227 research outputs found
Growth-promoting effects of sustained swimming in fingerlings of gilthead sea bream (Sparus aurata L.)
Fish growth is strongly influenced by environmental and nutritional factors and changing culture conditions can help optimize it. The importance of early-life experience on the muscle phenotype later in life is well known. Here, we study the effects of 5 weeks of moderate and sustained swimming activity (5 BL s) in gilthead sea bream during early development. We analysed growth and body indexes, plasma IGF-I and GH levels, feed conversion, composition [proximate and isotopic (N/C)] and metabolic key enzymes (COX, CS, LDH, HOAD, HK, ALAT, ASAT) of white muscle. Moderate and continuous exercise in fingerlings of gilthead sea bream increased plasma IGF-I, whereas it reduced plasma GH. Under these conditions, growth rate improved without any modification to feed intake through an increase in muscle mass and a reduction in mesenteric fat deposits. There were no changes in the content and turnover of muscle proteins and lipid reserves. Glycogen stores were maintained, but glycogen turnover was higher in white muscle of exercised fish. A lower LDH/CS ratio demonstrated an improvement in the aerobic capacity of white muscle, while a reduction in the COX/CS ratio possibly indicated a functional adaptation of mitochondria to adjust to the tissue-specific energy demand and metabolic fuel availability in exercised fish. We discuss the synergistic effects of dietary nutrients and sustained exercise on the different mitochondrial responses.A.M.C and E.J.V. are supported by a predoctoral fellowship from the “Ministerio de Ciencia e Innovación” (MICINN) and A.M.P. by a fellowship from the University of Barcelona (APIF-2012). This study was supported by the projects from the MICINN AGL2012-39768, and the “Xarxa de Refèrencia d’R+D+I en Aqüicultura” and the SGR2009-00402 from the “Generalitat de Catalunya”.Peer Reviewe
Responsabilidad Social Corporativa Interna como creación de valor: hipocresía y realidad
Este trabajo trata sobre la responsabilidad aplicada al mundo de las empresas. Más concretamente, acerca de una parte de la misma, la vertiente interna de la denominada Responsabilidad Social Corporativa. En el contexto actual de crisis económica en el que nos encontramos, la mayoría de las empresas se plantean continuamente la reducción de sus plantillas como único paliativo para combatirla. Esto ha llevado a la sociedad a reclamar un mayor interés de las empresas por las cuestiones vinculadas con la RSC. Todo ello, partiendo de la base de una relación de compromiso entre la empresa y los trabajadores, unidos por un interés común y una relación de respeto, solidaridad, confianza y compromiso entre la empresa y este grupo de interés tan importante, como son los propios trabajadores. Respecto a la parte práctica hemos querido abordar, a modo de denuncia, el problema que se plantea en la sociedad con empresas que afirman ser socialmente responsables y, en cambio, realizan prácticas no éticas con sus trabajadores
Relationship of oxidized low density lipoprotein with lipid profile and oxidative stress markers in healthy young adults: a translational study
<p>Abstract</p> <p>Background</p> <p>Despite oxidized low density lipoprotein (ox-LDL) plays important roles in the pro-inflammatory and atherosclerotic processes, the relationships with metabolic and oxidative stress biomarkers have been only scarcely investigated in young adult people. Thus, the aim of this study was to assess plasma ox-LDL concentrations and the potential association with oxidative stress markers as well as with anthropometric and metabolic features in healthy young adults.</p> <p>Methods</p> <p>This study enrolled 160 healthy subjects (92 women/68 men; 23 ± 4 y; 22.0 ± 2.9 kg/m<sup>2</sup>). Anthropometry, body composition, blood pressure, lifestyle features, biochemical data, and oxidative stress markers were assessed with validated tools. Selenium, copper, and zinc nail concentrations were measured by atomic absorption spectrophotometry.</p> <p>Results</p> <p>Total cholesterol (TC), LDL-c and uric acid concentrations, TC-to-HDL-c ratio, and glutathione peroxidase (GPx) activity were positive predictors of ox-LDL concentrations, while nail selenium level (NSL) was a negative predictor, independently of gender, age, smoking status, physical activity. Those individuals included in the highest tertile of GPx activity (≥611 nmol/[mL/min]) and of NSL (≥430 ng/g of nail) had higher and lower ox-LDL concentrations, respectively, independently of the same covariates plus truncal fat or body mass index, and total cholesterol or LDL-c concentrations.</p> <p>Conclusions</p> <p>Ox-LDL concentrations were significantly associated with lipid biomarkers, GPx activity, uric acid concentration, and NSL, independently of different assayed covariates, in young healthy adults. These findings jointly suggest the early and complex relationship between lipid profile and redox status balance.</p
