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1.
Rev. Inst. Med. Trop. Säo Paulo ; 56(6): 511-515, Nov-Dec/2014. tab
Article in English | LILACS | ID: lil-725811

ABSTRACT

This study evaluated epidemiological factors for HCV infection associated with sharing perforating and cutting instruments among candidates for blood donation (CBD) in the city of Belém, Pará, Brazilian Amazon. Two definitions of HCV infection cases were used: anti-HCV positivity shown by EIA, and HCV-RNA detection by PCR. Infected and uninfected CBD completed a questionnaire about possible risk factors associated with sharing perforating and cutting instruments. The information was evaluated using simple and multiple logistic regressions. Between May and November 2010, 146 (1.1%) persons with anti-HCV antibodies and 106 (0.8%) with HCV-RNA were detected among 13,772 CBD in Belém. Risk factors associated with HCV infection based on the EIA (model 1) and PCR (model 2) results were: use of needles and syringes sterilized at home; shared use of razors at home, sharing of disposable razors in barbershops, beauty salons etc.; and sharing manicure and pedicure material. The models of HCV infection associated with sharing perforating and cutting instruments should be taken into account by local and regional health authorities and by those of other countries with similar cultural practices, in order to provide useful information to guide political and public strategies to control HCV transmission.


Este estudo avaliou fatores epidemiológicos para infecção pelo HCV associados ao compartilhamento de instrumentos cortantes e perfurantes em candidatos à doação de sangue (CDS) na cidade de Belém, Pará, Amazônia Brasileira. Duas definições de infecção pelo HCV foram utilizadas: positividade por anti-HCV detectada por EIA, e HCV-RNA detectado por PCR. CDS infectados e não-infectados preencheram questionário sobre possíveis fatores de risco associados com o compartilhamento de instrumentos cortantes e perfurantes. As informações foram avaliadas usando regressão logística simples e múltipla. Entre maio e novembro de 2010, 146 (1,1%) indivíduos com anticorpos anti-HCV e 106 (0,8%) com HCV-RNA foram detectadas entre 13.772 CDS em Belém. Os fatores de risco associados à infecção pelo HCV baseado em resultados de EIA (modelo 1) e PCR (modelo 2) foram: uso de agulhas e seringas esterilizadas em casa, uso compartilhado de lâminas em casa, compartilhamento de lâminas em barbearias, salões de beleza, etc., e compartilhamento de material de manicure e pedicure. Os modelos de infecção pelo HCV associados com o compartilhamento de instrumentos cortantes e perfurantes devem ser considerados pelas autoridades de saúde local e regional e de países com práticas culturais semelhantes, a fim de fornecer informações uteis para direcionar estratégias e políticas públicas de controle da transmissão do HCV.


Subject(s)
Adolescent , Adult , Female , Humans , Male , Middle Aged , Young Adult , Blood Donors/statistics & numerical data , Hepatitis C/transmission , Brazil/epidemiology , Cross-Sectional Studies , Hepatitis C/epidemiology , Risk Factors , Socioeconomic Factors
2.
Rev. Inst. Med. Trop. Säo Paulo ; 55(5): 323-328, Sep-Oct/2013. tab
Article in English | LILACS | ID: lil-685547

ABSTRACT

SUMMARY In Brazil, the existing reference values for T-lymphocytes subsets are based on data originated in other countries. There is no local information on normal variation for these parameters in Brazilian adults and children. We evaluated the normal variation found in blood donors from five large Brazilian cities, in different regions, and in children living in Salvador, and Rio de Janeiro. All samples were processed by flow cytometry. The results were analyzed according to region, gender, and lifestyle of blood donors. A total of 641 adults (63% males), and 280 children (58% males) were involved in the study. The absolute CD3+, and CD4+ cells count were significantly higher for females (adults and children). Higher CD4+ cell count in adults was associated with smoking, while higher CD8+ count was found among female children. Higher counts, for all T-cells subsets, were detected in blood donors from southeast / south regions while those living in the northern region had the lowest values. Individuals from midwestern and northeastern regions had an intermediate count for all these cells subsets. However, these differences did not reach statistical significance. In Brazil, gender and smoking, were the main determinants of differences in T-lymphocytes reference values. .


