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Cerium oxide (CeO2) is a material with unique dielectric properties that make it a promising candidate for various applications. High electrical resistance and a wide bandgap of pristine CeO2 limit its applicability in photovoltaics and photo‐electrocatalysis. CeO2 is co‐doped with transition metals (Fe+2/Fe+3 and Cu+2), which reduces its optical bandgap energy and electrical resistance. This study aims to investigate the dielectric relaxation behavior and charge‐carrier dynamics of Fe, Cu–CeO2. The enhanced charge‐carrier dynamics in the Fe, Cu–doped CeO2 compared to pristine CeO2 are reported. Using temperature‐dependent electrochemical impedance spectroscopy (TD‐EIS), the dielectric relaxation and carrier dynamics in pristine CeO2 and Fe, Cu–doped CeO2 in the temperature range 313–473 K along with the modulus spectroscopy are investigated. It is observed that Z′ values reduced with the temperature, thus showing the negative temperature coefficient of resistance in the frequency range 6.28–1.005 × 105 radians s−1. Furthermore, a correlated study of –Z″ and M″ shows the charge‐carrier relaxation behavior changes from ideal Debye type to non‐Debye type with temperature rise in Fe, Cu–doped CeO2. [ABSTRACT FROM AUTHOR]

Aim: We performed a systematic review and network meta-analysis (NMA) to obtain comparative effectiveness estimates and rankings of non-surgical interventions used to treat infantile spasms.Method: All randomized controlled trials (RCTs) including children 2 months to 3 years of age with infantile spasms (with hypsarrhythmia or hypsarrhythmia variants on electroencephalography) receiving appropriate first-line medical treatment were included. Electroclinical and clinical remissions within 1 month of starting treatment were analyzed.Results: Twenty-two RCTs comparing first-line treatments for infantile spasms were reviewed; of these, 17 were included in the NMA. Both frequentist and Bayesian network rankings for electroclinical remission showed that high dose adrenocorticotropic hormone (ACTH), methylprednisolone, low dose ACTH and magnesium sulfate (MgSO4 ) combination, low dose ACTH, and high dose prednisolone were most likely to be the 'best' interventions, although these were not significantly different from each other. For clinical remission, low dose ACTH/MgSO4 combination, high dose ACTH (with/without vitamin B6 ), high dose prednisolone, and low dose ACTH were 'best'.Interpretation: Treatments including ACTH and high dose prednisolone are more effective in achieving electroclinical and clinical remissions for infantile spasms.What This Paper Adds: Adrenocorticotropic hormone and high dose prednisolone are more effective than other medications for infantile spasms. Symptomatic etiology decreases the likelihood of remission even after adjusting for treatment lag. [ABSTRACT FROM AUTHOR]

