keyword
MENU ▼
Read by QxMD icon Read
search

corticospinal

keyword
https://www.readbyqxmd.com/read/28072502/wallerian-degeneration-beyond-the-corticospinal-tracts-conventional-and-advanced-mri-findings
#1
REVIEW
Yin Jie Chen, Seyed Ali Nabavizadeh, Arastoo Vossough, Sunil Kumar, Laurie A Loevner, Suyash Mohan
Wallerian degeneration (WD) is defined as progressive anterograde disintegration of axons and accompanying demyelination after an injury to the proximal axon or cell body. Since the 1980s and 1990s, conventional magnetic resonance imaging (MRI) sequences have been shown to be sensitive to changes of WD in the subacute to chronic phases. More recently, advanced MRI techniques, such as diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI), have demonstrated some of earliest changes attributed to acute WD, typically on the order of days...
November 7, 2016: Journal of Neuroimaging: Official Journal of the American Society of Neuroimaging
https://www.readbyqxmd.com/read/28070912/role-of-testosterone-and-y-chromosome-genes-for-the-masculinization-of-the-human-brain
#2
Ivanka Savic, Louise Frisen, Amirhossein Manzouri, Anna Nordenstrom, Angelica Lindén Hirschberg
: Women with complete androgen insensitivity syndrome (CAIS) have a male (46,XY) karyotype but no functional androgen receptors. Their condition, therefore, offers a unique model for studying testosterone effects on cerebral sex dimorphism. We present MRI data from 16 women with CAIS and 32 male (46,XY) and 32 female (46,XX) controls. METHODS: FreeSurfer software was employed to measure cortical thickness and subcortical structural volumes. Axonal connections, indexed by fractional anisotropy, (FA) were measured with diffusion tensor imaging, and functional connectivity with resting state fMRI...
January 10, 2017: Human Brain Mapping
https://www.readbyqxmd.com/read/28069760/axotomized-corticospinal-neurons-increase-supra-lesional-innervation-and-remain-crucial-for-skilled-reaching-after-bilateral-pyramidotomy
#3
Alice C Mosberger, Jenifer C Miehlbradt, Nadja Bjelopoljak, Marc P Schneider, Anna-Sophia Wahl, Benjamin V Ineichen, Miriam Gullo, Martin E Schwab
Skilled upper limb function heavily depends on the corticospinal tract. After bilateral lesions to this tract, motor control is disrupted but can be partially substituted by other motor systems to allow functional recovery. However, the remaining roles of motor cortex and especially of axotomized corticospinal neurons (CSNs) are not well understood. Using the single pellet retrieval task in adult rats, we induced significant recovery of skilled reaching after bilateral pyramidotomy by rehabilitative reaching training, and show that reach-related motor cortex activity, recorded in layer V, topographically reappeared shortly after axotomy...
January 8, 2017: Cerebral Cortex
https://www.readbyqxmd.com/read/28068522/motor-evoked-potential-gain-is-a-helpful-test-for-the-detection-of-corticospinal-tract-dysfunction-in-amyotrophic-lateral-sclerosis
#4
Y Duclos, A M Grapperon, E Jouve, R Truillet, C Zemmour, A Verschueren, J Pouget, S Attarian
OBJECTIVE: The detection of upper motor neuron (UMN) dysfunction is necessary for the diagnosis of amyotrophic lateral sclerosis (ALS). However, signs of UMN dysfunction may be difficult to establish. This study aimed to determine whether motor-evoked potential (MEP) gain (MEP area/background electromyographic activity) represents an efficient alternative to assess UMN dysfunction. METHODS: MEP area, MEP/compound muscle action potential (CMAP) area ratio, and MEP gain were tested at different force levels in healthy control subjects and ALS patients...
December 23, 2016: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
https://www.readbyqxmd.com/read/28060035/etiology-and-recovery-of-neuromuscular-fatigue-following-simulated-soccer-match-play
#5
Kevin Thomas, Jack Dent, Glyn Howatson, Stuart Goodall
PURPOSE: We profiled the etiology and recovery of neuromuscular fatigue post-simulated-soccer-match-play. METHODS: Fifteen semi-professional players completed a 90 min simulated soccer match. Pre-, immediately-post and at 24, 48 and 72 h participants completed a battery of neuromuscular, physical and perceptual tests. Perceived fatigue and muscle soreness were assessed via visual analogue scales. Maximum voluntary contraction (MVC) and twitch responses to electrical (femoral nerve) and magnetic (motor cortex) stimulation during isometric knee-extensor contractions and at rest were measured to assess central (voluntary activation, VA) and peripheral (quadriceps potentiated twitch force, Qtw,pot) fatigue, and responses to single and paired-magnetic stimuli were assessed to quantify corticospinal excitability and short-intracortical inhibition (SICI), respectively...
