The initiation of adaptive immune responses relies on the precise recognition and interpretation of antigenic information. In this process, the specific binding of T cell receptors (TCRs) to peptide-major histocompatibility complex (pMHC) molecules represents one of the key molecular events in the initiation of adaptive immune responses. Accordingly, the structural features of TCR-pMHC complexes provide a fundamental basis for dissecting antigen recognition mechanisms and support rational vaccine design, therapeutic target discovery in TCR-based immunotherapy, and TCR identification and optimization. However, experimental determination of TCR-pMHC structures remains costly, time-consuming, and limited in coverage, making computational approaches essential for rapidly obtaining reliable structural information. Computational methods for predicting the structures of TCR-pMHC complexes have advanced rapidly in recent years, driven by progress in deep learning-based modeling frameworks and the increasing availability of structural and sequence resources. Despite these developments, most existing tools do not adequately distinguish the key structural and biophysical differences between MHC class I (MHC-I) and MHC class II (MHC-II) complexes during model construction. As a consequence, their predictive performance differs substantially between class I and class II complexes. In general, structural predictions for class I complexes outperform those for class II complexes. This discrepancy may be related to several fundamental differences between the two systems, including the architecture of the peptide-binding groove, the distribution of peptide lengths, and the properties of peptide flanking residues (PFRs). Compared with MHC-I molecules, MHC-II molecules usually bind longer antigenic peptides, which typically range from 13 to 25 amino acids in length. PFRs at both termini of these peptides participate in regulating the overall conformation of TCR-pMHC class II complexes and exert a pronounced effect on the geometric and physicochemical characteristics of the TCR-pMHC binding interface. Furthermore, within the TCR recognition interface, the complementarity-determining regions (CDRs) consist of segments that differ markedly in conformational behavior. They commonly include regions that are relatively rigid and structurally stable, together with highly flexible segments exhibiting substantial conformational plasticity. These rigidity-flexibility features constitute an essential structural basis enabling TCRs to recognize diverse peptide-MHC ligands and to accommodate conformational heterogeneity at the interface. However, many current modeling tools, in an effort to enforce global conformational stability or reduce structural noise, tend to over-constrain intrinsically flexible regions. Such oversimplification may lead to inappropriate rigidification of flexible CDR loops, resulting in local structural distortions, compromised interface geometry, or even complete modeling failure for specific complexes. Against this background, the review approaches the field from the perspective of computational differences between MHC-I and MHC-II complexes. We first systematically organize and summarize available resources related to TCRs and pMHCs, including structural datasets, sequence databases, prediction tools, and benchmarking studies. We then focus on five representative tools capable of predicting both class I and class II complexes—AlphaFold2, AlphaFold3, TCRmodel2, tFold-TCR, and TCR-pHLA_ModellerS. After excluding structures present in the training sets of these tools, we constructed a benchmark dataset comprising 25 class I and 10 class II TCR-pMHC complexes in the bound state and conducted a systematic evaluation using this dataset. We first employ widely used general evaluation metrics, including All-Atom Root Mean Square Deviation (All-Atom RMSD), Backbone RMSD, Template Modeling score (TM-score), and DockQ, to assess the global conformational accuracy and interface modeling quality of class I and class II complexes. For class II complexes, we propose for the first time a peptide flanking residue deviation index, including the PFRs-Deviation Index (PFRs-DI), N-PFR-Deviation Index (N-PFR-DI), and C-PFR-Deviation Index (C-PFR-DI), to quantitatively characterize conformational deviations in PFRs. In addition, we propose the CDR conformational consistency index (CCC) designed to qualitatively evaluate the ability of prediction tools to capture TCR CDR conformational flexibility. These metrics collectively assess a tool’s ability to model both overall conformation and critical functional regions, thereby addressing the limitations of existing evaluation criteria that overemphasize global structure while inadequately capturing modeling quality in key functional areas. This establishes a unified analytical framework for MHC-I and MHC-II complexes to guide data resource selection, modeling strategy formulation, and evaluation system development. The framework further advances computational modeling and provides crucial support for multi-scale analysis of TCR-pMHC recognition mechanisms and their biological functions.

