@article{GonzalezChavarriaDupratRoaetal.2020, author = {Gonzalez-Chavarria, Ivan and Duprat, Felix and Roa, Francisco J. and Jara, Nery and Toledo, Jorge R. and Miranda, Felipe and Becerra, Jose and Inostroza, Alejandro and Kelling, Alexandra and Schilde, Uwe and Heydenreich, Matthias and Paz, Cristian}, title = {Maytenus disticha extract and an isolated β-Dihydroagarofuran induce mitochondrial depolarization and apoptosis in human cancer cells by increasing mitochondrial reactive oxygen species}, series = {Biomolecules}, volume = {10}, journal = {Biomolecules}, number = {3}, publisher = {MDPI}, address = {Basel}, issn = {2218-273X}, doi = {10.3390/biom10030377}, pages = {15}, year = {2020}, abstract = {Maytenus disticha (Hook F.), belonging to the Celastraceae family, is an evergreen shrub, native of the central southern mountains of Chile. Previous studies demonstrated that the total extract of M. disticha (MD) has an acetylcholinesterase inhibitory activity along with growth regulatory and insecticidal activities. beta-Dihydroagarofurans sesquiterpenes are the most active components in the plant. However, its activity in cancer has not been analyzed yet. Here, we demonstrate that MD has a cytotoxic activity on breast (MCF-7), lung (PC9), and prostate (C4-2B) human cancer cells with an IC50 (mu g/mL) of 40, 4.7, and 5 mu g/mL, respectively, an increasing Bax/Bcl2 ratio, and inducing a mitochondrial membrane depolarization. The beta-dihydroagarofuran-type sesquiterpene (MD-6), dihydromyricetin (MD-9), and dihydromyricetin-3-O-beta-glucoside (MD-10) were isolated as the major compounds from MD extracts. From these compounds, only MD-6 showed cytotoxic activity on MCF-7, PC9, and C4-2B with an IC50 of 31.02, 17.58, and 42.19 mu M, respectively. Furthermore, the MD-6 increases cell ROS generation, and MD and MD-6 induce a mitochondrial superoxide generation and apoptosis on MCF-7, PC9, and C4-2B, which suggests that the cytotoxic effect of MD is mediated in part by the beta-dihydroagarofuran-type that induces apoptosis by a mitochondrial dysfunction.}, language = {en} } @article{SocquetValdesJaraetal.2017, author = {Socquet, Anne and Valdes, Jesus Pina and Jara, Jorge and Cotton, Fabrice and Walpersdorf, Andrea and Cotte, Nathalie and von Specht, Sebastian and Ortega-Culaciati, Francisco and Carrizo, Daniel and Norabuena, Edmundo}, title = {An 8month slow slip event triggers progressive nucleation of the 2014 Chile megathrust}, series = {Geophysical research letters}, volume = {44}, journal = {Geophysical research letters}, publisher = {American Geophysical Union}, address = {Washington}, issn = {0094-8276}, doi = {10.1002/2017GL073023}, pages = {4046 -- 4053}, year = {2017}, abstract = {The mechanisms leading to large earthquakes are poorly understood and documented. Here we characterize the long-term precursory phase of the 1 April 2014 M(w)8.1 North Chile megathrust. We show that a group of coastal GPS stations accelerated westward 8months before the main shock, corresponding to a M(w)6.5 slow slip event on the subduction interface, 80\% of which was aseismic. Concurrent interface foreshocks underwent a diminution of their radiation at high frequency, as shown by the temporal evolution of Fourier spectra and residuals with respect to ground motions predicted by recent subduction models. Such ground motions change suggests that in response to the slow sliding of the subduction interface, seismic ruptures are progressively becoming smoother and/or slower. The gradual propagation of seismic ruptures beyond seismic asperities into surrounding metastable areas could explain these observations and might be the precursory mechanism eventually leading to the main shock.