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1.
BMC Med ; 22(1): 379, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39256870

RESUMEN

BACKGROUND: Helicobacter pylori colonizes the human stomach and may affect the inflammatory response, hormone production related to energy regulation, and gastrointestinal microbiota composition. Previous studies have explored a potential association between H. pylori infection and pediatric obesity with varying results. Considering the immunomodulatory effects of early-life infection with H. pylori that can confer beneficial effects, we hypothesized that we would find an inverse relationship between H. pylori seropositivity and obesity among Danish children and adolescents. METHODS: We assessed H. pylori seroprevalence in 713 subjects from an obesity clinic cohort and 990 subjects from a population-based cohort, aged 6 to 19 years, and examined its association with obesity and other cardiometabolic risk factors. RESULTS: No association was found between H. pylori and body mass index standard deviation score (BMI SDS). H. pylori seropositivity was, however, significantly associated with higher fasting plasma glucose levels and the prevalence of hyperglycemia. CONCLUSION: While we did not find an association between H. pylori seropositivity and BMI SDS, we observed a significant association with higher fasting plasma glucose levels and increased prevalence of hyperglycemia, suggesting that H. pylori infection may contribute to impaired glucose regulation in Danish children and adolescents.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Hiperglucemia , Humanos , Adolescente , Niño , Dinamarca/epidemiología , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/sangre , Masculino , Femenino , Hiperglucemia/epidemiología , Hiperglucemia/sangre , Estudios Seroepidemiológicos , Adulto Joven , Obesidad Infantil/epidemiología , Obesidad Infantil/sangre , Obesidad Infantil/microbiología , Estudios de Cohortes , Índice de Masa Corporal , Prevalencia , Glucemia/análisis
2.
Int J Mol Sci ; 19(5)2018 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-29751550

RESUMEN

Helicobacter pylori is the most abundant bacterium in the gastric epithelium, and its presence has been associated with the risk of developing gastric cancer. As of 15 years ago, no other bacteria were associated with gastric epithelial colonization; but thanks to new methodologies, many other non-H. pylori bacteria have been identified. It is possible that non-H. pylori may have a significant role in the development of gastric cancer. Here, we discuss the specific role of H. pylori as a potential trigger for events that may be conducive to gastric cancer, and consider whether or not the rest of the gastric microbiota represent an additional risk in the development of this disease.


Asunto(s)
Mucosa Gástrica/microbiología , Mucosa Gástrica/patología , Infecciones por Helicobacter/metabolismo , Infecciones por Helicobacter/microbiología , Helicobacter pylori/patogenicidad , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/microbiología , Animales , Humanos
3.
Int J Syst Evol Microbiol ; 67(5): 1247-1254, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28100298

RESUMEN

To better characterize murine intestinal microbiota, a large number (187) of Gram-positive-staining, rod- and coccoid-shaped, and facultatively or strictly anaerobic bacteria were isolated from small and large intestinal contents from mice. Based on 16S rRNA gene sequencing, a total 115 isolates formed three phylogenetically distinct clusters located within the family Erysipelotrichaceae. Group 1, as represented by strain NYU-BL-A3T, was most closely related to Allobaculum stercoricanis, with 16S rRNA gene sequence similarity values of 87.7 %. A second group, represented by NYU-BL-A4T, was most closely related to Faecalibaculum rodentium, with 86.6 % 16S rRNA gene sequence similarity. A third group had a nearly identical 16S rRNA gene sequence (99.9 %) compared with the recently described Faecalibaculum rodentium, also recovered from a laboratory mouse; however, this strain had a few differences in biochemical characteristics, which are detailed in an emended description. The predominant (>10 %) cellular fatty acids of strain NYU-BL-A3T were C16 : 0 and C18 : 0, and those of strain NYU-BL-A4T were C10 : 0, C16 : 0, C18 : 0 and C18 : 1ω9c. The two groups could also be distinguished by multiple biochemical reactions, with the group represented by NYU-BL-A4T being considerably more active. Based on phylogenetic, biochemical and chemotaxonomic criteria, two novel genera are proposed, Ileibacterium valens gen. nov., sp. nov. with NYU-BL-A3T (=ATCC TSD-63T=DSM 103668T) as the type strain and Dubosiella newyorkensis gen. nov., sp. nov. with NYU-BL-A4T (=ATCC TSD-64T=DSM 103457T) as the type strain.


