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The pooling method aggregates the points in the neighborhood in Convolutional Neural Network(CNN). It can not only reduce the dimension, but also improve the results, so that the results are not easy to over-fit. However, the common pooling methods have the problems of single feature and lack of self-adaptability. In order to solve this problem, the Pulse Coupled Neural Network (PCNN) is introduced and a pooling method based on PCNN is proposed. The algorithm learns the weights of each eigenvalue from the convoluted neighborhood sub-region by PCNN and fuses them to get the final pooling result. The experimental results on image recognition datasets MNIST, CIFAR-100 show that the proposed PCNN-based pooling method has better recognition effect and improves the performance of CNN compared with the existing pooling methods.

Based on the non-linear equivalent spring-damper model in the "two-state model", Impact model with hinge clearance for deployable mechanism of folding wing is set up and deploying dynamics on deployable mechanism of folding wing is simulated including impact force variation caused by the size of clearance and the clearance friction by using ADAMS software. The results show that the random continuous impact force is produced by the influence of clearance; as dimensions of the clearance increase, impact times decrease and amplitudes of impact forces are increased; System energy consumption is speeded up and to some extent times of impacts with clearance and disturbance effects of deployable mechanism is suppressed by friction in the whole deployable process.

The role of esophageal hypersensitivity in functional heartburn (FH) with negative pH test, negative symptom index, and the proton pump inhibitor (PPI) failure has not been established. The aim of this study was to investigate the characterization of visceral hyperalgesia evoked by esophageal balloon distention and acid perfusion in patients with FH, nonerosive reflux disease, and erosive esophagitis and further characterize the pathophysiologic mechanism of FH.A total of 21 FH patients (with esophageal acid exposure3.1% and a symptom index50% and nonresponse to a therapeutic trial with proton pump inhibitors, 25 Nonerosive reflux disease (NERD) patients (with esophageal acid exposure4%), 23 erosive esophagitis (EE) patients (LA grade B to D), and 18 healthy controls were recruited in the study. Mechanosensitivity including the initial perception threshold (IPT) and pain threshold (PT) was evaluated by using a Barostat with a double-random staircase distension protocol. Chemosensitivity was graded along a visual analog scale after perfusion of saline and 0.1 N HCl.The baseline IPTs and PTs were all lower in patients with FH, NERD, and EE than in the controls (all P0.01). In addition, the baseline PT in FH patients was significantly lower than those in NERD (P=0.015) and EE patients (P0.001). After acid perfusion, the mean symptom intensity scores were significantly greater in patients with FH, NERD, and EE than those in the controls (all P0.001). The postacid perfusion IPTs in patients with FH, NERD, and EE were all significantly lower than the corresponding baseline values (all P0.01). The PTs in FH (P=0.026) and EE patients (P0.001) were significantly lower than the corresponding baseline values. Moreover, the postacid perfusion PT was significantly lower in FH patients than in NERD patients (P0.001).FH patients are more sensitive to mechanical or chemical stimuli than NERD patients. Sensitization of esophageal acid-sensitive chemoreceptors may exert a significant influence on the pressure-sensitive mechanoreceptors, and there is the cooperative interaction in the process of esophageal visceral hyperalgesia.

A novel method for preparation of alkali-activated metakaolin/granulated blast furnace slag (GBFS)-based geopolymer reinforced by organic resins (OR) was reported. The geopolymer composites by doping an amount of 1 wt% OR displayed the highest compressive and flexural strengths at the different curing times. The calorimetry results showed that the reaction heats of the geopolymer composites at the early reaction stage of 1~3d are much higher than that of geopolymer due to the geopolymerization rate to be accelerated by incorporation of OR. A reasonable reinforced mechanism was proposed.

BACKGROUND Patients with sliding hiatus hernia (HH) and reflux esophagitis (RE) usually suffer from esophageal dysmotility. The aim of the present study was to investigate the role of acid reflux and duodenal gastroesophageal reflux (DGER), esophageal manometry, and esophageal dysmotility by applying the barium meal examination. METHODS RE with HH was initially diagnosed using the reflux disease questionnaire, and was further confirmed by a barium meal examination and an endoscopy. The radiographic technique was used to test for spasms, strictures, and the coarseness of the mucosa, also was to study the types of reflux and clearance. Then, the esophageal manometry, the esophageal 24-hour pH, and the bilirubin monitoring were observed. RESULTS Fifty-five patients were diagnosed as HH combined with RE and divided into two groups according to the severity of their esophagitis: group HH1 (grades A and B) and group HH2 (grades C and D). The barium meal examination revealed that the mucosa was either granular or nodular in all cases. The dump reflux and delayed clearance were more significant in patients in the HH2 group than those in the HH1 group (P < 0.05). The percentages of total, supine, and upright acid exposure time were greater in patients with HH than those in the control group (P < 0.01), but the differences between the HH1 and the HH2 groups were not significant. Lower esophageal sphincter pressure (LESP) was lower in the HH group than in the control group (P < 0.05). Three DGER parameters: the percentage of time with absorbance greater than 0.14, the number of bile reflux episodes, the number of bile refluxes lasting longer than 5 minutes were (28.43 +/- 23.34), (40.57 +/- 31.30), and (15.15 +/- 8.72), respectively in the HH2 group; these statistics were significantly higher than those for the HH1 (P < 0.05). The frequency and amplitude of peristalsis were all lower in HH patients than in the control (P < 0.05). Of all the patients, 54.3% (30 of 55) with acid reflux and DGER simultaneously in the HH group exhibited refluxes of barium from the stomach to the esophagus in the recumbent position, and 29.4% (5 in 17) with delayed clearance in the HH group were correlated with esophageal body peristalses. The result was that the frequency and amplitude of peristalsis were less and the duration of esophageal peristalsis was longer than those of control group. CONCLUSIONS Esophageal dysmotility may play an important role in the severity of RE combined with HH. Esophageal motility results on a barium examination may coincide with esophageal manometry, 24-hour pH, and bilirubin monitoring in the RE and HH, but the radiologic method was the simplest to apply.

