The effect of Althesin on local blood flow in the brain was studied using intra-carotid Xenon 133 in 18 subjects: 6 apparently normal, 6 with diffuse cerebro-vascular pathology, and 6 cases of ischaemic cerebral accidents identified by scintigraphy, tomodensitometry and angiography. Blood flow decreased under Althesin in the first 2 groups, although to a lesser extent in the second group, with a concomitant decrease in oxygen metabolism. In the third group a "paradoxical" increase in blood flow was observed in infarcts, and a decrease proportional to the rest of the brain in limited ischaemia which had subsequently regressed. The "Althesin test" proposed by Rasmussen (1975) thus reveals the existence of a disconnection between blood flow and metabolism within cerebral infarcts, and provides a possible means of differentiating the latter from reversible ischaemias.

Alfaxalone Alfadolone Mixture↗

PubMedDate not supplied

[Severe vigilance disturbances: a rare complication of sodium valproate treatment (author's transl)].

Severe vigilance disturbances are rarely observed during sodium valproate treatment. Two such cases are reported, with rapid appearance of mental confusion after starting treatment, associated with an overall slowing of the E.E.G. the plasma levels of the different anti-epileptic agents were normal or only slightly raised and could not have caused the phenomenon. Clinical and electrical signs regressed as rapidly after stopping valproate administration as they had appeared after starting treatment.

Adult↗

PubMedDate not supplied

Double-blind, placebo-controlled study of vigabatrin (gamma-vinyl GABA) in drug-resistant epilepsy.

Vigabatrin (GVG) (3 g/day) and placebo were compared as an add-on to standard therapy in therapy-resistant epileptic patients using a double-blind crossover design with randomized treatment allocation. Twenty-three patients entered the trial, with four dropping out due to either increased seizure frequency following the cross-over from GVG to placebo (n = 1), intolerance to GVG therapy (n = 2), or poor seizure record (n = 1). Of the 19 patients who completed the study, 17 had partial seizures, eight of whom had secondary generalization and two who had primary generalized seizures. Compared with placebo, GVG was associated with a significant reduction in seizure frequency (p less than 0.01), with 11 of 19 patients experiencing greater than 50% reduction in weekly seizure occurrence, two showing a 25-50% reduction, four unchanged, and two showing an increase in seizures. Global efficacy ratings were greater in the GVG period for 15 patients (p less than 0.05) compared with one in whom there was no period difference and two in whom ratings were higher in the placebo period. Fourteen of the 19 patients indicated a preference for the GVG period. Adverse effects observed during GVG treatment were generally mild and consisted of drowsiness, confusion, nausea, irritability, and constipation. No clinically significant alterations in laboratory test results were observed. No treatment-related changes in plasma concentrations of concomitant antiepileptic drugs were noted. These results confirm the antiepileptic efficacy of oral GVG in refractory epileptics.

Adolescent↗

PubMedDate not supplied

Eating seizures.

An 18-year old man had a cluster of three seizures in a few hours and then remained seizure-free without medication; his mother has experienced seizures induced by movement. A 29-year-old man has had recurrent seizures for six years. In both cases, seizures were partial motor seizures induced by chewing. They are considered to be a particular variety of movement-induced seizures triggered by proprioceptive afferents of muscular origin. This explanation does not account for the great majority of the 63 published cases of seizures precipitated by eating. Eating seizures represent a heterogeneous group of seizures with discrete electroclinical signs and mechanisms. The term "eating seizures" should be preferred to the term "eating epilepsy."

Adolescent↗

PubMedDate not supplied

Prognosis of benign childhood epilepsy with centrotemporal spikes: a follow-up study of 168 patients.

A spontaneous and complete recovery of benign childhood epilepsy with centrotemporal or rolandic spikes (BECT) is taken for granted. However, some authors have reported the occurrence of generalized tonic-clonic seizures in a few adult patients and in some children who have seizures after a long period without problems. The aims of this study were (a) to search for early predictors of outcome and (b) to ascertain the long-term prognosis of BECT in a large group of patients. An attempt to relocate 268 patients born between 1941 and 1967 and consecutively seen as outpatients was undertaken. The outcome after age 20 is known for only 168. Being adults and cured, the others are no longer in touch with their clinics or have moved. Only one indicator of short-term prognosis was found: The earlier the onset of BECT, the longer the period with seizures. Of the 168 patients, 165 are seizure-free with follow-up ranging from 7 to 30 years. Three patients experienced generalized tonic-clonic seizures at age 18, 22-24, and 35. Two apparently had an isolated seizure. The occurrence of such seizures after recovery from BECT is a rare event (approximately 2% of cases) and a relapse with partial seizures is quite uncommon. These patients do not differ from patients remaining seizure-free.

Adult↗

PubMedDate not supplied

Quinolinic-phosphoribosyl transferase activity is decreased in epileptic human brain tissue.

