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.

This paper aimed to explore the effects of Duzhong Decoction(DZD)-containing serum on the proliferation and osteoblast differentiation of MC3T3-E1 cells through L-type voltage-gated calcium channels(L-VGCCs). L-VGCCs inhibitors, nifedipine and verapamil, were used to block L-VGCCs in osteoblasts. MC3T3-E1 cells were divided into a control group, a low-dose DZD-containing serum(L-DZD) group, a medium-dose DZD-containing serum(M-DZD) group, a high-dose DZD-containing serum(H-DZD) group, a nifedipine group, a H-DZD + nifedipine group, verapamil group, and a H-DZD + verapamil group. The CCK-8 method was used for cell proliferation analysis, alkaline phosphatase(ALP) assay kits for intracellular ALP activity measurement, Western blot for protein expression level in cells, real-time fluorescence quantitative PCR technology for intracellular mRNA expression level determination, fluorescence spectrophotometer for free Ca~(2+) concentration determination in osteoblasts, and alizarin red staining(ARS) for mineralized nodule formation in osteoblasts. The experimental results show that compared to the control group, DZD groups can promote MC3T3-E1 cell proliferation, ALP activity, and mineralized nodule formation, increase intracellular Ca~(2+) concentrations, and upregulate the protein expression of bone morphogenetic protein 2(BMP2), collagen Ⅰ(COL1), α2 subunit protein of L-VGCCs(L-VGCCα2), and the mRNA expression of Runt-related transcription factor 2(RUNX2), and BMP2. After blocking L-VGCCs with nifedipine and verapamil, the intervention effects of DZD-containing serum were inhibited to varying degrees. Both nifedipine and verapamil could inhibit ALP activity, reduce mineralized nodule areas, and downregulate the expression of bone formation-related proteins. Moreover, the effects of DZD-containing serum on increasing MC3T3-E1 cell proliferation, osteoblast differentiation, and Ca~(2+) concentrations, upregulating the mRNA expression of osteoprotegerin(OPG) and protein expression of phosphorylated protein kinase B(p-Akt) and phosphorylated forkhead box protein O1(p-FOXO1), and upregulating phosphatase and tensin homolog(PTEN) expression were reversed by nifedipine. The results indicate that DZD-containing serum can increase the Ca~(2+) concentration in MC3T3-E1 cells to promote bone formation, which may be mediated by L-VGCCs and the PTEN/Akt/FoxO1 signaling pathway, providing a new perspective on the mechanism of DZD in treating osteoporosis.
Animals ; Osteoblasts/metabolism* ; Cell Proliferation/drug effects* ; Cell Differentiation/drug effects* ; Mice ; Drugs, Chinese Herbal/pharmacology* ; Calcium Channels, L-Type/genetics* ; Alkaline Phosphatase/genetics* ; Serum/chemistry* ; Cell Line ; Osteogenesis/drug effects* ; Bone Morphogenetic Protein 2/genetics*

The patient is a 63-year-old man with a history of chronic illness, presenting with intermittent low-grade fever, recurrent dry cough, and shortness of breath upon exertion. Lung CT showed a nodule in the left lung and a large mass in the right lung with liquefactive necrosis and an air-fluid level accompanied by pleural effusion. Laboratory findings showed significantly increasedf immunoglobulin G (IgG), IgG4, and total immunoglobulin E, along with a mild increase in eosinophils, and moderate elevations in erythrocyte sedimentation rate and high-sensitivity C-reactive protein. Malignant tumors, immunological, and hematological diseases were ruled out. Various antibiotic treatments were ineffective and the condition was recurrent. Conventional methods failed to identify the pathogen. Metagenomic next-generation sequencing (mNGS) technology was used to detect Mycobacterium monacense from lung tissue. Targeted antibiotic treatment was effective with no further episodes of low-grade fever and alleviation of dry cough symptoms. This case underscores the clinical significance of mNGS technology for the diagnosis and treatment of unexplained pulmonary infections, providing a useful reference for clinical diagnostic and treatment.

Objective To investigate the effect of dorsal repulsive axon guidance protein(Draxin)on the migration of trunk neural crest cells during the early development of embryonic mouse spinal cord.Methods Immunohistochemistry and in situ hybridization were used to detect the expression characteristics of Draxin in early embryonic spinal cord(8 mice each group);In situ hybridization was used to detect the change of migration characteristics of trunk neural crest cells in early embryonic spinal cord of different types of mouse(5 mice each group);in vitro culture method was used to check the effect of Draxin on the migration characteristics of embryonic mouse trunk neural crest cells(16 mice each group).Resultsβ-galactosidase gene Z(LacZ)gene was introduced when Draxin gene was knocked out to produce Draxin gene knockout mice.β-galactosidase staining was used to detect LacZ gene expression in Draxin knockout embryonic mice,and the result showed that Draxin expression was observed in the spinal cord of early embryonic mice since 9.5 days(E9.5).Draxin expression was obvious in the embryonic mice spinal cord in E10.5 period.In situ hybridization was used to detect the expression of Draxin gene in the spinal cord of wild type embryonic mice,and the result further verified the obvious expression of Draxin in the early embryonic mice spinal cord in El0.5 period.Sox10 in situ hybridization was used to detect neural crest cell migration in the spinal cord of embryonic mice in E10.5 period.The result showed that segmental migration of neural crest cells in the early embryonic spinal cord of some Draxin knockout mice was delayed compared with the wild type mice.The effect of Draxin on the migration of wild type early embryonic mice trunk neural crest cells in vitro was tested.The result showed that Draxin reduced the migration distance of neural crest cells in vitro.Conclusion In the early developmental stage of embryonic spinal cord(E9.5-E10.5),neural crest cells migrated exuberant.At the same time,Draxin plays an important inhibitory function in the formation of the specific migration pathways of trunk neural crest cells by promoting neural crest cells migrating away from Draxin expressing regions.

