Search results for "Stre"
showing 10 items of 10887 documents
Aplidin® induces JNK-dependent apoptosis in human breast cancer cells via alteration of glutathione homeostasis, Rac1 GTPase activation, and MKP-1 ph…
2006
Aplidin® is an antitumor agent in phase II clinical trials that induces apoptosis through the sustained activation of Jun N-terminal kinase (JNK). We report that Aplidin® alters glutathione homeostasis increasing the ratio of oxidized to reduced forms (GSSG/GSH). Aplidin® generates reactive oxygen species and disrupts the mitochondrial membrane potential. Exogenous GSH inhibits these effects and also JNK activation and cell death. We found two mechanisms by which Aplidin® activates JNK: rapid activation of Rac1 small GTPase and downregulation of MKP-1 phosphatase. Rac1 activation was diminished by GSH and enhanced by L-buthionine (SR)-sulfoximine, which inhibits GSH synthesis. Downregulatio…
Physical inactivity increases oxidative stress, endothelial dysfunction, and atherosclerosis.
2005
Objective— Sedentary lifestyle is associated with increased cardiovascular events. The underlying molecular mechanisms are incompletely understood. Reactive oxygen species (ROS) contribute to endothelial dysfunction and atherosclerosis. An important source of vascular ROS is the NADPH oxidase. Methods and Results— C57BL6 mice were subjected to regular housing (physical inactivity) or voluntary training on running wheels (6 weeks). Inactivity increased vascular lipid peroxidation to 148±9% and upregulated superoxide release to 176±17% (L-012 chemiluminescence) and 188±29% (cytochrome C reduction assay), respectively. ROS production was predominantly increased in the endothelium and the medi…
Razzismo istituzionale e razzismo di strada
2020
Il saggio intende dimostrare il nesso tra razzismo istituzionale e razzismo di strada. The essay intends to demonstrate the link between institutional racism and street racism.
Radio and infrared interferometry of stellar and substellar objects
2020
En el trabajo presentado aquí hemos usado la interferometría a modo de navaja suiza, lo cual nos ha permitido hacer contribuciones relevantes a diversos campos donde una gran resolución angular proporciona una gran ventaja. Hemos estudiado tanto objetos estelares como sub-estelares: desde gigantes rojas con atmósferas muy extensas y frías hasta enanas ultra-frías con una actividad magnética extrema. Todo gracias a la gran resolución que proporcionan los instrumentos actuales, tanto en radio como en infrarrojo, junto con su gran sensibilidad. In the work presented here, we have used interferometry as a Swiss knife allowing us to make contributions in a number of relevant astrophysical scenar…
Radio emission of binary stars in the AB Doradus moving group
2016
We present a study of the radio emission and kinematics of a sample of stars belonging to the AB Doradus moving group through VLA and VLBI observations. The main aim of our study is to obtain precise estimates of the dynamical mass of young, low-mass stars, which in combination with photometric measurements provide precise benchmarks for calibrating pre-main-sequence (PMS) stellar evolutionary models. Calibration of PMS models appears essential as they are widely used to predict the masses of low mass objects as brown dwarfs and planets. Previous studies show that model predictions are in disagreement with experimental results for masses below 1.2 solar masses. Among the stars included in o…
Encuentro de saberes: Huellas de memoria pluriversa y descolonización de la Universidad contemporánea
2018
This paper studies the Encounter of Knowledge as a project that, by welcoming mestres and mestras of ancestral knowledge into universities, contributes to decolonize higher education, broadening its field of memory. Based on a systematization exercise, we established a theoretical dialogue with Bajtin and Bejamin. Based on the participation of four mestres -Lucely Pío, raicera del Cerrado, Mãe Lu and Tata Mutá Imé, religious leaders of Candomblé and the political leader and shaman Álvaro Tukano of the Tukano nation- we show how the project promotes in the contemporary Brazilian university a space of mnemic pluriversity, capable of activating diverse narrative planes (biographical, political…
Earth Bricks with Halloysite Nanoclay: Research and Experimentation for the Sustainability of Materials
2021
The paper illustrates the experimentation activities on rammed earth and nanotechnologies conducted by the authors. The experimental research was carried out with the aim of improving the performance of rammed earth bricks with clay nanotubes, creating a ‘new material’ with reduced embodied energy and low CO2 emissions into the atmosphere. Specifically, the analysed performances are related to the compressive strength that expand their area of use as a building material.
Exploring early adolescents’ stressful IT use experiences
2022
Early adolescents are accustomed to using information technology (IT) for different purposes as a part of their everyday life. While IT use can provide many benefits, it can also include negative experiences, such as feelings of stress (i.e. technostress). Considering that young IT users’ technostress perspectives have remained limited in the literature, this paper attempts to contrast their experiences with aspects from earlier research. A qualitative content analysis of semi-structured interviews with 31 primary and secondary school students reveals that early adolescents have encountered stressful IT use experiences that vary based on the degree of stress. The experiences relate to diffe…
Medial Gastrocnemius Muscle Architecture Is Altered After Exhaustive Stretch-Shortening Cycle Exercise
2019
Muscle architecture is an important component of muscle function, and recent studies have shown changes in muscle architecture with fatigue. The stretch-shortening cycle is a natural way to study human locomotion, but little is known about how muscle architecture is affected by this type of exercise. This study investigated potential changes in medial gastrocnemius (MG) muscle architecture after exhaustive stretch-shortening cycle exercise. Male athletes (n = 10) performed maximal voluntary contractions (MVC) and maximal drop jump (DJ) tests before and after an exercise task consisting of 100 maximal DJs followed by successive rebound jumping to 70% of the initial maximal height. The exerci…