Navegando por Autor "MACHADO, Luiz Fernando Almeida"

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Caracterização molecular do Htlv-1 em pacientes com paraparesia espástica tropical/mielopatia associada ao HTLV-1 em Belém, Pará
(2006-10) SOUZA, Lucinda Assunção Gustavo; LOPES, Ivina Giselle Lima; MAIA, Eduardo Leitão; AZEVEDO, Vânia Nakauth; MACHADO, Luiz Fernando Almeida; ISHAK, Marluísa de Oliveira Guimarães; ISHAK, Ricardo; VALLINOTO, Antonio Carlos Rosário
The present study evaluated the occurrence of HTLV-1 and its subtypes in blood samples of patients presenting symptoms of tropical spastic paraparesis/HTLV-1 associated myelopathy. The detection of HTLV infection was performed by serological and molecular assays. Five patients were infected by HTLV-1 of the Cosmopolitan subtype, subgroup Transcontinental. The results confirm the occurrence of HTLV-1 infection among patients with clinical diagnosis of tropical spastic paraparesis/HTLV-1 associated myelopathy in Belém, Pará.
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Caracterização molecular do HTLV-1/2 em doadores de sangue em Belém, Estado do Pará: primeira descrição do subtipo HTLV-2b na região Amazônica
(2009-06) SANTOS, Ethienne Lobato dos; TAMEGÃO-LOPES, Bruna Pedroso; MACHADO, Luiz Fernando Almeida; ISHAK, Marluísa de Oliveira Guimarães; ISHAK, Ricardo; LEMOS, José Alexandre Rodrigues de; VALLINOTO, Antonio Carlos Rosário
This study aimed to perform molecular characterization on the human T-cell lymphotropic virus (HTLV) infecting blood donors attended at the Hematology and Hemotherapy Center-Foundation of Pará. DNA samples from 79 HTLV-seropositive individuals were analyzed by means of the polymerase chain reaction on the pX, env and 5'LTR genomic regions; restriction fragment length polymorphism analysis; and sequencing of the 5'LTR region with subsequent phylogenetic analysis. From this, the HTLV types and subtypes circulating in the study population were defined. There was higher prevalence of HTLV-1 (71%) than of HTLV-2 (29%). HTLV-1 samples were classified as belonging to the Cosmopolitan subtype, Transcontinental subgroup; and the HTLV-2 samples as HTLV-2c. Analysis on the restriction fragment length polymorphisms of the env region and sequencing of the 5'LTR region identified a sample of HTLV-2b, for the first time in the Brazilian Amazon region. This emphasizes the need for ongoing molecular studies in this region, in order to have better understanding of the epidemiology of HTLV transmission in the population, and to enable epidemiological surveillance of the emergence of new types and subtypes.
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Characterization of mannose-binding lectin plasma levels and genetic polymorphisms in HIV-1-infected individuals
(2011-02) VALLINOTO, Antonio Carlos Rosário; FREITAS, Felipe Bonfim; GUIRELLI, Isabella; MACHADO, Luiz Fernando Almeida; AZEVEDO, Vânia Nakauth; VALLINOTO, Izaura Maria Vieira Cayres; ISHAK, Marluísa de Oliveira Guimarães; ISHAK, Ricardo
INTRODUCTION: The present study investigated the association between mannose-binding lectin (MBL) gene polymorphism and serum levels with infection by HIV-1. METHODS: Blood samples (5mL) were collected from 97 HIV-1-infected individuals resident in Belém, State of Pará, Brazil, who attended the Special Outpatient Unit for Infections and Parasitic Diseases (URE-DIPE). CD4+ T-lymphocyte count and plasma viral load were quantified. A 349bp fragment of exon 1 of the MBL was amplified via PCR, using genomic DNA extracted from controls and HIV-1-infected individuals, following established protocols. MBL plasma levels of the patients were quantified using an enzyme immunoassay kit. RESULTS: Two alleles were observed: MBL*O, with a frequency of 26.3% in HIV-1-infected individuals; and the wild allele MBL*A (73.7%). Similar frequencies were observed in the control group (p > 0.05). Genotype frequencies were distributed according to the Hardy-Weinberg equilibrium in both groups. Mean MBL plasma levels varied by genotype, with statistically significant differences between the AA and AO (p < 0.0001), and AA and OO (p < 0.001) genotypes, but not AO and OO (p = 0.17). Additionally, CD4+ T-lymphocytes and plasma viral load levels did not differ significantly by genotype (p > 0.05). CONCLUSIONS: The results of this study do not support the hypothesis that MBL gene polymorphism or low plasma MBL concentrations might have a direct influence on HIV-1 infection, although a broader study involving a large number of patients is needed.
