15 results on '"V. N. Azevedo"'
Search Results
2. Prevalence of syphilis in female sex workers in three countryside cities of the state of Pará, Brazilian Amazon
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André Luis Ribeiro Ribeiro, Luiz Fernando Almeida Machado, V. N. Azevedo, Lucimar Di Paula dos Santos Madeira, Jacqueline Cortinhas Monteiro, Rosimar Neris Martins Feitosa, Ronaldo Lopes de Souza, João Bráullio de Luna Sales, Marluísa de Oliveira Guimarães Ishak, Ricardo Ishak, Rachel Macedo da Silva, Aldemir B. Oliveira-Filho, and Marcelo Victor Serejo Pereira
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Adult ,medicine.medical_specialty ,Adolescent ,Epidemiology ,Sexual Behavior ,Sex workers ,Amazon region ,law.invention ,lcsh:Infectious and parasitic diseases ,Condoms ,symbols.namesake ,Young Adult ,Condom ,law ,Risk Factors ,medicine ,Prevalence ,Humans ,lcsh:RC109-216 ,Poisson regression ,Treponema pallidum ,Syphilis ,Risk factor ,Cities ,business.industry ,Transmission (medicine) ,Middle Aged ,medicine.disease ,Syphilis Serodiagnosis ,Sexual intercourse ,Infectious Diseases ,Cross-Sectional Studies ,Sexual Partners ,symbols ,Educational Status ,Female ,Rural area ,business ,Brazil ,Demography ,Research Article - Abstract
Background Syphilis is a sexually transmitted infection (STI) transmitted from person to person mainly by sexual intercourse or through vertical transmission during pregnancy. Female sex workers (FSWs) are exposed especially to syphilis infection, and besides all the efforts to control the spread of STIs, syphilis prevalence is still rising, mainly occurring in low-income countries. This study aimed to investigate the syphilis prevalence, demographic characteristics and sexual habits among FSWs in the Amazon region of Brazil. Methods A cross-sectional study was carried out including 184 FSWs from 3 countryside cities of the state of Pará, Amazon region of Brazil. A venereal disease research laboratory test and an indirect immunoenzyme assay to test antibodies against Treponema pallidum were used for screening syphilis infection, while sexual habits and demographic data information were collected through a semi-structured questionnaire. Data was analyzed comparing groups with/without syphilis. Poisson regression models were used to estimate the reasons of prevalence (RP). Results The overall prevalence of syphilis was 14.1% (95% CI = 9.8–17.8). FSWs had between 15 and 56 years of age, most were unmarried (65.7%), had attended less than 8 years of formal education (64.1%), had between 10 and 20 partners per week (64.1%), and reported no previous history of STIs (76.1%) and regular use of condom (52.7%). Low level of education attending up to the primary school (RP adjusted = 3.8; 95% CI = 1.4–9.2) and high frequency of anal sex during the past year (RP adjusted = 9.3; 95% CI = 3.5–28.7) were associated with a higher prevalence of syphilis. Conclusions A high prevalence of syphilis among FSWs in the Brazilian Amazon region was identified, showing that syphilis is more likely to be transmitted in FSW working in low-income areas, which is attributed to the low level of education. Anal intercourse was found as a risk factor associated with syphilis. Health programs focused on risk populations appear as a rational way to control syphilis spread, which is a rising problem in Brazil and in other several countries.
