Pylori-negative Controls Research Articles

Knocking Down HN1 Blocks Helicobacter pylori-Induced Malignant Phenotypes in Gastric Mucosal Cells and Inhibits Gastric Cancer Cell Proliferation, Cytoskeleton Remodeling, and Migration.

Helicobacter pylori (H. pylori) is implicated in the aberrant proliferation and malignant transformation of gastric mucosal cells, heightening the risk of gastric cancer (GC). HN1 is involved in the development of various tumors. However, precise mechanistic underpinnings of HN1 promoting GC progression in H. pylori remain elusive. The study collected 79 tissue samples of GC patients, including 47 with H. pylori-positive GC and 32 H. pylori-negative controls. Using human gastric epithelial cells (GES-1) and human gastric adenocarcinoma cells (HGC-27), the effect of overexpression / knocking down of HN1 and H. pylori infection was evaluated on cell function (proliferation, migration, apoptosis), cytoskeleton, and expression of cell malignant phenotype factors that promote the malignant biological behavior of cancer cells. The expression of HN1 in GC tissues is higher than that in paracancerous tissue and is closely related to infiltration, lymphatic metastasis, distant metastasis, survival, and H. pylori infection. Downregulation of HN1 effectively hinders the ability of H. pylori strains 26695 and SS1 to promote migration of GES-1 and HGC-27 cells, while lowering the expression of key indicators associated with malignant phenotype. Downregulated GSK3B, β-catenin, and Vimentin after knockdown Integrinβ1, but HN1 expression remained largely unchanged, when HN1 and Integrinβ1 were knocked down, GSK3B, β-catenin, and Vimentin expression were considerably reduced. Our research demonstrated the crucial role of HN1 in H. pylori-induced acquisition of a malignant phenotype in GES-1 cells. Knockdown of HN1 blocked the pathogenic mechanism of H. pylori-induced GC and downregulated the expression of GSK3Β, β-catenin and Vimentin via Integrin β1.

Relation of CRP gene variants to altered risk of Helicobacter pylori - associated chronic gastritis: A case-control study in Tunisia

BackgroundWe investigated the association between CRP variants and chronic gastritis in H. pylori-infected patients at the allele, genotype, and haplotype levels. This was also assessed according to serum hs-CRP levels. MethodsStudy subjects consisted of 77 H. pylori-infected patients and 96 H. pylori-negative controls. Genotyping of the CRP rs1572970, rs876537, rs2794520, rs2808630, rs1130864, rs1417938, rs7553007, and rs4285692 variants were analyzed by real-time PCR. ResultsSignificantly higher MAF and increased risk of chronic gastritis were associated with rs1130864, rs1417938, and rs7553007, which persisted after controlling for key covariates. Significant differences in the genotype distribution of rs1130864, rs1417938, and rs7553007 were also seen between H. pylori-infected patients and healthy controls. Increased risk of H. pylori-associated chronic gastritis was associated with carriage of rs1130864 C/T, and more with T/T genotype carriers, as well as with rs1417938 T/A and A/A genotype carriers. Functionally, the distribution of rs1130864 and rs1417938 genotypes were significantly different between H. pylori-infected patients and controls in the low hs-CRP (<6 mg/L) group. CRP haplotype analysis identified Block 1 (rs1572970, rs876537, rs2794520), and Block 2 (rs2808630, rs1130864, rs1417938) associated with H. pylori infection. Haplotypes ACC (Block 1) and TTA and TTT (Block 2) were positively associated with H. pylori-associated chronic gastritis with low hs-CRP levels. ConclusionAltered serum levels of hs-CRP, stemming in part from the presence of specific genetic variants in CRP gene, modulate the risk of H. pylori infection.

Long-term risk of upper gastrointestinal bleeding after Helicobacter pylori eradication: a population-based cohort study.

