Recent studies have indicated that the expression of ubiquitin-specific protease 51 (USP51), a novel deubiquitinating enzyme (DUB) that mediates protein degradation as part of the ubiquitin‒proteasome system (UPS), is associated with tumor progression and therapeutic resistance in multiple malignancies. However, the underlying mechanisms and signaling networks involved in USP51-mediated regulation of malignant phenotypes remain largely unknown. The present study provides evidence of USP51's functions as the prominent DUB in chemoresistant triple-negative breast cancer (TNBC) cells. At the molecular level, ectopic expression of USP51 stabilized the 78 kDa Glucose-Regulated Protein (GRP78) protein through deubiquitination, thereby increasing its expression and localization on the cell surface. Furthermore, the upregulation of cell surface GRP78 increased the activity of ATP binding cassette subfamily B member 1 (ABCB1), the main efflux pump of doxorubicin (DOX), ultimately decreasing its accumulation in TNBC cells and promoting the development of drug resistance both in vitro and in vivo. Clinically, we found significant correlations among USP51, GRP78, and ABCB1 expression in TNBC patients with chemoresistance. Elevated USP51, GRP78, and ABCB1 levels were also strongly associated with a poor patient prognosis. Importantly, we revealed an alternative intervention for specific pharmacological targeting of USP51 for TNBC cell chemosensitization. In conclusion, these findings collectively indicate that the USP51/GRP78/ABCB1 network is a key contributor to the malignant progression and chemotherapeutic resistance of TNBC cells, underscoring the pivotal role of USP51 as a novel therapeutic target for cancer management.

An ideal dermal filler should integrate filling, repair, and anti-aging effects, with immediate tissue augmentation, slow degradation, and progressive stimulation of collagen regeneration. However, commonly used hyaluronic acid (HA) hydrogels, while effective for rapid filling, suffer from limited duration of support, weak cell adhesion, and an inability to promote collagen regeneration. Silk fibroin (SF), a natural protein from silkworm cocoons, is known for its excellent cell adhesion and collagen-stimulating abilities. However, its limited gelation capability restricts its potential application as a standalone injectable hydrogel. Based on a complementary strategy, this study combines the rapid gelling properties of HA with the collagen regenerative properties of SF to create a co-crosslinked HA-SF hydrogel. The composite hydrogel merges HA's rapid filling effect with SF's strong tissue adhesion and collagen-stimulating abilities. The formulation, physicochemical properties, degradation, biocompatibility, and filling effects of the HA-SF hydrogel were systematically investigated. HA-SF hydrogel exhibits excellent mechanical properties and ensures long-term support while maintaining injectability. Interestingly, after intradermal injection in the UVB-induced photoaging model, HA-SF hydrogel not only enhances hydrogel-cell interaction but also continues to stimulate collagen regeneration, especially type III collagen. This dual action achieves the biological effects of repair and anti-aging while maintaining the filling effect. Proteomic analysis confirms that repair and anti-aging effects are enhanced by the regulation of skin fibroblasts and modulation of amino acid and lipid metabolism. This composite hydrogel holds strong promise for clinical applications, offering a safer, long-lasting, and more natural injectable filler that combines filling, repair, and anti-aging into one system.

Objective·To explore the mechanism at the atomic level by which the KRASG12D/R68G mutation induces tumor cell resistance to MRTX1133.Methods·The crystal structure data of the KRASG12D-MRTX1133 complex were obtained from the RCSB Protein Data Bank(PDB).PyMOL software was used to mutate arginine at position 68 of KRAS to glycine(R68G),constructing the initial conformations of the KRASG12D-MRTX1133 and KRASG12D/R68G-MRTX1133 complexes.The LEaP module was used to build simulation systems under periodic boundary conditions.The ff19SB force field was applied to standard amino acids in KRAS,GAFF(general AMBER force field)to MRTX1133,and TIP3P(intermolecular potential three point)to water molecules.Energy minimization was performed using the Amber software suite.The systems were then heated to 300 K,followed by NVT(constant volume and temperature)equilibration and NPT(constant pressure and temperature)production.Root mean square deviation(RMSD),root mean square fluctuation(RMSF),principal component analysis(PCA)and solvent-accessible surface area(SASA)of MRTX1133 and GDP were analyzed using cpptraj.The number of hydrogen bonds between regions and the dynamic cross-correlation matrix(DCCM)of amino acid movements were also calculated.Results·RMSD analysis showed greater structural variation in KRAS in the KRASG12D/R68G system compared to the KRASG12D system.RMSF analysis revealed significantly higher fluctuations in the Switch Ⅰ and Switch Ⅱ regions of the KRASG12D/R68G system.PCA indicated that Switch Ⅰ and Switch Ⅱ in the KRASG12D/R68G system were more frequently in an open conformation.The distances between Switch Ⅰ and the P-loop,and between Switch Ⅱ and the P-loop,were larger in the KRASG12D/R68G system,indicating an expanded binding pocket for GDP and MRTX1133 compared to the KRASG12D system.SASA analysis indicated that both GDP and MRTX1133 had increased solvent exposure in the KRASG12D/R68G system.DCCM analysis revealed more decoupled movements among the Switch Ⅰ,Switch Ⅱ and P-loop regions in the KRASG12D/R68G system.Conclusion·The KRASG12D/R68G mutation disrupts the interactions between the Switch Ⅰ and Switch Ⅱregions,leading to their separation and the opening of the MRTX1133 binding pocket.This increases the solvent exposure of MRTX1133,accelerates its dissociation,and ultimately results in KRASG12D/R68G resistance to MRTX1133.

