Background: There is nearly 3,5 billion people infected Helicobacter pylori in over the world. Objectives: To investigate Helicobacter pylori (HP) seroprevalence (by ELISA technique) and related risk factors (by questionnaire set) in children of different ethnics. Subjects and method: This cross - sectional study was carried out in Ban Qua, a mountainous village of a northern border province with a population of 408 children under 18 from 245 households (consisting of 781 members) with 5 ethnics. HP seroprevalence was determined by ELISA technique and risk factors by structure questionnaire. Results: HP seroprevalence in children under 18 was 26.7% without sex predominance but with significant ethnical difference: 16.1 % in H\u2019mong, 16.7% in Tay, 20.3% in Dao, 38.5% in Giay and 41.0% in Kinh (p < 0.001); and increased with age, particularly in 3 - 6 aged group, by the rate of 1-1.5%/year. The study results showed that age, HP infection in sibling, breastfeeding beyond 12 months and family history of gastro duodenal disorders were independently associated to HP infection in children. In addition, HP infection in parents and illiteracy in mothers were also significantly related to higher seropositivity in children (p<0.03 and <0.045, respectively). Conclusion: This study showed that although the rate of HP infection in minority ethnics was lower than in the majority (Kinh), but risk factors for the infection were somewhat similar to those identified in other studies in Kinh people.
Helicobacter pylori/ pathogenicity ; Child

Background: Helicobacter pylori infection is difficult to diagnose in children, especially in developing countries where non - invasive methods such as urea - breath test are often not available. Objectives: To evaluate the sensitivity and specificity of a new monoclonal antibody - based antigen - in - stool enzyme immunoassay (Premier Platinum HpSA PLUS) for diagnosis of H. pylori infection in Vietnamese children. Subjects and method: Sensitivity of the antigen - in - stool test was evaluated in 232 children, 3 - 15 years of age, who were positive for H. pylori infection by culture from biopsies. For evaluation of the specificity 241 children of similar age with non - gastrointestinal conditions were included with blood and stool samples. Results:Among the culture - positive children, 224 were also positive by Premier Platinum HpSA PLUS. Among the control children 98 had negative for H. pylori infection as established by serology, using two ELiSAs (in house and Pyloriset EIA - Gill) and an immunblot (Helicoblot 2.1). These 93 childrenhad H. pylori negative also in the stool test. The sensitivity, specificity, and positive and negative predictive values of Premier Platinum HpSA PLUS were thus found to be 96.6%, 94.9%, 97.8%, and 92.1 %, respectively. Conclusion: The outcome have demonstrated Premium Platinum HpSA PLUS to be a reliable method for detection of H. pylori infection in Vietnamese children.
Helicobacter pylori/ pathogenicity ; Child

Background: Helicobacter pylori (HP), the main reason caused digestive disease in many people. Objectives: To explore the relationship between seroprevalence of HP in children and the duration of breastfeeding (BF) in childhood. Subjects and method:Data on BF duration were collected, using a structured questionnaires, then analyzed by logistic regression, in three different groups: (1) 764 children aged from 6 months to 15 years admitted to or visiting a tertiary teaching hospital, (2) 369 children under 18 from a rural village in the centre and (3) 408 children under 18 from a multi - ethnic village in the mountainous area of the northern part of Vietnam. HP infection was determined by ELISA technique. Results: HP seroprevalence was of 26.0% (69/265) in children breastfed longer than 6 months, significant lower than 37.4% (308/556) in children breastfed shorter than 6 months in the first group [p<0.02, OR (95% CI): 0.63 (0.41 - 0.84)]. This rate was of 39.7% (27/68) in children breastfed longer than 24 months, significant lower than 59.1 % (178/301) in children breastfed shorter than 24 months in the second group [p=0.01, OR (95% CI): 0.46 (0.27 - 0.78)]. However, in the 3rd group of different minority ethnics from mountainous area, where living and hygiene levels were low, HP seroprevalence was of 29.7% (82/276), significant higher than 20.5% (27/132) in children breastfed shorter than 12 months [p = 0.03, OR (95% CI): 1.64 (1.00 - 2.70)]. Conclusion: Long duration of breastfeeding seemed protective against HP acquisition in Kinh children but might become a risk factor for HP infection in mountainous children.
Helicobacter pylori/ pathogenicity ; Child

Helicobacter pylori (H. pylori) causes chronic gastritis in human stomach, a minority of which progress to peptic ulcer disease, atrophic gastritis, or gastric malignancies. Clinical outcomes of H. pylori infection has been shown to depend on the variability of H. pylori virulence factors, host susceptibility, environmental factors and their interactions. This review provides an update on the molecular pathogenesis of H. pylori infection, focused on H. pylori virulence factors, H. pylori-gastric epithelium interactions, and modulation of host cell signaling. Understanding of H. pylori molecular pathogenic mechanism will facilitate the development of novel treatment strategies for eradication of the bacterium and prevention of H. pylori-induced gastropathy.
Helicobacter Infections/microbiology ; Helicobacter pylori/*pathogenicity ; Humans ; *Virulence Factors

