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)

The biological control of insulin is vital as it is administered daily to a large proportion of the population during the major part of their lives. The development of the biological assay of insulin will be described with the progressive evolution of methods eventually to dispense with the need for animals. From the quantal Mouse Convulsion Method using around 600 mice per sample to the quantitative Mouse Blood Glucose method using an average of 120 mice per sample in which the fall in the blood glucose levels is used to estimate the potency of insulin by its hypoglycaemic effect. This was followed by the development of the in vitro Radioreceptor Method which is a procedure based on competition between the binding of insulin and [125I]-insulin to cells of the cultured human IM-9 cell line. The production of highly purified insulin by the Pharmaceutical Industry has made possible the recent introduction of new High Performance Liquid Chromatography technology.
 ...
PMID:The reduction of the number of animals used in the biological assay of insulin. 353 68

A historical cohort study was undertaken to determine the risk of epilepsy in a population of 18 newborns with neonatal hypoglycemia due to insulin excess. Follow-up was 3 years 8 months (range 7 years-1 year 3 months). Insulin excess was associated with maternal diabetes in 13 infants, with an isolated macrosomia in 2 infants, in one case with probable Langerhans hyperplasia, and in 2 newborns only prolonged beta-sympathomimetic therapy was the possible cause of insulin excess. Newborns with anoxia, brain malformation or small for date were excluded. Two newborns had hypoglycemia with epileptic clonic seizures, but only one was later epileptic. In this case, hypoglycemia was severe and persistent (16 hours). Hyperinsulinism was related to Langerhans hyperplasia. CT scan made at ages one and 6 months showed large hypodensity of the frontal and occipital white matter. Visual evoked responses were also abnormal. Visual evoked responses and CT scan normalized at 1 year. In other children, asymptomatic hypoglycemia (n = 11) or symptomatic hypoglycemia without epileptic seizures (n = 5) did not increase the epileptic risk as none of them had epileptic seizure later on. Thus, seizures associated with neonatal hypoglycemia alone seem to increase the epileptic risk with duration and severity of hypoglycemia being also essential prognostic factors.
 ...
PMID:[Neonatal hypoglycemia caused by hyperinsulinism and subsequent epilepsy]. 357 76

A new clinical entity that is prevalent in young type I (insulin-dependent) diabetic patients, postexercise late-onset (PEL) hypoglycemia, is described. A prospective case-finding study suggested that PEL hypoglycemia occurred in 48 of approximately 300 diabetic type I patients who were diagnosed as diabetic before age 20 yr and who were monitored for up to 2 yr. Typically, hypoglycemia was nocturnal and occurred 6-15 h after the completion of unusually strenuous exercise or play. In more than half the cases the hypoglycemia resulted in loss of consciousness or seizures and necessitated treatment with subcutaneous glucagon or intravenous glucose and/or attendance by a health professional. The hypoglycemia was not limited to patients in good or excellent metabolic control and often occurred after a single bout of exercise in patients unaccustomed to exercise or in athletic patients who were making the transition from an untrained to a trained state. Surprisingly, 12 of the patients who experienced nocturnal PEL hypoglycemia were not using significant amounts of insulin that peaked at night. Type I diabetic patients should be made aware of the possibility of PEL hypoglycemia to enable them to make adjustments in their management plans in anticipation of unusually strenuous exercise, so that they may attempt to minimize or avoid late-onset hypoglycemia.
 ...
PMID:Postexercise late-onset hypoglycemia in insulin-dependent diabetic patients. 367 76

