BACKGROUND:Previous studies have found that neuronal damage caused by continuous excessive fluoride exposure is related to Ca2+overload,but the mechanism of Ca2+flow conversion between intracellular calcium stores and cell apoptosis damage is still unclear.OBJECTIVE:To investigate the effect of fluoride exposure on Ca2+transport channel proteins and apoptosis levels in the mitochondria-associated endoplasmic reticulum membrane of primary cultured neural cells.METHODS:Primary nerve cells of neonatal SD rats were cultured in vitro and identified by immunofluorescence staining with neuronal nucleus-specific antibody up to day 7.The nerve cells were divided into control group(containing 0 mmol/L sodium fluoride),low fluoride group(containing 0.5 mmol/L sodium fluoride),and high fluoride group(containing 1 mmol/L sodium fluoride).The cell morphological changes were observed by light microscope 24 hours after fluorine exposure.The expression levels of apoptosis-related protein BAX/BCL-2 and calcium transfer-related pathways VDAC1,GRP 75,and IP3R were detected using western blot assay.The expression levels of VDAC1,GRP 75,and IP3R mRNA were detected by RT-PCR.Ca2+levels were detected by Rhood-2AM Ca2+probe.Mitochondrial membrane potential detection kit was used to detect the change in mitochondrial membrane potential.The level of apoptosis was determined by flow cytometry and TUNEL staining.RESULTS AND CONCLUSION:(1)The purity of neurons cultured on day 7 had been determined to be over 90％,with few impurities,good growth status,and tight cell network connections,meeting the requirements of subsequent experiments.(2)Compared with the control group,growth of neural cell clusters in the low-fluoride group and the high-fluoride group increased;the processes were broken;the cell body was rounded,and the connection network between cells was destroyed.Compared with the low-fluoride group,the cell damage changes in the high-fluoride group were more obvious.(3)Compared with the control group,the protein expressions of VDAC1,GRP75,and IP3R were increased in the low-fluoride group and the high-fluoride group(P＜0.05),and the ratio of apoptosis-related protein BAX/BCL-2 was increased(P＜0.05).Compared with the control group,the expression of VDAC1 and GRP75 mRNA in the low-fluoride group was significantly increased(P＜0.05);the expression levels of VDAC1,GRP75,and IP3R mRNA in the high-fluoride group were significantly increased(P＜0.01).(4)The level of cell apoptosis increased significantly after fluoride exposure,and the high-fluoride group was significantly higher than the control and low-fluoride groups(P＜0.01).(5)After fluoride exposure,the concentration of mitochondrial Ca2+in nerve cells increased significantly(P＜0.05),the mitochondrial membrane potential decreased(P＜0.01),and the degree of damage in the high-fluoride group was more obvious(P＜0.05).The results show that fluoride exposure impairs the morphological structure of primary neural cells,resulting in upregulation of Ca2+transfer pathway protein expression between the endoplasmic reticulum and mitochondria,mitochondrial Ca2+overload,mitochondrial damage,and increased levels of apoptosis.

