981 resultados para Startle-reflex


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We compared the pupil responses originating from outer versus inner retinal photoreception between patients with isolated hereditary optic neuropathy (HON, n = 8) and healthy controls (n = 8). Three different testing protocols were used. For the first two protocols, a response function of the maximal pupil contraction versus stimulus light intensity was generated and the intensity at which half of the maximal pupil contraction, the half-max intensity, was determined. For the third protocol, the pupil size after light offset, the re-dilation rate and re-dilation amplitude were calculated to assess the post-light stimulus response. Patients with HON had bilateral, symmetric optic atrophy and significant reduction of visual acuity and visual field compared to controls. There were no significant mean differences in the response curve and pupil response parameters that reflect mainly rod, cone or melanopsin activity between patients and controls. In patients, there was a significant correlation between the half-max intensity of the red light sequence and visual field loss. In conclusion, pupil responses derived from outer or inner retinal photoreception in HON patients having mild-to moderate visual dysfunction are not quantitatively different from age-matched controls. However, an association between the degree of visual field loss and the half-max intensity of the cone response suggests that more advanced stages of disease may lead to impaired pupil light reflexes.

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La migradesa d'estudis sobre la formació i les característiques del mapa municipal catala ha permes difondre la idea de que la seva actual configuració ha romas invariable des de sempre, i que és fruit d'uns fets dits naturals. Aquests suposits tenen una clara conseqüencia practica: qualsevol alteració de la fesomia municipal catalana és un atac a les essencies del país. L'objectiu últim d'aquest treball és justament el de presentar la realitat municipal com un fenomen molt més dinamic que no pas sembla, sotmes, com tot fet huma, aljoc d'interessos dels diversos grups socials i reflex d'un determinat model d'ordenació territorial. Creiem que aquesta perspectiva histórica permetra entendre millor la genesi d'un mapa municipal que cada cop apareix més inadaptat als veritables ambits de relació quotidiana i, per aquesta raó, incapac d'afrontar els reptes d'una administració local eficac i participativa.

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A Catalunya, entre els segles XIII i XV, s'articula Palta delegado del sobirá, veritable reflex de la consolidado de la posició reial i catalitzadora de les tensions entre els vectors de poder. La figura es mostra com elevada magistratura d'un país cohesionat per la propia sinergia deis diferents grups de pressió, entre els quals evolucionará fins a sortir dels temps medievals amb una posició afermada pero, alhora, ja desplagada de destacades preeminéncies. El recorregut per aquesta institució, dones, transporta la consolidació reial entre l'emergéncia municipal i la puixanga baronial a través de les llums i foscors deis segles que clouen l'edat mitjana.

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El futbol constitueix al nostre país, igual com en d’altres Estats del nostre entorn, un fenomen que transcendeix allò merament esportiu per esdevenir un referent social que desperta passions i que té el seu consegüent reflex als mitjans de comunicació social. No és, doncs, estrany, que de forma diària la premsa esportiva d’àmbit nacional proporcioni informació constant sobre la matèria, incloent-hi allò que concerneix a les lesions que afecten els jugadors, car consideren que és un fet noticiable en la mesura en què això pugui influir en les expectatives dels diferents equips. La informació esmentada, adequadament recollida, sistematitzada i analitzada és susceptible de proporcionar valuoses dades sobre la incidència de les lesions en aquesta modalitat esportiva. Aquest és, precisament, l’objectiu del nostre estudi, sense una altra pretensió que la de proporcionar unes pautes a prendre en consideració per part dels professionals, perquè el seu esforç se centri en l’optimització del rendiment, la planificació de la temporada, l’establiment de programes de prevenció i, al capdavall, en la minimització del risc de lesions.

