Valproate levels in children with epilepsy Minns, R A; Brown, J K; Blackwood, D H ...
The Lancet (British edition),
1982-Mar-20, Letnik:
1, Številka:
8273
Journal Article
Ten healthy volunteers were examined with single photon emission tomography and
99mTc-exametazime. They were studied on 2 occasions, during a 2- and a 3-sound auditory discrimination (oddball) task. ...Twenty healthy volunteers were used as controls, studied once at rest. During the 2-tone task there was a bilateral posterior (occipito-) temporal and medial frontal activation, a left pericentral increase, and posterior cingulate suppression. During the 3-sound task activation was again found in posterior (occipito-) temporal, medial frontal cortex, left pericentral, with a small non-significant reduction in posterior cingulate uptake. Compared with the 2-tone task, there was a trend towards higher activity in left medial frontal, right posterior temporal and posterior cingulate cortex in the 3-sound task. P3b amplitudes were negatively correlated with posterior cingulate tracer uptake during both tasks. Positive correlations with P3b amplitudes were found in various frontal and temporal regions. These results are consistent with more invasive localisation studies of P3b. Posterior cingulate cortex appears to be inhibited during the oddball tasks, the more so, the more restricted the range of stimuli, and the greater the task-related recruitment of neurones (P3b amplitude). As expected from its more frontal distribution, P3a amplitude was positively correlated with anterior cingulate tracer uptake, and negatively correlated with temporal cortical activity.
Seventy patients fulfilling DSM-III criteria for major depression were given the 1.0 mg overnight dexamethasone suppression test, with salivary cortisol concentrations being measured as the dependent ...variable. Using both the DSM-III and the Research Diagnostic Criteria, we categorized the patients into four groups based on increasing frequency of endogenous symptomatology. Among these four groups there were no significant differences in salivary cortisol concentrations either before dexamethasone or eight, 16, and 24 h after dexamethasone. Similarly, there were no significant differences among the groups in either the ratios of post- to pre-dexamethasone salivary cortisol or the frequencies of positive tests based on several criterion levels of cortisol for the three post-dexamethasone samples. Multiple regression analyses indicated that the Hamilton depression rating scale item "somatic anxiety" was significantly negatively related to post-dexamethasone cortisol concentrations. We conclude that, for our sample of major depressives, the salivary cortisol dexamethasone suppression test showed no utility as a laboratory correlate of depressive episodes with endogenous features.
Using three sets of clinical criteria to define borderline personality disorder (BPD), P300 (P3) and other long-latency auditory event-related electroencephalographic potentials were measured in 22 ...subjects with BPD, 32 subjects with other personality disorders, 29 schizophrenics, 22 depressives, and 74 volunteer controls. The patients with BPD were found to differ from patients with nonborderline personality disorders, having a longer P3 latency and smaller P3 amplitude. Long-latency event-related potentials were similar in the BPD and schizophrenic groups and did not differentiate patients with BPD with a concurrent diagnosis of schizotypal personality disorder from those without schizotypal personality disorder. The P3 latency and amplitude changes distinguished the BPD and schizophrenic groups from normal controls, those with major depressive disorder, and those with nonborderline personality disorders. These findings suggest that though some patients with BPD may have depressive symptomatology, they share with schizophrenics a dysfunction of auditory neurointegration.
A family is presented with multiple cases of mild mental retardation, schizophrenia and other functional psychoses, progressive hearing loss, and retinitis pigmentosa (RP). It closely resembles a ...previously reported Finnish family. We suggest that the phenotypes are not associated in this family by chance, but define a novel syndrome which may be caused by a mutant allele at a single genetic locus.
Twenty-three schizophrenic patients and 26 age-matched control subjects were studied using the P300 recorded during the auditory oddball task, with counting. Our aim was to assess the most suitable ...method of measurement and analysis of P300 amplitude and latency for use in clinical studies of schizophrenia. The effect of high-pass filtering, peak definition method and recording electrode site were all investigated. We have developed a technique, based on a least-mean-squares approximation to data, which seems particularly well suited to dealing with multi-peak P300 complexes. We have also investigated the spectral composition of the P300 and have found some evidence to support a proposed 2-frequency model of the P300 complex.
Sodium Valproate levels in plasma have been measured in 207 children with epilepsy, only 21 of whom were in-patients. No significant correlation could be found between plasma levels and dose of ...Sodium Valproate expressed as mg/day, mg/kg body weight or mg/m2 surface area. This finding could not be attributed to irregular compliance, concomitant administration of other anticonvulsant drugs, time of sampling after last dose, duration of treatment or age of the child. We could find no evidence of a therapeutic range of plasma levels of Sodium Valproate and the ranges associated with poor (17%), moderate (44%) or good control (39%) of fits were not significantly different. The average daily dose producing an improvement in seizure control was calculated to be 30 mg/kg.
Several studies have reported changes in auditory event-related potentials in patients with Alzheimer's type dementia. These include an increase in latency and a reduction in amplitude of the P300 ...(P3) response, a late positive component generated about 300 ms after an unexpected stimulus. Alzheimer's type dementia is an almost invariable acompaniment of ageing in Down's syndrome. This study was designed to assess the usefulness of the auditory P300 response as a measure of the onset of dementia in Down's subjects, who because of poor language development may be difficult to assess by psychological tests. Auditory event-related potentials were recorded from 89 Down's subjects, aged 16-66 years. A control group of 29 mentally retarded subjects with fragile-X syndrome and 83 normal volunteer controls were also tested. Clinical psychological testing found evidence of dementia in 16 Down's subjects and none with fragile-X. Furthermore, in the Down's population but not the fragile-X or control groups, there was a marked increase in P300 latency with age starting around 37 years. In controls, the effect of age on P300 latency became significant some 17 years later around the age of 54 years. The premature effect of age on P300 in Down's syndrome was due to the prolonged P300 latency in the 16 subjects showing signs of dementia. It was confirmed that P300 latency increase reflects the development of Alzheimer's dementia in Down's subjects.
Sixty-five subjects with Down's syndrome were followed up and retested 2 years after the initial recording of auditory P300 (P3) event-related potential described in a companion paper (Blackwood et ...al., 1988). The number of subjects showing clinical evidence for Alzheimer's type dementia had increased by a further 14%. In subjects showing clinical deterioration over a period of 2 years, 78% (7/9) had an increase in P3 latency which was three standard deviations or greater than the group mean. None of the 20 fragile-X group retested showed significant change after 2 years. The results suggest that P3 change may be a sensitive index of the onset of Alzheimer's type dementia in Down's syndrome.