Objective:To evaluate the detection rate, anatomical distribution, and influencing factors of bone marrow edema-like signal (BMELS) in the knees of amateur marathon runners.Methods:This was a cross-sectional study. This study publicly recruited amateur marathon runners through the Hangzhou Long-distance Running Association from January 2019 to December 2024. Based on knee magnetic resonance imaging (MRI) results, participants were divided into a BMELS-positive group (BMELS present in at least one knee) and a BMELS-negative group. General clinical information was collected from participants using a questionnaire. All participants underwent a knee MRI scan to screen for the presence of BMELS and to assess its severity. Logistic regression models were used to analyze the associated factors of BMELS in amateur marathon runners, while Spearman′s correlation analysis assessed the correlation between BMELS grade and these factors.Results:A total of 60 subjects (120 knee joints) were enrolled, including 39 males (65%), aged (40.0±8.4) years. Of these, 39 were in the BMELS-positive group, and 21 were in the BMELS-negative group. The BMELS detection rate for the 120 knee joints of these 60 subjects was 53.3% (64/120). BMELS were detected in 43.3%(52/120) of the femur, 34.2% (41/120) of tibia and 17.5% (21/120) of patella. Multivariate logistic regression analysis showed an independent positive correlation between monthly running volume and knee BMELS in amateur marathon runners ( OR=1.007, 95% CI: 1.000-1.013, P=0.035). Spearman′s correlation analysis showed a weak positive correlation between the BMELS grade of the knees and the monthly running volume of amateur marathon runners ( r s=0.360, P=0.005). Conclusions:The detection rate of knee BMELS is high in amateur marathon runners, and they are distributed in a way that is characteristic of the region, with a higher incidence in the medial femoral condyle. In this population, monthly running volume is independently associated with knee BMELS, with a higher grade associated with greater monthly running volume.

Objective To investigate the differences in Mandarin vowel space area(VSA)across geographic regions and genders.Methods Healthy college students residing in Beijing(62 cases,32 males and 30 females)and Shanghai(62 cases,32 males and 30 females)were selected to study the Mandarin VSA with six Chinese vowels(/a/,/e/,/i/,/u/,/o/,/ü/,and the short text Vacation)as the corpus,respectively.Results The differences in VSA between genders were extremely significant(P＜0.001),and the VSA of females was significantly larger than that of males.Simple effect tests for speech material and region showed that when the speech material was con-tinuous speech,the VSAs of Beijing and Shanghai subjects showed no significant difference,but when the speech material was unitary speech,the VSAs of Shanghai subjects were significantly larger than those of Beijing subjects(P=0.003,P＜0.01).Conclusion The VSAs of female adults were larger than those of male adults,and the front vowels of females were more fronted and the back vowels were more backward.The differences produced by different regions based on the Mandarin system of pronunciation were not significant.