RESUMO Os valores de referências de linfócitos T existentes no Brasil são baseados em dados originados de outros países. Não existem dados locais da variação normal para estes parâmetros em adultos e crianças brasileiras. Avaliamos a variação normal encontrada em doadores de sangue de cinco grandes cidades brasileiras em diferentes regiões e em crianças residentes em Salvador e Rio de Janeiro. Todas as amostras foram processadas por citometria de fluxo. Os resultados foram analisados de acordo com região, gênero e estilo de vida dos doadores. Um total de 641 adultos (63% homens) e 280 crianças (58% meninos) participaram do estudo. Valores absolutos de CD3+ e CD4+ foram significantemente maiores no gênero feminino (adultos e crianças). Maiores valores de CD4+ em adultos foram associados com tabagismo, enquanto que maiores valores de CD8+ foram encontrados entre crianças do sexo feminino. Adultos das regiões sul e sudeste apresentaram maiores valores absolutos para todas as células T enquanto que adultos da região norte, apresentaram menores valores. Indivíduos residentes no nordeste e centro-oeste obtiveram contagens intermediárias para todas as populações de células T. Entretanto, estas diferenças entre as regiões, não demonstraram diferença estatística. No Brasil, gênero e tabagismo foram os principais determinantes para diferenças em valores de referências de linfócitos T. .


Subject(s)
Adult , Child , Female , Humans , Male , Lymphocyte Subsets/cytology , Age Factors , Blood Donors , Brazil , Flow Cytometry , Immunophenotyping , Lymphocyte Count , Lymphocyte Subsets/immunology , Reference Values
3.
Rev. para. med ; 27(2)abr.-jun. 2013. tab
Article in Portuguese | LILACS-Express | LILACS | ID: lil-681358

ABSTRACT

OBJETIVO: estudar a incidência dos genótipos 16 e 18 do HPV em mulheres, com ou sem citologia associada a efeito citopático compatível com HPV, provenientes do município de Barcarena - Pará. MÉTODO: participaram deste estudo 50 voluntarias, através de coleta cérvico-vaginal para realização de PCR-RT para HPV 16 e 18, e citologia convencional. RESULTADOS: a citologia mostrou prevalência de 02/50 casos de LSIL/NICI, associadas ao efeito citopático compatível com HPV. O genótipo 16 do HPV ocorreu em 04/05 casos e os genótipos 16/18 ocorreram em 01/05 casos, principalmente em mulheres que apresentavam lesões do tipo ASC-US ou LSIL/NIC I. CONSIDERAÇÕES FINAIS: a presença de alterações citológicas do tipo ASC-US ou LSIL/NIC I (p=0,0166) representou um importante alerta para a possível infecção pelos tipos 16 e 18 do HPV.


OBJECTIVE: studying the incidence of HPV genotypes 16 and 18 in women, with or without cytology associated with HPV, living in the municipality of Barcarena, Pará. METHOD: fiftyvolunteers participated in the study through cervicovaginal sampling for PCR-RT to test for HPV 16 and 18 and for conventional cytology of smears. RESULTS: cytology showed an incidence of 02/50 cases of LSIL/CINI associated with a cytopathic effect compatible with HPV. Genotype 16 of HPV occurred in 04/05 cases and genotype 16/18 in 01/05 cases, mainly in women who showed lesions of the ASC-US or LSIL/CINI type. CONCLUSIONS: the presence of cytological changes of the ASC-US or LSIL/CINI type (p=0.0166) represents an important flag for possible infection by HPV types 16 and 18.

