Biomedical subjects

J R Fraser

Publications and source records attributed to J R Fraser.

At least 127 records · Page 7Linked to original sources

PubMed1977

Lysosomal activation by neutral saccharides in cell cultures of synovium.

On exposure to sucrose or neutral polysaccharides, cell cultures from human synovium showed cytoplasmic vacuolation, increased numbers of lysosomes, and ultrastructural changes simulating those described in rheumatoid synovial intima and similarly treated embryonic caritlage and bone. These changes were accompanied by raised intracellular lysosomal enzyme activity without corresponding increases in the extracellular level of these enzymes. Structural changes and enzymic responses were less intense during exposure to the neutral polysaccharides. The secretion of large polymers of hyaluronic acid was consistently decreased during sucrose treatment. Evidence of heightened hyaluronidase-like activity was found in cellular extracts of sucrose-treated cultures, but not in the culture medium.

Acetylglucosaminidase↗

PubMed1977

Rheumatoid synovial cells from intact joints. Morphology, growth, and polykaryocytosis.

Synovial cell lines were isolated by instillation of trypsin or chymotrypsin into intact knee joints of patients with persistent rheumatoid effusions resistant to conventional therapy. Morphology and growth in the primary phase were compared with rheumatoid cells isolated from excised synovium and nonrheumatoid synovial cells obtained from intact joints of cadavers or amputated limbs. Cell populations from all sources included varying proportions of macrophage-like and fibroblast-like cells, with only 1-3% multinucleated cells. In medium supplemented with calf serum alone, rheumatoid cells from intact joints showed negligible changes in morphology. However, in the presence of nonrheumatoid, autologous rheumatoid or homologous rheumatoid serum a rapid increase occurred in size of the macrophage-like cells and numbers of polykaryocytes, including some giant syncytial cells. These effects were directly proportional to serum concentration and were identical in fresh or heat-inactivated serum. In most of these rheumatoid cell lines no multiplication occurred, regardless of serum type or concentration. In rheumatoid synovial cells from excised synovium, human serum induced both polykaryocytosis and rapid growth of fibroblasts. Nonrheumatoid synovial cells grew rapidly but few polykaryocytes developed, mostly with less than 6 nuclei. Evidence of viral infection in rheumatoid synovial cells was sought by electron microscopy after stimulation of polykaryocytosis by human serum. In one of the cultures many cells were found with intranuclear particles possessing characteristics of the adenovirus group.

Arthritis, Rheumatoid↗

PubMed1977

Proteins retained with hyaluronic acid during ultrafiltration of synovial fluid.

The identity of the proteins associated with hyaluronic acid after ultrafiltration of bovine synovial fluid was examined. With discontinuous filtration, alpha2 macro- and IgM globulins were retained in hyaluronic complex both from synovial fluid and from a similar mixture of hyaluronic acid and serum. With continuous filtration and stirring to prevent formation of gels, protein was retained with hyaluronic acid in similar proportions. This protein showed immunologic identity with serum albumin, but differed in amino acid composition. After comparison with results of gel filtration, it was concluded that the identity of the retained proteins can be determined by the concentration of hyaluronic acid without variation in other ionic conditions.

Albumins↗

PubMed1975

Epidemic polyarthritis: a cytological, virological and immunochemical study.

A patient with epidemic polyarthritis was studied within 48 hours of onset when specific serum antibodies were still low. The synovial fluid showed a fall in hyaluronic acid level and rise in protein levels though the immune globulins, and especially IgM, rose to a lesser degree and remained well below the levels in the serum. Attempts to grow virus from synovial fluid or blood lymphocytes failed despite the use of several new techniques. The complement components C'3 and C'4 were not depleted in serum or synovial fluid. The synovial fluid was devoid of neutrophil leucocytes, and contained predominantly monocytes and macrophages which were remarkable for mitotic and for enhanced and indiscriminate phagocytic activity. From this and other evidence, an explanation is proposed for the cytological response and difficulties in recovering infective virions in virus-induced arthritis. No virus antigen was detected in the supernatant synovial fluid and electron microscopy showed virus-like particles only in cytolysosomes.

Adult↗

PubMed1974