BACKGROUND: FG loop (FGL) is a core active peptide fragment of neural cell adhesion molecule (NCAM), which can directly act on fibroblast growth factor receptor 1 (FGFR1) to activate NCAM signal pathway.OBJECTIVE: To observe the effects of synthetic peptides FGL on PC12 cells proliferation and apoptosis.METHODS: ①PC12 cells proliferation and apoptosis: The cultured PC12 cells were divided into control group and experiment group. The experimental group was added with 1% FGL peptide solution. The control group was pre-coated with poly-lysine plates. The cells were cultured 1, 3, 5, 7, 9 d respectively to detect cell proliferation by using Cell Counting Kit-8. ②PC12 apoptosis and nuclear factor kappa B mRNA detection: The PC12 cells were divided into normal group, experimental group and injury group. H2O2 was added into the injury group for 16 hours stimulation. In the experimental group, H2O2 and FGL were used for 16 hours stimulation. The cell apoptosis were detected by flow cytometry; mRNA expression of nuclear factor kappa B was detected by quantitative fluorescent polymerase chain reaction.RESULTS AND CONCLUSION: PC12 cells cocultured with FGL peptide grow well, which indicates that FGL peptides can promote PC12 cell proliferation and inhibit PC12 cell apoptosis, as well as decrease mRNA expression of nuclear factor kappa B.

Objective To investigate the clinical outcomes of trans-facet joints approach to treat thoracic degenerative disease with anterior compression.Methods From January 2003 to December 2009,22 patients with thoracic myelopathy caused by anterior compression were studied retrospectively.The patients included 16 males and 6 females,aged from 36 to 72 years(average 54.2 years).There were thoracic ossification of posterior longitudinal ligament(OPLL)in 11 cases,thoracic disc protrusion with ossification in 8 cases,thoracic vertebra posterior osteophytes in 2 cases,ankylosing spondylitis with thoracic pseudoarthrosis in 1 cases.Preoperative Japanese Orthopaedic Association(JOA)score was 5.2(range,2-9).The characteristic of thoracic degeneration was analyzed by CT and MRI examination.Posterior decompressive laminectomies were performed by the technique of "cap uncovering".The facet joints were removed bilaterally.Anterior ossified compressions were cut via posterior-lateral approach,and then intervertebral bone graft and bilateral pedicle screws were implanted.Results All patients were followed up for 8 to 38 months.According to the revised Epstein standard,there were excellent in 7 patients,good in 9,fair in 4,and poor in 2.The total effective rate was 90.9%(20/22).The excellent and good rate was 72.7%(16/22).The mean postoperative JOA score was 8.7(range,2-11).Surgical complications included dural laceration in 1 patient,pleura injury in 1 patient,epidural hematoma in 2 patients.There were no cases of spinal instability or deep infection.Conclusion The anterior compression can be solved completely via trans-facet joints approach in thoracic degenerative disease patients.

Objective To investigate the risk factors and preventive measures for acute epidural hematoma after posterior thoracic spine surgery.Methods A retrospective study of 14 patients who developed acute epidural hematoma after thoracic spine surgery from May 2002 to May 2012 was conducted.There were 6 males and 8 females,aged from 41 to 69 years (average,61.2 years).There were 10 cases of thoracic spinal canal stenosis,3 cases of thoracic spinal meningioma,and 1 case of thoracic metastasis.About 3-14 h (average,6.6 h) after posterior thoracic spine surgery,the neurological deterioration was found,and according to the American Spinal Injury Association (ASIA) classification,there were 5 cases of grade A and 9 cases of grade B.The neurological function before evacuation of hematoma was compared with that after evacuation of hematoma and that at final follow-up.The correlations between hematoma compression time,neurological improvement rate and neurological function before evacuation of hematoma were statistically analyzed.Results After evacuation of hematoma,the ASIA classification of 14 patients was as follows:grade B in 1 case,grade C in 2 cases,grade D in 4 cases,and grade E in 7 cases.The hematoma compression time of 3 patients with grade B or C was more than 10 hours.Obvious difference of neurological function was found before and after evacuation of hematoma.The neurological improvement rate was 63.7％±23.3％ after evacuation of hematoma,which was negatively correlated with hematoma compression time and positively correlated with preoperative neurological function.The neurological function before evacuation of hematoma was significantly different from that at final follow-up.The neurological improvement rate was 86.97％±17.58％ at final follow-up,which was negatively correlated with hematoma compression time and positively correlated with preoperative neurological function.Conclusion The acute epidural hematoma after thoracic spine surgery could cause severe neurological deterioration.The neurological improvement was negatively correlated with hematoma compression time.Evacuation of hematoma must be done as soon as possible once progressive neurological deterioration is found.

