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Biomedical subjects

R A Turner

Publications and source records attributed to R A Turner.

81 records · Page 5Linked to original sources

Phospholipase activity in synovial fluid from patients with rheumatoid arthritis, osteoarthritis and crystal-associated arthritis.

Phospholipase activity was assayed in cell-free synovial fluid (SF) from patients with rheumatoid arthritis (RA, n = 28), osteoarthritis (OA, n = 10), and crystal-associated arthritis (C, n = 7) by measuring the release of either [14C]oleic acid or [3H]arachidonic acid from radiolabeled E. coli phospholipids. Activity measured by oleic acid release was not significantly different between the three groups of patients (RA = 571 +/- 43.3, OA = 460 +/- 54.7 and C = 718 +/- 162.6 pmol/min/mg). Arachidonic acid release was significantly (p less than 0.005) less in OA (31 +/- 7.3) than RA (61 +/- 4.7) which was similar to C (58 +/- 17.6 pmol/min/mg). Arachidonic acid release correlated significantly with the SF white blood cell count (r = 0.483, p less than 0.01). This study shows the importance of the type of substrate used to measure phospholipase activity and indicates that differences in the capacity to release arachidonic acid may exist between RA and OA disease states.

Arachidonic Acid↗

Clinical evaluation of radiographic progression in rheumatoid arthritis.

Four rheumatologists and 2 radiologists utilized 3 reading techniques to evaluate clinical radiographic progression in selected serial hand and wrist films from 5 rheumatoid arthritis patients. The carpometacarpal radio determinations were the most internally consistent; global assessment and total erosion + joint space narrowing scores showed the best between-method correlations; and the erosion + joint space narrowing scores depicted most sensitively the progression over time which was not affected by immunomodulating agent or non-steroidal anti-inflammatory agent therapy. In this study, instructed, non-experienced readers detected rheumatoid radiographic progression utilizing readily available scoring techniques.

Arthritis, Rheumatoid↗

Alterations in arachidonic acid metabolism and chemotactic response in polymorphonuclear leukocytes from patients with rheumatoid arthritis.

This study examines the interrelationship between arachidonic acid (AA) metabolism and chemotactic potential of human peripheral blood neutrophils from both normal donors and patients with rheumatoid arthritis (RA). We demonstrate that there is a significant inverse relationship between the neutrophil's metabolic capability to produce [3H]LTB4 in response to ionophore A23187 stimulation versus the cell's chemotactic potential to optimal concentrations (i.e., 20 nM) of the chemotactic peptide f-Met-Leu-Phe as determined by leading front (r = 0.567, p = 0.009), mean depth (r = 0.458, p = 0.042), and population ratio (r = 0.471, p = 0.036) analyses. Subsequent Percoll density gradient studies revealed several RA neutrophil subpopulations exhibiting significantly enhanced (p less than 0.05) [3H] AA metabolism over corresponding density normal cells. Based on these results, we speculate that RA peripheral blood neutrophils have been "processed" to become less chemotactically-responsive yet more metabolically-active cells, and that the increased ability to produce LTB4 through both increased phospholipase A2 and lipoxygenase activities are part of the increased metabolic capabilities of the cell.

Arachidonic Acid↗

Decreased production of suppressive-B-cell factor by synovial membrane B-lymphocytes in rheumatoid arthritis.

Suppressive-B-cell factor (SBF) is an autoregulatory B-cell lymphokine produced by heat-aggregated-IgG stimulated B-lymphocytes which suppresses polyclonal immunoglobulin production. SBF production by rheumatoid arthritis (RA) patients' peripheral blood B-lymphocytes inversely correlates with disease activity and in vitro rheumatoid factor production. To further define the role of SBF in the pathogenesis of RA, the present study measured SBF production by surgically-obtained synovial membrane mononuclear leukocytes. SBF production by RA synovial leukocytes was similar to the levels previously described for RA peripheral blood leukocytes. Both RA and osteoarthritis (OA) synovial leukocytes produced significantly less SBF than leukocytes obtained from otherwise healthy patients with plica. OA patients produced less SBF than RA patients, but the difference was not statistically significant. SBF values for combined RA patients and controls with OA or plica correlated with the degree of histological plasma cell infiltration providing further evidence for SBF production by cells of the B-lymphocyte lineage. Depletion studies also demonstrated that synovial SBF was produced by B-lymphocytes. The molecular weight (34,000) of synovial SBF was similar to the molecular weight of peripheral blood SBF. Decreased SBF production by RA synovial B-lymphocytes is a functional abnormality in RA which may contribute to the perpetuation of synovial rheumatoid factor production and chronic synovial inflammation.

Adult↗

Psycho-social adjustment of rheumatoid arthritis patients from two alternative treatment settings.

Fifty rheumatoid arthritis (RA) patients are compared with a control sample of 72 non-patients on five attitude scales which measure psychol-social adjustment. Patients generally indicate more negative attitudes toward self, which are significantly related to variables such as severity of condition and socio-economic status. The adjustment of patients who are being treated by registered nurses (physician extenders) is not significantly different from that of patients who are being treated by physicians.

Adaptation, Psychological↗

Polymorphonuclear leukocyte secretory and metabolic responses to immunoglobulin aggregates.

Biologic activities of soluble immunoglobulin G (IgG) aggregates, insoluble IgG aggregates and precipitates resulting from addition of serum containing rheumatoid factor (RF) to soluble or insoluble IgG aggregates were examined in terms of lysosomal enzyme release and/or stimulation of the hexose monophosphate pathway (HMP) in human polymorphonuclear leukocytes (PMN). Granular enzyme release and HMP stimulation were consistently greater for insoluble aggregates and complexes than for soluble aggregates and controls. One role of IgM rheumatoid factor may be its ability to convert relatively inactive soluble IgG aggregates into insoluble IgG-RF complexes capable of stimulating selective release of PMN lysosomal enzymes.

Glucuronidase↗

Inhibition of neutrophil phagocytosis and enzyme release by hyaluronic acid.

Hyaluronic acid at a concentration found in normal joints (4 mg/ml) inhibited the uptake of aggregated IgG by human peripheral blood polymorphonuclear leukocytes, but concentrations of hyaluronic acid found in inflammatory joints (1 mg/ml) did not. Similarly, hyaluronic acid at 4 mg/ml, but not 1 mg/ml, inhibited the release of lysozyme from aggregated IgG stimulated polymorphonuclear leukocytes. beta-Glucuronidase release was inhibited by both concentrations of hyaluronic acid. Physiological concentrations of hyaluronic acid inhibit this model system for the fluid phase of rheumatoid arthritis and hyaluronic acid may be an important immunomodulating substance in the rheumatoid joint.

Cell Adhesion↗

Ocular pathology, tear production, and tear lysozyme in rheumatoid arthritis.

Ninety-seven rheumatoid arthritis (RA) patients receiving investigational nonsteroidal antiinflammatory drugs were found to have a 31.9% prevalence and 24.5%/year incidence of ocular pathology. None of these ocular lesions were definitely related to their RA or drug therapy. Twenty-one of these patients were studied further for evidence of keratoconjunctivitis sicca. None of these patients had abnormal rose bengal staining, but over half had decreased tear production on both stimulated and unstimulated Schirmer's testing and many patients had high tear lysozyme levels. Increased tear lysozyme levels and decreased Schirmer's tests correlated with a modified rheumatoid activity index.

Adult↗