Clinical characteristics and risk factors of gastroesophageal reflux disease in Vietnamese patients with upper gastrointestinal symptoms undergoing esophagogastroduodenoscopy.

BACKGROUND AND AIM: The risk factors associated with the increase in prevalence of gastroesophageal reflux disease (GERD) are not consistent across countries and there have been few studies in Asia in the past 10 years. This study was conducted to assess the features and risk factors of GERD in Vietnamese patients. METHODS: A cross-sectional study was conducted on 1947 out-patients ≥18 years of age who were presented with upper gastrointestinal symptoms and underwent esophagogastroduodenoscopy. Reflux esophagitis was graded according to the Los Angeles classification. Endoscopically suspected Barrett's esophagus (BE) was recorded according to the Prague C and M criteria and biopsy was taken for histologic examination. RESULTS: There were 511 (26.2%) patients with GERD, 242 (47.4%) with nonerosive reflux disease, and 269 (52.6%) with reflux esophagitis and/or BE. Epigastric pain, regurgitation, and heartburn were the chief complaints in 36.8%, 27.0%, and 9.2% of patients, respectively. Most of the patients with mucosal injury had reflux esophagitis in mild grade and BE in the form of C0M ≤2 (99.6%, 231/232 and 97.8%, 46/47, respectively). In multivariate analysis, hiatal hernia, male gender, waist-to-hip ratio (independent from general obesity), and smoking were risk factors for GERD while Helicobacter pylori infection was negatively associated with GERD. CONCLUSIONS: The majority of GERD patients had none or mild mucosal injury. Typical reflux symptoms, however, may not be the chief complaints. Central obesity would be more important than general obesity as a risk factor, while H. pylori infection was a "protective" factor for GERD in Vietnamese patients.

Iodine-mediated formal [3 + 2] annulation for synthesis of furocoumarin from oxime esters.

A novel synthesis of furocoumarins was developed by a reaction between oxime esters and 4-hydroxycoumarins. The reaction was proposed to undergo radical mechanism mediated by iodine, a cheap and common laboratory reagent. Mechanistic studies showed the key for the successful transformation was the presence of α-iodoimine intermediate which facilitated the ring-closing step. The developed conditions produced good functional group tolerance with a wide range of high-profile furocoumarin product. The potential for this strategy to be applied in other syntheses of heterocyclic compounds is highly achievable.

Prevalence, clinical characteristics, and risk factors of Barrett esophagus in Vietnamese patients with upper gastrointestinal symptoms.

The current barrier for investigation of Barrett esophagus (BE) in Asia is diagnostic standardization, which is a challenge to identify its true risk factors. This study aimed to investigate the prevalence, clinical characteristics and risk factors of BE in Vietnamese patients with upper gastrointestinal symptoms.A cross-sectional study was conducted on consecutive outpatients who underwent upper gastrointestinal endoscopy. Endoscopically suspected esophageal metaplasia (ESEM) which was clearly visible at least 1 cm above the gastroesophageal junction at endoscopy was taken biopsy. At least 1 biopsy per 2 cm in tongues of ESEM and 4 biopsies per 2 cm of circumferential ESEM were taken. The diagnostic criterion for BE was replacement of the normal squamous epithelial lining by columnar epithelium confirmed by histology.A total of 1947 patients were recruited. Forty-seven out of 58 patients with ESEM were histologically confirmed BE. The prevalences of BE and hiatal hernia (HH) were 2.4% (95% confidence interval [CI], 1.7-3.1%) and 2.3% (95% CI, 1.6-2.9%), respectively. Heartburn and/or regurgitation presented in only 61.7% (95% CI, 46.4-75.5%) of patients with BE. In multivariate analysis, the only 2 factors significantly associated with BE were HH (OR 7.53; 95% CI, 3.13-18.11; P < .001) and typical reflux symptom (OR 2.07; 95% CI, 1.12-3.83; P = .020).BE is not uncommon in Vietnamese patients with upper gastrointestinal symptoms. In addition, typical reflux symptoms and HH are the risk factors for BE in Vietnamese.

Perceived racial discrimination, but not mistrust of medical researchers, predicts the heat pain tolerance of African Americans with symptomatic knee osteoarthritis.

OBJECTIVE: Studies have shown that perceived racial discrimination is a significant predictor of clinical pain severity among African Americans. It remains unknown whether perceived racial discrimination also alters the nociceptive processing of painful stimuli, which, in turn, could influence clinical pain severity. This study examined associations between perceived racial discrimination and responses to noxious thermal stimuli among African Americans and non-Hispanic Whites. Mistrust of medical researchers was also assessed given its potential to affect responses to the noxious stimuli. METHOD: One-hundred and 30 (52% African American, 48% non-Hispanic White) community-dwelling older adults with symptomatic knee osteoarthritis completed two study sessions. In session one, individuals provided demographic, socioeconomic, physical and mental health information. They completed questionnaires related to perceived lifetime frequency of racial discrimination and mistrust of medical researchers. In session two, individuals underwent a series of controlled thermal stimulation procedures to assess heat pain sensitivity, particularly heat pain tolerance. RESULTS: African Americans were more sensitive to heat pain and reported greater perceived racial discrimination as well as greater mistrust of medical researchers compared with non-Hispanic Whites. Greater perceived racial discrimination significantly predicted lower heat pain tolerance for African Americans but not non-Hispanic Whites. Mistrust of medical researchers did not significantly predict heat pain tolerance for either racial group. CONCLUSION: These results lend support to the idea that perceived racial discrimination may influence the clinical pain severity of African Americans via the nociceptive processing of painful stimuli.