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.

As a distinctive resource of Chinese civilization， traditional Chinese medicine （TCM） technology transfer faces significant opportunities under the background of digital and intelligent transformation， while also being constrained by unique challenges such as the complexity of its theoretical system， lengthy industrial chains， and multidimensional policy restrictions， resulting in a "high-value-high-threshold" paradox. At present， TCM technology transfer is deeply trapped in a "threefold reluctance" dilemma， i.e.， unwillingness to transfer， inability to transfer， and lack of capacity to transfer. Specifically， the disconnection between scientific research evaluation systems and market demand leads to low conversion rates of research achievements， unclear ownership and compliance risks suppress innovation incentives， and the absence of professional services intensifies supply-demand mismatches. This article systematically analyzes the specific characteristics of TCM technology transfer and proposes a breakthrough pathway centered on full-chain digital and intelligent transformation. By integrating technologies such as intelligent sorting systems， blockchain-based traceability， and AI diagnostic models， the TCM ecosystem spanning "cultivation-production-service" can be reconstructed. In terms of standardization， promoting the progression from "experience-based data conversion" to "data standardization" and further to "intelligent standardization" is advocated to resolve quality control challenges. For example， a "three-no-one-full" certification system can strengthen quality trust. Policy coordination should focus on optimizing mechanisms for the transformation of scientific and technological achievements， while exploring intellectual property securitization and risk-sharing models to stimulate research momentum. In terms of internationalization， reliance on the Belt and Road Initiative platform to promote the export of geo-authentic medicinal material brands and standards is recommended to build a dual-driven model of "technology plus culture". Looking ahead， through the construction of national-level databases， the cultivation of interdisciplinary talent， and the mutual recognition of international standards， a new paradigm of "scientific intelligent manufacturing" can be formed， providing systematic solutions for the modernization of TCM and global health governance.

This study investigated the infection status,drug resistance,and molecular characteristics of Shiga toxin-producing Escherichia coli(STEC)in domestic goats in Chengkou county,Chongqing.In August 2023,283 fecal samples were collected from households in Chengkou county.After enrichment with EC broth and inoculation onto selective media,samples that tested positive for stx1/stx2 were selected for further isolation.The positive strains were investigated with antimicrobial susceptibility testing and whole genome sequencing.According to the whole genomic sequences,the stx subtypes,serotypes,multi-locus sequence types,virulence genes,drug resistance genes,and phylogenetic relationships of the STEC strains were analyzed.Forty-six strains of STEC were isolated from 283 goat fecal samples,thus resulting in a detection rate of 16.25%.The 46 STEC strains were categorized into 12 O∶H serotypes,among which O76∶H19 and O8∶H7 predominated,each represented by 9 strains.Five STEC strains were identified as serotype O157∶H7.The 46 STEC strains were categorized into 11 sequence types(STs),among which ST675 and ST196 predominated,each represented by nine strains,accounting for a 19.57%proportion.The strains were categorized into 7 stx subtypes,among which stx1c(26/46,56.52%),followed by stx2k(9/46,19.57%)predominated.All nine Stx2k-STEC strains were identified as serotype O8∶H7 and sequence type ST196.In antimicrobial susceptibility testing,2 STEC strains were resistant to ampicillin,one strain was resistant to ampicillin/sulbactam,one strain was resistant to cefazolin,and one strain was resistant to cefoxitin.Nine Stx2k-STEC strains were found to carry the beta-lactam resistance gene blaEC-18.Antimicrobial sensitivity tests revealed that the nine Stx2k-STEC strains were sensitive to all 15 tested antibiotics.Moreover,phylogenetic analysis indicated that the 9 Stx2k-STEC strains were remarkably similar but showed high genetic diversity with respect to that of the Stx2k-STEC strains isolated from other regions in China.Goatsare an important animal reservoir for STEC in theChengkou district of Chongqing,and novel sequence type Stx2k-STEC strains distinct from those found in other regions of China were identified in this region.

