RESUMO
The mechanism by which Helicobacter pylori, a noninvasive bacterium, initiates chronic antral gastritis in humans is unknown. We now show that H. pylori releases products with chemotactic activity for monocytes and neutrophils. This chemotactic activity was inhibited by antisera to either H. pylori whole bacteria or H. pylori-derived urease. Moreover, surface proteins extracted from H. pylori and purified H. pylori urease (a major component of the surface proteins) exhibited dose-dependent, antibody-inhibitable chemotactic activity. In addition, a synthetic 20-amino acid peptide from the NH2-terminal portion of the 61-kD subunit, but not the 30-kD subunit, of urease exhibited chemotactic activity for monocytes and neutrophils, localizing the chemotactic activity, at least in part, to the NH2 terminus of the 61-kD subunit of urease. The ability of leukocytes to chemotax to H. pylori surface proteins despite formyl-methionyl-leucyl-phenylalanine (FMLP) receptor saturation, selective inhibition of FMLP-mediated chemotaxis, or preincubation of the surface proteins with antiserum to FMLP indicated that the chemotaxis was not FMLP mediated. Finally, we identified H. pylori surface proteins and urease in the lamina propria of gastric antra from patients with H. pylori-associated gastritis but not from uninfected subjects. These findings suggest that H. pylori gastritis is initiated by mucosal absorption of urease, which expresses chemotactic activity for leukocytes by a mechanism not involving N-formylated oligopeptides.
Assuntos
Proteínas da Membrana Bacteriana Externa/imunologia , Quimiotaxia de Leucócito/imunologia , Mucosa Gástrica/microbiologia , Helicobacter pylori/imunologia , Anticorpos Antibacterianos/imunologia , Mucosa Gástrica/imunologia , Gastrite/imunologia , Gastrite/microbiologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/enzimologia , Humanos , Monócitos/imunologia , N-Formilmetionina Leucil-Fenilalanina/imunologia , Neutrófilos/imunologia , Antro Pilórico/imunologia , Urease/imunologiaRESUMO
The purpose of this study was to assess the role of Helicobacter pylori and several genetic polymorphisms in relation to inflammatory bowel disease (IBD). We studied 44 unrelated patients with IBD and 75 subjects with no history of IBD as controls. Using pyrosequencing technology, we identified gene polymorphisms in IL-10, TNF-A, ILB-31, and TLR4. H. pylori status was determined by serology. Individuals homozygous for IL10-592 A or IL10-1082 A genotypes show significantly lower occurrence of IBD (P=0.03 and P<0.01, respectively). Individuals heterozygous at IL10-1082 have significantly increased occurrence of IBD, both ulcerative colitis and Crohn's disease (P<0.01). There was no difference in the prevalence of H. pylori infection between cases and controls. This study provides evidence that variation in IL10 is correlated with IBD occurrence in this Mexican population.
Assuntos
Doenças Inflamatórias Intestinais/epidemiologia , Doenças Inflamatórias Intestinais/genética , Adulto , Idoso , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/genética , Doença de Crohn/epidemiologia , Doença de Crohn/genética , Feminino , Predisposição Genética para Doença , Haplótipos , Infecções por Helicobacter/complicações , Helicobacter pylori , Humanos , Doenças Inflamatórias Intestinais/complicações , Interleucina-10/genética , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Adulto JovemRESUMO
BACKGROUND: Gastro-oesophageal reflux disease complications may reflect imbalances between protective and injurious factors. Through its effects on cell growth, leptin may influence oesophageal mucosal homeostasis. AIMS: To determine whether leptin receptors are present in the oesophagus, and whether serum or gastric leptin levels are associated with oesophageal inflammation and metaplasia. METHODS: From patients referred for upper endoscopy, biopsies were obtained from the stomach and distal oesophagus, and serum samples were collected. Patients were classified as having normal, inflamed or Barrett's oesophagus. Quantitative immunohistochemistry was performed on representative sections, and leptin levels in plasma and gastric biopsy samples were determined by specific immunoassay. RESULTS: Of 269 individuals enrolled, 105 were Helicobacter pylori-negative. Of the 88 patients with complete oesophageal biopsies, 44 were normal, 24 were inflamed and 20 were Barrett's oesophagus. Receptors for leptin were highly expressed on oesophageal epithelial cells, with similar density and staining pattern in all three conditions, and plasma and antral leptin levels did not differ significantly. Patients with Barrett's had significantly (p = 0.01) higher fundic leptin levels (median 202 (interquartile range 123-333) pg/mg) compared with normal (126 (78-221) pg/mg) or inflamed (114 (76-195) pg/mg) oesophagus. In multivariate analysis, for every twofold increase in fundic leptin, the odds of having Barrett's was 3.4 times (95% CI 1.5 to 7.6) higher compared with having a normal oesophagus. CONCLUSIONS: Leptin receptor expression on oesophageal epithelial cells provides a pathway for leptin-mediated signal transduction. Variation in gastric leptin production could contribute to differential oesophageal healing and metaplasia progression.