The initiation of adaptive immune responses relies on the precise recognition and interpretation of antigenic information. In this process, the specific binding of T cell receptors (TCRs) to peptide-major histocompatibility complex (pMHC) molecules represents one of the key molecular events in the initiation of adaptive immune responses. Accordingly, the structural features of TCR-pMHC complexes provide a fundamental basis for dissecting antigen recognition mechanisms and support rational vaccine design, therapeutic target discovery in TCR-based immunotherapy, and TCR identification and optimization. However, experimental determination of TCR-pMHC structures remains costly, time-consuming, and limited in coverage, making computational approaches essential for rapidly obtaining reliable structural information. Computational methods for predicting the structures of TCR-pMHC complexes have advanced rapidly in recent years, driven by progress in deep learning-based modeling frameworks and the increasing availability of structural and sequence resources. Despite these developments, most existing tools do not adequately distinguish the key structural and biophysical differences between MHC class I (MHC-I) and MHC class II (MHC-II) complexes during model construction. As a consequence, their predictive performance differs substantially between class I and class II complexes. In general, structural predictions for class I complexes outperform those for class II complexes. This discrepancy may be related to several fundamental differences between the two systems, including the architecture of the peptide-binding groove, the distribution of peptide lengths, and the properties of peptide flanking residues (PFRs). Compared with MHC-I molecules, MHC-II molecules usually bind longer antigenic peptides, which typically range from 13 to 25 amino acids in length. PFRs at both termini of these peptides participate in regulating the overall conformation of TCR-pMHC class II complexes and exert a pronounced effect on the geometric and physicochemical characteristics of the TCR-pMHC binding interface. Furthermore, within the TCR recognition interface, the complementarity-determining regions (CDRs) consist of segments that differ markedly in conformational behavior. They commonly include regions that are relatively rigid and structurally stable, together with highly flexible segments exhibiting substantial conformational plasticity. These rigidity-flexibility features constitute an essential structural basis enabling TCRs to recognize diverse peptide-MHC ligands and to accommodate conformational heterogeneity at the interface. However, many current modeling tools, in an effort to enforce global conformational stability or reduce structural noise, tend to over-constrain intrinsically flexible regions. Such oversimplification may lead to inappropriate rigidification of flexible CDR loops, resulting in local structural distortions, compromised interface geometry, or even complete modeling failure for specific complexes. Against this background, the review approaches the field from the perspective of computational differences between MHC-I and MHC-II complexes. We first systematically organize and summarize available resources related to TCRs and pMHCs, including structural datasets, sequence databases, prediction tools, and benchmarking studies. We then focus on five representative tools capable of predicting both class I and class II complexes—AlphaFold2, AlphaFold3, TCRmodel2, tFold-TCR, and TCR-pHLA_ModellerS. After excluding structures present in the training sets of these tools, we constructed a benchmark dataset comprising 25 class I and 10 class II TCR-pMHC complexes in the bound state and conducted a systematic evaluation using this dataset. We first employ widely used general evaluation metrics, including All-Atom Root Mean Square Deviation (All-Atom RMSD), Backbone RMSD, Template Modeling score (TM-score), and DockQ, to assess the global conformational accuracy and interface modeling quality of class I and class II complexes. For class II complexes, we propose for the first time a peptide flanking residue deviation index, including the PFRs-Deviation Index (PFRs-DI), N-PFR-Deviation Index (N-PFR-DI), and C-PFR-Deviation Index (C-PFR-DI), to quantitatively characterize conformational deviations in PFRs. In addition, we propose the CDR conformational consistency index (CCC) designed to qualitatively evaluate the ability of prediction tools to capture TCR CDR conformational flexibility. These metrics collectively assess a tool’s ability to model both overall conformation and critical functional regions, thereby addressing the limitations of existing evaluation criteria that overemphasize global structure while inadequately capturing modeling quality in key functional areas. This establishes a unified analytical framework for MHC-I and MHC-II complexes to guide data resource selection, modeling strategy formulation, and evaluation system development. The framework further advances computational modeling and provides crucial support for multi-scale analysis of TCR-pMHC recognition mechanisms and their biological functions.

