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BACKGROUND: Helicobacter pylori infection occurs in 50% of the world's population and represents a major risk factor for chronic gastritis, gastroduodenal ulcer and gastric cancer in developed and developing countries. The distribution of H. pylori virulence factors is diverse and varies geographically, such as the CagA and VacA genes, which have revealed association with disease status. Some findings show increased frequencies of these diseases in O Le (a-b +) and A Le (a-b +) blood type individuals, but other studies not found any relationship between these blood groups and H. pylori infection. AIM: This study aimed to elucidate probable controversies described in the relationship between the ABH/Lewis blood groups and H. pylori, contributing to the severity of gastric diseases in northern the population of Belém -Pará.-Brazil. METHODS: This cross-sectional study included 288 samples of patients separate into two groups with gastric cancer and chronic gastritis. Blood, saliva, and gastric biopsy were analyzed using modified Gram and hematoxylin-eosin staining techniques, the enzyme immunoassay Elisa and Multiplex PCR. The antigens expression of ABH and Lewis systems was determined through Dot-ELISA and direct hemagglutination. Proportions were compared in univariate analysis, while the relation between putative risk factors including H. pylori status and ABO/Lewis phenotype was performed using multivariable logistic regression analyses, P-value < 0.05 was considered significant. RESULTS: The findings of this study demonstrate that the likelihood of developing gastric cancer increases threefold if the individual is from A1 Le (a-b +) blood group, has premalignant changes, and infection with H. pylori virulent strains (cagA+/vacA + s1m1). CONCLUSION: Therefore, this study found a significant association between ABO and Lewis phenotypes and H. pylori cagA status into the relevance of the development of gastric carcinogenesis.
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Infecciones por Helicobacter , Helicobacter pylori , Úlcera Péptica , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Brasil , Estudios Transversales , Genotipo , Helicobacter pylori/genética , HumanosRESUMEN
BACKGROUND: The Lewis (FUT3) gene is responsible for the expression of the Le(a) and Le(b) blood group antigens. The individuals, who not synthesize these antigens have the phenotype Lewis negative, due to the presence of some single nucleotide polymorphisms (SNPs), such as 59T>G, 508G>A and 1067T>A, whose distribution is different in various ethnic groups. Our aim was to verify the frequencies of these SNPs in an admixed population of Belém-Pará-Brazil. MATERIALS AND METHODS: Polymerase chain reaction/restriction enzyme method were used to detect these SNPs in the FUT3 gene, whereas Lewis phenotypes were defined by the direct hemagglutination and in saliva by Dot-Elisa assay in a random sample of 150 individuals from admixed population of Belém in the northeast Brazilian Amazon region. RESULTS: The frequency of these SNPs was detected as 47.6% (59T>G), 17.3% (508G>A) and 5.3% (1067T>A).The discrepancies between blood and salivary Lewis phenotypes are related to the relatively high frequencies of 59T>G and the null allele 508G>A. Whereas 38.6% of the individuals were Lewis negative based on blood, only 17.24% also tested negative when their saliva were analyzed. CONCLUSION: We have found a marked consistency between the phenotypes and genotypes of the Lewis blood group system. Furthermore, our obtained FST values reveal distinct frequencies of the FUT3 SNPs between the present sample and its representative ancestral populations. These observations will help to evaluate the Lewis antigens impact as susceptibility markers, in genetic association studies to certain diseases.
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Fucosiltransferasas/genética , Antígenos del Grupo Sanguíneo de Lewis/genética , Polimorfismo de Nucleótido Simple/genética , Adulto , Femenino , Genotipo , Humanos , Masculino , Polimorfismo Genético/genética , Adulto JovenRESUMEN
INTRODUCTION: This study compares virulence markers of Helicobacter pylori isolated from patients in 2 cities in the Brazilian Amazon. METHODS: The study analyzed 168 patients with chronic gastritis from Belém and 151 from Bragança, State of Pará, Brazil. Levels of bacterial DNA associated with cagA and vacA alleles were checked by PCR, and hematoxylin-eosin staining was used for histologic diagnosis. RESULTS: In Bragança 87% of patients were genotype s1m1 cagA-positive (s1m1 cagA+), compared with 76% in Belém. In samples from patients in both cities, there was an association between s1m1 cagA+ strains and gastric mucosal damage. CONCLUSIONS: Both cities have a high frequency of s1m1 cagA+ strains of H. pylori.
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Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Gastritis/microbiología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/patogenicidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/análisis , Brasil , Enfermedad Crónica , ADN Bacteriano/genética , Genotipo , Helicobacter pylori/genética , Helicobacter pylori/aislamiento & purificación , Humanos , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Factores de Virulencia/genética , Adulto JovenRESUMEN
Introduction This study compares virulence markers of Helicobacter pylori isolated from patients in 2 cities in the Brazilian Amazon. Methods The study analyzed 168 patients with chronic gastritis from Belém and 151 from Bragança, State of Pará, Brazil. Levels of bacterial DNA associated with cagA and vacA alleles were checked by PCR, and hematoxylin-eosin staining was used for histologic diagnosis. Results In Bragança 87% of patients were genotype s1m1 cagA-positive (s1m1 cagA+), compared with 76% in Belém. In samples from patients in both cities, there was an association between s1m1 cagA+ strains and gastric mucosal damage. Conclusions Both cities have a high frequency of s1m1 cagA+ strains of H. pylori. .
