Hsa_circ_0045714 regulates chondrocyte proliferation, apoptosis and extracellular matrix synthesis by promoting the expression of miR-193b target gene IGF1R.

In recent years, some studies have been made on the effects of circular RNA (circRNA) in osteoarthritis (OA) and so on; however, its mechanisms remain to be further explored. Studies have shown that tumor necrosis factor-alpha can inhibit hsa_circ_0045714 expression in chondrocytes so as to upregulate miR-193b expression. Dual-luciferase reporter assay showed that insulin-like growth factor 1 receptor (IGF1R) is a key target gene of miR-193b. Hsa_circ_0045714 over-expression does not influence miR-193b expression, but can inhibit its transcriptional activity, thereby upregulating IGF1R expression. Hsa_circ_0045714 can promote the expression of type II collagen and aggrecan, and upregulate chondrocyte proliferation, while its linear sequences cannot. IGF1R has similar function, while miR-193b can inhibit the expression of type II collagen and aggrecan, and downregulate chondrocyte proliferation but enhance their apoptosis. IGF1R overexpression can reverse the effect of miR-193b, while miR-193b mimics or IGF1R siRNA can inhibit the function of hsa_circ_0045714. Therefore, hsa_circ_0045714 can regulate extracellular matrix synthesis as well as proliferation and apoptosis of chondrocytes by promoting the expression of miR-193b target gene IGF1R. The findings will provide new proofs for studies on the applications of circRNA in OA and other orthopedic diseases.

[Application of 3D digital orthopedic techniques in treatment of acetabular fracture].

OBJECTIVE: To evaluate the therapeutic effect of three-dimensional digital orthopedic techniques in treatment of acetabular fractures. METHODS: We retrospectively analyzed 50 cases of acetabular fracture treated between March, 2007 and December, 2013. The lamellar CT scanning data were imported into Mimics software, and 3D anatomical models of the pelvic and proximal femur were reconstructed. Computer-assisted analysis was carried out to understand the condition of fractures and simulate fracture reduction. The pelvic models were manufactured by rapid prototyping technique for definite diagnosis and typing of acetabular fractures and subsequent surgical treatment. RESULTS: Three-dimensional reconstruction images and rapid prototyping pelvic models faithfully represented the findings in operations. Preoperative simulation of the operation shortened the time of operation and reduced the volume of bleeding in the operation. All the patients were followed up for 6 to 24 months. According to Matta imaging score, anatomical reduction was achieved in 41 cases and satisfactory reduction in 9 cases. According to the Harris functional criteria, 32 patients had excellent, 12 had good and 6 had acceptable outcomes with a rate of excellent and good outcomes of 88%. CONCLUSION: Three-dimensional digital orthopedic techniques allow accurate display of the acetabulum and the spatial relation of the anatomic structures to assist in fracture diagnosis, typing and treatment.