Esomeprazole is the S-isomer of omeprazole, with a stronger acid suppressive effect than omeprazole. This open, randomized crossover study was designed to evaluate the effect of esomeprazole and another proton-pump inhibitor, rabeprazole, on intragastric pH in healthy Chinese.Thirty-six healthy volunteers (26 men and 10 women, aged between 20 and 31 years) were enrolled. Subjects were given either esomeprazole 40 mg (n = 18) or rabeprazole 10 mg (n = 18) orally once daily for 5 days during the first dosing period, then the other medicine at the set dosage for the second dosing period. The two periods were separated by a 14-day washout phase. The doses were chosen according to the State Food and Drug Administration of China for the treatment of acid-related diseases. Intragastric pH was continuously monitored for 24 h on days 1 and 5 of each dosing period. CYP2C19 genotypes were analyzed to identify the extensive metabolizers (EM) and poor metabolizers (PM).The percentage of time with intragastric pH4 was significantly higher (P0.001) in subjects receiving esomeprazole than in those receiving rabeprazole in the first 4 h after administration of the first dose (70.65% vs 44.87%), at 24 h on day 1 (73.7% vs 54.8%) and at 24 h on day 5 (84.2% vs 76.2%). The median intragastric pH was also higher in subjects receiving esomeprazole than in those receiving rabeprazole in the first 6 h, day 1 and day 5 (Por= 0.001). The percentage of subjects with intragastric pH4 for at least 16 h on day 1 (63.9% vs 33.3%) and on day 5 (88.9% vs 61.1%) was higher after administration of esomeprazole than after rabeprazole (both P0.05). On genotype analysis, 28 of the subjects were EM and eight were PM. Those who were PM tended to have a higher, albeit not statistically significant, percentage of time with intragastric pH4 and the median 24-h intragastric pH than those who were EM. Both drugs were well tolerated.Esomeprazole 40 mg orally once daily is more effective and faster in increasing intragastric pH than rabeprazole 10 mg orally once daily, and thus offers a potential for improved efficacy in acid-related diseases.

It's the first time that interstation method for Rayleigh wave is used to study the 3-D VS structure in the crust and upper mantle beneath western China and its adjacent area. More than 3000 interstation great circle paths were processed to determine the phase velocity of the fundamental mode of Rayleigh wave, and finally 110 paths of high quality dispersion data were selected which show good spatial coverage in western China and its neighboring regions. Phase velocity maps from 15 s to 120 s were obtained by Tarantola's probability method. The shear wave velocity structure in the crust and upper mantle on 2° × 2° grid points in our studied area was inverted by Tarantola's least square method for nonlinear problem. Based on the physical property that the phase velocity of fundamental Rayleigh wave at period T is most sensitive to the VS structure around λ/3 depth, we provided a layer-velocity self-adaptive technique in the structure inversion, which can well accelerate converging speed and improve stability in the inversion. The main conclusions concerning the VS structure of the researched area are: (1) The western Qinghai-Tibet Plateau shows very high VS value in the lower-crust and top of the upper mantle, and the asthenosphere is not developed. But the eastern margin of the Qinghai-Tibet Plateau clearly shows low-velocity anomaly in the lower crust and top of the upper mantle, which probably created a southward extrusion channel for the low velocity crust material of the Qinghai-Tibet Plateau along the eastern margin of the plateau through the western Sichuan and Yunnan region and then linking the low velocity zone in northern Burma. In the northeastern margin of the Qinghai-Tibet Plateau, the VS of the lower crust is apparently lower than that of the mid-crust. (2) The Lhasa block of the southern Qinghai-Tibet Plateau has a high velocity lid in the upper mantle and from south to north the depth of the asthenosphere decreases from 130 km to 100 km, the thickness of the underlying asthenosphere increases from about 40 km to 80 km. The Qiangtang block of the northern Tibet shows lower velocity in lower crust, lacks high velocity lid in the upper mantle and displays much thicker asthenosphere. (3) The Tarim basin and Junggar basin both show high velocity structure in the upper mantle, asthenosphere layer does not clearly appear. Thickness and velocity of the lower crust in the Junggar basin is apparently higher than that in the Tarim basin. (4) Velocity in the lower crust and uppermost mantle beneath the western Mongolia plateau is apparently lower than its eastern part. In the middle-western Mongolia plateau a thick and large scale asthenosphere is clearly shown. This thick asthenosphere gradually becomes thinner from middle to eastern Mongolia plateau and above which the higher velocity lid becomes thicker and thicker. Geological explanations are accomplished based on results of inversion.

Oesophageal visceral hypersensitivity is thought to be important in generating symptoms in functional heartburn (FH). However, the neurophysiological mechanisms involved are poorly understood. The aim of this study was to compare the characteristics of oesophageal cortical evoked potentials (CEPs) induced by balloon distension and acid perfusion in FH and controls. We studied 21 FH patients and 12 healthy volunteers. Oesophageal mechanical stimulation was performed using the specially constructed mechanical pump. CEPs were recorded using the 10-20 international system of electroencephalogram recording. Oesophageal distention elicited recognizable, reproducible and muti-peak CEPs. CEP latencies for N1, P1 and N2 components were significantly shorter (P = 0.016, P = 0.003 and P = 0.031, respectively) in FH than in controls before perfusion. Acid perfusion significantly decreased the latencies of N1, P1 and N2 (P = 0.022, P = 0.007 and P = 0.041, respectively) and significantly increased the amplitude of P1-N2 components (P = 0.020) in FH patients, but not in controls. In conclusion, cortical evoked potential responses evoked by oesophageal distention and acid perfusion were greater in FH than in controls, suggesting that dysfunction of visceral neural pathways and/or alterations in cortical processing may produce and mediate oesophageal hypersensitivity in FH. These findings provide the evidence that central sensitization contributes to the development and maintenance of oesophageal hypersensitivity.

BACKGROUND AND AIM: Patients with gastroesophageal reflux disease (GERD) usually suffer from acid reflux and duo-denogastroesophageal reflux (DGER) simultaneously. The question of whether DGER has an important effect on the development of GERD remains controversial. The aim of the present study was to investigate the role of DGER in the pathogenesis of GERD and its value for the diagnosis of nonerosive reflux disease (NERD).METHODS: GERD was initially diagnosed using the reflux disease questionnaire. For further diagnosis, results of the upper gastrointestinal endoscopy (excluding a diagnosis of Barrett’s esophagus) were considered in conjunction with simultaneous 24 h esophageal pH and bilirubin monitoring.RESULTS: According to endoscopic findings, 95 patients (43 men, 50±10 years of age) were divided into two groups: the reflux esophagitis (RE) group (n=51) and the NERD group (n=44). Three DGER parameters, the percentage of time with absorbance greater than 0.14, the total number of reflux episodes and the number of bile reflux episodes lasting longer than 5 min, were evaluated in the study. For the RE group, the values of the DGER parameters (19.05%±23.44%, 30.56±34.04 and 5.90±6.37, respectively) were significantly higher than those of the NERD group (7.26%±11.08%, 15.68±20.92 and 2.59±3.57, respectively, PCONCLUSIONS: DGER may occur independently but plays an important role in the development of RE and GERD symptoms. Simultaneous 24 h esophageal pH and bilirubin monitoring is superior to simple pH monitoring in helping identify patients at risk for NERD.

