242 research outputs found

    The influence of dietary lipid composition on skeletal muscle mitochondria from mice following eight months of calorie restriction

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    PMCID: PMC4138957.-- et al.Calorie restriction (CR) has been shown to decrease reactive oxygen species (ROS) production and retard aging in a variety of species. It has been proposed that alterations in membrane saturation are central to these actions of CR. As a step towards testing this theory, mice were assigned to 4 dietary groups (control and 3 CR groups) and fed AIN-93G diets at 95 % (control) or 60 % (CR) of ad libitum for 8 months. To manipulate membrane composition, the primary dietary fats for the CR groups were soybean oil (also used in the control diet), fish oil or lard. Skeletal muscle mitochondrial lipid composition, proton leak, and H2O2 production were measured. Phospholipid fatty acid composition in CR mice was altered in a manner that reflected the n-3 and n-6 fatty acid profiles of their respective dietary lipid sources. Dietary lipid composition did not alter proton leak kinetics between the CR groups. However, the capacity of mitochondrial complex III to produce ROS was decreased in the CR lard compared to the other CR groups. The results of this study indicate that dietary lipid composition can influence ROS production in muscle mitochondria of CR mice. It remains to be determined if lard or other dietary oils can maximize the CRinduced decreases in ROS production. © 2014 Institute of Physiology v.v.i.This work was supported by the National Institutes of Health grants R01 AG028125 and P01 AG025532.Peer Reviewe

    Endothelium-dependent relaxation of human saphenous veins in response to vasopressin and desmopressin

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    Purpose:The goal of this study was to determine the effects of vasopressin and the selective V2-receptor agonist desmopressin on human saphenous veins, with special emphasis on endothelium-mediated responses.Methods:Human saphenous vein segments were obtained from 35 patients undergoing coronary bypass surgery. Paired segments, one normal and the other deendothelized by gentle rubbing, were mounted for isometric recording of tension in organ baths. Concentration-response curves to vasopressin and desmopressin were determined in the presence and in the absence of either the V,-receptor antagonist d(CH2)5Tyr(Me)AVP (10−6 mol/L), the V1-V2 receptor antagonist desGly-d(CH2)5D-Tyr(Et)ValAVP (10−6 mol/L), indomethacin (10−6 mol/L), or NG-nitro-L-arginine methyl ester hydrochloride (L-NAME, 10−4 mol/L).Results:In vein rings under resting tension, vasopressin produced concentration-dependent, endothelium-independent contractions with a concentration of vasopressin producing-half-maximal contractions (EC50) of 3.44 × 10−8 mol/L. The vasopressin V1-receptor antagonist (10−6 mol/L) displaced the control curve to vasopressin 9.86-fold to the right in a parallel manner. In precontracted vein rings previously treated with the V1-antagonist (10−6 mol/L), vasopressin caused endothelium-dependent relaxations. This relaxation was reduced significantly by indomethacin (10−6 mol/L) and unaffected by the V1-V2-receptor antagonist (10−6 mol/L) or by L-NAME (10−4 mol/L). Desmopressin caused endothelium-dependent relaxations in precontracted vein rings that were inhibited by the mixed V1-V2-receptor antagonist and by indomethacin, but not by the V1-antagonist or by pretreatment with L-NAME.Conclusions:These observations indicate that vasopressin exerts contractile effects on human saphenous vein by V1-receptor stimulation. Vasopressin causes dilatation of human saphenous vein only if V1-receptor blockade is present. This relaxation appears to be mediated by the release of relaxant Prostaglandins, probably derived from endothelial cells, and is independent of V2-receptor stimulation or release of nitric oxide. Desmopressin elicits relaxation that is largely dependent on V2-receptor stimulation, which may bring about the release of dilating Prostaglandins from the endothelial cells

    E-learning in “innovation, creativity and entrepreneurship”: Exploring the new opportunities and challenges of technologies

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    Companies and society demand professionals be able to provide creative solutions with added value as well as to implement them in order to face the arising challenges in the increasingly dynamic environment. Although the transversal competence “Innovation, Creativity and Entrepreneurship” is essential for engineers that should find innovative solutions to problems, teachers find many difficulties when training and evaluating their students in the scope of the regular courses: large groups, very adjusted time to technical contents. In this context, the School of Industrial Engineering (ETSII) at Polytechnic University of Valencia (UPV) is aware of the opportunities offered by new information and communication technologies to support teachers in this task while enhancing students’ generic outcomes. For this reason, an e-learning platform has been created on this competence, that offers valuable resources to students to implement this competence throughout the assigned course tasks, and supports teachers prompted to train and evaluate this transversal competence. With this platform, the authors aim to contribute to the still neglected educational aspect of entrepreneurship and address for the first time in an e-learning system its relationship with innovation and creativity

