Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
1.
Epilepsy Behav ; 151: 109623, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38262329

RESUMO

Canadian women of reproductive potential living with epilepsy present unique care challenges due to the complex interplay of hormones, seizures, and medications. This study explores reproductive health practices and counselling for women with epilepsy. Through a questionnaire developed by the Canadian League Against Epilepsy women with epilepsy (WWE) workgroup, we are the first to report demographic and real-world practice characteristics of Canadian healthcare professionals providing care for WWE with specific focus on family planning, birth plans, and postpartum care counselling. Among respondents, 76.9% routinely reviewed contraception with patients and an intrauterine device (IUD) was the most popular recommended method (85.3%). With regards to preconception planning, 50% of respondents routinely had a preconception drug level prior to pregnancy. A significant proportion, 44.9%, reported not communicating a neurology-informed birth plan to obstetrical health practitioners. The majority recommended breastfeeding for WWE on anti-seizure medications (92.3%) and regularly provided safety counselling for women in the postpartum period (84.6%). Overall, our study demonstrates that Canadian practice patterns conform reasonably well to existing evidence and guidelines, although important gaps in care exist.


Assuntos
Epilepsia , Saúde Reprodutiva , Gravidez , Humanos , Feminino , Canadá/epidemiologia , Epilepsia/tratamento farmacológico , Anticoncepção/métodos , Aconselhamento
2.
Epilepsy Behav ; 148: 109468, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37857032

RESUMO

OBJECTIVE: Approximately 150,000 Canadian women live with epilepsy, a population that presents with unique challenges. Our objective was to capture demographic and real-world practice characteristics of Canadian healthcare professionals providing care for women with epilepsy (WWE) with specific focus on reproductive considerations to identify potential gaps in knowledge and care. METHODS: A questionnaire developed by the Canadian League Against Epilepsy WWE workgroup was distributed to Canadian healthcare professionals from February 2021 to October 2022 to capture participant demographic characteristics and practice patterns in key areas of the reproductive cycle in WWE. RESULTS: A total of 156 participants completed the questionnaire, most being physicians (81.4%), epilepsy specialists (69.0%), and those who cared for adult patients (86.5%), with a significant proportion based at an academic center (65.4%). The majority of participants counselled on folic acid supplementation (89.7%). Participants selected lamotrigine and levetiracetam most frequently for either focal or generalized epilepsies during pregnancy. Additionally, 85.9% performed therapeutic drug monitoring during pregnancy. Almost all practitioners always or often counseled WWE on valproic acid on the benefits of switching to a less teratogenic medication (96.2%). Some geographic variability in practice patterns was noted with valproic acid being one of the top three medications selected for patients with generalized epilepsies in Western regions, although participants in Eastern regions had brivaracetam more commonly included as one of their top three agents for this population. SIGNIFICANCE: This is the first report of real-world Canadian practices in epilepsy care for women in pregnancy. Overall, our study reports that Canadian practice patterns conform well to current evidence and best-practice guidelines. Important variations in antiseizure medication selection across different regions were identified.


Assuntos
Epilepsia Generalizada , Epilepsia , Complicações na Gravidez , Adulto , Gravidez , Humanos , Feminino , Ácido Valproico/uso terapêutico , Canadá/epidemiologia , Epilepsia/tratamento farmacológico , Epilepsia/epidemiologia , Anticonvulsivantes/uso terapêutico , Epilepsia Generalizada/tratamento farmacológico , Complicações na Gravidez/tratamento farmacológico
3.
Epilepsia ; 58(9): 1502-1517, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28681381

