Impact of a Multichannel Blocker in Attenuating Intramyocardial Artery Remodeling in Hypertensive Rats through Increased Nitric Oxide Bioavailability.

Dronedarone is recommended for the treatment of atrial fibrillation. However, we do not know its effect on vascular remodeling. This study was designed to assess whether dronedarone has the potential to improve the intramyocardial artery remodeling induced by chronic hypertension. Ten-month-old male spontaneously hypertensive rats (SHR) were randomly assigned to receive dronedarone (100mg/kg) or vehicle. Age-matched maleWistar-Kyoto rats served as controls. After 14 days of treatment, we studied the structure (geometry and fibrosis) of the intramyocardial artery using histological analysis. Nitric oxide (NO) in plasma was analyzed. In the untreated SHR, we observed a significant increase in external diameter, lumen diameter, wall width, cross-sectional area, and collagen volume density, as was expected in the experimental model. Dronedarone induced a significant decrease in wall width, cross-sectional area, and collagen volume density in SHR-D in comparison with untreated SHR. The values obtained in SHR-D were similar in the WKY control group. We found significantly higher NO levels in plasma in SHR-D than in untreated SHR. Dronedarone improves the intramyocardial artery remodeling induced by chronic hypertension in SHR through increased nitric oxide bioavailability.post-print459 K

Involució de la condició física per l'envelliment

El percentatge de població de gent gran s’està incrementant a Espanya. L’envelliment produeix una involució de les capacitats físiques, la qual cosa origina un deteriorament de l’estat físic i una reducció de la funcionalitat. Aquests fets condicionen greus problemes de salut pública per l’aparició de malalties degeneratives, amb el consegüent cost econòmic per al seu tractament. A mesura que l’edat avança es produeix una pèrdua de força de cames i força de braços, un descens no constant del VO2màx i una reducció progressiva no lineal i específica per articulació i moviment articular de la flexibilitat. A més, en persones grans els trastorns freqüents d’equilibri alteren el patró de la marxa. I finalment es produeixen modificacions substancials de la composició corporal amb disminució de la massa lliure de greix, fet que condiciona un descens de la despesa energètica en repòs i un increment de la massa greix

Involución de la condición física por el envejecimiento

El porcentaje de población mayor se está incrementando en España. El envejecimiento produce una involución de las capacidades físicas, lo que origina un deterioro del estado físico y una reducción de la funcionalidad. Estos hechos condicionan graves problemas de salud pública por la aparición de enfermedades degenerativas con el consiguiente coste económico para su tratamiento. Conforme avanza la edad se produce una pérdida de fuerza de piernas y fuerza de brazos, un descenso no constante del VO2máx y una reducción progresiva no lineal y específica por articulación y movimiento articular de la flexibilidad. Además, en personas mayores los frecuentes trastornos de equilibrio alteran el patrón de la marcha. Y por último se producen modificaciones sustanciales de la composición corporal con disminución de la masa libre de grasa, lo que condiciona un descenso del gasto energético en reposo y el incremento de la masa grasa

Reef-associated depositional environments in the lowermost Cretaceous facies (Berriasian) from the Eastern Prebetic domain (South-Iberian Palaeomargin, SE Spain)

The Berriasian carbonate successions cropping out in the shallow-water platform of the easternmost Prebetic Domain (SE Spain) involve reef-associated environments including a diverse epibiota with diceratid representatives unreported so far. Interpretation of different sub-environments suggests a proximal-distal shallow platform transect. In the shallowest nearshore environment, high energy conditions are recorded, with fine-grained bioclasts interbedded with episodes with black pebbles. Subsequently, a more restricted intra-platform environment is represented by oncoidal rudstones with benthic foraminifera, photophilic microencrusters, microbial-type coatings, mud mounds and a rich record of epibenthic biota preserved in life position (diceratid patches, stromatoporoids, and a diverse coral assemblage). This association points to relatively stable and restrictive low-energy conditions in a proximal shallow-water subtidal environment below the fair-weather wave base. Distally, a deeper, opener setting is established. Here, phaceloid and thin-laminated corals are preserved in life position in a calpionellid-rich matrix typifying a mesophotic reefal complex with clear open marine influence. Biostratigraphical analysis performed mainly on benthic foraminifera, algae, diceratids, and coral representatives allows to specify a Berriasian age for these facies. New occurrence data are also reported, such as the oldest record of the coral genus Floriastrea worldwide. The highly diverse coral assemblages reveal a species-level taxonomic divergence in relation with taxa from the same biochore and palaeogeographical domain, supporting the endemic condition for this fauna. The first report of diceratids in the Eastern Prebetic around the J/C transition evokes Heterodiceras as possible precursor of the Cretaceous rudist build-ups developed in the Urgonian platforms in the Prebetic Domain.This research is a contribution to the P18-RT-4074 project, and to the Research Group VIGROB-167 (University of Alicante)

