ABSTRACT
BACKGROUND:Both calcium phosphate cement II and recombinant human bone morphogenetic protein have certain osteoinductive effects, which have the possibility of repairing tendon-bone interface injury. OBJECTIVE: To investigate the osteoinductive effect of calcium phosphate cement II and its biomechanics analysis of repairing tendon-bone interface injury. METHODS:Five out of 35 adult healthy New Zealand white rabbits were randomly selected and their bilateral shoulder joint tendon-bone interface specimens were taken as normal control group after being sacrificed. The remaining 30 rabbits were used to make animal models of tendon-bone interface injury and then randomly divided into experimental and model groups. Rabbits in the model group had no treatment, and those in the experimental group were treated with calcium phosphate cement II. RESULTS AND CONCLUSION: After repair with calcium phosphate cement II, the injured tendon-bone interface of rabbits was obviously restored, and the repair effect became better with time. The expression level of bone morphogenetic protein 2 was also increased accordingly. The maximum tensile strength and the maximum stiffness of the injured tendon-bone interface were obviously increased. These results demonstrate that calcium phosphate cement II combined with recombinant human bone morphogenetic protein has good osteoinductive and repair effect in repair of tendon-bone interface injury.
ABSTRACT
Objective To investigate effects of Tanshinone Ⅱ A (Tan Ⅱ) on proliferation and apoptosis of myeloblastic leukemia cell lines.Methods NB4,K562 and THP-1 cells were incubated with TanⅡA for 24,48 and 72 hours.Ddaunorubicin was used as a positive control.Cell proliferation was monitored by MTT assay.Cell apoptosis and cell cycle were determined by Annexin Ⅴ-FITC/PI flow cytometry.Expression of Caspase-3 was quantified by spectrophotometry.Results After incubation with various leukemia cells for 24,48 and 72 hours,Tan Ⅱ inhibited proliferation of NB4 cells with IC50 of 24.11,9.60 and 7.28 μmol/L,inhibited K562 cells with IC50 of 31.75,11.88 and 6.81 μmol/L and inhibited THP-1 cells with IC50 of 111.10,32.82 and 11.82,respectively.After treatment with Tan Ⅱ for 48 hours,cell apoptosis,the number of G1 phase cells and the expression of Caspase-3 in all three leukemia cell lines were increased significantly comparing with the blank control group (P ＜ 0.05).Conclusions Tan Ⅱ A has proliferation inhibitory effect on myeloblastic leukemia cell lines by the order of effect NB4＞K562＞THP-1.Tan ⅡA displays anti-leukemia activity possibly through arresting leukemia cells in G1 phase and inducing apoptosis by increasing Caspase-3 expression.