ObjectiveTo systematically compare the effects of diverse electromagnetic stimulation protocols on hand function and activities of daily living (ADL) in stroke patients using network meta-analysis (NMA), and screen the optimal stimulation strategy for post-stroke hand dysfunction rehabilitation. MethodsNMA was performed in accordance with the PRISMA-NMA statement. Databases of CNKI, Wanfang data, VIP, CBM, PubMed, Web of Science and Embase were searched from database inception to April, 2026 for eligible randomized controlled trials (RCTs) comparing different electromagnetic stimulation protocols for post-stroke hand impairment. The Cochrane Risk of Bias tool and PEDro scale were used to assess methodological quality of included studies, while the GRADE system was adopted to grade evidence quality of primary outcomes of Fugl-Meyer Assessment-Upper Extremities (FMA-UE) and modified Barthel Index (MBI). After literature screening, data extraction and bias evaluation, RevMan 5.4 and Stata 17.0 were used for meta-analysis and NMA. ResultsA total of 22 RCT involving 17 electromagnetic stimulation protocols were finally included. The PEDro scores ranged from six to ten. The top five protocols for improving FMA-UE score were repetitive peripheral magnetic stimulation (rPMS) + repetitive transcranial magnetic stimulation (rTMS), intermittent theta-burst stimulation (iTBS) + rPMS, iTBS + transcranial direct current stimulation (tDCS), transcutaneous electrical acupoint stimulation (TEAS) and contralaterally controlled functional electrical stimulation (CCFES). tDCS was the most effective on MBI, followed by TEAS and iTBS+rPMS. Evidence quality for FMA-UE and MBI was moderate. Funnel plots suggested low risk of publication bias, and consistency tests verified good coherence between direct and indirect comparisons in network models. ConclusionElectromagnetic stimulation significantly facilitates upper limb and hand functional recovery, and improves ADL in stroke patients. The combined central-peripheral magnetic stimulation protocol may be the most effective on motor rehabilitation, whereas tDCS on ADL.

The sterile electrode acupuncture needle for single use is an innovative product that combines traditional acupuncture with modern electronic technology, and it has obtained Class Ⅱ medical device registration certificate. This acupuncture device consists of a needle body and a handle. The diameter of the needle body ranges from 0.16 mm to 0.55 mm, and the length from 7 mm to 150 mm. The spiral spray technology is adopted to modify the micron-level insulating coat on stainless steel needle body. The needle holder is connected to the electroacupuncture device (conductive), the micro-film insulated needle body (non-conductive) and the membrane-free needle tip (conductive) can provide a precise electrical stimulation for different tissue layers of acupoints (such as deep nerves and fascia). The intradermal stimulation test, cytotoxicity test and hypersensitivity reaction test have showed a favorable biocompatibility, laying a solid and reliable safety for clinical application. This acupuncture device is suitable for the in-depth invasive stimulation at the sites of human body surface in combination with electroacupuncture equipment in medical institutions.
Humans ; Needles ; Acupuncture Therapy/instrumentation* ; Electrodes ; Equipment Design ; Electroacupuncture/instrumentation* ; Acupuncture Points ; Animals

Recently, male reproductive health has attracted extensive attention, with the adverse effects of circadian disruption on male fertility gradually gaining recognition. However, the mechanism by which circadian disruption leads to damage to male reproductive system remains unclear. In this review, we first summarized the dual regulatory roles of circadian clock genes on the male reproductive system: (1) circadian regulation of testosterone synthesis via the hypothalamic-pituitary-testicular (HPT) and hypothalamic-pituitary-adrenal (HPA) axes; (2) non-circadian regulation of spermatogenesis. Next, we further listed the possible mechanisms by which circadian disruption impairs male fertility, including interference with the oscillatory function of the reproductive system, i.e., synchronization of the HPT axis, crosstalk between the HPT axis and the HPA axis, as well as direct damage to germ cells by disturbing the non-oscillatory function of the reproductive system. Future research using spatiotemporal omics, epigenomic assays, and neural circuit mapping in studying the male reproductive system may provide new clues to systematically unravel the mechanisms by which circadian disruption affects male reproductive system through circadian clock genes.
Male ; Humans ; Animals ; Circadian Clocks/physiology* ; Hypothalamo-Hypophyseal System/physiology* ; Circadian Rhythm/genetics* ; Spermatogenesis/physiology* ; Pituitary-Adrenal System/physiology* ; Testis/physiology* ; Testosterone/biosynthesis* ; CLOCK Proteins ; Infertility, Male/physiopathology*

