Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0036572 (
seizures
)
80,221
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Epileptic syndromes are clusters of signs and symptoms regularly occurring together. These may include type of
seizure
(s), time and circumstances of occurrence, and neurological and EEG findings. Some syndromes have common signs and a predictable course (e.g., benign rolandic epilepsy). Others, such as absence
seizures
, are less specific and may include several subgroups with different outcomes and different associated features.
Still
others are rather loose collections of a few common characteristics irregularly linked together. Widely accepted syndromes in childhood include the West syndrome and Lennox-Gastaut syndromes, several myoclonic syndromes, febrile
seizures
of infancy, absence epilepsy, benign partial epilepsy, and juvenile myoclonic epilepsy. If the concept of epileptic syndromes is to be practically useful, it should be limited to clusters that are unequivocally identifiable. Heterogeneous epileptic syndromes such as West syndrome or absence epilepsies give only a limited guide to prognosis but may be important in determining investigations and treatment. A classification based on syndromes has the advantage of dispensing with most assumptions required by other systems. However, it cannot cover all the clinical aspects of epilepsy and gives no guide to the pathophysiology, genetics, and etiology of a seizure disorder. The ultimate goal remains the delineation of disease entities.
...
PMID:Epileptic syndromes in childhood. 306 14
Few prospective, population-based, long-term follow-up studies exist on people with epilepsy.
Still
fewer reports cover social outcome. Overall mortality is two to three times higher than expected. The contribution of epilepsy is variable. Importantly, the type of epilepsy syndrome and gender must be considered in the estimation of mortality rates in epilepsy. Sudden unexpected death and its mechanisms also need further consideration. Approximately. two thirds of surviving patients will be in terminal remission twenty years after onset of epilepsy and half of them are
seizure
-free without medication. The best independent predictors of remission are absence of organic brain damage, low intensity
seizure
propensity and good early effect of drug therapy. The long-term outcome is often predictable by observation of the early outcome of
seizures
. One third of children with epilepsy are mentally retarded. Poor social outcome is related to associated neurological disabilities, drug resistant
seizures
and polytherapy. However, even patients with uncomplicated epilepsy, idiopathic etiology and terminal remission without medication do less favourably than their matched controls in basic and vocational education, and reproductive activity. The employability of this subgroup, however, does not differ significantly from that of controls, compared with approximately 60% of all people with epilepsy. Further research is needed particularly to enable a better determination of predictors of long-term outcome, recurrence of
seizures
after drug withdrawal and the role of drug therapy in long-term prognosis.
...
PMID:Long-term outcome of epilepsy. 1095 38
Contrary to a century-old belief that dendritic spines are stable storage sites of long term memory, the emerging picture from a recent flurry of exciting observations using novel high resolution imaging methods of living cells in culture is that of a dynamic structure, which undergoes fast morphological changes over periods of hours and even minutes. Concurrently, the nature of stimuli which cause formation or collapse of dendritic spines has changed from a mysterious Hebbian-governed plasticity producing stimulus to the more trivial activation of the synapse by strong/weak stimulation. The molecular mechanisms underlying spine plasticity are beginning to emerge; the role of presynaptic and/or postsynaptic activity, genetic, central or local factors in the formation and retraction of spines are currently being analyzed. A common mechanism for both, formation/elongation and pruning/retraction of spines, involving changes in intracellular calcium concentration ([Ca(2+)](i)), is emerging. It appears that [Ca(2+)](i) is related to changes in spines in a bell shape form: lack of synaptic activity causes transient outgrowth of filopodia but eventual elimination of spines, a moderate rise in [Ca(2+)](i) causes elongation of existing spines and formation of new ones, while a massive increase in [Ca(2+)](i) such as that seen in
seizure
activity, causes fast shrinkage and eventual collapse of spines. Nuclear signals (e.g. CREB), activated by an increase in [Ca(2+)](i), are involved in the central regulation of spine formation, while spine shrinkage and elongation are probably triggered by local [Ca(2+)](i) changes. This hypothesis provides a parsimonious explanation for conflicting reports on activity-dependent changes in dendritic spine morphology.
