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https://www.readbyqxmd.com/read/29154969/adults-with-cystic-fibrosis-have-deficits-in-bone-structure-and-strength-at-the-distal-tibia-despite-similar-size-and-measuring-standard-and-relative-sites
#1
Kyle K Nishiyama, Sanchita Agarwal, Anna Kepley, Fernando Rosete, Yizhong Hu, X Edward Guo, Claire L Keating, Emily A DiMango, Elizabeth Shane
Individuals with cystic fibrosis (CF) have lower bone mineral density (BMD) by DXA and are at higher risk of fracture than healthy controls. However, the 2-dimensional measurement of areal BMD (aBMD) provided by DXA is influenced by bone size and the true extent of the bone deficit is unclear. Our objective was to use high-resolution peripheral quantitative computed tomography (HR-pQCT) and individual trabecula segmentation (ITS) analysis to compare volumetric BMD (vBMD), microarchitecture and estimated strength at the distal radius and tibia in 26 young adults with CF and 26 controls matched for age, gender, and race...
November 14, 2017: Bone
https://www.readbyqxmd.com/read/29152666/neuroanatomical-background-and-functional-considerations-for-stereotactic-interventions-in-the-h-fields-of-forel
#2
REVIEW
Clemens Neudorfer, Mohammad Maarouf
The H fields of Forel constitute an intricate neuroanatomical structure that occupies a central position within the posterior subthalamus. Anatomically, it features a dense concentration of fiber bundles including corticofugal, pallidothalamic, cerebellothalamic and other projections that connect functionally relevant areas of the brain. Functionally, the fields of Forel are embedded within the cortico-striato-thalamo-cortical circuit and constitute the main link between the striatopallidal system and the thalamocortical network...
November 20, 2017: Brain Structure & Function
https://www.readbyqxmd.com/read/29150979/anterior-thalamic-nuclei-lesions-have-a-greater-impact-than-mammillothalamic-tract-lesions-on-the-extended-hippocampal-system
#3
Brook A L Perry, Stephanie A Mercer, Sophie C Barnett, Jungah Lee, John C Dalrymple-Alford
The anterior thalamic nuclei (ATN), mammillary bodies and their interconnecting fiber tract, the mammillothalamic tract (MTT), are important components of an extended hippocampal circuit for episodic memory. In humans, damage to the MTT or ATN in many disorders is associated with severe anterograde amnesia and it is assumed that their influence on memory is functionally equivalent. The relative influence of these two structures on memory has not, however, been assessed explicitly. Here, a direct comparison found that only ATN lesions impaired spatial reference memory in rats...
November 18, 2017: Hippocampus
https://www.readbyqxmd.com/read/29150136/associations-between-cortical-thickness-structural-connectivity-and-severity-of-dimensional-bulimia-nervosa-symptomatology
#4
Margaret L Westwater, Jakob Seidlitz, Kelly M J Diederen, Sarah Fischer, James C Thompson
Bulimia nervosa (BN) is a psychiatric illness defined by preoccupation with body image (cognitive 'symptoms'), binge eating and compensatory behaviors. Although diagnosed BN has been related to grey matter alterations, characterization of brain structure in women with a range of BN symptoms has not been made. This study examined whether cortical thickness (CT) values scaled with severity of BN cognitions in 33 women with variable BN pathology. We then assessed global structural connectivity (SC) of CT to determine if individual differences in global SC relate to BN symptom severity...
November 11, 2017: Psychiatry Research
https://www.readbyqxmd.com/read/29146466/causal-mapping-of-emotion-networks-in-the-human-brain-framework-and-initial-findings
#5
Julien Dubois, Hiroyuki Oya, J Michael Tyszka, Matthew Howard, Frederick Eberhardt, Ralph Adolphs
Emotions involve many cortical and subcortical regions, prominently including the amygdala. It remains unknown how these multiple network components interact, and it remains unknown how they cause the behavioral, autonomic, and experiential effects of emotions. Here we describe a framework for combining a novel technique, concurrent electrical stimulation with fMRI (es-fMRI), together with a novel analysis, inferring causal structure from fMRI data (causal discovery). We outline a research program for investigating human emotion with these new tools, and provide initial findings from two large resting-state datasets as well as case studies in neurosurgical patients with electrical stimulation of the amygdala...