BACKGROUND:Macrophage polarization plays a key role in chronic inflammatory joint diseases such as rheumatoid arthritis.Cerium dioxide(CeO2)nanoparticles have a wide range of biomedical applications such as modulating the local inflammatory microenvironment of tissues.OBJECTIVE:To investigate the role of CeO2 nanoparticles on macrophage polarization and inflammatory factor expression,as well as inflammatory modulation in a co-culture system of macrophages and fibroblasts.METHODS:(1)CeO2 nanoparticles were dispersed and observed morphologically by transmission electron microscopy.(2)Human leukemia monocytes(THP-1)were induced to differentiate and establish the M1 macrophage pro-inflammatory cell model of rheumatoid arthritis.The cells were divided into M0 group(undifferentiated macrophages),M1 group(successful macrophage modeling),CeO2 nanoparticle treatment group(M1 group with CeO2 nanoparticle treatment),and dexamethasone control group(M1 group with dexamethasone treatment)and incubated for 48 hours.The effects of CeO2 nanoparticles on the expression of inflammatory factors(endogenous nitric oxide synthase,CD86,CD80)in M1 macrophages and M1 macrophage phenotype(CD80,CD206)were detected by RT-qPCR,western blot assay,and flow cytometry.(3)A co-culture system of macrophages and fibroblasts was established,and CeO2 nanoparticles acted on the upper macrophages.The regulation of CeO2 nanoparticles on the expression of inflammatory factors(interleukin-6,tumor necrosis factor-α,cyclooxygenase-2,and endogenous nitric oxide synthase)of fibroblasts in the co-culture system was observed at the mRNA and protein levels.RESULTS AND CONCLUSION:(1)Transmission electron microscopy showed that the diameter of CeO2 nanoparticles was(19.5±2.0)nm.(2)Compared with the M0 group,the mRNA of endogenous nitric oxide synthase and CD86,and the protein expression of endogenous nitric oxide synthase and CD80 in the M1 group were upregulated.Compared with the M1 group,the mRNA expression of endogenous nitric oxide synthase and CD86,and the protein expression of endogenous nitric oxide synthase and CD80 in the CeO2 nanoparticle treatment group were downregulated.Flow cytometry showed that 20 nm CeO2 nanoparticles downregulated the number of M1 macrophages.(3)Compared with the M1 group,20 nm CeO2 nanoparticles downregulated the mRNA and protein expression of inflammatory factors(tumor necrosis factor α,interleukin 6,cyclooxygenase 2,and endogenous nitric oxide synthase)in the co-culture system HFL1 cells.(4)The results showed that 20 nm CeO2 nanoparticles can alleviate inflammation in the co-culture system by inhibiting the expression of pro-inflammatory factors in M1 macrophages,providing a new idea for the treatment of inflammatory diseases such as rheumatoid arthritis.

BACKGROUND:Radiotherapy significantly improves survival rates in patients with various malignant tumors.However,with prolonged post-treatment survival,many patients face the risk of radiation-related cardiac toxicity.This is especially true after chest radiotherapy,where the risk of radiation-induced heart disease significantly increases,becoming one of the most severe complications affecting prognosis survival.OBJECTIVE:To identify diagnostic markers of endothelial cellular senescence in radiation-induced heart disease through systematic transcriptomic analysis.METHODS:Firstly,genes associated with cellular senescence were screened from the CellAge database and intersected with the transcriptomic training dataset of a mouse model of radiation-induced heart disease to identify differentially expressed senescence-related genes.Secondly,weighted gene co-expression network analysis and machine learning were used to identify key hub genes that play critical roles in radiation-induced heart disease.The expression of these genes was validated using a dataset of radiation-induced endothelial injury.Additionally,the quanTlseq method was employed to assess the immune infiltration status related to radiation-induced heart disease.The expression levels of key genes and their association with survival in esophageal squamous cell carcinoma patients receiving chest radiotherapy were explored through the analysis of The Cancer Genome Atlas database.RESULTS AND CONCLUSION:(1)Systematic transcriptomic analysis identified CCND1 as the core gene of endothelial cellular senescence in radiation-induced heart disease,and this finding was validated in the mouse model of radiation-induced heart disease.(2)The diagnostic model constructed from these data indicated that CCND1 had high specificity and sensitivity for diagnosing radiation-induced heart disease.(3)Immune infiltration analysis revealed significant immune response dysregulation in the mouse model of radiation-induced heart disease,and CCND1 was closely related to various immune cells.(4)Kaplan-Meier survival analysis showed that CCND1 was associated with poorer disease-specific survival in esophageal squamous cell carcinoma patients receiving chest radiotherapy.This study systematically uncovers,for the first time,the pivotal role of CCND1 in endothelial cell senescence associated with radiation-induced heart disease.CCND1,a gene integral to cell cycle regulation,can induce cellular senescence when abnormally expressed.Furthermore,the findings highlight its potential as an early diagnostic marker.

