1.Boosting synergism of chemo- and immuno-therapies via switching paclitaxel-induced apoptosis to mevalonate metabolism-triggered ferroptosis by bisphosphonate coordination lipid nanogranules.
Ge SONG ; Minghui LI ; Shumin FAN ; Mengmeng QIN ; Bin SHAO ; Wenbing DAI ; Hua ZHANG ; Xueqing WANG ; Bing HE ; Qiang ZHANG
Acta Pharmaceutica Sinica B 2024;14(2):836-853
Conventional chemotherapy based on cytotoxic drugs is facing tough challenges recently following the advances of monoclonal antibodies and molecularly targeted drugs. It is critical to inspire new potential to remodel the value of this classical therapeutic strategy. Here, we fabricate bisphosphonate coordination lipid nanogranules (BC-LNPs) and load paclitaxel (PTX) to boost the chemo- and immuno-therapeutic synergism of cytotoxic drugs. Alendronate in BC-LNPs@PTX, a bisphosphonate to block mevalonate metabolism, works as both the structure and drug constituent in nanogranules, where alendronate coordinated with calcium ions to form the particle core. The synergy of alendronate enhances the efficacy of paclitaxel, suppresses tumor metastasis, and alters the cytotoxic mechanism. Differing from the paclitaxel-induced apoptosis, the involvement of alendronate inhibits the mevalonate metabolism, changes the mitochondrial morphology, disturbs the redox homeostasis, and causes the accumulation of mitochondrial ROS and lethal lipid peroxides (LPO). These factors finally trigger the ferroptosis of tumor cells, an immunogenic cell death mode, which remodels the suppressive tumor immune microenvironment and synergizes with immunotherapy. Therefore, by switching paclitaxel-induced apoptosis to mevalonate metabolism-triggered ferroptosis, BC-LNPs@PTX provides new insight into the development of cytotoxic drugs and highlights the potential of metabolism regulation in cancer therapy.
2.Study on the effect of different administration regimens of iprrazole enteric-coated tablets on inhibiting gastric acid secretion
Ting-Yuan PANG ; Zhi WANG ; Zi-Shu HU ; Zi-Han SHEN ; Yue-Qi WANG ; Ya-Qian CHEN ; Xue-Bing QIAN ; Jin-Ying LIANG ; Liang-Ying YI ; Jun-Long LI ; Zhi-Hui HAN ; Guo-Ping ZHONG ; Guo-Hua CHENG ; Hai-Tang HU
The Chinese Journal of Clinical Pharmacology 2024;40(1):92-96
Objective To compare the effects of 20 mg qd and 10 mg bidadministration of iprrazole enteric-coated tablets on the control of gastric acid in healthy subjects.Methods A randomized,single-center,parallel controlled trial was designed to include 8 healthy subjects.Randomly divided into 2 groups,20 mg qd administration group:20 mg enteric-coated tablets of iprrazole in the morning;10 mg bid administration group:10 mg enteric-coated tablets of iprrazole in the morning and 10 mg in the evening.The pH values in the stomach of the subjects before and 24 h after administration were monitored by pH meter.The plasma concentration of iprazole after administration was determined by HPLC-MS/MS.The main pharmacokinetic parameters were calculated by Phoenix WinNonlin(V8.0)software.Results The PK parameters of iprrazole enteric-coated tablets and reference preparations in fasting group were as follows:The Cmax of 20 mg qd group and 10 mg bid group were(595.75±131.15)and(283.50±96.98)ng·mL-1;AUC0-t were(5 531.94±784.35)and(4 686.67±898.23)h·ng·mL-1;AUC0-∞ were(6 003.19±538.59)and(7 361.48±1 816.77)h·ng·mL-1,respectively.The mean time percentage of gastric pH>3 after 20 mg qd and 10 mg bid were 82.64%and 61.92%,and the median gastric pH within 24 h were 6.25±1.49 and 3.53±2.05,respectively.The mean gastric pH values within 24 h were 5.71±1.36 and 4.23±1.45,respectively.The correlation analysis of pharmacokinetic/pharmacodynamics showed that there was no significant correlation between the peak concentration of drug in plasma and the inhibitory effect of acid.Conclusion Compared with the 20 mg qd group and the 10 mg bid group,the acid inhibition effect is better,the administration times are less,and the safety of the two administration regimes is good.
