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关键词： Heusler alloy   High-pressure effect   Magnetism   Martensitic phase transformation  

摘要： Based on first-principles calculations, we have investigated the magnetism, martensitic transformation, elasticity, and thermodynamics of Ni₂FeGa₁₋ₓZnₓ Heusler alloys, focusing on magnetic shape memory alloy applications. The mechanical properties are calculated for such alloys in the tetragonal phase. The martensitic transformation temperature for Ni₂FeGa, Ni₂FeZn, and Ni₂FeGa₀.₅Zn₀.₅ show a linear response with respect to hydrostatic pressure, while Ni₂FeGa₀.₇₅Zn₀.₂₅ and Ni₂FeGa₀.₂₅Zn₀.₇₅ are more sensitive to pressure with a quadratic function. Thermodynamical properties (Gibbs free energy, heat capacity, etc.) are calculated for such alloys, where the martensitic transformation temperature is considered. This work provides insights for designing pressure-based magnetic shape memory alloy sensors.

关键词： Antibacterial   Anticancer   Methylene blue   Nanoparticles   Photoluminescence   Precipitation  

摘要： Novel Pr_xSm_yZn_1-x-yO nanoparticles are prepared by the chemical precipitation method. The doping concentrations of praseodymium and samarium are selected to be equal, with values established at 0, 1, 3, and 5%. The crystallite size, strain and lattice constants are examined from the XRD data. The prepared nanoparticles show a higher band gap of 3.654 eV when the doping concentration is set at 5%. The electron and hole concentration is in the order of 10²⁵-10²⁶/m^3. The refractive index of the prepared materials is examined as a function of the doping concentration. The quenching is observed in the photoluminescence spectrum when the doping is done. The nanoparticles exhibit remarkable antibacterial efficacy against the bacterial strains considered in this work. Furthermore, the anticancer properties of both undoped and doped nanoparticles are meticulously examined against the human breast cancer cell line. The ZnO nanoparticles exhibited 90% inhibition of breast cancer cell proliferation, whereas 5% Pr, Sm dual-doped ZnO nanoparticles showed 94% inhibition at 30 μg/mL. The IC50 value has been significantly ($P<0.05$) reduced from 10.72 ± 0.05 to 9.1 ± 0.05 μg/mL upon doping proves the potential of Pr, Sm dual-doped ZnO nanoparticles as an anticancer agent. The degradation of methylene blue under visible light is explored. The degradation efficiency, reusability, and kinetic rate constants are analyzed.

关键词： Biomarker   Integrin α2β1   Therapeutic target   Tumor microenvironment  

摘要： The integrin family mediates interactions between cells and the extracellular matrix, and plays a pivotal role in the tumor microenvironment. Integrin α2β1, a ubiquitously expressed collagen receptor, is frequently overexpressed in various solid tumors, such as glioblastoma, pancreatic cancer and lung cancer, and plays a critical role in tumor progression. Studies have demonstrated that α2β1 promotes cancer progression by regulating a complex pro-tumorigenic network through multiple mechanisms, including tumor cell proliferation, local invasion and distant metastatic colonization. Recent research has also revealed the role of α2β1 in inducing tumor stem cell phenotypes, as well as its potential as a diagnostic, prognostic biomarker and therapeutic target. In this review, we will examine the diverse functions of α2β1 in cancer progression and explore how these insights can inform the development of therapeutic strategies to overcome drug resistance and metastasis.

关键词： Esophageal squamous cell carcinoma (ESCC)   Immune-cold tumor   Murine cell line   Murine syngeneic model   PD-1 resistance  

摘要： Immunotherapy has revolutionized the treatment of esophageal squamous cell carcinoma (ESCC), but its clinical application is limited by low response rates and acquired resistance. The exploration of underlying is hampered by the absence of preclinical models that faithfully recapitulate the immune microenvironment and drug-resistant features of ESCC. Here, we established a novel murine ESCC cell line named mESCC-030, which was derived from primary ESCC tumors induced by 4-Nitroquinoline N-oxide (4-NQO) in C57BL/6 mice via consecutive in vivo selection. This cell line was validated by morphological observation and STR identification. Compared with primary parental cells, mESCC-030 exhibits stronger malignant proliferation, invasion and migration capabilities, and achieves 100% subcutaneous tumorigenicity in C57BL/6 mice. Moreover, the syngeneic graft tumors derived from this cell line display prominent resistance to PD-1 antibody therapy. Bulk transcriptomic profiling revealed that this cell line harbors enhanced proliferation-related pathways and diminished immune response pathways. Single-cell RNA sequencing of graft tumors identified a highly proliferative cell cluster in tumor tissues, along with an extremely low proportion of immune infiltrating cells. Taken together, the mESCC-30 cell line and its syngeneic tumors represent a typical immune-cold tumor model, providing a novel platform to uncover immunotherapy resistance mechanisms and develop combination therapeutic strategies.

关键词： Alzheimer's disease   Equol   UPRer  

摘要： Alzheimer's disease (AD) is the leading cause of dementia with no effective disease-modifying treatments. Here, we found that Escherichia coli (E. coli) DH5α relieved learning defects and paralysis, and prolonged lifespan in amyloid-β (Aβ)-expressing C. elegans. DH5α inhibited Aβ aggregation via activating the PEK-1-dependent endoplasmic reticulum unfolded protein response (UPRer). We further identified equol from DH5α metabolites, which alleviated AD-related phenotypes through the same PEK-1/UPRer pathway.

关键词： Chondrocytes   Ferroptosis   GPX4/SLC7A11   IL-1β   Osteoarthritis   β-Sitosterol  

摘要： To investigate the effect of β-Sitosterol on interleukin (IL)-1β-induced chondrocyte injury and the related mechanism.