The long-term effects of H. pylori eradication in preventing upper GI bleeding (UGIB) remains unknown. To determine the long-term risks of UGIB after H. pylori eradication METHODS: We included all patients who had received clarithromycin-containing triple therapy for the treatment of H. pyliori infection between 2003 and 2012, without subsequent need for re-treatment. We included a propensity score (PS)-matched endoscopy cohort of H. pylori-negative patients as controls. The primary endpoint was the risk of subsequent UGIB. A multivariable Cox model was used to compute the hazard ratio (HR) of UGIB. We included 62738 H. pylori-eradicated and 62738 PS-matched H. pylori-negative patients, with a median follow-up of 8.1years (IQR 5.5-10.6). The incidence of UGIB was 20.8 (95% CI 19.5-22.1) and 13.6 (95% CI 12.7-14.7) per 10000 person-years in H. pylori-eradicated and H. pylori-negative patients, respectively. Compared to controls, H. pylori-eradicated patients had a significantly higher risk of UGIB (HR: 1.65, 95% CI 1.49-1.83). The risk of UGIB in H. pylori-eradicated patients increased after the first 2 years of follow up (HR: 2.18, 95% CI 1.91-2.49). Age-stratified analysis showed that patients >45years had higher UGIB risk, even after eradication. Despite H. pylori eradication, the long-term risk of UGIB was still higher than in H. pylori-negative control subjects. The protective effects of eradication therapy in preventing UGIB appeared to be limited to younger patients, and to within the first 2 years after eradication.

The gastric microbiota in patients with Crohn\u2019s disease; a preliminary study

The gastric microbiota in Crohn’s disease (CD) has not been studied. The purpose of the study was to evaluate differences of stomach microbiota between CD patients and controls. DNA was extracted from gastric mucosal and fluid samples, from 24 CD patients and 19 controls. 16S rRNA gene sequencing identified 1511 operational taxonomic units (OTUs), of which 239 passed the low abundance and low variance filters. All but one CD patients were HP negative. Fifteen bacterial phyla were identified in at least one mucosal or fluid site. Of these, Bacteroidota and Firmicutes accounted for 70% of all phyla. Proteobacteria, Actinobacteriota, and Fusobacteriota combined accounted for 27%. There was significant difference in the relative abundance of Bacteroidota, Proteobacteria, Fusobacteriota, and Campilobacterota between CD patients and controls only in gastric corpus samples. In gastric liquid, there was a significant difference only in Actinobacteriota. Pairwise comparison identified 67 differentially abundant OTUs in at least one site. Of these, 13 were present in more than one comparison, and four differentiating OTUs (Neisseriaceae, Neisseria, Absconditabacteriales, and Microbacteriaceae) were identified at all tested sites. The results reveal significant changes in gastric microbial profiles (beta diversity, phylum, and individual taxa levels) between H. pylori-negative CD patients and controls.

Functionally significant polymorphisms of the MMP-9 gene are associated with peptic ulcer disease in the Caucasian population of Central Russia

This study analyzed the association of functionally significant SNPs of matrix metalloproteinase (MMP) genes in the development of peptic ulcer disease (PUD) in Caucasians from Central Russia. Ten SNPs of the MMP-1, MMP-2, MMP-3, MMP-8, and MMP-9 genes were analyzed for association with PUD in a cohort of 798 patients with PUD (including 404 H. pylori-positive and 394 H. pylori-negative) and 347 H. pylori-negative controls using logistic regression and assuming the additive, recessive, and dominant genetic models. The variants of MMP-1, MMP-2, MMP-3, and MMP-8 did not manifest any significant associations with the diseases. Five SNPs of the MMP-9 gene demonstrated such association. Allele G of the rs17576 MMP-9 locus conferred a higher risk for PUD (ORadj = 1.31, pperm = 0.016), haplotype AACG of loci rs17576-rs3787268-rs2250889-rs17577 of the MMP-9 gene decreased risk for PUD (ORadj = 0.17, pperm = 0.003). Also, allele C of rs3918249, allele G of rs17576 and haplotype CG of rs3918249-rs17576 of the MMP-9 gene increased risk for H. pylori-positive PUD (ORadj = 1.82, pperm = 0.002; ORadj = 1.53–1.95 pperm = 0.001–0.013 and ORadj = 1.49 pperm = 0.009 respectively). The above loci and 50 linked to them possess significant regulatory effects and may affect the alternative splicing of four genes and the expression of 17 genes in various organs and tissues related to the PUD pathogenesis.