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- 2020
3. Eugenol influences the expression of messenger RNAs for superoxide dismutase and glutathione peroxidase 1 in bovine secondary follicles cultured
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A.L.P. Souza, A. W. B. Silva, L.R.F.M. Paulino, J. R. V. Silva, P A A Barroso, Francisco das Chagas Costa, E I T de Assis, B.R. Silva, E M Vasconcelos, and A V N Azevedo
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0301 basic medicine ,GPX1 ,Ovarian Cortex ,Andrology ,Superoxide dismutase ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Glutathione Peroxidase GPX1 ,Ovarian Follicle ,Gene expression ,Follicular phase ,Eugenol ,Animals ,RNA, Messenger ,Antrum ,Glutathione Peroxidase ,030219 obstetrics & reproductive medicine ,biology ,Chemistry ,Superoxide Dismutase ,Cell Biology ,030104 developmental biology ,biology.protein ,Ethidium homodimer assay ,Cattle ,Female ,Developmental Biology - Abstract
SummaryThis study aimed to investigate the effects of eugenol on growth, viability, antrum formation and mRNA expression of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase 1 (GPX1) and peroxiredoxin 6 (PRDX6) in bovine secondary follicles cultured in vitro. To this end, bovine ovaries were collected from a local slaughterhouse and in the laboratory the follicles were isolated from the ovarian cortex. The follicles were then cultured in TCM-199+ alone or supplemented with different concentrations of eugenol (0.5, 5.0 and 50.0 μM). Follicular diameters and antrum formation were evaluated on days 0, 6, 12 and 18. Viability analysis was performed using calcein and ethidium homodimer. Real-time PCR was used to quantify mRNA levels for SOD, CAT, GPX1 and PRDX6 in cultured follicles. Follicular diameters and mRNA levels in follicles cultured in vitro were compared using analysis of variance and Kruskal–Wallis tests, while follicular survival and antrum formation were compared using the chi-squared test (P < 0.05). The results showed that secondary follicles cultured with eugenol maintained similar morphology and viability to follicles cultured in the control group. A progressive increase in follicular diameter was observed between days 0 and 12 for all treatments, except for follicles cultured with 50 µM eugenol. Eugenol (5.0 and 50.0 μM) increased mRNA levels for GPX1 in cultured follicles, but 0.5 μM eugenol reduced mRNA levels for SOD. The addition of eugenol did not influence mRNA expression for CAT and PRDX6. In conclusion, eugenol supplementation reduces mRNA levels for SOD and increases mRNA levels of GPX1 in bovine secondary follicles cultured in vitro.
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- 2021
4. HIV-1 Transmitted Drug Resistance Mutations in Recently Diagnosed Antiretroviral-Naive Patients in Belém, Pará, Northern Brazil
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V. N. Azevedo, M Santos, Maria Karoliny da Silva Torres, Luiz Fernando Almeida Machado, Rosimar Neris Martins Feitosa, Maria E.S. Avelino, Felipe Bonfim Freitas, Antonio Carlos Rosário Vallinoto, Susan D Flores Irias, and Maria Alice Freitas Queiroz
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Adult ,Male ,Immunology ,Human immunodeficiency virus (HIV) ,HIV Infections ,Drug resistance ,medicine.disease_cause ,Antirretrovirais / administra??o & dosagem ,Virology ,Drug Resistance, Viral ,medicine ,Antiretroviral naive ,Estudos Transversais ,Humans ,HIV-1 / patogenicidade ,business.industry ,HIV-1 / efeitos dos f?rmacos ,Tratamento Farmacol?gico / utiliza??o ,Infectious Diseases ,Cross-Sectional Studies ,Anti-Retroviral Agents ,Carta ,Mutation ,HIV-1 ,Female ,business ,Brazil - Abstract
Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Programa de P?s-Gradua??o em Biologia de Agentes Infecciosos e Parasit?rios. Bel?m, PA, Brazil / Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Programa de P?s-Gradua??o em Biologia de Agentes Infecciosos e Parasit?rios. Bel?m, PA, Brazil / Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Programa de P?s-Gradua??o em Biologia de Agentes Infecciosos e Parasit?rios. Bel?m, PA, Brazil / Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Programa de P?s-Gradua??o em Biologia de Agentes Infecciosos e Parasit?rios. Bel?m, PA, Brazil / Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Ananindeua, PA, Brasil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Programa de P?s-Gradua??o em Biologia de Agentes Infecciosos e Parasit?rios. Bel?m, PA, Brazil / Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil.
