Navegando por Autor "DEMACHKI, Sâmia"

Agora exibindo 1 - 3 de 3

Acesso aberto (Open Access)
Association of killer cell immunoglobulin-like receptor polymorphisms with chronic hepatitis C and responses to therapy in Brazil
(2013) VASCONCELOS, Janaina Mota de; MÓIA, Lizomar de Jesus Maués Pereira; AMARAL, Ivanete do Socorro Abraçado; MIRANDA, Esther Castello Branco Mello; TAKESHITA, Louise Yukari; OLIVEIRA, Layanna Freitas de; MENDES, Lilian de Araújo Melo; SASTRE, Danuta; TAMEGÃO-LOPES, Bruna Pedroso; PEDROZA, Larysse Santa Rosa de Aquino; SANTOS, Sidney Emanuel Batista dos; SOARES, Manoel do Carmo Pereira; ARAÚJO, Marialva Tereza Ferreira de; BANDEIRA, Camila Lucas; SILVA, Adriana Maria Paixão de Sousa da; MEDEIROS, Zilene Lameira de; SENA, Leonardo dos Santos; DEMACHKI, Sâmia; SANTOS, Eduardo José Melo dos
Soroprevalence for Hepatitis C virus is reported as 2.12% in Northern Brazil, with about 50% of the patients exhibiting a sustained virological response (SVR). Aiming to associate polymorphisms in Killer Cell Immunoglobulin-like Receptors (KIR) with chronic hepatitis C and therapy responses we investigated 125 chronic patients and 345 controls. Additionally, 48 ancestry markers were genotyped to control for population stratification. The frequency of the KIR2DL2 and KIR2DL2+HLA-CAsp80 gene and ligand was higher in chronic infected patients than in controls (p < 0.0009, OR = 3.4; p = 0.001, OR = 3.45). In fact, KIR2DL3 is a weaker inhibitor of NK activity than KIR2DL2, which could explain the association of KIR2DL2 with chronic infection. Moreover, KIR2DS2 and KIR2DS2+HLA-CAsp80 (p < 0.0001, OR = 2.51; p = 0.0084, OR = 2.62) and KIR2DS3 (p < 0.0001; OR = 2.57) were associated with chronic infection, independently from KIR2DL2. No differences in ancestry composition were observed between control and patients, even with respect to therapy response groups. The allelic profile KIR2DL2/KIR2DS2/KIR2DS3 was associated with the chronic hepatitis C (p < 0.0001; OR = 3). Furthermore, the patients also showed a higher mean number of activating genes and a lower frequency of the homozygous AA profile, which is likely secondary to the association with non-AA and/or activating genes. In addition, the KIR2DS5 allele was associated with SVR (p = 0.0261; OR = 0.184).The ancestry analysis of samples ruled out any effects of population substructuring and did not evidence interethnic differences in therapy response, as suggested in previous studies.
Acesso aberto (Open Access)
Clinical and pathological importance of vacA allele heterogeneity and cagA status in peptic ulcer disease in patients from North Brazil
(2005-12) MARTINS, Luisa Caricio; CORVELO, Tereza Cristina de Oliveira; DEMACHKI, Sâmia; ARAÚJO, Marialva Tereza Ferreira de; ASSUMPÇÃO, Mônica Baraúna de; VILAR, Simone Cristina Araujo Jucá; FREITAS, Felipe Bonfim; BARBOSA, Hivana Patricia Melo; FECURY, Amanda Alves; AMARAL, Renata Kelly Costa do; SANTOS, Sidney Emanuel Batista dos
We have examined the prevalence of gene cagA and vacA alleles in 129 patients, 69 with gastritis and 60 with peptic ulcer diseases from North Brazil and their relation with histopathological data. vacA and cagA genotype were determined by polymerase chain reaction. Hematoxylin-eosin staining was used for histological diagnosis. 96.6% of the patients were colonized by Helicobacter pylori strains harboring single vacA genotype (nont-mixed infection). Among them, 11.8% had subtype s1a, 67.8% had subtype s1b, and 17% subtype s2. In regard to the middle region analysis, m1 alleles were found in 75.4% and m2 in 21.2% of patients. The cagA gene was detected in 78% patients infected with H. pylori and was associated with the s1-m1 vacA genotype. The H. pylori strains, vacA s1b m1/cagA-positive, were associated with increased risk of peptic ulcer disease and higher amounts of lymphocytic and neutrophilic infiltrates and the presence of intestinal metaplasia. These findings show that cagA and vacA genotyping may have clinical relevance in Brazil.
Acesso aberto (Open Access)
Toll-like receptor 3 gene polymorphisms are not associated with the risk of hepatitis B and hepatitis C virus infection
(Universidade Federal do Pará, 2015-04) SÁ, Keyla Santos Guedes de; PIRES NETO, Orlando de Souza; SANTANA, Bárbara Brasil; GOMES, Samara Tatielle Monteiro; AMORAS, Ednelza da Silva Graça; CONDE, Simone Regina Souza da Silva; DEMACHKI, Sâmia; AZEVEDO, Vânia Nakauth; MACHADO, Luiz Fernando Almeida; FEITOSA, Rosimar Neris Martins; ISHAK, Marluísa de Oliveira Guimarães; ISHAK, Ricardo; VALLINOTO, Antonio Carlos Rosário
Introduction: The present study investigated the prevalence of two single-nucleotide polymorphisms (SNPs) in the Toll-like receptor 3 (TLR3) gene in patients infected with hepatitis B virus (HBV) and hepatitis C virus (HCV). Methods: Samples collected from HCV (n = 74) and HBV (n = 35) carriers were subjected to quantitative real-time PCR (qPCR) to detect the presence of the SNPs rs5743305 and rs3775291 in TLR3 and to measure the following biomarkers: alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), and prothrombin time (PT). A healthy control group was investigated and consisted of 299 HCV- and HBV-seronegative individuals. Results: No signifi cant differences in allele, genotype and haplotype frequencies were observed between the investigated groups, and no association was observed between the polymorphisms and histopathological results. Nevertheless, genotypes TA/AA (rs5743305) and GG (rs3775291) appear to be associated with higher levels of ALT (p<0.01), AST (p<0.05) and PT (p<0.05). In addition, genotypes TT (rs5743305; p<0.05) and GG (rs3775291; p<0.05) were associated with higher GGT levels. Conclusions: This genetic analysis revealed the absence of an association between the polymorphisms investigated and susceptibility to HBV and HCV infection; however, these polymorphisms might be associated with a greater degree of biliary damage during the course of HCV infection.