RESUMO

The transition from a pediatric to adult health care system is challenging for many youths with epilepsy and their families. Recently, the Ministry of Health and Long-Term Care of the Province of Ontario, Canada, created a transition working group (TWG) to develop recommendations for the transition process for patients with epilepsy in the Province of Ontario. Herein we present an executive summary of this work. The TWG was composed of a multidisciplinary group of pediatric and adult epileptologists, psychiatrists, and family doctors from academia and from the community; neurologists from the community; nurses and social workers from pediatric and adult epilepsy programs; adolescent medicine physician specialists; a team of physicians, nurses, and social workers dedicated to patients with complex care needs; a lawyer; an occupational therapist; representatives from community epilepsy agencies; patients with epilepsy; parents of patients with epilepsy and severe intellectual disability; and project managers. Three main areas were addressed: (1) Diagnosis and Management of Seizures; 2) Mental Health and Psychosocial Needs; and 3) Financial, Community, and Legal Supports. Although there are no systematic studies on the outcomes of transition programs, the impressions of the TWG are as follows. Teenagers at risk of poor transition should be identified early. The care coordination between pediatric and adult neurologists and other specialists should begin before the actual transfer. The transition period is the ideal time to rethink the diagnosis and repeat diagnostic testing where indicated (particularly genetic testing, which now can uncover more etiologies than when patients were initially evaluated many years ago). Some screening tests should be repeated after the move to the adult system. The seven steps proposed herein may facilitate transition, thereby promoting uninterrupted and adequate care for youth with epilepsy leaving the pediatric system.


Assuntos
Epilepsia/terapia , Transição para Assistência do Adulto/normas , Adolescente , Epilepsia/diagnóstico , Necessidades e Demandas de Serviços de Saúde , Humanos , Adulto Jovem
4.
Exp Neurol ; 369: 114537, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37703949

RESUMO

OBJECTIVE: GABAA receptor subunit gene (GABR) mutations are significant causes of epilepsy, including syndromic epilepsy. This report for the first time, describes intractable epilepsy and blindness due to optic atrophy in our patient, who has a microdeletion of the GABRA1 and GABRG2 genes. We then characterized the molecular phenotypes and determined patho-mechanisms underlying the genotype-phenotype correlations in a mouse model who is haploinsufficient for both genes (Gabra1+/-/Gabrg2+/- mouse). METHODS: Electroencephalography was conducted in both human and mice with the same gene loss. GABAA receptor expression was evaluated by biochemical and imaging approaches. Optic nerve atrophy was evaluated with fundus photography in human while electronic microscopy, visual evoked potential and electroretinography recordings were conducted in mice. RESULTS: The patient has bilateral optical nerve atrophy. Mice displayed spontaneous seizures, reduced electroretinography oscillatory potential and reduced GABAA receptor α1, ß2 and γ2 subunit expression in various brain regions. Electronic microscopy showed that mice also had optic nerve degeneration, as indicated by increased G-ratio, the ratio of the inner axonal diameter to the total outer diameter, suggesting impaired myelination of axons. More importantly, we identified that phenobarbital was the most effective anticonvulsant in mice and the patient's seizures were also controlled with phenobarbital after failing multiple anti-seizure drugs. CONCLUSIONS: This study is the first report of haploinsufficiency of two GABR epilepsy genes and visual impairment due to altered axonal myelination and resultant optic nerve atrophy. The study suggests the far-reaching impact of GABR mutations and the translational significance of animal models with the same etiology.


Assuntos
Epilepsia , Receptores de GABA-A , Humanos , Camundongos , Animais , Receptores de GABA-A/genética , Potenciais Evocados Visuais , Epilepsia/genética , Modelos Animais de Doenças , Fenobarbital , Cegueira/genética , Atrofia
5.
Neurol Clin Pract ; 11(5): 385-397, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34840865

RESUMO

OBJECTIVE: To evaluate current clinical practices and evidence-based literature to establish preliminary recommendations for the management of adults using ketogenic diet therapies (KDTs). METHODS: A 12-topic survey was distributed to international experts on KDTs in adults consisting of neurologists and dietitians at medical institutions providing KDTs to adults with epilepsy and other neurologic disorders. Panel survey responses were tabulated by the authors to determine the common and disparate practices between institutions and to compare these practices in adults with KDT recommendations in children and the medical literature. Recommendations are based on a combination of clinical evidence and expert opinion regarding management of KDTs. RESULTS: Surveys were obtained from 20 medical institutions with >2,000 adult patients treated with KDTs for epilepsy or other neurologic disorders. Common side effects reported are similar to those observed in children, and recommendations for management are comparable with important distinctions, which are emphasized. Institutions differ with regard to recommended biochemical assessment, screening, monitoring, and concern for long-term side effects, and further investigation is warranted to determine the optimal clinical management. Differences also exist between screening and monitoring practices among adult and pediatric providers. CONCLUSIONS: KDTs may be safe and effective in treating adults with drug-resistant epilepsy, and there is emerging evidence supporting the use in other adult neurologic disorders and general medical conditions as well. Therefore, expert recommendations to guide optimal care are critical as well as further evidence-based investigation.