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Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Persona de Mediana Edad , Adulto Joven , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Gastritis/microbiología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/patogenicidad , Brasil , Biomarcadores/análisis , Enfermedad Crónica , ADN Bacteriano/genética , Genotipo , Helicobacter pylori/genética , Helicobacter pylori/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Factores de Virulencia/genéticaRESUMEN
OBJECTIVES: To investigate the risk factors for infection and the outcome of pregnancy in women diagnosed with syphilis using a molecular approach. METHODS: Case-control study of pregnant women admitted to a maternity ward, with the cases classified as early or latent maternal syphilis, based on clinical-serological diagnoses. The DNA of total peripheral blood was used to detect the polA gene using nested PCR (nPCR). The case and control groups were divided into subgroups based on whether the birth was successful (infant survived) or had a lethal outcome (miscarriage, stillbirth or neonatal death). RESULTS: The frequency of maternal syphilis was 1% (237/25 600), considering both those that had live births (71.3%, 169/237) and those with a lethal outcome (28.7%, 68/237), with a higher detection rate being provided by the nPCR in women with early syphilis. The cases of nPCR(+) congenital syphilis were more frequent in the women with early syphilis, nPCR(+) mothers and those who did not have treatment during the prenatal. The risk of maternal syphilis was greater in women who had not received preventive counselling, initiated sexual activity at 16 years of age or younger, had multiple partners, used drugs, were from households with a low income and poor sanitation, and had a history of miscarriage. CONCLUSIONS: The risk factors for congenital syphilis are closely related to the health of the mother, reflecting the lack of adequate prenatal care. The high frequency of maternal syphilis was associated in particular to the socio-economic conditions of the mother and her sexual and reproductive health.
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Técnicas de Diagnóstico Molecular/métodos , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/epidemiología , Resultado del Embarazo , Sífilis/epidemiología , Adolescente , Adulto , Estudios de Casos y Controles , Femenino , Muerte Fetal , Humanos , Recién Nacido , Embarazo , Prevalencia , Salud Reproductiva , Factores de Riesgo , Factores Socioeconómicos , Adulto JovenRESUMEN
Objetivo: revisar os aspectos imunopatogênicos da sífilis materno-fetal. Método: uma pesquisabibliográfica foi realizada utilizando-se as palavras-chave: sífilis congênita + imunopatogenia, sífilis materna+ imunopatogenia, sífilis + interface materno-fetal. As bases de dados pesquisadas foram a Medline (MedicalLiterature Analysis and Retrieval System Online) da National Library of Medicine (EUA) e a LILACS(Literatura Latino-Americana e do Caribe em Ciências da Saúde). Considerações finais: a infecção peloTreponema pallidum e o desenvolvimento das características clínicas deletérias deve-se ao êxito dosmecanismos de invasão, evasão e da resposta imunológica do hospedeiro. Na gestação ocorrem mudançashormonais, imunológicas e nutricionais necessárias ao bom desenvolvimento fetal que, porém, modulam asuscetibilidade materno-fetal à infecção. Nesse contexto, o perfil de citocinas na placenta tende a proteger ofeto de ser expulso, ao inibir a resposta celular citotóxica, dificultando, no entanto, a eliminação dotreponema da interface materno-fetal. Por outro lado, a resposta imunológica do feto ainda é imatura até a10ª - 20ª semana de gestação, permitindo que o patógeno invada, dissemine e escape. Assim, o diagnósticoprecoce para instituição do tratamento no recém-nascido é mandatório para prevenção das seqüelas e, comoainda não existe um exame laboratorial disponível na rede pública que permita esse diagnóstico em tempohábil, fica claro que um maior conhecimento da fisiopatogenia da doença é prioritário no sentido decontribuir para o avanço nas pesquisas clínicas
Objective: the objective of this study was to revise the immunopathogenic aspects of maternalfetalsyphilis. Methods: a detailed literature search of the Medline (Medical Literature Analysisand Online Retrieval System) of the American National Library of Medicine and the LILACS(Latin American and Caribbean Health Sciences) databases was conducted using the key wordscongenital syphilis + immunopathogeny, maternal syphilis + immunopathogeny, and syphilis +maternal-fetal interface. Final Considerations: the success of infection by T. pallidum and thedevelopment of deleterious clinical symptoms is due to the effectiveness of the mechanisms ofinvasion a, evasion and immunological response of the host. The hormonal, immunological, andnutritional changes that occur during pregnancy and are necessary for the successfuldevelopment of the fetus also modulate the susceptibility of the fetus to infection. In thiscontext, the cytokine profile of the placenta protects the fetus from expulsion by inhibiting thecytotoxic cell response, although this also hampers the elimination of the treponema from thematernal-fetal interface. However, the immunological response of the fetus is immature up untilthe 10-10th week of gestation, allowing the pathogen to invade, spread, and escape. Thus, theearly diagnosis for the treatment of the neonate is essential for the prevention of sequels, but asthe public health service does not provide clinical exams for the timely for the diagnosis of thiscondition, there is a clear need for a better understanding of the physiopathogeny of the diseasewith the specific objective of contributing to the advance of clinical research into the problem
