Objective To study the role of gastric mitochondrial DNA cytochrome C oxidases (COX) subunit Ⅱ gene and its expression in diabetic gastric motility dysfunction. Methods Seventy Wister rats were randomly divided into 2 groups: diabetic group (STZ 60mg/Kg intraperitonealy) and control group. The changes in expressions of COX protein were assayed by Westernblot. Mitochondrial DNA COX mRNA was assayed with reverse-transcriptional polymerase chain reaction(RT-PCR). Cytochrome C oxidase activity was determined by ultraviolet spectrophotometer. Results Gastricelectric dysrythmia was more frequently delected in diabetic rats, and the COX activity in diabetic rats was 0.41?0.21/min, which was significantly lower than that in normal rats (0.78?0.37/min). The expression of gastrointestinal COX protein and COX gene in diabetic gastroparesis rats were markedly decreased compared with normal rats. Conclusion Cytochrome C oxidases activity was greatly reduced in diabetic rats. Diabetic gastroparesis was associated with down-regulation of the expression of gastrointestinal mtDNA encoding COX gene and protein. These changes might play a key role in pathogenesis of diabetic gastroparesis

Objective To investigate the relationship between mitochondrial membrane potential change and apoptosis of smooth muscle cells of the small intestine in diabetic rats. Methods Seventy Wistar rats were randomly divided into two groups: diabetic group(STZ60mg/kg intraperitonealy) and control group.The gastric empty time and intestinal transit were determined in diabetic rats 2 months after the reproduction of diabetes. Mitochondrial membrane potential in small intestinal smooth muscle cells was determined by the change in the intensity of labeling rhodamine 123 with lasor scanning confocal micrographs, and apoptosis index was assessed with the technique of terminal deoxynucleotidyl transferase mediated d-UTP nick end labeling(TUNEL) test and flow cytometry.The changes in expression of cytochrome C were determined by Western blotting. Results The mitochondrial membrane potential of small intestine smooth musele cells was significantly lowered in diabetic rats compared with normal rats. Apoptosis index in diabetic rats was significantly higher than that of normal as shown by TUNEL technic. Apoptosis rate in diabetic rats was 15%, and it was significantly higher than that of normal rat (P

Objective To study the change in cytosolic Ca 2+ in smooth muscle cells in gastric antrum of diabetic rat. Methods Rats were randomly divided into diabetic group and control group. Gastric empty time was determined 3 months after diabetes was reproduced in rats, the apoptosis rate of smooth muscle cells in the gastric antrum was assessed by flow cytometry, and the content of cytosolic Ca 2+ in smooth muscle cells was measured by laser scanning confocal microscopy. Results In diabetic rats, gastric emptying was significantly delayed. Compared the normal rats, the content of cytosolic Ca 2+ in smooth muscle cells from the antrum of diabetic rats was increased. The apoptosis rate of smooth muscle cells in the antrum of diabetic rats was 15%, and it was higher than that in normal rats. Conclusion With the increase in the content of cytosolic Ca 2+ in smooth muscle cells, smooth muscles were damaged and therefore their contraction was also impaired.

Objective To study the role of nitriergic nerves in the myenteric plexus of the gastric antrum in diabetic rats with motor disorder. Methods Rats were randomly divided into diabetic group and control group. Electrogastrogram was recorded, and the number of cholinergic nerves in the myenteric plexus of the gastric antrum was counted 3 months after reproducing diabetes in the model group. Results In the rats of diabetic group, gastro-electric dysrhythmia was observed more frequently, and the number of nitriergic cells in the myenteric nerves was significantly decreased compared with control group. Conclusion The changes in nitriergic nerves in the myenteric plexus of the gastric antrum might be one of the mechanisms of gastro-electric dysrhythmia and gastric motility disorders in diabetic rats.

