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Graziamaria Corbi Andrea Bianco Viviana Turchiarelli Michele Cellurale Federica Fatica Aurora Daniele Gennaro Mazzarella Nicola Ferrara 《International journal of molecular sciences》2013,14(6):12696-12713
The development of atherosclerosis is a multi-step process, at least in part controlled by the vascular endothelium function. Observations in humans and experimental models of atherosclerosis have identified monocyte recruitment as an early event in atherogenesis. Chronic inflammation is associated with ageing and its related diseases (e.g., atherosclerosis and chronic obstructive pulmonary disease). Recently it has been discovered that Sirtuins (NAD+-dependent deacetylases) represent a pivotal regulator of longevity and health. They appear to have a prominent role in vascular biology and regulate aspects of age-dependent atherosclerosis. Many studies demonstrate that SIRT1 exhibits anti-inflammatory properties in vitro (e.g., fatty acid-induced inflammation), in vivo (e.g., atherosclerosis, sustainment of normal immune function in knock-out mice) and in clinical studies (e.g., patients with chronic obstructive pulmonary disease). Because of a significant reduction of SIRT1 in rodent lungs exposed to cigarette smoke and in lungs of patients with chronic obstructive pulmonary disease (COPD), activation of SIRT1 may be a potential target for chronic obstructive pulmonary disease therapy. We review the inflammatory mechanisms involved in COPD-CVD coexistence and the potential role of SIRT1 in the regulation of these systems. 相似文献
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Hou Kaiming Bavisotto Robert Manzi Sergio Javier Perez Eliseo Joaquín Furlong Octavio Javier Kotvis Peter Kenmoe Germaine Djuidje Tysoe Wilfred T. 《Tribology Letters》2022,70(2):1-19
Tribology Letters - Most asteroids with a diameter larger than $$sim 300 {mathrm{m}}$$ are rubble piles, i.e., consisting of more than one solid object. All asteroids are rotating but almost... 相似文献
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Aurora Araiza-Campos Dr. Guillermo Herrera-Pérez Dr. Joan S. Salas-Leiva Margarita Chávez-Beltrán de Río Alejandro Aguirre-Hernández Dr. Antonia Luna-Velasco Dr. Dayana Salas-Leiva Eduardo Campos-Chávez Dr. Dariel Tovar-Ramírez Alejandro Romo-Chacón Dr. Erasmo Orrantia-Borunda Dr. Francisco Paraguay-Delgado 《Chembiochem : a European journal of chemical biology》2023,24(22):e202300542
The current study compares the antibacterial activity of zinc oxide nanostructures (neZnO). For this purpose, two bacterial strains, Escherichia coli (ATCC 4157) and Staphylococcus aureus (ATCC 29213) were challenged in room light conditions with the aforementioned materials. Colloidal and hydrothermal methods were used to obtain the quasi-round and quasi-diamond platelet-shape nanostructures. Thus, the oxygen vacancy (VO) effects on the surface of neZnO are also considered to assess its effects on antibacterial activity. The neZnO characterization was achieved by X-ray diffraction (XRD), a selected area electron diffraction (SAED) and Raman spectroscopy. The microstructural effects were monitored by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Furthermore, optical absorption ultraviolet visible spectrophotometry (UV-Vis) and X-ray photoelectron spectroscopy (XPS) analyses complement the physical characterization of these nanostructures; neZnO caused 50 % inhibition (IC50) at concentrations from 0.064 to 0.072 mg/mL for S. aureus and from 0.083 to 0.104 mg/mL for E. coli, indicating an increase in activity against S. aureus compared to E. coli. Consequently, quasi-diamond platelet-shaped nanostructures (average particle size of 377.6±10 nm) showed enhanced antibacterial activity compared to quasi-round agglomerated particles (average size of 442.8±12 nm), regardless of Vo presence or absence. 相似文献
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Lourdes Prez Aurora Pinazo M. C. Morn Ramon Pons 《International journal of molecular sciences》2020,21(23)