November 13, 2017: Neuropsychologia
https://www.readbyqxmd.com/read/29146465/more-than-blindsight-case-report-of-a-child-with-extraordinary-visual-capacity-following-perinatal-bilateral-occipital-lobe-injury
#6
Inaki-Carril Mundinano, Juan Chen, Mitchell de Souza, Marc G Sarossy, Marc F Joanisse, Melvyn A Goodale, James A Bourne
Injury to the primary visual cortex (V1, striate cortex) and the geniculostriate pathway in adults results in cortical blindness, abolishing conscious visual perception. Early studies by Larry Weiskrantz and colleagues demonstrated that some patients with an occipital-lobe injury exhibited a degree of unconscious vision and visually-guided behaviour within the blind field. A more recent focus has been the observed phenomenon whereby early-life injury to V1 often results in the preservation of visual perception in both monkeys and humans...
November 13, 2017: Neuropsychologia
https://www.readbyqxmd.com/read/29146376/wronger-than-wrong-graded-mapping-of-the-errors-of-an-avatar-in-the-performance-monitoring-system-of-the-onlooker
#7
G Spinelli, G Tieri, E F Pavone, S M Aglioti
EEG studies show that observing errors in one's own or others' actions triggers specific electro-cortical signatures in the onlooker's brain, but whether the brain error-monitoring system operates according to graded or discrete rules is still largely unknown. To explore this issue, we combined immersive virtual reality with EEG recording in participants who observed an avatar reaching-to-grasp a glass from a first-person perspective. The avatar could perform correct or erroneous actions. Erroneous grasps were defined as small or large depending on the magnitude of the trajectory deviation from the to-be-grasped glass...
November 13, 2017: NeuroImage
https://www.readbyqxmd.com/read/29143946/multi-scale-account-of-the-network-structure-of-macaque-visual-cortex
#8
Maximilian Schmidt, Rembrandt Bakker, Claus C Hilgetag, Markus Diesmann, Sacha J van Albada
Cortical network structure has been extensively characterized at the level of local circuits and in terms of long-range connectivity, but seldom in a manner that integrates both of these scales. Furthermore, while the connectivity of cortex is known to be related to its architecture, this knowledge has not been used to derive a comprehensive cortical connectivity map. In this study, we integrate data on cortical architecture and axonal tracing data into a consistent multi-scale framework of the structure of one hemisphere of macaque vision-related cortex...
November 16, 2017: Brain Structure & Function
https://www.readbyqxmd.com/read/29143307/considerations-in-performing-and-analyzing-the-responses-of-cortico-cortical-evoked-potentials-in-stereo-eeg
#9
REVIEW
David Prime, David Rowlands, Steven O'Keefe, Sasha Dionisio
This review aims to highlight key considerations when performing cortico-cortical evoked potentials (CCEPs) using stereo-electroencephalography (SEEG) for network mapping and show its clinical applicability to presurgical evaluations. The parameters for performing stimulation and safety aspects have been investigated in electrocorticography (ECoG) and deep brain stimulation (DBS), but not as extensively in SEEG. A review of current literature was performed, with an attempt made to emphasize practical insights from all modalities of intracranial stimulation...
November 16, 2017: Epilepsia
https://www.readbyqxmd.com/read/29142293/neural-pathways-for-colorectal-control-relevance-to-spinal-cord-injury-and-treatment-a-narrative-review
#10
REVIEW
Brid Callaghan, John B Furness, Ruslan V Pustovit
STUDY DESIGN: Narrative review. OBJECTIVES: The purpose is to review the organisation of the nerve pathways that control defecation and to relate this knowledge to the deficits in colorectal function after SCI. METHODS: A literature review was conducted to identify salient features of defecation control pathways and the functional consequences of damage to these pathways in SCI. RESULTS: The control pathways for defecation have separate pontine centres under cortical control that influence defecation...
