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Organic electrochemical transistors (OECTs) have emerged as powerful tools for biosignal amplification, including electrocorticography (ECoG). However, their widespread application has been limited by the complexities associated with existing fabrication techniques, restricting accessibility and scalability. Here, we introduce a novel all-planar, all-printed high-performance OECT device that significantly enhances the accuracy and sensitivity of ECoG recordings. Achieved through an innovative three-step drop-on-demand inkjet printing process on flexible substrates, our device offers a rapid response time of 0.5 ms, a compact channel area of 1950 µm2, and is characterized by a transconductance of 11 mS. This process not only simplifies integration but also reduces costs. Our optimized in-plane gate voltage control facilitates operation at peak transconductance, which elevates the signal-to-noise ratio (SNR) by up to 133%. In vivo evaluations in a rat model of seizure demonstrate the device's performance in recording distinct electrographic phases, surpassing the capabilities of PEDOT:PSS-coated gold-based ultralow impedance passive electrodes, achieving a high SNR of 48 db. Our results underscore the potential of Inkjet-printed OECTs in advancing the accessibility and accuracy of diagnostic tools that could enhance patient care by facilitating timely detection of neurological conditions.
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Toxoplasma gondii is the etiologic agent of toxoplasmosis, a highly prevalent parasitosis. Toxoplasma gondii (T. gondii) transits in the brain from acute (AT) to chronic toxoplasmosis (CT), under host immune control. In immunocompromised patients, reactivation of CT is potentially life-threatening. Behavioral and neurological complications have been associated with CT. Furthermore, an effective treatment targeting CT is still lacking. We previously reported the efficacy of imiquimod against CT. Here, we demonstrate the molecular effects of imiquimod or imiquimod followed by the clinically used combination of sulfadiazine and pyrimethamine (SDZ + PYR) on CT-associated behavior in a rat model. Imiquimod decreased the number of cysts in the brains of chronically infected rats due to an induced reactivation of bradyzoites into tachyzoites. Importantly, this decrease was more pronounced in rats treated with imiquimod followed by SDZ + PYR. Rats chronically infected with T. gondii exhibited an anxiety-like behavior. Notably, treatment with imiquimod reversed this behavior aberrancy, with even a more pronounced effect with imiquimod followed by SDZ/PYR. Similarly, rats chronically infected with T. gondii exhibited learning deficits, and imiquimod alone or followed by SDZ/PYR reversed this behavior. Our results enhance our knowledge of the implications of CT on behavioral aberrancies and highlight the potency of imiquimod followed by SDZ + PYR on these CT-associated complications.
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BACKGROUND: The timely abortion of status epilepticus (SE) is essential to avoid brain damage and long-term neurodevelopmental sequalae. However, available anti-seizure treatments fail to abort SE in 30% of children. Given the role of the tropomyosin-related kinase B (TrkB) receptor in hyperexcitability, we investigated if TrkB blockade with lestaurtinib (CEP-701) enhances the response of SE to a standard treatment protocol and reduces SE-related brain injury. METHODS: SE was induced with intra-amygdalar kainic acid in postnatal day 45 rats under continuous electroencephalogram (EEG). Fifteen min post-SE onset, rats received intraperitoneal (i.p.) CEP-701 (KCEP group) or its vehicle (KV group). Controls received CEP-701 or its vehicle following intra-amygdalar saline. All groups received two i.p. doses of diazepam, followed by i.p. levetiracetam at 15 min intervals post-SE onset. Hippocampal TrkB dimer to monomer ratios were assessed by immunoblot 24 hr post-SE, along with neuronal densities and glial fibrillary acid protein (GFAP) levels. RESULTS: SE duration was 50% shorter in the KCEP group compared to KV (p < 0.05). Compared to controls, SE induced a 1.5-fold increase in TrkB dimerization in KV rats (p < 0.05), but not in KCEP rats which were comparable to controls (p > 0.05). The KCEP group had lower GFAP levels than KV (p < 0.05), and both were higher than controls (p < 0.05). KCEP and KV rats had comparable hippocampal neuronal densities (p > 0.05), and both were lower than controls (p < 0.05). CONCLUSIONS: Given its established human safety, CEP-701 is a promising adjuvant drug for the timely abortion of SE and the attenuation of SE-related brain injury.