ObjectiveTo explore the target of Erzhiwan in reducing myocardial injury in ovariectomized mice through non-targeted myocardial metabolomics combined with experimental verification. MethodsOvariectomized mouse model was selected， 40 female C57BL/6 mice were randomly divided into sham operation group， model group， estrogen group（estradiol valerate， 1.3×10^-4 g·kg^-1）， Erzhiwan low and high dose groups（3.12， 9.36 g·kg^-1）， with 8 mice in each group. Each administration group was given the corresponding dose of Erzhiwan by gavage， and the sham operation group and model group were given equal volume of distilled water by gavage for 12 weeks. Echocardiography was used to detect cardiac function， hematoxylin-eosin（HE） staining was used to observe myocardial morphological changes， and enzyme-linked immunosorbent assay（ELISA） was used to detect the levels of estrogen， N-terminal pro-brain natriuretic peptide（NT-proBNP）， hypersensitive troponin T（hs-TnT）， total cholesterol（TC）， triglyceride（TG）， low density lipoprotein cholesterol（LDL-C）， high density lipoprotein cholesterol（HDL-C）， interleukin（IL）-1β， IL-18 and tumor necrosis factor-α（TNF-α）. The non-targeted metabolomics of mouse myocardium were analyzed by ultra performance liquid chromatography-quadrupole-electrostatic field orbital trap high-resolution mass spectrometry（UPLC-Q-Exactive Orbitrap MS）， and the differential metabolites and corresponding metabolic pathways were obtained. The mRNA expression levels of phosphatidylinositol 3-kinase（PI3K） and protein kinase B（Akt） in mouse myocardial tissues were detected by real-time fluorescence quantitative polymerase chain reaction（Real-time PCR）， and the protein expression levels of PI3K， Akt， phosphorylated（p）-Akt were detected by Western blot. ResultsCompared with the sham operation group， the model group showed abnormal cardiac function， increased myocardial fiber space， cardiomyocyte atrophy， sarcoplasmic aggregation， and occasional dissolution or rupture of muscle fiber， the level of estrogen in the serum was decreased， the levels of NT-proBNP， hs-TnT， IL-1β， IL-18， TNF-α， TG， TC and LDL-C were increased， and the level of HDL-C was decreased（P<0.01）. Compared with the model group， Erzhiwan could increase the level of estrogen， improve the abnormal cardiac function， reduce the pathological injury of myocardial tissue， decrease the levels of myocardial injury markers（NT-proBNP， hs-TnT） and inflammatory factors（IL-1β， IL-18， TNF-α）， decrease the levels of TG， TC， LDL-C， and increased the level of HDL-C（P<0.01）. The results of non-targeted myocardial metabolomics showed that 31 of the 162 differential metabolites between the model group and sham operation group were significantly adjusted after administration of Erzhiwan， which were mainly glycerol phospholipid metabolites. Pathway enrichment results showed that Erzhiwan mainly affected glycerophospholipid metabolic pathway， PI3K-Akt pathway， cyclic guanosine monophosphate（cGMP）-protein kinase G（PKG） pathway and other metabolic pathways. Compared with the sham operation group， the levels of phosphatidylcholine（PC， 11 types） and phosphatidylethanolamine（PE， 5 types） in mouse myocardial tissue of the model group were increased（P<0.05， P<0.01）， and the mRNA and protein expressions of PI3K and p-Akt were decreased（P<0.05， P<0.01）. Compared with the model group， the levels of PC（11 types） and PE（5 types） were decreased（P<0.05， P<0.01） in myocardial tissue of Erzhiwan group， the mRNA and protein expressions of PI3K and p-Akt were elevated（P<0.01）. ConclusionErzhiwan can alleviate the pathological injury of myocardium in ovariectomized mice， improve the abnormal cardiac function， improve lipid metabolism disorder， and reduce the levels of myocardial injury markers and inflammatory factors， which involves a number of signaling and metabolic pathways in the heart， among which glycerophospholipid metabolism pathway and PI3K/Akt pathway may have key roles.

