1.In situ Analytical Techniques for Membrane Protein Interactions
Zi-Yuan KANG ; Tong YU ; Chao LI ; Xue-Hua ZHANG ; Jun-Hui GUO ; Qi-Chang LI ; Jing-Xing GUO ; Hao XIE
Progress in Biochemistry and Biophysics 2025;52(5):1206-1218
Membrane proteins are integral components of cellular membranes, accounting for approximately 30% of the mammalian proteome and serving as targets for 60% of FDA-approved drugs. They are critical to both physiological functions and disease mechanisms. Their functional protein-protein interactions form the basis for many physiological processes, such as signal transduction, material transport, and cell communication. Membrane protein interactions are characterized by membrane environment dependence, spatial asymmetry, weak interaction strength, high dynamics, and a variety of interaction sites. Therefore, in situ analysis is essential for revealing the structural basis and kinetics of these proteins. This paper introduces currently available in situ analytical techniques for studying membrane protein interactions and evaluates the characteristics of each. These techniques are divided into two categories: label-based techniques (e.g., co-immunoprecipitation, proximity ligation assay, bimolecular fluorescence complementation, resonance energy transfer, and proximity labeling) and label-free techniques (e.g., cryo-electron tomography, in situ cross-linking mass spectrometry, Raman spectroscopy, electron paramagnetic resonance, nuclear magnetic resonance, and structure prediction tools). Each technique is critically assessed in terms of its historical development, strengths, and limitations. Based on the authors’ relevant research, the paper further discusses the key issues and trends in the application of these techniques, providing valuable references for the field of membrane protein research. Label-based techniques rely on molecular tags or antibodies to detect proximity or interactions, offering high specificity and adaptability for dynamic studies. For instance, proximity ligation assay combines the specificity of antibodies with the sensitivity of PCR amplification, while proximity labeling enables spatial mapping of interactomes. Conversely, label-free techniques, such as cryo-electron tomography, provide near-native structural insights, and Raman spectroscopy directly probes molecular interactions without perturbing the membrane environment. Despite advancements, these methods face several universal challenges: (1) indirect detection, relying on proximity or tagged proxies rather than direct interaction measurement; (2) limited capacity for continuous dynamic monitoring in live cells; and (3) potential artificial influences introduced by labeling or sample preparation, which may alter native conformations. Emerging trends emphasize the multimodal integration of complementary techniques to overcome individual limitations. For example, combining in situ cross-linking mass spectrometry with proximity labeling enhances both spatial resolution and interaction coverage, enabling high-throughput subcellular interactome mapping. Similarly, coupling fluorescence resonance energy transfer with nuclear magnetic resonance and artificial intelligence (AI) simulations integrates dynamic structural data, atomic-level details, and predictive modeling for holistic insights. Advances in AI, exemplified by AlphaFold’s ability to predict interaction interfaces, further augment experimental data, accelerating structure-function analyses. Future developments in cryo-electron microscopy, super-resolution imaging, and machine learning are poised to refine spatiotemporal resolution and scalability. In conclusion, in situ analysis of membrane protein interactions remains indispensable for deciphering their roles in health and disease. While current technologies have significantly advanced our understanding, persistent gaps highlight the need for innovative, integrative approaches. By synergizing experimental and computational tools, researchers can achieve multiscale, real-time, and perturbation-free analyses, ultimately unraveling the dynamic complexity of membrane protein networks and driving therapeutic discovery.
2.Triglyceride-glucose index and homocysteine in association with the risk of stroke in middle-aged and elderly diabetic populations
Xiaolin LIU ; Jin ZHANG ; Zhitao LI ; Xiaonan WANG ; Juzhong KE ; Kang WU ; Hua QIU ; Qingping LIU ; Jiahui SONG ; Jiaojiao GAO ; Yang LIU ; Qian XU ; Yi ZHOU ; Xiaonan RUAN
Shanghai Journal of Preventive Medicine 2025;37(6):515-520
ObjectiveTo investigate the triglyceride-glucose (TyG) index and the level of serum homocysteine (Hcy) in association with the incidence of stroke in type 2 diabetes mellitus (T2DM) patients. MethodsBased on the chronic disease risk factor surveillance cohort in Pudong New Area, Shanghai, excluding those with stroke in baseline survey, T2DM patients who joined the cohort from January 2016 to October 2020 were selected as the research subjects. During the follow-up period, a total of 318 new-onset ischemic stroke patients were selected as the case group, and a total of 318 individuals matched by gender without stroke were selected as the control group. The Cox proportional hazards regression model was used to adjust for confounding factors and explore the serum TyG index and the Hcy biochemical indicator in association with the risk of stroke. ResultsThe Cox proportional hazards regression results showed that after adjusting for confounding factors, the risk of stroke in T2DM patients with 10 μmol·L⁻¹
3.Ameliorative effects of Lycii Fructus-Chrysanthemi Flos at different ratios on retinal damage in mice.
