ObjectiveProtein-protein interactions (PPIs) are fundamental to the execution of biological functions within living cells. However, traditional biochemical methods, such as co-immunoprecipitation (Co-IP), often fail to capture transient, weak, or membrane-associated interactions due to the stringent detergent requirements for cell lysis. Proximity labeling (PL) has emerged in recent years as a transformative technology for mapping the proteomes of specific subcellular compartments and identifying dynamic interactomes in situ. Golgi protein 73 (GP73, also known as GOLPH2), a resident type II Golgi transmembrane protein, is a well-recognized clinical biomarker for liver diseases, including hepatocellular carcinoma (HCC). Despite its clinical significance, the comprehensive physiological and pathological functions of GP73 remain partially understood. This study aims to establish an APEX2-mediated proximity labeling system specifically targeting GP73 to map its interactome in a living cellular environment, thereby providing new insights into its molecular roles and regulatory mechanisms. MethodsTo achieve spatial specificity, we first constructed a stable cell line expressing a fusion protein consisting of GP73 and the engineered soybean peroxidase APEX2. The localization of the GP73-APEX2 fusion protein was validated to ensure it correctly targeted the Golgi apparatus. The proximity labeling reaction was initiated by incubating the cells with biotin-phenol (BP) for 30 min, followed by a brief (1 min) treatment with1 mmol/L hydrogen peroxide (H₂O₂). This catalytic reaction converts BP into highly reactive, short-lived biotin-phenoxyl radicals that covalently attach to endogenous proteins within a small labeling radius of the GP73-APEX2 enzyme. Subsequently, the cells were quenched, and biotinylated proteins were enriched using high-affinity streptavidin-coated magnetic beads. The captured “neighbor” proteins were subjected to on-bead digestion and analyzed via liquid chromatography-tandem mass spectrometry (LC-MS/MS) for high-throughput identification. Rigorous bioinformatics analysis, including Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and protein-protein interaction network mapping, was performed to interpret the biological significance of the identified candidates. ResultsOur results demonstrate the successful establishment of a robust and sensitive APEX2-based proximity labeling system for GP73. We identified a total of 95 high-confidence interacting proteins that were significantly enriched in the GP73 proximity proteome compared to control groups. Bioinformatics analysis revealed that these interactors were predominantly associated with biological processes such as vesicular transport, protein localization, and, most notably, molecular functions related to “ribosome binding” and “translation regulation”. This suggested an unexpected role for the Golgi-resident GP73 in the cellular translation machinery. To validate these findings, we performed targeted biochemical assays which confirmed a direct interaction between GP73 and the subunits of the eukaryotic translation initiation factor 3 (eIF3) complex, specifically EIF3G and EIF3I. Furthermore, functional validation using the surface sensing of translation (SUnSET) assay—a non-radioactive method to monitor protein synthesis—revealed that the overexpression of GP73 significantly promoted global protein translation levels in the cell, whereas its depletion or inhibition resulted in reduced translation efficiency. ConclusionThis study successfully utilized APEX2-mediated proximity labeling to provide the first systematic map of GP73 interactome in living cells. Our findings uncover a novel, unconventional function of GP73 as a regulator of cellular protein translation, likely mediated through its interaction with the eIF3 complex. This discovery significantly broadens our understanding of the biological roles of GP73 beyond its traditional function in the Golgi apparatus and suggests that it may act as a bridge between Golgi-related trafficking and the protein synthesis machinery. Furthermore, the technical framework established in this study provides a valuable template for investigating other complex organelle-associated protein networks and resolving transient macromolecular interactions in various physiological and pathological contexts.