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- 2018
5. SEROPREVALENCE OF HEPATITIS B AND HEPATITIS C VIRUS INFECTIONS IN DENTISTS FROM BELEM, PARA, BRAZIL
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A.C.R. Costa, Ricardo Ishak, R. N. M. Feitosa, L.Q. Siravenha, Antonio Carlos Rosário Vallinoto, V. N. Azevedo, and Luiz Fernando Almeida Machado
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business.industry ,Hepatitis C virus ,medicine ,Seroprevalence ,Hepatitis B ,medicine.disease ,business ,medicine.disease_cause ,Virology - Published
- 2018
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6. Short Communication: Serological and Molecular Typing of HIV Type 1 Infection in the Tiriyo Tribe, a Native Indian Community of the Amazon Region of Brazil
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Maria I.M. Souza, V. N. Azevedo, Antonio Carlos Rosário Vallinoto, Marluísa de Oliveira Guimarães Ishak, Ricardo Ishak, and Luiz Fernando Almeida Machado
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Molecular epidemiology ,Amazon rainforest ,Immunology ,food and beverages ,Biology ,Tribe (biology) ,medicine.disease ,Virology ,humanities ,Serology ,Infectious Diseases ,Acquired immunodeficiency syndrome (AIDS) ,parasitic diseases ,Genotype ,medicine ,population characteristics ,Seroprevalence ,Viral disease ,geographic locations - Abstract
The seroprevalence and the occurrence of an HIV-1 subtype was assessed in blood samples of the Tiriyo tribe. Antibody was found in 0.6% and the molecular analysis of the pro region detected the emergence of a subtype B for the first time in a native Indian tribe of the Amazon region of Brazil.
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- 2006
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7. Molecular evidence for infection by HTLV-2 among individuals with negative serological screening tests for HTLV antibodies
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William W. Hall, Ana Carolina Paulo Vicente, V. N. Azevedo, Ricardo Ishak, M. O. G. Ishak, and Antonio Carlos Rosário Vallinoto
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TaqI ,Epidemiology ,viruses ,Polymerase Chain Reaction ,Sensitivity and Specificity ,Serology ,Immunoenzyme Techniques ,chemistry.chemical_compound ,Western blot ,medicine ,RNA Viruses ,Phylogeny ,Phylogenetic tree ,biology ,medicine.diagnostic_test ,Human T-lymphotropic virus 2 ,biology.organism_classification ,HTLV-I Infections ,Virology ,Molecular biology ,Deltaretrovirus ,HTLV-II Antibodies ,Infectious Diseases ,chemistry ,biology.protein ,Antibody ,Restriction fragment length polymorphism ,Nested polymerase chain reaction ,Brazil ,Polymorphism, Restriction Fragment Length ,Research Article - Abstract
SUMMARYPrevious serological studies on the Arara do Laranjal Indian group revealed extensive HTLV-2 infections. A collection of 97 new samples from the Arara were found repeatedly negative using three different commercial enzyme immunoassays. Eight samples that exhibited optical density readings close to the cut-off value were re-evaluated using Western blot (GeneLab 2.4, Singapore) assay. One sample was found to be non-reactive, five exhibited indeterminate patterns, one was classified as HTLV, and one was confirmed as HTLV-2. Peripheral blood mononuclear cell DNA of the eight samples were subjected to nested PCR and restriction fragment length polymorphism (RFLP) analysis of thepXandenvregions, and nucleotide sequencing of the 5′-LTRregion. All produced amplification products ofpX, butenvcould be amplified in only one sample with the commonly used primers. RFLP analysis of thepXregion usingTaqI confirmed HTLV-2 infection. Nucleotide sequencing of the 5′-LTRregion was performed in three samples (HTLV-2, HTLV and indeterminate based on Western blot pattern). Phylogenetic analysis of a 449-nt fragment using the Neighbour-Joining method clearly demonstrated that the three samples clustered within the HTLV-2c molecular subtype. The present study confirms the wide dissemination of the HTLV-2c subtype among linguistically and culturally distinct Amazonian Indian groups, and emphasizes the unique occurrence of infection by this subtype in Brazil. Moreover, it emphasizes the limitation of employing the present serological screening assays in blood banks, epidemiological studies, and the importance of molecular assays in the confirmatory procedures for the primary detection of HTLV-2 infections.