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Characterization of polymorphisms in the mannose-binding lectin gene promoter among human immunodeficiency virus 1 infected subjects
(2008-11) VALLINOTO, Antonio Carlos Rosário; MUTO, Nilton Akio; ALVES, Anna Elizabeth Martins; MACHADO, Luiz Fernando Almeida; AZEVEDO, Vânia Nakauth; SOUZA, Lia Lobato Batista de; ISHAK, Marluísa de Oliveira Guimarães; ISHAK, Ricardo
The present study investigated the prevalence of mutations in the -550 (H/L) and -221 (X/Y) mannose-binding lectin (MBL) gene promoter regions and their impact on infection by human immunodeficiency virus 1 (HIV-1) in a population of 128 HIV-1 seropositive and 97 seronegative patients. The allele identification was performed through the sequence-specific primer polymerase chain reaction method, using primer sequences specific to each polymorphism. The evolution of the infection was evaluated through CD4+ T-lymphocyte counts and plasma viral load. The allele and haplotype frequencies among HIV-1-infected patients and seronegative healthy control patients did not show significant differences. CD4+ T-lymphocyte counts showed lower levels among seropositive patients carrying haplotypes LY, LX and HX, as compared to those carrying the HY haplotype. Mean plasma viral load was higher among seropositive patients with haplotypes LY, LX and HX than among those carrying the HY haplotype. When promoter and exon 1 mutations were matched, it was possible to identify a significantly higher viral load among HIV-1 infected individuals carrying haplotypes correlated to low serum levels of MBL. The current study shows that haplotypes related to medium and low MBL serum levels might directly influence the evolution of viral progression in patients. Therefore, it is suggested that the identification of haplotypes within the promoter region of the MBL gene among HIV-1 infected persons should be further evaluated as a prognostic tool for AIDS progression.
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Frequencies of CCR5-D32, CCR2-64I and SDF1-3'A mutations in Human Immunodeficiency Virus (HIV) seropositive subjects and seronegative individuals from the state of Pará in Brazilian Amazonia
(2005-12) CARVALHAES, Fernanda Andreza de Pinho Lott; CARDOSO, Greice de Lemos; VALLINOTO, Antonio Carlos Rosário; MACHADO, Luiz Fernando Almeida; ISHAK, Marluísa de Oliveira Guimarães; ISHAK, Ricardo; GUERREIRO, João Farias
The distribution of genetic polymorphisms of chemokine receptors CCR5-D32, CCR2-64I and chemokine (SDF1-3 A) mutations were studied in 110 Human Immunodeficiency Virus type 1 (HIV-1) seropositive individuals (seropositive group) and 139 seronegative individuals (seronegative group) from the population of the northern Brazilian city of Belém which is the capital of the state of Pará in the Brazilian Amazon. The CCR5-D32 mutation was found in the two groups at similar frequencies, i.e. 2.2% for the seronegative group and 2.7% for the seropositive group. The frequencies of the SDF1-3 A mutation were 21.0% for the seronegative group and 15.4% for the seropositive group, and the CCR2-64I allele was found at frequencies of 12.5% for the seronegative group and 5.4% for the seropositive group. Genotype distributions were consistent with Hardy-Weinberg expectations in both groups, suggesting that none of the three mutations has a detectable selective effect. Difference in the allelic and genotypic frequencies was statistically significant for the CCR2 locus, the frequency in the seronegative group being twice that found in the seropositive group. This finding may indicate a protective effect of the CCR2-64I mutation in relation to HIV transmission. However, considering that the CCR2-64I mutation has been more strongly associated with a decreased risk for progression for AIDS than to the resistance to the HIV infection, this could reflect an aspect of population structure or a Type I error.
