OBJECTIVE To investigate whether soluble interleukin-2 receptor (sIL-2R) could be a useful marker of disease activity in rheumatoid arthritis (RA); sIL-2R levels in serum and in synovial fluid were determined by enzyme-linked immunosorbent assay. METHODS Sixty five serum and 27 synovial fluid samples were obtained from patients with RA. Twenty five serum and 28 synovial fluid samples from pat...

The penetration of gentamicin and tobramycin into the synovial fluid of 12 patients with nontraumatic joint effusions was studied. Simultaneous serum and synovial fluid specimens taken after the intramuscular or intravenous administration of an antimicrobial agent were assayed. Synovial fluid levels of antibiotic were >50% of serum levels in all subjects studied. In five patients, synovial flui...

It was recently reported (Niedermeier, Creitz, and Holley, 1962) that the copper concentration in synovial fluid from patients with rheumatoid arthritis was elevated by a factor of three. The observation that copper could not be dialysed out of either "normal" or rheumatoid synovial fluid led to speculation concerning the nature of the compounds with which this element was associated. It was sh...

Articular cartilage is composed of cells surrounded by a matrix of protein-chondroitin sulphate complex. It is nourished by diffusion from the synovial fluid. It is probable that synovial fluid is a dialysate of plasma, to which another mucopolysaccharide-protein complex containing hyaluronic acid-has been added by synovial cells. Synovial fluid does not contain fibrinogen (Ropes and Bauer 1953...

Synovial fluid is a viscous solution found in the cavities of synovial joints. The principal role of synovial fluid is to reduce friction between the articular cartilages of synovial joints during movement. The presence of high molar mass hyaluronan (HA) in this fluid gives it the required viscosity for its function as lubricant solution. Inflammation oxidation stress enhances normal degradatio...

Synovial fluid leucocyte counts greater than 50 000 cells/mm3 (50 X 10(9)/1) are usually associated with infectious arthritis. Six children, 3 of whom meet the criteria for juvenile rheumatoid arthritis (JRA), are described with synovial fluid white blood cell counts greater than 88 000 cells/mm3 (88 X 10(9)/1). Two had synovial fluid leucocyte counts greater than 100 000 cells/mm3 (100 X 10(9)...

Proteoglycans are molecules that are degraded and released from the articular cartilage into the synovial fluid early in an arthritic process. Such released proteoglycans were quantified by an enzyme linked immunosorbent assay (ELISA). The proteoglycan content in synovial fluid from patients with various knee joint arthritides was constant in two samples withdrawn five days apart. To determine ...

Cartilage glycosaminoglycans (GAGs) were measured by a spectrophotometric assay in synovial fluid obtained from 30 normal bovine hock joints and 15 osteoarthritic human knee joints. Results were compared with those obtained by radioimmunoassay (RIA). The spectrophotometric method (dimethylmethylene blue (DMB) assay) was found to be simple, safe, and sufficiently reproducible to be of potential ...

The concentrations of five normally occurring protease inhibitors in serum and synovial fluid were compared in patients with rheumatoid arthritis, osteoarthrosis, and normal controls. The patients with rheumatoid arthritis showed a significant rise in alpha1-antitrypsin, alpha1-antichymotrypsin, and inter-alpha-trypsin inhibitor (in decreasing order) in serum as well as in synovial fluid. In sy...

Evidence has been shown that pathological synovial fluid contained a substance capable of stabilizing rat liver lysosomes which was partly inactivated by treatment with trypsin and by storage. Such synovial fluid also appeared to contain a substance which labilized lysosomes and which was more stable than the stabilizing substance. (2) The lysosomal stabilizing substance described above was non...