Bing LI ; Sheng GUO ; Yue ZHU ; Xue-Sen WANG ; Dan-Dan WEI ; Hong-Jie KANG ; Wen-Hua ZHANG ; Jin-Ao DUAN
China Journal of Chinese Materia Medica 2025;50(3):732-740
This study aimed to compare the ameliorative effects of Lycii Fructus and Chrysanthemi Flos at different ratios on retinal damage in mice and to elucidate the underlying mechanisms. A retinal injury model was established by intraperitoneal injection of sodium iodate(NaIO_3) solution. The mice were divided into the following groups: blank group, model group, positive drug(AREDS 2) group, low-and high-dose groups of Lycii Fructus and Chrysanthemi Flos at 1∶1, low-and high-dose groups at 3∶1, and low-and high-dose groups at 1∶3. Administration was carried out 15 days after modeling. The visual acuity of the mice was assessed using the black-and-white box test. The fundus was observed using an optical coherence tomography device, and retinal thickness was measured. HE staining was used to observe the morphology and pathological changes of the retina. The levels of oxidative factors in serum and ocular tissues were measured using assay kits. The levels of inflammatory factors in serum and ocular tissues were detected by enzyme-linked immunosorbent assay(ELISA), and the expression of Nrf2, HO-1, and NF-κB proteins in ocular tissues was analyzed by Western blot. The results showed that after administration of Lycii Fructus and Chrysanthemi Flos at different ratios, the model group showed improved retinal thinning and disordered arrangement of retinal layers, elevated content of SOD and GSH in the serum and ocular tissues, and reduced levels of MDA, TNF-α, IL-1β, and IL-6. Lycii Fructus and Chrysanthemi Flos at 1∶1 and 1∶3 showed better improvement effects. The combination significantly upregulated the expression levels of Nrf2 and HO-1 and downregulated the expression of NF-κB p65. These results indicate that Lycii Fructus and Chrysanthemi Flos at different ratios can improve retinal damage, reduce oxidative stress, and alleviate inflammation in both the body and ocular tissues of mice. The mechanism may be related to the regulation of the Nrf2/HO-1 and NF-κB signaling pathways in ocular tissues. These findings provide a theoretical basis for the clinical application of Lycii Fructus and Chrysanthemi Flos in the treatment of dry age-related macular degeneration.
Animals
;
Mice
;
Retina/injuries*
;
Male
;
Lycium/chemistry*
;
Drugs, Chinese Herbal/administration & dosage*
;
Chrysanthemum/chemistry*
;
NF-kappa B/genetics*
;
Humans
;
Retinal Diseases/metabolism*
;
NF-E2-Related Factor 2/metabolism*
;
Oxidative Stress/drug effects*
;
Flowers/chemistry*
;
Heme Oxygenase-1/genetics*
4.Clinical and genetic characteristics of congenital adrenal hyperplasia: a retrospective analysis.
Cai-Jun WANG ; Ya-Wei ZHANG ; Da-Peng LIU ; Juan JIN ; Zhao-Hui LI ; Jing GUO ; Yao-Dong ZHANG ; Hai-Hua YANG ; Wen-Qing KANG
Chinese Journal of Contemporary Pediatrics 2025;27(11):1367-1372
OBJECTIVES:
To study the clinical and genetic characteristics of children with congenital adrenal hyperplasia (CAH).
METHODS:
Clinical data, laboratory findings, and genetic test results of 63 children diagnosed with CAH at Henan Children's Hospital from January 2017 to December 2024 were retrospectively reviewed.
RESULTS:
Of the 63 patients, the mean age at the first visit was (21 ± 14) days; 29 (46%) were of male sex and 34 (54%) were of female sex. The predominant clinical manifestations were poor weight gain or weight loss (92%, 58/63), poor feeding (84%, 53/63), skin hyperpigmentation (83%, 52/63), and female external genital anomalies (100%, 34/34). Laboratory abnormalities included hyponatremia (87%, 55/63), hyperkalemia (68%, 43/63), metabolic acidosis (68%, 43/63), and markedly elevated 17-hydroxyprogesterone (92%, 58/63), testosterone (89%, 56/63), and adrenocorticotropic hormone (81%, 51/63). Among 49 patients who underwent genetic testing, CYP21A2 variants were identified in 90% (44/49), with c.293-13A/C>G (33%, 30/91) and large deletions/gene conversions (29%, 26/91) being the most frequent; STAR (8%, 4/49) and HSD3B2 (2%, 1/49) variants were also detected. Following hormone replacement therapy, electrolyte disturbances were corrected in 57 cases, with significant reductions in 17-hydroxyprogesterone, adrenocorticotropic hormone, and testosterone levels (P<0.001).
