The effect of overexpressing the Indian hedgehog (IHH) gene on the chondrogenic differentiation of rabbit bone marrow-derived mesenchymal stem cells (BMSCs) was investigated in a simulated microgravity environment. An adenovirus plasmid encoding the rabbit IHH gene was constructed in vitro and transfected into rabbit BMSCs. Two large groups were used: conventional cell culture and induction model group and simulated microgravity environment group. Each large group was further divided into blank control group, GFP transfection group, and IHH transfection group. During differentiation induction, the expression levels of cartilage-related and cartilage hypertrophy-related genes and proteins in each group were determined. In the conventional model, the IHH transfection group expressed high levels of cartilage-related factors (Coll2 and ANCN) at the early stage of differentiation induction and expressed high levels of cartilage hypertrophy-related factors (Coll10, annexin 5, and ALP) at the late stage. Under the simulated microgravity environment, the IHH transfection group expressed high levels of cartilage-related factors and low levels of cartilage hypertrophy-related factors at all stages of differentiation induction. Under the simulated microgravity environment, transfection of the IHH gene into BMSCs effectively promoted the generation of cartilage and inhibited cartilage aging and osteogenesis. Therefore, this technique is suitable for cartilage tissue engineering.

ObjectivesTo investigate the effectiveness of intermittent pneumatic compression (IPC) devices combined with anticoagulants for the prevention of deep vein thrombosis (DVT) after total knee arthroplasty (TKA).Patients and methodsIn total 120 patients were involved in this pilot study. Patients in the control group received 10 mg of rivaroxaban per day after surgery. In addition to the prescription of rivaroxaban, IPC devices were used in the experimental group. The diagnosis of DVT was made by compression duplex ultrasound on postoperative day 9.ResultsThe incidence rates of overall, proximal, distal, and intermuscular DVT were 8.3%, 0%, 1.67%, and 6.67% in the experimental group; and 18.3%, 0%, 5%, and 13.33% in the control group, respectively. The incidence rates of total, distal, and intermuscular DVT in TKA patients was significantly lower in the experimental group than in the control group. For patients with DVT, enoxaparin was used instead of rivaroxaban, and DVT was found to have disappeared 10–14 days postoperatively.ConclusionCompared with the use of rivaroxaban alone, IPC devices combined with anticoagulants can significantly reduce the incidence rate of distal DVT and intermuscular DVT in the early postoperative period after TKA.

To evaluate the effect of leptin combined with CoCl2 on rat femur fracture healing. 48 male Sprague Dawley rats were randomly divided into two main groups. Then standardized femur fractures were created to all rats. Control group rats were treated with 0.5 mL physiological saline, and experimental group rats were treated with 5 μg/Kg.d leptin and 15 mg/Kg.d CoCl2 along with 0.5 mL physiological saline for 42 days intraperitoneally. Each main group was divided into three subgroups for each evaluation at second, fourth and sixth weeks, each subgroup included eight rats. The radiological evaluation showed that the fracture healing progress of experimental group was superior to control group from second week. At fourth week, experimental group had better fracture healing progress than control group significantly. Results of biomechanics show the ultimate load (N) and deflection ultimate load (mm) of experimental group was significantly increased than that in control group from fourth week. The present result demonstrated that leptin combined with CoCl2 significantly increased the mRNA expression levels of HIF1A, Vegfa, Runx2, Bmp2, Bglap and Alpl. It suggested that leptin combined with CoCl2 have a positive effect on rat femur fracture healing by activating the HIF1A pathway.