keyword
MENU ▼
Read by QxMD icon Read
search

Synaptic scaling

keyword
https://www.readbyqxmd.com/read/28714852/the-small-molecule-mimetic-agonist-trimebutine-of-adhesion-molecule-l1-contributes-to-functional-recovery-after-spinal-cord-injury-in-mice
#1
Junping Xu, Chengliang Hu, Qiong Jiang, Hongchao Pan, Huifan Shen, Melitta Schachner
Curing spinal cord injury (SCI) in mammals is a daunting task because of the lack of permissive mechanisms and strong inhibitory responses at and around the lesion. The neural cell adhesion molecule L1CAM (L1) has been shown to favor axonal regrowth and enhance neuronal survival and synaptic plasticity, and thus constitutes a viable target to promote regeneration after SCI. Since delivery of full-length L1 or its extracellular domain could encounter difficulties in translation to therapy in humans, we have identified several small organic compounds that bind to L1 and stimulate neuronal survival, neuronal migration, and neurite outgrowth in an L1-dependent manner...
July 14, 2017: Disease Models & Mechanisms
https://www.readbyqxmd.com/read/28708060/synem-automated-synapse-detection-for-connectomics
#2
Benedikt Staffler, Manuel Berning, Kevin M Boergens, Anjali Gour, Patrick van der Smagt, Moritz Helmstaedter
Nerve tissue contains a high density of chemical synapses, about 1 per µm(3) in the mammalian cerebral cortex. Thus, even for small blocks of nerve tissue, dense connectomic mapping requires the identification of millions to billions of synapses. While the focus of connectomic data analysis has been on neurite reconstruction, synapse detection becomes limiting when datasets grow in size and dense mapping is required. Here, we report SynEM, a method for automated detection of synapses from conventionally en-bloc stained 3D electron microscopy image stacks...
July 14, 2017: ELife
https://www.readbyqxmd.com/read/28706303/memristive-neural-network-for-on-line-learning-and-tracking-with-brain-inspired-spike-timing-dependent-plasticity
#3
G Pedretti, V Milo, S Ambrogio, R Carboni, S Bianchi, A Calderoni, N Ramaswamy, A S Spinelli, D Ielmini
Brain-inspired computation can revolutionize information technology by introducing machines capable of recognizing patterns (images, speech, video) and interacting with the external world in a cognitive, humanlike way. Achieving this goal requires first to gain a detailed understanding of the brain operation, and second to identify a scalable microelectronic technology capable of reproducing some of the inherent functions of the human brain, such as the high synaptic connectivity (~10(4)) and the peculiar time-dependent synaptic plasticity...
July 13, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28704399/cooperative-stochastic-binding-and-unbinding-explain-synaptic-size-dynamics-and-statistics
#4
Aseel Shomar, Lukas Geyrhofer, Noam E Ziv, Naama Brenner
Synapses are dynamic molecular assemblies whose sizes fluctuate significantly over time-scales of hours and days. In the current study, we examined the possibility that the spontaneous microscopic dynamics exhibited by synaptic molecules can explain the macroscopic size fluctuations of individual synapses and the statistical properties of synaptic populations. We present a mesoscopic model, which ties the two levels. Its basic premise is that synaptic size fluctuations reflect cooperative assimilation and removal of molecules at a patch of postsynaptic membrane...
July 13, 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28694016/-18-f-fdopa-positron-emission-tomography-in-manganese-exposed-workers
#5
Susan R Criswell, Susan Searles Nielsen, Mark Warden, Joel S Perlmutter, Stephen M Moerlein, Hubert P Flores, John Huang, Lianne Sheppard, Noah Seixas, Harvey Checkoway, Brad A Racette
Occupational manganese (Mn) exposure is associated with the development of parkinsonism; however, the mechanism of neurotoxicity is unknown. Brain positron emission tomography (PET) imaging provides a non-invasive method of assessing dopamineric neuronal function. 6-[(18)F]fluoro-L-DOPA (FDOPA) PET reflects in-vivo nigrostriatal function, but results in Mn exposure are conflicting. The objective of this study was to investigate the association between Mn exposure secondary to occupational welding, FDOPA striatal uptake, and clinical parkinsonism as measured by Unified Parkinson Disease Rating Scale motor subscore 3 (UPDRS3) scores...