Ultrasonographic assessment of femoral cartilage thickness in patients with Helicobacter pylori infection.

Helicobacter pylori is a major cause of gastritis and a potential trigger of inflammatory disease. The effect of Hpylori infection on distal femoral cartilage has yet to be evaluated. The aim of this study was to evaluate femoral cartilage thickness in patients with Hpylori infection and to find whether this infection affects femoral cartilage thickness. This cross-sectional study included 199 patients. To measure the thickness of femoral articular cartilage, 99 patients with Hpylori infections and 100 with Hpylori-negative controls were enrolled into two groups. The measurements were made using linear probe ultrasonography with the patients in supine positions and their knees in maximum flexion. Demographic, clinical, endoscopic and laboratory data were collected for all patients. Both the right and left femoral condyles had thinner cartilage thickness in the Hpylori-positive group than in the Hpylori-negative group (P=.016, P=.036). For the intercondylar area and lateral femoral condyles, although the Hpylori-positive patients had thinner femoral cartilage thickness than the Hpylori-negative individuals for both extremities, this finding was not statistically significant (P>.05). Femoral cartilage was thinner in patients with Hpylori than patients without Hpylori for right and left medial femoral condyles. This study suggests that Hpylori infections may affect femoral cartilage thickness and potentially increase the risk of cartilage degeneration.

Serum level of some micronutrients in children infected with Helicobacter pylori

BackgroundHelicobacter pylori (H. pylori) proved to be highly prevalent all over the world. H. pylori may modify the absorption of many nutrients. Studies have suggested that, beyond iron, H. pylori infection may affect the homeostasis of other micronutrients such as vitamins and trace elements. Our study’s aim was to assess the effect of H. pylori infection on some blood micronutrient level including zinc, selenium, vitamin C, and vitamin B12 in children with chronic or recurrent unexplained dyspeptic symptoms and/or non-variceal hematemesis.ResultsA cross-sectional case-control study was carried out in 32 children (4–18 years) with chronic or recurrent unexplained dyspeptic symptoms and/or non-variceal hematemesis. Patients were divided according to the results histopathology and rapid urease test into two groups, H. pylori-positive patients (18 patients) and H. pylori-negative patients (14 patients). Another control group of 18 children was included. Serum levels of zinc, selenium, vitamin C, and vitamin B12 were measured in all children. Prevalence of H. pylori infection was 56.2%. The mean serum zinc levels were significantly lower in H. pylori-positive cases than in control group (84.2 ± 13.85 versus 94.6 ± 6.52 with P = 0.009) and lower than in H. pylori-negative cases but not statistically significant (84.2 ± 13.85 versus 92.2 ± 8.53 with P = 0.054). The mean serum vitamin C levels were significantly lower in H. pylori-positive cases than in negative cases and control group (220.7 ± 46.16 versus 305.1 ± 28.83 and 313.1 ± 31.43 with P < 0.0001). The mean serum vitamin B12 levels were significantly lower in H. pylori-positive cases than in negative cases and control group (167.8 ± 76.98 versus 290.1 ± 69.92 and 326.1 ± 38.67 with P < 0.0001). The mean serum selenium level was slightly higher in H. pylori-positive patients than in H. pylori-negative patients and control group but not statistically significant (118.2 ± 11.13 versus 112.1 ± 8.69 and 113.1 ± 13.76 with P = 0.096, 0.243 respectively).ConclusionHelicobacter pylori infection in children has a significant negative effect on the serum levels of zinc, vitamin C, and vitamin B12.

Helicobacter pylori Eradication Can Reverse the Methylation-Associated Regulation of miR-200a/b in Gastric Carcinogenesis.