To investigate in rats the role of endothelin (ET)-1 gene expression in the development and progression of acute gastric mucosal lesions (AGML) induced by stress, and the effect of BQ-123 (a special ETA receptor antagonist) on the AGML.A rat model of gastric ulcer induced by cold-restraint-stress (CRS) was used. ET-1 concentrations in the plasma and gastric mucosa were determined by radioimmunoassay (RIA), gastric mucosa blood flow (GMBF) was measured with a laser Doppler flow meter, the ulcer index (UI) was used to estimate the degree of gastric mucosa damage and the expression levels of ET-1 mRNA in the gastric mucosa were measured using dot blot and reverse transcription polymerase chain reaction (RT-PCR). Different doses of BQ-123 were administered via the left femoral vein prior to the stress in order to observe the effects of BQ-123 on the ET-1 concentrations in the plasma and gastric mucosa, the GMBF and the UI.Compared with the normal controls, the ET-1 concentrations in the plasma and gastric mucosa of the stressed rats were increased significantly (P0.05), the GMBF was decreased markedly (P0.01), and the UI increased dramatically (P0.01). There was a significant positive correlation between the gastric mucosal EF-1 concentration and the UI (r = 0.98, P0.01), and a significant negative correlation between the gastric mucosal ET-1 concentration and GMBF (r = -0.89, P0.01) and also between the UI and GMBF (r = -0.98, P0.01). The expression level of ET-1 mRNA in the gastric mucosa of the stressed rats increased significantly compared with that of the normal controls (P0.01), and there was a positive correlation between the expression of ET-1 mRNA and the ET-1 concentration in the gastric mucosa (r = 0.93, P0.01). Compared with the untreated animals, the GMBF was increased (P0.01) and the UI decreased significantly (P0.01) in the BQ-123-treated rats, and the dose of BQ-123 correlated with the degree of change in the GMBF and UI; however, the ET-1 concentrations of either the plasma or the gastric mucosa did not change markedly in the BQ-123-treated animals (P0.05).The present study showed that the level of expression of ET-1 mRNA and the synthesis of ET-1 in the gastric mucosa both increased significantly, which suggests that the increased concentration of endogenous ET-1 may be involved in the development and progression of stress ulcer (acute gastric mucosa lesion). The mechanism of action may be associated with a reduction of GMBF induced by ETAR-mediated vasoconstriction. BQ-123 can dose-dependently attenuate significantly the degree of damage to the gastric mucosa induced by stress, and may have therapeutic benefits for stress ulcer.

OBJECTIVE: The failure of dysmotility to explain the symptoms of pain in irritable bowel syndrome (IBS) led to studies on visceral hypersensitivity. Mucosal mast cells (MC) may be one factor influencing the response of visceral afferents to mechanical and chemical stimuli because they are found in close proximity to gastrointestinal mucosal sensory nerve terminals containing neuropeptides and a bi-directional pathway linking the central nervous system, gut and MC has been demonstrated. METHODS: The present study investigated the extent of MC and the neuropeptides, substance P (SP) and vasoactive intestinal peptide (VIP), in the intestinal mucosa of patients with IBS, as well as the location of the MC. The MC and neuropeptidergic terminals were stained histochemically and immunohistochemically, respectively, neuropeptide concentrations were measured by radioimmunoassay (RIA), and the results were investigated qualitatively and quantitatively by color image analyzer. The structural relation between the MC and neuropeptide terminals was studied by ultramicroscopy using in situ embedding technique. RESULTS: In IBS, the number of MC in the terminal ileum, the ileocecal junction, and the ascending colon was significantly increased (P

Chronic diarrhea is a common bowel disorder; disturbance of intestinal microorganisms may play a role in its pathogenesis. This study assessed the clinical efficacy of lyophilized, heat-killed Lactobacillus acidophilus LB versus living lactobacilli in the treatment of chronic diarrhea. One hundred thirty-seven patients with chronic diarrhea were randomly allocated to receive either a 4-week course of 2 capsules of Lacteol Fort twice a day (Lacteol group, 69 patients) or a 4-week course of 5 chewable tablets of Lacidophilin three times a day (Lacidophilin group, 64 patients). The frequency of stools was recorded quantitatively, and semiquantitative parameters such as stool consistency, abdominal pain, distention, and feeling of incomplete evacuation were evaluated. At the second and fourth week of treatment, mean bowel frequency was significantly lower in the Lacteol group than in the Lacidophilin group (1.88 +/- 1.24 vs 2.64 +/- 1.12, 1.39 +/- 0.92 vs 2.19 +/- 1.05; P

AIM: To explore the protective effects of endothelin-1 antibody (ET-1Ab) on acute gastric mucosa lesions induced by stress in rats. METHODS: Stress ulcer induced by cold-restraint-stress (CRS) was used as model in this study, different dose ET-1Ab were administered by left femoral vein prior to stress so as to observe the effects of the drug on ET-1 levels in plasma and gastric mucosa, gastric mucosa blood flow (GMBF)and ulcer index(UI) of CRS rats. RESULTS: (1) Compared with the normal control group, ET-1 levels of plasma and gastric mucosa and UI were increased significantly in the stress groups (116.2±24.7 mv and 125.1±24.2 mv vs 49.1±9.7 mv, 113.8±29.3 mv and 122.9±19. 6 mv vs 52.3±10.3 mv, 28.6±1.8 mv and 51.2±5.9 mv vs 0, P

Introduction Suicide gene therapy is a new experimental form of cancer chemotherapy that is currently being evaluated in human trials. Aim To evaluate the killing effects of the cytosine deaminase (CD) gene mediated by an adenovirus vector on human pancreatic carcinoma in vitro and in vivo. Methodology The CD gene was cloned into pAdTrack-CMV-CD, pAdTrack-CMV-CD, and pAdEasy-1, which underwent recombination in bacteria BJ5183. The newly recombinant Ad-CD containing green fluorescent protein was propagated in 293 cells and purified by cesium chloride gradient centrifugation. The human pancreatic carcinoma cell line PaTu8988/SW1990 was infected with this virus, and then 5-fluorocytosine (5-FC) was added; XTT assay was used to estimate relative numbers of viable cells. An in vivo model of pancreatic cancer was established by injecting 1.0 x 10(7) PaTu8988/SW1990 cells subcutaneously in Balb/c nude mice. When tumors were palpable, Ad-CD was injected into each tumor, and 5-FC was administered. The positive clones were selected by endonuclease digestion of the combinations, and the concentration of viral liquids containing the CD gene was 2 x 10(11) pfu/mL. Results It was found that significant cytotoxic activities were possessed by 5-FC for CD gene-transduced PaTu8988/SW1990 cells, but there was little effect on the nontransduced pancreatic carcinoma cells. The antitumor effect was observed in PaTu8988/SW1990 xenografts from nude mice with in situ CD gene transduction. Conclusion These results indicate that the CD gene mediated by adenovirus has a high level of infectivity and is efficient for gene therapy for pancreatic carcinoma.

OBJECTIVE: To investigate the visceral perception, anorectal pressure and colonic transit time (CTT) in patients with functional constipation and constipation-predominant irritable bowel syndrome (C-IBS), and to study the manometric abnormalities of these two conditions. METHODS: The CTT in patients with functional constipation and C-IBS was studied by using radiopaque markers. Rectal visceral perception thresholds, rectal compliance and anorectal pressure were examined by electric barostat. RESULTS: The CTT in both groups of constipated patients was abnormal. A lot of radiopaque markers remained in the right colon in C-IBS patients, whereas in patients with functional constipation, the radiopaque markers remained in each segment of the colon. The anorectal resting pressure, squeezing pressure and relaxation pressure were normal in both groups. Rectal compliance and defecation thresholds were much higher compared with controls, and the rectal visceral perception of functional constipation was also abnormal. CONCLUSIONS: The motility abnormalities of functional constipation and C-IBS occurred in different colonic segments. Results suggest that CTT measure­ment and anorectal manometry could be helpful in the differential diagnosis of these two conditions.

