En el taller de Rubens: de la praxis a la ciencia. Análisis microestructural de preparaciones coloreadas con técnicas microscópicas (SEM/TEM)

Esta tesis forma parte del Proyecto de Investigación HUM2006-01847/ARTE, financiado por el Ministerio de Educación y Cultura. Ha sido realizado en la Facultad de Bellas Artes de Madrid, con la colaboración del Museo Nacional de Prado, y comprende el estudio histórico y análisis técnico comparativo de las preparaciones coloreadas sobre lienzo de dos cuadros de Rubens: “Retrato ecuestre del Duque de Lerma” (Madrid, 1603) y “Filopómenes reconocido por unos ancianos en Megara” (Amberes, 1609-1610); actualmente, la principal pinacoteca española conserva un importante número de obras del pintor, entre las que se cuentan los dos lienzos seleccionados. Pedro Pablo Rubens (1577-1640), es uno de los artistas flamencos más influyentes que dominó la pintura barroca europea del siglo XVII. Se dedicó prácticamente de forma exclusiva a la pintura y a la negociación política, alcanzando una elevada posición social y económica y un alto nivel cultural para la época. Su producción pictórica es muy amplia, reflejo de ello son las numerosas investigaciones que se han publicado a lo largo de los años. En el plano político se comprometió firmemente por alcanzar la paz en Europa; su convicción personal en el proyecto de renovación de la monarquía católica le llevó a emprender una intensa carrera diplomática en las cortes de Italia, Francia, Inglaterra, Holanda y, principalmente, España. Los dos viajes que realiza a Valladolid y Madrid (1603-04 y 1628-29), le permitieron, además, conocer la gran colección de arte de los Sitios Reales, y desarrollar una gran producción pictórica..

Salmonella enterica Serovar Typhimurium Exploits Inflammation to Modify Swine Intestinal Microbiota

Salmonella enterica serovar Typhimurium is an important zoonotic gastrointestinal pathogen responsible for foodborne disease worldwide. It is a successful enteric pathogen because it has developed virulence strategies allowing it to survive in a highly inflamed intestinal environment exploiting inflammation to overcome colonization resistance provided by intestinal microbiota. In this study, we used piglets featuring an intact microbiota, which naturally develop gastroenteritis, as model for salmonellosis. We compared the effects on the intestinal microbiota induced by a wild type and an attenuated S. Typhimurium in order to evaluate whether the modifications are correlated with the virulence of the strain. This study showed that Salmonella alters microbiota in a virulence-dependent manner. We found that the wild type S. Typhimurium induced inflammation and a reduction of specific protecting microbiota species (SCFA-producing bacteria) normally involved in providing a barrier against pathogens. Both these effects could contribute to impair colonization resistance, increasing the host susceptibility to wild type S. Typhimurium colonization. In contrast, the attenuated S. Typhimurium, which is characterized by a reduced ability to colonize the intestine, and by a very mild inflammatory response, was unable to successfully sustain competition with the microbiota.

Salmonella Typhimurium exploits inflammation to its own advantage in piglets

Salmonella Typhimurium (S. Typhimurium) is responsible for foodborne zoonotic infections that, in humans, induce self-limiting gastroenteritis. The aim of this study was to evaluate whether the wild-type strain S. Typhimurium (STM14028) is able to exploit inflammation fostering an active infection. Due to the similarity between human and porcine diseases induced by S. Typhimurium, we used piglets as a model for salmonellosis and gastrointestinal research. This study showed that STM14028 is able to efficiently colonize in vitro porcine mono-macrophages and intestinal columnar epithelial (IPEC-J2) cells, and that the colonization significantly increases with LPS pre-treatment. This increase was then reversed by inhibiting the LPS stimulation through LPS antagonist, confirming an active role of LPS stimulation in STM14028-intracellular colonization. Moreover, LPS in vivo treatment increased cytokines blood level and body temperature at 4 h post infection, which is consistent with an acute inflammatory stimulus, capable to influence the colonization of STM14028 in different organs and tissues. The present study proves for the first time that in acute enteric salmonellosis, S. Typhimurium exploits inflammation for its benefit in piglets.

Natural Bagaza virus infection in game birds in southern Spain

In late summer 2010 a mosquito born flavivirus not previously reported in Europe called Bagaza virus (BAGV) caused high mortality in red-legged partridges (Alectoris rufa) and ring-necked pheasants (Phasianus colchicus). We studied clinical findings, lesions and viral antigen distribution in naturally BAGV infected game birds in order to understand the apparently higher impact on red-legged partridges. The disease induced neurologic signs in the two galliform species and, to a lesser extent, in common wood pigeons (Columba palumbus). In red-legged partridges infection by BAGV caused severe haemosiderosis in the liver and spleen that was absent in pheasants and less evident in common wood pigeons. Also, BAGV antigen was present in vascular endothelium in multiple organs in red-legged partridges, and in the spleen in common wood pigeons, while in ring-necked pheasants it was only detected in neurons and glial cells in the brain. These findings indicate tropism of BAGV for endothelial cells and a severe haemolytic process in red-legged partridges in addition to the central nervous lesions that were found in all three species.