Objective To develop a deep learning model based on fundus retinal images to improve the detection rate of mild cognitive impairment(MCI)in patients with coronary heart disease,achieve early intervention and improve prognosis.Methods The study was a single-center cross-sectional study that retrospectively included patients diagnosed with coronary heart disease(CHD)by coronary angiography(≥50％ stenosis of at least one coronary vessel)from Beijing Anzhen Hospital between November 2021 and December 2022.The whole data set was randomly divided into the training set and the testing set according to the ratio of 8∶2 for model development.After that,the patient data of the same center from January 2023 to April 2023 were included in the time verification method to verify the model.The diagnostic criteria for MCI were MMSE＜27 or MoCA＜26.Four kinds of convolutional neural network(CNN)architectures were used to train fundus images,and a comprehensive vision model of MCI detection was established through model integration.The area under the curve(AUC),sensitivity and specificity of the receiver operating curve(ROC)were used to evaluate the performance of the AI model.Results We collected 5 880 eligible fundus images from 3 368 CHD patients.Based on the results of the MMSE scale,the algorithm was labeled,including 2 898 males and 527 MCI patients.The AUC of the deep learning model in the test group is 0.733(95％CI 0.688-0.778),and the sensitivity of the algorithm in the test group is 0.577(95％CI 0.528-0.625)by using the operating point with the maximum sum of sensitivity and specificity.With a specificity of 0.758(95％CI 0.714-0.802),corresponding to a validated AUC of 0.710(95％CI 0.601-0.818).Based on the results of the MoCA scale,the algorithm labels 2 437 males and 1 626 MCI patients.The AUC of the deep learning model in the test group was 0.702(95％CI 0.671-0.733).The operating point with the maximum sum of sensitivity and specificity was selected,and the sensitivity of the algorithm was 0.749(95％CI 0.719-0.778)and the specificity was 0.561(95％CI 0.527-0.595),corresponding to the AUC value of the verification group was 0.674(95％CI 0.622-0.726).Conclusions The deep learning algorithm model based on fundus images has good diagnostic performance,and may be used as a new non-invasive,convenient and rapid screening method for MCI in CHD population.

Objective:To investigate the value of gadoxetate disodium-enhanced MRI combined with T 1 mapping in preoperative prediction of cytokeratin 19 (CK19) and glypican-3 (GPC3) positive dual-phenotype hepatocellular carcinoma (DPHCC). Methods:This case-control study included retrospectively enrolled patients with pathologically confirmed HCC from Central People′s Hospital of Zhanjiang (training set, n=85; December 2020 to July 2022) and the Second Affiliated Hospital, School of Medicine, South China University of Technology (test set, n=35; April 2023 to April 2024). Patients were categorized into CK19 and GPC3 positive DPHCC group (training set=19, test set=11) and non-DPHCC group (training set=66, test set=24) based on postoperative immunohistochemical staining. All patients received preoperative MRI scans, including gadoxetate disodium-enhanced imaging and T 1 mapping. Clinical data were collected, qualitative MRI features were evaluated, and quantitative parameters were measured, including signal intensity, T 1 values, apparent diffusion coefficient (ADC), tumor-to-liver ADC ratio (rADC), tumor-to-liver signal intensity ratio, and T 1 relaxation time reduction rate (ΔT 1%). Statistical comparisons between groups were performed using independent t-tests, Mann-Whitney U tests, or χ2 tests. Multivariate logistic regression identified independent predictors of CK19 and GPC3 positive DPHCC, and a combined model was constructed. Predictive performance was evaluated using area under the receiver operating characteristic curve (AUC), with DeLong test comparing model performance. Results:Significant intergroup differences were observed in alpha-fetoprotein (AFP), total bilirubin, direct bilirubin, DWI target sign, rADC, hepatobiliary-phase T 1 (T 1HBP), and ΔT 1% ( P<0.05). Multivariate analysis identified AFP>20 ng/ml ( OR=5.835, 95% CI 1.019-33.397, P=0.048), DWI target sign ( OR=13.408, 95% CI 2.216-81.131, P=0.005), and ΔT1%≤31% ( OR=14.429, 95% CI 2.166-96.125, P=0.006) as independent predictors of DPHCC. The AUC values of the aforementioned three independent predictors and the combined model for predicting DPHCC were 0.641 (95% CI 0.530-0.742), 0.679 (95% CI 0.569-0.777), 0.740 (95% CI 0.634-0.829), and 0.886 (95% CI 0.799-0.945) in the training set, and 0.568 (95% CI 0.390-0.743), 0.669 (95% CI 0.490-0.818), 0.689 (95% CI 0.511-0.843), and 0.824 (95% CI 0.658-0.931) in the test set, respectively. The DeLong test results showed that in the training set, the diagnostic performance of the combined model was superior to those of the three individual features ( Z=3.68, P<0.001; Z=3.15, P=0.002; Z=3.15, P=0.002). In the test cohort, the combined model demonstrated better diagnostic performance than AFP>20 ng/ml and ΔT 1%≤31% ( Z=2.15, P=0.032; Z=2.12, P=0.034), while no statistically significant difference was observed compared with the DWI target sign ( Z=1.77, P=0.076). Conclusion:The integrated model incorporating clinical data, gadoxetate disodium-enhanced MRI, and T 1 mapping parameters effectively predicts CK19 and GPC3 positive DPHCC.

