1.Structural and Spatial Analysis of The Recognition Relationship Between Influenza A Virus Neuraminidase Antigenic Epitopes and Antibodies
Zheng ZHU ; Zheng-Shan CHEN ; Guan-Ying ZHANG ; Ting FANG ; Pu FAN ; Lei BI ; Yue CUI ; Ze-Ya LI ; Chun-Yi SU ; Xiang-Yang CHI ; Chang-Ming YU
Progress in Biochemistry and Biophysics 2025;52(4):957-969
ObjectiveThis study leverages structural data from antigen-antibody complexes of the influenza A virus neuraminidase (NA) protein to investigate the spatial recognition relationship between the antigenic epitopes and antibody paratopes. MethodsStructural data on NA protein antigen-antibody complexes were comprehensively collected from the SAbDab database, and processed to obtain the amino acid sequences and spatial distribution information on antigenic epitopes and corresponding antibody paratopes. Statistical analysis was conducted on the antibody sequences, frequency of use of genes, amino acid preferences, and the lengths of complementarity determining regions (CDR). Epitope hotspots for antibody binding were analyzed, and the spatial structural similarity of antibody paratopes was calculated and subjected to clustering, which allowed for a comprehensively exploration of the spatial recognition relationship between antigenic epitopes and antibodies. The specificity of antibodies targeting different antigenic epitope clusters was further validated through bio-layer interferometry (BLI) experiments. ResultsThe collected data revealed that the antigen-antibody complex structure data of influenza A virus NA protein in SAbDab database were mainly from H3N2, H7N9 and H1N1 subtypes. The hotspot regions of antigen epitopes were primarily located around the catalytic active site. The antibodies used for structural analysis were primarily derived from human and murine sources. Among murine antibodies, the most frequently used V-J gene combination was IGHV1-12*01/IGHJ2*01, while for human antibodies, the most common combination was IGHV1-69*01/IGHJ6*01. There were significant differences in the lengths and usage preferences of heavy chain CDR amino acids between antibodies that bind within the catalytic active site and those that bind to regions outside the catalytic active site. The results revealed that structurally similar antibodies could recognize the same epitopes, indicating a specific spatial recognition between antibody and antigen epitopes. Structural overlap in the binding regions was observed for antibodies with similar paratope structures, and the competitive binding of these antibodies to the epitope was confirmed through BLI experiments. ConclusionThe antigen epitopes of NA protein mainly ditributed around the catalytic active site and its surrounding loops. Spatial complementarity and electrostatic interactions play crucial roles in the recognition and binding of antibodies to antigenic epitopes in the catalytic region. There existed a spatial recognition relationship between antigens and antibodies that was independent of the uniqueness of antibody sequences, which means that antibodies with different sequences could potentially form similar local spatial structures and recognize the same epitopes.
2.Comparison of the predictive value of new simplified insulin resistance assessment indexes in identifying left ventricular subclinical dysfunction in T2DM patients
Yan-Yan CHEN ; Meng-Ying LI ; Jie ZHOU ; Jian-Fang FU ; Ying ZHANG ; Yi WANG ; Cheng WANG ; Xiang-Yang LIU ; Sheng-Jun TA ; Li-Wen LIU ; Ze-Ping LI ; Xiao-Miao LI
Medical Journal of Chinese People's Liberation Army 2024;49(2):137-143
Objective To investigate the predictive value of new simplified insulin resistance(IR)assessment indexes in identifying subclinical left ventricular systolic function impairment in patients with type 2 diabetes mellitus(T2DM).Methods A total of 150 T2DM patients with preserved left ventricular ejection fraction(LVEF≥50%)who were admitted to Department of Endocrinology of the First Affiliated Hospital of Air Force Medical University from June 2021 to December 2021 were retrospectively analyzed.All patients underwent two-dimensional speckle tracking echocardiography to measure left ventricular global longitudinal strain(GLS).According to GLS value,the subjects were divided into the normal group(GLS≥18%group,n=80)and the impaired group(GLS<18%group,n=70).Some new simplified IR assessment indicators were calculated and compared between the two groups,including body mass index(BMI),TG/HDL-C ratio,triglyceride-glucose(TyG)index,TyG-BMI