Navegando por Autor "Queiroz, Claudio Marcos Teixeira de"

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AMPA receptors mediate passive avoidance deficits induced by sleep deprivation
(2013) Dubiela, Francisco Paulino; Queiroz, Claudio Marcos Teixeira de; Moreira, Karin Di Monteiro; Nobrega, Jose N.; Sita, Luciane Valéria; Tufik, Sergio; Hipolide, Debora Cristina
The present study addressed the effects of sleep deprivation (SD) on AMPA receptor (AMPAR) binding in brain regions associated with learning and memory, and investigated whether treatment with drugs acting on AMPAR could prevent passive avoidance deficits in sleep deprived animals. [(3)H]AMPA binding and GluR1 in situ hybridization signals were quantified in different brain regions of male Wistar rats either immediately after 96 h of sleep deprivation or after 24h of sleep recovery following 96 h of sleep deprivation. Another group of animals were sleep deprived and then treated with either the AMPAR potentiator, aniracetam (25, 50 and 100mg/kg, acute administration) or the AMPAR antagonist GYKI-52466 (5 and 10mg/kg, acute and chronic administration) before passive avoidance training. Task performance was evaluated 2h and 24h after training. A significant reduction in [(3)H]AMPA binding was found in the hippocampal formation of SD animals, while no alterations were observed in GluR1 mRNA levels. The highest dose of aniracetam (100mg/kg) reverted SD-induced impairment of passive avoidance performance in both retention tests, whereas GYKI-52466 treatment had no effect. Pharmacological enhancement of AMPAR function may revert hippocampal-dependent learning impairments produced after SD. We argue that such effects might be associated with reduced AMPAR binding in the hippocampus of sleep deprived animals.
Association between brain morphology and electrophysiological features in Congenital Zika Virus Syndrome: a cross-sectional, observational study
(Elsevier, 2020-08) Sequerra, Eduardo Bouth; Rocha, Antonio Jhones Lima da; Medeiros, Galtieri Otavio Cunha de; Moreira Neto, Manuel; Maia, Claudia Rodrigues Souza; Arrais, Nívia Maria Rodrigues; Bezerra, Mylena Taíse Azevedo Lima; Jeronimo, Selma Maria Bezerra; Barros Filho, Allan Kardec Duailibe; Sousa, Patrícia S; Melo, Aurea Nogueira de; Queiroz, Claudio Marcos Teixeira de
Background: Intrauterine infection with the Zika virus (ZIKV) has been connected to severe brain malformations, microcephaly, and abnormal electrophysiological activity. Methods: We describe the interictal electroencephalographic (EEG) recordings of 47 children born with ZIKV-derived microcephaly. EEGs were recorded in the first year of life and correlated with brain morphology. In 31 subjects, we tested the association between computed tomography (CT) findings and interictal epileptiform discharges (IED). In eighteen, CTs were used for correlating volumetric measurements of the brainstem, cerebellum, and prosencephalon with the rate of IED. Findings: Twenty-nine out of 47 (62%) subjects were diagnosed as having epilepsy. Those subjects presented epileptiform discharges, including unilateral interictal spikes (26/29, 90%), bilateral synchronous and asynchronous interictal spikes (21/29, 72%), and hypsarrhythmia (12/29, 41%). Interestingly, 58% of subjects with clinical epilepsy were born with rhombencephalon malformations, while none of the subjects without epilepsy showed macroscopic abnormalities in this region. The presence of rhombencephalon malformation was associated with epilepsy (odds ratio of 34; 95% CI: 2 - 654). Also, the presence of IED was associated with smaller brain volumes. Age-corrected total brain volume was inversely correlated with the rate of IED during sleep. Finally, 11 of 44 (25%) subjects presented sleep spindles. We observed an odds ratio of 0·25 (95% CI: 0·06 - 1·04) for having sleep spindles given the IED presence. Interpretation: The findings suggest that certain CT imaging features are associated with an increased likelihood of developing epilepsy, including higher rates of IED and impaired development of sleep spindles, in the first year of life of CZVS subjects
Avaliação da expressão de c-Fos em diferentes modelos de indução de crise
(Universidade Federal do Rio Grande do Norte, 2023-07-14) Santos, Aryel Nayara dos; Queiroz, Claudio Marcos Teixeira de; http://lattes.cnpq.br/3384801391828521; http://lattes.cnpq.br/8484349719105274; Sequerra, Eduardo Bouth; http://lattes.cnpq.br/2028204211415978; Araújo, John Fontenele; http://lattes.cnpq.br/3347815035685882
O principal fenômeno na vida de pessoas com epilepsia é a recorrência de crises epilépticas. As crises são episódios transitórios caracterizados por sinais e/ou sintomas causados por atividade neuronal anormal e excessiva. Compreender quais estruturas neurais participam dos diferentes tipos de crise foi o objetivo do presente trabalho. Para isso, utilizamos três modelos animais de crise: o pentilenotetrazol (PTZ, que bloqueia a neurotransmissão GABAérgica), a pilocarpina (PIL, agonista muscarínico) e o ácido caínico (KAI, agonista de receptores glutamatérgicos). Nosso interesse foi avaliar o padrão de ativação neuronal, por meio da presença de um gene de expressão imediata - o c-fos, em crises induzidas por diferentes sistemas de neurotransmissão. A proteína c-Fos é rapidamente produzida em resposta à atividade neuronal e sua expressão é localizada e transitória. Assim, avaliamos a quantidade de células c-Fos+ no hipocampo, córtex, tálamo, hipotálamo e amígdala. Os resultados mostraram diferenças significativas entre os modelos de crises induzidas, com aumento significativo de células c-Fos+ nas sub-regiões do hipocampo (em especial o giro denteado), amígdala, córtex piriforme e núcleos hipotalâmicos. Os grupos PIL e KAI apresentaram um maior número de células c-Fos+ nessas áreas, em ambos os hemisférios, quando comparado ao grupo PTZ. De fato, os animais do grupo PTZ tiveram crises mais breves e menos graves que os animais PIL e KAI. O pré-tratamento com Diazepam aboliu a ocorrência de crises e a presença de células c-Fos+ após o PTZ. Animais do grupo controle (tratados com salina) não apresentaram expressão de c-Fos significativa. Em conjunto, nossos resultados sugerem uma forte associação entre a intensidade / gravidade da crise e a expressão de c-Fos em regiões corticais e subcorticais. Estudos futuros com um maior número de animais e um detalhamento dos tipos neuronais envolvidos nas crises serão necessários para melhor compreensão das redes neurais associadas à gênese, propagação, manutenção e término das crises.