BACKGROUND:The lactate threshold is a crucial physiological indicator for assessing the aerobic metabolic capacity and training level of endurance athletes,representing the intensity point at which lactate production and clearance reach a dynamic equilibrium within the organism.The traditional lactate threshold training,which is a prolonged and stable-intensity training,aims to enhance the aerobic endurance and lactate clearance efficiency of athletes.In recent years,with the advancement of exercise physiology,double lactate threshold training has emerged as an innovative training modality,drawing extensive attention from both the academic circle and practitioners.Nevertheless,current systematic research on double lactate threshold training remains limited,particularly in aspects such as its physiological mechanisms,optimal implementation plans,and long-term effects.OBJECTIVE:To systematically sort out the development course of double lactate threshold training,deeply analyze its fundamental connotations,objectively assess its application effects,and investigate its physiological action mechanisms,with the expectation of providing scientific basis and guidance for the improvement and optimization of endurance sports training theories and practices.METHODS:With the search terms of"lactate threshold training,double lactate threshold training,lactate training,threshold training,endurance training,Norwegian training method,Norwegian training mode,Norwegian training experience,"a systematic search was conducted in databases,including PubMed,Web of Science,Embase,Medline,Cochrane Library,CNKI,WanFang,and VIP.After screening,8articles met the requirements,involving 8 training cases,and 14 top international athletes,and sports events include 800 m,1 500 m,5 000 m,10 000 m,and cross-country running(9.5 km for men and 4.5 km for women).RESULTS AND CONCLUSION:(1)For the first time,double lactate threshold training was defined as a training strategy aimed at improving aerobic and speed capabilities,involving separate aerobic and anaerobic threshold training sessions within a single training day(aerobic training load intensity requirement of 0.7-2.0 mmol/L,anaerobic training load intensity requirement of 2.0-4.5 mmol/L),with a training frequency of＞2 times per week and a training volume of 120-160 km per week.(2)Double lactate threshold training has positive effects on muscle adaptability and plasticity(dimension and elasticity),increasing aerobic and anaerobic capabilities,and alleviating central neural fatigue and peripheral fatigue.(3)The main mechanisms by which double lactate threshold training yields effects may include hormone secretion,protein synthesis and inhibitory regulation,muscle fiber recruitment and cell swelling,mitochondrial biosynthesis and improvement in the chain of respiratory function,and neurotransmitter regulation.(4)In the practical application of double lactate threshold training,factors such as individualized training plans,load intensity design and monitoring for threshold training days,and applicable sports events should be fully considered.For the systematic improvement of double lactate threshold training,further exploration is still needed in terms of application subjects,training plans,action mechanisms,effect evaluation,and safe application.

BACKGROUND:Autologous bone,allogeneic bone or artificial bone has been used to promote bone defect repair in the clinic,but the rate of non-healing is still high.The key is to ignore the importance of periosteum in the bone healing process.In the early stage of the project,the project team constructed an electrospinning membrane loaded with vascular endothelial growth factor to highly simulate the intramembranous osteogenesis of natural periosteum at the bone defect site,which promoted bone regeneration to a certain extent.However,the injured area often faces the dilemma of severe inflammatory response mediated by macrophages and lack of seed cells,resulting in the risk of inactivation or diffusion of delivered biological factors.Therefore,it is necessary to further optimize and coordinate the immune regulation and angiogenesis functions of biomimetic periosteum to promote bone repair.OBJECTIVE:To investigate the physicochemical properties of stem cell-engineered bionic periosteum and its role in regulating the inflammatory microenvironment to promote bone repair.METHODS:By combining L-polylactic acid-based microsol electrospinning,type Ⅰ collagen self-assembly and gel stem cell transplantation technology,a bionic periosteum(M@C-B)was constructed,in which the core layer loaded with vascular endothelial growth factor and the shell layer delivered bone marrow mesenchymal stem cells to regulate the immune microenvironment of bone defects.The physicochemical properties of the periosteum were characterized by scanning electron microscopy,transmission electron microscopy,and Fourier transform infrared spectroscopy.A co-culture system was established between the bionic periosteum and macrophages,bone marrow mesenchymal stem cells and human umbilical vein endothelial cells to explore immune regulation and in vitro osteogenic and angiogenic abilities.Finally,the osteogenic properties of the stem cell engineered bionic periosteum were further verified in a rat femoral condyle defect model.RESULTS AND CONCLUSION:(1)Transmission electron microscopy results showed that the micro-sol electrospinning(MS)formed a distinct core-shell structure.Scanning electron microscopy indicated that after the assembly of the collagen-l artificial periosteum(M@C)on the surface of the vascular endothelial growth factor-loaded micro-sol,a distinct"spider web-like"fibrous structure was deposited.Infrared spectroscopy further confirmed the successful self-assembly of collagen-l.Release experiments demonstrated that the M@C group mitigated the burst release phenomenon compared to the MS group,maintaining internal vascular endothelial growth factor activity and sustained release.