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Status Epilepticus: A prolonged seizure or seizures repeated frequently enough to prevent recovery between episodes occurring over a period of 20-30 minutes. The most common subtype is generalized tonic-clonic status epilepticus, a potentially fatal condition associated with neuronal injury and respiratory and metabolic dysfunction. Nonconvulsive forms include petit mal status and complex partial status, which may manifest as behavioral disturbances. Simple partial status epilepticus consists of persistent motor, sensory, or autonomic seizures that do not impair cognition (see also EPILEPSIA PARTIALIS CONTINUA). Subclinical status epilepticus generally refers to seizures occurring in an unresponsive or comatose individual in the absence of overt signs of seizure activity. (From N Engl J Med 1998 Apr 2;338(14):970-6; Neurologia 1997 Dec;12 Suppl 6:25-30)Pilocarpine: A slowly hydrolyzed muscarinic agonist with no nicotinic effects. Pilocarpine is used as a miotic and in the treatment of glaucoma.Anticonvulsants: Drugs used to prevent SEIZURES or reduce their severity.Seizures: Clinical or subclinical disturbances of cortical function due to a sudden, abnormal, excessive, and disorganized discharge of brain cells. Clinical manifestations include abnormal motor, sensory and psychic phenomena. Recurrent seizures are usually referred to as EPILEPSY or "seizure disorder."Electroencephalography: Recording of electric currents developed in the brain by means of electrodes applied to the scalp, to the surface of the brain, or placed within the substance of the brain.Lorazepam: A benzodiazepine used as an anti-anxiety agent with few side effects. It also has hypnotic, anticonvulsant, and considerable sedative properties and has been proposed as a preanesthetic agent.Kainic Acid: (2S-(2 alpha,3 beta,4 beta))-2-Carboxy-4-(1-methylethenyl)-3-pyrrolidineacetic acid. Ascaricide obtained from the red alga Digenea simplex. It is a potent excitatory amino acid agonist at some types of excitatory amino acid receptors and has been used to discriminate among receptor types. Like many excitatory amino acid agonists it can cause neurotoxicity and has been used experimentally for that purpose.Convulsants: Substances that act in the brain stem or spinal cord to produce tonic or clonic convulsions, often by removing normal inhibitory tone. They were formerly used to stimulate respiration or as antidotes to barbiturate overdose. They are now most commonly used as experimental tools.Diazepam: A benzodiazepine with anticonvulsant, anxiolytic, sedative, muscle relaxant, and amnesic properties and a long duration of action. Its actions are mediated by enhancement of GAMMA-AMINOBUTYRIC ACID activity.Muscarinic Agonists: Drugs that bind to and activate muscarinic cholinergic receptors (RECEPTORS, MUSCARINIC). Muscarinic agonists are most commonly used when it is desirable to increase smooth muscle tone, especially in the GI tract, urinary bladder and the eye. They may also be used to reduce heart rate.Seizures, Febrile: Seizures that occur during a febrile episode. It is a common condition, affecting 2-5% of children aged 3 months to five years. An autosomal dominant pattern of inheritance has been identified in some families. The majority are simple febrile seizures (generally defined as generalized onset, single seizures with a duration of less than 30 minutes). Complex febrile seizures are characterized by focal onset, duration greater than 30 minutes, and/or more than one seizure in a 24 hour period. The likelihood of developing epilepsy (i.e., a nonfebrile seizure disorder) following simple febrile seizures is low. Complex febrile seizures are associated with a moderately increased incidence of epilepsy. (From Menkes, Textbook of Child Neurology, 5th ed, p784)Hippocampus: A curved elevation of GRAY MATTER extending the entire length of the floor of the TEMPORAL HORN of the LATERAL VENTRICLE (see also TEMPORAL LOBE). The hippocampus proper, subiculum, and DENTATE GYRUS constitute the hippocampal formation. Sometimes authors include