511 research outputs found

    MARKET SEGMENTATION AND WILLINGNESS TO PAY FOR ORGANIC PRODUCTS IN SPAIN

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    In recent years, consumer concerns on environmental and health issues related to food products have increased and, as a result, the demand for organically grown production has grown. Higher costs of production and retailer margins generate a gap between real prices and those that consumers are willing to pay for organic food. In this article, consumer willingness to pay for organic food in two Spanish regions is analyzed. Markets in both regions are segmented considering consumers lifestyles. Results indicate that consumers concerned about healthy diet and environmental degradation are the most likely to buy organic food, and are willing to pay a high premium. Organic attributes are easily identified in perishable products as the premium consumers would pay for organic meat, fruits, and vegetables is higher.Demand and Price Analysis,

    Confidence in the Beef Production System as a Key Factor to Mitigate the Impact of BSE on Beef Consumption

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    Recent food scares in the food market has caused a reduction in consumer's confidence in the food system that it has induced a significant reduction in consumption in a sector, the beef sector that was already characterized by a saturated trend in quantity terms. In this context, all participants in the beef production system are facing to a great challenge, to retrieve consumer's confidence in the food chain and to mitigate the reduction in beef consumption. The aim of the paper is to analyse the impact of consumer's confidence in the food system as well as other factors on the explanation of food consumption reduction. A structural modelling approach has been used to analyse factors affecting the reduction in beef consumption in two different regions characterised by different production systems and different marketing strategies (PGI beef label). Results indicate that main factor explaining the reduction in beef consumption is the confidence in the beef and a positive relation has been found. Moreover, confidence in a product is directly related to the perceived quality offered by farmers and other decision makers on the beef chain, and to the consumer involvement with the product. Therefore, the main implication is that participants in the food chain has to develop adequate communication strategies such as quality labelling in order to increase consumers perceive quality because, higher quality perception will recover consumers' confidence in beef, and therefore, it will mitigate beef consumption reduction.food confidence, consumer behaviour, structural equation modelling, beef sector, quality label, Food Consumption/Nutrition/Food Safety,

    The inside story of adenosine

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    Several physiological functions of adenosine (Ado) appear to be mediated by four G protein-coupled Ado receptors. Ado is produced extracellularly from the catabolism of the excreted ATP, or intracellularly from AMP, and then released through its transporter. High level of intracellular Ado occurs only at low energy charge, as an intermediate of ATP breakdown, leading to hypoxanthine production. AMP, the direct precursor of Ado, is now considered as an important stress signal inside cell triggering metabolic regulation through activation of a specific AMP-dependent protein kinase. Intracellular Ado produced from AMP by allosterically regulated nucleotidases can be regarded as a stress signal as well. To study the receptor-independent effects of Ado, several experimental approaches have been proposed, such as inhibition or silencing of key enzymes of Ado metabolism, knockdown of Ado receptors in animals, the use of antagonists, or cell treatment with deoxyadenosine, which is substrate of the enzymes acting on Ado, but is unable to interact with Ado receptors. In this way, it was demonstrated that, among other functions, intracellular Ado modulates angiogenesis by regulating promoter methylation, induces hypothermia, promotes apoptosis in sympathetic neurons, and, in the case of oxygen and glucose deprivation, exerts a cytoprotective effect by replenishing the ATP pool

    Nuclear Lipids in the Nervous System: What they do in Health and Disease

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    In the last 20 years it has been widely demonstrated that cell nucleus contains neutral and polar lipids localized in nuclear membranes, nucleoli, nuclear matrix and chromatin. Nuclear lipids may show specific organization forming nuclear lipid microdomains and have both structural and functional roles. Depending on their localization, nuclear lipids play different roles such as the regulation of nuclear membrane and nuclear matrix fluidity but they also can act as platforms for vitamin and hormone function, for active chromatin anchoring, and for the regulation of gene expression, DNA duplication and transcription. Crosstalk among different kinds of lipid signalling pathways influence the physiopathology of numerous cell types. In neural cells the nuclear lipids are involved in cell proliferation, differentiation, inflammation, migration and apoptosis. Abnormal metabolism of nuclear lipids might be closely associated with tumorigenesis and neurodegenerative diseases such as Alzheimer disease and Parkinson disease among others

