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Objective : The aim of the present study was to analyze in detail the relationship of two newly introduced measures, related to the Beta and Gamma EEG bands during REM sleep, with Delta and Sigma activity at REM sleep onset and REM sleep end, in order to understand their eventual role in the sleep modulation mechanism. Methods : For this purpose, power spectra of 1 EEG channel (C4, referred to A1) were obtained by means of the fast Fourier transform and the power of the bands ranging 0.75–4.50 Hz (Delta), 4.75–7.75 (Theta), 8.00–12.25 (Alpha), 12.50–15.00 (Sigma), 15.25–24.75 (Beta), 25.00–34.75 (Gamma 1), and 35.00–44.75 (Gamma 2) was calculated for the whole period of analysis (7 h), in 10 healthy subjects. Additionally, two other time series were calculated: the ratio between Beta and Gamma2, and between Gamma1 and Gamma2 (Beta and Gamma ratios). For each subject, we extracted 3 epochs of 30 min corresponding to the 15 min preceding and the 15 min following the onset of the first 3 REM episodes. Data were then averaged in order to obtain group mean values and standard deviation. The same process was applied to the 30-min epochs around REM sleep end. Results : The course of the Delta band around REM sleep onset was found to be characterized by a first phase of slow decline lasting from the beginning of our window up to a few seconds before REM onset; this phase was followed by a sudden, short decrease centered around REM onset, lasting for approximately 1.5–2 min. At the end of this phase, the Delta band reached its lowest values and remained stable up to the end of the time window. The Sigma band showed a similar course with stable values before and after REM sleep onset. The Beta and Gamma ratios also showed a 3-phase course; the first phase, in this case, was characterized by stable low values, from the beginning of our window up to approximately 5 min before REM onset. The following second phase was characterized by an increase which reached its maximum shortly after REM sleep onset (approximately 1 min). In the last phase, both Beta and Gamma ratios showed stable high values, up to the end of our time window. At REM sleep end, the Delta band only showed a very small gradual increase, the Sigma band presented a more evident gradual increase; on the contrary, both Beta and Gamma ratios showed a small gradual decrease. Conclusions : The results of the present study show a different time synchronization of the changes in the Delta band and in Beta and Gamma ratios, at around REM sleep onset, and seem to suggest that the oscillations of these parameters might be modulated by mechanisms more complex than a simple reciprocity. All these considerations point to the fact that REM sleep can be considered as a complex phenomenon and the analysis of high-frequency EEG bands and of our Beta and Gamma ratios represent an additional important element to include in the study of this sleep stage.

Middle-latency somatosensory evoked potentials (MLSEPs) were recorded from 19 scalp electrodes in ten male patients with the fragile X (fraX) syndrome and nine normal controls. One fraX patient was found presenting the so-called "giant" MLSEPs with an amplitude of N60 of about 60 microV and of 40 microV after stimulation of the right and left median nerves, respectively. Tapping of the right hand, in the same patient, induced the appearance of left parietal evoked EEG spikes. These findings further support the already suggested similarity between the epileptic picture of several fraX patients with that of the benign childhood epilepsy with centrotemporal spikes. Color mapping of the MLSEPs recorded in the remaining nine patients, when compared with the control group, showed an abnormally large N30 over the frontal regions, together with an increase in amplitude of P27, over the parietal areas, and of N60 and P100 which also presented abnormal field distributions, being represented preferentially over the frontal regions. These data could suggest the existence of a cortical dysfunction mostly involving the frontal lobes (supplementary motor area, in particular) in the fraX syndrome which could support many behavioral changes usually observed in these patients.

Summary Middle-latency somatosensory evoked potentials (MLSEPs) were recorded from 19 scalp electrodes in 19 patients with Down's syndrome (DS), in 13 age-matched normal controls and in 11 aged normal individuals. DS patients showed an increase in amplitude of P22, N30, P45, and N60. P100 latency was significantly shortened. After this potential, DS subjects showed the occurrence of a high voltage negative potential at around 100–110 msec followed by another high-voltage positive deflection; both these components showed a frontal-central distribution and were not observed in the two control groups. MLSEPs of DS subjects show peculiar alterations which could be supported by particular neurometabolic and/or neuropathologic changes.

EEG during wakefulness and sleep and somatosensory evoked potentials from the median nerve were recorded in a 3 year-old boy with hyperekplexia and his close relatives (parents and two sisters). Centro-temporal spikes during sleep were found in the patient and in the older sister, while somatosensory evoked potentials, in the patient, showed abnormally high amplitude over the centroparietal regions. Pathophysiological mechanisms of hyperekplexia are discussed and the existence of symptomatic forms is suggested.

Brainstem auditory evoked potentials were recorded in 4 subjects and pattern reversal evoked potentials in 1 subject, all with tuberous sclerosis. Alterations were found (absence or delay of components and prolonged interpeak intervals) which may suggest impaired nervous conduction also at brainstem level in patients with tuberous sclerosis.