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INTRODUCTION: Viral hepatitis is a major public health concern in Brazil. There are few past studies on this issue, especially among riparian communities. This study aims at determining the seroprevalence of viral hepatitis B and C in the riparian community of Pacuí Island, within the Cametá municipality of Pará State, Brazil. Moreover, this study aims to investigate the principal risk factors that this community is exposed to. METHODS: The current study has accessed blood samples from 181 volunteers who have answered an epidemiological questionnaire. Analyses on serological markers have been tested with commercial ELISA kits for detecting HBsAg, total anti-HBc, anti-HBs, and anti-HCV. Within seroreactive patients for HCV, RT-PCR and line probe assay have been performed to identify the viral genotype. RESULTS: In the serological marker analysis for hepatitis B, no reactivity for HBsAg, rate of 1.1% for total anti-HBc, and rate of 19.3% for anti-HBs have been observed. On hepatitis C, 8.8% seroprevalence has been found, in which 62.5% have gotten viral RNA. Among the risk factors studied, the following have been highlighted: non-use of condoms, sharing of cutting instruments, use of illicit drugs, and reports of family disease with HBV or HCV. CONCLUSIONS: The vaccination coverage against HBV is low, and the high prevalence of HCV within this community has been observed.
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Hepacivirus , Virus de la Hepatitis B , Hepatitis B/epidemiología , Hepatitis C/epidemiología , Adulto , Brasil/epidemiología , Brasil/etnología , ADN Viral/sangre , Ensayo de Immunospot Ligado a Enzimas , Femenino , Genotipo , Hepacivirus/genética , Hepacivirus/inmunología , Hepatitis B/diagnóstico , Anticuerpos contra la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/análisis , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Hepatitis C/diagnóstico , Anticuerpos contra la Hepatitis C/sangre , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Prevalencia , ARN Viral/sangre , Población Rural , Factores SocioeconómicosRESUMEN
INTRODUCTION: Viral hepatitis is a major public health concern in Brazil. There are few past studies on this issue, especially among riparian communities. This study aims at determining the seroprevalence of viral hepatitis B and C in the riparian community of Pacuí Island, within the Cametá municipality of Pará State, Brazil. Moreover, this study aims to investigate the principal risk factors that this community is exposed to. METHODS: The current study has accessed blood samples from 181 volunteers who have answered an epidemiological questionnaire. Analyses on serological markers have been tested with commercial ELISA kits for detecting HBsAg, total anti-HBc, anti-HBs, and anti-HCV. Within seroreactive patients for HCV, RT-PCR and line probe assay have been performed to identify the viral genotype. RESULTS: In the serological marker analysis for hepatitis B, no reactivity for HBsAg, rate of 1.1 percent for total anti-HBc, and rate of 19.3 percent for anti-HBs have been observed. On hepatitis C, 8.8 percent seroprevalence has been found, in which 62.5 percent have gotten viral RNA. Among the risk factors studied, the following have been highlighted: non-use of condoms, sharing of cutting instruments, use of illicit drugs, and reports of family disease with HBV or HCV. CONCLUSIONS: The vaccination coverage against HBV is low, and the high prevalence of HCV within this community has been observed.
INTRODUÇÃO: As hepatites virais constituem um importante problema de saúde pública no mundo. No Brasil existem poucos estudos sobre esta questão, especialmente entre as comunidades ribeirinhas. O objetivo deste estudo foi determinar a soroprevalência das hepatites B e C virais na comunidade ribeirinha da Ilha do Pacuí, no Estado do Pará, Brasil, e investigar os principais fatores de risco principal a que está comunidade está exposta. MÉTODOS: O presente estudo avaliou amostras de sangue de 181 voluntários que responderam a um questionário epidemiológico. Análises de marcadores sorológicos foram testados com kits comerciais de ELISA para detecção de HBsAg, anti-HBc total, anti-HBs e anti-VHC. Nos pacientes reagentes para VHC, RT-PCR e um line probe assay foi realizado para identificar o genótipo viral. RESULTADOS: Na análise dos marcadores sorológicos para hepatite B, observou-se taxas de 1,1 por cento para anti-HBc total e 19,3 por cento para anti-HBs, o marcador sorológico HBsAg não foi encontrado nesta população. Para a hepatite C foi encontrada um soroprevalência de 8,8 por cento, destes 62,5 por cento tinham RNA viral. Entre os fatores de risco estudados se destacaram: a não-utilização de preservativos, o compartilhamento de instrumentos cortantes, uso de drogas ilícitas e relatos de doença na família com VHB ou VHC. CONCLUSÕES: Observamos que a cobertura de vacinação contra o VHB é baixa e uma alta prevalência da hepatite C nesta comunidade.
