ObjectiveTo investigate the protective effects of carboxymethylated chitosan (CMCS) on oxidative stress induced apoptosis of Schwann cells (SCs), and the expressions of brain derived neurotrophic factor (BDNF) and gl ial cell line derived neurotrophic factor (GDNF) in oxidative stress induced SCs. MethodsTwenty-four 3-5 days old Sprague Dawley rats (weighing 25-30 g, male or female) were involved in this study. The bilateral sciatic nerves of rats were harvested and SCs were isolated and cultured in vitro. The purity of SCs was identified by immunofluorescence staining of S-100. SCs were treated with different concentrations of hydrogen peroxide (H2O2, 0.01, 0.10, and 1.00 mmol/L) for 3, 6, 12, and 24 hours to establ ish the apoptotic model. The cell counting kit 8 (CCK-8) and flow cytometry analysis were used to detect the cell viabil ity and apoptosis induced by H2O2, and the optimal concentration and time for the apoptotic model of SCs were determined. The 2nd passage SCs were divided into 5 groups and were treated with PBS (control), with 1.00 mmol/L H2O2, with 1.00 mmol/L H2O2+50 μg/mL CMCS, with 1.00 mmol/L H2O2+100 μg/mL CMCS, and with 1.00 mmol/L H2O2+200 μg/mL CMCS, respectively. After cultured for 24 hours, the cell viabil ity was assessed by CCK-8, cell apoptosis was detected by flow cytometry analysis, the expressions of mRNA and protein of BDNF and GDNF were detected by real-time quantitative PCR and Western blot. ResultsThe immunofluorescence staining of S-100 indicated the positive rate was more than 95%. CCK-8 and flow cytometry results showed that H2O2 can inhibit the proliferation of SCs and induce the SCs apoptosis with dose dependent manner, the effect was the most significant at 1.00 mmol/L H2O2 for 24 hours; after addition of CMCS, SCs exhibited the increased proliferation and decreased apoptosis in a dose dependent manner. Real-time quantitative PCR and Western blot analysis showed that 1.00 mmol/L H2O2 can significantly inhibit BDNF and GDNF expression in SCs when compared with control group (P<0.05), 50-200 μg/mL CMCS can reverse the oxidative stress-induced BDNF and GDNF expression in SCs in a dose dependent manner, showing significant difference compared with control group and 1.00 mmol/L H2O2 induced group (P<0.05). There were significant differences among different CMCS treated groups (P<0.05). ConclusionCMCS has the protective stress on oxidative stress induced apoptosis of SCs, and may promote the BDNF and GDNF expressions of neurotrophic factors in oxidative stress induced SCs.
ObjectiveTo investigate the feasibility of modified classification of terrible triad of the elbow and the effectiveness of treatment strategy which was chosen by modified classification results. MethodsBetween March 2007 and November 2013, 12 cases of terrible triad of the elbow were treated by operation. There were 5 males and 7 females with an average age of 37.2 years (range, 26-74 years). The mechanism of injury was falling from height in 8 cases and traffic accident in 4 cases. The time from injury to operation was 4 to 11 days (mean, 6.8 days). According to the radial head, coronoid process, olecranon, and medial and lateral collateral ligament complexes injury situation, and based on Mason classification standard and O'Driscoll criteria, the classification standard of terrible triad of the elbow was improved. According to classification results, the approach was determined. The fracture reduction and fixation were performed and soft tissue was repaired. ResultsDehiscence of incision occurred in 1 case and was cured after dressing change; primary healing was obtained in the other patients. All the cases were followed up 19-35 months (mean, 21.6 months). The X-ray films showed fracture healing at 10-17 weeks (mean 12.8 weeks). At last follow-up, the mean flexion-extension arc of the elbow was 117.9° (range, 95-135°) and the mean forearm pronation and supination were 77.1° (range, 70-85°) and 62.5° (range, 45-75°). According to Mayo elbow performance score (MEPS), the results were excellent in 4 cases, good in 5 cases, and fair in 3 cases. One patient had valgus deformity of elbow who refused radial head replacement, and 5 cases had heterotopic ossification of the elbow on the X-ray films. ConclusionThe modified classification of the terrible triad of the elbow is simple and practical, based on the damage assessment of bony structures (radial head, coronoid process, and olecranon) and the soft tissue (medial and lateral collateral ligament complexes). The modified classification can be used effectively for guiding treatment decisions.
ObjectiveTo investigate the effectiveness of Kirschner wire fixation in scapholunate joint, capitolunate joint, and lunotriquetral joint combined with bone anchor repair for the treatment of acute perilunate injury. MethodsBetween January 2007 and January 2012, 35 cases of acute perilunate injury were treated. There were 30 males and 5 females with an average age of 45.5 years (range, 32-56 years). Fractures were caused by falling from height in 18 cases, by traffic accident in 11 cases, and by fall injury in 4 cases. The time from injury to operation was 2-6 days (mean, 3.4 days). There were 23 cases of trans-scaphoid perilunate dislocation, 10 cases of perilunate dislocation, and 2 cases of trans-triangular perilunate dislocation. Associated injuries included median nerve injury in 6 cases, radius styloid fracture in 8 cases, ulnar styloid fracture in 2 cases, and distal tibial fracture in 1 case. All the patients were treated by open reduction, Herbert screw fixation of scaphoid fractures, and Kirschner wire fixation in scapholunate joint, capitolunate joint, and lunotriquetral joint, and the intercarpal ligaments were repaired by Mitek bone anchor. ResultsSuperficial wound infection occurred in 2 cases, and primary healing of incision obtained in others. Thirty-five patients were followed up 12-35 months (mean, 18 months). X-ray films showed fracture union in 21 cases of scaphoid fractures, and bone nonunion in 2 cases of scaphoid fractures. During the follow-up period, there was no avascular necrosis of scaphoid or lunate. At last follow-up, the scapholunate angle, radiolunate angle, and wrist range of motion (ROM) in extension had no significant difference between affected and unaffected sides (P > 0.05). The wrist ROM in flexion and grip strength of affected side were not up to the levels of unaffected side (P < 0.05). According to the modified Mayo wrist scoring system, the score was 79.9±10.7, which were excellent in 8 cases, good in 17 cases, fair in 7 cases, and poor in 3 cases, and the excellent and good rate was 71.4%. The disability of arm-shoulder-hand (DASH) questionnaires score was 21±10. Traumatic osteoarthritis was observed in 2 cases. ConclusionKirschner wire fixation in scapholunate joint, capitolunate joint, and lunotriquetral joint combined with bone anchor repair for the treatment of acute perilunate injury can get early stability of the carpal joint, favorable intercarpal ligament repair, and good recovery of wrist joint function.