3.Consideration on the non-clinical evaluation of therapeutic mRNA vaccines for tumors
Shuang WU ; Yin WANG ; Hua-Jing YIN ; Zheng LI ; Mao-Shan YIN ; Bing YU
The Chinese Journal of Clinical Pharmacology 2024;40(20):3061-3064
Therapeutic mRNA vaccine for tumors attracted much attention as a new type of tumor treatment,and most products are in the preclinical and clinical research stage,and there has not post-market drug.However,the non-clinical evaluation of therapeutic mRNA vaccines for tumors is more complicated,due to their target features,mechanisms,delivery patterns,and the cross-species differences of immune system.The choice of animal model is not only content of the clinical effectiveness,and it was a key factor of toxicity assessment.In this work,the challenges for non-clinical evaluation of therapeutic mRNA vaccines for tumors are discussed,and the compliant requirements are reviewed,and the general considerations are suggested.
4.Experts consensus on standard items of the cohort construction and quality control of temporomandibular joint diseases (2024)
Min HU ; Chi YANG ; Huawei LIU ; Haixia LU ; Chen YAO ; Qiufei XIE ; Yongjin CHEN ; Kaiyuan FU ; Bing FANG ; Songsong ZHU ; Qing ZHOU ; Zhiye CHEN ; Yaomin ZHU ; Qingbin ZHANG ; Ying YAN ; Xing LONG ; Zhiyong LI ; Yehua GAN ; Shibin YU ; Yuxing BAI ; Yi ZHANG ; Yanyi WANG ; Jie LEI ; Yong CHENG ; Changkui LIU ; Ye CAO ; Dongmei HE ; Ning WEN ; Shanyong ZHANG ; Minjie CHEN ; Guoliang JIAO ; Xinhua LIU ; Hua JIANG ; Yang HE ; Pei SHEN ; Haitao HUANG ; Yongfeng LI ; Jisi ZHENG ; Jing GUO ; Lisheng ZHAO ; Laiqing XU
Chinese Journal of Stomatology 2024;59(10):977-987
Temporomandibular joint (TMJ) diseases are common clinical conditions. The number of patients with TMJ diseases is large, and the etiology, epidemiology, disease spectrum, and treatment of the disease remain controversial and unknown. To understand and master the current situation of the occurrence, development and prevention of TMJ diseases, as well as to identify the patterns in etiology, incidence, drug sensitivity, and prognosis is crucial for alleviating patients′suffering.This will facilitate in-depth medical research, effective disease prevention measures, and the formulation of corresponding health policies. Cohort construction and research has an irreplaceable role in precise disease prevention and significant improvement in diagnosis and treatment levels. Large-scale cohort studies are needed to explore the relationship between potential risk factors and outcomes of TMJ diseases, and to observe disease prognoses through long-term follw-ups. The consensus aims to establish a standard conceptual frame work for a cohort study on patients with TMJ disease while providing ideas for cohort data standards to this condition. TMJ disease cohort data consists of both common data standards applicable to all specific disease cohorts as well as disease-specific data standards. Common data were available for each specific disease cohort. By integrating different cohort research resources, standard problems or study variables can be unified. Long-term follow-up can be performed using consistent definitions and criteria across different projects for better core data collection. It is hoped that this consensus will be facilitate the development cohort studies of TMJ diseases.