4.
Rev. Soc. Bras. Med. Trop ; 44(1): 8-12, Jan.-Feb. 2011. ilus, tab
Article in English | LILACS | ID: lil-579822

ABSTRACT

INTRODUCTION: Epidemiological studies concerning HCV genotypic distribution in the Brazilian Amazon are scarce. Thus, this study determined the patterns of distribution of HCV genotypes among different exposure categories in the State of Pará, Brazilian Amazon. METHODS: A cross-sectional study was conducted on 312 HCV-infected individuals belonging to different categories of exposure, who were attended at the HEMOPA, CENPREN and a private hemodialysis clinic in Belém. They were tested for HCV antibodies using an immunoenzymatic test, RNA-HCV, using real-time PCR and HCV genotyping through phylogenetic analysis of the 5' UTR. The population groups were epidemiologically characterized according to data collected in a brief interview or medical consultation. RESULTS: Genotype 1 predominated in all the different categories of HCV exposure. HCV genotypic distribution among blood donors comprised genotypes 1 (94 percent) and 3 (6 percent). All patients with chronic hematologic diseases had HCV genotype 1. The genotypic distribution in illicit-drug users comprised genotypes 1 (59.6 percent) and 3 (40.4 percent). In patients under hemodialysis, genotypes 1 (90.1 percent), 2 (3.3 percent), and 3 (6.6 percent) were detected. Finally, the frequency of genotypes 1 and 3 was significantly different between the groups: BD and DU, PUH and DU, PUH and PCHD and PCHD and DU. CONCLUSIONS: The genotypic frequency and distribution of HCV in different categories of exposure in the State of Pará showed a predominance of genotype 1, regardless of the possible risk of infection.


INTRODUÇÃO: Estudos epidemiológicos sobre a distribuição genotípica do HCV na Amazônia Brasileira são escassos. Baseado nisto, determinamos o padrão de distribuição genotípica do HCV em diferentes categorias de exposição no Estado do Pará, Amazônia Brasileira. MÉTODOS: Estudo transversal foi realizado com 312 indivíduos infectados pelo HCV, pertencentes a diferentes categorias de exposição atendidas pelo HEMOPA, CENPREN e uma clínica privada de hemodiálise em Belém. Eles foram testados quanto à presença de anticorpos anti-HCV por teste imunoenzimático, RNA-HCV utilizando PCR em tempo real e genotipados através de análise filogenética da 5' UTR. Os grupos de populações foram caracterizados epidemiologicamente de acordo com dados coletados em breve entrevista ou consulta de prontuários médicos. RESULTADOS: Em todas as diferentes categorias de exposição ao HCV, foram encontrados predomínio do genótipo 1. A distribuição genotípica do HCV em doadores de sangue (BD) foi constituída pelos genótipos 1 (94 por cento) e 3 (6 por cento). Todos os pacientes com doenças hematológicas crônicas (PCHD) possuíam genótipo 1. A distribuição genotípica em usuários de drogas ilícitas (DU) foi constituída pelos genótipos 1 (59,6 por cento) e 3 (40,4 por cento). Em pacientes em hemodiálise (PUH) foram detectados os genótipos 1 (90,1 por cento), 2 (3,3 por cento) e 3 (6,6 por cento). Finalmente, a frequência entre os genótipos 1 e 3 foi significativamente diferente entre os grupos: BD e DU, PUH e DU, PUH e PCHD, e PCHD e DU. CONCLUSÕES: A frequência genotípica e distribuição de HCV em diferentes categorias de exposição no Estado do Pará mostraram predominância do genótipo 1, independentemente do possível risco de infecção.