index,TyG-WHR and metabolic score for IR(METS-IR).Correlation between the GLS and the new simplified IR assessment indexes was analyzed.The receiver operating characteristic(ROC)curve was used to analyze the diagnostic efficacy of different simplified IR assessment indexes,with the area under the curve(AUC)calculated.Furthermore,according to whether the subjects were complicated with hypertension,binary logistics regression analysis was performed to explore the independent correlation between the simplified IR assessment index and GLS<18%.Results Total 150 were included with aged(54.5±13.7)years with 96(64.0%)men and 54(36.0%)women.Compared with the GLS≥18%group,the TG/HDL-C ratio,TyG index,TyG-BMI,and METS-IR of subjects in the GLS<18%group were significantly increased(P<0.05).Pearson correlation analysis showed that TG/HDL-C ratio,TyG index,TyG-BMI,TyG-WHR,and METS-IR were negatively correlated with GLS(P<0.05).ROC analysis showed that TyG index had a certain predictive value for the evaluation of GLS<18%(AUC=0.678,95%CI 0.591-0.765,P<0.001).Stratification based on hypertension and further adjusting for confounding factors,TyG index remains significantly associated with GLS<18%(OR=3.249,95%CI 1.045-10.103,P=0.042).Conclusions The novel simplified insulin resistance evaluation indexes are closely associated with left ventricular subclinical systolic dysfunction in T2DM patients with preserved ejection fraction.TyG index is an effective index to identify left ventricular subclinical dysfunction in these populations.
3.Effects of total saponins of Trillium tschonoskii Maxim on cognitive function and neurovascular unit in 2-VO model rats
Dan YANG ; Li-Jun YANG ; Xian-E TANG ; Gang WANG ; Ren-Ze DUAN ; Xian-Bing CHEN
Medical Journal of Chinese People's Liberation Army 2024;49(3):316-322
Objective To observe the effects of total saponins of Trillium tschonoskii Maxim(TST)on vascular cognitive impairment(VCI),neurovascular units(NVUs),and neural circuit integrity in rats.Methods Forty-eight male Sprague-Dawley(SD)rats were randomly divided into sham-operated group,model group,TST group(intragastric administration,100 mg/kg),and donepezil group(intragastric administration,0.45 mg/kg),and then subjected to ischemic stroke by 2-VO method(bilateral common carotid artery ligation)or sham surgery.After 28 days of intragastric administration,Mirros water maze test was performed to evaluate the spatial learning and memory abilities of rats in each group.HE and Nissl staining were used to observe the pathological changes of brain tissue in rats.The expression of synuclein(SYN)in rat hippocampus was observed by immunohistochemical staining.Changes in dendritic spines in rat's hippocampal neurons were observed by Golgi staining.Western blotting was used to detect the expression levels of IL-1β,IL-10,vascular endothelial growth factor A(VEGFA),postsynaptic density protein 95(PSD95),and growth associated protein 43(GAP43)in rat's hippocampus in each group.Results In Mirros water maze test,rats in model group showed significant prolonged escape latency(P<0.05),and a significant reduction in the number of crossing platforms and the percentage of activity time in the target quadrant(P<0.05)than those in sham-operated group;while rats in TST group and donepezil group showed significant shortened escape latency(P<0.01),and significant increase of the number of times of crossing platforms and the percentage of activity time in the target quadrant(P<0.05)than those in model group.Compared of sham-operated group,model group showed a decrease in the expression of SYN and the number of neurons,Nissl bodies,and dendritic spines in the CA1 region of the hippocampus(P<0.05).Compared with model group,TST group and donepezil group showed an increase in the expression of SYN and the number of neurons,Nissl bodies,and dendritic spines in the CA1 region of the hippocampus(P<0.05).Western blotting showed a significant increase in the expression of IL-1β and VEGF(P<0.05),and a decrease in the expression of IL-10,PSD95,and GAP43(P<0.01)in rat's hippocampus of model group than those in sham-operated group.Compared with model group,TST group and donepezil group showed a significant decrease in the expression of IL-1β(P<0.05),and an increase in the expression of VEGFA,IL-10,and GAP43(P<0.05).Conclusions TST could alleviate cognitive impairment through promoting synaptic plasticity and neurovascular unit remodeling in 2-VO model rats,suggesting its significance as a potential drug for apoplexy.