The intrinsic processes involved in the initiation and arrest of seizures are not completely understood. Cortical and cerebellar inhibitory mechanisms, accumulation of metabolic products, and glial uptake of extracellular potassium (K+o), anions, and released neurotransmitters are all important processes that limit focal firing and terminate a seizure once it has been initiated. Of these, the intrinsic cortical inhibitory mechanisms--i.e., recurrent and surround inhibition--appear to be the most important. Active cation and anion transport processes are two metabolic events that have yet to be elucidated but clearly could be involved in terminating a seizure discharge. For example, without an active mechanism to transport chloride, opening of the chloride channel by the inhibitory transmitter GABA would not result in increased chloride permeability. The transient hypoxia and hypercapnia and lactic acidosis that follows a severe tonic-clonic seizure produces a mixed systemic metabolic and respiratory acidosis. In experimental animals, the hypercapnia that results is sufficient to block seizure discharges. Increasing the CO2 concentration significantly reduces the extension to flexion (E/F) ratio of mice given maximal electroshock seizures (MES) and increases the time required for 50% of the animals to recover sufficiently from a first MES to be able to have another MES. The decreased E/F ratio and the increased recovery time (RT50) are both indicative of a decrease in seizure activity. Since the extent to which CO2 is allowed to accumulate in the brain is regulated by the glial specific enzyme carbonic anhydrase (CA), it follows that the glial cell has an integral role in the mechanisms involved in arresting seizure activity. In contrast, hypoxia increased the E/F ratio and decreased the RT50, evidence that seizure activity was enhanced. Another metabolic factor affecting duration of seizure activity, susceptibility to seizures, and recovery from seizures is glucose. Recovery from seizures depends in part on an adequate supply of this energy source. An inverse correlation (R = 0.95) between RT50 and blood sugar was found when the blood sugar was altered experimentally by treatments that altered the endocrine status (pancreatectomy, treatment with alloxan, cortisol, insulin, glucagon, and dextrose). Since glial cells contain (as glycogen) the small amount of glucose present in the brain, they probably hasten the ability of the brain to recover normal function following a seizure.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Role of glial cation and anion transport mechanisms in etiology and arrest of seizures. 370 23

To evaluate the response during insulin-induced hypoglycemia, diabetics treated with relatively selective or nonselective beta-adrenergic blocking agents were studied. Placebo, atenolol (100 mg/day), and propranolol (80 mg b.i.d.) were administered to 12 insulin-treated diabetics for 1 week in a double-blind, randomized, crossover fashion with a 2-week washout between treatments. Sufficient intravenous insulin (0.2-0.6 units/kg) was administered to decrease plasma glucose 68% from the basal level or to less than 60 mg/dl within 90 minutes. Blood pressure changes at the nadir of plasma glucose were +15.2/-9.9 mm Hg for placebo, +27.9/0 mm Hg for atenolol, and +38.8/+14.3 mm Hg for propranolol. Diastolic blood pressure changes induced by propranolol were significantly different from those induced by atenolol (p less than 0.01) and placebo (p less than 0.01), and systolic pressure changes were significantly different (p less than 0.02) between propranolol and atenolol. Mild seizures developed in two patients treated with propranolol. Their blood pressure changes at the plasma glucose nadir were +56/+22 and +86/+31 mm Hg. Other symptoms of hypoglycemia were more frequent during beta-blocker than during placebo treatment. Differences in response may be related to the relatively selective adrenergic blocking effect of these drugs.
 ...
PMID:Hypertension in hypoglycemic diabetics treated with beta-adrenergic antagonists. 388 36

Female chicks carrying the lethal, sex-linked recessive paroxysmal (px) gene are susceptible to spontaneous and audiogenic seizures. Because seizure activity does not begin until 1 to 2 weeks posthatching - coincidental with disappearance of the yolk-sac - it is postulated that a contributing factor to seizure activity may be a developmental failure of the chick's ability to switch from lipid to carbohydrate as a primary energy source. In testing this hypothesis, three experiments were performed: 1) to evaluate cerebral energy reserves - adenosine triphosphate (ATP), phosphocreatine - of px and normal chicks; 2) to determine effects of energy source (ethanol, glucose, insulin, and glucose-insulin combined) on audiogenically-induced seizure activity and electrical seizure threshold; 3) to evaluate energy source utilization as estimated by the respiratory quotient (RQ). Brain ATP and phosphocreatine levels in px chicks were both decreased (P less than .05) as early as 10 days posthatching. Ethanol increased electrical seizure threshold in 50% of px chicks and provided protection from audiogenic stimulation. No consistent effect was found with any of the other substances. The RQ of px chicks were lower (P less than .05) than those of controls by 18 days posthatching.
 ...
PMID:Energy metabolism in audiogenically seizure-prone chicks. 388 94