Background/AimsEpigenetic change is one of the mechanisms that regulates the expression of microRNAs (miRNAs) and is known to play a role in Helicobacter pylori-associated gastric carcinogenesis. We aimed to evaluate the epigenetic changes of miR-200a/b in H. pylori-associated gastric carcinogenesis and restoration after eradication.MethodsThe expression and methylation levels of miR-200a/b were evaluated in gastric cancer (GC) cell lines, human gastric mucosa of H. pylori-negative and -positive controls, and H. pylori-positive GC patients. Next, the changes in the expression and methylation levels of miR-200a/b were compared between H. pylori-eradication and H. pylori-persistence groups at 6 months. Real-time reverse transcription-polymerase chain reaction was conducted to investigate the miRNA expression levels, and MethyLight was performed to assess the methylation levels.ResultsIn the GC cell lines, the level of miR-200a/b methylation decreased and the level of expression increased after demethylation. In the human gastric mucosa, the miR-200a/b methylation levels increased in the following group order: H. pylori-negative control group, H. pylori-positive control group, and H. pylori-positive GC group. Conversely, the miR-200a/b expression levels decreased in the same order. In the H. pylori-persistence group, no significant changes were observed in the methylation and expression levels of miR-200a/b after 6 months, whereas the level of methylation decreased and the level of expression of miR-200a/b increased significantly 6 months in the H. pylori-eradication group.ConclusionsEpigenetic alterations of miR-200a/b may be implicated in H. pylori-induced gastric carcinogenesis. This field defect for cancerization is suggested to be improved by H. pylori eradication.

Relationship between Helicobacter pylori infection and osteoporosis: a systematic review and meta-analysis

ObjectivesMany studies have explored the association between Helicobacter pylori infection and osteoporosis. However, the results remain controversial. Therefore, we performed this systematic review and meta-analysis to evaluate the association between...

Gastric Mucosal Atrophy Impedes Housekeeping Gene Methylation in Gastric Cancer Patients.

PurposeHelicobacter pylori infection induces phenotype-stabilizing methylation and promotes gastric mucosal atrophy that can inhibit CpG-island methylation. Relationship between the progression of gastric mucosal atrophy and the initiation of CpG-island methylation was analyzed to delineate epigenetic period for neoplastic transformation.Materials and MethodsNormal-appearing gastric mucosa was biopsied from 110 H. pylori–positive controls, 95 H. pylori–negative controls, 99 gastric cancer patients, and 118 gastric dysplasia patients. Gastric atrophy was assessed using endoscopic-atrophic-border score. Methylation-variable sites of eight CpG-island genes adjacent to Alu (CDH1, ARRDC4, PPARG, and TRAPPC2L) or LTR (MMP2, CDKN2A, RUNX2, and RUNX3) retroelements and stomach-specific TFF3 gene were analyzed using radioisotope-labeled methylation-specific polymerase chain reaction.ResultsMean ages of H. pylori–positive controls with mild, moderate, and severe atrophy were 51, 54, and 65 years and those of H. pylori–associated TFF3 overmethylation at the three atrophic levels (51, 58, and 63 years) tended to be periodic. Alu-adjacent overmethylation (50 years) was earlier than TFF3 overmethylation (58 years) in H. pylori–positive controls with moderate atrophy. Cancer patients with moderate atrophy showed late Alu-adjacent (58 years) overmethylation and frequent LTR-adjacent overmethylation. LTR-adjacent overmethylation was frequent in cancer (66 years) and dysplasia (68 years) patients with severe atrophy.ConclusionAtrophic progression is associated with gastric cancer at moderate level by impeding the initiation of Alu-adjacent methylation. LTR-adjacent methylation is increased in cancer patients and subsequently in dysplasia patients.

Helicobacter pylori Is Associated with miR-133a Expression through Promoter Methylation in Gastric Carcinogenesis

