Search results for "neuron"
showing 10 items of 2611 documents
Different α2δ Accessory Subunits Regulate Distinctly Different Aspects of Calcium Channel Function in the Same Drosophila Neurons
2019
AbstractVoltage gated calcium channels (VGCCs) regulate neuronal excitability and translate activity into calcium dependent intracellular signaling. The pore forming α1subunit of high voltage activated (HVA) VGCCs operates not in isolation but associates with α2δ accessory subunits. α2δ subunits can affect calcium channel biophysical properties, surfacing, localization and transport, but theirin vivofunctions are incompletely understood. In vertebrates, it is largely unknown whether different combinations of the four α2δ and the 7 α1subunits mediate different or partially redundant functions or whether different α1/α2δ combinations regulate different aspects of VGCC function. This study cap…
Emerging Therapeutic Strategies for Traumatic Spinal Cord Injury
2020
Spinal cord injury (SCI) is a debilitating neurologic condition with tremendous socioeconomic impact on affected individuals and the health care system. The treatment of SCI principally includes surgical treatment and marginal pharmacologic and rehabilitation therapies targeting secondary events with minor clinical improvements. This unsuccessful result mainly reflects the complexity of SCI pathophysiology and the diverse biochemical and physiologic changes that occur in the injured spinal cord. Once the nervous system is injured, cascades of cellular and molecular events are triggered at varying times. Although the cascade of tissue reactions and cell injury develops over a period of days …
Genetic relationship between five psychiatric disorders estimated from genome-wide SNPs
2013
AM Vicente - Cross-Disorder Group of the Psychiatric Genomics Consortium Most psychiatric disorders are moderately to highly heritable. The degree to which genetic variation is unique to individual disorders or shared across disorders is unclear. To examine shared genetic etiology, we use genome-wide genotype data from the Psychiatric Genomics Consortium (PGC) for cases and controls in schizophrenia, bipolar disorder, major depressive disorder, autism spectrum disorders (ASD) and attention-deficit/hyperactivity disorder (ADHD). We apply univariate and bivariate methods for the estimation of genetic variation within and covariation between disorders. SNPs explained 17-29% of the variance in …
Psychiatric genome-wide association study analyses implicate neuronal, immune and histone pathways
2015
G.B. and S.N. acknowledge funding support for this work from the National Institute for Health Research (NIHR) Mental Health Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King's College London. P.H.L. is supported by US National Institute of Mental Health (NIMH) grant K99MH101367. Genome-wide association studies (GWAS) of psychiatric disorders have identified multiple genetic associations with such disorders, but better methods are needed to derive the underlying biological mechanisms that these signals indicate. We sought to identify biological pathways in GWAS data from over 60,000 participants from the Psychiatric Genomics Consortium. We developed an an…
Non-linear neuro-inspired circuits and systems: Processing and learning issues
2018
In this chapter the main elements useful for the design and realization of the neural architectures reported in the following chapters will be presented. Considering spiking and non-spiking neurons, the models used for implementing each of them, the synaptic models, the basic learning and plasticity algorithms and the network architectures will be introduced and analysed. The key elements that led to their selection and application in the developed neuro-inspired systems will be discussed briefly.
Are dendrites in Drosophila homologous to vertebrate dendrites?
2005
AbstractDendrites represent arborising neurites in both vertebrates and invertebrates. However, in vertebrates, dendrites develop on neuronal cell bodies, whereas in higher invertebrates, they arise from very different neuronal structures, the primary neurites, which also form the axons. Is this anatomical difference paralleled by principal developmental and/or physiological differences? We address this question by focussing on one cellular model, motorneurons of Drosophila and characterise the compartmentalisation of these cells. We find that motorneuronal dendrites of Drosophila share with typical vertebrate dendrites that they lack presynaptic but harbour postsynaptic proteins, display c…
Microtubule Dynamics and Neuronal Excitability: Advances on Cytoskeletal Components Implicated in Epileptic Phenomena
2020
AbstractExtensive researches have deepened knowledge on the role of synaptic components in epileptogenesis, but limited attention has been devoted to the potential implication of the cytoskeleton. The study of the development of epilepsy and hyperexcitability states involves molecular, synaptic, and structural alterations of neuronal bioelectric activity. In this paper we aim to explore the neurobiological targets involved in microtubule functioning and cytoskeletal transport, i.e. how dynamic scaffolding of microtubules can influence neuronal morphology and excitability, in order to suggest a potential role for microtubule dynamics in the processes turning a normal neuronal network in a hy…
O-glycosylation of the tail domain of neurofilament protein M in human neurons and in spinal cord tissue of a rat model of amyotrophic lateral sclero…
2005
Mammalian neurofilaments (NFs) are modified by post-translational modifications that are thought to regulate NF assembly and organization. Whereas phosphorylation has been intensely studied, the role of another common modification, the attachment of O-linked N-acetylglucosamine (GlcNAc) to individual serine and threonine residues, is hardly understood. We generated a novel monoclonal antibody that specifically recognizes an O-glycosylated epitope in the tail domain of NF-M and allows determination of the glycosylation state at this residue. The antibody displays strong species preference for human NF-M, shows some reactivity with rat but not with mouse or bovine NF-M. By immunohistochemistr…
Transient cortical circuits match spontaneous and sensory-driven activity during development.
2020
At the earliest developmental stages, spontaneous activity synchronizes local and large-scale cortical networks. These networks form the functional template for the establishment of global thalamocortical networks and cortical architecture. The earliest connections are established autonomously. However, activity from the sensory periphery reshapes these circuits as soon as afferents reach the cortex. The early-generated, largely transient neurons of the subplate play a key role in integrating spontaneous and sensory-driven activity. Early pathological conditions—such as hypoxia, inflammation, or exposure to pharmacological compounds—alter spontaneous activity patterns, which subsequently in…
Reawakening the sleeping beauty in the adult brain: neurogenesis from parenchymal glia
2015
Life-long neurogenesis is highly restricted to specialized niches in the adult mammalian brain and therefore the brain's capacity for spontaneous regeneration is extremely limited. However, recent work has demonstrated that under certain circumstances parenchymal astrocytes and NG2 glia can generate neuronal progeny. In the striatum, stroke or excitotoxic lesions can reawaken in astrocytes a latent neurogenic program resulting in the genesis of new neurons. By contrast, in brain areas that fail to mount a neurogenic response following injury, such as the cerebral cortex, forced expression of neurogenic reprogramming factors can lineage convert local glia into induced neurons. Yet, injury-in…