6.
J Matern Fetal Neonatal Med ; 33(16): 2841-2851, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30563399

RESUMO

Introduction: Although brainstem gliomas are a rare group of neoplasias, when they affect pregnant women, there can be challenges with diagnosis and management. This study describes a case of brainstem glioma diagnosed in pregnancy and systematically reviews the literature on brainstem gliomas in pregnancy to provide guidance for management.Material and methods: We searched five databases from inception until October 2016 using subject headings and keywords related to pregnancy and brainstem glioma, and included original research articles that described pregnancy outcomes in women with brainstem glioma. Data extraction and quality assessment using the Joanna Briggs Institute Critical Appraisal Checklist for case reports were performed in duplicate. Outcomes were reported as proportions. The study protocol was registered with the Prospero International Prospective Register of Systematic Reviews (CRD42017060196).Results: We screened 2737 titles and abstracts, and 89 full-texts. Twelve articles describing 17 pregnancies in 16 women were included in the analysis. The median gestational age at presentation was 23 weeks. All but one case presented with neurologic deficit. Magnetic resonance (MRI) imaging conclusively diagnosed all cases. Surgical tumor resection (n = 4) and radiation therapy (n = 3) were successfully undertaken during pregnancy. There were no reported sequelae of maternal oncological management on neonatal wellbeing. Maternal mortality was high (8/16, 50%) both during (n = 5) and within 4 weeks (n = 3) of pregnancy. Pregnancy losses included one pregnancy termination and four miscarriages (associated with maternal mortality). Of the 12 live-born babies, five were premature. Two of these were the result of spontaneous preterm labor and three were delivered prematurely to facilitate glioma management. There was one case of fetal growth restriction.Conclusions: Although the symptoms of brainstem gliomas often mimic those commonly encountered in pregnancy, neurologic deficits warrant urgent investigation. MRI is the diagnostic modality of choice in pregnancy. Brainstem gliomas are associated with high maternal mortality and appropriate management, including surgical tumor resection and radiation therapy, should not be delayed on account of pregnancy. Pregnancy outcomes are favorable although there is a risk of preterm birth.Key messageBrainstem gliomas are associated with high maternal mortality and timely diagnosis using magnetic resonance imaging and treatment including surgical resection and radiation therapy should not be delayed during pregnancy. Pregnancy outcomes are generally favorable except for risk of preterm birth.


Assuntos
Neoplasias do Tronco Encefálico , Glioma , Complicações Neoplásicas na Gravidez , Adulto , Neoplasias do Tronco Encefálico/diagnóstico por imagem , Neoplasias do Tronco Encefálico/mortalidade , Neoplasias do Tronco Encefálico/patologia , Neoplasias do Tronco Encefálico/terapia , Feminino , Idade Gestacional , Glioma/diagnóstico por imagem , Glioma/mortalidade , Glioma/patologia , Glioma/terapia , Humanos , Imageamento por Ressonância Magnética , Gravidez , Complicações Neoplásicas na Gravidez/diagnóstico por imagem , Complicações Neoplásicas na Gravidez/mortalidade , Complicações Neoplásicas na Gravidez/patologia , Complicações Neoplásicas na Gravidez/terapia , Resultado da Gravidez , Ultrassonografia Pré-Natal
7.
Epilepsia Open ; 5(2): 285-294, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32524054