}, language = {en} } @article{JaraSanchezReyesSocquetetal.2018, author = {Jara, Jorge and Sanchez-Reyes, Hugo and Socquet, Anne and Cotton, Fabrice and Virieux, Jean and Maksymowicz, Andrei and Diaz-Mojica, John and Walpersdorf, Andrea and Ruiz, Javier and Cotte, Nathalie and Norabuena, Edmundo}, title = {Kinematic study of Iquique 2014 M-w 8.1 earthquake}, series = {Earth \& planetary science letters}, volume = {503}, journal = {Earth \& planetary science letters}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0012-821X}, doi = {10.1016/j.epsl.2018.09.025}, pages = {131 -- 143}, year = {2018}, abstract = {We study the rupture processes of Iquique earthquake M-w 8.1 (2014/04/01) and its largest aftershock M-w 7.7 (2014/04/03) that ruptured the North Chile subduction zone. High-rate Global Positioning System (GPS) recordings and strong motion data are used to reconstruct the evolution of the slip amplitude, rise time and rupture time of both earthquakes. A two-step inversion scheme is assumed, by first building prior models for both earthquakes from the inversion of the estimated static displacements and then, kinematic inversions in the frequency domain are carried out taken into account this prior information. The preferred model for the mainshock exhibits a seismic moment of 1.73 x 10(21) Nm (M-w 8.1) and maximum slip of similar to 9 m, while the aftershock model has a seismic moment of 3.88 x 10(20) (M-w 7.7) and a maximum slip of similar to 3 m. For both earthquakes, the final slip distributions show two asperities (a shallow one and a deep one) separated by an area with significant slip deficit. This suggests a segmentation along-dip which might be related to a change of the dipping angle of the subducting slab inferred from gravimetric data. Along-strike, the areas where the seismic ruptures stopped seem to be well correlated with geological features observed from geophysical information (high-resolution bathymetry, gravimetry and coupling maps) that are representative of the long-term segmentation of the subduction margin. Considering the spatially limited portions that were broken by these two earthquakes, our results support the idea that the seismic gap is not filled yet. (C) 2018 Elsevier B.V. All rights reserved.}, language = {en} } @misc{JaraSanchezReyesSocquetetal.2018, author = {Jara, Jorge and S{\´a}nchez-Reyes, Hugo and Socquet, Anne and Cotton, Fabrice and Virieux, Jean and Maksymowicz, Andrei and D{\´i}az-Mojica, John and Walpersdorf, Andrea and Ruiz, Javier and Cotte, Nathalie and Norabuena, Edmundo}, title = {Corrigendum to: Kinematic study of Iquique 2014 Mw 8.1 earthquake: Understanding the segmentation of the seismogenic zone. - (Earth and planetary science letters. - 503 (2018) S. 131 - 143)}, series = {Earth and planetary science letters}, volume = {506}, journal = {Earth and planetary science letters}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0012-821X}, doi = {10.1016/j.epsl.2018.11.026}, pages = {347 -- 347}, year = {2018}, abstract = {We study the rupture processes of Iquique earthquake 8.1 (2014/04/01) and its largest aftershock 7.7 (2014/04/03) that ruptured the North Chile subduction zone. High-rate Global Positioning System (GPS) recordings and strong motion data are used to reconstruct the evolution of the slip amplitude, rise time and rupture time of both earthquakes. A two-step inversion scheme is assumed, by first building prior models for both earthquakes from the inversion of the estimated static displacements and then, kinematic inversions in the frequency domain are carried out taken into account this prior information. The preferred model for the mainshock exhibits a seismic moment of 1.73 × 1021 Nm ( 8.1) and maximum slip of ∼9 m, while the aftershock model has a seismic moment of 3.88 × 1020 ( 7.7) and a maximum slip of ∼3 m. For both earthquakes, the final slip distributions show two asperities (a shallow one and a deep one) separated by an area with significant slip deficit. This suggests a segmentation along-dip which might be related to a change of the dipping angle of the subducting slab inferred from gravimetric data. Along-strike, the areas where the seismic ruptures stopped seem to be well correlated with geological features observed from geophysical information (high-resolution bathymetry, gravimetry and coupling maps) that are representative of the long-term segmentation of the subduction margin. Considering the spatially limited portions that were broken by these two earthquakes, our results support the idea that the seismic gap is not filled yet.}, language = {en} }