OBJECTIVE: To investigate the value of the p53 protein for diagnosing cancer in pancreatic cells obtained by using endoscopic pancreatic duct brushing. METHODS: Immunohistochemical methods were used to assay the amount of p53 protein in cytological specimens. The results were compared with those obtained by hematoxylin and eosin (H&E) staining. RESULTS: Detection of the p53 protein by staining cytological specimens with H&E diagnosed pancreatic cancer with 53% sensitivity, 100% specificity and 70% accuracy. Using immunohistochemical methods, pancreatic cancer was diagnosed with 59% sensitivity, 100% specificity and 74% accuracy. The methods in combination produced a test with 71% sensitivity, 100% specificity and 81% accuracy. CONCLUSIONS: Hematoxylin and eosin staining combined with p53 protein detection in cells obtained by using endoscopic pancreatic duct brushing is a useful tool in the diagnosis of pancreatic cancer, and in the differentiation of benign and malignant pan­creatic disease.

Background Patients with sliding hiatus hernia (HH) and reflux esophagitis (RE) usually suffer from esophageal dysmotility. The aim of the present study was to investigate the role of acid reflux and duodenal gastroesophageal reflux (DGER), esophageal manometry, and esophageal dysmotility by applying the barium meal examination. Methods RE with HH was initially diagnosed using the reflux disease questionnaire, and was further confirmed by a barium meal examination and an endoscopy. The radiographic technique was used to test for spasms, strictures, and the coarseness of the mucosa, also was to study the types of reflux and clearance. Then, the esophageal manometry, the esophageal 24-hour pH, and the bilirubin monitoring were observed. Results Fifty-five patients were diagnosed as HH combined with RE and divided into two groups according to the severity of their esophagitis: group HH1 (grades A and B) and group HH2 (grades C and D). The barium meal examination revealed that the mucosa was either granular or nodular in all cases. The dump reflux and delayed clearance were more significant in patients in the HH2 group than those in the HH1 group (P

OBJECTIVE: To investigate the structural characteristics of the cag pathogenicity island (PAI) and its significance in the classification in Chinese strains of Helicobacter pylori. METHODS: In 107 H. pylori strains isolated from Chinese patients, cagA, cagI, cagII, the cagI−cagII junction and IS605 were studied by using the polymerase chain reaction. RESULTS: The positive rates in Chinese H. pylori strains were 95.3% for cag PAI, 92.5% for cagA, 86.9% for cagI and 66.4% for cagII. There was no statistical difference among H. pylori strains from chronic gastritis, peptic ulcers or gastric carcinoma in the detectable rate of cag PAI, cagA, cagI or cagII (P > 0.05). Of the cag PAI-negative strains, four came from cases of chronic gastritis and one from a patient with cardiac cancer. The products of the cagI−cagII junction were found in only five strains. The continuous cag PAI was much more common in duodenal ulcers than in chronic gastritis (P < 0.01). The positive rates of cagI and cagII were markedly different in chronic gastritis (P < 0.05). One strain of H. pylori tested positive for cagA but negative for other regions of the cag PAI. IS605 was less common in duodenal ulcers than in chronic gastritis (P < 0.05). The amplified fragment of IS605 in one strain from a gastric carcinoma was approximately 1580 bp in size, which was much longer than that in other strains. CONCLUSION: Our results indicate that the cag PAI is very common in Chinese strains of H. pylori. The structural variety of the cag PAI might be related to the virulence of H. pylori. It is suggested that H. pylori may be classified into different virulence groups according to differences in the structure of the cag PAI.

OBJECTIVE: To determine the role of endogenous nitric oxide (NO) in gastric mucosal tolerant cytoprotection under stress and its possible mechanism. METHODS: Sprague–Dawley rats were exposed to repeated water immersion and restraint stress (WRS), during which NG-nitro-L-arginine methyl ester (L-NAME), a non-selective NO synthase inhibitor, and L-arginine (L-Arg), a substrate for NO synthesis, were administered to inhibit or promote the synthesis of endogenous NO, respectively. Gastric mucosal blood flow (GMBF) was measured with an LDF-3 Flowmeter (Electronic Instrument Factory of Nankai University, Tianjin, China), the NO level in the gastric mucosa was monitored by the Griess reaction and gastric mucosal lesions were evaluated using the ulcer index (UI). The relationships between changes in GMBF, UI and NO content in the gastric mucosa were analyzed by linear correlation analysis. RESULTS: Repeated WRS induced gastric mucosal tolerant cytoprotection and this was accompanied by increased GMBF and NO levels in the gastric mucosa. Inhibition of endogenous NO synthesis by L-NAME worsened mucosal lesions induced by single WRS and, after repeated WRS, the adaptive incremence in GMBF was abolished and the NO content in the gastric mucosa was significantly reduced. In contrast, enhancement of endogenous NO synthesis by L-Arg attenuated mucosal erosions caused by single WRS. After repeated WRS, GMBF and the NO content in the mucosa increased gradually. Mucosal lesions were negligible after rats were exposed to the fourth WRS. CONCLUSIONS: During the tolerant cytoprotection, GMBF, UI and the NO content showed regular changes and there were good relationships between them. L-NAME and L-Arg changed the levels of endogenous NO, which, accordingly, affected GMBF and the gastric tolerance. By regulating GMBF, endogenous NO may play an important role in the gastric mucosal tolerant cytoprotection under stress. Inhibition of the synthesis of NO delayed the induction of tolerant cytoprotection, whereas increased NO synthesis promoted cytoprotection.

The phase velocity dispersion of seismic surface waves is computed from the clear and reliable Rayleigh wave records of 21 seismic stations and 43 paths in east Chinese continent. We obtain the distribution of phase velocity dispersion by Talantola probability inversion method. The image of 3-D shear wave velocity in the crust and upper mantle is inverted by the phase velocity dispersion curves in the investigated region. Then we obtain the S wave velocity structure in the crust and upper mantle of east Chinese continent. The results show that the over all tendency of the thickness of east China crust is thin in the east and thick in the west. To the west of 105° E, the thickness of crust gradually increases to 55km. There is an ‘h’ form slope belt of the crust thickness. In the region of west Henan and south Shanxi provinces the crust is relatively thin. The thickness of crust in Dabie mountain and Taishan mountain are thicker than surrounding region. But in the Qinling mountain region the crust is not thicker. In North China region the top interface of the low velocity layer (LVL) of the upper mantle is rather shallow. It is about 80–90km. In the region of Eerduosi depression, Sichuan platform trough and Guizhou-Hunan region it is about 120–130km. In the east Yangzi block as well as east and center South China fold system velocity in the top upper mantle is relatively low and the velocity contrast of LVL is not evident. In the west of Yunnan-Guizhou fold system there is no LVL within the top 200km of the upper mantle.