Assuntos
Esôfago de Barrett/metabolismo , Esofagite/metabolismo , Esôfago/metabolismo , Refluxo Gastroesofágico/metabolismo , Leptina/metabolismo , Receptores para Leptina/metabolismo , Esôfago de Barrett/etiologia , Esôfago de Barrett/patologia , Endoscopia do Sistema Digestório , Esofagite/patologia , Esôfago/patologia , Feminino , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Refluxo Gastroesofágico/complicações , Refluxo Gastroesofágico/patologia , Humanos , Masculino , Metaplasia/etiologia , Metaplasia/metabolismo , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
Although the intestinal microbiome has been increasingly implicated in autoimmune diseases, much is unknown about its roles in Multiple Sclerosis (MS). Our aim was to compare the microbiome between treatment-naïve MS subjects early in their disease course and controls, and between Caucasian (CA), Hispanic (HA), and African American (AA) MS subjects. From fecal samples, we performed 16S rRNA V4 sequencing and analysis from 45 MS subjects (15 CA, 16 HA, 14 AA) and 44 matched healthy controls, and whole metagenomic shotgun sequencing from 24 MS subjects (all newly diagnosed, treatment-naïve, and steroid-free) and 24 controls. In all three ethnic groups, there was an increased relative abundance of the same single genus, Clostridium, compared to ethnicity-matched controls. Analysis of microbiota networks showed significant changes in the network characteristics between combined MS cohorts and controls, suggesting global differences not restricted to individual taxa. Metagenomic analysis revealed significant enrichment of individual species within Clostridia as well as particular functional pathways in the MS subjects. The increased relative abundance of Clostridia in all three early MS cohorts compared to controls provides candidate taxa for further study as biomarkers or as etiologic agents in MS.
Assuntos
Etnicidade , Microbioma Gastrointestinal , Esclerose Múltipla/microbiologia , Adulto , Negro ou Afro-Americano , Estudos de Casos e Controles , Clostridium/classificação , Clostridium/genética , Clostridium/isolamento & purificação , Feminino , Microbioma Gastrointestinal/genética , Hispânico ou Latino , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Masculino , Metagenoma , Pessoa de Meia-Idade , Esclerose Múltipla/imunologia , RNA Ribossômico 16S/genética , População Branca , Adulto JovemRESUMO
The inflammatory lesions associated with Helicobacter pylori gastritis and duodenitis contain large numbers of mononuclear cells. The close proximity of H. pylori to gastric mucosa suggests that the organism interacts with mononuclear cells, thereby modulating the inflammatory response. To investigate the role of monocytes/macrophages in this response, we examined the effect of whole H. pylori bacteria, H. pylori surface proteins, and H. pylori lipopolysaccharide (LPS) on purified human monocytes. Whole H. pylori and the extracted LPS induced expression of the monocyte surface antigen HLA-DR and interleukin-2 receptors, production of the inflammatory cytokines interleukin 1 and tumor necrosis factor (peptide and messenger RNA), and secretion of the reactive oxygen intermediate superoxide anion. Since H. pylori in vivo does not invade mucosal tissue, we determined whether soluble constituents of the bacteria could activate monocytes. Soluble H. pylori surface proteins, which are enriched for urease and do not contain LPS, stimulated phenotypic, transcriptional, and functional changes consistent with highly activated monocytes. These findings indicate that H. pylori is capable of activating human monocytes by an LPS-independent as well as an LPS-dependent mechanism. H. pylori activation of resident lamina propria macrophages and monocytes trafficking through the mucosa, leading to the secretion of increased amounts of inflammatory cytokines and reactive oxygen intermediates, could play an important role in mediating the inflammatory response associated with H. pylori gastritis and duodenitis.
Assuntos
Helicobacter pylori/imunologia , Ativação de Macrófagos , Monócitos/imunologia , Northern Blotting , Expressão Gênica/efeitos dos fármacos , Antígenos HLA-DR/análise , Humanos , Técnicas In Vitro , Interleucina-1/genética , Interleucina-1/metabolismo , Mucosa Intestinal/imunologia , Lipopolissacarídeos/imunologia , Receptores de Interleucina-2/análise , Superóxidos/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
OBJECTIVE: to assess the efficacy of rabeprazole (RPZ), amoxicillin (Am), and clarithromycin (Cla) (7 vs. 14 days) in the eradication of H. pylori, and to determine the effect of strain-specific antibiotic resistance and host CYP2C19 status. MATERIAL AND METHODS: first, we determined the CYP2C19 status of 100 healthy subjects to establish a sample size for the clinical trial. Then, 59 H. pylori-infected patients were randomized to receive RPZ (20 mg daily) plus Cla (500 mg b.d.) and Am (1,000 mg b.d.) for 7 vs. 14 days. The MIC for Am and Cla were determined using the agar dilution method. The CYP2C19 genotype was determined by the PCR-RFLP method. RESULTS: In the per-protocol analysis (PP) eradication rates were 89.7 and 72% for the 7- and 14-day groups (p = 0.159). In the intention to-treat analysis (ITT) eradication rates were 86.7 and 62.1% in the 7- and 14-day groups, respectively (p = 0.06). None of the strains was resistant to Am, and 4 strains were resistant to Cla: 3 (11.1%) in the 14-day group and 1 (4%) in the 7-day group. Neither strain-specific antibiotic resistance nor host CYP2C19 status influenced eradication rates. CONCLUSIONS: both 7- and 14-day therapies were effective for H. pylori eradication. Strain resistance and CYP2C19 status do not seem to influence eradication rates in the studied population.