Early changes in blood chemistry and the electroencephalogram were monitored during the first three hours after initiating the medium chain triglyceride (MCT) diet in nine children with intractable atypical absence seizures. Serum glucose, insulin, triglycerides, cholesterol, free fatty acids, ketone bodies concentrations, and venous pH were assayed before and at timed intervals after MCT oil was administered orally. The concentration of serum ketones rose progressively over three hours, beta-hydroxybutyrate proportionately higher than acetoacetate. A statistically significant decrease in the group mean number of epileptiform discharges occurred following MCT therapy. Seizure frequency decreased by more than 50 percent in two-thirds of the children during the 10 week treatment period.
 ...
PMID:Early biochemical and EEG correlates of the ketogenic diet in children with atypical absence epilepsy. 393 41

During a 12-month prospective study there were 125 visits to the Harlem Hospital Emergency Room for symptomatic hypoglycemia. Sixty-five patients had obtundation, stupor, or coma; 38 had confusion or bizarre behavior; 10 were dizzy or tremulous; 9 had had seizures; and 3 had suffered sudden hemiparesis. Diabetes mellitus, alcoholism, and sepsis, alone or in combination, accounted for 90% of predisposing conditions; others included fasting, terminal cancer, gastroenteritis, insulin abuse, and myxedema. Average blood glucose levels were lower among comatose than among obtunded patients, but overlap was considerable, and overall there was little correlation among cause, blood glucose levels, and symptoms. Although mortality was 11%, only one death was attributable to hypoglycemia per se, and only four survivors had focal neurological residua.
 ...
PMID:Hypoglycemia: causes, neurological manifestations, and outcome. 400 66

The mechanisms involved in the production of hypoglycemic coma were studied in rabbits. Measurements were made in brain, cerebrospinal fluid (CSF), and plasma of osmolality, Na(+), K(+), Cl(-), water content, exogenous insulin, glucose, lactate, and glutamate, while pH, Pco(2), Po(2), and bicarbonate were evaluated in arterial blood, 35 min after i.v. injection of insulin (50 U/kg), plasma glucose did not change, but brain K(+) content increased significantly. Grand mal seizures were observed in unanesthetized animals (+/-SD) 133+/-37 min after administration of insulin, at a time when brain glucose was normal, but brain tissue content of Na(+), K(+), osmoles, and water was significantly greater than normal. Coma supervened 212+/-54 min after insulin injection, at which time brain glucose, lactate, and glutamate were significantly decreased. At both 35 and 146 min after insulin administration, exogenous insulin was present in brain, but not in the CSF. After 208 min of insulin administration, animals were given i.v. glucose and sacrificed 35 min later. Most changes in the brain produced by hypoglycemia were reversed by the administration of glucose. Hypoxia (Po(2) = 23 mm Hg) was produced and maintained for 35 min in another group of animals. Hypoxia caused brain edema but did not affect brain electrolyte content. However, brain lactate concentration was significantly greater than normal. The data indicate that the seizures noted early in the course of insulin-induced hypoglycemia are temporally related to a rise in brain osmolality secondary to an increased net transport into brain of Na(+) and K(+), probably caused by insulin, per se. As hypoglycemia persists, there is also depletion of energy-supplying substrates (glucose, lactate, glutamate) in the brain, an event which coincides with the onset of coma. The brain edema observed during hypoxia is largely due to an increase in brain osmolality secondary to accumulation of lactate.
 ...
PMID:Mechanisms of seizures and coma in hypoglycemia. Evidence for a direct effect of insulin on electrolyte transport in brain. 485 37

A case of severe amitriptyline poisoning with grade IV coma, seizures, bradycardia and hypotension who did not respond to dopamine was successfully treated with prenalterol, a new cardioselective beta-agonist. The case is discussed with respect to plasma concentrations of dopamine, prenalterol and amitriptyline. Prenalterol, hydrocortisone and insulin may be useful as inotropic agents in tricyclic poisoning where dopamine fails to provide an adequate response.
 ...
PMID:Inotropic effect of prenalterol in amitriptyline poisoning. 614 67


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