Contribuição das proteínas tirosina cinases e da cálciocalmodulina cinase tipo II em modelos animais de epilepsia
(Universidade Federal de São Paulo, 2005) Queiroz, Claudio Marcos Teixeira de; Mello, Luiz Eugênio Araújo de Moraes; http://lattes.cnpq.br/3384801391828521; Caraisco, Norberto Garcia; Moraes, Márcio Flávio Dutra; Priel, Margareth Rose; Xavier, Gilberto Fernando
As epilepsias do lobo temporal são as que apresentam maior refratariedade ao tratamento farmacológico e perfazem 2/3 das intervenções cirúrgicas de epilepsia, sendo portanto de grande custo social, econômico e psicológico. Assim, modelos animais de epilepsia do lobo temporal são de grande relevância não só para o entendimento das bases neurais dessa patologia, mas também para o desenvolvimento de abordagens terapêuticas capazes de evitar a instalação da doença. Esses são os objetivos da presente dissertação de doutorado. Após um evento traumático (no caso deste trabalho, um estado de mal epiléptico), diversas alterações morfológicas e fisiológicas acontecem, caracterizando a gênese da síndrome epiléptico (epileptogênese). Dentre as alterações podemos destacar a intensa fosforilação de proteínas em resíduos de tirosina e a ativação de diferentes segundos mensageiros. Os dois primeiros capítulos desta tese descrevem a tentativa de bloquear os processos de epileptogênese por meio da inibição da fosforilação de resíduos de tirosina através do tratamento farmacológico com inibidores das tirosina cinases, a herbimicina A e o K-252a. O terceiro capítulo analisa eletrofisiologicamente o circuito neural do giro denteado em animais que apresentavam uma mutação em um sítio inibitório da proteína cálcio/calmodulina cinase do tipo II (CaMKII). No primeiro capítulo, mostramos que o tratamento agudo com herbimicina A (348μM, 5μL, icv), é capaz de bloquear a potenciação duradoura (LTP) induzida por um estímulo tetânico bem como de atenuar (~40%) a ativação neuronal (expressão de c-Fos) decorrente de um estado de mal epiléptico induzido pela administração sistêmica de pilocarpina (SE). Apesar dos significativos efeitos agudos, este tratamento mostrou-se incapaz de atenuar a freqüência de crises espontâneas, bem como o padrão de morte neuronal observado após o estado de mal epiléptico induzido pela pilocarpina. Entretanto, o tratamento com herbimicina A alterou o padrão de marcação de metais pesados (Zn+2) no hilo do giro denteado e na região de CA3 do hipocampo, porém não apresentou efeito sobre o padrão de brotamento das fibras musgosas observado na camada molecular do giro denteado. No segundo capítulo, mostramos que a herbimicina e o K- 252a modificam a atividade epileptiforme induzida pela administração intra-hipocampal de ácido caínico, sem alterar o padrão de morte neuronal. Esses resultados sugerem que o tratamento com inibidores de proteínas tirosina cinases é capaz de modificar o padrão de ativação agudo do hipocampo após um estímulo (i.e., o estado de mal epiléptico ou a LTP), porém sem qualquer efeito sobre o processo de epileptogênese. No terceiro capítulo, estudamos a excitabilidade e a plasticidade do giro denteado à estimulação da via perfurante (principal aferência da formação hipocampal) em animais que apresentam uma CaMKII geneticamente modificada. Essa proteína uma vez ativada não pode ser inibida. A caracterização eletrofisiológica demonstrou que esses animais apresentam potenciais de campo evocados no giro denteado aparentemente semelhante aos animais controle (wild-type), porém sua responsividade a padrões de estimulação em salvas e sua plasticidade apresentaram clara alteração. Essa modificação foi caracterizada por uma maior variabilidade nas respostas à trens de estimulação (freqüências de 1 e 2 Hz) e maior inibição do pulso pareado em trens de estimulação (para pulsos pareados aplicados a freqüência de 5 Hz). Além disso, conforme já descrito na literatura, mostramos que a susceptibilidade a atividade epileptiforme depende do padrão de estimulação utilizado para os diferentes animais (mutantes vs. wild-type). Assim, utilizando o modelo clássico do abrasamento demonstramos que a mutação não altera a evolução da epileptogênese. Entretanto, ao utilizarmos duas variantes de um padrão de estimulação similar à freqüência teta (5Hz, Intermittent vs. Continuous theta-burst stimulations), demonstramos a importância da mutação na manutenção da excitabilidade do giro denteado. Esses resultados destacam a importância da CaMKII na atividade epileptiforme além de sugerir novas abordagens experimentais (i.e., sensibilidade à padrões de estimulação eletrofisiológica) no estudo da epileptogênese. Em resumo, os resultados apresentados nessa tese contribuem para um melhor entendimento dos fenômenos subjacentes aos processos de plasticidade neuronal e da contribuição destes para o fenômeno de epileptogênese, além de sugerir
Disentangling chemical and electrical effects of status epilepticus-induced dentate gyrus abnormalities