Subject(s)
Adult , Female , Humans , Male , Middle Aged , /genetics , Hepacivirus/genetics , Hepacivirus/immunology , Hepatitis C Antibodies/blood , Hepatitis C/virology , RNA, Viral/blood , Brazil/epidemiology , Cross-Sectional Studies , Genotype , Hepatitis C/epidemiology , Hepatitis C/transmission , Polymerase Chain Reaction
5.
Cad. saúde pública ; 26(4): 837-844, abr. 2010. tab
Article in English | LILACS | ID: lil-547219

ABSTRACT

We determined the risk factors for HCV infection in blood donors in the State of Pará, Northern Brazil. We examined 256 blood donors seen at the Blood Bank of Pará State between 2004 and 2006. They were divided into two groups, depending on whether they were infected with HCV or not; 116 donors were infected with HCV, while the other 140 were free of infection. The HCV-RNA was detected by real-time PCR. All of the participants filled out a questionnaire about possible risk factors. The data were evaluated using simple and multiple logistic regressions. The main risk factors for HCV were found to be use of needles and syringes sterilized at home (OR = 4.55), invasive dental treatment (OR = 3.08), shared use of razors at home (OR = 1.99), sharing of disposable razors in barbershops, beauty salons, etc. (OR = 2.34), and sharing manicure and pedicure material (OR = 3.45). Local and regional health authorities should educate the public about sharing perforating and cutting materials at home, in barber/beauty shops, and in dental clinics as risk factors for HCV infection.


Nós determinamos os fatores de risco à infecção pelo HCV em doadores de sangue no Estado do Pará, Brasil. Foram analisados 256 doadores de sangue atendidos na Fundação HEMOPA de 2004 a 2006, sendo divididos em dois grupos: infectados e não-infectados. O diagnóstico foi realizado por PCR em tempo real. Todos os participantes responderam a questionário sobre possíveis fatores de risco, sendo a modelagem estatística feita por regressão logística simples e múltipla. Os fatores de risco à infecção foram: uso de agulhas e seringas de vidros esterilizadas em casa (OR = 4,55), realização de tratamento dentário invasivo (OR = 3,08), compartilhamento de lâminas em domicílio (OR = 1,99), compartilhamento de lâminas descartáveis em barbearias, salões de beleza (OR = 2,34), e compartilhamento de material de manicure e pedicure (OR = 3,45). As autoridades de saúde devem conscientizar a população sobre o compartilhamento de materiais perfuro-cortantes em domicílio, salões de beleza e consultórios dentários como fatores de risco à infecção.


Subject(s)
Adult , Female , Humans , Male , Blood Donors/statistics & numerical data , Hepacivirus/genetics , Hepatitis C/transmission , RNA, Viral/blood , Brazil/epidemiology , Case-Control Studies , Hepatitis C/diagnosis , Hepatitis C/epidemiology , Polymerase Chain Reaction , Risk Factors , Surveys and Questionnaires
6.
Rev. Soc. Bras. Med. Trop ; 42(3): 271-276, May-June 2009. ilus
Article in Portuguese | LILACS | ID: lil-522255

ABSTRACT

Este trabalho objetivou a caracterização molecular do vírus linfotrópico de células T humanas infectando doadores de sangue atendidos na Fundação Centro de Hemoterapia e Hematologia do Pará. Amostras de DNA de 79 indivíduos soropositivos para o vírus linfotrópico de células T humanas foram analisadas por meio da reação em cadeia da polimerase para as regiões genômicas pX, env e 5'LTR, de polimorfismos de comprimento de fragmentos de restrição e do seqüenciamento da região 5LTR, com posterior análise filogenética, definindo o tipo e o subtipo do HTLV circulante na população estudada. Observou-se uma maior prevalência de HTLV-1 (71 por cento) em relação ao HTLV-2 (29 por cento). As amostras de HTLV-1 sequenciadas foram classificadas como pertencentes ao subtipo Cosmopolita, subgrupo Transcontinental, sendo as de HTLV-2 identificadas como HTLV-2c. A análise de polimorfismos de comprimento de fragmentos de restrição da região env e do sequenciamento da região 5'LTR, identificou, pela primeira vez na Amazônia Brasileira, uma amostra de HTLV-2b, enfatizando a necessidade de estudos moleculares contínuos na região para melhor entendimento da epidemiologia de transmissão do HTLV na população e permitir a vigilância epidemiológica da emergência de novos tipos e subtipos.


