BACKGROUND:The effect of anterior controllable anteriodisplacement and fusion on the biomechanics of cervical spine is still unclear.Previous studies have majorly focused on surgical techniques,the medium-and long-term efficacy,and postoperative complications of anterior controllable anteriodisplacement and fusion. OBJECTIVE:To analyze the biomechanical effects of anterior controllable anteriodisplacement and fusion on vertebrae-ossification of posterior longitudinal ligament complex and implants of the cervical spine using finite element method. METHODS:A healthy male volunteer was recruited for CT scanning of the entire cervical spine.Using the finite element analysis software,a normal whole cervical spine model was constructed and its validity was verified by comparison with the previous articles.Subsequently,a preoperative model of continuous posterior longitudinal ligament ossification involving C4,C5,and C6 was constructed.Based on the preoperative model,a three-dimensional finite element model of anterior controllable anteriodisplacement and fusion was created.After constrain of the lower surface of the C7 vertebral body of the two models,an axial force of 50 N and a moment of 1.0 N·m were applied to the upper surface of the C1 cone body.Under forward flexion,posterior extension,left/right bending,and left/right rotation conditions,the effects of anterior controllable anteriodisplacement and fusion on vertebrae-ossification of posterior longitudinal ligament complex and implants were further analyzed. RESULTS AND CONCLUSION:(1)From the preoperative model,it was found that the ossification stress was mainly concentrated in the C4/5 segment;the maximum stresses of vertebrae-ossification of posterior longitudinal ligament complex under the conditions of forward flexion,posterior extension,left bending,right bending,left rotation and right rotation were 10.1,148.6,68.9,74.8,83.8,and 85.1 MPa,respectively.(2)After anterior controllable anteriodisplacement and fusion,the distribution area of stress concentration at the vertebrae-ossification of posterior longitudinal ligament complex did not change significantly,but the values were decreased obviously;in addition to the increase of stress(+44.7%)in the anterior flexion at the surgical model of anterior controllable anteriodisplacement and fusion,when compared with the preoperative one,the anterior controllable anteriodisplacement and fusion stress was significantly lower than that in the preoperative model under the other five working conditions,in which the value was decreased by-74.1%at the posterior extension position.Under the left bending,right bending,left rotation and right rotation,the ossification stress was decreased by 62.2%,63.3%,66.4%,and 67.9%,respectively.(3)The stress of titanium plate and screw was mainly concentrated at the both ends;the largest posterior extension stress was 149.5 MPa while the smallest forward flexion stress was 43.3 MPa.The stress of the four intervertebral cages was mainly concentrated at the C3/4 and C6/7 ones;and the stress was mainly distributed around the upper and lower surfaces of the fusion device,its value ranging from 30.8 MPa(the largest extension stress)to 11.5 MPa(the lowest forward flexion stress).The stress of the implants(titanium plate,screw,and intervertebral cage)was mainly concentrated at the two ends with the largest values,which would lead to the fracture of the titanium plate screw and the loosening of the screws.(4)In conclusion,anterior controllable anteriodisplacement and fusion was able to significantly reduce the stress of vertebrae-ossification of posterior longitudinal ligament complex,and may help prevent excessive proliferation and compression of nerves.After surgery,much attention should be paid to the occurrence of loosening of the screws,or displacement and fracture of titanium plates at the both ends.

OBJECTIVE： To study the effect mechanism of iridoid glycosides extracted from Scrophularia ningpoensis inhibiting cardiomyocytes apoptosis in myocardial infarction model rats. METHODS： The male Wistar rats were randomly divided into sham operation group， model group and S. ningpoensis iridoid glycosides low-dose， medium-dose and high-dose groups， with 10 rats in each group. Myocardial infarction models were established by ligating the left anterior descending coronary artery of the rats， and sham operation group was only threaded without ligation. After the model was established， each administration group was given S. ningpoensis iridoid glycosides suspension intragastrically at three different doses of 50，100，200 mg/kg （by the amount of total glycosides extract） with 10 mL/time， twice a day， for consecutive 7 days. Sham operation group and model group were given constant volume of normal saline intragastrically with same method. The changes of S-T segment of lead ECG Ⅱ were recorded before， after and during 7 days of administration. Cardiac function of rats was examined. The serum levels of LDH， CK-MB， cTnⅠ， NT-pro BNP and TNF-α were determined by colorimetry， immunosuppression or ELISA. The apoptosis of myocardial cells was observed by TUNEL method. SOD activity and MDA content in cardiac myocytes were detected by colorimetry. The expressions of Bcl-2， Bax， Cyt C， Caspase-8， Caspase-9， Caspase-12， Caspase-3 and Calpain in cardiac myocytes were detected by ELISA， enzymolysis colorimetry or enzymatic fluorescence assay. RESULTS： Compared with sham operation， electrocardiogram S-T segment was significantly elevated and the left ventricular end-diastolic diameter and left ventricular end-systolic diameter were significantly increased in the model group； left ventricular ejection fraction and short axis shortening rate decreased significantly； serum levels of LDH， CK-MB， cTnⅠ， NT-pro BNP and TNF-α were increased significantly； there were a large number of yellow-brown apoptotic cells in myocardial tissue； the activity of SOD in myocardial tissue was significantly decreased while the content of MDA was significantly increased； the protein expression level of Bcl-2 and Bcl-2/Bax were significantly decreased， while the levels of Bax， Cyt C， Caspase-3， Caspase-8， Caspase-9， Caspase-12 and Calpain were significantly increased （P＜0.05 or P＜0.01）. Compared with model group， above indexes and pathological changes of myocardial tissue were improved significantly in administration group； the level of Bcl-2 and Bcl-2/Bax in cardiomyocytes increased significantly， while the levels of Bax， Cyt C， Caspase-3， Caspase-8， Caspase-9， Caspase-12 and Calpain decreased significantly （P＜0.05 or P＜0.01）. CONCLUSIONS： S. ningpoensis iridoid glycosides can inhibit the activation of Caspase-3 by inhibiting three apoptotic pathways related to Caspase-8， Caspase-9 and Caspase-12， and then inhibit the apoptosis of cardiomyocytes.

