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Objective: Ischemic stroke is one of the main causes of death and disability worldwide and currently has limited treatment options. Electroencephalography (EEG) signals are significantly affected in stroke patients during the acute stage. In this study, we preclinically characterized the brain electrical rhythms and seizure activity during the hyperacute and late acute phases in a hemispheric stroke model with no reperfusion. Methods: EEG signals and seizures were studied in a model of hemispheric infarction induced by permanent occlusion of the middle cerebral artery (pMCAO), which mimics the clinical condition of stroke patients with permanent ischemia. Electrical brain activity was also examined using a photothrombotic (PT) stroke model. In the PT model, we induced a similar (PT group‐1) or smaller (PT group‐2) cortical lesion than in the pMCAO model. For all models, we used a nonconsanguineous mouse strain that mimics human diversity and genetic variation. Results: The pMCAO hemispheric stroke model exhibited thalamic‐origin nonconvulsive seizures during the hyperacute stage that propagated to the thalamus and cortex. The seizures were also accompanied by progressive slowing of the EEG signal during the acute phase, with elevated delta/theta, delta/alpha, and delta/beta ratios. Cortical seizures were also confirmed in the PT stroke model of similar lesions as in the pMCAO model, but not in the PT model of smaller injuries. Significance: In the clinically relevant pMCAO model, poststroke seizures and EEG abnormalities were inferred from recordings of the contralateral hemisphere (noninfarcted hemisphere), emphasizing the reciprocity of interhemispheric connections and that injuries affecting one hemisphere had consequences for the other. Our results recapitulate many of the EEG signal hallmarks seen in stroke patients, thereby validating this specific mouse model for the examination of the mechanistic aspects of brain function and for the exploration of the reversion or suppression of EEG abnormalities in response to neuroprotective and anti‐epileptic therapies. [ABSTRACT FROM AUTHOR]

Structurally patterned pyrolysed three-dimensional carbon scaffolds (p3D-carbon) are fabricated and applied for differentiation of human neural stem cells (hNSCs) developed for cell replacement therapy and sensing of released dopamine. In the absence of differentiation factors (DF) the pyrolysed carbon material induces spontaneous hNSC differentiation into mature dopamine-producing neurons and the 3D-topography promotes neurite elongation. In the presence and absence of DF, ≈73-82% of the hNSCs obtain dopaminergic properties on pyrolysed carbon, a to-date unseen efficiency in both two-dimensional (2D) and 3D environment. Due to conductive properties and 3D environment, the p3D-carbon serves as a neurotransmitter trap, enabling electrochemical detection of a significantly larger dopamine fraction released by the hNSC derived neurons than on conventional 2D electrodes. This is the first study of its kind, presenting new conductive 3D scaffolds that provide highly efficient hNSC differentiation to dopaminergic phenotype combined with real-time in situ confirmation of the fate of the hNSC-derived neurons. [ABSTRACT FROM AUTHOR]