Aim To investigate the role of RNF8 in the proliferation,invasion and migration of hepatocellular carcinoma and in the promotion of epithelial-mesenchy-mal transition(EMT);to clarify the regulatory mecha-nism of RNF8 on hepatocellular carcinoma cells.Methods Immunohistochemistry was used to detect the expression of RNF8 and RhoA in human hepatocel-lular carcinoma tissues and adjacent tissues;Western blot and RT-PCR were used to detect the expression levels of RNF8 and RhoA in human normal hepatocytes and hepatocellular carcinoma cells.RNF8 was overex-pressed in HepG2 cells,and siRNA interference was used to downregulate the expression of RNF8.The cell experimental groups were as follows:control group(Control,normal HepG2 cells),RNF8 overexpression group,RNF8 low expression group(siRNA RNF8),RNF8 overexpression+Rhosin(20 μmol·L-1,RhoA blocker)group.The cell proliferation ability was detected by CCK-8 method;the cell migration ability was detected by scratch test;the cell invasion ability was detected by Transwell test;finally,the expression levels of RNF8,RhoA,PCNA,CyclinD1,N-cadherin,vimentin,Slug,and E-cadherin proteins and mRNA were detected by Western blot and RT-PCR.Results The expression of RNF8 and RhoA in liver cancer tissues and liver cancer cells significantly increased;after RNF8 knockdown,the proliferation,migration,in-vasion and EMT of liver cancer cells were significantly inhibited,while overexpression of RNF8 significantly increased the proliferation,migration,invasion ability of liver cancer cells and promoted EMT.RhoA showed a positive correlation with knockdown and overexpression of RNF8.When RNF8 was overexpressed and RhoA blocker was given at the same time,the phenomenon of overexpression of RNF8 increasing the proliferation,mi-gration,invasion ability and promoting EMT of liver cancer cells was significantly reversed.Conclusions RNF8 can promote the proliferation,migration,invasion and EMT of liver cancer cells,and at the same time promote the expression of RhoA.RNF8 promotes the progression of hepatocellular carcinoma by regulating RhoA to promote EMT.

Aim To investigate the therapeutic effect of newly formulated Tadalafil tablets on liver fibrosis in mice induced by carbon tetrachloride(CCl4)and its impact on the activation of hepatic stellate cells(HSCs).Methods Liver fibrosis model was estab-lished by intraperitoneally injecting 20％CCl4 corn oil solution twice a week for eight weeks.After four weeks of modeling,the treatment group was administered ei-ther the newly formulated Tadalafil tablets(1.0 mg·kg-1)or the Cialis(2.5 mg·kg-1)via gavage for the remaining four weeks.We assessed the effects of Tadalafil on collagen deposition,tissue structural dam-age,and HSCs activation markers in the fibrotic liver of mice using serum biochemical analysis,histopathologi-cal staining,and Western blotting following the treat-ment period.LX-2 cells were cultured and treated with tadalafil after TGF β1 stimulation,and the effects of tadalafil on LX-2 cell activation were assessed via Western blot.Results Compared to the normal mice,the model group mice exhibited a significantly higher liver-specific index,increased liver function indicators,and notable hepatocyte necrosis.Additionally,liver lobules were damaged,accompanied by severe infiltra-tion of inflammatory cells.Both smooth muscle actin(α-SMA)and fibronectin(Fn)were elevated,serving as markers of HSCs activation.As a result of treatment with the newly formulated Tadalafil tablets,liver tissue damage was significantly reduced,transaminase levels decreased,necrosis and inflammatory cell infiltration were reduced,and collagen fiber deposition was allevia-ted,and α-SMA and Fn expression was reduced.It was worth noting that low-dose newly formulated Tadalafil tablets were found to be as effective as high-dose Cia-lis.In a cellular model,Tadalafil significantly inhibited the activation of LX-2 cells and reduced the expression of proteins related to cell activation.Conclusions The newly formulated Tadalafil tablets can significantly inhibit HSCs activation,reduce extracellular matrix(ECM)deposition,improve liver fibrosis and liver function damage caused by CCl4.This new formulation offers a significant advantage over Cialis in terms of ef-fectiveness,with a lower effective dose.