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Lesões Encefálicas , Estado Epiléptico , Criança , Humanos , Ratos , Animais , Furanos/efeitos adversos , Furanos/metabolismo , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/metabolismo , Diazepam/farmacologia , Diazepam/uso terapêutico , Lesões Encefálicas/metabolismo , Hipocampo/metabolismoRESUMO
BACKGROUND: Rasmussen encephalitis (RE) is a rare progressive presumed autoimmune disorder characterized by pharmacoresistant epilepsy and progressive motor and cognitive deterioration. Despite immunomodulation, more than half of the patients with RE ultimately require functional hemispherotomy. In this study, we evaluated the potential beneficial effects of early initiation of immunomodulation in slowing disease progression and preventing the need for surgical interventions. METHODS: A retrospective chart review over a 10-year period was conducted at the American University of Beirut Medical Center to identify patients with RE. Data were collected on seizure characteristics, neurological deficits, electroencephalography, brain magnetic resonance imaging results (including volumetric analyses for an objective assessment of radiographic progression), and treatment modalities. RESULTS: Seven patients met the inclusion criteria for RE. All patients received intravenous immunoglobulins (IVIGs) as soon as the diagnosis was entertained. Five patients with only monthly to weekly seizures at the time of IVIG initiation had favorable outcomes without resorting to surgery, along with a relative preservation of the gray matter volumes in the affected cerebral hemispheres. Motor strength was preserved in those patients, and three were seizure free at their last follow-up visit. The two patients who required hemispherotomy were already severely hemiparetic and experiencing daily seizures at the time of IVIG initiation. CONCLUSIONS: Our data suggest that the early initiation of IVIG as soon as a diagnosis of RE is suspected, and particularly before the appearance of motor deficits and intractable seizures, can maximize the beneficial effects of immunomodulation in terms of controlling seizures and reducing the rate of cerebral atrophy.
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Encefalite , Imunoglobulinas Intravenosas , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Estudos Retrospectivos , Encefalite/diagnóstico por imagem , Encefalite/tratamento farmacológico , Convulsões/tratamento farmacológico , Imageamento por Ressonância Magnética , Progressão da DoençaRESUMO
BACKGROUND: Seizures occur in up to 13% of children with non-central nervous system (CNS) malignancies, but little is known about their causes and optimal diagnostic and therapeutic approaches. Here we sought to determine etiologies and clinical trajectories of new-onset seizures in this patient population. METHODS: A retrospective chart review over a 10-year period was conducted at the American University of Beirut Medical Center to identify children with non-CNS malignancies and at least one new-onset seizure. Data were collected on the underlying malignancy, seizure etiology, clinical course, treatments, electroencephalograms, and brain imaging. RESULTS: New-onset seizures occurred in 56 children (2-year median follow-up), most commonly in the context of acute lymphoblastic leukemia, lymphomas, and sarcomas. In 19 children, the first seizure consisted of status epilepticus. The most common etiologies were cerebrovascular accidents, posterior reversible encephalopathy syndrome, and metastasis. Forty-nine patients received anti-seizure medications (ASMs). Withdrawal of ASMs was successful in 19 children with normal initial or follow-up brain imaging but failed in three patients with persistent brain lesions. The remaining children, all of whom except two had structural brain abnormalities, received chronic ASMs and remained seizure free for a median period of 2 years at the last follow-up in survivors. CONCLUSIONS: Not only are seizures in children with non-CNS cancers often indicative of a serious brain insult, but they can also be challenging in the form of status epilepticus. An urgent diagnostic evaluation is therefore needed to expedite treatment, which should be tailored to the chronicity of the underlying cause.
