keyword
MENU ▼
Read by QxMD icon Read
search

Synapses

keyword
https://www.readbyqxmd.com/read/28934592/getting-nervous-an-evolutionary-overhaul-for-communication
#1
Frederique Varoqueaux, Dirk Fasshauer
The evolution of a nervous system as a control system of the body's functions is a key innovation of animals. Its fundamental units are neurons, highly specialized cells dedicated to fast cell-cell communication. Neurons pass signals to other neurons, muscle cells, or gland cells at specialized junctions, the synapses, where transmitters are released from vesicles in a Ca(2+)-dependent fashion to activate receptors in the membrane of the target cell. Reconstructing the origins of neuronal communication out of a more simple process remains a central challenge in biology...
September 20, 2017: Annual Review of Genetics
https://www.readbyqxmd.com/read/28934194/arginine-vasopressin-ameliorates-spatial-learning-impairments-in-chronic-cerebral-hypoperfusion-via-v1a-receptor-and-autophagy-signaling-partially
#2
C Yang, X Zhang, J Gao, M Wang, Z Yang
Chronic cerebral hypoperfusion (CCH) is a major factor contributing to neurological disorders and cognitive decline. Autophagy activation is believed to provide both beneficial and detrimental roles during hypoxic/ischemic cellular injury. Although arginine vasopressin (AVP) has been strongly involved in many behaviors, especially in learning and memory, the effects of AVP on CCH and their molecular mechanisms remain unclear. Here, to investigate whether there was neuroprotective effects of AVP on CCH through V1a receptor (an AVP receptor) signaling, permanent bilateral carotid arteries occlusion (two vessel occlusion, 2VO) was used to establish a rat model of CCH, and hypertonic saline (5...
July 18, 2017: Translational Psychiatry
https://www.readbyqxmd.com/read/28932188/is-there-evidence-for-myelin-modeling-by-astrocytes-in-the-normal-adult-brain
#3
Alfredo Varela-Echevarría, Víctor Vargas-Barroso, Carlos Lozano-Flores, Jorge Larriva-Sahd
A set of astrocytic process associated with altered myelinated axons is described in the forebrain of normal adult rodents with confocal, electron microscopy, and 3D reconstructions. Each process consists of a protuberance that contains secretory organelles including numerous lysosomes which polarize and open next to disrupted myelinated axons. Because of the distinctive asymmetric organelle distribution and ubiquity throughout the forebrain neuropil, this enlargement is named paraxial process (PAP). The myelin envelope contiguous to the PAP displays focal disruption or disintegration...
2017: Frontiers in Neuroanatomy
https://www.readbyqxmd.com/read/28932187/linking-network-activity-to-synaptic-plasticity-during-sleep-hypotheses-and-recent-data
#4
REVIEW
Carlos Puentes-Mestril, Sara J Aton
Research findings over the past two decades have supported a link between sleep states and synaptic plasticity. Numerous mechanistic hypotheses have been put forth to explain this relationship. For example, multiple studies have shown structural alterations to synapses (including changes in synaptic volume, spine density, and receptor composition) indicative of synaptic weakening after a period of sleep. Direct measures of neuronal activity and synaptic strength support the idea that a period of sleep can reduce synaptic strength...
2017: Frontiers in Neural Circuits
https://www.readbyqxmd.com/read/28931983/postactivation-depression-of-soleus-h-reflex-increase-with-recovery-of-lower-extremities-motor-functions-in-patients-with-subacute-stroke
#5
Yu Kawaishi, Naoki Matsumoto, Toshiya Nishiwaki, Tatsuro Hirano
[Purpose] The soleus H-reflex is depressed at stimulation rates greater than 0.1 Hz. This reflex depression is referred to as postactivation depression. Postactivation depression reflects the reduced efficacy of the Ia-motoneurons synapses when they are evaluated after a previous activation. The aim of this study was to determine whether the recovery of motor functions in the lower extremities affects the PAD of the soleus H-reflex in patients with subacute stroke undergoing rehabilitation. [Subjects and Methods] Eight patients with subacute stroke patients were recruited...
September 2017: Journal of Physical Therapy Science
https://www.readbyqxmd.com/read/28931944/errant-gardeners-glial-cell-dependent-synaptic-pruning-and-neurodevelopmental-disorders
#6
REVIEW
Urte Neniskyte, Cornelius T Gross
The final stage of brain development is associated with the generation and maturation of neuronal synapses. However, the same period is also associated with a peak in synapse elimination - a process known as synaptic pruning - that has been proposed to be crucial for the maturation of remaining synaptic connections. Recent studies have pointed to a key role for glial cells in synaptic pruning in various parts of the nervous system and have identified a set of critical signalling pathways between glia and neurons...
