Search results for "Cortex"
showing 10 items of 1827 documents
Effects of caffeine on neuromuscular function in a non‐fatigued state and during fatiguing exercise
2020
New findings What is the central question of the study? What are the effects of caffeine on neuromuscular function in a non-fatigued state and during fatiguing exercise? What is the main finding and its importance? In a non-fatigued state, caffeine decreased the duration of the silent period evoked by transcranial magnetic stimulation. Caffeine-induced reduction of inhibitory mechanisms in the central nervous system before exercise was associated with an increased performance. Individuals who benefit from caffeine ingestion may experience lower perception of effort during exercise and an accelerated recovery of M-wave amplitude postfatigue. This study elucidates the mechanisms of action of …
Quantitative mass spectrometry for human melanocortin peptides in vitro and in vivo suggests prominent roles for β-MSH and desacetyl α-MSH in energy …
2018
Objective The lack of pro-opiomelanocortin (POMC)-derived melanocortin peptides results in hypoadrenalism and severe obesity in both humans and rodents that is treatable with synthetic melanocortins. However, there are significant differences in POMC processing between humans and rodents, and little is known about the relative physiological importance of POMC products in the human brain. The aim of this study was to determine which POMC-derived peptides are present in the human brain, to establish their relative concentrations, and to test if their production is dynamically regulated. Methods We analysed both fresh post-mortem human hypothalamic tissue and hypothalamic neurons derived from …
The reliability of continuous brain responses during naturalistic listening to music
2015
Low-level (timbral) and high-level (tonal and rhythmical) musical features during continuous listening to music, studied by functional magnetic resonance imaging (fMRI), have been shown to elicit large-scale responses in cognitive, motor, and limbic brain networks. Using a similar methodological approach and a similar group of participants, we aimed to study the replicability of previous findings. Participants' fMRI responses during continuous listening of a tango Nuevo piece were correlated voxelwise against the time series of a set of perceptually validated musical features computationally extracted from the music. The replicability of previous results and the present study was assessed b…
The chronnectome of musical beat
2020
Keeping time is fundamental for our everyday existence. Various isochronous activities, such as locomotion, require us to use internal timekeeping. This phenomenon comes into play also in other human pursuits such as dance and music. When listening to music, we spontaneously perceive and predict its beat. The process of beat perception comprises both beat inference and beat maintenance, their relative importance depending on the salience of beat in the music. To study functional connectivity associated with these processes in a naturalistic situation, we used functional magnetic resonance imaging to measure brain responses of participants while they were listening to a piece of music contai…
Resonance of cortico-cortical connections of the motor system with the observation of goal directed grasping movements
2010
Goal directed movements require the activation of parietal, premotor and primary motor areas. In monkeys, neurons of these areas become active also during the observation of movements performed by others, especially for coding the goal of the action (mirror system). Using bifocal transcranial magnetic stimulation (TMS) in healthy subjects, we tested whether the observation of goal directed reach to grasp actions may lead to specific changes in the short-latency connections linking key areas of the mirror system, such as the anterior intraparietal cortex (AIP) and the ventral premotor cortex (PMv), with the primary motor cortex (M1). We found that AIP-M1 and PMv-M1 cortico-cortical interacti…
Intrinsically determined cell death of developing cortical interneurons.
2009
The cell death of inhibitory neurons, which originate far from the cortical areas to which they migrate during embryonic development, is determined autonomously rather than by competition for trophic signals from other cell types. It has long been known that apoptosis, a form of programmed cell death, eliminates young cells from developing tissues. In the field of neurobiology, it is widely believed that developmental neuronal-cell death results from cellular competition for environmentally derived survival signals that selects for an optimally sized and properly wired population of neurons. This study of developmental cell death in the mouse cortex in vivo, in vitro and after transplantati…
Omalizumab reduces oral corticosteroid use in patients with severe allergic asthma: Real-life data
2010
SummaryBackgroundLong-term oral corticosteroid (OCS) therapy is associated with significant burden on patients and healthcare resources; treatments that may help reduce their use are important to improve asthma management.MethodsFrench and German clinicians prescribing omalizumab for >16 weeks to patients with severe persistent allergic asthma collected OCS use data. OCS use was recorded at baseline and at a non-specific time point beyond 16 weeks from initiation of omalizumab. The number of asthma exacerbations (FEV1 16 weeks. Of these, 166 (48.0%) were receiving maintenance OCS (France, n = 64; Germany, n = 102). Following omalizumab therapy, 84 (50.6%) patients on OCS at baseline reduced…
Blood eosinophils and treatment response in hospitalized exacerbations of chronic obstructive pulmonary disease: A case-control study
2015
Background: In outpatients with chronic obstructive pulmonary disease (COPD), blood eosinophilia is considered as a biomarker of response to systemic corticosteroid therapy. However, little is known on whether blood eosinophilia is also predictive of positive clinical outcome in severe acute exacerbations of COPD requiring hospitalization. We hypothesized that blood eosinophil-positive severe acute exacerbations of COPD differ from eosinophil-negative ones in terms of response to therapy and clinical outcomes. Methods: To test our experimental hypothesis, we retrospectively analyzed medical records of patients with COPD admitted to our ward because of severe exacerbation, over a two-year pe…
GOLD 2017 treatment pathways in ‘real life’: An analysis of the DACCORD observational study
2017
Abstract Introduction The 2017 update to the Global Initiative for Obstructive Lung Disease (GOLD) strategy document includes recommendations for treatment intensification or step-down in chronic obstructive pulmonary disease (COPD), although recognises that limited supporting information is available. DACCORD is an ongoing observational, non-interventional study, recruiting patients following COPD maintenance treatment change or initiation, a subset of whom were receiving a long-acting β2-agonist (LABA) plus a long-acting muscarinic antagonist (LAMA) fixed-dose combination (FDC) on entry. Since there were no requirements in terms of prior medication (and no washout before commencing LABA/L…
Modulation of spinal excitability by a sub-threshold stimulation of M1 area during muscle lengthening
2013
Abstract It is well known that the H-reflex amplitude decreases during passive muscle lengthening in comparison with passive shortening. However, this decrease in spinal synaptic efficacy observed during passive lengthening seems to be lesser during eccentric voluntary contraction. The aim of the present study was to examine whether spinal excitability during lengthening condition could be modulated by magnetic brain stimulation. H reflexes of the triceps surae muscles were elicited on 10 young healthy subjects, and conditioned by a sub-threshold transcranial magnetic stimulation (TMS). The conditioning stimulation was applied over the M1 area of triceps surae muscles at an intensity below …