Background/AimsTo investigate whether Helicobacter pylori eradication can reverse epigenetic silencing of microRNAs (miRNAs) which are associated with H. pylori-induced gastric carcinogenesis.MethodsWe examined expression and promoter methylation of miR-34b/c, miR-133a, let-7a, and let-7i in gastric cancer cell line, before/after demethylation. Among them, epigenetically controlled miRNAs were identified. Their expression and promoter methylation was examined in human tissues of H. pylori-positive gastric cancer (T), H. pylori-positive gastritis (H), and H. pylori-negative controls (C). We also compared changes of miRNA expression and promoter methylation in H. pylori-positive patients who were endoscopically treated for early gastric cancer, between baseline and 1 year later according to eradication status.ResultsIn gastric cancer cell line, miR-34b/c and miR-133a showed epigenetic silencing. In human tissues, miR-34b/c and miR-133a showed serial increase of promoter methylation in order of C, H, and T (all, p<0.01), and the miR-133a expression showed serial decrease (C vs H, p=0.02; H vs T, p=0.01; C vs T, p<0.01) while miR-34b and miR-34c expressions did not. H. pylori eradication induced decrease of methylation (p<0.01) and increase of miR-133a expression (p=0.03), compared with noneradication group.ConclusionsThis result suggests H. pylori eradication could reverse methylation-silencing of miR-133a which is involved in H. pylori-induced gastric carcinogenesis.

Helicobacter pylori-induced modulation of the promoter methylation of Wnt antagonist genes in gastric carcinogenesis

This study aimed to investigate the changes in the promoter methylation and gene expression of multiple Wnt antagonists between the chronic infection and eradication of Helicobacter pylori (H. pylori) in gastric carcinogenesis. The levels of methylation and corresponding mRNA expression of seven Wnt antagonist genes (SFRP1, -2, -5, DKK1, -2, -3, WIF1) were compared among the patients with H. pylori-positive gastric cancers (GCs), and H. pylori-positive and H. pylori-negative controls, by quantitative MethyLight assay and real-time reverse transcription (RT)-polymerase chain reaction (PCR), respectively. The changes of the methylation and expression levels of the genes were also compared between the H. pylori eradication and H. pylori-persistent groups 1year after endoscopic resection of GCs. The methylation levels of SFRP and DKK family genes were significantly increased in the patients with H. pylori-positive GCs and followed by H. pylori-positive controls compared with H. pylori-negative controls (P<0.001). SFRP1, -2, and DKK3 gene expression was stepwise downregulated from H. pylori-negative controls, H. pylori-positive controls, and to H. pylori-positive GCs (P<0.05). Among the Wnt antagonists, only the degrees of methylation and downregulation of DKK3 were significantly reduced after H. pylori eradication (P<0.05). Epigenetic silencing of SFRP and DKK family genes may facilitate the formation of an epigenetic field during H. pylori-associated gastric carcinogenesis. The epigenetic field may not be reversed even after H. pylori eradication except by DKK3 methylation.

Combination of Helicobacter pylori infection and the interleukin 8 \u2013251\xa0T\xa0>\xa0A polymorphism, but not the mannose-binding lectin 2 codon 54\xa0G\xa0>\xa0A polymorphism, might be a risk factor of gastric cancer

BackgroundMannose-binding lectin (MBL) acts in the innate immune response to Helicobacter pylori. Interleukin 8 (IL-8) is a potent cytokine produced by gastric epithelial cells in response to H. pylori. We aimed to investigate whether polymorphisms in MBL2 and IL-8 influence susceptibility to H. pylori infection, and the associations of these polymorphisms with the risk of gastroduodenal diseases in a Korean population.MethodsWe consecutively enrolled 176 H. pylori-negative control subjects, 221 subjects with H. pylori-positive non-atrophic gastritis, 52 mild atrophic gastritis (AG), 61 severe AG, 175 duodenal ulcer, and 283 gastric cancer (GC). Allele-specific PCR-RFLP was conducted for polymorphisms in MBL2 exon 1 (codon 52, 54, and 57) and IL-8 -251 T > A. IL-8 levels in gastric mucosal tissues and serum MBL levels were measured by enzyme-linked immunosorbent assay.ResultsMBL2 exon 1 polymorphic variants were found only in codon 54, and the allele frequencies did not differ significantly between the control and disease groups. Although serum MBL levels in codon 54 A/A mutants were markedly low, it did not influence susceptibility to H. pylori infection or the risk of gastroduodenal diseases. IL-8 levels were significantly different between T/T wild type, T/A heterozygote, and A/A mutant genotypes. IL-8 -251 A allele carriers (A/A + T/A) showed increased IL-8 levels, and were significantly associated with the risk of severe AG and GC.ConclusionsWe suggest that a combination of H. pylori infection and the IL-8 -251 T > A polymorphism might increase the risk of severe AG and GC in a Korean population.