Aim: To determine whether epilepsy surgery improved health-related quality of life (HRQoL) and whether seizure freedom after surgery mediated the improvement in HRQoL.Method: This multicenter cohort study compared HRQoL after epilepsy surgery to pharmacological management in children with drug-resistant epilepsy (DRE). HRQoL was measured using the Quality of Life in Childhood Epilepsy (QOLCE) questionnaire at baseline and 1-year follow-up. The mediator between treatment type and HRQoL was seizure freedom.Results: Two hundred and thirty-seven patients were recruited (surgery group: n=147 [92 males, 45 females]; pharmacological group: n=90 [53 males, 37 females]). Mean age at seizure onset was 6 years (SD 4y 4mo) in the surgical group and 6 years 1 month (SD 4y) in the pharmacological group. The odds ratio of seizure freedom was higher for the surgery versus pharmacological group (β=4.24 [95% confidence interval {CI}: 2.26-7.93], p<0.001). Surgery had no direct effect on total QOLCE score at 1-year (β=0.24 [95% CI -2.04 to 2.51], p=0.839) compared to pharmacological management, but had an indirect effect on total QOLCE that was mediated by seizure freedom (β=0.92 [95% CI 0.19-1.65], p=0.013), adjusting for baseline total QOLCE score. Surgery had a direct effect on improving social function (p=0.043), and an indirect effect on improving physical function (p=0.016), cognition (p=0.042), social function (p=0.012) and behavior (p=0.032), mediated by seizure freedom.Interpretation: Greater seizure freedom achieved through epilepsy surgery mediated the improvement in HRQoL compared to pharmacological management in children with DRE.What This Paper Adds: Seizure freedom is higher after pediatric epilepsy surgery compared to pharmacologically managed epilepsy. Surgery indirectly improves health-related quality of life (HRQoL) mediated by seizure freedom compared to pharmacological management. Surgery has a direct effect on improving social function relative to pharmacological management. Baseline HRQoL was an important predictor of HRQoL after treatment. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) is a highly stable, photosensitive, and nontoxic metal oxide. The physical and chemical properties of TiO2 electrodes have been explored extensively for the last few decades. However, a detailed and comparative study of the dielectric relaxation and carrier kinetics with the dopants is still lacking. Herein, the crystallinity of TiO2 electrodes decreased with the dopants is reported. The doping of copper (Cu) in TiO2 reduces its bandgap to 2.98 eV from 3.22 eV. The improved charge carrier conduction at high frequencies (ω = 103–106 radians s−1) with the doping is noticed. The charge transfer resistance (Rct) for the electrons is minimum for Cu–TiO2 (Rct = 34.11 Ω) and Cu, Zn, and N–TiO2 (Rct = 27.44 Ω) compared to pristine and Cu and Zn–TiO2. Further, the high electrical permittivity is associated with the polar nature of electrodes. The correlation analysis of impedance and modulus spectroscopy data provides a prodigious picture of the charge carrier relaxation and conduction mechanism. A shift in the dielectric relaxation process from Debye type to non‐Debye type is observed after doping due to defect‐mediated fast relaxation of polarization. [ABSTRACT FROM AUTHOR]

Outcomes following vagus nerve stimulation (VNS) improve over years after implantation in children with drug‐resistant epilepsy. The added value of deep brain stimulation (DBS) instead of continued VNS optimization is unknown. In a prospective, non‐blinded, randomized patient preference trial of 18 children (aged 8–17 years) who did not respond to VNS after at least 1 year, add‐on DBS resulted in greater seizure reduction compared with an additional year of VNS optimization (51.9% vs. 12.3%, p = 0.047). Add‐on DBS also resulted in less bothersome seizures (p = 0.03), but no change in quality of life. DBS may be considered earlier for childhood epilepsy after non‐response to VNS. ANN NEUROL 2024 [ABSTRACT FROM AUTHOR]

In article number 2200807 by Manish Kumar Vishwakarma, Monojit Bag, and Puneet Jain, the correlation analysis of impedance and modulus spectroscopy data paints a detailed picture of the charge carrier relaxation and conduction mechanism. B TiO SB 2 sb -Based Materials b The incorporation of both metallic and non-metallic ions into TiO SB 2 sb has emerged as a promising area of research, as it has the potential to enhance the charge carrier kinetics. [Extracted from the article]

Children with epilepsy commonly have comorbid neurocognitive impairments that severely affect their psychosocial well‐being, education, and future career prospects. Although the provenance of these deficits is multifactorial, the effects of interictal epileptiform discharges (IEDs) and anti‐seizure medications (ASMs) are thought to be particularly severe. Although certain ASMs can be leveraged to inhibit IED occurrence, it remains unclear whether epileptiform discharges or the medications themselves are most deleterious to cognition. To examine this question, 25 children undergoing invasive monitoring for refractory focal epilepsy performed one or more sessions of a cognitive flexibility task. Electrophysiological data were recorded to detect IEDs. Between repeated sessions, prescribed ASMs were either continued or titrated to <50% of the baseline dose. Hierarchical mixed‐effects modeling assessed the relationship between task reaction time (RT), IED occurrence, ASM type, and dose while controlling for seizure frequency. Both presence (β ± SE = 49.91 ± 16.55 ms, p =.003) and number of IEDs (β ± SE = 49.84 ± 12.51 ms, p <.001) were associated with slowed task RT. Higher dose oxcarbazepine significantly reduced IED frequency (p =.009) and improved task performance (β ± SE = −107.43 ± 39.54 ms, p =.007). These results emphasize the neurocognitive consequences of IEDs independent of seizure effects. Furthermore, we demonstrate that inhibition of IEDs following treatment with select ASMs is associated with improved neurocognitive function. [ABSTRACT FROM AUTHOR]

