University of Valencia
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Proteomic Analysis of Saccharomyces cerevisiae Response to Oxidative Stress Mediated by Cocoa Polyphenols Extract
No full textThe present study addressed the protective effects against oxidative stress (OS) of a cocoa powder extract (CPEX) on the protein expression profile of S. cerevisiae. A proteomic analysis was performed after culture preincubation with CPEX either without stress (−OS) or under stress conditions (+OS) (5 mM of H2O2). LC-MS/MS identified 33 differentially expressed proteins (-OS: 14, +OS: 19) that were included By Gene Ontology analysis in biological processes: biosynthesis of amino acids, carbohydrate metabolism and reactive oxygen species metabolic process. In a gene-knockout strains study, eight proteins were identified as putative candidates for being involved in the protective mechanism of cocoa polyphenols against OS induced by H2O2. CPEX was able to exert its antioxidant activity in yeast mainly through the regulation of: (a) amino acids metabolism proteins by modulating the production of molecules with known antioxidant roles; (b) stress-responsive protein Yhb1, but we were unable to fully understand its down-regulation; (c) protein Prb1, which can act by clipping Histone H3 N-terminal tails that are related to cellular resistance to DNA damaging agents
Human dental pulp stem cells differentiate into cementoid-like-secreting cells on decellularized teeth scaffold.
No full textPeriodontitis is a common inflammatory disease that in some cases can cause tooth loss. Cementum is a mineralized tissue that forms part of the insertion periodontium and serves to fix the teeth to the alveolar bone. In addition, it acts as a reservoir of different growth and differentiation factors, which regulate the biology of the teeth. Cementogenesis is a complex process that is still under investigation and involves different factors, including dentin sialophosphoprotein (DSPP). In this work we studied the role of surface microtopography in the differentiation of human dental pulp stem cells (hDPSCs) into cementoid-like secreting cells. We cultured hDPSCs on decellularized dental scaffolds on either dentin or cementum surfaces. Cell morphology was evaluated by light and electron microscopy. We also evaluated the DSPP expression by immunohistochemistry. The hDPSCs that was cultured on surfaces with accessible dentinal tubules acquired an odontoblastic phenotype and emitted characteristic processes within the dentinal tubules. These cells synthesized the matrix components of a characteristic reticular connective tissue, with fine collagen fibers and DSPP deposits. The hDPSCs that was cultured on cementum surfaces generated a well-organized tissue consisting of layers of secretory cells and dense fibrous connective tissue with thick bundles of collagen fibers perpendicular to the scaffold surface. Intra- and intercellular deposits of DSPP were also observed. The results presented here reinforce the potential for hDPSCs to differentiate in vitro into cells that secrete a cementoid-like matrix in response to the physical stimuli related to the microtopography of contact surfaces. We also highlight the role of DSPP as a component of the newly formed matrix
Análisis bibliométrico y sistémico de la relación entre gestión y carbono
No full textThis paper aims to present a bibliometric and systemic analysis of the Bibliographic Portfolio (BP) jointly examining the literature related to topics like 'Greenhouse gas,' mainly carbon, and 'Management,' as published in databases data such as Web of Science and Scopus in the field of economic and social sciences. The Knowledge and Constructivist Development Process methodology ¿Proknow-C¿ was used to establish the final portfolio and through the VosViewer program were mapped the various groups or relationships between the studied literature. The paper presents the theoretical and methodological aspects focusing on the areas and countries of study and highlighting the most relevant authors to have researched this particular topic. We use this constructivist model to describe the measurement variables and synthesize the concepts most used in these studies in order to propose new focal points and thematic approaches that could be developed further in the future
Alternative tuition fees schemes: a simulation exercise
