课程文献中心 更多>>

关键词： Cervical cancer   Adenosinergic pathway   TGF-β1   PD-L1   PD-1   Immunosuppression   CD8+ T lymphocytes  

摘要： The PD-1/PD-L1 signaling pathway plays a pivotal role in dampening anti-tumor immune responses. We previously reported that adenosine (Ado) increases the expression of programmed death ligand 1 (PD-L1) in cervical cancer (CC) cells by inducing TGF-β production. We also showed that supernatants from Ado-treated CC cells increased programmed cell death protein 1 (PD-1) expression in CD8+ T lymphocytes. In this study, we investigated the associations between PD-L1, CD73, and TGF-β expression and the percentage of PD-1-expressing CD8+ T lymphocytes in cervical tissue samples from normal donors (NDs), as well as patients with cervical intraepithelial neoplasia (CIN-I, CIN-II, CIN-III) and cervical cancer (CC). This retrospective observational study analyzed biopsies from untreated patients with CIN-1 (n = 27), CIN-II (n = 25), CIN-III (n = 23), and CC (n = 23), in addition to ND tissue samples (n = 30) as controls. Tissue microarrays (TMAs) were generated in triplicate and stained with anti-PD-L1, anti-CD73, anti-TGF-β1, anti-PD-1, and anti-CD8 monoclonal antibodies. Our results showed that the expression of PD-L1, CD73, and TGF-β1, along with the percentage of CD8+/PD-1 + T cells, increased in cervical tissues, correlating with disease progression. PD-L1 expression positively correlated with both CD73 (r = 0.8274, p < 0.001) and TGF-β1 (r = 0.8535, p < 0.001). Interestingly, the coexpression of PD-L1 and TGF-β1 in cervical tissues from patients with CIN-III and CC markedly increased. Furthermore, the percentage of CD8+ cells positively correlated with PD-1 expression (r = 0.7199, p < 0.01). These findings suggest that the expression of PD-L1 and PD-1 in CC tissues is strongly correlated with the expression of CD73 and TGF-β1. Therefore, the joint analysis of these biomarkers could be highly useful for evaluating disease prognosis and for

关键词： 11β-HSD1 inhibitors   And Dynamics simulation   Antidiabetic drug discovery   Machine learning   Molecular docking   Steroidal pregnanes  

摘要： The enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) is a validated therapeutic target for type 2 diabetes mellitus due to its role in local regeneration of active glucocorticoids. Current inhibitors are often limited by their constrained chemical diversity, moderate potency, and off-target effects. The therapeutic potential of steroidal pregnanes in diabetes and metabolic disorders is widely reported; however, their molecular targets, particularly in glucocorticoid signaling, remain poorly understood. This study explored the interactions of a curated library of steroidal pregnanes with 11β-HSD1 using integrated Machine Learning (ML)-based QSAR, molecular docking, 100 ns Molecular Dynamics (MD) simulations, and MM-GBSA binding free energy calculations. Initial exploratory chemical space analysis of the IC₅₀ bioactivity dataset revealed that hydrogen donors, molecular weight, and lipophilicity may contribute to the bioactivity of 11β-HSD1 inhibitors. Evaluation of 42 ML algorithms based on performance metrics revealed Random Forest Regressor (RFR) as a top model for bioactivity predictions. Molecular docking simulation of the top RFR-predicted compounds (pIC₅₀ ≥ 6.0 and pKi ≥ 7.8) with the active site of 11β-HSD1 identified three compounds (pregnane-3, 20-diol disulphate (P1), 20-Piperidin-2-yl-5α-pregnan-3β,20-diol (P2), and 12,20-di-O-benzoyl-pregnane-3β,12β,14β,20-tetraol (P3)). While the reference carbenoxolone primarily involved peripheral polar contacts to stabilize its orientation, the pregnane scaffolds demonstrated deeper insertion into the hydrophobic catalytic cavity of 11β-HSD1, resulting in enhanced shape complementarity and van der Waals packing. The thermodynamic parameters computed from the MD simulation trajectories revealed both the structural stability and intrinsic conformational flexibility of the 11β-HSD1–pregnane complexes. Moreover, the lower MM-GBSA binding energies of P1 (-43.58 kcal/mol) and P

关键词： 1-Ethyl-2-pyrrolidone   Carbon dioxide   Hydrogen   Methane   Modeling   Solubility  

摘要： The solubilities of CO₂, H₂, and CH₄ in 1-ethyl-2-pyrrolidone (NEP) were measured using the isochoric saturation method at 413.15–453.15 K under pressures of 0.45–3.89 MPa (CO₂), 4.42–7.64 MPa (H₂), and 0.59–3.49 MPa (CH₄). The reliability of the apparatus was verified by measuring CO₂ solubility in N-methyl-2-pyrrolidone (NMP) at 323.15–353.15 K. The solubility order in NEP was found to be CO₂ > CH₄> H₂. Temperature-dependent Henry’s constants were obtained, and the experimental data were correlated using the Krichevsky–Kasarnovsky equation and the generic Redlich–Kwong (RK) cubic equation of state, with the RK model providing better accuracy. These results offer essential thermodynamic data for describing gas–liquid equilibrium in NEP and support solvent selection and process design in high-temperature CO₂ conversion systems.