    Shear-induced microstructural transitions in aqueous systems containing an esterquat cationic surfactant

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    Se presenta un estudio basado en técnicas reológicas y de microscopía electrónica de barrido de bajas temperaturas (cryo-SEM) sobre los cambios de microestructura provocados por el flujo en cizalla de dispersiones acuosas de un tensioactivo catiónico tipo esterquat. Se comparan micrografías de cryo-SEM y las respuestas bajo cizalla oscilatoria de dispersiones sin y con cloruro de calcio. Esta última no presenta zona de comportamiento viscoelástico lineal, apuntando su respuesta no lineal a un fenómeno de estructuración inducida por cizalla. Ensayos transitorios de inicio al flujo, entre 0,1s-1 y 2000s-1, confirman que se producen aumentos de viscosidad más acusados con el tiempo de flujo a medida que aumenta la velocidad de cizalla. La técnica de cryo-SEM apoya que los resultados transitorios se deben a que un exceso de energía mecánica provoca transiciones de bicapas de tensioactivo a vesículas. Diferentes ensayos reológicos realizados en serie avalan la naturaleza irreversible, en la escala de tiempo de esta investigación, de las transiciones microestructurales inducidas por cizalla. Se demuestra que a pesar de la presencia de cloruro de calcio (0,1%), la aplicación de una velocidad de cizalla excesiva puede dar lugar a la aparición de respuestas viscoelásticas lineales significativas.This paper deals with a rheological and microstructural (cryo- SEM) characterization of shear-induced microstructure transitions in aqueous dispersions of an esterquat cationic surfactant. Cryo-SEM micrographs and oscillatory shear results of systems containing or not calcium chloride are compared. The addition of calcium chloride precluded the occurrence of significant viscoelastic properties and the estimation of the linear viscoelastic range. The non-linear oscillatory response pointed to the occurrence of incipient shear-induced build-up phenomena. Start-up flow tests between 0.1s-1 and 2000s-1 showed that the increase of viscosity with shear time was more marked as shear rate was increased. Cryo-SEM observations supported that build-up results in transient flow were due to an excess of mechanical energy, which resulted in transitions from surfactant bilayers to vesicles. Several series of rheological tests were carried out to demonstrate that shear-induced microstructure transitions were irreversible in the time scale of this investigation. Despite the addition of calcium chloride (0.1% wt), the shear-induced dispersion of vesicles may provoke the onset of significant linear viscoelasticity.Es presenta un estudi basat en tècniques reològiques i de microscòpia electrònica d’escombratge de baixes temperaturas (cryo-SEM) sobre els canvis de microestructura provocats pel flux en cisalla de dispersions aquoses d’un tensioactiu catiònic tipus esterquat. Es comparen micrografies de cryo-SEM i les respostes sota cisallament oscil•latòri de dispersions sense i amb clorur de calci. Aquesta darrera no presenta zona de comportament viscoelàstic lineal, apuntant la seva resposta no lineal a un fenomen d’estructuració induïda per cisallament. Assaigs transitoris d’inici al flux, entre 0,1s-1 y 2000s-1, confirmen que es produeixen augments de viscositat més acusats amb el temps de flux a mesura que augmenta la velocitat de cisallament. La técnica de cryo-SEM recolza que els resultats transitoris es deuen a que un excés d’energia mecànica provoca transicions de bicapes de tensioactiu a vesícules. Diferents assaigs reològics realitzats en sèrie avalen la naturalesa irreversible, a la escala de temps d’aquesta investigació, de les transicions microestructurals induïdes per cisallament. Es demostra que, tot i la presència de clorur de calci (0,1%), l’aplicació de una velocitat de cisallament excessiva pot donar lloc a l’aparició de respostes viscoelàstiques lineals significatives

    Comparing Hydrolysis and Transglycosylation Reactions Catalyzed by Thermus thermophilus β-Glycosidase. A Combined MD and QM/MM Study