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Síndrome da Leucoencefalopatia Posterior , Estado Epiléptico , Criança , Humanos , Estudos Retrospectivos , Centros de Atenção Terciária , Estado Epiléptico/tratamento farmacológico , Eletroencefalografia , Anticonvulsivantes/uso terapêuticoRESUMO
The effects of non-convulsive status epilepticus (NCSE) on the developing brain remain largely elusive. Here we investigated potential hippocampal injury and learning deficits following one or two episodes of NCSE in periadolescent rats. Non-convulsive status epilepticus was induced with subconvulsive doses of intrahippocampal kainic acid (KA) under continuous EEG monitoring in postnatal day 43 (P43) rats. The RKA group (repeated KA) received intrahippocampal KA at P43 and P44, the SKA group (single KA injection) received KA at P43 and an intrahippocampal saline injection at P44. Controls were sham-treated with saline. The modified two-way active avoidance (MAAV) test was conducted between P45 and P52 to assess learning of context-cued and tone-signaled electrical foot-shock avoidance. Histological analyses were performed at P52 to assess hippocampal neuronal densities, as well as potential reactive astrocytosis and synaptic dysfunction with GFAP (glial fibrillary acidic protein) and synaptophysin (Syp) staining, respectively. Kainic acid injections resulted in electroclinical seizures characterized by behavioral arrest, oromotor automatisms and salivation, without tonic-clonic activity. Compared to controls, both the SKA and RKA groups had lower rates of tone-signaled shock avoidance (pâ¯<â¯0.05). In contextual testing, SKA rats were comparable to controls (pâ¯>â¯0.05), but the RKA group had learning deficits (pâ¯<â¯0.05). Hippocampal neuronal densities were comparable in all groups. Compared to controls, both the SKA and RKA groups had higher hippocampal GFAP levels (pâ¯<â¯0.05). The RKA group also had lower hippocampal Syp levels compared to the SKA and control groups (pâ¯<â¯0.05), which were comparable (pâ¯>â¯0.05). We show that hippocampal NCSE in periadolescent rats results in a seizure burden-dependent hippocampal injury accompanied by cognitive deficits. Our data suggest that the diagnosis and treatment of NCSE should be prompt.
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Estado Epiléptico , Animais , Hipocampo , Ácido Caínico/toxicidade , Neurônios , Ratos , Convulsões , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/complicaçõesRESUMO
Available two-way active avoidance paradigms do not provide contextual testing, likely due to challenges in performing repetitive trials of context exposure. To incorporate contextual conditioning in the two-way shuttle box, we contextually modified one of the chambers of a standard two-chamber rat shuttle box with visual cues consisting of objects and black and white stripe patterns. During the 5 training days, electrical foot shocks were delivered every 10 s in the contextually modified chamber but were signaled by a tone in the plain chamber. Shuttling between chambers prevented an incoming foot shock (avoidance) or aborted an ongoing one (escape). During contextual retention testing, rats were allowed to freely roam in the box. During auditory retention testing, visual cues were removed, and tone-signaled shocks were delivered in both chambers. Avoidance gradually replaced escape or freezing behaviors reaching 80% on the last training day in both chambers. Rats spent twice more time in the plain chamber during contextual retention testing and had 90% avoidance rates during auditory retention testing. Our modified test successfully assesses both auditory and contextual two-way active avoidance. By efficiently expanding its array of outcomes, our novel test will complement standard two-way active avoidance in mechanistic studies and will improve its applications in translational research.
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Post-traumatic epilepsy (PTE) and neurocognitive deficits are devastating sequelae of head injuries that are common in adolescents. Investigating desperately needed treatments is hindered by the difficulties in inducing PTE in rodents and the lack of established immature rat models of pediatric PTE. Hemorrhage is a significant risk factor for PTE, but compared to humans, rats are less prone to bleeding because of their rapid blood coagulation system. In this study, we promoted bleeding in the controlled cortical impact (CCI) closed-head injury model with a 20 min pre-impact 600 IU/kg intraperitoneal heparin injection in postnatal day 35 (P35) periadolescent rats, given the preponderance of such injuries in this age group. Temporo-parietal CCI was performed post-heparin (HTBI group) or post-saline (TBI group). Controls were subjected to sham procedures following heparin or saline administration. Continuous long-term EEG monitoring was performed for 3 months post-CCI. Sensorimotor testing, the Morris water maze, and a modified active avoidance test were conducted between P80 and P100. Glial fibrillary acidic protein (GFAP) levels and neuronal damage were also assessed. Compared to TBI rats, HTBI rats had persistently higher EEG spiking and increased hippocampal GFAP levels (p < 0.05). No sensorimotor deficits were detected in any group. Compared to controls, both HTBI and TBI groups had a long-term hippocampal neuronal loss (p < 0.05), as well as contextual and visuospatial learning deficits (p < 0.05). The hippocampal astrogliosis and EEG spiking detected in all rats subjected to our hemorrhage-promoting procedure suggest the emergence of hyperexcitable networks and pave the way to a periadolescent PTE rat model.
