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351.
Cyanidin-3-glucoside (C3G) and cyanidin-3-rutinoside (C3R) are 2 major anthocyanins found in Korean Rubus fruits (blackberries, raspberries, and black raspberries). The antioxidant and antiinflammatory effects of C3G and C3R in RAW264.7 murine macrophage cells were determined. Anthocyanins (5, 10, and 20 μg/mL) significantly (p<0.05) reduced H2O2-induced cytotoxicity in H2O2-stimulated RAW264.7 cells, compared with control cells. Incubation with C3G or C3R significantly (p<0.05) decreased intracellular reactive oxygen species and DNA damage (Hoechst and comet assay), and the cellular ferric reducing antioxidant power also increased, compared with control cells. Nitric oxide production in LPS-stimulated RAW264.7 cells treated with C3G and C3R was reduced by 41.9 and 34.4%, respectively. In addition, LPS-induced prostaglandin E2 production was significantly (p<0.05) inhibited by C3G (51.7%) and C3R (58.6%), compared with LPS-stimulated control cells. Protein expressions of iNOS and COX-2 decreased in cells treated with anthocyanins. Anthocyanins down-regulated NF-κB expression and up-regulated I-κB expression in LPS-treated macrophages. 相似文献
352.
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354.
Hoon Sik Choi Young Shin Ko Hana Jin Ki Mun Kang In Bong Ha Hojin Jeong Jeong-hee Lee Bae Kwon Jeong Hye Jung Kim 《International journal of molecular sciences》2022,23(24)
Breast cancer is the most commonly diagnosed cancer worldwide and ranks first in terms of both prevalence and cancer-related mortality in women. In this study, we aimed to evaluate the anticancer effect of mebendazole (MBZ) and radiotherapy (RT) concomitant use in triple-negative breast cancer (TNBC) cells and elucidate the underlying mechanisms of action. Breast cancer mouse models and several types of breast cancer cells, including TNBC-derived RT-resistant (RT-R) MDA-MB-231 cells, were treated with MBZ and/or RT. In mice, changes in body weight, renal and liver toxicity, tumor volume, and number of lung metastases were determined. In cells, cell viability, colony formation, scratch wound healing, Matrigel invasion, and protein expression using western blotting were determined. Our findings showed that MBZ and RT combined treatment increased the anticancer effect of RT without additional toxicity. In addition, we noted that cyclin B1, PH2AX, and natural killer (NK) cell-mediated cytotoxicity increased following MBZ + RT treatment compared to unaided RT. Our results suggest that MBZ + RT have an enhanced anticancer effect in TNBC which acquires radiation resistance through blocking cell cycle progression, initiating DNA double-strand breaks, and promoting NK cell-mediated cytotoxicity. 相似文献
355.
Lukáš Zdražil Zdeněk Baďura Michal Langer Sergii Kalytchuk David Panáček Magdalena Scheibe Štěpán Kment Hana Kmentová Muhammed Arshad Thottappali Elmira Mohammadi Miroslav Medveď Aristides Bakandritsos Giorgio Zoppellaro Radek Zbořil Michal Otyepka 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(32):2370251
Photoactivation of aspartic acid-based carbon dots (Asp-CDs) induces the generation of spin-separated species, including electron/hole (e−/h+) polarons and spin-coupled triplet states, as uniquely confirmed by the light-induced electron paramagnetic resonance spectroscopy. The relative population of the e−/h+ pairs and triplet species depends on the solvent polarity, featuring a substantial stabilization of the triplet state in a non-polar environment (benzene). The electronic properties of the photoexcited Asp-CDs emerge from their spatial organization being interpreted as multi-layer assemblies containing a hydrophobic carbonaceous core and a hydrophilic oxygen and nitrogen functionalized surface. The system properties are dissected theoretically by density functional theory in combination with molecular dynamics simulations on quasi-spherical assemblies of size-variant flakelike model systems, revealing the importance of size dependence and interlayer effects. The formation of the spin-separated states in Asp-CDs enables the photoproduction of hydrogen peroxide (H2O2) from water and water/2-propanol mixture via a water oxidation reaction. 相似文献
356.
