Read by QxMD icon Read

Cortical modeling

F G A Silva, M F S F de Moura, N Dourado, J Xavier, F A M Pereira, J J L Morais, M I R Dias, P J Lourenço, F M Judas
Fracture characterization of human cortical bone under mode II loading was analyzed using a miniaturized version of the end-notched flexure test. A data reduction scheme based on crack equivalent concept was employed to overcome uncertainties on crack length monitoring during the test. The crack tip shear displacement was experimentally measured using digital image correlation technique to determine the cohesive law that mimics bone fracture behavior under mode II loading. The developed procedure was validated by finite element analysis using cohesive zone modeling considering a trapezoidal with bilinear softening relationship...
October 25, 2016: Medical & Biological Engineering & Computing
Ximena Corso-Díaz, Charles N de Leeuw, Vivian Alonso, Diana Melchers, Bibiana K Y Wong, René Houtman, Elizabeth M Simpson
BACKGROUND: NR2E1 (Tlx) is an orphan nuclear receptor that regulates the maintenance and self-renewal of neural stem cells, and promotes tumourigenesis. Nr2e1-null mice exhibit reduced cortical and limbic structures and pronounced retinal dystrophy. NR2E1 functions mainly as a repressor of gene transcription in association with the co-repressors atrophin-1, LSD1, HDAC and BCL11A. Recent evidence suggests that NR2E1 also acts as an activator of gene transcription. However, co-activator complexes that interact with NR2E1 have not yet been identified...
October 26, 2016: BMC Genomics
Ian Gopal Gould, Philbert Tsai, David Kleinfeld, Andreas Linninger
The cortical angioarchitecture is a key factor in controlling cerebral blood flow and oxygen metabolism. Difficulties in imaging the complex microanatomy of the cortex have so far restricted insight about blood flow distribution in the microcirculation. A new methodology combining advanced microscopy data with large scale hemodynamic simulations enabled us to quantify the effect of the angioarchitecture on the cerebral microcirculation. High-resolution images of the mouse primary somatosensory cortex were input into with a comprehensive computational model of cerebral perfusion and oxygen supply ranging from the pial vessels to individual brain cells...
October 10, 2016: Journal of Cerebral Blood Flow and Metabolism
Martin Larsson, Grazyna Lietzau, David Nathanson, Claes-Göran Östenson, Carina Mallard, Maria E Johansson, Thomas Nyström, Cesare Patrone, Vladimer Darsalia
Type 2 diabetic (T2D) patients often develop early cognitive and sensorimotor impairments. The pathophysiological mechanisms behind these problems are largely unknown. Recent studies demonstrate that dysfunctional γ-Aminobutyric acid (GABAergic) neurons are involved in age-related cognitive decline. We hypothesized that similar, but earlier dysfunction is taking place under T2D in the neocortex and striatum (two brain areas important for cognition and sensorimotor functions). We also hypothesized that the T2D-induced effects are pharmacologically reversible by anti-diabetic drugs targeting the glucagon-like peptide-1 receptor (GLP-1R)...
October 25, 2016: Bioscience Reports
Catherine Okoukoni, David M Randolph, Emory R McTyre, Andy Kwok, Ashley A Weaver, A William Blackstock, Michael T Munley, Jeffrey S Willey
BACKGROUND AND PURPOSE: Anal cancer patients treated with radiation therapy (RT) have an increased risk of hip fractures after treatment. The mechanism of these fractures is unknown; however, femoral fractures have been correlated with cortical bone thinning. The objective of this study was to assess early changes in cortical bone thickness at common sites of femoral fracture in anal cancer patients treated with intensity modulated radiation therapy (IMRT). MATERIALS AND METHODS: RT treatment plans and computed tomography (CT) scans from 23 anal cancer patients who underwent IMRT between November 2012 and December 2014 were retrospectively reviewed...
October 22, 2016: Bone
Kavita Singh, Richa Trivedi, Seenu Haridas, Kailash Manda, Subash Khushu
Mild traumatic brain injury (mTBI) is the most common form of TBI (70-90%) with consequences of anxiety-like behavioral alterations in approximately 23% of mTBI cases. This study aimed to assess whether mTBI-induced anxiety-like behavior is a consequence of neurometabolic alterations. mTBI was induced using a weight drop model to simulate mild human brain injury in rodents. Based on injury induction and dosage of anesthesia, four animal groups were included in this study: (i) injury with anesthesia (IA); (ii) sham1 (injury only, IO); (iii) sham2 (only anesthesia, OA); and (iv) control rats...
October 25, 2016: NMR in Biomedicine
Bulent Ergin, Michal Heger, Asli Kandil, Cihan Demirci-Tansel, Can Ince
Ischemia/reperfusion (I/R) is one of the main causes of acute kidney injury (AKI), which is characterized by sterile inflammation and oxidative stress. Immune cell activation can provoke overproduction of inflammatory mediators and reactive oxygen species (ROS), leading to perturbation of the microcirculation and tissue oxygenation associated with local and remote tissue injury. This study investigated whether the clinically employed immunosuppressant mycophenolate mofetil (MMF) was able to reduce I/R-induced renal oxygenation defects and oxidative stress by preventing sterile inflammation...
