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The aim of this study was to determine whether asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase (NOS), is responsible for the detrimental effects of nicotine on ethanol-induced gastric mucosal injury and its underlying mechanisms. Gastric mucosal injury was induced by an injection of ethanol in the stomach in rats. Animals were pretreated with nicotine for 28 days before ethanol injection. The gastric mucosal ulcer index (UI) and the levels of ADMA and NO in gastric juice were determined. In vitro, the cultured mucosal epithelial cells were treated with nicotine in the presence or absence of ethanol. The concentration of ADMA in the culture medium and the ratio of cell apoptosis were measured, and the effect of nicotine or ADMA alone on cell apoptosis was also examined. In rats treated with ethanol, the UI and ADMA levels were increased and the NO level was decreased, and these effects of ethanol were augmented by pretreatment with nicotine. Administration of nicotine alone did not show significant impact on UI, ADMA level, or NO level. In vitro, incubation of human epithelial cells with ethanol induced cell injury accompanied by increased ADMA levels in the culture medium, an effect which was amplified in the presence of nicotine. Similarly, ethanol was able to induce epithelial cell apoptosis that was exacerbated by nicotine. Incubation of epithelial cells with nicotine alone did not induce cell apoptosis, but administration of ADMA alone did induce cell apoptosis. The results suggest that the gastric mucosal injury induced by ethanol is augmented by nicotine, which is related to the increased ADMA level. Key words: nicotine, ethanol, gastric ulcer, ADMA, apoptosis. La presence etude a pour but de determiner si la dimethylarginine asymetrique (ADMA), un inhibiteur endogene de la monoxyde d'azote synthase (NOS), est a l'origine des effets deleteres de la nicotine sur la lesion de la muqueuse gastrique induite par l'ethanol et sur ses mecanismes sous-jacents. On a induit la lesion de la muqueuse gastrique par une injection d'ethanol dans l'estomac des rats. Les animaux ont ete pretraites avec de la nicotine durant 28 jours avant l'injection de 1'ethanol. On a determine l'indice d'ulcere (IU) de la muqueuse gastrique et les taux d'ADMA et de NO dans le suc gastrique. In vitro, on a traite les cellules epitheliales cultivees de la muqueuse avec de la nicotine, en presence et en 'absence d'ethanol. On a mesure les concentrations d'ADMA dans le milieu de culture et le ratio de 1'apoptose cellulaire, et examine l'effet de la nicotine on de 'ADMA sur 1'apoptose des cellules. Chez les rats traites avec 1'ethanol, l'IU et le taux d'ADMA ont augmente et le taux de NO a diminue, et ces effets ont ete amplifies par le pretraitement a la nicotine. L'administration de nicotine uniquement n'a pas eu d'effet signifcanf sur l'IU, le taux d'ADMA et le taux de NO. In vitro, l'incubation des cellules epitheliales avec l'ethanol a induit une lesion cellulaire accompannee de l'augmentation du taux d'ADMA dans le milieu de culture, un effet qui a ete amplifie en presence de nicotine. De meme, 1'ethanol a pu induire 1'apoptose des cellules epitheliales, laquelle a ete exacerbee par la nicotine. L'incubation des cellules epitheliales en presence de nicotine uniquement n'a pas induit d'apoptose cellulaire; toutefois, 1'apoptose a pu etre induite par l'administration d'ADMA uniquement. Les resultats donnent a penser que la lesion de la muqueuse gastrique induite par 1'ethanol est amplifiee par la nicotine, un effet qui est associe a l'augmentation du taux d'ADAM. Mots-cles : nicotine, ethanol, ulcere gastrique, ADMA, apoptose. [Traduit par la Redaction], Introduction Smoking is a well-recognized risk factor that promotes the development of many diseases such as lung cancer, atherosclerosis, and hypertension. In addition to the respiratory system, the upper digestive [...]