Asunto(s)
Faecalibacterium/clasificación , Intestinos/microbiología , Ratones/microbiología , Filogenia , Tenericutes/clasificación , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Tenericutes/genética , Tenericutes/aislamiento & purificación
4.
Helicobacter ; 22(2)2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27786400

RESUMEN

BACKGROUND: Preeclampsia (PE), small for gestational age (SGA), and spontaneous preterm birth (PTB) each may be complications of impaired placental function in pregnancy. Although their exact pathogenesis is still unknown, certain infectious agents seem to play a role. Helicobacter pylori (H. pylori) colonization has been associated with increased risk for PE. Our aim was to assess the association between H. pylori colonization and PE, SGA, and PTB. MATERIAL AND METHODS: We measured IgG anti-H. pylori and CagA antibodies in serum of pregnant women (median 20.5 weeks, range 16.5-29.4) who participated in a population-based prospective cohort study. Delivery and medical records were assessed. Information on demographics, education, and maternal risk factors was collected by questionnaire. We used multivariate logistic regression analyses to assess associations between H. pylori colonization and PE, SGA, and PTB. RESULTS: In total, 6348 pregnant women were assessed. H. pylori positivity was found in 2915 (46%) women, of whom 1023 (35%) also were CagA-positive. Pregnancy was complicated by PE, SGA, or PTB in 927 (15%) women. H. pylori colonization was associated with PE (aOR 1.51; 95%CI 1.03-2.25). Differentiation according to CagA status revealed the same risk. H. pylori was positively related with SGA, mainly explained by CagA-positive strains (aOR 1.34; 1.04-1.71). No association was observed between H. pylori and PTB. CONCLUSIONS: Our data suggest that H. pylori colonization may be a risk factor for PE and SGA. If these associations are confirmed by future studies and shown to be causal, H. pylori eradication may reduce related perinatal morbidity and mortality.


Asunto(s)
Infecciones por Helicobacter/complicaciones , Recién Nacido Pequeño para la Edad Gestacional , Preeclampsia/epidemiología , Nacimiento Prematuro/epidemiología , Adulto , Anticuerpos Antibacterianos/sangre , Femenino , Helicobacter pylori/inmunología , Humanos , Embarazo , Estudios Prospectivos , Factores de Riesgo , Encuestas y Cuestionarios , Adulto Joven
5.
BMC Microbiol ; 16(1): 201, 2016 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-27590005

RESUMEN

BACKGROUND: Highly virulent strains of the gastric pathogen Helicobacter pylori encode a type IV secretion system (T4SS) that delivers the effector protein CagA into gastric epithelial cells. Translocated CagA undergoes tyrosine phosphorylation by members of the oncogenic c-Src and c-Abl host kinases at EPIYA-sequence motifs A, B and D in East Asian-type strains. These phosphorylated EPIYA-motifs serve as recognition sites for various SH2-domains containing human proteins, mediating interactions of CagA with host signaling factors to manipulate signal transduction pathways. Recognition of phospho-CagA is mainly based on the use of commercial pan-phosphotyrosine antibodies that were originally designed to detect phosphotyrosines in mammalian proteins. Specific anti-phospho-EPIYA antibodies for each of the three sites in CagA are not forthcoming. RESULTS: This study was designed to systematically analyze the detection preferences of each phosphorylated East Asian CagA EPIYA-motif by pan-phosphotyrosine antibodies and to determine a minimal recognition sequence. We synthesized phospho- and non-phosphopeptides derived from each predominant EPIYA-site, and determined the recognition patterns by seven different pan-phosphotyrosine antibodies using Western blotting, and also investigated representative East Asian H. pylori isolates during infection. The results indicate that a total of only 9-11 amino acids containing the phosphorylated East Asian EPIYA-types are required and sufficient to detect the phosphopeptides with high specificity. However, the sequence recognition by the different antibodies was found to bear high variability. From the seven antibodies used, only four recognized all three phosphorylated EPIYA-motifs A, B and D similarly well. Two of the phosphotyrosine antibodies preferentially bound primarily to the phosphorylated motif A and D, while the seventh antibody failed to react with any of the phosphorylated EPIYA-motifs. Control experiments confirmed that none of the antibodies reacted with non-phospho-CagA peptides and in accordance were able to recognize phosphotyrosine proteins in human cells. CONCLUSIONS: The results of this study disclose the various binding preferences of commercial anti-phosphotyrosine antibodies for phospho-EPIYA-motifs, and are valuable in the application for further characterization of CagA phosphorylation events during infection with H. pylori and risk prediction for gastric disease development.