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Adulto , Femenino , Humanos , Masculino , Hepacivirus , Virus de la Hepatitis B , Hepatitis B/epidemiología , Hepatitis C/epidemiología , Brasil/epidemiología , Brasil/etnología , ADN Viral/sangre , Ensayo de Immunospot Ligado a Enzimas , Genotipo , Hepacivirus/genética , Hepacivirus/inmunología , Anticuerpos contra la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/análisis , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Hepatitis B/diagnóstico , Anticuerpos contra la Hepatitis C/sangre , Hepatitis C/diagnóstico , Reacción en Cadena de la Polimerasa , Prevalencia , ARN Viral/sangre , Población Rural , Factores SocioeconómicosRESUMEN
INTRODUCTION: Although control measures of maternal and congenital syphilis are available in Brazil, difficulties exist within the healthcare network in providing a laboratory diagnosis of the infection during the prenatal period. The objective of this study was to confirm the presence of Treponema pallidum by PCR in women with positive VDRL serology and lethal pregnancy outcomes, i.e., abortion, stillbirth and neonatal death. METHODS: A retrospective study was conducted on VDRLseroreactive women with lethal pregnancy outcomes admitted to the Fundação Santa Casa de Misericórdia do Pará (FSCM-PA) between January and July 2004. Serum samples and DNA from whole blood were obtained at the time of screening by the VDRL test. These samples were analyzed by IgG ELISA, IgM FTA-Abs and simple PCR (polA). RESULTS: During the study period, 0.7% (36/4,912) of women with lethal pregnancy outcomes presented a positive VDRL test. The polAgene was amplified in 72.7% (24/33) of these women, with 55.6% (20/36) and 94.4% (34/36) presenting IgM and IgG antibodies against T. pallidum, respectively. Comparison of these results showed a significant difference, with agreement between the PCR and IgM FTA-Abs results, suggesting that maternal syphilis was an active infection. No basic cause of death of the conceptus was reported in 97.2% (35/36) of cases. Among women who were submitted to the VDRL test during the prenatal period, only four of the nine seroreactive patients underwent treatment. CONCLUSIONS: The high frequency of syphilis in the group studied indicates the fragility of the service of infection diagnosis, treatment and monitoring, compromising epidemiological control.
INTRODUÇÃO: Apesar das medidas de controle da sífilis materna e congênita estarem disponíveis no Brasil, existem dificuldades da rede em prover o diagnóstico laboratorial da infecção durante o pré-natal. O objetivo deste estudo foi confirmar a presença do Treponema pallidum pela PCR em mulheres com sorologia positiva ao VDRL e com resultado letal da gravidez, isto é, aborto, natimorto e neomorto. MÉTODOS: Estudo retrospectivo realizado em mulheres VDRL-sororeativas com resultado negativo da gravidez, admitidas na Fundação Santa Casa de Misericórdia do Pará FSCM-PA entre janeiro e julho de 2004. As amostras de soro e DNA de sangue total foram obtidas no mesmo período da triagem pelo VDRL. Estas amostras foram analisadas pelo ELISA IgG, FTA-Abs IgM e PCR simples (polA). RESULTADOS: Durante o período de estudo, 0,7% (36/4.912) das mulheres com resultado letal da gravidez apresentaram VDRL positivo. O genepolA foi amplificado em 72,7% (24/33) destas mulheres,com 55,6% (20/36) e 94,4% (34/36) apresentando anticorpos tipo IgG e IgM contra o T. pallidum, respectivamente. A comparação destes resultados mostrou uma diferença estatística significativa, sendo que os resultados da PCR versus FTA-Abs Ig Mmostraram-se concordantes, sugerindo que a sífilis materna era uma infecção ativa. A causa básica de morte dos conceptos não foi relatada em 97,2% (35/36) dos casos. Entre as mulheres que foram submetidas ao VDRL no pré-natal, somente quatro das nove soropositivas receberam tratamento. CONCLUSÕES: A elevada frequência de sífilis no grupo de estudo indica a fragilidade do serviço no diagnóstico, tratamento e monitoramento da infecção, comprometendo o controle epidemiológico.