5.Expert consensus on surgical treatment of oropharyngeal cancer
China Anti-Cancer Association Head and Neck Oncology Committee ; China Anti-Cancer Association Holistic Integrative Oral Cancer on Preventing and Screen-ing Committee ; Min RUAN ; Nannan HAN ; Changming AN ; Chao CHEN ; Chuanjun CHEN ; Minjun DONG ; Wei HAN ; Jinsong HOU ; Jun HOU ; Zhiquan HUANG ; Chao LI ; Siyi LI ; Bing LIU ; Fayu LIU ; Xiaozhi LV ; Zheng-Hua LV ; Guoxin REN ; Xiaofeng SHAN ; Zhengjun SHANG ; Shuyang SUN ; Tong JI ; Chuanzheng SUN ; Guowen SUN ; Hao TIAN ; Yuanyin WANG ; Yueping WANG ; Shuxin WEN ; Wei WU ; Jinhai YE ; Di YU ; Chunye ZHANG ; Kai ZHANG ; Ming ZHANG ; Sheng ZHANG ; Jiawei ZHENG ; Xuan ZHOU ; Yu ZHOU ; Guopei ZHU ; Ling ZHU ; Susheng MIAO ; Yue HE ; Jugao FANG ; Chenping ZHANG ; Zhiyuan ZHANG
Journal of Prevention and Treatment for Stomatological Diseases 2024;32(11):821-833
With the increasing proportion of human papilloma virus(HPV)infection in the pathogenic factors of oro-pharyngeal cancer,a series of changes have occurred in the surgical treatment.While the treatment mode has been im-proved,there are still many problems,including the inconsistency between diagnosis and treatment modes,the lack of popularization of reconstruction technology,the imperfect post-treatment rehabilitation system,and the lack of effective preventive measures.Especially in terms of treatment mode for early oropharyngeal cancer,there is no unified conclu-sion whether it is surgery alone or radiotherapy alone,and whether robotic minimally invasive surgery has better func-tional protection than radiotherapy.For advanced oropharyngeal cancer,there is greater controversy over the treatment mode.It is still unclear whether to adopt a non-surgical treatment mode of synchronous chemoradiotherapy or induction chemotherapy combined with synchronous chemoradiotherapy,or a treatment mode of surgery combined with postopera-tive chemoradiotherapy.In order to standardize the surgical treatment of oropharyngeal cancer in China and clarify the indications for surgical treatment of oropharyngeal cancer,this expert consensus,based on the characteristics and treat-ment status of oropharyngeal cancer in China and combined with the international latest theories and practices,forms consensus opinions in multiple aspects of preoperative evaluation,surgical indication determination,primary tumor re-section,neck lymph node dissection,postoperative defect repair,postoperative complication management prognosis and follow-up of oropharyngeal cancer patients.The key points include:① Before the treatment of oropharyngeal cancer,the expression of P16 protein should be detected to clarify HPV status;② Perform enhanced magnetic resonance imaging of the maxillofacial region before surgery to evaluate the invasion of oropharyngeal cancer and guide precise surgical resec-tion of oropharyngeal cancer.Evaluating mouth opening and airway status is crucial for surgical approach decisions and postoperative risk prediction;③ For oropharyngeal cancer patients who have to undergo major surgery and cannot eat for one to two months,it is recommended to undergo percutaneous endoscopic gastrostomy before surgery to effectively improve their nutritional intake during treatment;④ Early-stage oropharyngeal cancer patients may opt for either sur-gery alone or radiation therapy alone.For intermediate and advanced stages,HPV-related oropharyngeal cancer general-ly prioritizes radiation therapy,with concurrent chemotherapy considered based on tumor staging.Surgical treatment is recommended as the first choice for HPV unrelated oropharyngeal squamous cell carcinoma(including primary and re-current)and recurrent HPV related oropharyngeal squamous cell carcinoma after radiotherapy and chemotherapy;⑤ For primary exogenous T1-2 oropharyngeal cancer,direct surgery through the oral approach or da Vinci robotic sur-gery is preferred.For T3-4 patients with advanced oropharyngeal cancer,it is recommended to use temporary mandibu-lectomy approach and lateral pharyngotomy approach for surgery as appropriate;⑥ For cT1-2N0 oropharyngeal cancer patients with tumor invasion depth>3 mm and cT3-4N0 HPV unrelated oropharyngeal cancer patients,selective neck dissection of levels ⅠB to Ⅳ is recommended.For cN+HPV unrelated oropharyngeal cancer patients,therapeutic neck dissection in regions Ⅰ-Ⅴ is advised;⑦ If PET-CT scan at 12 or more weeks after completion of radiation shows intense FDG uptake in any node,or imaging suggests continuous enlargement of lymph nodes,the patient should undergo neck dissection;⑧ For patients with suspected extracapsular invasion preoperatively,lymph node dissection should include removal of surrounding muscle and adipose connective tissue;⑨ The reconstruction of oropharyngeal cancer defects should follow the principle of reconstruction steps,with priority given to adjacent flaps,followed by distal pedicled flaps,and finally free flaps.The anterolateral thigh flap with abundant tissue can be used as the preferred flap for large-scale postoperative defects.