We report a case of rhabdomyolysis with severe generalized weakness and muscle pain after administration of ritodrine hydrochloride, in a pregnant patient without history of neuromuscular disease. Laboratory tests showed an increase of blood CK value and myoglobinuria. An electromyography was performed, revealing a typical myogenic pattern and diffuse denervation activity. Muscular biopsy allowed to rule out inflammatory and metabolic myopathy. After delivery, the patient underwent intensive rehabilitation with progressive improvement of her clinical situation, until complete recovery. Three months later, both neurological assessment and CK levels were normal. This case highlights that rhabdomyolysis has to be considered even in patient treated with ritodrine alone and without history of neuromuscular disease. Therefore, muscular symptoms and CK levels should be monitored in women treated with ritodrine for premature labour.

Background.— Few studies in adolescents deal with the level of agreement between questionnaire and interview information in relation to headache symptoms. Objective.— To evaluate the validity of a self-administered questionnaire on headache for use in epidemiological studies of Italian high school students. Methods.— The questionnaire incorporated all items required for diagnosing migraine according to the criteria from the 2004 International Classification of Headache Disorders. The migraine diagnoses obtained from questionnaires were validated against the gold standard diagnoses by a headache specialist. Results.— Out of 104 students answering the questionnaires, 93 (89.4%) participated in extensive semi-structured interviews by a neurologist. The chance-corrected agreement rate (kappa) was 0.66, which is considered good. The questionnaire-based migraine diagnosis had a sensitivity of 67.3%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 73.3%. Conclusions.— The results indicate that our self-administered questionnaire may be an acceptable instrument in determining the prevalence of migraine sufferers in the northeast Italy adolescent population, useful in identifying subjects with “definite” migraine.

Summary Polygraphic sleep recordings (EEG, EMG, and EOG) were performed in two groups of epileptic subjects, six with fragile-X syndrome and six with symptomatic epilepsy. Recordings were visually scored for sleep stages and number of spikes/min. Subjects with fragile-X syndrome showed a well defined pattern of production of interictal epileptiform activity with the lowest values during REM sleep; symptomatic epileptic subjects showed less defined and more variable spike/min diagrams. The spectral analysis of the outline of such diagrams confirmed these differences showing shorter periodicties (80–100 min) in the fragile-X group compared to those of the symptomatic group (160–220 min). Finally, a model with multiple feedback circuits is proposed in order to explain the different patterns observed.

Sensory gating is defined as the brain's ability to inhibit repetitive and irrelevant incoming sensory stimuli and is supposed to be related to cholinergic transmission. Indeed, Alzheimer's disease (AD) is characterized by a cholinergic deficit that is believed to be involved in cerebral cortex hyperexcitability and short latency afferent inhibition deficit. Therefore, a sensory gating deficit may be supposed present in AD within the frame of cortex hyperexcitability and loss of cortex modulation of sensory inputs. The authors investigated whether a sensory gating deficit may be present in AD and whether this deficit may be related to the presence of neuropsychiatric symptoms (NPS) and reversed by donepezil treatment. Sensory gating was evaluated using a paired-stimulus auditory P50 event-related potential paradigm. Eighteen drug-naive probable AD patients (mean age 76.1 years; SD 5.6 years; 13 females and 5 males) and 15 healthy elderly controls (mean age 74.2 years; SD 5.4 years; 10 females and 5 males) were recruited. Sensory gating was evaluated in AD patients before starting therapy and after 1 and 3 months of donepezil treatment. Auditory P50 sensory gating was impaired in AD patients but no correlation was found between gating deficit and NPS. Moreover, AD patients displayed increased P50 amplitude when compared with healthy elderly subjects. Donepezil treatment did not improve P50 sensory gating in AD patients but decreased P50 amplitude. Patients with AD displayed an augmented P50 amplitude, in accordance with previous studies, suggesting increased cortex excitability. Donepezil does not affect P50 sensory gating but reduces P50 amplitude. Donepezil may induce P50 amplitude reduction by means of enhanced dopamine release. Indeed, it has been demonstrated that donepezil induces dopamine release "in vitro." The findings suggest that AD patients have a sensory gating impairment but the link with both NPS and the cholinergic deficit is doubtful.

Hemifacial spasm (HFS) is a movement disorder characterised by involuntary paroxysmal facial movements that usually involve the orbicularis oculi and then spread to the other facial muscles. A microvascular compression and demyelination of the seventh nerve at its exit from the brain stem is considered to be the main aetiology of HFS. In addition to rare idiopathic (cryptogenetic) cases, others causes of HFS exist: tumours or vascular malformations have been described, of both the ipsilateral and contralateral cerebellopontine angle (CPA). However, space-occupying lesions in locations other than CPA are usually not thought to be responsible for HFS. Here we describe the case of a 45-year-old woman suffering from HFS, who dramatically improved after surgical removal of a tentorial paramedian meningioma.

