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1.
Cell ; 185(6): 1065-1081.e23, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35245431

RESUMO

Motor behaviors are often planned long before execution but only released after specific sensory events. Planning and execution are each associated with distinct patterns of motor cortex activity. Key questions are how these dynamic activity patterns are generated and how they relate to behavior. Here, we investigate the multi-regional neural circuits that link an auditory "Go cue" and the transition from planning to execution of directional licking. Ascending glutamatergic neurons in the midbrain reticular and pedunculopontine nuclei show short latency and phasic changes in spike rate that are selective for the Go cue. This signal is transmitted via the thalamus to the motor cortex, where it triggers a rapid reorganization of motor cortex state from planning-related activity to a motor command, which in turn drives appropriate movement. Our studies show how midbrain can control cortical dynamics via the thalamus for rapid and precise motor behavior.


Assuntos
Córtex Motor , Movimento , Tálamo , Animais , Mesencéfalo , Camundongos , Córtex Motor/fisiologia , Neurônios/fisiologia , Tálamo/fisiologia
2.
Cell ; 179(6): 1382-1392.e10, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31735497

RESUMO

Distributing learning across multiple layers has proven extremely powerful in artificial neural networks. However, little is known about how multi-layer learning is implemented in the brain. Here, we provide an account of learning across multiple processing layers in the electrosensory lobe (ELL) of mormyrid fish and report how it solves problems well known from machine learning. Because the ELL operates and learns continuously, it must reconcile learning and signaling functions without switching its mode of operation. We show that this is accomplished through a functional compartmentalization within intermediate layer neurons in which inputs driving learning differentially affect dendritic and axonal spikes. We also find that connectivity based on learning rather than sensory response selectivity assures that plasticity at synapses onto intermediate-layer neurons is matched to the requirements of output neurons. The mechanisms we uncover have relevance to learning in the cerebellum, hippocampus, and cerebral cortex, as well as in artificial systems.


Assuntos
Peixe Elétrico/fisiologia , Aprendizagem , Rede Nervosa/fisiologia , Potenciais de Ação/fisiologia , Estruturas Animais/citologia , Estruturas Animais/fisiologia , Animais , Axônios/metabolismo , Fenômenos Biofísicos , Peixe Elétrico/anatomia & histologia , Feminino , Masculino , Modelos Neurológicos , Plasticidade Neuronal , Comportamento Predatório , Sensação , Fatores de Tempo
3.
J Neurosci ; 44(18)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38538143

RESUMO

Accurately decoding external variables from observations of neural activity is a major challenge in systems neuroscience. Bayesian decoders, which provide probabilistic estimates, are some of the most widely used. Here we show how, in many common settings, the probabilistic predictions made by traditional Bayesian decoders are overconfident. That is, the estimates for the decoded stimulus or movement variables are more certain than they should be. We then show how Bayesian decoding with latent variables, taking account of low-dimensional shared variability in the observations, can improve calibration, although additional correction for overconfidence is still needed. Using data from males, we examine (1) decoding the direction of grating stimuli from spike recordings in the primary visual cortex in monkeys, (2) decoding movement direction from recordings in the primary motor cortex in monkeys, (3) decoding natural images from multiregion recordings in mice, and (4) decoding position from hippocampal recordings in rats. For each setting, we characterize the overconfidence, and we describe a possible method to correct miscalibration post hoc. Properly calibrated Bayesian decoders may alter theoretical results on probabilistic population coding and lead to brain-machine interfaces that more accurately reflect confidence levels when identifying external variables.


Assuntos
Potenciais de Ação , Teorema de Bayes , Neurônios , Animais , Masculino , Ratos , Neurônios/fisiologia , Potenciais de Ação/fisiologia , Calibragem , Camundongos , Córtex Motor/fisiologia , Macaca mulatta , Hipocampo/fisiologia , Estimulação Luminosa/métodos , Modelos Neurológicos
4.
J Neurosci ; 43(29): 5319-5339, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37339877

RESUMO

Saccades are a fundamental part of natural vision. They interrupt fixations of the visual gaze and rapidly shift the image that falls onto the retina. These stimulus dynamics can cause activation or suppression of different retinal ganglion cells, but how they affect the encoding of visual information in different types of ganglion cells is largely unknown. Here, we recorded spiking responses to saccade-like shifts of luminance gratings from ganglion cells in isolated marmoset retinas and investigated how the activity depended on the combination of presaccadic and postsaccadic images. All identified cell types, On and Off parasol and midget cells, as well as a type of Large Off cells, displayed distinct response patterns, including particular sensitivity to either the presaccadic or the postsaccadic image or combinations thereof. In addition, Off parasol and Large Off cells, but not On cells, showed pronounced sensitivity to whether the image changed across the transition. Stimulus sensitivity of On cells could be explained based on their responses to step changes in light intensity, whereas Off cells, in particular, parasol and the Large Off cells, seem to be affected by additional interactions that are not triggered during simple light-intensity flashes. Together, our data show that ganglion cells in the primate retina are sensitive to different combinations of presaccadic and postsaccadic visual stimuli. This contributes to the functional diversity of the output signals of the retina and to asymmetries between On and Off pathways and provides evidence of signal processing beyond what is triggered by isolated steps in light intensity.SIGNIFICANCE STATEMENT Sudden eye movements (saccades) shift our direction of gaze, bringing new images in focus on our retinas. To study how retinal neurons deal with these rapid image transitions, we recorded spiking activity from ganglion cells, the output neurons of the retina, in isolated retinas of marmoset monkeys while shifting a projected image in a saccade-like fashion across the retina. We found that the cells do not just respond to the newly fixated image, but that different types of ganglion cells display different sensitivities to the presaccadic and postsaccadic stimulus patterns. Certain Off cells, for example, are sensitive to changes in the image across transitions, which contributes to differences between On and Off information channels and extends the range of encoded stimulus features.