AIM:To investigate the role of SET and MYND domain-containing protein 3(SMYD3)-mediated histone H3 lysine 4 trimethylation(H3K4me3)dysregulation in pulmonary vascular remodeling in a rat model of pulmo-nary arterial hypertension associated with atrial septal defect(PAH-ASD).METHODS:The PAH-ASD rat model was created using transseptal puncture and radiofrequency ablation techniques.The rats were randomly assigned to 5 groups:normal,sham,PAH-ASD,PAH-ASD+vehicle(Veh),and PAH-ASD+BCI-121(SMYD3 inhibitor).Four weeks after modeling,lung tissues and pulmonary vessels were harvested for subsequent analysis.Western blot analysis was conducted to evaluate the protein levels of SMYD3,H3K4me3,transforming growth faction-β1(TGF-β1),and collagen type Ⅲ(Col Ⅲ).The mRNA expression of TGF-β1 was quantified using RT-qPCR.Histological assessment of pulmonary vascu-lar fibrosis,vascular wall thickness and smooth muscle proliferation was executed through Masson's trichrome and HE staining.Co-immunoprecipitation(Co-IP)assay was performed to investigate the interactions among SMYD3,H3K4me3,and TGF-β1.Hemodynamic parameters,including mean pulmonary artery pressure(mPAP),were quantified using a computerized physiological signal acquisition system.RESULTS:The Western blot analysis indicated a significant in-crease in the protein levels of SMYD3,TGF-β1,Col Ⅲ,and H3K4me3 in the PAH-ASD group compared with the sham group(P<0.05).RT-qPCR corroborated the elevation of TGF-β1 mRNA expression in the PAH-ASD group(P<0.05).Furthermore,Masson's trichrome and HE staining techniques revealed more pronounced pulmonary vascular fibrosis,an augmented vascular wall area,and an elevated vascular area index within the PAH-ASD group(P<0.05).Additionally,the right ventricular hypertrophy index(RVHI)and mPAP were significantly elevated in the PAH-ASD group(P<0.05).The administration of BCI-121 resulted in a significant reduction of SMYD3,TGF-β1,Col Ⅲ,and H3K4me3 levels(P<0.05),while also mitigating pulmonary vascular fibrosis,RVHI,mPAP,pulmonary vascular area,and area index(P<0.05).Co-IP confirmed direct interactions among SMYD3,H3K4me3,and TGF-β1.CONCLUSION:Histone methyl-transferase SMYD3-mediated histone H3K4me3 modification plays a role in the pulmonary vascular remodeling of PAH-ASD model rats.The underlying mechanism may involve the regulation of pulmonary vascular proliferation and fibrosis me-diated by the overexpression of TGF-β1 and Col Ⅲ.

