Search results for "neuron"

Long-range intralaminar noise correlations in the barrel cortex

2015

Identifying the properties of correlations in the firing of neocortical neurons is central to our understanding of cortical information processing. It has been generally assumed, by virtue of the columnar organization of the neocortex, that the firing of neurons residing in a certain vertical domain is highly correlated. On the other hand, firing correlations between neurons steeply decline with horizontal distance. Technical difficulties in sampling neurons with sufficient spatial information have precluded the critical evaluation of these notions. We used 128-channel “silicon probes” to examine the spike-count noise correlations during spontaneous activity between multiple neurons with i…

Neurovascular EGFL7 regulates adult neurogenesis in the subventricular zone and thereby affects olfactory perception

2016

Adult neural stem cells reside in a specialized niche in the subventricular zone (SVZ). Throughout life they give rise to adult-born neurons in the olfactory bulb (OB), thus contributing to neural plasticity and pattern discrimination. Here, we show that the neurovascular protein EGFL7 is secreted by endothelial cells and neural stem cells (NSCs) of the SVZ to shape the vascular stem-cell niche. Loss of EGFL7 causes an accumulation of activated NSCs, which display enhanced activity and re-entry into the cell cycle. EGFL7 pushes activated NSCs towards quiescence and neuronal progeny towards differentiation. This is achieved by promoting Dll4-induced Notch signalling at the blood vessel-stem …

Macrophage migration inhibitory factor is critically involved in basal and fluoxetine-stimulated adult hippocampal cell proliferation and in anxiety,…

2011

Intensive research is devoted to unravel the neurobiological mechanisms mediating adult hippocampal neurogenesis, its regulation by antidepressants, and its behavioral consequences. Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine that is expressed in the CNS, where its function is unknown. Here, we show, for the first time, the relevance of MIF expression for adult hippocampal neurogenesis. We identify MIF expression in neurogenic cells (in stem cells, cells undergoing proliferation, and in newly proliferated cells undergoing maturation) in the subgranular zone of the rodent dentate gyrus. A causal function for MIF in cell proliferation was shown using genetic (M…

Fasciola spp: Mapping of the MF6 epitope and antigenic analysis of the MF6p/HDM family of heme-binding proteins

2017

MF6p/FhHDM-1 is a small cationic heme-binding protein which is recognized by the monoclonal antibody (mAb) MF6, and abundantly present in parenchymal cells and secreted antigens of Fasciola hepatica. Orthologs of this protein (MF6p/HDMs) also exist in other causal agents of important foodborne trematodiasis, such as Clonorchis sinensis, Opisthorchis viverrini and Paragonimus westermani. Considering that MF6p/FhHDM-1 is relevant for heme homeostasis in Fasciola and was reported to have immunomodulatory properties, this protein is expected to be a useful target for vaccination. Thus, in this study we mapped the epitope recognized by mAb MF6 and evaluated its antigenicity in sheep. The sequenc…

Image-guided transcranial Doppler sonography for monitoring of vasospasm after subarachnoid hemorrhage.

2016

Transcranial Doppler ultrasound (TCD) is a standard method for bedside vasospasm monitoring after subarachnoid hemorrhage (SAH). Image guidance has previously been shown to reduce intra- and interobserver variability of this method. The aim of the present study was to compare image-guided and conventional TCD in vasospasm monitoring after SAH.418 TCD exams of 24 consecutive SAH patients registered in a database were evaluated. Of these, 130 image-guided exams were identified which had been performed on the same day as conventional Doppler exams. These matched pairs were taken for statistical analysis. Data were tested statistically using the sign test applied at patient level to aggregated …

PSA-NCAM is expressed in immature, but not recently generated, neurons in the adult cat cerebral cortex layer II

2011

Neuronal production persists during adulthood in the dentate gyrus and the olfactory bulb, where substantial numbers of immature neurons can be found. These cells can also be found in the paleocortex layer II of adult rodents, but in this case most of them have been generated during embryogenesis. Recent reports have described the presence of similar cells, with a wider distribution, in the cerebral cortex of adult cats and primates and have suggested that they may develop into interneurons. The objective of this study is to verify this hypothesis and to explore the origin of these immature neurons in adult cats. We have analyzed their distribution using immunohistochemical analysis of the …

Nitric oxide modulates striatal neuronal activity via soluble guanylyl cyclase: an in vivo microiontophoretic study in rats.

2003

It is now well established that nitric oxide (NO) acts as a neuromodulator in the central nervous system. To assess the role of NO in modulating striatal activity, single-unit recording was combined with iontophoresis to study presumed spiny projection neurons in urethane-anesthetized male rats. Striatal neurons recorded were essentially quiescent and were therefore activated to fire by the iontophoretic administration of glutamate, pulsed in cycles of 30 sec on and 40 sec off. In this study, iontophoresis of 3-morpholinosydnonimine hydrochloride (SIN 1), a nitric oxide donor, produced reproducible, current-dependent inhibition of glutamate-induced excitation in 12 of 15 striatal neurons, r…

Isomorphism and Mirror Neurons

2007

This paper aims to give a constructive contribution to Eagle & Wakefield's con-tention ( Gestalt Theory 29, 59-64) that the Gestaltists' hypotheses regarding isomorphism andphenomenological direct access to other's mind anticipate recent accounts of mind-readingability. I attempt to specify the extent to which Gestalt psychology might be seen to be consistentunder certain respects with mirror neurons system theory and embodied simulation theory,claimed to be founding the aforementioned ability. Therefore, empirical and theoretical issues such as the neurobiological features of the mirrorneuron system, the psychological explanation of its functions, and the features of the embodied simulatio…

NEURONS AND ASTROCYTES SHED EXTRACELLULAR VESICLES THAT SEEM TO VEHICLE ANGIOGENIC FACTORS

2007

Characterization of rat glutathione transferases in olfactory epithelium and mucus

2019

International audience; The olfactory epithelium is continuously exposed to exogenous chemicals, including odorants. During the past decade, the enzymes surrounding the olfactory receptors have been shown to make an important contribution to the process of olfaction. Mammalian xenobiotic metabolizing enzymes, such as cytochrome P450, esterases and glutathione transferases (GSTs), have been shown to participate in odorant clearance from the olfactory receptor environment, consequently contributing to the maintenance of sensitivity toward odorants. GSTs have previously been shown to be involved in numerous physiological processes, including detoxification, steroid hormone biosynthesis, and am…