Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0036572 (seizures)
 80,221 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied the relationships between clinical variables and those related to the states of vigilance in 18 cases of benign partial epilepsy with centro-temporal spike-waves, 22 cases of definite symptomatic partial epilepsy, and 16 cases of undetermined partial epilepsy. The time of day during which the seizures appeared and the paroxysmal activity densities during non-REM and REM sleep are not distributed differently among the 3 electro-clinical types. However, the benign epilepsy with centro-temporal spikes group had more patients with sleep-sensitive paroxysmal activities. Patients who mainly had nocturnal seizures were found to have more frequent generalized seizures and a greater sleep-sensitive paroxysmal activity. Three cases demonstrated continuous spike-waves during sleep. The patients who had little or no paroxysmal activity during sleep were the youngest. This study illustrates that sleep-sensitive seizures and paroxysmal activities are not specific to benign childhood epilepsy with centro-temporal spikes, and that seizures and paroxysmal activities are two manifestations associated with epilepsy, affected in different ways by states of vigilance.
 ...
PMID:The influence of vigilance states on paroxysmal EEG activities and clinical seizures in children. 168 35

We studied the relationships between epilepsy, sleep, and anticonvulsant drugs in kindled cats. No sleep alteration was present at midkindling. When the animals became fully kindled, a reduction in REM sleep percentage and the number of entries into REM sleep were observed compared to baseline. In addition, with further seizures, an increase in the percentage of wakefulness appeared, accompanied by a further reduction in the number of entries into REM sleep. It therefore seems that there is a progressive disruption of sleep, dependent on the increasing number of tonic-clonic generalized seizures. After a seizure-free interval, REM sleep and wakefulness returned to baseline values. A reduction in the percentage of stage II compared to baseline was found and remained as a long-term effect of the kindling process. Acute administration of carbamazepine (CBZ) reduced the REM sleep percentage. This effect, paralleled by a reduction in the number of entries into REM sleep, was evident both at baseline and when the animals were fully kindled. After a large number of seizures, however, CBZ administration did not cause a further reduction in the already low percentage of REM sleep. Results are discussed with reference to previous literature. We propose a hypothesis of competition between seizure and REM sleep in the elimination of epileptogenic and hypnogenic factors.
 ...
PMID:Effects of seizures, kindling, and carbamazepine on sleep organization in cats. 173 48

The occurrence of spike-wave discharges was studied in relation to the daily fluctuations of vigilance level in rats. Eight rats of the WAG/Rij strain, an animal model for idiopathic generalized epilepsy of the absence type, which were equipped with cortical EEG and nuchal EMG electrodes, served as subjects. It was found that spike-wave discharges predominantly occur during light slow wave sleep and passive wakefulness. REM sleep, active wakefulness, and deep slow wave sleep are less susceptible to the occurrence of spike-wave discharges. Finally, spike-wave discharges tend to prevail in transitional states. A crucial role for the degree of stability of the level of vigilance in the genesis of absence seizures is suggested.
 ...
PMID:Spike-wave discharges and sleep-wake states in rats with absence epilepsy. 174 84