November 16, 2017: Spinal Cord
https://www.readbyqxmd.com/read/29142232/tdp-43-misexpression-causes-defects-in-dendritic-growth
#11
Josiah J Herzog, Mugdha Deshpande, Leah Shapiro, Avital A Rodal, Suzanne Paradis
Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Dementia (FTD) share overlapping genetic causes and disease symptoms, and are linked neuropathologically by the RNA binding protein TDP-43 (TAR DNA binding protein-43 kDa). TDP-43 regulates RNA metabolism, trafficking, and localization of thousands of target genes. However, the cellular and molecular mechanisms by which dysfunction of TDP-43 contributes to disease pathogenesis and progression remain unclear. Severe changes in the structure of neuronal dendritic arbors disrupt proper circuit connectivity, which in turn could contribute to neurodegenerative disease...
November 15, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29141024/quantifying-indices-of-short-and-long-range-white-matter-connectivity-at-each-cortical-vertex
#12
Maria Carmela Padula, Marie Schaer, Elisa Scariati, A Kadir Mutlu, Daniela Zöller, Maude Schneider, Stephan Eliez
Several neurodevelopmental diseases are characterized by impairments in cortical morphology along with altered white matter connectivity. However, the relationship between these two measures is not yet clear. In this study, we propose a novel methodology to compute and display metrics of white matter connectivity at each cortical point. After co-registering the extremities of the tractography streamlines with the cortical surface, we computed two measures of connectivity at each cortical vertex: the mean tracts' length, and the proportion of short- and long-range connections...
2017: PloS One
https://www.readbyqxmd.com/read/29140370/mandibular-bone-structure-analysis-using-cone-beam-computed-tomography-vs-primary-implant-stability-an-ex-vivo-study
#13
Ruben Pauwels, Somchai Sessirisombat, Soontra Panmekiate
PURPOSE: To evaluate the relationship between mandibular bone structure parameters measured on preimplant cone beam computed tomography (CBCT) images and primary implant stability. MATERIALS AND METHODS: Twenty-one hemimandibles were scanned on the 3D Accuitomo 170 CBCT. Next, an implant was placed in each hemimandible, after which insertion torque and implant stability quotient (ISQ) measurements were acquired. The following measurements were performed on the preimplant CBCT scans: bone surface, bone volume, fractal dimension, connectivity, trabecular thickness and spacing, and skeleton analysis...
November 2017: International Journal of Oral & Maxillofacial Implants
https://www.readbyqxmd.com/read/29139049/feedforward-architectures-driven-by-inhibitory-interactions
#14
Yazan N Billeh, Michael T Schaub
Directed information transmission is paramount for many social, physical, and biological systems. For neural systems, scientists have studied this problem under the paradigm of feedforward networks for decades. In most models of feedforward networks, activity is exclusively driven by excitatory neurons and the wiring patterns between them, while inhibitory neurons play only a stabilizing role for the network dynamics. Motivated by recent experimental discoveries of hippocampal circuitry, cortical circuitry, and the diversity of inhibitory neurons throughout the brain, here we illustrate that one can construct such networks even if the connectivity between the excitatory units in the system remains random...
November 14, 2017: Journal of Computational Neuroscience
https://www.readbyqxmd.com/read/29137413/abnormal-neural-activities-of-directional-brain-networks-in-patients-with-long-term-bilateral-hearing-loss
#15
Long-Chun Xu, Gang Zhang, Yue Zou, Min-Feng Zhang, Dong-Sheng Zhang, Hua Ma, Wen-Bo Zhao, Guang-Yu Zhang
The objective of the study is to provide some implications for rehabilitation of hearing impairment by investigating changes of neural activities of directional brain networks in patients with long-term bilateral hearing loss. Firstly, we implemented neuropsychological tests of 21 subjects (11 patients with long-term bilateral hearing loss, and 10 subjects with normal hearing), and these tests revealed significant differences between the deaf group and the controls. Then we constructed the individual specific virtual brain based on functional magnetic resonance data of participants by utilizing effective connectivity and multivariate regression methods...