We present a 3-D minimum structure inversion algorithm for d.c. resistivity data, using conjugate gradient (CG) relaxation techniques. Firstly, to solve the minimum structure inverse equations, the CG relaxation techniques only require the multiplications of the Jacobian matrix G and its transpose GT with ab itrary vectors, xand y respectively. When the Rodi method is introduced to compute the G, Gx and GTy can be obtained by one forward calculation in each inverse iteration. Therefore the inversion is computed much quickly. In this way we can also avoid direct computing the inverses of G and GTG and save the huge storage for G and GTG. In addition, as there are too many inversion parameters, which effectively erase unnecessary structures and obtain trustworthy results close to true model, we impose a smoothness constraint on the model in minimum structure inversion to obtain the smoothest solution. We combine these methods and techniques into 3-D resistivity inversion and obtain very promising results with 3-D synthetic data. We also developed new iterative technique to deal with the problem of very slow convergence rate in the traditional minimum structure inversion. This technique requires no more than ten iterations to reach the convergence.

On the basis of data of long period Rayleigh surface wave, we select 43 two-station paths which cover the eastern China thoroughly. By using the improved method of multi-filtration, we obtain the group velocity and amplitude spectrum, and then get attenuation factor for each paths. We employ Talentola inversion method to get local attenuation factor, and further invert the three-dimension Qβ image under the crust and upper mantle in the eastern Chinese continent. The Qβ image shows the following basic characters. There is correlation between the seismic activity and Qβ structure under the crust and upper mantle in North China region. The Yangtze block begins to collide with and subduct to the North China block from the southern border of the Qinling in the southern Shaanxi. In the large part of Yangtze quasi-platform appear an obvious high Qβ area at 88 km deep. In the east of Sichuan depression platform, the juncture of Sichun and Guizhou, and the Jiangnan block near the juncture of Guizhou and Hunan, the lateral variation of Qβ in the crust is little, and there is a high-Qβ layer no thinner than 40 km in the top mantle. In the Dian-Qian fold and fracture region between Yunnan and Guizhou, the vertical variation of Qβ at the region of the crust and upper mantle is little, there is a low-Qβ layer in the top mantle, about 40 km thick, low-Qβ layer of the upper mantle begins to appear at about 95 km deep. In the east of Yangtze quasi-platform and the central and eastern part of the South China fold system, the Moho is smooth, the lateral variation of Qβ in the crust is also little, low-Qβ layer of the upper mantle begins to appear at about 85 km deep.

The ‘auxiliary’ symmetry properties of the system matrix (symmetry with respect to the trailing diagonal) for a general anisotropic dissipative medium and the special form for a monoclinic medium are revealed by rearranging the motion–stress vector. The propagator matrix of a single-layer general anisotropic dissipative medium is also shown to have auxiliary symmetry. For the multilayered case, a relatively simple matrix method is utilized to obtain the inverse of the propagator matrix. Further, Woodhouse’s inverse of the propagator matrix for a transversely isotropic medium is extended in a clearer form to handle the monoclinic symmetric medium. The properties of a periodic layer system are studied through its system matrix Aly , which is computed from the propagator matrix P. The matrix Aly is then compared with Aeq , the system matrix for the long-wavelength equivalent medium of the periodic isotropic layers. Then we can find how the periodic layered medium departs from its long-wavelength equivalent medium when the wavelength decreases. In our numerical example, the results show that, when λ/D decreases to 6–8, the components of the two matrices will depart from each other. The component ratio of these two matrices increases to its maximum (more than 15 in our numerical test) when λ/D is reduced to 2.3, and then oscillates with λ/D when it is further reduced. The eigenvalues of the system matrix Aly show that the velocities of P and S waves decrease when λ/D is reduced from 6–8 and reach their minimum values when λ/D is reduced to 2.3 and then oscillate afterwards. We compute the time shifts between the peaks of the transmitted waves and the incident waves. The resulting velocity curves show a similar variation to those computed from the eigenvalues of the system matrix Aly , but on a smaller scale. This can be explained by the spectrum width of the incident waves.

Seismic waves generated in elastic media by ellipsoidal cavities driven by low frequency pressure can be solved by Eshelby’s method. In this paper we prove that this method, originally presented for elastostatic ellipsoidal inclusion problems, can also be applied to dynamic problems on the assumption that wavelengths are much longer than the dimensions of cavities. Comparison between the approximate solution for spherical cavities and its relevant precise solution shows that this method may be used for radii of cavities smaller than 100 m and for frequencies below 10 Hz. By this approach we show that, for low frequency seismic waves in the far-field an explosive load on an ellipsoidal cavity can be equivalent to three dipoles oriented along the principal axes of that cavity. Seismic radiation patterns are given analytically and results thus obtained show that an explosion detonated in an ellipsoidal cavity may radiate significant S waves.

To get better denoising results, the prior knowledge of nature images should be taken into account to regularize the ill-posed inverse problem. In this paper, we propose an image denoising algorithm via non-local similar neighbor embedding in sparse domain. Firstly, a local statistical feature, namely histograms of oriented gradients of image patches is used to perform the clustering, and then the whole training data set is partitioned into a set of subsets which have similar local geometric structures and the centroid of each subset is also obtained. Secondly, we apply the principal component analysis (PCA) to learn the compact sub-dictionary for each cluster. Next, through sparse coding over the sub-dictionary and neighborhood selecting, the image pa tch to be synthesized can be approximated by its top k neighbors. The extensive experimental results validate the effective of the proposed method both in PSNR and visual perception. Key words: image denoising, non-local prior, sparse representation, neighbor embedding

The different polarization phase angle (orientation) low-resolution images of the same scene have much redundant and complementary information which can be used to construct a high-resolution image. In this paper, we propose a super-resolution (SR) algorithm via sparse and redundant representation with considering the non-local self-similarity in different polarization orientation images. As the redundant over-complete dictionary has many irrelevant atoms which not only reduce the computational efficiency in sparse coding but also reduce the representation accuracy, we learn a local dictionary by applying the principal component analysis (PCA) technique. For an image patch to be coded, the best fitted sub-dictionary is adaptively selected by an adaptive sparse domain selection strategy. To improve the stability and accuracy of sparse coding, the centralized sparse coding algorithm is used. The extensive experimental results demonstrated that the proposed method can effectively reconstruct the polarization image with edge structure preserved and detailed information obtained in terms of PSNR, SSIM and visual perception.

In this paper we analyse the polarization imaging theory and the commonly process of the polarization imaging detection. Based on this, we summarize our many years’ research work especially in the mechanism, technology and system of the polarization imaging detection technology. Combined with the up-to-date development at home and abroad, this paper discusses many theory and technological problems of polarization imaging detection in detail from the view of the object polarization characteristics, key problem and key technology of polarization imaging detection, polarization imaging detection system and application, etc. The theory and technological problems include object all direction polarization characteristic retrieving, the optical electronic machinery integration designing of the polarization imaging detection system, the high precision polarization information analysis and the polarization image fast processing. Moreover, we point out the possible application direction of the polarization imaging detection technology both in martial and civilian fields. We also summarize the possible future development trend of the polarization imaging detection technology in the field of high spectrum polarization imaging. This paper can provide evident reference and guidance to promote the research and development of the polarization imaging detection technology.