January 3, 2017: Medicine and Science in Sports and Exercise
https://www.readbyqxmd.com/read/28057929/a-novel-role-for-the-dna-repair-gene-rad51-in-netrin-1-signalling
#6
K A Glendining, D Markie, R J M Gardner, E A Franz, S P Robertson, C L Jasoni
Mutations in RAD51 have recently been linked to human Congenital Mirror Movements (CMM), a developmental disorder of the motor system. The only gene previously linked to CMM encodes the Netrin-1 receptor DCC, which is important for formation of corticospinal and callosal axon tracts. Thus, we hypothesised that Rad51 has a novel role in Netrin-1-mediated axon development. In mouse primary motor cortex neurons, Rad51 protein was redistributed distally down the axon in response to Netrin-1, further suggesting a functional link between the two...
January 6, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28053857/are-we-armed-with-the-right-data-pooled-individual-data-review-of-biomarkers-in-people-with-severe-upper-limb-impairment-after-stroke
#7
Kathryn S Hayward, Julia Schmidt, Keith R Lohse, Sue Peters, Julie Bernhardt, Natasha A Lannin, Lara A Boyd
: To build an understanding of the neurobiology underpinning arm recovery in people with severe arm impairment due to stroke, we conducted a pooled individual data systematic review to: 1) characterize brain biomarkers; 2) determine relationship(s) between biomarkers and motor outcome; and 3) establish relationship(s) between biomarkers and motor recovery. Three electronic databases were searched up to October 2, 2015. Eligible studies included adults with severe arm impairment after stroke...
2017: NeuroImage: Clinical
https://www.readbyqxmd.com/read/28050345/functional-mri-vs-navigated-tms-to-optimize-m1-seed-volume-delineation-for-dti-tractography-a-prospective-study-in-patients-with-brain-tumours-adjacent-to-the-corticospinal-tract
#8
Carolin Weiss Lucas, Irada Tursunova, Volker Neuschmelting, Charlotte Nettekoven, Ana-Maria Oros-Peusquens, Gabriele Stoffels, Andrea Maria Faymonville, Shah N Jon, Karl Josef Langen, Hannah Lockau, Roland Goldbrunner, Christian Grefkes
BACKGROUND: DTI-based tractography is an increasingly important tool for planning brain surgery in patients suffering from brain tumours. However, there is an ongoing debate which tracking approaches yield the most valid results. Especially the use of functional localizer data such as navigated transcranial magnetic stimulation (nTMS) or functional magnetic resonance imaging (fMRI) seem to improve fibre tracking data in conditions where anatomical landmarks are less informative due to tumour-induced distortions of the gyral anatomy...
2017: NeuroImage: Clinical
https://www.readbyqxmd.com/read/28049844/contribution-of-propriospinal-neurons-to-recovery-of-hand-dexterity-after-corticospinal-tract-lesions-in-monkeys
#9
Takamichi Tohyama, Masaharu Kinoshita, Kenta Kobayashi, Kaoru Isa, Dai Watanabe, Kazuto Kobayashi, Meigen Liu, Tadashi Isa
The direct cortico-motoneuronal connection is believed to be essential for the control of dexterous hand movements, such as precision grip in primates. It was reported, however, that even after lesion of the corticospinal tract (CST) at the C4-C5 segment, precision grip largely recovered within 1-3 mo, suggesting that the recovery depends on transmission through intercalated neurons rostral to the lesion, such as the propriospinal neurons (PNs) in the midcervical segments. To obtain direct evidence for the contribution of PNs to recovery after CST lesion, we applied a pathway-selective and reversible blocking method using double viral vectors to the PNs in six monkeys after CST lesions at C4-C5...
January 3, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28046689/su-f-t-118-characterization-of-change-in-fractional-anisotropy-after-radiation-therapy-does-nearby-disruption-predict-for-white-matter-damage
#10
N Pettersson, R Karunamuni, M Connor, V Moiseenko, A Dale, H Bartsch, J Brewer, A Krishnan, J Kuperman, D Hagler, C McDonald, N Farid, N White, J Hattangadi-Gluth, L Cervino
PURPOSE: We investigated predictors of fractional anisotropy (FA) change in the corticospinal white matter tract (CST) following radiation therapy (RT). METHODS: Diffusion tensor imaging (DTI) is a non-invasive modality which models water diffusion properties. FA quantifies the extent of directional bias-a decrease indicates disrupted white matter integrity. Fifteen patients with high-grade glioma underwent DTI scans before, and ten months after RT to 59.4-60 Gy...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28045853/intraoperative-neuromonitoring-and-alarm-criteria-for-judging-mep-responses-to-transcranial-electric-stimulation-the-threshold-level-method
#11
Blair Calancie
The motor evoked potential (MEP) is used in the operating room to gauge-and ultimately protect-the functional integrity of the corticospinal tract (CST). However, there is no consensus as to how to best interpret the MEP for maximizing its sensitivity and specificity to CST compromise. The most common way is to use criteria associated with response magnitude (response amplitude; waveform complexity, etc.). With this approach, should an MEP in response to a fixed stimulus intensity diminish below some predetermined cutoff, suggesting CST dysfunction, then the surgical team is warned...