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Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/fisiopatologia , Suscetibilidade a Doenças , Hemorragia/etiologia , Fatores Etários , Animais , Biomarcadores , Biópsia , Lesões Encefálicas Traumáticas/diagnóstico , Modelos Animais de Doenças , Eletroencefalografia , Proteína Glial Fibrilar Ácida/metabolismo , Hemorragia/diagnóstico , Imuno-Histoquímica , Aprendizagem em Labirinto , Neurônios/metabolismo , RatosRESUMO
Traumatic brain injury (TBI) remains a significant leading cause of death and disability among adults and children globally. To date, there are no Food and Drug Administration-approved drugs that can substantially attenuate the sequelae of TBI. The innumerable challenges faced by the conventional de novo discovery of new pharmacological agents led to the emergence of alternative paradigm, which is drug repurposing. Repurposing of existing drugs with well-characterized mechanisms of action and human safety profiles is believed to be a promising strategy for novel drug use. Compared to the conventional discovery pathways, drug repurposing is less costly, relatively rapid, and poses minimal risk of the adverse outcomes to study on participants. In recent years, drug repurposing has covered a wide range of neurodegenerative diseases and neurological disorders including brain injury. This review highlights the advances in drug repurposing and presents some of the promising candidate drugs for potential TBI treatment along with their possible mechanisms of neuroprotection. Edaravone, glyburide, ceftriaxone, levetiracetam, and progesterone have been selected due to their potential role as putative TBI neurotherapeutic agents. These drugs are Food and Drug Administration-approved for purposes other than brain injuries; however, preclinical and clinical studies have shown their efficacy in ameliorating the various detrimental outcomes of TBI.
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Lesões Encefálicas Traumáticas , Lesões Encefálicas , Fármacos Neuroprotetores , Adulto , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Criança , Reposicionamento de Medicamentos , Humanos , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , ProgesteronaRESUMO
BACKGROUND: Neonatal seizures are frequently encountered in the neonatal intensive care unit and may be associated with serious long-term neurological sequelae. Response to treatment continues to be modest, and treatment guidelines remain unclear. The use of levetiracetam has been on the rise in the past several years due to its favorable safety profile in the face of limited data on its efficacy and optimal dosing regimens. Unlike the older age groups, the benefit of escalating to high-dose levetiracetam of 80-100 mg/kg/day in neonates not responding to the standard used dosing regimen (40-60 mg/kg/day) is not studied. We sought to investigate the safety and efficacy of levetiracetam escalation to high dose regimens for neonatal seizures. METHODS: A retrospective chart review over a 7-year period was conducted at the American University of Beirut to identify neonates with electrographically proven seizures treated with levetiracetam. Data was collected on electroclinical seizure characteristics, underlying etiology, seizure control, other anti-seizure medications, and adverse effects. RESULTS: Electronic chart review revealed a total of 15 neonates with electrographically confirmed seizures treated with levetiracetam, with escalation to high doses in seven. As a first line drug, levetiracetam monotherapy terminated seizures in six out 10 neonates, two of whom had complete seizure cessation only after escalation to high doses of 80 or 100 mg/kg/day. When used in combination with other anti-seizure medications, four out of five neonates achieved complete seizure cessation upon escalation to high doses of levetiracetam. No adverse effects were noted. CONCLUSIONS: In neonates not responding to the standard used levetiracetam doses, incremental increases to 80-100 mg/kg/day may be considered. Prospective studies are needed to confirm the promising role of such high dosing regimens, and to better elucidate the role of levetiracetam in neonatal seizures.
