87 research outputs found
Transporte electrogénico en el colon de ratas privadas de sodio : bloqueo de canales epiteliales versus inhibición de la NA, K-ATPASA
La privación dietaria de sodio estimula la secreción de aldosterona. En el colon de rata, la aldosterona elevada aumenta la absorción de Na+, pero además torna electrogénico el mecanismo de absorción (normalmente electroneutro). Dicho transporte electrogénico puede suprimirse mediante el bloqueo de los canales
epiteliales de Na+ en la membrana apical o la inhibición de la Na, KATPasa
de la membrana basolateral.
La absorción electrogénica de sodio está estrechamente acoplada al metabolismo aerobio, pero se desconoce si el bloqueo de los canales de Na+ reduce el
consumo de oxígeno en igual medida que la inhibición de la Na, K-ATPasa. Se obtuvieron preparados de mucosa aislada del colon distal de ratas alimentadas con una dieta hiposódica por 10 días. Se determinó simultáneamente la corriente
de cortocircuito y el consumo de oxígeno en condición basal y luego del bloqueo de canales de Na+ con amilorida (n=12) o de la Na, K-ATPasa con uabaína (n=12).
Ambos tratamientos redujeron la corriente de cortocircuito en igual medida (>80%), pero la reducción en el consumo de oxígeno fue mayor con uabaína que con
amilorida (p<0.03). Esto se debe probablemente a que la Na, KATPasa cumple otras funciones, además del transporte transepitelial de Na+, que son suprimidas por la
uabaína pero no por la amilorida.Dietary sodium deprivation stimulates aldosterone secretion. In the rat colon, high aldosterone levels increases Na+ absorption but also switches the mechanism of Na+
absorption from electroneutral to electrogenic. Such electrogenic transport may be suppressed by either epithelial Na+ channel blockade at the apical membrane or
Na, K-ATPase inhibition at the basolateral membrane. Electrogenic Na+ absorption is tightly coupled to aerobic metabolism, but it is not known whether epithelial Na+
channel blockade and Na, KATPase inhibition cause the same degree of reduction in epithelial oxygen consumption. Distal colon isolated mucosa preparations were
obtained from rats fed with a low sodium diet for 10 days. Short-circuit current and oxygen consumption were simultaneously measured in baseline condition and after either blocking epithelial Na+ channels with amiloride (n=12) or the Na, KATPase
with ouabain (n=12). Both treatments reduced short-circuit current to the same degree, but the reduction in oxygen consumption was larger with ouabain (p<0.03).
The difference may be due to the fact that Na, K-ATPase has other functions besides transepithelial Na+ transport, which are suppressed by ouabain but not by amiloride.Fil: Carra, Graciela E..
Universidad Nacional de Cuyo. Facultad de Ciencias MédicasFil: Galella, Flavia.
Universidad Nacional de Cuyo. Facultad de Ciencias MédicasFil: Widenberg, Johan.
Universidad Nacional de Cuyo. Facultad de Ciencias MédicasFil: Ibáñez, Jorge E..
Universidad Nacional de Cuyo. Facultad de Ciencias MédicasFil: Saraví, Fernando D..
Universidad Nacional de Cuyo. Facultad de Ciencias Médica
Ruptura esplénica posterior a colonoscopia: complicación infrecuente pero potencialmente letal
La Colonoscopia es el método diagnostico y terapéutico mas importante en la detección de lesiones tumorales del colon. Sin embargo la perforación y la hemorragia son las complicaciones más frecuentes aunque en un porcentaje bajo en los exámenes diagnósticos. Se han descrito complicaciones menos frecuente como neumomediastino, neumoretroperitoneo y ruptura de bazo. Nosotros presentamos un caso de lesión esplénica posterior a realización de colonoscopia en el servicio de Coloproctología del Hospital Militar Central, diagnosticado posterior a 48 horas tratado con manejo conservador. Se realiza revisión de la literatura encontrando la ruptura esplénica como causa infrecuente de dolor abdominal posterior a colonoscopia que puede ser potencialmente letal pero que requiere alto grado de sospecha para ser diagnosticada en forma temprana. La utilización de la tomografía computadorizada de Abdomen es el elemento diagnostico más importante, aunque no se ha utilizado como decisión terapéutica en el tratamiento conservador o con esplenectomía. El manejo conservador con seguimiento intrahospitalario, reanimación y antibioticoterapia se considera como opción terapéutica, pero la esplenectomía fue el tratamiento más utilizado en los casos encontrados. La sospecha clínica y diagnóstico temprano de estas lesiones son los elementos más importantes que pueden disminuir el riesgo de morbilidad y mortalidad por estas complicaciones raras en la colonoscopia pero que pueden ser letale
Dynamic Touch as Common Ground for Enactivism and Ecological Psychology
