Transcriptomic analysis of the hepatic response to stress in the red cusk-eel (Genypterus chilensis): Insights into lipid metabolism, oxidative stress and liver steatosis

Indexación: Scopus.Teleosts exhibit a broad divergence in their adaptive response to stress, depending on the magnitude, duration, and frequency of stressors and the species receiving the stimulus. We have previously reported that the red cusk-eel (Genypterus chilensis), an important marine farmed fish, shows a physiological response to stress that results in increased skeletal muscle atrophy mediated by over-expression of components of the ubiquitin proteasome and autophagy-lysosomal systems. To better understand the systemic effects of stress on the red cusk-eel metabolism, the present study assessed the transcriptomic hepatic response to repetitive handling-stress. Using high-Throughput RNA-seq, 259 up-regulated transcripts were found, mostly associated with angiogenesis, gluconeogenesis, and triacylglyceride catabolism. Conversely, 293 transcripts were down-regulated, associated to cholesterol biosynthesis, PPARα signaling, fatty acid biosynthesis, and glycolysis. This gene signature was concordant with hepatic metabolite levels and hepatic oxidative damage. Moreover, the increased plasmatic levels of AST (aspartate aminotransferase), ALT (alanine aminotransferase) and AP (alkaline phosphatase), as well as liver histology suggest stress-induced liver steatosis. This study offers an integrative molecular and biochemical analysis of the hepatic response to handling-stress, and reveals unknown aspects of lipid metabolism in a non-model teleost.http://journals.plos.org/plosone/article?id=10.1371/journal.pone.017644

Evaluación preliminar sobre manejo del pastoreo en asociación gramínea-leguminosa.

Ganado de doble propósito-Ganadería doble propósit

Dinámicas socioecológicas y ecoturismo comunitario: Un análisis comparativo en el eje fluvial Guayabero-Guaviare

The effects of the ecotourism in the relationships between inhabitants and their environment are complex and multidimensional. To explore these effects, two community ecotourism initiatives in the Guaviare Province were comparatively analyzed. This territory has been historically affected by the armed conflict and today is given priority as a scenery for the peace construction. The analysis herein articulates approaches both from the political ecology and the socio-ecological systems and considers how important it is to understand the power relations emerging in community ecotourism contexts that, in turn, help to measure how this kind of tourism impacts the socio-ecological dynamics and the strategies by the peasant families who try to diversify their economies to made them sustainable. © 2018, Pontificia Universidad Javeriana. All rights reserved

Flux-cutting and flux-transport effects in type-II superconductor slabs in a parallel rotating magnetic field

The magnetic response of irreversible type-II superconductor slabs subjected to in-plane rotating magnetic field is investigated by applying the circular, elliptic, extended-elliptic, and rectangular flux-line-cutting criticalstate models. Specifically, the models have been applied to explain experiments on a PbBi rotating disk in a fixed magnetic field Ha, parallel to the flat surfaces. Here, we have exploited the equivalency of the experimental situation with that of a fixed disk under the action of a parallel magnetic field, rotating in the opposite sense. The effect of both the magnitude Ha of the applied magnetic field and its angle of rotation αs upon the magnetization of the superconductor sample is analyzed. When Ha is smaller than the penetration field HP, the magnetization components, parallel and perpendicular to Ha, oscillate with increasing the rotation angle. On the other hand, if the magnitude of the applied field, Ha, is larger than HP, both magnetization components become constant functions of α s at large rotation angles. The evolution of the magnetic induction profiles inside the superconductor is also studied

Single-phase five-level multilevel inverter based on a transistors six-pack module

This article introduces a single-phase five-level multilevel inverter based on six switches and two transformers. The proposed converter requires a single dc input source with low voltage. The disposition of switches makes it possible to build the converter with a transistors six-pack module off-the-shelves, traditionally used to build three-phase inverters, which simplifies the manufacturing process. The converter increases the voltage with two transformers; for that reason, it does not require an auxiliary step-up converter. The use of transformers (with the transformer’s turns ratio) allows for using the same topology for several input voltage levels. To verify the operation of the proposed multilevel inverter, a computer-based simulation was performed with PSIM, a software that considers parasitic components. The results show that the proposed converter can work properly

The fourth-order single-switch improved super-boost converter with reduced input current ripple

This paper introduces a new single switch DC-DC fourth-order boost converter. The proposed converter is the improved version of an existing converter known as the super-boost converter. The improved super-boost ISP converter achieves a smaller input current ripple than the super-boost converter when the same parameters in passive components are used. Conversely, smaller components can be used to achieve the same input current ripple, which leads to a compact and cheaper design. A comparative evaluation showed a reduction of 37.3% of stored energy in inductors to comply with a required input current ripple in comparison with the super-boost converter for a particular design. Experimental results are provided to corroborate this benefit of the ISB proposed topology