Magnetic Resonance Materials in Physics, Biology and Medicine - Exploring mouse brains by rapid 3D-Diffusion Tensor Imaging (3D-DTI) of high spatial resolution (HSR) is challenging in vivo. Here we... 相似文献
357.
Klára Papoušková Marcos Gómez Marie Kodedová José Ramos Olga Zimmermannová Hana Sychrová 《Yeast (Chichester, England)》2023,40(2):68-83
In the model yeast Saccharomyces cerevisiae, Trk1 is the main K+ importer. It is involved in many important physiological processes, such as the maintenance of ion homeostasis, cell volume, intracellular pH, and plasma-membrane potential. The ScTrk1 protein can be of great interest to industry, as it was shown that changes in its activity influence ethanol production and tolerance in S. cerevisiae and also cell performance in the presence of organic acids or high ammonium under low K+ conditions. Nonconventional yeast species are attracting attention due to their unique properties and as a potential source of genes that encode proteins with unusual characteristics. In this work, we aimed to study and compare Trk proteins from Debaryomyces hansenii, Hortaea werneckii, Kluyveromyces marxianus, and Yarrowia lipolytica, four biotechnologically relevant yeasts that tolerate various extreme environments. Heterologous expression in S. cerevisiae cells lacking the endogenous Trk importers revealed differences in the studied Trk proteins' abilities to support the growth of cells under various cultivation conditions such as low K+ or the presence of toxic cations, to reduce plasma-membrane potential or to take up Rb+. Examination of the potential of Trks to support the stress resistance of S. cerevisiae wild-type strains showed that Y. lipolytica Trk1 is a promising tool for improving cell tolerance to both low K+ and high salt and that the overproduction of S. cerevisiae's own Trk1 was the most efficient at improving the growth of cells in the presence of highly toxic Li+ ions. 相似文献
358.
Petra Mnov Frantiek Kafka Hana Dvokov Smita Gunnoo Miloslav anda Radek Cibulka 《Advanced Synthesis \u0026amp; Catalysis》2011,353(6):865-870
A series of 3‐substituted pyrazinium tetrafluoroborates was prepared as simple analogues of flavinium salts which are efficient organocatalysts for oxidations with hydrogen peroxide. It was shown that pyrazinium derivatives with an electron‐withdrawing substituent catalyze mild oxidations of sulfides to sulfoxides and Baeyer–Villiger oxidations in a similar way to flavinium catalysts. The most reactive catalyst, 3‐cyanopyrazinium tetrafluoroborate, was efficiently employed in preparative sulfoxidations of aromatic and aliphatic sulfides as well as in Baeyer–Villiger oxidations of cyclobutanones. A proposed mechanism for the catalysis is based on the formation of pyrazine hydroperoxide which is the agent oxidizing the substrate. 相似文献
359.
Sierra J. Williams Jordan A. Gewing-Mullins Whitney K. Lieberman Bethany Kolbaba-Kartchner Reema Iqbal Hana M. Burgess Clair M. Colee Marya Y. Ornelas Edison S. Reid-McLaughlin Prof. Dr. Jeremy H. Mills Prof. Dr. Jennifer A. Prescher Prof. Dr. Aaron M. Leconte 《Chembiochem : a European journal of chemical biology》2023,24(6):e202200726
Engineered luciferase-luciferin pairs have expanded the number of cellular targets that can be visualized in tandem. While light production relies on selective processing of synthetic luciferins by mutant luciferases, little is known about the origin of selectivity. The development of new and improved pairs requires a better understanding of the structure−function relationship of bioluminescent probes. In this work, we report a biochemical approach to assessing and optimizing two popular bioluminescent pairs: Cashew/d -luc and Pecan/4′-BrLuc. Single mutants derived from Cashew and Pecan revealed key residues for selectivity and thermal stability. Stability was further improved through a rational addition of beneficial residues. In addition to providing increased stability, the known stabilizing mutations surprisingly also improved selectivity. The resultant improved pair of luciferases are >100-fold selective for their respective substrates and highly thermally stable. Collectively, this work highlights the importance of mechanistic insight for improving bioluminescent pairs and provides significantly improved Cashew and Pecan enzymes which should be immediately suitable for multicomponent imaging applications. 相似文献