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111.
Amaia Garcia-Pena Jaime Ibarrola Adela Navarro Alba Sadaba Carolina Tiraplegui Mattie Garaikoetxea Vanessa Arrieta Lara Matilla Amaya Fernndez-Celis Rafael Sadaba Virginia Alvarez Alicia Gainza Eva Jover Natalia Lpez-Andrs 《International journal of molecular sciences》2021,22(5)
Mitral valve disease (MVD) is a frequent cause of heart failure and death worldwide, but its etiopathogenesis is not fully understood. Interleukin (IL)-33 regulates inflammation and thrombosis in the vascular endothelium and may play a role in the atherosclerotic process, but its role in mitral valve has not been investigated. We aim to explore IL-33 as a possible inductor of myxomatous degeneration in human mitral valves. We enrolled 103 patients suffering from severe mitral regurgitation due to myxomatous degeneration undergoing mitral valve replacement. Immunohistochemistry of the resected leaflets showed IL-33 and ST2 expression in both valve interstitial cells (VICs) and valve endothelial cells (VECs). Positive correlations were found between the levels of IL-33 and molecules implicated in the development of myxomatous MVD, such as proteoglycans, extracellular matrix remodeling enzymes (matrix metalloproteinases and their tissue inhibitors), inflammatory and fibrotic markers. Stimulation of single cell cultures of VICs and VECs with recombinant human IL-33 induced the expression of activated VIC markers, endothelial–mesenchymal transition of VECs, proteoglycan synthesis, inflammatory molecules and extracellular matrix turnover. Our findings suggest that the IL-33/ST2 system may be involved in the development of myxomatous MVD by enhancing extracellular matrix remodeling. 相似文献
112.
Alba Arratibel Alfredo Pacheco Tanaka Martin van Sint Annaland Fausto Gallucci 《International Journal of Hydrogen Energy》2021,46(38):20240-20244
This communication summarizes the use of double-skinned membranes for hydrogen separation in presence of TiO2 based catalyst (PtReCe/TiO2). The use of this type of membrane avoids the direct contact between catalyst particles and surface of the Pd-based hydrogen selective layer due to the presence of a mesoporous YSZ/γ-Al2O3 layer. The PdAg layer is protected by the mesoporous layer from direct contact with catalyst particles, avoiding erosion and possible chemical interactions. In comparison with a conventional PdAg membrane, the hydrogen flux of DS-membrane was observed not to be compromised during test carried out at 400 °C. 相似文献
113.
Nabeel Muhammad Alba Michelia Karasev Andrey Jönsson Pär G. Dogan Neslihan 《Metallurgical and Materials Transactions B》2019,50(4):1674-1685
Metallurgical and Materials Transactions B - Samples taken from laboratory-produced 3rd generation advanced high-strength steels, solidified at a low cooling rate, have been investigated to study... 相似文献
114.
Barquin Gil J. San Roman T.G. Alba Rios J.J. Sanchez Martin P. 《Power Systems, IEEE Transactions on》2000,15(2):483-489
A new electrical sector regulation is being implemented in different countries all over the world. The new regulation stresses the role of competitive markets for the procurement and remuneration of ancillary services. Among these services stand the ones associated with reactive power supply and transmission network voltage control in order to maintain the required system security levels. The object of this paper is twofold. On one hand, reactive power supply and voltage control services, which today are bundled, are decomposed in two types: (i) voltage profile management and reactive dispatch, and (ii) voltage regulation. A theoretical approach based on marginal pricing is proposed in order to clarify the principles to remunerate the suppliers and to charge the consumers of these services. On the other hand, a practical organization of reactive supply and voltage service markets is presented to be implemented in a competitive environment 相似文献
115.
116.
Antonio A. Melo Neto Maria Alba Cincotto Wellington Repette 《Cement and Concrete Composites》2010,32(4):312-318
This article reports the characteristics of blast furnace slag (BFS) pastes activated with hydrated lime (5%) and hydrated lime (2%) plus gypsum (6%) in relation to compressive strength, shrinkage (autogenous and drying) and microstructure (porosity, hydrated products). The paste mixtures were characterized using powder X-ray diffraction (XRD), mercury intrusion porosimetry (MIP) and thermogravimetric analysis (TG/DTG). BSF activated with lime and gypsum (LG) results in larger amounts of ettringite when compared with BFS activated with lime (L). Although the porosities of the L and LG mixtures were about the same, there was a greater pore refinement for the BFS activated with lime, with an increase in mesopores volume with age. The presence of ettringite and the higher volumes of macropores cause the compressive strength of BSF activated with hydrated lime plus gypsum to be smaller than that of BFS activated with lime. For both chemical activators, compressive strength developed slowly at early ages. Autogenous and drying shrinkage were greater for the BFS activated with lime, believed to result from the more refined porous structure in comparison with the mixture activated with gypsum plus lime. 相似文献
117.