6.YTE-17 inhibits colonic carcinogenesis by resetting antitumor immune response via Wnt5a/JNK mediated metabolic signaling
Sui HUA ; Deng WANLI ; Chai QIONG ; Han BING ; Zhang YULI ; Wei ZHENZHEN ; Li ZAN ; Wang TING ; Feng JILING ; Yuan MAN ; Tang QINGFENG ; Xu HONGXI
Journal of Pharmaceutical Analysis 2024;14(4):525-541
The density and composition of lymphocytes infiltrating colon tumors serve as predictive factors for the clinical outcome of colon cancer.Our previous studies highlighted the potent anti-cancer properties of the principal compounds found in Garcinia yunnanensis(YTE-17),attributing these effects to the regu-lation of multiple signaling pathways.However,knowledge regarding the mechanism and effect of YTE-17 in the prevention of colorectal cancer is limited.In this study,we conducted isobaric tags for relative and absolute quantification(iTRAQ)analysis on intestinal epithelial cells(IECs)exposed YTE-17,both in vitro and in vivo,revealing a significant inhibition of the Wnt family member 5a(Wnt5a)/c-Jun N-terminal kinase(JNK)signaling pathway.Subsequently,we elucidated the influence and mechanism of YTE-17 on the tumor microenvironment(TME),specifically focusing on macrophage-mediated T helper 17(Th17)cell induction in a colitis-associated cancer(CAC)model with Wnt5a deletion.Additionally,we performed the single-cell RNA sequencing(scRNA-seq)on the colonic tissue from the Wnt5a-deleted CAC model to characterize the composition,lineage,and functional status of immune mesenchymal cells during different stages of colorectal cancer(CRC)progression.Remarkably,our findings demon-strate a significant reduction in M2 macrophage polarization and Th17 cell phenotype upon treatment with YTE-17,leading to the restoration of regulatory T(Treg)/Th17 cell balance in azoxymethane(AOM)/dextran sodium sulfate(DSS)model.Furthermore,we also confirmed that YTE-17 effectively inhibited the glycolysis of Th17 cells in both direct and indirect co-culture systems with M2 macrophages.Notably,our study shed light on potential mechanisms linking the non-canonical Wnt5a/JNK signaling pathway and well-established canonical β-catenin oncogenic pathway in vivo.Specifically,we proposed that Wnt5a/JNK signaling activity in IECs promotes the development of cancer stem cells with β-catenin activity within the TME,involving macrophages and T cells.In summary,our study undergoes the po-tential of YTE-17 as a preventive strategy against CRC development by addressing the imbalance with the immune microenvironment,thereby mitigating the risk of malignancies.