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 percent) than of HTLV-2 (29 percent). 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.


Subject(s)
Female , Humans , Male , Blood Donors , HTLV-I Infections/virology , HTLV-II Infections/virology , Human T-lymphotropic virus 1/genetics , /genetics , Base Sequence , Brazil , DNA, Viral/genetics , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length
7.
Clinics ; 64(8): 731-734, 2009. graf
Article in English | LILACS | ID: lil-523990

ABSTRACT

INTRODUCTION: In Brazil, patients with chronic myeloid leukemia (CML) in the chronic phase were not given first-line imatinib treatment until 2008. Therefore, there was a long period of time between diagnosis and the initiation of imatinib therapy for many patients. This study aims to compare the major molecular remission (MMR) rates of early versus late imatinib therapy in chronic phase CML patients. METHODS: Between May 2002 and November 2007, 44 patients with chronic phase CML were treated with second-line imatinib therapy at the Hematology Unit of the Ophir Loyola Hospital (Belém, Pará, Brazil). BCR-ABL transcript levels were measured at approximately six-month intervals using quantitative polymerase chain reaction. RESULTS: The early treatment group presented a 60 percent probability of achieving MMR, while the probability for those patients who received late treatment was 40 percent. The probability of either not achieving MMR within one year of the initiation of imatinib therapy or losing MMR was higher in patients who received late treatment (79 percent), compared with patients who received early treatment (21 percent, odds ratio=5.75, P=0.012). The probability of maintaining MMR at 30 months of treatment was 80 percent in the early treatment group and 44 percent in the late treatment group (P=0.0005). CONCLUSIONS: For CML patients in the chronic phase who were treated with second-line imatinib therapy, the probability of achieving and maintaining MMR was higher in patients who received early treatment compared with those patients for whom the time interval between diagnosis and initiation of imatinib therapy was longer than one year.


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Piperazines/therapeutic use , Protein Kinase Inhibitors/therapeutic use , Pyrimidines/therapeutic use , Fusion Proteins, bcr-abl/metabolism , Kaplan-Meier Estimate , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism , Remission Induction , Time Factors , Treatment Outcome , Young Adult
8.
Genet. mol. biol ; 32(2): 264-267, 2009. tab
Article in English | LILACS | ID: lil-513967

ABSTRACT

Most cases of a predisposition to venous thrombosis are caused by resistance to activated protein C, associated in 95 percent of cases with the Factor V Leiden allele (FVL or R506Q). Several recent studies report a further increased risk of thrombosis by an association between the AB alleles of the ABO blood group and Factor V Leiden. The present study investigated this association with deep vein thrombosis (DVT) in individuals treated at the Hemocentro de Pernambuco in northeastern Brazil. A case-control comparison showed a significant risk of thrombosis in the presence of Factor V Leiden (OR = 10.1), which was approximately doubled when the AB alleles of the ABO blood group were present as well (OR = 22.3). These results confirm that the increased risk of deep vein thrombosis in the combined presence of AB alleles and Factor V Leiden is also applicable to the Brazilian population suggesting that ABO blood group typing should be routinely added to FVL in studies involving thrombosis.

