151 research outputs found

    Disposition of a Glucose Load into Hepatic Glycogen by Direct and Indirect Pathways in Juvenile Seabass and Seabream

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    In carnivorous fish, conversion of a glucose load to hepatic glycogen is widely used to assess their metabolic flexibility towards carbohydrate utilization, but the activities of direct and indirect pathways in this setting are unclear. We assessed the conversion of an intraperitoneal glucose load (2 g.kg−1) enriched with [U-13C6]glucose to hepatic glycogen in juvenile seabass and seabream. 13C-NMR analysis of glycogen was used to determine the contribution of the load to glycogen synthesis via direct and indirect pathways at 48-hr post-injection. For seabass, [U-13C6]glucose was accompanied by deuterated water and 2H-NMR analysis of glycogen 2H-enrichment, allowing endogenous substrate contributions to be assessed as well. For fasted seabass and seabream, 47 ± 5% and 64 ± 10% of glycogen was synthesized from the load, respectively. Direct and indirect pathways contributed equally (25 ± 3% direct, 21 ± 1% indirect for seabass; 35 ± 7% direct, 29 ± 4% indirect for seabream). In fasted seabass, integration of 2H- and 13C-NMR analysis indicated that endogenous glycerol and anaplerotic substrates contributed an additional 7 ± 2% and 7 ± 1%, respectively. In fed seabass, glucose load contributions were residual and endogenous contributions were negligible. Concluding, direct and indirect pathways contributed equally and substantially to fasting hepatic glycogen repletion from a glucose load in juvenile seabream and seabass

    Effects of dietary carbohydrate on hepatic de novo lipogenesis in European seabass (Dicentrarchus labrax L.)

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    Farmed seabass have higher adiposity than their wild counterparts and this is often attributed to carbohydrate (CHO) feeding. Whether this reflects a reduction in fat oxidation, increased de novo lipogenesis (DNL), or both, is not known. To study the effects of high CHO diets on hepatic TG biosynthesis, hepatic TG deuterium (2H) enrichment was determined following 6 days in 2H-enriched tank water for fish fed with a no-CHO control diet (CTRL), and diets with digestible starch (DS) and raw starch (RS). Hepatic fractional synthetic rates (FSRs, percent per day-1) were calculated for hepatic TG-glyceryl and FA moieties through 2H NMR analysis. Glyceryl FSRs exceeded FA FSRs in all cases, indicating active cycling. DS fish did not show increased lipogenic potential compared to CTRL. RS fish had lower glyceryl FSRs compared with the other diets and negligible levels of FA FSRs despite similar hepatic TG levels to CTRL. DS-fed fish showed higher activity for enzymes that can provide NADPH for lipogenesis, relative to CTRL in the case of glucose-6-phosphate dehydrogenase (G6PDH) and relative to RS for both G6PDH and 6-phosphogluconate dehydrogenase. This approach indicated that elevated hepatic adiposity from DS feeding was not attributable to increased DNL

    Fine Structure in the β\beta-Delayed Proton Decay of 33^{33}Ar

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    Low energy beta-delayed protons from 33^{33}Ar have been measured for the first time. The data reveal states, which, despite unfavourable barrier penetrability values, strongly decay to the first excited 2+^+ state in 32^{32}S. The observation is discussed in terms of the standard shell model. A natural explanation is provided by the large spectroscopic amplitudes, involving s1/2s_{1/2} and d3/2d_{3/2} orbitals, as well as the ll=0 barrier penetrability, favouring the decay to the 2+^+ state