In this paper we propose a polarization image fast fusion approach based on online dictionary learning for sparse non-negative matrix factorization, aiming at improving the efficiency of fusion methods for polarization image based on non-negative matrix factorization. Firstly, all of the polarization parameter images are taken as source data sets for sparse non-negative matrix factorization using online dictionary learning algorithm, so as to extract three feature basis images. Then, after histogram matching, the three feature basis images are mapped into three color channels of IHS color space. Finally, the fused image is achieved via the transform from IHS to RGB color model. Experimental results show that, the proposed method not only has better capacity of color representation capability and effectively pop out detailed information of objects but enhances the running efficiency evidently as well.

AIM: To explore the diagnostic and therapeutic value of endoscopic retrograde cholangiopancreatography (ERCP) in children with pancreatitis.

Objective Patients with dyspepsia with alarm features are suspected of having upper gastrointestinal (GI) malignancy; however, the true value of alarm features in predicting an underlying malignancy for patients with dyspepsia with high background prevalence of Helicobacter pylori infection and upper GI malignancy is uncertain. The aim of the present study was to determine the diagnostic accuracy of alarm features in predicting upper GI malignancy by reviewing an endoscopic database consisting of >100 000 Chinese patients. Methods A retrospective analysis of prospectively collected data was conducted in a single tertiary medical centre. Consecutive patients who underwent oesophagogastroduodenoscopy (OGD) for dyspepsia in 1996–2006 were enrolled. The data including gender, age, symptoms, and endoscopic and pathological findings were analysed. The main outcome measure was the diagnostic accuracy of individual alarm feature. Results 102 665 patients were included in the final analysis. Among all the 4362 patients with malignancy, 52% (2258/4362) had alarm features. Among 15 235 patients who had alarm features, 2258 (14.8%) were found to have upper GI malignancy. The pooled sensitivity and specificity of the alarm features were 13.4% and 96.6%, respectively. Only the feature of dysphagia in patients between 36 and 74 years old had a positive likelihood ratio (PLR) >10 for malignancy prediction, while all other alarm features in other age groups had a PLR Conclusions For uninvestigated Chinese patients with dyspepsia with high background prevalence of H pylori infection and upper GI malignancy, alarm features and age, except for dysphagia in patients between 36 and 74 years old, had limited predictive value for a potential malignancy; therefore, prompt endoscopy may be recommended for these patients. However, less invasive, inexpensive screening methods with high diagnostic yield are still needed to reduce unnecessary endoscopy workload.

OBJECTIVES So far, there are no investigations about the role of histone deacetylase 1 (HDAC1) in tumorigenesis of pancreatic ductal adenocarcinoma. This study was designed to elucidate the roles and mechanisms of HDAC1 in tumorigenesis of pancreatic ductal adenocarcinoma. METHODS Real-time reverse transcription-polymerase chain reaction and immunohistochemistry techniques were adopted to detect the expression of HDAC1 in human pancreatic ductal adenocarcinoma tissues and paired paracancerous tissues. The roles of HDAC1 in human pancreatic cell line PaTu8988 were investigated using siRNA. RESULTS Histone deacetylase 1 mRNA in pancreatic cancer tissues were significantly higher than in paracancerous tissues (P < 0.05). Immunohistochemistry showed that the indices of HDAC1 in pancreatic cancer tissues and paracancerous tissues were 56.4% (SD, 23.1%) and 6.7% (SD, 5.0%), respectively (P < 0.001). Knockdown of HDAC1 can generate a remarkable defect in proliferation and also can significantly induce apoptosis and S-phase arrest in PaTu8988 cells (P < 0.05). The Bcl-2 mRNA expression was significantly downregulated, whereas the p21 and Bax mRNA expression were significantly upregulated. CONCLUSIONS The HDAC1 overexpression might play an important role in tumorigenesis of pancreatic cancer. Our data support the development of selective inhibitors targeting HDAC1 for the treatment of pancreatic ductal adenocarcinoma. Histone deacetylase 1 could be a new gene therapy target in pancreatic ductal adenocarcinoma.

Analyses of pancreatic juice by proteomics have identified many proteins that are overabundant in pancreatic cancer (PC) juice. The mechanism by which secretion of these proteins occur remains unclear. Pancreatic juice was collected from patients with three pancreatic diseases: PC, chronic pancreatitis (CP), and simple choledocholithiasis (CDS), and analyzed by 2-DE, MALDI-TOF/MS, and Western blot. Five PC cell lines, 30 PC tissues and their corresponding adjacent pancreatic tissues were used to validate the expression of genes which code for overabundant proteins in PC juice. The mRNA and protein levels were measured by RT-PCR and immunohistochemistry, respectively. Using proteomics, it was demonstrated that the protein transthyretin (TTR) was upregulated more than 2-fold in PC juice compared with CP and CDS, while apolipoprotein A-I, lithostathine, and regenerating islet-derived 1 beta precursor were downregulated more than 2-fold. Western blots confirmed that TTR was overabundant in the PC juice. However, TTR mRNA was not detected in any of the five PC cell lines, and was only detected in islet cells. By microscopy, it was shown that islet architecture was almost completely destroyed, and the islet's maximum diameter appeared larger in PC tissues than in normal. Some overabundant proteins in PC juice, such as TTR expressed only in islets, leak into the pancreatic ductal system due to hyperplasia and architectural damage in PC tissues. The destruction of organ and tissue architecture by tumor growth may result in novel tumor markers even if the markers are not secreted directly by tumor cells.

