimed to assess the frequency of serological and molecular HEV markers in individuals infected with HIV from So Paulo, Brazil. Serum and plasma samples of 354 HIV-infected patients collected between 2007 and 2013 were included. All samples were tested for anti-HEV IgG and IgM antibodies and HEV RNA. Anti-HEV IgG and IgM antibodies were detected in 10.7% (38/354) and 1.4% (5/354) of the samples, respectively. Both antibodies were detected simultaneously in only two samples. HEV RNA was not detected in any sample. There was no significant correlation of anti-HEV serological status (positivity to anti-HEV IgG and/or IgM) with sex, age, CD4(+) T cell count, HIV viral load, antiretroviral therapy, liver enzyme levels, or coinfection with hepatitis B virus and/or hepatitis C virus. Our study provides serological evidence of past and recent HEV infections in HIV-infected patients from So Paulo, Brazil. However, the occurrence of ongoing HEV infection appears be a rare event in this population.
- HBV carrying drug-resistance mutations in chronically infected treatment-naive patients(2015) GOMES-GOUVEA, Michele S.; FERREIRA, Ariana C.; TEIXEIRA, Rosangela; ANDRADE, Jose R.; FERREIRA, Adalgisa S. P.; BARROS, Lena M. F.; REZENDE, Rosamar E. F.; NASTRI, Ana C. S. Santos; LEITE, Andrea G. B.; PICCOLI, Leonora Z.; GALVAN, Josiane; CONDE, Simone R. S. S.; SOARES, Manoel C. P.; KLIEMANN, Dimas A.; BERTOLINI, Dennis A.; KUNYOSHI, Aline S. O.; LYRA, Andre C.; OIKAWA, Marcio K.; ARAUJO, Luciano V. de; CARRILHO, Flair J.; MENDES-CORREA, Maria C. J.; PINHO, Joao R. RebelloBackground: Nucleoside/nucleotide analogue (NA) treatment causes selection pressure for HBV strains carrying mutations conferring NA resistance. Drug-resistance mutations occur in the reverse transcriptase (RT) region of the HBV polymerase gene and spontaneously arise during viral replication. These mutations can also alter the hepatitis B surface (HBs) protein and in some cases reduce binding to HBs antibodies. The spread of NA-resistant HBV may impact the efficacy of antiviral treatment and hepatitis B immunization programmes. In this study, we used direct sequencing to assess the occurrence of HBV carrying known mutations that confer NA resistance in the largest cohort of treatment-naive patients with chronic hepatitis B (CHB) to date. Methods: HBV DNA samples isolated from 702 patients were sequenced and the RT region subjected to mutational analysis. Results: There was high genetic variability among the HBV samples analysed: A1 (63.7%), D3 (14.5%), A2 (3.3%), A3 (0.1%), B1 (0.1%), B2 (0.1%), C2 (0.9%), D1 (0.9%), D2 (4.6%), D4 (5.1%), D unclassified sub-genotype (0.7%), E (0.6%), F2a (4.6%), F4 (0.4%) and G (0.4%). HBV strains harbouring mutations conferring NA resistance alone or combined with compensatory mutations were identified in 1.6% (11/702) of the patients. Conclusions: HBV strains harbouring resistance mutations can comprise the major population of HBV quasispecies in treatment-naive patients. In Brazil, there is a very low frequency of untreated patients who are infected with these strains. These findings suggest that the spread and natural selection of drug-resistant HBV is an uncommon event and/or most of these strains remain unstable in the absence of NA selective pressure.