Supraorbital transcutaneous neurostimulation has sedative effects in healthy subjects

Transcutaneous neurostimulation (TNS) at extracephalic sites is a well known treatment of pain. Thanks to recent technical progress, the Cefaly® device now also allows supraorbital TNS. During observational clinical studies, several patients reported decreased vigilance or even sleepiness during a session of supraorbital TNS. We decided therefore to explore in more detail the potential sedative effect of supraorbital TNS, using standardized psychophysical tests in healthy volunteers.Clinical TrialJournal Articleinfo:eu-repo/semantics/publishe

Altered processing of sensory stimuli in patients with migraine

Migraine is a cyclic disorder, in which functional and morphological brain changes fluctuate over time, culminating periodically in an attack. In the migrainous brain, temporal processing of external stimuli and sequential recruitment of neuronal networks are often dysfunctional. These changes reflect complex CNS dysfunction patterns. Assessment of multimodal evoked potentials and nociceptive reflex responses can reveal altered patterns of the brain's electrophysiological activity, thereby aiding our understanding of the pathophysiology of migraine. In this Review, we summarize the most important findings on temporal processing of evoked and reflex responses in migraine. Considering these data, we propose that thalamocortical dysrhythmia may be responsible for the altered synchronicity in migraine. To test this hypothesis in future research, electrophysiological recordings should be combined with neuroimaging studies so that the temporal patterns of sensory processing in patients with migraine can be correlated with the accompanying anatomical and functional changes

Mesenchymal Stem Cell Graft Improves Recovery after Spinal Cord Injury in Adult Rats through Neurotrophic and Pro-Angiogenic Actions

Numerous strategies have been managed to improve functional recovery after spinal cord injury (SCI) but an optimal strategy doesn't exist yet. Actually, it is the complexity of the injured spinal cord pathophysiology that begets the multifactorial approaches assessed to favour tissue protection, axonal regrowth and functional recovery. In this context, it appears that mesenchymal stem cells (MSCs) could take an interesting part. The aim of this study is to graft MSCs after a spinal cord compression injury in adult rat to assess their effect on functional recovery and to highlight their mechanisms of action. We found that in intravenously grafted animals, MSCs induce, as early as 1 week after the graft, an improvement of their open field and grid navigation scores compared to control animals. At the histological analysis of their dissected spinal cord, no MSCs were found within the host despite their BrdU labelling performed before the graft, whatever the delay observed: 7, 14 or 21 days. However, a cytokine array performed on spinal cord extracts 3 days after MSC graft reveals a significant increase of NGF expression in the injured tissue. Also, a significant tissue sparing effect of MSC graft was observed. Finally, we also show that MSCs promote vascularisation, as the density of blood vessels within the lesioned area was higher in grafted rats. In conclusion, we bring here some new evidences that MSCs most likely act throughout their secretions and not via their own integration/differentiation within the host tissue

Sodium Valproate in Severe Migraine and Tension-Type Headache: An Open Study of Long-Term Efficacy and Correlation with Blood Levels

We performed an open prospective study of the prophylactic efficacy of sodium valproate in 56 patients among which 35 migraineurs, 7 chronic tension-type headache patients and 14 patients with combined headaches. We compared the mean number of headache days per month during a one-month-baseline period without prophylactic treatment and during the last month of a 6-month-treatment course. Among secondary parameters, we assessed headache intensity, adverse experiences and we measured valproate blood levels after one and after six months of treatment. Sixty percent of migraineurs had a 75% or more improvement in the number of headache days under sodium valproate, most of the remaining attacks being less severe. There was no significant improvement in chronic tension-type headache patients and only a mild effect in patients with combined headaches, almost exclusively on the migraine component. Thirty percent of patients reported adverse effects of which none was serious: there were 3 drop-outs. We found a moderate, but statistically significant, correlation between efficacy and blood levels of sodium valproate

A neural network model of sensitization of evoked cortical responses in migraine

Migraine patients show abnormalities of cerebral electrophysiology that manifest themselves mainly during the attack interval. Cortical-evoked potentials of migraineurs fail to habituate to repetitive presentations of visual stimuli, and the amplitude of components of their auditory cortical-evoked potentials have a higher dependence on the stimulus intensities than in healthy subjects. A computer model of a neural hetwork has been developed that is able to reproduce both these neurophysiological dysfunctions. It predicts a positive correlation between the magnitudes of both these dysfunctions. The model also offers an explanation of why mutations in the same ion channel gene with opposite consequences on channel function, e.g. P/Q Ca2+ channels in migraine, may lead to similar electrophysiological abnormalities

A clinical comparison of sumatriptan nasal spray and dihydroergotamine nasal spray in the acute treatment of migraine.

A multinational, multicentre, randomised, double-blind, double-dummy, crossover study (368 patients treating two attacks) was conducted to compare the efficacy and tolerability of sumatriptan nasal spray (20 mg) with dihydroergotamine (DHE) nasal spray (1 mg plus optional 1 mg). At the primary efficacy time point of 60 minutes after dosing, significantly more patients obtained headache relief (change from moderate or severe to none or mild) after treatment with sumatriptan than with DHE (53% sumatriptan, 41% DHE, p < 0.001). Significantly more patients reported relief of nausea after sumatriptan than after DHE at 60 minutes (64% sumatriptan, 49% DHE, p = 0.006). A significant difference between the two treatments was first observed at 45 minutes with respect to both headache relief (38% sumatriptan, 31% DHE, p = 0.037) and relief of nausea (55% sumatriptan, 40% DHE, p = 0.014). There were no significant differences between the two treatments for other measures of efficacy. Both treatments were well tolerated, with only 10% of patients in each group reporting one or more adverse events. The most frequently reported adverse event after sumatriptan was a bad or bitter taste, which was reported by 5% of patients. After DHE, 4% of patients reported symptoms of the nasal cavity/sinuses and 3% reported nausea and/or vomiting as adverse events. It is concluded that sumatriptan nasal spray is superior to DHE nasal spray in the relief of pain and nausea associated with acute migraine headache