9.
Cad. saúde colet., (Rio J.) ; 15(3): 349-356, jul.-set. 2007. tab
Article in Portuguese | LILACS | ID: lil-527815

ABSTRACT

O vírus transmitido por transfusão sanguínea (TTV), primeiramente relatado por Nishizawa et al. (1997), teve sua etiologia associada a casos de hepatites pós-transfusionais não esclarecidas ocorridas na China. Este vírus possui uma molécula de DNA de fita simples e características moleculares que o classifica como membro da família Circoviridae. Nosso estudo avaliou a prevalência do TTV em pacientes com risco de exposição parenteral como doadores de sangue, em 186 amostras. Os participantes foram submetidos a questionário socioepidemiológico e assinaram termo de consentimento. Foram realizadas extrações de DNA das alíquotas de soro das amostras coletadas e amplificadas por PCR em tempo real, com a finalidade de se analisar o genoma viral. Após amplificação, foi observada a frequência do TTV em cerca de 60 por cento dos doadores (111 por 186). Não foram observadas relações estatisticamente significantes entre a infecção pelo TTV e o gênero dos doadores (p igual a 0,670), uso de drogas endovenosas (p igual a 0,476), presença de tatuagem (p igual a 0,887), promiscuidade (p igual a 0,291) e uso de preservativos (p igual a 0,644). Nossos resultados nos levam a concluir que a frequência de TTV não foi representativa como responsável por quadro de hepatite em nossa amostra. Isto está de acordo com a ausência de referência clínica de hepatites virais em nossa amostra.


Subject(s)
Humans , Blood Transfusion , Hepatitis , Tissue Donors
10.
Cad. saúde colet., (Rio J.) ; 15(3): 393-400, jul.-set. 2007. tab
Article in Portuguese | LILACS | ID: lil-527819

ABSTRACT

O citomegalovírus humano (HCMV) é um agente infeccioso da família Herpesviridae. Neste trabalho, perquisou-se HCMV através da PCR em Tempo Real, em 115 amostras de DNA extraído de leucócitos de indivíduos voluntários para doação de sangue no Centro de Hemoterapia do Pará. A presença do DNA viral foi evidenciada em 57 por cento dos indivíduos estudados, sendo que dois terços deles eram do sexo masculino, não tendo sido observada nenhuma relação significante entre faixa etária, gênero e presença do DNA viral. Os resultados através da PCR em Tempo Real nos permitem sugerir que os bancos de sangue introduzam a identificação do HCMV na escolha das amostras de sangue com leucócito que serão utilizadas em pacientes imunodeprimidos e mulheres em início de gestação, pelo fato do HCMV ser um vírus teratogênico.


Subject(s)
Humans , Blood Donors , Cytomegalovirus , Polymerase Chain Reaction
11.
Rev. Soc. Bras. Med. Trop ; 39(6): 548-552, nov.-dez. 2006. tab
Article in Portuguese | LILACS | ID: lil-447286

ABSTRACT

Os vírus linfotrópicos de células T humanas, quando integrados ao genoma da célula hospedeira, provírus, têm como marcador de replicação seu DNA proviral. A carga proviral parece ser um importante fator no desenvolvimento de patologias associadas a estes retrovírus. Neste estudo foi desenvolvida uma metodologia para quantificação absoluta da carga proviral dos HTLV-1 e HTLV-2 através da PCR em tempo real. Cinqüenta e três amostras de doadores de sangue com teste de ELISA reagente foram submetidas à metodologia, que utilizou o sistema TaqMan® para três seqüências alvo: HTLV-1, HTLV-2 e albumina. A quantificação proviral absoluta foi determinada através da proporção relativa entre o genoma do HTLV e o genoma da célula hospedeira, levando em consideração o número de leucócitos. O método apresentado é sensível (215 cópias/mL), prático e simples para quantificação proviral, além de eficiente e adequado para confirmação e discriminação da infecção pelos tipos virais.


When the human T cell lymphotropic virus (HTLV) is integrated with the host cell genome (provirus), its proviral DNA is a replication marker. Proviral load appears to be an important factor in the development of diseases related to these retroviruses. In this study, a methodology for absolute quantification of the HTLV-1 and HTLV-2 proviral load using real-time PCR was developed. Fifty-three blood donor samples with positive ELISA test result were subjected to this methodology, which utilized the TaqMan® system for three target sequences: HTLV-1, HTLV-2 and albumin. The absolute proviral load was quantified using the relative ratio between the HTLV genome and the host cell genome, taking into consideration the white blood cell count. The method presented is sensitive (215 copies/ml), practical and simple for proviral quantification, and is efficient and appropriate for confirming and discriminating infections according to viral type.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Human T-lymphotropic virus 1/genetics , /genetics , Polymerase Chain Reaction/methods , Proviruses/genetics , Viral Load/methods , Blood Donors , DNA, Viral/analysis , Enzyme-Linked Immunosorbent Assay , HTLV-I Infections/immunology , HTLV-I Infections/virology , HTLV-II Infections/immunology , HTLV-II Infections/virology , Human T-lymphotropic virus 1/immunology , /immunology , Proviruses/immunology , Reproducibility of Results
12.
São Paulo med. j ; 121(5): 203-206, Sept. 1, 2003. tab
Article in English | LILACS | ID: lil-349453

