Effect of N-cadherin on Chondrogenic Differentiation of Bone Marrow-Derived Mesenchymal Stem Cells through Wnt Signaling Pathway.

This study aimed to compare and analyze the effect of N-cadherin on chondrogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) and to explore the related mechanism, so as to provide a novel theoretical basis for the clinical work of articular cartilage injury regeneration and repair. For this purpose, the experimental animals were clean grade SD rats (aged 5-6 weeks, weighing 180-250g). Alcian blue staining was carried out to observe the induced chondrogenesis following N-cadherin inhibition. The specific role of N-cadherin in the Wnt signaling pathway and chondrogenic differentiation of BMSCs was detected by Western blot; while the effect of N-cadherin on the molecular level changes of ß-catenin in the cytoplasm was evaluated by fluorescence quantitative real-time PCR (qRT-PCR). In addition, immunoprecipitation (IP) was used for the verification of the interaction between N-cadherin and ß-catenin. Results showed that under the light microscope, 90% of the BMSCs at the third generation, 90% of the cells were fused. Alcian blue staining showed that the green staining area in the BMP2 induction group was large and dense, while that in the N-cadherin inhibition group and blank control group was small and sparse. Western blot revealed that N-cadherin and SOX9 were significantly developed in the BMP2 induction group, but Wnt3a was not significantly developed. While in the N-cadherin inhibition group, the development of Wnt3a was obvious, yet without evident development of N-cadherin and SOX9. The qRT-PCR indicated that the relative mRNA expression of Wnt3a was significantly increased in the N-cadherin inhibition group (P<0.05). However, no obvious difference was observed in the mRNA expression of ß-catenin between the BMP2 induction group and the N-cadherin inhibition group (P>0.05). Western blot indicated that in the BMP2 induction group; there existed the development of ß-catenin, significant development of phos-GSK-3ß and total GSK-3ß, but no obvious development of Wnt3a. In the N-cadherin inhibition group, there was significantly enhanced development of Wnt3a and ß-catenin than that before, blurred development of phos-GSK-3ß than that before, and also obvious development of total GSK-3ß with little change from before. N-cadherin promoted the expression of ß-catenin mostly in the cell membrane, but only a few in the cytoplasm and nucleus. Additionally, verification by IP showed that N-cadherin and ß-catenin were developed on N-cadherin and ß-catenin bands, suggesting an interaction between N-cadherin and ß-catenin. According to these results, N-cadherin can ultimately promote chondrogenic differentiation of BMSCs by inhibiting the Wnt signaling pathway.

Arthroscopic patelloplasty and circumpatellar denervation for the treatment of patellofemoral osteoarthritis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Patellofemoral osteoarthritis commonly occurs in older people, often resulting in anterior knee pain and severely reduced quality of life. The aim was to examine the effectiveness of arthroscopic patelloplasty and circumpatellar denervation for the treatment of patellofemoral osteoarthritis (PFOA).</p><p><b>METHODS</b>A total of 156 PFOA patients (62 males, 94 females; ages 45-81 years, mean 66 years) treated in our department between September 2012 and March 2013 were involved in this study. Clinical manifestations included recurrent swelling and pain in the knee joint and aggravated pain upon ascending/descending stairs, squatting down, or standing up. PFOA was treated with arthroscopic patelloplasty and circumpatellar denervation. The therapeutic effects before and after surgery were statistically evaluated using Lysholm and Kujala scores. The therapeutic effects were graded by classification of the degree of cartilage defect.</p><p><b>RESULTS</b>A total of 149 cases were successfully followed up for 14.8 months, on average. The incisions healed well, and no complications occurred. After surgery, the average Lysholm score improved from 73.29 to 80.93, and the average Kujala score improved from 68.34 to 76.48. This procedure was highly effective for patients with cartilage defects I-III but not for patients with cartilage defect IV.</p><p><b>CONCLUSIONS</b>For PFOA patients, this procedure is effective for significantly relieving anterior knee pain, improving knee joint function and quality of life, and deferring arthritic progression.</p>

The value of 3 dimensional-fat suppression-spoiled gradient-recalled acquisition sequence on single compartment osteoarthritis for unicompartmental arthroplasty preoperative assessment / 中华外科杂志

<p><b>OBJECTIVE</b>To analyze the 3 dimensional-fat suppression-spoiled gradient-recalled acquisition (3D-FS-SPGR) sequence in the diagnosis of knee articular cartilage injury.</p><p><b>METHODS</b>A total of 56 knee osteoarthritis patients (26 males, 30 females, ages 52-73 years, mean 61.8 years) treated in Department of Orthopedics, Chinese People's Liberation Army General Hospital between June 2013 and May 2014 were involved in this study. All patients underwent knee MRI, plus 3D-FS-SPGR sequence, arthroscopic exploration, and in contrast to the results of MRI results analysis, evaluation 3D-FS-SPGR and conventional sequence of cartilage damage consistent with the arthroscopic accuracy.</p><p><b>RESULTS</b>Divided 56 knee joints into 336 cartilage articular surface, included 55.1% normal articular surface, 21.4% early osteoarthritis and 23.5% advanced osteoarthritis. The accordance of 3D-FS-SPGR sequence grading and arthroscopic was 90.2%. The sensitivity of 3D-FS-SPGR sequence was 93.1%, specificity was 98.3%, and Kappa value was 0.849. The sensitivity of T2WI sequence was 84.4%, specificity was 96.9%, and the Kappa value was 0.671.</p><p><b>CONCLUSION</b>For unicompartment osteoarthritis , MRI 3D-FS-SPGR sequence is effective in sensitivity and specificity of cartilage damage.</p>