Navegando por Autor "ISHAK, Ricardo"

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Assessment of the sensory and physical limitations imposed by leprosy in a Brazilian Amazon Population
(Universidade Federal do Pará, 2017-04) ABEN-ATHAR, Cintia Yolette Urbano Pauxis; LIMA, Sandra Souza; ISHAK, Ricardo; VALLINOTO, Antonio Carlos Rosário
Introduction: Leprosy often results in sensory and physical limitations. This study aimed to evaluate these limitations using a quantitative approach in leprosy patients in Belém (Pará, Brazil). Methods: This epidemiological, cross-sectional study measured the sensory impairment of smell and taste through the use of a questionnaire and evaluated activity limitations of daily life imposed by leprosy through the Screening of Activity Limitation and Safety Awareness (SALSA) Scale. Data were collected from 84 patients and associations between the degree of disability and clinical and epidemiological characteristics were assessed. Results: The majority of patients were men (64.3%), married (52.4%), age 31-40 years old (26.2%), had primary education (50%), and were independent laborers (36.9%). The multibacillary operational classification (81%), borderline clinical form (57.1%), and 0 degrees of physical disability (41.7%) were predominant. SALSA scores ranged from 17 to 59 points, and being without limitations was predominant (53.6%). The risk awareness score ranged from 0 to 8, with a score of 0 (no awareness of risk) being the most common (56%). Evaluation of smell and taste sensory sensitivities revealed that 70.2% did not experience these sensory changes. Patients with leprosy reactions were 7 times more likely to develop activity limitations, and those who had physical disabilities were approximately four times more likely to develop a clinical picture of activity limitations. Conclusions: Most patients showed no sensory changes, but patients with leprosy reactions were significantly more likely to develop activity limitations. Finally, further studies should be performed, assessing a higher number of patients to confirm the present results.
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Biossegurança no laboratório
(1989-04) ISHAK, Ricardo; LINHARES, Alexandre da Costa; ISHAK, Marluísa de Oliveira Guimarães
The occurrence of laboratory-acquired infections have elicited in the last ten years an intense interest in methods and procedures for the safe handling of microbiological material. The major laboratory safety problem is aerial transmission, however, protection against airborne hazards is efficiently achieved by the use of microbiological safety cabinets. Biosafety rules should be strictly followed by all members of a laboratory. Evaluation of these procedures should be effectively performed by an independent biosafety committee. The/ upsurge of AIDS should stimulate the adoption of safe working procedures in the laboratory.
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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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Chlamydia trachomatis serotype A infections in the Amazon region of Brazil: prevalence, entry and dissemination
(Universidade Federal do Pará, 2015-04) ISHAK, Marluísa de Oliveira Guimarães; COSTA, Maurimélia Mesquita da; ALMEIDA, Núbia Caroline Costa de; SANTIAGO, Angélica Menezes; BRITO, William Botelho de; VALLINOTO, Antonio Carlos Rosário; AZEVEDO, Vânia Nakauth; ISHAK, Ricardo
INTRODUCTION: Chlamydia infection is associated with debilitating human diseases including trachoma, pneumonia, coronary heart disease and urogenital diseases. Serotypes of C. trachomatis show a fair correlation with the group of diseases they cause, and their distribution follows a well-described geographic pattern. Serotype A, a trachoma-associated strain, is known for its limited dissemination in the Middle East and Northern Africa. However, knowledge on the spread of bacteria from the genus Chlamydia as well as the distribution of serotypes in Brazil is quite limited. METHODS: Blood samples of 1,710 individuals from ten human population groups in the Amazon region of Brazil were examined for antibodies to Chlamydia using indirect immunofluorescence and microimmunofluorescence assays. RESULTS: The prevalence of antibodies to Chlamydia ranged from 23.9% (Wayana-Apalai) to 90.7% (Awa-Guaja) with a mean prevalence of 50.2%. Seroreactivity was detected to C. pneumoniae and to all serotypes of C. trachomatis tested; furthermore, we report clear evidence of the as-yet-undescribed occurrence of serotype A of C. trachomatis. CONCLUSIONS: Specific seroreactivity not only accounts for the large extent of dissemination of C. trachomatis in the Amazon region of Brazil but also shows an expanded area of occurrence of serotype A outside the epidemiological settings previously described. Furthermore, these data suggest possible routes of Chlamydia introduction into the Amazon region from the massive human migration that occurred during the 1,700s.