ABSTRACT

CONTEXT: Tumor suppressor genes act on the control of cell cycle progression. In pediatric neoplasias, some of these genes may be considered to be markers for diagnosis or relapse, thus probably representing prognostic indicators. OBJECTIVE: To study the inactivation of the p15 gene in children with acute lymphoblastic leukemia. TYPE OF STUDY: Retrospective study. SETTING: Laboratory of Molecular Biology, Department of Pediatrics, Faculdade de Medicina de Ribeiräo Preto, Universidade de Säo Paulo. PARTICIPANTS: Eighty-three children and adolescents with acute lymphoblastic leukemia were studied, with the examination of 83 bone marrow samples obtained at diagnosis, four obtained also during relapse, and two cerebrospinal fluid samples obtained from two cases of isolated relapse in the central nervous system. MAIN MEASUREMENTS: Homologous deletion of the p15 gene by multiplex polymerase chain reaction, and screening for point mutations by polymerase chain reaction/single-strand conformational polymorphism. RESULTS: Deletion of exon 2 of the p15 gene was observed in 15 children, including one case in which deletion was only verified during isolated central nervous system relapse. No case of exon 1 deletion, or that was suggestive of point mutations, was observed and no association between p15 gene inactivation and classic risk factors was established. CONCLUSION: According to the literature, inactivation of the p15 gene by deletion of exon 2 in acute lymphoblastic leukemia found in the population studied would be considered to be a molecular marker for diagnosis or relapse. However, no correlation between p15 gene deletion and clinical prognostic indicators was observed


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Suppression, Genetic , Gene Deletion , Gene Silencing , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Prognosis , Genetic Markers , Polymerase Chain Reaction , Exons , Retrospective Studies , Polymorphism, Single-Stranded Conformational
13.
São Paulo med. j ; 121(2): 58-62, Mar. 3, 2003. tab
Article in English | LILACS | ID: lil-342143

ABSTRACT

CONTEXT: The p16 tumor suppressor gene encodes a cyclin-dependent kinase 4 inhibitor that blocks cell division during the G1 phase of the cell cycle. Alterations in this gene have been reported for various neoplasia types, including acute lymphoblastic leukemias (ALL), especially T-cell acute lymphoblastic leukemias (ALL). OBJECTIVE: To determine probable alterations in the p16 gene in children with acute lymphoblastic leukemias using the polymerase chain reaction (PCR) and direct DNA sequencing and also to analyze event-free survival (EFS). DESIGN: Retrospective study. SETTING: Department of Child Care and Pediatrics, Faculty of Medicine of Ribeirão Preto, Universidade Federal de São Paulo. PARTICIPANTS: Fifty-six children with ALL (mean age 4 years). Forty (71.43 percent) had B-cell and 12 (21.43 percent) had T-cell ALL; 4 (7.1 percent) were biphenotypic. SAMPLE: DNA samples were extracted from bone marrow upon diagnosis and/or relapse. In 2 T-cell cases, DNA from cerebrospinal fluid (CSF) was analyzed. MAIN MEASUREMENTS: Deletions or nucleotide substitutions in exons 1, 2 and 3 of the p16 gene were determined by PCR and nucleotide sequencing. Event-free survival was determined by the Kaplan-Meyer and log-rank test for patients carrying normal and altered p16. RESULTS: Deletions in exon 3 were observed in five cases. Abnormal migration in PCR was observed in seven cases for exon 1, six for exon 2, and five for exon 3. Mutations in exon 1 were confirmed by direct DNA sequencing in four cases and in exon 2 in two cases. The Kaplan-Meyer survival curves and the log-rank test showed no significant differences in 5-year EFS between children with normal or altered p16, or between patients with B-ALL carrying normal or altered p16 gene. Patients with T-ALL could not be evaluated via Kaplan-Meier due to the small number of cases. CONCLUSIONS: Our results, particularly regarding deletion frequency, agree with others suggesting that deletions in the p16 are initial events in leukemia genesis. The small number of samples did not allow stablishment of correlation between childhood ALL and the p16 point mutations found in our study. Kaplan-Meier analysis revealed no significant correlation between EFS and alterations in ALL. The p16 alterations frequency observed for B and T-ALL agreed with reports from other centers


