Miositis osificante progresiva: ultraestructura, bioquímica e histoquímica de músculo macroscópicamente sano

Se estudió un caso de miositis osificante progresiva en una niña de 13 años, a la cual se le tomó una muestra de músculo gastronecmio lateral, aparentemente no afectado, en el curso de una intervención quirúrgica ortopédica. La muestra se procesó mediante métodos histológicos, histoquímicos, bioquímicos, inmunocitoquímicos y ultraestructurales. Se encontró un predominio de fibras musculares tipo I (83%) con alta capacidad oxidativa y baja capacidad glicolítica. Las fibras del tipo II eran pequeñas (área promedio 2.084 Um2 ) y mostraron otros signos de atrofia al examen ultraestructural. La densidad capilar fue relativamente alta, (573) siendo normal el índice capilar/fibra (1,76). Sin embargo, algunos capilares se mostraron engrosados y con la luz ocluida, con la tinción de amilasa-PAS, lo cual fue corroborado con la microscopía electrónica, donde se vio la membrana basal engrosada, e inclusive algunos capilares totalmente degenerados. No se encontró reacción de inmunofluorescencia con las globulinas anti-IgG ni anti-IgM en los cortes de músculo. El espacio intersticial se encontró agrandado. Se concluye que no hay evidencias de la participación de un mecanismo autoinmune en la miositis osificante progresiva, que existe un daño capilar y alteración de las fibras musculares, aún en el músculo que no manifiesta a simple vista proceso de osificación.During an orthopedic operation a sample of the apparently normal lateral gastronecmius muscle was taken from a 13 year old female patient affected by myositis ossificans progressiva. The muscle sample was analyzed by light, electron and fluorescence microscopy, and some enzymes were assayed. Muscle fibers were classified by the adenosintriphosphatase reaction. The percentage of type I fiber was high (83%). Atrophy was found in type II fibers as shown by small mean area (2.084 Um2 ) and some ultrastructural features as infoldings of the sarcolemma. Capillary density was high (573 capillaries/mm2 ), and capillaries per fiber index was normal (1.76), as were oxidative enzymes. However many capillaries were occluded, with thick basal membrane and abnormal endothelial cells and pericytes. No immunofluorescence was found with anti IgG or anti IgM in the muscle fibers. Intersticial spaces in the cross section of the muscle were enlarged. In conclusion, no evidence of autoimmune involvement was found in myositis ossificans progressiva, but alteracions of capillaries and muscle fibers were found in a muscle apparently not affected yet by the ossification process

Relacion entre el hábito de crecimiento y los componentes del rendimiento en fríjol (Phaseolus vulgaris L.).

Con el fin de conocer la relación entre los diferentes componentes del rendimiento en progenies de cruzamiento, de variedades volubles por arbustivas, se hicieron 4 cruzamientos. En las progenies segregantes se seleccionaron lineas arbustivas, lineas con guía corta y con guía larga. La F5 y F6 de estas selecciones se sembraron en experimentos replicados y se estudio: número de vainas por plantas, número de granos por vainas, tamaño de la semilla y rendimiento por planta. Las progenies con guía corta o larga mostraron mayor rendimiento que las progenies sin guía en 3 de los 4 cruzamientos estudiados. Esta diferencia de rendimiento fué debida al mayor número de granos que tenían las progenies con guía como resultado de un mayor número de vainas y granos por vaina. El cruzamiento cuyas progenies no mostraron diferencias en rendimientos en los tres hábitos de crecimiento, tampoco mostró diferencias en el promedio de los componentes. Las selecciones arbustivas mostraron aumento en el número de vainas sobre el promedio del padre arbustivo. Sin embargo, este aumento no produjó incrementos en rendimietos sino en el cruzamiento Pajarito chileno x Japón 6. Las selecciones con guía mostraron promedios inferiores al padre voluble en rendimiento, número de granos por vaina y número de vainas por planta en todos los casos. Si las variedades volubles son más rendidoras que las arbustivas, su rendimiento podría mejorarse mediante cruzamientos con otras variedades volublesFríjol-Phaseolus vulgari

Numerical evidence for `multi-scalar stars'

We present a class of general relativistic soliton-like solutions composed of multiple minimally coupled, massive, real scalar fields which interact only through the gravitational field. We describe a two-parameter family of solutions we call ``phase-shifted boson stars'' (parameterized by central density rho_0 and phase delta), which are obtained by solving the ordinary differential equations associated with boson stars and then altering the phase between the real and imaginary parts of the field. These solutions are similar to boson stars as well as the oscillating soliton stars found by Seidel and Suen [E. Seidel and W.M. Suen, Phys. Rev. Lett. 66, 1659 (1991)]; in particular, long-time numerical evolutions suggest that phase-shifted boson stars are stable. Our results indicate that scalar soliton-like solutions are perhaps more generic than has been previously thought.Comment: Revtex. 4 pages with 4 figures. Submitted to Phys. Rev.