The surface activity, aggregates morphology, size and charge characteristics of binary catanionic mixtures containing a cationic amino acid-derived surfactant N(π), N(τ)-bis(methyl)-L-Histidine tetradecyl amide (DMHNHC14) and an anionic surfactant (the lysine-based surfactant Nα-lauroyl-Nεacetyl lysine (C12C3L) or sodium myristate) were investigated for the first time. The cationic surfactant has an acid proton which shows a strong pKa shift irrespective of aggregation. The resulting catanionic mixtures exhibited high surface activity and low critical aggregation concentration as compared with the pure constituents. Catanionic vesicles based on DMHNHC14/sodium myristate showed a monodisperse population of medium-size aggregates and good storage stability. According to Small-Angle X-Ray Scattering (SAXS), the characteristics of the bilayers did not depend strongly on the system composition for the positively charged vesicles. Negatively charged vesicles (cationic surfactant:myristate ratio below 1:2) had similar bilayer composition but tended to aggregate. The DMHNHC14-rich vesicles exhibited good antibacterial activity against Gram-positive bacteria and their bactericidal effectivity declined with the decrease of the cationic surfactant content in the mixtures. The hemolytic activity and cytotoxicity of these catanionic formulations against non-tumoral (3T3, HaCaT) and tumoral (HeLa, A431) cell lines also improved by increasing the ratio of cationic surfactant in the mixture. These results indicate that the biological activity of these systems is mainly governed by the cationic charge density, which can be modulated by changing the cationic/anionic surfactant ratio in the mixtures. Remarkably, the incorporation of cholesterol in those catanionic vesicles reduces their cytotoxicity and increases the safety of future biomedical applications of these systems. 相似文献
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In the past transhumance of sheep was an important phenomenon which took place all over the territories of central and southern Italy. The flocks, which in summer were pastured in the mountains of the central Apennines, in winter were moved across an intricate network of tracks (called ‘Tratturi’ in Italian) to the lowlands of the Adriatic cost and the plains of Puglia. As a result of a crisis this type of sheep-rearing is disappearing as well as the characteristics of the landscape which resulted from these journeys. We examine what remains of the characteristics of the landscape and vegetation of the ‘Bosco dell'Incoronata’ one of the last winter pastures of Puglia. 相似文献
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Kouskoulas Yanni Machado T. J. Genin Daniel Schmidt Aurora Papusha Ivan Brul Joshua 《International Journal on Software Tools for Technology Transfer (STTT)》2022,24(3):371-394
International Journal on Software Tools for Technology Transfer - We present an approach to analyze the safety of asynchronous, independent, non-deterministic, turn-to-bearing horizontal maneuvers... 相似文献
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Aurora Barrero Xabiel G. Pañeda Roberto García Laura Pozueco 《International journal of human-computer interaction》2016,32(10):765-776
The popularity of Interactive Digital Television (IDTV) applications has grown in recent years, playing a significant role in today’s society. This new type of television allows users to access interactive applications in order to look for information, for communication or educational purposes, or just for fun. Most of these applications require text entry and many users expect a user experience similar to that of computers. Although the most common device to interact with television is the conventional remote control, other devices available on the market may be used in this context. Thus, in this article we aim to evaluate and compare different text input methods for IDTV applications using devices alternative to conventional remote controls. We have carried out an empirical study with 52 participants. We analyze entry speeds, error rates, and subjective impressions for six different entry methods, taking into account the particular characteristics of the users. As devices we have used a full-sized keyboard, a palm-sized keyboard, a gyroscopic remote point-select, and a modified touchpad. The fastest method is the standard keyboard, but in an IDTV context many users report discomfort and problems under low lighting conditions. Also, error rates are considerably higher with both keyboards when modifier keys need to be used. The results obtained with the gyroscopic remote and the touchpad are similar. Nevertheless, while users complain about fatigue problems with the former, their feedback about the latter is very positive. We have also observed that age is a major factor affecting the performance of the users. We expect our results to contribute to the design of new text entry methods for IDTV. 相似文献