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El fútbol constituye en nuestro país, al igual que en otros Estados de nuestro entorno, un fenómeno que trasciende de lo meramente deportivo para convertirse en un referente social que despierta pasiones y que tiene su consiguiente reflejo en los medios de comunicación social. No es pues de extrañar que de forma diaria la prensa deportiva de ámbito nacional proporcione información constante sobre la materia, incluyendo lo concerniente a las lesiones que aquejan a los jugadores considerándolo hecho noticiable en la medida que ello pueda afectar a las expectativas de los diferentes equipos. Dicha información, debidamente recogida, sistematizada y analizada, es susceptible de proporcionar valiosos datos sobre la incidencia lesional en esta modalidad deportiva. Éste es precisamente el objetivo de nuestro estudio, sin otra pretensión que la de proporcionar unas pautas a tomar en consideración por los profesionales cuyo esfuerzo se centre en la optimización del rendimiento, en la planificación de la temporada, en el establecimiento de programas de prevención y, en definitiva, en la minimización del riesgo lesional.

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Introduction: The coexistence of different molecular types of classical protease-resistant prion protein in the same individual have been described, however, the simultaneous finding of these with the recently described protease-sensitive variant or variably protease-sensitive prionopathy has, to the best of our knowledge, not yet been reported. Case presentation: A 74-year-old Caucasian woman showed a sporadic Creutzfeldt-Jakob disease clinical phenotype with reactive depression, followed by cognitive impairment, akinetic-rigid Parkinsonism with pseudobulbar syndrome and gait impairment with motor apraxia, visuospatial disorientation, and evident frontal dysfunction features such as grasping, palmomental reflex and brisk perioral reflexes. She died at age 77. Neuropathological findings showed: spongiform change in the patient"s cerebral cortex, striatum, thalamus and molecular layer of the cerebellum with proteinase K-sensitive synaptic-like, dot-like or target-like prion protein deposition in the cortex, thalamus and striatum; proteinase K-resistant prion protein in the same regions; and elongated plaque-like proteinase K-resistant prion protein in the molecular layer of the cerebellum. Molecular analysis of prion protein after proteinase K digestion revealed decreased signal intensity in immunoblot, a ladder-like protein pattern, and a 71% reduction of PrPSc signal relative to non-digested material. Her cerebellum showed a 2A prion protein type largely resistant to proteinase K. Genotype of polymorphism at codon 129 was valine homozygous. Conclusion: Molecular typing of prion protein along with clinical and neuropathological data revealed, to the best of our knowledge, the first case of the coexistence of different protease-sensitive prion proteins in the same patient in a rare case that did not fulfill the current clinical diagnostic criteria for either probable or possible sporadic Creutzfeldt-Jakob disease. This highlights the importance of molecular analyses of several brain regions in order to correctly diagnose rare and atypical prionopathies

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OBJECTIVE: In contrast to conventional (CONV) neuromuscular electrical stimulation (NMES), the use of "wide-pulse, high-frequencies" (WPHF) can generate higher forces than expected by the direct activation of motor axons alone. We aimed at investigating the occurrence, magnitude, variability and underlying neuromuscular mechanisms of these "Extra Forces" (EF). METHODS: Electrically-evoked isometric plantar flexion force was recorded in 42 healthy subjects. Additionally, twitch potentiation, H-reflex and M-wave responses were assessed in 13 participants. CONV (25Hz, 0.05ms) and WPHF (100Hz, 1ms) NMES consisted of five stimulation trains (20s on-90s off). RESULTS: K-means clustering analysis disclosed a responder rate of almost 60%. Within this group of responders, force significantly increased from 4% to 16% of the maximal voluntary contraction force and H-reflexes were depressed after WPHF NMES. In contrast, non-responders showed neither EF nor H-reflex depression. Twitch potentiation and resting EMG data were similar between groups. Interestingly, a large inter- and intrasubject variability of EF was observed. CONCLUSION: The responder percentage was overestimated in previous studies. SIGNIFICANCE: This study proposes a novel methodological framework for unraveling the neurophysiological mechanisms involved in EF and provides further evidence for a central contribution to EF in responders.

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This paper investigates the determinants of job satisfaction of university graduates in Spain. We base our analysis on Locke"s discrepancy theory [Locke (1969)] and decompose subjective evaluation of job characteristics into surplus and deficit levels. We also study the importance of overeducation and over-skilling on job satisfaction. We use REFLEX data, a survey of university graduates. We conclude that job satisfaction is mostly determined by the subjective evaluation of intrinsic job characteristics, with an asymmetric impact of surpluses and deficits. Over-skilling is much more important than over-education in explaining the job satisfaction of university graduates, although the latter is also significant.

