Registro automático de imágenes de bandas espectrales alejadas

Se presentan nuevos métodos para el registro de imágenes de bandas espectrales alejadas. El conjunto de transofrmaciones candidatas para el registro de las imágenes se determina mediante el casamiento de estructuras formadas por segmentos lineales rectos detectados en los bordes extraídos de las imágenes. Posteriormente se define un criterio para obtener la transformación de registro óptima del conjunto de trasnformaciones candidatas. Se presenta también dos métodos diferents para la evaluación de los procedimientos de registro desarrollados. El primero se basa en la descomposición de Gabor, y el segundo en la determinación del campo vectorial de desplazamientos locales asociados al desregistro. Finalmente se describen y analizan los resultados de la aplicación de los métodos de registro a varios tipos de imágenes (en particular, visible-visible, visible-IR y visibles-SAR), y se presentan otras posibles aplciaciones.Depto. de ÓpticaFac. de Ciencias FísicasTRUEpu

Caspase-3-mediated cleavage of p65/RelA results in a carboxy-terminal fragment that inhibits IκBα and enhances HIV-1 replication in human T lymphocytes

<p>Abstract</p> <p>Background</p> <p>Degradation of p65/RelA has been involved in both the inhibition of NF-κB-dependent activity and the onset of apoptosis. However, the mechanisms of NF-κB degradation are unclear and can vary depending on the cell type. Cleavage of p65/RelA can produce an amino-terminal fragment that was shown to act as a dominant-negative inhibitor of NF-κB, thereby promoting apoptosis. However, the opposite situation has also been described and the production of a carboxy-terminal fragment that contains two potent transactivation domains has also been related to the onset of apoptosis. In this context, a carboxy-terminal fragment of p65/RelA (ΔNH₂p65), detected in non-apoptotic human T lymphocytes upon activation, has been studied. T cells constitute one of the long-lived cellular reservoirs of the human immunodeficiency virus type 1 (HIV-1). Because NF-κB is the most important inducible element involved in initiation of HIV-1 transcription, an adequate control of NF-κB response is of paramount importance for both T cell survival and viral spread. Its major inhibitor IκBα constitutes a master terminator of NF-κB response that is complemented by degradation of p65/RelA.</p> <p>Results and conclusions</p> <p>In this study, the function of a caspase-3-mediated carboxy-terminal fragment of p65/RelA, which was detected in activated human peripheral blood lymphocytes (PBLs), was analyzed. Cells producing this truncated p65/RelA did not undergo apoptosis but showed a high viability, in spite of caspase-3 activation. ΔNH₂p65 lacked most of DNA-binding domain but retained the dimerization domain, NLS and transactivation domains. Consequently, it could translocate to the nucleus, associate with NF-κB1/p50 and IκBα, but could not bind -κB consensus sites. However, although ΔNH₂p65 lacked transcriptional activity by itself, it could increase NF-κB activity in a dose-dependent manner by hijacking IκBα. Thus, its expression resulted in a persistent transactivation activity of wild-type p65/RelA, as well as an improvement of HIV-1 replication in PBLs. Moreover, ΔNH₂p65 was increased in the nuclei of PMA-, PHA-, and TNFα-activated T cells, proving this phenomenon was related to cell activation. These data suggest the existence of a novel mechanism for maintaining NF-κB activity in human T cells through the binding of the carboxy-terminal fragment of p65/RelA to IκBα in order to protect wild-type p65/RelA from IκBα inhibition.</p

Approaches to Automatic Seabed Classification

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Automatic Target Recognition in Synthetic Aperture Sonar Images Based on Geometrical Feature Extraction

This paper presents a new supervised classification approach for automated target recognition (ATR) in SAS images. The recognition procedure starts with a novel segmentation stage based on the Hilbert transform. A number of geometrical features are then extracted and used to classify observed objects against a previously compiled database of target and non-target features. The proposed approach has been tested on a set of 1528 simulated images created by the NURC SIGMAS sonar model, achieving up to 95% classification accuracy

Molecular mechanisms involved in HIV latency and implications for HIV treatment and eradication

The aim of this presentation is to review the molecular mechanisms necessary for the establishment of HIV-1 latency, their relationship with different cellular and anatomic reservoirs, as well as the current treatment strategies targeting viral persistence in latent reservoirs, their main limitations and future perspectives.S

Basal shuttle of NF-κB/IκBα in resting T lymphocytes regulates HIV-1 LTR dependent expression

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Modifications in host cell structure and functions mediated by Tat intracellular expression are greatly dependent on the second exon

1 page.-- Poster presentation.Peer reviewe