Helicobacter pylori in Pediatric Patients.

Helicobacter pylori causes one of the most common chronic bacterial infections. Clinical manifestations include asymptomatic chronic gastritis, gastric and duodenal ulcers, adenocarcinoma, and gastric mucosa-associated lymphoid tissue lymphoma in adults. In children, most H pylori infections are asymptomatic despite being associated with microscopic gastric inflammation, and children rarely develop complications associated with infection. Due to rising resistance and lack of symptomatic improvement in the absence of peptic ulcer disease, testing and eradication therapy are recommended only for the subset of patients in whom there is a high suspicion of peptic ulcer disease. Studies do not support the role of H pylori infection in functional disorders such as recurrent abdominal pain. A variety of diagnostic modalities exist; therefore, it is important to understand the appropriate approach to diagnosing H pylori infection. The joint European Society for Pediatric Gastroenterology, Hepatology, and Nutrition/North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition guidelines were updated in 2016. Antibiotic and proton pump inhibitor weight-based dosing guidelines have changed to prevent ineffective treatment from increasing antimicrobial resistance. Treatment can also be guided by antibiotic sensitivities obtained from H pylori culture. Patients should be tested again after treatment to confirm eradication.

Conjugated linoleic acid is a preferential substrate for fatty acid nitration.

The oxidation and nitration of unsaturated fatty acids by oxides of nitrogen yield electrophilic derivatives that can modulate protein function via post-translational protein modifications. The biological mechanisms accounting for fatty acid nitration and the specific structural characteristics of products remain to be defined. Herein, conjugated linoleic acid (CLA) is identified as the primary endogenous substrate for fatty acid nitration in vitro and in vivo, yielding up to 10(5) greater extent of nitration products as compared with bis-allylic linoleic acid. Multiple enzymatic and cellular mechanisms account for CLA nitration, including reactions catalyzed by mitochondria, activated macrophages, and gastric acidification. Nitroalkene derivatives of CLA and their metabolites are detected in the plasma of healthy humans and are increased in tissues undergoing episodes of ischemia reperfusion. Dietary CLA and nitrite supplementation in rodents elevates NO(2)-CLA levels in plasma, urine, and tissues, which in turn induces heme oxygenase-1 (HO-1) expression in the colonic epithelium. These results affirm that metabolic and inflammatory reactions yield electrophilic products that can modulate adaptive cell signaling mechanisms.