Assuntos
Callithrix , Movimentos Sacádicos , Animais , Retina/fisiologia , Movimentos Oculares , Células Ganglionares da Retina/fisiologia , Estimulação Luminosa
5.
J Physiol ; 602(1): 153-181, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37987552

RESUMO

The whisker system is widely used as a model system for understanding sensorimotor integration. Purkinje cells in the crus regions of the cerebellum have been reported to linearly encode whisker midpoint, but it is unknown whether the paramedian and simplex lobules as well as their target neurons in the cerebellar nuclei also encode whisker kinematics and if so which ones. Elucidating how these kinematics are represented throughout the cerebellar hemisphere is essential for understanding how the cerebellum coordinates multiple sensorimotor modalities. Exploring the cerebellar hemisphere of mice using optogenetic stimulation, we found that whisker movements can be elicited by stimulation of Purkinje cells in not only crus1 and crus2, but also in the paramedian lobule and lobule simplex; activation of cells in the medial paramedian lobule had on average the shortest latency, whereas that of cells in lobule simplex elicited similar kinematics as those in crus1 and crus2. During spontaneous whisking behaviour, simple spike activity correlated in general better with velocity than position of the whiskers, but it varied between protraction and retraction as well as per lobule. The cerebellar nuclei neurons targeted by the Purkinje cells showed similar activity patterns characterized by a wide variety of kinematic signals, yet with a dominance for velocity. Taken together, our data indicate that whisker movements are much more prominently and diversely represented in the cerebellar cortex and nuclei than assumed, highlighting the rich repertoire of cerebellar control in the kinematics of movements that can be engaged during coordination. KEY POINTS: Excitation of Purkinje cells throughout the cerebellar hemispheres induces whisker movement, with the shortest latency and longest duration within the paramedian lobe. Purkinje cells have differential encoding for the fast and slow components of whisking. Purkinje cells encode not only the position but also the velocity of whiskers. Purkinje cells with high sensitivity for whisker velocity are preferentially located in the medial part of lobule simplex, crus1 and lateral paramedian. In the downstream cerebellar nuclei, neurons with high sensitivity for whisker velocity are located at the intersection between the medial and interposed nucleus.


Assuntos
Cerebelo , Vibrissas , Camundongos , Animais , Vibrissas/fisiologia , Fenômenos Biomecânicos , Cerebelo/fisiologia , Células de Purkinje/fisiologia , Córtex Cerebelar
6.
Epilepsia ; 65(1): 218-237, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38032046

RESUMO

OBJECTIVE: Several studies have attributed epileptic activities in temporal lobe epilepsy (TLE) to the hippocampus; however, the participation of nonhippocampal neuronal networks in the development of TLE is often neglected. Here, we sought to understand how these nonhippocampal networks are involved in the pathology that is associated with TLE disease. METHODS: A kainic acid (KA) model of temporal lobe epilepsy was induced by injecting KA into dorsal hippocampus of C57BL/6J mice. Network activation after spontaneous seizure was assessed using c-Fos expression. Protocols to induce seizure using visual or auditory stimulation were developed, and seizure onset zone (SOZ) and frequency of epileptic spikes were evaluated using electrophysiology. The hippocampus was removed to assess seizure recurrence in the absence of hippocampus. RESULTS: Our results showed that cortical and hippocampal epileptic networks are activated during spontaneous seizures. Perturbation of these networks using visual or auditory stimulation readily precipitates seizures in TLE mice; the frequency of the light-induced or noise-induced seizures depends on the induction modality adopted during the induction period. Localization of SOZ revealed the existence of cortical and hippocampal SOZ in light-induced and noise-induced seizures, and the development of local and remote epileptic spikes in TLE occurs during the early stage of the disease. Importantly, we further discovered that removal of the hippocampi does not stop seizure activities in TLE mice, revealing that seizures in TLE mice can occur independent of the hippocampus. SIGNIFICANCE: This study has shown that the network pathology that evolves in TLE is not localized to the hippocampus; rather, remote brain areas are also recruited. The occurrence of light-induced or noise-induced seizures and epileptic discharges in epileptic mice is a consequence of the activation of nonhippocampal brain areas. This work therefore demonstrates the fundamental role of nonhippocampal epileptic networks in generating epileptic activities with or without the hippocampus in TLE disease.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Camundongos , Animais , Epilepsia do Lobo Temporal/patologia , Camundongos Endogâmicos C57BL , Convulsões/metabolismo , Hipocampo/patologia , Encéfalo/patologia , Epilepsia/metabolismo , Modelos Animais de Doenças , Ácido Caínico/farmacologia
7.
Epilepsia ; 65(4): 1128-1140, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38299621