Radiation prevention and treatment drugs are a rapidly developing field.Radiation prevention and treatment drugs can be roughly divided into four categories:chemical synthetic drugs,biological products,natural plant extracts and traditional Chinese medicine compounds,which are widely used in medical,scientific research and other fields.This paper reviews the classification of radiation prevention and treatment drugs,which can be roughly divided into four categories:chemical synthetic drugs,biological products,natural plant extracts and traditional Chinese medicine compounds.At the same time,its mechanism of action and clinical application are elaborated in detail,and the risk assessment is carried out from the aspects of effectiveness,safety and drug interaction.Finally,the risk reduction strategies are summarized from the aspects of clinical medication specification and monitoring,continuous drug safety research,improvement of emergency reserve and support capacity and construction of full-cycle regulatory system,so as to provide reference for the rational application and further research of radiation prevention and treatment drugs.

Objective:To investigate the value of gadoxetate disodium-enhanced MRI combined with T 1 mapping in preoperative prediction of cytokeratin 19 (CK19) and glypican-3 (GPC3) positive dual-phenotype hepatocellular carcinoma (DPHCC). Methods:This case-control study included retrospectively enrolled patients with pathologically confirmed HCC from Central People′s Hospital of Zhanjiang (training set, n=85; December 2020 to July 2022) and the Second Affiliated Hospital, School of Medicine, South China University of Technology (test set, n=35; April 2023 to April 2024). Patients were categorized into CK19 and GPC3 positive DPHCC group (training set=19, test set=11) and non-DPHCC group (training set=66, test set=24) based on postoperative immunohistochemical staining. All patients received preoperative MRI scans, including gadoxetate disodium-enhanced imaging and T 1 mapping. Clinical data were collected, qualitative MRI features were evaluated, and quantitative parameters were measured, including signal intensity, T 1 values, apparent diffusion coefficient (ADC), tumor-to-liver ADC ratio (rADC), tumor-to-liver signal intensity ratio, and T 1 relaxation time reduction rate (ΔT 1%). Statistical comparisons between groups were performed using independent t-tests, Mann-Whitney U tests, or χ2 tests. Multivariate logistic regression identified independent predictors of CK19 and GPC3 positive DPHCC, and a combined model was constructed. Predictive performance was evaluated using area under the receiver operating characteristic curve (AUC), with DeLong test comparing model performance. Results:Significant intergroup differences were observed in alpha-fetoprotein (AFP), total bilirubin, direct bilirubin, DWI target sign, rADC, hepatobiliary-phase T 1 (T 1HBP), and ΔT 1% ( P<0.05). Multivariate analysis identified AFP>20 ng/ml ( OR=5.835, 95% CI 1.019-33.397, P=0.048), DWI target sign ( OR=13.408, 95% CI 2.216-81.131, P=0.005), and ΔT1%≤31% ( OR=14.429, 95% CI 2.166-96.125, P=0.006) as independent predictors of DPHCC. The AUC values of the aforementioned three independent predictors and the combined model for predicting DPHCC were 0.641 (95% CI 0.530-0.742), 0.679 (95% CI 0.569-0.777), 0.740 (95% CI 0.634-0.829), and 0.886 (95% CI 0.799-0.945) in the training set, and 0.568 (95% CI 0.390-0.743), 0.669 (95% CI 0.490-0.818), 0.689 (95% CI 0.511-0.843), and 0.824 (95% CI 0.658-0.931) in the test set, respectively. The DeLong test results showed that in the training set, the diagnostic performance of the combined model was superior to those of the three individual features ( Z=3.68, P<0.001; Z=3.15, P=0.002; Z=3.15, P=0.002). In the test cohort, the combined model demonstrated better diagnostic performance than AFP>20 ng/ml and ΔT 1%≤31% ( Z=2.15, P=0.032; Z=2.12, P=0.034), while no statistically significant difference was observed compared with the DWI target sign ( Z=1.77, P=0.076). Conclusion:The integrated model incorporating clinical data, gadoxetate disodium-enhanced MRI, and T 1 mapping parameters effectively predicts CK19 and GPC3 positive DPHCC.

