Objective To study the outcomes of nerve defect repair with the tissue engineered nerve, which is composed of the complex of SCs, 30% ECM gel, bFGF-PLGA sustained release microspheres, PLGA microfilaments and permeable poly (D, L-lacitic acid) (PDLLA) catheters. Methods SCs were cultured and purified from the sciatic nerves of 1-day-old neonatal SD rats. The 1st passage cells were compounded with bFGF-PLGA sustained release microspheres andECM gel, and then were injected into permeable PDLLA catheters with PLGA microfilaments inside. In this way, the tissueengineered nerve was constructed. Sixty SD rats were included. The model of 15-mm sciatic nerve defects was made, and then the rats were randomly divided into 5 groups, with 12 rats in each. In group A, autograft was adopted. In group B, the blank PDLLA catheters with PBS inside were used. In group C, PDLLA catheters, with PLGA microfilaments and 30% ECM gel inside, were used. In group D, PDLLA catheters, with PLGA microfilaments, SCs and 30% ECM gel inside, were used. In group E, the tissue engineered nerve was appl ied. After the operation, observation was made for general conditions of the rats. The sciatic function index (SFI) analysis was performed at 12, 16, 20 and 24 weeks after the operation, respectively. Eelectrophysiological detection and histological observation were performed at 12 and 24 weeks after the operation, respectively. Results All rats survived to the end of the experiment. At 12 and 16 weeks after the operation, group E was significantly different from group B in SFI (P lt; 0.05). At 20 and 24 weeks after the operation, group E was significantly different from groups B and C in SFI (P lt; 0.05). At 12 weeks after the operation, electrophysiological detection showed nerve conduct velocity (NCV) of group E was bigger than that of groups B and C (P lt; 0.05), and compound ampl itude (AMP) as well as action potential area (AREA） of group E were bigger than those of groups B, C and D (P lt; 0.05). At 24 weeks after the operation, NCV, AMP and AREA of group E were bigger than those of groups B and C (Plt; 0.05). At 12 weeks after the operation, histological observation showed the area of regenerated nerves and the number of myel inated fibers in group E were significantly differents from those in groups A, B and C (Plt; 0.05). The density and diameter of myel inated fibers in group E were smaller than those in group A (Plt; 0.05), but bigger than those in groups B, C and D (P lt; 0.05). At 24 weeks after the operation, the area of regenerative nerves in group E is bigger than those in group B (P lt; 0.05); the number of myel inated fibers in group E was significantly different from those in groups A, B, C (P lt; 0.05); and the density and diameter of myel inated fibers in group E were bigger than those in groups B and C (Plt; 0.05). Conclusion The tissue engineered nerve with the complex of SCs, ECM gel, bFGF-PLGA sustained release microspheres, PLGA microfilaments and permeables PDLLA catheters promote nerve regeneration and has similar effect to autograft in repair of nerve defects.