7.Environmental hygiene and healthcare-associated infection:a time-series study based on generalized additive model
Kai LIN ; Kun CHEN ; Jian-Bing WANG ; Fang-Hua FAN ; Hui LIANG ; Fang CHEN ; Kai-Ling JIN ; Wen-Jie CHU ; Wei-Guo CHEN ; Huan SHAN
Chinese Journal of Infection Control 2024;23(7):798-805
Objective To quantitatively analyze the impact of environmental hygiene on the occurrence of health-care-associated infections(HAI).Methods Monitoring data of HAI and environmental hygiene from a tertiary first-class hospital from January 2018 to December 2022 were collected,and the impact of environmental bacterial colony forming unit(CFU)on the occurrence of HAI was analyzed by a time-series generalized additive model.Results The single-contamination model showed a significant positive correlation between HAI and staff's hand bacterial CFU(β1=0.009,P=0.012).For an increase of 1 interquartile range(IQR)in the monthly mean CFU per dish(MCFU/Dish)of staffs'hand,the incidence of HAI increased by 13.28%(95%CI:2.82%-24.81%).Subgroup and lag effect analysis showed that when the monthly MCFU/Dish(after hand disinfection)of staffs'hand in-creased by one IQR,the excess risk(ER)of HAI for the month(lag0)was 16.26%(95%CI:15.45%-17.09%).In the multi-contamination model,the correlation between surface contamination and HAI was also statistically sig-nificant.Conclusion There is a significant correlation between hospital environmental hygiene and the occurrence of HAI.
8.Homology analysis of Acinetobacter baumannii in intensive care unit be-fore and after COVID-19 pandemic
Xiao WANG ; Yan-Ru LIANG ; Yue ZHANG ; Xiang-Hua LU ; Jun FENG ; Yuan-Ping WANG ; Bing ZHAO
Chinese Journal of Infection Control 2024;23(10):1213-1219
Objective To investigate the distribution of pathogens and change of homology of Acinetobacter bau-mannii(AB)in intensive care units(ICUs)of partial medical institutions in Shanghai before and after the pandemic of coronavirus disease 2019(COVID-19).Methods Pathogens were isolated and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS),the whole genome of AB was sequenced using Illumina Miseq sequencing platform,and its genetic relationship was explored based on multilocus sequence typing(MLST)and core genome multilocus sequence typing(cgMLST).Results The total detection rate of patho-gens in ICU environment after the pandemic was lower than before the pandemic([6.10%,101/1 656]vs[10.77%,181/1 680];P<0.05).Before and after the pandemic,the proportion of AB detected on the surface of bedding in the ICU environment remained at the highest level.After the pandemic,the ST types showed a diverse distribution.MLST_Pasteur results showed that 162 strains of AB were divided into 20 ST types,with ST2(80.25%,n=130)being the main type.MLST_Oxford results showed that there were 19 ST types among 162 strains,with ST208(37.04%,n=60)being the main type.The clustering analysis based on cgMLST showed that ST208_Oxford had closer genetic relationship with ST540_Oxford and ST369_Oxford after the pandemic.ST164_Pasteur clone changed from ST234_Oxford before the pandemic to ST1418_Oxford after the pandemic,and 2 new types of ST_Pasteurr and 11 new types of ST_Oxford were discovered.Conclusion The detection rate of pathogens from ICU environment after the pandemic is lower than before the pandemic,and the distribution of ST types is slightly different at the same detection sites before and after the pandemic.ST2_Pasteur/ST208_Oxford is still the dominant epidemic clone before and after the pandemic,but some alleles have changed.cgMLST is more accurate than MLST_Oxford and MLST_Pasteur in homology analysis,evolution,spread,and outbreak analysis.
