360 research outputs found

    Insuficiencia venosa cerebroespinal crónica y esclerosis múltiple: revisión y actualización del tema

    Get PDF
    The aetiology of multiple sclerosis remains unknown at the present time, although the most likely explanation is that it has an autoimmune inflammatory origin. During the history of this disease a vascular pathophysiology was once proposed, and it has recently re-emerged as a result of the work by Paolo Zamboni with the name of 'chronic cerebrospinal venous insufficiency'. Following this hypothesis, Zamboni puts forward a curative treatment for multiple sclerosis by means of endovascular treatment of the internal jugular vein and the azygos vein. However, several teams have attempted to replicate his findings without success. In this review, we offer a chronological description of the studies carried out by Zamboni and the later attempts to replicate his work. Our main conclusion is that, given the results we currently have available, we should be cautious and, for the time being, it would be advisable not to recommend the systematic use of this treatment for our patients

    Utilidad de las secuencias potenciadas en susceptibilidad paramagnética (SWI) para diferenciar crisis somestésicas de accidentes isquémicos transitorios en un paciente con angiopatía amiloide cerebral

    Get PDF
    Background. Cerebral amyloid angiopathy (CAA) is characterized by the deposit of β-amyloid on the walls of small and medium-sized arteries of the cerebral cortex and leptomeninges causing cerebral bleeding. Clinical presentations may include transient neurological events for which differential diagnosis can be difficult. Case report. We report a subject with a medical history of recent stroke who presented somesthetic seizures mimicking transient ischemic attacks owing to CAA microbleeding. Antiplatelet treatment was reduced and after lamotrigine was commenced the episodes disappeared. Susceptibility-weighted magnetic resonance imaging was very helpful for diagnosis (SWI-MRI). Conclusions. CAA microbleeding can be manifested in the form of seizures mimicking focal transient sensitive neurological deficits that can be erroneously attributed to cerebral ischemia. The present case report suggests that, despite the presence of a past medical history of strokes, neurologists should consider CAA microbleeding as a possible cause of pseudo-transient ischemic attacks. High-resolution neuroimaging including SWIMRI imaging can be helpful in identifying cortical microbleedings. In this way, the start or increase of antiplatelet treatment can be avoided, and the risk of potentially fatal complications minimize

    Estimating evaporation from a wet grassland

    Get PDF
    International audienceWet grasslands are being restored across the UK and Europe to reinstate their high biodiversity following over 50 years of drainage and conversion to arable agriculture. The water balance of many wet grasslands is dominated by precipitation and evaporation and it is essential to quantify evaporation rates to understand the hydrological functioning of wetlands and the implications for water resources in catchments where wetlands are being restored. This paper considers data from direct measurements of evaporation from the Pevensey Levels wet grassland using the eddy correlation method. Equations are derived to predict actual evaporation using meteorological data on the site or from standard meteorological station observations. It was found that evaporation could be estimated reliably from meteorological variables, such as wind speed, temperature and humidity and by water availability. It was also found that when water availability is high, evaporation is high and may exceed reference evaporation values, raising questions over the deployment of the two-step Penman-Monteith model unless reliable crop coefficients and relative evaporation figures can be determined

    Transcranial Electrical Stimulation Accelerates Human Sleep Homeostasis

    Full text link
    The sleeping brain exhibits characteristic slow-wave activity which decays over the course of the night. This decay is thought to result from homeostatic synaptic downscaling. Transcranial electrical stimulation can entrain slow-wave oscillations (SWO) in the human electro-encephalogram (EEG). A computational model of the underlying mechanism predicts that firing rates are predominantly increased during stimulation. Assuming that synaptic homeostasis is driven by average firing rates, we expected an acceleration of synaptic downscaling during stimulation, which is compensated by a reduced drive after stimulation. We show that 25 minutes of transcranial electrical stimulation, as predicted, reduced the decay of SWO in the remainder of the night. Anatomically accurate simulations of the field intensities on human cortex precisely matched the effect size in different EEG electrodes. Together these results suggest a mechanistic link between electrical stimulation and accelerated synaptic homeostasis in human sleep

    No evidence that selection for egg production persistency causes loss of bone quality in laying hens

    Get PDF
    ERANET grant BBSRC BB/M028291/1Swedish Research Council Formas 2014-01840ARN (Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria) 291815European Cooperation in Science and Technology (COST) CA15224UK Research & Innovation (UKRI) Biotechnology and Biological Sciences Research Council (BBSRC) BB/P013759/

    Monitorización con vídeo-EEG y ECG simultáneo para el diagnóstico diferencial de trastornos de conciencia transitorios. A propósito de un caso

    Get PDF
    We present the case of a 36 year-old woman, with history of transient consciousness disorders with vegetative state, interpreted as epileptic crises and treated with valproate for two years. After nine asymptomatic years, they reappeared associated with migraine, vomiting and some generalized convulsions. Electroencephalogram and cerebral magnetic resonance turned out normal, and treatment with zonisamide was started, without beneficial results. Later cardiological studies objectified a blockage of the left branch that coincided with dizziness. The study was completed with Video-EGG monitoring, where there was an episode that showed temporary right epileptiform activity, with a diagnosis established of focal epilepsy of unknown cause. At present, she remains asymptomatic with oxycarbazepine

    A new primitive Neornithischian dinosaur from the Jurassic of Patagonia with gut contents

    Get PDF
    We describe a new species of an ornithischian dinosaur, Isaberrysaura mollensis gen. et sp. nov. The specimen, consisting in an almost complete skull and incomplete postcranium was collected from the marine-deltaic deposits of the Los Molles Formation (Toarcian-Bajocian), being the first reported dinosaur for this unit, one of the oldest from Neuquén Basin, and the first neornithischian dinosaur known from the Jurassic of South America. Despite showing a general stegosaurian appearance, the extensive phylogenetic analysis carried out depicts Isaberrysaura mollensis gen. et sp. nov. as a basal ornithopod, suggesting that both Thyreophora and neornithischians could have achieved significant convergent features. The specimen was preserved articulated and with some of its gut content place in the middle-posterior part of the thoracic cavity. Such stomach content was identified as seeds, most of them belonging to the Cycadales group. This finding reveals a possible and unexpected role of this ornithischian species as seed-dispersal agent.Facultad de Ciencias Naturales y Muse
    corecore