Objective To analyze and investigate endoscopic and pathological characteristics in the diagnosis of early esophageal carcinoma. Methods The clinical data of 62 patients with early esophageal carcinoma who had been admitted to Southwest Hospital from January 2003 to December 2007 were retrospectively analyzed. Results Of all patients, 8 had upper esophageal carcinoma, 42 had middle esophageal carcinoma and 12 had lower esophageal carcinoma. The tumor growth patterns included surface diffusion growth (n = 30), bidirectional growth (n = 11), intracavitary growth (n = 9), intra-esophageal wall growth (n = 7) and mixed growth (n = 5). The diameter of lesions ranged from 1.0 cm to 2.9 cm in majority. Surgical resection was done in 38 patients, endoscopic mucosal resection in 23 patients and endoscopic submucosal dissection in 1 patient. Postoperative pathological examination showed that 13 patients had in situ carcinoma, 22 had intramucosal carcinoma and 27 had submucosal carcinoma. The lymph node metastatic rate of intramucosal carcinoma and submucosal carcinoma were 5% (1/22) and 15% (4/27), respectively. The numbers of squamous cell carcinoma, adenocarcinoma, small cell carcinoma, sarcoma carcinoma and spindle carcinoma were 57, 2, 1, 1, 1, respectively. ConelusionsEarly esophageal carcinoma tends to appear in the middle part of esophagus, and with surface diffusion growth type. Most of the early esophageal carcinoma are squamous cell carcinoma. Endoscopy combined with lugol's iodine and methyleneblue staining is effective in detecting early esophageal carcinoma.

Objective To study the effect of carbachol(CCH) on membrane potential of smooth muscle cells of gastric antrum of diabetic rats to verify the mechanism of gastric motility disturbance.Methods Fifty healthy Wistar rats of 2-month old,weighing 100-160 g,were divided into the control group(n=20) and diabetes mellitus group(n=30).Three months after the establishment of the rat model of diabetes by intraperitoneal injection of 60 mg/kg streptozotocin,gastric emptying time and gastric electrical activity were measured,and the resting membrane potentials of smooth muscle cells in antrum were measured by confocal laser scanning microscopy,then treated with carbachol of 10~(-9) mmol/L,10~(-8) mmol/L,10~(-7) mmol/L,the membrane potentials were measured.Results As compared with the normal rats,gastric emptying time in diabetic rats was significantly longer and abnormal gastric electric rhythm was significantly increased,the abnormal rhythm index(ARI) and the coefficient of variation(CV) of slow wave frequency in diabetic rats were significantly higher,but the resting membrane potentials remained unchanged and the sensitivity of CCH-induced membrane depolarization was increased.Conclusion The increase of sensitivity of CCH-induced membrane depolarization may be involved in the diabetes-induced gastric motor disorders.

Objective To clarify the changes of ultrastructure of interstitial cells of Cajal in the small intestine of diabetic rats. Methods Rats were randomly divided into diabetic group and control group. The rate of the small intestinal transit was measured and the tissues of the small intestine were observed by transmission electron microscopy at 3 months after the establishment of rat model of diabetics. Results In the diabetic rats, the rate of small intestinal transit was delayed as compared with that in the control group. The number of the gap junction of interstitial cells of Cajal in the small intestine of diabetic rats decreased significantly, and the rest structures were damaged. Damaged organelles and formation of vacuoles were also found. Conclusion The changes of ultrastructure of interstitial cells of Cajal in the small intestine may be one of the mechanisms resulting in slow rate of the small intestinal transit in diabetic rats.