Assuntos
2-Piridinilmetilsulfinilbenzimidazóis/uso terapêutico , Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Antiulcerosos/uso terapêutico , Hidrocarboneto de Aril Hidroxilases , Claritromicina/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Oxigenases de Função Mista , 2-Piridinilmetilsulfinilbenzimidazóis/administração & dosagem , 2-Piridinilmetilsulfinilbenzimidazóis/farmacologia , Adulto , Amoxicilina/administração & dosagem , Amoxicilina/farmacologia , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Antiulcerosos/administração & dosagem , Antiulcerosos/farmacologia , Hidrocarboneto de Aril Hidroxilases/genética , Claritromicina/administração & dosagem , Claritromicina/farmacologia , Citocromo P-450 CYP2C19 , Interpretação Estatística de Dados , Farmacorresistência Bacteriana , Quimioterapia Combinada , Feminino , Genótipo , Helicobacter pylori/efeitos dos fármacos , Humanos , Masculino , Testes de Sensibilidade Microbiana , Oxigenases de Função Mista/genética , Rabeprazol , Fatores de TempoRESUMO
BACKGROUND: Infection with Helicobacter pylori is a major risk factor for the development of atrophic gastritis and gastric cancer. H. pylori strains can differ with respect to the presence of cagA (cytotoxin-associated gene A), a gene encoding a high-molecular-weight immunodominant antigen. H. pylori strains possessing cagA have been associated with enhanced induction of acute gastric inflammation. PURPOSE: We investigated the relationship between cagA status and the development of atrophic gastritis in a cohort of subjects infected with H. pylori. METHODS: Gastrointestinal endoscopy with biopsy sampling was used to study the natural history of gastritis in 58 subjects infected with H. pylori. Biopsy specimens were obtained before and after a mean follow-up period of 11.5 years (range, 10-13 years). The cagA status of each individual was determined at the follow-up visit with the use of an enzyme-linked immunosorbent assay designed to detect the presence of serum immunoglobulin G directed against the CagA protein. Two-sided Fisher's exact tests, McNemar's tests, Student's t tests, and Wilcoxon sum rank tests were used to analyze the data. RESULTS: Twenty-four (41%) of the 58 evaluated subjects had serum antibodies against CagA (i.e., they were cagA positive), and 34 subjects were cagA negative. At the initial visit, moderate to severe atrophic gastritis was observed in eight (33%) of the cagA-positive subjects and in six (18%) of the cagA-negative subjects. At that time, positive cagA status and gastric atrophy were not significantly related (P = .22; Fisher's exact test; odds ratio [OR] 2.33; 95% confidence interval [CI] = 0.58-9.65). During follow-up, 16 (36%) of the 44 initially atrophy-negative subjects developed atrophic gastritis (eight [50%] of 16 cagA-positive subjects versus eight [29%] of 28 cagA-negative subjects; P = .20, Fisher's exact test; relative risk [RR] = 1.75; 95% CI = 0.82-3.76). In six of these 16 subjects (five cagA positive versus one cagA negative), atrophic gastritis was accompanied by the development of intestinal metaplasia (i.e., a change in the type of specialized cells present) (P = .02; Fisher's exact test; RR = 9.06; 95% CI = 1.16-71.0). One of the initially atrophy-negative, cagA-positive subjects developed early gastric cancer. Four (29%) of the 14 subjects initially diagnosed with atrophic gastritis showed regression of atrophy during follow-up (one cagA positive and three cagA negative). Therefore, at the end of follow-up, 15 (62%) of the 24 cagA-positive subjects had atrophic gastritis compared with 11 (32%) of the 34 cagA-negative subjects (P = .02; Fisher's exact test; OR = 3.48; 95% CI = 1.02-12.18). CONCLUSION: Infection with cagA-positive H. pylori strains is associated with an increased risk for the eventual development of atrophic gastritis and intestinal metaplasia.
Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Gastrite Atrófica/microbiologia , Genes Bacterianos , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Adulto , Idoso , Estudos de Coortes , Gastrite Atrófica/complicações , Infecções por Helicobacter/complicações , Helicobacter pylori/imunologia , Helicobacter pylori/patogenicidade , Humanos , Pessoa de Meia-Idade , Neoplasias Gástricas/etiologiaRESUMO
Helicobacter pylori infection, thought to be causally related to chronic gastritis, may also be associated with an increased risk of gastric cancer. To determine whether an association with gastric cancer does exist, we retrospectively evaluated serum samples from 69 patients with histologically confirmed gastric adenocarcinoma (32 with cancer at the cardia and 37 with cancer at other sites) and from 218 patients with one of three categories of nongastric cancers, with other gastric cancers, or with benign gastric neoplasms. These samples were compared with samples from 252 cancer-free control subjects, a group comprising 76 asymptomatic volunteers and 176 persons with nonmalignant disorders. Serum samples collected from cancer patients prior to surgery and from cancer-free controls were tested for antibodies to H. pylori by using a highly sensitive and specific IgG enzyme-linked immunosorbent assay. The risk of H. pylori infection in the case patients relative to the control subjects was estimated with the use of multivariate logistic regression analysis to adjust for potential confounding variables. Antibodies to H. pylori were detected in 65% of the patients with noncardia gastric cancer but in only 38% of the patients with gastric cancer located at the cardia. A significant association was found between H. pylori infection and noncardia gastric cancer (odds ratio = 2.67; 99% confidence interval = 1.01-7.06). Within the subset of patients with noncardia gastric cancer, a statistically nonsignificant tendency existed for those with the intestinal versus the diffuse histologic type of noncardia gastric cancer to have a higher risk of H. pylori infection. Our results support the hypothesis of a relationship between H. pylori infection and the development of noncardia gastric adenocarcinoma.
Assuntos
Adenocarcinoma/complicações , Infecções por Helicobacter/complicações , Helicobacter pylori , Neoplasias Gástricas/complicações , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Anticorpos Antibacterianos/análise , Feminino , Infecções por Helicobacter/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Fatores de Risco , Fumar , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgiaRESUMO
BACKGROUND: Infection with Helicobacter pylori induces chronic gastritis in virtually all infected persons, and such gastritis has been associated with an increased risk of developing gastric cancer. This risk is further enhanced with cagA+ (positive for cytotoxin-associated gene A) H. pylori strains and may be a consequence of induced gastric cell proliferation and/or alteration in apoptosis (programmed cell death) in the gastric epithelium. PURPOSE: To determine whether the H. pylori cagA genotype and another virulence-related characteristic, the vacA (vacuolating cytotoxin A) s1a genotype, differentially affect epithelial cell proliferation, apoptosis, and the histologic parameters of inflammation and injury, we quantitated these characteristics in infected and uninfected persons. METHODS: Fifty patients underwent upper gastrointestinal endoscopy, and biopsy specimens were taken. Apoptotic cells in the specimens were quantitated after terminal deoxynucleotidyl transferase labeling of DNA fragments with digoxigenin-deoxyuridine triphosphate; epithelial cell proliferation was scored by immunohistochemical analysis of the proliferation-associated antigen Ki-67. Antibodies directed against H. pylori and CagA protein were measured in the serum of patients by means of enzyme-linked immunosorbent assays. Analysis of H. pylori genomic DNA, by use of the polymerase chain reaction, was performed to determine the cagA and vacA genotypes. Acute and chronic inflammation, epithelial cell degeneration, mucin depletion, intestinal metaplasia, glandular atrophy, and vacuolation were each scored in a blinded manner. Reported P values are two-sided. RESULTS: Persons harboring cagA+ strains (n = 20) had significantly higher gastric epithelial proliferation scores than persons infected with cagA-strains (n = 9) or uninfected persons (n = 21) (P = .025 and P<.001, respectively), but the difference in cell proliferation between the latter two groups was not statistically significant. The number of apoptotic cells per 100 epithelial cells (apoptotic index) in persons infected with cagA+ strains was lower than in persons infected with cagA-strains (P = .05). Apoptotic indices in the cagA+ group were similar to those in the uninfected group (P = .2). Epithelial cell proliferation was significantly correlated with acute gastric inflammation, but only in the cagA+ group (r = .44; P = .006). The cagA+ and vacA s1a genotypes were found to be concordant, confirming the close relationship between these virulence-related genotypes. CONCLUSIONS: Gastric mucosal proliferation was significantly correlated with the severity of acute gastritis in persons infected with cagA+ vacA s1a strains of H. pylori. This increased proliferation was not accompanied by a parallel increase in apoptosis. IMPLICATIONS: Increased cell proliferation in the absence of a corresponding increase in apoptosis may explain the heightened risk for gastric carcinoma that is associated with infection by cagA+ vacA s1a strains of H. pylori.
