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.Establishment and stress analysis of a finite element model for adolescent cervical disc herniation
Yuxin ZHAO ; Liang LIANG ; Feng JIN ; Yangyang XU ; Zhijie KANG ; Yuan FANG ; Yujie HE ; Xing WANG ; Haiyan WANG ; Xiaohe LI
Chinese Journal of Tissue Engineering Research 2025;29(3):448-454
BACKGROUND:Cervical disc herniation can cause pain in the neck and shoulder area,as well as radiating pain in the upper limbs.The incidence rate is increasing year by year and tends to affect younger individuals.Fully understanding the biomechanical characteristics of the cervical spine in adolescents is of great significance for preventing and delaying the onset of cervical disc herniation in this age group. OBJECTIVE:To reconstruct cervical spine models for both healthy adolescents and adolescent patients with cervical disc herniation utilizing finite element analysis techniques,to analyze the motion range of the C1-T1 cervical vertebrae as well as the biomechanical characteristics of the annulus fibrosus,nucleus pulposus,endplates,and the cartilage of the small joints. METHODS:A normal adolescent's cervical spine and an adolescent patient with cervical disc herniation were selected in this study.The continuous scan cervical spine CT raw image data were imported into Mimics 21.0 in DICOM format.The C1-T1 vertebrae were reconstructed separately.Subsequently,the established models were imported into the 3-Matic software for disc reconstruction.The perfected models were then imported into Hypermesh software for meshing of the vertebrae,nucleus pulposus,annulus fibrosus,and ligaments,creating valid geometric models.After assigning material properties,the final models were imported into ABAQUS software to observe the joint motion range of the C1-C7 cervical vertebrae segments under different conditions,and to analyze the biomechanical characteristics of the annulus fibrosus,nucleus pulposus,endplates,and small joint cartilage of each cervical spine segment. RESULTS AND CONCLUSION:(1)In six different conditions,the joint motion range of the C1 vertebra in the cervical spine models of both normal adolescent and adolescent patient with cervical disc herniation was higher than that of the other vertebrae.Additionally,the joint motion range of each cervical spine segment in normal adolescent was greater than that in adolescent patient with cervical disc herniation.(2)In the cervical spine model of normal adolescent,the maximum stress values in the annulus fibrosus and nucleus pulposus were found on the left side during C2-3 flexion conditions(0.43 MPa and 0.17 MPa,respectively).In the cervical spine model of adolescent patient with cervical disc herniation,the maximum stress values were found on the left side during C7-T1 flexion conditions(0.54 MPa and 0.18 MPa,respectively).(3)In the cervical spine model of normal adolescent,the maximum stress value on the endplate was found on the left side of the upper endplate of C3 during flexion conditions(1.46 MPa).In the model of adolescent patient with cervical disc herniation,the maximum stress value on the endplate was found on the left side of the lower endplate of C7 during flexion conditions(1.32 MPa).(4)In the cervical spine model of normal adolescent,the maximum stress value in the small joint cartilage was found in the C2-3 left rotation conditions(0.98 MPa).In adolescent patient with cervical disc herniation,the stress in the small joint cartilage significantly increased under different conditions,especially in C1-2,with the maximum stress found during left flexion(3.50 MPa).(5)It is concluded that compared to normal adolescent,adolescent patient with cervical disc herniation exhibits altered cervical curvature and a decrease in overall joint motion range in the cervical spine.In adolescent with cervical disc herniation,there is a significant increase in stress on the annulus fibrosus,nucleus pulposus,and endplates in the C7-T1 segment.The stress on the left articular cartilage of the C1-2 is notable.Abnormal cervical curvature may be the primary factor causing these stress changes.