Long-term follow-up of pepsinogen I/II ratio after eradication of Helicobacter pylori in patients who underwent endoscopic mucosal resection for gastric cancer

BackgroundAlthough the pepsinogen I/II (PGI/II) ratio after Helicobacter pylori eradication is recovered at short-term follow-up, long-term follow-up studies of PGI/II are rare. MethodsA total of 773 patients with gastric cancer who underwent endoscopic resection and pepsinogen and H. pylori tests were enrolled. H. pylori was eradicated in these patients. Endoscopic and pepsinogen tests were performed every year. A low PGI/II ratio was defined as ≤3. ResultsThe PGI/II ratio was higher in non-infected patients (n=275, 4.99) than infected patients (n=498, 3.53). After H. pylori eradication, the PGI/II ratio increased to 5.81 and 5.63 after 1 and 2 years (each p<0.05). The PGI/II ratio in the non-eradication group decreased to 3.94 and 2.75 after 1 and 2 years. The PGI/II ratio in the H. pylori eradication group became similar to that of the H. pylori-negative group at 3 (4.48 vs. 4.34), 4 (4.88 vs. 4.34), and 5 years (4.89 vs. 4.23). The adjusted odds ratios for a lower PG I/II ratio in the non-eradication group compared to the eradication group were 4.78 (95% CI 2.15–10.67) after 1year and 8.13 (95% CI 2.56–25.83) after 2 years. ConclusionsAfter H. pylori eradication, the PGI/II ratio increased and was similar to that of H. pylori-negative controls for up to 5 years of follow-up.

Impact of Helicobacter pylori Eradication on Absolute Telomere Length in Gastric Mucosa

Background and study aim: This study proposed to assess the relation between absolute telomere lengths (TLs) in gastric mucosa and Helicobacter pylori (H. pylori) infection and study the impact of (H. pylori) eradication therapy on TLs. Patients and Methods: This study was conducted on (42) subjects divided into two groups, group I: included (17) H. pylori negative cases served as control group, group II: included (25) H. pylori positive patients. Absolute TLs was measured in base pairs (bp) in gastric mucosa and analyzed by real time polymerase chain reaction (RT-PCR) in all groups and re-evaluated in H. pylori positive patients 4 weeks after eradication therapy. Results: Prior to eradication therapy, there was highly significant shortening (P<0.001) in TLs (bp) in gastric mucosa of H. pylori positive patients compared to H. pylori negative controls. While there was highly significant elongation was observed after H. pylori eradication therapy in H. pylori positive patients (P < 0.001). There was significant negative correlation between TLs and ages of patients (P<0.001) while there was no significant relation between TLs and sex (P= 0.5) before and after eradication therapy. Conclusion: H. pylori positive patients had significantly shorter TLs than H. pylori negative controls. TLs were increased after H. pylori eradication therapy in H. pylori positive cases. This finding may indicate the importance of H. pylorieradication to avoid the development of gastric cancer by its effect on TLs.

Helicobacter pylori infection: a risk factor for insulin resistance in nonobese nondiabetic individuals

Background Helicobacter pylori is a pathogenic bacterium that has been linked to many disorders such as cardiovascular diseases, diabetes mellitus, and dyslipidemia. However, whether it is associated with insulin resistance still needs to be evaluated. In this work we aimed to delineate the possible relation of H. pylori infection with insulin resistance in nonobese nondiabetic patients. Patients and methods The study was carried out on 80 individuals who were divided into two groups. Forty patients were diagnosed to have H. pylori and 40 healthy volunteers formed the control group. All were subjected to history taking, clinical examination, routine laboratory investigations, evaluation of H. pylori immunoglobulin G level, and assessment of fasting blood glucose and fasting insulin level to calculate homeostasis model assessment of insulin resistance. Results There was a significant increase in C-reactive protein in H. pylori-positive patients when compared with H. pylori-negative controls. Also a significant positive correlation was found between homeostasis model assessment of insulin resistance and each of fasting blood glucose, fasting insulin, and C-reactive protein in both groups. Conclusion H. pylori infection was strongly associated with insulin resistance in nonobese, nondiabetic patients.