Microbial cellulose from a komagataeibacter intermedius strain isolated from commercial wine vinegar
In this study a new bacterial cellulose (BC) producer isolated from commercial vinegar is identified as Komagataeibacter intermedius JF2 based on the examination of general taxonomical characteristics, 16S rDNA sequence analysis, and MALDI-TOF mass spectrometry. The cellulose produced is studied in terms of morphology by scanning electron microscopy, crystallinity by X-Ray diffraction, structure by Fourier transform infrared spectroscopy, and water absorption capacity. BC yield and characteristics of the cellulose produced by the new isolated JF2 are compared with those of the well-known and commonly-used BC producer Komagataeibacter xylinus. Yield of cellulose production was higher for JF2 than for K. xylinus grown on several culture media. JF2 exhibited maximum BC production (1.6 g/L) growing on HS medium supplemented with mannitol. The molecular structure of the produced cellulose was the same for both strains and it was in concordance with that of BC. The nanocellulose fibers produced by JF2 showed a higher degree of crystallinity and a more homogeneous size distribution than those produced by K. xylinus. The results suggested that Komagataeibacter intermedius JF2 could be a suitable candidate as a BC producer for biotechnological applications.Peer ReviewedPostprint (author's final draft
Using stable isotope analysis to study skin mucus exudation and renewal in fish
Fish skin mucus is proposed as a novel target for the study of physiological condition and to conduct minimally invasive monitoring of fish. Whereas mucus composition has been a major interest of recent studies, no practical techniques have been proposed to gain understanding of the capacity and rhythm of production and exudation. Here, we used stable isotope analysis (SIA) with a labelled meal, packaged in gelatine capsules, to evaluate mucus production and renewal in a fish model, the gilthead sea bream (Sparus aurata). Mucus 13C- and 15N-enrichment reached higher levels at 12 h post-ingestion without significant differences at 24 h. When the formation of new mucus was induced, 13C-enrichment in the new mucus doubled whereas 15N-enrichment only increased by 10%. These results indicate the feasibility of adopting SIA in mucus studies and allow us to propose this methodology as a means to improve knowledge of mucus turnover in fish and other animals
Análisis comparativo de la pobreza en Aragón y España
Análisis de la evolución de la pobreza en España durante un periodo de tiempo poniendo el énfasis en la diferencia entre hombres y mujeres. Y en comparativa de los datos de Aragón con los del resto de España para visualizar cual es la coyuntura a nivel autonómico.Por ultimo expresar ideas para dar posibles soluciones a los resultados obtenidos del estudio.<br /
Bacterial cellulose matrices to develop enzymatically active paper
This work studies the suitability of bacterial cellulose (BC) matrices to prepare enzymatically active nanocomposites, in a framework of more environmentally friendly methodologies. After BC production and purification, two kind of matrices were obtained: BC in aqueous suspension and BC paper. A lipase was immobilised onto the BC matrices by physical adsorption, obtaining Lipase/BC nanocomposites. Neither morphology nor crystallinity, measured by scanning electron microscopy (SEM) and X-Ray diffractometry (XRD) respectively, of the BC were affected by the binding of the protein. The activity of Lipase/BC suspension and Lipase/BC paper was tested under different conditions, and the operational properties of the enzyme were evaluated. A shift towards higher temperatures, a broader pH activity range, and slight differences in the substrate preference were observed in the immobilised lipase, compared with the free enzyme. Specific activity was higher for Lipase/BC suspension (4.2 U/mg) than for Lipase/BC paper (1.7 U/mg) nanocomposites. However, Lipase/BC paper nanocomposites showed improved thermal stability, reusability, and durability. Enzyme immobilised onto BC paper retained 60% of its activity after 48 h at 60 ºC. It maintained 100% of the original activity after being recycled 10 times at pH 7 at 60 ºC and it remained active after being stored for more than a month at room temperature. The results suggested that lipase/BC nanocomposites are promising biomaterials for the development of green biotechnological devices with potential application in industrials bioprocesses of detergents and food industry and biomedicine. Lipase/BC paper nanocomposite might be a key component of bioactive paper for developing simple, handheld, and disposable devices
