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BACKGROUND AND PURPOSE: The KCNQ2 gene encodes for the K(v) 7.2 subunit of non-inactivating potassium channels. KCNQ2-related diseases range from autosomal dominant neonatal self-limited epilepsy, often caused by KCNQ2 haploinsufficiency, to severe encephalopathies caused by KCNQ2 missense variants. In vivo and in vitro effects of the sodium channel blocker eslicarbazepine acetate (ESL) and eslicarbazepine metabolite (S-Lic) in a mouse model of self-limited neonatal epilepsy as a first attempt to assess the utility of ESL in the KCNQ2 disease spectrum was investigated. EXPERIMENTAL APPROACH: Effects of S-Lic on in vitro physiological and pathological hippocampal neuronal activity in slices from mice carrying a heterozygous deletion of Kcnq2 (Kcnq2(+/-)) and Kcnq2(+/+) mice were investigated. ESL in vivo efficacy was investigated in the 6-Hz psychomotor seizure model in both Kcnq2(+/-) and Kcnq2(+/+) mice. KEY RESULTS: S-Lic increased the amplitude and decreased the incidence of physiological sharp wave-ripples in a concentration-dependent manner and slightly decreased gamma oscillations frequency. 4-Aminopyridine-evoked seizure-like events were blocked at high S-Lic concentrations and substantially reduced in incidence at lower concentrations. These results were not different in Kcnq2(+/+) and Kcnq2(+/-) mice, although the EC(50) estimation implicated higher efficacy in Kcnq2(+/-) animals. In vivo, Kcnq2(+/-) mice had a lower seizure threshold than Kcnq2+/+ mice. In both genotypes, ESL dose-dependently displayed protection against seizures. CONCLUSIONS AND IMPLICATIONS: S-Lic slightly modulates hippocampal oscillations and blocks epileptic activity in vitro and in vivo. Our results suggest that the increased excitability in Kcnq2(+/-) mice is effectively targeted by S-Lic high concentrations, presumably by blocking diverse sodium channel subtypes.

The role of mossy cells (MCs) of the hippocampal dentate area has long remained mysterious. Recent research has begun to unveil their significance in spatial computation of the hippocampus. Here, we used an in vitro model of sharp wave-ripple complexes (SWRs), which contribute to hippocampal memory formation, to investigate MC involvement in this fundamental population activity. We find that a significant fraction of MCs (~47%) is recruited into the active neuronal network during SWRs in the CA3 area. Moreover, MCs receive pronounced, ripple-coherent, excitatory and inhibitory synaptic input. Finally, we find evidence for SWR-related synaptic activity in granule cells that is mediated by MCs. Given the widespread connectivity of MCs within and between hippocampi, our data suggest a role for MCs as a hub functionally coupling the CA3 and the DG during ripple-associated computations.

The 850 hPa air pressure level is situated about 1.5 km above sea level. This means that the surface does not influence the temperature at this altitude, so the diurnal temperature variations are small. They are about 2-3 degrees, or they do not exist, at all. This is why temperature of the 850 hPa level is used for identification of air masses and location of warm and cold fronts. Moreover, temperature variation of the 850 hPa level can be analysed in themselves, as indicators of climate 1500 meters above the sea level. The 1973-2014 period, analysed in this study, was chosen as the longest available series in Cluj-Napoca. The results, concerning the evolution of temperature at this standard isobaric level pointed at strong warming in the last 10-15 years. In the last 7 years the highest temperatures were higher by one degree at the 850 hPa lever than in the preceding years. The heating at the analyzed isobaric level overlaps the growing of ground temperature, analyzed the medium annual temperature in the period 1973-2014.

We have realized a (GaAs1-xSbx-InyGa1-yAs)/GaAs bilayer-quantum well (BQW), which consists of two adjacent pseudomorphic layers of GaAs1-xSbx and InyGa1-yAs sandwiched between GaAs barriers. Photoluminescence was observed at longer wavelengths than those found for corresponding InyGa1-yAs/GaAs and GaAs1-xSbx/GaAs single quantum wells (SQW), which indicates a type-II band alignment in the BQW. The longest 300 K emission wavelength achieved so far was 1.332 mu m. For an accurate determination of the band offset between GaAs1-xSbx and GaAs, required for a theoretical modeling of the interband transition energies of these BQWs, a large set of GaAs1-xSbx/GaAs SQWs was prepared from which a type-II band alignment was deduced, with the valence band discontinuity ratio Qupsilon found to depend on the Sb concentration x (Qupsilon =1.76+1.34 x). With this parameter it was possible to calculate the expected interband transition energies in a BQW structure without any adjustable parameters. The ca lculations are in agreement with experimental data within a range of +or-4%.