October 13, 2017: Oncotarget
https://www.readbyqxmd.com/read/29134288/task-relevant-brain-networks-identified-with-simultaneous-pet-mr-imaging-of-metabolism-and-connectivity
#16
Andreas Hahn, Gregor Gryglewski, Lukas Nics, Lucas Rischka, Sebastian Ganger, Helen Sigurdardottir, Chrysoula Vraka, Leo Silberbauer, Thomas Vanicek, Alexander Kautzky, Wolfgang Wadsak, Markus Mitterhauser, Markus Hartenbach, Marcus Hacker, Siegfried Kasper, Rupert Lanzenberger
Except for task-specific functional MRI, the vast majority of imaging studies assessed human brain function at resting conditions. However, tracking task-specific neuronal activity yields important insight how the brain responds to stimulation. We specifically investigated changes in glucose metabolism, functional connectivity and white matter microstructure during task performance using several recent methodological advancements. Opening the eyes and right finger tapping had elicited an increased glucose metabolism in primary visual and motor cortices, respectively...
November 13, 2017: Brain Structure & Function
https://www.readbyqxmd.com/read/29130824/longitudinal-structural-and-functional-differences-between-proportional-and-poor-motor-recovery-after-stroke
#17
Adrian G Guggisberg, Pierre Nicolo, Leonardo G Cohen, Armin Schnider, Ethan R Buch
BACKGROUND: Evolution of motor function during the first months after stroke is stereotypically bifurcated, consisting of either recovery to about 70% of maximum possible improvement ("proportional recovery, PROP") or in little to no improvement ("poor recovery, POOR"). There is currently no evidence that any rehabilitation treatment will prevent POOR and favor PROP. OBJECTIVE: To perform a longitudinal and multimodal assessment of functional and structural changes in brain organization associated with PROP...
November 1, 2017: Neurorehabilitation and Neural Repair
https://www.readbyqxmd.com/read/29129406/neuropeptide-y-y2-antagonist-treated-ovariectomized-mice-exhibit-greater-bone-mineral-density
#18
K L Seldeen, P G Halley, C H Volmar, M A Rodríguez, M Hernandez, M Pang, S K Carlsson, L J Suva, C Wahlestedt, B R Troen, S P Brothers
Osteoporosis, a disease characterized by progressive bone loss and increased risk of fracture, often results from menopausal loss of estrogen in women. Neuropeptide Y has been shown to negatively regulate bone formation, with amygdala specific deletion of the Y2 receptor resulting in increased bone mass in mice. In this study, ovariectomized (OVX) mice were injected once daily with JNJ-31020028, a brain penetrant Y2 receptor small molecule antagonist to determine the effects on bone formation. Antagonist treated mice had reduced weight and showed increased whole-body bone mineral density compared to vehicle-injected mice...
November 7, 2017: Neuropeptides
https://www.readbyqxmd.com/read/29127718/-frontal-eye-field-in-prosimian-galagos-intracortical-microstimulation-and-tracing-studies
#19
Iwona Stepniewska, Pierre Pouget, Jon H Kaas
The frontal eye field (FEF) in prosimian primates was identified as a small cortical region, above and anterior to the anterior frontal sulcus, from which saccadic eye movements were evoked with electrical stimulation. Tracer injections revealed FEF connections with cortical and subcortical structures participating in higher order visual processing. Ipsilateral cortical connections were the densest with adjoining parts of the dorsal premotor and prefrontal cortex (PFC). Label in a region corresponding to supplementary eye field (SEF) of other primates, suggests the existence of SEF in galagos...
November 11, 2017: Journal of Comparative Neurology
https://www.readbyqxmd.com/read/29126650/plasticity-in-the-auditory-system
#20
REVIEW
Dexter R F Irvine
Over the last 30 years a wide range of manipulations of auditory input and experience have been shown to result in plasticity in auditory cortical and subcortical structures. The time course of plasticity ranges from very rapid stimulus-specific adaptation to longer-term changes associated with, for example, partial hearing loss or perceptual learning. Evidence for plasticity as a consequence of these and a range of other manipulations of auditory input and/or its significance is reviewed, with an emphasis on plasticity in adults and in the auditory cortex...
October 31, 2017: Hearing Research
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