ObjectiveTo explore the potential role of WNT6 in the proliferation, differentiation, and migration of bone marrow mesenchymal stem cells (BMSCs). MethodsMouse BMSCs were cultured to the cell fusion of 30%-50%, and divided into different groups. WNT6 knockdown included 3 experiment groups:cells transfected with WNT6 specific short hairpin RNA (shRNA) (group A1), cells transfected with control shRNA group (group B1), and nontransfected cells (group C1). WNT6 over-expression included 3 groups:cells transfected with WNT6 recombinant plasmid (group A2), cells transfected with blank vector (group B2), and non-transfected cells (group C2). After transfection, the stably transfected cells were cultured for 48 hours. Cell morphology was observed under inverted microscope; real-time fluorescent quantitative PCR was used to analyze WNT6 mRNA levels; Western blot was used to detect WNT6 and Ki67 protein expressions; cell proliferation was assayed by MTT method, and cell migration was detected by Transwell assay. After cells were cultured in osteogenic differentiation medium for 12 days, the alkaline phosphatase (ALP) activity and calcium deposits were detected by biochemical determination. ResultsThe inverted microscope observation showed that the cell morphology were similar among groups A1, B1, C1, and A2, B2, C2. The WNT6 mRNA and protein levels, Ki67 protein level, cell proliferation, cell migration, ALP activity, and calcium deposition in group A1 were all significantly lower than those in groups B1 and C1 (P<0.05), but there was no significant difference between groups B1 and C1 (P>0.05). On the contrary, the above indexes in group A2 were all significantly higher than those in groups B2 and C2 (P<0.05), but no significant difference was shown between groups B2 and C2 (P>0.05). ConclusionWNT6 can promote the proliferation and migration, as well as can enhance osteogenic differentiation ability in mouse BMSCs.
Objective To investigate the relationship between the initial stabil ity and infected loosening of the total hip arthroplasty (THA) prosthesis. Methods From January 2000 to December 2008, 110 cases (110 hips) were treated with THA revision. Among them, 15 cases (15 hips) were confirmed infected loosening. There were 8 males and 7 females with anaverage age of 62 years (range 42-75 years). The infected signs were found from 6 months to 2 years after initial THA. All of them had Tsukayama type IV and late infection, including 6 cases of acetabular infected loosening (5 cases of one-stage and 1 case of two-stage acetabular revision), 7 cases of simple infected loosening of femoral prosthesis (4 cases of one-stage and 3 cases of twostage femoral prosthesis revision), and 2 cases of joint capsule infection and sinus without prosthesis loosening (debridement and continuous irrigation). Results All incisions healed by first intention. Fifteen patients were followed up for 12 to 36 months (average 24 months). In 13 cases of revision, postoperative X-ray films showed that femoral acetabular prostheses were in good position, and had no cl inical and imaging infective signs of loosening. In 2 cases of joint capsule infection, sinus recurred 6 months postoperation without hip joint pain, the function of weight-bearing and walking of hip joint was normal. Harris score increased from preoperative average of 42 to postoperative average of 85; the results were excellent in 4 cases, good in 7 cases, and fair in 4 cases. Conclusion The infection of THA may occur in the whole joint, half-joint or just in joint capsule. The initial stabil ity of the prosthesis would affect the long-term survival of the prothesis. If the prosthesis initial stabil ity is obtained, even if there are infective factors, infections would also be l imited.
ObjectiveTo explore the effectiveness of modified Ilizarov semi-ring external fixator combined with an ulnar osteotomy lengthening in the treatment of old dislocation of the radial head in children. MethodsA retrospective analysis was made on the data of 14 patients with old dislocation of the radial head treated by the modified Ilizarov semi-ring external fixator combined with ulnar osteotomy lengthening between March 2012 and January 2015. The age ranged from 2 to 13 years (mean, 7.2 years), including 12 boys and 2 girls. There was 1 case of congential dislocation of the radial head and 13 cases of old Monteggia fracture. According to the Bado's classification, dislocation was rated as grade Ⅰ in 12 cases and grade Ⅲ in 2 cases. The elbow flexion-extension and forearm pronation and supination were compared between at pre- and post-operation; Mackay evaluation standard of elbow joint function was used to evaluate the effectiveness. ResultsThe operation time ranged from 50 to 65 minutes (mean, 58 minutes). All patients were followed up 6-33 months (mean, 21 months). No complication of infection, myositis ossificans, or redislocation occurred. X-ray film showed bony healing at ulnar osteotomy site within 82-114 days (mean, 90 days). The elbow flexion-extension and forearm pronation and supination were significantly improved at postoperation when compared with preoperation (P<0.05). The results of Mackay function assessment were excellent in 12 cases and good in 2 cases. ConclusionThe modified Ilizarov semi-ring external fixator combined with an ulnar osteotomy lengthening has the advantages of small incision, easy removal of fixator, satisfactory reduction, and no nonunion at ulnar osteotomy site in the treatment of old dislocation of the radial head, but the long-term effectiveness still needs to be followed up.