    Desarrollo de una plataforma de diseño e ingeniería naval

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    Due to the increase of the complexity in the production operations, and to the low times of delivery that demands the present market of the naval sector, it is necessary to use of CAD/CAE programs that acquire the paper of integrators of the phases of design, planning and the processes of manufacture. In a new ship, a high amount of information is handled, and totally managed in two dimensions until the finish stage of the project, previous to the manufacture. Then, begins the development of the steel in three dimensions. Therefore, during the project evolution there is not a complete 3D representation of the ship, which forces in numerous occasions to make modifications when the ship is already constructed. This increases the manufacture’s cost and delays the delivery time. These modifications could be avoided with a 3D model that allows the synchronized visualization of all its components, as happen when they are constructed.MSC: 68Nxx, 68U07Debido al incremento de complejidad en las operaciones de producción, y a los bajos tiempos de entrega que exige el mercado actual del sector naval, es necesario el manejo de aplicaciones CAD/CAE que adquieran el papel de integradoras entre las fases de diseño, la planificación y los procesos de fabricación. En un buque de nueva construcción la cantidad de información que se maneja es muy elevada, gestionándose íntegramente en dos dimensiones hasta alcanzar la última fase de proyecto, previa a la fabricación, donde ya empieza a ser común realizar el desarrollo del acero en tres dimensiones. Por lo tanto, durante la evolución del proyecto no se dispone en ningún momento de una representación 3D del buque completo, lo que obliga en numerosas ocasiones a realizar modificaciones una vez que el buque está ya construido, elevando de esta manera el coste de su fabricación y retrasando los tiempos de entrega. Dichas modificaciones se podrían evitar con un modelo 3D que permita la visualización simultánea de todos sus componentes, tal y como sucede cuando ya está construidoMSC: 68Nxx, 68U0

    Desarrollo de una plataforma de diseño e ingeniería naval

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    Due to the increase in complexity in production operations, and the low delivery times required by the current market in the naval sector, it is necessary to handle CAD / CAE applications that acquire the role of integrators between the design, planning and manufacturing processes In a newly built vessel the amount of information that is handled is very high, being managed entirely in two dimensions until reaching the last phase of the project, prior to manufacturing, where the development of steel in three dimensions is already beginning to be common. Therefore, during the evolution of the project, a 3D representation of the complete ship is not available at any time, forcing numerous modifications to be made once the ship is already built, thus raising the cost of its manufacture and delaying delivery times. Such modifications could be avoided with a 3D model that allows simultaneous visualization of all its components, just as it is when it is already built.Debido al incremento de complejidad en las operaciones de producción, y a los bajos tiempos de entrega que exige el mercado actual del sector naval, es necesario el manejo de aplicaciones CAD/CAE que adquieran el papel de integradoras entre las fases de diseño, la planificación y los procesos de fabricación. En un buque de nueva construcción la cantidad de información que se maneja es muy elevada, gestionándose íntegramente en dos dimensiones hasta alcanzar la última fase de proyecto, previa a la fabricación, donde ya empieza a ser común realizar el desarrollo del acero en tres dimensiones. Por lo tanto, durante la evolución del proyecto no se dispone en ningún momento de una representación 3D del buque completo, lo que obliga en numerosas ocasiones a realizar modificaciones una vez que el buque está ya construido, elevando de esta manera el coste de su fabricación y retrasando los tiempos de entrega. Dichas modificaciones se podrían evitar con un modelo 3D que permita la visualización simultánea de todos sus componentes, tal y como sucede cuando ya está construid

    Low HER2 expression in normal breast epithelium enables dedifferentiation and malignant transformation via chromatin opening.

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    Overexpression of the HER2 protein in breast cancer patients is a predictor of poor prognosis and resistance to therapies. We used an inducible breast cancer transformation system that allows investigation of early molecular changes. HER2 overexpression to similar levels as those observed in a subtype of HER2-positive breast cancer patients induced transformation of MCF10A cells and resulted in gross morphological changes, increased anchorage-independent growth of cells, and altered the transcriptional programme of genes associated with oncogenic transformation. Global phosphoproteomic analysis during HER2 induction predominantly detected an increase in protein phosphorylation. Intriguingly, this correlated with chromatin opening, as measured by ATAC-seq on acini isolated from 3D cell culture. HER2 overexpression resulted in opening of many distal regulatory regions and promoted reprogramming-associated heterogeneity. We found that a subset of cells acquired a dedifferentiated breast stem-like phenotype, making them likely candidates for malignant transformation. Our data show that this population of cells, which counterintuitively enriches for relatively low HER2 protein abundance and increased chromatin accessibility, possesses transformational drive, resulting in increased anchorage-independent growth in vitro compared to cells not displaying a stem-like phenotype

    Chitosan-mediated shRNA knockdown of cytosolic alanine aminotransferase improves hepatic carbohydrate metabolism