Objective To evaluate the results of operative treatment of complex acetabular fractures and to investigate its influence factors. Methods From June 2000 to August 2006, 54 patients with complex acetabular fractures were treated, including 44 males and 10 females aged 20-75 years old (average 39.1 years old). Fractures were due to traffic accidentin 40 cases, fall ing from high places in 8 cases and crush by heavy objects in 6 cases. All cases were fresh and close fractures and the time from injury to operation was 5-72 days. There were 5 cases of posterior column and posterior wall fracture, 25 of transverse and posterior wall fracture, 2 of T-type fracture, and 22 of double column fracture. During operation, Kocker- Lagenbach approach was used in 23 cases, anterior il ioinguinal approach was appl ied for 3 cases and the combination of anterior and posterior approaches was performed on 28 cases. AO reconstructive plate and screw internal fixation were used in all the cases. Results Fifty-two cases were followed up for 12-74 months (average 31.3 months). Anatomical reduction was achieved in 23 cases, satisfactory reduction in 19 cases, poor reduction in 10 cases, and the excellent and good rate reached 80.77%. During operation, 1 case suffered from a tear in the external il iac vein and healed after vein repair; 2 cases had sciatic nerve injury and took mecobalamin as oral administration, one of them fully recovered, and the other had incomplete recovery at 18-month follow-up. At the final follow-up, there were 6 cases of severe heterotopic ossification, one of them received heterotopic bone resection and the rest 5 patients received conservative treatment; there were 9 cases of traumatic osteoarthritis, one of them received total hip replacement and the rest 8 patients received conservative treatment; there were 5 cases of avascular necrosis of the femoral head, two of them received total hip replacement, 1 received no further treatment because the femoral head didn’ t collapse, and the rest 2 patients gave up total hip replacement; 75.00% patients were graded as excellent and good according to the modified Merled’Aubigné-Postel hip score system. Patients’ qual ity of l ife was compared with local population normsmatched for age and sex by using SF-36 scales, their overall score were below the local population norms, and their general health, vital ity, role l imitation due to emotional problems and mental health were comparable to the local population norms. Logistic regression analysis revealed the time to reduce hip dislocation, qual ity of fracture reduction nd traumatic arthritis were independent risk factors affecting postoperative functional outcomes. Conclusion Applying open reduction and internal fixation in the treatment of displaced complex acetabular fractures has a satisfying therapeutic effect. Time to reduce hip dislocation, qual ity of fracture reduction as well as traumatic arthritis are independent risk factors affecting postoperative functional outcomes.
Objective To develop three-dimensional (3D) porous nanofiber scaffold of PLGA-silk fibroincollagen and to investigate its cytocompatibil ity in vitro. Methods Method of electrostatic spinning was used to prepare 3D porous nanofiber scaffold of PLGA-silk fibroin-collagen (the experimental group) and 3D porous nanofiber scaffold of PLGA (the control group). The scaffold in each group was observed by scanning electron microscope (SEM). The parameters of scaffold fiber diameter, porosity, water absorption rate, and tensile strength were detected. SC harvested from the bilateral brachial plexus and sciatic nerve of 8 SD suckl ing rats of inbred strains were cultured. SC purity was detected by S-100 immunohistochemistry staining. The SCs at passage 4 (5 × 104 cells/mL) were treated with the scaffold extract of each group at a concentration of 25%, 50%, and 100%, respectively; the cells treated with DMEM served as blank control group. MTT method was used to detect absorbance (A) value 1, 3, 5, and 7 days after culture. The SC at passage 4 were seeded on the scaffold of the experimental and the control group, respectively. SEM observation was conducted 2, 4, and 6 days after co-culture, and laser scanning confocal microscope (LSCM) observation was performed 4 days after co-culture for the growth condition of SC on the scaffold. Results SEM observation: the scaffold in two groups had interconnected porous network structure; the fiber diameter in the experimental and the control group was (141 ± 9) nm and (205 ± 11) nm, respectively; the pores in the scaffold were interconnected; the porosity was 87.4% ± 1.1% and 85.3% ± 1.3%, respectively; the water absorption rate was 2 647% ± 172% and 2 593% ± 161%, respectively; the tensile strength was (0.32 ± 0.03) MPa and (0.28 ± 0.04) MPa, respectively. S-100 immunohistochemistry staining showed that the SC purity was 96.5% ± 1.3%. MTT detection: SC grew well in the different concentration groups and the control group, the absorbance (A) value increased over time, significant differences were noted among different time points in the same group (P lt; 0.05), and there was no significant difference between the different concentration groups and the blank control group at different time points (P gt; 0.05). SEM observation: in the experimental group, SC grew well on the scaffold, axon connection occurred 4 days after co-culture, the cells prol iferated massively and secreted matrix 6 days after co-culture, and the growth condition of the cells was better than the control group. The condition observed by LSCM 4 days after co-culture was the same as that of SEM. Conclusion The 3D porous nanofiber scaffoldof PLGA-silk fibroin-collagen prepared by the method of electrostatic spinning is safe, free of toxicity, and suitable for SC growth, and has good cytocompatibil ity and proper aperture and porosity. It is a potential scaffold carrier for tissue engineered nerve.