Relationship between ghrelin,Helicobacter pyloriand gastric mucosal atrophy in hemodialysis patients

AIMTo investigate the relationship between plasma ghrelin level, Helicobacter pylori (H. pylori) infection status and the severity of atrophy in hemodialysis patients.METHODSOne hundred eights patients who received hemodialysis and 13 non-hemodialysis H. pylori-negative controls underwent gastroduodenoscopy to evaluate the severity of gastric atrophy. Serum levels of pepsinogen (PG) were measured as serum markers of gastric atrophy. H. pylori infection was evaluated by anti-H. pylori IgG antibody, rapid urease test and culture test. We classified H. pylori infection status as non-infection, present infection and past infection. In addition, plasma acyl-ghrelin and desacyl-ghrelin levels were measured by enzyme-linked immunosorbent assay.RESULTSInfection rate of H. pylori was 45.4% (49/108). Acyl-ghrelin level in the non-infection group (39.4 ± 23.0 fmol/mL) was significantly higher than in the past (23.4 ± 19.9 fmol/mL, P = 0.005) and present infection groups (19.5 ± 14.0 fmol/mL, P < 0.001). Furthermore, desacyl-ghrelin level in the non-infection group (353.2 ± 190.2 fmol/mL) was significantly higher than those in the past (234.9 ± 137.5 fmol/mL, P = 0.008) and present infection groups (211.8 ± 124.2 fmol/mL, P < 0.001). Acyl-ghrelin was positively correlated with the PG I level and PG I/II ratio (|R| = 0.484, P < 0.001 and |R| = 0.403, P < 0.001, respectively). Both ghrelins were significantly decreased in accordance with the progress of endoscopic atrophy (both P < 0.001) and acyl-ghrelin was significantly lower in patients with mild, moderate and severe atrophy (24.5 ± 23.1 fmol/mL, 20.2 ± 14.9 fmol/mL and 18.3 ± 11.8 fmol/mL) than in those with non-atrophy (39.4 ± 22.2 fmol/mL, P = 0.039, P = 0.002 and P < 0.001, respectively).CONCLUSIONIn hemodialysis patients, plasma ghrelin level was associated with the endoscopic and serological severity of atrophy related to H. pylori infection.

760 Confocal Endomicroscopy Demonstrates Increased Intestinal Permeability and Gut Dysfunction in Patients With Acute and Chronic Pancreatitis

Introduction Increased intestinal permeability and endotoxaemia occur in acute pancreatitis (AP) but have yet to be confirmed in chronic pancreatitis (CP). Confocal endomicroscopy (CEM) is a novel technology that has identified epithelial gaps and leakage of intravenously administered fluorescein from small intestinal mucosa in inflammatory bowel diseases. We aimed to determine intestinal permeability changes in AP and CP using CEM, assessing associations with endotoxaemia, circulating cytokines and alterations in duodenal flora. Method 182 patients were recruited: 35 mild AP; 11 moderate AP; 8 severe AP (Determinant Based Classification); 47 CP (27 surgically managed, 20 conservatively managed); 33 chronic liver disease and 48 non-ulcer dyspepsia (from whom 14 healthy H. pylorinegative controls were identified). Blood was sampled and duodenal fluid aspirated for culture. CEM was performed in consenting patients and fluorescein leakage scored by two independent blinded investigators. Plasma endotoxin antibodies, serum cytokine concentrations and lactulose:mannitol ratios were measured; D-amino oxidase concentrations were assayed in AP patients undergoing CEM. Results Fluorescein leakage from epithelial villi at CEM and lactulose:mannitol ratios were significantly higher in AP patients (p = 0.0346 and p = 0.046 respectively) and surgically managed CP (p = 0.032, p = 0.030) compared to healthy controls. Patients with AP more frequently showed positive duodenal bacterial cultures than controls (p = 0.004); positive duodenal cultures were associated with fluorescein leakage (p = 0.035). Plasma IgM and IgG concentrations were decreased in AP compared to controls, most markedly in severe AP, and multiple cytokines showed significantly increased concentrations in severe AP. D-amino oxidase enzyme concentrations were significantly increased in those AP patients who showed fluorescein leakage at CEM (p = 0.035). Conclusion CEM identified increased intestinal permeability in AP and surgically managed CP, associated with endotoxaemia, increased serum inflammatory cytokines and D-amino oxidase. These changes were most marked in severe AP. The association of fluorescein leakage with duodenal bacterial proliferation in AP indicates major gut dysfunction that may account for bacterial translocation via epithelial gaps, contributing to AP severity. Disclosure of interest None Declared.