Assuntos
Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Citotoxinas/genética , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Infecções por Helicobacter/genética , Infecções por Helicobacter/patologia , Helicobacter pylori/genética , Antígenos de Bactérias , Apoptose , Divisão Celular , Sondas de DNA , Ensaio de Imunoadsorção Enzimática , Genótipo , Humanos , Inflamação/patologia , Reação em Cadeia da Polimerase , Estudos Prospectivos , RiscoRESUMO
Gastric colonization by Helicobacter pylori is a risk factor for noncardia gastric cancer. The association between H. pylori and cancer may be attributable to increased epithelial cell turnover, possibly related to antigastric antibodies. Two previous studies reported a disproportionate increase in proliferation relative to apoptosis in patients with H. pylori strains expressing the virulence-related cagA gene. This has led to the hypothesis that an abrogation of apoptosis by cagA-positive strains may promote neoplasia. We, therefore, examined the effect of H. pylori on gastric epithelial proliferation, apoptosis, and the presence of serum antiparietal cell antibodies in a large prospective study. Proliferation and apoptosis were evaluated "blindly" using validated immunohistochemical methods in two antral and two gastric corpus biopsies from 60 patients with nonulcer dyspepsia, and results were correlated with the presence of serum antiparietal cell antibodies. H. pylori colonization was assessed by histology, biopsy urease test, and serology. Proliferation was increased 2-fold in both antrum and corpus in H. pylori-positive patients, was not related to H. pylori cagA status, and was positively correlated with histological gastritis. Apoptosis was increased in the antrum and body only in patients with cagA-positive H. pylori strains. Antiparietal cell antibodies were not more prevalent in H. pylori colonization, and their presence was inversely related to epithelial apoptosis scores we therefore conclude that in patients with nonulcer dyspepsia, H. pylori carriage is associated with increased proliferation. Futhermore the cag pathogenicity island is associated with increased apoptosis. Our results do not support the hypothesis that there is a relative deficiency of gastric epithelial cell apoptosis associated with the carriage of cagA-positive strains. Host factors may be more important than bacterial products in determining the long-term outcome of H. pylori colonization.
Assuntos
Apoptose/fisiologia , Proteínas de Bactérias/genética , Mucosa Gástrica/citologia , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/patologia , Helicobacter pylori/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Bactérias/genética , Apoptose/imunologia , Autoanticorpos/sangue , Divisão Celular/imunologia , Divisão Celular/fisiologia , Dispepsia/imunologia , Dispepsia/microbiologia , Dispepsia/patologia , Células Epiteliais/citologia , Células Epiteliais/microbiologia , Feminino , Mucosa Gástrica/imunologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
To determine whether infection with a Helicobacter pylori strain possessing cagA is associated with an increased risk of development of adenocarcinoma of the stomach, we used a nested case-control study based on a cohort of 5443 Japanese-American men in Oahu, Hawaii, who had a physical examination and a phlebotomy during 1967 to 1970. We matched 103 H. pylori-infected men who developed gastric cancer during a 21-year surveillence period with 103 H. pylori-infected men who did not develop gastric cancer and tested stored serum specimens from patients and controls for the presence of serum IgG to the cagA product of H. pylori using an ELISA. The serum IgG assay using a recombinant CagA fragment had a sensitivity of 94.4% and a specificity of 92.5% when used in a clinically defined population; serological results were stable for more than 7 years. For men with antibodies to CagA, the odds ratio of developing gastric cancer was 1.9 (95% confidence interval, 0.9-4.0); for intestinal type cancer of the distal stomach, the odds ratio was 2.3 (95% confidence interval, 1.0-5.2). Age < 72 years and advanced tumor stage at diagnosis were significantly associated with CagA seropositivity. We conclude that infection with a cagA-positive H. pylori strain in comparison with a cagA-negative strain somewhat increases the risk for development of gastric cancer, especially intestinal type affecting the distal stomach.
Assuntos
Adenocarcinoma/microbiologia , Genes Bacterianos/genética , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Imunoglobulina G/sangue , Neoplasias Gástricas/microbiologia , Estudos de Casos e Controles , Genes Bacterianos/imunologia , Infecções por Helicobacter/complicações , Humanos , Masculino , Razão de ChancesRESUMO
Gastric colonization with Helicobacter pylori, especially cagA+ strains, is a risk factor for noncardia gastric adenocarcinoma, but its relationship with gastric cardia adenocarcinoma is unclear. Although incidence rates for noncardia gastric adenocarcinoma have declined steadily, paralleling a decline in H. pylori prevalence, rates for adenocarcinomas of esophagus and gastric cardia have sharply increased in industrialized countries in recent decades. To clarify the role of H. pylori infection in these tumors with divergent incidence trends, we analyzed serum IgG antibodies to H. pylori and to a recombinant fragment of CagA by antigen-specific ELISA among 129 patients newly diagnosed with esophageal/gastric cardia adenocarcinoma, 67 patients with noncardia gastric adenocarcinoma, and 224 population controls. Cancer risks were estimated by odds ratios (OR) and 95% confidence intervals (CI) using logistic regression models. Infection with cagA+ strains was not significantly related to risk for noncardia gastric cancers (OR, 1.4; CI, 0.7-2.8) but was significantly associated with a reduced risk for esophageal/cardia cancers (OR, 0.4; CI, 0.2-0.8). However, there was little association with cagA- strains of H. pylori for either cancer site (OR, 1.0 and 1.1, respectively). These findings suggest that the effects of H. pylori strains on tumor development vary by anatomical site. Further studies are needed to confirm these results and to assess whether the decreasing prevalence of H. pylori, especially cagA+ strains, may be associated with the rising incidence of esophageal/gastric cardia adenocarcinomas in industrialized countries.