(2019-11-05) Moura, Daniela M. S.; Sales, Igor R. P.; Brandão, Juliana A.; Costa, Marcos Romualdo; Queiroz, Claudio Marcos Teixeira de
In rodents, status epilepticus (SE) triggered by chemoconvulsants can differently affect the proliferation and fate of adult-born dentate granule cells (DGCs). It is unknown whether abnormal neurogenesis results from intracellular signaling associated with drug-receptor interaction, paroxysmal activity, or both. To test the contribution of these factors, we systematically compared the effects of kainic acid (KA)- and pilocarpine (PL)-induced SE on the morphology and localization of DGCs generated before or after SE in the ipsi- and contralateral hippocampi of mice. Hippocampal insult was induced by unilateral intrahippocampal (ihpc) administration of KA or PL. We employed conditional doublecortin-dependent expression of the green fluorescent protein (GFP) to label adult-born cells committed to neuronal lineage either one month before (mature DGCs) or seven days after (immature DGCs) SE. Unilateral ihpc administration of KA and PL led to bilateral epileptiform discharges and focal and generalized behavioral seizures. However, drastic granule cell layer (GCL) dispersion occurred only in the ipsilateral side of KA injection, but not in PL-treated animals. Granule cell layer dispersion was accompanied by a significant reduction in neurogenesis after SE in the ipsilateral side of KA-treated animals, while neurogenesis increased in the contralateral side of KA-treated animals and both hippocampi of PL-treated animals. The ratio of ectopic neurons in the ipsilateral hippocampus was higher among immature as compared to mature neurons in the KA model (32.8% vs. 10.0%, respectively), while the occurrence of ectopic neurons in PL-treated animals was lower than 3% among both mature and immature DGCs. Collectively, our results suggest that KA- and PL-induced SE leads to distinct cellular alterations in mature and immature DGCs. We also show different local and secondary effects of KA or PL in the histological organization of the adult DG, suggesting that these unique epilepsy models may be complementary to our understanding of the disease.
Efeitos da buspirona em modelos animais de discinesia tardia
(1999) Queiroz, Claudio Marcos Teixeira de; Frussa-Filho , Roberto
Nos últimos dois séculos, o conhecimento sobre o sistema nervoso central expandiu-se consideravelmente, possibilitando atualmente o tratamento de muitas patologias do sistema nervoso central. Uma dessas patologias, entretanto, a discinesia tardia não apresenta nenhum tratamento terapêutico de eficácia comprovada (Soares, 1997). A discinesia tardia é uma síndrome caracterizada por movimentos involuntários repetitivos, normalmente envolvendo a língua, boca e face, ocasionalmente atingindo também o pescoço, membros superiores e quadris. Acredita-se ser a discinesia tardia um efeito colateral da exposição prolongada aos antipsicóticos (neurolépticos). Essa disfunção motora pode persistir por meses ou anos após a retirada do tratamento com neuroléptico, podendo até mesmo ser irreversível (Karniol, 1979; Casey, 1985; Kane, 1995). Nesta tese de Mestrado, procuramos estudar os efeitos comportamentais da administração de buspirona sobre modelos animais de discinesia tardia. Os modelos animais utilizados foram: [1] a supersensibilidade dopaminérgica induzida por um tratamento prolongado com haloperidol e quantificada pela atividade espontânea de ratos em um campo aberto e [2] pelo comportamento estereotipado induzido pela apomorfina e [3] a quantificação dos movimentos orofaciais de ratos após um tratamento repetido com reserpina. O tratamento prolongado com buspirona per se (3.0 mg/kg, i.p., duas vezes ao dia, por 30 dias) não resultou em uma supersensibilidade comportamental em nenhum dos dois modelos animais. O tratamento concomitante de buspirona foi capaz de diminuir os sintomas da supersensibilidade dopaminérgica induzida pelo haloperidol (2.0 mg/kg, i.p., uma vez ao dia, por 30 dias) e quantificada pela atividade geral em campo aberto, mas não pelo comportamento estereotipado induzido pela apomorfina. Nos experimentos agudos, apesar de a buspirona per se diminuir tanto a atividade gera em campo aberto como o comportamento estereotipado induzido pela apomorfina, a co-administração de buspirona não foi capaz de modificar o efeitos agudos do haloperidol sobre esses dois modelos animais. No terceiro modelo, ratos foram tratados com salina ou buspirona (3.0 mg/kg, i.p., duas vezes ao dia) e veículo ou reserpina (0.1 mg/kg, s.c., dias intercalados) por 19 dias. No vigésimo dia, os animais foram observados para a quantificação de seus movimentos orofaciais: freqüência de protrusão de língua e movimentos mandibulares e duração do tremor facial. O tratamento com buspirona per se não foi capaz de induzir a movimentos orofaciais. Animais tratados com reserpina apresentaram