Objective Melatonin (MLT) can increase the expression of cartilage-derived growth factor and stimulate the synthesis of cartilage matrix. To investigate the prevention and treatment effects of MLT on damaged cartilage through observing the expressions of bone morphogenetic protein 2 (BMP-2) and interleukin 1β (IL-1β) in articular cartilage of the rats with osteoarthritis (OA). Methods Forty SPF 4-week-old male SD rats (weighing 120-150 g) were randomly divided into 4 groups (n=10): normal control group (group A), OA group (group B), OA/pinealectomy group (group C), and OA/ pinealectomy/MLT group (group D). The rats of group A served as a control without treatment. The rats of groups B, C, andD underwent left knee joint injection of 0.2 mL 4% papain solution 1 time every other day for 2 weeks for establ ishing OAmodel. Two weeks after papain injection, the rats of groups C and D were exposed to continuous l ight for 24 hours (intensity of illumination: 500 lx) for creating pinealectomy models. And at the next day after pinealectomy model establ ishing, the rats of group D were treated with intra-articular injections of 0.2 mL 20 mg/mL MLT solution 4 times a week for 4 weeks. At 1 week after last MLT injection, the venous blood samples were taken in groups A, B, and C to test the level of serum MLT by ELISA, respectively, and then the specimens of left cartilage of femoral condyle were harvested for macroscopic, histological, and immunohistochemical examinations in 4 groups. Results The OA and pinealectomy models of rats were successfully establ ished, and all rats survived. There were significant differences in the serum MLT level among groups A, B, and C, and among different time points at the same group (P lt; 0.05). In group A, articular cartilage surface was smooth and elastic, and chondrocytes arranged regularly. In groups B and C, articular cartilage surface was rough, cartilage defects and subchondral bone exposure were observed in some areas, and chondrocytes arranged irregularly. In group D, cartilage surface was more smooth than that in groups B and C, and the degrees of cartilage defect and subchondral bone exposure decreased with regular arrangment of chondrocytes. There were significant differences in Mankin scores and integral absorbance values among 4 groups (P lt; 0.05). Conclusion Exposure to continuous l ight can accelerate degeneration process of articular cartilage of OA rats. Injections of 0.2 mL MLT solution (20 mg/mL) by intra-articular for 4 weeks can inhibit the progress of cartilage defects. Upregulationof anabol ic factor of BMP-2 as well as down-regulation of catabol ic factors of IL-1β is associated with cartilage repairin the pathological features of OA.
Objective To summarize operative procedure and the effectiveness of open reduction with internal fixation or radial head replacement for the treatment of Essex-Lopresti injury. Methods Between November 2002 and October 2010, 10 patients with Essex-Lopresti injury were treated. There were 8 males and 2 females with a mean age of 36 years (range, 20-56 years). Eight cases were fresh closed fracture within 2 days. According to Mason classification, 5 fracture were typeII, 3 were type III. The other 2 cases were old fracture within 3 months. Wrist joint X-ray revealed that all the patients had distal radioulnar joint dislocation. Open reduction with internal mini-plate or absorbable screw fixation was performed in 5 cases, and radial head replacement in 5 cases; meanwhile, the distal radioulnar joint was reducted and fixed. Results All incisions healed by first intention without infection or bone nonunion. The patients were followed up 7 to 24 months with an average of 14.7 months. The X-ray films showed fracture heal ing at 9-20 weeks (mean, 16.3 weeks); distal radioulnar joint was stable without shortening or shift of proximal radius. According to elbow cl inical evaluation system, the results were excellent in 5 cases, good in 3 cases, and fair in 2 cases. According to wrist cl inical evaluation, the results were excellent in 7 cases, good in 2 cases, and fair in 1 case. All patients had good elbow stabil ity, and recovered quickly. Conclusion Early diagnosis, operation, and functional exercises are important to obtain an excellent result in treating Essex-Lopresti injury.