July 7, 2017: Neurotoxicology
https://www.readbyqxmd.com/read/28692643/inverse-stochastic-resonance-in-networks-of-spiking-neurons
#6
Muhammet Uzuntarla, Ernest Barreto, Joaquin J Torres
Inverse Stochastic Resonance (ISR) is a phenomenon in which the average spiking rate of a neuron exhibits a minimum with respect to noise. ISR has been studied in individual neurons, but here, we investigate ISR in scale-free networks, where the average spiking rate is calculated over the neuronal population. We use Hodgkin-Huxley model neurons with channel noise (i.e., stochastic gating variable dynamics), and the network connectivity is implemented via electrical or chemical connections (i.e., gap junctions or excitatory/inhibitory synapses)...
July 10, 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28691903/sequential-neuromodulation-of-hebbian-plasticity-offers-mechanism-for-effective-reward-based-navigation
#7
Zuzanna Brzosko, Sara Zannone, Wolfram Schultz, Claudia Clopath, Ole Paulsen
Spike timing-dependent plasticity (STDP) is under neuromodulatory control, which is correlated with distinct behavioral states. Previously we reported that dopamine, a reward signal, broadens the time window for synaptic potentiation and modulates the outcome of hippocampal STDP even when applied after the plasticity induction protocol (Brzosko et al., 2015). Here we demonstrate that sequential neuromodulation of STDP by acetylcholine and dopamine offers an efficacious model of reward-based navigation. Specifically, our experimental data in mouse hippocampal slices show that acetylcholine biases STDP towards synaptic depression, whilst subsequent application of dopamine converts this depression into potentiation...
July 10, 2017: ELife
https://www.readbyqxmd.com/read/28689352/synapse-fits-neuron-joint-reduction-by-model-inversion
#8
H T van der Scheer, A Doelman
In this paper, we introduce a novel simplification method for dealing with physical systems that can be thought to consist of two subsystems connected in series, such as a neuron and a synapse. The aim of our method is to help find a simple, yet convincing model of the full cascade-connected system, assuming that a satisfactory model of one of the subsystems, e.g., the neuron, is already given. Our method allows us to validate a candidate model of the full cascade against data at a finer scale. In our main example, we apply our method to part of the squid's giant fiber system...
July 8, 2017: Biological Cybernetics
https://www.readbyqxmd.com/read/28684604/a-neurotransmitter-atlas-of-the-caenorhabditis-elegans-male-nervous-system-reveals-sexually-dimorphic-neurotransmitter-usage
#9
Esther Serrano-Saiz, Laura Pereira, Marie Gendrel, Ulkar Aghayeva, Abhishek Battacharya, Kelly Howell, L Rene Garcia, Oliver Hobert
The nervous system of most animals is sexually dimorphic but such dimorphisms are generally poorly mapped on an anatomical, cellular, and molecular level. The adult nervous system of the nematode Caenorhabditis elegans displays a number of clearly defined anatomical sexual dimorphisms, but molecular features of sexually dimorphic neurons remain sparse. In this resource paper, we provide a comprehensive atlas of neurotransmitters used in the nervous system of the male and compare it to that of the hermaphrodite...
July 2017: Genetics
https://www.readbyqxmd.com/read/28679595/poor-sleep-is-associated-with-csf-biomarkers-of-amyloid-pathology-in-cognitively-normal-adults
#10
Kate E Sprecher, Rebecca L Koscik, Cynthia M Carlsson, Henrik Zetterberg, Kaj Blennow, Ozioma C Okonkwo, Mark A Sager, Sanjay Asthana, Sterling C Johnson, Ruth M Benca, Barbara B Bendlin
OBJECTIVE: To determine the relationship between sleep quality and CSF markers of Alzheimer disease (AD) pathology in late midlife. METHODS: We investigated the relationship between sleep quality and CSF AD biomarkers in a cohort enriched for parental history of sporadic AD, the Wisconsin Registry for Alzheimer's Prevention. A total of 101 participants (mean age 62.9 ± 6.2 years, 65.3% female) completed sleep assessments and CSF collection and were cognitively normal...
July 5, 2017: Neurology
https://www.readbyqxmd.com/read/28676297/inferring-synaptic-excitation-inhibition-balance-from-field-potentials
#11
Richard Gao, Erik J Peterson, Bradley Voytek
Neural circuits sit in a dynamic balance between excitation (E) and inhibition (I). Fluctuations in E:I balance have been shown to influence neural computation, working memory, and information flow, while more drastic shifts and aberrant E:I patterns are implicated in numerous neurological and psychiatric disorders. Current methods for measuring E:I dynamics require invasive procedures that are difficult to perform in behaving animals, and nearly impossible in humans. This has limited the ability to examine the full impact that E:I shifts have in cognition and disease...