RESUMO

OBJECTIVE: Epilepsy is one of the most common neurological disorders . Many individuals continue to have seizures despite medical and surgical treatments, suggesting adjunctive management strategies are required. Promising effects of daily listening to Mozart on reducing seizure frequency in individuals with epilepsy have been demonstrated over the last 20 years, but not in a rigorously controlled manner. In this study, we compared the effect on seizure frequency of daily listening to either Mozart K.448 or a spectrally similar, yet non-rhythmic control piece. We hypothesized that there would be no difference in seizure counts when participants listened to Mozart K.448 vs when they listened to the control piece. METHODS: We employed a randomized crossover design, in which each participant was exposed to both three months of daily listening to the first six minutes of Sonata for two pianos in D major by Mozart (Mozart K.448; treatment period) and three months of daily listening to phase-scrambled version (control period). There was a three-month baseline and a three-month follow-up period before and after the six-month listening period, respectively. Change in seizure counts obtained from the seizure diaries was considered as the main study outcome. RESULTS: Using three methodologies to investigate the existence of the treatment effect (paired t test, estimation statistics and plots, and Cohen's d), our results revealed a reduction in seizure counts during the treatment period, which was not observed for the control period (P-value < .001). SIGNIFICANCE: Using a spectrally similar control piece, our study advances previous reports that were limited by a "no music" control condition. Daily listening to Mozart K.448 was associated with reducing seizure frequency in adult individuals with epilepsy. These results suggest that daily Mozart listening may be considered as an adjunctive therapeutic option to reduce seizure burden in individuals with epilepsy.

8.
Epilepsia ; 50(4): 768-75, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19054396

RESUMO

PURPOSE: We studied the variability of the slow-spike-and-wave discharges (SSWDs) derived from AY-9944 (AY) treatment during brain development of Long-Evans hooded (LEh) rats. METHODS: Although all LEh rats received the standard dose of AY (7.5 mg/kg), we have observed an intersubject variability of the total SSWD duration at postnatal day (P) 55. Therefore, we set out to investigate the underlying brain levels of norepinephrine (NE), dopamine (DA), and serotonin (5-HT) and its metabolite (5-HIAA), as determined by high-performance liquid chromatography (HPLC) analyses from four different brain regions: thalamus (Th), frontoparietal cortex (Cx), hippocampus (Hp), and brainstem (Bs). RESULTS: All brains were obtained after two baseline electrocorticographic (ECoG) recordings with characteristic chronic, recurrent, bilaterally synchronous 4-6 Hz SSWD, at P 55 (336.25 +/- 97.23 s/h) and P60 (494.50 +/- 150.36 s) (r = 0.951, r(2) = 0.904, p < 0.005, Pearson product). The thalamic NE levels and the brainstem NE, DA, and 5HT levels were all significantly correlated with baseline SSWD duration at P55 and P60 (p < 0.01, Pearson product). CONCLUSION: Our data indicate that brain monoamine levels may determine the intersubject variability of SSWD duration in AY rats with chronic atypical absence seizures.


Assuntos
Monoaminas Biogênicas/metabolismo , Encéfalo/enzimologia , Epilepsia Tipo Ausência/patologia , Neurotransmissores/metabolismo , Animais , Animais Recém-Nascidos , Encéfalo/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Modelos Animais de Doenças , Eletroquímica/métodos , Eletroencefalografia/métodos , Epilepsia Tipo Ausência/induzido quimicamente , Epilepsia Tipo Ausência/fisiopatologia , Masculino , Ratos , Ratos Long-Evans , Dicloridrato de trans-1,4-Bis(2-clorobenzaminometil)ciclo-hexano
9.
Brain Stimul ; 12(1): 84-86, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30205951

RESUMO

BACKGROUND: Paired associative stimulation (PAS), with stimulus interval of 21.5 or 25 ms, using transcranial magnetic stimulation in the posterior-anterior (PA) current direction, produces a long-term-potentiation-like effect. Stimulation with PA directed current generates both early and late indirect (I)-waves while that in anterior-posterior (AP) current predominantly elicits late I-waves. Short interval intracortical inhibition (SICI) inhibits late I-waves but not early I-waves. OBJECTIVE: To investigate how cortical inhibition modulates the effects of PAS. METHODS: PAS at stimulus interval of 21.5 ms conditioned by SICI (SICI-PAS) was compared to PAS alone with both PA and AP directed currents. RESULTS: PAS with both current directions increased cortical excitability. SICI-PAS increased cortical excitability in the PA but not the AP current direction. CONCLUSIONS: Both early and late I-waves circuits can mediate cortical PAS plasticity under different conditions. Plasticity induction with the late but not the early I-wave circuits is blocked by SICI.


