Alpha- and beta-adrenergic blocking agents and imipramine inhibit the increased hyaluronate synthesis that may be induced in human synovial cultures by connective tissue activating peptide (CTAP). Considerations of drug concentration requirements, actions of analogues, and time studies all indicate that the adrenergic blockers do not act in this circumstance as conventional blockers of alpha or beta receptor sites. It is suggested that the membrane-stabilizing properties of these agents may be the important determinant for their limited "antiactivation" effect. Ethacrynic acid, a potent and more complete inhibitor of connective tissue activation, appears to act via a different mechanism.

Alprenolol↗

PubMedDate not supplied

Frequency of neoplasia in systemic lupus erythematosus and rheumatoid arthritis.

A patient population admitted to the hospital for either SLE or RA was surveyed for the subsequent development of neoplasms. The frequency of neoplasm in SLE patients appeared to be exaggerated, whereas the frequency of subsequent neoplasm in rheumatoid patients was unexpectedly low. A paucity of nephritis in the SLE group was noted. Further reports are encouraged so that the magnitude of the risk of malignancy developing with immunosuppressive therapy can be more precisely ascertained.

Adult↗

PubMedDate not supplied

Fibronectin in rheumatoid and non-rheumatoid arthritic synovial fluids and in synovial fluid cryoproteins.

Concentrations of fibronectin, immunoglobulins G, M, and A, and C3 and C4 components of complement, and other plasma proteins were determined in synovial fluids from patients with rheumatoid arthritis (RA) and other diseases (non-RA). Fibronectin concentrations were two to three times greater in all synovial fluids than in plasma, and RA synovial fluids had a significantly higher mean concentration than non-RA fluids (883 microgram per ml vs. 588 microgram per ml, respectively, p less than 0.01). The mean concentrations of other synovial fluid constituents were less than their mean plasma concentrations. These results suggest that unlike other plasma constituents, either plasma fibronectin is concentrated in synovial fluids or that a substantial portion of synovial fluid fibronectin may be derived from synovial tissue cells. Both the C3 and C4 complement components were present in lower concentrations in RA than in non-RA synovial fluids. The C3 contents showed a statistically significant negative correlation with the fibronectin contents. Fibronectin was also found in all synovial fluid cryoprotein fractions tested, although its content varied greatly as a percent of the total cryoprotein protein (0.01 to 43 percent). The data show that fibronectin is a consistent constituent of synovial fluid cryoproteins in agreement with our previously reported finding that fibronectin is found in all serum cryoglobulin fraction tested.

Arthritis↗

PubMedDate not supplied

Connective tissue activation XIX. Plasma levels of the CTAP-III platelet antigen in rheumatoid arthritis.

Plasma levels of platelet granule proteins CTAP-III and beta-thromboglobulin (beta-TG) were measured by radioimmunoassay of their common antigen (CTAP-Ag). Healthy adults had 29.4 +r5.8 ng CTAP-Ag/ml plasma while patients with rheumatoid arthritis (RA) had higher levels of the CTAP-Ag (range 23-260 ng/ml, median 43 ng/ml, p less than .006). RA patients with CTAP-Ag levels greater than 50 ng/ml (mean 104.8 ng/ml) were compared to patients having lower CTAP-Ag levels. Patients in the group with elevated plasma CTAP-Ag levels had higher sedimentation rates (p less than .005), and higher platelet counts (p less than .05). Anemia was more common in patients with abnormal CTAP-Ag levels.

Antigens↗