CONCLUSIONS
CAH presenting in neonates or young infants is characterized by electrolyte imbalance, external genital anomalies, and abnormal hormone levels. Genetic testing enables definitive subtype classification; in CYP21A2-related CAH, c.293-13A/C>G is a hotspot variant. These findings underscore the clinical value of genetic testing for early diagnosis and genetic counseling in CAH. Citation:Chinese Journal of Contemporary Pediatrics, 2025, 27(11): 1367-1372.
Humans
;
Adrenal Hyperplasia, Congenital/diagnosis*
;
Male
;
Female
;
Retrospective Studies
;
Infant
;
Infant, Newborn
5.Symptoms and treatment of benign prostatic hyperplasia patients with upper urinary tract calculi after ureteral stent implantation.
Wei LIU ; Hui ZHANG ; Shuang-Ning LIU ; Shao-Hua BIAN ; Qi-Yuan KANG ; Ying-Yi LI ; Qiao DU ; Wen-Bing YUAN ; Jiang ZHU
National Journal of Andrology 2025;31(7):608-611
Objective: To analyze the symptoms, diagnosis and treatment of upper urinary tract calculi patients combined with mild and moderate benign prostatic hyperplasia (BPH) after ureteral stent implantation. Methods: One hundred and six BPH patients who were hospitalized for upper urinary tract calculi and had ureteral stents retained from January 2019 to December 2022 were selected and divided into 2 weeks group and 4 weeks group according to the time of removal of ureteral stents after surgery. Their general clinical data were analyzed and compared. International Prostatic Symptom Scale (IPSS), postoperative ureteral Stent Symptom Questionnaire (USSQ), and incidence of adverse events after ureteral stent removal were recorded before and after removal. Results: The scores of IPSS were significantly increased in all patients, and symptoms in urinary tract had improved significantly after discharge (P<0.05). Compared with the 2 weeks group, the USSQ score of the 4 weeks group was significantly increased (P<0.05). And no significant adverse event was observed in the 2 weeks group after the removal of ureteral sten. Conclusion: IPSS score and USSQ score increased significantly during stent implantation in BPH patients with lithiasis. And complications increased significantly over time. Following thorough clinical assessment, early ureteral stent removal demonstrates both safety and efficacy, representing an optimal therapeutic approach in selected cases.
Humans
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Male
;
Prostatic Hyperplasia/surgery*
;
Stents
;
Ureter/surgery*
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Aged
;
Middle Aged
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Urinary Calculi/surgery*
;
Ureteral Calculi/surgery*
6.Inhibitory Effects of Nardostachys Jatamansi DC. Volatile Oil on Psychological Factors SP/CORT-Induced Hyperpigmentation.
Man YANG ; Kang CHENG ; Jie GU ; Hua-Li WU ; Yi-Ming LI
Chinese journal of integrative medicine 2025;31(12):1097-1104
OBJECTIVE:
To explore the inhibitory effects of Nardostachys Jatamansi DC. volatile oil (NJVO) on psychological factors substance P (SP)/cortisol (CORT)-induced hyperpigmentation.
METHODS:
The model of psychologically-induced hyperpigmentation of B16F10 cells was created using SP (10 nmol/L) + CORT (10 µmol/L) for 72 h. The levels of melanin content, tyrosinase (TYR) activity using NaOH lysis and L-dihydroxyphenylalanine (L-DOPA) oxidation methods were assessed, respectively. The effect of NJVO on SP/CORT-induced normal human skin tissue pigmentation was detected by Masson staining. Protein expressions of tyrosinase-related protein 1 (TRP-1), tyrosinase-relative protein 2 (DCT), and microphthalmia-associated transcription factor were determined using Western blot. The melanosome number, maturation, and melanosomal structure changes were detected through transmission electron microscopy and immunofluorescence experiments. In vivo, zebrafish pigment content was evaluated in SP/CORT-induced zebrafish hyperpigmentation model.