Background: The role of Helicobacter pylori live in digestive tract cause digestive disorder are confirmed. Objectives: To assess the relationship between seroprevalence of Helicobacter pylori (HP) in children and history of digestive disorders in children and their parents. Subjects and method: In this cross-sectional study, history of digestive disorders (recurrent epigastralgy at least 3 episodes in a duration at least 3 months, confirmed either by upper endoscopy or by gastric radiography with contrast or ameloration by treatment with anti - acid) was gathered using questionnaire with additional examination of individual health book, prescription or discharge certificate of a population of 818 children <15 years old in pediatric department, Bach Mai hospital and 369 children <18 in a rural commune. Seroprevalence was determined by ELISA with cut - off at 0.18 optic density. Results:Among in - patients, seroprevalence was 52.6% (20/38) in children with digestive history, significantly higher than 32.6% (254/780) in those who were without this history (p=0.013); risk for HP infection in children with the history was 4.8 higher than that in those who were without the history [OR (95% CI): 4.79 (1.62-9.16)), while the difference in HP seroprevalence was insignificant in children whose mother or father was with or without the history (p > 0.05). Among children in the community, the difference in HP seroprevalence of 72.7% (8/11) in children with and 55.0% (250/373) in those without the history was statistically insignificant (p>0.05). However, HP seroprevalence in children whose father or mother was with the history was of 71.8% (28/39) and 70.5% (31/44), respectivly, significantly higher than 43.1 % (94/318) and 45.6% (125/274) in those whose father or mother was without the history, respectively (p < 0.05). Risk for being HP seropositive in children whose father was with the history was 3.4 folds higher than those whose father was without the history [OR (95% CI): 3.36 (1.38-7.54)] and that in children whose mother was with the history was 2.9 folds higher than in those whose mother was without the history [OR (95% CI): 2.91 (1.41-5.26)]. Conclusion: It exsisted a discrepancy in relationship between HP seroprevalence in children and history of digestive disorders in 2 groups of population in the hospital and in the community, and further studies with larger size were warranted to better clarify this relationship.
Helicobacter pylori/ pathogenicity ; Stomach/ pathology ; Duodenal Diseases/ diagnosis ; pathology ; Child

OBJECTIVETo observe whether H. pylori inoculated by oral route could arrive in livers and cause liver inflammation as an independent etiological factor.

METHODSC57BL/6 mice were orally inoculated with H. pylori SS1 strains and fed for 8 months. H. pylori colonization and pathologic consequences were studied in the liver and gallbladder tissues of the mice; the blood, liver tissue and gastric mucosa were obtained and cultured for H. pylori growth; The bacterial DNA extracted from the liver, bile and blood was examined by nested PCR for H. pylori genes. 16S rRNA PCR amplicons were sequenced and compared with the sequencing results of 16S rRNA PCR amplicons of the bacteria cultured from gastric mucosa and the inoculated H. pylori SS1.

RESULTSThe bacterial DNA extracted from the liver, bile and blood of the infected mice was detected for H. pylori genes by nested PCR. Six of the 15 samples were positive (40%) in the liver, 6 of 10 samples in the bile (60%), and 2 of 10 samples in the blood (20%). Sequencing results of 16S rRNA PCR products of the livers showed 100% homogeneity when compared with the cultured H. pylori from gastric mucosa and inoculated H. pylori SS1. H. pylori was found in 4 liver tissues of the 15 infected mice (26.7%) and 6 in the gallbladders (40%). Infiltrations of lymphocyte cells along hepatic sinusoids and a lower degree infiltration around interlobular arteries and veins were observed; ballooning degeneration was also observed in some hepatocytes.

CONCLUSIONH. pylori inoculated by oral route could arrive in the liver and cause inflammation as an independent etiological factor. The routes which the microorganisms took to reach the livers may involve hematogenous and/or biliary system dissemination.

Animals ; Helicobacter Infections ; Helicobacter pylori ; pathogenicity ; Liver ; microbiology ; Male ; Mice ; Mice, Inbred C57BL ; Rats

OBJECTIVEThis article aimed to review the incidence of Helicobacter pylori (H. pylori) infection and its therapy.

DATA SOURCESRelevant articles published in English were identified by searching in PubMed from 2000 to 2013, with keywords "H. pylori". Important references from selected articles were also retrieved from Elsevier, Wiley, EBSCO, and SPRINGER. The Chinese articles published were searched from China National Knowledge Infrastructure (CNKI).

STUDY SELECTIONArticles about "prevalence", "gastric carcinoma", "peptic ulcer", "gastroesophageal reflux disease", "functional dyspepsia", "pathogenic mechanism", "therapy", "eradication rate", "antibiotic resistance", and "gene polymorphisms" were selected.

