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1.
Sensors (Basel) ; 17(5)2017 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-28441330

RESUMEN

A telemetry system for real-time monitoring of the motions, position, speed and course of a ship at sea is presented in this work. The system, conceived as a subsystem of a radar cross-section measurement unit, could also be used in other applications as ships dynamics characterization, on-board cranes, antenna stabilizers, etc. This system was designed to be stand-alone, reliable, easy to deploy, low-cost and free of requirements related to stabilization procedures. In order to achieve such a unique combination of functionalities, we have developed a telemetry system based on redundant inertial and magnetic sensors and GPS (Global Positioning System) measurements. It provides a proper data storage and also has real-time radio data transmission capabilities to an on-shore station. The output of the system can be used either for on-line or off-line processing. Additionally, the system uses dual technologies and COTS (Commercial Off-The-Shelf) components. Motion-positioning measurements and radio data link tests were successfully carried out in several ships of the Spanish Navy, proving the compliance with the design targets and validating our telemetry system.

2.
Stem Cell Res ; 7(1): 1-16, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21530438

RESUMEN

Rex-1/Zfp42 displays a remarkably restricted pattern of expression in preimplantation embryos, primary spermatocytes, and undifferentiated mouse embryonic stem (ES) cells and is frequently used as a marker gene for pluripotent stem cells. To understand the role of Rex-1 in selfrenewal and pluripotency, we used Rex-1 association as a measure to identify potential target genes, and carried out chromatin-immunoprecipitation assays in combination with gene specific primers to identify genomic targets Rex-1 associates with. We find association of Rex-1 to several genes described previously as bivalently marked regulators of differentiation and development, whose repression in mouse embryonic stem (ES) cells is Polycomb Group-mediated, and controlled directly by Ring1A/B. To substantiate the hypothesis that Rex-1 contributes to gene regulation by PcG, we demonstrate interactions of Rex-1 and YY2 (a close relative of YY1) with Ring1 proteins and the PcG-associated proteins RYBP and YAF2, in line with interactions reported previously for YY1. We also demonstrate the presence of Rex-1 protein in both trophectoderm and Inner Cell Mass of the mouse blastocyst and in both ES and in trophectoderm stem (TS) cells. In TS cells, we were unable to demonstrate association of Rex-1 to the genes it associates with in ES cells, suggesting that association may be cell-type specific. Rex-1 might fine-tune pluripotency in ES cells by modulating Polycomb-mediated gene regulation.


Asunto(s)
Células Madre Embrionarias/fisiología , Regulación de la Expresión Génica , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Proteínas Represoras/metabolismo , Animales , Diferenciación Celular/genética , Línea Celular , Células Madre Embrionarias/metabolismo , Femenino , Genes Homeobox , Humanos , Ratones , Proteínas del Grupo Polycomb , Embarazo , Conejos , Proteínas Represoras/genética , Transfección
3.
Opt Express ; 18(15): 15876-86, 2010 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-20720970

RESUMEN

A surface integral equation (SIE) formulation is applied to the analysis of electromagnetic problems involving three-dimensional (3D) piecewise homogenized left-handed metamaterials (LHM). The resulting integral equations are discretized by the well-known method of moments (MoM) and solved via an iterative process. The unknowns are defined only on the interfaces between different media, avoiding the discretization of volumes and surrounding space, which entails a drastic reduction in the number of unknowns arising in the numerical discretization of the equations. Besides, the SIE-MoM formulation inherently includes the radiation condition at infinity, so it is not necessary to artificially include termination absorbing boundary conditions. Some 3D numerical examples are presented to confirm the validity and versatility of this approach on dealing with LHM, also providing some intuitive verifications of the singular properties of these amazing materials.