To investigate the brain mechanisms for esophageal visceral hypersensitivity.Thirty-one non-erosive reflux disease (NERD) patients, 21 in the group of NERD with esophageal hypersensitivity (NERD-H) and 10 in the group of NERD with normal esophageal sensation (NERD-N), 13 patients with erosive esophagitis (EE), and 12 healthy volunteers, all sex- and age-matched, underwent whole brain blood oxygenation level dependent (BOLD) fictional magnetic resonance imaging (fMRI) to record the cortical fMRI response to intraesophageal perfusion of normal saline or dilute hydrochloric acid.The main centers affected in the NERD-H patients included the secondary somatosensory cortex (SII), primary somatosensory cortex (S1), right prefrontal cortex (PFC), right orbitofrontal cortex (OFC), insular cortex, amygdala, striatum, motor cortex and its supplementary area, and cerebellum cortices, which form part of the matrix controlling emotional, autonomic modulatory responses to pain. The peak fMRI signal intensity and average maximum percent signal increase in the regions of interest (ROI) at above-mentioned brain areas of the NERD-H group were significantly stronger than those of the NERD-N and control groups (all P0.01). The peak image intensity of the anterior cingulate gyrus (ACC) of NERD-H group was 562 +/- 104, significantly lower than that of the control group (587 +/- 126, P0. 05), but significantly higher than that of the EE group (535 +/- 91, P0.05). The timeline of activation and deactivation events of particular ROI differentiate the four groups. The initial image latency and peak fMRI latency after hydrochloric acid perfusion of the NERD-H patients were 1.7 min +/- 0.9 min and peak 4. 5 min +/- 1.3 min respectively, both significantly shorter than those of the NERD-N group (4.0 min +/- 1.1 min and 6.8 min +/- 1.6 min respectively, both P0.01) and those of the control group (5. 4 min +/- 1.7 min and 7.2 min +/- 1.5 min respectively, both P0.01). The range of deactivation of SII and R-PFC of the NERD-H group were 26.5% +/- 5.4% and 20.3% +/- 3. 0% respectively, both significantly greater than those of the NERD-N group (8.2% +/- 2.2% and 16.4% +/- 3.6% respectively, both P0.05) and those of the EE group (11.9% +/- 4.8% and 11.7% +/- 3.1% respectively, both P0.01). The range of deactivation in ACC of the control group was 16.9% +/- 2.5%, significantly greater than those of the NERD-H and EE groups (11.8% +/- 2.8% and 6.4% +/- 1.0% respectively, both P0.05).The function of central nervous system to integrate and manage the convergence information becomes abnormal under the status of esophageal visceral hypersensitivity.

To investigate the clinical value of endoscopic ultrasonography (EUS) and intraductal ultrasonography (IDUS) compared with the other imaging examination in the early diagnosis of pancreatic tumor.Retrospect studied of 188 cases of small pancreatic lesions (less than 3 cm in diameter) detected by EUS, IDUS and the other imaging examination at Changhai hospital from October 1992 to September 2006.(1) The accurate rate of small pancreatic cancer diagnosed by EUS was 95.6%, and it is better compared with US (58.6%), CT (77.4%), MRI (76.2%) and ERCP (85.3%). The most common endosonographic features of small pancreatic cancer were alike round, irregular edge, hypoechoic mass with uniformity internal echo. (2) IDUS was performed in 25 cases of small pancreatic lesions, the accurate rate of diagnosis was 100% (25/25), and it is better compared with US 32.0% (8/25), CT 52.9% (9/17) and MRI 57.9% (11/19). (3) EUS guided FNA (EUS-FNA) was performed in 18 cases of small pancreatic lesions, the accurate rate of diagnosis was 66.7% (12/18). (4) The accurate rate of pseudocyst diagnosis by EUS was 100.0% (27/27), it is better compared with US 52.0% (13/25), CT 66.7% (12/18), MRI 82.4% (14/17) and ERCP 78.9% (15/19); and the overall accurate rate of diagnosis of cystic pancreatic tumors by EUS was 57.7% (15/26), it is better compared with US 19.2% (5/26), CT 36.4% (8/22), MRI 37.5% (6/16) and ERCP 50.0% (7/14).EUS and IDUS were better than the other imaging examinations in the detection of small pancreatic tumors.

Keywords: Barrett's esophagus; consensus; diagnosis; erosive esophagitis; gastroesophageal reflux disease; non-erosive reflux disease; treatment

Hedgehog (Hh) signaling pathway is crucial in growth and patterning during embryonic development. Recent data have shown an association of its activation with cancer formation and maintenance. A ligand-dependent activation, where Hh components (SHH, PTCH1, Smo and GLi1) are aberrantly expressed with PTCH1 being a negative feedback regulator, is a newly identified mechanism for pancreatic carcinogenesis. In this study, we developed a cell-specific cytotoxic model for the treatment of human pancreatic cancer (HPC) in which expression of antisense Smo (SAS) was under the control of the PTCH1 promoter (ptch/p) delivered by an adenoviral vector (Ad-ptch/p-SAS). We observed that the cell-specific cytotoxicity in HPC cells depended on the expressions of inherent PTCH1, Smo and GLi1 in the target cells in which the Hh pathway was presumed to be activated. Fluorescence-activated cell sorting analysis indicated that the cell death was apoptosis. Western blot showed that Smo protein in the infected cells significantly decreased. Furthermore, an in vivo experiment demonstrated that such Hh activity-cell-specific cytotoxicity was achieved by daily intratumoral injection of Ad-ptch/p-SAS (10(9) plaque-forming unit) for 5 days. Our study suggests that targeting at the Hh signaling pathway may be an effective novel gene therapeutic strategy alone or in combination with other agents for the treatment of pancreatic cancer.

To study the mechanism of visceral hypersensitivity in patients with non-erosive gastroesophageal reflux disease (NERD) and to get further objective evidence in the abnormal alteration of the afferents involved in mediating esophageal sensation by cerebral evoked potentials (CEP).We recruited 21 NERD patients and 10 normal healthy volunteers for the study. Mechanical distention stimulation was performed using a balloon-affixed polyvinyl multilumen catheter. First, maximally tolerated pain threshold of all subjects were recorded, then esophageal mechanical stimulation at an intensity of 75% maximum tolerated intensity and a frequency of 0.2 Hz was inflated in a total of 64 times by means of a computer-controlled barostat. The alternation of esophageal CEP was recorded before and after acid perfusion with a multi-channel international 10-20 system of electroencephalograph.Esophageal mucosal distention may evoke recognizable and reproducible multi-peak CEP. CEP morphology of the NERD patients was characterized by randomly distributed patterns and the peak latencies for N1, P1, and N2 were significantly shorter for mechanical stimulation as compared with the control group (respectively, P = 0.016, 0.003, 0.031), and the amplitude of the P1-N2 components was significantly increased in NERD patients (P = 0.03).Characterization and alternation of CEP morphology and peak latencies and P1-N2 amplitudes elicited by esophageal distention in NERD patients provides evidence for defective hypersensitivity of afferent neural pathways and cortical processing.

Background Reports on endoscopic management of ingested foreign bodies of the upper-GI tract in China are scarce. Objective To report our experience and outcome in the management of ingestion of foreign bodies in Chinese patients. Setting and Patients Between January 1980 and January 2005, a total of 1088 patients (685 men and 403 women; age range, 1 day to 96 years old) with suspected foreign bodies were admitted to our endoscopy center. Interventions All patients underwent endoscopic procedure after admission. Main Outcome Measurements Demographic and endoscopic data, including age, sex, and referral sources of patients, types, number and location of foreign bodies, associated upper-GI diseases, endoscopic methods, and accessory devices for removal of foreign bodies were collected and analyzed. Results A total of 1090 foreign bodies were found in 988 (90.8%) patients. The types of foreign bodies varied greatly: mainly food boluses, coins, fish bones, dental prostheses, or chicken bones. The foreign bodies were located in the pharynx (n = 12), the esophagus (n = 577), the stomach (n = 441), the duodenum (n = 50), and the surgical anastomosis (n = 10). The associated GI diseases (n = 88) included esophageal carcinoma (33.0%), stricture (23.9%), diverticulum (15.9%), postgastrectomy (11.4%), hiatal hernia (10.2%), and achalasia (5.7%). A rat-tooth forceps and a snare were the most frequently used accessory devices. The success rate for foreign-body removal was 94.1% (930/988). Conclusions Ingestion of foreign bodies is a common clinic problem in China. Endoscopy procedures are frequently performed, and a high proportion of patients with foreign bodies require endoscopic intervention.

