Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 148 )

2018 ( 893 )

2017 ( 932 )

2016 ( 1217 )

Custom range...

Search Results: 1 - 10 of 486612 matches for " Alberto K. De la Herrán-Arita "
All listed articles are free for downloading (OA Articles)
Page 1 /486612
Display every page Item
Narcolepsy and Orexins: An Example of Progress in Sleep Research
Alberto K. De la Herrán-Arita,René Drucker-Colín
Frontiers in Neurology , 2011, DOI: 10.3389/fneur.2011.00026
Abstract: Narcolepsy is a chronic neurodegenerative disease caused by a deficiency of orexin-producing neurons in the lateral hypothalamus. It is clinically characterized by excessive daytime sleepiness and by intrusions into wakefulness of physiological aspects of rapid eye movement sleep such as cataplexy, sleep paralysis, and hypnagogic hallucinations. The major pathophysiology of narcolepsy has been recently described on the bases of the discovery of the neuropeptides named orexins (hypocretins) in 1998; considerable evidence, summarized below, demonstrates that narcolepsy is the result of alterations in the genes involved in the pathology of the orexin ligand or its receptor. Deficient orexin transmission is sufficient to produce narcolepsy, as we describe here, animal models with dysregulated orexin signaling exhibit a narcolepsy-like phenotype. Remarkably, these narcoleptic models have different alterations of the orexinergic circuit, this diversity provide us with the means for making comparison, and have a better understanding of orexin-cell physiology. It is of particular interest that the most remarkable findings regarding this sleep disorder were fortuitous and due to keen observations. Sleep is a highly intricate and regulated state, and narcolepsy is a disorder that still remains as one of the unsolved mysteries in science. Nevertheless, advances and development of technology in neuroscience will provide us with the necessary tools to unravel the narcolepsy puzzle in the near future. Through an evaluation of the scientific literature we traced an updated picture of narcolepsy and orexins in order to provide insight into the means by which neurobiological knowledge is constructed.
Narcolepsy as an Immune-Mediated Disease
Alberto K. De la Herrán-Arita,Fabio García-García
Sleep Disorders , 2014, DOI: 10.1155/2014/792687
Abstract: Narcolepsy is a neurological disorder characterized by excessive daytime sleepiness, cataplexy, hypnagonic hallucinations, sleep paralysis, and disturbed nocturnal sleep patterns. This disease is secondary to the specific loss of hypothalamic hypocretin (orexin)-producing neurons in the lateral hypothalamus. An autoimmune basis for the disease has long been suspected based on its strong association with the genetic marker DQB1*06:02, and current studies greatly support this hypothesis. Narcolepsy with hypocretin deficiency is associated with human leukocyte antigen (HLA) and T cell receptor (TCR) polymorphisms, suggesting that an autoimmune process targets a peptide unique to hypocretin-producing neurons via specific HLA-peptide-TCR interactions. This concept has gained a lot of notoriety after the increase of childhood narcolepsy in 2010 following the 2009 H1N1 pandemic (pH1N1) in China and vaccination with Pandemrix, an adjuvanted H1N1 vaccine that was used in Scandinavia. The surge of narcolepsy cases subsequent to influenza A H1N1 infection and H1N1 vaccination suggests that processes such as molecular mimicry or bystander activation might be crucial for disease development. 1. Introduction Narcolepsy with hypocretin deficiency is a common sleep disorder that affects approximately 0.02% of the population worldwide and causes disability in 24% of the affected subjects. It is clinically characterized by excessive daytime sleepiness and abnormal sleep-wake patterns. These patients also suffer from cataplexy, a sudden loss of muscle tone triggered by strong emotions such as laughter, and are considered to be fragments of Rapid Eye Movement (REM) sleep that intrude into wakefulness, such as hypnagogic (dream-like) hallucinations as they drift off to sleep, as well as cataplexy (sudden loss of muscle tone triggered by strong emotions). All narcoleptic subjects present chronic sleepiness, but the intensity varies across the day and between individuals. This sleepiness is most troublesome during periods of inactivity, though it is often improved temporarily by a brief nap. As a consequence of sleepiness, patients may report inattention, poor memory, blurry vision, diplopia, and automatic behaviors such as driving without awareness [1–3]. 2. The Hypocretin System The disorder is caused by the specific loss of hypothalamic neurons producing two hypocretin peptides with high homology with each other, namely, hypocretin-1 and hypocretin-2 (also called orexin A and B), which are comprised of 33 and 28 amino acids, respectively [4–6]. These are produced by