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Femenino , Humanos , Embarazo , Anticuerpos Antibacterianos/sangre , Cardiolipinas/sangre , Colesterol/sangre , Fosfatidilcolinas/sangre , Complicaciones Infecciosas del Embarazo/diagnóstico , Sífilis/diagnóstico , Treponema pallidum/genética , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Reacción en Cadena de la Polimerasa , Resultado del Embarazo , Estudios Retrospectivos , Serodiagnóstico de la Sífilis/métodos , Treponema pallidum/inmunologíaRESUMEN
INTRODUCTION: Although control measures of maternal and congenital syphilis are available in Brazil, difficulties exist within the healthcare network in providing a laboratory diagnosis of the infection during the prenatal period. The objective of this study was to confirm the presence of Treponema pallidum by PCR in women with positive VDRL serology and lethal pregnancy outcomes, i.e., abortion, stillbirth and neonatal death. METHODS: A retrospective study was conducted on VDRLseroreactive women with lethal pregnancy outcomes admitted to the Fundação Santa Casa de Misericórdia do Pará (FSCM-PA) between January and July 2004. Serum samples and DNA from whole blood were obtained at the time of screening by the VDRL test. These samples were analyzed by IgG ELISA, IgM FTA-Abs and simple PCR (polA). RESULTS: During the study period, 0.7% (36/4,912) of women with lethal pregnancy outcomes presented a positive VDRL test. The polAgene was amplified in 72.7% (24/33) of these women, with 55.6% (20/36) and 94.4% (34/36) presenting IgM and IgG antibodies against T. pallidum, respectively. Comparison of these results showed a significant difference, with agreement between the PCR and IgM FTA-Abs results, suggesting that maternal syphilis was an active infection. No basic cause of death of the conceptus was reported in 97.2% (35/36) of cases. Among women who were submitted to the VDRL test during the prenatal period, only four of the nine seroreactive patients underwent treatment. CONCLUSIONS: The high frequency of syphilis in the group studied indicates the fragility of the service of infection diagnosis, treatment and monitoring, compromising epidemiological control.
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Anticuerpos Antibacterianos/sangre , Cardiolipinas/sangre , Colesterol/sangre , Fosfatidilcolinas/sangre , Complicaciones Infecciosas del Embarazo/diagnóstico , Sífilis/diagnóstico , Treponema pallidum/genética , Femenino , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Reacción en Cadena de la Polimerasa , Embarazo , Resultado del Embarazo , Estudios Retrospectivos , Serodiagnóstico de la Sífilis/métodos , Treponema pallidum/inmunologíaRESUMEN
CONTEXT: Gastric neoplasia is the second most common cause of death by cancer in the world and H. pylori is classified as a type I human carcinogen by the World Health Organization. However, despite the high prevalence of infection by H. pylori around the world, less than 3% of individuals carrying the bacteria develop gastric neoplasias. Such a fact indicates that evolution towards malignancy may be associated with bacterial factors in the host and the environment. OBJECTIVES: To investigate the association between polymorphism in the region promoting the IL-8 (-251) gene and the H. pylori genotype, based on the vacA alleles and the presence of the cagA gene, using clinical and histopathological data. METHODS: In a prospective study, a total of 102 patients with stomach cancer and 103 healthy volunteers were analysed. Polymorphism in interleukin 8 (-251) was determined by the PCR-restriction fragment length polymorphism reaction and sequencing. PCR was used for genotyping the vacA alleles and the cagA in the bacterial strains PCR. Gastric biopsies were histologically assessed. RESULTS: The H. pylori serology was positive for 101 (99%) of all patients analysed, and 98 (97%) of them were colonized by only one strain. In patients with monoinfection, 82 (84%) of the bacterial strains observed had the s1b/m1 genotype. The cagA gene was detected in 74 (73%) of patients infected by H. pylori. The presence of the cagA gene was demonstrated as associated with the presence of the s1b/m1 genotype of the vacA gene (P = 0.002). As for polymorphism in the interleukin 8 (-251) gene we observed that the AA (P = 0.026) and AT (P = 0.005) genotypes were most frequent in the group of patients with gastric adenocarcinoma. By comparing the different types of isolated bacterial strains with the interleukin -8 (-251) and the histopathological data we observed that carriers of the A allele (AT and AA) infected by virulent strains (m1s1 cagA+) demonstrated a greater risk of presenting a degree of inflammation (OR = 24.75 CI 95% 2.29-267.20 P = 0.004) and increased neutrophilic activity (OR = 28.71 CI 95% 2.62-314 P = 0.002) in the gastric mucosa. CONCLUSION: Our results demonstrate that the interaction between polymorphism in the interleukin -8 (-251) gene, particularly with carriers of the A allele and the infecting type of H. pylori strain (s1m1 cagA positive) performs an important function in development of gastric adenocarcinoma.