Still
, the many differences between cultured neurons, with which most of current studies are conducted, and the neuron in the real brain, require a cautious extrapolation of current assumptions on the regulation of spine formation.
...
PMID:Rapid plasticity of dendritic spine: hints to possible functions? 1104 Apr 18
Brain metastases occur in 20-40% of patients with cancer and their frequency has increased over time. Lung, breast and skin (melanoma) are the commonest sources of brain metastases, and in up to 15% of patients the primary site remains unknown. After the introduction of MRI, multiple lesions have outnumbered single lesions. Contrast-enhanced MRI is the gold standard for the diagnosis. There are no pathognomonic features on CT or MRI that distinguish brain metastases from primary malignant brain tumors or nonneoplastic conditions: therefore a tissue diagnosis by biopsy should be always obtained in patients with unknown primary tumor before undergoing radiotherapy and/or chemotherapy. Some factors are prognostically important: a high Performance Status, a solitary brain metastasis, an absence of systemic metastases, a controlled primary tumor and a younger age. Based on these factors, subgroups of patients with different prognosis have been identified (RPA class I, II, III). Symptomatic therapy includes corticosteroids to reduce vasogenic cerebral edema and anticonvulsants to control
seizures
. In patients with newly diagnosed brain metastases prophylactic anticonvulsants should not be used routinely. The combination of surgery and whole-brain radiotherapy (WBRT) is superior to WBRT alone for the treatment of single brain metastasis in patients with limited or absent systemic disease and good neurological condition. Complete surgical resection allows a relief of intracranial hypertension,
seizures
and focal neurological deficits. Radiosurgery, alone or in conjunction with WBRT, yields results which are comparable to those reported after surgery followed by WBRT, provided that lesion's diameter does not exceed 3-3.5 cm. Radiosurgery offers the potential of treating patients with surgically inaccessible metastases.
Still
controversial is the need for WBRT after surgery or radiosurgery: local control seems better with the combined approach, but overall survival does not improve. Late neurotoxicity in long surviving patients after WBRT is not negligible; to avoid this complication patients with favorable prognostic factors must be treated with conventional schedules of RT, and monitoring of cognitive functions is important. WBRT alone is the treatment of choice in patients with single brain metastasis not amenable to surgery or radiosurgery, and with an active systemic disease, and in patients with multiple brain metastases. A small subgroup of these latter may benefit from surgery. The response rate of brain metastases to chemotherapy is similar to the response rate of the primary tumor and extracranial metastases, some tumor types being more chemosensitive (small cell lung carcinoma, breast carcinoma, germ cell tumors). New radiosensitizers and cytotoxic or cytostatic agents, and innovative technique of drug delivery are being investigated.
...
PMID:Management of brain metastases. 1238 50
The astute observations of Aicardi and colleagues led to the first description of Aicardi syndrome as a triad of infantile spasms, absence of the corpus callosum, and chorioretinal lacunae.
Still
diagnosed clinically, we now recognize an expanded version of this probable X-linked dominant disorder that predominantly affects females. In addition to the classic findings, patients typically experience intractable epilepsy of multiple
seizure
types, profound mental retardation, and costovertebral anomalies. Associated cerebral and ophthalmologic malformations are numerous. This article highlights several seminal citations involving the history of the initial description and the characteristic ophthalmologic and electroencephalographic features of Aicardi syndrome.
...
PMID:Aicardi syndrome. 1456 21
The goal of this study was to provide an EEG profile of patients (150) with uncontrolled (U)
seizures
, in contrast with those (150) with controlled (C) attacks. In the U group 804 EEGs were done and in the C group 674 were performed, all with both waking and sleep recordings; the range of EEG records on a given patient was 2-23. The number of spikes and the amount of abnormal slowing was quantified in each record. Two different peaks of age were evident, appearing at 10-19 yrs and 40-49 yrs. The number of patients with a spike discharge on the first EEG was 64% in the C and 92% in the U group with an increasing incidence to 83% (C) and 100% (U) in later records. If spikes were absent in the first EEG in the C group, the majority showed only rare discharges later. The spike profile of the U patient initially was that 1/2 showed a typical number of spikes and nearly 1/2 many or very many spikes. Over time a decrease was seen in those with many-very many discharges, resulting in an increase with a typical number.