RESUMO

OBJECTIVE: Children with self-limited epilepsy characterized by centrotemporal spikes (SeLECTS) exhibit cognitive deficits in memory during the active phase, but there is currently a lack of studies and techniques to assess their memory development after well-controlled seizures. In this study, we employed eye-tracking techniques to investigate visual memory and its association with clinical factors and global intellectual ability, aiming to identify potential risk factors by examining encoding and recognition processes. METHODS: A total of 26 recruited patients diagnosed with SeLECTS who had been seizure-free for at least 2 years, along with 24 control subjects, underwent Wechsler cognitive assessment and an eye-movement-based memory task while video-electroencephalographic (EEG) data were recorded. Fixation and pupil data related to eye movements were utilized to detect distinct memory processes and subsequently to compare the cognitive performance of patients exhibiting different regression patterns on EEG. RESULTS: The findings revealed persistent impairments in visual memory among children with SeLECTS after being well controlled, primarily observed in the recognition stage rather than the encoding phase. Furthermore, the age at onset, frequency of seizures, and interictal epileptiform discharges exhibited significant correlations with eye movement data. SIGNIFICANCE: Children with SeLECTS exhibit persistent recognition memory impairment after being well controlled for the disease. Controlling the frequency of seizures and reducing prolonged epileptiform activity may improve memory cognitive development. The application of the eye-tracking technique may provide novel insights into exploring memory cognition as well as underlying mechanisms associated with pediatric epilepsy.


Assuntos
Epilepsia Rolândica , Tecnologia de Rastreamento Ocular , Humanos , Criança , Convulsões/diagnóstico , Cognição , Eletroencefalografia/métodos , Transtornos da Memória/etiologia , Transtornos da Memória/complicações , Epilepsia Rolândica/complicações , Epilepsia Rolândica/psicologia
8.
Eur Radiol ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39009880

RESUMO

OBJECTIVES: To explore the interrelationships between structural and functional changes as well as the potential neurotransmitter profile alterations in drug-naïve benign childhood epilepsy with central-temporal spikes (BECTS) patients. METHODS: Structural magnetic resonance imaging (sMRI) and resting-state functional MRI data from 20 drug-naïve BECTS patients and 33 healthy controls (HCs) were acquired. Parallel independent component analysis (P-ICA) was used to identify covarying components among gray matter volume (GMV) maps and fractional amplitude of low-frequency fluctuations (fALFF) maps. Furthermore, we explored the spatial correlations between GMV/fALFF changes derived from P-ICA and neurotransmitter maps in JuSpace toolbox. RESULTS: A significantly positive correlation (p < 0.001) was identified between one structural component (GMV_IC6) and one functional component (fALFF_IC4), which showed significant group differences between drug-naïve BECTS patients and HCs (GMV_IC6: p < 0.01; fALFF_IC4: p < 0.001). GMV_IC6 showed increased GMV in the frontal lobe, temporal lobe, thalamus, and precentral gyrus as well as fALFF_IC4 had enhanced fALFF in the cerebellum in drug-naïve BECTS patients compared to HCs. Moreover, significant correlations between GMV alterations in GMV_IC6 and the serotonin (5HT1a: p < 0.001; 5HT2a: p < 0.001), norepinephrine (NAT: p < 0.001) and glutamate systems (mGluR5: p < 0.001) as well as between fALFF alterations in fALFF_IC4 and the norepinephrine system (NAT: p < 0.001) were detected. CONCLUSION: The current findings suggest co-altered structural/functional components that reflect the correlation of language and motor networks as well as associated with the serotonergic, noradrenergic, and glutamatergic neurotransmitter systems. CLINICAL RELEVANCE STATEMENT: The relationship between anatomical brain structure and intrinsic neural activity was evaluated using a multimodal fusion analysis and neurotransmitters which might provide an important window into the multimodal neural and underlying molecular mechanisms of benign childhood epilepsy with central-temporal spikes. KEY POINTS: Structure-function relationships in drug-naïve benign childhood epilepsy with central-temporal spikes (BECTS) patients were explored. The interrelated structure-function components were found and correlated with the serotonin, norepinephrine, and glutamate systems. Co-altered structural/functional components reflect the correlation of language and motor networks and correlate with the specific neurotransmitter systems.

