摘要:

The concept of rapid cycling is confusing in terms of its definition, clinical features, course of illness and the outcome. To complicate the matter further, rapid cycling has been reported to be drug resistant. Currently this condition has been reported to be secondary to lithium, tricyclic antidepressants and other agents such as cyproheptadine, a serotonin antagonist, piribedil, pro-pranolol and levodopa. The increase in rapid cycling has coincided with the rapid increase in cocaine use in the society even though such an association cannot prove a causal relationship. Clinical or subclinical hypothyroidism as well as hyperthyroidism have been implicated in rapid cycling. In addition to the lack of specific knowledge on the etiology, a number of heterogeneous disorders has been grouped under this entity. It is useful to attempt a classification to ascertain whether clinically distinguishable subgroups have a common or different pathophysiology and to tailor the treatment that is most desirable for each subgroup.

ISSN:0302-282X    

DOI:10.1159/000118980

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

The cerebral cortex of the rat possesses 5-HT1A receptor subtype; however, whether the activation of this receptor by dorsal raphe nucleus stimulation produces a similar action on neuronal cortical firing as antidepressants acting on serotonin (5-HT) function is unknown. Single-unit extracellular recordings were obtained from parietal cortex in rats in which dorsal raphe nucleus or cerebellar peduncle was stimulated. Results compared groups long-term treated with clomipramine (1.25 mg/kg i.p., twice a day, during 30 days) or saline (0.15 ml i.p., twice a day, during 30 days). Amplitude of traces, firing rate, and response to treatment with clomipramine proved to be different between cortical neurons responding to dorsal raphe nucleus or cerebellar peduncle stimulation. Clomipramine increased a long-lasting cortical suppression of firing elicited by dorsal raphe nucleus stimulation. Obtained data suggests that the responses of nearby cortical neurons containing different kinds of 5-HT receptors may relate to the involved pathways and that clomipramine seems to act on 5-HT1A receptor subtype.

ISSN:0302-282X    

DOI:10.1159/000118981

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Quantitative assessment of regional cerebral blood flow (rCBF) was performed in a 22-year-old man with intractable temporal lobe epilepsy on long-term high-dose phenytoin (PHT) therapy, using single photon emission computed tomography (SPECT) with N-isopropyl-(iodine-123)-p-iodoamphetamine. In all the SPECT scans repeated three times with changes in the PHT dose, absolute rCBF values were lower in most of the cerebral and cerebellar regions measured, as compared with 5 normal subjects matched for sex and age, and 22 normal subjects including the 5 men. Both the cerebellar to frontal rCBF ratio and cerebellar to cerebral rCBF ratio in the patient persistently showed low values, probably reflecting abnormal relative cerebellar hypoperfusion, whereas X-ray computed tomography and magnetic resonance brain imaging showed no abnormal findings. However, this probable cerebellar abnormality on SPECT was to some degree reversible with decreases in the PHT dose. These results suggest the utility of SPECT scans for early detection of cerebellar abnormalities known to be often present in epileptic patients, and imply a risk of long-term high-dose PHT therapy.

ISSN:0302-282X    

DOI:10.1159/000118982

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Vascular dementia represents a group of diseases of great medical and social impact. Its etiology is largely unknown but is most likely multifactorial. Factors related to the brain circulation are involved. The aim of the present study was to find out if personality and social background factors might have a clear precipitating or protective value. This study comprises a total population of 2,612 individuals from a geographically delimited area, Lundby, in southern Sweden. In 1957, Hagnell personally examined 99% of the population. A follow-up study of the same individuals, irrespective of domicile, was performed 15 years later. No social background factors proved to be relevant in this study. Personality factors, including psychosomatic reactions, did, however, demonstrate a highly predictive influence on the risk of developing vascular dementia.

ISSN:0302-282X    

DOI:10.1159/000118983

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

An experiment was carried out to examine the effects of coffee on performance and alertness in the day and at night. The results showed that caffeinated coffee had a beneficial effect on alertness and improved performance on a variety of tasks in both day and night sessions. The effects were often very large. For example, at night, consumption of caffeinated coffee produced comparable alertness ratings to the day-time ratings given when juice was drunk. In contrast to the effects of caffeinated coffee, the difference between the decaffeinated coffee and juice were small and variable. Overall, these results clearly demonstrate the beneficial effects of consuming caffeinated coffee, and show that this effect is comparable in the day and night.