To investigate the association between obesity-related metabolic indices and the risk of knee osteoarthritis(KOA) in middle-aged and older Chinese adults(≥45 years) using data from the China Health and Retirement Longitudinal Study(CHARLS).

Objective To investigate the efficacy of an interpretable integrated learning model combining clinical indicators,CT image features and radiomics features for the differential diagnosis of lung squamous cell carcinoma and adenocarcinoma,so as to provide references for clincal treatment decisions.Methods A retrospective analysis was conducted on clinical and imaging data from 220 patients(231 lesions)with primary non-small cell lung cancer at Jiangjin Central Hospital of Chongqing(Center 1)and 83 patients(84 lesions)at Chongqing General Hospital(Center 2).In Center 1,the squamous cell carcinoma group consisted of 60 patients(60 lesions),while the adenocarcinoma group included 160 patients(171 lesions).In Center 2,the squamous cell carcinoma group comprised 18 patients(18 lesions),and the adenocarcinoma group involved 65 patients(66 lesions).The patients were categorized into squamous cell carcinoma and adenocarcinoma groups based on pathological findings.Center 1 was randomly partitioned into a training set and a validation set at a 7∶3 ratio,while Center 2 served as the independent test set.Firstly,a deep learning model,VB-Net,was used to automatically segment the tumor region on the lung window image;secondly,the SMOTE(synthetic minority oversampling technique)method was used to balance the categories in the training set and standardize the extracted features with Z-scores;thirdly,the least absolute shrinkage and selection operator(LASSO)were used to select the optimal radiomics features and calculate the radiomics score(Radscore),and univariate and multivariate logistic regression was used to screen clinical indicators and independent clinical factors for differentiating lung squamous cell carcinoma and adenocarcinoma in CT image features;finally,three ensemble learning algorithms(AdaBoost,Bagging decision tree and XGBoost)were used to combine independent clinical factors and Radscore to construct the model.The receiver operating characteristic(ROC)curve was used to evaluate the diagnostic performance of the models.SHAP technique was used to analyze the feature contribution and model decision-making process.Results Among the evaluated ensemble models,AdaBoost and Bagging decision trees demonstrated overfitting tendencies.In contrast,the XGBoost model showed the best performance,achieving AUC values of 0.939,0.887 and 0.853 in the training,validation and independent test sets,respectively.SHAP indicated that Radscore was the most important feature affecting the performance of the model.The decision diagram enabled the visualization of the diagnostic process of the model.Conclusion The interpretable integrated learning model based on clinical indicators,CT image and radiomics features is expected to non-invasively diagnose lung squamous cell carcinoma and adenocarcinoma before treatment and assist clinicians make treatment decisions as early as possible.[Chinese Medical Equipment Journal,2025,46(7):12-20]

Aim To investigate the therapeutic effects of cinnamaldehyde on synovial lesions in mice with knee osteoarthritis(KOA)and its regulatory mecha-nism in the phagocytic function of synovial macropha-ges.Methods In the animal experiments,mouse ser-um and synovial tissue were extracted.HE staining was used to evaluate the inflammatory cell infiltration in the synovial tissue.ELISA was employed to detect the lev-els of inflammatory factors such as interleukins in the serum.Western blot was used to detect the expression of Ras homolog family member A(RhoA),Rho-associ-ated protein kinase 1(ROCK1),myosin light chain(MLC),and p-MLC proteins in the synovial tissue.RT-qPCR was utilized to detect the expression of in-flammatory factors and pathway-related mRNA in the synovial tissue.TUNEL staining was used to detect ap-optosis in the synovial tissue.In the cellular experi-ments,after the intervention,RAW267.4 cells were subjected to Western blot and RT-qPCR for the detec-tion of the aforementioned indicators,and confocal mi-croscopy was used to assess phagocytic function.Re-sults After cinnamaldehyde intervention,the synovial inflammatory infiltration was significantly reduced,the protein and mRNA expression of the RhoA/ROCK1/MLC signaling pathway was markedly downregulated,the fluorescence intensity of TUNEL staining signifi-cantly decreased,and the phagocytic function of macro-phages was enhanced.Conclusion Cinnamaldehyde can inhibit RhoA/Rock1/MLC signaling pathway,en-hance macrophage burial,improve synovial inflamma-tion,and delay the progression of KO A mice.