Asunto(s)
Antígenos Bacterianos/inmunología , Proteínas Bacterianas/inmunología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/inmunología , Fosfotirosina/inmunología , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Anticuerpos/química , Anticuerpos/inmunología , Antígenos Bacterianos/química , Antígenos Bacterianos/genética , Antígenos Bacterianos/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Línea Celular , Mucosa Gástrica/metabolismo , Infecciones por Helicobacter/inmunología , Infecciones por Helicobacter/metabolismo , Helicobacter pylori/genética , Helicobacter pylori/metabolismo , Humanos , Datos de Secuencia Molecular , Fosforilación , Fosfotirosina/aislamiento & purificación , Fosfotirosina/metabolismo , Procesamiento Proteico-Postraduccional , Proteínas Tirosina Quinasas/metabolismo , Alineación de Secuencia , Transducción de Señal , Estómago/microbiología , Estómago/patología , Neoplasias Gástricas/microbiología , Sistemas de Secreción Tipo IV
6.
J Infect Dis ; 211(12): 1895-904, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25583170

RESUMEN

BACKGROUND: Previous studies have demonstrated an association between antibiotic use and the development of skin abscesses. We tested the hypothesis that alterations in the composition of the cutaneous microbiota may predispose individuals to skin abscesses. METHODS: We studied 25 patients with skin abscesses and 25 age-matched controls, who each completed a questionnaire. Skin swab samples were obtained for DNA analysis from 4 sites around the abscess site (hereafter, "peri-abscess specimens") and from similar sites on the patient's contralateral side and on healthy control subjects. DNA was extracted and analyzed by quantitative polymerase chain reaction (qPCR) and high-throughput sequencing. The purulent abscess drainage was sent for culture. RESULTS: Fifteen patients with abscess were infected with Staphylococcus aureus. Use of nuc qPCR to quantitate S. aureus revealed a significantly greater frequency of positive results for peri-abscess and contralateral skin samples, compared with control skin specimens. Analysis of community structure showed greater heterogeneity in the control samples than in the peri-abscess and contralateral samples. Metagenomic analysis detected significantly more predicted genes related to metabolic activity in the peri-abscess specimens than in the control samples. CONCLUSIONS: The peri-abscess microbiome was similar to the contralateral microbiome, but both microbiomes differed from that for control patients. Host characteristics affecting microbial populations might be important determinants of abscess risk.


Asunto(s)
Absceso/diagnóstico , Microbiota , Pacientes Ambulatorios , Enfermedades Cutáneas Bacterianas/diagnóstico , Piel/microbiología , Adolescente , Adulto , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Reacción en Cadena en Tiempo Real de la Polimerasa , Encuestas y Cuestionarios , Adulto Joven
7.
Gut ; 64(8): 1200-8, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25192563

RESUMEN

OBJECTIVE: Helicobacter pylori colonisation rates in childhood have declined in Western populations, but it is unknown whether this trend is similar in children of non-Western ethnic backgrounds, born in a Western country. We aimed to identify H. pylori status in children, and determine mother-to-child transmission and risk factors for colonisation. DESIGN: Antibodies against H. pylori and cytotoxin-associated gene A (CagA) were measured in children participating in a population-based prospective cohort study in Rotterdam, the Netherlands. Information on demographics and characteristics was collected using questionnaires. RESULTS: We analysed the serum of 4467 children (mean age 6.2 years±0.4 SD) and compared the results with the H. pylori status of their mothers (available for 3185 children). Overall, 438 (10%) children were H. pylori-positive, of whom 142 (32%) were CagA-positive. Independent risk factors for colonisation were: maternal H. pylori positivity (OR 2.12; 95% CI 1.62 to 2.77), non-Dutch ethnicity (OR 2.05; 95% CI 1.54 to 2.73), female gender (OR 1.47; 95% CI 1.20 to 1.80) and lower maternal education level (OR 1.38; 95% CI 1.06 to 1.79). Comparing mothers and children, we found an intergenerational decrease of 76% and 77% for Hp(+)CagA(-) and Hp(+)CagA(+)-strains, respectively, consistent across all nine ethnic groups studied. Male gender, higher maternal educational level and no older siblings, were independently associated with absence of H. pylori. CONCLUSIONS: Although the highest H. pylori and CagA prevalence was found in children of non-Dutch ethnicities, the decreased colonisation rates were uniform across all ethnic groups, implying the importance of environmental factors in H. pylori transmission in modern cities, independent of ethnicity.