Objective:To explore the safety and short-term efficacy of single-port robotic transanal total mesorectal excision (SPr-taTME).Methods:The retrospective and descriptive study was conducted. The clinicopathological data of six patients who underwent SPr-taTME at Daping Hospital of Army Medical University from October to November 2024 were collected. There were 3 males and 3 females, aged (65±5)years. Observation indicators: (1) intraoperative situations; (2) postoperative situations; (3) follow-up. Measurement data with normal distribution were represen-ted as Mean± SD, measurement data with skewed distribution were represented as M(range). Count data were described as absolute numbers. Results:(1) Intraoperative situations. All patients successfully underwent SPr-taTME without conversion to laparotomy or blood transfusion. There was no intraoperative complication such as accidental hemorrhage or adjacent organ injury. No intra-operative adverse events or mortality occurred. The operation time of the 6 patients was 286(range, 240?400)minutes. The time of transanal platform setup and robotic docking was (21±10)minutes, transanal dissection time was (97±45)minutes, and transabdominal dissection time was (90±35)minutes. The volume of intraoperative blood loss was (47±14)mL. Among the six patients, 1 case underwent synchronous transanal and transabdominal surgery, while 5 cases underwent non-synchronous procedures. Specimens were extracted transanally in 5 cases and via an auxiliary abdominal incision in 1 case. The single-port robotic platform was utilized for the abdominal surgery in 3 cases, while laparoscopy was used in 3 cases. Splenic flexure mobilization was performed in 3 cases and omitted in the other 3 cases. Three patients underwent hand-sewn sigmoid colon-anal anastomosis, 1 case underwent modified Bacon pull-through anastomosis, 1 case received stapled sigmoidorectal anastomosis, 1 case underwent sigmoid colostomy without anastomosis due to significant bowel edema. Two cases didn′t undergo intestinal stoma, 2 cases underwent virtual ileostomy, 1 case underwent ileostomy, and 1 case underwent sigmoid colostomy. (2) Postoperative situations. All patients started water drinking and out‐of‐bed activities on postoperative day 1 and liquid diet intake on postoperative day 2. The time to postoperative first flatus was 1(range, 1?3)days, and duration of postoperative hospital stay was (8±2)days.The total number of lymph nodes dissected was 13±2, with the number of positive lymph nodes as 0(range, 0?3) and the distance of distal resection margin as (23±8)mm. Pathological examination of 6 patients showed 1 case in stage T1N0, 2 cases in stage ypT0N0, 1 case in ypT1N0, 1 case in ypT3N1, and 1 case in ypT0N1. The degree of mesorectal integrity was complete in 5 patients and nearly complete in 1 patient. The surgical specimens of 6 patients showed negative in distal, proximal and circumferential margin. (3) Follow-up. All 6 patients completed the 30-day postoperative follow-up. None of the patients experienced postoperative complication such as bleeding, intestinal obstruction or anastomotic leakage. There was no readmission within 30 days after surgery. Digital rectal examination or colonoscopy on postoperative 30 day confirmed no anastomosis-related complications, including stenosis, dehiscence or anastomotic leakage. All 6 patients survived.Conclusion:The SPr-taTME is safe and feasible, with satisfactory short-term efficacy.