The presence of the excitotoxic and convulsant agent quinolinic acid (QUIN) in human brain has led to the hypothesis that an increase of this tryptophan metabolite could serve as an endogenous epileptogen. A possible mechanism for a pathological accumulation of QUIN being a deficiency in its degradation, we have measured the activity of quinolinic-phosphoribosyl transferase (QPRTase) (its first degradative enzyme) in stereo-EEG identified biopsies of human brain tissue. A specific reduction of QPRTase activity was observed in tissue primarily involved in the epileptic discharge compared to values from postmortem human brain tissue with no neurological disorders or nonpathological tissue from epileptic brains. A more severe decrease was noticed in the frontal and temporal cortices as compared to the amygdala or Ammon's horn. We suggest that this local deficit may contribute to the establishment or maintenance of an epileptic focus.

Adolescent↗

PubMedDate not supplied

Survey of seizure disorders in the French southwest. I. Incidence of epileptic syndromes.

An epidemiologic survey began on March 1, 1984, and ended on February 28, 1985. During this period, all neurologists and electroencephalographers of the department of Gironde, an administrative district of the French Southwest (1,128,164 residents in 1982) obtained information by questionnaire from all persons who had experienced an epileptic seizure for the first time in their lives. Recurrent, isolated, and situation-related seizures were included. Febrile convulsions and neonatal seizures were excluded. The global incidence rate of diagnosed epileptic seizures was 71.3/100,000. The incidence rates per year and per 100,000 persons by type of epileptic syndrome were 1.7 for idiopathic and 13.6 for symptomatic localization-related epilepsies, 5.6 for idiopathic and 1.1 for symptomatic generalized epilepsies, 1.9 for undermined epilepsies, 29.0 for situation-related seizures, 18.3 for isolated seizures, and 0.3 for television epilepsies. Other epileptic syndromes were not represented. Using a classification of epileptic syndromes and not of epileptic seizures reduces difficulties in an epidemiologic survey. Diagnosis of an epileptic syndrome is time dependent, however, and at follow-up some patients shift from one group to another.

Epilepsy↗

PubMedDate not supplied

Classification of epilepsies and epileptic syndromes in two different samples of patients.

We attempted to classify, according to the International Classification of Epilepsies and Epileptic Syndromes, 986 patients consecutively examined during a 13-month period either in a specialized private practice (n = 642) or in an adult neurology unit in a university hospital (n = 344). Without major difficulty, we classified 97% of patients in more or less clearly defined syndromes. Benign frontal and benign psychomotor epilepsies of childhood were represented in this sample of patients. In either partial or generalized idiopathic epilepsies, a diagnosis of epilepsy appears justified even after a single epileptic event when sufficient electroclinical characteristics are present. Patients with symptomatic generalized epilepsies often have to be classified under two or three headings. Many children with a symptomatic generalized epilepsy also experience partial seizures. Alcoholic epilepsy is described as a veritable epileptic syndrome. The distribution of epileptic syndromes was clearly different in the two samples, casting doubt on the value of some epidemiologic surveys based on selected groups of patients.

Adolescent↗

PubMedDate not supplied

Diurnal variations in steady-state plasma concentrations of valproic acid in epileptic patients.

Patients on long term valproate treatment exhibit unusual fluctuations in steady-state plasma levels of valproic acid. In order to delineate the underlying mechanisms of these fluctuations, 2 studies were undertaken. In the oral study, 6 epileptic patients received enteric-coated sodium valproate tablets (on a bid regimen for at least 1 month) and plasma levels were monitored on an hourly basis during 24 hours. In the intravenous study, 5 patients received first an intravenous bolus dose (800mg) of sodium valproate followed a week later by a combination intravenous loading dose/constant rate infusion for 36 hours. Plasma valproic acid concentrations were monitored hourly during the infusion study. In the oral study, valproic acid concentrations in all subjects continued to decay for 5 to 6 hours following the 8pm dose. The mean fluctuation in concentrations during 24 hours was 112.8 +/- 31.6%. Consecutive fasting levels were not reproducible. In the intravenous study, small but significant oscillations were present at steady-state; fluctuations ranged from 22 to 34%. However, no circadian rhythm was apparent. On the basis of these findings, it appears that the value of a single fasting sample during therapeutic monitoring of valproic acid is questionable. For an accurate evaluation of valproic acid plasma levels, an average concentration based upon several daily determinations should be performed.

Administration, Oral↗

PubMedDate not supplied

Model systems for metabolism studies. Biomimetic oxidation of acetaminophen and ellipticine derivatives with water-soluble metalloporphyrins associated to potassium monopersulfate.

Some original water-soluble metalloporphyrins/KHSO5 systems were developed to mimic the metabolic biooxidation of drugs. Oxidation of acetaminophen and various ellipticine derivatives were used as model reactions. Oxidative products (mainly quinone-imine structures) were obtained in good yield after 2 min of reaction, for a catalyst/substrate ratio of 0.04. Iron(III) derivative of tetrasodium meso-tetrakis(p-sulfonatophenyl)porphyrin and manganese(III) derivative of tetraacetate meso-tetrakis(4-N-methyl-pyridiniumyl)-porphyrin were the best catalysts for the oxidation of acetaminophen and ellipticine compounds, respectively. At low catalyst concentration, initial turnover rates could rise up to 8 catalytic cycles/sec. In some conditions, these catalytic systems are nearly as efficient as horseradish peroxidase/H2O2. They might have a real future as oxidation catalysts, in complement to the use of purified monooxygenase and peroxidases, to predict the possible in vivo oxidative metabolite pathways.

Acetaminophen↗