September 21, 2017: Nature Reviews. Neuroscience
https://www.readbyqxmd.com/read/28931721/neuropeptidergic-integration-of-behavior-in-trichoplax-adhaerens-an-animal-without-synapses
#7
Adriano Senatore, Thomas S Reese, Carolyn L Smith
Trichoplax adhaerens is a flat, millimeter-sized marine animal that adheres to surfaces and grazes on algae. Trichoplax displays a repertoire of different feeding behaviors despite the apparent absence of a true nervous system with electrical or chemical synapses. It glides along surfaces to find food, propelled by beating cilia on cells at its ventral surface, and pauses during feeding by arresting ciliary beating. We found that when endomorphin-like peptides are applied to an animal, ciliary beating is arrested, mimicking natural feeding pauses...
September 15, 2017: Journal of Experimental Biology
https://www.readbyqxmd.com/read/28931651/region-specific-rna-m-6-a-methylation-represents-a-new-layer-of-control-in-the-gene-regulatory-network-in-the-mouse-brain
#8
Mengqi Chang, Hongyi Lv, Weilong Zhang, Chunhui Ma, Xue He, Shunli Zhao, Zhi-Wei Zhang, Yi-Xin Zeng, Shuhui Song, Yamei Niu, Wei-Min Tong
N(6)-methyladenosine (m(6)A) is the most abundant epitranscriptomic mark found on mRNA and has important roles in various physiological processes. Despite the relatively high m(6)A levels in the brain, its potential functions in the brain remain largely unexplored. We performed a transcriptome-wide methylation analysis using the mouse brain to depict its region-specific methylation profile. RNA methylation levels in mouse cerebellum are generally higher than those in the cerebral cortex. Heterogeneity of RNA methylation exists across different brain regions and different types of neural cells including the mRNAs to be methylated, their methylation levels and methylation site selection...
September 2017: Open Biology
https://www.readbyqxmd.com/read/28930540/electrophysiological-evidence-for-long-axis-intrinsic-diversification-of-the-hippocampus
#9
Costas Papatheodoropoulos
The elongated structure of the hippocampus is critically involved in brain functions of profound importance. The segregation of functions along the longitudinal (septotemporal or dorsoventral) axis of the hippocampus is a slowly developed concept and currently is a widely accepted idea. The segregation of neuroanatomical connections along the hippocampal long axis can provide a basis for the interpretation of the functional segregation. However, an emerging and growing body of data strongly suggests the existence of endogenous diversification in the properties of the local neural network along the long axis of the hippocampus...
January 1, 2018: Frontiers in Bioscience (Landmark Edition)
https://www.readbyqxmd.com/read/28930069/initial-elevations-in-glutamate-and-dopamine-neurotransmission-decline-with-age-as-does-exploratory-behavior-in-lrrk2-g2019s-knock-in-mice
#10
Mattia Volta, Dayne A Beccano-Kelly, Sarah A Paschall, Stefano Cataldi, Sarah E MacIsaac, Naila Kuhlmann, Chelsie A Kadgien, Igor Tatarnikov, Jesse Fox, Jaskaran Khinda, Emma Mitchell, Sabrina Bergeron, Heather Melrose, Matthew J Farrer, Austen J Milnerwood
LRRK2 mutations produce end-stage Parkinson's disease (PD) with reduced nigrostriatal dopamine. Conversely, asymptomatic carriers have increased dopamine turnover and altered brain connectivity. LRRK2 pathophysiology remains unclear, but reduced dopamine and mitochondrial abnormalities occur in aged mutant knock-in (GKI) mice. Conversely, cultured GKI neurons exhibit increased synaptic transmission. We assessed behavior and synaptic glutamate and dopamine function across ages. Young GKI exhibit more vertical exploration, elevated glutamate and dopamine transmission, and aberrant D2-receptor responses...
September 20, 2017: ELife
https://www.readbyqxmd.com/read/28928746/ccl5-glutamate-cross-talk-in-astrocyte-neuron-communication-in-multiple-sclerosis
#11
REVIEW
Anna Pittaluga
The immune system (IS) and the central nervous system (CNS) are functionally coupled, and a large number of endogenous molecules (i.e., the chemokines for the IS and the classic neurotransmitters for the CNS) are shared in common between the two systems. These interactions are key elements for the elucidation of the pathogenesis of central inflammatory diseases. In recent years, evidence has been provided supporting the role of chemokines as modulators of central neurotransmission. It is the case of the chemokines CCL2 and CXCL12 that control pre- and/or post-synaptically the chemical transmission...