No full textIn this paper we use a theoretical model of effort optimization on the part of university students to simulate the effects of different tuition fees schemes. For each of such schemes, we present and discuss the trade-offs that appear among the three outcomes that every exercise of policy evaluation in this context should take into consideration, namely, efficiency - that is, student effort-, student welfare and university revenues. To this end, we depart from the tuition fees policy change that took place in the Spanish public university system in year 2012 and compare it with alternative tuition fees designs. Among other results we find that a design with very low entry fees and high penalty cost for failing the exams is the most suitable one in terms of efficiency and university revenues
Mangiferin nanoemulsions in treatment of inflammatory disorders and skin regeneration
No full textIn this paper mangiferin nanoemulsions were developed using hyaluronic acid of different molecular weight, in absence or presence of Transcutol-P. An extensive study was carried out on the physico-chemical properties of nanoemulsions. Nanosizer and transmission electron microscopy showed oil droplets average size 296 nm with monodisperses distribution (PI ≤ 0.30). The zeta potential was highly negative (−30 mV). FTIR analysis con- firms the existence of physical interactions among compounds. Rheological measurements allowed to conclude that all formulations present a pseudoplastic behavior (s∼0.4) in presence of the biopolymer. Moreover, mangiferin release depends on the molecular weight of the polymer. Permeability assays on pig epidermis showed that nanoemulsions with low molecular weight hyaluronic acid improve the permeation, being this effect more pronounced in nanoemulsions with Transcutol-P. Administration of mangiferin nanoemulsions on TPA-inflamed skin mice model provided an attenuation of oedema and leucocyte infiltration. Macroscopic ap- pearance of mice skin lesions has a good correlation with the histological study. The topical application of these formulations shows an appropriate anti-inflammatory effect
Therapeutic efficacy of quercetin enzyme-responsive nanovesicles for the treatment of experimental colitis in rats
No full textBiocompatible quercetin nanovesicles were developed by coating polyethylene glycol-containing vesicles with chitosan and nutriose, aimed at targeting the colon. Uncoated and coated vesicles were prepared using hydrogenated soy phosphatidylcholine and quercetin, a potent natural anti-inflammatory and anti- oxidant drug. Physicochemical characterization was carried out by light scattering, cryogenic microscopy and X-ray scattering, the results showing that vesicles were predominantly multilamellar and around 130 nm in size. The in vitro release of quercetin was investigated under different pH conditions simulat- ing the environment of the gastrointestinal tract, and confirmed that the chitosan/nutriose coating improved the gastric resistance of vesicles, making them a potential carrier system for colon delivery. The preferential localization of fluorescent vesicles in the intestine was demonstrated using the In Vivo FX PRO Imaging System. Above all, a marked amelioration of symptoms of 2,4,6-trinitrobenzenesulfonic acid-induced colitis was observed in animals treated with quercetin-loaded coated vesicles, favoring the restoration of physiological conditions. Therefore, quercetin-loaded chitosan/nutriose-coated vesicles can represent a valuable therapeutic tool for the treatment of chronic intestinal inflammatory diseases, and presumably a preventive system, due to the synergic action of antioxidant quercetin and beneficial pre- biotic effects of the chitosan/nutriose complex
Orígenes y desarrollo del periodismo sensacionalista de sucesos en España (1883-1917)
