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81.
Necroptosis is the major cause of death in alveolar epithelial cells (AECs) during acute lung injury (ALI). Here, we report a previously unrecognized mechanism for necroptosis. We found an accumulation of mitochondrial citrate (citratemt) in lipopolysaccharide (LPS)-treated AECs because of the downregulation of Idh3α and citrate carrier (CIC, also known as Slc25a1). shRNA- or inhibitor–mediated inhibition of Idh3α and Slc25a1 induced citratemt accumulation and necroptosis in vitro. Mice with AEC-specific Idh3α and Slc25a1 deficiency exhibited exacerbated lung injury and AEC necroptosis. Interestingly, the overexpression of Idh3α and Slc25a1 decreased citratemt levels and rescued AECs from necroptosis. Mechanistically, citratemt accumulation induced mitochondrial fission and excessive mitophagy in AECs. Furthermore, citratemt directly interacted with FUN14 domain-containing protein 1 (FUNDC1) and promoted the interaction of FUNDC1 with dynamin-related protein 1 (DRP1), leading to excessive mitophagy-mediated necroptosis and thereby initiating and promoting ALI. Importantly, necroptosis induced by citratemt accumulation was inhibited in FUNDC1-knockout AECs. We show that citratemt accumulation is a novel target for protection against ALI involving necroptosis.Subject terms: Infection, Respiratory tract diseases  相似文献   
82.
Transarterial chemoembolization (TACE) is the first-line treatment for unresectable intermediate-stage hepatocellular carcinoma (HCC). It is of high clinical significance to explore the synergistic effect of TACE with antiangiogenic inhibitors and the molecular mechanisms involved. This study determined that glucose, but not other analyzed nutrients, offered significant protection against cell death induced by sorafenib, as indicated by glucose deprivation sensitizing cells to sorafenib-induced cell death. Next, this synergistic effect was found to be specific to sorafenib, not to lenvatinib or the chemotherapeutic drugs cisplatin and doxorubicin. Mechanistically, sorafenib-induced mitophagy, as indicated by PINK1 accumulation, increased the phospho-poly-ubiquitination modification, accelerated mitochondrial membrane protein and mitochondrial DNA degradation, and increased the amount of mitochondrion-localized mKeima-Red engulfed by lysosomes. Among several E3 ubiquitin ligases tested, SIAH1 was found to be essential for inducing mitophagy; that is, SIAH1 silencing markedly repressed mitophagy and sensitized cells to sorafenib-induced death. Notably, the combined treatment of glucose restriction and sorafenib abolished ATP generation and mitophagy, which led to a high cell death rate. Oligomycin and antimycin, inhibitors of electron transport chain complexes, mimicked the synergistic effect of sorafenib with glucose restriction to promote cell death mediated via mitophagy inhibition. Finally, inhibition of the glucose transporter by canagliflozin (a clinically available drug used for type-II diabetes) effectively synergized with sorafenib to induce HCC cell death in vitro and to inhibit xenograft tumor growth in vivo. This study demonstrates that simultaneous treatment with sorafenib and glucose restriction is an effective approach to treat HCC, suggesting a promising combination strategy such as transarterial sorafenib-embolization (TASE) for the treatment of unresectable HCC.Subject terms: Liver cancer, Mitophagy, Apoptosis  相似文献   
83.
Ammonia (NH3) is a common pollutant mostly derived from pig manure composting under humid conditions, and it is absolutely necessary to develop materials for ammonia removal with high stability and efficiency. To this end, metal–organic frameworks (MOFs) have received special attention because of their high selectivity of harmful gases in the air, resulting from their large surface area and high density of active sites, which can be tailored by appropriate modifications. Herein, two synthetic metal–organic frameworks (MOFs), 2-methylimidazole zinc salt (ZIF-8) and zinc-trimesic acid (ZnBTC), were selected for ammonia removal under humid conditions during composting. The two MOFs, with different organic linkers, exhibit fairly distinctive ammonia absorption behaviors under the same conditions. For the ZnBTC framework, the ammonia intake is 11.37 mmol/g at 298 K, nine times higher than that of the ZIF-8 framework (1.26 mmol/g). In combination with theoretical calculations, powder XRD patterns, FTIR, and BET surface area tests were conducted to reveal the absorption mechanisms of ammonia for the two materials. The adsorption of ammonia on the ZnBTC framework can be attributed to both physical and chemical adsorption. A strong coordination interaction exists between the nitrogen atom from the ammonia molecule and the zinc atom in the ZnBTC framework. In contrast, the absorption of ammonia in the ZIF-8 framework is mainly physical. The weak interaction between the ammonia molecule and the ZIF-8 framework mainly results from the inherent severely steric hindrance, which is related to the coordination mode of the imidazole ligands and the zinc atom of this framework. Therefore, this study provides a method for designing promising MOFs with appropriate organic linkers for the selective capture of ammonia during manure composting.  相似文献   
84.
For this work, europium monosulfide (EuS) powders were prepared by sulfurizing Eu2O3 powder with CS2 gas. The synthesized EuS powders were sintered by SPS at temperatures in the 800–1600 °C range for 0.33–1 h at 50 MPa under vacuum conditions. The influences of Yb doping and sintering conditions on the magnetocaloric and mechanical properties of EuS were investigated systematically. An increase in sintering temperature caused the rise of lattice parameters of EuS, whereas Yb doping caused them to drop. SEM showed that the grain size of the EuS increased with sintering temperatures in the 1000–1400 °C range. Higher sintering temperatures can enlarge the magnetizability and saturation magnetization of EuS compact. On the contrary, Yb doping can weaken the magnetizability and saturation magnetization of EuS compact. All sintered polycrystalline EuS compacts had weaker thermomagnetic irreversibility and lower magnetic anisotropy.  相似文献   
85.
The use of tetra-alkylcarbamides as novel ligands: N,N-butyl-N’,N’-hexylurea (L1: ABHU), and N,N-butyl-N’,N’-pentylurea (L2: ABPU), for the solvent extraction and complexation behaviors of uranium(VI) was synthesized and investigated in this study. The effects of HNO3 and NO3 concentrations in the aqueous phase on the distribution ratio of U(VI) were examined. Under 5 mol/L HNO3 concentration, DU reached 5.02 and 4.94 respectively without third-phase formation. During the extraction, slope measurements and IR spectral analysis revealed that the U(VI) complexes are a form of UO2(NO3)2·2L for both ligands. In addition, thermodynamic studies showed that the uranium extraction reaction was a spontaneous exothermic reaction. The deep structural analysis of the complexes was realized with DFT calculation. The bond length, bond properties, and topology of the complexes were discussed in detail to analyze the extraction behavior. This study enriches the coordination chemistry of U(VI) by tetra-alkylcarbamides, which may offer new clues for the design and synthesis of novel ligands for the separation, enrichment, and recovery of uranium in the nuclear fuel cycle.  相似文献   
86.
The effective reflective anode remains a highly desirable component for the fabrication of reliable top-emitting organic light-emitting diodes (TE-OLEDs) which have the potential to be integrated with complementary metal-oxide-semiconductor (CMOS) circuits for microdisplays. This work demonstrates a novel laminated anode consisting of a Cr/Al/Cr multilayer stack. Furthermore, we implement an ultra-thin titanium nitride (TiN) layer as a protective layer on the top of the Cr/Al/Cr composite anode, which creates a considerably reflective surface in the visible range, and meanwhile improves the chemical stability of the electrode against the atmosphere or alkali environment. Based on [2-(2-pyridinyl-N)phenyl-C](acetylacetonate)iridium(III) as green emitter and Mg/Ag as transparent cathode, our TE-OLED using the TiN-coated anode achieves the maximum current efficiency of 71.2 cd/A and the maximum power efficiency of 66.7 lm/W, which are 81% and 90% higher than those of the reference device without TiN, respectively. The good device performance shows that the Cr/Al/Cr/TiN could function as a promising reflective anode for the high-resolution microdisplays on CMOS circuits.  相似文献   
87.
88.
Main observation and conclusion A method for photoinduced Nal-promoted radical borylation of aliphatic halides and pseudohalides with bis(catecholato)diboron(B2...  相似文献   
89.
基于介电弹性体的软机器在柔性机器人、能量收集、柔性电子等领域有着广泛的应用.传统的介电弹性器件由不透明的流体碳膏电极或其他硬材料制作的电子导体来驱动.可拉伸透明离子导体作为电极驱动介电弹性体时,两种软材料互相结合,为软机器提供了一种独特的实现方式.论文综述了离子导体驱动的介电弹性体软机器的近期研究进展,展望了未来的研究方向和存在的问题.  相似文献   
90.
The development of novel organic electrode materials is of great significance for improving the reversible capacity and cycle stability of rechargeable batterie...  相似文献   
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