Asunto(s)
Etnicidad/etnología , Infecciones por Helicobacter/etnología , Población Urbana , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Países Bajos/epidemiología , Prevalencia , Estudios Prospectivos
8.
BMC Cancer ; 14: 296, 2014 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-24774100

RESUMEN

BACKGROUND: Gastric Helicobacter pylori (H. pylori) infection and colorectal polyps are more prevalent in African Americans than in the general population. We aimed to investigate whether gastric H. pylori infection is associated with colorectal polyps in African Americans. METHODS: Medical records of African Americans, 40 years and older (n = 1256) who underwent bidirectional gastrointestinal endoscopy on the same day were reviewed. H. pylori status was assessed by immunohistochemistry on gastric specimens. Colorectal polyps were confirmed by histological examination of colorectal biopsies. A subset of serum samples from healthy and polyp-bearing patients (n = 163) were analyzed by ELISA for anti-H. pylori and anti-CagA antibodies. The crude and adjusted effect of H. pylori on the risk of colorectal adenoma and polyp were computed by logistic regression models. RESULTS: The prevalence of colorectal polyps and adenomas were 456 (36%) and 300 (24%) respectively. Colorectal polyps were more prevalent in gastric H. pylori infected than non-infected subjects [43% vs. 34%; Odds Ratio (OR) (95% CI): 1.5 (1.2-1.9), P = 0.001]. Patients with H. pylori-associated chronic active gastritis were at high risk to have adenomas [Unadjusted OR (95% CI): 1.3 (1.0-1.8); P = 0.04]. There was no difference in histopathology, size, or location of polyps with respect to H. pylori status. Gastric H. pylori infection, age, male gender and high risk clinical presentations were independent risk factors for colorectal polyps. Serological testing also revealed a higher prevalence of H. pylori and its toxin Cag-A in polyp patients vs. non polyp patients' sera, although in a non-statistically significant manner. CONCLUSIONS: This study showed that current gastric H. pylori infection is associated with an increased risk of colorectal polyps in African Americans. Patients with H. pylori induced gastritis may benefit from early screening colonoscopy as a preventative measure for colorectal cancer.


Asunto(s)
Pólipos del Colon/patología , Neoplasias Colorrectales/patología , Infecciones por Helicobacter/patología , Helicobacter pylori/patogenicidad , Negro o Afroamericano , Anciano , Anciano de 80 o más Años , Biopsia , Pólipos del Colon/microbiología , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/microbiología , Endoscopía Gastrointestinal , Femenino , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/microbiología , Helicobacter pylori/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
9.
J Infect Dis ; 207(7): 1105-14, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23300163

RESUMEN

BACKGROUND: Diabetic foot infections are a leading cause of lower extremity amputations. Our study examines the microbiota of diabetic skin prior to ulcer development or infection. METHODS: In a case-control study, outpatient males were recruited at a veterans hospital. Subjects were swabbed at 4 cutaneous sites, 1 on the forearm and 3 on the foot. Quantitative polymerase chain reaction (qPCR) with primers and probes specific for bacteria, Staphylococcus species, Staphylococcus aureus, and fungi were performed on all samples. High-throughput 16S ribosomal RNA (rRNA) sequencing was performed on samples from the forearm and the plantar aspect of the foot. RESULTS: qPCR analysis of swab specimens from 30 diabetic subjects and 30 control subjects showed no differences in total numbers of bacteria or fungi at any sampled site. Increased log concentrations of Staphylococcus aureus, quantified by the number of nuc gene copies, were present in diabetic men on the plantar aspect of the foot. High-throughput 16S rRNA sequencing found that, on the foot, the microbiota in controls (n = 24) was dominated by Staphylococcus species, whereas the microbiota in diabetics (n = 23) was more diverse at the genus level. The forearm microbiota had similar diversity in diabetic and control groups. CONCLUSIONS: The feet of diabetic men had decreased populations of Staphylococcus species, increased populations of S. aureus, and increased bacterial diversity, compared with the feet of controls. These ecologic changes may affect the risk for wound infections.