Assuntos
Potencial Evocado Motor , Potenciação de Longa Duração , Córtex Motor/fisiologia , Estimulação Magnética Transcraniana/métodos , Adulto , Excitabilidade Cortical , Feminino , Humanos , Masculino , Inibição Neural
10.
Clin Neurophysiol ; 119(6): 1328-34, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18406202

RESUMO

OBJECTIVE: Patients must remain immobile for magnetoencephalography (MEG) and MRI recordings to allow precise localization of brain function for pre-surgical functional mapping. In young children with epilepsy, this is accomplished with recordings during sleep or with anesthesia. This paper demonstrates that MEG can detect, characterize and localize somatosensory-evoked fields (SEF) in infants younger than 4 years of age with or without total intravenous anesthesia (TIVA). METHODS: We investigated the latency, amplitude, residual error (RE) and location of the N20m of the SEF in 26 infants (mean age=2.6 years). Seventeen patients underwent TIVA and 9 patients were tested while asleep, without TIVA. RESULTS: MEG detected 44 reliable SEFs (77%) in 52 median nerve stimulations. We found 27 reliable SEFs (79%) with TIVA and 13 reliable SEFs (72%) without TIVA. TIVA effects included longer latencies (p<0.001) and lower RE (p<0.05) compared to those without TIVA. Older patients and larger head circumferences also showed significantly shorter latencies (p<0.01). CONCLUSIONS: TIVA resulted in reliable SEFs with lower RE and longer latencies. SIGNIFICANCE: MEG can detect reliable SEFs in infants younger than 4 years old. When infants require TIVA for MEG and MRI acquisition, SEFs can still be reliably observed.


Assuntos
Anestesia Intravenosa/métodos , Anestesia/métodos , Mapeamento Encefálico , Epilepsia/diagnóstico , Epilepsia/fisiopatologia , Potenciais Somatossensoriais Evocados/fisiologia , Análise de Variância , Distribuição de Qui-Quadrado , Pré-Escolar , Estimulação Elétrica/métodos , Potenciais Somatossensoriais Evocados/efeitos dos fármacos , Feminino , Humanos , Lactente , Magnetoencefalografia , Masculino , Nervo Mediano/fisiopatologia , Nervo Mediano/efeitos da radiação , Tempo de Reação
11.
Ann Clin Transl Neurol ; 5(11): 1314-1322, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30480026

RESUMO

OBJECTIVE: We aimed to delineate the distribution of periventricular nodular heterotopia (PNH) in patients with 22q11.2 microdeletion syndrome (22q11.2DS) and place this in the context of other genetic forms of PNH. METHODS: We retrospectively analyzed brain imaging and postmortem data available for adult patients with 22q11.2DS. We included only those with good quality MRI data (n = 29) in addition to two patients with PNH identified through postmortem studies. We also reviewed the pattern of PNH in all genetic conditions reported with this phenotype. RESULTS: Of the total seven patients (M = 4, F = 3; age: 19-61 years) identified to have PNH, six had a history of seizures, six had schizophrenia, six had variable levels of intellectual disability, and two had obsessive compulsive disorder. In all seven patients, the nodules were located over the dorsal pole of the frontal horn of the lateral ventricles. The nodules were small, noncontiguous, and ranged in number from 1 to 10 per individual. Our review identified 37 genetic conditions associated with PNH. With the cases reported here, 22q11.2DS becomes the fifth most commonly reported genetic condition, and the third most common copy number variation, associated with PNH. INTERPRETATION: The neuropsychiatric manifestations in our patients with PNH support other data indicating abnormal neurodevelopment as part of the pathogenesis of 22q11.2DS.The location and cellular characteristics of PNH in 22q11.2DS overlaps with a group of migrating postnatal interneurons termed Arc cells, although more research is needed to confirm that PNH in 22q11.2DS represents Arc cells arrested in their migratory pathway.