January 2017: Journal of Clinical Neurophysiology: Official Publication of the American Electroencephalographic Society
https://www.readbyqxmd.com/read/28041852/the-cellular-and-synaptic-architecture-of-the-mechanosensory-dorsal-horn
#12
Victoria E Abraira, Emily D Kuehn, Anda M Chirila, Mark W Springel, Alexis A Toliver, Amanda L Zimmerman, Lauren L Orefice, Kieran A Boyle, Ling Bai, Bryan J Song, Karleena A Bashista, Thomas G O'Neill, Justin Zhuo, Connie Tsan, Jessica Hoynoski, Michael Rutlin, Laura Kus, Vera Niederkofler, Masahiko Watanabe, Susan M Dymecki, Sacha B Nelson, Nathaniel Heintz, David I Hughes, David D Ginty
The deep dorsal horn is a poorly characterized spinal cord region implicated in processing low-threshold mechanoreceptor (LTMR) information. We report an array of mouse genetic tools for defining neuronal components and functions of the dorsal horn LTMR-recipient zone (LTMR-RZ), a role for LTMR-RZ processing in tactile perception, and the basic logic of LTMR-RZ organization. We found an unexpectedly high degree of neuronal diversity in the LTMR-RZ: seven excitatory and four inhibitory subtypes of interneurons exhibiting unique morphological, physiological, and synaptic properties...
January 12, 2017: Cell
https://www.readbyqxmd.com/read/28040732/mutant-profilin1-transgenic-mice-recapitulate-cardinal-features-of-motor-neuron-disease
#13
Daniel Fil, Abigail DeLoach, Shilpi Yadav, Duah Alkam, Melanie MacNicol, Awantika Singh, Cesar M Compadre, Joseph J Goellner, Charles A O'Brien, Tariq Fahmi, Alexei G Basnakian, Noel Y Calingasan, Jodi L Klessner, M Flint Beal, Owen M Peters, Jake Metterville, Robert H Brown, Karen K Y Ling, Frank Rigo, P Hande Ozdinler, Mahmoud Kiaei
The recent identification of profilin1 mutations in 25 familial ALS cases has linked altered function of this cytoskeleton-regulating protein to the pathogenesis of motor neuron disease. To investigate the pathological role of mutant profilin1 in motor neuron disease, we generated transgenic lines of mice expressing human profilin1 with a mutation at position 118 (hPFN1(G118V)). One of the mouse lines expressing high levels of mutant human PFN1 protein in the brain and spinal cord exhibited many key clinical and pathological features consistent with human ALS disease...
December 30, 2016: Human Molecular Genetics
https://www.readbyqxmd.com/read/28033506/preconditioning-tdcs-facilitates-subsequent-tdcs-effect-on-skill-acquisition-in-older-adults
#14
Hakuei Fujiyama, Mark R Hinder, Azadeh Barzideh, Charis Van de Vijver, Andreea C Badache, Maria Nathalya Manrique-C, Paola Reissig, Xue Zhang, Oron Levin, Jeffery J Summers, Stephan P Swinnen
Functional motor declines that often occur with advancing age-including reduced efficacy to learn new skills-can have a substantial impact on the quality of life. Recent studies using noninvasive brain stimulation indicate that priming the corticospinal system by lowering the threshold for the induction of long-term potentiation-like plasticity before skill training may facilitate subsequent skill learning. Here, we used "priming" protocol, in which we used transcranial direct current stimulation (tDCS) applying the cathode over the primary motor cortex (M1) before the anode placed over M1 during unimanual isometric force control training (FORCEtraining)...