(2)Live/dead cell staining and CCK-8 assay showed that bone marrow mesenchymal stem cells proliferated well and survived on three types of artificial periosteum:MS,purely aligned poly(L-lactic acid)(PLLA)surface self-assembled collagen-l artificial periosteum(PLLA@C),and vascular endothelial growth factor-loaded micro-sol fiber surface self-assembled collagen-l-bone marrow mesenchymal stem cells artificial periosteum(M@C-B).Among them,the M@C-B group had the highest number of live cells and the fastest proliferation rate.(3)Alkaline phosphatase staining,alizarin red staining,and osteopontin immunofluorescence staining showed that the PLLA@C and M@C-B groups significantly promoted osteogenic differentiation of bone marrow mesenchymal stem cells.Angiogenesis experiments demonstrated that the vascular endothelial growth factor-loaded groups(MS and M@C-B)had longer blood vessel lengths and more reticular vascular-like structures with more cross-linked nodes,with the M@C-B group being the most prominent.(4)Immunofluorescence and flow cytometry showed that artificial periosteum in the M@C-B group significantly inhibited the pro-inflammatory macrophage phenotype and promoted the polarization of macrophages towards the anti-inflammatory M2 phenotype.(5)In vivo studies further confirmed that the M@C-B group showed superior bone mineral density,trabecular thickness,relative bone volume,and trabecular spacing compared to other groups.(6)These results indicate that bone marrow mesenchymal stem cell-engineered artificial periosteum,through the rapid regulation of the bone defect immune microenvironment by the collagen-l-bone marrow mesenchymal stem cells outer phase and the sustained release of vascular endothelial growth factor by the micro-sol electrospinning core-shell structure of the inner phase,synergistically promotes bone healing.

BACKGROUND:In previous studies,glass materials were infiltrated into 5Y-PSZ ultra-translucent zirconia by a double sintering method to prepare 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia materials that can maintain high transparency and high flexural strength.OBJECTIVE:To evaluate the in vitro biocompatibility of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia materials.METHODS:(1)Glass materials were infiltrated into 5Y-PSZ ultra-translucent zirconia by double sintering to prepare 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia.5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia(or 5Y-PSZ ultra-translucent zirconia,3Y-TZP transparent zirconia)was placed in DMEM culture medium containing 10％fetal bovine serum for 12,24 and 72 hours,and the surface area ratio of culture medium to sample was 3 mL/cm2,and the 12-,24-and 72-hour material extracts were obtained.(2)After culturing mouse fibroblast L929 for 24 hours,the original culture medium was discarded and divided into 7 groups for culture:the control group was replaced with DMEM culture medium containing 10％fetal bovine serum by volume,and the other 6 groups were replaced with 24-hour extract of 3Y-TZP transparent zirconia,24-hour extract of 5Y-PSZ ultra-translucent zirconia,24-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,72-hour extract of 3Y-TZP transparent zirconia,72-hour extract of 5Y-PSZ ultra-translucent zirconia,and 72-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia.After 1,3,and 5 days of culture,cell growth was observed under a microscope,and the cell proliferation rate was obtained by CCK-8 assay to determine cytotoxicity.(3)Human anticoagulated blood was mixed with 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,5Y-PSZ ultra-translucent zirconia,and 3Y-TZP transparent zirconia,and the hemolysis rate was detected after 0.5 hours.Human anticoagulated blood was mixed with 12-hour extract of 3Y-TZP transparent zirconia,12-hour extract of 5Y-PSZ ultra-translucent zirconia,and 12-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,and the hemolysis rate was detected after 0.5 hours.RESULTS AND CONCLUSION:(1)Under the microscope,it could be seen that the number of cells in each group increased with the extension of culture time,and the cell morphology of each experimental group was basically the same as that of the control group.The cytotoxicity grade of the 24-hour extract of 3Y-TZP transparent zirconia group on the first day of culture was grade 0,and the cytotoxicity grade of the other experimental groups at each time period was grade 1.(2)Neither the material nor the material extract caused obvious hemolytic reaction,and the hemolytic rate was less than 5％.(3)The results showed that 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia had no significant effect on the growth and proliferation of mouse fibroblasts L929,and did not cause hemolytic reaction with human blood,and had good in vitro biocompatibility.