Sirolimus-eluting stent for the treatment of in-stent restenosis: a quantitative coronary angiography and three-dimensional intravascular ultrasound study

BACKGROUND: We have previously reported the safety and effectiveness of sirolimus-eluting stents for the treatment of de novo coronary lesions. The present investigation explored the potential of this technology to treat in-stent restenosis. METHODS AND RESULTS: Twenty-five patients with in-stent restenosis were successfully treated with the implantation of 1 or 2 sirolimus-eluting Bx VELOCITY stents in Sao Paulo, Brazil. Nine patients received 2 stents (1.4 stents per lesion). Angiographic and volumetric intravascular ultrasound (IVUS) images were obtained after the procedure and at 4 and 12 months. All vessels were patent at the time of 12-month angiography. Angiographic late loss averaged 0.07+/-0.2 mm in-stent and -0.05+/-0.3 mm in-lesion at 4 months, and 0.36+/-0.46 mm in-stent and 0.16+/-0.42 mm in-lesion after 12 months. No patient had in-stent or stent margin restenosis at 4 months, and only one patient developed in-stent restenosis at 1-year follow-up. Intimal hyperplasia by 3-dimensional IVUS was 0.92+/-1.9 mm(3) at 4 months and 2.55+/-4.9 mm(3) after 1 year. Percent volume obstruction was 0.81+/-1.7% and 1.76+/-3.4% at the 4- and 12-month follow-up, respectively. There was no evidence of stent malapposition either acutely or in the follow-up IVUS images, and there were no deaths, stent thromboses, or repeat revascularizations. CONCLUSION: This study demonstrates the safety and the potential utility of sirolimus-eluting Bx VELOCITY stents for the treatment of in-stent restenosis

A step-up converter with large voltage gain and low voltage rating on capacitors

Step-up converters are widely used in many applications, such as renewable energy generation with photovoltaic panels and fuel cell stacks. In many cases, the required voltage gain is larger for those applications than a traditional boost converter can achieve. Several large-voltage gain converters have been recently studied. This paper introduces a converter topology in which the voltage gain is larger than a traditional boost converter. The main advantages of the proposed topology are: (i) it provides a large voltage gain without the use of an extreme duty cycle; (ii) its capacitors require a smaller voltage to be sustained compared with other, similar state-of-the-art converters; (iii) the voltage among the ground input and output is not pulsating; and (iv) it can be synthesized with commercial, off-the-shelf half-bridge packed transistors. The proposed converter can be employed in different applications, such as distributed generation and microgrids. This paper presents the steady-state analysis of the proposed converter in the continuous conduction mode, a short comparison with similar topologies, and their voltage on capacitors. Computer-based simulation results are provided to verify the principle of the proposed converter in different operating conditions

Bioquímica y proteómica vegetal y agrícola

En la presente comunicación se resume lo que ha sido la actividad investigadora del grupo “Bioquímica y Proteómica Vegetal y Agrícola” (PAI AGR-164) en los últimos tres años (2005-2007). Nuestro interés y objetivo científico se ha centrando en el estudio de los cambios adaptativos y reacciones de defensa y de resistencia/tolerancia de las plantas a estreses de tipo biótico (hongos fitopatógenos y plantas parásitas) y abiótico (metales pesados, sequía). Dichos estudios se han llevado a cabo tanto con sistemas modelo (Arabidopsis thaliana y Medicago truncatula), como con especies de interés agronómico (garbanzo, girasol, guisante, maíz) o forestal (encina, alcornoque y pino). En los proyectos de investigación abordados se ha utilizado, en gran medida, una aproximación de proteómica, y también técnicas de bioquímica clásica y transcriptómica. La proteómica constituye, hoy en día, una línea prioritaria en cualquier investigación biológica, suministrando, en el área de la biología vegetal, y en combinación con las técnicas clásicas de bioquímica y las de transcriptómica, información relevante sobre diferentes aspectos básicos y aplicados relacionados con especies de interés agronómico y forestal, como es el de la respuesta a estreses, y la caracterización de genotipos (poblaciones, mutantes, líneas transgénicas). Además, hay aspectos, como el de las modificaciones postraduccionales, que sólo pueden ser abordados experimentalmente mediante una estrategia de proteómica. Nuestro grupo ha iniciado recientemente una nueva línea, dirigida a estudiar el proteoma redox en Arabidopsis y su implicación en la respuesta a patógeno