关键词： Alcohol oxidation   Pt nanoparticles   Silicalite-1 zeolite   Solvent effect   Fatty acids  

摘要：

• •
  Hydrothermal defect healing selectively stabilizes catalytically active Pt ensembles by removing weakly anchored species in Silicalite-1.
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  Confined Pt ensembles exhibit enhanced intrinsic activity, lower activation energy, and improved oxygen activation in aerobic alcohol oxidation.
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  Catalysis occurs on externally accessible Pt sites and mesoporous regions, enabling efficient oxidation of bulky alcohol molecules.
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  Defect-healing-induced restructuring provides a general strategy to optimize active site stability and catalytic efficiency in heterogeneous oxidation catalysts.

关键词： 18β-glycyrrhetinic acid compound   Antibacterial activities   Crystal structure   DFT study   Molecular docking   Synthesis  

摘要： In this paper, the title compound was synthesized via a one-pot, two-step method using 18β-glycyrrhetinic acid (GA) as the starting material. (2S,10S)-10-(((N-(4-fluorophenyl)sulfamoyl)carbamoyl)oxy)-2,4a,6a,6b,9,9,12a-heptamethyl-13-oxo-1,2,3,4,4a,5,6,6a,6b,7,8,8a,9,10,11,12,12a,12b,13,14b-icosahydropicene-2-carboxylic acid was designed and synthesized, and the structure was characterized by spectroscopic techniques including UV–vis, FT-IR, Raman, ¹H NMR, ¹³C NMR and HRMS. The single crystal structure of the target molecule was confirmed by X-ray diffraction, revealing OH···O and CH···O hydrogen-bonding interactions as the key factors governing crystal packing. The geometrical parameters, molecular electrostatic potential (MEP), and frontier molecular orbital analysis (FMOs) of the molecule are also presented to reveal the physicochemical properties of the investigated compound. In addition, Hirshfeld surface analysis of the title molecule by using crystal information file, a significant contribution (22.6%) to the crystal packing comes from O^…H contacts. The title compound exhibited MIC values of 17.17 and 68.69 μg⋅mL⁻¹ against P. aeruginosa, P. halotolerans and VR E. faecium 4, respectively. The results presented herein demonstrate the compound’s promising antibacterial activity, providing a valuable reference for the synthesis of a novel substituted 18β-glycyrrhetinic acid and facilitating further exploration of their medicinal potential. Additionally, a molecular docking study demonstrated that compound 1 exhibits a notable binding free energy (ΔG = -9.9 kcal/mol). These computational results provi

关键词： Anticancer   Characterization   Imidazo[2,1-b]thiazole   MCF-7 cell line   Molecular docking   Synthesis   X-ray crystallography  

摘要： Thiazole derivatives constitute an important structural motif in several anticancer agents, exhibiting diverse enzyme inhibitory mechanisms, including tyrosine kinase inhibition. The epidermal growth factor receptor (EGFR), which is overexpressed in many cancer types, particularly breast cancer, plays a pivotal role in tumor proliferation; thus, its regulation is crucial for controlling cancer cell growth. In this context, the present study focuses on the design and synthesis of cost-effective thiazole-based analogues with potential anticancer activity. A new series of imidazo[2,1-b]thiazole derivatives 6a-6j was synthesized via multistep condensation reactions under mild conditions using substituted phenacyl bromides and 2-aminothiazoles. The synthesized compounds were thoroughly characterized by ¹H-, ¹³C-, and ¹⁹F-NMR spectroscopy, high-resolution mass spectrometry (HRMS), and single-crystal X-ray diffraction (XRD) analysis. Single-crystal XRD analysis of compound 6b revealed a planar molecular structure stabilized by significant intramolecular hydrogen bonding interactions with supramolecular assembly governed by intermolecular chalcogen and hydrogen bonds. These solid-state intermolecular interactions were investigated using Hirshfeld surface (HS), energy framework (EF), molecular electrostatic potential (MEP), non-covalent interactions (NCI) index, and quantum theory of atoms in molecules (QTAIM) studies. All synthesized derivatives were evaluated for their in vitro anticancer activity using the standard MTT assay against the MCF-7 breast cancer cell line. Among the tested compounds, derivative 6i exhibited notable cytotoxic activity, surpassing the reference drug cisplatin. Overall, the results highlight the anticancer potential of this novel imidazo[2,1-b]thiazole scaffold, with compound 6i emerging as a promising lead for further de

关键词： ADD   DFT   Emission spectra   NLO   Sensor   UV-vis spectra  

摘要： The current study focuses on the newly synthesised acridine-1,8-dione-based fluorescent probe (PPADD) as a detector of hydroxide ions. PPADD shows absorption maxima at ∼ 370 nm in DMSO and red shifted from 370 nm to 460 nm only after the addition of hydroxide ion with a conspicuous colour change from colourless to yellow. Whereas it exhibits emission peak at 435 nm when excited at 370 nm and fluorescence enhancement at ⁓510 nm was noticed only in the presence of OH^-. Dual mode of detection (colorimetric, fluorometric), high selectivity, fast response time indicate its potential for the use in real field applications. To explore the electronic and opto-electronic behaviour of PPADD, Density Functional Theory was accompanied. The effect of solvent on the probe molecule was studied using PCM model. After analysing the solvent effects, it was seen that PPADD exhibits better NLO response in polar mode in both static and dynamic cases, which suggest its plausible application in optical technologies. Higher NLO responses were found at 532 nm compared to 1064 nm in various solvents. Moreover, a higher non-linear refractive index suggests its superiority as a NLO material. The results also show that proton abstraction can increase the NLO response providing higher β_HRS values.