The main purpose of this article is to show that enactivism and ecological psychology share more aspects than is often recognized. Rather than debating about differences, commonalities between the approaches are illustrated with the example of dynamic touch. Dynamic touch is a form of touch that implies muscles and tendons and that allows the perception of hand-held objects that are wielded but not seen. Given that perceivers perform the wielding movements with effort, dynamic touch necessarily implies active exploration. The strength of dynamic touch as an example lies in the fact that it has been formalized and analyzed in detail at the level of the laws that govern the organism-environment system. The example provides empirically supported instantiations of sensorimotor contingencies, in enactivist terms, and of intentional exploration and information detection, in ecological terms. Moreover, dynamic touch is a practical example of the enactivist concepts of bringing-forth the world and sense-making. As a second purpose, we use the example of dynamic touch to clarify key concepts of the ecological approach. Specifically, we analyze the concepts of invariance and affordance, indicating the crucial difference between perceiving and actualizing affordances, and highlighting the importance of these concepts for the dialogue between enactivism and ecological psychology.2019-2
Height after side: Goalkeepers detect the vertical direction of association-football penalty kicks from the ball trajectory
The present research analyzes the relation between the height of penalty kicks in association football and (a) the probability that goalkeepers stop the ball, (b) the kinematics of the kicker, and (c) the movements of the goalkeeper. We re-analyzed movement registration data that were collected in an experiment (with professional and semi-professional players) that focused on the horizontal direction of the penalties (Lopes et al., 2014). We also digitized and analyzed regular videos of the goalkeepers that were recorded by Lopes et al. (2014) but not analyzed. The present research complements the current understanding of the penalty kick with three main observations. First, goalkeepers save penalties at middle heights more often than low and high penalties. Second, the height of penalties is predicted less clearly than their horizontal direction from the kinematics of penalty takers. Third, goalkeepers tend to initiate the horizontal component of the saving action before the penalty taker contacts the ball, but they initiate the vertical component of the action about 245 ms after the contact. Taken together, these results support the view that goalkeepers make the left-right decision at least partly focusing on the kinematics of the kicker, and that they dynamically decide the vertical aspects of the movement later, focusing on the ball trajectory.This research was supported by a grant from the Portuguese
Foundation for Science and Technology (SFRH/BD/60520/2009),
awarded to JL, and a grant from the Spanish Ministry of Economy
and Competitiveness (PSI2013-43742). DA was partly supported
by the Fundação para a Ciência e Tecnologia, under Grant
UIDB/00447/2020 to CIPER – Centro Interdisciplinar para o
Estudo da Performance Humana (unit 447)
Pedigree analysis of the Spanish grapevine cultivar 'Hebén'
The use of Single Nucleotide Polymorphism (SNP)
markers allows genetic identification and parentage
analysis of grapevine cultivars. Ancient cultivars like
'Hebén' were widely cultivated in the Iberian Peninsula
along its history and likely contributed to the origin of
varieties which are still cultivated today. The goal of
our study was to search for possible first-degree relationships between the female variety 'Hebén' and other
Iberian and Mediterranean cultivars. For this purpose,
we used a set of 261 SNP markers which allowed identifying 23 trios and 37 parent-offspring relationships supported by high overall likelihood ratios (LOD scores).
The results shed light on the relationships among several cultivars from Spain and Portugal, and demonstrated that 'Hebén' is a major founder of current varieties
in the Iberian Peninsula viticulture, and contributed to
spread the chlorotype A in this region.L. H. ZINELABIDINE was supported by a fellowship from the Agencia Española de Cooperación Internacional. J. CUNHA was supported by a Post-doctoral fellowship “Fundação para a Ciência e Tecnologia” (SFRH/BPD/ 74895/2010). LHZ and JC were supported by COST action FA1003 “East-West Collaboration for Grapevine Diversity Exploration and Mobilization of Adaptive Traits for Breeding”, from European Cooperation in the Field of Scientific and Technical Research, through the funding of short scientific missions at the ICVV.Peer Reviewe
Pedigree analysis of the Spanish grapevine cultivar Heben
Trabajo presentado en la Final Conference Progress in Vitis Vinifera diversity evaluation and use, celebrada en Lisboa del 7 al 9 de octubre de 2014.Cost action FA1003 - GRAPENET. East-West Collaboration for Grapevine Diversity Exploration and Mobilization of Adaptive Traits for Breeding.Several studies have shown that some varieties have had a large contribution in the
production of varieties in certain regions, like ‘Pinot’ and ‘Heunisch Weiss’ in France. Previous results had
pointed out that the old Spanish female variety ‘Hebén’, known as ‘Mourisco Branco’ in Portugal, could be
one of those varieties with a remarkable role in the Iberian Peninsula. This ancient winegrape cultivar was
already described in Spain in the 16th century as a white variety of grapevine producing large and sparse
bunches of grape with big seeds.Peer Reviewe
Cell death mechanisms in tumoral and non-tumoral human cell lines triggered by photodynamic treatments: apoptosis, necrosis and parthanatos