OBJECTIVE: To investigate the dynamic changes of mitogen-activated protein kinase (MAPK) signal transduction in rats with severe acute pancreatitis (SAP). METHODS: The SAP model was induced by infusing the bilio-pancreatic duct of 56 Sprague-Dawley rats with 5% sterile sodium taurocholate solution. The rats were randomly divided into seven groups: control group, 0.5 h postoperative group, 1 h group, 3 h group, 6 h group, 12 h group and 24 h group. Western blot analysis was used to determine the activities of p38 MAPK and c-Jun N-terminal kinase (JNK) in the pancreas and lungs. RESULTS: In the rats of the control group, basal p38MAPK activity could be detected but not that of JNK. After SAP was induced, the p38MAPK activity in the pancreas increased markedly and peaked at 3 h, but in the lung it peaked at 6 h. The p38MAPK activity in the pancreas and lungs was significantly higher than the basal activity at the 24 h time point. The activity of JNK was only increased at the 12 h point and was not detectable at 24 h. CONCLUSION: The MAPK signal transduction pathway, in particular p38MAPK, plays an important role in the pathogenesis of SAP.

OBJECTIVE: The incidence of pancreatic cancer is increasing in China, and in many patients the surrounding lymphatics have already been invaded and there is blood-borne metastasis at the time of diagnosis. Additionally, pancreatic cancer is largely refractory to conventional therapies. Therefore, to improve its prognosis, it is important to resolve the problem of its growth. Angiotensin II type 1 receptor (AT1) stimulates the growth and angiogenesis of pancreatic cancer and a selective AT1 antagonist could inhibit these effects. The present study aimed to investigate the expression of AT1 in pancreatic cancer cell lines to provide the theoretical basis for its treatment. METHODS: The pancreatic cancer cell lines were SW1990, PaTu8988s and PANC-1. RT-PCR was used to detect the AT1 mRNA expression, and ABC immunocytochemical staining and SDS-PAGE were used to detect the expression of AT1 protein. RESULTS: Both AT1 mRNA and protein were expressed in all three cell lines. The AT1 protein was found on the cell membrane and in the cytoplasm of these cells. The AT1 protein (44 × 103) was also demonstrated by SDS-PAGE. CONCLUSION: The results suggest that AT1 plays an important role in the growth of pancreatic cancer and its inhibition may be a therapeutic strategy.

OBJECTIVE: Visceral hypersensitivity is highly prevalent in most functional bowel disorders, such as irritable bowel syndrome (IBS), and activation of intestinal mast cells (MC) may play a role because they have been found in close proximity to gastrointestinal mucosal sensory nerve terminals containing neuropeptides and a bi-directional pathway connecting the central nervous system, gut, and MC has been demonstrated. The current study appraised the status of rectal visceral perception, as well as the changes in the MC and substance P (SP) in the intestinal mucosa of patients with IBS. METHODS: The study group comprised 42 patients with IBS and 19 healthy subjects who underwent anorectal manometry and rectal perception thresholds to balloon distension. The MC and the SP-ergic terminals in the mucosa were stained for respective histochemical and immunohistochemical investigations. The results were presented both qualitatively and quantitatively by color image analyzer, based on analysis of the intensity and area of stained fibrils. The structural relationship between the MC and nerve terminals was studied by electron microscopy, using an in situ embedding technique. RESULTS: The anorectal resting pressure, squeezing pressure and relaxation pressure were normal in both groups. The sensation threshold, defecation threshold and pain threshold in diarrhea-predominant IBS and the pain thresholds in constipation-predominant IBS were much lower than in the controls. Rectal compliance decreased in IBS. The number of MC in the terminal ileum, the ileocecal junction and the ascending colon was significantly elevated in IBS (P

To investigate the role of duodenogastroesophageal reflux (DGER) in the pathogenesis of gastroesophageal reflux disease (GERD) and its value for the diagnosis of non-erosive reflux disease (NERD).95 cases of GERD were divided into two groups according to endoscopic findings: reflux esophagitis (RE) (n = 51) and NERD (n = 44). Simultaneous 24-hour esophageal pH and bilirubin monitoring were performed.The index values of DGER in RE group such as percent of time with Abs0.14, total reflux time and time with reflux5 min were 19.05 +/- 23.44, 30.56 +/- 34.04 and 5.90 +/- 6.37 respectively, they were significantly higher than those of NERD, 7.26 +/- 11.08, 15.68 +/- 20.92 and 2.59 +/- 3.57, respectively (P0.05), but no significant difference was found in acid reflux. The occurrence of DGER was more common in more severe esophagitis. Isolated DGER were found in 18.2% of NERD, and combined bilirubin monitoring could elevate the positive diagnosis rate of NERD from 65.9% to 84.1%.DGER could be present isolatedly and played an obvious role in the genesis of RE and GERD symptoms. Simultaneous 24-hour esophageal pH and bilirubin monitoring were helpful for the diagnosis of NERD.

AIM: To study the value of monitoring K-ras point mutation at codon 12 and telomerase activity in exfoliated cells obtained from pancreatic duct brushings during endoscopic retrograde cholangiopancreatography (ERCP) in the diagnosis of pancreatic cancer. METHODS: Exfoliated cells obtained from pancreatic duct brushings during ERCP were examined in 27 patients: 23 with pancreatic cancers, 4 with chronic pancreatitis. K-ras point mutation was detected with the polymerase chain reaction and restriction fragment-length polymorphism (PCR-RFLP). Telomerase activity was detected by PCR and telomeric repeat amplification protocol assay (PCR-TRAP-ELISA). RESULTS: The telomerase activities in 27 patients were measured in 21 exfoliated cell samples obtained from pancreatic duct brushings. D450 value of telomerase activities in pancreatic cancer and chronic pancreatitis were 0.446 ± 0.27 and 0.041 ± 0.0111, respectively. Seventy-seven point eight percent (14/18) of patients with pancreatic cancer and none of the patients with chronic pancreatitis showed telomerase activity in cells collected from pancreatic duct brushings when cutoff value of telomerase activity was set at 2.0. The K-ras gene mutation rate (72.2%) in pancreatic cancer was higher than that in chronic pancreatitis (33.3%) (P < 0.05). In considering of both telomerase activities and K-ras point mutation, the total positive rate was 83.3% (15/18), and the specificity was 100%. CONCLUSION: Changes of telomerase activities and K-ras point mutation at codon 12 may be an early event of malignant progression in pancreatic cancer. Detection of telomerase activity and K-ras point mutation at codon 12 may be complementary to each other, and is useful in diagnosis of pancreatic cancer.