maior freqüência de movimentos orofaciais em relação aos animais tratados com salina. A co-administração de buspirona foi capaz de atenuar o desenvolvimento da discinesia orofacial induzida pela reserpina. Verificou-se, também, que os animais tratados cronicamente com buspirona (3.0 mg/kg, i.p., duas vezes ao dia, 30 dias) desenvolvem maior resposta ao comportamento de bocejo induzido pela apomorfina. Assim, com este trabalho observamos que o tratamento prolongado com buspirona foi capaz de atenuar comportamentos dependentes da disponibilidade de dopamina endógena (atividade geral em campo aberto e movimentos orofaciais induzidos pela reserpina) provavelmente por meio de uma supersensibilidade dos receptores pré-sinápticos (sugerida pelo aumento do comportamento de bocejo induzido por apomorfina). Os dados aqui apresentados, juntamente com a literatura clínica existente até o momento, sugerem um possível papel terapêutico da buspirona no tratamento da discinesia tardia.
Electrophysiological evidence that the retrosplenial cortex displays a strong and specific activation phased with hippocampal theta during paradoxical (REM) sleep
(2017-07-20) Koike, Bruna Del Vechio; Farias, Kelly Soares; Billwiller, Francesca; Almeida-Filho, Daniel; Libourel, Paul-Antoine; Tiran-Cappello, Alix; Parmentier, Régis; Blanco, Wilfredo; Ribeiro, Sidarta Tollendal Gomes; Luppi, Pierre-Herve; Queiroz, Claudio Marcos Teixeira de
It is widely accepted that cortical neurons are similarly more activated during waking and paradoxical sleep (PS, aka REM) than during slow wave sleep (SWS). However, we recently reported using Fos labeling that only a few limbic cortical structures including the retrosplenial (RSC) and anterior cingulate (ACA) cortices contain a large number of neurons activated during PS hypersomnia. Our aim in the present study was to record local field potentials (LFPs) and unit activity from these two structures across all vigilance states in freely moving male rats to determine whether the RSC and the ACA are electrophysiologically specifically active during basal PS episodes. We found that theta power was significantly higher during PS than during active waking (aWK) similarly in the RSC and hippocampus (HPC) but not in ACA. Phase-amplitude coupling between HPC theta and gamma oscillations strongly and specifically increased in RSC during PS compared with aWK. It did not occur in ACA. Further, 68% and 43% of the units recorded in the RSC and ACA were significantly more active during PS than during aWK and SWS, respectively. In addition, neuronal discharge of RSC but not of ACA neurons increased just after the peak of hippocampal theta wave. Our results show for the first time that RSC neurons display enhanced spiking in synchrony with theta specifically during PS. We propose that activation of RSC neurons specifically during PS may play a role in the offline consolidation of spatial memories, and in the generation of vivid perceptual scenery during dreaming.
Ethological Evaluation of the Effects of Social Defeat Stress in Mice: Beyond the Social Interaction Ratio
(2016-02-03) Henriques-Alves, Aron M.; Queiroz, Claudio Marcos Teixeira de
In rodents, repeated exposure to unavoidable aggression followed by sustained sensory treat can lead to prolonged social aversion. The chronic social defeat stress model explores that phenomenon and it has been used as an animal model for human depression. However, some authors have questioned whether confounding effects may arise as the model also boosts anxiety-related behaviors. Despite its wide acceptance, most studies extract limited information from the behavior of the defeated animal. Often, the normalized occupancy around the social stimulus, the interaction zone, is taken as an index of depression. We hypothesized that this parameter is insufficient to fully characterize the behavioral consequences of this form of stress. Using an ethological approach, we showed that repeated social defeat delayed the expression of social investigation in long (10 min) sessions of social interaction. Also, the incidence of defensive behaviors, including stretched-attend posture and high speed retreats, was significantly higher in defeated mice in comparison to controls. Interestingly, a subpopulation of defeated mice showed recurrent and non-habituating stretched-attend posture and persistent flights during the entire session. Two indexes were created based on defensive behaviors to show that only recurrent flights correlates with sucrose intake. Together, the present study corroborates the idea that this model of social stress can precipitate a myriad of behaviors not readily disentangled. We propose that long sessions (>150 s) and detailed ethological evaluation during social interaction tests are necessary to provide enough information to correctly classify defeated animals in terms of resilience and susceptibility to social defeat stress.
