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https://www.readbyqxmd.com/read/28088660/processes-of-anticipatory-postural-adjustment-and-step-movement-of-gait-initiation
#1
Hiroki Mizusawa, Yasutomo Jono, Yasuyuki Iwata, Atsushi Kinoshita, Koichi Hiraoka
The purpose of this study was to elucidate whether the anticipatory postural adjustment (APA) and focal step movement of gait initiation are produced as a single process or different processes and whether the APA receives an inhibitory drive from the ongoing stop process of gait initiation. Healthy humans initiated gait in response to a first visual cue that instructed the initial swing leg. In some trials, a switch or stop cue was also provided after the first cue. When the stop cue was provided, participants withheld gait initiation...
January 12, 2017: Human Movement Science
https://www.readbyqxmd.com/read/28087602/novel-application-of-3d-contrast-enhanced-cmr-to-define-fibrotic-structure-of-the-human-sinoatrial-node-in-vivo
#2
Thomas A Csepe, Jichao Zhao, Lidiya V Sul, Yufeng Wang, Brian J Hansen, Ning Li, Anthony J Ignozzi, Anna Bratasz, Kimerly A Powell, Ahmet Kilic, Peter J Mohler, Paul M L Janssen, John D Hummel, Orlando P Simonetti, Vadim V Fedorov
AIMS: The adult human sinoatrial node (SAN) has a specialized fibrotic intramural structure (35-55% fibrotic tissue) that provides mechanical and electrical protection from the surrounding atria. We hypothesize that late gadolinium-enhanced cardiovascular magnetic resonance (LGE-CMR) can be applied to define the fibrotic human SAN structure in vivo. METHODS AND RESULTS: LGE-CMR atrial scans of healthy volunteers (n olu, 23-52 y.o.) using a 3 Tesla magnetic resonance imaging system with a spatial resolution of 1...
January 13, 2017: European Heart Journal Cardiovascular Imaging
https://www.readbyqxmd.com/read/28087445/distinct-subcomponents-of-mouse-retinal-ganglion-cell-receptive-fields-are-differentially-altered-by-light-adaptation
#3
C S Cowan, J Sabharwal, R L Seilheimer, S M Wu
The remarkable dynamic range of vision is facilitated by adaptation of retinal sensitivity to ambient lighting conditions. An important mechanism of sensitivity adaptation is control of the spatial and temporal window over which light is integrated. The retina accomplishes this by switching between parallel synaptic pathways with differing kinetics and degrees of synaptic convergence. However, the relative shifts in spatial and temporal integration are not well understood - particularly in the context of the antagonistic spatial surround...
January 10, 2017: Vision Research
https://www.readbyqxmd.com/read/28087408/effects-of-loading-concentration-blood-and-synovial-fluid-on-antibiotic-release-and-anti-biofilm-activity-of-bone-cement-beads
#4
Devendra Dusane, Scott Diamond, Cory Knecht, Nicholas Farrar, Casey Peters, Robert Howlin, Matthew Swearingen, Jason Calhoun, Roger D Plaut, Tanya Nocera, Jeffrey Granger, Paul Stoodley
Antibiotic loaded cement beads are commonly used for the treatment of biofilm related orthopaedic periprosthetic infections; however the effects of antibiotic loading and exposure of beads to body fluids on release kinetics are unclear. The purpose of this study was to determine the effects of (i) antibiotic loading density (ii) loading amount (iii) material type and (iv) exposure to body fluids (blood or synovial fluid) on release kinetics and efficacy of antibiotics against planktonic and lawn biofilm bacteria...
January 10, 2017: Journal of Controlled Release: Official Journal of the Controlled Release Society
https://www.readbyqxmd.com/read/28081593/percutaneous-cryoablation-for-hepatocellular-carcinoma
#5
Kyoung Doo Song
Local ablation therapy is considered as a conventional treatment option for patients with early stage hepatocellular carcinoma (HCC). Although radiofrequency (RF) ablation is widely used for HCC, the use of cryoablation has been increasing as newer and safer cryoablation systems have developed. The thermodynamic mechanism of freezing and thawing used in cryoablation is the Joule-Thomson effect. Cryoablation destroys tissue via direct tissue destruction and vascular-related injury. A few recent comparative studies have shown that percutaneous cryoablation for HCCs is comparable to percutaneous RF ablation in terms of long term therapeutic outcomes and complications...
