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- ItemSomente MetadadadosAlterations of the neocortical GABAergic system in the pilocarpine model of temporal lobe epilepsy: Neuronal damage and immunocytochemical changes in chronic epileptic rats(Elsevier B.V., 2002-08-15) Silva, A. V.; Sanabria, ERG; Cavalheiro, E. A.; Spreafico, R.; Universidade Federal de São Paulo (UNIFESP); Ist Nazl Neurol C BestaA wealth of previous studies reported pathological alterations in extrahippocampal regions in mesial temporal lobe epilepsy. Previous experimental findings have also demonstrated that the entorhinal cortex and the neocortex are damaged in different animal models of acute limbic seizures. the present study was aimed at verifying possible alterations in neocortical areas, and, in particular, structural changes of GABAergic interneurons in the sensorimotor cortex, in pilocarpine-induced chronic epilepsy in the rat. Series of sections were Nissl stained and processed for immunocytochemistry using antibodies that recognize nonphosphorylated neurofilament (SMI311), glial fibrillary acidic protein (GFAP), the calcium-binding protein parvalbumin (PV) which is expressed by a subset of cortical GABAergic neurons, the GABA transporter (GAT1), and isoform 65 of glutamic acid decarboxylase (GAD65), the GABA synthetic enzyme. Epileptic rats showed decreased cortical thickness, and diffuse gliosis was observed with GFAP antibody. Neurofilament alterations were also detected in sections processed using SMI311 antiserum. in addition, a diffuse decrease of PV, GAD65, and GAT1 immunoreactivity was observed in the sensorimotor cortex. Altered expression of PV, GAD65, and GAT1 pointed out specific neocortical disturbances in GABAergic inhibition, which could play a crucial role in seizure generation and expression. Thus, the present findings indicate that damage of GABAergic interneurons could be strictly associated with neocortical hyperexcitability in temporal lobe epilepsy. (C) 2002 Elsevier Science Inc. All rights reserved.
- ItemSomente MetadadadosAmino acid and monoamine alterations in the cerebral cortex and hippocampus of mice submitted to ricinine-induced seizures(Elsevier B.V., 2002-07-01) Ferraz, A. C.; Anselmo-Franci, J. A.; Perosa, SR; Castro-Neto, E. F. de; Bellissimo, M. I.; Oliveira, B. H. de; Cavalheiro, E. A.; Naffah-Mazzacoratti, MDG; Da Cunha, C.; Univ Fed Parana; Fac Odontol; Universidade Federal de São Paulo (UNIFESP)The alkaloid ricinine isolated from the plant Ricinus communis, when administered to mice at high doses, induces clonic seizures accompanied by electroencephalographic alterations in the cerebral cortex and hippocampus. the lethal nature of ricinine-induced seizures is considered to be a good model for the study of the events that cause death during clonic seizures, particularly those related to respiratory spasms. the initial signs (pre-seizure period) were marked by exophthalmus and decreased locomotor behavior. Animals killed during the preseizure period presented an increased utilization rate (HVA/DA) of dopamine (DA), an increased concentration of noradrenaline (NA), and a decreased concentration of glutamate (Glu), glutamine (Gln), taurine (Tau), and serotonin (5-HT) in the cerebral cortex. the seizure period is characterized by the occurrence of hind limb myoclonus and respiratory spasms, which are followed by death. Alterations in the cerebral cortex concentration of these neurotransmitters persisted during the seizure period. These alterations are only partially observed in the hippocampus, mainly during the seizure period. the present results suggest that an increased release of Glu in the cerebral cortex can be implicated in the genesis of the ricinine-induced seizure and that it triggers many anticonvulsive mechanisms, like the release of Tau, DA, 5-HT, and NA. (C) 2002 Elsevier Science Inc. All rights reserved.