Evidence of progenitor cell lineage rerouting in the adult mouse hippocampus after status epilepticus
(Frontiers in Neuroscience, 2020-09-18) Moura, Daniela Maria de Sousa; Brandão, Juliana Alves; Lentini, Celia; Heinrich, Christophe; Queiroz, Claudio Marcos Teixeira de; Costa, Marcos Romualdo
Cell lineage in the adult hippocampus comprises multipotent and neuron-committed progenitors. In the present work, we fate-mapped neuronal progenitors using Dcx-CreERT2 and CAG-CAT-EGFP double-transgenic mice (cDCX/EGFP). We show that 3 days after tamoxifen-mediated recombination in cDCX/EGFP adult mice, GFP+ cells in the dentate gyrus (DG) co-expresses DCX and about 6% of these cells are proliferative neuronal progenitors. After 30 days, 20% of GFP+ generated from these progenitors differentiate into GFAP+ astrocytes. Unilateral intrahippocampal administration of the chemoconvulsants kainic acid (KA) or pilocarpine (PL) triggered epileptiform discharges and led to a significant increase in the number of GFP+ cells in both ipsi and contralateral DG. However, while PL favored the differentiation of neurons in both ipsi- and contralateral sides, KA stimulated neurogenesis only in the contralateral side. In the ipsilateral side, KA injection led to an unexpected increase of astrogliogenesis in the Dcx-lineage. We also observed a small number of GFP+/GFAP+ cells displaying radial-glia morphology ipsilaterally 3 days after KA administration, suggesting that some Dcx-progenitors could regress to a multipotent stage. The boosted neurogenesis and astrogliogenesis observed in the Dcx-lineage following chemoconvulsants administration correlated, respectively, with preservation or degeneration of the parvalbuminergic plexus in the DG. Increased inflammatory response, by contrast, was observed both in the DG showing increased neurogenesis or astrogliogenesis. Altogether, our data support the view that cell lineage progression in the adult hippocampus is not unidirectional and could be modulated by local network activity and GABA-mediated signaling
Hippocampus-retrosplenial cortex interaction is increased during phasic REM and contributes to memory consolidation
(Springer Science and Business Media LLC, 2021-06-22) Almeida Filho, Daniel Gomes de; Koike, Bruna Del Vechio; Billwiller, Francesca; Farias, Kelly Soares; Sales, Igor Rafael Praxedes de; Luppi, Pierre-Hervé; Ribeiro, Sidarta Tollendal Gomes; Queiroz, Claudio Marcos Teixeira de
Hippocampal (HPC) theta oscillation during post-training rapid eye movement (REM) sleep supports spatial learning. Theta also modulates neuronal and oscillatory activity in the retrosplenial cortex (RSC) during REM sleep. To investigate the relevance of theta-driven interaction between these two regions to memory consolidation, we computed the Granger causality within theta range on electrophysiological data recorded in freely behaving rats during REM sleep, both before and after contextual fear conditioning. We found a training-induced modulation of causality between HPC and RSC that was correlated with memory retrieval 24 h later. Retrieval was proportional to the change in the relative influence RSC exerted upon HPC theta oscillation. Importantly, causality peaked during theta acceleration, in synchrony with phasic REM sleep. Altogether, these results support a role for phasic REM sleep in hippocampo-cortical memory consolidation and suggest that causality modulation between RSC and HPC during REM sleep plays a functional role in that phenomenon
Human Brain Expansion during Evolution Is Independent of Fire Control and Cooking
(Universidade Federal do Rio Grande do Norte, 2016) Cornélio, Alianda M.; Bittencourt-Navarrete, Ruben E. de; Brum, Ricardo de Bittencourt; Queiroz, Claudio Marcos Teixeira de; Costa, Marcos Romualdo
What makes humans unique? This question has fascinated scientists and philosophers for centuries and it is still a matter of intense debate. Nowadays, human brain expansion during evolution has been acknowledged to explain our empowered cognitive capabilities. The drivers for such accelerated expansion remain, however, largely unknown. In this sense, studies have suggested that the cooking of food could be a pre-requisite for the expansion of brain size in early hominins. However, this appealing hypothesis is only supported by a mathematical model suggesting that the increasing number of neurons in the brain would constrain body size among primates due to a limited amount of calories obtained from diets. Here, we show, by using a similar mathematical model, that a tradeoff between body mass and the number of brain neurons imposed by dietary constraints during hominin evolution is unlikely. Instead, the predictable number of neurons in the hominin brain varies much more in function of foraging efficiency than body mass. We also review archeological data to show that the expansion of the brain volume in the hominin lineage is described by a linear function independent of evidence of fire control, and therefore, thermal processing of food does not account for this phenomenon. Finally, we report experiments in mice showing that thermal processing of meat does not increase its caloric availability in mice. Altogether, our data indicate that cooking is neither sufficient nor necessary to explain hominin brain expansion
Identification of hypsarrhythmia in children with microcephaly infected by zika virus
(2019-02-28) Sousa, Gean Carlos; Queiroz, Claudio Marcos Teixeira de; Sousa, Patrícia; Lima, Priscila; Silva, Antônio Augusto Moura da; Pires, Nilviane; Barros, Allan Kardec
Hypsarrhythmia is an electroencephalographic pattern specific to some epileptic syndromes that affect children under one year of age. The identification of this pattern, in some cases, causes disagreements between experts, which is worrisome since an inaccurate diagnosis can bring complications to the infant. Despite the difficulties in visually identifying hypsarrhythmia, options of computerized assistance are scarce. Aiming to collaborate with the recognition of this electropathological pattern, we propose in this paper a mathematical index that can help electroencephalography experts to identify hypsarrhythmia. We performed hypothesis tests that indicated significant differences in the groups under analysis, where the p-values were found to be extremely small.