December 2016: Clinical and Molecular Hepatology
https://www.readbyqxmd.com/read/28081581/differences-in-gene-expression-and-gene-associations-in-epicardial-fat-compared-to-subcutaneous-fat
#6
J Yim, S W Rabkin
Epicardial adipose tissue (EAT) plays a role in cardiac physiology and may contribute to the development of coronary artery disease. Our objective was to determine whether there was a significant difference in gene expression in EAT compared to subcutaneous adipose tissue (SAT) and to identify potential relationships. MEDLINE and EMBASE were searched using the key terms "Epicardial Adipose Tissue" or "Epicardial Fat" in combination with "RNA", "mRNA", or "gene". The entry criteria were studies that presented primary data including expression levels of mRNA in human EAT compared with SAT and an expression of variance (SD)...
January 12, 2017: Hormone and Metabolic Research, Hormon- und Stoffwechselforschung, Hormones et Métabolisme
https://www.readbyqxmd.com/read/28081365/visualizing-arsenate-reactions-and-encapsulation-in-a-single-zero-valent-iron-nanoparticle
#7
Lan Ling, Wei-Xian Zhang
A nanostructure-based mechanism is presented on the enrichment, separation and immobilization of arsenic with nanoscale Zero-Valent Iron (nZVI). The As-Fe reactions are studied with Spherical Aberration Corrected Scanning Transmission Electron Microscopy (Cs-STEM). Near atomic-resolution (<1 nm3) electron tomography discovers a thin continuous layer (23±3 Å) of elemental arsenic sandwiched between the iron oxide shell and the zero-valent iron core. This points to a unique mechanism of nano-encapsulation and proves that the outer layer, especially the Fe(0)/oxide interface is the edge of the As-Fe reactions...
January 12, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28080113/higher-order-cognitive-control-in-dual-tasks-evidence-from-task-pair-switching
#8
Patricia Hirsch, Sophie Nolden, Iring Koch
In the present study, we combined the psychological refractory period (PRP) paradigm with a novel task-pair switching logic which enabled us to isolate performance costs occurring at the global level of task-pairs. In Experiment 1, in which we used conceptually overlapping responses for Task 1 (T1) and Task 2 (T2), we generated 3 task-pairs by combining 1 of 3 visual tasks (T1) with an auditory task (T2). In addition to worse performance after a short SOA than a long SOA (i.e., PRP effect), we found impaired performance in n - 1 task-pair switches as compared to n - 1 task-pair repetitions (i...
January 12, 2017: Journal of Experimental Psychology. Human Perception and Performance
https://www.readbyqxmd.com/read/28079651/branch-retinal-vein-occlusion-secondary-to-a-retinal-arteriolar-macroaneurysm-a-novel-mechanism-supported-by-multimodal-imaging
#9
Yi Chen, Simon D M Chen, Fred K Chen
BACKGROUND/PURPOSE: To report a case of a branch retinal vein occlusion secondary to a retinal arteriolar macroaneurysm (RAM). METHODS: Retrospective case report describing examination findings, treatment outcome and unique multimodal imaging features demonstrated on fluorescein angiography, optical coherence tomography, optical coherence tomography angiography and adaptive optics photography of the retinal vessels and RAM. RESULTS: A 61-year-old man presented with 20/200 vision in the right eye because of a branch retinal vein occlusion secondary to a RAM...
January 10, 2017: Retinal Cases & Brief Reports
https://www.readbyqxmd.com/read/28078884/construction-of-three-dimensional-hemin-functionalized-graphene-hydrogel-with-high-mechanical-stability-and-adsorption-capacity-for-enhancing-photodegradation-of-methylene-blue
#10
Yuewu Zhao, Yuanjian Zhang, Anran Liu, Zhenzhen Wei, Songqin Liu
A three-dimensional hemin-functionalized graphene hydrogel (Hem/GH) was prepared by a facile self-assembly approach. The as-prepared Hem/GH showed good mechanical strength with a storage modulus of 609-642 kPa and a high adsorption capacity to organic dye contaminants (341 mg g-1 for rhodamine B). Moreover, Hem/GH could be used as photosensitizer for photocatalytic degradation of organic dyes, and showed superior photodegradation activity of methylene blue (MB) with respect to the counterparts such as graphene hydrogel (GH) and commercial catalyst P25...