Objective To evaluate the differences, including clinical symptoms, endoscopic and histopathologic findings, status of Helicobacter pylori (Hp) infection and cytokeratin (CK) expressions, be-tween Barrett esophagus (BE) and heterotopic gastric mucosa (HGM) in upper esophagus. Methods Clinical data of 152 patients with BE and 52 patients with HGM in upper esophagus diagnosed from February 2004 to September 2005 were retrospectively studied. The parameters being compared include-ed clinical manifestations, conventional and magnifying endoscopic findings, histopathological findings, Hp infection determined by rapid urease test and Warthin-Starry staining and expression of CK phenotypes detec-ted by immunohistochemistry. Results Gastro-esophngeal reflux was observed in 64. 5% of patients with BE (98/152), higher than that in patients with HGM ( 13.5%, 7/52, χ2 = 40. 36, P < 0. 01 ). Endoscopic faveolus of BE mucosa included 46 cases of spot pattern, 65 striations and 41 villiform patterns, while those of HGM were all striation patterns. The histologic classification in BE included 56 cases of fundic type, 39 junction type and 57 specialized intestinal metaplasia, while in HGM mucesa, 31 cases of fundic type, 16 junction type and 5 antrum type were diagnosed, and no goblet cells were found. Moderate and severe infil-tration of inflammatory cells in BE mucosa was 63.2% (96/152), which was significantly higher than that in HGM mucosa (15/52, 28. 8%, P<0. 01). However, no difference was found in gastric antrum inflam-mation between the two groups (44.7%, 68/152, vs. 51.9%, 27/52, P>0.05). No difference was ob-served in prevalence of Hp infection between BE and HGM groups (P >0. 05 ), either in involved mucosa or in antrum. CK7 was not expressed in HGM or normal squamons mucosa, but was expressed in BE. CK20 and CK19 were expressed in both HGM and BE, and CK13 expression was found in some BE nmcosa including gas-tric metaplesia (55/95) and intestinal metaplasia (29/57) but not in HGM mucosa. Conclusion There are differences between HGM and BE, in regarding of reflux symptoms, magnifying endoscopic findings, histo-logical types and CKs expressions, which may be indicators to make differential diagnosis.

Objective To assess the potential diagnostic value of the potential of flexible image col-or enhancement system(FICE)with magnifying endoscopy for superficial esophageal lesions by observing the intrapapillary capillary loops(IPCL)in esophageal mucosa. Methods IPCL in patients with esophageal diseases were studied with Fujinon EG-590ZW FICE endoscopy. The relationship between changes of IPCL in 31 cases of superficial esophageal lesions and pathological findings was studied. Results The vascular patterns of IPCL were analyzed and classified as follows: Type Ⅰ,often seen in normal esophagus,were e- venly distributed with regular forms. TypeⅡ,protracted,often occured in esophagitis. Type Ⅲ showed two or three of such four changes as,dilatation,wave-like inflection,irregular caliber and deformity,which was mainly seen in dysplasia. While Type Ⅳshowed all the four changes mentioned above and frequently ap- peared in esophageal cancer. Of the 17 cases of esophagitis,fifteen cases were TypeⅡIPCL and the others Type Ⅲ. Of the 10 cases of dysplasia,eight were Type Ⅲ IPCL and two high-grade dysplasia showed Type Ⅳ IPCL. One sml early esophageal cancer showed Type Ⅲ IPCL and all three advanced esophageal cancer showed TypeⅣ IPCL. Conclusion The esophageal microvessels can be clearly seen by FICE with magnif- ying endoscopy,and the differentiation of superficial esophageal lesions can be fairly performed with the ob- servation of IPCL,it gives an important practical siginificance in diagnosing tumorous lesions.

Objective To investigate the endoscopic and ultrasonic endoscopic features of colorectal carcinoid and the indications of endoscopic treatment. Methods The clinical data of 22 patients with colorectal carcinoid who had been admitted to our hospital from 2002 to 2007 were collected. The endoscopic and ultrasonic endoscopic features and the relationship between the features and invasion depth of colorectal carcinoid were analyzed. Results Under the endoscope, early carcinoid presented submucosa tumor with 1.5cm in diameter, and yellow or white smooth surface; advanced carcinoid presented submucosa tumor with 0.8-3.0cm in diameter, and yellow or white little nodus or ulcerative surface. The ultrasonic endoscopic feature of the colorectal carcinoid was orbicular-ovate low level echo tumor with punctiform slightly high-level echo and an unsharpness edge. Sixteen mucosal layer-cancers and submucosal layer-cancers were removed by endoscopic mucosal resection, and 10 of them were additional treated by argon plasma coagulation. After a follow-up period of 4-36 months, no recurrence was observed. Conclusions Endoscopy and endoscopic ultrasonography are effective methods to diagnose colorectal carcinoid and its invasion depth. Endoscopic treatment is a simple, safe and effective means to treat the early colorectal carcinoid tumors.