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Objective To observe biomechanical characteristics and advantages of the self-developed anatomical locking plate of sternoclavicular joint by comparison with the radial distal oblique T-shaped locking plate and sternoclavicular hook plate. Methods Nine embalming and moistening adult corpses were selected, including 6 males and 3 females. Model of complete dislocation of the sternoclavicular joint caused by complete removal of the sternoclavicular joint specimen. The bilateral sternoclavicular joints of 9 specimen models were randomly numbered, matched and divided into Group A(experimental group, sternoclavicular joint anatomical locking plate), Group B(control group 1, the radial distal oblique T-shaped locking plate) and Group C(control group 2, sternoclavicular hook plate), with 6 sternoclavicular joints in each group. All specimens were placed with steel plates on both sides and fixed on the universal mechanical test machine. Three biomechanical experiments were carried out, including loading of distal clavicle, torsion of distal clavicle and anti-pull out of sternum handle screw. Results Distal clavicle loading test: the load-displacement of specimens in three groups showed a linear relationship. The compressive deformation resistance in experimental group was stronger than that in two control groups. Distal clavicle torsion test: the relationship between torque and torsion angle was linear. The torsional deformation resistance in experimental group was stronger than that in two control groups. Anti-pullout test of sternum handle screw: there was a significant difference in the maximum anti-pullout force of sternum handle screw among the three groups (P＜0.05). The anti-pullout performance of the sternum handle screw in the experimental group was better than that in the two control groups. Conclusions The self-developed sternoclavicular joint anatomical locking plate is superior to the oblique T-shaped locking plate of distal radius and the plate of sternoclavicular hook in terms of anti-compression, anti-torsion and anti-pullout of sternoclavicular screw, so as to provide an ideal internal fixation device for the treatment of fracture and dislocation of sternoclavicular joint.
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Methods: A new type of anatomical locking plate for sternoclavicular joint was developed, which accorded with the anatomical features and biomechanical characteristics of Chinese sternoclavicular joint. By adopting the method of clinical randomized controlled study, 32 patients with the sternoclavicular joint fracture and dislocation who met the selection criteria between June 2008 and May 2015 were randomly divided into groups A and B ( n=16), and the patients were treated with new anatomic locking plate and distal radial T locking plate internal fixation, respectively. There was no significant difference between 2 groups in gender, age, injured side, body mass index, cause of injury, type of injury, the time from injury to operation, and preoperative Rockwood grading score ( P>0.05). The operation time, intraoperative blood loss, incision length, hospitalization time, and postoperative complications in 2 groups were recorded, and the effectiveness was evaluated by Rockwood grading score.
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BACKGROUND:Acellular nerve scaffolds have the three-dimensional structure of natural nerves and low immunogenicity,but their effect on long nerve defects is still not ideal.Therefore,it is necessary to construct tissueengineered nerve using acellular nerve and seed cells in order to improve the therapeutic effect.OBJECTIVE:To systemically review the efficacy of combination of acellular nerve grafts (ANGs) and mesenchymal stem cells (MSCs) or Schwann cells (SCs) transplantation in the treatment of sciatic nerve defects in a rat model.METHODS:Randomized controlled trials (RCTs) about the effects of combination of ANGs and MSCs or SCs transplantation for sciatic nerve defects in rats were searched in PubMed,The Cochrane Library,EMbase,CNKI,WanFang and VIP from inception to July 2016.Three reviewers independently screened literature according to the inclusion and exclusion criteria,extracted data,and assessed the risk of bias of included studies.Then,a Meta-analysis was performed using Review Manger5.3 software.RESULTS AND CONCLUSION:A total of 10 RCTs involving 252 rats were included.The results of meta-analysis showed that:compared with the control group (simple acellular nerve scaffold group),the sciatic functional index (SFI) of the combined group (combination of ANGs and MSCs or SCs transplantation) were superior at 2 weeks [SMD=2.73,95％ CI (1.92,3.45),P ＜ 0.000 01],4 weeks [SMD=4.57,95％ CI (3.43,5.70),P ＜ 0.000 01],6 weeks [SMD=1.62,95％CI (0.18,3.06),P=-0.03],8 weeks [SMD=4.90,95％ CI (2.96,6.84),P ＜ 0.000 01] after surgery.The nerve conduction velocity [SMD=1.39,95％ CI (0.99,1.78),P ＜ 0.000 01),latency period (MD=-0.98,95％ CI (-1.19,-0.76),P ＜ 0.000 01],and amplitude [SMD=1.23,95％ CI (0.62,1.85),P ＜ 0.000 1] were superior at 12 weeks after surgery.The myelin sheath thickness was superior at 8 weeks [MD=0.14,95％ CI (0.07,0.21),P ＜ 0.000 1],12 weeks [SMD=1.85,95％ CI (1.63,2.08),P ＜ 0.000 01] and the number of myelinated nerve fibers were superior at 12 weeks [SMD=3.59,95％CI (2.63,4.55),P ＜ 0.000 01] after surgery.The gastrocnemius wet weight was superior at 8 weeks after surgery [SMD=4.22,95％ CI (2.40,6.03),P ＜ 0.000 01].Current evidence indicates that the combination of ANGs and MSCs or SCs can promote the regeneration and functional recovery of the peripheral nerve.Due to the limited quality of the included studies,the above conclusion should be verified by conducting high-quality and large-scale RCTs.
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[Objective] To explore the effects of rifampicin on cell morphology,intracellular reactive oxygen species (ROS),reduced glutathione (GSH),and cell apoptosis in rotenone-induced differentiated pheochromocytoma (PC12) cells.[Methods] Rotenone was added in rat PC12 cells to develop a model of Parkinson's disease in vitro.Cell morphology was observed by microscope.Intracellular GSH was determined by a microplate reader.The intracellular ROS and the apoptosis rate were measured by flow cytometry.[Results] Compared with control group and rifampicin control group,GSH significantly decreased but ROS and apoptosis rate significantly increased in rotenone group.Compared with rotenone group,GSH significantly increased but ROS and apoptosis rate significantly decreased in a dose-dependent manner in rifampicin control group (100,200,and 300 μmol/L).[Conclusion] Rifampicin may reduce the damage of rotenone-induced differentiated PC12 cells through inhibiting oxidative injury in a dose-dependent manner.