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1.
Mem Inst Oswaldo Cruz ; 106(6): 748-54, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22012231

RESUMO

The hypothesis that Helicobactermight be a risk factor for human liver diseases has arisen after the detection of Helicobacter DNA in hepatic tissue of patients with hepatobiliary diseases. Nevertheless, no explanation that justifies the presence of the bacterium in the human liver has been proposed. We evaluated the presence of Helicobacterin the liver of patients with hepatic diseases of different aetiologies. We prospectively evaluated 147 patients (106 with primary hepatic diseases and 41 with hepatic metastatic tumours) and 20 liver donors as controls. Helicobacter species were investigated in the liver by culture and specific 16S rDNA nested-polymerase chain reaction followed by sequencing. Serum and hepatic levels of representative cytokines of T regulatory cell, T helper (Th)1 and Th17 cell lineages were determined using enzyme linked immunosorbent assay. The data were evaluated using logistic models. Detection of Helicobacter pylori DNA in the liver was independently associated with hepatitis B virus/hepatitis C virus, pancreatic carcinoma and a cytokine pattern characterised by high interleukin (IL)-10, low/absent interferon-γ and decreased IL-17A concentrations (p < 10(-3)). The bacterial DNA was never detected in the liver of patients with alcoholic cirrhosis and autoimmune hepatitis that are associated with Th1/Th17 polarisation. H. pylori may be observed in the liver of patients with certain hepatic and pancreatic diseases, but this might depend on the patient cytokine profile.


Assuntos
Citocinas/imunologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/isolamento & purificação , Hepatopatias/microbiologia , Fígado/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Feminino , Helicobacter pylori/genética , Humanos , Imuno-Histoquímica , Hepatopatias/imunologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Estudos Prospectivos , Células Th1/imunologia , Células Th17/imunologia , Adulto Jovem
2.
Microbes Infect ; 10(14-15): 1477-83, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18809506

RESUMO

Helicobacter pylori infection is mainly acquired in childhood, and polymorphisms in the host genes coding for Toll-like receptors (TLRs) may influence the innate and adaptive immune response to the infection, affecting the susceptibility to H. pylori or the disease outcomes. Our aim was to investigate whether TLR4, TLR2, and TLR5 polymorphisms were associated with H. pylori susceptibility and risk for duodenal ulcer in children. Gastric biopsy specimens were obtained at endoscopy for evaluation of H. pylori status, TLR4, TLR2 and TLR5 polymorphisms from 486 children (254 H. pylori-negative and 232 H. pylori-positive: 72 with and 160 without duodenal ulcer). cagA status of H. pylori infection was investigated by PCR. The levels of gastric cytokines were detected by ELISA. H. pylori-positivity or duodenal ulcer were not associated with TLR2, TLR4 or TLR5 polymorphisms. Otherwise, the presence of TLR4 polymorphic allele was associated with infection by cagA-positive strains and with increased gastric levels of interleukin-8 and interleukin-10. TLR4 polymorphism might ultimately contribute to more severe consequences of the infection in adulthood since it was associated with susceptibility to cagA-positive H. pylori infection early in life.


Assuntos
Úlcera Duodenal/genética , Úlcera Duodenal/microbiologia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/genética , Helicobacter pylori/imunologia , Polimorfismo Genético , Receptores Toll-Like/genética , Adolescente , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Criança , Pré-Escolar , Citocinas/análise , Suscetibilidade a Doenças , Úlcera Duodenal/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Mucosa Gástrica/química , Mucosa Gástrica/imunologia , Infecções por Helicobacter/imunologia , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase , Fatores de Risco , Fatores de Virulência/genética
3.
Inflamm Bowel Dis ; 15(3): 353-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18942754