December 1, 2016: Neurobiology of Aging
https://www.readbyqxmd.com/read/28033250/radiologic-features-of-primary-intracranial-ectopic-germinomas-case-reports-and-literature-review
#15
Xin-Hua Wei, Hui-Cong Shen, Shou-Xian Tang, Cui-Hua Gao, Ji-Liang Ren, Lin Ai, Jian-Ping Dai
RATIONALE: Germinomas are sensitive to radiation therapy and chemotherapy; therefore, correct imaging diagnosis is crucial for them. However, the imaging findings of germinomas originating from off-midline regions displayed different patterns from those originating from midline areas. PATIENT CONCERNS: The objective of this study is to describe the radiologic features of primary ectopic germinoma. We reviewed the MR and CT findings of 12 patients with histologically proven off-midline ectopic germinomas with off-midline locations...
December 2016: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28031404/physiological-processes-influencing-motor-evoked-potential-duration-with-voluntary-contraction
#16
Mehdi Aj van den Bos, Nimeshan Geevasinga, Parvathi Menon, David Burke, Matthew C Kiernan, Steve Vucic
Voluntary contraction leads to facilitation of motor evoked potentials (MEPs) producing greater amplitude, shorter onset latency and prolonged duration of the EMG potential. While hyperexcitability of spinal motoneurons and changes in descending corticospinal volleys have been proposed as putative mechanisms for changes in MEP amplitude and onset latency, a contribution of propriospinal interneurons, exerting modulatory effects on α motoneurons, has been proposed as a potential explanation for prolongation of MEP duration...
December 28, 2016: Journal of Neurophysiology
https://www.readbyqxmd.com/read/28019046/evaluation-of-neonatal-brain-myelination-using-the-t1-and-t2-weighted-mri-ratio
#17
Jennifer E Soun, Michael Z Liu, Keith A Cauley, Jack Grinband
PURPOSE: To validate the T1- and T2-weighted (T1w/T2w) MRI ratio technique in evaluating myelin in the neonatal brain. MATERIALS AND METHODS: T1w and T2w MR images of 10 term neonates with normal-appearing brain parenchyma were obtained from a single 1.5 Tesla MRI and retrospectively analyzed. T1w/T2w ratio images were created with a postprocessing pipeline and qualitatively compared with standard clinical sequences (T1w, T2w, and apparent diffusion coefficient [ADC])...
December 26, 2016: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28017534/direct-motor-evoked-potentials-and-cortical-mapping-using-the-nim%C3%A2-nerve-monitoring-system-a-technical-note
#18
Suparna Bharadwaj, Faizal Haji, Matthew Hebb, Jason Chui
Motor evoked potentials (MEPs) are commonly used to prevent neurological injury when operating in close proximity to the motor cortex or corticospinal pathway. We report a novel application of the NIM® nerve monitoring system (Medtronic@ NIM response 3.0) for intraoperative direct cortical (dc)-MEPs monitoring. A 69-year-old female patient presented with a 4month history of progressive left hemiparesis resulting from a large right sided posterior frontal meningioma that abutted and compressed the motor cortex...
December 22, 2016: Journal of Clinical Neuroscience: Official Journal of the Neurosurgical Society of Australasia
https://www.readbyqxmd.com/read/28012640/white-matter-integrity-and-symptom-dimensions-of-schizophrenia-a-diffusion-tensor-imaging-study
#19
Miriam H A Bopp, Rebecca Zöllner, Andreas Jansen, Bruno Dietsche, Axel Krug, Tilo T J Kircher
Impaired fiber bundle connectivity between brain regions is a key neuropathological finding in schizophrenia. Symptom dimensions in schizophrenia can be clustered into factor models. Single syndromes have been related to grey and white matter brain structure alterations. We associated all core syndromes of schizophrenia in a single patient group with changes in white matter integrity. Diffusion weighted images (3T MRI) and SAPS/SANS scores were measured in 26 male patients and 26 healthy controls. First, group differences in fractional anisotropy (FA) were calculated with TBSS...
December 21, 2016: Schizophrenia Research
https://www.readbyqxmd.com/read/28005989/action-video-game-playing-is-reflected-in-enhanced-visuomotor-performance-and-increased-corticospinal-excitability
#20
Olivier Morin-Moncet, Jean-Marc Therrien-Blanchet, Marie C Ferland, Hugo Théoret, Greg L West
Action video game playing is associated with improved visuomotor performance; however, the underlying neural mechanisms associated with this increased performance are not well understood. Using the Serial Reaction Time Task in conjunction with Transcranial Magnetic Stimulation, we investigated if improved visuomotor performance displayed in action video game players (actionVGPs) was associated with increased corticospinal plasticity in primary motor cortex (M1) compared to non-video game players (nonVGPs). Further, we assessed if actionVGPs and nonVGPs displayed differences in procedural motor learning as measured by the SRTT...
2016: PloS One
keyword
keyword
50226
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"