Summary:Purpose: Several animal studies suggest that the thalamus might be involved in the maintenance and propagation of epileptic seizures. However, electrophysiologic evidence for this implication in human partial epileptic seizures is still lacking. Considering the rich and reciprocal connectivity of the medial pulvinar (PuM) with the temporal lobe, we evaluated a potential participation of this thalamic nucleus in temporal lobe epilepsy (TLE).Methods: The electrophysiologic activity of PuM was recorded during stereoelectroencephalographic exploration of spontaneous temporal lobe seizures in 14 patients referred for presurgical assessment of refractory TLE.Results: We recorded PuM ictal activity in 80% of the 74 seizures that we analyzed. This activity was characterized by rhythmic slow-waves or rhythmic spikes (RSW-RS) or both or by low-voltage fast activity (LVFA) in 64% and 36% of seizures, respectively. RSW-RS occurred mostly in seizures arising from mesiotemporal structures, whereas LVFA was more frequently observed in seizures of neocortical origin. In the 15 seizures without PuM ictal activity, spreading of the seizure outside the onset zone never occurred, whereas it did in 78% of seizures with PuM ictal involvement. Discharge propagation was systematic when PuM involvement corresponded to LVFA, whatever the seizure onset zone was, whereas it represented only 66% of the seizures when PuM exhibited RSW-RS.Conclusions: This study shows that ictal changes in PuM activity are frequently observed during temporal lobe seizures and suggests that this thalamic nucleus might participate in their propagation.

The thalamic medial pulvinar nucleus (PuM) is fully developed only in primates and reaches its greatest extent in humans. To assess the reciprocal functional connectivity between PuM and cortex, we studied intracerebral-evoked responses obtained after PuM and cortical electrical stimulation in 7 epileptic patients undergoing depth electroencephalographic recordings. Cortical-evoked potentials (CEPs) to PuM stimulation were recorded from all explored cortical regions, except striate cortex, anterior cingulated, and postcentral gyrus. Percentages of cortical contacts pairs responding to PuM stimulation (CEPs response rate) ranged from 80% in temporal neocortex, temporoparietal (TP) junction, insula, and frontoparietal opercular cortex to 34% in mesial temporal regions. Reciprocally, PuM-evoked potentials (PEPs) response rates were 14% after cortical stimulation in insula and frontoparietal opercular cortex, 67% in the TP junction, 76% in temporal neocortex, and 80% in mesial temporal regions. Overall, our study of functional PuM connectivity in the human brain converges with most of the data from anatomical studies in monkeys, except for a strong amygdalohippocampal functional projection to PuM and an unexpected imbalance between some of the reciprocal pathways explored. This functional quantitative approach helps to clarify the functional role of PuM as well as its implication in temporal lobe epileptic seizures.

Redox‐Flow‐Batterien auf Basis von Vanadium‐Verbindungen werden derzeit als Energiespeicher erprobt, um im Rahmen des Ausbaus der erneuerbaren Energien entstehende Einspeisespitzen und Nachfrageschwankungen zu kompensieren. Vanadium‐Verbindungen sind aufgrund ihrer Toxizität für den Chemieunterricht nicht geeignet. Um dieses Thema für den Chemieunterricht zur erschließen, werden in Anlehnung an die Arbeiten der Arbeitsgruppen um Aziz und Narayanan Experimente unter Verwendung von Hydrochinonen und Chinonen entwickelt. In diesem Artikel werden grundlegende Versuche, in denen auf die Arbeiten von Aziz und Narayanan eingegangen wird, präsentiert sowie organische Batterien unter der Verwendung von Alltagsmaterialien vorgestellt.