Interleukin-12 modulates sleep–wake activity and improves performance in a memory task
(Springer Science and Business Media LLC, 2024-11) Esumi, Lia Assae; Queiroz, Claudio Marcos Teixeira de; Ribeiro, Daniel Araki; Hipólide, Débora Cristina
Background: Cytokines, known for their pro- and anti-inflammatory roles, are also key regulators of sleep–wake cycles. Classical pro-inflammatory cytokines, such as interleukin-1 (IL-1) and tumor necrosis factor-alpha (TNF-α), are associated with increased sleep, particularly slow-wave sleep (SWS), while anti-inflammatory cytokines, like interleukin-10 (IL-10), generally reduce sleep duration. Given the essential role of sleep in memory consolidation, this study aimed to investigate whether interleukin-12 (IL-12), a pro-inflammatory cytokine, could increase sleep duration following a memory acquisition task and subsequently improve memory performance. Male Swiss mice were surgically implanted with electrodes for electrocorticogram (ECoG) and electromyogram (EMG) recordings to track their sleep–wake cycles. After a recovery period, baseline sleep–wake activity was recorded. The mice were then randomly assigned to two groups and treated with either IL-12 (0.5 µg, i.p.) or a phosphate-buffered saline (PBS, i.p.) control, administered immediately before the multiple-trial inhibitory avoidance (MTIA) task, a behavioral test used to assess memory performance. Following the memory acquisition session, sleep–wake activity was immediately recorded for a continuous 24-h period. Results: Mice treated with IL-12 exhibited longer latency to cross into the dark compartment during the MTIA test, indicating improved memory retention compared to the control group. Interestingly, this improved performance was associated with prolonged wakefulness, particularly in the first three hours after task acquisition. Conclusion: The study shows that IL-12 can improve memory retention through prolonged wake episodes rather than increased sleep. This finding challenges the conventional understanding that sleep is the primary state for memory consolidation, suggesting that under specific conditions, wakefulness may also play a key role in supporting memory processes. Further research is needed to explore the underlying mechanisms of IL-12's cognitive effects
Intrahippocampal aniracetam does not prevent contextual fear conditioning deficit induced by sleep deprivation
(2011-08) Dubiela, F. P.; Queiroz, Claudio Marcos Teixeira de; Soares, J. C. K.; Tufik, S.; Hipólide, D. C.
Objectives: The present work addressed whether deficits in fear conditioning (FC) performance observed after sleep deprivation (SD) (Behav Brain Res. 129:171, 2002) are dependent on AMPA receptor function and therefore could be prevent by local administration of the ampakine aniracetam. Methods and Results: Under deep anesthesia, stainless steel guide cannulae were bilaterally implanted in the dorsal hippocampal CA1 region of 3-month old male Wistar rats (250-300 g). After one week of recovery, animals were sleep deprived for 96 h by the modified multiple platform method (SD condition). Control animals remained in their home cages and were allowed to sleep ad lib. (CC condition). At the end of the sleep deprivation procedure, animals received bilateral infusions of vehicle, 0.1 or 1.0 M of aniracetam (1 µL) 15 min before the contextual fear conditioning training session. The behavioral paradigm consisted of 5 tone-shock pairings (60dB/5s, 0.6mA/1s) applied at intervals of 30 s. Twenty-four hours later, animals were exposed to a contextual FC test in the same environment where the FC training took place, followed by a tone FC test in a different apparatus where 5 tones were presented. Freezing behavior, defined as time spent in complete immobility, was recorded during all FC sessions and expressed as mean freezing duration / minute. Animals were divided into 6 groups (N=7-10), accordingly to the sleep deprivation procedure (CC, SD) and treatment (vehicle, aniracetam 0.1 M and 1.0 M). Contextual FC test: an one-way ANOVA indicated significant effect of group (p<0.05). Duncan post hoc analyses revealed that SD groups (SD vh: 8.0±2.4; SD ani 0.1M: 4.3±2.2; SD ani 1.0M: 7.9±4.6) displayed less freezing response in comparison to CC groups (CC vh: 31.3±2.7; CC ani 0.1M: 21.5±5.0; CC ani 1.0M: 31.9±3.9) (p<0.05) (values are mean±SEM in seconds). Tone FC test: A two-way repeated measures ANOVA indicated no significant main effects of group (p=0.10), a significant effect of minute (p<0.05), and no significant interaction between them (p=0.80). Duncan post hoc analyses revealed that all groups displayed an increased freezing response after the tone presentation (before tone: CC vh: 10.4±2.4; CC ani 0.1M: 8.0±1.6; CC ani 1.0M: 7.4±1.8; SD vh: 5.3±1.9; SD ani 0.1M: 2.7±1.8; SD ani 1.0M: 6.8±2.1; after tone: CC vh: 48.3±4.9; CC ani 0.1M: 47.3±3.5; CC ani 1.0M: 39.4±5.7; SD vh: 35.1±7.8; SD ani 0.1M: 35.5±6.9; SD ani 1.0M: 35.9±5.3) (p<0.05) (values are mean±SEM in seconds). Conclusions: Based on previous evidence showing a promnesic effects of aniracetam on the fear conditioning task (Brain Res. 768:197, 1997), we sought to verify whether intrahippocampal treatment with this drug could prevent learning deficits induced by sleep deprivation. Contrary to our hypothesis, aniracetam treatment did not affect fear conditioning performance of sleep deprived animals. This lack of effect might be due to hippocampal AMPA receptor downregulation after sleep deprivation.