Assuntos
Adenocarcinoma/etiologia , Antígenos de Bactérias , Cárdia , Neoplasias Esofágicas/etiologia , Infecções por Helicobacter/complicações , Helicobacter pylori/genética , Neoplasias Gástricas/etiologia , Adulto , Idoso , Proteínas de Bactérias/genética , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , RiscoRESUMO
BACKGROUND: Helicobacter pylori prevalence in Western countries has been declining simultaneously with increases in childhood asthma and allergic diseases; prior studies have linked these phenomena. AIMS: To examine the association between H. pylori colonisation in children and risk of asthma and related conditions at school age. We secondly examined additional effects of maternal H. pylori status by pairing with children's status. METHODS: This study was embedded in a multi-ethnic population-based cohort in Rotterdam, The Netherlands. We measured anti-H. pylori and anti-CagA antibodies in serum of children obtained at age 6 years, and of their mothers obtained during midpregnancy. Asthma or related conditions were reported for children at age 6 years. We used multivariate logistic regression analyses among 3797 subjects. RESULTS: In children, the H. pylori positivity rate was 8.7%, and 29.2% of these were CagA-positive. A child's colonisation with a CagA-negative-H. pylori strain was associated with an increased risk of asthma (Odds ratio 2.11; 95% CI 1.23-3.60), but this differed for European (3.64; 1.97-6.73) and non-European (0.52; 0.14-1.89) children. When taking into account maternal H. pylori status, only H. pylori-positive children with an H. pylori-negative mother had increased risk of asthma (2.42; 1.11-5.27), accounting for 3.4% of the asthma risk. CONCLUSIONS: Colonisation of a European child with a CagA-negative-H. pylori strain at age 6 was associated with an increased prevalence of asthma, but there was no association for non-European children. The underlying mechanisms for the observed risk differences require further research.
Assuntos
Asma/microbiologia , Infecções por Helicobacter/epidemiologia , Helicobacter pylori/isolamento & purificação , Anticorpos Antibacterianos/sangue , Criança , Feminino , Helicobacter pylori/imunologia , Humanos , Masculino , Mães , Países Baixos/epidemiologia , Prevalência , Estudos Prospectivos , RiscoRESUMO
Several risk factors have been associated with gastric cancer, among them Helicobacter pylori infection. This bacterium yields inflammation, the degree of which depends on the bacterial strain and the severity of the host response. The inflammatory response involves a complex cytokine network. Recently, polymorphisms of the genes coding for interleukin-1beta (IL-1B), interleukin-1Ra (ILRN) and interleukin-10 have been associated with an increased risk of gastric cancer. In order to determine the association of the IL-1B, IL-1RN and IL-10 polymorphisms with gastric cancer in a high-risk Costa Rican population, we analysed purified DNA of 58 gastric cancer patients, 99 controls and 41 patients classified as group I or II, according to the Japanese classification. Genotyping was carried out by PCR, PCR-RFLP and pyrosequencing analysis. We did not find any association of the IL-1B-31, IL-1B-511 and IL-10 polymorphisms with the risk for developing gastric cancer in the studied population. Carriers of the IL-1B+3954T/- had an increased risk for developing gastric cancer (OR 3.7; 95%CI: 1.34-10.2). Also we found an increased risk for developing gastric cancer for allele 2 heterozygotes of the IL-1RN (OR 2.94; 95%CI: 1.09-7.93). This is the first time that IL-1B+3954 has been associated with gastric cancer. This is one of the first studies trying to describe the role played by IL-1B, IL-1RN and IL-10 genetic polymorphisms in gastric cancer in one of the highest risk American countries. Further investigation on American countries is needed.
Assuntos
Interleucina-1/genética , Idoso , Costa Rica , Feminino , Triagem de Portadores Genéticos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
An ELISA based on a pool of United States strains of Helicobacter pylori was compared with a newly developed ELISA based on a pool of Chinese strains. Both assays were tested using sera from 132 Chinese study subjects with biopsy-proven H. pylori infection. Using cutpoints designed to yield equal specificities of 94.9% in an uninfected control population, the sensitivity of the Chinese assay was 100.0%, compared to 97.7% for the United States assay (P = 0.25 by McNemar test). These results suggest that a H. pylori assay based on pooled antigens from United States strains will perform as well in the rural Chinese population as one based on antigens from Chinese strains.