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    Alanine aminotransferase (ALT) catalyses a transamination reaction that links carbohydrate and amino acid metabolism. In this study, we examined the effect of silencing cytosolic ALT (cALT) expression on the hepatic metabolism in Sparus aurata. A number of siRNA and shRNA designed to down-regulate cALT expression were validated in HEK-293 cells transfected with plasmids expressing S. aurata cALT or mitochondrial ALT (mALT) isoforms: ALT silencing significantly decreased the expression levels of S. aurata mRNA cALT1 to 62 % (siRNA) and 48 % (shRNA) of the values observed in control cells. The effect of cALT silencing was analysed in the liver of S. aurata 72 h after intraperitoneal injection of chitosan-tripolyphosphate (TPP) nanoparticles complexed with a plasmid encoding a shRNA to down-regulate cALT expression (pCpG-si1sh1). In fish fed diets with different ratio of protein to carbohydrate and treated with chitosan-TPP-pCpG-si1sh1, cALT1 and cALT2 mRNA levels significantly decreased irrespective of the diet. Consistently, ALT activity decreased in liver of treated animals. In the liver of S. aurata treated with chitosan-TPP-pCpG-si1sh1 nanoparticles, down-regulation of cALT expression increased the activity of key enzymes in glycolysis (6-phosphofructo-1-kinase and pyruvate kinase) and protein metabolism (glutamate dehydrogenase). Besides showing for the first time that administration of chitosan-TPP-pCpG-si1sh1 nanoparticles silences hepatic cALT expression in vivo, our data support that down-regulation of cALT could improve the use of dietary carbohydrates to obtain energy and spare protein catabolis

    Exome sequencing of early-onset patients supports genetic heterogeneity in colorectal cancer

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    Colorectal cancer (CRC) is a complex disease that can be caused by a spectrum of genetic variants ranging from low to high penetrance changes, that interact with the environment to determine which individuals will develop the disease. In this study, we sequenced 20 early-onset CRC patients to discover novel genetic variants that could be linked to the prompt disease development. Eight genes, CHAD, CHD1L, ERCC6, IGTB7, PTPN13, SPATA20, TDG and TGS1, were selected and re-sequenced in a further 304 early onset CRC patients to search for rare, high-impact variants. Although we found a recurring truncating variant in the TDG gene shared by two independent patients, the results obtained did not help consolidate any of the candidates as promising CRC predisposing genes. However, we found that potential risk alleles in our extended list of candidate variants have a tendency to appear at higher numbers in younger cases. This supports the idea that CRC onset may be oligogenic in nature and may show molecular heterogeneity. Further, larger and robust studies are thus needed to unravel the genetics behind early-onset CRC development, coupled with novel functional analyses and omic approaches that may offer complementary insight

    ECLIM-SEHOP, a new platform to set up and develop international academic clinical trials for childhood cancer and blood disorders in Spain

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    Introduction: Cancer and blood disorders in children are rare. The progressive improvement in survival over the last decades largely relies on the development of international academic clinical trials that gather the sufcient number of patients globally to elaborate solid conclusions and drive changes in clinical practice. The participation of Spain into large international academic trials has traditionally lagged behind of other European countries, mainly due to the burden of administrative tasks to open new studies, lack of fnancial support and limited research infrastructure in our hospitals. Methods: The objective of ECLIM-SEHOP platform (Ensayos Clínicos Internacionales Multicéntricos-SEHOP) is to overcome these difculties and position Spain among the European countries leading the advances in cancer and blood disorders, facilitate the access of our patients to novel diagnostic and therapeutic approaches and, most importantly, continue to improve survival and reducing long-term sequelae. ECLIM-SEHOP provides to the Spanish clinical investigators with the necessary infrastructural support to open and implement academic clinical trials and registries. Results: In less than 3 years from its inception, the platform has provided support to 20 clinical trials and 8 observational studies, including 8 trials and 4 observational studies where the platform performs all trial-related tasks (integral support: trial setup, monitoring, etc.) with more than 150 patients recruited since 2017 to these studies. In this manuscript, we provide baseline metrics for academic clinical trial performance that permit future comparisons. Conclusions: ECLIM-SEHOP facilitates Spanish children and adolescents diagnosed with cancer and blood disorders to access state-of-the-art diagnostic and therapeutic strategies
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