BACKGROUND:Inhibiting the apoptosis of intervertebral disc cel s can postpone the degenerative process of intervertebral disc. Survivin has a strong function of regulating cel proliferation and anti-apoptosis.
OBJECTIVE:To construct and identify the lentiviral vector encoding survivin gene of human.
METHODS:The survivin gene of human (BIRC5) was synthesized through the gene synthesis technology, amplified by PCR and analyzed by electrophoresis. The target gene was cloned into lentiviral expression plasmid to obtain the recombinant lentiviral vector Lenti-BIRC5. After transformation into competent E. coli cel s, the candidate clones were identified by PCR firstly. The positive clones were identified by gene sequencing. The lentivirus plasmid containing target gene was transfected into 293T cel s, and the expression of recombinant lentiviral vector Flag-Survivin fusion protein was detected through western blot analysis.
RESULTS AND CONCLUSION:The PCR results of electrophoresis and DNA sequencing showed that lentiviral vector containing human survivin gene was constructed successful y. Western blot analysis results showed that the target gene was transfected successful y and over-expressed in cultured cel s. The lentiviral expression vector of human survivin gene Lenti-BIRC5 was constructed successful y, which lays a foundation for the study addressing the anti-apoptotic effects of survivin on human nucleus pulposus cel s.

Objective To investigate the vascular endothelial growth factor (VEGF) expression level by chondrocytes isolated from patients with osteoarthritis (OA) in hip or femoral neck fracture (FNF) and explore the effect of synovial fluid from OA or FNF on secretion of VEGF. Methods The cartilage tissues were collected from 12 patients with OA in hip and 8 patients with FNF. Cartilage was stained with HIM and Safranin O/Fast Green (S/F) method. The damage of cartilage was evaluated using Mankin scores.Cathepsin B which was selected for cell dedifferentiation monitoring marker and VEGF level was detected in the supernatant fluid. The synovial fluid from OA, FNF and DMEM were respectively added to the culture medium to explore their effects on regulating VEGF. Results Cartilage the Mankin scores of OA group were higher than that of FNF group. Chondrocytes gradually lost their original spherical appearance, with Cathepsin B upregulated while VEGF downregulated. The OA synovial fluid can stimulate chongdrocytes to secrete more VEGF than the one from patients with FNF. However, chondrocytes gradually produced less VEGF after passaging. Conclusion Mankin scores had good correlation with chondrocytes' VEGF production in the early stage of primary culture. Chondrocytes showed quick dedifferentiation characteristics in vitro. OA synovial fluid showed abig ger capability in stimulating chondrocytes to express more VEGF, which might indicate that OA synovial fluid participated in the pathological process of OA.

BACKGROUND:Restoration of neurological functions after the damaged peripheral nerve is reconstructed is a hot topic in existing research. Within a short term fol owing peripheral nerve injury, nerve and muscle begin to develop irreversible degeneration. Restoration of the damaged nerve requires delayed degeneration and basic microenvironment. OBJECTIVE:To investigate the protective effect of cardiotrophin-1 on PC12 cells and Schwann cells. METHODS:Schwann cells and PC12 cells were obtained and cultured in complete medium, serum-free medium and 50 ℃ medium, respectively. cells in cardiotrophin-1 group were treated with exogenous cardiotrophin-1 solvent, while those in the control group were treated with equivalent Dulbecco’s modified Eagle’s medium, for 24 hours. The survival rate for PC12 cells and Schwann cells was determined using cellCounting Kit-8 colorimetric method. The lactate dehydrogenase activity in supernatant was detected by lactate dehydrogenase kit, and the malondialdehyde content and superoxide dismutase activity were measured by thiobarbituricaicd and xanthine oxidese method respectively. RESULTS AND CONCLUSION:The survival rate of PC12 cells and Schwann cells in cardiotrophin-1 group was obviously increased, lactate dehydrogenase releasing and malondialdehyde content were obviously decreased, superoxide dismutase activity was dramatical y improved compared with control group. Exogenous cardiotrophin-1 reduces the injury caused by ischemia and heat stress stimulation for PC12 cells and Schwann cells. The mechanism of protection may be related to the expression of anti-apoptosis protein activated by the combination of cardiotrophin-1 and its receptors.