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Detection of HTLV-IIa in blood donors in an urban area of the Amazon Region of Brazil (Belém, PA)
(1998-04) ISHAK, Ricardo; ISHAK, Marluísa de Oliveira Guimarães; SANTOS, Domingos Ezenildo Matos dos; VALLINOTO, Antonio Carlos Rosário; SARAIVA, João Carlos Pina; CRESCENTE, Jose Angelo Barletta; HALL, William W.; AZEVEDO, Vânia Nakauth
The human lymphotropic viruses type I (HTLV-I) and type II (HTLV-II) are members of a group of mammalian retroviruses with similar biological properties, and blood transfusion is an important route of transmission. HTLV-I is endemic in a number of different geographical areas and is associated with several clinical disorders. HTLV-II is endemic in several Indian groups of the Americas and intravenous drug abusers in North and South America, Europe and Southeast Asia. During the year of 1995, all blood donors tested positive to HTLV-I/II in the State Blood Bank (HEMOPA), were directed to a physician and to the Virus Laboratory at the Universidade Federal do Pará for counselling and laboratory diagnosis confirmation. Thirty-five sera were tested by an enzyme immune assay, and a Western blot that discriminates HTLV-I and HTLV-II infection. Two HTLV-II positive samples were submitted to PCR analysis of pX and env genomic region, and confirmed to be of subtype IIa. This is the first detection in Belém of the presence of HTLV-IIa infection among blood donors. This result emphasizes that HTLV-II is also present in urban areas of the Amazon region of Brazil and highlights the need to include screening tests that are capable to detect antibodies for both types of HTLV.
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Epidemiological aspects of retrovirus (HTLV) infection among Indian populations in the Amazon Region of Brazil
(2003-08) ISHAK, Ricardo; VALLINOTO, Antonio Carlos Rosário; AZEVEDO, Vânia Nakauth; ISHAK, Marluísa de Oliveira Guimarães
HTLV was initially described in association with a form of leukemia in Japan and a neurological disease in the Caribbean. It was soon shown that HTLV-II was endemic among Amerindians and particularly among Brazilian Indians. The Amazon Region of Brazil is presently the largest endemic area for this virus and has allowed several studies concerning virus biology, the search for overt disease, epidemiological data including detailed demographic data on infected individuals, clear-cut geographic distribution, definition of modes of transmission and maintenance within small, epidemiologically-closed groups, and advances in laboratory diagnosis of the infection. A new molecular subtype named HTLV-IIc was further described on the basis of genome sequencing and phylogenetic analysis. This subtype is present in other areas of Brazil, indicating that the virus is additionally both a valuable marker for tracing past human migration routes in the Americas and a probable marker for social habits of the present human population. HIV, the other human retrovirus, is still not prevalent among indigenous communities in the Brazilian Amazon, but these groups are also easy targets for the virus.
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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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HTLV-I associated myelopathy in the northern region of Brazil (Belém-Pará): serological and clinical features of three cases
(2002-06) ISHAK, Ricardo; CAVALCANTE, Fernando; VALLINOTO, Antonio Carlos Rosário; AZEVEDO, Vânia Nakauth; ISHAK, Marluísa de Oliveira Guimarães
Three patients (males, black, ages 37, 40 and 57) attended a university clinic with a progressive paraparesis of obscure origin. One patient who referred disease duration of more than 16 years, showed diminished deep reflexes, bilateral Babinski's sign, diminished sensation of vibration, abnormal bladder function and back pain. The other two patients (with one and six years of disease duration) complained of weakness in one leg, increased deep reflexes and back pain. Babinski's sign and bladder disturbance were also present in the patient with six years of disease. Blood samples tested by an enzyme immune assay and a discriminatory Western blot were positive for HTLV-I. The familial analysis of one patient showed a possible pattern of sexual and vertical transmission of the virus. To the best of our knowledge, these are the first cases of a proven association between HTLV-I and TSP/HAM in Belem, Para, and emphasize the need to actively look for cases of neurological disease associated to the virus.
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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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O impacto da infecção por Chlamydia em populações indígenas da Amazônia brasileira
(2001-04) ISHAK, Marluísa de Oliveira Guimarães; ISHAK, Ricardo
Knowledge is limited on the spread of bacteria from genus Chlamydia in Brazil. This study included a sero-epidemiological survey of 2,086 samples from native Indian populations of the Brazilian Amazon region. Sera were screened using indirect immunofluorescence assay for detection of antibodies to C. trachomatis serotype L2, followed by microimmunofluorescence assay using fifteen C. trachomatis and C. pneumoniae serotypes as antigen substrates. Antibody prevalence was 48.6%, but there was a large prevalence range among the groups, including those that had never been challenged with the bacteria, as well as those in which almost all individuals had been infected. Titration of IgG antibodies and detection of specific IgM in high-titer samples showed the persistence of Chlamydia in 6.1% of the reactive individuals, who probably play an important role as reservoirs for dissemination of the bacteria. Specific seroreactivity to C. trachomatis showed the presence of serotypes A, B, Ba, D, E, G, H, I, and L1 in the geographic area surveyed. Furthermore, the survey showed that C. pneumoniae was also infecting these individuals. Both species may be involved in a significant human disease burden that merits further clarification.