Aim: To determine the efficacy profiles of different concentrations of Lactobacillus acidophilus (L. acidophilus) for treating colitis using an experimental murine model., Methods: Colitis was established in 64 BALB/c mice by adding 5% dextran sodium sulfate (DSS) to the drinking water and allowing ad libitum access for 7 d. The mice were then randomly divided into the following control and experimental model groups (n = 8 each; day 0): untreated model control; negative-treatment model control (administered gavage of 1 mL/10 g normal saline); experimental-treatment models C4-C8 (administered gavage of 10(4), 10(5), 10(6), 10(7), or 10(8) CFU/10 g L. acidophilus, respectively); positive-treatment model control (administration of the anti-inflammatory agent prednisone acetate at 45 μg/10 g). Eight mice given regular water (no DSS) and no subsequent treatments served as the normal control group. Body weight, fecal traits, and presence of fecal occult blood were assessed daily. All animals were sacrificed on post-treatment day 7 to measure colonic length, perform histological scoring, and quantify the major bacteria in the proximal and distal colon. Intergroup differences were determined by one-way ANOVA and post-hoc Student-Newman-Keuls comparison., Results: All treatments (L. acidophilus and prednisone acetate) protected against colitis-induced weight loss (P < 0.05 vs model and normal control groups). The extent of colitis-induced colonic shortening was significantly reduced by all treatments (prednisone acetate > C4 > C5 > C7 > C8 > C6; P < 0.05 vs untreated model group), and the C6 group showed colonic length similar to that of the normal control group (P > 0.05). The C6 group also had the lowest disease activity index scores among the model groups. The bacterial profiles in the proximal colon were similar between all of the experimental-treatment model groups (all P > 0.05). In contrast, the bacterial profile in the distal colon of the C6 group showed the distinctive features (P < 0.05 vs all other experimental-treatment model groups) of Lactobacillus sp. and Bifidobacterium sp. being the most abundant bacteria and Staphylococcus aureus being the least abundant bacteria., Conclusion: The most therapeutically efficacious concentration of L. acidophilus (10(6) CFU/10 g) may exert its effects by modulating the bacterial profile in the distal colon.

Nitric oxide (NO), a multifunctional endogenous gas molecule, is metabolized from L-arginine by enzymatic reaction in the presence of nitric oxide synthase. NO, an important gas signaling molecule, is a gastric mucosa protective factor that contributes significantly to maintain normal gastric mucosa integrity. NO increases gastric mucosa blood flow, regulates the secretion of mucus and bicarbonate, and inhibits the secretion of gastric juice. Asymmetric dimethylarginine (ADMA) has been identified as the major endogenous inhibitor of nitric oxide synthase. The function of ADMA is to decrease NO production via inhibiting nitric oxide synthase activity. Besides inhibiting NO synthesis, ADMA also directly induces oxidative stress and cell apoptosis, and participates in inflammation reaction. Its systemic accumulation was observed in conjunction with several cardiovascular and metabolic diseases. ADMA also mediates gastric ulcer injury induced by ethanol, stress, helicobacter pylori and indomethacin. The mechanism of ADMA directly producing adverse effect in gastric mucosa is incompletely understood. It is widely accepted that NO bioavailability decrease is the majority reason. Promotion of apoptosis and aggravation of inflammation may be other important mechanisms of ADMA-induced gastric injury. ADMA might be a novel clinical and experimental biomarker related to gastric mucosa disorder. Although therapeutic tool targeting to ADMA is available in multiple cardiovascular diseases, it is unknown in gastrointestinal disease. The strategy to inhibit ADMA is beneficial to gastric ulcer induced by ethanol in rats. Thus, ADMA might be a candidate of therapeutic target in gastric mucosa damage.

Objective: To investigate the clinical features of Crohn disease according to the Montreal classification., Methods: Clinical data of 43 surgical patients with Crohn disease (surgical group) and 125 non-surgical patients with Crohn disease (non-surgical group) were retrospectively analyzed and compared between two groups. The Montreal classification was used., Results: In the surgical group, 28 patients (65.1%) were A2, 14 (32.6%) were A3 and only one was A1, which was not significantly different as compared to the non-surgery group. The proportions of L1, L2, L3, and L4 subtype in the surgical group were 41.9%, 25.6%, 30.2%, and 2.3%, respectively, which was not significantly different as compared to that in the non-surgery group. In the surgical group,B1 disease was found in 1 case (2.3%), B2 in 26 cases (60.5%), and B3 in 16 cases (37.2%), while in the non-surgical group, B1 was found in 79 cases (63.2%), B2 in 44 cases (35.2%) and B3 in 2 cases (1.6%). Differences were significant between two groups in disease behavior (P=0.001, P=0.004, P=0.001)., Conclusions: Most surgical patients of Crohn disease are A2. L1 and L3 are the main lesion location. As disease behavior, B2 and B3 are the main reasons for operation.