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Adolescent , Genes, p16 , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Mutation , Bone Marrow , Retrospective Studies , Gene Deletion , DNA Primers , Polymorphism, Single-Stranded Conformational
14.
Rev. para. med ; 16(4): 7-16, out.-dez. 2002. ilus, tab
Article in Portuguese | LILACS | ID: lil-331805

ABSTRACT

Introdução: A Leucemia Mielóide Crônica (LMC) é uma expansão clonal da célula progenitora hematopoética, constitui 14 por cento de todas as leucemias e sua incidência é de 1,6 casos a cada 100.000 habitantes. O marcador molecular da doença é o cromossoma Philadelphia. Objetivo: Atualizar diagnóstico e tratamento, considerando métodos clássicos e técnicas avançadas como protocolo para LMC. Método: levantamento bibliográfico recente e relevante de fontes indexadas sobre o tema. Considerações Finais: Os avanços tecnológicos trouxeram mais especificidade e sensibilidade ao diagnóstico da LMC. A maior compreensão dos mecanismos de ação da doença tornou possível a fabricação de drogas de ação específica, possibilitando um tratamento mais eficaz


Subject(s)
Humans , Male , Female , Philadelphia Chromosome , Reverse Transcriptase Polymerase Chain Reaction , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
15.
São Paulo med. j ; 118(2): 49-52, Mar. 2000. ilus, tab
Article in English | LILACS | ID: lil-289850

ABSTRACT

CONTEXT: Mutations of the p53 tumor suppressor gene are the most frequent alterations observed in human neoplasias affecting adults. In pediatric oncology, however, they have seldom been identified. WilmsÆ tumor is a renal neoplasia commonly occurring in children and is associated with mutations of the WT1 gene. The correlation between WilmsÆ tumor and alterations of the p53 gene has not been well established, with a low frequency of mutations having been reported in this type of tumor. Mutation may be associated with advanced stage disease and unfavorable histology. OBJECTIVE: To screen for mutations of the p53 gene by the PCR-SSCP method and DNA sequencing in cases of WilmsÆ tumor sug-gestive of mutation. DESIGN: Case Report. CASE REPORT: Evaluations of exons 5-9 of the p53 gene in DNA samples extracted by PCR-SSCP from 10 WilmsÆ tumors in children at different stages, and DNA sequencing. Changes in SSCP analy-sis were observed in exon 8 in two samples. The probable muta-tions were not confirmed by DNA sequencing. The absence of point mutations in p53 gene observed in the 10 samples of WilmsÆ tumor studied agrees with literature data, with DNA sequencing being of fundamental importance for the confirmation of possible mutations


Subject(s)
Humans , Infant , Child, Preschool , Child , Male , Female , Genes, p53/genetics , Wilms Tumor/genetics , Kidney Neoplasms/genetics , Mutation/genetics , Polymerase Chain Reaction/methods , Sequence Analysis, DNA , Polymorphism, Single-Stranded Conformational
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