Dr. Rob Hoen Dr. Eva Maria Novoa Alba López Noelia Camacho Dr. Laia Cubells Pedro Vieira Prof. Manuel Santos Patricia Marin‐Garcia Prof. Jose Maria Bautista Prof. Alfred Cortés Prof. Lluís Ribas de Pouplana Dr. Miriam Royo 《Chembiochem : a European journal of chemical biology》2013,14(4):499-509
The resistance of malaria parasites to available drugs continues to grow, and this makes the need for new antimalarial therapies pressing. Aminoacyl‐tRNA synthetases (ARSs) are essential enzymes and well‐established antibacterial targets and so constitute a promising set of targets for the development of new antimalarials. Despite their potential as drug targets, apicoplastic ARSs remain unexplored. We have characterized the lysylation system of Plasmodium falciparum, and designed, synthesized, and tested a set of inhibitors based on the structure of the natural substrate intermediate: lysyl‐adenylate. Here we demonstrate that selective inhibition of apicoplastic ARSs is feasible and describe new compounds that that specifically inhibit Plasmodium apicoplastic lysyl‐tRNA synthetase and show antimalarial activities in the micromolar range. 相似文献
118.
J. García-Nieto J. Toutouh E. Alba 《Engineering Applications of Artificial Intelligence》2010,23(5):795-805
The emerging field of vehicular ad hoc networks (VANETs) deals with a set of communicating vehicles which are able to spontaneously interconnect without any pre-existing infrastructure. In such kind of networks, it is crucial to make an optimal configuration of the communication protocols previously to the final network deployment. This way, a human designer can obtain an optimal QoS of the network beforehand. The problem we consider in this work lies in configuring the File Transfer protocol Configuration (FTC) with the aim of optimizing the transmission time, the number of lost packets, and the amount of data transferred in realistic VANET scenarios. We face the FTC with five representative state-of-the-art optimization techniques and compare their performance. These algorithms are: Particle Swarm Optimization (PSO), Differential Evolution (DE), Genetic Algorithm (GA), Evolutionary Strategy (ES), and Simulated Annealing (SA). For our tests, two typical environment instances of VANETs for Urban and Highway scenarios have been defined. The experiments using ns- 2 (a well-known realistic VANET simulator) reveal that PSO outperforms all the compared algorithms for both studied VANET instances. 相似文献
119.
Alfonso Alba Author Vitae José L. Marroquín Author Vitae Author Vitae Thalía Harmony Author Vitae 《Pattern recognition》2010,43(2):530-544
This paper presents a novel methodology for the exploratory analysis of power and synchronization patterns in EEG data from psychophysiological experiments. The methodology is based on the segmentation of the time-frequency plane in regions with relatively homogeneous synchronization patterns, which is performed by means of a seeded region-growing algorithm, and a Bayesian regularization procedure. We have implemented these methods in an interactive application for the study of cognitive experiments, although some of the techniques discussed in this work can also be applied to other multidimensional data sets. To demonstrate our methodology, results corresponding to a figure and word categorization EEG experiment are presented. 相似文献
120.
Anna Castell-Auví M. José Motilva Alba Macià Helena Torrell Cinta Bladé Montserrat Pinent Lluís Arola Anna Ardévol 《Food chemistry》2010
Natural plant extracts are complex mixtures of molecules that have to be uptaken and metabolized, at least by the intestinal barrier, before they reach their body targets. This paper evaluates the feasibility of using a co-culture system to assay the bioactivity of plant extract on hepatic cells closest to the in vivo situation. Caco-2 cells, mimicking intestinal barrier roles, were grown on inserts on a monolayer of HepG2 hepatocytes for 24 h. The co-culture induced some adaptations, but the Caco-2 cells showed no differences in their abilities to filter and metabolize grape-seed derived extract (GSPE) components. The co-culture clearly reproduced the ability of a procyanidin extract to decrease the triglyceride secretion of hepatocytes, a proven in vivo effect. This system mimics a human physiological system that is useful for assaying the bioactivity of extracts and may be able to be used for developing new functional foods. 相似文献