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.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.
3.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.
4.Digital study on proximal clavicle anatomical plate based on 3D printing technology
Yi ZHENG ; Xing-Guo ZHENG ; Jia-Kai ZHANG ; Jun-Long WU ; Xin-Hua YUAN
China Journal of Orthopaedics and Traumatology 2024;37(3):278-280
Objective To explore feasibility of 3D metal printing technology combined with virtual design proximal clavicle anatomical plate.Methods A 52-year-old male healthy volunteer was retrospectively selected to design proximal clavicle anatomical plate system by using Mimics15.01,NX12.0 and other software.STL data were input into 3D printer to print 1∶1 clavicle model and proximal clavicle anatomical plate.The fit of the plate was tested in vitro and the accuracy of screw position was evaluated by imaging.Printing time of model,nail path design and fabrication time of the anatomical plate at proximal clavicle were recorded.Results The 3D metal printing proximal clavicle anatomical plate fitted well to clavicle model,orienta-tion of proximal clavicle locking screw was accurate,and X-ray and CT scan showed the screw position was good.Printing time of model,the time of nail path design,and the time of making anatomical plate of proximal clavicle were 120,15 and 300 min respectively.Conclusion The proximal clavicular anatomical plate system based on 3D metal printing technology could achieve good lamination of proximal clavicular fracture plate and precise screw placement,providing a new and accurate surgical method for the treatment of the proximal clavicular fracture.
5.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.
6.Cases Analysis of Hemoglobin H Disease Caused by HBA2:c.2T>C and HBA2:c.2delT Mutations
Qiu-Hua WANG ; Xing-Yuan CHEN ; Ning TANG ; Ti-Zhen YAN ; Jun HUANG ; Qing-Yan ZHONG ; Shi-Qiang LUO
Journal of Experimental Hematology 2024;32(2):520-524
Objective:To investigate two cases of rare pathogenic genes,initiation codon mutations in HBA2 gene,combined with Southeast Asian deletion and their family members to understand the relationship of HBA2:c.2T>C and HBA2:c.2delT mutations with clinical phenotype.Methods:The peripheral blood of family members was obtained for blood cell analysis and capillary electrophoresis hemoglobin analysis.Gap-PCR and reverse dot blotting(RDB)were used to detect common types of mutations in α-thalassaemia gene.Sanger sequencing was used to analyze HBA1 and HBA2 gene sequence.Results:Two proband genotypes were identified as--SEA/αα with HBA2:c.2T>C and--SEA/αα with HBA2:c.2delT.HBA2:c.2T>C/WT and HBA2:c.2delT/WT was detected in family members.They all presented with microcytic hypochromic anemia.Conclusion:When HBA2:c.2T>C and HBA2:c.2delT are heterozygous that can lead to static α-thalassemia phenotype,and when combined with mild α-thalassemia,they can lead to the clinical manifestations of hemoglobin H disease.This study provides a basis for genetic counseling.
7.Clinical effects of Polygonum cuspidatum on patients with type 2 diabetes mellitus of Dampness-Heat Pattern
Yuan-Ying XU ; Wen-Wen KONG ; Hong-Ping YIN ; Hui-Hui ZHANG ; Xing-Hua CAI ; Bi-Lin XU ; Wen-Jun SHA ; Tao LEI
Chinese Traditional Patent Medicine 2024;46(8):2596-2600
AIM To explore the clinical effects of Polygonum cuspidatum Sieb.et Zucc.on patients with type 2 diabetes mellitus of Dampness-Heat Pattern.METHODS One hundred and forty patients were randomly assigned into control group(70 cases)for 8-week intervention of conventional treatment,and observation group(70 cases)for 8-week intervention of both P.cuspidatum granules and conventional treatment.The changes in body weight,BMI,blood glucose indices(FBG,2 h PG,HbA1C,GA),blood lipid indices(TC,TG,HDL-C,LDL-C,ApoA-I,ApoB,ApoA,ApoE,sdLDL-C),liver function indices(ALT,AST),fatty liver progression,TyG,HSI,TCM syndrome score and effects were detected.RESULTS The observation group demonstrated higher total effective rates of TCM syndromes than the control group(P<0.01),along with slighter fatty liver progression(P<0.01).After the treatment,the observation group displayed decreased body weight,BMI,FBG,GA,TG,ApoE,TyG,HSI,ALT and TCM syndrome score(P<0.05,P<0.01),and 2 h PG,TyG,HSI,ALT,TCM syndrome score were lower than those in the control group(P<0.05,P<0.01).CONCLUSION For the patients with type 2 diabetes mellitus of Dampness-Heat Pattern,P.cuspidatum can improve glucose and lipid metabolism disorders,which is worthy of clinical popularization and application.