Objective:We summarize the clinical characteristics of surgeries in which the thyroid lobe is used as a transfer flap to treat early pharyngeal fistula following total laryngectomy.We also provide useful data for improving the diagnosis and management of this condition.Methods:Retrospective analysis was conducted on data from 8 patients with pharyngocutaneous fistulas after total laryngectomy for laryn-geal and pharyngeal cancer patients admitted to Hunan Provincial People's Hospital(The First Hospital Affiliated to Hunan Normal University)between October 2016 and October 2023.The surgeons performed a double-layer repair technique that included local inversion and a purse-string suture of the fistula using the thyroid lobe as a transfer flap.Clinical data were collected to analyze postoperative outcomes.Results:All eight patients experienced successful pharyngeal fistula repair.Postoperatively,these patients were managed with nasogastric tube feed-ing,liquid diet,and prophylactic antibiotics to prevent infection.After 10 days,their diet was changed to oral liquids,and their nasogastric tubes were removed.All patients were discharged after complete recovery.Conclusions:Use of the thyroid lobe as a transfer flap in a double-layer repair technique involving local inversion of the fistula is an effective method for repairing early pharyngeal fistula after total laryngectomy.This approach offers several advantages,including ease of flap harvesting,shortened operation time,reduced patient discom-fort,high transfer flap survival rate,and rapid postoperative recovery.The clinical efficacy of this technique is well-supported,making it a re-liable option for the management of early pharyngeal leaks.

AIM To study the chemical constituents from Commelina communis L.METHODS The 95％ethanol extract from C.Communis was isolated and purified by activated charcoal,silica gel,Sephadex LH-20,and HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.RESULTS Seventeen compounds were isolated and identified as p-hydroxyl ethyl cinnamate(1),p-hydroxybenzaldehyde(2),vanillin(3),4-hydroxy-2,3-dimethyl-2-nonen-4-olide(4),hemeratrol A(5),chakyunglupulin B(6),chakyunglupulin A(7),2-(2-hydroxyethyl)-3-methylfumaric acid(8),N-cis-feruloyl tyramine(9),N-trans-coumaroyltyramine(10),5,6,7,3',4',5'-hexamethoxyflavone(11),N-trans-sinapoyltyramine(12),dihydro-feruloyltyramine(13),N-trans-feruloyltyramine(14),2-phenylethanol-β-D-glucoside(15),quercetin-3-O-β-D-glucoside(16),and isorhamnetin-3-O-β-D-glucopyranoside(17).CONCLUSION Compounds 4-8,10 and 11 are isolated from Commelina genus for the first time,and 1,9,12-15 are first isolated from this plant.

Aim To explore the mechanism of Lycium barbarum glycopeptide(LbGP)improving aging in rat primary ovarian granulosa cells.Methods This study divided the cells into a normal group,a DOX group,and four different LbGP concentration treatment groups post-DOX intervention.Results Cell proliferation was assessed using CCK-8,EDU,and Ki67 assays,while aging markers and mitochondrial function-related fac-tors were detected using immunofluorescence and West-ern blotting.The results showed that,compared to the DOX group,LbGP treatment significantly increased cell viability(P＜0.05)and promoted proliferation(P＜0.05).Post LbGP treatment,the β-galactosidase-posi-tive area in cells was significantly reduced compared to the DOX group(P＜0.05).Immunofluorescence re-sults indicated that,compared to the DOX group,levels of p21 and γH2AX significantly decreased(P＜0.05),while pRB increased(P＜0.05)after LbGP treatment.Western blot results showed that,compared to the DOX group,the aging phenotype proteins p21 and p53 significantly decreased(P＜0.05),and pRB notably increased(P＜0.05)in the LbGP treatment group.The release of cytC into the cytoplasm and the activated caspase-9 significantly decreased(P＜0.05);levels of CAMKK2,pAMPK,and mitochondrial calcium homeostasis regulator MCU increased(P＜0.05);nuclear energy metabolism-related proteins SirT1,PGC1α/β and ATP5A1 significantly increased(P＜0.05);compared to the DOX group,ROS levels significantly decreased after LbGP treatment(P＜0.05).Conclusions The results suggest that LbGP can ameliorate DOX-induced aging in rat primary ovar-ian granulosa cells,potentially through the upregulation of the CAMKKβ/AMPK signaling pathway,thereby im-proving mitochondrial calcium homeostasis and increas-ing the expression levels of cell energy metabolism-re-lated regulatory proteins.This provides an experimen-tal basis for LbGP's potential role in supporting the im-provement of ovarian function.