3.Correlation between brain white matter lesions and insulin resistance in non-diabetic elderly individuals based on magnetic resonance imaging
Mei LI ; Fang YUAN ; Xizi XING ; Feng XIE ; Hua ZHANG
Chinese Journal of Radiological Health 2025;34(1):96-101
Objective To investigate the relationship between brain white matter lesions (WML) and triglyceride glucose (TyG) index in non-diabetic elderly individuals based on magnetic resonance imaging. Methods A total of 523 non-diabetic elderly individuals aged ≥ 60 years were selected from Jinan, Shandong Province, China from June 2018 to December 2019. According to the quartiles of TyG index, there were 133 participants in the first quartile (Q1) group, 127 in the second quartile (Q2) group, 132 in the third quartile (Q3) group, and 131 in the fourth quartile (Q4) group. All participants underwent brain magnetic resonance imaging to evaluate paraventricular, deep, and total WML volumes, as well as Fazekas scores. Results Compared with Q1, Q2, and Q3 groups, Q4 group showed significant increase in periventricular, deep, and total WML volumes (P < 0.05). The proportion of participants with a Fazekas score ≥ 2 in the periventricular, deep, and total WML was higher in the Q4 group compared with the Q1 and Q2 groups (P < 0.05). The proportion of participants with a Fazekas score ≥ 2 in deep WML was higher in Q4 group than in Q3 group (P < 0.05). TyG index was significantly positively correlated with periventricular, deep, and total WML volumes (r = 0.401, 0.405, and 0.445, P < 0.001). After adjusting for confounding factors, TyG index was still significantly positively correlated with periventricular, deep, and total WML volumes (P < 0.001). Logistic regression analysis showed that compared with Q1 group, the risk of Fazekas score ≥ 2 in periventricular WML was 1.950-fold (95% confidence interval [CI]: 1.154-3.294, P = 0.013) in Q3 group and 3.411-fold (95% CI: 1.984-5.863, P < 0.001) in Q4 group, the risk of Fazekas score ≥ 2 in total WML was 2.529-fold (95%CI: 1.444-4.430, P = 0.001) in Q3 group and 4.486-fold (95%CI: 2.314-8.696, P < 0.001) in Q4 group. The risk of Fazekas score ≥ 2 in deep WML was 2.953-fold (95%CI: 1.708-5.106, P < 0.001) in Q4 group compared with Q1 group. Conclusion Increased TyG index is an independent risk factor for WML in non-diabetic elderly individuals.
4.Reference values of carotid intima-media thickness and arterial stiffness in Chinese adults based on ultrasound radio frequency signal: A nationwide, multicenter study
Changyang XING ; Xiujing XIE ; Yu WU ; Lei XU ; Xiangping GUAN ; Fan LI ; Xiaojun ZHAN ; Hengli YANG ; Jinsong LI ; Qi ZHOU ; Yuming MU ; Qing ZHOU ; Yunchuan DING ; Yingli WANG ; Xiangzhu WANG ; Yu ZHENG ; Xiaofeng SUN ; Hua LI ; Chaoxue ZHANG ; Cheng ZHAO ; Shaodong QIU ; Guozhen YAN ; Hong YANG ; Yinjuan MAO ; Weiwei ZHAN ; Chunyan MA ; Ying GU ; Wu CHEN ; Mingxing XIE ; Tianan JIANG ; Lijun YUAN
Chinese Medical Journal 2024;137(15):1802-1810
Background::Carotid intima-media thickness (IMT) and diameter, stiffness, and wave reflections, are independent and important clinical biomarkers and risk predictors for cardiovascular diseases. The purpose of the present study was to establish nationwide reference values of carotid properties for healthy Chinese adults and to explore potential clinical determinants.Methods::A total of 3053 healthy Han Chinese adults (1922 women) aged 18-79 years were enrolled at 28 collaborating tertiary centers throughout China between April 2021 and July 2022. The real-time tracking of common carotid artery walls was achieved by the radio frequency (RF) ultrasound system. The IMT, diameter, compliance coefficient, β stiffness, local pulse wave velocity (PWV), local systolic blood pressure, augmented pressure (AP), and augmentation index (AIx) were then automatically measured and reported. Data were stratified by age groups and sex. The relationships between age and carotid property parameters were analyzed by Jonckheere-Terpstra test and simple linear regressions. The major clinical determinants of carotid properties were identified by Pearson’s correlation, multiple linear regression, and analyses of covariance.Results::All the parameters of carotid properties demonstrated significantly age-related trajectories. Women showed thinner IMT, smaller carotid diameter, larger AP, and AIx than men. The β stiffness and PWV were significantly higher in men than women before forties, but the differences reversed after that. The increase rate of carotid IMT (5.5 μm/year in women and 5.8 μm/year in men) and diameter (0.03 mm/year in both men and women) were similar between men and women. For the stiffness and wave reflections, women showed significantly larger age-related variations than men as demonstrated by steeper regression slopes (all P for age by sex interaction <0.05). The blood pressures, body mass index (BMI), and triglyceride levels were identified as major clinical determinants of carotid properties with adjustment of age and sex. Conclusions::The age- and sex-specific reference values of carotid properties measured by RF ultrasound for healthy Chinese adults were established. The blood pressures, BMI, and triglyceride levels should be considered for clinical application of corresponding reference values.
