They detected glycated, oxidized, and nitrated proteins and amino acids in the synovial fluid and plasma of arthritic patients with characteristic patterns found in early and advanced OA and rheumatoid arthritis (RA), and non-RA, with respect to healthy controls. They developed two algorithms for consecutive use in diagnosis, and found that sensitivities/specificities were: good skeletal health, 0.92/0.91; early-stage OA, 0.92/0.90; early-stage RA, 0.80/0.78; and non-RA, 0.70/0.65. They noted that damaged amino acids increased further in participants with severe and advanced OA and RA. Learn more...