Notes: Background. Phospholipids concentration in the gastric mucosa decreased in patients with Helicobacter pylori infection. The aim of this study is to examine the effects of eradication of H. pylori on decreasing the phospholipids concentration in the gastric mucosa in patients with gastric or duodenal ulcer.Materials and Methods. Phospholipids (phosphatidylcholine, phosphatidylethanolamine, and sphingonomyeline) were measured in biopsy specimens from the antrum and corpus using thin-layer chromatography. In H. pylori positive patients with gastric ulcer (n = 26) and duodenal ulcer (n = 13), and H. pylori negative controls (n = 20), the biopsy specimens were obtained before and 3 months after eradication. Eradication was performed using lansoprazole, amoxycillin, and clarithromycin.Results. Compared with the H. pylori negative control group, the concentrations of phosphatidylcholine and phosphatidylethanolamine decreased significantly in the gastric ulcer group in both antrum and corpus mucosa, and in the duodenal ulcer group in antrum mucosa. This decrease returned to the control level after eradication.Conclusions. This study demonstrates that the eradication of H. pylori in patients with peptic ulcer normalized the decrease of phosphatidylcholine and phosphatidylethanolamine in the gastric mucosa.

Notes: Background. Availability of the essential nutrient iron is thought to vary greatly in the gastric mucosa, and thus the human gastric pathogen Helicobacter pylori requires regulatory responses to these environmental changes. Bacterial iron-responsive regulation is often mediated by Ferric Uptake Regulator (Fur) homologs, and in this study we have determined the role of H. pylori Fur in regulation of H. pylori iron uptake.Methods. Wild-type H. pylori and fur mutant derivatives were compared after growth in iron-restricted and iron-replete conditions. Iron-uptake was measured using 55Fe-labeled iron, whereas gene expression was monitored at the transcriptional level using Northern hybridization and lacZ reporter gene fusions.Results. Iron-uptake and total cellular iron content were approximately five-fold increased in the fur mutant compared with the wild-type strain, which indicated that in the fur mutant iron-uptake is not repressed by excess iron. A comprehensive screening of all H. pylori genes encoding putative iron-uptake proteins indicated that some of these H. pylori genes are constitutively expressed, while others are iron- and Fur-regulated.Conclusions. Iron uptake in H. pylori is in part differently regulated compared with other bacteria, since in H. pylori some iron-uptake systems are constitutively expressed. However, other iron uptake systems of H. pylori display the iron- and Fur-mediated repression that is common in bacteria. Taken together, this Fur-mediated modulation of iron-uptake capacity may be a specific adaptation to the conditions in the human stomach, where iron starvation and iron overload can be encountered in relatively short time intervals.

Notes: Background. cag pathogenicity island is reported to be a major virulence factor of Helicobacter pylori. The aim of this study was to investigate the status of cag pathogenicity island genes and gastric histology in Korean children with H. pylori gastritis.Methods. Helicobacter pylori DNA was extracted from antral biopsy specimens from 25 children with H. pylori gastritis. Specific polymerase chain reaction assays were used for four genes of cag pathogenicity island. The features of gastritis were scored in accordance with the updated Sydney System.Results. cagA was present in 23 (92%) of 25 children, and cagE in 24 (96%). Twenty-two (88%) children were cagT positive and 19 (76%) virD4 positive. All of the selected genes of the cag pathogenicity island were present in 17 (68%) children and completely deleted in one child. There were no differences in neutrophil activity and chronic inflammation between children infected with intact cag pathogenicity island strains and those with partially or totally deleted-cag pathogenicity island strains.Conclusion. cag pathogenicity island is not a uniform, conserved entity in Korea. Completeness of cag pathogenicity island may not be the major factor to determine the severity of H. pylori gastritis in children.