BACKGROUND:3D-printed bone tissue engineering scaffolds have obvious advantages in the research and clinical treatment of bone defect repair.As one of the important raw materials for 3D printed bone scaffolds,poly-L-lactic acid has a great potential for application in performing bone defect repair,but clinical patients with different bone defect causative factors have different requirements for the comprehensive performance of poly-L-lactic acid bone scaffolds.OBJECTIVE:To summarize and review the development of 3D printing technology and poly-L-lactic acid scaffolds and the design strategies chosen for scaffolds for bone repair in the setting of bone diseases such as osteomyelitis,bone tumor,osteonecrosis,and osteoporosis.METHODS:Literature from CNKI,WanFang,PubMed,Science Direct,and Web of Science databases were searched and screened from 1994 to 2024.Search terms were"3D printing,polylactic acid,bone tissue engineering scaffold,osteomyelitis,bone tumor,osteonecrosis,osteoporosis,bone defect"in Chinese and English.The screened 62 articles were systematically summarized and analyzed.RESULTS AND CONCLUSION:(1)Poly-L-lactic acid is considered to be an ideal raw material for artificial bone scaffold design due to its non-toxicity,processability,biocompatibility,and ability to self-degrade in the human environment.The application of 3D printing technology has enabled poly-L-lactic acid bone scaffolds to meet the multilayered and porous structural design requirements of biomimetic artificial bone repair materials,and to optimize the mechanical properties for better bone repair.(2)According to different bone disease microenvironments,timely adjustment of the functional design of poly-L-lactic acid scaffolds is important for the comprehensive osteogenic efficacy of the scaffolds.The article discusses the application of poly-L-lactic acid scaffolds in bone disease environments such as osteomyelitis,bone tumor,osteonecrosis,and osteoporosis,and highlights the importance of rationally grasping the timing of bone disease treatment and bone tissue regeneration for bone defects caused by different bone diseases.(3)Although poly-L-lactic acid scaffolds show potential in bone repair,there are still some problems,such as the need to further optimize the structural design of the scaffolds to fit new bone regeneration,enhance the bioactivity of the scaffolds,and take into account other functions(e.g.,antimicrobial,anti-tumor,and anti-osteoporosis)in order to adapt to the needs of bone tissue repair in different pathological environments.

BACKGROUND:Sarcopenia is an age-related systemic skeletal muscle disease,which is associated with a variety of adverse outcomes such as falls,functional decline,frailty,and death.Postmenopausal women are one of the high-risk groups for sarcopenia.OBJECTIVE:To develop a predictive model for assessing the risk of sarcopenia in Chinese postmenopausal women based on high-quality database.METHODS:Data for this study were derived from 2 370 postmenopausal women from the China Health and Retirement Longitudinal Study(CHARLS),and sarcopenia was assessed using the Asian Working Group on Sarcopenia 2019(AWGS2019)recommended metrics.The study cohort was randomized into a training set(70％)and a validation set(30％).Risk factors for sarcopenia in postmenopausal women were screened using the least absolute shrinkage and selection operator,ten-fold cross-validation,and logistic regression.Nomogram predicting the risk of sarcopenia in postmenopausal women was constructed based on the risk factors,and the model efficacy was evaluated by the receiver operating characteristic curve and area under the curve(AUC),calibration curve,and decision curve analysis.RESULTS AND CONCLUSION:The prevalence of sarcopenia in this study was 23.50％and age,place of residence,sleep quality,cognitive function,depression,and the number of chronic diseases were selected as predictors of sarcopenia in postmenopausal women.The nomogram model showed good discrimination between the training and validation sets,with an AUC value of 0.751(95％confidence interval=0.724-0.778,P＜0.001),a specificity of 72.2％,and a sensitivity of 63.2％in the training set,and an AUC value of 0.763(95％confidence interval=0.721-0.805,P＜0.001),with a specificity of 69.6％and a sensitivity of 70.8％.The calibration curve showed a relatively significant agreement between the nomogram model and the actual observations,and the decision curve analysis demonstrated broad and good clinical utility.To conclude,the nomogram to assess the risk of sarcopenia constructed based on age,place of residence,sleep quality,cognitive function,depression,and number of chronic diseases,provides an effective tool for identifying and eliminating risk factors for sarcopenia in Chinese postmenopausal women,and helps to reduce the incidence of sarcopenia.