January 12, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28078359/in-touch-with-mental-rotation-interactions-between-mental-and-tactile-rotations-and-motor-responses
#11
Johannes Lohmann, Bettina Rolke, Martin V Butz
Although several process models have described the cognitive processing stages that are involved in mentally rotating objects, the exact nature of the rotation process itself remains elusive. According to embodied cognition, cognitive functions are deeply grounded in the sensorimotor system. We thus hypothesized that modal rotation perceptions should influence mental rotations. We conducted two studies in which participants had to judge if a rotated letter was visually presented canonically or mirrored. Concurrently, participants had to judge if a tactile rotation on their palm changed direction during the trial...
January 11, 2017: Experimental Brain Research. Experimentelle Hirnforschung. Expérimentation Cérébrale
https://www.readbyqxmd.com/read/28078077/a-novel-method-for-the-quantification-of-fatty-infiltration-in-skeletal-muscle
#12
Nicole K Biltz, Gretchen A Meyer
BACKGROUND: Fatty infiltration of the skeletal muscle is a common but poorly understood feature of many myopathies. It is best described in human muscle, where non-invasive imaging techniques and representative histology have been optimized to view and quantify infiltrating fat. However, human studies are limited in their ability to identify cellular and molecular mechanisms regulating fatty infiltration, a likely prerequisite to developing targeted interventions. As mechanistic investigations move to small animals, studies may benefit from new or adapted imaging tools optimized for high resolution and whole muscle quantification...
2017: Skeletal Muscle
https://www.readbyqxmd.com/read/28077877/integration-of-temporal-and-spatial-patterning-generates-neural-diversity
#13
Ted Erclik, Xin Li, Maximilien Courgeon, Claire Bertet, Zhenqing Chen, Ryan Baumert, June Ng, Clara Koo, Urfa Arain, Rudy Behnia, Alberto Del Valle Rodriguez, Lionel Senderowicz, Nicolas Negre, Kevin P White, Claude Desplan
In the Drosophila optic lobes, 800 retinotopically organized columns in the medulla act as functional units for processing visual information. The medulla contains over 80 types of neuron, which belong to two classes: uni-columnar neurons have a stoichiometry of one per column, while multi-columnar neurons contact multiple columns. Here we show that combinatorial inputs from temporal and spatial axes generate this neuronal diversity: all neuroblasts switch fates over time to produce different neurons; the neuroepithelium that generates neuroblasts is also subdivided into six compartments by the expression of specific factors...
January 11, 2017: Nature
https://www.readbyqxmd.com/read/28077721/temporal-expectations-guide-dynamic-prioritization-in-visual-working-memory-through-attenuated-%C3%AE-oscillations
#14
Freek van Ede, Marcel Niklaus, Anna C Nobre
: Although working memory is generally considered a highly dynamic mnemonic store, popular laboratory tasks used to understand its psychological and neural mechanisms (such as change detection and continuous reproduction) often remain relatively "static," involving the retention of a set number of items throughout a shared delay interval. In the current study, we investigated visual working memory in a more dynamic setting, and assessed the following: (1) whether internally guided temporal expectations can dynamically and reversibly prioritize individual mnemonic items at specific times at which they are deemed most relevant; and (2) the neural substrates that support such dynamic prioritization...
January 11, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28077711/phase-amplitude-coupling-and-long-range-phase-synchronization-reveal-frontotemporal-interactions-during-visual-working-memory
#15
Jonathan Daume, Thomas Gruber, Andreas K Engel, Uwe Friese
: It has been suggested that cross-frequency phase-amplitude coupling (PAC), particularly in temporal brain structures, serves as a neural mechanism for coordinated working memory storage. In this magnetoencephalography study, we show that during visual working memory maintenance, temporal cortex regions, which exhibit enhanced PAC, interact with prefrontal cortex via enhanced low-frequency phase synchronization. Healthy human participants were engaged in a visual delayed match-to-sample task with pictures of natural objects...
