These recommendations are based on the consensus of clinical experts from a wide range of disciplines taking available evidence into account while balancing the benefits and risks of nonpharmacological, pharmacological, and surgical treatment modalities, and incorporating their preferences and values. Different backgrounds in terms of patient education or drug availability in different countries were not evaluated but will be important.
Objective. To determine the relative expressions of matrix metalloprotease (MMP) genes pro-MMP1 and pro-MMP3 in the cartilage of rabbits with experimentally induced osteoarthritis (OA), and to assess the role of the chondrocyte in this process.Methods. OA was induced in rabbits after partial medial meniscectomy. Rabbits were killed at 4 weeks or 8 weeks, and total cellular RNA was prepared from cartilage and probed by Northern blotting with pro-MMP 32P-labeled complementary DNA. Monolayer chondrocytes were used to assess MMP-inducing activity of chondrocyte factor@).Results. Pro-MMP messenger RNAs (mRNAs) were up-regulated in experimental OA cartilage; pro-MMP3 mRNA expression exceeded that of pro-MMP1. Conditioned medium from OA-derived chondrocytes upregulated pro-MMP mRNAs in normal chondrocytes.Conclusion. Up-regulation of MMP genes in this OA model may contribute to cartilage degradation. Chondrocytes up-regulate MMP genes via an autocrine pathway .Osteoarthritis (OA), characterized by progressive destruction of articular cartilage, is purported to
We studied ten femoral heads from eight patients suffering from rapidly destructive arthropathy (RDA) of the hip. At surgery, 1-3.5 ml of synovial fluid, ranging from citrous to hemorrhagic, was aspirated from six joints. This fluid was viscous, pauci-cellular and did not contain calcium pyrophosphate dihydrate (CaPPD) crystals, although significant amounts of alizarin S-positive material was found in three joints. Significant synovial hyperplasia was found in four joints and moderate hyperplasia in two. Synovium was hypertrophic, hypercellular and slightly to moderately fibrotic. It lacked evidence of perivascular inflammatory infiltrates. Synovium often contained amyloid micro-deposits and alizarin S-positive osteocartilagenous debris surrounded by macrophages. Synovial hyperplasia had a good correlation with osteocartilagenous debris and a poor correlation with amyloid infiltration. Femoral heads were usually flattened and exhibited large areas of exposed bone spotted by plugs of fibro-cartilagenous tissue. Subchondral bone contained large ischemic and necrotic areas, bone marrow atrophy and fibrosis, and intense bone remodeling. Subchondral bone necrosis and ischemia were the most significant findings of this study and their role in the development of RDA is discussed.
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