Asunto(s)
Diabetes Mellitus/patología , Pie Diabético/microbiología , Metagenoma , Piel/microbiología , Staphylococcus aureus/aislamiento & purificación , Adulto , Anciano , Arthrodermataceae/genética , Arthrodermataceae/aislamiento & purificación , Arthrodermataceae/patogenicidad , Carga Bacteriana , Proteínas Bacterianas/genética , Estudios de Casos y Controles , Pie Diabético/patología , Antebrazo/microbiología , Genes Bacterianos , Genes de ARNr , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Nucleasa Microcócica/genética , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Piel/patología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/patología , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidad , Adulto Joven
12.
Med Mycol ; 51(8): 884-7, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23815437

RESUMEN

A total of 135 stomach samples from patients with gastrointestinal diseases and normal controls were examined for Helicobacter pylori infection and Candida colonization. Candida krusei was found in specimens from 20% bleeding, 52% ulcer, and 100% gastritis patients, whereas H. pylori infection rates were 82%, 35% and 30%, respectively, for the same groups of patients. C. krusei was not detected in stomach samples from normal controls.


Asunto(s)
Candida/aislamiento & purificación , Candidiasis/epidemiología , Candidiasis/microbiología , Gastritis/complicaciones , Hemorragia Gastrointestinal/complicaciones , Úlcera Gástrica/complicaciones , Adolescente , Adulto , Anciano , Candida/clasificación , Helicobacter pylori/aislamiento & purificación , Humanos , Persona de Mediana Edad , Prevalencia , Estómago/microbiología , Adulto Joven
13.
J Gastroenterol Hepatol ; 28(11): 1705-11, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23808840

RESUMEN

BACKGROUND AND AIM: At the same time that Helicobacter pylori prevalence is declining in Western countries, immigrants from developing countries with high H. pylori prevalence have settled in Western urban areas. Actual epidemiological data on H. pylori in a migrant community may help in realizing a more selective approach to assess H. pylori-related diseases. We aimed to define H. pylori prevalence as well as risk groups for H. pylori in a cohort of young women living in a multi-ethnic European city. METHODS: We measured Immunoglobulin G (IgG) anti-H. pylori and CagA-antibodies in serum of pregnant women included in a population-based prospective cohort study, the Generation R study. Information on demographics and socioeconomic status was collected by questionnaires. Chi-square and logistic regression were used. RESULTS: In total, 3146 (46%) of the 6837 tested women (mean age 29.7 ± 5.3) were H. pylori-positive and 1110 (35%) of them were CagA-positive. The H. pylori prevalence in Dutch women was 24%, which was significantly lower than in non-Dutch women (64%; P < 0.001). In particular, H. pylori positivity was found in 92% of Moroccan (odds ratio 19.2; 95% confidence interval 11.8-32.0), 80% of Cape Verdean (7.6; 5.0-11.5), 81% of Turkish (9.0; 6.7-12.1), 60% of Dutch Antillean (3.3; 2.3-4.7), and 58% of Surinamese women (3.0; 2.3-3.8). Among H. pylori-positive Dutch subjects, 19% were CagA-positive compared with 40% of the non-Dutch subjects (P < 0.001). CONCLUSIONS: Despite a general trend of declining prevalence in Western countries, H. pylori remains highly prevalent in migrant communities, which may constitute target groups for screening and eradication to prevent H. pylori-related diseases.