(±)-Talapyrones A-F (1-6), six pairs of dimeric polyketide enantiomers featuring unusual 6/6/6 and 6/6/6/5 ring systems, were isolated from the fungus Talaromyces adpressus. Their structures were determined by spectroscopic analysis and HR-ESI-MS data, and their absolute configurations were elucidated using a modified Mosher's method and electronic circular dichroism (ECD) calculations. (±)-Talapyrones A-F (1-6) possess a 6/6/6 tricyclic skeleton, presumably formed through a Michael addition reaction between one molecule of α-pyrone derivative and one molecule of C₈ poly-β-keto chain. In addition, compounds 2/3 and 4/5 are two pairs of C-18 epimers, respectively. Putative biosynthetic pathways of 1-6 were discussed.
Polyketides/isolation & purification* ; Talaromyces/chemistry* ; Stereoisomerism ; Molecular Structure ; Circular Dichroism ; Pyrones/chemistry*

Objective To analyze the risk factors,traditional Chinese medicine(TCM)syndromes,and pathogen distribution in patients with bronchiectasis(BE)complicated with type 2 diabetes mellitus(T2DM).Methods From June 2022 to June 2024,a total of 299 patients with acute exacerbation of BE admitted to Guangdong Integrated Chinese and Western Medicine Hospital Affiliated to Guangzhou University of Chinese Medicine were selected.Based on the presence of T2DM,the patients were divided into the BE-T2DM group(74 cases)and the BE-only group(225 cases).Clinical data of the patients were collected,and univariate analysis and multivariate logistic regression models were used to identify risk factors for BE complicated with T2DM.TCM syndromes and pathogen distribution were statistically analyzed.Results(1)Univariate analysis showed that there were statistically significant differences between the two groups in gender,age,body mass index(BMI),hypertension,coronary atherosclerotic heart disease(shortened to coronary heart disease),atherosclerosis,the ratio of forced expiratory volume in one second to forced vital capacity(FEV1/FVC),white blood cell count(WBC),neutrophil count analysis for the risk factors showed that gender,BMI,hypertension,and FEV1/FVC were the independent risk factors for BE complicated with T2DM.(2)In terms of the distribution of TCM syndromes,both groups were mainly characterized by phlegm-heat accumulating in the lung syndrome and phlegm-damp obstructing the lung syndrome,and BE-T2DM group had a higher proportion of phlegm-heat accumulating in the lung syndrome.(3)For the infection of pathogens,BE-T2DM group had a higher infection rate of Haemophilus influenzae,Acinetobacter baumannii,and Klebsiella pneumoniae,while the BE-only group was predominantly infected with Pseudomonas aeruginosa;BE-T2DM group had a significantly higher rate of viral infections,mainly infected with influenza A virus,rhinovirus,and SARS-CoV-2;BE-T2DM group also suffered from fungal infections,usually infected with Candida albicans.Conclusion For BE patients complicated with T2DM,the independent risk factors are gender,BMI,hypertension,and FEV1/FVC;the common TCM syndromes are phlegm-heat accumulating in the lung and phlegm-damp obstructing the lung;pathogen infections are mainly caused by Gram-negative bacteria,viruses,and fungi.