9.Disease characteristics and costs of pediatric Mycoplasma Pneumoniae pneumonia hospitalization:a retrospective study at municipal hospitals from 2019 to 2023 in Shanghai
Ying-Wen WANG ; Feng WANG ; Li-Bo WANG ; Ai-Zhen LU ; Yi WANG ; Yong-Hao GUI ; Quan LU ; Yong YIN ; Jian-Hua ZHANG ; Ying-Zi YE ; Hong XU ; Bing SHEN ; Dan-Ping GU ; Xiao-Yan DONG ; Jia-Yu WANG ; Wen HE ; Xiao-Bo ZHANG
Fudan University Journal of Medical Sciences 2024;51(4):515-521
Objective To investigate disease characteristics and hospitalization costs of children with Mycoplasma Pneumoniae pneumonia(MPP)admitted to Shanghai municipal medical hospitals from 2019 to 2023.Methods Depending on the Shanghai Municipal Hospital Pediatric Alliance,we retrospectively investigated community acquired MPP pediatric patients hospitalized in 22 municipal hospitals with pediatric qualifications(including 4 children's hospitals)in Shanghai from Jan 2019 to Dec 2023.We collected the patients'diagnosis codes,gender,age,length of hospital stay,hospitalization costs,and whether they progressed to severe Mycoplasma pneumoniae pneumonia(SMPP).Results From 2019 to 2023,a total of 29 045 hospitalized children with MPP were treated,with 6 035 cases(20.8%)identified as SMPP in the 22 hospitals.Trend analysis revealed a rising trend with years in the proportion of SMPP patients(χ2trend=365.498,P<0.001).Among the 4 children's hospitals,there were 18 710 cases with MPP,including 4 078 cases(21.8%)of SMPP.The proportion of SMPP patients also showed an increasing trend with years(χ2trend=14.548,P<0.001),and the proportion in 2023(23.0%)was higher than that in previous years with statistical significance.There were statistical differences in the seasonal distribution of MPP cases between different years,with higher proportions in summer and autumn overall.The age distribution of hospitalized MPP children varied among different years,with school-age children accounting for the majority(56.8%)in 2023.There was no difference in the distribution of severe cases between different genders,but there were differences in the proportion of severe cases among different age groups in different years,with a gradual increase in severe cases among children aged 1 to 3 years(χ2trend=191.567,P<0.001).The average length of hospital stay for MPP during the epidemic was higher than that during non-epidemic periods,and there were statistically significant differences in the average length of hospital stay between different years(P<0.001).The individual hospitalization costs during the epidemic were higher than in other years,and there were statistically significant differences in individual hospitalization costs between different years(P<0.001).The total hospitalization costs were still higher in 2019 and 2023.The individual hospitalization costs for SMPP were higher than for non-SMPP cases.Conclusion MPP outbreaks occurred in Shanghai in 2019 and 2023,with the higher proportions in summer and autumn overall.Compared to previous years,the number of hospitalized MPP children in Shanghai was higher in 2023,with a higher proportion of SMPP cases,especially among children under 3 years old.The individual per capita hospitalization expenses for SMPP cases were higher than for non-SMPP cases.