4.Nanomaterial-based Therapeutics for Biofilm-generated Bacterial Infections
Zhuo-Jun HE ; Yu-Ying CHEN ; Yang ZHOU ; Gui-Qin DAI ; De-Liang LIU ; Meng-De LIU ; Jian-Hui GAO ; Ze CHEN ; Jia-Yu DENG ; Guang-Yan LIANG ; Li WEI ; Peng-Fei ZHAO ; Hong-Zhou LU ; Ming-Bin ZHENG
Progress in Biochemistry and Biophysics 2024;51(7):1604-1617
Bacterial biofilms gave rise to persistent infections and multi-organ failure, thereby posing a serious threat to human health. Biofilms were formed by cross-linking of hydrophobic extracellular polymeric substances (EPS), such as proteins, polysaccharides, and eDNA, which were synthesized by bacteria themselves after adhesion and colonization on biological surfaces. They had the characteristics of dense structure, high adhesiveness and low drug permeability, and had been found in many human organs or tissues, such as the brain, heart, liver, spleen, lungs, kidneys, gastrointestinal tract, and skeleton. By releasing pro-inflammatory bacterial metabolites including endotoxins, exotoxins and interleukin, biofilms stimulated the body’s immune system to secrete inflammatory factors. These factors triggered local inflammation and chronic infections. Those were the key reason for the failure of traditional clinical drug therapy for infectious diseases.In order to cope with the increasingly severe drug-resistant infections, it was urgent to develop new therapeutic strategies for bacterial-biofilm eradication and anti-bacterial infections. Based on the nanoscale structure and biocompatible activity, nanobiomaterials had the advantages of specific targeting, intelligent delivery, high drug loading and low toxicity, which could realize efficient intervention and precise treatment of drug-resistant bacterial biofilms. This paper highlighted multiple strategies of biofilms eradication based on nanobiomaterials. For example, nanobiomaterials combined with EPS degrading enzymes could be used for targeted hydrolysis of bacterial biofilms, and effectively increased the drug enrichment within biofilms. By loading quorum sensing inhibitors, nanotechnology was also an effective strategy for eradicating bacterial biofilms and recovering the infectious symptoms. Nanobiomaterials could intervene the bacterial metabolism and break the bacterial survival homeostasis by blocking the uptake of nutrients. Moreover, energy-driven micro-nano robotics had shown excellent performance in active delivery and biofilm eradication. Micro-nano robots could penetrate physiological barriers by exogenous or endogenous driving modes such as by biological or chemical methods, ultrasound, and magnetic field, and deliver drugs to the infection sites accurately. Achieving this using conventional drugs was difficult. Overall, the paper described the biological properties and drug-resistant molecular mechanisms of bacterial biofilms, and highlighted therapeutic strategies from different perspectives by nanobiomaterials, such as dispersing bacterial mature biofilms, blocking quorum sensing, inhibiting bacterial metabolism, and energy driving penetration. In addition, we presented the key challenges still faced by nanobiomaterials in combating bacterial biofilm infections. Firstly, the dense structure of EPS caused biofilms spatial heterogeneity and metabolic heterogeneity, which created exacting requirements for the design, construction and preparation process of nanobiomaterials. Secondly, biofilm disruption carried the risk of spread and infection the pathogenic bacteria, which might lead to other infections. Finally, we emphasized the role of nanobiomaterials in the development trends and translational prospects in biofilm treatment.