2017: Frontiers in Immunology
https://www.readbyqxmd.com/read/28928741/cxcl12-mediates-aberrant-costimulation-of-b-lymphocytes-in-warts-hypogammaglobulinemia-infections-myelokathexis-immunodeficiency
#12
Giuliana Roselli, Elisa Martini, Vassilios Lougaris, Raffaele Badolato, Antonella Viola, Marinos Kallikourdis
The Warts, Hypogammaglobulinemia, Infections, Myelokathexis (WHIM) syndrome is an immunodeficiency caused by mutations in chemokine receptor CXCR4. WHIM patient adaptive immunity defects remain largely unexplained. We have previously shown that WHIM-mutant T cells form unstable immunological synapses, affecting T cell activation. Here, we show that, in WHIM patients and WHIM CXCR4 knock-in mice, B cells are more apoptosis prone. Intriguingly, WHIM-mutant B cells were also characterized by spontaneous activation...
2017: Frontiers in Immunology
https://www.readbyqxmd.com/read/28928363/an-autism-spectrum-disorder-related-de-novo-mutation-hotspot-discovered-in-the-gef1-domain-of-trio
#13
Anastasiia Sadybekov, Chen Tian, Cosimo Arnesano, Vsevolod Katritch, Bruce E Herring
The Rho guanine nucleotide exchange factor (RhoGEF) Trio promotes actin polymerization by directly activating the small GTPase Rac1. Recent studies suggest that autism spectrum disorder (ASD)-related behavioral phenotypes in animal models of ASD can be produced by dysregulation of Rac1's control of actin polymerization at glutamatergic synapses. Here, in humans, we discover a large cluster of ASD-related de novo mutations in Trio's Rac1 activating domain, GEF1. Our study reveals that these mutations produce either hypofunctional or hyperfunctional forms of Trio in rodent neurons in vitro...
September 19, 2017: Nature Communications
https://www.readbyqxmd.com/read/28927503/learning-induces-the-translin-trax-rnase-complex-to-express-activin-receptors-for-persistent-memory
#14
Alan Jung Park, Robbert Havekes, Xiuping Fu, Rolf Hansen, Jennifer C Tudor, Lucia Peixoto, Zhi Li, Yen-Ching Wu, Shane G Poplawski, Jay M Baraban, Ted Abel
Long-lasting forms of synaptic plasticity and memory require de novo protein synthesis. Yet, how learning triggers this process to form memory is unclear. Translin/trax is a candidate to drive this learning-induced memory mechanism by suppressing microRNA-mediated translational silencing at activated synapses. We find that mice lacking translin/trax display defects in synaptic tagging, which requires protein synthesis at activated synapses, and long-term memory. Hippocampal samples harvested from these mice following learning show increases in several disease-related microRNAs targeting the activin A receptor type 1C (ACVR1C), a component of the transforming growth factor-β receptor superfamily...
September 20, 2017: ELife
https://www.readbyqxmd.com/read/28927263/molecular-and-cellular-basis-of-neurodegeneration-in-alzheimer-s-disease
#15
Sangyun Jeong
The most common form of senile dementia is Alzheimer's disease (AD), which is characterized by the extracellular deposition of amyloid beta-peptide (Abeta) plaques and the intracellular formation of neurofibrillary tangles (NFTs) in the cerebral cortex. Tau abnormalities are commonly observed in many neurodegenerative diseases including AD, Parkinson's disease, and Pick's disease. Interestingly, tau-mediated formation of NFTs in AD brains shows better correlation with cognitive impairment than Abeta plaque accumulation; pathological tau alone is sufficient to elicit frontotemporal dementia, but it does not cause AD...
September 20, 2017: Molecules and Cells
https://www.readbyqxmd.com/read/28926477/monoamine-and-neuropeptide-connections-significantly-alter-the-degree-distributions-of-the-caenorhabditis-elegans-connectome
#16
Tianxiao Huang, Yan Sun, Zheng Zhang, Shixiong Deng, Rui Peng
To understand the behaviors of an individual, it is crucial to understand the neural connections of the nervous system, that is, the connectome. The hermaphrodite Caenorhabditis elegans connectome has served as a prototype for analytical studies since the chemical synapses and gap junctions among the 302 neurons were completely mapped. Recently, monoamine (MA) and neuropeptide (NP) connections were established, which form a multilayer connectome in conjunction with chemical synapses and gap junctions. In this study, we investigated the difference in the in-degree and out-degree distributions, respectively, among the connectomes with and without MA and NP connections...
