• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2499-2506
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• 2016

Background: Gastric cancer (GC) is the second leading cause of cancer-related death worldwide. Several environmental, genetic and epigenetic factors have been suggested to have a role in GC development. Epigenetic mechanisms like histone changes and promoter hyper-methylation are now being increasingly studied. Associations between methylation of many gene promoters with the risk of gastric cancer have been investigated worldwide. Such aberrant methylation may result in silencing of specific genes related to cell cycling, cell adhesion, apoptosis and DNA repair. Thus this molecular mechanism might have a key role in proliferation and migration of cancerous cells. Materials and Methods: In this review article we included studies conducted on DNA methylation and gastric cancer in Iranian populations. Using Science direct, Pubmed/PMC, Springer, Wiley online library and SciELO databases, all published data until 31 January 2016 were gathered. We also searched Science direct data base for similar investigations around the world to make a comparison between Iran and other countries. Results: By searching these databases, we found that the association between methylation of seven gene promoters and gastric cancer had been studied in Iran until 31 January 2016. These genes were p16, hLMH1, E-cadherin, CTLA4, $THR{\beta}$, mir9 and APC. Searching in science direct database also showed that 92 articles had been published around the world till January 2016. Our investigation revealed that despite the importance of GC and its high prevalence in Iran, the methylation status of only a few gene promoters has been studied so far. More studies with higher sample numbers are needed to reveal the relation of methylation status of gene promoters to gastric cancer in Iran. Conclusions: Further studies will be helpful in identifying associations of DNA methylation in candidate genes with gastric cancer risk in Iranian populations.

• Biomolecules & Therapeutics
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• v.3 no.1
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• pp.72-79
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• 1995

The antiulcer effects of newly synthesized prostaglandin derivatives were investigated in various experimental ulcer models and on gastric secretion in rats. HK-3 and HK-4, PG $E_2$derivatives, prevented the formation of acute gastric ulcer induced by ethanol or aspirin in pylorus-ligated rats. The ulcer formation was moderately inhibited by HK-1 and HK-2, PG $F_{2{\alpha}}$ derivatives, and aggravated by SK-1, SK-2 and SK-3, PG $F_{2{\alpha}}$ derivatives. HK-3 and HK-4 reduced the volume, acid output and pepsin output of gastric juice in pylorus-ligated rats. The gastric perfusion with physiologic saline(pH 6.0) showed relatively constant acid secretion and indomethacin increased the acid secretion. The acid secretion was markedly decreased by PG $E_2$but PG $F_{2{\alpha}}$ caused little change. Prostaglandin derivatives, especially HK-3 arid HK-4, significantly inhibited the acid secretion induced by indomethacin. The results show that, PG $E_2$ derivatives, HK-3 and HK-4, inhibit acid secretion and also have protective effects on gastric ulceration induced by ethanol or aspirin.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.1057-1060
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• 2016

Background: The tumor suppressor p53 is as a regulator of cell proliferation, apoptosis and many other biological processes as well as external and internal stress responses. Mdm2 SNIP309 is a negative regulator of 53. Therefore, this study aimed to determine the role of the Mdm2 SNIP 309 polymorphism in the gastric mucosal morphological patterns in patients with Helicobacter pylori associated gastritis. Materials and Methods: A prospective cross-sectional study was carried out from November 2014 through November 2015. Biopsy specimens were obtained from patients and infection was proven by positive histology. Gastric mucosa specimens were sent to the Molecular Genetics Unit, Institute of Medicine, Suranaree University of Technology where they were tested by molecular methods to detect the patterns of Mdm2 SNIP 309 polymorphism using the real-time PCR hybridization probe method. The results were analyzed and correlated with gastric mucosal morphological patterns by using C-NBI endoscopy. Results: A total of 300 infected patients were enrolled and gastric mucosa specimens were collected. In this study the percentage of Mdm2 SNIP 309 T/T homozygous and Mdm2 SNIP309 G/T heterozygous was 78% and 19 % respectively whereas Mdm2 SNIP309 G/G homozygous was 3%. Mdm2 SNIP 309 T/T homozygous and Mdm2 SNIP309 G/T heterozygosity correlated with type 1 to type 3 gastric mucosal morphological patterns (P<0.01) whereas Mdm2 SNIP309 G/G homozygous correlated with type 4 and type 5 (P<0.01). Conclusions: Our study finds the frequency of Mdm2 SNIP309 G/G in a Thai population is very low, and suggests that this can explain ae Thailand enigma. Types 1 to type 3 are the most common gastric mucosal morphological patterns according to the unique genetic polymorphism of MDM2 SNIP 309 in the Thai population.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.15 no.1
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• pp.23-28
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• 2012