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Anticonvulsivantes , Levetiracetam , Piracetam , Idoso , Anticonvulsivantes/efeitos adversos , Humanos , Recém-Nascido , Levetiracetam/uso terapêutico , Piracetam/uso terapêutico , Estudos Prospectivos , Estudos Retrospectivos , Convulsões/tratamento farmacológicoRESUMO
Prediabetes is a highly prevalent stage of early metabolic dysfunction that poses a high risk for cardiovascular and cognitive impairment without a clear pathological mechanism. Here, we used a non-obese prediabetic rat model previously developed in our laboratory to examine this mechanism. These rats were subjected to a mild metabolic challenge leading to hyperinsulinemia without hyperglycemia or obesity. This was associated with impaired hippocampal-dependent cognitive functions together with an augmented cerebrovascular myogenic tone. Consequently, hippocampal expression of hypoxia-inducible factor-1α increased, together with markers of mitochondrial dysfunction and oxidative stress. In parallel, the phosphorylation of Akt and mTOR increased in the prediabetic rat hippocampus alongside increased expression of p62 and LC3 puncta indicating a possible repression of autophagic flux. Neuroinflammation and neuronal apoptosis were detected in the hippocampal CA1 area as increased CD68 and IBA-1 staining, as well as increased TUNEL staining and caspase-3 activity, respectively. Treatment with metformin or pioglitazone, at a previously determined vasculoprotective non-hypoglycemic dose, reversed the cerebrovascular and hippocampal molecular alterations and ameliorated cognitive function. The present study proposes a mechanistic framework whereby prediabetic cerebrovascular impairment potentially leads to a mild hypoxic state that is exacerbated by the metabolic dysfunction-driven suppression of neuronal autophagy leading to cognitive impairment.
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Autofagia/fisiologia , Barreira Hematoencefálica/metabolismo , Transtornos Cerebrovasculares/metabolismo , Disfunção Cognitiva/metabolismo , Hipoglicemiantes/uso terapêutico , Estado Pré-Diabético/metabolismo , Animais , Autofagia/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Transtornos Cerebrovasculares/tratamento farmacológico , Disfunção Cognitiva/tratamento farmacológico , Modelos Animais de Doenças , Hipoglicemiantes/farmacologia , Masculino , Artéria Cerebral Média/efeitos dos fármacos , Artéria Cerebral Média/metabolismo , Estado Pré-Diabético/tratamento farmacológico , Distribuição Aleatória , Ratos , Ratos Sprague-DawleyRESUMO
Psychiatric and cognitive disturbances are the most common comorbidities of epileptic disorders in children. The successful treatment of these comorbidities faces many challenges including their etiologically heterogonous nature. Translational neurobehavioral research in age-tailored and clinically relevant rodent seizure models offers a controlled setting to investigate emotional and cognitive behavioral disturbances, their causative factors, and potentially novel treatment interventions. In this review, we propose a conceptual framework that provides a nonsubjective approach to rodent emotional behavioral testing with a focus on the clinically relevant outcome of behavioral response adaptability. We also describe the battery of neurobehavioral tests that we tailored to seizure models with prominent amygdalo-hippocampal involvement, including testing panels for anxiety-like, exploratory, and hyperactive behaviors (the open-field and light-dark box tests), depressive-like behaviors (the forced swim test), and visuospatial navigation (Morris water maze). The review also discusses the modifications we introduced to active avoidance testing in order to simultaneously test auditory and hippocampal-dependent emotionally relevant learning and memory. When interpreting the significance and clinical relevance of the behavioral responses obtained from a given testing panel, it is important to avoid a holistic disease-based approach as a specific panel may not necessarily mirror a disease entity. The analysis of measurable behavioral responses has to be performed in the context of outcomes obtained from multiple related and complementary neurobehavioral testing panels. Behavioral testing is also complemented by mechanistic electrophysiological and molecular investigations.
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Comportamento Animal , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/psicologia , Emoções , Epilepsia/complicações , Fatores Etários , Animais , Transtornos Cognitivos/diagnóstico , Modelos Animais de Doenças , Humanos , Testes Neuropsicológicos , RoedoresRESUMO
Rodent seizure models that pathologically and behaviorally recapitulate age-tailored epileptic disorders are used by us and others to advance our understanding of the chronobiology and mechanisms of epileptic seizure emergence and their comorbidities and to investigate potential novel treatment strategies. Obtaining prolonged continuous electroencephalogram (EEG) tracings over months is essential in this line of translational research, particularly to assess the relation between electrographic changes and the development of seizures and their various psychiatric and cognitive comorbidities in models where seizures gradually emerge over weeks following brain insults. Here we describe our approach to electrode implantation and wiring in order to successfully obtain high-quality continuous EEG tracings in rats for prolonged periods. A detailed stepwise methodological description is provided with a special focus on the details that help most in avoiding notorious pitfalls such as premature EEG cable disconnections and a poor signal to noise ratio.