9.
Microb Cell Fact ; 23(1): 119, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38659027

RESUMO

BACKGROUND: Clostridium spp. has demonstrated therapeutic potential in cancer treatment through intravenous or intratumoral administration. This approach has expanded to include non-pathogenic clostridia for the treatment of various diseases, underscoring the innovative concept of oral-spore vaccination using clostridia. Recent advancements in the field of synthetic biology have significantly enhanced the development of Clostridium-based bio-therapeutics. These advancements are particularly notable in the areas of efficient protein overexpression and secretion, which are crucial for the feasibility of oral vaccination strategies. Here, we present two examples of genetically engineered Clostridium candidates: one as an oral cancer vaccine and the other as an antiviral oral vaccine against SARS-CoV-2. RESULTS: Using five validated promoters and a signal peptide derived from Clostridium sporogenes, a series of full-length NY-ESO-1/CTAG1, a promising cancer vaccine candidate, expression vectors were constructed and transformed into C. sporogenes and Clostridium butyricum. Western blotting analysis confirmed efficient expression and secretion of NY-ESO-1 in clostridia, with specific promoters leading to enhanced detection signals. Additionally, the fusion of a reported bacterial adjuvant to NY-ESO-1 for improved immune recognition led to the cloning difficulties in E. coli. The use of an AUU start codon successfully mitigated potential toxicity issues in E. coli, enabling the secretion of recombinant proteins in C. sporogenes and C. butyricum. We further demonstrate the successful replacement of PyrE loci with high-expression cassettes carrying NY-ESO-1 and adjuvant-fused NY-ESO-1, achieving plasmid-free clostridia capable of secreting the antigens. Lastly, the study successfully extends its multiplex genetic manipulations to engineer clostridia for the secretion of SARS-CoV-2-related Spike_S1 antigens. CONCLUSIONS: This study successfully demonstrated that C. butyricum and C. sporogenes can produce the two recombinant antigen proteins (NY-ESO-1 and SARS-CoV-2-related Spike_S1 antigens) through genetic manipulations, utilizing the AUU start codon. This approach overcomes challenges in cloning difficult proteins in E. coli. These findings underscore the feasibility of harnessing commensal clostridia for antigen protein secretion, emphasizing the applicability of non-canonical translation initiation across diverse species with broad implications for medical or industrial biotechnology.


Assuntos
Clostridium butyricum , Clostridium , Proteínas Recombinantes , Clostridium butyricum/genética , Clostridium butyricum/metabolismo , Clostridium/genética , Clostridium/metabolismo , Humanos , Proteínas Recombinantes/genética , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/genética , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/genética , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Administração Oral , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Esporos Bacterianos/genética , Esporos Bacterianos/imunologia , Vacinação , COVID-19/prevenção & controle , Engenharia Genética , Escherichia coli/genética , Escherichia coli/metabolismo , Regiões Promotoras Genéticas
10.
Brain Topogr ; 37(1): 116-125, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37966675

RESUMO

Magnetoencephalography (MEG) is clinically used to localize interictal spikes in discrete brain areas of epilepsy patients through the equivalent current dipole (ECD) method, but does not account for the temporal dynamics of spike activity. Recent studies found that interictal spike propagation beyond the temporal lobe may be associated with worse postsurgical outcomes, but studies using whole-brain data such as in MEG remain limited. In this pilot study, we developed a tool that visualizes the spatiotemporal dynamics of interictal MEG spikes normalized to spike-free sleep activity to assess their onset and propagation patterns in patients with temporal lobe epilepsy (TLE). We extracted interictal source data containing focal epileptiform activity in awake and asleep states from seven patients whose MEG ECD clusters localized to the temporal lobe and normalized the data against spike-free sleep recordings. We calculated the normalized activity over time per cortical label, confirmed maximal activity at onset, and mapped the activity over a 10 ms interval onto each patient's brain using a custom-built Multi-Modal Visualization Tool. The onset of activity in all patients appeared near the clinically determined epileptogenic zone. By 10 ms, four of the patients had propagated source activity restricted to within the temporal lobe, and three had propagated source activity spread to extratemporal regions. Using this tool, we show that noninvasively identifying the onset and propagation of interictal spike activity in MEG can be achieved, which may help provide further insight into epileptic networks and guide surgical planning and interventions in patients with TLE.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Humanos , Magnetoencefalografia/métodos , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/cirurgia , Projetos Piloto , Eletroencefalografia/métodos , Encéfalo , Epilepsia/cirurgia
11.
Epilepsy Behav ; 152: 109596, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38350362