Asunto(s)
Emigrantes e Inmigrantes/estadística & datos numéricos , Infecciones por Helicobacter/etnología , Infecciones por Helicobacter/epidemiología , Helicobacter pylori , Adulto , Factores de Edad , Cabo Verde/etnología , Distribución de Chi-Cuadrado , Estudios de Cohortes , Demografía , Europa (Continente)/epidemiología , Femenino , Infecciones por Helicobacter/prevención & control , Humanos , Modelos Logísticos , Marruecos/etnología , Países Bajos/etnología , Embarazo , Prevalencia , Riesgo , Clase Social , Encuestas y Cuestionarios , Turquía/etnología , Adulto Joven
14.
Int J Cancer ; 131(10): 2294-9, 2012 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-22377818

RESUMEN

Our aim was to examine the humoral immune response against Streptococcus gallolyticus subspecies gallolyticus antigens in individuals subjected to a routine colonoscopy in which colon adenomatous polyps were present or not. Serum samples from 133 individuals with adenomatous polyps and serum samples from 53 individuals with a normal colonoscopy were included. Western blot was performed in all subjects using a whole cell antigen from S. gallolyticus ATCC 9809, and rabbit antisera against the whole cell bacteria was prepared as a control. By analyzing the immune profile of the rabbit-immunized sera by Western-blot, at least 22 proteins were identified as immunogenic in S. gallolyticus. When we evaluated sera from human subjects, two proteins of approximately 30 and 22 kDa were most prominent. Based on this 2-protein band pattern, Western-blot profiles from human subjects were compared. The detection of a protein band of 22 kDa was associated with the presence of adenomatous polyps in colon [odds ratios (OR) 7.98, 95% confidence intervals (CI): 3.54-17.93], p < 0.001. When the presence of the 30 kDa protein alone or both the 22 and 30 kDa proteins were analyzed, the OR increased to 22.37 (95% CI: 3.77-131.64), p < 0.001. The specificity was 84.9 for the presence of the 22 kDa protein, and 98.1 for the presence of the 30 kDa protein alone or both 22 and 30 kDa bands. Serum from individuals with adenomatous polyps recognized two proteins from S. gallolyticus. This result confirmed the possible association of S. gallolyticus with adenomatous polyps in the colon.


Asunto(s)
Pólipos Adenomatosos/inmunología , Pólipos del Colon/inmunología , Streptococcus/inmunología , Pólipos Adenomatosos/diagnóstico , Pólipos Adenomatosos/microbiología , Adulto , Anciano , Anciano de 80 o más Años , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Antígenos Bacterianos/inmunología , Biomarcadores/sangre , Pólipos del Colon/diagnóstico , Pólipos del Colon/microbiología , Humanos , Persona de Mediana Edad , Conejos , Sensibilidad y Especificidad , Pruebas Serológicas
16.
Helicobacter ; 17(3): 232-7, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22515362

RESUMEN

BACKGROUND: The prevalence of Helicobacter pylori in Western populations has steadily decreased. This has been suggested as one of the factors involved in the recent increase of asthma and allergy. Some studies have reported a negative association between H. pylori and asthma and allergy, but data are inconsistent and there are a few studies in children. AIM: We investigated whether the prevalence of H. pylori was associated with asthma symptoms, allergic rhinitis, and atopic dermatitis in childhood. METHODS: We determined IgG anti-H. pylori and CagA antibodies in serum of Dutch children, who took part in the PIAMA birth cohort study. Serum was collected from 545 children, aged 7-9 years (Dutch ethnicity 91.5%). Symptoms of asthma and atopy were assessed by yearly questionnaires. Chi-square tests and logistic regression were used. RESULTS: We found 9%H. pylori and 0.9% CagA seropositivity. Twelve (5.9%) children with reported wheezing ever were H. pylori positive, compared to 37 (10.9%) of the non-wheezers (p = .05). No significant differences in H. pylori prevalence were found between children with or without allergic rhinitis (8.5% vs 9.5%), atopic dermatitis (8.7% vs 9.2%), and physician-diagnosed asthma (7.1% vs 9.4%). Multivariate analysis showed no significant associations between H. pylori seropositivity and wheezing (OR 0.52; 95% CI 0.25-1.06), allergic rhinitis (OR 0.96; 95% CI 0.51-1.81), atopic dermatitis (OR 1.05; 95% CI 0.56-1.98) or physician-diagnosed asthma (OR 0.87; 95% CI 0.37-2.08). CONCLUSION: We found a borderline significantly lower H. pylori seropositivity in children with wheezing compared to non-wheezers, but no association between H. pylori serum-antibody status and allergic rhinitis, atopic dermatitis, or asthma.