Still
later, a reversal occurred in the U patients with an increasing number with many or very many spikes. The slow wave profile of the U patient was that 2/3 showed some abnormal slow waves on the first record, increasing to 100% in later records. The increase was from delta, not theta activity. The spike profile of the C patient was that a typical number of spikes was seen at first in nearly 1/2, but only a small minority showed many-very many discharges. The slow wave profile for the C patient was that theta, not delta waves, increased in time. The (median) time between a unilateral spike discharge to a bilateral discharge was 4-5 yrs, and the U group much more often than the C group showed this change to bilateral spikes. The time between unilateral to bilateral slow waves varied between 4-9 yrs.
...
PMID:The EEG profile of patients with uncontrolled vs. controlled seizures. 1516 13
Hypoxic-ischemic (H-I) injury produces extensive damage to the hippocampus of young rats. We have recently shown that administration of 125 mg kg-1 clomethiazole (CMZ), a GABA(A)-agonist, provides complete histological protection against H-I injury if administered 3 h post-H-I (Brain Res 1035 (2005) 194). However, whether that histological protection translates into lasting functional preservation is unclear. To determine whether hippocampal-based circuits remain functionally intact in CMZ-protected H-I rats, we administered 125 mg kg-1 (high dose [CMZ-HD]) or 65 mg kg-1 (low dose [CMZ-LD]) CMZ, 3 h post-H-I, and examined numerous kindling parameters in the dorsal hippocampus 60 days following H-I. Kindling parameters included afterdischarge (AD) thresholds (ADTs), AD durations and kindling rates. Additional groups assessed included vehicle-injected H-I (VIH), hypoxic, ligated and naive rats. VIH, CMZ-HD, CMZ-LD and hypoxic rats all exhibited significantly faster kindling rates than naive rats. Thus, a previous traumatic event, even hypoxia alone, facilitated subsequent
seizure
propagation.
Still
, a significantly slower kindling rate was evident in CMZ-HD rats than in hypoxic, VIH or CMZ-LD rats. Moreover, while longer pre-kindling AD durations were observed in the damaged hippocampus of VIH compared with naive rats, this was not true for either CMZ-treated groups, hypoxic or ligated rats. Collectively, these findings suggest CMZ can suppress the epileptogenic effects of H-I. Surprisingly, however, both groups of CMZ-treated rats exhibited a four to nine times greater ADT than any other group and this effect was most profound in the CMZ-protected hippocampus. Thus, CMZ administration protected local neurons against terminal insult and left network excitability relatively normal with respect to
seizure
offset mechanisms but also caused profound elevation of local ADTs, which suggests a local hypoexcitability/increased inhibition. Finally, this study demonstrates, for the first time, that the kindling model can serve as a sensitive measure of function-related neuroprotective efficacy in animal models of ischemia.
...
PMID:Neuro-overprotection? A functional evaluation of clomethiazole-induced neuroprotection following hypoxic-ischemic injury. 1574 33
Seizures
in Juvenile Myoclonic Epilepsy (JME) are dependent on the sleep-wake cycle and precipitant factors, among which sleep deprivation (SD) is one of the most important.