5.N-butyl-9H-pyrimido4,5-bindole-2-carboxamide inhibits macrophage foaming and pyroptosis via NLRP3/caspase-1
Zhi-Yun SHU ; Zi-Xu HUYAN ; Wen-Qing ZHANG ; Shi-Shun XIE ; Hong-Yuan CHENG ; Guo-Xing XU ; Xiang-Jun LI
Chinese Pharmacological Bulletin 2024;40(6):1035-1041
Aim To design the pyrimidoindole deriva-tive N-butyl-9H-pyrimido[4,5-b]indole-2-carboxamide(BFPI)and synthesize it to investigate whether it in-hibits macrophage pyroptosis and foaming effects through the NLRP3/Caspase-1 pathway.Methods BFPI was synthesized using 2,4,6-triethoxycarbonyl-l,3,5-triazine and 2-aminoindole as starting materials and structurally characterized by 1H NMR,13C NMR,and ESI-MS.The in vitro cultured mouse monocyte macro-phage cell line RAW264.7 was divided into blank,model(PA)and therapeutic(BFPI)groups,and the cells in each group were treated with the corresponding culture medium for 24 h.The proliferative viability was detected by MTT assay,and the formation of intracel-lular lipid droplets was detected by oil red O staining,and NLRP3 was detected by Western-blot and RT-qPCR,caspase-1 and MCP-1 mRNA and protein ex-pression levels by Western blot and RT-qPCR.Results Compared with the blank group,the proliferation vi-ability of cells in the model group significantly de-creased and the formation of lipid droplets significantly increased;compared with the model group,the prolif-eration viability of cells in the treatment group signifi-cantly increased and the formation of lipid droplets sig-nificantly decreased,and the differences were statisti-cally significant(P<0.01);compared with the blank group,the cellular NLRP3,caspase-1 and MCP-1 mR-NA and protein expression levels of cells in the model group significantly increased;compared with the model group,the expression levels of the above indexes of the cells in the treatment group significantly decreased,and the difference was statistically significant(P<0.01).Conclusions BFPI contributes to delaying macrophage-derived foam cell formation during athero-genesis by inhibiting macrophage NLRP3,caspase-1,and MCP-1 expression and thereby promoting their pro-liferation and inhibiting lipid phagocytosis.
6.Research progress on neurobiological mechanisms underlying antidepressant effect of ketamine
Dong-Yu ZHOU ; Wen-Xin ZHANG ; Xiao-Jing ZHAI ; Dan-Dan CHEN ; Yi HAN ; Ran JI ; Xiao-Yuan PAN ; Jun-Li CAO ; Hong-Xing ZHANG
Chinese Pharmacological Bulletin 2024;40(9):1622-1627
Major depressive disorder(MDD)is a prevalent con-dition associated with substantial impairment and low remission rates.Traditional antidepressants demonstrate delayed effects,low cure rate,and inadequate therapeutic effectiveness for man-aging treatment-resistant depression(TRD).Several studies have shown that ketamine,a non-selective N-methyl-D-aspartate receptor(NMDAR)antagonist,can produce rapid and sustained antidepressant effects.Ketamine has demonstrated efficacy for reducing suicidality in TRD patients.However,the pharmaco-logical mechanism for ketamine's antidepressant effects remains incompletely understood.Previous research suggests that the an-tidepressant effects of ketamine may involve the monoaminergic,glutamatergic and dopaminergic systems.This paper provides an overview of the pharmacological mechanism for ketamine's anti-depressant effects and discuss the potential directions for future research.
