1. Free Radicals in Medicine. II. Involvement in Human Disease*
PETER A. SOUTHORN, M.B., B.S., GARTH POWIS, D.Phil. 
Mayo Clinic Proceedings 
Volume 63, Issue 4, Pages (April 1988)
DOI: /S (12)
Copyright © 1988 Mayo Foundation for Medical Education and Research Terms and Conditions

2. Fig. 1
Myeloperoxidase (MPO)-hydrogen peroxide-halide bactericidal activity of neutrophils. NADP+ and NADPH = oxidized and reduced forms of nicotinamide-adenine dinucleotide phosphate.
(Modified from Fantone and Ward.3 By permission of the American Association of Pathologists.)
Mayo Clinic Proceedings  , DOI: ( /S (12) )
Copyright © 1988 Mayo Foundation for Medical Education and Research Terms and Conditions

3. Fig. 2
Diagrammatic representation of morphologic changes that occur in pulmonary oxygen toxicity.
Mayo Clinic Proceedings  , DOI: ( /S (12) )
Copyright © 1988 Mayo Foundation for Medical Education and Research Terms and Conditions

4. Fig. 3
Two hypotheses to explain recruitment of neutrophils into lungs exposed to hyperoxia and their involvement in the resultant lung injury. A, Neutrophils recruited to lungs because of release of chemotaxins by hyperoxia-damaged macrophages. B, Neutrophils recognize and adhere to hyperoxia-damaged lung endothelial cells.
Mayo Clinic Proceedings  , DOI: ( /S (12) )
Copyright © 1988 Mayo Foundation for Medical Education and Research Terms and Conditions

5. Fig. 4
Possible mechanism for formation of oxygen free radicals during ischemic reperfusion. During ischemia, adenosine triphosphate (ATP) is catabolized to the substrate hypoxanthine, and the enzyme xanthine dehydrogenase is converted to xanthine oxidase by a protease activated by increased free calcium. On reperfusion, hypoxanthine reacts with molecular oxygen in presence of xanthine oxidase to form superoxide anion radicals (O2). In the presence of iron salts, superoxide anion radicals can form hydroxyl radicals.
(Modified from McCord and Roy.103 By permission of the National Research Council of Canada.)
Mayo Clinic Proceedings  , DOI: ( /S (12) )
Copyright © 1988 Mayo Foundation for Medical Education and Research Terms and Conditions