Monostable controllers for adaptive behavior

Recent artificial neural networks for machine learning have exploited transient dynamics around globally stable attractors, inspired by the properties of cortical microcolumns. Here we explore whether similarly constrained neural network controllers can be exploited for embodied, situated adaptive behaviour. We demonstrate that it is possible to evolve globally stable neurocontrollers containing a single basin of attraction, which nevertheless sustain multiple modes of behaviour. This is achieved by exploiting interaction between environmental input and transient dynamics. We present results that suggest that this globally stable regime may constitute an evolvable and dynamically rich subset of recurrent neural network configurations, especially in larger networks. We discuss the issue of scalability and the possibility that there may be alternative adaptive behaviour tasks that are more ‘attractor hungry’

MicroRNA-129-5p is regulated by choline availability and controls EGF receptor synthesis and neurogenesis in the cerebral cortex

Choline availability modulates neurogenesis and cerebral cortex development through the regulation of neural progenitor cell (NPC) proliferative and differentiation capacity. In this study, we demonstrated that cortical NPC self-renewal is controlled by choline via the expression of a microRNA (miR-129-5p), whose role in the developing brain has not been examined, and which, in turn, inhibits synthesis of the epidermal growth factor receptor (EGFR) protein. Specifically, we found that low choline (LC) availability led to the upregulation of miR-129-5p expression in cortical NPCs in vitro and in vivo, causing the downregulation of EGFR and thereby disrupting NPC self-renewal and cortical neurogenesis. Furthermore, in response to LC availability, methylation potential (the S-adenosylmethionine:S-adenosylhomocysteine ratio) in the developing brain was reduced. Restoring methylation potential in LC cortical NPCs led to the re-establishment of normal miR-129-5p expression. We concluded that inhibiting miR-129-5p function and restoring EGFR protein levels in vivo is sufficient to reverse LC-induced defects in cortical NPC self-renewal. For the first time, to our knowledge, we have identified the molecular links that explain how a change in the availability of the diet metabolite choline impacts the essential cellular processes underlying brain development

Apple pomace powder as natural food ingredient in bakery jams

The aim of the present study was to investigate whether apple pomace powder produced by a simple drying method is suitable for replacing pectin in bakery jam products. Rheological properties of bakery jams were tested by oscillatory tests using amplitude sweep method. Apple pomace addition decreased gel strength and stability of bakery jams, while 12-month storage increased the gel strength of samples. Based on our results, dried apple pomace powder seems to be suitable to replace pectin up to 40% without changing rheological properties of bakery jams

Green function techniques in the treatment of quantum transport at the molecular scale

The theoretical investigation of charge (and spin) transport at nanometer length scales requires the use of advanced and powerful techniques able to deal with the dynamical properties of the relevant physical systems, to explicitly include out-of-equilibrium situations typical for electrical/heat transport as well as to take into account interaction effects in a systematic way. Equilibrium Green function techniques and their extension to non-equilibrium situations via the Keldysh formalism build one of the pillars of current state-of-the-art approaches to quantum transport which have been implemented in both model Hamiltonian formulations and first-principle methodologies. We offer a tutorial overview of the applications of Green functions to deal with some fundamental aspects of charge transport at the nanoscale, mainly focusing on applications to model Hamiltonian formulations.Comment: Tutorial review, LaTeX, 129 pages, 41 figures, 300 references, submitted to Springer series "Lecture Notes in Physics

Dark Matter and Fundamental Physics with the Cherenkov Telescope Array

The Cherenkov Telescope Array (CTA) is a project for a next-generation observatory for very high energy (GeV-TeV) ground-based gamma-ray astronomy, currently in its design phase, and foreseen to be operative a few years from now. Several tens of telescopes of 2-3 different sizes, distributed over a large area, will allow for a sensitivity about a factor 10 better than current instruments such as H.E.S.S, MAGIC and VERITAS, an energy coverage from a few tens of GeV to several tens of TeV, and a field of view of up to 10 deg. In the following study, we investigate the prospects for CTA to study several science questions that influence our current knowledge of fundamental physics. Based on conservative assumptions for the performance of the different CTA telescope configurations, we employ a Monte Carlo based approach to evaluate the prospects for detection. First, we discuss CTA prospects for cold dark matter searches, following different observational strategies: in dwarf satellite galaxies of the Milky Way, in the region close to the Galactic Centre, and in clusters of galaxies. The possible search for spatial signatures, facilitated by the larger field of view of CTA, is also discussed. Next we consider searches for axion-like particles which, besides being possible candidates for dark matter may also explain the unexpectedly low absorption by extragalactic background light of gamma rays from very distant blazars. Simulated light-curves of flaring sources are also used to determine the sensitivity to violations of Lorentz Invariance by detection of the possible delay between the arrival times of photons at different energies. Finally, we mention searches for other exotic physics with CTA.Comment: (31 pages, Accepted for publication in Astroparticle Physics