Estado de estrés oxidativo en el hígado graso experimental en ratones machos y su proyección sobre la funcionalidad hepática

En medicina veterinaria, el rol del estrés oxidativo (EO) en la producción y reproducción animal ha adquirido relevancia debido al deterioro de ambas funciones en animales con hepatoesteatosis o hígado graso (HG). Este estudio tuvo el objetivo de determinar si en el HG experimental causado por etionina en ratones machos NMRI adultos, se establecía un estado de EO hepático y se alteraba la función del hígado. Se utilizaron dos grupos de 10 animales: uno control y otro tratado con DL-etionina por vía intraperitoneal en dosis de 7,5 mg/20 g de peso corporal. La magnitud y características del HG fueron determinadas histológicamente y la cuantía del depósito graso hepático se estableció por la concentración de triglicéridos, análisis que corroboraron la generación de hepatoesteatosis en los machos inyectados con DL-etionina. Los productos de la degradación lipoperoxidativa, dienos conjugados (DC) y malondialdehído (MDA), indicadores de EO celular, fueron cuantificados por espectrofotometría, mediante su concentración en el homogeneizado hepático. El daño en la funcionalidad hepática se cuantificó por los niveles plasmáticos de la alanina aminotransferasa (ALT) y de la aspartato aminotransferasa (AST), mediante kits comerciales. La inducción de HG causó una elevación significativa de los DC: de 231,18 ± 15,53 µmoles/mg proteínas a 297,45 ± 23,10 mmoles/mg proteínas (P<0,05), así como del MDA: de 364,91 ± 17,73 nmoles/mg proteínas a 852,91 ± 55,26 nmoles/mg proteínas (P<0,001). En los ratones con HG, la actividad plasmática de las aminotransferasas aumentó significativamente: ALT de 59,40 ± 5,16 U/l a 169,86 ± 18,78 U/l (P<0,001) y AST de 158,35 ± 13,54 U/l a 241,93 ± 10,14 U/l (P<0,05). Estos resultados muestran que en el HG inducido por etionina en ratones machos NMRI se produce un estado de EO que podría ser responsable de la alteración en la funcionalidad hepática. In veterinary medicine the role of oxidative stress (OS) in animal production and reproduction has become important due to the alteration of both functions in animals with hepatosteatosis or fatty liver (FL). This study aimed to determine whether a state of hepatic OS was established in the experimental FL caused by ethionine in adult male mice NMRI, and whether liver function was altered. Two groups of 10 animals were used: one control and another treated with DL-ethionine intraperitoneally at 7.5 mg/20 g body weight. The magnitude and characteristics of FL were determined histologically and the amount of liver fat depot was established by the concentration of triglycerides. Both analysis corroborated generation of hepatosteatosis in males injected with DL-ethionine. Products from lipoperoxidative degradation (conjugated dienes (CD) and malondialdehyde (MDA), indicators of cellular OS, were quantified spectrophotometrically by its concentration in liver homogenate. Damage to liver function was measured by plasmatic levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), using commercial kits. The induction of FL caused a significant rise in CD from 231.18 ± 15.53 µmoles/mg protein to 297.45 ± 23.10 mmoles/mg protein (P<0.05), as well as the MDA: from 364.91 ± 17.73 nmoles/mg protein to 852.91 ± 55.26 nmoles/mg protein (P<0.001). In mice with FL aminotransferases plasmatic activity increased significantly: ALT of 59.40 ± 5.16 U/l from 169.86 ± 18.78 U/l (P<0.001) and AST from 158.35 ± 13.54 U/l to 241.93 ± 10.14 U/l (P<0.05). These results show that in ethionine-induced FL in male NMRI mice a state of OS is induced that could be responsible for the alteration in liver function

