ABSTRACT
This work, directed to characterization of proteoglycans present in normal human synovial fluid by Western blotting techniques, revealed an intimate relationship of these proteoglycans to those of articular cartilage. Analyses were performed on samples subjected to digestion with chondroitinase ABC, in the presence or absence of keratanase, yielding products containing core proteins with glycosaminoglycan side chain stubs. The proteoglycan core proteins contained epitopes reactive with monoclonal antibodies that distinguish between chondroitin sulfate-4 and chondroitin sulfate-6. Additionally, these products reacted with monoclonal antibody to keratan sulfate when keratanase was omitted from the digestion. The analysis of synovial fluid revealed that the proteoglycan core proteins expressed predominantly the chondroitin sulfate-6 epitope, with expression of the chondroitin sulfate-4 epitope demonstrable only in prepubertal individuals. There was coexpression of both chondroitin sulfate epitopes in all proteoglycan core proteins of prepubertal individuals. Coexpression of chondroitin sulfate and keratan sulfate epitopes occurred in all proteoglycan core proteins. Proteoglycan core proteins had M(r) similar to those obtained from articular cartilage. Hence, in individuals free of joint disease, most proteoglycans seem to be transferred from articular cartilage to the synovial fluid without major alteration in the apparent size of the proteoglycan core protein. Only a minor set of proteoglycan core proteins had no direct articular cartilage equivalent. As this set also contained keratan sulfate, it is likely to be of articular cartilage origin, but probably modified by proteolysis.
Subject(s)
Cartilage, Articular/chemistry , Extracellular Matrix Proteins , Glycoproteins/analysis , Proteoglycans/analysis , Synovial Fluid/chemistry , Adolescent , Adult , Aggrecans , Blotting, Western , Child , Child, Preschool , Chondroitin Sulfates/immunology , Electrophoresis, Polyacrylamide Gel , Epitopes/analysis , Glycoproteins/immunology , Humans , Infant , Lectins, C-TypeABSTRACT
The early biochemical events that link interleukin-1 (IL-1) receptor occupancy to neutral proteinase production in synovial cells were studied. Addition of human r-IL-1 to human synovial cells in culture stimulated phospholipase A2 (PLA2) activity, inositol triphosphate production and plasminogen activator (PA) activity in a dose dependent manner with similar EC50 values (0.1-0.5 nM). These results, coupled with time courses and other studies, suggest that the IL-1 modulation of PA involves both products of PLA2 and phospholipase C (PLC) activation. On the other hand, the IL-1 induction of collagenase may primarily involve PLC and protein kinase C activation.
Subject(s)
Interleukin-1/physiology , Signal Transduction , Synovial Membrane/physiology , Arthritis, Rheumatoid/physiopathology , Cells, Cultured , Endopeptidases/biosynthesis , Enzyme Induction , Humans , Synovial Membrane/pathologyABSTRACT
A small hospital reports on the results of 1302 appendectomies: all degrees of morbidity of the appendix and all patient ages are represented. There were only 2 deaths (0.15%), which also illustrates the very satisfactory success rate in the 16 "urgent early relaparotomies" (only 1 of 11 patients died). Richly demonstrated by case reports, it deals with diagnostic, indicative, and intraoperative problems and finally broaches the subject of "suppurative pylethrombophlebitis" secondary to acute appendicitis, including the question about its fateful course.
Subject(s)
Appendectomy , Abscess/etiology , Aged , Appendectomy/adverse effects , Appendicitis/diagnosis , Child , Diagnosis, Differential , Douglas' Pouch , Female , Humans , Intraoperative Complications , Male , Pelvic Inflammatory Disease/diagnosis , Peritoneal Diseases/etiology , Pregnancy , Pregnancy, Ectopic/diagnosis , Thrombophlebitis/diagnosisSubject(s)
Major Histocompatibility Complex , Protein Biosynthesis , Rats, Inbred Strains/genetics , Animals , Antilymphocyte Serum/pharmacology , Cell Membrane/immunology , Chemical Precipitation , Electrophoresis, Polyacrylamide Gel , Genes, MHC Class II , Lymphocyte Culture Test, Mixed , Molecular Weight , Rats , Recombination, GeneticABSTRACT
Recombinational analysis has shown that the rat MHC,RT1 is divided into two regions:RT1.A, which codes for class I (transplantation) antigens, andRT1.B, which controls the humoral immune response and proliferative response to allogeneic cells as well as the expression of class II (Ia) antigens. Serological and sequence studies suggest that there might be more than one antigen-coding locus within theRT1.A region. Results obtained by sequential immunoprecipitation reveal that both regions code for at least two gene products. By implication, theRT1 complex must therefore harbor at least four loci;RT1.A andD coding for class I glycoproteins (45,000 daltons); andRT1.B andE coding for class II (Ia) glycoproteins (35,000 and 28,000 daltons).