January 11, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28077665/spatial-cognition-in-a-virtual-reality-home-cage-extension-for-freely-moving-rodents
#16
Ursula Kaupert, Kay Thurley, Katja Frei, Francesco Bagorda, Alexej Schatz, Gilad Tocker, Sophia Rapoport, Dori Derdikman, York Winter
Virtual reality environments are part of a powerful tool set to investigate brain mechanisms of behavior in animals. For this, animals are mostly head-fixed or in a harness, and training for cognitively more complex VR paradigms is time consuming. A virtual reality apparatus allowing free animal movement and 24/7 operator-independent training of tasks would enable many new applications. Key prospective usages include brain imaging in behaving animals carrying a miniaturized mobile device such as a fluorescence microscope, or an optetrode...
January 11, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/28077512/differential-contribution-of-low-and-high-level-image-content-to-eye-movements-in-monkeys-and-humans
#17
Niklas Wilming, Tim C Kietzmann, Megan Jutras, Cheng Xue, Stefan Treue, Elizabeth A Buffalo, Peter König
Oculomotor selection exerts a fundamental impact on our experience of the environment. To better understand the underlying principles, researchers typically rely on behavioral data from humans, and electrophysiological recordings in macaque monkeys. This approach rests on the assumption that the same selection processes are at play in both species. To test this assumption, we compared the viewing behavior of 106 humans and 11 macaques in an unconstrained free-viewing task. Our data-driven clustering analyses revealed distinct human and macaque clusters, indicating species-specific selection strategies...
January 10, 2017: Cerebral Cortex
https://www.readbyqxmd.com/read/28077329/body-schema-plasticity-after-stroke-subjective-and-neurophysiological-correlates-of-the-rubber-hand-illusion
#18
Roberto Llorens, Adrián Borrego, Priscila Palomo, Ausiàs Cebolla, Enrique Noé, Sergi Bermúdez I Badia, Rosa Baños
Stroke can lead to motor impairments that can affect the body structure and restraint mobility. We hypothesize that brain lesions and their motor sequelae can distort the body schema, a sensorimotor map of body parts and elements in the peripersonal space through which human beings embody the reachable space and ready the body for forthcoming movements. Two main constructs have been identified in the embodiment mechanism: body-ownership, the sense that the body that one inhabits is his/her own, and agency, the sense that one can move and control his/her body...
January 8, 2017: Neuropsychologia
https://www.readbyqxmd.com/read/28076448/igf-1-induces-ghrh-neuronal-axon-elongation-during-early-postnatal-life-in-mice
#19
Lyvianne Decourtye, Erik Mire, Maud Clemessy, Victor Heurtier, Tatiana Ledent, Iain C Robinson, Patrice Mollard, Jacques Epelbaum, Michael J Meaney, Sonia Garel, Yves Le Bouc, Laurent Kappeler
Nutrition during the perinatal period programs body growth. Growth hormone (GH) secretion from the pituitary regulates body growth and is controlled by Growth Hormone Releasing Hormone (GHRH) neurons located in the arcuate nucleus of the hypothalamus. We observed that dietary restriction during the early postnatal period (i.e. lactation) in mice influences postnatal growth by permanently altering the development of the somatotropic axis in the pituitary gland. This alteration may be due to a lack of GHRH signaling during this critical developmental period...
2017: PloS One
https://www.readbyqxmd.com/read/28075612/comparison-of-mechanical-versus-hand-administration-of-iv-contrast-agents-for-pediatric-pulmonary-ct-angiography
#20
Matthew A Zapala, David Zurakowski, Edward Y Lee
OBJECTIVE: The purpose of this study was to assess the difference between mechanical versus hand administration of IV contrast agents on the diagnostic quality of pediatric pulmonary CT angiography (CTA). MATERIALS AND METHODS: A retrospective review of the medical records was performed to detect pediatric patients (≤ 18 years) with pulmonary CTA performed between September 2012 and March 2015. Patients were placed into two cohorts on the basis of the method of contrast administration (mechanical vs hand)...
January 11, 2017: AJR. American Journal of Roentgenology
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