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Adenocarcinoma/microbiología , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , Interleucina-8/genética , Neoplasias Gástricas/microbiología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Genotipo , Infecciones por Helicobacter/complicaciones , Helicobacter pylori/patogenicidad , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Estudios ProspectivosRESUMEN
CONTEXT: Gastric neoplasia is the second most common cause of death by cancer in the world and H. pylori is classified as a type I human carcinogen by the World Health Organization. However, despite the high prevalence of infection by H. pylori around the world, less than 3 percent of individuals carrying the bacteria develop gastric neoplasias. Such a fact indicates that evolution towards malignancy may be associated with bacterial factors in the host and the environment. OBJECTIVES: To investigate the association between polymorphism in the region promoting the IL-8 (-251) gene and the H. pylori genotype, based on the vacA alleles and the presence of the cagA gene, using clinical and histopathological data. METHODS: In a prospective study, a total of 102 patients with stomach cancer and 103 healthy volunteers were analysed. Polymorphism in interleukin 8 (-251) was determined by the PCR-restriction fragment length polymorphism reaction and sequencing. PCR was used for genotyping the vacA alleles and the cagA in the bacterial strains PCR. Gastric biopsies were histologically assessed. RESULTS: The H. pylori serology was positive for 101 (99 percent) of all patients analysed, and 98 (97 percent) of them were colonized by only one strain. In patients with monoinfection, 82 (84 percent) of the bacterial strains observed had the s1b/m1 genotype. The cagA gene was detected in 74 (73 percent) of patients infected by H. pylori. The presence of the cagA gene was demonstrated as associated with the presence of the s1b/m1 genotype of the vacA gene (P = 0.002). As for polymorphism in the interleukin 8 (-251) gene we observed that the AA (P = 0.026) and AT (P = 0.005) genotypes were most frequent in the group of patients with gastric adenocarcinoma. By comparing the different types of isolated bacterial strains with the interleukin -8 (-251) and the histopathological data we observed that carriers of the A allele (AT and AA) infected by virulent strains (m1s1 cagA+) demonstrated a greater risk of presenting a degree of inflammation (OR = 24.75 CI 95 percent 2.29-267.20 P = 0.004) and increased neutrophilic activity (OR = 28.71 CI 95 percent 2.62-314 P = 0.002) in the gastric mucosa. CONCLUSION: Our results demonstrate that the interaction between polymorphism in the interleukin -8 (-251) gene, particularly with carriers of the A allele and the infecting type of H. pylori strain (s1m1 cagA positive) performs an important function in development of gastric adenocarcinoma.
CONTEXTO: A neoplasia gástrica é a segunda causa mais comum de morte por câncer no mundo e o H. pylori é classificado como carcinógeno humano tipo I pela Organização Mundial de Saúde. Entretanto, apesar da elevada prevalência da infecção pelo H. pylori em todo mundo, menos de 3 por cento de indivíduos portadores dessa bactéria desenvolvem neoplasias gástricas. Tal fato indica que a evolução para malignização possa estar associada a fatores bacterianos, do hospedeiro e do ambiente. OBJETIVOS: Investigou-se a associação do polimorfismo da região promotora do gene IL-8 (-251) e do genótipo do H. pylori, baseado nos alelos vacA e na presença do gene cagA, com a clínica e os dados histopatológicos. MÉTODOS: Em estudo prospectivo, 102 pacientes com câncer gástrico e 103 voluntários saudáveis foram analisados. O polimorfismo da IL-8 (-251) foi determinado pela reação de PCR-RFLP e sequenciamento. Para genotipagem dos alelos vacA e do gene cagA das cepas bacterianas foi utilizada a PCR. As biopsias gástricas foram avaliadas histologicamente. RESULTADOS: A sorologia para o H. pylori foi positiva em 101 (99 por cento) de todos os pacientes analisados, e 98 (97 por cento) deles foram colonizados por apenas uma cepa bacteriana. Em pacientes com monoinfecção, 82 (84 por cento) das cepas bacterianas observadas apresentavam o genótipo s1b/m1. O gene cagA foi detectado em 74 (73 por cento) dos pacientes infectados pelo H. pylori. A presença do gene cagA demonstrou estar associada com a presença do genótipo s1b/m1 do gene vacA (P = 0,002). Quanto ao polimorfismo do gene da IL-8 (-251), observou-se que os genótipos AA (P = 0,026) e AT (P = 0,005) foram mais frequentes no grupo de pacientes com adenocarcinoma gástrico. Comparando os diferentes tipos de cepas bacterianas isoladas, com o polimorfismo do gene da IL-8-251 e dados histopatológicos, observou-se que, portadores do alelo A (AT e AA) infectados por cepas virulentas (m1s1 cagA+), demonstraram risco aumentado de apresentar maior grau de inflamação (OR = 24,75 IC 95 por cento 2,29-267,20 P = 0,004) e aumento da atividade neutrofílica (OR = 28,71 IC 95 por cento 2.62-314 P = 0,002) na mucosa gástrica. CONCLUSÃO: Os resultados demonstram que a interação entre o polimorfismo do gene da IL-8, particularmente em portadores do alelo A, e o tipo de cepa infectante do H. pylori (s1m1 cagA positiva) desempenha importante função no desenvolvimento do câncer gástrico.
Asunto(s)
Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adenocarcinoma/microbiología , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , /genética , Neoplasias Gástricas/microbiología , Estudios de Casos y Controles , Genotipo , Infecciones por Helicobacter/complicaciones , Helicobacter pylori/patogenicidad , Polimorfismo Genético , Estudios ProspectivosRESUMEN
Resistance of Helicobacter pylori to clarithromycin is characterised by simple point mutations in the 23S ribosomal RNA (rRNA) gene and is responsible for the majority of cases of failure to eradicate this bacterium. In this paper, we characterised the variability of the 23S rRNA gene in biopsies of patients with gastric pathologies in the eastern Amazon (Northern Region of Brazil) using PCR and sequencing. A total of 49 sequences of H. pylori strains were analysed and of those, 75.6% presented nucleotide substitutions: A2142G (3.3%), T2182C (12.9%), G2224A (6.45%), T2215C (61.3%), A2192G (3.3%), G2204C (6.4%) and T2221C (6.4%). Of the mutations identified, four are known mutations related to cases of resistance and 16.1% are not yet described, revealing a high prevalence of mutations in the H. pylori 23S rRNA gene among the strains circulating in the in the eastern Amazon. The high prevalence in individuals with gastric pathologies in the Northern Region of Brazil demonstrates the need for characterising the profile of these strains to provide correct therapy for patients, considering that mutations in this gene are normally associated with resistance to the primary medication used in controlling H. pylori infection.