Slow Overmethylation of Housekeeping Genes in the Body Mucosa Is Associated with the Risk for Gastric Cancer

Helicobacter pylori infection increases age-related diverse overmethylation in gene-control regions, which increases the risk of gastric cancer. The H. pylori-associated overmethylation changes subsequently disappear when gastric atrophy and cancer develop. To identify cancer-risk epigenotypes, we traced dynamic methylation changes in the background mucosa of the stomach depending on the extent of gastric atrophy. Paired biopsy specimens were obtained from the noncancerous antrum and body mucosa of 102 patients with cancer and 114 H. pylori-positive and 112 H. pylori-negative controls. The grade of gastric atrophy was evaluated using the endoscopic atrophic border score. The methylation-variable sites at the CpG-island margins and near the transcriptional start sites lacking CpG islands were semiquantitatively analyzed by radioisotope-labeling methylation-specific PCR. We selected eight housekeeping genes adjacent to Alu (CDH1, ARRDC4, PPARG, and TRAPPC2L) or LTR retroelements (MMP2, CDKN2A, RUNX2, and RUNX3) and eight stomach-specific genes (TFF2, PGC, ATP4B, TFF1, TFF3, GHRL, PGA, and ATP4A). Analysis of age-related methylation in the H. pylori-positive controls revealed slow overmethylation in the body and in the LTR-adjacent genes. A high-frequency overmethylation defined based on the slowly overmethylated genes was frequently observed in the body of patients with gastric cancer with open-type atrophy (OR, 12.7; 95% confidence interval, 3.2-49.8). The rapidly changing methylation of Alu-adjacent genes was barely increased in the antrum of patients with gastric cancer. Among diverse methylation changes associated with H. pylori infection, an increase in slowly changing methylation could serve as a cancer-risk marker.

The effect of Helicobacter pylori infection and eradication in patients with gastro-oesophageal reflux disease: A parallel-group, double-blind, placebo-controlled multicentre study.

This study aimed to resolve controversy regarding the effects of Helicobacter pylori eradication therapy and H. pylori infection in gastro-oesophageal reflux disease. A randomized, double-blind, multicentre trial was performed in patients presenting with reflux symptoms. H. pylori-positive patients were randomized to receive either antibiotics or placebo for 7 days. H. pylori-negative patient controls received placebo. All received esomeprazole 20 mg b.d. for 7 days, followed by 40 mg o.d. to complete an 8-week course, and were followed up for 32 weeks by telephone. In this study, 198/589 (34%) patients were H. pylori-positive and 113 H. pylori-negative patients served as controls. Baseline endoscopy revealed 63% Los Angeles grade 0A and 37% Los Angeles grade BCD oesophagitis with no difference between patient groups. Symptom improvement on esomeprazole was seen in 89%. H. pylori eradication was successful in 82%. H. pylori eradication had no effect on symptomatic relapse (hazard ratio 1.15, 95% CI 0.74-1.8; p = 0.5). Overall, H. pylori-positive patients had a lower probability of relapse compared to H. pylori-negative controls (hazard ratio 0.6, 95% CI 0.43-0.85; p = 0.004). Relapse hazard was modulated also by oesophagitis grade (BCD vs. 0A, hazard ratio 2.1, 95% CI 1.5-3.0). Relapse of gastro-oesophageal reflux disease symptoms after a course of high dose acid suppression took longer for H. pylori-positive patients than H. pylori-negative controls; however eradication therapy had no effect on the risk of relapse; ClincialTrials.gov number, NCT00574925.