Objective To explore the characteristics of chondrocyte apoptosis following acute osteochondral injury and the effect of intra-articular sodium hyaluronate injection in prevention of chondrocyte apoptosig. Methods Acute osteochondral injuries were created by drilling holes in knees at both sides of 28 rabbits according to Costouros' method. The experimental and control sides were randomized in each animal. Another four rabbits served as a normal control which received dissection of knee joint capsule without osteochondral injury. The experimental knee was injected with 1 % sodium hyaluronate at the end of the operation and then every week postoperatively. TUNEL and fluorescence-activated cell sorter (FACS) were applied to study the injured femoral condyles obtained at different intervals following the drilling injury. Results From day 4 after injury, the injured cartilage specimens displayed a statistically significant increase in overall level of apoptosis. Chondrocyte apoptosis was significantly reduced in the experiment knees compared with the injured ones. Conclusions Chondrocyte apoptosis may contribute to the subsequent development of post-traumatic arthritis. Intra-articular sodium hyaluronate injection just after acute osteochondral injury can suppress chondrocyte apoptosis, and thus help prevent the knee from post-traumatic arthritis.

[Objective]To explore the diagnostic value of conventional ultrasound combined with shear wave elastography (SWE) for sarcopenia in patients with chronic kidney disease (CKD).[Methods]The study included 94 CKD patients (34 with sarcopenia and 60 without). All patient underwent the Simplified Assessment Rating Questionnaire (SARC-CalF),Mini Nutritional Assessment (MNA),Short Physical Performance Battery (SPPB),grip strength test,bioelectrical impedance analysis (BIA),conventional muscle ultrasound and SWE of the thighs. We then compared the differences in indicators between the sarcopenia group and non-sarcopenia group,used Spearman correlation analysis to assess the relationship between the two examinations (conventional ultrasound and SWE) and other clinical indicators,identified the diagnostic markers for sarcopenia,created receiver operating characteristic (ROC) curves,calculated the area under the curve (AUC) and determined the diagnostic performance of conventional ultrasound,SWE and their combination. Binary logistic regression was used to analyze the influencing factors of sarcopenia in CKD patients and a combined diagnosis model was established.[Results]The sarcopenia group showed lower upper arm circumference,calf circumference,6-meter walking speed and handgrip strength than non-sarcopenia group,and the differences were statistically significant (P<0.05). The sarcopenia group exhibited lower SARC-CalF and SPBB scores,as well as more compromised nutritional status. Statistically significant differences were observed in the ultrasound parameters between the two groups,including thickness of the subcutaneous fat and rectus femoris,combined thickness of the rectus femoris and vastus intermedius,rectus femoris cross-sectional area,elastic modulus of the rectus femoris and vastus medialis (all P<0.05). The muscle mass index had a moderate positive correlation with muscle thickness and cross-sectional area of the rectus femoris (0.3