- ItemSomente MetadadadosBehavioral effects of a neurotoxic compound isolated from Clibadium surinamense L (Asteraceae)(Elsevier B.V., 2006-05-01) Costa, Elson Alves [UNIFESP]; Rocha, F. F.; Torres, MLB; Souccar, C.; De Lima, TCM; Lapa, A. J.; Lima-Landman, MTR; Universidade Federal de São Paulo (UNIFESP); Universidade Federal de Santa Catarina (UFSC); Universidade Federal de Goiás (UFG); Ctr Univ Barra MansaClibadium surinamense L, popularly known as cunambi, is a native plant from the Northern region of Brazil illegally used for predatory fishing. Previous results from our laboratory have demonstrated that the oral treatment of mice with the ethanolic extract (EE) of the leaves of the plant induced generalized tonic-clonic seizures followed by death within 30 min. the aims of the present paper were to characterize the convulsant effect of the hexanic extract (HE) of the stems and leaves of C surinamense and, by bioguided purification, to identify the active principle and its mechanism of action. the leaves and stems were extracted with hexane (100 g/L) in Soxhlet for 36h (yield of 2.4%), the solvent was evaporated and the powder dissolved in 1.5% saline/Tween 80. Male mice (30-35g) treated with HE (22.5-360 mg/kg, p.o.) showed behavioral alterations consistent with CNS stimulation. the intensity and duration of the effect were proportional to the administered doses. the behavioral alterations, measured with a graded score of seizure severity, revealed that pretreatment with carbamazepine (30 mg/kg, i.p., 60 min) or phenytoin (50 mg/kg, i.p., 30 min) did not alter the HE convulsive effect. in contrast, phenobarbital (30 mg/kg, i.p., 60 min) or diazepam (2 mg/kg, i.p., 30 min) reduced the HE effect, increasing the ED50 for clonic seizures from 64.4 to 89.8 mg/kg and 168.9 mg/kg, respectively. Purification of the HE in a silica gel column eluted with a hexane/ethyl acetate gradient yielded a single fraction with convulsant effect in which cunaniol acetate was identified by H-1 NMR as the main active compound. These results indicated that inhibition of GABAergic transmission by cunaniol acetate might be responsible for the convulsant effects of C. surinamense L in mice, but do not exclude a direct cunaniol action labilizing neuronal excitability. (c) 2006 Elsevier Inc. All rights reserved.
- ItemAcesso aberto (Open Access)Complex partial seizures and aphasia as initial manifestations of non-ketotic hyperglycemia: case report(Academia Brasileira de Neurologia - ABNEURO, 1998-06-01) Batista, Marcus Sabry Azar [UNIFESP]; Silva, DÉlrio FaÇanha [UNIFESP]; Ferraz, Henrique Ballalai [UNIFESP]; Andrade, Luiz Augusto Franco de [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)We describe a case of non-ketotic hyperglycemia (NKH), heralded by complex partial seizures and aphasia of epileptic origin, besides versive and partial motor seizures. This clinical picture was accompanied by left fronto-temporal spikes in the EEG. The seizures were controlled by carbamazepine only after the control of the diabetes. A month later, carbamazepine was discontinued. The patient remained without seizures, with normal language, using only glybenclamide. Complex partial seizures, opposed to simple partial seizures, are rarely described in association to NKH. Epileptic activity localized over language regions can manifest as aphasia.
- ItemAcesso aberto (Open Access)Epilepsy kills(Academia Brasileira de Neurologia - ABNEURO, 2012-03-01) Scorza, Fulvio Alexandre [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)People with epilepsy are more likely to die prematurely, and the most common epilepsy-related category of death is sudden unexpected death in epilepsy (SUDEP). Thus, the purpose of this article was to alert the scientific community about SUDEP.