AIM To study the chemical constituents from the sticks and leaves of Croton cascarilloides Raeusch.and their biological activities.METHODS The 95％ethanol extract from the sticks and leaves of C.cascarilloides was isolated and purified by MCI,silica gel,Sephadex LH-20 and semi-preparative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.LPS-induced NO RAW264.7 cell model induced by LPS was used to evaluate its anti-inflammatory activity in vitro.GES-1 injury model induced by taurocholic acid was used to screen the gastric mucosal protection activity.RESULTS Fourteen compounds were isolated and identified as bullatantriol(1),(-)-boscialin(2),(+)-dehydrovomifoliol(3),3-(hydroxylacetyl)-indole(4),pinoresinol(5),3,7-dimethyl-octa-1,7-diene-3,6-ol(6),(+)-syringaresinol(7),curcasinlignan B(8),cleomiscosin C(9),cleomiscosinD(10),2,6-dimethyl-octa-1,7-dien-3,6-diol(11),vanillin(12),vanillic acid(13),methyl vanillate(14).Compound 4 had certain anti-inflammatory activity,with IC50 values of 73.62 μmol/L.The protective rates of 25 μmol/L compounds 1-4,6,9-12 and 14 on gastric mucosal epithelial cells were 30.07％,34.18％,23.91％,30.92％,17.51％,19.69％,31.76％,22.46％,30.56％and 14.49％,respectively.CONCLUSION Compounds 1-14 are isolated from this plant for the first time.Compound 4 shows anti-inflammatory activity,1-4,6,9-12 and 14 show different degrees of gastric mucosal epithelial cell protective activity.

Acute lateral ankle sprain (ALAS) is one of the most common sport injuries, with high incidence, recurrence and disability rates. Currently, exercise rehabilitation-based non-surgical treatment is the primary management approach for ALAS. However, there remain improper practices such as excessive immobilization or uncontrolled activity, which contribute to recurrent sprains and chronic ankle instability, significantly impairing patients′ athletic function and quality of life. To standardize the non-surgical management of ALAS, improve the cure rates, and reduce the recurrence and disability rates, Chinese Sports Rehabilitation Medicine Training Project of Chinese Medical Association, Foot and Ankle Basics and Orthopedics Group, Orthopedic Branch of Chinese Medical Doctor Association, and Sports Medicine Branch of Jiangsu Medical Association organized relevant experts to formulate Expert consensus on non-surgical treatment for acute lateral ankle sprain ( version 2025), following the principles of scientific vigor, practicality, and innovation. Thirteen recommendations were proposed for standardized treatment protocols across different healing phases, aiming to provide references for standard management of ALAS and improve the therapeutic outcomes.

Objective:To evaluate the predictive role of ultrasound, genetic testing, and clinical features in the malignancy risk of Bethesda Ⅲ thyroid nodules, and to explore strategies for optimizing treatment decisions.Methods:This retrospective study included 227 Bethesda Ⅲ thyroid nodules from patients who underwent surgical treatment at the Thyroid Surgery Department of Nanjing Drum Tower Hospital between Jan. 2020 and Dec. 2023. All patients underwent ultrasound evaluation and fine-needle aspiration. For nodules diagnosed as ultrasound, genetic testing, and clinical features were analyzed using univariate and multivariate regression to assess their association with malignancy.Results:Among the 227 nodules, 214 were malignant, resulting in a malignancy rate of 94.2%. The malignancy rate of thyroid nodules was 94.2%. In univariate analysis, age ( P=0.016), BRAF V600E gene mutation ( P<0.001), nodule size ( P=0.002), and TIRADS ( P<0.001) were significantly associated with malignancy in Bethesda Ⅲ thyroid nodules. Multivariate analysis confirmed that age ( OR=0.939, P=0.049) and BRAF V600E gene mutation ( OR=24.641, P<0.001) were significantly associated with thyroid nodule nature and served as independent predictive factors for malignancy. Conclusions:Genetic testing is an important method for predicting the malignancy of Bethesda Ⅲ thyroid nodules, and ultrasound also has high clinical value in assessing the malignancy risk of nodules. While some clinical features are highly correlated with nodule characteristics, they may not be practical in clinical application. For nodules classified as TIRADS 3 through ultrasound evaluation and negative for BRAF mutations, continued observation may be considered, whereas TIRADS 5 nodules or nodules with BRAF mutations should be prioritized for surgical treatment.