Asunto(s)
Asma/microbiología , Dermatitis Atópica/microbiología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/inmunología , Rinitis Alérgica Perenne/microbiología , Anticuerpos Antibacterianos/inmunología , Asma/complicaciones , Asma/inmunología , Niño , Dermatitis Atópica/complicaciones , Dermatitis Atópica/inmunología , Femenino , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/inmunología , Helicobacter pylori/aislamiento & purificación , Humanos , Masculino , Rinitis Alérgica Perenne/complicaciones , Rinitis Alérgica Perenne/inmunología
17.
J Trop Pediatr ; 58(3): 231-4, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21752863

RESUMEN

The aims of this study were to assess the prevalence of Helicobacter pylori infection and to introduce a new algorithm to improve its diagnosis in Cuban symptomatic children. One hundred and thirty-three consecutive children with upper gastrointestinal symptoms were studied. Patients were endoscoped and antral biopsies were obtained for rapid urease test (RUT), culture and histology. Prevalence of H. pylori infection was 30.8%. No statistical differences were found concerning demographic, socio-economic factors or chief clinical complaints, between H. pylori-positive and negative children, except for haematemesis, which was significantly higher in infected children (p = 0.003). Histologically, there was statistical association between moderate chronic gastritis in infected children (p = 0.04). Culture and RUT had the highest specificity and sensitivity, respectively. The prevalence of H. pylori infection in Cuban symptomatic children is similar to the one observed in developed countries. Culture and RUT is a useful combination to diagnose H. pylori infection in paediatric patients.


Asunto(s)
Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/epidemiología , Helicobacter pylori/aislamiento & purificación , Dolor Abdominal/etiología , Adolescente , Algoritmos , Biopsia , Niño , Preescolar , Cuba/epidemiología , Endoscopía Gastrointestinal/métodos , Femenino , Infecciones por Helicobacter/microbiología , Hospitales de Enseñanza , Humanos , Masculino , Prevalencia , Factores de Riesgo , Factores Socioeconómicos
18.
Helicobacter ; 16(6): 475-81, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22059399

RESUMEN

BACKGROUND: Helicobacter pylori are a persistent colonizer of the human gastric mucosa, which can lead to the development of peptic ulcer disease and gastric adenocarcinomas. However, H. pylori can asymptomatically colonize a host for years. One factor that has been hypothesized to contribute to such persistence is the production of Lewis (Le) antigens in the lipopolysaccharide layer of the bacterial outer membrane as a form of molecular mimicry, because humans also express these antigens on their gastric mucosa. Humans and H. pylori both are polymorphic for Le expression, which is driven in H. pylori by variation at the Le synthesis loci. In this report, we sought to characterize Le genotypic and phenotypic variation in geographically diverse H. pylori isolates. MATERIALS AND METHODS: From patients undergoing endoscopy in 29 countries, we determined Le phenotypes of 78 H. pylori strains and performed genotyping of the galT and ß-(1,3)galT loci in 113 H. pylori strains. RESULTS: Le antigen phenotyping revealed a significant (p < .0001) association between type 1 (Le(a) and Le(b) ) expression and strains of East Asian origin. Genotyping revealed a significant correlation between strain origin and the size of the promoter region upstream of the Le synthesis gene, galT (p < .0001). CONCLUSION: These results indicate that the heterogeneity of human Le phenotypes is reflected in their H. pylori colonizing strains and suggest new loci that can be studied to assess the variation of Le expression.


Asunto(s)
Antígenos Bacterianos/biosíntesis , Antígenos Bacterianos/genética , Variación Genética , Helicobacter pylori/genética , Helicobacter pylori/aislamiento & purificación , Antígenos del Grupo Sanguíneo de Lewis/biosíntesis , Antígenos del Grupo Sanguíneo de Lewis/genética , Perfilación de la Expresión Génica , Genotipo , Humanos , Filogeografía
19.
Helicobacter ; 16(5): 405-9, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21923687