Biological insertion of computationally designed short transmembrane segments

The great majority of helical membrane proteins are inserted co-translationally into the ER membrane through a continuous ribosome-translocon channel. The efficiency of membrane insertion depends on transmembrane (TM) helix amino acid composition, the helix length and the position of the amino acids within the helix. In this work, we conducted a computational analysis of the composition and location of amino acids in transmembrane helices found in membrane proteins of known structure to obtain an extensive set of designed polypeptide segments with naturally occurring amino acid distributions. Then, using an in vitro translation system in the presence of biological membranes, we experimentally validated our predictions by analyzing its membrane integration capacity. Coupled with known strategies to control membrane protein topology, these findings may pave the way to de novo membrane protein design

Mathematical modelling of neural processes within the oculomotor system

It is presented a mathematical model of the oculomotor plant, based on experimental data in cats. The system that generates, from the neuronal processes at the motoneuron, the control signals to the eye muscles that moves the eye. In contrast with previous models, that base the eye movement related motoneuron behavior on a first order linear differential equation, non-linear effects are described: A dependency on the eye angular position of the model parameters

Does the epiphyseal cartilage of the long bones have one or two ossification fronts?

[Abstract] Epiphyseal cartilage is hyaline cartilage tissue with a gelatinous texture, and it is responsible for the longitudinal growth of the long bones in birds and mammals. It is located between the epiphysis and the diaphysis. Epiphyseal cartilage also is called a growth plate or physis. It is protected by three bone components: the epiphysis, the bone bar of the perichondrial ring and the metaphysis. The epiphysis, which lies over the epiphyseal cartilage in the form a cupola, contains a juxtaposed bone plate that is near the epiphyseal cartilage and is in direct contact with the epiphyseal side of the epiphyseal cartilage. The germinal zone corresponds to a group of cells called chondrocytes. These chondrocytes belong to a group of chondral cells, which are distributed in rows and columns; this architecture is commonly known as a growth plate. The growth plate is responsible for endochondral bone growth. The aim of this study was to elucidate the causal relationship between the juxtaposed bone plate and epiphyseal cartilage in mammals. Our hypothesis is that cells from the germinal zone of the epiphyseal side of the epiphyseal cartilage are involved in forming a second ossification front that is responsible for the origin of the juxtaposed bone plate. We report the following: (a) The juxtaposed bone plate has a morphology and function that differs from that of the epiphyseal trabeculae; (b) on the epiphyseal edge of the epiphyseal cartilage, a new ossification front starts on the chondrocytes of the germinal area, which forms the juxtaposed bone plate. This ossification front is formed by chondrocytes from the germinal zone through a process of mineralisation and ossification, and (c) the process of mineralisation and ossification has a certain morphological analogy to the process of ossification in the metaphyseal cartilage of amphibians and differs from the endochondral ossification process in the metaphyseal side of the growth plate. The close relationship between the juxtaposed bone plate and the epiphyseal cartilage, in which the chondrocytes that migrate from the germinal area play an important role in the mineralisation and ossification process of the juxtaposed bone plate, supports the hypothesis of a new ossification front in the epiphyseal layer of the epiphyseal plate. This hypothesis has several implications: (a) epiphyseal cartilage is a morphological entity with two different ossification fronts and two different functions, (b) epiphyseal cartilage may be a morphological structure with three parts: perichondrial ring, metaphyseal ossification front or growth plate, and epiphyseal ossification front, (c) all disease (traumatic or dysplastic) that affects some of these parts can have an impact on the morphology of the epiphyseal region of the bone, (d) there is a certain analogy between metaphyseal cartilage in amphibians and mammalian epiphyseal cartilage, although the former is not responsible for bone growth, (e) comparative histological and anatomy studies are also warranted, to shed light on the phylogenetic study of epiphyseal cartilage throughout the changes that occur in the animal species