关键词： Lie symmetries   Classical symmetries   Nonclassical symmetries   Analytic solutions   Traveling wave solution   Solitons   Konopelchenko-Dubrovsky-Kaup-Kupershmidt equation  

摘要： In this work, we investigate the (3+1)–dimensional generalized Konopelchenko-Dubrovsky-Kaup-Kupershmidt (gKDKK) equation, which serves as a model for various nonlinear behaviours encountered in fluid mechanics, plasma physics and ocean dynamics. Initially, six–dimensional classical symmetries are determined by using Lie symmetry analysis. Subsequently, we conduct a nonclassical symmetry analysis and identify several hidden symmetries. Moreover, physically relevant solutions, including traveling wave solutions, are derived using the traveling wave transformation. Finally, we examine the dynamics of various solutions, such as one-soliton, multisoliton, peakon-type soliton, wave like, exponential type and parabolic-type solution profiles, along with their graphical behaviours.

关键词： Zirconium alloys   Phase transformation   Orientation relationship   Martensitic twinning   Precipitation   Solute segregation  

摘要： Two types of orientation relationship (OR) Burgers and Potter can be observed during the phase transformation between the α and β phases in Zr alloys. In this work, electron back scatter diffraction and high-resolution transmission electron microscopy were carried out to characterize Potter OR in the solution-treated and subsequently annealed Zr alloys. Our results reveal the presence of Potter OR between parent β-Zr and {10$\overline{1}$1}_α twinning Martensite, elucidating the unique variant selection of {10$\overline{1}$1} twins with in a single α-Zr grain in solution-treated samples. Significantly, a novel, non-stress induced, twinning mechanism was proposed via direct phase transformation based on Potter OR in Martensite. Upon annealing, the OR between β-Zr within the twinning Martensite and α-Zr retains Potter OR, independent of the element segregation at twin boundary. The occurrence of Potter OR instead of Burgers OR is attributed to the lower formation energy of Potter OR upon twinning based on our calculation. These results demonstrate an intrinsic association between Potter OR and the formation of {10$\overline{1}$1} twins, shedding light on the designing of novel high-performance Zr alloys.

关键词： Diabetes   Liver injury   TNF-α/iNOS/TIMP-1 axis   Glycogen   Collagen   Metformin  

摘要： Excessive production of nitric oxide by inducible nitric oxide synthase (iNOS) contributes to liver injury. Diabetes can lead to liver injury and fibrosis, through episodes of nitrosative stress, driven by activation of the inflammation/iNOS pathway. In this study, type 2 diabetes mellitus (T2DM) was induced in rats while another group started the treatment with the antidiabetic drug metformin (200 mg/kg) starting two weeks prior to diabetes induction and continuing until the animals were culled at week 12. Liver injury secondary to T2DM was confirmed 10 weeks after the induction of hyperglycemia as demonstrated by a significant (P < 0.0001) increase in blood and hepatic tissue levels of liver injury biomarkers, tumor necrosis factor-alpha (TNF-α), iNOS, and tissue inhibitor of metalloproteinases-1 (TIMP-1). Glycemia also caused profound liver tissue damage, depletion of glycogen and deposition of collagen. However, these pathological changes and markers of hepatic injury were markedly attenuated in the metformin-treated group. In addition, a significant correlation between nitrosative stress, glycemia, inflammation, glycogen depletion, TIMP-1, and collagen deposition (fibrosis) was observed. These findings demonstrate that diabetes adversely affects hepatic glycogen stores and causes liver tissue injury, as well as upregulating the TNF-α/iNOS/TIMP-1 fibrosis axis while being protected by metformin.

关键词： Flexural strength   MXene   Si3N4   TiC nanosheets   Wave-absorbing composite  

摘要： This study reports a novel method to synthesize porous TiC nanosheets from Ti₃C₂T_x MXene templates for fabricating high-performance microwave-absorbing composites. When TiC nanosheets were mixed with paraffin, the composite exhibited electromagnetic wave absorption performance comparable to that of MXene at a low loading of only 35 wt%, achieving an effective absorption bandwidth (EAB) of 3.6 GHz. The nanosheets were integrated into a porous Si₃N₄ matrix via gel-casting and in-situ nitridation, forming TiC_xN_1-x/Si₃N₄. At 25 wt% loading, the composite possessed a flexural strength of 87.53 MPa and a density of 1.70 g/cm³. It achieved a minimum reflection loss of −27.25 dB and an EAB of 1.98 GHz. Remarkably, the composite retained an EAB of 1.73 GHz at 800 °C, a stability attributed to a protective TiO₂ layer forming on the nanosheet surfaces. This template-derived synthesis offers a viable route to lightweight, mechanically robust, and thermally stable microwave absorbers.