Objective: To explore the influencing factors and pathways of suicidal ideation among children and adolescents with severe autism spectrum disorder (ASD), so as to provide references for clarifying the impact intensity and pathways of various factors on suicidal ideation in the population. Methods: A cross sectional study was conducted from June 17, 2024, to January 12, 2025, involving 96 severely affected ASD children and adolescents aged 8-18 years from Tianjin. Participants were assessed using the Puberty Development Scale (PDS), Children s Alexithymia Measure (CAM), Strengths and Difficulties Questionnaire (SDQ), and Positive and Negative Suicide Ideation (PANSI). The random forest Boruta algorithm was employed to screen core variables, and a Bayesian network model was constructed to analyze the influencing factors of suicidal ideation in children and adolescents with severe ASD. Results: Through the screening using the Boruta algorithm, the SDQ scale score, conduct problems, hyperactivity, peer relationship problems and prosocial behavior were identified as the key predictors of suicidal ideation. A Bayesian network model was established with hyperactivity as the central mediating node. The impact of hyperactivity on suicidal ideation exhibited a non linear relationship: compared to the normal state (31.6%, 68.4%), the borderline state of hyperactivity was associated with a higher probability of low risk suicidal ideation (47.1%) and a lower probability of high risk suicidal ideation (52.9%). Suicidal ideation among children and adolescents with severe ASD was closely related to hyperactivity. In the state of hyperactivity, the abnormal peer relationship (95.2%) and the abnormal prosocial behavior (77.0%) were aggravated. Conclusions Suicide ideation among children and adolescents with severe ASD is strongly associated with hyperactivity traits. It is necessary to establish a prevention and control system centered on hyperactivity intervention to reduce this risk.

Objective To investigate the differences in Mandarin vowel space area(VSA)across geographic regions and genders.Methods Healthy college students residing in Beijing(62 cases,32 males and 30 females)and Shanghai(62 cases,32 males and 30 females)were selected to study the Mandarin VSA with six Chinese vowels(/a/,/e/,/i/,/u/,/o/,/ü/,and the short text Vacation)as the corpus,respectively.Results The differences in VSA between genders were extremely significant(P＜0.001),and the VSA of females was significantly larger than that of males.Simple effect tests for speech material and region showed that when the speech material was con-tinuous speech,the VSAs of Beijing and Shanghai subjects showed no significant difference,but when the speech material was unitary speech,the VSAs of Shanghai subjects were significantly larger than those of Beijing subjects(P=0.003,P＜0.01).Conclusion The VSAs of female adults were larger than those of male adults,and the front vowels of females were more fronted and the back vowels were more backward.The differences produced by different regions based on the Mandarin system of pronunciation were not significant.

Objective To observe the value of endovascular stenting(EVS)for treating transverse sinus stenosis(TSS)-related unilateral pulsatile tinnitus(PT).Methods Totally 42 patients with TSS-related unilateral PT who underwent EVS were retrospectively enrolled.The technical and clinical success rates of EVS for treating TSS-related unilateral PT were evaluated,and the complications and recurrence after treatment were observed.Results Among 42 cases,stent implantation was successfully performed in 40 cases,with the technical success rate of EVS was 95.24%(40/42).After treatment,the tinnitus symptoms in the above 40 cases improved significantly,the tinnitus handicap inventory(THI)score immediately decreased to mild PT,the trans-stenotic pressure gradient(TPG)decreased from 8.00(6.00,11.75)mmHg before treatment to 1.00(1.00,1.00)mmHg,and the clinical success rate of EVS was 100%(40/40).During the follow-up period,no serious complication was found.PT recurred 3 months after treatment in 1 case but spontaneously released 3 months later without any management.Conclusion EVS was safe and effective for treating TSS-related unilateral PT.

Objective To explore the mediating effect of thyroid stimulating hormone(TSH)levels on the risk of osteoporosis(OP)in patients with T2DM and menopause.Methods A total of 179 menopausal T2DM patients who were admitted to our hospital from January 2020 to January 2023 were enrolled in this study.All the participants were divided into diabetes without complication group(T2DM group,n=95)and diabetes with complication group(Com group,n=84)according to the co-existence of complications.Logistic regression analysis was used to analyze the influencing factors for T2DM complications.According to the co-existence of OP,all the patients were divided into OP group(n=86)and Non-OP group(n=93).And the influencing factors for OP occurrence are analyzed using random forest algorithm.Logistic regression analysis was used to investigate the relationship between TSH and T2DM complications and OP.The Bootstrap method was used to analyze the mediating effect of TSH between T2DM complications and OP.Results DM duration,HbA1c,free triiodothyronine,free thyroxine,and TSH were independent influencing factors for T2DM complications(P＜0.05),while P1NP,TSH,vitamin D,and DM duration were influencing factors for the occurrence of OP.After adjusting for confounding factors,there was a negative correlation between TSH and the risk of T2DM complications(P＜0.05),and a negative correlation between TSH and OP(P＜0.05).Mediation effect analysis showed that TSH played a mediating role between T2DM complications and OP.Conclusions TSH is negatively correlated with the risk of T2DM complications and OP,and plays a mediating role between T2DM complications and OP,partially mediating the impact of T2DM complications on OP.