Asunto(s)
Farmacorresistencia Bacteriana/genética , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , Mutación Puntual/genética , ARN Ribosómico 23S/genética , Gastropatías/microbiología , Antibacterianos/farmacología , Biopsia , Brasil , Claritromicina/farmacología , Infecciones por Helicobacter/patología , Helicobacter pylori/efectos de los fármacos , Humanos , Reacción en Cadena de la PolimerasaRESUMEN
AIM: To establish whether virulence factor genes vacA and cagA are present in Helicobacter pylori (H. pylori) retrieved from gastric mucosa and dental plaque in patients with dyspepsia. METHODS: Cumulative dental plaque specimens and gastric biopsies were submitted to histological examination, rapid urease test and polymerase chain reaction (PCR) assays to detect the presence of cagA and vacA polymorphisms. RESULTS: Detection of H. pylori from dental plaque and gastric biopsy samples was greater by PCR compared to histological examination and the rapid urease test. DNA from H. pylori was detected in 96% of gastric mucosa samples and in 72% of dental plaque samples. Sixty-three (89%) of 71 dental plaque samples that were H. pylori-positive also exhibited identical vacA and cagA genotypes in gastric mucosa. The most common genotype was vacAs1bm1 and cagA positive, either in dental plaque or gastric mucosa. These virulent H. pylori isolates were involved in the severity of clinical outcome. CONCLUSION: These pathogenic strains were found simultaneously in dental plaque and gastric mucosa, which suggests that gastric infection is correlated with the presence of H. pylori in the mouth.
Asunto(s)
Placa Dental/microbiología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , Helicobacter pylori/aislamiento & purificación , Gastropatías/microbiología , Estómago/microbiología , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Biopsia , Brasil/epidemiología , Gastritis/microbiología , Genotipo , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/epidemiología , Helicobacter pylori/patogenicidad , Humanos , Úlcera Péptica/microbiología , Ureasa/análisisRESUMEN
Resistance of Helicobacter pylori to clarithromycin is characterised by simple point mutations in the 23S ribosomal RNA (rRNA) gene and is responsible for the majority of cases of failure to eradicate this bacterium. In this paper, we characterised the variability of the 23S rRNA gene in biopsies of patients with gastric pathologies in the eastern Amazon (Northern Region of Brazil) using PCR and sequencing. A total of 49 sequences of H. pylori strains were analysed and of those, 75.6 percent presented nucleotide substitutions: A2142G (3.3 percent), T2182C (12.9 percent), G2224A (6.45 percent), T2215C (61.3 percent), A2192G (3.3 percent), G2204C (6.4 percent) and T2221C (6.4 percent). Of the mutations identified, four are known mutations related to cases of resistance and 16.1 percent are not yet described, revealing a high prevalence of mutations in the H. pylori 23S rRNA gene among the strains circulating in the in the eastern Amazon. The high prevalence in individuals with gastric pathologies in the Northern Region of Brazil demonstrates the need for characterising the profile of these strains to provide correct therapy for patients, considering that mutations in this gene are normally associated with resistance to the primary medication used in controlling H. pylori infection.
Asunto(s)
Humanos , Farmacorresistencia Bacteriana/genética , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , Mutación Puntual/genética , /genética , Gastropatías/microbiología , Antibacterianos/farmacología , Biopsia , Brasil , Claritromicina/farmacología , Infecciones por Helicobacter/patología , Helicobacter pylori/efectos de los fármacos , Reacción en Cadena de la PolimerasaRESUMEN
We isolated 44 strains of rapidly growing mycobacteria (RGM) from 19 patients with pulmonary infections assisted at the Instituto Evandro Chagas (Pará, Brazil) from 2004 to 2007. Identification at the species level was performed by PCR restriction fragment length polymorphism analysis (PRA) of a 441 bp hsp65 fragment and partial 16S rRNA, hsp65, and rpoB gene sequencing. Genotyping by PRA yielded 3 digestion patterns: one identical to Mycobacterium abscessus type I (group I); another to M. abscessus type II, Mycobacterium bolletii, and Mycobacterium massiliense (group II); and a third typical for Mycobacterium fortuitum type I (group III). When comparing analysis of the 3 genes, more discrimination was obtained by rpoB gene sequence, which allowed good distinction between group I, II, and III strains and subclassification of group II strains in SG IIa (M. bolletii) and SG IIb (M. massiliense). In this study, we show that the description of new RGM species requires the establishment of standardized procedures for RGM identification and the alert of the clinician about their involvement in pulmonary disease and the necessity of treatment for control and cure.
