In recent years, gastrointestinal pace-maker or electrical stimulation has been proposed as a therapeutic option. The interstitial cells of Cajal (ICC) are the pacemaker cells in the gastrointestinal tract.They have special properties that make them unique in their ability to generate and propagate slow waves in gastrointestinal muscles which determine the frequency, the direction and velocity of the propagation of peristaltic activity, in concert with the enteric nervous system for GI motility. Gastrointestinal pacing has been used in the treatment of gastroparesis syndrome, morbid obesity, irritable bowel syndrome, functional dyspepsia and gastroesophageal reflux disease. To better understand the gastrointestinal pacing, a review of its effects and mechanism is presented in this series of papers.

Gastric cancer is a result of interaction of multiple factors. In previous studies it was found that genetic instability, abnormality of DNA methylation, telomere loss, mismatch of repair gene and k-ras mutation, loss of heterozygosity (LOH) of some of cancer-inhibitory genes such as APC, MCC and DCC, disbalance between cell proliferation and apoptosis, etc. were associated with the development of gastric cancer. It was also discovered that tretinoin, sodium selenite, sodium butyrate and epigallocatechin-3-gallate (EGCG) may be effective in preventing gastric carcinoma and gene therapy may partially reverse the malignant phenotype of gastric cancer cells.

Helicobacter pylori ( H.pylori )infection is an important aetiological risk factor of gastric cancer, and has been classified as group I or definite carcinogen by the World Health Organization. The molecular mechanism of H.pylori leading to gastric cancer is still unclear. It has been increasingly recognized that cell proliferation and appoptosis,telomerase activition, genetic instability and abnormal DNA methylation are involved in the development of H.pylori related gastric cancer and its precursors. To better understand the pathogenesis of gastric cancer, a revie of the role of H.pylori infections in the induction of molecular events in gastric epithelial cells is presented in this paper.

0 05). Conclusion mtMSI may be involved in the carcinogenesis of some hepatocellular carcinomas, but mtMSI is not associated with nMSI.

Quantitative DNA measurements were done in mitotic figures in cells from early gastric carcinoma of intestinal type(n = 8), slight (n=10), moderate (n=10) and severe dysplasia (n = 8), and simple intestinal metaplasia (n=10). The mean DNA values were found to increase gradually from intestinal metaplasia to early gastric carcinoma, with the sequence of from slight, moderate to severe dysplasia, and the differences between each two adjacent groups being statistically signi ficant (P

The expression of tumor-associated glycoprotein (TAG-72) identified by monoclonal antibody B72.3 was investigated in HO resected specimens of gastric carcinoma,36 biopsied specimens of dysplasia,and 303 specimens of intestinal metaplasia(IM).IM was subdivided into complete Type I and incomplete Types Ⅱ and Ⅲ based on whether sulphomucin is present or absent in the mucin secreting columnar cells.The positive rate of TAG-72 in gastric carcinoma was 60.9%,and it was significantly higher in IM specimens with gastric carcinoma than in those with benign gastric lesions (P

Objective To investigate the effect of membrane-cytoskelet on linker Ezrin in the invasion and migration of human adenocarcinoma cells line AGS. Methods Two small hair RNA targeting Villin2 gene ( Ezrin coding gene) was designed,chemically synthesized and inserted into plasmid pGenesil-shRNA,then transformed into E. coli DH5 ?. The recombinant plasmid was extracted in middle quantity and transfected into AGS cells by LipofectamineTM 2000. Ezrin expression in AGS cells transfected by shRNA recombinant plasmid was measured by RT-PCR and Western blotting. AGS cells were transfected by effective shRNA plasmid and cultured in 1640 media containing G418 ( 800 ?g/ml) . RT-PCR and Western blotting were applied respectively to detect the Ezrin mRNA and protein expression to evaluate the blocking effect of shRNA-Ezrin. Cell migration and invasion was determined by scratch test and Transwell chamber assay. Results Our designed shRNA knocked down 93% Ezrin in AGS cells which had a stable expression of Ezrin small hairpin RNAs. The migrated cells number of Ezrin knocked-down group was 27. 67 ? 4. 50,which was significantly decreased compared with the control group ( 125. 50 ? 8. 33,P

Objective To study of relationship of the mRNA expression of protection of telomeres 1(POT1) and the activity of telomerase with the incidence of gastric carcinoma.Methods Lesioned gastric mucosal tissues and the corresponding normal tissues from 30 cases of gastric cancer,30 cases of moderate or severe atypical hyperplasia,and 30 cases of intestinal metaplasia were collected in this study.The expression of POT1 mRNA was detected with real time-PCR and the activity of telomerase was examed with TRAP-ELISA.Results Real time-PCR analysis showed that POT1 expression was increased in the gastric carcinoma tissues compared with the paracancerous normal mucosal tissues,increased in the severe atypical hyperplasia than in the corresponding normal tissues,but there was no difference between intestinal metaplasia tissues and normal tissues.The activity of telomerase in the advanced gastric tumors and severe atypical hyperplasia was significantly higher than that in intestinal metaplasia tissues and normal gastric mucosal tissues.However no obvious difference was found in the activity in gastric tumors and severe atypical hyperplasia with intestinal metaplasia tissues and normal gastric mucosal tissues.Conclusion Although the activity of telomerase in gastric cancer and severe atypical hyperplasia is significantly higher than that in normal and intestinal metaplasia tissues,POT1 mRNA has no relationship with this change.

Objective To study the effects of ?-tocopheryl succinate (?-TOS) on apoptosis of gastric cancer cells induced by TRAIL. Methods The cell cycles and the percentage of apoptosis were analyzed with flow cytometer and the expressions of NF-?B, survivin, bcl-2 and caspase-3 in gastric cancer cells were assessed with Western blot. Results After being exposed to TRAIL 300ng/ml for 24 hours, the apoptosis rate was 36.05% for MKN28 and 11.80% for SGC-7901. When exposed to ?-TOS at 60?mol/L for 24 hours, the apoptosis rate was 9.0% for MKN28 and 8.5% for SGC-7901. With a combination of ?-TOS 60?mol/L and TRAIL 300ng/ml for 24 hours, the apoptosis rate was elevated to 48.1% for SGC-7901 and 63.7% in MKN28, respectively. The results of Western blot showed that TRAIL inhibited the expressions of NF-?B and survivin, while had no inhibition on the expressions of bcl-2 of SGC-7901 and MKN28 cell lines. The expression levels of bcl-2 and survivin had no change when the cells were exposed to ?-TOS alone. When the cells were treated with ?-TOS and TRAIL simultaneously, the expressions of NF-?B, bcl-2, and survivin were greatly decreased. Conclusions ?-TOS can enhance the activity of TRAIL in inducing apoptosis, and the down-regulation of the expression of NF-?B, bcl-2 and survivin may be involved in the mechanisms.

Objective To study the effects of concentrated H.pylori culture supernatant(CHCS) on the expressions of COXⅠ mRNA and protein in gastric carcinoma cells,and explore the potential role of H.pylori in the gastric carcinogenesis.Methods After SGC7901 cells were treated by 6 ?l/ml CHCS for 4 h,8 h,12 h respectively,the expression of COXⅠmRNA and protein was detected by RT-PCR and Western blotting.Results The expression of COXⅠmRNA decreased gradually after exposure to CHCS for 4 h.Especially after 8 h,the expression decreased significantly.When treated with CHCS for 12 h,the expression continued to decrease(P