Objective To improve the diagnosis and treatment of Streptococcus liver abscesses by analyzing the clinical presentations,antibiotic susceptibility,and treatment strategies of patients.Methods A retrospective analysis was conducted on 21 patients diagnosed with liver abscess caused by Streptococcus from June 2012 to June 2022.The data included demographic information,clinical characteristics,laboratory tests,imaging findings,treatment strategies,and outcomes.Results The 21 patients were 29 to 77 years of age,and 81.0％were male.Clinical manifestations included fever,chills,fatigue,and abdominal pain.Some patients also had headache and altered consciousness,indicating possible concomitant brain abscess.Hematogenous dissemination and biliary tract origin were the most common routes of infection.The predominant pathogen was Streptococcus anginosus group(76.2％).Single pathogen infection was found in 12 cases and mixed infection in 9 cases.All isolates were sensitive to penicillin,cefotaxime,vancomycin,and levofloxacin,but 36.4％(4/11)of the isolates showed resistance to erythromycin and clindamycin.Four patients developed metastatic abscesses,and two experienced septic shock.The main treatment approach was a combination of antibiotics and percutaneous liver puncture drainage,resulting in improvement in 18 patients.Conclusions Liver abscesses caused by Streptococcus are usually non-specific in terms of symptoms.Streptococcus anginosus group is the primary pathogen.Antibiotics combined with percutaneous drainage is an effective treatment approach.It is crucial for clinicians to be aware of potential brain abscesses and the necessity of early intervention.

Objective To explore the application value of MRI diaphragmatic navigation technology combined with three dimensional liver acquisition with volume acceleration-flexible(3D LAVA-FLEX)sequence in abdominal enhanced imaging of infants and young children.Methods A retrospective analysis was conducted on imaging data of 84 infants and young children who underwent abdominal enhanced MRI examination in our hospital between January 2021 and December 2023.All 84 infants and young children initially underwent conventional dynamic contrast-enhanced 3D LAVA-FLEX sequence scanning;the delayed phase images obtained were included in the dynamic enhancement group.Subsequently,diaphragmatic navigation combined with 3D LAVA-FLEX sequence examination was implemented,and the obtained images were included in the diaphragm navigation group.Subjective scoring was performed for images in both groups,while the signal to noise ratio(SNR),contrast to noise ratio(CNR),and artifact quantification(AQ)were measured and compared between the two groups.Results The respiratory motion artifacts,the clarity of liver parenchyma enhancement,the clarity of liver vascular enhancement,the clarity of spleen parenchyma enhancement and the overall image quality score in the diaphragm navigation group were higher than those in the dynamic enhancement group,and the differences were statistically significant(P<0.05).There were statistically significant differences in SNR and AQ between the two groups of images(P<0.000 1),while there was no statistically significant difference in CNR between the two groups of images(P>0.05).Conclusion Diaphragmatic navigation technology combined with 3D LAVA-FLEX sequence imaging can improve the image quality of abdominal MRI enhanced imaging in infants and young children,and provide a reference for clinical diagnosis and treatment.

