Frequently, SPWs are generated in bursts or clusters of several consecutive events forming discrete episodes of activity, a hitherto unexplored feature of this prominent hippocampal network activity. In the present study, using rat ventral hippocampal slices, we show that clusters of SPWs consist

of two to four consecutive events occurring at a frequency of similar to 10 Hz (range, 7-14 Hz). Similarly to the first (primary) event in a cluster the following (secondary) SPWs correspond to inhibitory postsynaptic potentials in CA1 pyramidal cells. Furthermore, the initiation of secondary SPWs in the 23% of cells coincides with postinhibitory rebound excitation. Antagonists of NMDA receptors reversibly abolish secondary but not primary SPWs suggesting that their generation depend on the activation of NMDA receptors. Furthermore, the generation of clusters of selleck products SPWs is very sensitive to moderate

pharmacological reduction or enhancement of the GABA (A) receptor-mediated transmission suggesting that precise levels of GABAergic transmission are required MS-275 in vitro for the clustered generation of SPWs. In addition, enhancement of GABA (A) receptor-mediated transmission affects the timing of secondary SPWs initiation. Trains of high-frequency (100 Hz) or theta burst stimulation at the Schaffer collaterals that induce long-term potentiation of the evoked field response enhance the incidence of SPWs’ clusters and the amplitude of the primary SPWs. We propose that sequential similar to 10 Hz clustered activation of the

local hippocampal circuit occurring under the dynamics of SPWs and depending on NMDA receptors Thiamine-diphosphate kinase and an accurate level of GABAergic synaptic transmission is an essential pattern of precisely controlled network activity involved in synaptic plasticity processes with potential implications in mnemonic functions. (C) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.”
“A pandemic caused by a novel influenza A virus (H1N1) poses a serious public health threat. In this study, a real-time reverse transcriptase PCR (RT-PCR) assay based on the hemagglutinin gene was developed that discriminates the novel H1N1 from swine influenza virus, seasonal H1N1/H3N2 virus and the highly pathogenic H5N1 avian influenza virus. The sensitivity of this assay was 0.2 50% tissue culture infective dose of virus and 200 copies of in vitro-transcribed target RNA. Three hundred and forty-eight clinical specimens from suspected H1N1 patients were tested using this assay, and forty-two (12.07%) were found to be positive. Tests using the real-time PCR assay recommended by WHO and virus isolation gave identical results. This sensitive and specific real-time RT-PCR assay will contribute to the early diagnosis and control of the emerging H1N1 influenza pandemic. (C) 2009 Elsevier B.V. All rights reserved.”
“Prolonged seizures (status epilepticus) can activate apoptosis-associated signaling pathways.