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Identification of human T-cell lymphotropic virus infection in a semi-isolated Afro-Brazilian quilombo located in the Marajó Island (Pará, Brazil)
(2006-02) VALLINOTO, Antonio Carlos Rosário; PONTES, Gemilson Soares; MUTO, Nilton Akio; LOPES, Ivina Giselle Lima; MACHADO, Luiz Fernando Almeida; AZEVEDO, Vânia Nakauth; CARVALHAES, Fernanda Andreza de Pinho Lott; SANTOS, Sidney Emanuel Batista dos; GUERREIRO, João Farias; ISHAK, Marluísa de Oliveira Guimarães; ISHAK, Ricardo
Antibodies to human T-cell lymphotropic virus-1 and 2 (HTLV-1 and 2) were tested in 259 inhabitants (98 males and 161 females) of four villages of the Marajó Island (Pará, Brazil) using enzyme immunoassays (ELISA and Western blot). Types and subtypes of HTLV were determined by nested polymerase chain reaction (PCR) targeting the pX, env and 5´LTR regions. HTLV-1 infection was detected in Santana do Arari (2.06%) and Ponta de Pedras (1%). HTLV-2 was detected only in Santana do Arari (1.06%). Sequencing of the 5´LTR region of HTLV-1 and the phylogenetic analysis identified the virus as a member of the Cosmopolitan Group, subgroup Transcontinental. Santana do Arari is an Afro-Brazilian community and the current results represent the first report of HTLV-1 infection in a mocambo located in the Brazilian Amazon region.
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Investigação do vírus Epstein-Barr em pacientes com Periodontite Crônica
(2013-04) FARIAS, Cleysiane Gonçalves; PONTE, Nicole Patrícia de Lima Vinagre da; AMANAJÁS, Thalita de Almeida; LAURENTINO, Rogério Valois; MACHADO, Luiz Fernando Almeida; ALVES, Ana Claudia Braga Amoras
INTRODUCTION: In recent years, a growing number of studies have suggested the participation of the herpes virus in periodontal disease. OBJECTIVE: this study investigates the relationship between the presence of the Epstein-Barr herpes virus and periodontal infection in patients with chronic periodontitis. METHODOLOGY: subgingival biofilm samples were collected of subgingival sites with probing depths of 4 mm to 6 mm, and > 7 of 28 patients with chronic periodontitis. The control group consisted of 16 healthy subjects without clinical evidence of chronic periodontitis. Additionally, clinical parameters of probing depth, attachment level and Bleeding index were recorded. RESULT: the results showed averages of 2 mm probing depth, 1, 7 mm attachment level and 0.3 % bleeding on probing. Investigation of the herpes virus in the subgingival biofilm of the groups was performed using polymerase chain reaction with species-specific primer. Results of viral analysis indicated the absence of EBV in all subgingival samples analyzed. CONCLUSION: these results found no relationship between the presence of the Epstein-Barr herpes virus and chronic periodontitis.