RESUMO

PURPOSE: Our aim was to assess intelligence, visual perception and working memory in children with new-onset Rolandic epilepsy (RE) and children with Rolandic discharges without seizures (RD). METHODS: The participants in the study were 12 children with RE and 26 children with RD aged 4 to 10 years (all without medication and shortly after diagnosis) and 31 healthy controls. Their cognitive performance was assessed using the German versions of the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-III), the Wechsler Intelligence Scale for Children (WISC-IV), the Developmental Test of Visual Perception-2 (DTVP-2), the Developmental Test of Visual Perception-Adolescent and Adult (DTVP-A) (each according to age) and the Word Order, Hand Movements and Spatial Memory subtests of the German version of the Kaufman Assessment Battery for Children (K-ABC). RESULTS: The comparison of the entire group of children with RE/RD and the control group conducted in the first step of our analysis revealed a weaker performance of the children with RE/RD in all cognitive domains. Significant deficits, however, were found exclusively in the RD group. Compared to the controls, they performed significantly weaker regarding IQ (full scale IQ: p < 0.001; verbal IQ: p < 0.001; performance IQ: p = 0.002; processing speed: p = 0.005), visual perception (general visual perception: p = 0.005; visual-motor integration: p = 0.002) and working memory (WISC working memory: p = 0.002 and K-ABC Word Order (p = 0.010) and Hand Movements (p = 0.001) subtests. Also, the children without seizures scored significantly lower than those with seizures on the WISC Working Memory Index (p = 0.010) and on the K-ABC Word Order (p = 0.021) and Hand Movements (p = 0.027) subtests. Further analysis of our data demonstrated the particular importance of the family context for child development. Significant cognitive deficits were found only in children with RD from parents with lower educational levels. This group consistently scored lower compared to the control group regarding IQ (full scale IQ: p < 0.001; verbal IQ: p < 0.001; performance IQ: p = 0.012; processing speed: p = 0.034), visual perception (general visual perception: p = 0.018; visual-motor integration: p = 0.010) and auditory working memory (WISC working memory: p = 0.014). Furthermore, compared to the children with RE, they performed significantly weaker on verbal IQ (p = 0.020), auditory working memory consistently (WISC working memory: p = 0.027; K-ABC: Word Order: p = 0.046) as well as in one of the K-ABC spatial working memory subtests (Hand Movements: p = 0.029). Although we did not find significant deficits in children with new-onset RE compared to healthy controls, the performance of this group tended to be weaker more often. No statistically significant associations were observed between selected clinical markers (focus types: centrotemporal/other foci/laterality of foci and spread of Rolandic discharges) and cognitive test results. Except for spatial working memory, we also found no evidence that the age of our patients at the time of study participation was of significant importance to their cognitive performance. CONCLUSIONS: Our study provides some evidence that children with Rolandic discharges, with and without seizures, may be at higher risk of cognitive impairment. In addition to medical care, we emphasise early differentiated psychosocial diagnostics to provide these children and their families with targeted support if developmental problems are present.


Assuntos
Epilepsia Rolândica , Memória de Curto Prazo , Criança , Pré-Escolar , Humanos , Cognição , Eletroencefalografia , Epilepsia Rolândica/complicações , Epilepsia Rolândica/psicologia , Inteligência , Testes Neuropsicológicos , Convulsões , Percepção Visual
12.
Epilepsy Behav ; 152: 109607, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38277852

RESUMO

AIM: The current study aims to investigate the effect of Executive Functions (EFs) on Health Related Quality of Life (HRQoL) in a cohort of children with self-limited epilepsy with centrotemporal spikes (SeLECTS) and to identify possible factors that impact HRQoL specifically related to epilepsy-related variables and EFs skills. MATERIAL AND METHOD: The Pediatric Quality of Life Inventory 4.0 Generic Core Scales (PedsQL) and The Behavior Rating Inventory of Executive Function (BRIEF-2 and BRIEF-P) were completed by the parents of 129 patients with SeLECTS. Demographic variables and epilepsy-related variables were collected. RESULTS: Our sample performed in the average range across all the subscales and summary scores of the PedsQL and performed in the normal range of the BRIEF questionnaire. We observed that a lower functioning in EFs was associated with lower overall HRQoL scores. We explored the relationship between epilepsy characteristics and scores on the PedsQL. We found that the use of antiseizure medications (ASMs), longer duration of the treatment, and a higher seizure frequency were associated with a lower HRQoL. Moreover, we observed that executive dysfunction was a significant predictor of reduced HRQoL. CONCLUSION: Our results suggest the importance of the identification of patients with SeLECTS with a high level of risk for a poor HRQoL. We may now add executive dysfunction to the list of known risk factors for poor HRQoL in children with SeLECTS, along with such factors as seizure frequency, recent seizures, use of ASMs and longer duration of therapy. The early identification of children with SeLECTS at risk of a poor HRQoL could allow the activation of adequate interventions.