- ItemSomente MetadadadosLithium-methomyl induced seizures in rats: A new model of status epilepticus?(Elsevier B.V., 2007-03-01) Kaminski, Rafal M.; Blaszczak, Piotr; Dekundy, Andrzej; Parada-Turska, Jolanta; Calderazzo, Lineu; Cavalheiro, Esper A.; Turski, Waldemar A.; Inst Agr Med; Med Univ; Universidade Federal de São Paulo (UNIFESP)Behavioral, electroencephalographic (EEG) and neuropathological effects of methomyl, a carbamate insecticide reversibly inhibiting acetylcholinesterase activity, were studied in naive or lithium chloride (24 h, 3 mEq/kg, s.c.) pretreated male Wistar rats. in naive animals, methomyl with equal potency produced motor limbic seizures and fatal status epilepticus. Thus, the CD50 values (50% convulsant dose) for these seizure endpoints were almost equal to the LD50 (50% lethal dose) of methomyl (13 mg/kg). Lithium pretreated rats were much more susceptible to convulsant, but not lethal effect of methomyl. CD50 values of methomyl for motor limbic seizures and status epilepticus were reduced by lithium pretreatment to 3.7 mg/kg (a 3.5-fold decrease) and 5.2 mg/kg (a 2.5-fold decrease), respectively. in contrast, lithium pretreatment resulted in only 1.3-fold decrease of LD50 value of methomyl (9.9 mg/kg). Moreover, lithium-methomyl treated animals developed a long-lasting status epilepticus, which was not associated with imminent lethality observed in methomyl-only treated rats. Scopolamine (10 mg/kg) or diazepam (10 mg/kg) protected all lithium-methomyl treated rats from convulsions and lethality. Cortical and hippocampal EEG recordings revealed typical epileptic discharges that were consistent with behavioral seizures observed in lithium-methomyl treated rats. in addition, convulsions induced by lithium-methomyl treatment were associated with widespread neurodegeneration of limbic structures. Our observations indicate that lithium pretreatment results in separation between convulsant and lethal effects of methomyl in rats. As such, seizures induced by lithium-methomyl administration may be an alternative to lithium-pilocarpine model of status epilepticus, which is associated with high lethality. (c) 2006 Elsevier Inc. All rights reserved.
- ItemAcesso aberto (Open Access)Neuropsychiatric Lupus in clinical practice(Assoc Arquivos Neuro- Psiquiatria, 2016) Alessi, Helena [UNIFESP]; Dutra, Livia Almeida [UNIFESP]; Braga-Neto, Pedro; Pedroso, Jose Luiz [UNIFESP]; Toso, Fabio Fieni [UNIFESP]; Kayser, Cristiane [UNIFESP]; Barsottini, Orlando Graziani Povoas [UNIFESP]Systemic lupus erythematosus (SLE) is a chronic autoimmune disease involving multiple organs, characterized by the production of autoantibodies and the development of tissue injury. The etiology of SLE is partially known, involving multiple genetic and environmental factors. As many as 50% of patients with SLE have neurological involvement during the course of their disease. Neurological manifestations are associated with impaired quality of life, and high morbidity and mortality rates. Nineteen neuropsychiatric syndromes have been identified associated with SLE, and can be divided into central and peripheral manifestations. This article reviews major neuropsychiatric manifestations in patients with SLE and discusses their clinical features, radiological findings and treatment options.