Objective To explore the treatment method and clinical effect of congenital scoliosis caused by lumbosacral spine deformity in children.Methods From October 2000 to October 2015,a consecutive series of 21 congenital scoliosis due to lumbosacral spine deformity were treated in Department of Pediatric Orthopedics,the Third Affiliated Hospital of Zhengzhou University,including 12 male and 9 female,and the age was (63.1±47.3) months(3-144 months).The hemivertebrae,bone bridge,and the mixed type were found in 18 cases,2 cases,and 1 case,respectively.Hemivertebraes were on the left in 10 cases,on the right in 9 cases;involved L5 in 8 cases,S1 in 6 cases,multiple vertebrae malformation in 4 cases,wedged-shaped vertebrae involved L5 associated with contralateral bar in 1 case,unilateral unsegmented bar from L4 to S1 in 1 case,from L2 to L5 in 1 case.There were 4 cases combining with thoracic hemivertebrae,3 cases with ribs fusion and contralateral bar,16 cases(76%) with spinal cord malformations,3 cases(17%) with urinary system malformations,no congenital heart malformation.All the 21 patients were operated with one-stage posterior approach.Compared the scoliosis Cobb angle,trunk shift,operative time,blood loss volume,and complications among preoperation,post-operation and final follow-up.Results In this study,operative time was (278.9±83.1) min,blood loss volume was (355.3±249.0) mL,follow-up was (5.1±2.7) years.There were 18 cases operated with pedicle screw fixation,aged (72.9±44.1) months(16-144 months),operative time was (296.2±74.2) min,blood loss volume was(422.1±238.2) mL;the mean coronal Cobb angle of malformation area at preoperation,post operation and the final follow-up were(27.3±10.2)°,(11.0±5.9)°,(9.8±4.2)°,while the correction rate of post-operation and the final follow-up were 59.7%,64.1%.There were 3 cases operated by hemivenebra resection without pedicle screw fixation,aged 7.7 months(3-15 months),operative time was 168.3 min,blood loss volume was 103.3 mL.The mean coronal Cobb angle of malformation area at preoperation,post-operation and the final follow-up were 26.0°,13.6°,12.5°,while the correction rate of post-operation and the final follow-up were 47.7%,51.9%.The follow-up period was (5.1±2.7) years.The coronal Cobb angle of lumbosacral curve at preo-peration,post-operation and the final follow-up were (27.7±10.0)°,(11.3±5.4)°,(10.0±5.0)°,compared with preoperation,the differences of post-operation and the final follow-up were statistically significant (t=6.600,7.230,all P<0.05),with the correction rate of 59.2%,63.9%;the compensatory head side Cobb angle were(25.0±12.8)°,(11.9±8.2)°,(10.3±6.9)°,compared with preoperation,the differences of post-operation and the final follow-up were statistically significant (t=3.934,4.626,all P<0.05),with the correction rate of 52.4%,58.8%.Trunk shift was significantly improved.One case appeared fracture fixation rods breakage after 9 years,1 case appeared iliac screw breakage after 2 years but no complication such as infection,nerve injury.Conclusions The formation of obstacles and vertebral segmentation defects will lead to lumbosacral spine deformity,and scoliosis.Early one-stage posterior hemivertebra resection,breakage the bone bridge combined with pedicle screw fixation can obtain satisfactory clinical outcome.

OBJECTIVE:To establish the pharmacokinetic-pharmacodynamic(PK-PD) model of Nisoldipine controlled-release patches(NCRP)in spontaneously hypertensive rats(SHR). METHODS:SHR were randomized into a patch(NCRP)group and a tablet(Nisoldipine tablets)group,with 6 rats in each group. The microdialysis probes were implanted in SHR. Each rat was given 5 mg nisoldipine. Plasma microdialysate was collected within 36 h after administration. HPLC was adopted to determine the plasma concentration of nisoldipine,and WinNonlin 5.3 was employed to calculate Pharmacokinetic parameters. With heart rate and blood pressure as pharmacodynamic indexes,PK-PD model study was conducted. RESULTS:Vs. nisoldipine tablets,NCRP has con-trolled release effect. The relationship between NCRP drug effect and effect-site concentration met the Sigmoid-Emax model. The main parameters of the PK-PD model for heart rate and systolic blood pressure were as follows as Emax of (2.65 ± 0.06) and (10.71 ± 0.87),EC50 of (83.65 ± 35.25) and (1.29 ± 0.26) ng/ml,γ of (0.83 ± 0.91) and (1.2 ± 0.35),Keo of (0.37 ± 0.53) and (0.91±0.24)h-1. CONCLUSIONS:PK-PD model of NCRP in SHR has been established successfully.