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Modelos Animais de Doenças , Eletroencefalografia , Epilepsia/complicações , Epilepsia/diagnóstico , Transtornos Mentais/diagnóstico , Animais , Comportamento Animal , Eletrodos Implantados , Eletroencefalografia/métodos , Transtornos Mentais/etiologia , RatosRESUMO
Pediatric epilepsy is associated with prominent comorbid psychiatric and cognitive disturbances. Neurobehavioral testing is employed to characterize the cognitive and emotional behavioral derangements that accompany seizures in age-tailored and clinically relevant immature rodent seizure models. In addition to dissecting the causes of the etiologically multifaceted psychiatric and cognitive comorbidities of the epilepsies, neurobehavioral panels are essential in investigating potential neuroprotective strategies, especially during neurodevelopment. Here we describe a battery of behavioral testing panels that we tailored to our rodent seizure models with prominent amygdalo-hippocampal involvement. The panels include the open field and light-dark box tests for exploratory, hyperactive, and anxiety-like behaviors, the forced swim test for depressive-like behaviors, the Morris water maze for visuospatial navigation, and the modified active avoidance test for emotionally relevant learning and acquisition of adaptive behaviors. The behavioral laboratory setup and the employed methodologies are reviewed in details, with a special focus on the potential pitfalls that should be avoided.
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Escala de Avaliação Comportamental , Comportamento Animal , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/psicologia , Modelos Animais de Doenças , Emoções , Epilepsia/complicações , Animais , Transtornos Cognitivos/diagnóstico , Camundongos , RoedoresRESUMO
BACKGROUND: The electroencephalogram (EEG) is a widely used laboratory technique in rodent models of epilepsy, traumatic brain injury (TBI), and other neurological diseases accompanied by seizures. Obtaining prolonged continuous EEG tracings over weeks to months is essential to adequately answer research questions related to the chronobiology of seizure emergence, and to the effect of potential novel treatment strategies. Current EEG recording methods include wired and the more recent but very costly wireless technologies. Wired continuous long-term EEG in rodents remains the mainstay approach but is often technically challenging due to the notorious frequent EEG cable disconnections from the rodent's head, and to poor signal-to-noise ratio especially when simultaneously monitoring multiple animals. Premature EEG cable disconnections and cable movement-related artifacts result from the animal's natural mobility, and subsequent tension on the EEG wires, as well as from potential vigorous and frequent seizures. These challenges are often accompanied by injuries to the scalp, and result in early terminations of costly experiments. RESULTS: Here we describe an enhanced customized swivel-balance EEG-cage system that allows tension-free rat mobility. The cage setup markedly improves the safety and longevity of current existing wired continuous long-term EEG. Prevention of EEG cable detachments is further enhanced by a special attention to surgical electrode anchoring to the skull. In addition to mechanically preventing premature disconnections, the detailed stepwise approach to the electrical shielding, wiring and grounding required for artifact-free high signal-to-noise ratio recordings is also included. The successful application of our EEG cage system in various rat models of brain insults and epilepsy is described with illustrative high quality tracings of seizures and electrographic patterns obtained during continuous and simultaneous monitoring of multiple rats early and up to 3 months post-brain insult. CONCLUSION: Our simple-to-implement key modifications to the EEG cage setup allow the safe acquisition of substantial high quality wired EEG data without resorting to the still costly wireless technologies.
