Search results for "CORT"
showing 10 items of 3558 documents
Lymphocyte beta-adrenergic receptors in young subjects with peripheral or central obesity: relationship with central haemodynamics and left ventricul…
1994
This study was designed to evaluate total (t) and surface (s) β-adrenergic receptor (BAR) density and their relationship with central haemodynamics and left ventricular function in young subjects with central or peripheral obesity. A total of 31 obese subjects (BMI ≥30.5 kg. m−2 for males and >27.3 kg. m−2 for females) aged less than 40 years and without other risk factors for cardiovascular diseases (smoking, hypertension, diabetes and lipid abnormalities) were studied. Nine had peripheral obesity and 22 central obesity according to WHR values; there were 20 lean controls (BMI <25 kg. m−2 for males and <24.7 kg. m−2 for females). Casual (c) and 24 h ambulatory mean blood pressures (MBP-24 …
Circadian variations in antigen-specific proliferation of human T lymphocytes and correlation to cortisol production.
1995
Cortisol is a well-known immunosuppressant when used therapeutically. The present investigation was set out to study if diurnal variations in endogenous cortisol production are reflected by changes in proliferative responses of human lymphocytes to either a mitogen (phytohemagglutinin-A, PHA) or an antigen (tetanus toxoid, TT) stimulus. The study included eight healthy volunteers. Blood was withdrawn at 0200, 0600, 1000, and 1800h for preparation of lymphocytes and determination of cortisol in plasma. Isolated cells were incubated without (baseline activity) or with inclusion of either 1 micrograms PHA or 10 micrograms TT. Proliferation was measured by labelling with 3H-thymidine for 16 h o…
Hypo-excitability of cortical areas in patients affected by Friedreich ataxia: A TMS study
2005
The aim of the study was to explore excitability of a motor and a non-motor (visual) area in patients affected by Friedreich ataxia and to correlate neurophysiological data with clinical parameters. Seven patients (3M/4F) and ten healthy controls (5M/5F) participated in the study. The hot-spot for activation of right abductor pollicis brevis was checked by means of a figure-of-eight coil and the motor threshold (MT) on this point was recorded. The phosphene threshold (PT) was measured by means of a focal coil over the occipital cortex as the lower intensity of magnetic stimulation able to induce the perception of phosphenes. The patients showed a significantly higher mean PT (p<.03) and MT …
Effects of cerebellar TMS on motor cortex of patient with focal dystonia: a preliminary report
2008
Recent evidence suggests a role for cerebellum in pathophysiology of dystonia. Here we explored, the cerebellar modulation of motor cortex in patients with focal upper limb dystonia. Eight patients and eight controls underwent a transcranial magnetic stimulation protocol to study the cerebellar-brain-inhibition (CBI): a conditioning cerebellar stimulus (CCS) was followed 5 ms after by the contralateral motor cortex stimulation (test stimulus: TS). We explored the effects of CBI on MEP amplitude, short intracortical inhibition (SICI) and intracortical facilitation (ICF) measures. At baseline no differences in TS-MEP amplitude, SICI or ICF were found between patients and controls. Cerebellar-…
Representation of time intervals in the right posterior parietal cortex: implications for a mental time line
2009
Space and time interact with each other in the cognitive system. Recent studies indicate the posterior parietal cortex (PPC) as the neural correlate of spatial-temporal interactions. We studied whether the contribution of the PPC becomes critical in tasks requiring the performance of spatial computations on time intervals. We adopted an integrated neuropsychological and transcranial magnetic stimulation (rTMS) approach, presenting behavioural timing tasks to both healthy subjects and right-brain-damaged patients with and without evidence of spatial neglect. rTMS of the right PPC of healthy subjects induced a lateralised bias during a task requiring setting the midpoint of a time interval. T…
Neural discrimination of nonprototypical chords in music experts and laymen:an MEG study
2009
Abstract At the level of the auditory cortex, musicians discriminate pitch changes more accurately than nonmusicians. However, it is not agreed upon how sound familiarity and musical expertise interact in the formation of pitch-change discrimination skills, that is, whether musicians possess musical pitch discrimination abilities that are generally more accurate than in nonmusicians or, alternatively, whether they may be distinguished from nonmusicians particularly with respect to the discrimination of nonprototypical sounds that do not play a reference role in Western tonal music. To resolve this, we used magnetoencephalography (MEG) to measure the change-related magnetic mismatch response…
Functional MRI of galvanic vestibular stimulation with alternating currents at different frequencies.
2004
Abstract Functional MRI was performed in 28 healthy volunteers to study the effects of galvanic vestibular stimulation with alternating currents (AC-GVS) of different frequencies on brain activation patterns. The aims of this study were (1) to identify specific areas within the vestibular cortical network that are involved in the processing of frequency-specific aspects by correlation analyses, (2) to determine the optimal frequency for stimulation of the vestibular system with respect to perception, and (3) to analyze whether different frequencies of AC-GVS are mediated in different cortical areas or different sites within the vestibular cortex. AC-GVS was performed using sinusoidal stimul…
The thalamus as the generator and modulator of EEG alpha rhythm: a combined PET/EEG study with lorazepam challenge in humans
2003
Background: Purpose of this study was to investigate the functional relationship between electroencephalographic (EEG) alpha power and cerebral glucose metabolism before and after pharmacological alpha suppression by lorazepam. Methods: Ten healthy male volunteers were examined undergoing two F18-fluorodeoxyglucose (18-FDG) positron emission tomography (PET) scans with simultaneous EEG recording: 1× placebo, 1× lorazepam. EEG power spectra were computed by means of Fourier analysis. The PET data were analyzed using SPM99, and the correlations between metabolism and alpha power were calculated for both conditions. Results: The comparison lorazepam versus placebo revealed reduced glucose meta…
Cortical representation of saccular vestibular stimulation: VEMPs in fMRI
2006
Short tone bursts trigger a vestibular evoked myogenic potential (VEMP), an inhibitory potential which reflects a component of the vestibulocollic reflex (VCR). These potentials arise as a result of activation of the sacculus and are expressed through the vestibulo-collic reflex (VCR). Up to now, the ascending projections of the sacculus are unknown in humans, only the representation of the semicircular canals or the entire vestibular nerve has been demonstrated. The aim of this study was to determine whether a sacculus stimulus that evoked VEMPs could activate vestibular cortical areas in fMRI. To determine this, we studied the differential effects of unilateral VEMP stimulation in 21 heal…
Modulating phonemic fluency performance in healthy subjects with transcranial magnetic stimulation over the left or right lateral frontal cortex.
2017
Abstract A growing body of evidence have suggested that non-invasive brain stimulation techniques, such as transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), can improve the performance of aphasic patients in language tasks. For example, application of inhibitory rTMS or tDCs over the right frontal lobe of dysphasic patients resulted in improved naming abilities. Several studies have also reported that in healthy controls (HC) tDCS application over the left prefrontal cortex (PFC) improve performance in naming and semantic fluency tasks. The aim of this study was to investigate in HC, for the first time, the effects of inhibitory repetitive TMS (rTMS…