Purpose: Interest in peptic ulcer in children has been relatively low because the disease is rarer in children than in adults and there were restrictions in the application of endoscopy to children, but the recent development of pediatric endoscopy is activating research on pediatric peptic ulcer. Thus, this study compared the $H.$ $pylori$ infection rate and clinical and endoscopic findings among pediatric patients diagnosed with peptic ulcer. Methods: We analyzed retrospectively 58 pediatric patients for whom whether to be infected with $H.$ $pylori$ was confirmed selected out of pediatric patients diagnosed with gastric ulcer or duodenal ulcer through upper gastrointestinal endoscopy at the Department of Pediatrics of Gachon University Gil Hospital during the period from January 2002 to December 2007. A case was considered $H.$ $pylori$ positive if $H.$ $pylori$ was detected in the Giemsa stain of tissue or the results of UBT (urea breath test) and CLO (rapid urease test) were both positive. Results: Of the pediatric patients, 37 were infected with $H.$ $pylori$ and 21 were not. The $H.$ $pylori$ infection rate increased with aging and the result was statistically significant ($p$<0.05). However, $H.$ $pylori$ infection was not in a statistically significant correlation with sex, chief complaint, and gastroduodenal ulcer ($p$>0.05). Conclusion: $H.$ $pylori$ infection increased with aging, but was not significantly correlated with gastroduodenal ulcer. Further research may need to examine prospectively the relation between $H.$ $pylori$ and gastroduodenal ulcer in the Incheon area.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.2
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• pp.133-138
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• 2001

In this study, an attempt was made to increase the survival rate of bifidobacteria entrapped in alginate in the gastrointestinal tract, and to investigate the potential industrial applications, for example lyophilized capsules and yogurt. First, the protective effect of various food additives on bifidobacterial survivability was determined after exposure to simulated gastric juices and bile salts. The additives used in this study were skim milk (SM), polydextrose (PD), soy fiber (SF), yeast extract (YE), chitosan (CS), $\kappa$-carageenan ($\kappa$-C) and whey, which were added at 0.6% concentration (w/v) to 3% alginate-bifidobacterial solution. In the simulated gastric juices and bile salts, the protective effect of 0.6% skim milk-3% alginate (SM-A) beads on the survival rate of bifidobacteria proved to be higher than the other additives. Second, the hydrogen ion permeation was detected through SM-A vessel without bifidobacterial cells at different SM concentrations (0.2%, 0.4%, 0.6%, 0.8%, and 1.0%). There were no differences in terms of the pH decrease in SM-A vessels at 0.6%, 0.8%, and 1.0% (w/v) SM concentrations. The survival rate of bifidobacteria in SM-A beads would appear to be related to the SM buffering capacity against hydrogen ions and its tendency to reduce the pore size of bead. In this experiment, the survival rate of bifidobacteria entrapped in beads containing 0.6% SM showed the highest viability after exposure to simulated gastric juices for 3h, thereby indicating that 0.6% SM is the optimum concentration fir 3% alginate bead preparation. Third, the effect of SM-A beads on the freeze-drying and yogurt storage for 10 days was investigated. SM-A beads were found to be more efficient for freeze drying and yogurt storage than untrapped cells and the alginate bead. Consequently, the survival rate of bifidobacteria entrapped in SM-A beads was increased in simulated gastric juices, bile salts and probiotic products, such as lyophilized capsules and yogurt, SM-A beads can be expected to produce high value probiotic products.

• Economic and Environmental Geology
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• v.48 no.3
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• pp.199-204
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• 2015

In this study, we aimed to make antibiotic-intercalated smectite composites using amoxicillin and clarithromycin as hygroscopic antibiotics, and gentamicin, tobramycin and netilmicin as non-hygroscopic aminoglucosides, and to check their drug delivery potential in gastric system using preliminary in-situ column release test for clarithromycinsmectite composite. All antibiotics were successfully intercalated into the interlayer of smectite by cation-exchange reaction in the batch experiment. Equilibrium batch test showed that clarithromycin-intercalation followed Langmuir isotherm and the possible maximum amount was calculated as 1.811 mmole/g. Clarithromycin was continuously released by the solutions of pH=2, 3, and 4 and the amount was decreased with pH increase.