12.
Neurosci Lett ; 418(1): 13-7, 2007 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-17350760

RESUMO

We investigated the role of 5-HT(2A) and 5-HT(2C) receptors in atypical absence seizures (AAS) induced by trans-1,4-bis[2-chloro-benzylaminomethyl] cyclohexane, dihydrocholoride (AY-9944). The total duration and number and mean duration of the spontaneous bursts of slow spike-and-wave discharges (SSWD) that characterize the AY model were measured using electrocorticographic (ECoG) recordings in freely moving animals. In a randomized counterbalanced dose response design, rats were treated with either the 5-HT(2A) agonist 1-[2,5-dimethoxy-4-iodophenyl]-2-aminopropane (DOI, 0.5, 1 or 2 mg/kg), the 5-HT(2C) preferring agonist m-chlorophenylpiperazine (mCPP, 1, 2, or 4 mg/kg), the 5-HT(2A) antagonist ketanserin (2.5 or 5 mg/kg), or vehicle. DOI significantly reduced the total duration and number of SSWD. In contrast, mCPP had no effect on total duration or number of SSWD. Ketanserin exacerbated the number of SSWD at 2.5 mg/kg but produced mixed results at 5.0 mg/kg. However, none of the treatments affected the mean SSWD duration. These data support the hypothesis that 5HT(2A) receptors are involved in the pathology of experimental atypical absence seizures.


Assuntos
Anticolesterolemiantes/toxicidade , Epilepsia Tipo Ausência/induzido quimicamente , Epilepsia Tipo Ausência/metabolismo , Receptores 5-HT2 de Serotonina/metabolismo , Dicloridrato de trans-1,4-Bis(2-clorobenzaminometil)ciclo-hexano/toxicidade , Anfetaminas/farmacologia , Animais , Ketanserina/farmacologia , Piperazinas/farmacologia , Ratos , Receptores 5-HT2 de Serotonina/efeitos dos fármacos , Antagonistas da Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia
13.
Epilepsy Res Treat ; 2012: 103160, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22953057

RESUMO

Complex partial seizures (CPSs) can present with various semiologies, while mesial temporal lobe epilepsy (mTLE) is a well-recognized cause of CPS, neocortical temporal lobe epilepsy (nTLE) albeit being less common is increasingly recognized as separate disease entity. Differentiating the two remains a challenge for epileptologists as many symptoms overlap due to reciprocal connections between the neocortical and the mesial temporal regions. Various studies have attempted to correctly localize the seizure focus in nTLE as patients with this disorder may benefit from surgery. While earlier work predicted poor outcomes in this population, recent work challenges those ideas yielding good outcomes in part due to better localization using improved anatomical and functional techniques. This paper provides a comprehensive review of the diagnostic workup, particularly the application of recent advances in electroencephalography and functional brain imaging, in neocortical temporal lobe epilepsy.

14.
Seizure ; 21(6): 412-6, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22537415

RESUMO

Circadian rhythm of seizure is underestimated in the study of focal epilepsies. A review of the current literature revealed a clear correlation between cortical epileptogenic focus and the circadian phase of seizure peak occurrence in adult patients. A single diurnal peak at 19:00 was found in seizures originating from the occipital lobe, between 5:00 and 7:00 in frontal lobe seizures, and between 16:00 and 17:00 h in temporal lobe seizures. Two diurnal peaks, between 5:00 and 7:00, and at 23:00 are reported in seizures from the parietal lobe, and between 7:00 to 8:00 and 16:00 to 17:00 in mesial temporal onset seizures. This circadian character of seizure occurrence in focal epilepsies may not be unique to partial seizures since recent clinical and experimental data indicate that generalized seizures also demonstrate circadian effects. The clinical evidence on generalized seizures and epilepsies is not recent, but a formal integration of circadian rhythmicity in our understanding and clinical management of epilepsies may be warranted.


Assuntos
Ritmo Circadiano/fisiologia , Epilepsias Parciais/fisiopatologia , Convulsões/fisiopatologia , Animais , Humanos
15.
Healthc Policy ; 4(2): 59-68, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19377370

RESUMO

BACKGROUND: Long waits for publicly funded magnetic resonance imaging (MRI) services have spurred the opening of private MRI centres in Canada. Little is known about the number and utilization of these facilities. METHODS: The authors surveyed all 17 private and 69 of 73 public English-speaking MRI centres in Canada in 2006, using hours of operation and waits for an elective MRI as surrogate measures of procedure volume and facility capacity. RESULTS: Public MRIs had more hours of operation on weekdays (14.7 vs. 9.7, p<0.001) and weekends (11.8 vs. 8.2, p<0.001). Waits were longer in public vs. private MRI centres (13.6 vs. 0.5 weeks, p<0.001). CONCLUSIONS: Private MRIs provided fewer hours of operation but shorter wait times compared to public centres. This finding suggests that private centres have unused capacity and relatively small procedure volumes, and provide a minority of studies.