RESULTS:
NJVO significantly reduced the melanin content (P<0.01) and inhibited tyrosinase activity (P<0.01), the pigmentation of the normal skin tissue in the NJVO group was significantly lower than that in the SP/CORT group (P<0.05). And NJVO considerably downregulated expressions of melanogenesis-related proteins (TYR, TRP-1, DCT) in cells (P<0.01). In addition, the number of melanosomes was decreased and the dentrites formation of B16F10 cells was inhibited after NJVO treatment (P<0.01). In vivo, NJVO significantly reduced the pigment content in the zebrafish body (P<0.01).
CONCLUSION
NJVO effectively reversed SP/CORT-induced hyperpigmentation by suppressing the activity and expression of TYR and TRPs and inhibiting melanosome maturation in mouse B16F10 melanoma cells.
Animals
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Hyperpigmentation/psychology*
;
Zebrafish
;
Oils, Volatile/therapeutic use*
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Melanins/metabolism*
;
Humans
;
Monophenol Monooxygenase/metabolism*
;
Mice
;
Nardostachys/chemistry*
;
Substance P
;
Hydrocortisone
;
Skin Pigmentation/drug effects*
;
Cell Line, Tumor
;
Melanosomes/ultrastructure*
;
Microphthalmia-Associated Transcription Factor/metabolism*
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Melanoma, Experimental
;
Oxidoreductases/metabolism*
;
Intramolecular Oxidoreductases/metabolism*
7.Effect of ginsenoside Rb3 on experimental periodontitis in rats.
Hua LI ; Kang ZHANG ; Huijuan QU ; Honghai JI ; Minmin SUN
West China Journal of Stomatology 2025;43(5):711-721
OBJECTIVES:
This study aimed to explore the therapeutic effect and mechanism of ginsenoside Rb3 on experimental periodontitis and bone resorption in rats.
METHODS:
Male SD rats were randomly divided into a control group, a ligation group, an Rb3 group, and a doxycycline (Dox) group for in vivo experiments. A periodontitis model was established by ligating the maxillary second molar, and samples were collected after 3 weeks of drug treatment. Micro-CT assessment of alveolar bone resorption was performed, and hematoxylin-eosin (HE) staining was used to observe pathological changes in periodontal and visceral tissues. Tartrate resistant acid phosphatase (TRAP) staining was applied to detect the formation of osteoclasts in periodontal tissues, and enzyme-linked immunosorbent assay (ELISA) was adopted to detect the serum levels of interleukin (IL)-6, IL-8, immunoglobulin (Ig)M, and IgG. Quantitative polymerase chain reaction (qPCR) was employed to detect the expression of factors related to gingival inflammation and osteoclast formation. Immunofluorescence staining was used to detect phospho-extracellular signal-regulated kinase (p-ERK) expression. In vitro experiments were conducted by pretreating RAW264.7 cells with drugs and adding lipopolysaccharides (LPS) stimulation from Porphyromonas gingivalis (P. gingivalis). IL-1β and IL-6 mRNA expression was detected by qPCR, and Western blot was used to detect the effect of Rb3 on the mitogen-activated protein kinases (MAPKs) signaling pathway.
RESULTS:
Compared with the control group, the ligation group showed significant periodontitis and bone resorption. Compared with the ligation group, the Rb3 group showed a decrease in alveolar bone resorption and osteoclast formation; p-ERK/ERK ratio, IL-1β, IL-6, and nuclear factor of activated T cells (NFATc1) mRNA levels and downstream gene expression in periodontal tissues; serum IL-6, IL-8, IgG, and IgM levels. Rb3 reduced IL-8 and IL-1β mRNA expression levels and p-ERK/ERK and p-p38 MAPK/p38 MAPK ratios in RAW264.7 cells induced by P. gingivalis LPS stimulation.
CONCLUSIONS
Rb3 inhibits inflammation and bone resorption in experimental periodontitis in rats. Compared with Dox, Rb3 has better effects in inhibiting pro-inflammatory factors and osteoclast gene expression and may exert anti-inflammatory effects by activating the MAPK signaling pathway.
Animals
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Ginsenosides/therapeutic use*
;
Rats, Sprague-Dawley
;
Male
;
Periodontitis/pathology*
;
Rats
;
Osteoclasts/drug effects*
;
Interleukin-1beta/metabolism*
;
Interleukin-6/blood*
;
Mice
;
Alveolar Bone Loss
;
Interleukin-8/blood*
;
Immunoglobulin G/blood*
;
RAW 264.7 Cells
;
Transcription Factors
8.Advances in Clinical Application of Gastric Contrast-Enhanced Ultrasound for Gastric Cancer.