Asunto(s)
Infecciones por Mycobacterium/microbiología , Mycobacterium/clasificación , Mycobacterium/aislamiento & purificación , Neumonía Bacteriana/microbiología , Proteínas Bacterianas/genética , Brasil , Chaperonina 60/genética , Dermatoglifia del ADN , ADN Bacteriano/química , ADN Bacteriano/genética , ARN Polimerasas Dirigidas por ADN/genética , Humanos , Datos de Secuencia Molecular , Mycobacterium/genética , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Longitud del Fragmento de Restricción , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
The Lewis blood group system involves two major antigens, Leª and Le b. Their antigenic determinants are not primary gene products but are synthesized by the transfer of sugar subunits to a precursory chain by a specific enzyme which is the product of the FUT3 gene (Lewis gene). The presence of three FUT3 gene single nucleotide polymorphisms (SNPs) (59T > G; 508G > A and 1067T > A) was related to the Lewis phenotype of erythrocytes from 185 individuals of Japanese ancestry living in the town of Tomé-Açu in the Brazilian Amazon region. This relationship was detected using a serological hemagglutination test and the Dot-ELISA assay along with the molecular technique PCR-RFLP. We found that the three SNPs investigated in this study only accounted for a proportion of the Lewis-negative phenotype of the erythrocytes.
RESUMEN
We have examined the prevalence of gene cagA and vacA alleles in 129 patients, 69 with gastritis and 60 with peptic ulcer diseases from North Brazil and their relation with histopathological data. vacA and cagA genotype were determined by polymerase chain reaction. Hematoxylin-eosin staining was used for histological diagnosis. 96.6 percent of the patients were colonized by Helicobacter pylori strains harboring single vacA genotype (nont-mixed infection). Among them, 11.8 percent had subtype s1a, 67.8 percent had subtype s1b, and 17 percent subtype s2. In regard to the middle region analysis, m1 alleles were found in 75.4 percent and m2 in 21.2 percent of patients. The cagA gene was detected in 78 percent patients infected with H. pylori and was associated with the s1-m1 vacA genotype. The H. pylori strains, vacA s1b m1/cagA-positive, were associated with increased risk of peptic ulcer disease and higher amounts of lymphocytic and neutrophilic infiltrates and the presence of intestinal metaplasia. These findings show that cagA and vacA genotyping may have clinical relevance in Brazil.
Asunto(s)
Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Gastritis/microbiología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , Úlcera Péptica/microbiología , Alelos , Brasil , ADN Bacteriano/análisis , Genotipo , Gastritis/patología , Infecciones por Helicobacter/patología , Reacción en Cadena de la Polimerasa , Úlcera Péptica/patologíaRESUMEN
We have examined the prevalence of gene cagA and vacA alleles in 129 patients, 69 with gastritis and 60 with peptic ulcer diseases from North Brazil and their relation with histopathological data. vacA and cagA genotype were determined by polymerase chain reaction. Hematoxylin-eosin staining was used for histological diagnosis. 96.6% of the patients were colonized by Helicobacter pylori strains harboring single vacA genotype (nont-mixed infection). Among them, 11.8% had subtype s1a, 67.8% had subtype s1b, and 17% subtype s2. In regard to the middle region analysis, m1 alleles were found in 75.4% and m2 in 21.2% of patients. The cagA gene was detected in 78% patients infected with H. pylori and was associated with the s1-m1 vacA genotype. The H. pylori strains, vacA s1b m1/cagA-positive, were associated with increased risk of peptic ulcer disease and higher amounts of lymphocytic and neutrophilic infiltrates and the presence of intestinal metaplasia. These findings show that cagA and vacA genotyping may have clinical relevance in Brazil.
Asunto(s)
Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Gastritis/microbiología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , Úlcera Péptica/microbiología , Adolescente , Adulto , Anciano , Alelos , Brasil , ADN Bacteriano/análisis , Femenino , Gastritis/patología , Genotipo , Infecciones por Helicobacter/patología , Humanos , Masculino , Persona de Mediana Edad , Úlcera Péptica/patología , Reacción en Cadena de la PolimerasaRESUMEN
Helicobacter pylori is a pathogenic agent with a worldwide distribution and is involved in the development of many gastrointestinal diseases. Nowadays infection with the virulent strain CagA+ of H. pylori is considered one of the main etiological factors in the development of gastric ulcer. Based on this information, we investigated the seroprevalence of virulent strains among patients with gastric ulcer from one region, using serologic tests to detect antibodies against H. pylori and CagA protein. Infection by the virulent strain was found in 82% (40/55) of the patients, and among these, 89% (40/45) presented an increased degree of inflammation in the gastric mucosa, with a dense infiltration of leukocytes in the tissue, which probably favored the formation of gastric ulcer. We concluded that the presence of the virulent strain is related to the development of an increased inflammation in the gastric mucosa.