Objective: The theory of transient cognitive impairment in epilepsy posits that lapses in attention result from ephemeral disruption of attentional circuitry by interictal events. Eye movements are intimately associated with human attention and can be monitored in real time using eye‐tracking technologies. Here, we sought to characterize the associations between interictal epileptiform discharges (IEDs), gaze, and attentional behavior in children with epilepsy. Methods: Eleven consecutive children undergoing invasive monitoring with stereotactic electrodes for localization‐related epilepsy performed an attentional set‐shifting task while tandem intracranial electroencephalographic signals and eye‐tracking data were recorded. Using an established algorithm, IEDs were detected across all intracranial electrodes on a trial‐by‐trial basis. Hierarchical mixed‐effects modeling was performed to delineate associations between trial reaction time (RT), eye movements, and IEDs. Results: Hierarchical mixed‐effects modeling revealed that both the presence of an IED (β ± SE = 72.74 ± 24.21 ms, p =.003) and the frequency of epileptiform events (β ± SE = 67.54 ± 17.30 ms, p <.001) were associated with prolonged RT on the attentional set‐shifting task. IED occurrence at the time of stimulus presentation was associated with delays in gaze initiation toward the visual targets (p =.017). Significance: The occurrence of epileptiform activity in close temporal association with stimulus presentation is associated with delays in target‐directed gaze and prolonged response time, hallmarks of momentary lapses in attention. These findings provide novel insights into the mechanisms of transient impairments in children and support the use of visual tracking as a correlate of higher order attentional behavior. [ABSTRACT FROM AUTHOR]

Objective: Working memory deficits are prevalent in childhood epilepsy. Working memory processing is thought to be supported by the phase of hippocampal neural oscillations. Disruptions in working memory have previously been linked to the occurrence of transient epileptic activity. This study aimed to resolve the associations between oscillatory neural activity, transient epileptiform events, and working memory in children with epilepsy. Methods: Intracranial recordings were acquired from stereotactically implanted electrodes in the hippocampi, epileptogenic zones, and working memory‐related networks of children with drug‐resistant epilepsy during a 1‐back working memory task. Interictal epileptic activity was captured using automated detectors. Hippocampal phase and interregional connectivity within working memory networks were indexed by Rayleigh Z and the phase difference derivative, respectively. Trials with and without transient epileptiform events were compared. Results: Twelve children (mean age = 14.3 ± 2.8 years) with drug‐resistant epilepsy were included in the study. In the absence of transient epileptic activity, significant delta and theta hippocampal phase resetting occurred in response to working memory stimulus presentation (Rayleigh z‐score = 9, Rayleigh z‐score = 8). Retrieval trials that were in phase with the preferred phase angle were associated with faster reaction times (p =.01, p =.03). Concurrently, delta and theta coordinated interactions between the hippocampi and working memory‐related networks were enhanced (phase difference derivative [PDD] z‐scores = 6–11). During retrieval trials with pre‐encoding or pre‐retrieval transient epileptic activity, phase resetting was attenuated (Rayleigh z‐score = 5, Rayleigh z‐score = 1), interregional connectivity was altered (PDD z‐scores = 1–3), and reaction times were prolonged (p =.01, p =.03). Significance: This work highlights the role of hippocampal phase in working memory. We observe poststimulus hippocampal phase resetting coincident with enhanced interregional connectivity. The precision of hippocampal phase predicts optimal working memory processing, and transient epileptic activity prolongs working memory processing. These findings can help guide future treatments aimed at restoring memory function in this patient population. [ABSTRACT FROM AUTHOR]