10.Computer-aided design of an improved lamina hook and finite element analysis of its use in fixation of lumbar spondylolysis
Hongliang GAO ; Hua LIU ; Tao ZHANG ; Chengwei YANG ; Yizhe WANG ; Zirong HUANG ; Wenhua ZHANG ; Long CHEN ; Bing KANG ; Yuxuan MA ; Songkai LI
Chinese Journal of Trauma 2024;40(7):593-604
Objective:To design an improved lamina hook system and compare its biomechanical properties with traditional lamina hook system in fixation of lumbar spondylolysis.Methods:The thin layer CT data of the lumbosacral vertebrae of 20 healthy young male servicemen who underwent physical examination in the outpatient department of the 940th Hospital of Joint Logistics Support Force of PLA from January 2021 to August 2022 were collected. The age of the subjects was 20-30 years [(25.0±3.0)years]. A 3-dimensional model of the L 5 vertebral body was constructed using the 3-dimensional modeling software. The new improved lamina hook was designed according to the measurements including the thickness of the middle area, the longest longitudinal diameter, the curvature radius of the lower edge, the angle between the upper and lower tail ends, the thickness of the lower edge, and the longest diameter of the lower edge of the bilateral L 5 vertebral plates. One serviceman was selected from the aforementioned group to construct a linear finite element model of segments L 4-S using the 3-dimensional virtual software (normal model, model A), based on which, the L 5 bilateral spondylolysis model (model B), improved lamina hook model (model C) and traditional lamina hook models (model D) were designed. By constraining both sides of the sacrum and applying a longitudinal load of 400 N on the L 4 vertebral body, the upper 1/3 gravity of the body was simulated, and with a bending moment of 10 N·m along the X, Y, and Z directions, motions of forward flexion, backward extension, lateral bending, rotation, etc were simulated. The range of motion of segment L 4/5 and L 5/S 1 of model A was evaluated and compared with the findings of the previous researches to verify its effectiveness. The overall range of motion of models A, B, C, and D, the range of motion of segment L 4/5 and L 5/S 1, the maximum overall displacement, the maximum displacement and stress of the isthmus, the stress distribution and maximum stress of internal fixation of models C and D, and the stress distribution and maximum stress of the vertebral body of models C and D were compared. Results:(1) During forward flexion, backward extension, lateral bending and rotation, the range of motion of model A was 5.01°, 4.03°, 3.91° and 1.42° in segment L 4/5, and was 4.62°, 2.51°, 2.40° and 1.23° in segment L 5/S 1. (2) The overall range of motion, range of motion of segment L 4/5 and L 5/S 1 and maximum overall displacement of models A, C, and D were similar in axial compression, forward flexion, backward extension, left bending, and left rotation, while those of model B were significantly increased. (3) There was no significant difference in the maximum displacement of the isthmus of models A, C, and D under different motion modes, while the maximum displacement of model B in the isthmus was significantly larger than that of models A, C, and D, especially during rotation, increased by 295%, 277%, and 276% respectively. The maximum stress of the isthmus of model C was 0.938 MPa, 1.698 MPa, 0.410 MPa, 2.775 MPa, and 1.554 MPa respectively. The maximum stress in the isthmus of model D was 0.590 MPa, 1.297 MPa, 0.520 MPa, 3.088 MPa, and 2.072 MPa respectively. The maximum stress of the isthmus of models C and D was similar during axial compression and forward flexion, while the stress of the isthmus of model C was smaller than that of model D during backward extension, lateral bending, and rotation, decreased by 21.1%, 10.2%, and 25.0% respectively compared with model D. (4) The maximum stress of internal fixation in models C and D during forward flexion, backward extension, left bending, and left rotation was 135.220 MPa, 130.180 MPa, 200.940 MPa and 306.340 MPa respectively, and was 131.840 MPa, 112.280 MPa, 349.980 MPa and 370.140 MPa respectively. The maximum stress of internal fixation in the two models of internal fixation during forward flexion and backward extension was similar, while it was decreased by 42.6% and 17.2% in model C during left bending and left rotation, compared with model D. (5) The maximum stress of the vertebral body during forward flexion, backward extension, left bending, and left rotation was 79.787 MPa, 36.857 MPa, 37.943 MPa and 96.965 MPa respectively in model C, but was 80.104 MPa, 64.236 MPa, 196.010 MPa and 193.020 MPa respectively in model D. The maximum stress of models C and D was all distributed in the contact area with the internal fixation, and especially during backward extension, left bending, and left rotation, when it was reduced by 42.6%, 80.6%, and 49.8% of model C respectively, compared with that of model D. Conclusions:The improved laminar hook is more consistent with the Chinese anatomized structure of the lamina. Compared with the traditional lamina hook system, the improved lamina hook system can effectively reduce the displacement in all directions and range of motion of lumbar spondylolysis, therefor can significantly reduce the stress of internal fixation and vertebral body and has better biomechanical performance.


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