the ENTORHINAL CORTEX in the hippocampal formation.Piracetam: A compound suggested to be both a nootropic and a neuroprotective agent.Phenytoin: An anticonvulsant that is used to treat a wide variety of seizures. It is also an anti-arrhythmic and a muscle relaxant. The mechanism of therapeutic action is not clear, although several cellular actions have been described including effects on ion channels, active transport, and general membrane stabilization. The mechanism of its muscle relaxant effect appears to involve a reduction in the sensitivity of muscle spindles to stretch. Phenytoin has been proposed for several other therapeutic uses, but its use has been limited by its many adverse effects and interactions with other drugs.Epilepsy, Tonic-Clonic: A generalized seizure disorder characterized by recurrent major motor seizures. The initial brief tonic phase is marked by trunk flexion followed by diffuse extension of the trunk and extremities. The clonic phase features rhythmic flexor contractions of the trunk and limbs, pupillary dilation, elevations of blood pressure and pulse, urinary incontinence, and tongue biting. This is followed by a profound state of depressed consciousness (post-ictal state) which gradually improves over minutes to hours. The disorder may be cryptogenic, familial, or symptomatic (caused by an identified disease process). (From Adams et al., Principles of Neurology, 6th ed, p329)Epilepsy, Temporal Lobe: A localization-related (focal) form of epilepsy characterized by recurrent seizures that arise from foci within the temporal lobe, most commonly from its mesial aspect. A wide variety of psychic phenomena may be associated, including illusions, hallucinations, dyscognitive states, and affective experiences. The majority of complex partial seizures (see EPILEPSY, COMPLEX PARTIAL) originate from the temporal lobes. Temporal lobe seizures may be classified by etiology as cryptogenic, familial, or symptomatic (i.e., related to an identified disease process or lesion). (From Adams et al., Principles of Neurology, 6th ed, p321)Epilepsy, Complex Partial: A disorder characterized by recurrent partial seizures marked by impairment of cognition. During the seizure the individual may experience a wide variety of psychic phenomenon including formed hallucinations, illusions, deja vu, intense emotional feelings, confusion, and spatial disorientation. Focal motor activity, sensory alterations and AUTOMATISM may also occur. Complex partial seizures often originate from foci in one or both temporal lobes. The etiology may be idiopathic (cryptogenic partial complex epilepsy) or occur as a secondary manifestation of a focal cortical lesion (symptomatic partial complex epilepsy). (From Adams et al., Principles of Neurology, 6th ed, pp317-8)Epilepsy: A disorder characterized by recurrent episodes of paroxysmal brain dysfunction due to a sudden, disorderly, and excessive neuronal discharge. Epilepsy classification systems are generally based upon: (1) clinical features of the seizure episodes (e.g., motor seizure), (2) etiology (e.g., post-traumatic), (3) anatomic site of seizure origin (e.g., frontal lobe seizure), (4) tendency to spread to other structures in the brain, and (5) temporal patterns (e.g., nocturnal epilepsy). (From Adams et al., Principles of Neurology, 6th ed, p313)Mossy Fibers, Hippocampal: Axons of certain cells in the DENTATE GYRUS. They project to the polymorphic layer of the dentate gyrus and to the proximal dendrites of PYRAMIDAL CELLS of the HIPPOCAMPUS. These mossy fibers should not be confused with mossy fibers that are cerebellar afferents (see NERVE FIBERS).Dentate Gyrus: GRAY MATTER situated above the GYRUS HIPPOCAMPI. It is composed of three layers. The molecular layer is continuous with the HIPPOCAMPUS in the hippocampal fissure. The granular layer consists of closely arranged spherical or oval neurons, called GRANULE CELLS, whose AXONS pass through the polymorphic layer ending on the DENDRITES of PYRAMIDAL CELLS in the hippocampus.Rats, Sprague-Dawley: A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.Epilepsies, Partial: