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 43 patients, aged 15 to 69 years, whose convulsive seizures were uncontrolled because the syndrome of juvenile myoclonic epilepsy was not recognized. Awakening myoclonic jerks appeared with tonic-clonic (18 patients), clonic-tonic-clonic (24 patients), and absence seizures (17 patients), with a mean age at onset of 13.6 years. Generalized seizures were present in relatives of 17 patients. All patients had diffuse 3 1/2- to 6-Hz multispike-wave complexes. Valproic acid stopped convulsions in 86% of patients. After being free of seizures for 2 years, withdrawal of valproic acid was followed by relapse of convulsions in 12 patients.
 ...
PMID:Juvenile myoclonic epilepsy of Janz. 642 21

The purpose of this study was to compare three different modes of treatment in the prevention of relapses of febrile convulsions (Phenobarbital = PH, Sodium Valproate = SV, Placebo = PO) in a randomized therapeutic trial. The patients included in the study had shown their first generalized convulsive seizure during a bout of fever (greater than or equal to 38.5 degrees C) and were aged between 6 months and 4 years. They were subsequently followed up as outpatients, and Phenobarbital and sodium valproate levels were measured regularly to ascertain compliance with the treatment and to adjust the dosage accordingly. The patients' families were questioned with respect to the occurrence of feverish bouts and convulsive seizures during the interval between visits, as well as possible adverse reactions. An EEG was carried out yearly. Results were as follows: - 69 patients - 35 boys and 34 girls - with an average age of 24 months were divided into 3 groups according to treatment: 21 cases on PH, 22 cases on SV, and 26 cases on PO. - they were followed up for an average duration of 21 months. - the average number of feverish bouts per child and per year was evaluated at 2.5, no statistically significant difference being noticeable between the various modes of prophylaxis. - 15 relapses of febrile seizures were noted in 14 children, over an average duration of 23 months; on average, relapses occurred after 9 months; among the 14 children who had relapsed, one had been treated with SV, 4 with PH and 9 with PO, leading to estimated relapse rates of 4%, 19%, and 35% respectively. There is a statistically significant difference in the relapse rates between the treated groups (SV and PH) and the Placebo group, and a particularly significant difference between Sodium Valproate and Placebo.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Prevention of recurrent febrile convulsions--a randomized therapeutic assay: sodium valproate, phenobarbital and placebo. 642 41

In gerbils, 'minor' (myoclonic) and 'major' (clonic-tonic) seizures were induced by blowing at the animals with compressed air. The anticonvulsant ED50 of the following drugs was determined after oral administration against both types of seizures: phenytoin, phenobarbital, carbamazepine, sodium valproate, ethosuximide, and diazepam. Valproate, ethosuximide, and diazepam were most potent against 'minor' seizures which could not or only partially be suppressed by phenytoin or carbamazepine, respectively. The 'grand mal' drugs phenytoin, phenobarbital, and carbamazepine were, on the other hand, more potent against 'major' than against 'minor' seizures. When phenobarbital was administered for several days, a strong induction of hepatic microsomal enzymes occurred.
 ...
PMID:Anticonvulsant potency of common antiepileptic drugs in the gerbil. 642 44

Sodium valproate was administered to 38 patients, admitted to our unit in the last 18 months, and chosen because they had: (1) poor control of their seizures; (2) therapeutic concentrations in their plasma of at least two major antiepileptic drugs. In 8 of them, a therapeutic dosage of VPA caused modifications of the state of consciousness ranging from coma to drowsiness and stupor. These patients also showed gastrointestinal disturbances, asterixis, ataxia, tremor and a worsening of EEG abnormalities. The side effects of the drug were constantly associated with increased concentration of blood ammonia. Better penetration of ammonia into the CNS of patients undergoing frequent seizures and possibly having imperfectly functioning biological barriers, could explain our observations. In view of the unusually high percentage of patients suffering from serious VPA side effects, it is probably advisable to carefully monitor ammonemia in the first few days of VPA therapy in every patient treated with multiple anticonvulsants.
 ...
PMID:Hyperammonemia and valproate-induced alterations of the state of consciousness. A report of 8 cases. 642 61

Valproate and the branch-chain valproate analogues, 2-propyl-hexanoate and 2-ethyl-hexanoate, block sound-induced seizures in DBA/2 mice following their intracerebroventricular administration, the ED50 values for the suppression the clonic phase of the seizures being 6.0, 5.0, and 10.2 mumoles respectively. The straight-chain analogues, butyrate and pentanoate , have no anticonvulsant activity. Systemic administration of branched-chain valproate analogues has previously shown a progressive increase in the anticonvulsant activity of the analogues with an increase in the chain-length of the molecules. This relationship is abolished when the same analogues are injected directly into the ventricles. The icv administration of the 2 straight-chain, inactive analogues produces no effect on brain aspartate and GABA levels (with the exception of a butyrate-induced 34% rise in forebrain GABA level). There is a dose-dependent decrease in aspartate levels in cerebellum and forebrain (up to 45-55% reduction), and a dose-dependent increase in GABA levels in forebrain (up to 30-75% rise) 30 min after the icv administration of the 3 anticonvulsant branched-chain fatty acids. 2-Propyl-hexanoate does not affect the cerebellar GABA level significantly, while valproate and 2-ethyl-hexanoate administration produce 20-40% increases in cerebellar GABA levels.
 ...
PMID:Anticonvulsant activity of intracerebroventricularly administered valproate and valproate analogues. A dose-dependent correlation with changes in brain aspartate and GABA levels in DBA/2 mice. 642 19