5.Low-dose Radiation Therapy for Osteoarthritis
Guo-Rong MA ; Yong-Ze YANG ; Xin MENG ; Yu-Ting GAO ; Shu-Zhi LI ; Hong-Zhang GUO ; Xiao-Dong JIN
Progress in Biochemistry and Biophysics 2024;51(6):1382-1392
Osteoarthritis (OA) is a chronic degenerative joint disease and the most common type of arthritis. It involves almost any joint and can lead to chronic pain and disability. In the late 19th century, Roentgen discovered X-rays, and then began to use radiotherapy to treat tumors. In the 1980s, Luckey thought that low-level radiation (LDRT) might be beneficial to biology, and it was gradually applied to the treatment of some diseases. This paper introduces the epidemiology, risk factors, clinical manifestations and treatment methods of OA, points out that the cartilage injury and the important effect of synovial inflammation in the pathogenesis of OA, namely when the homeostasis of articular cartilage are destroyed, synthetic metabolism and catabolism imbalances, cartilage cells damaged their breakdown products consumed by synovial cells. Synovial cells and synovial macrophages secrete proinflammatory cytokines, metalloproteinases and proteolytic enzymes, leading to cartilage matrix degradation and chondrocyte damage, which aggravates synovial inflammation and cartilage damage, forming a vicious cycle. The possible mechanism and clinical research progress of LDRT in alleviating OA are discussed. LDRT can regulate inflammatory response, inhibit the production of pro-inflammatory cytokines, and promote the production of anti-inflammatory cytokines, thereby achieving anti-inflammatory effect. Studies have shown that after irradiation, the expression of inducible nitric oxide synthase (iNOS) was decreased, the release of reactive oxygen species (ROS) and the production of superoxide were inhibited, the anti-inflammatory phenotype of macrophages was differentiated from M1 to M2, the inflammatory CD8+ T cells were transformed into CD4+ T cells, and the number of dendritic cells (DC) was significantly reduced. LDRT inhibit the production of proinflammatory factors in leukocytes, reduce their recruitment and adhesion, and down-regulate the expression levels of cell adhesion molecules such as selectin, intercellular adhesion molecule (ICAM) and vascular endothelial cell adhesion molecule (VCAM). LDRT can regulate endothelial cells, stimulate endothelial cells to produce a large amount of TGF-β1, reduce the adhesion of endothelial cells to peripheral blood mononuclear cells (PBMC), and contribute to the anti-inflammatory effect of LDRT. It also exerted anti-inflammatory effects by regulating mitochondrial growth differentiation factor 15 (GDF15). After low-level radiation, the MMP-13 (matrix metalloproteinases-13) and the ADAMTS5 (recombinant a disintegrin and metalloproteinase with thrombospondin-5) decreased, the Col2a1 (collagen type 2) increased in chondrocytes. In the existing clinical studies, most patients can achieve relief of joint pain and recovery of joint mobility after irradiation, and the patients have good feedback on the efficacy. The adverse reactions (acute reactions and carcinogenic risks) caused by LDRT in the treatment of OA are also discussed. During the treatment of OA, a few patients have symptoms such as redness, dryness or itching at the joint skin, and the symptoms are mild and do not require further treatment. Patients are thus able to tolerate more frequent and longer doses of radiotherapy. In general, LDRT itself has the advantages of non-invasive, less adverse reactions, and shows the effect of pain relief and movement improvement in the treatment of OA. Therefore, LDRT has a broad application prospect in the treatment of OA.
6.Antipyretic and anti-inflammatory effects and quality evaluation of a new type of Lonicera Japonicae Flos granule raw decoction piece
Zhi-jun GUO ; Meng-meng HOU ; Dan GAO ; Yu-han WU ; Ze-min YANG ; Jia-lu WANG ; Bo GAO ; Xi-wen LI
Acta Pharmaceutica Sinica 2024;59(7):2087-2097