Objective:To document any effect of repeated high-frequency repetitive transcranial magnetic stimulation (rTMS) using double-cone coils on the lower limb motor function of stroke survivors.Methods:A total of 40 stroke survivors were randomly divided into an rTMS group and a sham stimulation group, each of 20. The rTMS group received rTMS at 10Hz with a double-cone coil, while a coil that produced sound but no magnetic stimulation was used with the sham group. The treatments were administered daily, five times a week, for three weeks. Before as well as after 1, 2 and 3 weeks of treatment, lower limb motor function, balance, and the root mean square (RMS) and median frequency (MF) of the rectus femoris and tibialis anterior muscles were evaluated using the Fugl-Meyer lower extremity assessment (FMA-LE), the Berg Balance Scale (BBS), the Modified Barthel Index (MBI), Brunnstrom staging, the TecnoBody balance assessment system, and surface electromyography.Results:Compared with the sham stimulation group, the BBS score of the rTMS group was significantly higher after 2 weeks of treatment, and both the FMA-LE and BBS scores were significantly higher after 3 weeks. The average Brunnstrom stage in the sham group had increased significantly after 3 weeks, but in the rTMS group it had increased after 2 weeks. By 3 weeks there were no significant differences between the two groups. In terms of movement control, the average motion ellipse area in the rTMS group was significantly smaller than among the sham group after 2 weeks, and after 3 weeks the average motion trajectory length was significantly shorter than in the sham group. The average RMS of the rectus femoris in the rTMS group was significantly higher than the sham group′s average after 3 weeks of treatment, indicating improved muscle activation.Conclusions:High-frequency rTMS using a conical coil can effectively improve the lower limb motor function and balance ability of stroke survivors, demonstrating promising clinical application potential.

Objective To explore the feasibility and corresponding implementation methods of constructing a sample resource bank based on individual-level data of completed clinical trials and using it to construct external controls for drug/device clinical trials.Methods Taking the pre-marketing clinical trial of transcatheter active valve replacement(TAVR)for the treatment of aortic valve stenosis as an example,the individual-level databases of multiple trials were standardized to form a sample bank.The original data of any trial in the sample bank were selected as the experimental group,and the remaining samples were selected as the control group.The potential confounding was handled by using the propensity score matching and stratification methods to clarify the process of constructing external controls based on the sample bank of individual-level data of clinical trials.Results This study included individual-level data of single-group trials of 4 TAVR devices,with a total of 569 subjects(59.2%male).The number of subjects in Trials 1 to 4 was 120,120,163,and 166,respectively.Propensity score matching enabled the matching of 113,117,125,and 147 subjects with comparable or similar characteristics from individual-level data from other trials,respectively,demonstrating a high matching success rate.The PS score distribution plot after stratification showed that the proportions of subjects in the experimental and control groups in strata 1 to 5 in scheme 1 were 4/103,11/103,22/92,32/87,and 51/64,respectively.For all constructed external controlled trials,a certain number of control samples with similar baseline characteristics to the experimental groups were distributed within each propensity score stratum.The results of the simulation test also reflected the potential differences between different devices in the 12-month all-cause mortality rate.Conclusions The sample bank constructed with individual-level data from clinical trials,as a high-quality data source,can serve as a source of external control for single-arm trials in the same field,and as a useful supplement to the external control scenario of real-world evidence to support drug and device development.At the same time,targeted research on research methods and bias control measures in related fields is also needed.

Aim To investigate the therapeutic effects of cinnamaldehyde on synovial lesions in mice with knee osteoarthritis(KOA)and its regulatory mecha-nism in the phagocytic function of synovial macropha-ges.Methods In the animal experiments,mouse ser-um and synovial tissue were extracted.HE staining was used to evaluate the inflammatory cell infiltration in the synovial tissue.ELISA was employed to detect the lev-els of inflammatory factors such as interleukins in the serum.Western blot was used to detect the expression of Ras homolog family member A(RhoA),Rho-associ-ated protein kinase 1(ROCK1),myosin light chain(MLC),and p-MLC proteins in the synovial tissue.RT-qPCR was utilized to detect the expression of in-flammatory factors and pathway-related mRNA in the synovial tissue.TUNEL staining was used to detect ap-optosis in the synovial tissue.In the cellular experi-ments,after the intervention,RAW267.4 cells were subjected to Western blot and RT-qPCR for the detec-tion of the aforementioned indicators,and confocal mi-croscopy was used to assess phagocytic function.Re-sults After cinnamaldehyde intervention,the synovial inflammatory infiltration was significantly reduced,the protein and mRNA expression of the RhoA/ROCK1/MLC signaling pathway was markedly downregulated,the fluorescence intensity of TUNEL staining signifi-cantly decreased,and the phagocytic function of macro-phages was enhanced.Conclusion Cinnamaldehyde can inhibit RhoA/Rock1/MLC signaling pathway,en-hance macrophage burial,improve synovial inflamma-tion,and delay the progression of KO A mice.