Objective:To investigate the influence of 17β-estradiol(17β-E2)in the proliferation and differentiation capabilities of primary cultured hippocampal neural stem cells(NSCs),and to clarify its potential mechanism.Methods:The NSCs were isolated from the hippocampal tissue of SD rats within 24 h of birth,and divided into control group and 17β-E2 group.Immunofluorescence method was used to detect the expressions of Nestin and 5-ethynyl-2'-deoxyuridine(EdU)in NSCs in two groups,and the proliferation rates of NSCs were calculated.Western blotting method was used to detect the expression level of Nestin protein.Flow cytometry was used to analyze the percentages of NSCs at different cell cycles.Immunofluorescence method was used to identify the expressions of markers for neurons β Ⅲ-tubulin and astrocyte marker glial fibrillary acidic protein(GFAP)in the NSCs after differentiation,and the relative ratio of neurons to astrocytes was calculated.Western blotting method was used to detect the expression levels of β Ⅲ-tubulin and GFAP proteins as well as phosphatidylinositol 3-kinase(PI3K),protein kinase B(Akt),phosphorylated Akt(p-Akt),glycogen synthase kinase-3 beta(GSK-3β),phosphorylated GSK-3β(p-GSK-3β),and beta-catenin(β-catenin)proteins related to PI3K/Akt/GSK-3β pathway.Results:Immunofluorescence assay revealed positive Nestin expression in NSCs in two groups;compared with control group,the proliferation rate of NSCs in 17β-E2 group was increased(P＜0.01).Compared with control group,the expression level of Nestin protein in the NSCs in 17β-E2 group was increased(P＜0.05),and the percentage of NSCs in S phase was increased(P＜0.01).Compared with control group,the relative ratio of neurons to astrocytes in 17β-E2 group was significantly increased(P＜0.05).After differentiation,compared with control group,the expression level of β Ⅲ-tubulin protein in the NSCs in 17β-E2 group was increased(P＜0.05),and the expression level of GFAP protein was decreased(P＜0.01),while the expression levels of Akt,p-Akt,β-catenin,and p-GSK-3β proteins were increased(P＜0.05 or P＜0.01),and the expression level of GSK-3β protein was decreased(P＜0.05).Conclusion:17β-E2 can promote the proliferation of NSCs and facilitate their differentiation towards neurons,and its mechanism may be related to the PI3K/Akt/GSK-3β signaling pathway.

Objective To evaluate the influence of routine lateral release to the clinical outcomes after total knee arthroplasty without patellar resurfacing.Methods The study involved all patients divided into two groups using a randomised group method.During total knee arthroplasty(TKA),forty-three patients were treated with lateral release in the treatment group,while Forty-two patients in the control group were not treated with lateral release.Both groups were assessed for anterior knee pain,patient satisfaction,Knee Surgery Society(KSS)score,KSS function score,patella score,and incidence of postoperative complications.Results After 24 months of follow-up,the treatment group was found to have a lower incidence of anterior knee pain compared to the control group(P<0.05),and there were no statistically significant differences in postoperative satisfaction,complication rate,KSS knee score,KSS function score,and patella score between the two groups(P>0.05).Conclusion The study suggests that routine lateral release can reduce anterior knee pain and does not increase the risk of postoperative complications after total knee arthroplasty without patellar resurfacing.

Objective To evaluate the mid-and long-term clinic results of ceramic-on-ceramic joint in total hip arthroplasty (THA) in younger patients.Methods A retrospective review was made on 72 younger patients who had THA with ceramic-on-ceramic bearings due to femoral head necrosis or inborn hip dysplasia between March 2001 and March 2011.There were 32 females and 40 males,at a mean age of (35.2 ± 7.6)years (range,17-45 years).Patients were evaluated with Harris hip score and University of California,Los Angeles (UCLA) activity score.Radiological findings were recorded including component loosening,ostelysis,and ceramic bearing related complications.Results Duration of followup was (8.5 ±2.4) years (range,5-12 months).At the final follow-up,Harris hip score was increased to (93.8 ±4.3)points (range,85-100 points) compared to preoperative (46.1 ± 12.3) points (range,27-70 points) and UCLA activity score was increased to (7.1 ± 1.4)points (range,4-10 points) compared to preoperative (4.0 ± 1.2) points (range,2-6 points) (P ＜ 0.05).At the final follow-up,no osteolysis or prosthesis loosening occurred,but there were ceramic sandwich liner fractures in two patients (two hips),dislocation in one patient (one hip) and squeaking in one patient (one hip).After revision due to the ceramics break,the 8-year survival rate was 97％ (95％ CI91.9-100.0).Conclusion Ceramicon-ceramic joint in THA satisfies the activity demand in younger patients,with excellent mid-and longterm clinical results.

BACKGROUND:Ribbed anatomic femoral stem meets the biomechanical features of the femur, and has achieved satisfactory clinical efficacy with good initial stability, rapid bone growth and low stress shielding.
OBJECTIVE:To evaluate the design features and clinical results of the cementless anatomic Ribbed femoral stem (Ribbed stem) in total hip arthroplasty.
METHODWe retrospectively analyzed 52 patients (52 hips) with hip joint disease who were treated with Ribbed stem in total hip arthroplasty between March 2010 and March 2012. There were 20 males and 32 females. The mean age was 59 years (range 22-78 years). The mean fol ow-up was 3.1 years (range 2-4 years). The preoperative and postoperative Harris hip scores, the rate of postoperative thigh pain, the incidence of intraoperative femoral fracture, wound healing, dislocation and revision were recorded. Radiographic evaluation was used to evaluate the rate of stem fil , subsidence of femoral stem, periprosthetic radiolucent line, bone ingrowth, stress shielding, and osteolysis.
RESULTS AND CONCLUSION:The incidence of intraoperative femoral fracture was 6%. Al incisions were healed. There were no cases of hip dislocation and revision;the rate of thigh pain was 6%, no patient had thigh pain after 1 year postoperatively. The mean preoperative Harris hip score was 48 points, which improved to a mean of 96 points at the final fol ow-up. Postoperative X-ray showed that al patients had a satisfactory femoral fil in both planes and al of the femoral stems were wel-fixed at the final fol ow-up. The average fil ing rate was 91%, 88%and 86%by normotopia imaging, while 88%, 85%and 81%by lateral imaging, at the metaphysic, middle and distal ends respectively. At the final fol ow-up, 49 hips (92%) showed stable bone ingrowth, 3 hips showed stable fiber ingrowth. No osteolysis around the components at the femur or acetabulum was observed. 5 (10%) hips appeared the subsidence of femoral stems, which were<2 mm. The stress shielding phenomenon occurred in al patients, including first-degree in 31 hips, second-degree in 19 hips, third-degree in 2 hips, and fourth-degree in no case. Experimental findings indicate that, Ribbed stem with a rational design can achieve satisfactory clinical outcomes with good initial stability, rapid bone growth and low stress shielding.