Conditions characterized by recurrent paroxysmal neuronal discharges which arise from a focal region of the brain. Partial seizures are divided into simple and complex, depending on whether consciousness is unaltered (simple partial seizure) or disturbed (complex partial seizure). Both types may feature a wide variety of motor, sensory, and autonomic symptoms. Partial seizures may be classified by associated clinical features or anatomic location of the seizure focus. A secondary generalized seizure refers to a partial seizure that spreads to involve the brain diffusely. (From Adams et al., Principles of Neurology, 6th ed, pp317)Epilepsy, Absence: A childhood seizure disorder characterized by rhythmic electrical brain discharges of generalized onset. Clinical features include a sudden cessation of ongoing activity usually without loss of postural tone. Rhythmic blinking of the eyelids or lip smacking frequently accompanies the SEIZURES. The usual duration is 5-10 seconds, and multiple episodes may occur daily. Juvenile absence epilepsy is characterized by the juvenile onset of absence seizures and an increased incidence of myoclonus and tonic-clonic seizures. (Menkes, Textbook of Child Neurology, 5th ed, p736)Epilepsy, Generalized: Recurrent conditions characterized by epileptic seizures which arise diffusely and simultaneously from both hemispheres of the brain. Classification is generally based upon motor manifestations of the seizure (e.g., convulsive, nonconvulsive, akinetic, atonic, etc.) or etiology (e.g., idiopathic, cryptogenic, and symptomatic). (From Mayo Clin Proc, 1996 Apr;71(4):405-14)Flurothyl: A convulsant primarily used in experimental animals. It was formerly used to induce convulsions as a alternative to electroshock therapy.Neurons: The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.Paraldehyde: A hypnotic and sedative with anticonvulsant effects. However, because of the hazards associated with its administration, its tendency to react with plastic, and the risks associated with its deterioration, it has largely been superseded by other agents. It is still occasionally used to control status epilepticus resistant to conventional treatment. (From Martindale, The Extra Pharmacopoeia, 30th ed, p608-9)Disease Models, Animal: Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.Lithium Chloride: A salt of lithium that has been used experimentally as an immunomodulator.Coma: A profound state of unconsciousness associated with depressed cerebral activity from which the individual cannot be aroused. Coma generally occurs when there is dysfunction or injury involving both cerebral hemispheres or the brain stem RETICULAR FORMATION.Epilepsy, Post-Traumatic: Recurrent seizures causally related to CRANIOCEREBRAL TRAUMA. Seizure onset may be immediate but is typically delayed for several days after the injury and may not occur for up to two years. The majority of seizures have a focal onset that correlates clinically with the site of brain injury. Cerebral cortex injuries caused by a penetrating foreign object (CRANIOCEREBRAL TRAUMA, PENETRATING) are more likely than closed head injuries (HEAD INJURIES, CLOSED) to be associated with epilepsy. Concussive convulsions are nonepileptic phenomena that occur immediately after head injury and are characterized by tonic and clonic movements. (From Rev Neurol 1998 Feb;26(150):256-261; Sports Med 1998 Feb;25(2):131-6)Chlormethiazole: A sedative and anticonvulsant often used in the treatment of alcohol withdrawal. Chlormethiazole has also been proposed as a neuroprotective agent. The mechanism of its therapeutic activity is not entirely clear, but it does potentiate GAMMA-AMINOBUTYRIC ACID receptors response and it may also affect glycine receptors.Perforant Pathway: A pathway of fibers that originates in the lateral part of the ENTORHINAL CORTEX, perforates the SUBICULUM of the HIPPOCAMPUS, and runs into the stratum moleculare of the hippocampus, where these fibers synapse with others that go to the DENTATE GYRUS where the pathway terminates. It is also known as the perforating