Levetiracetam reduced the basal excitability of the dentate gyrus without restoring impaired synaptic plasticity in rats with temporal lobe epilepsy
(MDPI, 2020-09) González-H, Guillermo; Contreras-García, Itzel Jatziri; Sánchez-Huerta, Karla; Queiroz, Claudio Marcos Teixeira de; Gallardo Gudiño, Luis Ricardo; Mendoza-Torreblanca, Julieta G; Zamudio, Sergio R
Temporal lobe epilepsy (TLE), the most common type of focal epilepsy, affects learning and memory; these effects are thought to emerge from changes in synaptic plasticity. Levetiracetam (LEV) is a widely used antiepileptic drug that is also associated with the reversal of cognitive dysfunction. The long-lasting effect of LEV treatment and its participation in synaptic plasticity have not been explored in early chronic epilepsy. Therefore, through the measurement of evoked field potentials, this study aimed to comprehensively identify the alterations in the excitability and the short-term (depression/facilitation) and long-term synaptic plasticity (long-term potentiation, LTP) of the dentate gyrus of the hippocampus in a lithium-pilocarpine rat model of TLE, as well as their possible restoration by LEV (1 week; 300 mg/kg/day). TLE increased the population spike (PS) amplitude (input/output curve); interestingly, LEV treatment partially reduced this hyperexcitability. Furthermore, TLE augmented synaptic depression, suppressed paired-pulse facilitation, and reduced PS-LTP; however, LEV did not alleviate such alterations. Conversely, the excitatory postsynaptic potential (EPSP)-LTP of TLE rats was comparable to that of control rats and was decreased by LEV. LEV caused a long-lasting attenuation of basal hyperexcitability but did not restore impaired synaptic plasticity in the early chronic phase of TLE
m1 acetylcholine receptor expression is decreased in hippocampal CA1 region of aged epileptic animals
(2011-08) Cavarsan, Clarissa Fantin; Avanzi, Renata Della Torre; Queiroz, Claudio Marcos Teixeira de; Xavier, Gilberto Fernando; Mello, Luiz Eugênio; Covolan, Luciene
n the present study, we investigated the possible additive effects of epilepsy and aging on the expression of m1 muscarinic acetylcholine receptors (AChR) in the rat hippocampus. Young (3 months) and Aged (20 months) male, Wistar rats were treated with pilocarpine to induce status epilepticus (SE). Immunohistochemical procedure for m1 AChR detection was performed 2 months after pilocarpine-induced SE. In the CA1 pyramidal region m1 AChR staining was significantly decreased in aged epileptic animals when compared to young epileptic and aged control rats, indicating that the aging effect is worsened by the epileptic condition. However, the Nissl-stained cell analysis indicated that the number of pyramidal CA1 neurons was similarly reduced in both epileptic groups, young and aged animals. Therefore, our data suggest that the progressive reduction of m1 AChR expression in CA1 pyramidal cells of aged epileptic rats might bear relevance to the associated progressive cognitive impairment.
Memory corticalization triggered by REM sleep: mechanisms of cellular and systems consolidation
(2018-07-19) Almeida‑Filho, Daniel G.; Queiroz, Claudio Marcos Teixeira de; Ribeiro, Sidarta Tollendal Gomes
Once viewed as a passive physiological state, sleep is a heterogeneous and complex sequence of brain states with essential efects on synaptic plasticity and neuronal functioning. Rapid-eye-movement (REM) sleep has been shown to promote calcium-dependent plasticity in principal neurons of the cerebral cortex, both during memory consolidation in adults and during post-natal development. This article reviews the plasticity mechanisms triggered by REM sleep, with a focus on the emerging role of kinases and immediate-early genes for the progressive corticalization of hippocampus-dependent memories. The body of evidence suggests that memory corticalization triggered by REM sleep is a systemic phenomenon with cellular and molecular causes.