Traditional decoction pieces have low efficiency, poor batch-to-batch consistency, and irregular physical form, making it difficult to meet the demands of modern automated production and precise and rapid clinical blending. Therefore, this study aims to develop a new type of granular drinking tablet to meet the demand for high-quality development in the traditional Chinese medicine industry. In the current study, the differences and similarities between the new Lonicerae Japonicae Flos (LJF) granular drinking tablets and the traditional ones were evaluated based on the flowability, the paste rate of the standard soup, the characterization fingerprint, the degree of pasting, the content of active ingredients, the transfer rate, and its traditional antipyretic and anti-inflammatory efficacy, using the traditional
7.Bioequivalence study of glipizide tablets in Chinese healthy subjects
Fei-Lang ZHENG ; Lin-Zhong CHENG ; Hai-Ju LI ; Lu YANG ; Ze-Yuan LIU ; Su-Ling WANG
The Chinese Journal of Clinical Pharmacology 2024;40(11):1628-1632
Objective To study the bioequivalence of two glipizide tablets in healthy Chinese subjects.Methods Randomized,open,single-administration,two-period,self-cross-over trial design was used in the study.There were 28 Chinese healthy subjects in the fasted state and 28 in the fed state,complete repeat cross single dose oral glipizide tablets test preparation or reference preparation 5 mg.The plasma concentration of glipizide was determined by liquid chromatography/tandem mass spectrometry at different time points after administration.The non-compartmental model was used to calculate the pharmacokinetic parameters and evaluate the bioequivalence of the two formulations.Results The main pharmacokinetic parameters of glipizide in the fasted state were as follows:Cmax were(551.60±91.26)and(518.10±105.10)ng·mL-1;AUC0-t were(3 074.33±861.91)and(3 026.77±934.25)h·ng·mL-1;AUC0-∞ were(3 204.85±990.78)and(3 166.35±1 107.36)h ng·mL-1.The parameters of glipizide in the fed state were as follows:Cmax were(517.30±98.97)and(472.80±114.48)ng·mL-1;AUC0-t were(3 001.12±830.87)and(2 932.79±736.35)h·ng·mL-1;AUC0-∞ were(3 067.00±918.84)and(2 997.44±819.14)h·ng·mL-1.The 90%confidence interval of the Cmax,AUC0-t and AUC0-∞ of the test formulation and the reference formulation were from 80.00%to 125.00%.The incidence of adverse events in fasted group and fed group was no serious adverse events.Conclusion The two glipizide tablets were bioequivalent under fasted and fed conditions,and good security.
8.Determination of rifapentine concentration in human serum by two-dimensional liquid chromatography
Tao KE ; Tian HE ; Pei-Ze ZHANG ; Wei LI ; Yang ZHOU ; Feng WANG ; Miao-Na LIU
The Chinese Journal of Clinical Pharmacology 2024;40(11):1638-1641
Objective To develop a two-dimensional liquid chromatographic method for rifapentine blood concentration determination.Methods The blood concentration of rifapentine was determined by a novel two-dimensional liquid chromatography(2D-LC)with a one-dimensional column:Aston SC2T(3.5 mm ×50.0 mm,5 μm);a two-dimensional column:Aston SCB(4.6 mm ×250.0 mm,5 μm);the temperature of the column was 40 ℃;the flow rate was 1.0 mL·min-1;the detection wavelength was 335 nm;the injection volume was 300 μL.The specificity,standard curve and lower limit of quantification,precision and recovery,and stability of the method were investigated.The method was used to determine the blood concentration of rifapentine in tuberculosis patients.Results Rifapentine showed good linearity within 0.33-18.62 μg·mL-1 with the standard curve equation of y=2.68 x 105x-5 850.36(r=0.997),the recoveries were 99.81%-105.08%,and the intra-and inter-day precision were ≤4.84%.The results of rifapentine blood concentration measurements in tuberculosis patients were in the range of 0.10-54.70μg·mL-1,and 64.74%were within the therapeutic window concentration range(8-30 μg·mL-1).Conclusion The method is easy to operate,has high sensitivity,low detection limit and high specificity,and is suitable for clinical blood concentration determination.Individual differences in the administration of rifapentine in tuberculosis patients are large,and blood concentration monitoring is required for individualized treatment.