Still
an under diagnosed syndrome, misinterpretation of the EEGs contributes to diagnostic delay. Despite this, a quantitative EEG investigation of SD effects has not been performed. We investigated the effect of SD on EEGs in 41 patients, aged 16-50 yr. (mean 25.4), who had not yet had syndromic diagnosis after a mean delay of 8.2 yr. Two EEG recordings separated by a 48-hour interval were taken at 7 a.m. preceded by a period of 6 hours of sleep (routine EEG) and after SD (sleep-deprived EEG). The same protocol was followed and included a rest wakefulness recording, photic stimulation, hyperventilation and a post-hyperventilation period. The EEGs were analyzed as to the effect of SD on the number, duration, morphology, localization and predominance of abnormalities in the different stages. A discharge index (DI) was calculated. Out of the 41 patients, 4 presented both normal EEG recordings. In 37 (90.2%) there were epileptiform discharges (ED). The number of patients with ED ascended from 26 (70.3%) in the routine EEG to 32 (86.5%) in the sleep-deprived exam. The presence of generalized spike-wave and multispike-wave increased from 20 (54.1%) and 13 (35.1%) in the first EEG to 29 (78.4%) and 19 (51.4%) in the second, respectively (p<0.05 and p<0.01). As to localization, the number of generalized, bilateral and synchronous ED increased from 21 (56.8%) to 30 (81.1%) (p<0.01). The DI also increased; while 8 patients (21.6%) presented greater rate in the routine EEG, 25 (67.6%) did so in the sleep-deprived EEG mainly during somnolence and sleep (p<0.01). Moreover, the paroxysms were also longer in the sleep-deprived EEG. Sleep-deprived EEG is a powerful tool in JME and can contribute significantly to the syndromic characterization of this syndrome.
...
PMID:[EEG recording after sleep deprivation in a series of patients with juvenile myoclonic epilepsy]. 1605 84
With the introduction of over ten new antiepileptic drugs (AEDs) since 1993, the hope has been that at least some of these agents would be useful for not just partial
seizures
, but also for the primary generalized
seizures
of the idiopathic generalized epilepsies (IGE). The development of evidence-based treatment guidelines in the IGE, however, faces a number of challenges, particularly after an antiepileptic drug (AED) receives approval for one indication. The majority of patients with IGE are controlled with first-line therapy if appropriately selected. Case reports or series typically appear with use in refractory patients, but these studies lack the rigor to allow formulation of guidelines.
Still
we are beginning to see some good class I and II data to support use of selected second-generation AEDs. It is postulated that lamotrigine (LTG), levetiracetam (LEV), topiramate (TPM), and zonisamide (ZSM) may have efficacy for a broad spectrum of
seizure
types including those of IGE. At the present time good class I and II evidence exists to support the use of LTG for typical absence, LEV for idiopathic myoclonic
seizures
, and TPM for primary generalized tonic-clonic
seizures
, even though only TPM has FDA approval for primary generalized
seizures
. This article examines the available rigorous evidence that can support these uses and also discusses some selected other reports that suggest a spectrum of efficacy for these new agents.
...
PMID:Evidence-based treatment of idiopathic generalized epilepsies with new antiepileptic drugs. 1630 91
Cognitive and behavioral impairments are common in patients with epilepsy. Multiple factors may contribute to these difficulties; among them is antiepileptic drug (AED) treatment. We examined the short-term impact of two new add-on AEDs, pregabalin (PGB) and levetiracetam (LEV), on cognition and psychiatric states in 20 adult patients with medically refractory partial epilepsy, before and shortly after add-on titration. According to an open, prospective comparative trial, add-on PGB was titrated to 300 mg and add-on LEV to 1000 mg in 10 patients each. Patients were assessed before (T1) and 2 weeks after (T2) addition of the AED. During the trial,
seizure
frequency did not change significantly in either group. With PGB, patients manifested partly significant impairments in episodic memory of verbal and visual information. Psychiatric states were unchanged. With LEV treatment, we saw improvements in visual short-term memory performance and psychiatric states (i.e., interpersonal sensibility, depression, and anxiety). The comparison between PGB and LEV revealed a trend toward higher anxiety scores and higher variability in hostility scores with PGB that was significantly different from the trend with LEV. No significant differences were apparent in all other neuropsychological and psychiatric parameters investigated. This short-term study suggests that add-on LEV has a favorable neuropsychological and psychiatric impact. The negative neuropsychological effects of PGB may reflect temporary effects under titration.
Still
, the results did not confirm the promising effects on psychiatric comorbidity that have been emphasized by other reports.
...
PMID:Neuropsychological and psychiatric impact of add-on titration of pregabalin versus levetiracetam: a comparative short-term study. 1694 44
1
2
3
4
5
Next >>