ISSN:0302-282X    

DOI:10.1159/000118984

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Elevated levels of circulating corticosteroids are frequently associated with behavioral alterations in man, although the mechanisms by which corticosteroids may affect behavior are poorly understood. To evaluate possible effects of exogenous corticosteroids on brain electrophysiological functioning and the relationship of such effects to behavioral and biochemical changes, we administered prednisone (80 mg p.o. daily for 5 days) in a double-blind manner to 11 medically healthy volunteers. Quantitative electroencephalogram analysis was performed following 4 days of prednisone administration and during the preceding and ensuing placebo administration periods. Central theta wave brain electrical activity significantly increased following prednisone administration and returned to baseline following prednisone withdrawal. This effect was directly correlated with prednisone-induced increases in subjective sadness ratings and with decreases in self-rated energy and well-being. Prednisone-induced reductions in peak alpha wave activity were also directly correlated with increases in subjective sadness and Symptom Checklist-90 ratings and with decreases in self-rated ‘hypomanic’ symptoms. Further, prednisone-induced increases in theta activity were significantly correlated with predni-sone-induced decreases in CSF levels of somatostatin-like immunoreactivity, and prednisone-induced decreases in peak alpha activity were significantly correlated with decreases in CSF levels of norepinephrine and with relative increases (or lesser decreases) in CSF levels of β-endorphin and β-lipotropic hormone. This preliminary report of the concomitant development of prednisone-induced changes in brain electrical activity, neurochemistry and behavior highlights areas for future exploration in the study of corticosteroid effects on behavior i

ISSN:0302-282X    

DOI:10.1159/000118985

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Studies on EEG data in dementia of the Alzheimer type have mainly investigated parameters in the frequency domain. However, the EEG also reflects the momentary functional state of the brain. The EEG can be partitioned into segments of spatially stationary map landscapes as characterized by the locations of potential maxima and minima, to study the time domain of the EEG. We calculated the segment structure of 19-channel EEG recordings (1–30 Hz) from 10 patients with dementia of the Alzheimer type and 10 sex-matched geriatric controls. The EEG maps corresponding to global field power peaks were used for analysis. The locations of the potential maximum and minimum of the maps were determined over the course of 20 s and used for segmentation. The segments of EEG activity were significantly fewer (p < 0.05) and the segments lasted longer (p < 0.05) in patients compared to controls. This effect could be observed over the whole period of recording and thus was not caused by only a few long segments. The data may be linked to morphological and biochemical findings of neuronal loss and loss of synapses in dementia of the Alzheimer typ

ISSN:0302-282X    

DOI:10.1159/000118986

出版商:S. Karger AG    

年代:1993

数据来源: Karger

ISSN:0302-282X    

DOI:10.1159/000118987

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

The influence of magnesium, one of the most important cations in the vertebrate body, on the sleep-wakefulness cycle and ECoG patterns in chronically implanted rats recorded during the light period over a 6-hour period was investigated. Two groups of rats were studied. Group 1 (6 rats): after a control period of 2 weeks, the rats were maintained for 9 weeks on a Mg2+-deficient diet. Group 2 (5 rats): after a control period of 2 weeks, the rats were maintained for 7 weeks on a Mg2+-deficient diet followed by 4 weeks on a normal diet (recovery period: weeks 8–11). Mg2+-deficient diet for 9 weeks induced sleep and ECoG time-dependent alterations. After 6–7 weeks on a Mg2+-defi-cient diet (n = 11) sleep analysis showed a significant increase of wakefulness (+50%) at the expense of slow wave sleep (–24%) but paradoxical sleep was not significantly modified. After 9 weeks of a Mg2+ deficient diet, sleep was desorganized: light sleep and polyspikes occurred indicating an increase in neuronal excitability. When Mg2+ was reintroduced in food and water, sleep organization and ECoG recordings were restored to their original patterns. Our findings which are in line with previous clinical and pharmacological observations provide conclusive arguments for the neuroprotective effect of magnesium ions in neurologic disorders and epileptiform activity. Mg2+ deficiency induces ECoG alterations in the rat which bear some similarities with those seen in neurogenic spasmophilic syndromes i

ISSN:0302-282X    

DOI:10.1159/000118988

出版商:S. Karger AG    

年代:1993

数据来源: Karger

ISSN:0302-282X    

DOI:10.1159/000118989

出版商:S. Karger AG    

年代:1993

数据来源: Karger