No full textEste trabajo postula la existencia de una prensa de sucesos consolidada e influyente (por su tirada y por la entidad de los cambios periodísticos que introduce) en España durante el período de la Restauración (1874-1923). Es una hipótesis inédita en la historia del periodismo español, que ha marginado en sus síntesis este tipo de prensa especializada y le ha dedicado muy pocas monografías o análisis de caso. Lo cierto es que, desde finales del siglo XIX, algunos editores pusieron en práctica esta forma de atraer la atención y el interés del público, apelando a noticias marcadas por la tragedia, la violencia y la muerte. A través del análisis de los semanarios Las Noticias Ilustradas (1883), Los Sucesos (1904-1917), Las Novedades (1908) y La Semana Ilustrada (1917), se observa la rivalidad creciente en la época en torno al periodismo sensacionalista. Se analiza el rol de editores como Eduardo Sojo, Domingo Blanco Misamigo o la Editorial Estampa para evidenciar las apuestas empresariales que consolidaron la versión española de la prensa de crónica roja, así como las características narrativas empleadas y la emergencia del periodismo gráfico de sucesos.- de atraer la atención y el interés del público, apelando a noticias marcadas por la tragedia y la muerte. A través del análisis de los semanarios Las Noticias Ilustradas (1883), Los Sucesos (1904-1917), Las Novedades (1908) y La Semana Ilustrada (1917), se observa la rivalidad creciente en la época en torno al periodismo sensacionalista. Se analiza el rol de editores como Eduardo Sojo, Domingo Blanco Misamigo o la Editorial Estampa para evidenciar las apuestas empresariales que consolidaron la versión española de la prensa de crónica roja, así como las características narrativas empleadas y la emergencia del periodismo gráfico de sucesos
The Emergence of the Lobsters: Phylogenetic Relationships, Morphological Evolution and Divergence Time Comparisons of a Fossil Rich Group (Decapoda: Achelata, Astacidea, Glypheidea, Polychelida)
No full textThe Emergence of the Lobsters: Phylogenetic Relationships, Morphological Evolution and Divergence Time Comparisons of a Fossil Rich Group (Decapoda: Achelata, Astacidea, Glypheidea, Polychelida
How ethical are managers' goodwill impairment decisions in Spanish-listed firms?
No full textThis paper provides an analysis of the ethical behavior of managers making goodwill impairment decisions following the adoption of the International Financial Reporting Standard (IFRS) 3 on Business Combinations. Replacing the systematic amortization of goodwill with the impairment-only approach has been a highly controversial step. Although the aim of IFRS 3 was to provide users with more value-relevant information regarding the underlying economics of the business, it has been criticized for the potential earnings management inherent in impairment testing. This study is based on a sample of Spanish listed companies between 2005 and 2011, a period that embraces the economic crisis. After controlling for the underlying economic factors of the firms, the results suggest that managers are exercising discretion in the reporting of goodwill impairment losses, and big bath and smoothing strategies are influencing the decisions, whether or not to impair goodwill and about the magnitude of the impairment. Firm size is an attribute that appears significant in the analysis, suggesting that the cost and complexity of running the impairment test affect managers' decisions. Additional analyses suggest that the macroeconomic environment influences opportunistic and unethical behavior
Magneto-structural correlations in asymmetric oxalato-bridged dicopper(II) complexes with polymethyl-substituted pyrazole ligands
No full textTwo oxalato-bridged dinuclear copper(II) complexes, [{Cu(Hdmpz)3}2(μ-ox)](ClO4)2·2H2O (1) and [{Cu(Htmpz)3}2(μ-ox)](ClO4)2·2H2O (2) (Hdmpz = 3,5-dimethyl-1H-pyrazole and Htmpz = 3,4,5-trimethyl-1H-pyrazole), have been synthesized and structurally and magnetically characterized. The crystal structures of 1 and 2 consist of asymmetric bis-bidentate μ-oxalatodicopper(II) complex cations with two short [Cu-O = 1.976(2) (1) and 1.973(2) Å (2)] and two long copper-oxygen bonds [Cu-O = 2.122(2) (1) and 2.110(2) Å (2)]. The environment at each CuII ion in 1 and 2 is closer to the trigonal bipyramidal geometry than to the square pyramidal [τ = 0.633 (1) and 0.711 (2)]. The magnetic properties of 1 and 2 show moderate antiferromagnetic coupling between the CuII ions through the oxalato bridge [J = −129 (1) and 161 cm−1 (2); H = −JS1 · S2 with S1 = S2 = SCu = ½]. A thorough magneto-structural analysis has been carried out for the family of asymmetric μ-oxalatodicopper(II) complexes with different terminal ligands to determine the influence on the sign and strength of the magnetic coupling of subtle structural factors, such as the trigonal distortion of the metal geometry and the lengthening or the asymmetry of the metal-oxalato bond distances