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BACKGROUND: After no research in humans for >40 years, there is renewed interest in using lysergic acid diethylamide (LSD) in clinical psychiatric research and practice. There are no modern studies on the subjective and autonomic effects of LSD, and its endocrine effects are unknown. In animals, LSD disrupts prepulse inhibition (PPI) of the acoustic startle response, and patients with schizophrenia exhibit similar impairments in PPI. However, no data are available on the effects of LSD on PPI in humans. METHODS: In a double-blind, randomized, placebo-controlled, crossover study, LSD (200 μg) and placebo were administered to 16 healthy subjects (8 women, 8 men). Outcome measures included psychometric scales; investigator ratings; PPI of the acoustic startle response; and autonomic, endocrine, and adverse effects. RESULTS: Administration of LSD to healthy subjects produced pronounced alterations in waking consciousness that lasted 12 hours. The predominant effects induced by LSD included visual hallucinations, audiovisual synesthesia, and positively experienced derealization and depersonalization phenomena. Subjective well-being, happiness, closeness to others, openness, and trust were increased by LSD. Compared with placebo, LSD decreased PPI. LSD significantly increased blood pressure, heart rate, body temperature, pupil size, plasma cortisol, prolactin, oxytocin, and epinephrine. Adverse effects produced by LSD completely subsided within 72 hours. No severe acute adverse effects were observed. CONCLUSIONS: In addition to marked hallucinogenic effects, LSD exerts methylenedioxymethamphetamine-like empathogenic mood effects that may be useful in psychotherapy. LSD altered sensorimotor gating in a human model of psychosis, supporting the use of LSD in translational psychiatric research. In a controlled clinical setting, LSD can be used safely, but it produces significant sympathomimetic stimulation.

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Neuronal circuit asymmetries are important components of brain circuits, but the molecular pathways leading to their establishment remain unknown. Here we found that the mutation of FRMD7, a gene that is defective in human congenital nystagmus, leads to the selective loss of the horizontal optokinetic reflex in mice, as it does in humans. This is accompanied by the selective loss of horizontal direction selectivity in retinal ganglion cells and the transition from asymmetric to symmetric inhibitory input to horizontal direction-selective ganglion cells. In wild-type retinas, we found FRMD7 specifically expressed in starburst amacrine cells, the interneuron type that provides asymmetric inhibition to direction-selective retinal ganglion cells. This work identifies FRMD7 as a key regulator in establishing a neuronal circuit asymmetry, and it suggests the involvement of a specific inhibitory neuron type in the pathophysiology of a neurological disease. VIDEO ABSTRACT.

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A comparative study of the two published Catalan translations of Charles Dickens’ David Copperfield, the first translated by Josep Carner in 1930 but not published until 1964, and the second by Joan Sellent in 2003. The analysis shows that both translations, magnificent, reflect the unique evolution of the language model that the translators pass on to their readers, an evolution shaped by the complex history of the Catalan language in the 20th century, which is still to be written

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The aim of this study was to prospectively assess the prevalence of orthoptic anomalies following conservative management of pure blowout orbital fractures and to evaluate their clinical relevance. Clinical and radiologic data of patients with unilateral conservatively managed pure blowout orbital fractures with a minimum follow-up of 6 months were reviewed. Eligible patients were contacted and invited to undergo an extended ophthalmologic examination as follows: distance and near visual acuities, Hertel exophthalmometry, corneal light reflex (Hirschberg test), ductions and versions in the 6 cardinal fields of gaze, eye deviation with prisms and alternate cover test in all of the 9-gaze directions with Maddox rod, degrees of incyclo/excyclotorsion with right and left eye fixation, horizontal and vertical deviation with Hess-Weiss coordimetry, degree of horizontal/vertical and incyclo/excyclotorsion deviation with Harms wall deviometry, and vertical deviation with Bielschowsky head-tilt test. Of the 69 patients contacted, 49 declined to participate given that they were asymptomatic. Twenty patients agreed to undergo the examination. One patient complained of minimal double vision limited to the extreme downgaze. Four patients had asymptomatic ocular motility disturbances limited to the extreme gaze. Seven patients had asymptomatic horizontal heterophoria. These disturbances did not interfere with daily or professional activities in any of the patients. The current study demonstrated that conservative management of pure orbital blowout fractures can result in orthoptic anomalies. These sequelae were restricted to a very limited portion of the binocular field of the vision and were not found to be clinically relevant.