RESUMO

BACKGROUND: Polymorphisms in genes linked to the innate and adaptive immune response may be involved in inflammatory bowel disease pathogenesis. Our aim was to investigate associations among IL1B-511, IL1B-31, IL1RN, TNFA-307, TLR-2, TLR-4, IL2-330, NOD2 G908R, NOD2 L1007fsinsC polymorphisms and both Crohn's disease (CD) and ulcerative colitis (UC) in a Brazilian population. METHODS: We studied 43 patients with CD, 42 with UC, and 541 blood donors. Polymorphisms were evaluated by PCR, PCR-CTPP, or PCR-RFLP. Data were analyzed in multivariate models adjusting for confounding factors. RESULTS: IL1RN VNTR (P = 0.00, odds ratio [OR] = 2.43, 95% confidence interval [CI] = 1.50-3.90), as well as TNFA-307 polymorphic allele (P = 0.05, OR = 1.70, 95% CI = 1.00-2.94) were associated with UC. Both NOD2 mutations (G908R, P = 0.02, OR = 6.83, 95% CI = 1.62-25.45, and L1007fsinsC, P = 0.00, OR = 20.00, 95% CI = 3.21-124.69) were associated with CD. CONCLUSIONS: Our analyses showed positive associations between proinflammatory polymorphisms at IL1RN and TNFA-307 loci and UC, as well as polymorphisms in the NOD2 gene and CD. These results highlight the importance of different genetic profiles associated with CD and UC.


Assuntos
Colite Ulcerativa/imunologia , Doença de Crohn/imunologia , DNA/genética , Imunidade Celular/imunologia , Proteína Adaptadora de Sinalização NOD2/genética , Polimorfismo Genético , Adulto , Alelos , Brasil/epidemiologia , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/genética , Doença de Crohn/epidemiologia , Doença de Crohn/genética , Feminino , Seguimentos , Genótipo , Humanos , Proteína Antagonista do Receptor de Interleucina 1/genética , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Desequilíbrio de Ligação , Masculino , Proteína Adaptadora de Sinalização NOD2/metabolismo , Reação em Cadeia da Polimerase , Prevalência , Estudos Retrospectivos
4.
Mem. Inst. Oswaldo Cruz ; 106(6): 748-754, Sept. 2011. ilus
Artigo em Inglês | LILACS | ID: lil-602060

RESUMO

The hypothesis that Helicobactermight be a risk factor for human liver diseases has arisen after the detection of Helicobacter DNA in hepatic tissue of patients with hepatobiliary diseases. Nevertheless, no explanation that justifies the presence of the bacterium in the human liver has been proposed. We evaluated the presence of Helicobacterin the liver of patients with hepatic diseases of different aetiologies. We prospectively evaluated 147 patients (106 with primary hepatic diseases and 41 with hepatic metastatic tumours) and 20 liver donors as controls. Helicobacter species were investigated in the liver by culture and specific 16S rDNA nested-polymerase chain reaction followed by sequencing. Serum and hepatic levels of representative cytokines of T regulatory cell, T helper (Th)1 and Th17 cell lineages were determined using enzyme linked immunosorbent assay. The data were evaluated using logistic models. Detection of Helicobacter pylori DNA in the liver was independently associated with hepatitis B virus/hepatitis C virus, pancreatic carcinoma and a cytokine pattern characterised by high interleukin (IL)-10, low/absent interferon-γ and decreased IL-17A concentrations (p < 10-3). The bacterial DNA was never detected in the liver of patients with alcoholic cirrhosis and autoimmune hepatitis that are associated with Th1/Th17 polarisation. H. pylori may be observed in the liver of patients with certain hepatic and pancreatic diseases, but this might depend on the patient cytokine profile.


Assuntos
Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Citocinas/imunologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/isolamento & purificação , Hepatopatias/microbiologia , Fígado/microbiologia , Estudos de Casos e Controles , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Helicobacter pylori/genética , Imuno-Histoquímica , Hepatopatias/imunologia , Reação em Cadeia da Polimerase , Estudos Prospectivos , Células Th1/imunologia , /imunologia
5.
Int J Cancer ; 115(5): 678-83, 2005 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-15704154

RESUMO

Helicobacter pylori cagA-positive strains and host cytokine proinflammatory polymorphisms have been associated with gastric carcinoma. However, the individual role of each factor has not been evaluated yet. Our aim was to evaluate whether IL-1 gene cluster and tumor necrosis factor-alpha (TNFA)-307 polymorphisms, as well as cagA-positive status, are associated with gastric carcinoma in a non-Caucasian population by analyzing the data in logistic regression models. We evaluated 166 patients with noncardia gastric carcinoma and 541 blood donors. Among them, 702 were successfully genotyped for all cytokine studied: 166 with gastric carcinoma and 536 controls. The carcinoma patients were considered to be H. pylori-positive if culture alone or 2 among preformed urease test, stained smear or histologic section, serology, polymerase chain reaction (PCR) for ureA and urea breath test were positive. In blood donors, H. pylori status was based on enzyme-linked immunosorbent assay. The cagA status was determined by PCR or serology. IL1B-511/-31, IL1RN (interleukin-1 receptor antagonist) and TNFA-307 polymorphisms were genotyped by PCR, PCR with restriction fragment length polymorphism, or PCR with confronting 2-pair primers. We found that the IL1RN2 polymorphic allele (OR = 1.93) was associated with noncardia gastric carcinoma, even after inclusion of age, gender and cagA status in the logistic models. However, the cagA-positive status was the strongest independent factor associated with gastric carcinoma (OR = 11.89). The other polymorphisms were not significantly associated with the disease when they were evaluated in logistic models. This study provides evidence supporting the independent associations of cagA-positive H. pylori status and IL1RN polymorphisms with noncardia gastric carcinoma.