Assuntos
Disfunção Cognitiva , Epilepsia , Criança , Humanos , Função Executiva/fisiologia , Qualidade de Vida , Epilepsia/tratamento farmacológico , Convulsões , Inquéritos e Questionários
13.
Epilepsy Behav ; 153: 109720, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428174

RESUMO

Accelerated long-term forgetting has been studied and demonstrated in adults with epilepsy. In contrast, the question of long-term consolidation (delays > 1 day) in children with epilepsy shows conflicting results. However, childhood is a period of life in which the encoding and long-term storage of new words is essential for the development of knowledge and learning. The aim of this study was therefore to investigate long-term memory consolidation skills in children with self-limited epilepsy with centro-temporal spikes (SeLECTS), using a paradigm exploring new words encoding skills and their long-term consolidation over one-week delay. As lexical knowledge, working memory skills and executive/attentional skills has been shown to contribute to long-term memory/new word learning, we added standardized measures of oral language and executive/attentional functions to explore the involvement of these cognitive skills in new word encoding and consolidation. The results showed that children with SeLECTS needed more repetitions to encode new words, struggled to encode the phonological forms of words, and when they finally reached the level of the typically developing children, they retained what they had learned, but didn't show improved recall skills after a one-week delay, unlike the control participants. Lexical knowledge, verbal working memory skills and phonological skills contributed to encoding and/or recall abilities, and interference sensitivity appeared to be associated with the number of phonological errors during the pseudoword encoding phase. These results are consistent with the functional model linking working memory, phonology and vocabulary in a fronto-temporo-parietal network. As SeLECTS involves perisylvian dysfunction, the associations between impaired sequence storage (phonological working memory), phonological representation storage and new word learning are not surprising. This dual impairment in both encoding and long-term consolidation may result in large learning gap between children with and without epilepsy. Whether these results indicate differences in the sleep-induced benefits required for long-term consolidation or differences in the benefits of retrieval practice between the epilepsy group and healthy children remains open. As lexical development is associated with academic achievement and comprehension, the impact of such deficits in learning new words is certainly detrimental.


Assuntos
Epilepsia , Consolidação da Memória , Criança , Adulto , Humanos , Memória de Longo Prazo , Memória de Curto Prazo , Aprendizagem , Aprendizagem Verbal
14.
Neuroradiology ; 66(8): 1383-1390, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38678123

RESUMO

PURPOSE: In brain development, Myelination is the characteristic feature of white matter maturation, which plays an important role in efficient information transmitting. The white matter abnormality has been reported to be associated with self-limited epilepsy with centrotemporal spikes (SeLECTS). This study aimed to detect the altered white matter region in the SeLECTS patients by the combination of diffusion tensor imaging (DTI) and quantitative susceptibility mapping (QSM) technique. METHODS: 27 children with SeLECTS and 23 age- and gender-matched healthy children were enrolled. All participants were scanned with 3.0-T MRI to acquire the structure, diffusion and susceptibility-weighted data. The susceptibility and diffusion weighted data were processed to obtain quantitative susceptibility map and fraction anisotropy (FA) map. Then voxel-wise tract-based spatial statistics (TBSS) were used to analyze quantitative susceptibility and FA data. RESULTS: Both DTI and QSM revealed extensive white matter alterations in the frontal, parietal, and temporal lobes in SeLECTS patients. The overlapped region of DTI and QSM analyses was located in the fiber tracts of the corona radiata. The FA values in this overlapped region were negatively correlated with the magnetic susceptibility values. CONCLUSION: Our results suggest that TBSS-based QSM can be employed as a novel approach for characterizing alterations in white matter in SeLECTS. And the combination of QSM and DTI can provide a more comprehensive evaluation of white matter integrity by utilizing different biophysical features.


Assuntos
Imagem de Tensor de Difusão , Substância Branca , Humanos , Imagem de Tensor de Difusão/métodos , Feminino , Masculino , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Criança , Epilepsia Rolândica/diagnóstico por imagem , Epilepsia Rolândica/fisiopatologia , Estudos de Casos e Controles , Anisotropia , Mapeamento Encefálico/métodos , Pré-Escolar , Adolescente
15.
Cereb Cortex ; 33(10): 5774-5782, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-36444721

RESUMO

Benign epilepsy with centrotemporal spikes (BECTS) is a common pediatric epilepsy syndrome that has been widely reported to show abnormal brain structure and function. However, the genetic mechanisms underlying structural and functional changes remain largely unknown. Based on the structural and resting-state functional magnetic resonance imaging data of 22 drug-naïve children with BECTS and 33 healthy controls, we conducted voxel-based morphology (VBM) and fractional amplitude of low-frequency fluctuation (fALFF) analyses to compare cortical morphology and spontaneous brain activity between the 2 groups. In combination with the Allen Human Brain Atlas, transcriptome-neuroimaging spatial correlation analyses were applied to explore gene expression profiles associated with gray matter volume (GMV) and fALFF changes in BECTS. VBM analysis demonstrated significantly increased GMV in the right brainstem and right middle cingulate gyrus in BECTS. Moreover, children with BECTS exhibited significantly increased fALFF in left temporal pole, while decreased fALFF in right thalamus and left precuneus. These brain structural and functional alterations were closely related to behavioral and cognitive deficits, and the fALFF-linked gene expression profiles were enriched in voltage-gated ion channel and synaptic activity as well as neuron projection. Our findings suggest that brain morphological and functional abnormalities in children with BECTS involve complex polygenic genetic mechanisms.