Guan-Mo LIU ; Hua LIANG ; Yang GUI ; Jie LI ; Xin YE ; Wei-Ming KANG
Acta Academiae Medicinae Sinicae 2025;47(5):716-724
Gastric contrast-enhanced ultrasound includes oral contrast-enhanced ultrasound (OCUS) and double contrast-enhanced ultrasound (DCEUS),which can provide valuable clinical information about tumor morphology,vascular characteristics,and treatment responses.OCUS can clearly identify the gastric wall structure and the extent and depth of lesions by applying oral contrast agents.DCEUS,based on OCUS combined with venography,can display the anatomical and perfusion characteristics of lesions.In recent years,gastric contrast agents and imaging techniques have developed rapidly.However,the clinical application of gastric contrast-enhanced ultrasound is still in the developmental stage.This article reviews the clinical status of OCUS and DCEUS in the screening,diagnosis,staging,pathological typing,and treatment evaluation of gastric cancer.Studies have shown that gastric contrast-enhanced ultrasound has high sensitivity and specificity in the assessment of diagnosis and T-staging of gastric cancer.Furthermore,gastric contrast-enhanced ultrasound has the advantages of being cost-effective,convenient,non-invasive,free from radiation exposure,real-time,and easy to repeat.In the diagnosis and treatment of gastric cancer,it is expected to become one of the important imaging assessment tools.
Humans
;
Stomach Neoplasms/diagnostic imaging*
;
Contrast Media
;
Ultrasonography/methods*
9.Chinese expert consensus on the diagnosis and treatment of traumatic supraorbital fissure syndrome (version 2024)
Junyu WANG ; Hai JIN ; Danfeng ZHANG ; Rutong YU ; Mingkun YU ; Yijie MA ; Yue MA ; Ning WANG ; Chunhong WANG ; Chunhui WANG ; Qing WANG ; Xinyu WANG ; Xinjun WANG ; Hengli TIAN ; Xinhua TIAN ; Yijun BAO ; Hua FENG ; Wa DA ; Liquan LYU ; Haijun REN ; Jinfang LIU ; Guodong LIU ; Chunhui LIU ; Junwen GUAN ; Rongcai JIANG ; Yiming LI ; Lihong LI ; Zhenxing LI ; Jinglian LI ; Jun YANG ; Chaohua YANG ; Xiao BU ; Xuehai WU ; Li BIE ; Binghui QIU ; Yongming ZHANG ; Qingjiu ZHANG ; Bo ZHANG ; Xiangtong ZHANG ; Rongbin CHEN ; Chao LIN ; Hu JIN ; Weiming ZHENG ; Mingliang ZHAO ; Liang ZHAO ; Rong HU ; Jixin DUAN ; Jiemin YAO ; Hechun XIA ; Ye GU ; Tao QIAN ; Suokai QIAN ; Tao XU ; Guoyi GAO ; Xiaoping TANG ; Qibing HUANG ; Rong FU ; Jun KANG ; Guobiao LIANG ; Kaiwei HAN ; Zhenmin HAN ; Shuo HAN ; Jun PU ; Lijun HENG ; Junji WEI ; Lijun HOU
Chinese Journal of Trauma 2024;40(5):385-396
Traumatic supraorbital fissure syndrome (TSOFS) is a symptom complex caused by nerve entrapment in the supraorbital fissure after skull base trauma. If the compressed cranial nerve in the supraorbital fissure is not decompressed surgically, ptosis, diplopia and eye movement disorder may exist for a long time and seriously affect the patients′ quality of life. Since its overall incidence is not high, it is not familiarized with the majority of neurosurgeons and some TSOFS may be complicated with skull base vascular injury. If the supraorbital fissure surgery is performed without treatment of vascular injury, it may cause massive hemorrhage, and disability and even life-threatening in severe cases. At present, there is no consensus or guideline on the diagnosis and treatment of TSOFS that can be referred to both domestically and internationally. To improve the understanding of TSOFS among clinical physicians and establish standardized diagnosis and treatment plans, the Skull Base Trauma Group of the Neurorepair Professional Committee of the Chinese Medical Doctor Association, Neurotrauma Group of the Neurosurgery Branch of the Chinese Medical Association, Neurotrauma Group of the Traumatology Branch of the Chinese Medical Association, and Editorial Committee of Chinese Journal of Trauma organized relevant experts to formulate Chinese expert consensus on the diagnosis and treatment of traumatic supraorbital fissure syndrome ( version 2024) based on evidence of evidence-based medicine and clinical experience of diagnosis and treatment. This consensus puts forward 12 recommendations on the diagnosis, classification, treatment, efficacy evaluation and follow-up of TSOFS, aiming to provide references for neurosurgeons from hospitals of all levels to standardize the diagnosis and treatment of TSOFS.
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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