Objective: To evaluate the diagnostic valve of double balloon enteroscopy in patients with obscure abdominal pain and analyze the etiology of chronic abdominal pain resulted from enteral diseases., Methods: Sixty-seven cases with chronic abdominal pain underwent a previous negative gastroscopy, colonoscopy, gastrointestinal barium, B ultrasound and electrocardiogram were received double balloon enteroscopy during June 2005 to June 2008., Results: Thirty-six of 67 patients was done by enteroscopy via anus, and 19 cases via oral, and 12 cases via both anus and oral. The lesions were found in 41 of the 67 patients, with overall diagnostic yield of 61.19%. Among 41 cases of abdominal pain resulted from small bowel diseases, Crohn's disease were found in 15 cases (36.59%), non-specific small enteritis in 10 cases (24.39%), tumors in 8 cases (19.51%), other enteral diseases in 8 cases (19.51%)., Conclusions: Double balloon enteroscopy was a diagnostic modality with a high diagnostic value for obscure abdominal pain resulted from small bowel diseases. The most common causes of obscure abdominal pain were Crohn's disease, non-specific small enteritis and tumors.

Objective: To construct the plasmid of human vascular endothelial cell growth factor165 and green fluorescence protein report gene eukaryotic expression vector of fusion protein pEGFP /hVEGF165, and to detect its expression in vascular endothelial cells., Methods: We amplified full-length of gene VEGF165 by PCR, cloned in direction in multiple clone sites of pEGFP-N1, constructed recombinant plasmid of pEGFP/hVEGF165. Through enzyme digestion, PCR, and sequencing analysis, we also performed liposome-mediated transfection of vascular endothelial cells of in vitro cultivation, and detected the expression of fusion protein pEGFP/hVEGF165 using fluorescence microscope, RT-PCR, and Western blot., Results: Both gene VEGF165 and multiple clone site of pEGFP-N1 confirmed by PCR, enzyme digestion, and sequence analysis. EGFP/VEGF protein was expressed in vascular endothelial cells after pEGFP/VEGF165 recombinant plasmid transfected vascular endothelial cells., Conclusion: Fusion protein eukaryotic plasmid of report gene EGFP and VEGF165 is successfully constructed, and EGFP/VEGF can be expressed in vascular endothelial cells, which lays a foundation for the application of VEGF gene in treating ischemia vascular diseases.

Objective: To observe the effect of ranitidine on gastric acid, plasma endothelin, and calcitonin gene-related peptide (CGRP) in patients undergoing the brain operation, and to explore the possible pathogenesis of ranitidine on preventing from gastric mucosal injury under the stress., Methods: Thirty patients who underwent brain surgery were randomly divided into 2 groups: Fifteen patients in the control group did not use ranitidine and the other 15 in the treatment group received ranitidine 150 mg intravenously twice daily besides the routine therapy. We continuously monitored the gastric pH value from 4 hours pre-operatively to 72 hours post-operatively in the 30 patients. We also determined the plasma endothelin and CGRP levels of the patients at the 4th hour pre-operatively and at the 4th, 24th, and 72nd hours post-operatively., Results: In the control group there was no significant difference between the mean intra-gastric pH values pre-operatively and post-operatively (P> 0.05). In the treatment group the level of intra-gastric pH was much higher than that in the control group (P< 0.05). In the control group, the level of plasma endothelin significantly higher and the level of calcitonin gene-related peptide significantly lower than that pre-operatively (P< 0.01), but the level of plasma endothelin significantly was lower and the level of calcitonin gene-related peptide obviously higher in the post-operative treatment group than that pre-operatively (P< 0.01)., Conclusion: The brain operation obviously influences the endogenous plasma endothelin and CGRP levels, but its influence on the intra-gastric acid is not visible. Ranitidine can obviously decrease the level of intra-gastric acid, and improve the macrocirculation of gastric mucous membrane by decreasing ET and increasing the CGRP level.