8.Antimicrobial resistance of bacteria from blood specimens:surveillance re-port from Hunan Province Antimicrobial Resistance Surveillance System,2012-2021
Hong-Xia YUAN ; Jing JIANG ; Li-Hua CHEN ; Chen-Chao FU ; Chen LI ; Yan-Ming LI ; Xing-Wang NING ; Jun LIU ; Guo-Min SHI ; Man-Juan TANG ; Jing-Min WU ; Huai-De YANG ; Ming ZHENG ; Jie-Ying ZHOU ; Nan REN ; An-Hua WU ; Xun HUANG
Chinese Journal of Infection Control 2024;23(8):921-931
Objective To understand the change in distribution and antimicrobial resistance of bacteria isolated from blood specimens of Hunan Province,and provide for the initial diagnosis and treatment of clinical bloodstream infection(BSI).Methods Data reported from member units of Hunan Province Antimicrobial Resistance Survei-llance System from 2012 to 2021 were collected.Bacterial antimicrobial resistance surveillance method was imple-mented according to the technical scheme of China Antimicrobial Resistance Surveillance System(CARSS).Bacteria from blood specimens and bacterial antimicrobial susceptibility testing results were analyzed by WHONET 5.6 soft-ware and SPSS 27.0 software.Results A total of 207 054 bacterial strains were isolated from blood specimens from member units in Hunan Province Antimicrobial Resistance Surveillance System from 2012 to 2021,including 107 135(51.7%)Gram-positive bacteria and 99 919(48.3%)Gram-negative bacteria.There was no change in the top 6 pathogenic bacteria from 2012 to 2021,with Escherichia coli(n=51 537,24.9%)ranking first,followed by Staphylococcus epidermidis(n=29 115,14.1%),Staphylococcus aureus(n=17 402,8.4%),Klebsiella pneu-moniae(17 325,8.4%),Pseudomonas aeruginosa(n=4 010,1.9%)and Acinetobacter baumannii(n=3 598,1.7%).The detection rate of methicillin-resistant Staphylococcus aureus(MRSA)decreased from 30.3%in 2015 to 20.7%in 2021,while the detection rate of methicillin-resistant coagulase-negative Staphylococcus(MRCNS)showed an upward trend year by year(57.9%-66.8%).No Staphylococcus was found to be resistant to vancomy-cin,linezolid,and teicoplanin.Among Gram-negative bacteria,constituent ratios of Escherichia coli and Klebsiella pneumoniae were 43.9%-53.9%and 14.2%-19.5%,respectively,both showing an upward trend(both P<0.001).Constituent ratios of Pseudomonas aeruginosa and Acinetobacter baumannii were 3.6%-5.1%and 3.0%-4.5%,respectively,both showing a downward trend year by year(both P<0.001).From 2012 to 2021,resistance rates of Escherichia coli to imipenem and ertapenem were 1.0%-2.0%and 0.6%-1.1%,respectively;presenting a downward trend(P<0.001).The resistant rates of Klebsiella pneumoniae to meropenem and ertapenem were 7.4%-13.7%and 4.8%-6.4%,respectively,presenting a downward trend(both P<0.001).The resistance rates of Pseudomonas aeruginosa and Acinetobacter baumannii to carbapenem antibiotics were 7.1%-15.6%and 34.7%-45.7%,respectively.The trend of resistance to carbapenem antibiotics was relatively stable,but has de-creased compared with 2012-2016.The resistance rates of Escherichia coli to the third-generation cephalosporins from 2012 to 2021 were 41.0%-65.4%,showing a downward trend year by year.Conclusion The constituent ra-tio of Gram-negative bacillus from blood specimens in Hunan Province has been increasing year by year,while the detection rate of carbapenem-resistant Gram-negative bacillus remained relatively stable in the past 5 years,and the detection rate of coagulase-negative Staphylococcus has shown a downward trend.
