Subchondral bone plate thickening precedes chondrocyte apoptosis and cartilage degradation in spontaneous animal models of osteoarthritis.

Osteoarthritis (OA) is the most common joint disorder characterised by bone remodelling and cartilage degradation and associated with chondrocyte apoptosis. These processes were investigated at 10, 16, 24, and 30 weeks in Dunkin Hartley (DH) and Bristol Strain 2 (BS2) guinea pigs that develop OA spontaneously. Both strains had a more pronounced chondrocyte apoptosis, cartilage degradation, and subchondral bone changes in the medial than the lateral side of the tibia, and between strains, the changes were always greater and faster in DH than BS2. In the medial side, a significant increase of chondrocyte apoptosis and cartilage degradation was observed in DH between 24 and 30 weeks of age preceded by a progressive thickening and stiffening of subchondral bone plate (Sbp). The Sbp thickness consistently increased over the 30-week study period but the bone mineral density (BMD) of the Sbp gradually decreased after 16 weeks. The absence of these changes in the medial side of BS2 may indicate that the Sbp of DH was undergoing remodelling. Chondrocyte apoptosis was largely confined to the deep zone of articular cartilage and correlated with thickness of the subchondral bone plate suggesting that cartilage degradation and chondrocyte apoptosis may be a consequence of continuous bone remodelling during the development of OA in these animal models of OA.

Long-term survival in patients with human immunodeficiency virus-associated small non-cleaved cell lymphoma: the role for short course intensive chemotherapy.

While intensive chemotherapy is recommended for the treatment of non-HIV related adult small non-cleaved lymphoma (SNCL), including Burkitt's and Burkitt-like lymphoma, optimal treatment for patients with HIV-associated SNCL is not known. We assessed remissions and survival in a cohort of 44 consecutive HIV positive patients diagnosed with SNCL at our hospital between June 2000 and November 2001 using chart and pathology data. Median follow-up, survival and survival at the median follow-up time were 4.5 months, 4 months and 49% respectively. Of this cohort 39% were complete responders (CR) and 36% were long-term lymphoma-free survivors. Two patients relapsed from CR. Short course intensive chemotherapy (McMaster) was administered to 23 patients; 17 received less intensive conventional combination chemotherapy; and four received single-agent chemotherapy or no treatment. In the McMaster group, 38% (9/23) achieved CR with no relapses. Seven patients (30%) died of toxicity compared with one (6%) in the less intensively treated group. Of the stage I patients, 75% (6/8) achieved long-term CR with half being treated conventionally. Conventional chemotherapy may be curative for early stage HIV-SNCL. In advanced disease, McMaster chemotherapy was found to be associated with substantial early mortality but was curative in a significant number of patients.