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.

ObjectiveTo explore the effects of Kaixuan Jiedu core prescription （KXJD） on sphingolipid metabolism in the mouse model of imiquimod-induced psoriasis-like skin lesions. MethodsThirty-seven male C57BL/6J mice were randomly assigned into five groups： healthy control （n=11）， model （n=11）， methotrexate （MTX， n=5）， low-dose （15.21 g·kg^-1） KXJD （n=5）， and high-dose （30.42 g·kg^-1） KXJD （n=5）. Psoriasis-like skin lesions were induced in mice with 62.5 mg 5% imiquimod cream applied on the back. The KXJD groups and MTX group were treated with 0.2 mL corresponding decoction and MTX， respectively， by gavage daily， while the other groups were given an equal volume of normal saline by the same way. After 5 days of treatment， back skin lesions were collected. Firstly， healthy control and model mice were selected for tandem mass tag （TMT） quantitative proteomics （control vs model=3 vs 3） and targeted lipid metabolomics （control vs model=11 vs 11）. Then， the binding degree between core components and target proteins was predicted via network pharmacology and molecular docking. Finally， an animal experiment was performed to decipher the specific regulation mechanism of KXJD on sphingolipid metabolism. Immunohistochemistry was employed to determine the expression level of sphingosine-1-phosphate （S1P）， and Western blot was employed to determine the expression levels of sphingosine kinase 2 （SPHK2） and monocyte chemotactic protein-1 （MCP-1）. ResultsTMT proteomics and targeted lipid metabolomics suggested that sphingolipid metabolism was active in the psoriatic skin， and key proteases ［serine palmitoyltransferase， long chain base subunit 2 （SPTLC2）， SPHK2， delta（4）-desaturase sphingolipid 1 （Degs1）， and ceramide synthase 4 （CerS4）］ and 8 sphingolipid metabolites （including ceramides， sphingol， sphingomyelin， and glycosphingolipid） expressed abnormally （P<0.05） compared with those in the healthy skin. The molecular docking results indicated that the binding energy between the active components （quercetin， kaempferol， and luteolin） in KXJD and key proteins involved in sphingolipid metabolism was less than-8 kal·mol^-1. Further experimental verification showed elevated expression levels of SPHK2， S1P， and MCP-1 in psoriatic skin compared with healthy skin （P<0.05）， and KXJD down-regulated the expression levels of SPHK2， S1P， and MCP-1 compared with the model group （P<0.05）. ConclusionThis study indicates that there is an imbalance in sphingolipid metabolism in psoriatic skin lesions. KXJD may reduce psoriasis-like lesions in mice by regulating sphingolipid metabolism via the SPHK2/S1P/MCP-1 pathway.

ObjectiveTo explore the effects of Kaixuan Jiedu core prescription （KXJD） on sphingolipid metabolism in the mouse model of imiquimod-induced psoriasis-like skin lesions. MethodsThirty-seven male C57BL/6J mice were randomly assigned into five groups： healthy control （n=11）， model （n=11）， methotrexate （MTX， n=5）， low-dose （15.21 g·kg^-1） KXJD （n=5）， and high-dose （30.42 g·kg^-1） KXJD （n=5）. Psoriasis-like skin lesions were induced in mice with 62.5 mg 5% imiquimod cream applied on the back. The KXJD groups and MTX group were treated with 0.2 mL corresponding decoction and MTX， respectively， by gavage daily， while the other groups were given an equal volume of normal saline by the same way. After 5 days of treatment， back skin lesions were collected. Firstly， healthy control and model mice were selected for tandem mass tag （TMT） quantitative proteomics （control vs model=3 vs 3） and targeted lipid metabolomics （control vs model=11 vs 11）. Then， the binding degree between core components and target proteins was predicted via network pharmacology and molecular docking. Finally， an animal experiment was performed to decipher the specific regulation mechanism of KXJD on sphingolipid metabolism. Immunohistochemistry was employed to determine the expression level of sphingosine-1-phosphate （S1P）， and Western blot was employed to determine the expression levels of sphingosine kinase 2 （SPHK2） and monocyte chemotactic protein-1 （MCP-1）. ResultsTMT proteomics and targeted lipid metabolomics suggested that sphingolipid metabolism was active in the psoriatic skin， and key proteases ［serine palmitoyltransferase， long chain base subunit 2 （SPTLC2）， SPHK2， delta（4）-desaturase sphingolipid 1 （Degs1）， and ceramide synthase 4 （CerS4）］ and 8 sphingolipid metabolites （including ceramides， sphingol， sphingomyelin， and glycosphingolipid） expressed abnormally （P<0.05） compared with those in the healthy skin. The molecular docking results indicated that the binding energy between the active components （quercetin， kaempferol， and luteolin） in KXJD and key proteins involved in sphingolipid metabolism was less than-8 kal·mol^-1. Further experimental verification showed elevated expression levels of SPHK2， S1P， and MCP-1 in psoriatic skin compared with healthy skin （P<0.05）， and KXJD down-regulated the expression levels of SPHK2， S1P， and MCP-1 compared with the model group （P<0.05）. ConclusionThis study indicates that there is an imbalance in sphingolipid metabolism in psoriatic skin lesions. KXJD may reduce psoriasis-like lesions in mice by regulating sphingolipid metabolism via the SPHK2/S1P/MCP-1 pathway.