July 1, 2017: NeuroImage
https://www.readbyqxmd.com/read/28672189/multi-scale-modeling-of-altered-synaptic-plasticity-related-to-amyloid-%C3%AE-effects
#12
Takumi Matsuzawa, László Zalányi, Tamás Kiss, Péter Érdi
As suggested by Palop and Mucke (2010) pathologically elevated β-amyloid (Aβ) impairs long term potentiation (LTP) and enhances long term depression (LTD) possible underlying mechanisms in Alzheimer's Disease (AD). In the present paper we adopt and further elaborate a phenomenological computational model of bidirectional plasticity based on the calcium control hypothesis of Shouval et al. (2002). First, to account for Aβ effects the activation function Ω was modified assuming competition between LTP and LTD, and parameter sets were identified that well describe both normal and pathological synaptic plasticity processes...
June 20, 2017: Neural Networks: the Official Journal of the International Neural Network Society
https://www.readbyqxmd.com/read/28671332/association-between-malnutrition-and-hyperhomocysteine-in-alzheimer-s-disease-patients-and-diet-intervention-of-betaine
#13
Jianying Sun, Shiling Wen, Jing Zhou, Shuling Ding
BACKGROUND: Alzheimer's disease (AD) is a neurodegenerative disease, which is associated with malnutrition and hyperhomocysteine. The current study aimed to analyze the relationship between malnutrition and hyperhomocysteine in AD patients, and effects of diet intervention with betaine on the disease. METHODS: The nutritional statuses of the AD patients were assessed by short form mini nutritional assessment (MNA-SF). The levels of Hcy, tau hyperphosphorylation, synaptic proteins, blood inflammatory factors were measured by enzymatic cycling assay, Western blot and ELISA...
November 7, 2016: Journal of Clinical Laboratory Analysis
https://www.readbyqxmd.com/read/28652968/acute-effects-and-after-effects-of-acoustic-coordinated-reset-neuromodulation-in-patients-with-chronic-subjective-tinnitus
#14
Ilya Adamchic, Timea Toth, Christian Hauptmann, Martin Walger, Berthold Langguth, Ingrid Klingmann, Peter Alexander Tass
Chronic subjective tinnitus is an auditory phantom phenomenon characterized by abnormal neuronal synchrony in the central auditory system. As shown computationally, acoustic coordinated reset (CR) neuromodulation causes a long-lasting desynchronization of pathological synchrony by downregulating abnormal synaptic connectivity. In a previous proof of concept study acoustic CR neuromodulation, employing stimulation tone patterns tailored to the dominant tinnitus frequency, was compared to noisy CR-like stimulation, a CR version significantly detuned by sparing the tinnitus-related pitch range and including substantial random variability of the tone spacing on the frequency axis...
2017: NeuroImage: Clinical
https://www.readbyqxmd.com/read/28649607/synaptic-proteins-in-csf-relate-to-parkinson-s-disease-stage-markers
#15
Erika Bereczki, Anna Bogstedt, Kina Höglund, Panagiota Tsitsi, Lovisa Brodin, Clive Ballard, Per Svenningsson, Dag Aarsland
Recent findings of morphological and functional changes in Parkinson's disease brains have shown altered synapse formation, but their role in cognitive decline is still an area under exploration. Here we measured the concentration of three key synaptic proteins, Rab3A, SNAP25 and neurogranin by enzyme-linked immunosorbent assay, in cerebrospinal fluid from a total of 139 participants (87 controls and 52 Parkinson's disease patients out of which 30 were drug-naïve) and explored their associations with motor and cognitive symptoms...
2017: NPJ Parkinson's Disease
https://www.readbyqxmd.com/read/28636578/human-neuropsin-gene-in-depression
#16
Kinga Bobińska, Joanna Mossakowska-Wójcik, Janusz Szemraj, Piotr Gałecki, Marlena Zajączkowska, Monika Talarowska
BACKGROUND: Neuropsin (NP, kallikrein 8, KLK8) - a kallikrein gene-related (KLK) endoprotease - plays a key role in neuroplasticity processes, since intracellular signal cascades and regulation of gene expression are engaged in long-term synaptic plasticity. The main aim of this paper is to compare expression of the human neuropsin gene on the mRNA level in a group of patients diagnosed with depression and in a group of healthy subjects who have never been treated psychiatrically. SUBJECTS AND METHODS: 291 people, aged 18-67, were qualified to participate in the experiment: major recurrent depression group (MRD) and the control group (CG)...