Assuntos
Antígenos de Bactérias/análise , Proteínas de Bactérias/análise , Carcinoma/genética , Infecções por Helicobacter/complicações , Polimorfismo Genético , Sialoglicoproteínas/genética , Neoplasias Gástricas/genética , Adulto , Idoso , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Carcinoma/patologia , Estudos de Casos e Controles , Feminino , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco , Neoplasias Gástricas/patologia
6.
Pediatr Res ; 58(5): 892-6, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16183821

RESUMO

Duodenal ulcers in children are associated with Helicobacter pylori gastric infection with cagA-positive strains, but factors linked to the host are poorly known. The authors evaluated the role of proinflammatory interleukin-1 gene cluster polymorphisms in the pathogenesis of duodenal ulcer. They studied prospectively 437 children 1 to years old, 209 of whom were H. pylori positive and 228 of whom were H. pylori negative. IL1B-511-C/T, -31T/C, and IL1RN Variable number of tandem repeats were genotyped by polymerase chain reaction (PCR) restriction fragment length polymorphism, PCR with confronting two-pair primers, and PCR, respectively. cagA status was evaluated by PCR. The role of the proinflammatory cytokine genotypes in the genesis of duodenal ulcer was evaluated before and after stratification of H. pylori status on logistic regression models. In the group of children without duodenal ulcer, no association was observed between H. pylori status and proinflammatory polymorphisms. Furthermore, no association between IL1 cluster genotypes and cagA status was seen in the H. pylori-positive children. However, increasing age, male sex, and IL1RN*2 were independently associated with duodenal ulcer. After stratification, in the H. pylori-positive children, increasing age, male sex, the presence of ILRN*2 allele, and cagA-positive status were independently associated with duodenal ulcer. The risk for the development of duodenal ulcer increased when a combined association of the presence of IL1RN*2 allele and infection by a cagA-positive H. pylori strain was the variable. This study provides evidence supporting independent roles of IL1RN*2 allele and cagA-positive status in the genesis of duodenal ulcer in children.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Úlcera Duodenal/genética , Úlcera Duodenal/microbiologia , Helicobacter pylori/patogenicidade , Polimorfismo Genético , Sialoglicoproteínas/genética , Adolescente , Criança , Pré-Escolar , Feminino , Helicobacter pylori/genética , Humanos , Lactente , Proteína Antagonista do Receptor de Interleucina 1 , Desequilíbrio de Ligação , Masculino , Família Multigênica , Virulência
7.
J Clin Microbiol ; 41(12): 5615-8, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14662950

RESUMO

The presence of Helicobacter DNA species has been investigated in the biliary epithelium of patients with biliary diseases. However, conflicting results have been observed that may have been due to the small number of subjects studied, difficulty in obtaining a healthy control group, absence of controlling for confounding factors, or differences among populations. Therefore, we investigated the presence of Helicobacter species by culture and nested PCR of 16S rRNA genes in gallbladder tissue and bile from 46 Brazilian subjects with and 18 without cholelithiasis. The control group was mainly composed of liver donors and of patients who had submitted to cholecystectomy as part of the surgical treatment for morbid obesity. No Helicobacter species were grown from the bile or gallbladder tissues. Helicobacter DNA was detected in the gallbladder tissue and bile from 31.3 and 42.9% of the patients, respectively. In a logistic regression model, cholelithiasis was positively and independently associated with the female gender (P = 0.02), increasing age (P = 0.002), and the presence of Helicobacter DNA in the gallbladder tissue (P = 0.009). The presence of Helicobacter DNA in the bile was not associated with cholelithiasis (P = 0.8). A significant association between the presence of Helicobacter DNA in the gallbladder epithelium and histological cholecystitis, even after adjusting for gender and age (P = 0.002), was also observed. The sequences of the 16S rRNA genes were >99% similar to that of Helicobacter pylori. In conclusion, our results support the hypothesis that Helicobacter is associated with the pathogenesis of human cholelithiasis and cholecystitis.


