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 Clinical significance of xanthine derivatives. Derivatives of xanthine, known collectively as xanthines, are a group of alkaloids commonly used for their effects as mild stimulants and as bronchodilators, notably in treating the symptoms of asthma. — “Xanthine - Wikipedia, the free encyclopedia”, en.wikipedia.org
Xanthine oxidase (XO (sometimes 'XAO'), a form of xanthine oxidoreductase that generates reactive oxygen species) is an enzyme that catalyzes the oxidation of hypoxanthine to xanthine and can further catalyze the oxidation of xanthine to uric acid. — “Xanthine oxidase - Wikipedia, the free encyclopedia”, en.wikipedia.org
Xanthine dehydrogenase belongs to the group of molybdenum-containing hydroxylases involved in the oxidative metabolism of purines. Xanthine dehydrogenase can be converted to xanthine oxidase by reversible sulfhydryl oxidation or by irreversible proteolytic modification.. — “Xanthine dehydrogenase - Wikipedia, the free encyclopedia”, en.wikipedia.org