9.Antimicrobial resistance of bacteria from cerebrospinal fluid specimens:surveillance report from Hunan Province Antimicrobial Resistance Survei-llance System,2012-2021
Jun LIU ; Li-Hua CHEN ; Chen-Chao FU ; Chen LI ; Yan-Ming LI ; Xing-Wang NING ; Guo-Min SHI ; Jing-Min WU ; Huai-De YANG ; Hong-Xia YUAN ; Ming ZHENG ; Nan REN ; An-Hua WU ; Xun HUANG ; Man-Juan TANG
Chinese Journal of Infection Control 2024;23(8):932-941
Objective To investigate changes in the distribution and antimicrobial resistance of bacteria isolated from cerebrospinal fluid(CSF)specimens in Hunan Province,and provide reference for correct clinical diagnosis and rational antimicrobial use.Methods Data reported by member units of Hunan Province Antimicrobial Resistance Surveillance System from 2012 to 2021 were collected according to China Antimicrobial Resistance Surveillance Sys-tem(CARSS)technical scheme.Data of bacteria isolated from CSF specimens and antimicrobial susceptibility tes-ting results were analyzed with WHONET 5.6 and SPSS 20.0 software.Results A total of 11 837 bacterial strains were isolated from CSF specimens from member units of Hunan Province Antimicrobial Resistance Surveillance Sys-tem from 2012 to 2021.The top 5 strains were coagulase-negative Staphylococcus(n=6 397,54.0%),Acineto-bacter baumannii(n=764,6.5%),Staphylococcus aureus(n=606,5.1%),Enterococcus faecium(n=465,3.9%),and Escherichia coli(n=447,3.8%).The detection rates of methicillin-resistant coagulase-negative Staphyloco-ccus(MRCNS)and methicillin-resistant Staphylococcus aureus(MRSA)were 58.9%-66.3%and 34.4%-62.1%,respectively.No Staphylococcus spp.were found to be resistant to vancomycin,linezolid,and teicoplanin.The de-tection rate of Enterococcus faecium was higher than that of Enterococcus faecalis,and the resistance rates of En-terococcus f aecium to penicillin,ampicillin,high concentration streptomycin and levofloxacin were all higher than those of Enterococcus faecalis(all P=0.001).Resistance rate of Streptococcus pneumoniae to penicillin was 85.0%,at a high level.Resistance rate of Escherichia coli to ceftriaxone was>60%,while resistance rates to enzyme inhibitors and carbapenem antibiotics were low.Resistance rate of Klebsiella pneumoniae to ceftriaxone was>60%,to en-zyme inhibitors piperacillin/tazobactam and cefoperazone/sulbactam was>30%,to carbapenem imipenem and me-ropenem was about 30%.Resistance rates of Acinetobacter baumannii to most tested antimicrobial agents were>60%,to imipenem and meropenem were 59.0%-79.4%,to polymyxin B was low.Conclusion Among the bac-teria isolated from CSF specimens,coagulase-negative Staphylococcus accounts for the largest proportion,and the overall resistance of pathogenic bacteria is relatively serious.Bacterial antimicrobial resistance surveillance is very important for the effective treatment of central nerve system infection.
10.Antimicrobial resistance of bacteria from intensive care units:surveillance report from Hunan Province Antimicrobial Resistance Surveillance Sys-tem,2012-2021
Li-Hua CHEN ; Chen-Chao FU ; Chen LI ; Yan-Ming LI ; Jun LIU ; Xing-Wang NING ; Guo-Min SHI ; Jing-Min WU ; Huai-De YANG ; Hong-Xia YUAN ; Ming ZHENG ; Nan REN ; Xun HUANG ; An-Hua WU ; Jian-Dang ZHOU
Chinese Journal of Infection Control 2024;23(8):942-953
Objective To investigate the distribution and antimicrobial susceptibility of clinically isolated bacteria from intensive care units(ICUs)in hospitals of Hunan Province Antimicrobial Resistance Surveillance System from 2012 to 2021.Methods According to China Antimicrobial Resistance Surveillance System,data of clinically isolated bacterial strains and antimicrobial susceptibility testing results of bacteria from ICUs reported by all member units of Hunan Province Antimicrobial Resistance Surveillance System were analyzed with WHONET 2022 software.Results From 2012 to 2021,the total number of bacteria isolated from ICUs of member units of the Hunan Province Antimi-crobial Resistance Surveillance System was 5 777-22 369,with Gram-negative bacteria accounting for 76.1%-78.0%annually.Staphylococcus aureus ranked first among isolated Gram-positive bacteria each year.The top 5 bacteria among Gram-negative bacteria were Acinetobacter baumannii,Klebsiella pneumoniae,Escherichia coli,Pseudo-monas aeruginosa,and Stenotrophomonas maltophilia.Detection rate of methicillin-resistant Staphylococcus aureus showed a downward trend year by year.No Staphylococcus spp.were found to be resistant to vancomycin,teico-planin and linezolid.Detection rates of vancomycin-resistant Enterococcus faecalis and vancomycin-resistant Entero-coccus faecium were 0.6-1.1%and 0.6%-2.2%,respectively.Resistance rates of Escherichia coli and Kleb-siella pneumoniae to imipenem were 3.1%-5.7%and 7.7%-20.9%,respectively.Resistance rates of Pseudo-monasaeruginosa and Acinetobacter baumannii to imipenem were 24.6%-40.1%and 76.1%-80.9%,respective-ly.Detection rates of carbapenem-resistant Pseudomonas aeruginosa declined year by year.Acinetobacter baumannii maintained high susceptibility to polymyxin B,with resistance rate<10%.Conclusion Antimicrobial resistance of bacteria from ICUs is serious.Carbapenem-resistant Enterobacteriales has an upward trend after 2019.It is nece-ssary to strengthen the surveillance of bacterial resistance and carry out multidisciplinary collaboration.

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