- ItemSomente MetadadadosPro-epileptic effect of alfentanil in rats subjected to pilocarpine-induced chronic epilepsy(Elsevier B.V., 2006-05-15) Garrido Sanabria, Emilio Rafael; D'Andrea Vieira, Isabella; Fernanda Da Silveira Pereira, Maria; Coutinho Faria, Leonardo; Da Silva, Andre Cesar; Abrao Cavalheiro, Esper; Silva Fernandes, Maria Jose da; Universidade Federal de São Paulo (UNIFESP); Univ BrownsvillePharmacological induction of epileptiform activity is a complementary method to study the epileptogenic area in drug-resistant epileptic patients. Among the different activation methods, fentanyl derivatives (e.g. alfentanil) provide one of the most efficient tools in triggering epileptiform abnormalities in surgical candidates. in this study, we tested the pro-epileptic effect of different concentrations of alfentanil in hippocampal slices obtained from control and pilocarpine-treated chronic epileptic rats. the pro-convulsant action of alfentanil was also studied in control and pilocarpine-treated epileptic rats implanted with subdural and hippocampal electrodes for electroencephalographic recordings. in 90% of slices from control animals, application of affentanil (0.1-5 mu M) induced a significant enhancement in amplitude and number of population spikes recorded in the hippocampal CA1 region. in contrast, alfentanil produced a significant reduction in the amplitude of population spikes in slices from pilocarpine-treated epileptic rats. These changes were accompanied by a significant increase in the number of population spikes in the form of epileptiform multispike responses of epileptic slices. Naloxone (20 mu M) antagonized the effect of alfentanil in both control and epileptic slices, reducing the number of population spikes in slices from epileptic rats. in control rats, alfentanil induced epileptiform abnormalities in the hippocampal and cortical electroencephalographic recordings but only at concentrations higher than 200 [mu g/kg (e.g. 350 mu g/kg). Lower doses of affentanil (25 mu g/kg) elicited epileptiform abnormalities only in chronic epileptic rats. the potent action of a minimal dose of alfentanil in inducing epileptiform activity suggests an enhancement of the pro-convulsant action of mu-receptor opioids in chronic temporal lobe epilepsy. (c) 2006 Elsevier Inc. All rights reserved.
- ItemAcesso aberto (Open Access)The promise of omega-3 against sudden unexpected death in epilepsy: until further notice, it remains innocent, until proven guilty(Academia Brasileira de Neurologia - ABNEURO, 2013-01-01) Scorza, Fulvio Alexandre [UNIFESP]; Lopes, Antonio Carlos [UNIFESP]; Cysneiros, Roberta Monterazzo [UNIFESP]; Arida, Ricardo Mario [UNIFESP]; Silva, Maurício Rocha E; Universidade Federal de São Paulo (UNIFESP); Universidade Presbiteriana Mackenzie Programa de Pós-graduação em Distúrbios do Desenvolvimento; Universidade de São Paulo (USP)The present paper highlighted the importance of the recommended levels of fish consumption or omega-3 supplementation in order to minimize the frequency of seizures in people with uncontrolled epilepsy and, especially, to reduce the occurrence of sudden unexpected death in epilepsy (SUDEP).
- ItemSomente MetadadadosRicinine-elicited seizures: A novel chemical model of convulsive seizures(Elsevier B.V., 2000-04-01) Ferraz, A. C.; Pereira, L. F.; Ribeiro, R. L.; Wolfman, C.; Medina, J. H.; Scorza, F. A.; Santos, N. F.; Cavalheiro, E. A.; Da Cunha, C.; Univ Fed Parana; Univ Buenos Aires; Universidade Federal de São Paulo (UNIFESP)The present investigation introduces ricinine-elicited seizures as a novel chemical model of convulsive seizure. Ricinine, a neutral alkaloid obtained from the plant Ricinus communis, induces seizures when administered to mice at doses higher than 20 mg/kg. Animals presenting sei zures showed a marked preconvulsive phase followed by short duration hind limb myoclonus: respiratory spasms, and death. the lethal nature of ricinine seizures is also pointed out as a good model to study the events causing death in clonic seizures, particularly those related to respiratory spasms, which are also observed in some types of human epilepsy. the behavioral signs of ricinine-elicited seizures are accompanied by electrographic alterations more evident during the preconvulsive phase in the cerebral cortex and more intense during the ictal phase both in the cortex and in the hippocampus. the ricinine-elicited seizures may be inhibited by diazepam but not by phenobarbital, phenytoin, or ethosuximide. Micromolar concentrations of ricinine cause a small decrease in the binding of [H-3]-flunitrazepam to cerebral cortex membranes, but do not alter the binding of other radioligands to AMPA, 5-HT1A, muscarinic, and alpha(1)-adrenergic receptors. Although ricinine presents a cyanide radical, only higher doses of ricinine (4 mM) caused a small impairment of mitochondrial respiration. These results suggest that the mechanism of action of ricinine probably involves the benzodiazepine site in the GABA, receptor. This may represent a new mechanism of drug-elicited seizures that may contribute to a better understanding of epilepsy and to new therapeutic approaches to this disease. (C) 2000 Elsevier Science Inc.