Assuntos
Colecistite/microbiologia , Colelitíase/microbiologia , Vesícula Biliar/microbiologia , Helicobacter/isolamento & purificação , Adulto , Idoso , Bile/microbiologia , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/genética , Feminino , Helicobacter/classificação , Helicobacter/genética , Infecções por Helicobacter/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , RNA Bacteriano/genética , RNA Ribossômico 16S/genética
8.
Gastroenterology ; 127(1): 73-9, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15236174

RESUMO

BACKGROUND & AIMS: Proinflammatory interleukin (IL)-1 gene polymorphisms associated with high levels of IL-1beta activity increase the risk for hypochlorhydria and distal gastric carcinoma. The aim of this study was to evaluate whether carriers of these polymorphic genes are protected against gastroesophageal reflux disease (GERD). TNFA-308 polymorphisms were also studied. METHODS: We prospectively evaluated 385 patients without gastric cancer and peptic ulcer. Of these patients, 383 (98 with GERD and 285 controls) were successfully genotyped for all cytokines studied. The cagA status of Helicobacter pylori isolates was determined by polymerase chain reaction (PCR). IL1B-511/-31, IL1RN, and TNFA-308 polymorphisms were genotyped by PCR, PCR/restriction fragment length polymorphism, or PCR/confronting 2-pair primers. Histologic gastritis was assessed according to the updated Sydney system. The role of the proinflammatory cytokine genotypes in the genesis of GERD was evaluated before and after stratification by H. pylori status in logistic regression models controlling for confounding factors. RESULTS: IL1B-31 (a near-complete linkage disequilibrium between polymorphism at -31 and -511 was found) and IL1RN*2 allele polymorphisms were associated with GERD. After stratification, in the group of H. pylori-positive patients, cagA-positive status, IL1B-31 polymorphic alleles, IL1RN*2 alleles, and the degree of corpus gastritis were negatively associated with GERD. In the H. pylori-negative group, IL1B-31C/C genotype was inversely associated with GERD even after adjustment for age and sex. CONCLUSIONS: This study provides evidence supporting the independent protective role of cagA-positive H. pylori status and IL1B and ILRN allele polymorphisms against GERD.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Refluxo Gastroesofágico/genética , Infecções por Helicobacter/genética , Interleucina-1/genética , Sialoglicoproteínas/genética , Adulto , Refluxo Gastroesofágico/complicações , Refluxo Gastroesofágico/prevenção & controle , Infecções por Helicobacter/complicações , Heterozigoto , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Polimorfismo Genético , Estudos Prospectivos , Risco , Fator de Necrose Tumoral alfa/genética
10.
Rev. Soc. Bras. Med. Trop ; 25(4): 247-50, out.-dez. 1992.
Artigo em Inglês | LILACS | ID: lil-141220

RESUMO

Diferentes amostras de leishmania foram analisadas quanto à susceptibilidade in vitro ao pentostam - uma cepa de L. (V) braziliensis considerada sensível ao glucantine, três cepas (duas L. (V) braziliensis e uma L. (L) amazonensis) consideradas naturalmente resistentes ao glucantine, uma linhagem resitente (L. (V) guyanensis) selecionada in vitro pela exposiçäo em alta concentraçäo de droga. A elevada sensibilidade destas amostras em contraposiçäo à resistência observada para a glucantine sugere existir relaçäo entre a estrutura química e a atividade destes compostos. Estes dados indicam a necessidade de uma avaliaçäo comparativa de atividade clínica do pentostam e do glucantime no tratamento da leishamniose


Assuntos
Animais , Gluconato de Antimônio e Sódio/farmacologia , Antimônio/antagonistas & inibidores , Antiprotozoários/antagonistas & inibidores , Compostos Organometálicos/antagonistas & inibidores , Leishmania/efeitos dos fármacos , Meglumina/antagonistas & inibidores , Relação Dose-Resposta a Droga , Especificidade da Espécie , Leishmania braziliensis/efeitos dos fármacos , Leishmania braziliensis/crescimento & desenvolvimento , Leishmania guyanensis/efeitos dos fármacos , Leishmania guyanensis/crescimento & desenvolvimento , Leishmania/crescimento & desenvolvimento , Resistência a Medicamentos
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