4.
Apoptosis ; 11(11): 1969-75, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17031491

RESUMEN

PURPOSE: One of the most relevant aspects in cell death regulation is the signalling of apoptosis by the serine/threonine kinases MAPKs. The aim of this study was to investigate the effects of TNF-alpha stimulation on MAPK activation, and the pro- or anti-apoptotic role of these kinases in LNCaP and PC3 cells. MATERIAL AND METHODS: Treatments were carried out using several TNF-alpha concentrations, as well as specific pharmacological inhibitors of MAPKs. Apoptosis rates were evaluated by DAPI staining and flow cytometry. MAPK phosphorylation/activation was measured by Western blot. RESULTS: TNF-alpha induced apoptosis in a dose-dependent manner in LNCaP but not in PC3 cells. The MAPK inhibitors revealed that the apoptotic rate in LNCaP cells increased significantly following p38 inhibition. The kinase inhibitors failed to cause changes in apoptosis in PC3 cells. CONCLUSIONS: The potentiation of apoptosis by p38 inhibition points to this kinase as a possible target for the treatment of androgen-dependent prostatic cancer.


Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias de la Próstata/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Antracenos/farmacología , Western Blotting , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Flavonoides/farmacología , Humanos , Imidazoles/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Masculino , Neoplasias de la Próstata/enzimología , Inhibidores de Proteínas Quinasas/farmacología , Piridinas/farmacología , Transducción de Señal
5.
Cancer Invest ; 24(2): 119-25, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16537179

RESUMEN

A comparative study of the products of the cell cycle control genes p53 (mutated form), p21, Rb (nonphosphorylated and phosphorylated form) and TGFbeta was performed by immunohistochemistry and Western blot, in benign breast disorders and breast cancer (in situ and infiltrating tumors). For the five proteins studied, the relative numbers of positively stained cells were higher in in situ carcinoma than in benign breast diseases. In infiltrating breast tumors, the relative numbers of positively stained cells were even higher than in in situ tumors except for the percentage of pRb immunostained cells, which decreased slightly in infiltrative tumors. For the other four proteins, the percentages of positively stained cases were similar to those found in in situ tumors. In the three groups of patients, TGFbeta immunoreaction appeared in the cytoplasm while immunoreactions to p53, p21, Rb, and pRb were found always in the nucleus except for p21 in in situ tumors, which showed cytoplasmic immunoreaction. Present results suggest that accumulation of mutated p53, cytoplasmic p21, and pRb in breast gland epithelium might be a crucial point in the development of in situ adenocarcinoma. In the infiltrating tumors, the expression of p21 in the nuclei and the decrease in pRb expression suggest an insufficient attempt to hinder cell proliferation.


Asunto(s)
Neoplasias de la Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Intraductal no Infiltrante/metabolismo , Proteínas de Ciclo Celular/biosíntesis , Transformación Celular Neoplásica/metabolismo , Adulto , Anciano , Western Blotting , Neoplasias de la Mama/patología , Neoplasias de la Mama/fisiopatología , Carcinoma Ductal de Mama/patología , Carcinoma Ductal de Mama/fisiopatología , Carcinoma Intraductal no Infiltrante/patología , Carcinoma Intraductal no Infiltrante/fisiopatología , Transformación Celular Neoplásica/patología , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/biosíntesis , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Proteína de Retinoblastoma/biosíntesis , Factor de Crecimiento Transformador beta/biosíntesis , Proteína p53 Supresora de Tumor/biosíntesis
6.
J Pathol ; 208(3): 401-7, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16369914