RESULTSThe decreased infection rates of H. pylori could also be linked to the changed disease spectrum, such as the decreased morbidity and recurrence rate of H. pylori-related peptic ulcer, and the increased morbidity of gastroesophageal reflux. Although different treatment regimens have been used for H. pylori infection, the H. pylori eradication rate declined gradually. Due to primary resistance to antibiotics, the gene polymorphism of host and infected strain, and the therapy regimes, H. pylori eradication became even more difficult.

CONCLUSIONSThe prevalence of H. pylori infection had been decreasing, but the rate of eradication failure has dramatically risen in many countries due to resistance to antibiotic. H. pylori therapy in clinical practice is becoming progressively more difficult.

Drug Resistance, Bacterial ; genetics ; Helicobacter Infections ; drug therapy ; epidemiology ; Helicobacter pylori ; drug effects ; genetics ; pathogenicity ; Humans

OBJECTIVES: Considering the geographic differences in the prevalence of virulence factors such as CagA or VacA of H. pylori isolated from Korean adults compared with those from western countries, the establishment of a mouse model infected with H. pylori isolated from Korean adults is needed to investigate the pathogenesis and to develop vaccines against H. pylori infection in Korea. The aim of this study was to establish the BALB/c mouse model infected with H. pylori isolated from Korean. METHODS: Six-week-old BALB/c mice were inoculated intragastrically with 10(9) CFU of H. pylori. Loss of glandular architecture, erosions and infiltration of inflammatory cells within the lamina propria compared with normal gastric mucosa were scrutinized. Evidence for H. pylori infection was assessed by rapid urease test of gastric mucosa and by microscopic examination using the H & E stain and Warthin-Starry silver stain. RESULTS: Rapid urease test was positive in 55% of all inoculated mice. Definite histologic changes and the evidence of H. pylori colonization were observed in the H. pylori infected group. Significant infiltration of inflammatory cells was observed 6 weeks after the last inoculation and the level of serum IgG against H. pylori was increased from 2 weeks after the last inoculation. CONCLUSIONS: The H. pylori isolated freshly from Korean adults could colonize the stomach of BALB/c mice and induce pathologic alterations that mimics human gastric diseases. This model would facilitate the investigations for the pathogenetic mechanisms of H. pylori infection.
Adult ; Animal ; Base Sequence ; DNA Primers/genetics ; Disease Models, Animal ; Female ; Gastric Mucosa/pathology ; Helicobacter Infections/pathology ; Helicobacter Infections/etiology* ; Helicobacter pylori*/pathogenicity ; Helicobacter pylori*/isolation & purification ; Helicobacter pylori*/genetics ; Human ; Korea ; Mice ; Mice, Inbred BALB C ; Virulence/genetics

OBJECTIVETo review the research progress on Type IV secretion system (T4SS) in Helicobacter pylori.

DATA SOURCESThe data used in this review were identified by searching of PUBMED (1995 - 2007) online resources using the key terms 'Type IV secretion system' and 'Helicobacter pylori'.

STUDY SELECTIONMainly original articles and critical reviews written by major pioneer investigators of this field were selected.

RESULTSThe research progress on T4SS in Helicobacter pylori was summarized. The structure and function was discussed.

CONCLUSIONST4SS is not only involved in toxin secretion and injection of virulence factors into eukaryotic host target cells, but also involved in horizontal DNA transfer to other bacteria and eukaryotic cells, through DNA uptake from or release into the extracellular milieu. It provides a new insight into the pathogenicity of Helicobacter pylori and a novel target for antimicrobials development. However, many challenges remain for us in understanding the biological role of T4SS in Helicobacter pylori.

Bacterial Proteins ; metabolism ; DNA-Binding Proteins ; Gene Transfer, Horizontal ; Helicobacter pylori ; genetics ; metabolism ; pathogenicity ; Multigene Family

In vitro subcultures of bacteria can lead to genetic and phenotypic changes. This study aimed at investigating the effect of repeated subcultures on the adhesion, motility, cytotoxicity, and gastric inflammation caused by Helicobacter pylori. H.pylori SS1 strain was subcultured 64 times on agar plates containing Brucella broth and 5% bovine calf serum. The adhesion, motility, cytotoxicity, and gastric inflammation produced in Mongolian gerbils were compared between the first and 64th subcultured strain. The adhesion rates, following 3 hr exposure of AGS cells to either the first strain or the 64th-transferred strain, were 21% and 12%, respectively. The motility of the 64th-transferred strain decreased significantly when compared to the 1st strain (9.1 mm vs. 15.1 mm). The cytotoxicity index tended to be higher in the first strain than in the 64th-transferred strain (73.7% vs. 69.2%). The initial infection rate on the gerbils showed no difference between the two strains. However, chronic gastric inflammation of the first strain-infected gerbils was somewhat more severe than that of the 64th-transferred strain-infected gerbils. Therefore, the use of repeatedly subcultured strains of H. pylori in virulence experiments can lead to different results from thoses of the original strain.
Animals ; Bacterial Adhesion ; Gastritis/immunology/*microbiology ; Gerbillinae ; Helicobacter Infections/immunology/*microbiology ; Helicobacter pylori/growth & development/*pathogenicity ; Male ; Virulence