The cell membrane-disordering potencies of sodium valproate, the sodium salts of other short-chain fatty acids, and ethanol were compared using fluorescence polarization with the probe 1,6-diphenyl-1,3,5-hexatriene. Valproate was about 7 times more potent in fluidizing synaptosomal plasma membranes than ethanol, a prototypic disordering agent. The disordering potency of the straight-chain fatty acids pentanoate through octanoate increased by a factor of 2.2 with each additional methylene group. The sedative potencies of the drugs were assessed by determining the brain concentration at which Swiss Webster mice lost the ability to balance on a stationary wooden dowel. Relative anticonvulsant potency was measured by determining the ED50 for protection against pentylenetetrazol-induced seizures and then determining the brain levels of drug that were actually achieved at the time of seizure protection. The ability of the fatty acids and ethanol to disorder membranes in vitro correlated closely with their ability to cause sedation and protect mice against pentylenetetrazol-induced seizures. These data suggest that valproic acid might exert some of its effects by disordering brain cell membranes--the proposed mechanism of action of ethanol and the general anesthetics.
 ...
PMID:Membrane-disordering potency and anticonvulsant action of valproic acid and other short-chain fatty acids. 643 Dec 62

Valproic acid serum concentrations predicted by a single-dose prediction model were compared with steady-state serum concentrations measured after the start of therapy in seizure patients. Ten patients receiving valproic acid for the first time or who had not been taking the drug for two or more weeks were entered into the study. The patients' therapies were initiated with the prescribed doses of valproic acid and then maintained on fixed doses and dosing intervals until steady-state trough serum samples were obtained. Initial 5-ml blood samples were collected six to 14 hours after the ingestion of the first dose; a 5-ml steady-state trough sample was drawn in the same manner three to seven days later. Both free and total drug concentrations were determined within 48 hours of sample collection using gas-liquid chromatography. The elimination rate constant was estimated from age-specific population half-life values found in the literature. Six patients (five children, aged four to 16 years) and one adult (aged 87 years) completed the study. There was a statistically significant correlation between predicted and measured steady-state valproic acid serum concentrations for both free and total concentrations. The single-dose prediction model accurately predicted steady-state valproic acid serum concentrations in these seizure patients.
 ...
PMID:Single-dose model for predicting steady-state valproic acid serum concentrations in seizure patients. 643 55

The anticonvulsant effect of either phenobarbital or dilantin was potentiated by exogenous glycine in DBA/2 audiogenic seizure mice and in 3-mercaptopropionic acid-induced seizures. In seizures caused by pentylenetetrazol, glycine potentiated the anticonvulsant effect of phenobarbital only slightly; in combination with dilantin, which was ineffective by itself, it did not have an effect. Valproic acid, in large doses, prevented 3-mercaptopropionic acid-induced seizures; glycine did not potentiate its effect. Glycine thus potentiates anticonvulsant effects, but only of some drugs and only in some of the seizure models. This suggests that the mechanism of the anticonvulsant effect of glycine is similar to that of some of the anticonvulsant drugs such as dilantin and different from others, and that this mechanism is not effective in all seizure models.
 ...
PMID:Glycine potentiates the action of some anticonvulsant drugs in some seizure models. 644 97

Sodium dipropylacetate, an anticonvulsant used in human therapy, gives a more efficient protection against convulsions elicited by pentetrazol than by picrotoxin. In the case of picrotoxin induced convulsive seizures where there is an alteration at the GABA receptor level, ther is a lack of efficiency after nDPA treatment which increases GABA at the synaptic level. DPA is more effective against pentetrazol convulsive seizures where no direct participation of GABAergic receptors seems to occur. The efficiency of potentialisation of GABAergic mediation is a function of the mechanism by which the seizure is triggered.
 ...
PMID:[Effect of sodium dipropylacetate on experimental convulsions produced by pentetrazole and picrotoxin]. 645 30

The effect of ethosuximide, dipropylacetate and clonazepam on metrazol convulsions induced by a dose of 80 mg/kg was studied in 314 male albino rats aged from 5 days to adult. In a standard dose of 125 mg/kg, ethosuximide reliably protected only adult and 25-day-old rats, i.e. the age groups in which a mature minimal seizure was the only type of convulsion induced; in younger animals, not even a much higher dose (tested in 12-day-old rats) afforded reliable protection. Dipropylacetate and clonazepam had a manifest protective effect in all age groups, irrespective of the type of seizure. Isolated myoclonic jerks were less sensitive to antiepileptics and only dipropylacetate blocked them in the youngest age groups. In 21-day-old and older animals dipropylacetate induced stereotype head movement reminiscent of the serotonergic stereotypy described in the literature.
 ...
PMID:Effect of antiepileptic drugs on metrazol convulsions during ontogenesis in the rat. 645 49


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