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- 2006
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8. PREVALENCE AND GENOTYPE DIVERSITY OF ANAL HPV INFECTION AMONG HIV-INFECTED WOMEN IN BELEM, PARA, NORTH OF BRAZIL
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Rodrigo Vellasco Duarte Silvestre, V. N. Azevedo, Jacqueline Cortinhas Monteiro, Antonio Carlos Rosário Vallinoto, Rogério Valois Laurentino, Andreza Reis Brasil da Silva, Luana Lorena Silva Rodrigues, Luiz Fernando Almeida Machado, R. N. M. Feitosa, and Ricardo Ishak
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media_common.quotation_subject ,Hiv infected ,Genotype ,HPV infection ,medicine ,Biology ,medicine.disease ,Virology ,Diversity (politics) ,media_common - Published
- 2018
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9. Molecular epidemiology of HIV type 1 in northern Brazil: identification of subtypes C and D and the introduction of CRF02_AG in the Amazon region of Brazil
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V. N. Azevedo, Ricardo Ishak, Luiz Fernando Almeida Machado, Márcio Ronaldo Chagas Moreira, Luciana M. Fernandes, Maria I.M. Souza, Marluísa de Oliveira Guimarães Ishak, Lia Lobato Batista de Souza, Antonio Carlos Rosário Vallinoto, and José Alexandre Rodrigues de Lemos
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Adult ,Male ,Adolescent ,Genotype ,Immunology ,Population ,Human immunodeficiency virus (HIV) ,Sequence Homology ,HIV Infections ,medicine.disease_cause ,Genetic analysis ,Virus ,Central laboratory ,Young Adult ,HIV Protease ,Virology ,medicine ,Cluster Analysis ,Humans ,education ,Phylogeny ,Aged ,education.field_of_study ,Molecular Epidemiology ,Molecular epidemiology ,Amazon rainforest ,business.industry ,env Gene Products, Human Immunodeficiency Virus ,virus diseases ,Sequence Analysis, DNA ,Middle Aged ,Infectious Diseases ,HIV-1 ,Female ,business ,Brazil - Abstract
The molecular epidemiology of HIV-1 strains circulating in Belem-PA and Macapa-AP, in the Northern region of Brazil, is described using sequences of the C2V3 segment of the env and the pro gene of HIV-1 from patients of the Reference Unit for Special Infectious and Parasitary Diseases (URE-DIPE) in Belem-PA and the Central Laboratory (LACEN) in Macapa-AP. Subtype B was the most frequently found in relation to pro (88.3%) in Belem and in Macapa (97.1%) and env (88.3% in Belem and 100% in Macapa). Subtype F was also described in Belem (9.3% pro and 8.3% env) and Macapa (2.8% pro). Subtype D was described for the first time in the Northern region of the country as well as the recent entry of CRF02_AG. Furthermore, several possible recombinant forms among the various subtypes were found in both cities. The results support the hypothesis that HIV-1 infection is associated with the epidemic of the virus in the Southeast region of the country and that the city of Belem is the most important route for HIV-1 entry in the Northern region of Brazil.
