Objective Metal wear products cause the aseptic loosening of joint prosthesis. To investigate the effect of metal ions Co2+ and Cr3+ on the osteoblast apoptosis, cell cycle distribution, and secretion of alkal ine phosphatase (ALP), and to search a method to prevent and treat aseptic loosening. Methods The mouse calvarial osteoblasts (MC3T3-E1) were cultured in vitro to 3-5 generations (5 × 105 cells/ mL) and divided into 2 groups: the experimental group and the controlgroup. The osteoblasts were cultured in α-MEM medium containing 10%FBS (the control group), and the mixed solution ofCoCl2 and CrCl3 was added after the osteoblasts cultured in α-MEM medium containing 10%FBS attached completely (the experimental group). At 12, 24, and 48 hours after culture, the osteoblast apoptosis and the cell cycle distribution were assessed by flow cytometry; and ELISA method was appl ied to detect ALP content in serum supernatant. Results At 12, 24, and 48 hours after culture, the apoptosis rates in the experimental group (13.90% ± 0.52%, 14.80% ± 0.41%, and 13.40% ± 0.26%) were significantly higher than those in the control group (8.56% ± 0.31%, 8.19% ± 0.24%, and 2.15% ± 0.11%), (P lt; 0.05); G2M (dividing phase) distribution ratio significantly decreased and G0G1 (dormancy stage) distribution ratio significantly increased when compared with those in the control group (P lt; 0.05); and the absorbency (A) values of ALP were 0.955 ± 0.052, 0.624 ± 0.041, and 0.498 ± 0.026 in the exprimental group, and were 1.664 ± 0.041, 1.986 ± 0.024, and 2.192 ± 0.041 in the control group, showing significant differences between 2 groups (P lt; 0.05). Conclusion Metal ions Co2+ and Cr3+ have a marked effect on osteoblasts cell cycle distribution, which can make most of the cells to be in dormancy stage (G0G1), up-regulate the apoptosis rate and inhibit the releasion of ALP from osteoblasts.
Objective To observe the human mononuclear cell releasing TNF-α and the activation of Caspase-3 during apoptosis after stimulated by Co2+ and Cr3+, to discuss the mechanism of artificial joint wear production metal ion on aseptic loosening. Methods CoCl2 powder and CrCl3 powder were dissolved by asepsis inject water, preparing solution for10 mg/L and 500 mg/L, respectively. Mononuclear cells were acquired from peripheral blood, 4 × 106/culture dish. According to the difference of culture solution, the cells were divided into 3 groups. Group A: mononuclear cell was culture with normal sal ine as control; group B: mononuclear cell was cultured with CoCl2 solution; group C: mononuclear cell was cultured with CrCl3 solution. The production of TNF-α was assessed by ELISA, the activation of Caspase-3 was measured by colorimetric assay and the apoptotic cell was detected by TUNEL assays at 12, 24 and 48 hours after co-cultured respectively. Results The concentration of TNF-α and the expression of Caspase-3 in groups B and C were higher than those in group A (P lt; 0.05), and reached the peak level at 24, 48 hours, respetively. The TUNEL positive cells were detected in the all groups, nucleus was pyknotic and darker-staining, cell body was crinkle and cell membrane was integrity. There were significant differences in the apoptosis rate between groups B, C and group A (P lt; 0.05). And the activation of Caspase-3 increased and had the positive correlation with the apoptosis rate (r=0.765). Conclusion Co2+ and Cr3+ ions can stimulate human mononuclear cell to release TNF-α and induce human mononuclear cell apoptosis, which result in periprosethetic osteolysis and related to activation of Caspase-3.
【Abstract】 Objective To review the recent progress of hi p resurfacing arthroplasty. Methods Literatureconcerning hip resurfacing arthroplasty and current achievements was extensively and comprehensively reviewed. Results The new metal-on-metal hip resurfacing arthroplasty made much progress especially in materials and technology, and the results were satisfactory for short-term follow-up. This was increasingly widely used especially in treating young patients. But there were still some problems such as elevation of metal ions which had already aroused publ ic attention. Conclusion The new metal-onmetal hip resurfacing arthroplasty is an efficient method in the treatment of adult hip joint disease and has an encouraging future, but long-term follow-up is still needed.
In recent years, bone implant materials such as titanium and titanium alloys have been widely used in the biomedical field due to their excellent mechanical properties and good biocompatibility. However, in clinical practice, bacterial adhesion to the material surface and postoperative infection issues may lead to implantation failure. Based on the antibacterial mechanism, this review elaborated on the antibacterial surface design of titanium implants from the aspects of anti-bacterial adhesion, contact sterilization and photocontrol sterilization. Surface modification of titanium or titanium-based alloy implants with different techniques can inhibit bacteria and promote osseointegration. Thus, the application range of multifunctional titanium-based implants in the field of orthopedics will be expanded.