The correlations between sleep and prolonged epileptic activity are discussed on the basis of the status classification of Gastaut (1983). Little information is available on the interrelation of sleep and the status of tonic-clonic seizures (grand mal status). Most important is the therapeutical management of these cases. Tonic seizures have been reported to occur in large numbers during NREM sleep in patients with Lennox-Gastaut syndrome. A status-like increase is possible. Tonic seizures occur almost exclusively during sleep. Myoclonic status epilepticus arising (a) in the course of primary generalized epilepsy and (b) in the course of encephalopathies, are usually markedly attenuated during sleep. In absence status (petit mal status) synchronized sleep generally fragments the continuous discharge which is replaced by isolated bursts of polyspikes, or polyspike and wave complexes. The absence status can recur upon awaking during the night or in the morning. The abnormal EEG activity of a petit mal status can, however, occasionally persist during the whole night. Improvement as well as activation during sleep have been observed in elementary (= simple) partial status epilepticus; improvement seems to be more frequent. Epilepsia partialis continua may persist or decrease during sleep. An increase as well as decrease of motor phenomena has been observed during the REM stages. 'Epileptic aphasia' of childhood is associated with subclinical bioelectric status epilepticus during sleep. The electrical status epilepticus must be delineated as a separate group. The term encephalopathy related to electrical status epilepticus during slow sleep (ESES) has been proposed on the basis of associated psychic syndromes. This form of status epilepticus disappears during the waking state and during REM sleep. Cases with hypsarrhythmia without clinical signs may also be classified under the group of electrical or bioelectrical status. In some cases, a continuous hypsarrhythmia is observed only during sleep. In this context, one must also mention those patients who demonstrate continuous activation of spikes, or spike and wave potentials (without clinical seizures) during eye closure.
 ...
PMID:Sleep and prolonged epileptic activity (status epilepticus). 176 86

All night sleep deprivation prior to an EEG registration causes some inconvenience not only to the organization of the EEG department but presents a burden on the patients as well as their family members, and for these reasons is not suitable to be frequently employed as a routine procedure. As an alternative, we performed short-term sleep recordings in the early afternoon following a partial sleep deprivation of the patients during the preceding night. This method was well accepted by the patients and their family. Our only goal was to shorten the total time of night sleep using the following guideline: for very small children 22.00-06.00; for 4-14-year-old patients 24.00-06.00; and for patients older than that 01.00-06.00. 79.9%, out of 719 patients (573) who had been given the above instructions subsequently showed sleep patterns in their EEG. Additionally we had to administer an oral dose of promazine to only 67 patients. However, for the most part, patients showed only light sleep stages: 114 patients only reached sleep stage 1; 323 patients sleep stage 2; 88 patients sleep stage 3; and 48 patients sleep stage 4. As expected, REM sleep was never recorded. Nonetheless, in 32 out of 146 patients who were tired but unable to fall asleep, epileptic patterns could be provoked. In 636 patients, the EEG-recording after sleep reduction was ordered because of a suspected seizure disorder; in the remaining patients it was initiated solely because of sharp components in the routine-EEG. In 341 (53.6%) of the patients with suspected epilepsy, electroencephalographic activity indicative of a seizure disorder was activated. Such epileptic patterns were recorded almost exclusively in stages of waking, 1 and 2. Only in one out of the 124 patients who reached sleep stages 3 and 4 epileptic patterns were not seen until deep sleep was entered. We observed 2/s, 3/s and 6/s spike-and-wave complexes, sharp waves, spikes, polyspikes, groups containing remarkably sharp components and so called sharp vertex grapho-elements. Patients with suspected seizure disorders frequently show grapho-elements which can be interpreted as the expression of a disposition for epilepsy. These sharp vertex elements were evident in 54 out of 719 short term sleep recordings, more often in children than in adults. 49 times they coincided with typical epileptic discharges such as sharp waves, spikes or spike-and-waves in the same recording.
 ...
PMID:Short-term sleep EEG recordings after partial sleep deprivation as a routine procedure in order to uncover epileptic phenomena: an evaluation of 719 EEG recordings. 176 90

Thirteen patients suffering from severe partial epilepsy and potential candidates for surgical treatment were investigated with stereotactically implanted intracerebral electrodes during nocturnal physiological sleep. The recorded electrocerebral activity was automatically analyzed to gain information on interictal epileptic events during wakefulness and the phases of sleep. The interictal epileptic activity shows: (1) great variability in the different subjects, and intra-individually, variability according to the explored cerebral regions; (2) is not influenced by the location of the recorded epileptic events; and (3) is affected by the local level of epileptogenicity. The latter was determined by the assessment of the capacity to give origin to ictal discharges and the disappearance of seizures following surgical removal. The interictal rate of spiking from the most epileptogenic cerebral zone is characterized by a relative stability during the night and by a relatively high degree during REM sleep.
 ...
PMID:Sleep and epileptic activity. 176 91