关键词： Paulownia tomentosa   Lambda-cyhalothrin   Thyroid toxicity   Oxidative stress   Apoptosis   Endocrine disruption  

摘要： Pyrethroid pesticides are recognized endocrine disruptors that can disrupt hormonal homeostasis in vertebrates, particularly thyroid function. This study investigated whether an ethanolic extract of Paulownia tomentosa leaves (PLE) could alleviate lambda-cyhalothrin-induced (LCT) thyroid toxicity in mice. The phenolic profile of PLE was confirmed by HPLC, and cytotoxicity was assessed using the MTT assay, which identified 9 mg/kg body weight as a suitable dose. Twenty adult male mice were divided into four groups: control, PLE alone (9 mg/kg), LCT alone (2 mg/kg), and combined PLE+LCT treatment for 28 days. LCT exposure produced marked thyroid dysfunction, reflected by increased serum TSH and reduced T₃ and T₄, accompanied by elevated MDA and pro-inflammatory cytokines, reduced antioxidant enzyme activities, and intensified apoptotic responses. Gene expression analysis demonstrated significant downregulation of thyroid hormone synthesis genes (Slc5a5/NIS, Tpo, Tg) and antioxidant defense markers (Nfe2l2/Nrf2, Hmox1/HO-1), alongside pronounced upregulation of inflammatory genes (Tnf, Il1b) and pro-apoptotic mediators (Bax, Casp3), with suppression of Bcl2. Histological alterations included follicular degeneration, colloid depletion, and reduced follicle diameter. Co-administration of PLE substantially attenuated these biochemical, molecular, and structural alterations, restoring thyroid-related and antioxidant gene expression, reducing inflammatory and apoptotic markers, and partially normalizing follicular morphology. These protective effects likely relate to the phenolic constituents of PLE, which possess recognized antioxidant and anti-inflammatory activities. Overall, PLE demonstrates potential as a natural complementary agent against LCT-induced thyroid injury. Further studies are warranted to isolate the bioactive compounds and clarify their mechanisms.

关键词： Differential scanning calorimetry  

摘要： Lithium-ion battery (LIB) thermal stability is conceivably improvable with various cathode surface coatings. In this study, LiCoO2 (LCO) cathode composites were coated with a thin layer of poly(3,4-ethylenedioxythiophene) (PEDOT) polymer coating, electrochemically charged, carefully transferred to differential scanning calorimetry (DSC) capsules to prevent disturbance to electrolyte and film structure, and evaluated for thermal reactivity. DSC showed that PEDOT reduces the heat release of LCO and electrolyte decomposition reactions between 150 and 400 °C by nearly 75%, and this reductivity is mostly unaffected by electrolyte content. The tendency for PEDOT to stabilize LCO thermal reactivity indicates that PEDOT may be an effective thermal runaway suppressant in full cell LIB designs. Copyright © 2026 ASME.

关键词： Classification   Laser-induced breakdown spectroscopy (LIBS)   Mars   Principal component analysis (PCA)   Tianwen-1  

摘要： Laser-Induced Breakdown Spectroscopy (LIBS) is an analytical technique used to determine the chemical compositions of Martian materials. The Mars Surface Composition Detector (MarSCoDe), carried by the Zhurong Rover, is a powerful instrument for analyzing the chemical compositions of rocks and soils at the Tianwen-1 landing site. The varied environment and diverse lithologies pose significant challenges for the quantitative analysis of chemical compositions. Therefore, we propose a rapid method based on Principal Component Analysis (PCA) to classify Martian rocks and soils using on-board calibration targets acquired with the same instrument and under identical environmental conditions as the in-situ rock/soil spectra—thus eliminating instrument and environmental discrepancies. This model demonstrates good performance when applied to LIBS spectra from ChemCam calibration targets and Martian materials, indicating its applicability to MarSCoDe data. Cluster analysis of MarSCoDe measurements indicates the presence of altered minerals (e.g., montmorillonite) near the landing site, although the degree of alteration appears minor. This indicates a weak aqueous alteration process, possibly resulting from interactions with atmospheric water or groundwater. This study presents a method for rapidly identifying mineral types on the Martian surface using LIBS spectroscopy. This method provides a framework for the quantitative interpretation of MarSCoDe data and offers important insights into the geological origin and hydrological evolution of the landing region.