• The Korea Journal of Herbology
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• v.24 no.1
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• pp.41-47
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• 2009

Objectives : The objective of this study was to examine the effects of P. oleracea into the HCl-ethanol induced gastritis in rats, and to isolate and determine the chemical compounds from P. oleracea. Methods : The rats were orally administered with crude extract or fractions or isolated compounds of P. oleracea 30 mins before the induction of gastric lesion by oral administration of HCl-ethanol. The gastric lesional area was measured using pixel counting software. Then the chemical compounds from P. oleracea was isolated and determined by LC-MS and NMR. Results : The inhibition effect of oral administration of crude extract of P. oleracea at a dose of 500 mg/kg in HCl-ethanol induced gastritis was similar to cimetidine. Then, aqueous fraction at a dose of 240 mg/kg exhibited the effects similar to cimetidine. Then, the aqueous fraction was further separated by MPLC and yielded four sub fractions. Among those sub fractions, agent II at a dose of 40 mg/kg possessed the strongest effect in the HCl-ethanol induced gastritis. The water fraction yielded-Uridine, Adenosine, Guanosine, which were characterized by Mass, 1H-NMR, 13C-NMR. Conclusions : This study suggest that a P. oleracea and its compounds showed potent efficacy on the development of HCl-ethanol induced gastritis. Thus, P. olaracea can be a potential natural resource for the management of gastritis although the mechanism of action involved in the treatment remains to be explored.

• Biomolecules & Therapeutics
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• v.8 no.1
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• pp.38-43
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• 2000

Several studies have shown that the stomach has sufficient alcohol dehydrogenase (ADH) activity to metabolize some amount of orally administered alcohol and the sex-related differences in the first-pass metabolism of alcohol might be associated with differences in the activity of gastric ADH(GADH). The aim of this study was to asses the sex-related differences in GADH in 48 male and 48 female Sprague-Dawley rats aged 1, 4, 10, 15, 20, and 30 weeks which each aged group had same sex ratio. The GADH activity was determined spectrophotometrically at 37$^{\circ}C$. The formation of NADH was monitored at 340nm for 10 minutes in the 1 ml of reaction mixture (0.5 M of Tris-HCl, pH 7.2 + 1.5 M of ethanol + 2.8 mM of NAD + 30 $\mu$l gastric mucosal supernatant). The GADH activity (nM of NADH/min/mg of cytosolic protein) was calculated using molecular extinction coefficient of 6.22 $\textrm{cm}^2$/$\mu$M for NADH. The GADH activities were 2.94$\pm$0.82 (n=48) in female rats and 3.34$\pm$2.17 (n=48) in male rats and had not significant difference between sex. However, the GADH activities were significantly (p<0.01) higher in female (1.91$\pm$0.59 and 3.30$\pm$0.49) than in male (0.68$\pm$0.43 and 1.92$\pm$0.81) of 1 and 4 weeks rats. However, it was significantly (p<0.05) higher in male (6.48$\pm$1.81, 3.65$\pm$1.04 and 5.13$\pm$1.30) than in female (4.23$\pm$1.23, 2.18$\pm$0.77 and 2.56$\pm$0.93) of 10, 20 and 30 weeks rats, respectively. Therefore, the results suggested that sex-related differences of the GADH activities in same aged rats were existed by age.

• Natural Product Sciences
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• v.12 no.3
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• pp.150-152
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• 2006

The ethanol extract of Sida acuta Burm. (ALSA) whole plant was studied for its anti-ulcer activity against aspirin plus pylorous ligation induced gastric ulcer, HCl-ethanol induced ulcer, and water immersion stress induced ulcer (WISIU) in rats. We found that ALSA at a dose of 300 mg/kg, (orally) markedly decrease the incidence of ulcers in the first two models. ALSA showed reduction in gastric volume, free acidity, and ulcer index (53.69%). It has not reduced the total acidity significantly and no significant change in pH. It also showed 55.14% gastro protective activity, wheres standard drug sucralfate showed 94.85%. WISIU showed protection index 24.4%, whereas standard drug omeprazole (OMEZ) showed protection index 100%.

• The Korean Journal of Food And Nutrition
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• v.15 no.1
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• pp.16-22
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• 2002

The effects of nitrite scavenging. electron donating and N-nitrosodimethylamine(NDMA) formation in vitro arid green tea(Camellia sinensis) and Maesil(Prunus mume) were studied. The green tea and Maesil extracts were tested for their nitrite-scavenging effect under the different pH conditions such as pH 1.2, 4.2 aud 6.0. The effects of nitrite-scavenging in all concentrations were diminished in the alkali condition, while its effects in the acidic condition of pH 1.2 were reached of more than 99.0% by adding above 0.5ml of green tea extract. And also, nitrite-scavenging effect by adding 3ml of Maesil extract was about 77.0%. The electron donating ability(EDA) of green tea and Maesil extracts was 70.6%, 75.1%, respectively. The formation of NDMA was very effectiveness which was inhibited 82.1%, 73.2% at reaction mixture of pH 2.5 adding 3ml of above extracts. respectively . The ground CW. TW1 and TW2 (refer to Table 1) diets were incubated with 10m1 simulated saliva and 40m1 gastric juice at 37$^{\circ}C$ for 2hrs. NDMA formation was inhibited at all levels of green tea and Measil extracts.