Development of an antimicrobial bioactive paper made from bacterial cellulose
Bacterial cellulose (BC) has emerged as an attractive adsorptive material for antimicrobial agents due to its fine network structure, its large surface area, and its high porosity. In the present study, BC paper was first produced and then lysozymewas immobilized onto it by physical adsorption, obtaining a composite of lysozyme-BC paper. The morphology and the crystalline structure of the composite were similar to that of BC paper as examined by scanning electron microscopy and X-ray diffraction, respectively. Regarding operational properties, specific activities of immobilized and free lysozymewere similar. Moreover, immobilized enzyme showed a broaderworking temperature and higher thermal stability. The composites maintained its activity for at least 80 dayswithout any special storage. Lysozyme-BC paper displayed antimicrobial activity against Gram-positive and Gram-negative bacteria, inhibiting their growth by 82% and 68%, respectively. Additionally, the presence of lysozyme increased the antioxidant activity of BC paper by 30%. The results indicated that BC is a suitable material to produce bioactive paper as it provides a biocompatible environment without compromising the activity of the immobilized protein. BC paper with antimicrobial and antioxidant properties may have application in the field of active packaging
Growth-promoting effects of sustained swimming in fingerlings of glithead sea bream (Sparus aurata L.)
Fish growth is strongly influenced by environmental and nutritional factors and changing culture conditions can help optimize it. The importance of early-life experience on the muscle phenotype later in life is well known. Here, we study the effects of 5 weeks of moderate and sustained swimming activity (5 BL s−1) in gilthead sea bream during early development. We analysed growth and body indexes, plasma IGF-I and GH levels, feed conversion, composition [proximate and isotopic (15N/13C)] and metabolic key enzymes (COX, CS, LDH, HOAD, HK, ALAT, ASAT) of white muscle. Moderate and continuous exercise in fingerlings of gilthead sea bream increased plasma IGF-I, whereas it reduced plasma GH. Under these conditions, growth rate improved without any modification to feed intake through an increase in muscle mass and a reduction in mesenteric fat deposits. There were no changes in the content and turnover of muscle proteins and lipid reserves. Glycogen stores were maintained, but glycogen turnover was higher in white muscle of exercised fish. A lower LDH/CS ratio demonstrated an improvement in the aerobic capacity of white muscle, while a reduction in the COX/CS ratio possibly indicated a functional adaptation of mitochondria to adjust to the tissue-specific energy demand and metabolic fuel availability in exercised fish. We discuss the synergistic effects of dietary nutrients and sustained exercise on the different mitochondrial responses
Bacterial Cellulose-Chitosan paper with antimicrobial and antioxidant activities
The production of paper-based bacterial cellulose-chitosan (BC-Ch) nanocomposites was accomplished following two different approaches. In the first, BC paper sheets were produced and then immersed in an aqueous solution of chitosan (BC-ChI); in the second, BC pulp was impregnated with chitosan prior to the production of paper sheets (BC-ChM). BC-Ch nanocomposites were investigated in terms of physical characteristics, antimicrobial and antioxidant properties, and the ability to inhibit the formation of biofilms on their surface. The two types of BC-Ch nanocomposites maintained the hydrophobic character, the air barrier properties, and the high crystallinity of the BC paper. However, BC-ChI showed a surface with a denser fiber network and with smaller pores than those of BC-ChM. Only 5% of the chitosan leached from the BC-Ch nanocomposites after 96 h of incubation in an aqueous medium, indicating that it was well retained by the BC paper matrix. BC-Ch nanocomposites displayed antimicrobial activity, inhibiting growth of and having a killing effect against bacteria Staphylococcus aureus and Pseudomonas aeruginosa and yeast Candida albicans. Moreover, BC-Ch papers showed activity against the formation of a biofilm on their surface. The incorporation of chitosan increased the antioxidant activity of the BC paper. Paper-based BC-Ch nanocomposites combined the physical properties of BC paper and the antimicrobial, antibiofilm, and antioxidant activities of chitosan
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