RESUMEN

BACKGROUND: The prevalence of Helicobacter pylori has declined over recent decades in developed countries. The increasing prevalence with age is largely because of a birth cohort effect. We previously observed a decline in H. pylori prevalence in 6- to 8-year-old Dutch children from 19% in 1978 to 9% in 1993. Knowledge about birth-cohort-related H. pylori prevalence is relevant as a predictor for the future incidence of H. pylori-associated conditions. AIM: The aim of this study was to investigate whether the birth cohort effect of H. pylori observed between 1978 and 1993 continued in subsequent years. METHODS: Anti-H. pylori IgG antibodies and anti-CagA IgG antibodies were determined in serum samples obtained in 2005/2006 from 545 Dutch children aged 7-9 years who participated in the Prevention and Incidence of Asthma and Mite Allergy birth cohort. The H. pylori and CagA antibodies were determined by enzyme-linked immunosorbent assays that have been extensively validated in children, with a 94% sensitivity for H. pylori colonization and a 92.5% sensitivity for colonization with a cagA-positive strain. RESULTS: Of the 545 children (M/F 300/245), most (91.5%) were of Dutch descent. The H. pylori positivity rate was 9% (95% CI 6.6-11.4%). The prevalence of CagA antibodies was 0.9% (95% CI 0.1-1.6%). No significant differences were demonstrated in H. pylori and cagA prevalence in relation to gender or ethnicity. CONCLUSION: The prevalence of H. pylori in childhood has remained stable in the Netherlands from 1993 to 2005, suggesting a stabilization of the previously decreasing trend in subsequent birth cohorts. This finding may reflect stabilization in determinants such as family size, housing, and hygienic conditions (or offset by day care). If confirmed in other populations in developed countries, it implies that colonization with H. pylori will remain common in the coming decades. Remarkably however, the rate of colonization with cagA(+) H. pylori strains has become very low, consistent with prior observations that cagA(+) strains are disappearing in Western countries.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/inmunología , Proteínas Bacterianas/inmunología , Infecciones por Helicobacter/epidemiología , Helicobacter pylori/aislamiento & purificación , Niño , Estudios de Cohortes , Humanos , Países Bajos/epidemiología , Prevalencia
20.
BMC Gastroenterol ; 11: 37, 2011 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-21489301

RESUMEN

BACKGROUND: Appetite and energy expenditure are regulated in part by ghrelin and leptin produced in the gastric mucosa, which may be modified by H. pylori colonization. We prospectively evaluated the effect of H. pylori eradication on meal-associated changes in serum ghrelin and leptin levels, and body weight. METHODS: Veterans referred for upper GI endoscopy were evaluated at baseline and ≥8 weeks after endoscopy, and H. pylori status and body weight were ascertained. During the first visit in all subjects, and during subsequent visits in the initially H. pylori-positive subjects and controls, blood was collected after an overnight fast and 1 h after a standard high protein meal, and levels of eight hormones determined. RESULTS: Of 92 enrolled subjects, 38 were H. pylori-negative, 44 H. pylori-positive, and 10 were indeterminate. Among 23 H. pylori-positive subjects who completed evaluation after treatment, 21 were eradicated, and 2 failed eradication. After a median of seven months following eradication, six hormones related to energy homeostasis showed no significant differences, but post-prandial acylated ghrelin levels were nearly six-fold higher than pre-eradication (p=0.005), and median integrated leptin levels also increased (20%) significantly (p<0.001). BMI significantly increased (5 ± 2%; p=0.008) over 18 months in the initially H. pylori-positive individuals, but was not significantly changed in those who were H. pylori-negative or indeterminant at baseline. CONCLUSIONS: Circulating meal-associated leptin and ghrelin levels and BMI changed significantly after H. pylori eradication, providing direct evidence that H. pylori colonization is involved in ghrelin and leptin regulation, with consequent effects on body morphometry.


Asunto(s)
Alimentos , Ghrelina/sangre , Infecciones por Helicobacter/sangre , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/efectos de los fármacos , Leptina/sangre , Anciano , Amoxicilina/uso terapéutico , Antibacterianos/uso terapéutico , Índice de Masa Corporal , Claritromicina/uso terapéutico , Quimioterapia Combinada , Femenino , Infecciones por Helicobacter/microbiología , Humanos , Masculino , Persona de Mediana Edad , Inhibidores de la Bomba de Protones/uso terapéutico
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