There are few reports about drug-related effects on PD pregnancy. We describe the case of a woman affected by PD treated with pramipexole monotherapy during pregnancy. The child, born by caesarean delivery, is healthy, whereas motor disability of the mother progressively increased to the point that levodopa therapy was necessary.

Presenilin 1 and 2 are 2 highly homologous genes involved in familial Alzheimer disease. While more than 100 mutations in presenilin 1 are known to segregate with the disease in familial Alzheimer disease, only 9 mutations of presenilin 2 have been identified to date. We report the clinical and neuropathological phenotype of FLO10, the large Italian Alzheimer kindred associated with methionine to valine substitution at residue 239 of presenilin 2. The patients showed a remarkable variability in age of onset of symptoms, disease duration, and clinical presentation. The neuropathological study of 2 patients revealed peculiar features in addition to neurofibrillary changes and A beta amyloid deposits in the neuropil and vessel wall. Ectopic neurons in the subcortical white matter, often containing neurofibrillary tangles, were found in both patients, one of whom presented with epilepsy. Furthermore, 1 patient showed an unusually high number of ghost tangles in the cerebral cortex. These observations indicate that the Alzheimer kindred FLO10 associated with M239V mutation of presenilin 2 is characterized by some peculiarities of the clinical and neuropathologic phenotype compared to sporadic Alzheimer disease.

Objectives : We examined retrospectively 19 patients with a history of clinical seizures, but normal activity or unclear epileptiform abnormalities in wake EEG recordings and obtained preliminary data for a controlled cohort study to evaluate the effects of sleep deprivation (SD) on interictal epileptic activity. Methods : Nineteen patients referred to our EEG department for diagnostic or follow-up purposes were divided in two groups on the basis of the different EEG protocols applied. The first group ( n =5) underwent two laboratory polysomnographies during afternoon naps, after SD, but the patients failed to fall asleep in one of the two occasions. The second group ( n =14) was submitted to two polysomnographies, the first without SD and the second after SD. Results : The first group of patients demonstrated focal epileptic discharges in 4 patients in which wake after SD appeared to be less activated that sleep after SD. In the second group the results obtained from the waking part of the recordings suggest a lack of activating effect due to SD. Conclusions : SD does not seem to offer greater activation than sleep alone. However, a mild SD may be a convenient activating method for inducing sleep and drowsiness without using any drug.

We describe a patient with ophthalmoplegic migraine and left sixth nerve palsy, in whom disease's onset occurred at middle age.

It has previously been demonstrated that both Myelin Basic Protein (MBP) and S-100 are released in the cerebrospinal fluid (CSF) of multiple sclerosis (MS) patients during acute phases of exacerbation of the disease. In order to investigate the pathobiological significance of the release of these two proteins into the CSF, MBP and S-100 were assayed in 10 MS patients during the five weeks following onset of an acute exacerbation. MBP was detectable in CSF during the first three weeks after exacerbation, while S-100 was detectable during the entire period of observation, at least in some of the patients. MBP reached its highest CSF concentrations during the first two weeks while S-100 did so in the third week, decreasing thereafter. This difference in time of presence of MBP and S-100 in the CSF is probably due to the different biological origin, MBP being a marker of myelin sheath injury, and S-100, more probably, of astrocytic activity.

20 subjects with severe hepatic failure have been studied by means of all night polygraphic sleep recordings. Base night recordings have been made, as well as registrations after treatment with drugs that are known to improve the clinical conditions of these patients, especially concerning the psychic performances. Base night recordings show sleep disruption, with a large amount of wakefulness at the beginning of the registrations and during the night itself; sleep stages are strongly reduced, especially REM sleep. After L-dopa treatment, these negative patterns are furthermore enhanced and the percentage incidence of the REM stage is very low; nevertheless, this behaviour goes side by side with a light improvement in psychological performances. On the contrary, therapy with lactulose seems to improve the neuropsychiatric state and the sleep organization; as a matter of fact, wakefulness is lower in the night records after lactulose treatment, whilst the percentage incidence of sleep stages tends back toward normality; REM sleep has clearly risen.

The authors describe a case where a parkinsonian symptomatology is associated with pneumoencephalographic and RISA-cisternographic findings typical of an occult normal pressure hydrocephalus. They discuss their personal contribution in the light of what has been already reported in the literature on the same subject. They conclude that a CSF dynamics disturbance among the possible physiopathogenetic mechanisms of an extrapyramidal syndrome in young subjects should be considered. On the other hand, they also emphasize the possibility that the occult normal pressure hydrocephalus may have syndromical expression which are different from the typical one initially described.

Summary The authors present a new system for the automatic detection of sleep spindles. The electronic and computer analysis are described and a comparison between automatic and visual analysis, performed by two independent readers, was carried out with the aim of evaluating the reliability of the system. Results are discussed and compared with those of different systems already described.