fasciculus.Phenobarbital: A barbituric acid derivative that acts as a nonselective central nervous system depressant. It potentiates GAMMA-AMINOBUTYRIC ACID action on GABA-A RECEPTORS, and modulates chloride currents through receptor channels. It also inhibits glutamate induced depolarizations.CA3 Region, Hippocampal: A subsection of the hippocampus, described by Lorente de No, that is located between the HIPPOCAMPUS CA2 FIELD and the DENTATE GYRUS.Catatonia: A neuropsychiatric disorder characterized by one or more of the following essential features: immobility, mutism, negativism (active or passive refusal to follow commands), mannerisms, stereotypies, posturing, grimacing, excitement, echolalia, echopraxia, muscular rigidity, and stupor; sometimes punctuated by sudden violent outbursts, panic, or hallucinations. This condition may be associated with psychiatric illnesses (e.g., SCHIZOPHRENIA; MOOD DISORDERS) or organic disorders (NEUROLEPTIC MALIGNANT SYNDROME; ENCEPHALITIS, etc.). (From DSM-IV, 4th ed, 1994; APA, Thesaurus of Psychological Index Terms, 1994)Epilepsia Partialis Continua: A variant of epilepsy characterized by continuous focal jerking of a body part over a period of hours, days, or even years without spreading to other body regions. Contractions may be aggravated by movement and are reduced, but not abolished during sleep. ELECTROENCEPHALOGRAPHY demonstrates epileptiform (spike and wave) discharges over the hemisphere opposite to the affected limb in most instances. The repetitive movements may originate from the CEREBRAL CORTEX or from subcortical structures (e.g., BRAIN STEM; BASAL GANGLIA). This condition is associated with Russian Spring and Summer encephalitis (see ENCEPHALITIS, TICK BORNE); Rasmussen syndrome (see ENCEPHALITIS); MULTIPLE SCLEROSIS; DIABETES MELLITUS; BRAIN NEOPLASMS; and CEREBROVASCULAR DISORDERS. (From Brain, 1996 April;119(pt2):393-407; Epilepsia 1993;34;Suppl 1:S29-S36; and Adams et al., Principles of Neurology, 6th ed, p319)Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Nipecotic AcidsExcitatory Amino Acid Agonists: Drugs that bind to and activate excitatory amino acid receptors.Landau-Kleffner Syndrome: A syndrome characterized by the onset of isolated language dysfunction in otherwise normal children (age of onset 4-7 years) and epileptiform discharges on ELECTROENCEPHALOGRAPHY. Seizures, including atypical absence (EPILEPSY, ABSENCE), complex partial (EPILEPSY, COMPLEX PARTIAL), and other types may occur. The electroencephalographic abnormalities and seizures tend to resolve by puberty. The language disorder may also resolve although some individuals are left with severe language dysfunction, including APHASIA and auditory AGNOSIA. (From Menkes, Textbook of Child Neurology, 5th ed, pp749-50; J Child Neurol 1997 Nov;12(8):489-495)Organic Chemicals: A broad class of substances containing carbon and its derivatives. Many of these chemicals will frequently contain hydrogen with or without oxygen, nitrogen, sulfur, phosphorus, and other elements. They exist in either carbon chain or carbon ring form.Stupor: A state of reduced sensibility and response to stimuli which is distinguished from COMA in that the person can be aroused by vigorous and repeated stimulation. The person is still conscious and can make voluntary movements. It can be induced by CENTRAL NERVOUS SYSTEM AGENTS. The word derives from Latin stupere and is related to stunned, stupid, dazed or LETHARGY.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Video Recording: The storing or preserving of video signals for television to be played back later via a transmitter or receiver. Recordings may be made on magnetic tape or discs (VIDEODISC RECORDING).Midazolam: A short-acting hypnotic-sedative drug with anxiolytic and amnestic properties. It is used in dentistry, cardiac surgery, endoscopic procedures, as preanesthetic medication, and as an adjunct to local anesthesia. The short duration and cardiorespiratory stability makes it useful in poor-risk, elderly, and cardiac patients. It is water-soluble at pH less than 4 and lipid-soluble at physiological pH.