Objective: Through international collaboration, we evaluated the phenotypic aspects of a multiethnic cohort of KCNT1‐related epilepsy and explored genotype‐phenotype correlations associated with frequently encountered variants. Methods: A cross‐sectional analysis of children harboring pathogenic or likely pathogenic KCNT1 variants was completed. Children with one of the two more common recurrent KCNT1 variants were compared with the rest of the cohort for the presence of particular characteristics. Results: Twenty‐seven children (15 males, mean age = 40.8 months) were included. Seizure onset ranged from 1 day to 6 months, and half (48.1%) exhibited developmental plateauing upon onset. Two‐thirds had epilepsy of infancy with migrating focal seizures (EIMFS), and focal tonic seizures were common (48.1%). The most frequent recurrent KCNT1 variants were c.2800G>A; p.Ala934Thr (n = 5) and c.862G>A; p.Gly288Ser (n = 4). De novo variants were found in 96% of tested parents (23/24). Sixty percent had abnormal magnetic resonance imaging (MRI) findings. Delayed myelination, thin corpus callosum, and brain atrophy were the most common. One child had gray‐white matter interface indistinctness, suggesting a malformation of cortical development. Several antiepileptic drugs (mean = 7.4/patient) were tried, with no consistent response to any one agent. Eleven tried quinidine; 45% had marked (>50% seizure reduction) or some improvement (25%‐50% seizure reduction). Seven used cannabidiol; 71% experienced marked or some improvement. Fourteen tried diet therapies; 57% had marked or some improvement. When comparing the recurrent variants to the rest of the cohort with respect to developmental trajectory, presence of EIMFS, >500 seizures/mo, abnormal MRI, and treatment response, there were no statistically significant differences. Four patients died (15%), none of sudden unexpected death in epilepsy. Significance: Our cohort reinforces common aspects of this highly pleiotropic entity. EIMFS manifesting with refractory tonic seizures was the most common. Cannabidiol, diet therapy, and quinidine seem to offer the best chances of seizure reduction, although evidence‐based practice is still unavailable. [ABSTRACT FROM AUTHOR]

Summary: Objective: Polymicrogyria (PMG) is a common malformation of cortical development. Many patients with PMG will have medically refractory epilepsy but the role of epilepsy surgery is unclear. The objective of this study was to assess the efficacy of surgical resection/disconnection in achieving seizure control in pediatric patients with PMG. Methods: A retrospective review of children undergoing epilepsy surgery for PMG between 2002 and 2017 at The Hospital for Sick Children in Toronto, Canada, was performed. Results: A total of 12 children aged 6 months to 17.8 years (median 8.8 years) underwent resective surgery (7 children) or functional hemispherectomy (5 children). Gross total resection or complete disconnection of PMG was carried out in 7 of 12 children. Follow‐up duration was between 1 and 9 years (median 2.1 years). Nine children remained seizure‐free at last follow‐up. Complete resection or disconnection of PMG led to seizure freedom in 6 of 7 patients (86%), whereas subtotal resection produced seizure freedom in 3 of 5 patients (60%). Significance: We present one of the largest surgical series of pediatric PMG patients. Seizure outcomes were best with complete resection/disconnection of PMG. However, tailored resections based on electroclinical and neuroradiologic data can produce good outcomes and remain an appropriate strategy for patients with extensive PMG. [ABSTRACT FROM AUTHOR]

ABSTRACT Background SLC30A10 mutations cause an autosomal recessive disorder, characterized by hypermanganesaemia, polycythemia, early-onset dystonia, paraparesis, or late-onset parkinsonism, and chronic liver disease. This is the first identified inborn error of Mn metabolism in humans, reported in 10 families thus far. Methods Methods for this study consisted of clinical examination, neuroimaging studies (MRI), serum dosages, and SLC30A10 genetic analysis. Results We describe early disease manifestations (including videos) in 5 previously unreported Indian children, carrying novel homozygous SLC30A10 mutations. Gait and speech disturbances, falls, dystonias, and central hypotonia were the presenting neurological features, starting within the first 5 years of life. All children also had severe hypermanganesemia, polycythemia, variable degree of liver disease, and marked brain MRI T1 hyperintensities. Conclusions Our findings expand the mutational and clinical spectra of this recently recognized disorder. An early diagnosis is warranted, because treatment with manganese-chelating agents, iron supplementation, or their combination might improve symptoms and prevent progression of this otherwise potentially fatal disease. © 2015 International Parkinson and Movement Disorder Society [ABSTRACT FROM AUTHOR]