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- 2009
10. Characterization of mannose-binding lectin gene polymorphism among human T-cell lymphotropic virus 1 and 2-infected asymptomatic subjects
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Luiz Fernando Almeida Machado, Gemilson Soares Pontes, José Alexandre Rodrigues de Lemos, Antonio Carlos Rosário Vallinoto, Bruna Pedroso Tamegão-Lopes, Ricardo Ishak, M. O. G. Ishak, and V. N. Azevedo
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Human T-lymphotropic virus 1 ,Deltaretrovirus Infections ,Polymorphism, Genetic ,Genotype ,Immunology ,Human T-lymphotropic virus 2 ,chemical and pharmacologic phenomena ,General Medicine ,Immunogenetics ,Biology ,bacterial infections and mycoses ,Asymptomatic ,Virology ,Mannose-Binding Lectin ,Virus ,Histocompatibility ,medicine ,Immunology and Allergy ,Humans ,Gene polymorphism ,medicine.symptom ,Restriction fragment length polymorphism ,Mannan-binding lectin - Abstract
The present study investigated the associa- tion between mannose-binding lectin (MBL) gene polymor- phism and the susceptibility to human T-cell lymphotropic virus (HTLV) infection in a group of 83 HTLV-infected asymptomatic subjects (62 HTLV-1 and 21 HTLV-2) and 99 healthy controls. Detection of MBL*A, MBL*B, and MBL*C was performed by amplifying a fragment of 349 bp (exon 1) and submitting the product to restriction fragment length polymorphism analysis with BanI and MboII endo- nucleases. Allele MBL*D was investigated by sequence- specific primer-polymerase chain reaction. The frequency of MBL*A, MBL*B, and MBL*D was 63%, 22%, and 15% among seropositive subjects and 70%, 14%, and 16% among healthy controls, respectively. Genotype differences were statistically significant ( 2 11.57; p 0.04); the presence of genotype BB was 9.6% among HTLV-infected patients compared with 1% among controls ( 2 7.151; p 0.019). A significant difference of the genotype fre- quencies between HTLV-1 and HTLV-2 infections was observed, but this result could be attributed to the number of investigated HTLV-1-infected subjects. The odds ratio to the presence of BB genotype was 10.453 (1.279 IC95% 85.40; p 0.019). Results reveal a strong association between MBL polymorphism and HTLV infection. Pres- ence of genotype BB may be associated with the suscepti- bility to HTLV, but further studies, with a larger number of individuals, will be necessary. MBL polymorphism could possibly have an impact on diseases associated with HTLV infection. Human Immunology 66, 892-896 (2005). © American Society for Histocompatibility and Immunogenetics, 2005. Published by Elsevier Inc.
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- 2005
11. Molecular epidemiology of human T-lymphotropic virus type II infection in Amerindian and urban populations of the Amazon region of Brazil
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William W. Hall, Marluísa de Oliveira Guimarães Ishak, V. N. Azevedo, Ricardo Ishak, Koko Otsuki, Ana Carolina Paulo Vicente, and Antonio Carlos Rosário Vallinoto
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Endemic Diseases ,Urban Population ,viruses ,Population ,Zoology ,Blood Donors ,HIV Infections ,Human T-lymphotropic virus ,Colonialism ,Polymerase Chain Reaction ,Virus ,Evolution, Molecular ,immune system diseases ,hemic and lymphatic diseases ,Genetics ,Humans ,Colonization ,education ,Genetics (clinical) ,Ecology, Evolution, Behavior and Systematics ,Phylogeny ,education.field_of_study ,Human T-lymphotropic virus 1 ,Molecular Epidemiology ,Molecular epidemiology ,Phylogenetic tree ,biology ,Base Sequence ,Amazon rainforest ,Indians, South American ,Human T-lymphotropic virus 2 ,virus diseases ,Emigration and Immigration ,biology.organism_classification ,Virology ,Founder Effect ,Phenotype ,Population Surveillance ,HTLV-II Infections ,Brazil ,Polymorphism, Restriction Fragment Length ,Founder effect - Abstract
Molecular characterization of human T-cell lymphotropic virus II (HTLV-II) isolates in North America and Europe has shown the existence of two principal subtypes of the virus, HTLV-IIa and HTLV-IIb. Subsequent studies on HTLV-II isolates from Brazil have suggested the existence of a unique variant phylogenetically related to HTLV-IIa but phenotypically similar to HTLV-IIb with respect to the transactivatory protein, Tax. This variant has been designated HTLV-IIc. To better clarify the variability and distribution of HTLV-II in Brazil, the viruses present in two population groups from the Amazon region were tested for the presence of HTLV-II using serological and molecular assays. The groups consisted of blood donors from three Amerindian communities and of HIV-1/HTLV-II coinfected patients residing in Belem, an urban area. Nucleotide sequences and phylogenetic analysis confirmed the presence of HTLV-IIc subtype among Amerindian populations and, for the first time, the presence of the same virus among urban groups in Belem. The isolated occurrence of the HTLV-IIc subtype among Amerindian populations in the Amazon region could be attributed to (1) the different migratory pathways and founder effect, or (2) the local origin of a proto-HTLV-II carried by Amerindian ancestors who migrated to the Amazon circa 11,000 to 13,000 years ago. These results suggest that not only is HTLV-IIc unique to this region, but that its presence in urban areas of Brazil has resulted from admixture processes during the colonization of the country.