- ItemAcesso aberto (Open Access)Role of adenosine in the antiepileptic effects of deep brain stimulation(Frontiers Research Foundation, 2014-10-02) Miranda, Maisa F.; Hamani, Clement [UNIFESP]; Almeida, Antonio-Carlos G. de; Amorim, Beatriz Oliveira [UNIFESP]; Macedo, Carlos Eduardo [UNIFESP]; Fernandes, Maria Jose da Silva [UNIFESP]; Nobrega, Jose N.; Aarão, Mayra Consuelo; Madureira, Ana Paula; Rodrigues, Antonio M.; Andersen, Monica Levy [UNIFESP]; Tufik, Sergio [UNIFESP]; Mello, Luiz Eugenio Araujo de Moraes; Covolan, Luciene [UNIFESP]; Univ Fed Sao Joao del Rei; Universidade Federal de São Paulo (UNIFESP); Ctr Addict & Mental Hlth; Univ TorontoDespite the effectiveness of anterior thalamic nucleus (AN) deep brain stimulation (DBS) for the treatment of epilepsy, mechanisms responsible for the antiepileptic effects of this therapy remain elusive. As adenosine modulates neuronal excitability and seizure activity in animal models, we hypothesized that this nucleoside could be one of the substrates involved in the effects of AN DBS. We applied 5 days of stimulation to rats rendered chronically epileptic by pilocarpine injections and recorded epileptiforrn activity in hippocampal slices. We found that slices from animals given DBS had reduced hippocampal excitability and were less susceptible to develop ictal activity. in live animals, AN DBS significantly increased adenosine levels in the hippocampus as measured by microdialysis. the reduced excitability of DBS in vitro was completely abolished in animals pre-treated with A1 receptor antagonists and was strongly potentiated by A1 receptor agonists. We conclude that some of the antiepileptic effects of DBS may be mediated by adenosine.
- ItemAcesso aberto (Open Access)Seizure occurrence in patients with chronic renal insufficiency in regular hemodialysis program(Academia Brasileira de Neurologia - ABNEURO, 2005-09-01) Scorza, Fulvio Alexandre [UNIFESP]; Albuquerque, Marly de [UNIFESP]; Arida, Ricardo Mario [UNIFESP]; Cysneiros, Roberta Monterazzo [UNIFESP]; Henriques, Tânia Maria Guedes; Scorza, Carla Alessandra [UNIFESP]; Cruz, Jener; Kesrouani, Silvana; Gomes, Rui Alberto; Cavalheiro, Esper Abrão [UNIFESP]; Universidade de Mogi das Cruzes Núcleo de Pesquisas Tecnológicas Laboratório de Neurociências; Universidade Federal de São Paulo (UNIFESP); Instituto de Nefrologia de Mogi das CruzesHemodialysis-associated seizure is a complication of hemodialysis. This report describes the occurrence of seizures in patients with end stage renal disease on dialysis therapy at the Nephrology Institute of Mogi das Cruzes, São Paulo State, Brazil. A retrospective medical history of 189 patients was reviewed to investigate the occurrence of convulsive seizures during dialytic program. Seven patients with history of seizures were selected but five of them were included in our study. Three patients presented generalized tonic-clonic seizures, one had partial seizure with secondary generalization, and one presented unclassified seizure. Three patients presented seizure just during the dialysis (unique seizure) and one of them presented convulsive status epilepticus. The two other patients had already presented seizures prior the beginning of dialysis. We conclude that seizures in renal failure could be considered as occasional events that do not usually become chronic.