    Vitamin D and Sphingolipids: Role in Bone and Neural System

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    1-Alpha,25-dihydroxyvitamin D3 (1,25(OH)2D3) is known to play an important physiological role on growth and differentiation in a variety of nonmalignant and malignant cell types through classical actions, mediated by its specific receptor (VDR), and nongenomic actions resulting in the activation of specific signalling pathways. Due to the broad distribution of Vitamin D Receptor (VDR) in many tissues and the ability of 1,25(OH)2D3 to regulate fundamental processes, such as cell proliferation and differentiation, this steroid hormone has been suggested in the treatment of different diseases, from cancer to neurodegenerative diseases. In fact, structural 1,25(OH)2D3 analogues, with weaker collateral effects, have recently entered in clinical trials. Other interesting molecules due to their pleiotropic actions are the bioactive sphingolipids (SLs), in particular ceramide (Cer) and sphingosine 1-phosphate (S1P). Cells maintain a dynamic balance of these metabolites since Cer and sphingoid bases mediate cell death, while S1P exerts mitogenic effects and promotes differentiation of several cell types including osteogenic and neural cells. The biological actions of 1,25(OH)2D3 and SLs, in particular S1P, share many common effectors, including calcium regulation, growth factor expression, inflammatory cytokines, etc., but whether they could act synergistically is still unknown and deserves further investigation

    Crosstalk between sphingolipids and vitamin D3: potential role in the nervous system

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    Sphingolipids are both structural and bioactive compounds. In particular, ceramide and sphingosine 1-phosphate regulate cell fate, inflammation and excitability. 1-α,25-dihydroxyvitamin D3 (1,25(OH)2D3) is known to play an important physiological role in growth and differentiation in a variety of cell types, including neural cells, through genomic actions mediated by its specific receptor, and non-genomic effects that result in the activation of specific signalling pathways. 1,25(OH)2D3 and sphingolipids, in particular sphingosine 1-phosphate, share many common effectors, including calcium regulation, growth factors and inflammatory cytokines, but it is still not known whether they can act synergistically. Alterations in the signalling and concentrations of sphingolipids and 1,25(OH)2D3 have been found in neurodegenerative diseases and fingolimod, a structural analogue of sphingosine, has been approved for the treatment of multiple sclerosis. This review, after a brief description of the role of sphingolipids and 1,25(OH)2D3, will focus on the potential crosstalk between sphingolipids and 1,25(OH)2D3 in neural cell

    Propuesta de mejora en las áreas de producción y logística para incrementar la rentabilidad de la empresa Fabricación y Servicio Técnico S.R.L

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    RESUMEN El presente trabajo de investigación tiene como objetivo analizar las Áreas de Producción y Logística de la línea de producción de granallado y pintado de balones de GLP de 10 Kg con el fin de incrementar la rentabilidad de la empresa Fabricación y Servicio Técnico S.R.L. (en adelante FASERTEC). La empresa por estudiar se dedica a fabricar y brindar servicios técnicos a empresas del sector industrial. La investigación se inició con el diagnóstico de la situación actual de la empresa, en el cual muestra que existe el uso ineficiente de recursos de las áreas de producción y logística, lo que provoca que afecte directamente a la rentabilidad de la empresa. Por ello, se propone planes de mejora a través de herramientas, técnicas y metodologías de Ingeniería Industrial, tales como: Planificación de Requerimiento de Materiales (MRP), gestión del talento humano, gestión de inventarios, plan de capacitación, lean manufacturing - 5S y distribución de planta (layout). Luego se evaluó la propuesta, recalculando los indicadores diseñados inicialmente para obtener una medición objetiva sobre el beneficio percibido. Se demuestra que gracias a las metodologías aplicadas se pudo mejorar los indicadores, obteniendo un beneficio total de S/16,609.57 soles. Teniendo como resultado un VAN de S/. 28,980.83, un TIR de 61.00% de y un B/C de 2.66; con lo que se concluye que la propuesta es rentable para desarrollarse en la empresa FASERTEC. PALABRAS CLAVE: Rentabilidad, Planificación de Requerimiento de Materiales; gestión del talento humano, gestión de inventarios, plan de capacitación, lean manufacturing y distribución de planta