RESUMEN

It has been proposed that, among other cellular responses, TNF-alpha induces not only cell death, but also cell proliferation by activation of p38. It has also been reported that IL-1-alpha favours cell proliferation by p38 activation. The aim of the present study was to evaluate upstream (alpha-PAK, MEK-6) and downstream (Elk-1 and ATF-2) components of the p38 transduction pathway in normal prostate, benign prostatic hyperplasia (BPH), and prostate carcinoma (PC). Immunohistochemical and western blot analyses were performed in 20 samples of normal prostate, 47 samples of BPH, and 27 samples of PC. In all normal prostates, immunoreactivity for p-Elk-1 and p-ATF-2 was observed in epithelial cell nuclei, but no expression of alpha-PAK or MEK-6. In BPH, there was expression of alpha-PAK (cytoplasm) and MEK-6 (cytoplasm), while the proportions of lesions that were immunoreactive for p-Elk-1 (nucleus and cytoplasm) and p-ATF-2 (nucleus) decreased. In PC, the percentages of cells that were immunoreactive for alpha-PAK (cytoplasm) or MEK-6 (cytoplasm) rose slightly in comparison with BPH, while the percentages of cells that were immunoreactive for p-Elk-1 (nucleus and cytoplasm) or p-ATF-2 (nucleus and cytoplasm) were much higher than in BPH. It is concluded that overexpression of alpha-PAK, MEK-6, p38, p-Elk-1, and p-ATF-2 in BPH, and more intensely in PC, enhances cell proliferation. In BPH, such proliferation is triggered by IL-1 and in part counteracted by the TNF-alpha/AP-1 pathway, which promotes apoptosis. In PC, proliferation is triggered by IL-1 and TNF-alpha (the TNF-alpha/AP-1 pathway is diverted towards p38 activation). Since in a study of the same patients immunoexpression of IL-1alpha and IL-1RI was previously observed to be increased in PC, inhibition of p38 is a possible target for PC treatment, as this inhibition would both decrease IL-1-induced cell proliferation and increase TNF-alpha-induced cell death.


Asunto(s)
Carcinoma/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Neoplasias de la Próstata/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Factor de Transcripción Activador 2 , Anciano , Anciano de 80 o más Años , Western Blotting/métodos , Estudios de Casos y Controles , Proliferación Celular , Células Epiteliales/metabolismo , Humanos , Inmunohistoquímica/métodos , MAP Quinasa Quinasa 6/análisis , Masculino , Persona de Mediana Edad , Hiperplasia Prostática/metabolismo , Proteínas Serina-Treonina Quinasas/análisis , Proteína Elk-1 con Dominio ets/análisis , Quinasas p21 Activadas
7.
Histopathology ; 47(1): 82-9, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15982327

RESUMEN

AIMS: To characterize the expression pattern of IL-6 and its receptors (IL-6R(alpha) and gp130), to relate this pattern to bcl-2 and bax expression and to elucidate the effects on the proliferation/apoptosis equilibrium in benign conditions and in situ and infiltrating breast cancer. METHODS AND RESULTS: The immunoexpression of IL-6 and its receptors (IL-6R(alpha) and gp130), and their relationship with bcl-2 and bax proteins, were studied in in situ and infiltrating tumours and in benign breast lesions by means of Western blotting and immunohistochemistry. The percentages of samples positive for IL-6, bcl-2 and bax and their immunoreaction densities were higher in in situ carcinomas and infiltrating tumours than in benign lesions; although in in situ lesions were not so high as in infiltrating tumours, except for bax, whose immunoexpression was as weak as in benign conditions, resulting in a bcl-2/bax ratio higher than in infiltrating tumours. CONCLUSIONS: The high expression of IL-6 and its receptors in tumours might be related to the enhanced cell proliferation occurring in breast cancer. IL-6 could act by increasing bcl-2 expression and thus altering the proliferation/apoptosis balance toward neoplastic cell proliferation. The increased bax immunoreactivity observed only in infiltrating tumours, which was not so high as the increase in bcl-2 immunoreactivity, might be interpreted as an attempt to hinder cell proliferation.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias de la Mama/patología , Carcinoma in Situ/patología , Carcinoma Ductal de Mama/patología , Adolescente , Adulto , Anciano , Antígenos CD/análisis , Western Blotting , Neoplasias de la Mama/metabolismo , Carcinoma in Situ/metabolismo , Carcinoma Ductal de Mama/metabolismo , Receptor gp130 de Citocinas , Humanos , Inmunohistoquímica , Interleucina-6/análisis , Glicoproteínas de Membrana/análisis , Persona de Mediana Edad , Proteínas Proto-Oncogénicas c-bcl-2/análisis , Receptores de Interleucina-6/análisis , Proteína X Asociada a bcl-2
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