Sleep is known to facilitate epileptic manifestations but can also protect the sleeper against the recurrence of seizures. This has been demonstrated in studies on sleep deprivation, and is particularly evident in alcoholic epilepsy and matutinal myoclonus epilepsy. Sleep organization in the epileptic patient is permanently altered by frequent awakenings and stage shifts. Nocturnal grand mal and repetitive partial seizures worsen the sleep disorder by reducing total sleep time and decreasing REM percentage by half. The cumulative effect of these sleep disorders may act on day-time vigilance in epileptics, and may even exert an influence on the recurrence of seizures.
 ...
PMID:Sleep organization and epilepsy. 176 99

Both interictal and ictal EEG phenomena are commonly activated by functional instability. The different non-REM sleep stages comprise long-lasting periods of cyclic alternating pattern (CAP) in which arousal fluctuates between 'A phases' of greater arousal and 'B phases' of less arousal, and periods in which vigilance maintains a tonic stability (non-CAP). Previous studies have revealed that phase A induces a marked enhancement of generalized EEG paroxysms, a minor though significant activation of focal lesional bursts, but no effect on rolandic functional spikes. Conversely, phase B exerts an inhibitory modulation, especially on bilateral interictal phenomena. Because of the opposite influence of phase A and phase B also on muscle tone, we assessed the amount and distribution of nocturnal partial motor seizures in 6 subjects affected by focal epilepsy. The polysomnograms included 45 motor seizures, 43 of which occurred during non-REM sleep. Nocturnal fits were significantly more frequent in stages 1 and 3 (P less than 0.0001). Among the non-REM seizures, 42 appeared in CAP (P less than 0.0001) and always in phase A. The transient arousal and the concomitant muscle tone activation expressed by phase A of CAP is likely to support the motor components of nocturnal seizures. Sleep analysis in terms of CAP and non-CAP provides a better understanding of the continuum from subclinical EEG paroxysms to clinical manifestations and of the relations between vigilance and seizure disorders.
 ...
PMID:Activation of partial seizures with motor signs during cyclic alternating pattern in human sleep. 181 56

Spontaneous changes in interictal spike morphology were evaluated before initiation of antiepileptic drug (AED) therapy in 38 children with uncontrolled partial seizures. Nonrapid eye movement (NREM) sleep during the first third of the night was associated with spikes of higher amplitude, longer duration, and lower degree of sharpness than those observed in wakefulness or REM sleep. Spike amplitude decreased in subsequent NREM epochs, but duration and sharpness remained relatively consistent. A NREM/REM modulatory pattern was identified, with REM periods exhibiting spikes of decreased amplitude, shorter duration, and increased sharpness as compared with NREM periods in each third of the night. The spike changes associated with REM sleep are similar to the alterations previously described as occurring coincidentally with attainment of seizure control and thus may reflect inherent modulation of epileptogenicity in synchrony with sleep cycles.
 ...
PMID:Sleep modulation of interictal spike configuration in untreated children with partial seizures. 190 44

Electrical status epilepticus during sleep (ESES) is primarily an EEG-defined syndrome in children characterized by the occurrence of continuous spike and slow waves during non-rapid-eye-movement (non-REM) sleep, the paroxysmal abnormalities being substantially less frequent during the awake state and REM sleep. Etiologically, cases can be divided into symptomatic and cryptogenic varieties. Partial motor seizures, frequently nocturnal, precede the emergence of ESES, whereas absence seizures often occur during the phase of ESES. The emergence of ESES is associated with neuropsychological regression. The characteristic electrographic pattern and epilepsy generally disappear during adolescence and are associated with an improvement in neuropsychological function. However, if the cases reported in the literature are representative, then there is a high probability of considerable residual dysfunction. A number of factors, broadly termed ascertainment biases, likely contribute to the paucity of reports from North America and the greater recognition of the syndrome in Europe and Japan. The current information on ESES is critiqued in this review.
 ...
PMID:Electrical status epilepticus during slow-wave sleep: a review. 191 35


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>