- ItemAcesso aberto (Open Access)Sudden death in a child with epilepsy: potential cerebellar mechanisms?(Academia Brasileira de Neurologia - ABNEURO, 2011-08-01) Scorza, Fulvio Alexandre [UNIFESP]; Terra, Vera Cristina; Arida, Ricardo Mario [UNIFESP]; Sakamoto, Américo Ceiki [UNIFESP]; Harper, Ronald M.; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP); University of California at Los Angeles David Geffen School of Medicine Department of NeurobiologyEpilepsy is the most common neurological disorder in humans. People with epilepsy are more likely to die prematurely than those without epilepsy, with the most common epilepsy-related category of death being sudden unexpected death in epilepsy (SUDEP). The central mechanisms underlying the fatal process remain unclear, but cardiac and respiratory mechanisms appear to be involved. Recently, cerebellar, thalamic, basal ganglia and limbic brain structures have been shown to be implicated in respiratory and cardiac rate regulation. We discuss here the potential mechanisms underlying the fatal process, with a description of cerebellar actions likely failing in that SUDEP process.
- ItemSomente MetadadadosSurgical Treatment Alone of Cerebral Aspergillosis in Immunocompetent Patient(Thieme Medical Publ Inc, 2016) Beraldo, Daniel [UNIFESP]; Guerra, Ramon; Alvarenga, Vinicius; Crepaldi, LeticiaAspergillosis is a disease that predominantly affects immunocompromised patients. The incidence in immunocompetents is rare, and manifestation is generally pulmonary. Few reports in the literature refer to isolated cerebral aspergillosis in individuals with no chronic comorbidities. We describe a case of a 59-year-old rural worker without previous pathologies who had a partial convulsive crisis in a subtle form, with self-limiting and non recurrent secondary generalization. Diagnostic investigation demonstrated a sub cortical tumorlike lesion in the right precentral gyrus by nuclear magnetic resonance that allowed en bloc microsurgical resection, with histopathologic findings indicating cerebral aspergillosis. Because of the delay in obtaining the result of the biopsy due to technical difficulties with analysis, the diagnosis was delayed. The patient was clinically stable, with imaging without modifications and with negative serologic tests, so it was decided to follow the patient without antifungal therapy, which was successful. This was a case of isolated cerebral aspergillosis in an immunocompetent individual who was successfully treated by complete resection of the lesion alone, without combined antifungal therapy.
- ItemSomente MetadadadosVesicular acetylcholine transporter knock-down mice are more susceptible to pilocarpine induced status epilepticus(Elsevier B.V., 2008-05-09) Guidine, Patricia A. M.; Rezende, Gustavo H. S.; Queiroz, Claudio M. [UNIFESP]; Mello, Luiz Eugenio [UNIFESP]; Prado, Vania F.; Prado, Marco A. M.; Pereira, Grace S.; Moraes, Marcio F. D.; Universidade Federal de Minas Gerais (UFMG); Universidade Federal de São Paulo (UNIFESP)The pilocarpine (PILO) animal model of Temporal Lobe Epilepsy (TLE) portrays the most common changes in hippocampal circuitry found in human TLE. the acute cholinergic insult induces status epilepticus (SE), which triggers an overwhelming set of plastic events that result on late spontaneous recurrent limbic seizures. It has been suggested that the cholinergic system plays an important role in the synchronization required for ictogenesis. We took advantage of a knock-down animal model for the vesicular acetylcholine transporter (VAChT KD) to investigate seizure genesis in a model of cholinergic dysfunction. We induced SE in VAChT KD and wild-type (WT) mice by a single intraperitoneal injection of PILO in order to evaluate susceptibility to seizures. Video-EEG recordings evaluated epileptiform activity and ictal behavior onset. the hypothesis tested is that innate cholinergic hypofunction could result in increased susceptibility to PILO. VAChT KDHOM mice showed shorter latency for the first epileptiform discharge and for the first seizure episode, when compared to other groups. the duration of these seizure episodes, however, were not statistically different among experimental groups. On the other hand, VAChT KDHOM had the shortest latency to isoelectric EEG, when compared to WT and KDHET. Our results indicate that a reduction of brain VAChT protein to the levels found in VAChT KDHOM mice alters the epileptic response to PILO. Thus, fine-tuning modulation of cholinergic tone can affect the susceptibility of epileptic responses to pilocarpine. (c) 2008 Elsevier Ireland Ltd. All rights reserved.