Canker sore. In some cases, the exact cause of a canker sore is unknown, but trauma or injury to the mouth or oral soft tissues may be the culprit. Other possible causes are food sensitivities, spicy, salty or acidic foods, vitamin B deficiency, hormonal shifts and stress. Cold sore.
What does xoxo mean? Hugs and kisses or xoxo is a term used for expressing affection or good friendship at the end of a written letter, email or SMS text message.
Xanthine oxidase (XO, sometimes 'XAO') is a form of xanthine oxidoreductase, a type of enzyme that generates reactive oxygen species.These enzymes catalyze the oxidation of hypoxanthine to xanthine and can further catalyze the oxidation of xanthine to uric acid.anthine oxidase is a superoxide-producing enzyme found normally in serum and the lungs, and its activity is increased during influenza A infection. During severe liver damage, xanthine oxidase is released into the blood, so a blood assay for XO is a way to determine if liver damage has happened.