Notes: Objective. Helicobacter pylori is implicated in gastric carcinogenesis through increased gastric epithelial cell turnover. In fact, high proportions of proliferating and apoptotic epithelial cells are found in H. pylori-infected gastric mucosa. E2F, a transcription factor, induces coordinated transactivation of a set of genes involved in cell cycle progression. The aim of this study was to investigate the expression of E2F in H. pylori-infected gastric mucosa and examine the correlation between such expression and gastric epithelial cell proliferation and apoptosis.Methods. Twenty-five patients with H. pylori-associated gastritis (HAG) and 13 control subjects negative for H. pylori were examined. E2F expression was studied in situ by Southwestern histochemistry, a method used to localize transcription factors. Labeled double-stranded oligo-DNA with specific consensus sequence for E2F binding sites was reacted with frozen sections from antral biopsy specimens obtained at endoscopy. Gastric epithelial cell proliferation was assessed by immunostaining of proliferating cell nuclear antigen (PCNA), while apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL). The percentages of epithelial cells with nuclear staining for PCNA and E2F were expressed as a positivity index (PI). The percentage of TUNEL-positive epithelial cells was defined as apoptotic index.Results. E2F was expressed in the nuclei of gastric epithelial cells within gastric pits. E2F PI in H. pylori-infected gastric mucosa was significantly higher than that in noninfected. Expression of E2F correlated well with PCNA-positive epithelial cells. We also demonstrated colocalization of PCNA with E2F expression in the same epithelial cells. Apoptotic index was also high in H. pylori-infected mucosa, and correlated with E2F PI.Conclusion. Our results demonstrated a significant increase in the expression of E2F in H. pylori-infected mucosa, which correlated with both the percentages of PCNA- and TUNEL-positive cells. Our results suggest that enhanced E2F expression in gastric mucosa may be involved in H. pylori-related gastric carcinogenesis through accelerated cell turnover.

Notes: Background. Bacteria have different characteristics in stimulation of human neutrophils to produce reactive oxygen species (ROS) and chemokines. This study examined the ability of Helicobacter pylori to induce production of ROS and chemokines by human neutrophils.Methods. H. pylori strains (1.5 × 108 CFU/ml) were cocultured with 5 × 104 neutrophils isolated from healthy subjects. Samples were incubated with human serum with or without IgG antibodies to H. pylori. ROS production was measured using luminol-dependent chemiluminescence (LmCL), and the concentrations of chemokines (IL-8, RANTES, MIP-1α and MCP-1) were measured by ELISA.Results. The mean of the highest LmCL (peak height; PH) value stimulated by H. pylori was 3318 in the absence of serum. PH increased to 4687 when incubated with anti-H. pylori antibody-positive sera (p 〈 .001) but antibody-negative sera did not affect LmCL response. The mean final concentration of IL-8 produced in the absence of serum was 142.6 pg/ml. Increased IL-8 production was seen by addition of antibody positive serum (p 〈 .01). IL-8 production was not significantly correlated with production of ROS. On the other hand, H. pylori stimulation did not induce neutrophil production of RANTES, MIP-1α or MCP-1.Conclusions. H. pylori was capable of inducing IL-8 production by human neutrophils, but not C-C chemokines. Production of C-X-C dominant chemokine by neutrophils is consistent with the pathological characteristics of H. pylori-induced gastritis, where persistent neutrophil infiltration is present.

Notes: Background. Even after partial gastrectomy, Helicobacter pylori may persist in the residual stomach but be less abundant in the bacterial load. H. pylori stool antigen is a reliable noninvasive tool to detect H. pylori infection in patients without gastrectomy. We thus test whether [1] the course of H. pylori eradication therapy could be diminished [2]; stool antigen can effectively detect H. pylori infection for the patients with gastrectomy.Methods. One hundred and eight patients who had undergone partial gastrectomy were enrolled to receive panendoscopy and provided stool samples for H. pylori stool antigen within 3 days after endoscopy. The H. pylori-infected patients were then randomized to receive either a 3- or 7-day triple therapy for H. pylori eradication. Six weeks later, to evaluate the success of H. pylori eradication, patients received a follow-up endoscopy and again provided stool samples for H. pylori stool antigen.Results. Seventy out of 108 patients, proven to have H. pylori infection, were evenly randomized into 3-day and 7-day therapy groups. The H. pylori eradication rates were similar between the 3-day and 7-day triple therapy (90.9 vs. 93.8%, p 〉 .05). Before therapy, the H. pylori stool antigen was 93% sensitive and 100% specific to detect H. pylori. After therapy, H. pylori stool antigen remain 100% sensitive and 88.3% specific to detect the failure of eradication therapy.Conclusion. H. pylori stool antigen is a highly reliable tool to screen H. pylori infection before therapy and to assess the success of eradication therapy in partial gastrectomy patients. To eradicate H. pylori infection for patients with partial gastrectomy, the duration of triple therapy can be shortened.