June 2017: Psychiatria Danubina
https://www.readbyqxmd.com/read/28632905/the-malleable-brain-plasticity-of-neural-circuits-and-behavior-a-review-from-students-to-students
#17
REVIEW
Natascha Schaefer, Carola Rotermund, Eva-Maria Blumrich, Mychael V Lourenco, Pooja Joshi, Regina U Hegemann, Sumit Jamwal, Nilufar Ali, Ezra Michelet García Romero, Sorabh Sharma, Shampa Ghosh, Jitendra K Sinha, Hannah Loke, Vishal Jain, Katarzyna Lepeta, Ahmad Salamian, Mahima Sharma, Mojtaba Golpich, Katarzyna Nawrotek, Ramesh K Paidi, Sheila M Shahidzadeh, Tetsade Piermartiri, Elham Amini, Veronica Pastor, Yvette Wilson, Philip A Adeniyi, Ashok K Datusalia, Benham Vafadari, Vedangana Saini, Edna Suárez-Pozos, Neetu Kushwah, Paula Fontanet, Anthony J Turner
One of the most intriguing features of the brain is its ability to be malleable, allowing it to adapt continually to changes in the environment. Specific neuronal activity patterns drive long-lasting increases or decreases in the strength of synaptic connections, referred to as long-term potentiation (LTP) and long-term depression (LTD) respectively. Such phenomena have been described in a variety of model organisms, which are used to study molecular, structural, and functional aspects of synaptic plasticity...
June 20, 2017: Journal of Neurochemistry
https://www.readbyqxmd.com/read/28624138/serum-ncam-levels-and-cognitive-deficits-in-first-episode-schizophrenia-patients-versus-health-controls
#18
HuiMei An, LuPing Zhou, Yinghua Yu, Hongzhen Fan, FengMei Fan, Shuping Tan, ZhiRen Wang, Boz Z, Jing Shi, FuDe Yang, Xiangyang Zhang, Yunlong Tan, Xu-Feng Huang
BACKGROUND: Neural cell adhesion molecule (NCAM) is a glycoprotein and plays an important role in cell-cell adhesion, neural migration, neurite outgrowth, synaptic plasticity and brain development. We investigated the relationship between the serum NCAM concentration and cognitive deficit in first episode drug naïve schizophrenia (FES) patients. METHODS: Thirty FES patients and thirty healthy controls were recruited for this study. Psychiatric symptoms were assessed by the positive and negative syndrome scale (PANSS)...
June 15, 2017: Schizophrenia Research
https://www.readbyqxmd.com/read/28621434/eea1-restores-homeostatic-synaptic-plasticity-in-hippocampal-neurons-from-rett-syndrome-mice
#19
Xin Xu, Lucas Pozzo-Miller
Rett syndrome is a neurodevelopmental disorder caused by loss-of-function mutations in MECP2, the gene encoding the transcriptional regulator methyl-CpG-binding protein 2 (MeCP2). Deletion of Mecp2 in mice results in an imbalance of synaptic excitation and inhibition in hippocampal pyramidal neurons, which affects "Hebbian" long-term synaptic plasticity. Since the excitatory/inhibitory (E/I) balance is maintained by homeostatic mechanisms, we examined the role of MeCP2 in homeostatic synaptic plasticity (HSP) at excitatory synapses...
June 16, 2017: Journal of Physiology
https://www.readbyqxmd.com/read/28619476/brexanolone-sage-547-injection-in-post-partum-depression-a-randomised-controlled-trial
#20
Stephen Kanes, Helen Colquhoun, Handan Gunduz-Bruce, Shane Raines, Ryan Arnold, Amy Schacterle, James Doherty, C Neill Epperson, Kristina M Deligiannidis, Robert Riesenberg, Ethan Hoffmann, David Rubinow, Jeffrey Jonas, Steven Paul, Samantha Meltzer-Brody
BACKGROUND: Post-partum depression is a serious mood disorder in women that might be triggered by peripartum fluctuations in reproductive hormones. This phase 2 study investigated brexanolone (USAN; formerly SAGE-547 injection), an intravenous formulation of allopregnanolone, a positive allosteric modulator of γ-aminobutyric acid (GABAA) receptors, for the treatment of post-partum depression. METHODS: For this double-blind, randomised, placebo-controlled trial, we enrolled self-referred or physician-referred female inpatients (≤6 months post partum) with severe post-partum depression (Hamilton Rating Scale for Depression [HAM-D] total score ≥26) in four hospitals in the USA...
June 12, 2017: Lancet
keyword
keyword
11718
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"