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JC virus/human immunodeficiency virus 1 co-infection in the Brazilian Amazonian region
(Sociedade Brasileira de Infectologia, 2016-08) VALLINOTO, Izaura Maria Vieira Cayres; VALLINOTO, Antonio Carlos Rosário; PENA, Giselle Priscila dos Anjos; AZEVEDO, Vânia Nakauth; MACHADO, Luiz Fernando Almeida; ISHAK, Marluísa de Oliveira Guimarães; ISHAK, Ricardo
JC virus (JCV) is a member of the Polyomaviridae family and is associated with a severe disease known as progressive multifocal leukoencephalopathy, PML, which is progressively increasing in incidence as an opportunistic infection among AIDS patients. The present study aimed to investigate the occurrence of JCV among HIV-1 carriers including their types and molecular subtypes and the possible association with disease.Urine samples from 66 HIV-1 infected subjects were investigated for the presence of the virus by amplifying VP1 (215 bp) and IG (610 bp) regions using the polymerase chain reaction. JCV was detected in 32% of the samples. The results confirmed the occurrence of type B (subtype Af2); in addition, another polyomavirus, BKV, was also detected in 1.5% of samples of the HIV-1 infected subjects. Apparently, there was no significant difference between mono- (HIV-1 only) and co-infected (HIV-1 / JCV) subjects regarding their TCD4 + / TCD8 + lymphocyte counts or HIV-1 viral plasma load. Self admitted seizures, hearing and visual loses were not significantly different between the two groups.
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Mannose-binding lectin 2 (Mbl2) gene polymorphisms are related to protein plasma levels, but not to heart disease and infection by Chlamydia
(Universidade Federal do Pará, 2016-12) QUEIROZ, Maria Alice Freitas; GOMES, Samara Tatielle Monteiro; ALMEIDA, Núbia Caroline Costa de; SOUSA, Maria Izete Machado de; COSTA, Suzanne Roberta Cardoso Fernandes; HERMES, Renata Bezerra; LIMA, Sandra Souza; ZANINOTTO, Marcelo Martins; FOSSA, Marco Antonio Ayin ; MANESCYH, Manoel Araujo; FEITOSA, Rosimar Neris Martins; AZEVEDO, Vânia Nakauth; MACHADO, Luiz Fernando Almeida; ISHAK, Marluísa de Oliveira Guimarães; ISHAK, Ricardo; VALLINOTO, Antonio Carlos Rosário
The presence of the single nucleotide polymorphisms in exon 1 of the mannose-binding lectin 2 (MBL2) gene was evaluated in a sample of 159 patients undergoing coronary artery bypass surgery (71 patients undergoing valve replacement surgery and 300 control subjects) to investigate a possible association between polymorphisms and heart disease with Chlamydia infection. The identification of the alleles B and D was performed using real time polymerase chain reaction (PCR) and of the allele C was accomplished through PCR assays followed by digestion with the restriction enzyme. The comparative analysis of allelic and genotypic frequencies between the three groups did not reveal any significant difference, even when related to previous Chlamydia infection. Variations in the MBL plasma levels were influenced by the presence of polymorphisms, being significantly higher in the group of cardiac patients, but without representing a risk for the disease. The results showed that despite MBL2 gene polymorphisms being associated with the protein plasma levels, the polymorphisms were not enough to predict the development of heart disease, regardless of infection with both species of Chlamydia.