7.Mechanism of Toddalia asiatica in treatment of osteodestruction in rheumatoid arthritis based on network pharmacology and experimental verification
Lu JIANG ; Zong-Xing ZHANG ; Wei-Yi LI ; Dao-Zhong LIU ; Zhuo-Ma BAO ; Qin-Yun NIE ; Lin YUAN
Chinese Pharmacological Bulletin 2024;40(10):1979-1990
Aim To investigate the effect of Toddalia asiatica(TA)on bone destruction in rheumatoid ar-thritis(RA)and its possible mechanism by network pharmacology and in vitro experiments.Methods The active components and targets of TA against RA bone damage were analyzed by network pharmacology.Mo-lecular docking was performed by using AutoDock and PyMOL software pairs.MC3T3-e1 cells were cultured in vitro,and the effect of Toddalia asiatica alcohol ex-tract(TAAE)on cell viability was detected by CCK-8,and appropriate drug concentration and intervention time were screened.The osteoblast model was induced by osteogenic induction medium,and the osteogenic differentiation was detected by ALP staining,activity detection and alizarin red staining.The expression of pathway-related proteins Wnt3a and β-catenin was de-tected by Western blot,and the pathway inhibitor DKK-1 was used to further verify whether TAAE regulated osteoblast differentiation through the Wnt/β-catenin signaling pathway.Results A total of 158 anti-RA bone destruction targets and 56 core targets were se-lected.The enrichment of KEGG signaling pathway mainly included cancer pathway,phosphatidylinositol 3-kinase/protein kinase B signaling pathway and cAMP signaling pathway.The results of CCK-8 showed that 1 g·L-1 TAAE could significantly improve cell survival rate.The results of ALP staining and ALP activity de-tection showed that TAAE could significantly increase the staining positive rate and ALP activity of cells in-duced by osteogenic induction medium.Western blot showed that TAAE could increase the expression of Wnt3a and β-catenin.The expression of these proteins decreased after DKK-1 inhibitors were used.Conclu-sion TAAE can regulate osteoblast differentiation through Wnt/β-catenin signaling pathway to treat os-teodestruction in rheumatoid arthritis.
8.Short term follow-up of femoral neck dynamic cross screw system and threaded cannulated screw in the treatment of vertically unstable femoral neck fractures
Qiang WANG ; Xin LYU ; Xing-Ye LI ; Jin-Yuan LIU
China Journal of Orthopaedics and Traumatology 2024;37(5):458-463
Objective To analyze and compare the clinical effects of femoral neck dynamic cross screw system(FNS)and cannulated screws(CS)in the treatment of vertically unstable femoral neck fractures.Methods The clinical data and short-term follow-up results of 40 patients with vertically unstable femoral neck fractures admitted from July 2020 to August 2021 were retrospectively analyzed.According to different internal fixation methods,40 patients were divided into two groups,20 cases in FNS group included 11 males and 9 females with a median of 58.5(50.3,62.5)years old,and 20 in CS group included 9 males and 11 females with a median of 52.0(40.5,58.0)years old.The operation time,knife edge length,blood loss and treatment cost of two gruops were observed and compared.The postoperative fracture healing and internal fixation were evaluated with X-ray imaging data,and the femoral neck shortening of the affected side was measured.The incidence of thigh irritation,the time of partial weight bearing and full weight bearing,early necrosis of femoral head,reoperation revision and Harris scores were compared between two groups.Results FNS group was followed up for 18.0(15.0,19.0)months,CS group for 17.0(15.0,18.8)months.There was no significant difference in operation time,incision length and blood loss between two groups(P>0.05).The cost of diagnosis and treatment in FNS group was higher than that in CS group(P<0.001).In FNS group,there was no irritation sign of the affected side thigh,while in CS group,there were 6 cases with discomfort or irritation sign of the lateral thigh(P<0.05).The average time of partial weight bearing activity in CS group was later than that in FNS group(P<0.05);However,there was no significant difference in the activity time of complete weight bearing between two groups(P=0.011>0.05).At the last follow-up,the shortened length of the affected femoral neck in CS group was greater than that in FNS group(P<0.05).There was no early necrosis of femoral head and reoperation in both groups.There was no significant difference in Harris score be-tween two groups 12 months after operation(P>0.05).Conclusion FNS treatment of vertically unstable femoral neck fractures can significantly reduce the incidence of lateral thigh irritation sign,and effectively reduce the postoperative shortening rate of vertically unstable femoral neck fractures,which can provide a relatively stable anti rotation force and anti cutting force,so that patients can go to the ground relatively early,which is conducive to the recovery of the affected hip joint function after surgery.It is a new option for the surgical treatment of vertically unstable femoral neck fractures.However,due to the high cost of treat-ment,In clinical practice,appropriate surgical treatment is selected according to the actual situation.