Assuntos
Transtornos Cognitivos , Epilepsia Rolândica , Humanos , Criança , Transcriptoma , Epilepsia Rolândica/diagnóstico por imagem , Epilepsia Rolândica/genética , Epilepsia Rolândica/complicações , Encéfalo/diagnóstico por imagem , Lobo Parietal , Imageamento por Ressonância Magnética
16.
Graefes Arch Clin Exp Ophthalmol ; 262(3): 927-935, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37843563

RESUMO

PURPOSE: Intraocular pressure (IOP) spikes (IOP > 30 mmHg or > 10 mmHg above baseline IOP) are a common and worrisome complication of gonioscopy-assisted transluminal trabeculotomy (GATT). The purpose of this study is to identify risk factors for IOP spikes and to describe their characteristics, management, and clinical course in a large cohort of patients. METHODS: A retrospective, single-center study which included 217 consecutive eyes of patients that underwent GATT between December 2019 and April 2022 with follow-up of at least 90 days. RESULTS: IOP spikes occurred in 52 of 217 (24%) eyes. Spikes occurred in 15.5% of patients in whom pre-operative IOP-lowering medications were continued after surgery (90 eyes), and in 29.9% in whom IOP-lowering medications were stopped after surgery (127 eyes). Spikes were diagnosed at a mean of 7.7 ± 6.5 days after surgery. All IOP spikes occurred within the first month of surgery. The mean duration of a spike was 4.9 ± 5.4 days. Management of IOP spikes included adding a mean of 3.13 ± 1.7 groups of glaucoma medications. Thirty-seven (72.5%) eyes were treated with oral carbonic anhydrase inhibitor, 11 (21.6%) were treated with IV mannitol, and anterior chamber paracentesis was performed in 16 (31.4%). Six (11.8%) eyes underwent additional glaucoma surgery to control IOP. Patients that continued their pre-operative IOP-lowering medications after surgery were 2.3 times less likely to develop a spike as compared to patients who discontinued their medications (P = 0.016). Spikes were found to be a risk factor for failure of GATT. CONCLUSIONS: IOP spikes are a common occurrence after GATT. They most commonly appear during the first two post-operative weeks and usually resolve with topical and systemic IOP-lowering treatment. The continuation of IOP-lowering medications after GATT is recommended to lower the risk of IOP spikes.


Assuntos
Glaucoma , Trabeculectomia , Humanos , Pressão Intraocular , Gonioscopia , Estudos Retrospectivos , Glaucoma/cirurgia , Câmara Anterior
17.
J Electrocardiol ; 84: 75-80, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38574633

RESUMO

In this case report, we describe a 14-year-old patient with a novel RyR2 gene mutation (c.6577G > T/p.Val2193Leu), identified through a comprehensive review of medical history, examination findings, and follow-up data. The pathogenic potential of this mutation, which results in the loss of some interatomic forces and compromises the closure of the RyR2 protein pore leading to calcium leakage, was analyzed using the I-TASSER Suite to predict the structural changes in the protein. This mutation manifested clinically as co-morbid catecholaminergic polymorphic ventricular tachycardia (CPVT) and benign epilepsy with centrotemporal spikes (BECTS), a combination not previously documented in the same patient. While seizures were successfully managed with levetiracetam, the patient's exercise-induced syncope episodes could not be controlled with metoprolol, highlighting the complexity and challenge in managing CPVT associated with this novel RyR2 variation.


Assuntos
Mutação , Canal de Liberação de Cálcio do Receptor de Rianodina , Taquicardia Ventricular , Humanos , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Taquicardia Ventricular/genética , Taquicardia Ventricular/tratamento farmacológico , Adolescente , Masculino , Epilepsia Rolândica/genética , Epilepsia Rolândica/tratamento farmacológico , Eletrocardiografia
18.
BMC Biol ; 21(1): 84, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-37069561

RESUMO

BACKGROUND: The non-neuronal retinal pigment epithelium (RPE) functions in intimate association with retinal photoreceptors, performing a multitude of tasks critical for maintaining retinal homeostasis and collaborating with retinal glial cells to provide metabolic support and ionic buffering. Accordingly, the RPE has recently been shown to display dynamic properties mediated by an array of ion channels usually more characteristic of astrocytes and excitable cells. The recent discovery of canonical voltage-activated Na+ channels in the RPE and their importance for phagocytosis of photoreceptor outer segments raises a question about their electrogenic function. Here, we performed a detailed electrophysiological analysis related to the functioning of these channels in human embryonic stem cell (hESC)-derived RPE. RESULTS: Our studies examining the electrical properties of the hESC-RPE revealed that its membrane mainly displays passive properties in a broad voltage range, with the exception of depolarization-induced spikes caused by voltage-activated Na+ current (INa). Spike amplitude depended on the availability of INa and spike kinetics on the membrane time constant, and the spikes could be largely suppressed by TTX. Membrane resistance fluctuated rapidly and strongly, repeatedly changing over the course of recordings and causing closely correlated fluctuations in resting membrane potential. In a minority of cells, we found delayed secondary INa-like inward currents characterized by comparatively small amplitudes and slow kinetics, which produced secondary depolarizing spikes. Up to three consecutive delayed inward current waves were detected. These currents could be rapidly and reversibly augmented by applying L-type Ca2+ channel blocker nifedipine to diminish influx of calcium and thus increase gap junctional conductance. CONCLUSIONS: This work shows, for the first time, that INa and INa-mediated voltage spikes can spread laterally through gap junctions in the monolayer of cells that are traditionally considered non-excitable. Our findings support a potential role of the RPE that goes beyond giving homeostatic support to the retina.