9.Interaction between implants and natural teeth in patients with severe periodontitis:a retrospective study
Ze YANG ; Yu DENG ; Lei MIAO ; Junge LI ; Chen LI ; Yaping PAN
Chinese Journal of Stomatology 2024;59(4):336-343
Objective:To evaluate the clinical outcomes after implant restoration in the posterior region of severe periodontitis patients and to investigate the factors of natural tooth affecting the implant from the perspective of improving natural periodontal health, which may provide a reference for clinical practice.Methods:Fifty-three patients with severe periodontitis who visited the Department of Periodontology at the Affiliated Stomatological Hospital of China Medical University from June 2014 to June 2023 and completed posterior implant treatment with single crown were included, among which were 16 males and 37 females, aged (52.2±8.0) years old, with a total of 136 implants, 135 adjacent natural teeth in the edentulous area. We retrospectively compared the changes of probing depth (PD), bleeding on probing (BOP) and tooth mobility (TM) before and after implant placement. Besides, we explored the effects of the natural periodontal status on PD, BOP and marginal bone loss (MBL) of the implant at the last follow-up examination by univariate analysis and multivariate analysis.Results:Fifty-three patients were followed up for (44.5±14.1) months in average, with longest interval of (8.3±2.7) months. The PD of adjacent natural teeth in the edentulous area improved from 4.3 (3.6, 4.6) mm before implantation to 3.6 (3.2, 4.0) mm in the last review ( P<0.01), while the proportion of BOP (+) improved from 69.6% (94/135) before implantation to 46.7% (63/135) in the last review ( P<0.01). The proportion of teeth with mobility≥Ⅱ decreased from 15.6% (21/135) to 5.9% (8/135) ( P<0.01). The percentage of natural teeth with PD≥4 mm in the same segment improved from 21.0% (13.3%, 26.0%) before implantation to 18.0% (12.0%, 25.0%) in the last review ( P<0.05). The BOP (+)% improved from 29.0% (24.0%, 35.0%) before implantation to 23.0% (18.0%, 31.0%) in the last review ( P<0.05), and the number of teeth with mobility≥Ⅱ decreased from 0.0 (0.0, 1.0) to 0.0 (0.0, 0.8) ( P<0.05). The functional tooth unit score of full natural teeth increased from 8.0 (6.0, 10.0) points before implantation to 12.0 (12.0, 12.0) points in the last review ( P<0.01). PD≥4 mm % increased from 11.0% (6.0%, 25.0%) before implantation to 13.0% (3.0%, 21.0%) in the last review ( P<0.05) and there was no significant differences in BOP (+)% [(17.0±9.7) % vs (14.6±7.2) %, P>0.05]. The number of teeth with mobility≥Ⅱ decreased from 1.0 (0.0, 1.8) to 0.0 (0.0, 0.8) ( P<0.05). Conclusions:Under the premise of regular supportive care, implant restorative treatment in the posterior region of severe periodontitis patients is helpful to improve the PD, BOP and TM of remaining natural teeth. Besides, the stages and grades of periodontitis at initial diagnosis can affect the PD and BOP of implants.
10.Application of MSCT Image Post-Processing Techniques in the Identification of Rib Fracture Malunion
Jing-Chen GE ; Min SHANG ; Ming-Yang YAO ; Ming-Fei WEI ; Jun-Zhan SHI ; Ze-Wei YAO ; Jia-Yin SHI ; Fan LI
Journal of Forensic Medicine 2024;40(4):324-329
Objective To compare the application value of three image post-processing techniques volume rendering(VR),multiplanar reformation(MPR)and curved planar reformation(CPR)in the identifi-cation of rib fracture malunion.Methods The types and numbers of rib fracture malunion in 75 pa-tients were recorded,and the sensitivity,specificity,accuracy and Youden index of VR,MPR and CPR in the diagnosis of rib fracture malunion were compared.Receiver operator characteristic(ROC)curve was drawn and area under the curve(AUC)was calculated,and the detection rates of three image post-processing techniques for different types of rib fracture malunion were compared.Results A total of 243 rib fractures were malunion in 75 patients.The diagnostic sensitivity of VR,MPR and CPR for rib fracture malunion was 52.67%,79.84%and 91.36%,the specificity was 99.58%,97.89%and 99.15%,the accuracy was 83.66%,91.76%and 96.51%,the Youden index was 0.52,0.78 and 0.91,the AUC was 0.761,0.889 and 0.953,respectively.Compared with VR,there were statistically signifi-cant differences in the number of broken rib end misalignment over 1/3,broken rib end overlap,bro-ken rib end angulation and intercostal bridge detected in MPR(P<0.05).Compared with VR,there was a statistically significant difference in the number of different types of rib fracture malunion de-tected by CPR(P<0.05).Compared with MPR,there were statistically significant differences in the number of broken rib end misalignment over 1/3,broken rib end separation and intercostal bridge de-tected in CPR(P<0.05).Conclusion The three image post-processing techniques are of great signifi-cance for the identification of rib fracture malunion.Especially CPR is highly effective in the diagno-sis of rib fracture malunion,and can be used as the main post-processing technique for forensic clini-cal identification of rib fracture malunion.

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