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Eletroencefalografia/instrumentação , Modelos Animais , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiopatologia , Eletrodos Implantados , Epilepsia/fisiopatologia , Desenho de Equipamento , Abrigo para Animais , Masculino , Movimento , Ratos , Ratos Sprague-Dawley , Convulsões/fisiopatologiaRESUMO
Hypoxic encephalopathy of the newborn is a major cause of long-term neurological sequelae. We have previously shown that CEP-701 (lestaurtinib), a drug with an established safety profile in children, attenuates short-term hyperexcitability and tropomyosin-related kinase B (TrkB) receptor activation in a well-established rat model of early life hypoxic seizures (HS). Here, we investigated the potential long-term neuroprotective effects of a post-HS transient CEP-701 treatment. Following exposure to global hypoxia, 10â¯day old male Sprague-Dawley pups received CEP-701 or its vehicle and were sequentially subjected to the light-dark box test (LDT), forced swim test (FST), open field test (OFT), Morris water maze (MWM), and the modified active avoidance (MAAV) test between postnatal days 24 and 44 (P24-44). Spontaneous seizure activity was assessed by epidural cortical electroencephalography (EEG) between P50 and 100. Neuronal density and glial fibrillary acidic protein (GFAP) levels were evaluated on histological sections in the hippocampus, amygdala, and prefrontal cortex at P100. Vehicle-treated hypoxic rats exhibited significantly increased immobility in the FST compared with controls, and post-HS CEP-701 administration reversed this HS-induced depressive-like behavior (pâ¯<â¯0.05). In the MAAV test, CEP-701-treated hypoxic rats were slower at learning both context-cued and tone-signaled shock-avoidance behaviors (pâ¯<â¯0.05). All other behavioral outcomes were comparable, and no recurrent seizures, neuronal loss, or increase in GFAP levels were detected in any of the groups. We showed that early life HS predispose to long-lasting depressive-like behaviors, and that these are prevented by CEP-701, likely via TrkB modulation. Future mechanistically more specific studies will further investigate the potential role of TrkB signaling pathway modulation in achieving neuroprotection against neonatal HS, without causing neurodevelopmental adverse effects.
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Carbazóis/uso terapêutico , Cognição/efeitos dos fármacos , Emoções/efeitos dos fármacos , Hipóxia/tratamento farmacológico , Convulsões/tratamento farmacológico , Animais , Animais Recém-Nascidos , Carbazóis/farmacologia , Cognição/fisiologia , Emoções/fisiologia , Furanos , Hipóxia/complicações , Hipóxia/psicologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Ratos , Ratos Sprague-Dawley , Convulsões/etiologia , Convulsões/psicologiaRESUMO
Hyperekplexia is a rare neurogenetic disorder characterized by startle. Accurate diagnosis of this notorious mimicker of epilepsy is important to prevent life-threatening apnoea. We report a novel case of concomitant GLRA1-related hyperkeplexia and myoclonic epilepsy. A toddler with daily paroxysms of head drops and falls presented with epileptic myoclonus on EEG, however, whole-exome sequencing revealed hyperekplexia-related GLRA1 mutation. The boy eventually developed spells induced by noise and surprise. All his spells remitted upon treatment with clonazepam. Paediatricians and paediatric neurologists should be aware of this possible mixed presentation in order to appropriately tailor medication regimens and treatment goals. [Published with video sequence on www.epilepticdisorders.com].
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Epilepsias Mioclônicas/diagnóstico , Hiperecplexia/diagnóstico , Receptores de Glicina/genética , Epilepsias Mioclônicas/genética , Humanos , Hiperecplexia/genética , Lactente , MasculinoRESUMO
INTRODUCTION: Reflex epilepsies represent a form of epilepsy in which unique modes of seizure precipitation are characterized by endogenous or exogenous stimuli. Hot water epilepsy represents a subtype of reflex epilepsy in which seizure precipitation arises from the act of immersing the head with hot water. Bathing epilepsy represents another subtype of reflex epilepsy in which seizure precipitation arises from the immersion with water at lukewarm temperatures. CASE SERIES: We report on 2 boys with a unique form of bathing epilepsy characterized by the act of exiting out of water. The first patient had a family history significant for a brother with frontal lobe epilepsy. He underwent an evaluation in the epilepsy monitoring unit in which a reflex seizure was recorded while exiting the shower. This seizure was characterized by an ictal onset in the left frontal lobe and subsequent secondary generalization. The second patient initially had nonreflex seizures arising from the left temporal lobe and went on to develop reflex seizures upon exiting water. For both patients, the precipitation of seizures was independent of water or environmental temperature, exposure of specific body parts, or duration of water immersion. Both children experienced a sensation of coldness, followed by convulsive or atonic activity. CONCLUSIONS: Our cases represent a unique form of bathing epilepsy in which seizure precipitation is dependent upon exiting water.