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PURPOSE: This study aims to identify which aspects of the pupil light reflex are most influenced by rods and cones independently by analyzing pupil recordings from different mouse models of photoreceptor deficiency. METHODS: One-month-old wild type (WT), rodless (Rho-/-), coneless (Cnga3-/-), or photoreceptor less (Cnga3-/-; Rho-/- or Gnat1-/-) mice were subjected to brief red and blue light stimuli of increasing intensity. To describe the initial dynamic response to light, the maximal pupillary constriction amplitudes and the derivative curve of the first 3 seconds were determined. To estimate the postillumination phase, the constriction amplitude at 9.5 seconds after light termination was related to the maximal constriction amplitude. RESULTS: Rho-/- mice showed decreased constriction amplitude but more prolonged pupilloconstriction to all blue and red light stimuli compared to wild type mice. Cnga3-/- mice had constriction amplitudes similar to WT however following maximal constriction, the early and rapid dilation to low intensity blue light was decreased. To high intensity blue light, the Cnga3-/- mice demonstrated marked prolongation of the pupillary constriction. Cnga3-/-; Rho-/- mice had no pupil response to red light of low and medium intensity. CONCLUSIONS: From specific gene defective mouse models which selectively voided the rod or cone function, we determined that mouse rod photoreceptors are highly contributing to the pupil response to blue light stimuli but also to low and medium red stimuli. We also observed that cone cells mainly drive the partial rapid dilation of the initial response to low blue light stimuli. Thus photoreceptor dysfunction can be derived from chromatic pupillometry in mouse models.

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L’escola és un reflex de la societat en la que s’inscriu. Una societat democràtica comporta una escola que visqui i practiqui la democràcia. Els nostres drets, les nostres llibertats i els nostres deures descansen sobre la nostra autonomia i responsabilitat. Una manera de treballar aquests aspectes a l’escola és des del projecte de convivència de centre, on s’ha d’incardinar tota la vida del centre educatiu. Educar en valors exigeix conviure amb ells en tots els àmbits de la nostra vida. Educar en valors significa, també, educar la capacitat de valorar. Aquesta capacitat de valorar ens permet ser persones lliures, crítiques, justes i solidàries, conscients de la realitat del nostre entorn més immediat i del context mundial en general, i compromeses amb la humanitat, amb les generacions futures i amb la sostenibilitat del planeta. D’acord amb aquestes consideracions, el projecte de convivència de centre pot fonamentar-se en els següents tres grans blocs de valors, en els quals hi podem encabir els valors, entesos com les nostres opcions de vida: a) el valor de la persona humana i la seva dignitat; b) el valor de la democràcia i la ciutadania; i c) el valor de la igualtat i la diferència.

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El gener de 2012 va entrar en vigor a Catalunya la prohibició dels espectacles taurins que provoquen la mort de l'animal, la qual pot esdevenir inútil si el govern espanyol els declara patrimoni cultural immaterial. Se n'ha parlat en diversos mitjans, amb arguments tant favorables com contraris, els quals en general debaten si és una demostració artística o de crueltat, i si la prohibició catalana i la declaració que impulsa el govern espanyol són el reflex d'una qüestió política o un acte d'humanitat per evitar un patiment inútil. També hi ha, però, un altre aspecte a tenir en compte, l'impacte cognitiu que pot tenir en els assistents i com pot repercutir en la societat. No hi ha gaires dades científiques sobre un tema tan concret com aquest, perquè, d'una banda, en altres països el problema és inexistent, i d'una altra, dubto que cap ministeri espanyol financés una recerca per abordar-lo.