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Rapid increase of BDNF mRNA levels in cortical neurons following spreading depression : regulation by glutamatergic mechanisms independent of seizure activity

Levels of mRNA for nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and the tyrosine kinase receptors trkB and trkC have been studied using in situ hybridization in the rat brain after topical application of KCl to the cortical surface (which induces spreading depression). Repeated episodes of spreading depression during 2 h caused a rapid and marked incre

Coexpression of neurotrophins and their receptors in neurons of the central nervous system

Nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) are neuronal survival molecules which utilize the Trk family of tyrosine kinase receptors. Using double-label in situ hybridization, we demonstrate that mRNAs for BDNF and its high-affinity receptor TrkB are coexpressed in hippocampal and cortical neurons. Also, a large number of neurons in these areas coexpress NGF and BDNF mR

Specific functions of grafted locus coeruleus neurons in the kindling model of epilepsy

Grafts of fetal noradrenaline (NA)-rich locus coeruleus (LC) tissue implanted bilaterally into the hippocampus in 6-hydroxydopamine (6-OHDA) treated, hyperexcitable rats retard seizure development in hippocampal kindling. We report that bilateral intrahippocampal LC grafts failed to affect the severity of seizures when implanted in 6-OHDA-treated, already kindled rats. Furthermore, a noradrenergic

Increased production of the TrkB protein tyrosine kinase receptor after brain insults

The protein-tyrosine kinases Trk, TrkB, and TrkC are signal-transducing receptors for a family of neurotrophic factors known as the neurotrophins. Here we show that seizures induced by hippocampal kindling lead to a rapid, transient increase of trkB mRNA and protein in the hippocampus. TrkB is a component of a high affinity receptor for brain-derived neurotrophic factor (BDNF). No change was detec

Widespread increase of nerve growth factor protein in the rat forebrain after kindling-induced seizures

Nerve growth factor (NGF) protein levels were determined in various forebrain regions using a two-site immunoassay following kindling-induced seizures. In the dentate gyrus the NGF content was significantly elevated 7 days after the last seizure (to 152% of control). In the piriform and parietal cortices, maximal increases were seen at 12 h (to 261% of control) and at 24 h (to 169% of control), re

Polarization transfer in the 16O(\vec{e},e′\vec{p})15N reaction

The first (→e,e′→p) polarization transfer measurements on a nucleus heavier than deuterium have been carried out at Jefferson Laboratory. Transverse and longitudinal components of the polarization of protons ejected in the reaction 16O(→e,e′→p) were measured in quasielastic perpendicular kinematics at a Q2 of 0.8 (GeV/c)2. The data are in good agreement with state of the art calculations.

Regional Forebrain Noradrenalin Release in Response to Focal and Generalized Seizures Induced by Hippocampal Kindling Stimulation

In vivo microdialysis was used to monitor noradrenalin (NA) release in the rat hippocampus, sensorimotor cortex and amygdala in response to seizures induced by electrical kindling stimulation in the hippocampus. Generalized seizures increased NA output in the hippocampus five-fold above baseline level (as assessed with 2-min sampling periods). The peak value was seen 2 - 4 min after onset of seizu

Dynamical Relativistic Effects in Quasielastic 1p-Shell Proton Knockout from 16O

We have measured the cross section for quasielastic 1p-shell proton knockout in the 16O(e,e′p) reaction at ω=0.439GeV and Q2=0.8(GeV/c)2 for missing momentum Pmiss≤355MeV/c. We have extracted the response functions RL+TT, RT, RLT, and the left-right asymmetry, ALT, for the 1p1/2 and the 1p3/2 states. The data are well described by relativistic distorted wave impulse approximation calculations. At

GEp/GMp Ratio by Polarization Transfer in \vec{e}p→e\vec{p}

The ratio of the proton's elastic electromagnetic form factors, GEp/GMp, was obtained by measuring Pt and Pℓ, the transverse and the longitudinal recoil proton polarization, respectively. For elastic →ep→e→p, GEp/GMp is proportional to Pt/Pℓ. Simultaneous measurement of Pt and Pℓ in a polarimeter provides good control of the systematic uncertainty. The results for the ratio GEp/GMp show a systemat

Measurements of the Deuteron Elastic Structure Function A(Q2) for 0.7≤Q2≤6.0(GeV/c)2 at Jefferson Laboratory

The deuteron elastic structure function A(Q2) has been extracted in the range 0.7≤Q2≤6.0(GeV/c)2 from cross section measurements of elastic electron-deuteron scattering in coincidence using the Hall A Facility of Jefferson Laboratory. The data are compared to theoretical models, based on the impulse approximation with the inclusion of meson-exchange currents, and to predictions of quark dimensiona

Part summary of the project 'Speakers' Comfort' : Teachers' voice use in teaching environments

Classroom acoustics not always take the speaker's comfort into consideration. The purpose of the presented papers was to investigate voice use, vocal behavior and prevalence of voice problems in Swedish teaching staff. Ratings of features in the work-environment on voice use were explored in n = 487 teachers. Based on their answers the respondents were split into two groups: teachers with self-ass

Measurement of the neutral weak form factors of the proton

We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from the proton. The kinematic point [ ⟨θlab⟩=12.3° and ⟨Q2⟩=0.48(GeV/c)2] is chosen to provide sensitivity, at a level that is of theoretical interest, to the strange electric form factor GsE. The result, A=−14.5±2.2ppm, is consistent with the electroweak standard model and no additional c