Cell death triggered by photodynamic therapy can occur through different mechanisms: apoptosis, necrosis or autophagy. However, recent studies have demonstrated the existence of other mechanisms with characteristics of both necrosis and apoptosis. These new cell death pathways, collectively termed regulated necrosis, include a variety of processes triggered by different stimuli. In this study, we evaluated the cell death mechanism induced by photodynamic treatments with two photosensitizers, meso-tetrakis (4-carboxyphenyl) porphyrin sodium salt (Na-H2TCPP) and its zinc derivative Na-ZnTCPP, in two human breast epithelial cell lines, a non-tumoral (MCF-10A) and a tumoral one (SKBR-3). Viability assays showed that photodynamic treatments with both photosensitizers induced a reduction in cell viability in a concentration-dependent manner and no dark toxicity was observed. The cell death mechanisms triggered were evaluated by several assays and cell line-dependent results were found. Most SKBR-3 cells died by either necrosis or apoptosis. By contrast, in MCF-10A cells, necrotic cells and another cell population with characteristics of both necrosis and apoptosis were predominant. In this latter population, cell death was PARP-dependent and translocation of AIF to the nucleus was observed in some cells. These characteristics are related with parthanatos, being the first evidence of this type of regulated necrosis in the field of photodynamic therapy
Grapevine cultivar "Alfrocheiro" or "Bruñal" plays a primary role in the relationship among iberian grapevines
The grapevine cultivar known in Portugal as 'Alfrocheiro', and in Spain as 'Bastardo Negro', 'Bruñal' or 'Baboso Negro', plays a central role in the genetic network of the Iberian Peninsula grapevine cultivars. Three sets of different molecular markers, SNPs, nSSRs and cpSSRs, revealed more than twenty parent-offspring links with this cultivar. 'Alfrocheiro' chlorotype is definitely Western European but their parents are still unknown. The distribution of the cultivar, their offspring as well as the two main co-parents direct to a geographic origin around the Portuguese and Spanish border. This cultivar and their progenies represent about 15 % of the total grapevine acreage in Portugal, stressing the importance of 'Alfrocheiro' in the Portuguese wine character.This research was supported by: IVV – Instituto da Vinha e do Vinho (Ministério da Agricultura e do Mar-MAM); Programa de Desenvolvimento Rural (PRODER - Ação 2.2.3.1. - PA
18621 - MAM) and J. CUNHA was supported by a Post-doctoral fellowship >Fundação para a Ciência e Tecnologia> (SFRH/BPD/74895/2010) and a short scientific mission in the ICVV was part of COST action, FA 1003 from European Cooperation in the Field of Scientific and Technical Research. L. H. ZINELABIDINE was supported by a fellowship from the Agencia Española de Cooperación Internacional and a short-term scientific mission from COST FA1003 >East-West Collaboration for Grapevine Diversity Exploration and Mobilization of Adaptive Traits for Breeding>.Peer Reviewe
Grapevine cultivar “Alfrocheiro” or “Bastardo Negro" plays a primary role in Iberian grapevine diversity
Trabajo presentado en la Final Conference Progress in Vitis Vinifera diversity evaluation and use, celebrada en Lisboa del 7 al 9 de octubre de 2014.Cost action FA1003 - GRAPENET. East-West Collaboration for Grapevine Diversity Exploration and Mobilization of Adaptive Traits for Breeding.The grapevine cultivar known in Portugal as ‘Alfrocheiro’, and in Spain as ’Bastardo
Negro’, ’Bruñal’ or ’Baboso Negro’, plays a central role in the genetic network of the Iberian Peninsula
grapevine cultivars. ‘Alfrocheiro’ was already identified as a progenitor of several cultivars either by SSRs
or by SNPs but until now it progenitors are unknown.Peer Reviewe
Restauración y manejo de pinares de pino carrasco tras incendio en el sureste de la Península Ibérica
En el contexto actual de cambio global y
en particular, de cambio climático, el régimen de
incendios en la Cuenca Mediterránea se está viendo
modificado. En el sureste de la Península Ibérica
Pinus halepensis es la especie arbórea principal de
las masas forestales. En este trabajo se ha realizado
una revisión sobre la evolución de las masas de pino
carrasco después de incendio, observando diferentes
comportamientos en su regeneración natural. Esta
regeneración no siempre está garantizada, dando
lugar a una elevada densidad de brinzales o bien una
ausencia total de los mismos pudiendo requerir una
restauración forestal. Ambos casos demandan un
seguimiento de la masa a corto, medio y largo plazo,
para mejorar su manejo post-incendio, y así
valorar qué tipo de tratamientos son precisos
llevar a cabo en cada momentoIn the current framework of climate
change, the Mediterranean Basin fire regime is being
modified. In the southeast of the Iberian Peninsula,
Pinus halepensis is the principal tree species of
forest stands. A revision of the post-fire Aleppo pine
stands evolution has been performed, showing
different behaviours in its natural regeneration.
Regeneration is not always guaranteed, promoting
whether a large regeneration or an absence of it
requiring forest restoration. Both cases need
monitoring in the short, medium and long term, in
order to improve its post-fire management, and
therefore assess which treatments are suitable to
carry out at each time
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