Objective This study aims to investigate the effects of transcatheter arterial chemoembolization(TACE)using EqualSpheres,CalliSpheres,and Lipiodol loaded with idarubicin on VX2 liver cancer in rabbits.Methods Twelve New Zealand white rabbits were randomly assigned to three groups:EqualSpheres group,CalliSpheres group,and Lipiodol group(n=4 per group).The VX2 liver cancer animal model was successfully established through ultrasound-guided percutaneous puncture.EqualSpheres,CalliSpheres,and Lipiodol were employed as embolization agents loaded with idarubicin for the embolization procedure.Peripheral blood samples were collected at intervals of 5 minutes,0.5,1,4,12 and 24 hours following embolization and were centrifuged to obtain serum.At 24 hours post-TACE treatment,the rabbits in both the experimental and control groups were euthanized,and both liver cancer tissues and normal liver tissues were collected.UPLC-MS/MS was used to measure the drug concentration of idarubicin in peripheral blood and tissue samples,and Graphpad software was used to construct drug concentration-time curves in peripheral blood.The pharmacokinetic curves were constructed to evaluate the dynamic in vivo distribution characteristics.Results The average drug concentration in the EqualSpheres group(920.06 ng/mL)was significantly higher than that in both the CalliSpheres group(79.47 ng/mL)and the Lipiodol group(118.71 ng/mL).However,the average drug concentration in normal liver tissue of all the three groups was lower,and the difference was not statistically significant.The peripheral blood drug concentration of the three groups decreased at 5 minutes post-TACE and increased over the next 24 hours.The average blood concentration curve of EqualSpheres group increased more steadily compared to the CalliSpheres group and the Lipiodol group.The Cmax of the Lipiodol group was reached at 0.5 hours,measuring 11.54 ng/mL.Both the CalliSpheres group and the EqualSpheres group achieved their Cmax at 5 minutes,with values of 7.82 and 8.36 ng/mL,respectively.Conclusion EqualSpheres loaded with idarubicin achieve a high drug concentration at the tumor site while maintaining a low concentration in peripheral blood over 24 hours.This study demonstrates the stable drug release capability of idarubicin-loaded EqualSpheres.

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 investigate the effects of acute sleep deprivation (ASD) on hippocampal glucose metabolism and neuroinflammation in rat models.Methods:Twenty SD rats (10 males and 10 females) were divided into four groups (five in each group) by random sampling method: female ASD group, male ASD group, female control group, and male control group. Among them, the ASD group constructed the ASD model. After 72h sleep deprivation, all rats underwent 18F-FDG and N, N-diethyl-2-(2-(4-(2- 18F-fluoroethoxy)phenyl)-5, 7-dimethylpyrazolo[1, 5-a]pyrimidin-3-yl)acetamide ( 18F-DPA-714) microPET/CT brain imaging in 2d to compare the changes of 18F-FDG and 18F-DPA-714 SUV mean in the hippocampus of rats. Brain histopathology, immunohistochemistry and immunofluorescence staining were detected in rats. Independent-sample t test was used to analyze the data. Results:18F-FDG imaging showed the hippocampal SUV mean between ASD group and control group (female: 4.11±0.35 vs 1.89±0.28; male: 3.43±0.47 vs 2.02±0.54) were statistically significant ( t values: 9.65, 3.92, P values: <0.001, 0.002). 18F-DPA-714 imaging showed the hippocampal SUV mean between ASD group and control group (females: 0.28±0.01 vs 0.28±0.02; male: 0.26±0.02 vs 0.31±0.04) were not statistically significant ( t values: -0.18, -2.24, P values: 0.859, 0.056). The 18×10 3 translocator protein (TSPO) immunohistochemistry showed the expression in the hippocampal region of the brain between ASD group and control group (female: 0.19±0.02 vs 0.19±0.01; male: 0.21±0.01 vs 0.20±0.01) were not statistically different ( t values: -0.48, -1.67, P values: 0.651, 0.139). Immunofluorescence staining showed that microglial cytosol in the hippocampal region of the brain decreased after 72h of ASD, and the protrusion points and surrounding branches were significantly reduced. Conclusion:Increased hippocampal glucose metabolism in rats is observed after 72 h of ASD without significant neuroinflammation.

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