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- 2002
12. Identification of human T cell lymphotropic virus type IIa infection in the Kayapo, an indigenous population of Brazil
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V. N. Azevedo, Ricardo Ishak, William J. Harrington, Sidney Santos, William W. Hall, Takayuki Kubo, Nobutaka Eiraku, S. S. Alexander, Marluísa de Oliveira Guimarães Ishak, João Farias Guerreiro, and Claude Monken
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Adult ,Male ,Sexual transmission ,Adolescent ,viruses ,Immunology ,Population ,Blotting, Western ,Molecular Sequence Data ,Biology ,Genes, env ,Polymerase Chain Reaction ,Virus ,Serology ,Sex Factors ,Virology ,Prevalence ,Seroprevalence ,Humans ,education ,Child ,Phylogeny ,Aged ,DNA Primers ,education.field_of_study ,Sex Characteristics ,Base Sequence ,Geography ,Transmission (medicine) ,Indians, South American ,Human T-lymphotropic virus 2 ,Age Factors ,Infant, Newborn ,Infant ,Middle Aged ,Infectious Disease Transmission, Vertical ,Pedigree ,HTLV-II Antibodies ,Infectious Diseases ,Child, Preschool ,HTLV-II Infections ,Female ,Viral disease ,Restriction fragment length polymorphism ,Brazil ,Polymorphism, Restriction Fragment Length - Abstract
Human T cell lymphotropic virus type II (HTLV-II) infection is endemic in a number of indigenous populations in North, Central, and South America. In the present study we have employed serological and molecular methods to identify HTLV-II infection in Indian communities in the Amazon region of Brazil. Sera (1324) from 25 different Indian communities were analyzed by ELISA and Western blot. One hundred and four samples (7.8%) from a number of culturally distinct and geographically unrelated populations were found to have reactivities consistent with HTLV-II infection. Of these, 67 were from the Kayapo Indian communities, which had an overall seroprevalence rate of greater than 30%. In addition, high seroprevalence rates were observed in three other communities, the Munduruku, Arara do Laranjal and the Tyrio, suggesting that there are additional foci of endemic infection in the Amazon region. In the Kayapo, seroprevalence rates tended to increase with age, supporting the importance of sexual transmission of the virus, and family studies demonstrated that vertical transmission is also an important route of infection. Restriction fragment length polymorphism (RFLP) and nucleotide sequence analysis of a region of the env gene demonstrated that the Kayapo are infected with the HTLV-IIa subtype. Moreover, nucleotide sequence analysis of the LTR demonstrated that this belonged to a distinct HTLV-IIa phylogenetic group. The identification of HTLV-IIa in the Kayapo is, as far as we are aware, the first identified endemic focus of infection by this subtype of HTLV-II in the Americas.
