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271.
Muhammed Ashiq Thalappil Elena Butturini Alessandra Carcereri de Prati Ilaria Bettin Lorenzo Antonini Filippo Umberto Sapienza Stefania Garzoli Rino Ragno Sofia Mariotto 《Molecules (Basel, Switzerland)》2022,27(15)
Essential oils (EOs) and their components have been reported to possess anticancer properties and to increase the sensitivity of cancer cells to chemotherapy. The aim of this work was to select EOs able to downregulate STAT3 signaling using Western blot and RT-PCR analyses. The molecular mechanism of anti-STAT3 activity was evaluated through spectrophotometric and fluorometric analyses, and the biological effect of STAT3 inhibition was analyzed by flow cytometry and wound healing assay. Herein, Pinus mugo EO (PMEO) is identified as an inhibitor of constitutive STAT3 phosphorylation in human prostate cancer cells, DU145. The down-modulation of the STAT3 signaling cascade decreased the expression of anti-proliferative as well as anti-apoptotic genes and proteins, leading to the inhibition of cell migration and apoptotic cell death. PMEO treatment induced a rapid drop in glutathione (GSH) levels and an increase in reactive oxygen species (ROS) concentration, resulting in mild oxidative stress. Pretreatment of cells with N-acetyl-cysteine (NAC), a cell-permeable ROS scavenger, reverted the inhibitory action of PMEO on STAT3 phosphorylation. Moreover, combination therapy revealed that PMEO treatment displayed synergism with cisplatin in inducing the cytotoxic effect. Overall, our data highlight the importance of STAT3 signaling in PMEO cytotoxic activity, as well as the possibility of developing adjuvant therapy or sensitizing cancer cells to conventional chemotherapy. 相似文献
272.
Margherita De Rosa Stefania Gambaro Annunziata Soriente Paolo Della Sala Veronica Iuliano Carmen Talotta Carmine Gaeta Antonio Rescifina Placido Neri 《Chemical science》2022,13(29):8618
Carbocation catalysis can be performed inside the confined space of the hexameric resorcinarene capsule. The inner cavity of the capsule can host the trityl carbocation, which catalyses the Diels–Alder reaction between dienes and unsaturated aldehydes. Experimental results and in silico calculations show that the hexameric resorcinarene capsule C6 can promote the formation of the trityl carbocation from trityl chloride through the cleavage of the carbon–halogen bond promoted by OH⋯X− hydrogen bonding. Here it is shown that the combination of the nanoconfined space and the latent carbocation catalysis provides a convenient complementary strategy for the typical carbocation catalysis. The latent strategy bypasses the typical pitfalls associated with active carbocations and provides control of the reaction efficiency in terms of reaction rate, conversion, and selectivity.The hexameric resorcinarene capsule is able to promote carbocation catalysis inside its cavity. 相似文献
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In this paper we describe an experiment whose goal is to investigate the role of the footstep sounds and soundscapes to affect the pace of a person walking in place (mimicking the act of walking without leaving the current position). Subjects were exposed to different simulated footstep sounds and soundscapes, generated in realtime while walking in place. The results show that, indeed, participants adapted their walking pace to the presented sounds, and not only footstep sounds but also soundscapes affect the walking pace. We could observe as well that perceived ease of walking correlates with the perceived naturalness of ambient sounds. 相似文献
275.
Maria Gregori Daniela Bertani Emanuela Cazzaniga Antonina Orlando Michele Mauri Alberto Bianchi Francesca Re Silvia Sesana Stefania Minniti Maura Francolini Alfredo Cagnotto Mario Salmona Luca Nardo Domenico Salerno Francesco Mantegazza Massimo Masserini Roberto Simonutti 《Macromolecular bioscience》2015,15(12):1687-1697
276.
Giuliana Borsa Stefania Castelletto Aldo Godone Carlo Novero Maria Luisa Rastello 《Optical Review》1997,4(4):484-489
This work presents a new technique for the measurement of second-order optical nonlinear coefficients from the absolute radiant power of the parametric fluorescence emission. It is based on calibrated detectors regarded as secondary radiometric standards. This technique makes it possible to skip a number of problems usually encountered with standard techniques based on calibrated neutral density filters and reference sources of light at much higher power levels. We infer a value for the d31 nonlinear coefficient of LiIO3 from spectral measurements of the fluorescence power integrated over all solid angles, by denning the wavelength bandwidths with interference filters. Moreover, by performing the measurements on the ultraviolet and visible emission lines of an argon ion laser in the range from 351 to 488 nm, the wavelength dependence of d31 is compared with the expected one obtained by Miller’s dispersion law. 相似文献
277.
The title compound 3 was obtained during the rearrangement of isoxazol-5-yl hydrazine 1 to 1-aminopyrazolone 2 at 115°. X-ray analysis of the corresponding benzylidene derivative allowed us to achieve the structure assignment. 相似文献
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