Assuntos
Ensaio de Imunoadsorção Enzimática , Gastrite/epidemiologia , Infecções por Helicobacter/epidemiologia , Helicobacter pylori , Programas de Rastreamento , População Rural/estatística & dados numéricos , Neoplasias Gástricas/epidemiologia , Adulto , China/epidemiologia , Comparação Transcultural , Estudos Transversais , Feminino , Gastrite/diagnóstico , Infecções por Helicobacter/diagnóstico , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Neoplasias Gástricas/diagnóstico , Estados Unidos/epidemiologiaRESUMO
PURPOSE: To investigate the relationship between Helicobacter pylori infection and nonsteroidal anti-inflammatory drug (NSAID) intolerance and the effect of gold use on the seroprevalence of H. pylori. PATIENTS AND METHODS: We examined the frequency of discontinuation of NSAIDs in 132 unselected patients with rheumatoid arthritis attending an outpatient subspecialty clinic, and the effect of gold compound use on the seroprevalence (by IgG enzyme-linked immunosorbent assay) of H. pylori infection in this population. Logistic and multivariate regression analysis was performed adjusting for age, gender, ethnic origin, history of ulcer, and duration of rheumatoid arthritis. RESULTS: Fifty-four patients had a positive serology for H. pylori (41%). Twenty-seven of the seropositive patients (50%), versus 45 of the seronegative patients (57.7%), had to discontinue NSAIDs (aspirin and/or nonaspirin) at least once since their diagnosis of rheumatoid arthritis because of gastrointestinal side effects (odds ratio [OR], 0.93; 95% confidence interval [CI], 0.63 to 1.38). Forty-one of the seropositive patients (76%) had received gold compounds as compared with 62 of the seronegative patients (79.5%) (OR: 0.96; 95% CI: 0.61 to 1.50). CONCLUSION: We did not find any relationship between H. pylori seropositivity and NSAID intolerance in patients with rheumatoid arthritis. In addition, our results do not demonstrate a reduction in H. pylori seroprevalence in rheumatoid arthritis patients treated with gold compounds.
Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Dispepsia/etiologia , Infecções por Helicobacter/complicações , Helicobacter pylori/isolamento & purificação , Idoso , Anti-Inflamatórios não Esteroides/uso terapêutico , Dispepsia/prevenção & controle , Feminino , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/prevenção & controle , Helicobacter pylori/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organoáuricos , Prevalência , Análise de Regressão , Estudos SoroepidemiológicosRESUMO
OBJECTIVE: To assess the serologic response to Afipia and Bartonella, previously named Rochalimaea, in patients with cat scratch disease (CSD) and a healthy control group. DESIGN: Prospective, controlled trial. SETTING: Referral clinic and hospitalized patients in a university medical center. PARTICIPANTS: Eighty patients with CSD and 57 healthy control subjects of similar age. MAIN OUTCOME MEASURES: The immune responses to Afipia felis and Bartonella henselae were evaluated by a newly developed enzyme-linked immunosorbent assay (ELISA) in patients with CSD and healthy control subjects. Responses to B henselae were also measured by indirect fluorescent antibody (IFA) tests. Antibody levels to Bartonella quintana were measured by ELISA and IFA in a limited number of patients and control subjects. RESULTS: Of the 80 patients with clinical CSD, 56 had positive results of CSD skin tests. ELISA antibody levels to A felis did not differ between patients and control subjects, but immunoglobulin M (IgM) and IgG ELISA antibodies to B henselae and B quintana were significantly higher in patients than in control subjects. IFA responses to B henselae and B quintana were also significantly higher in patients than in control subjects. CONCLUSION: Patients with CSD had significant serologic responses to B henselae and B quintana but not to A felis, suggesting that the causative agent of CSD is antigenically related to the Bartonella genus and not to Afipia. The Bartonella IgM ELISA and IFA assay were both sensitive and specific and may be used to establish the diagnosis of CSD.
Assuntos
Antígenos de Bactérias/imunologia , Infecções por Bartonella/imunologia , Bartonella henselae/imunologia , Doença da Arranhadura de Gato/imunologia , Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/imunologia , Adolescente , Adulto , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/estatística & dados numéricos , Técnica Indireta de Fluorescência para Anticorpo/métodos , Técnica Indireta de Fluorescência para Anticorpo/estatística & dados numéricos , Humanos , Lactente , Estudos Prospectivos , Testes Cutâneos/métodos , Testes Cutâneos/estatística & dados numéricos , Estatísticas não ParamétricasRESUMO
BACKGROUND: Studies in adult populations in selected countries with widely varying rates of gastric cancer have shown a weak correlation between gastric cancer mortality rates and the prevalence of CagA+ strains of H. pylori. However, only limited data are available in ethnically homogenous populations with varying rates in the same region. METHODS; We compared the prevalence of H. pylori in general and of CagA+ strains in particular among children in Shandong Province, China in areas at high (Linqu County) and low risk (Cangshan County) of gastric cancer. H. pylori status among children aged 3 to 12 years was determined by 13C-UBT, and CagA status was determined by enzyme-linked immunosorbent assay (ELISA). Because of the difficulty in obtaining blood from young children aged 3 to 4 years and from some children aged 5 years, CagA status was determined among part of children 5 years old and children 6 to 12 years old. RESULTS; Among 98 children aged 3 to 12 years in Linqu, 68 (69.4%) was H. pylori-positive, as compared with 29 (28.7%) among 101 children in Cangshan. Among children positive for 13C-UBT, the proportion of the CagA+ strains were identified was 46 (88.5%) of 52 in Linqu and 13 (81.3%) of 16 in Cangshan, respectively. CONCLUSIONS: The prevalence of H. pylori was nearly three times higher among children in Linqu than in Cangshan, which may contribute to the large differential in gastric cancer rates for two neighboring populations in Shandong Province.