Orexin receptor antagonists as therapeutic agents for insomnia
Ana C. Equihua,Alberto K. De La Herrán-Arita,Rene Drucker-Colin
Frontiers in Pharmacology , 2013, DOI: 10.3389/fphar.2013.00163
Abstract: Insomnia is a common clinical condition characterized by difficulty initiating or maintaining sleep, or non-restorative sleep with impairment of daytime functioning. Currently, treatment for insomnia involves a combination of cognitive behavioral therapy (CBTi) and pharmacological therapy. Among pharmacological interventions, the most evidence exists for benzodiazepine (BZD) receptor agonist drugs (GABAA receptor), although concerns persist regarding their safety and their limited efficacy. The use of these hypnotic medications must be carefully monitored for adverse effects. Orexin (hypocretin) neuropeptides have been shown to regulate transitions between wakefulness and sleep by promoting cholinergic/monoaminergic neural pathways. This has led to the development of a new class of pharmacological agents that antagonize the physiological effects of orexin. The development of these agents may lead to novel therapies for insomnia without the side effect profile of hypnotics (e.g., impaired cognition, disturbed arousal, and motor balance difficulties). However, antagonizing a system that regulates the sleep-wake cycle may create an entirely different side effect profile. In this review, we discuss the role of orexin and its receptors on the sleep-wake cycle and that of orexin antagonists in the treatment of insomnia.
An integrated multi period planning of the production and transportation of multiple petroleum products in a single pipeline system
Alberto Herrán,Fantahun M. Defersha,Mingyuan Chen,Jesús M. de la Cruz
International Journal of Industrial Engineering Computations , 2011,
Abstract: A multiproduct pipeline provides an economic way to transport large volumes of refined petroleum products over long distances. In such a pipeline, different products are pumped back to back without any separation device between them. The sequence and lengths of such pumping runs must be carefully selected in order to meet market demands while minimizing pipeline operational costs and satisfying several constraints. The production planning and scheduling of the products at the refinery must also be synchronized with the transportation in order to avoid the usage of the system at some peak hour time intervals. In this paper, we propose a multi period mixed integer nonlinear programming (MINLP) model for an optimal planning and scheduling of the production and transportation of multiple petroleum products from a refinery plant connected to several depots through a single pipeline system. The objective of this work is to generalize the mixed integer linear programming (MILP) formulation proposed by Cafaro and Cerdá (2004, Computers and Chemical Engineering) where only a single planning period was considered and the production planning and scheduling was not part of the decision process. Numerical examples show how the use of a single period model for a given time period may lead to infeasible solutions when it is used for the upcoming periods. These examples also show how integrating production planning with the transportation and the use of a multi period model may result in a cost saving compared to using a single period model for each period, independently.
Comparison of T1 conditions for multiparameter operators
Ana Grau de la Herrán
Mathematics , 2014,
Abstract: We prove that for $L^2$ bounded operators T, the classes of operators defined in the language of vector-valued Calder\'on-Zygmund theory by Journ\'e in his proof of the T1 theorem on product spaces is of the same class as the later biparameter operators defined as the Pott and Villarroya type in their proof of the T1 theorem on product spaces.
Un Sistema para la Evaluación de Lastres para la Creatividad
de la Herrán Gascón Agustín
Indivisa : Boletin de Estudios e Investigación , 2005,
Introducción a la madurez organizacional
de la Herrán Gascón Agustín
Indivisa : Boletin de Estudios e Investigación , 2006,
El docente de baja autoestima: Implicaciones didácticas
de la Herrán Gascón Agustín
Indivisa : Boletin de Estudios e Investigación , 2004,
Estados de conciencias y educación: implicaciones para la didáctica general y la formación del profesorado
Herrán Gascón Agustín de la
Indivisa : Boletin de Estudios e Investigación , 2007,
Introducción a una Pedagogía de la muerte
Herrán Gascón Agustín de la,Cortina Selva Mar
Indivisa : Boletin de Estudios e Investigación , 2007,
Page 1 /486612
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.