Lateral approach percutaneous spinal endoscopy， one of the most representative spinal endoscopic procedures， has ranked among the mainstream spinal operations that are facilitated to be understood and mastered by surgeons. The surgeries possess advantages of precise curative effect and wide scope of application after a series of conceptual innovations and reforms including YESS technology， TESSYS technology， eccentric trepan technology， visualized plasty technology， full-endoscopic visualization technology， and spinal endoscopy technology from the perspective of open surgery. Moreover， lateral approach percutaneous spinal endoscopy has formed a technology cluster that is inclusive with broad development prospects based on the introduction of high-tech technologies such as artificial intelligence and various navigation technologies.

ObjectiveTo investigate the clinical features and treatment of ascending paralysis after thoracolumbar fracture.MethodsThree male patients with 2 fracture levels at T12 and one at L1 were retrospectively studied.Their mean age was 41.3 years(range,39-42 years).All 3 cases were undertaken open decompression,reduction and internal fixation.Paralysis level began to ascend at 2-5 days after injury,with 2 cases up to C2,3 and 1 case up to T7.Two patients suffered irritating pain over the paralysis level before onset of ascending.Postoperative MRI images demonstrated well reduction and no compression of spinal cord.In the early phase after ascending,MRI obviously showed swelling in spinal cord and long T1 and long T2 signals shaped patchy and stripy distribution in the central area.One patient's MRI displayed that the spinal cord shrinked 16 days after trauma with abnormal high signal in the central area.ResultsTwo cases died of respiratory muscle paralysis and 1 case suffered paraplegia with no recovery 5 years after surgery.ConclusionAscending paralysis after thoracolumbar fracture is a rare complication with very poor prognosis.MRI is available for evaluating operational effects and affected level.The exact mechanism and effective treatment are still unclear and need further investigated.

BACKGROUNDThe objective of this study was to use three-dimensional finite element (FE) models to analyze the stability and the biomechanics of two upper cervical fixation methods: the C2 intralaminar screw method and the C2 pedicle screw method.

METHODSFrom computed tomography images, a nonlinear three-dimensional FE model from C0 (occiput) to C3 was developed with anatomic detail. The C2 intralaminar screw and the C2 pedicle screw systems were added to the model, in parallel to establish the interlaminar model and the pedicle model. The two models were operated with all possible states of motion and physiological loads to simulate normal movement.

RESULTSBoth the C2 intralaminar screw method and the C2 pedicle screw method significantly reduced motion compared with the intact model. There were no statistically significant differences between the two methods. The Von Mises stresses of the internal and external laminar walls were similar between the two methods. Stability was also similar.

CONCLUSIONSThe C2 intralaminar screw method can complement but cannot completely replace the C2 pedicle screw method. Clinicians would need to assess and decide which approach to adopt for the best therapeutic effect.

【Objective】 Compare the early outcome and safety of endoscopy-unilateral laminectomy for bilateral decompression （Endo-ULBD） and posterior lumbar interbody fusion （PLIF） in the treatment of multi-segment lumbar central spinal stenosis. 【Methods】 We retrospectively analyzed 68 patients with multi-segment central lumbar spinal stenosis treated between October 2019 and October 2020 in the Department of Spine Surgery， Affiliated Hospital of Qingdao University. Of them 33 patients were treated with Endo-ULBD and 35 ones were treated with PLIF. We compared the operation time， times of intraoperative fluoroscopy， estimated intraoperative blood loss， incision length， postoperative time to get out of bed， postoperative hospital duration， complications， visual analogue scale （VAS）， Oswestry dysfunction index （ODI） score before and 1 day， 1 month， and 3 months after operation， Japanese Orthopedic Association Assessment Treatment Score （JOA）， and modified MacNab score 3 months after operation between the two groups of patients. 【Results】 Compared with PLIF group， Endo-ULBD group had significantly shorter operation time， smaller incision length， less intraoperative blood loss， shorter postoperative bed time and postoperative hospital stay， and fewer surgical complications （all P<0.05）. There was significantly more intraoperative fluoroscopy in Endo-ULBD group than in PLIF group （P<0.05）. The VAS， ODI and JOA scores of the two groups were significantly improved after treatment （P<0.05）. There was no statistical difference in VAS of leg pain between the two groups after treatment （P>0.05）. However， after treatment Endo-ULBD group outperformed PLIF group in lower back pain VAS， ODI， JOA and the 3-month follow-up excellent and good rates （P<0.05）. 【Conclusion】 For patients with multi-segment central lumbar spinal stenosis， Endo-ULBD treatment can achieve better early clinical outcome than PLIF surgery， with less bleeding， shorter operation time， faster postoperative recovery， and fewer complications.