Assuntos
Antígenos de Bactérias/sangue , Proteínas de Bactérias/análise , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/imunologia , Helicobacter pylori/patogenicidade , Neoplasias Gástricas/microbiologia , Anticorpos Antibacterianos/sangue , Testes Respiratórios/métodos , Isótopos de Carbono , Criança , Pré-Escolar , China/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/imunologia , Humanos , Masculino , Prevalência , Risco , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/imunologia , Ureia/análiseRESUMO
AIM: To evaluate the effectiveness of triple therapy containing either omeprazole or ranitidine bismuth citrate (RBC) to treat H. pylori infection in Vietnamese duodenal ulcer patients. METHODS: Patients infected with H. pylori were randomized to receive either omeprazole (20 mg b.d.), clarithromycin (500 mg b.d.) and amoxycillin (1 g b.d.) for 10 days (OAC), or RBC (400 mg b.d.), clarithromycin (500 mg b.d.) and amoxycillin (1 g b.d.) for 10 days (RAC). H. pylori eradication and ulcer healing was established by a follow-up oesophagogastroduodenoscopy (EGD) at least 4 weeks after therapy. Side-effects and compliance were assessed. RESULTS: One hundred and four out of 108 (96%) patients with a duodenal ulcer were infected with H. pylori. Eighty per cent of infected patients had detectable CagA IgG antibodies. Fifty-seven patients received OAC and 47 received RAC. OAC eradicated H. pylori in 91 and 86% of patients by per protocol (PP) and intention-to-treat (ITT) analysis, respectively. PP and ITT eradication rates for RAC were 96 and 91%. Ulcer healing at the follow-up EGD was 89% with OAC and 100% with RAC. Side-effects were minor. No patient failed to complete the protocol due to side-effects. CONCLUSION: Triple therapy with either omeprazole or RBC is highly effective in eradicating H. pylori and healing duodenal ulcer in Vietnamese patients.
Assuntos
Antiulcerosos/uso terapêutico , Bismuto/uso terapêutico , Úlcera Duodenal/tratamento farmacológico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Omeprazol/uso terapêutico , Ranitidina/análogos & derivados , Adolescente , Adulto , Idoso , Antiulcerosos/efeitos adversos , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Bismuto/efeitos adversos , Úlcera Duodenal/imunologia , Úlcera Duodenal/microbiologia , Feminino , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/microbiologia , Humanos , Imunoglobulina A/análise , Masculino , Pessoa de Meia-Idade , Omeprazol/efeitos adversos , Cooperação do Paciente , Ranitidina/efeitos adversos , Ranitidina/uso terapêutico , Urease/análise , VietnãRESUMO
From 183 patients undergoing upper gastrointestinal endoscopy, we used antral and corpus gastric biopsies for bacterial culture and histopathologic examination, blood samples to detect immunoglobulin G antibodies against Helicobacter pylori, and H pylori genomic DNA to analyze cytotoxin-associated gene A (cagA) and vacuolating cytotoxin (vacA) genotypes. As expected, among H pylori biopsy-positive patients, those with duodenal ulcer (DU) (n = 34) had significantly more severe chronic and acute inflammation (P <.001) and epithelial degeneration (P =.004) in the gastric antrum than in the gastric corpus. Each of those 3 parameters and H pylori density were significantly higher in the antrum of patients with DU than in patients with gastric ulcer (GU) or no ulcer. Colonization with vacA s1/cagA-positive strains of H pylori was associated with inflammation and epithelial degeneration in gastric mucosa and increased risk for peptic ulcer disease (PUD), whereas colonization with vacA s2m2/cagA-negative strains was associated with mild gastric histopathology and was not associated with any significant risk for PUD. The predominant H pylori strains in African Americans were vacA s1bm1/cagA-positive, whereas all genotypes were well represented in non-Hispanic-Caucasians. By multivariate analysis, H pylori colonization was significantly associated with DU (Adjusted odds ratio [AdjOR] = 3.2 [1.4-7.2]) and nonsteroidal anti-inflammatory drugs (NSAID) use was inversely associated (AdjOR = 0.3 [0.2-0.7]). NSAID use (AdjOR = 4.3 [1.02-18.5]) and African-American ethnicity (AdjOR = 10.9 [2.6-50]) were significantly associated with GU. Smoking and age were not significantly associated with either DU or GU. These data indicate that DU is associated with an antral-dominant gastritis, and H pylori genotype and NSAID use independently contribute to the pathogenesis of PUD. HUM PATHOL 32:264-273. This is a US Government work. There are no restrictions on its use.