16.
Epilepsia ; 47(2): 240-6, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16499747

RESUMO

PURPOSE: To test the hypothesis that serotonin (5-HT) plays a role in the modulation of experimental atypical absence seizures. METHODS: Male Long-Evans hooded rats were treated from postnatal day (P) 2 to P20 with the cholesterol inhibitor AY-9944 (AY). Epidural electrodes were implanted for electrocorticography (ECoG) followed by serotonin depletion by using para-cholorophenylalanine (PCPA). High-performance liquid chromatography (HPLC) was used to measure the levels of serotonin and its metabolite (5-HIAA) in various brain regions. Serotonin metabolism was computed by using the 5-HIAA/5-HT ratio and used to ascertain differences between groups. RESULTS: PCPA treatment was associated with a significant decrease in the total slow spike-and-wave discharge (SSWD) duration in AY-treated rats compared with controls (p < 0.01). HPLC data confirmed the PCPA depletion of 5-HT and 5-HIAA in cortex, thalamus, hippocampus, and brainstem compared with naïve rats. AY-treated rats showed higher levels of 5-HIAA and 5-HT in the same brain regions, with a concomitant decrease in rates of serotonin turnover. CONCLUSIONS: The data indicate that serotonin depletion protects against experimental atypical absence seizures. The increased levels of 5-HIAA and 5-HT and altered rates of serotonin turnover suggest that the serotonergic neurotransmission may be perturbed in the AY rat.


Assuntos
Anticolesterolemiantes , Encéfalo/metabolismo , Epilepsia Tipo Ausência/induzido quimicamente , Epilepsia Tipo Ausência/fisiopatologia , Serotonina/fisiologia , Dicloridrato de trans-1,4-Bis(2-clorobenzaminometil)ciclo-hexano , Animais , Encéfalo/efeitos dos fármacos , Química Encefálica/efeitos dos fármacos , Química Encefálica/fisiologia , Cromatografia Líquida de Alta Pressão , Eletroencefalografia/efeitos dos fármacos , Eletroencefalografia/estatística & dados numéricos , Epilepsia Tipo Ausência/metabolismo , Fenclonina/farmacologia , Ácido Hidroxi-Indolacético/metabolismo , Masculino , Ratos , Ratos Long-Evans , Serotonina/deficiência , Serotonina/metabolismo , Antagonistas da Serotonina/farmacologia , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
17.
Epilepsy Behav ; 9(4): 564-72, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17030024

RESUMO

We studied daily rhythms of chronic seizure activity and behavior in adult rats and mice treated with the cholesterol biosynthesis inhibitor AY-9944 (AY) during early postnatal development. Chronic atypical absence seizures were verified in the AY-treated animals by the presence of spontaneous 5- to 6-Hz slow spike-wave discharges (SSWDs) in the neocortex. General behavioral activity, as measured by total movements (TM), movement time (MT), ambulatory movement time (AMT), time spent in center of arena (CT), jumps (JFP), and rotational behavior (TURNS), were continuously recorded under a 12-hour light:12-hour dark photocycle. The average SSWD duration in AY-treated rats varied daily, with two peaks occurring at approximately dark phase and light phase onset. Mice treated with AY exhibited significant increases in all behavioral measures during the light and dark phases, with the exception of light-phase CT, which did not differ from that of controls. Consequently, the daily rhythm of total behavioral activity (TM) exhibited a significantly higher mean oscillation (mesor) and amplitude without evidence of phase shift compared with the TM rhythm of controls. The occurrence of SSWD activity in the AY model appears to be subject to regulation by biological timing mechanisms and, furthermore, associated with motor hyperactivity that does not alter the timing of behavioral rhythmicity.


Assuntos
Comportamento Animal , Ritmo Circadiano , Epilepsia Tipo Ausência/fisiopatologia , Movimento , Convulsões/fisiopatologia , Animais , Anticolesterolemiantes , Córtex Cerebral/fisiopatologia , Modelos Animais de Doenças , Eletroencefalografia , Epilepsia Tipo Ausência/diagnóstico , Masculino , Camundongos , Camundongos Endogâmicos C3H , Ratos , Ratos Long-Evans , Convulsões/induzido quimicamente , Dicloridrato de trans-1,4-Bis(2-clorobenzaminometil)ciclo-hexano
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA