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排序方式: 共有1842条查询结果,搜索用时 140 毫秒
991.
Nicole A. Spiegelman Jun Young Hong Dr. Jing Hu Dr. Hui Jing Miao Wang Dr. Ian R. Price Dr. Ji Cao Dr. Min Yang Dr. Xiaoyu Zhang Prof. Dr. Hening Lin 《ChemMedChem》2019,14(7):744-748
SIRT2, a member of the sirtuin family of protein lysine deacylases, has been identified as a promising therapeutic target for treating cancer. In addition to catalyzing deacetylation, SIRT2 has recently been shown to remove fatty acyl groups from K-Ras4a and promote its transforming activity. Among the SIRT2-specific inhibitors, only the thiomyristoyl lysine compound TM can weakly inhibit the demyristoylation activity of SIRT2. Therefore, more potent small-molecule SIRT2 inhibitors are needed to further evaluate the therapeutic potential of SIRT2 inhibition, and to understand the function of protein lysine defatty-acylation. Herein we report a SIRT2 inhibitor, JH-T4, which can increase K-Ras4a lysine fatty acylation. This is the first small-molecule inhibitor that can modulate the lysine fatty acylation levels of K-Ras4a. JH-T4 also inhibits SIRT1 and SIRT3 in vitro. The increased potency of JH-T4 is likely due to the formation of hydrogen bonding between the hydroxy group and SIRT1, SIRT2, and SIRT3. This is further supported by in vitro studies with another small-molecule inhibitor, NH-TM. These studies provide useful insight for future SIRT2 inhibitor development. 相似文献
992.
993.
Population-balances are a powerful method to predict the population behavior of drops in chemical-engineering equipment such as solvent extraction columns. In such columns a complex interaction of different phenomena, namely drop sedimentation, mass transfer, drop breakage and coalescence as well as axial dispersion occurs. In this article the concept of drop-population balances is discussed in detail as well as possible solution methods. Also, a critical review of existing models accounting for breakage and coalescence taking place in extraction columns is presented. Future parts of this series will be devoted to modelling mass-transfer and sedimentation as well as on application of single-drop based modelling. 相似文献
994.
Mathias Pein Nicole Carina Neumann Luke J. Venstrom Josua Vieten Martin Roeb Christian Sattler 《International Journal of Hydrogen Energy》2021,46(49):24909-24918
Electrolysis and thermochemical water splitting are approaches to produce green hydrogen that use either an electrical potential (electrolysis) or a chemical potential (thermochemical water splitting) to split water. Electrolysis is technologically mature when applied at low temperatures, but it requires large quantities of electrical energy. In contrast to electrolysis, thermochemical water splitting uses thermal energy, as thermal energy can typically be supplied at a lower unit cost than electrical energy using concentrating solar power. Thermochemical water splitting, however, typically suffers from high thermal losses at the extremely high process temperatures required, substantially increasing the total energy required. We show how, by combining electrical and chemical potentials, a novel and cost-efficient water splitting process can be envisioned that overcomes some of the challenges faced by conventional electrolysis and thermochemical water splitting. It uses a mixed ionic and electronic conducting perovskite with temperature-dependent oxygen non-stoichiometry as an anode in an electrolyzer. If solar energy is used as the primary source of all energy required in the process, the cost of the energy required to produce hydrogen could be lower than in high-temperature electrolysis by up to 7%. 相似文献
995.