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- 1995
13. Characterization of polymorphisms in the mannose-binding lectin gene promoter among human immunodeficiency virus 1 infected subjects
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Antonio Carlos Rosário Vallinoto, Ricardo Ishak, M. O. G. Ishak, V. N. Azevedo, A. E. M. Alves, Nilton Akio Muto, Lia Lobato Batista de Souza, and Luiz Fernando Almeida Machado
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Genetic Markers ,Microbiology (medical) ,lcsh:Arctic medicine. Tropical medicine ,lcsh:RC955-962 ,Population ,Pará - Estado ,lcsh:QR1-502 ,HIV Infections ,Polimorfismo genético MBL ,Biology ,Polymerase Chain Reaction ,Belém - PA ,lcsh:Microbiology ,Polymorphism (computer science) ,HIV Seronegativity ,Humans ,genetic polymorphism ,Genetic Predisposition to Disease ,Prevalência ,mannose-binding lectin ,Allele ,Promoter Regions, Genetic ,education ,Mannan-binding lectin ,education.field_of_study ,Polymorphism, Genetic ,human immunodeficiency virus ,Haplotype ,Promoter ,Viral Load ,Virology ,Amazônia brasileira ,CD4 Lymphocyte Count ,Haplotypes ,Case-Control Studies ,Mutation ,Disease Progression ,HIV-1 ,Primer (molecular biology) ,Viral load - Abstract
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.
14. Polymorphism in the promoter region of the mannose-binding lectin gene among human T-cell lymphotropic virus infected subjects
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Antonio Carlos Rosário Vallinoto, Bruna Pedroso Tamegão-Lopes, V. N. Azevedo, A. E. M. Alves, Luiz Fernando Almeida Machado, Renata B. Hermes, Ricardo Ishak, M. O. G. Ishak, and José Alexandre Rodrigues de Lemos
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Adult ,Genetic Markers ,Male ,Microbiology (medical) ,human T-cell lymphotropic virus ,lcsh:Arctic medicine. Tropical medicine ,lcsh:RC955-962 ,lcsh:QR1-502 ,Biology ,Polymerase Chain Reaction ,Virus ,lcsh:Microbiology ,Genotype ,Humans ,genetic polymorphism ,mannose-binding lectin ,Allele frequency ,Gene ,Mannan-binding lectin ,Human T-lymphotropic virus 1 ,Polymorphism, Genetic ,Human T-lymphotropic virus 2 ,Haplotype ,HTLV-I Infections ,Virology ,Genotype frequency ,Haplotypes ,Genetic marker ,Case-Control Studies ,HTLV-II Infections ,Mutation ,Immunology ,Female ,Disease Susceptibility - Abstract
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; 1.38or = IC95%or = 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.
15. Mannose-binding lectin 2 (Mbl2) gene polymorphisms are related to protein plasma levels, but not to heart disease and infection by Chlamydia
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V. N. Azevedo, M.I.M. Souza, Sandra Souza Lima, Núbia Caroline Costa de Almeida, M.M. Zaninotto, Luiz Fernando Almeida Machado, Samara Tatielle Monteiro Gomes, M.A.A. Fossa, Rosimar Neris Martins-Feitosa, Maria Alice Freitas Queiroz, Ricardo Ishak, Renata B. Hermes, M. O. G. Ishak, M.A. Maneschy, S.R.C.F. Costa, and Antonio C. R. Vallinoto
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Male ,0301 basic medicine ,Genotype ,Heart disease ,Physiology ,Immunology ,Heart Valve Diseases ,Biophysics ,Ocean Engineering ,Single-nucleotide polymorphism ,Biology ,Polymerase Chain Reaction ,Polymorphism, Single Nucleotide ,Biochemistry ,03 medical and health sciences ,Gene Frequency ,medicine ,Humans ,Genetic Predisposition to Disease ,General Pharmacology, Toxicology and Pharmaceutics ,Allele ,Chlamydia ,Allele frequency ,lcsh:QH301-705.5 ,Mannan-binding lectin ,Mannose-binding lectin ,lcsh:R5-920 ,General Neuroscience ,Biomedical Sciences ,Cell Biology ,General Medicine ,Chlamydia Infections ,Middle Aged ,medicine.disease ,Molecular biology ,Cross-Sectional Studies ,030104 developmental biology ,Real-time polymerase chain reaction ,lcsh:Biology (General) ,Case-Control Studies ,Female ,Polymorphisms ,lcsh:Medicine (General) - Abstract
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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