9.Curative effect analysis of anterior cervical discectomy and fusion in patients with cervical spondylosis of vertebral artery type
Yi-Xiang AI ; Jian-Tao LIU ; Ding-Jun HAO ; Xi GONG ; Yi-Han ZHU ; Xing-Yuan LI ; Xi-Wei ZHANG ; Kao WANG ; Jia-Jun SUN ; Shu-Yuan ZHANG
China Journal of Orthopaedics and Traumatology 2024;37(7):670-675
Objective To investigate the clinical effect of anterior cervical discectomy and fusion(ACDF)in the treatment of cervical spondylosis of vertebral artery type(CSA).Methods The clinical data of 42 patients with CSA from January 2020 to January 2022 were retrospectively analyzed.There were 25 males and 17 females,aged from 30 to 74 years old with an average of(53.9±11.0)years old.There were 18 cases with single-segment lesions,17 cases with two-segment lesions,and 7 cases with three-segment lesions.The American Academy of Otolaryngology-Head and Neck Surgery's Hearing and Balance Committee score(CHE),the Neck Disability Index(NDI)and the cervical curvature Cobb angle were recorded before surgery and after surgery at 6 months.Results All 42 ACDF patients were followed up for 6 to 30 months with an average of(14.0±5.2)months.The operative time ranged from 95 to 220 min with an average of(160.38±36.77)min,the intraoperative blood loss ranged from 30 to 85 ml with an average of(53.60±18.98)ml.Tow patients had mild postoperative dysphagia,which improved with symptomatic treatment such as nebulized inhalation.CHE score decreased from(4.05±0.96)preoperatively to(2.40±0.70)at 6 months postoperatively(t=12.97,P<0.05).The number of improved vertigo at 6 months postoperatively was 38,with an im-provement rate of 90.5%.NDI score was reduced from(34.43±8.04)preoperatively to(20.76±3.91)at 6 months postopera-tively(t=1 1.83,P<0.05).The cervical curvature Cobb angle improved from(8.04±6.70)° preoperatively to(12.42±5.23)° at 6 months postoperatively(t=-15.96,P<0.05).Conclusion The ACDF procedure has outstanding clinical efficacy in treating CSA.The operation can rapidly relieve patients'episodic vertigo symptoms by relieving bony compression and reconstructing cervical curvature.However,it is necessary to strictly grasp the indications for surgery and clarify the causes of vertigo in pa-tients,and ACDF surgery is recommended for CSA patients for whom conservative treatment is ineffective.
10.Transcatheter edge-to-edge repair in acute mitral regurgitation following acute myocardial infarction:a case report
Tong KAN ; Xing-Hua SHAN ; Song-Hua LI ; Fei-Fei DONG ; Ke-Yu CHEN ; Hua WANG ; Rui BAO ; Sai-Nan GU ; Yong-Wen QIN ; Yuan BAI
Chinese Journal of Interventional Cardiology 2024;32(11):658-660
Acute mitral regurgitation(MR)in the setting of myocardial infarction(MI)may be the result of papillary muscle rupture(PMR).The clinical presentation can be catastrophic,with refractory cardiogenic shock.This condition is associated with high morbidity and mortality.Transcatheter edge-to-edge repair(TEER)has become increasingly common in treating severe mitral regurgitation.This case details a successful TEER is feasible and safe in patients with acute MR following MI.TEER is an emerging treatment option in this clinical scenario that should be taken into consideration.

Result Analysis
Print
Save
E-mail