Mesalazine Has No Effect on Mucosal Immune Biomarkers in Patients with Diarrhea-Dominant Irritable Bowel Syndrome Referred to Shariati Hospital: A Randomized Double-Blind, Placebo-Controlled Trial.

BACKGROUND Intestinal mast cells may cause gastrointestinal symptoms in patients with diarrhea-dominant irritable bowel syndrome (IBS). The objective of this study was to determine the effect of mesalazine on the number of lamina propria mast cells and clinical manifestations of patients with diarrhea-dominant IBS referred to Shariati Hospital affiliated to Tehran University of Medical Sciences. METHODS This was a randomized placebo-controlled double-blind trial conducted on 49 patients with diarrhea-dominant IBS. The patients were randomly assigned to one of the experiment or control groups. The patients in experiment group took 2400 mg mesalazine daily in three divided doses for 8 weeks and the patient in control group took placebo on the same basis. Our first targeted outcome was an assigned downturn of mast cells number to the safe colonic baseline and the next one was a marked palliation of disease symptoms. Data were analyzed conforming intention-to-treat method. We used MANCOVA test to compare our both assigned outcomes in the two groups. We also compared the data with baseline values in both groups.All statistical tests were performed at the significance level of 0.05. RESULTS There was no significant difference between Mesalazine and placebo groups regarding the number of mast cells (p value=0.396), abdominal pain (p value=0.054), bloating (p value=0.365), defecation urgency (p value=0.212), and defecation frequency (p value=0.702). CONCLUSION Mesalazine had no significant effect either on the number of mast cells or on the severity of disease symptoms. This finding seems to be inconsistent with the hypothesis indicating immune mechanisms as potential therapeutic targets in IBS. The possible difference in this effect of Mesalazine should be evaluated in further studies among populations varying in race, ethnic, and geographical characteristics.

Prevalence of gastric precancerous lesions among chronic dyspeptic patients and related common risk factors.

Gastric cancer is one of the leading causes of cancer-related deaths worldwide. Progression of gastric cancer follows several steps from gastritis to atrophy, intestinal metaplasia, dysplasia, and finally cancer. The aim of this study was to determine the prevalence of gastric precancerous lesions and related common risk factors in a group of chronic dyspeptic patients. A total of 688 chronic dyspeptic patients older than 40 years of age were consecutively enrolled. The exclusion criteria were pregnancy, and a history of gastric cancer and gastric surgery. A questionnaire including demographic and clinical data, smoking habits, alcohol use, NSAIDs, and regular aspirin use was completed for all patients. Upper endoscopy and gastric biopsy were performed for all of the participants according to the standard protocols. Upper endoscopy was performed for all of the participants and biopsies were taken according to the biopsy protocol. The specimens were examined in a blinded manner by two expert gastrointestinal pathologists. The mean age of the participants was 57.87±9.10 years; there were 361 (52.5%) women. The prevalence of intestinal metaplasia, gastric atrophy, dysplasia, and positive Helicobacter pylori infection was 19.8, 12.8, 3.2%, and 64.5%, respectively. Age and H. pylori infection showed a significant association with pathological findings (odds ratio=3.10, 95% confidence interval: 1.91-4.72 and odds ratio=3.56, 95% confidence interval: 2.30-5.53, respectively). According to the high prevalence of precancerous lesions in patients with chronic dyspepsia who were older than 40 years of age, upper endoscopy and gastric mapping sampling for the detection of these lesions is recommended in intermediate-risk to high-risk areas.

Temperature changes during and after eccentric contractions and its effect on force and desmin loss in rat.

The typical features of eccentric exercise-induced muscle damage is prolonged loss of muscle strength and the most rapid structural change in the fibers is loss of immunostaining for the intermediate filament protein, desmin. In this study isolated perfused rat muscle was used to examine the direct effect of temperature changes on the eccentric contraction-induced force and desmin loss. The left medial gastrocnemius muscle was separated and the entire lower limb was transferred into a prewarmed (35°C) organ bath. Temperature was adjusted to 31 or 39°C during and after eccentric contractions. Maximal isometric force and desmin loss were measured after 15 isometric or eccentric contractions. According to our data, organ bath temperature changes during or after eccentric contractions had no significant effect on force loss. However, a strong correlation between desmin loss and temperature changes during (r = 0.886, P< 0.05) and a weak correlation between desmin loss and temperature changes after (r= 0.699, P<0.05) eccentric contractions was observed. Our results suggest that cooling during eccentric contractions may decrease desmin loss but temperature changes after eccentric contractions have no effect on desmin loss.