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JC polyomavirus infection in candidates for kidney transplantation living in the Brazilian Amazon Region
(2013-04) MELO, Fernando de Assis Ferreira; BEZERRA, Ana Caroline Fonseca; SANTANA, Bárbara Brasil; ISHAK, Marluísa de Oliveira Guimarães; ISHAK, Ricardo; VALLINOTO, Izaura Maria Vieira Cayres; VALLINOTO, Antonio Carlos Rosário
This study evaluated the relative occurrences of BK virus (BKV) and JC virus (JCV) infections in patients with chronic kidney disease (CKD). Urine samples were analysed from CKD patients and from 99 patients without CKD as a control. A total of 100 urine samples were analysed from the experimental (CKD patients) group and 99 from the control group. Following DNA extraction, polymerase chain reaction (PCR) was used to amplify a 173 bp region of the gene encoding the T antigen of the BKV and JCV. JCV and BKV infections were differentiated based on the enzymatic digestion of the amplified products using BamHI endonuclease. The results indicated that none of the patients in either group was infected with the BKV, whereas 11.1% (11/99) of the control group subjects and 4% (4/100) of the kidney patients were infected with the JCV. High levels of urea in the excreted urine, low urinary cellularity, reduced bladder washout and a delay in analysing the samples may have contributed to the low prevalence of infection. The results indicate that there is a need to increase the sensitivity of assays used to detect viruses in patients with CDK, especially given that polyomavirus infections, especially BKV, can lead to a loss of kidney function following transplantation.
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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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Lack of evidence for human infection with Xenotropic murine leukemia virus-related virus in the Brazilian Amazon basin
(2014-06) GOMES, Samara Tatielle Monteiro; IMBIRIBA, Luciana; BURBANO, Rommel Mario Rodriguéz; SILVA, Artur Luiz da Costa da; FEITOSA, Rosimar Neris Martins; VALLINOTO, Izaura Maria Vieira Cayres; ISHAK, Marluísa de Oliveira Guimarães; ISHAK, Ricardo; VALLINOTO, Antonio Carlos Rosário
Introduction: This study confirmed the absence of natural infection with Xenotropic murine leukemia virus-related virus (XMRV) or XMRV-related disease in human populations of the Brazilian Amazon basin. We demonstrated that 803 individuals of both sexes, who were residents of Belem in the Brazilian State of Pará, were not infected with XMRV. Methods: Individuals were divided into 4 subgroups: healthy individuals, individuals infected with human immunodeficiency virus, type 1 (HIV-1), individuals infected with human T-lymphotrophic virus, types 1 or 2 (HTLV-1/2), and individuals with prostate cancer. XMRV infection was investigated by nested PCR to detect the viral gag gene and by quantitative PCR to detect pol. Results: There was no amplification of either gag or pol segments from XRMV in any of the samples examined. Conclusions: This study supports the conclusions of the studies that eventually led to the retraction of the original study reporting the association between XMRV and human diseases.
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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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Molecular evidence of mother-to-child transmission of HTLV-IIc in the Kararao Village (Kayapo) in the Amazon Region of Brazil
(2001-12) ISHAK, Ricardo; VALLINOTO, Antonio Carlos Rosário; AZEVEDO, Vânia Nakauth; LEWIS, Martha; HALL, William W.; ISHAK, Marluísa de Oliveira Guimarães
Blood samples from native Indians in the Kararao village (Kayapo), were analysed using serological and molecular methods to characterize infection and analyse transmission of HTLV-II. Specific reactivity was observed in 3/26 individuals, of which two samples were from a mother and child. RFLP analysis of the pX and env regions confirmed HTLV-II infection. Nucleotide sequence of the 5' LTR segment and phylogenetic analysis showed a high similarity (98%) between the three samples and prototype HTLV-IIa (Mot), and confirmed the occurrence of the HTLV-IIc subtype. There was a high genetic similarity (99.9%) between the mother and child samples and the only difference was a deletion of two nucleotides (TC) in the mother sequence. Previous epidemiological studies among native Indians from Brazil have provided evidence of intrafamilial and vertical transmission of HTLV-IIc. The present study now provides molecular evidence of mother-to-child transmission of HTLV-IIc, a mechanism that is in large part responsible for the endemicity of HTLV in these relatively closed populations. Although the actual route of transmission is unknown, breast feeding would appear to be most likely.
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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.