Music Proficiency and Quantification of Absolute Pitch: A Large-Scale Study among Brazilian Musicians
(2016-10-13) Leite, Raphael B. C.; Mota-Rolim, Sergio A.; Queiroz, Claudio Marcos Teixeira de
Absolute pitch (AP) is the ability to identify and name the pitch of a sound without external reference. Often, accuracy and speed at naming isolated musical pitches are correlated with demographic, biological, and acoustical parameters to gain insight into the genesis and evolution of this ability in specific cohorts. However, the majority of those studies were conducted in North America, Europe, or Asia. To fill this gap, here we investigated the pitch-naming performance in a large population of Brazilian conservatory musicians (N = 200). As previously shown, we found that the population performance was rather a continuum than an “all-or-none” ability. By comparing the observed distribution of correct responses to a theoretical binomial distribution, we estimated the prevalence of AP as being 18% amongst regular music students. High accuracy thresholds (e.g., 85% of correct responses) yielded a prevalence of 4%, suggesting that AP might have been underestimated in previous reports. Irrespective of the threshold used, AP prevalence was higher in musicians who started their musical practice and formal musical education early in life. Finally, we compared the performance of those music students (average proficiency group) with another group of students selected to take part in the conservatory orchestra (high proficiency group, N = 30). Interestingly, the prevalence of AP was higher in the latter in comparison to the former group. In addition, even when the response was incorrect, the mean absolute deviation from the correct response was smaller in the high proficiency group compared to the average proficiency group (Glass’s delta: 0.5). Taken together, our results show that the prevalence of AP in Brazilian students is similar to other non-tonal language populations, although this measure is highly dependent on the scoring threshold used. Despite corroborating that early involvement with musical practice and formal education can foster AP ability, the present data suggest that music proficiency may also play an important role in AP expression.
O que acontece com nosso cérebro quando ouvimos música: um estudo sobre preferência musical e estados emocionais
(Universidade Federal do Rio Grande do Norte, 2018-12-17) Cruz, Alfredo Moises da; Queiroz, Claudio Marcos Teixeira de; Queiroz, Claudio Marcos Teixeira de; Leite, Raphael Bender Chagas; Cunha, Cláudia Roberta de Oliveira
O presente trabalho discutirá quais são os efeitos da música sobre o cérebro e de que forma eles contribuem para nossas escolhas musicais. Para isso, discutiremos inicialmente a física da onda sonora e de que forma esse tipo de energia é codificada em sinais neurais pelo ouvido humano. Em um segundo momento, apresentaremos a anatomia e fisiologia do sistema nervoso, com ênfase nos sistemas auditivo e motor. Em seguida, nomearemos as áreas cerebrais envolvidas com os diferentes aspectos da percepção e apreciação musical. Finalmente, apresentaremos os resultados coletados mediante um questionário fechado obtido junto a músicos e não-músicos que teve como objetivo avaliar a percepção de consonância e dissonância para intervalos e acordes com a 'preferência musical' e possíveis implicação com estados emocionais desses estudantes. Reproduzimos dados da literatura que mostram que os intervalos de 2m, 7M e o trítono eliciam maior desprazer, tanto em músicos como em não-músicos. Observamos ainda que a música é utilizada para reforçar o estado emocional dos ouvintes, isto é, que as pessoas tendem a escolher músicas com valências emocionais similares ao seu ‘estado de espírito’ (indivíduos congruentes). Quando não o fazem (incongruentes), a preferência por músicas alegres em momentos de tristeza supera, em muito, a preferência por músicas tristes em momentos de alegria. Essas proporções não se alteram em músico e não músicos. Entretanto, encontramos evidência que indivíduos congruentes são mais sensíveis ao julgamento de sons consonantes e dissonantes, isto é, apresentam maior diferença entre escores de 7M e oitava. Terminaremos discutindo as implicações dos nossos resultados para a teoria musical e para as principais teorias científicas da estética. Acreditamos que o presente trabalho contribui para um aprofundamento das teorias musicais baseadas em aspectos biológicos do ouvir.
Reduced hippocampal dentate cell proliferation and impaired spatial memory performance in aged-epileptic rats
(2013-07-26) Clarissa F. Cavarsan; Queiroz, Claudio Marcos Teixeira de; Jair Guilherme dos Santos Jr; Gilberto F. Xavier; Luiz Eugênio Mello; Luciene Covolan
Increased adult neurogenesis is observed after training in hippocampal-dependent tasks and also after acutely induced status epilepticus (SE) although the specific roles of these cells are still a matter of debate. In this study,we investigated hippocampal cell proliferation and differentiation and the spatial learning performance in young or aged chronically epileptic rats. Status was induced by pilocarpine in 3 or 20-month old rats. Either 2 or 20 months later, rats were treated with bromodeoxyuridine (BrdU) and subsequently underwent to 8- day schedule of water maze (WM) tests. As expected, learning curves were faster in young than in aged animals (P <0.001). Chronically epileptic animals exhibited impaired learning curves compared to age-matched controls. Interestingly, the duration of epilepsy (2 or 20 months) did not correlate with the memory impairment of aged-epileptic animals. The number of BrdU-positive cells was greater in young-epileptic subjects than in age-matched controls. In contrast, cell proliferation was not increased in aged-epileptic animals, irrespective of the time of SE induction. Finally, dentate cell proliferation was not related to performance in theWM. Based on the present results we conclude that even though aging and epilepsy lead to impairments in spatial learning, their effects are not additive.

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