RESUMO
BACKGROUND: Artesunate (ART) has been recognized to induce ferroptosis in various tumor phenotypes, including neuroendocrine tumors. We aimed to investigate the effects of ART on insulinoma and the underlying mechanisms by focusing on the process of ferroptosis. METHODS: The CCK8 and colony formation assays were conducted to assess the effectiveness of ART. Lipid peroxidation, glutathione, and intracellular iron content were determined to validate the process of ferroptosis, while ferrostatin-1 (Fer-1) was employed as the inhibitor of ferroptosis. Subcutaneous tumor models were established and treated with ART. The ferroptosis-associated proteins were determined by western blot and immunohistochemistry assays. Pathological structures of the liver were examined by hematoxylin-eosin staining. RESULTS: ART suppressed the growth of insulinoma both in vitro and in vivo. Insulinoma cells treated by ART revealed signs of ferroptosis, including increased lipid peroxidation, diminished glutathione levels, and ascending intracellular iron. Notably, ART-treated insulinoma cells exhibited a decline in the expressions of catalytic component solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4). These alterations were negated by Fer-1. Moreover, no hepatotoxicity was observed upon the therapeutic dose of ART. CONCLUSION: Artesunate might regulate ferroptosis of insulinoma cells through the SLC7A11/GPX4 pathway.
Assuntos
Cicloexilaminas , Ferroptose , Insulinoma , Neoplasias Pancreáticas , Fenilenodiaminas , Humanos , Artesunato , Glutationa , Ferro , Sistema y+ de Transporte de AminoácidosRESUMO
With the rising demand for renewable energy, photocatalysts are considered the most promising solution to harness solar energy, and the search for photocatalysts with excellent performances remains an urgent task. Here, based on density functional theory (DFT), the photocatalytic properties of MoWS4 are systematically investigated. The MoWS4 monolayer and bilayer are demonstrated as semiconductors with indirect band gaps of 2.01 and 1.48 eV. Moreover, they exhibit high and anisotropic light absorption coefficients of up to â¼105 cm-1 in the visible-ultraviolet region. The intrinsic band edge positions could fully satisfy the redox potentials of water without any external adjustment. The electron mobility of MoWS4 monolayer is 557 cm2 V-1s-1, which is seven times higher than MoS2 monolayer. Hence, MoWS4 can be regarded as a promising 2D photocatalyst candidate for water splitting.
RESUMO
The effect of compound fields of ultrasonic vibration and applied pressure (UV+AP) on three-dimensional (3D) microstructure and tensile properties of recycled Al-Cu-Mn-Fe-Si alloys was systematically studied using conventional two-dimensional (2D) microscopy, synchrotron X-ray tomography, and tensile test. The properties of UV+AP treated alloys with the pouring temperature of 740, 710 and 680 °C were compared when those alloys achieved after gravity casting. After UV+AP treatment, the alloy with pouring temperature of 710 °C show the smallest grain size. Also, the sizes of Fe-rich phases and Al2Cu are greatly reduced and their 3D morphologies are compacted. The mechanical properties of UV+AP treated alloys are relatively higher than those measured for gravity cast equivalents. This improvement can be explained by the synergistic effect of acoustic cavitation, acoustic streaming, and force-feeding, which resulted in the dendrite fragmentation, uniform solute distribution, and microstructural refinement. The Orowan strengthening and solution strengthening were identified as the main strengthening mechanisms.
RESUMO
HfO2-based unconventional ferroelectric materials were recently discovered and have attracted a great deal of attention in both academia and industry. The growth of epitaxial Si-doped HfO2 films has opened up a route to understand the mechanism of ferroelectricity. Here, we used pulsed laser deposition to grow epitaxial Si-doped HfO2 films in different orientations of N-type SrTiO3 substrates. Polar nanodomains can be written and read using piezoforce microscopy, and these domains are reversibly switched with a phase change of 180°. Films with different thicknesses displayed a coercive field Ec and a remnant polarization Pr of approximately 4-5 MV/cm and 8-32 µC/cm2, respectively. X-ray diffraction and high-resolution transmission electron microscopy (HRTEM) results identified that the as-grown Si-doped HfO2 films have strained fluorite structures. The ABAB stacking mode of the Hf atomic grid observed by HRTEM clearly demonstrates that the ferroelectricity originates from the noncentrosymmetric Pca21 polar structure. Combined with soft X-ray absorption spectra, the results showed that the Pca21 ferroelectric crystal structure manifested as an O sublattice distortion by the effect of the interface strain and Si dopant interactions, resulting in a nanoscaled ferroelectric ordered state because of further crystal splitting.
RESUMO
To explore the characteristics of localization and prognostic implication of Ezrin expression in HCC, 92 cases of HCC meeting strict follow-up criteria were selected for immunohistochemical staining of Ezrin protein. Correlations between Ezrin expression and clinicopathological features of HCC were evaluated using Chi-square tests, survival rates were calculated using the Kaplan-Meier method, and the relationship between prognostic factors and patient overallsurvival was analyzed using Cox proportional hazard analysis. In results, Ezrin protein was mainly expressed in the inner side of the cell membrane of the adjacent non tumor tissues, and diffusely expressed in cytoplasm of HCC tissues. There was an obviously difference between the benign and malignant tissues about the location of Ezrin expression. Ezrin strong-expression rates were significantly higher in HCC samples compared with the adjacent non tumor tissues (P<0.05). The Ezrin strong-expression rate was closely related with the differentiation (P<0.01), AJCC stage and metastasis of HCC (P<0.05, respectively). Therefore, the sub-cellular localization of Ezrin protein in the liver cells will be changed in the process of the transformation from the benign to malignant, and Ezrin plays an important role in the progression of HCC.