BACKGROUND:Studies have shown that lipid metabolism and related diseases can affect the development of osteoporosis.OBJECTIVE:Using bibliometric visualization analysis software to analyze and summarize the frontier content and research hotspots in the field of lipid metabolism affecting osteoporosis.METHODS:Using the Web of Science core collection database as the retrieval platform,relevant literature regarding the effect of lipid metabolism on osteoporosis from 2004 to 2024 was retrieved.VOSviewer and CiteSpace were used for bibliometric and visual analyses.RESULTS AND CONCLUSION:A total of 1 277 articles were included,and the number of articles on the effect of lipid metabolism on osteoporosis at home and abroad was increasing year by year.The number of articles published in China was 417,ranking first,and the United States was 243,ranking second.Shanghai Jiao Tong University ranked first with 30 articles.Professor Rosen Clifford J from Tufts University School of Medicine and Professor Recker Robert R from Clayton University were the most cited authors.The number of documents published in BONE in the Netherlands ranked first,and the JOURNAL OF CLINICAL ENDOCRINOLOGY & METABOLISM in England was the most cited journal.Bone mineral density,bone metabolism,menopause,and obesity were the core keywords,and they were also research hotspots in this field.The above results show that in the past 20 years,research in the field of lipid metabolism affecting osteoporosis has focused on the role of abnormal lipid metabolism in bone mineral density and bone metabolism,thereby regulating osteoporosis and post-menopause osteoporosis.Clarifying the pathway of this mechanism and"bone-lipid balance"is the future research idea and direction.

BACKGROUND:The surgical treatment of severe lumbar fractures is mainly based on posterior short-segment fixation,and different pedicle screw fixation methods have differences in biomechanical properties.OBJECTIVE:To simulate three different screw fixation techniques in the treatment of severe L1 vertebral fractures using three-dimensional finite element technology,and to compare and analyze the biomechanical characteristics of the upper and lower intervertebral discs,fractured vertebrae,and internal fixation devices during the simulated spinal movement.METHODS:A three-dimensional model of the T11-L3 spine was established to simulate severely unstable fracture of the lumbar 1 vertebral body using the designed three pedicle screw fixation methods:Model A with 4 traditional pedicle screws(2 in each T12 and L2),model B with 4 Universal Spine System pedicle screws(2 in each T12 and L2),and Model C were bilateral intermediate fixation with 6 pedicle screws(2 in each of T12,L1,and L2).Restraint and load were applied to simulate the maximum stress and maximum displacement of the internal fixation,the displacement of the L1 vertebral body,and stress on the intervertebral discs superior and inferior to the injured vertebra during the anterior flexion,posterior extension,left-sided bending,right-sided bending and left-right rotation of the lumbar spine.RESULTS AND CONCLUSION:(1)The maximum displacement and motion range of the lumbar 1 vertebra with Model C in flexion and extension,left bending,right bending,left rotation,and right rotation were lowest in the tested motion states;the maximum stress of the screws and connecting rods was the smallest;and the maximum stress of intervertebral discs superior and inferior to the injured vertebra was the smallest.This was followed by the Model B,while the maximum displacement and motion range of the lumbar 1 vertebra and the stress and displacement of the screw connecting rod in the Model A were highest,but it showed the worst biomechanical stability and was more prone to adjacent segment degeneration.(2)These results show that bilateral intermediate fixation with six pedicle screws during the treatment of severe lumbar fractures is more dispersed in internal fixator stress and exhibits the least displacement and motion range of the vertebral pedicle screws and rods compared with four universal spinal system pedicle screws and four traditional pedicle screws.Thus,it can effectively reduce the occurrence of internal fixation failure and the adjacent segment degeneration.