AIM:To investigate the role of SET and MYND domain-containing protein 3(SMYD3)-mediated histone H3 lysine 4 trimethylation(H3K4me3)dysregulation in pulmonary vascular remodeling in a rat model of pulmo-nary arterial hypertension associated with atrial septal defect(PAH-ASD).METHODS:The PAH-ASD rat model was created using transseptal puncture and radiofrequency ablation techniques.The rats were randomly assigned to 5 groups:normal,sham,PAH-ASD,PAH-ASD+vehicle(Veh),and PAH-ASD+BCI-121(SMYD3 inhibitor).Four weeks after modeling,lung tissues and pulmonary vessels were harvested for subsequent analysis.Western blot analysis was conducted to evaluate the protein levels of SMYD3,H3K4me3,transforming growth faction-β1(TGF-β1),and collagen type Ⅲ(Col Ⅲ).The mRNA expression of TGF-β1 was quantified using RT-qPCR.Histological assessment of pulmonary vascu-lar fibrosis,vascular wall thickness and smooth muscle proliferation was executed through Masson's trichrome and HE staining.Co-immunoprecipitation(Co-IP)assay was performed to investigate the interactions among SMYD3,H3K4me3,and TGF-β1.Hemodynamic parameters,including mean pulmonary artery pressure(mPAP),were quantified using a computerized physiological signal acquisition system.RESULTS:The Western blot analysis indicated a significant in-crease in the protein levels of SMYD3,TGF-β1,Col Ⅲ,and H3K4me3 in the PAH-ASD group compared with the sham group(P<0.05).RT-qPCR corroborated the elevation of TGF-β1 mRNA expression in the PAH-ASD group(P<0.05).Furthermore,Masson's trichrome and HE staining techniques revealed more pronounced pulmonary vascular fibrosis,an augmented vascular wall area,and an elevated vascular area index within the PAH-ASD group(P<0.05).Additionally,the right ventricular hypertrophy index(RVHI)and mPAP were significantly elevated in the PAH-ASD group(P<0.05).The administration of BCI-121 resulted in a significant reduction of SMYD3,TGF-β1,Col Ⅲ,and H3K4me3 levels(P<0.05),while also mitigating pulmonary vascular fibrosis,RVHI,mPAP,pulmonary vascular area,and area index(P<0.05).Co-IP confirmed direct interactions among SMYD3,H3K4me3,and TGF-β1.CONCLUSION:Histone methyl-transferase SMYD3-mediated histone H3K4me3 modification plays a role in the pulmonary vascular remodeling of PAH-ASD model rats.The underlying mechanism may involve the regulation of pulmonary vascular proliferation and fibrosis me-diated by the overexpression of TGF-β1 and Col Ⅲ.

Lung cancer poses a serious threat to global public health security.Chemotherapy,as the main strategy for cancer treatment,faces challenges such as high toxicity and drug resistance.Anticancer peptides have the potential of being developed into new anticancer drugs due to their advantages of broad-spectrum anticancer activity,rapid action,and difficulty in generating drug resistance,but they also face shortcomings such as weak activity and strong toxic side effects.The weakly acidic microenvironment of tumors(pH 6.5-6.8)provides a good idea for the design of anticancer peptides of high-efficiency and low-toxicity.Previously,we designed the acid-sensitive antibacterial peptide pHly-1 using the wolf spider(Lycosa singoriensis)toxin Lycosin-Ⅰ as a template.In this study,we found that pHly-1 also had acid-sensitive anticancer activity.Further alanine scanning analysis of pHly-1 was carried out,and we ob-tained a mutant pHTP-2 with better acid sensitivity,whose IC50(half maximal inhibitory concentration)against A549 cells was 15.68 μmol/L at pH 6.6 and was greater than 100 μmol/L at pH 7.4.At pH 6.6,pHTP-2 could act on various lung cancer cell lines and induce the death of A549 cells by rapid ly-sis;at pH 7.4,500 μmol/L pHTP-2 had weak toxicity to red blood cells(the hemolysis rate was ap-proximately 38％)and primary myocardial cells(the inhibition rate was 49.7％,with P＜0.05).Analy-sis of its charge,particle size,morphology,and secondary structure showed that at pH 6.6,the histidine in the sequence of pHTP-2 was protonated,increasing the positive charge(P＜0.01),decreasing the hy-drated particle size(P＜0.05)and forming an α-helical structure to induce membrane lysis of A549 cells.At pH 7.4,it was deprotonated,the positive charge decreases,a β-sheet structure was formed and self-aggregation occurred,limiting its effect on the A549 cell membrane and showing weak activity.In summary,pHTP-2 could respond to the weakly acidic microenvironment of tumors to exert selective cyto-toxic activity,effectively overcoming the shortcomings of anticancer peptides such as low efficiency and high toxicity.Our findings suggest that it is a high-quality lead molecule for anticancer drugs.