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    The synthesis of oligosaccharides and other carbohydrate derivatives is of relevance for the advancement of glycosciences both at the fundamental and applied level. For many years, glycosyl hydrolases (GHs) have been explored to catalyze the synthesis of glycosidic bonds. In particular, retaining GHs can catalyze a transglycosylation (T) reaction that competes with hydrolysis (H). This has been done either employing controlled conditions in wild type GHs or by engineering new mutants. The goal, which is to increase the T/H ratio, has been achieved with moderate success in several cases despite the fact that the molecular basis for T/H modulation are unclear. Here we have used QM(DFT)/MM calculations to compare the glycosylation, hydrolysis and transglycosylation steps catalyzed by wild type Thermus thermophilus β-glycosidase (family GH1), a retaining glycosyl hydrolase for which a transglycosylation yield of 36% has been determined experimentally. The three transition states have a strong oxocarbenium character and ring conformations between 4H3 and 4E. The atomic charges at the transition states for hydrolysis and transglycosylation are very similar, except for the more negative charge of the oxygen atom of water when compared to that of the acceptor Glc. The glycosylation transition state has a stronger SN2 character than the deglycosylation ones and the proton transfer is less advanced. At the QM(PBE0/TZVP)/MM level, the TS for transglycosylation has shorter O4GLC-C1FUC (forming bond) distance and longer OE2GLU338-C1FUC (breaking) distance than the hydrolysis one, although the HACC proton is closer to the Glu164 base in the hydrolysis TS. The QM(SCC-DFTB)/MM free energy maxima show the inverted situation, although the hydrolysis TS presents significant structural fluctuations. The 3-OHGLC group of the acceptor Glc (transglycosylation) and WAT432 (neighbor water in hydrolysis) are identified to stabilize the oxocarbenium transition states through interaction with O5FUC and O4FUC. The analysis of interaction suggests that perturbing the Glu392-Fuc interaction could increase the T/H ratio, either by direct mutation of this residue or indirectly as reported experimentally in the Asn390I and Phe401S cases. The molecular understanding of similarities and differences between hydrolysis and transglycosylation steps may be of help in the design of new biocatalysts for glycan synthesis

    Life Cycle Thinking for the environmental and financial assessment of rice management systems in the Senegal River Valley

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    [EN] Rice is a staple food in Senegal, which however imports more than 70% of the rice consumed annually to meet its domestic demand. Despite governmental efforts to increase rice self-sufficiency, both rice supply and yields remain low. Senegalese farmers face challenges related to irrigation infrastructure and fertiliser access, besides those derived from climate change. This study applies Life Cycle Assessment (LCA) combined with financial Life Cycle Costing (LCC) to evaluate alternative scenarios for rice management in the Senegal River Valley and identify sustainability hotspots and potential improvements. Specifically, rice cultivation in Ross Be & PRIME;thio (Saint Louis, Senegal) is assessed based on the observed agricultural practices during the dry seasons of 2016 and 2017. Two scenarios capturing conventional (CONV) and intensive (INT) practices are compared to two reference scenarios (SAED scenarios) according to the recommendations of the official agricultural advisory service. The INT scenario generates the lowest impacts per kg of paddy rice in seven out of thirteen impact categories, including climate change, freshwater and marine eutrophication, ozone depletion and water scarcity. This is due to the higher yields (7.4 t ha(-1)) relative to CONV (4.8 t ha(-1)) and the two reference SAED scenarios (6.0 t ha(-1)). The two latter scenarios show the lowest values in the remaining categories, although they also generate slightly lower profits than INT (138 euro t(-1) vs. 149 euro t(-1)) due to increased labour costs for additional fertilisation treatments. The results from both LCA and LCC underline the importance of increasing yields to decrease environ -mental impacts and production costs of rice when estimated per kg of product. Well-designed fertiliser application doses and timing and increased mechanisation can deliver further environmental benefits. Additional improvements (e.g. in irrigation, crop rotations, straw management) could be considered to promote the long -term sustainability and profitability of rice production in Senegal. LCA in combination with financial LCC is identified as a decision-support tool for evaluating the sustainability of alternative crop management practices. Life Cycle Thinking can still benefit from experiential learning based on information exchange between farmers, researchers and extension agents to contribute to a sustainable agriculture and ultimately to food security in Africa.Authors acknowledge the Office of Development Cooperation of the Universitat Politecnica de Valencia (CCD-UPV) for providing funds as part of the project AD1511-UPV. Authors also thank the support of Caritas Spain (especially Vittoria Garoffalo, Soledad Gutierrez, and Pablo Reyero) and Caritas Senegal (especially Alex Tendeng, Andre Diarigne Sene and Michael Diedhiou) for facilitating its implementation.Escobar, N.; Bautista, I.; Peña, N.; Fenollosa Ribera, ML.; Osca Lluch, JM.; Sanjuán Pellicer, MN. (2022). Life Cycle Thinking for the environmental and financial assessment of rice management systems in the Senegal River Valley. Journal of Environmental Management. 310:1-15. https://doi.org/10.1016/j.jenvman.2022.11472211531