    Emerging Role of Purine Metabolizing Enzymes in Brain Function and Tumors

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    The growing evidence of the involvement of purine compounds in signaling, of nucleotide imbalance in tumorigenesis, the discovery of purinosome and its regulation, cast new light on purine metabolism, indicating that well known biochemical pathways may still surprise. Adenosine deaminase is important not only to preserve functionality of immune system but also to ensure a correct development and function of central nervous system, probably because its activity regulates the extracellular concentration of adenosine and therefore its function in brain. A lot of work has been done on extracellular 5'-nucleotidase and its involvement in the purinergic signaling, but also intracellular nucleotidases, which regulate the purine nucleotide homeostasis, play unexpected roles, not only in tumorigenesis but also in brain function. Hypoxanthine guanine phosphoribosyl transferase (HPRT) appears to have a role in the purinosome formation and, therefore, in the regulation of purine synthesis rate during cell cycle with implications in brain development and tumors. The final product of purine catabolism, uric acid, also plays a recently highlighted novel role. In this review, we discuss the molecular mechanisms underlying the pathological manifestations of purine dysmetabolisms, focusing on the newly described/hypothesized roles of cytosolic 5'-nucleotidase II, adenosine kinase, adenosine deaminase, HPRT, and xanthine oxidase

    Cytotoxic effects and apoptotic signalling mechanisms of the sesquiterpenoid euplotin C, a secondary metabolite of the marine ciliate Euplotes crassus, in tumour cells

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    Most antitumour agents with cytotoxic properties induce apoptosis. The lipophilic compound euplotin C, isolated from the ciliate Euplotes crassus, is toxic to a number of different opportunistic or pathogenic microorganisms, although its mechanism of action is currently unknown. We report here that euplotin C is a powerful cytotoxic and pro-apoptotic agent in mouse AtT-20 and rat PC12 tumour-derived cell lines. In addition, we provide evidence that euplotin C treatment results in rapid activation of ryanodine receptors, depletion of Ca2+ stores in the endoplasmic reticulum (ER), the release of cytochrome c from the mitochondria, activation of caspase-12, and activation of caspase-3, leading to apoptosis. Intracellular Ca2+ overload is an early event which induces apoptosis and is parallelled by ER stress and the release of cytochrome c, whereas caspase-12 may be activated by euplotin C at a later stage in the apoptosis pathway. These events, either independently or concomitantly, lead to the activation of the caspase-3 and its downstream effectors, triggering the cell to undergo apoptosis. These results demonstrate that euplotin C may be considered for the design of cytotoxic and pro-apoptotic new drugs.L'articolo è disponibile sul sito dell'editore http://www.springerlink.com

    Molecular mechanisms of euplotin C-induced apoptosis: involvement of mitochondrial dysfunction, oxidative stress and proteases

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    The metabolite euplotin C (EC), isolated from the marine ciliate Euplotes crassus, is a powerful cytotoxic and pro-apoptotic agent in tumour cell lines. For instance, EC induces the rapid depletion of ryanodine Ca2+ stores, the release of cytochrome c from the mitochondria, and the activation of caspase-3, leading to apoptosis. The purpose of this study was to gain further insight into the mechanisms of EC-induced apoptosis in rat pheochromocytoma PC12 cells. We found that EC increases Bax/Bcl-2 ratio and that Bax is responsible of the EC-induced dissipation of the mitochondrial membrane potential (Δψm). In addition, EC induces the generation of reactive oxygene species (ROS) without involvement of p53. The inhibition of ROS generation prevents, at least in part, the pro-apoptotic effects of EC as well as the effects of EC on Bax, Δψm and intracellular free Ca2+, indicating a cross-talk between different pathways. However, definition of the effector cascade turns out to be more complex than expected and caspase-independent mechanisms, acting in parallel with caspases, should also be considered. Among them, EC increases the expression/activity of calpains downstream of ROS generation, although calpains seem to exert protective effects.L'articolo è disponibile sul sito dell'editore http://www.springerlink.co
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