Notes: Background. It has been proposed that Helicobacter pylori infection is related to cardiovascular disease, although this has not been fully investigated. The aim of this study was to investigate whether H. pylori in-fection is associated with cardiovascular risk factors.Subjects and Methods. One thousand six hundred and fifty people undergoing annual medical checks at Shimane Institute of Health Science between September 1998 and August 1999 were enrolled. Gender, age, body mass index, habitual smoking and drinking, systolic and diastolic blood pressure, serum level of total cholesterol, triglyceride, high-density lipoprotein cholesterol (HDLC), blood glucose, leukocyte count and hemoglobin were compared between H. pylori seropositive and seronegative cases.Results. In H. pylori seropositive individuals, HDLC was significantly lower than that in seronegative individuals. After adjustment for possible confounding factors (gender, age, BMI, smoking and drinking habits), mean HDLC in H. pylori-seropositive and seronegative individuals were 56.1 and 58.2 mg/dl, respectively (p 〈 .005). The percentage of the elderly (over 50 years old) individuals with HDLC 〈 35 mg/dl in H. pylori seropositive and seronegative groups were 7.4% and 4.7%, respectively (p 〈 .001). In addition, the lower HDLC level was accompanied by an increased leukocyte count.Conclusion. Long-term infection with H. pylori may have an important role in decreasing the serum HDLC concentration.

Notes: Background. Nitric oxide (NO) generated by nitric oxide synthase (NOS) is known to be an important modulator of the mucosal inflammatory response. In this study, we questioned whether Helicobacter pylori infection could up-regulate the epithelial cell inducible NOS (iNOS) gene expression and whether NO production could show polarity that can be regulated by immune mediators.Materials and Methods. Human gastric epithelial cell lines were infected with H. pylori, and the iNOS mRNA expression was assessed by quantitative RT-PCR. NO production was assayed by determining nitrite/nitrate levels in culture supernatants. To determine the polarity of NO secretion by the H. pylori-infected epithelial cells, Caco-2 cells were cultured as polarized monolayers in transwell chambers, and NO production was measured.Results. iNOS mRNA levels were significantly up-regulated in the cells infected with H. pylori, and expression of iNOS protein was confirmed by Western blot analysis. Increased NO production in the gastric epithelial cells was seen as early as 18 hours postinfection, and reached maximal levels by 24 hours postinfection. The specific MAP kinase inhibitors decreased H. pylori-induced iNOS and NO up-regulation. After H. pylori infection of polarized epithelial cells, NO was released predominantly into the apical compartment, and IL-8 was released predominantly into basolateral compartment. The addition of IFN-γ to H. pylori-infected polarized epithelial cells showed a synergistically higher apical and basolateral NO release.Conclusion. These results suggest that apical NO production mediated by MAP kinase in H. pylori-infected gastric epithelial cells may influence the bacteria and basolateral production of NO and IL-8 may play a role in the tissue inflammation.

Notes: Background. Helicobacter pylori adhering to the human gastric epithelium causes gastric diseases such as ulcer, carcinoma and lymphoma. It is thus important to observe in detail both the surface of the epithelial cells and the H. pylori that adhered to it for the elucidation of H. pylori-induced diseases by scanning electron microscopy (SEM). Since the thick mucus layer blocks the observation of the cell surface and the bacteria, it is generally eliminated during the processing for SEM by roughly mechanical methods, but these treatments also demolish the ultrastructure of the cells. We studied the nonmechanical method for removal of mucus layer of gastric epithelium using pronase.Materials and Methods. To determine the optimal concentration of pronase, mucin was used as a substrate for inhibition of the viscosity. Pronase was added in 2% mucin at the concentration of 10, 50, 100, 500, 1000, 2000 or 5000 unit/ml and the flowing time of the mixture was measured. Based on the digestion experiment, biopsied specimens from 24 patients with dyspepsic symptoms were fixed in glutaraldehyde and then washed in rolling with different concentration of pronase. After the pretreatment by pronase, the specimens were treated according to the standard process for SEM.Results. We succeeded in removing the mucus layer on the surface of epithelial cells from the biopsied specimens fixed in glutaraldehyde by rinsing with 2000 unit/ml pronase for 24 hours.Conclusions. Using our digestive method without destroying the ultrastructure, the earliest stage which H. pylori has adhered onto the human gastric epithelium can be observed for the investigation of H. pylori-induced gastric disorders by SEM.