Modeling the Subsurface Structure of Sunspots

While sunspots are easily observed at the solar surface, determining their subsurface structure is not trivial. There are two main hypotheses for the subsurface structure of sunspots: the monolithic model and the cluster model. Local helioseismology is the only means by which we can investigate subphotospheric structure. However, as current linear inversion techniques do not yet allow helioseismology to probe the internal structure with sufficient confidence to distinguish between the monolith and cluster models, the development of physically realistic sunspot models are a priority for helioseismologists. This is because they are not only important indicators of the variety of physical effects that may influence helioseismic inferences in active regions, but they also enable detailed assessments of the validity of helioseismic interpretations through numerical forward modeling. In this paper, we provide a critical review of the existing sunspot models and an overview of numerical methods employed to model wave propagation through model sunspots. We then carry out an helioseismic analysis of the sunspot in Active Region 9787 and address the serious inconsistencies uncovered by \citeauthor{gizonetal2009}~(\citeyear{gizonetal2009,gizonetal2009a}). We find that this sunspot is most probably associated with a shallow, positive wave-speed perturbation (unlike the traditional two-layer model) and that travel-time measurements are consistent with a horizontal outflow in the surrounding moat.Comment: 73 pages, 19 figures, accepted by Solar Physic

7th Drug hypersensitivity meeting: part two

No abstract availabl

Geographical and temporal distribution of SARS-CoV-2 clades in the WHO European Region, January to June 2020

We show the distribution of SARS-CoV-2 genetic clades over time and between countries and outline potential genomic surveillance objectives. We applied three available genomic nomenclature systems for SARS-CoV-2 to all sequence data from the WHO European Region available during the COVID-19 pandemic until 10 July 2020. We highlight the importance of real-time sequencing and data dissemination in a pandemic situation. We provide a comparison of the nomenclatures and lay a foundation for future European genomic surveillance of SARS-CoV-2.Peer reviewe

The Athena X-ray Integral Field Unit: a consolidated design for the system requirement review of the preliminary definition phase

Instrumentatio

Parallel Hyperspectral Image Processing on Distributed Multi-Cluster Systems

Computationally efficient processing of hyperspectral image cubes can be greatly beneficial in many application domains, including environmental modeling, risk/hazard prevention and response, and defense/security. As individual cluster computers often cannot satisfy the computational demands of emerging problems in hyperspectral imaging, there is a growing need for distributed supercomputing using multicluster systems. A well-known manner of obtaining speedups in hyperspectral imaging is to apply data parallel approaches, in which commonly used data structures (e.g., the image cubes) are being scattered among the available compute nodes. Such approaches work well for individual compute clusters, but - due to the inherently large wide-area communication overheads - these are generally not applied in distributed multi-cluster systems. Given the nature of many algorithmic approaches in hyperspectral imaging, however, and due to the increasing availability of high-bandwidth optical networks, wide-area data parallel execution may well be a feasible acceleration approach. This paper discusses the wide-area data parallel execution of two realistic and state-of-the-art algorithms for endmember extraction in hyperspectral unmixing applications: automatic morphological endmember extraction and orthogonal subspace projection. It presents experimental results obtained on a real-world multicluster system, and provides a feasibility analysis of the applied parallelization approaches. The two parallel algorithms evaluated in this work had been developed before for single-cluster execution, and were not changed. Because no further implementation efforts were required, the proposed methodology is easy to apply to already available algorithms, thus reducing complexity and enhancing standardization. © 2011 Society of Photo-Optical Instrumentation Engineers (SPIE)

Retrieving sub-pixel land cover composition through an effective integration of the spatial, spectral and temporal dimensions of MERIS imagery

A computer code (acronym 5S) has been developed that allows estimation of the solar radiation backscattered by the Earth-surface-atmosphere system, as it is observed by a satellite sensor. Given the Lambertian ground reflectance, the apparent reflectance of the observed pixel is estimated by taking into account the effects of gaseous absorption, scattering by molecules and aerosols and, to some extent, inhomogeneity in the ground reflectance. The input parameters (observation geometry, atmosphere model, ground reflectance and spectral band) can be either selected from some proposed standard conditions (e.g. spectral bands of a satellite sensor) or user-defined. Besides the pixel apparent reflectance, the code provides the gaseous transmittance, the irradiance at the surface and the different contributions to the satellite signal according to the origin of the measured radiance. Some complementary results are also available; among others, benchmark calculations permit assessment of the code accuracy