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Molecular characterization of human T-cell lymphotropic virus coinfecting human immunodeficiency virus 1 infected patients in the Amazon region of Brazil
(2005-07) LAURENTINO, Rogério Valois; LOPES, Ivina Giselle Lima; AZEVEDO, Vânia Nakauth; MACHADO, Luiz Fernando Almeida; MOREIRA, Márcio Ronaldo Chagas; SOUZA, Lia Lobato Batista de; ISHAK, Marluísa de Oliveira Guimarães; ISHAK, Ricardo; VALLINOTO, Antonio Carlos Rosário
The present work evaluated the epidemiology of human immunodeficiency virus 1/human T-cell lymphotropic virus (HIV-1/HTLV) coinfection in patients living in Belém (state of Pará) and Macapá (state of Amapá), two cities located in the Amazon region of Brazil. A total of 169 blood samples were collected. The sera were tested by enzyme-linked immunosorbent assay to determine the presence of antibodies anti-HTLV-1/2. Confirmation of infection and discrimination of HTLV types and subtypes was performed using a nested polymerase chain reaction targeting the pX and 5' LTR regions, followed by restriction fragment length polymorphism and sequencing analysis. The presence of anti-HTLV1/2 was detected in six patients from Belém. The amplification of the pX region followed by RFLP analysis, demonstrated the presence of HTLV-1 and HTLV-2 infections among two and four patients, respectively. Sequencing HTLV-1 5' LTR indicated that the virus is a member of the Cosmopolitan Group, Transcontinental subgroup. HTLV-2 strains isolated revealed a molecular profile of subtype HTLV-2c. These results are a reflex of the epidemiological features of HIV-1/HTLV-1/2 coinfection in the North region of Brazil, which is distinct from other Brazilian regions, as reported by previous studies.
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Polymorphism in the promoter region of the mannose-binding lectin gene among human T-cell lymphotropic virus infected subjects
(2007-12) ALVES, Anna Elizabeth Martins; HERMES, Renata Bezerra; TAMEGÃO-LOPES, Bruna Pedroso; AZEVEDO, Vânia Nakauth; MACHADO, Luiz Fernando Almeida; ISHAK, Marluísa de Oliveira Guimarães; ISHAK, Ricardo; LEMOS, José Alexandre Rodrigues de; VALLINOTO, Antonio Carlos Rosário
The present study investigated the frequency of the mutations at positions -550 and -221 of the mannose-binding lectin (MBL) gene in a sample of 75 human T-cell lymphotropic virus (HTLV) infected patients and 96 HTLV seronegative controls, in order to evaluate the occurrence of a possible association between the polymorphism and HTLV infection. A sequence specific primer-polymerase chain reaction was used for discrimination of the polymorphism. The analysis of allele frequencies at position -550 did not show any significant differences between HTLV infected group and controls, but there was a significant difference at position -221. The comparative analysis of haplotypes frequencies were not significant, but the genotype frequencies between the two groups, revealed a higher prevalence of genotype LYLX (25.3%), associated with medium and low MBL serum levels among HTLV infected subjects. The odds ratio estimation demonstrated that the presence of genotype LYLX was associated with an increased risk of HTLV infection (p = 0.0096; 1.38 < IC95% < 7.7605). There was no association between proviral load and the promoter polymorphism, but when promoter and exon 1 mutations were matched, it was possible to identify a significant higher proviral load among HTLV infected individuals carrying haplotypes correlated to low serum levels of MBL. The present study shows that the polymorphism in the promoter region of the MBL gene may be a genetic marker associated with HTLV infection, and emphasizes the need for further studies to determinate if the present polymorphism have any impact on diseases linked to HTLV infection.
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Soroprevalência de infecções por vírus da hepatite B e vírus da hepatite C em indivíduos do Estado do Pará
(2008-08) AQUINO, José Américo; PEGADO, Katia Abrahim; BARROS, Lilian Patrícia Souza; MACHADO, Luiz Fernando Almeida
Hepatitis B and C continue to be important public health problems in Brazil. In this study, the prevalence of serological markers for hepatitis B and C in individuals from the State of Pará, attended at the Central Public Health Laboratory of Pará between January 2002 and December 2005, was determined. 11,282 tests to investigate HBsAg, 2,342 for anti-HBc and 5,542 for anti-HCV were performed. The prevalence of HBsAg was 3.6% and it was predominantly found in the age range of 20 to 29 years old, while anti-HBC was observed in 37.7% of the subjects. The prevalence of anti-hepatitis C virus was 3.6% and it was predominantly found in individuals over 50 years old. Thus, the frequencies of the markers found in Pará were higher than many other states in Brazil, hence suggesting that there is a need for public health measures of greater effectiveness for combating these illnesses in this region.
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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.