RÉSUMÉ
Objective To explore the influence of elevating the oxygen pressure on articular chondrocytes in vitro.Method A hydrogen peroxide induced human articular chondrocyte damage model was established.Then the articular chondrocyte viability was detected using the CCK-8 kit.Collagen Ⅱ(COL Ⅱ),The expression levels of aggrecan (ACAN),matrix metalloproteinase 13 (MMP13) and adisintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5) were detected using the realtime PCR and Western blotting.Result The viability of articular chondrocytes improved at 12 h but decreased at 24 h after the stimulation of hydrogen peroxide.Twenty-four hours later,the average expression level of COL Ⅱ and ACAN decreased(P＜0.05),while that of MMP13 and ADAMTS5 elevated(P＞0.05).Conclusion Hydrogen peroxide induced elevation of the extracellular oxygen pressure can influence the synthesis and degradation of the articular chondrocyte extracellular matrix.
RÉSUMÉ
Objective To investigate the osteogenesis capability of different frequency extracorporeal shock wave.Methods 39 rabbits received different frequency extracorporeal shock wave at the middle potion of tibia for 3 or 7 days,these rabbits were then sac rificed and the tibia bones were collected to process for HE and toluidine blue staining,the pathological changes were observed under the light microscope.Results After different frequency extracorporeal shock wave treatment,the typical periosteal reaction were observed,external periosteum bleeded and thickened but there was no reaction at internal periosteum,marrow cavity opened and fibrosed.the osteoblast-1iking cell proliferated,however,no cartilage cells were observed;The rabbits received 7 days shock wave treatment showed more severe reaction than those for 3 days.The shock wave at lower frequency showed more severe reaction than higher frequency.Conclusion shock wave induced osteogenesis through the periosteal reaction of external periosteum;the osteogenesis capability of different frequency extracorporeal shock wave were affected by the frequency.Higher frequency of shock wave was not the ideal way to promote osteogenesis.