    Production of sausages in Turkana, Kenia

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    PòsterTo develop and to determine the feasibility of a project of food nature by means of: -Study of: cultural bases, food habits, climatic conditions. -To elaborate food product covering some of the food needs. Studying all the aspects of the region it will be possible to propose a process of production. The final product will be capable of satisfying one of the most important needs of supply

    Mitochondrial ultrastructure and markers of dynamics in hepatocytes from aged, calorie restricted mice fed with different dietary fats

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    PMCID: PMC4104696In this paper we analyzed changes in hepatocyte mitochondrial mass and ultrastructure as well as in mitochondrial markers of fission/fusion and biogenesis in mice subjected to 40% calorie restriction (CR) for 18. months versus ad libitum-fed controls. Animals subjected to CR were separated into three groups with different dietary fats: soybean oil (also in controls), fish oil and lard. Therefore, the effect of the dietary fat under CR was studied as well. Our results show that CR induced changes in hepatocyte and mitochondrial size, in the volume fraction occupied by mitochondria, and in the number of mitochondria per hepatocyte. Also, mean number of mitochondrial cristae and lengths were significantly higher in all CR groups compared with controls. Finally, CR had no remarkable effects on the expression levels of fission and fusion protein markers. However, considerable differences in many of these parameters were found when comparing the CR groups, supporting the idea that dietary fat plays a relevant role in the modulation of CR effects in aged mice.Supported by NIH grant 1R01AG028125-01A1 (to JJR, PN and JMV), Ministerio de Economía y Competitividad and European FEDERBFU2011-23578 (to JMV), Junta de Andalucía Proyectos de Excelencia grant P09-CVI-4887 (to JMV), Junta de Andalucía Proyectos Internacionales (to JMV), and BIO-276 (Junta de Andalucía and the University of Córdoba, to JMV and EGC). JALD and LFdR were funded by predoctoral fellowships of the Spanish Ministerio de Educación and by BIO-276. HK was funded by a predoctoral fellowship of the Agencia Española de Cooperación Internacional al Desarrollo and by BIO-276.Peer Reviewe

    The influence of dietary fat source on liver and skeletal muscle mitochondrial modifications and lifespan changes in calorie-restricted mice

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    The Membrane Theory of Aging proposes that lifespan is inversely related to the level of unsaturation in membrane phospholipids. Calorie restriction (CR) without malnutrition extends lifespan in many model organisms, which may be related to alterations in membrane phospholipids fatty acids. During the last few years our research focused on studying how altering the predominant fat source affects the outcome of CR in mice. We have established four dietary groups: one control group fed 95 % of a pre-determined ad libitum intake (in order to prevent obesity), and three CR groups fed 40 % less than ad libitum intake. Lipid source for the control and one of the CR groups was soybean oil (high in n-6 PUFA) whereas the two remaining CR groups were fed diets containing fish oil (high in n-3 PUFA), or lard (high in saturated and monounsaturated fatty acids). Dietary intervention periods ranged from 1 to 18 months. We performed a longitudinal lifespan study and a cross-sectional study set up to evaluate several mitochondrial parameters which included fatty acid composition, H+ leak, activities of electron transport chain enzymes, ROS generation, lipid peroxidation, mitochondrial ultrastructure, and mitochondrial apoptotic signaling in liver and skeletal muscle. These approaches applied to different cohorts of mice have independently indicated that lard as a fat source often maximizes the effects of 40 % CR on mice. These effects could be due to significant increases of monounsaturated fatty acids levels, in accordance with the Membrane Theory of Aging.Supported by NIH grant 1R01AG028125 (to JJR, PN and JMV), Ministerio de Economía y Competitividad BFU2011-23578 (to JMV), Junta de Andalucía Proyectos de Excelencia grant P09-CVI-4887 (to JMV), Junta de Andalucía Proyectos Internacionales grant (to JMV), and BIO-276 (Junta de Andalucía and the University of Córdoba, to JMV). RdC is funded by the Intramural Research program of the NIA/NIH. JALD, JA, LFdR and EGC were funded by a predoctoral fellowship of the Spanish Ministerio de Educación and BIO-276. HK was funded by a predoctoral fellowship of the Agencia Española de Cooperación Internacional al Desarrollo and BIO-276. MCR and MdR were supported by BIO-276.Peer Reviewe

    Mitochondrial dynamics in hepatocytes from mice fed caloric restriction diets with different fat sources

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    Resumen del trabajo presentado al XIV Congresos de la Sociedad Española de Biología Celular, celebrado en Málaga del 12 al 15 de diciembre de 2011.Peer reviewe
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