Objective To investigate the biocompatibility of type I collagen scaffold with rat bone marrow mesenchymal stem cell (BMSCs) and its role on proliferation and differentiation of BMSCs so as to explore the feasibility of collagen scaffold as neural tissue engineering scaffold. Methods Type I collagen was used fabricate collagen scaffold. BMSCs were isolated by density gradient centrifugation. The 5th passage cells were used to prepare the collagen scaffold-BMSCs complex. The morphology of collagen scaffold and BMSCs was observed by scanning electron microscope (SEM) and HE staining. The cell proliferation was measured by MTT assay at 1, 3, 5, and 7 days after culturein vitro. After cultured on collagen scaffold for 24 hours, the growth and adhesion of green fluorescent protein positive (GFP+) BMSCs were observed by confocal microscopy and live cell imaging. Results The confocal microscopy and live cell imaging results showed that GFP+ BMSCs uniformly distributed in the collagen scaffold; cells were fusiform shaped, and cell process or junctions between the cells formed in some cells, indicating good cell growth in the collagen scaffold. Collagen scoffold had porous fiber structure under SEM; BMSCs could adhered to the scaffold, with good cell morphology. The absorbance (A) value of BMSCs on collagen scaffold at 5 and 7 days after culture was significantly higher than that of purely-cultured BMSCs (t=4.472,P=0.011;t=4.819,P=0.009). HE staining showed that collagen scaffold presented a homogeneous, light-pink filament like structure under light microscope. BMSCs on the collagen scaffold distributed uniformly at 24 hours; cell displayed various forms, and some cells extended multiple processes at 7 days, showing neuron-like cell morphology. Conclusion Gelatinous collagen scaffold is easy to prepare and has superior biocompatibility. It is a promising scaffold for neural tissue engineering.
ObjectiveTo explore the effectiveness and safety of closed reduction combined with Taylor three-dimensional space stent fixation in treatment of supracondylar femoral fractures in children.MethodsBetween July 2008 and July 2016, 20 patients with supracondylar femoral fractures were treated with closed reduction combined with Taylor three-dimensional space stent fixation. There were 14 males and 6 females, with an average age of 10.3 years (range, 6-14 years). The cause of injury was traffic accident in 5 cases, falling from high place in 6 cases, and falling in 9 cases. All fractures were closed fractures. Among them, 12 cases were flexion type and 8 cases were straight type. According to AO classification, 12 cases were rated as type A1 and 8 cases as type A2. The fractures were over 0.5-5.0 cm (mean, 2.5 cm) of the epiphysis line. The time from injury to surgery was 2-8 days (mean, 3.5 days). Postoperative knee joint function was evaluated based on the Kolment evaluation criteria.ResultsAll children were followed up 6-24 months (mean, 18.1 months). There was no complication such as nail infection, vascular nerve injury, external fixation looseing, fracture displacement, or re-fracture. All fractures healed and the fracture healing time was 4-6 weeks with an average of 4.5 weeks. The stent removal time was 8-12 weeks (mean, 9.5 weeks). The gait and knee function recovered, and there was no abnormality of the epiphysis. At last follow-up, the knee joint function were excellent in 18 cases and good in 2 cases according to the Kolment evaluation criteria, and the excellent and good rate was 100%.ConclusionClosed reduction combined with Taylor three-dimensional space stent fixation is an effective treatment for the children with supracondylar femoral fractures, with small trauma and rapid recovery. It can avoid damaging the tarsal plate, be high fracture healing rate, and promote the recovery of limb function.