Assuntos
Retina , Epitélio Pigmentado da Retina , Humanos , Células-Tronco Embrionárias Humanas/fisiologia
19.
Adv Physiol Educ ; 48(2): 356-365, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38482563

RESUMO

Effective communication skills are pivotal in health care, particularly when conveying distressing information to patients and their families. However, medical education still lacks the adoption of a universal model that can be incorporated into the curricula to train and assess students in effectively communicating with patients. This study aims to assess the impact of training undergraduate medical students to deliver bad news effectively using the Empowering Medical students' skills in BReaking bAd news with Compassion and Empathy (EMBRACE) module. This randomized case-control study involved medical students from the first, second, and third professional years (study group, n = 75; control group, n = 75). For the study group, the EMBRACE modules were distributed. Then, a 1-hour training session on effectively delivering bad news was followed by a multiple-choice question test and objective structured clinical examination with response, interpretation, and communication skills stations. Participants' feedback was obtained on a five-point Likert scale. There was a highly significant improvement in knowledge and skills among the study group compared to controls with a P value less than 0.0001. Of the participants, 98.76% perceived that the training equipped them with practical skills, and 98.77% felt that the facilitator had demonstrated the steps of delivering bad news clearly and effectively. Only 4.44% of participants were confident in effectively interacting with patients before the session, and an overwhelming 81.11% gained confidence in their communication skills after the training. With demonstrated significant improvement in knowledge and skills, this study supports the adoption of EMBRACE modules in undergraduate medical education, ultimately improving patient experiences, doctor-patient relationships, and health outcomes.NEW & NOTEWORTHY The Empowering Medical students' skills in BReaking bAd news with Compassion and Empathy (EMBRACE) module is noteworthy for its holistic approach to training medical students in the delicate art of delivering distressing news to patients. It not only incorporates the evidence-based setting, perception, invitation, knowledge, emotions, and strategy (SPIKES) method but also distinguishes itself by providing real-life conversation examples and self-assessment cases, which make the training highly relatable and practical for students to actively engage in their learning and personal development.


Assuntos
Empatia , Estudantes de Medicina , Humanos , Revelação da Verdade , Estudantes de Medicina/psicologia , Estudos de Casos e Controles , Comunicação , Poder Psicológico
20.
BMC Med Educ ; 24(1): 313, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509520

RESUMO

BACKGROUND: The transition of the Accreditation Council for Graduate Medical Education (ACGME) to milestone assessment creates opportunities for collaboration and shared assessments across graduate medical programs. Breaking bad news is an essential communication skill that is a common milestone across almost every medical specialty. The purpose of this study was to develop and pilot an integrated milestone assessment (IMA) tool for breaking bad news using ACGME milestone criteria and to compare the IMA tool with the existing SPIKES protocol. METHODS: The IMA tool was created using sub-anchors in professionalism and interpersonal communication skills that are applicable to every specialty and to the ability to break bad news. Two cases of breaking bad news, designed to be "easy" and "intermediate" in difficulty, were used to assess basic skills in breaking bad news in first-year medical residents from six residency specialties. Eight standardized patients were trained to portray the cases in sessions held in November 2013 and May 2014. Standardized patients completed an assessment checklist to evaluate each resident's performance in breaking bad news based on their use of the SPIKES protocol and IMA tool. Residents answered post-encounter questions about their training and comfort in breaking bad news. The association between SPIKES and IMA scores was investigated by simple linear regression models and Spearman rank correlations. RESULTS: There were 136 eligible medical residents: 108 (79.4%) participated in the first session and 97 (71.3%) participated in the second session, with 96 (70.6%) residents participating in both sessions. Overall, we were able to identify residents that performed at both extremes of the assessment criteria using the integrated milestone assessment (IMA) and the SPIKES protocol. Interestingly, residents rated themselves below "comfortable" on average. CONCLUSION: We developed an integrated milestone assessment (IMA) that was better than the SPIKES protocol at assessing the skill of breaking bad news. This collaborative assessment tool can be used as supplement tool in the era of milestone transformation. We aim assess our tool in other specialties and institutions, as well as assess other shared milestones across specialties.


Assuntos
Internato e Residência , Relações Médico-Paciente , Humanos , Projetos Piloto , Educação de Pós-Graduação em Medicina , Comunicação , Competência Clínica
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