September 18, 2017: Neuroreport
https://www.readbyqxmd.com/read/28926472/differential-sensitivity-of-presynaptic-and-postsynaptic-gabab-receptors-in-rat-ventrolateral-periaqueductal-gray
#17
Qian Chen, Caifeng Shao, Hui Zhou, Rui Ma, Ping Jiang, Kun Yang
The ventrolateral periaqueductal gray (PAG) in the midbrain plays a key role in the descending pain modulatory system. γ-Aminobutyric acid type B (GABAB) receptors belong to a metabotropic receptor subfamily and mediate both presynaptic and postsynaptic effects in PAG. It has been well documented that activation of GABAB receptors yields analgesia in some PAG subdivisions. In the present study, employing whole-cell patch-clamp recordings on acute rat PAG slices, we simultaneously monitored the responses of presynaptic and postsynaptic GABAB receptors...
September 18, 2017: Neuroreport
https://www.readbyqxmd.com/read/28926076/electronic-imitation-of-behavioral-and-psychological-synaptic-activities-using-tiox-al2o3-based-memristor-devices
#18
Writam Banerjee, Qi Liu, Hangbing Lv, Shibing Long, Ming Liu
Seeking an effective electronic synapse to emulate biological synaptic behavior is fundamental for building brain-inspired computers. An emerging two-terminal memristor, in which the conductance can be gradually modulated by external electrical stimuli, is widely considered as the strongest competitor of the electronic synapse. Here, we show the capability of TiOx/Al2O3-based memristor devices to imitate synaptic behaviors. Along with analog resistive switching performances, the devices replicate the bio-synapse behaviors of potentiation/depression, short-term-plasticity, and long-term-potentiation, which show that TiOx/Al2O3-based memristors may be useful as electronic synapses...
September 19, 2017: Nanoscale
https://www.readbyqxmd.com/read/28925357/restraint-of-presynaptic-protein-levels-by-wnd-dlk-signaling-mediates-synaptic-defects-associated-with-the-kinesin-3-motor-unc-104
#19
Jiaxing Li, Yao V Zhang, Elham Asghari Adib, Doychin T Stanchev, Xin Xiong, Susan Klinedinst, Pushpanjali Soppina, Thomas Robert Jahn, Richard I Hume, Tobias M Rasse, Catherine A Collins
The kinesin-3 family member Unc-104/KIF1A is required for axonal transport of many presynaptic components to synapses, and mutation of this gene results in synaptic dysfunction in mice, flies and worms. Our studies at the Drosophila neuromuscular junction indicate that many synaptic defects in unc-104-null mutants are mediated independently of Unc-104's transport function, via the Wallenda (Wnd)/DLK MAP kinase axonal damage signaling pathway. Wnd signaling becomes activated when Unc-104's function is disrupted, and leads to impairment of synaptic structure and function by restraining the expression level of active zone (AZ) and synaptic vesicle (SV) components...
September 19, 2017: ELife
https://www.readbyqxmd.com/read/28924012/inhibition-of-il-1%C3%AE-signaling-normalizes-nmda-dependent-neurotransmission-and-reduces-seizure-susceptibility-in-a-mouse-model-of-creutzfeldt-jakob-disease
#20
Ilaria Bertani, Valentina Iori, Massimo Trusel, Mattia Maroso, Claudia Foray, Susanna Mantovani, Raffaella Tonini, Annamaria Vezzani, Roberto Chiesa
Creutzfeldt-Jakob disease (CJD) is a neurodegenerative disorder caused by prion protein (PrP) misfolding, clinically recognized by cognitive and motor deficits, electroencephalographic (EEG) abnormalities and seizures. Its neurophysiological bases are not known. To assess the potential involvement of N-methyl-D-aspartate receptor (NMDAR) dysfunction, we analyzed NMDA-dependent synaptic plasticity in hippocampal slices from Tg(CJD) mice, which model a genetic form of CJD. Because PrP depletion may result in functional upregulation of NMDARs, we also analyzed PrP knockout (KO) mice...
September 18, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
keyword
keyword
16972
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"