Se-Ho Kim Joohyun Lim Rajib Sahu Olga Kasian Leigh T. Stephenson Christina Scheu Baptiste Gault 《Advanced materials (Deerfield Beach, Fla.)》2020,32(8):1907235
Molybdenum disulfide (MoS2) nanosheet is a two-dimensional (2D) material with high electron mobility and with high potential for applications in catalysis and electronics. MoS2 nanosheets are synthesized using a one-pot wet-chemical synthesis route with and without Re doping. Atom probe tomography reveals that 3.8 at% Re is homogeneously distributed within the Re-doped sheets. Other impurities are also found integrated within the material: light elements including C, N, O, and Na, locally enriched up to 0.1 at%, as well as heavy elements such as V and W. Analysis of the nondoped sample reveals that the W and V likely originate from the Mo precursor. It is shown how wet-chemical synthesis results in an uncontrolled integration of species from the solution that can affect the material's activity. The results of this work are expected to contribute to an improved understanding of the relationships linking composition to properties of 2D transition-metal dichalcogenide materials. 相似文献
996.
Nicole Verdile Rolando Pasquariello Tiziana A. L. Brevini Fulvio Gandolfi 《International journal of molecular sciences》2020,21(23)
We previously showed that, according to the frequency and distribution of specific cell types, the rainbow trout (RT) intestinal mucosa can be divided in two regions that form a complex nonlinear three-dimensional (3D) pattern and have a different renewal rate. This work had two aims. First, we investigated whether the unusual distribution of cell populations reflects a similar distribution of functional activities. To this end, we determined the protein expression pattern of three well-defined enterocytes functional markers: peptide transporter 1 (PepT1), sodium–glucose/galactose transporter 1 (SGLT-1), and fatty-acid-binding protein 2 (Fabp2). Second, we characterized the structure of RT intestinal stem-cell (ISC) niche and determined whether the different proliferative is accompanied by a different organization and/or extension of the stem-cell population. We studied the expression and localization of well-characterized mammal ISC markers: LGR5, HOPX, SOX9, NOTCH1, DLL1, and WNT3A. Our results indicate that morphological similarity is associated with similar function only between the first portion of the mid-intestine and the apical part of the complex folds in the second portion. Mammal ISC markers are all expressed in RT, but their localization is completely different, suggesting also substantial functional differences. Lastly, higher renewal rates are supported by a more abundant ISC population. 相似文献
997.
998.
Mookambika RamyaBai Nicole M. Wedick Shobana Shanmugam Kokila Arumugam Lakshmipriya Nagarajan Kavitha Vasudevan Geetha Gunasekaran Gayathri Rajagopal Donna Spiegelman Vasanti Malik Ranjit Mohan Anjana Frank B. Hu Ranjit Unnikrishnan Walter Willett Nagappa Malleshi Marina A. Njelekela Dorothy Gimbi Kamala Krishnaswamy CJK Henry Viswanathan Mohan Vasudevan Sudha 《Journal of food science》2019,84(12):3373-3382
999.
Breno R. Barrioni Sandhra M. de Carvalho Parichart Naruphontjirakul Elizabeth Norris Nicole L. Kelly John V. Hanna Julian R. Jones Marivalda de M. Pereira 《Journal of the American Ceramic Society》2022,105(3):1765-1777
Bioactive glass nanoparticles (BGNPs) can be internalized by cells, allowing the intracellular release of dissolution products with therapeutic benefit. Different therapeutic ions can be incorporated into the glass network that can promote angiogenesis via simulation of hypoxia conditions and consequent activation of pro-angiogenic genes. Here, novel monodispersed spherical dense BGNPs were obtained by a modified Stöber method with the SiO2–CaO–CoO composition, with diameters of 92 ± 1 nm, with cobalt as the pro-angiogenic ion. The presence of Co2+ species and the role of Co and Ca as network modifiers in the silica glass were confirmed by X-ray photoelectron spectroscopy and 29Si solid-state magic-angle spinning nuclear magnetic resonance, respectively. Controlled Co2+ ion release was observed in culture media, and no cytotoxicity was observed by (4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide cell viability assay on human osteosarcoma cells in direct contact with the nanoparticles. This study demonstrated that Co2+ ions can be incorporated into dense and spherical BGNPs, and these materials exhibit great potential as intracellular ion delivery systems with therapeutic properties. 相似文献
1000.