October 25, 2016: Clinical and Experimental Pharmacology & Physiology
A Gouveia, S P Dias, T Santos, H Rocha, C R Coelho, L Ruano, O Galego, M C Diogo, D Seixas, M J Sá, S Batista
OBJECTIVES: To characterize cognitive impairment in primary progressive multiple sclerosis (PPMS) and to correlate the pattern of cognitive deficits with brain magnetic resonance imaging (MRI) volumetric data. MATERIALS AND METHODS: In a multicenter cross-sectional study, we recruited consecutive patients with PPMS as well as age, sex, and education level-matched healthy controls (HC). All participants underwent neuropsychological (NP) assessment, and brain MRI was performed in patients with PPMS for analysis of lesion load, subcortical GM volumes, and regional cortical volumes...
October 24, 2016: Acta Neurologica Scandinavica
Sabine Peters, Jiska S Peper, Anna C K Van Duijvenvoorde, Barbara R Braams, Eveline A Crone
This study tested the relation between cortical-subcortical functional connectivity and alcohol consumption in adolescents using an accelerated longitudinal design, as well as normative developmental patterns for these measures. Participants between ages 8 and 27 completed resting-state neuroimaging scans at two time points separated by two years (N = 274 at T1, N = 231 at T2). In addition, participants between ages 12 and 27 reported on recent and lifetime alcohol use (N = 193 at T1, N = 244 at T2)...
October 23, 2016: Developmental Science
Sava Sakadžić, Mohammad A Yaseen, Rajeshwer Jaswal, Emmanuel Roussakis, Anders M Dale, Richard B Buxton, Sergei A Vinogradov, David A Boas, Anna Devor
The cerebral metabolic rate of oxygen ([Formula: see text]) is an essential parameter for evaluating brain function and pathophysiology. However, the currently available approaches for quantifying [Formula: see text] rely on complex multimodal imaging and mathematical modeling. Here, we introduce a method that allows estimation of [Formula: see text] based on a single measurement modality-two-photon imaging of the partial pressure of oxygen ([Formula: see text]) in cortical tissue. We employed two-photon phosphorescence lifetime microscopy (2PLM) and the oxygen-sensitive nanoprobe PtP-C343 to map the tissue [Formula: see text] distribution around cortical penetrating arterioles...
October 2016: Neurophotonics
Rui Zhang, Lotte Bonde Bertelsen, Christian Flø, Yan Wang, Hans Stødkilde-Jørgensen
BACKGROUND AND PURPOSE: Due to well-developed Circle of Willis in pigs, it is technically challenging to make persistent focal ischemic stroke based on occlusion of cerebral arteries. Endothelin-1 could cause a focal lesion by forcing transient but strong vasoconstriction in the circumscribed injected area. Its use in porcine stroke model has drawn attention lately. However, all the porcine endothelin-1 induced models were euthanized soon after surgery. Whether the brain lesion is persistent, and whether they could cause neurological deficit are not known...
October 20, 2016: Neuroscience Letters
P Tenreiro, S Rebelo, F Martins, M Santos, E D Coelho, M Almeida, A P Alves de Matos, O A B da Cruz E Silva
Synaptosomes are isolated nerve terminals. They represent an extremely attractive in vitro model system to study synaptic physiology since they preserve morphological and functional characteristics of the synapse. As such they have been used to investigate synaptic dysfunctions associated with neuropathologies like Alzheimer's disease. In the present work two simple methodologies for isolating synaptosomal-enriched fractions were compared for the first time. The starting points of both protocols were rat cortical or hippocampal homogenized tissues that underwent several differential centrifugation steps followed by a final purification of synaptosomal-enriched fractions using either a Percoll gradient or a Sucrose gradient...
October 19, 2016: Analytical Biochemistry
L M Rueda-Delgado, E Solesio-Jofre, D Mantini, P Dupont, A Daffertshofer, S P Swinnen
The neural network and the task-dependence of (local) activity changes involved in bimanual coordination are well documented. However, much less is known about the functional connectivity within this neural network and its modulation according to manipulations of task complexity. Here, we assessed neural activity via high-density electroencephalography, focussing on changes of activity in the beta frequency band (~15-30Hz) across the motor network in 26 young adult participants (19-29 years old). We investigated how network connectivity was modulated with task difficulty and errors of performance during a bimanual visuomotor movement consisting of dial rotation according to three different ratios of speed: an isofrequency movement (1:1), a non-isofrequency movement with the right hand keeping the fast pace (1:3), and the converse ratio with the left hand keeping the fast pace (3:1)...
October 19, 2016: NeuroImage
Gordon X Wang, Stephen J Smith, Philippe Mourrain
The distribution of proteins within sub-synaptic compartments is an essential aspect of their neurological function. Current methodology such as electron microscopy (EM) and super-resolution imaging techniques can provide precise localization of proteins, but are often limited to a small number of one-time observations with narrow spatial and molecular coverage. The diversity of synaptic proteins and synapse types demands synapse analysis on a scale that is prohibitive with current methods. Here, we demonstrate SubSynMAP, a fast, multiplexed sub-synaptic protein analysis method using wide-field data from deconvolution array tomography (ATD)...
October 22, 2016: ELife
E Saralidze, L Khuchua, I Kobaidze
The interaction between different brain structures could be crucial to predicting seizure occurrence, threshold and spread. Moreover, the sleep-wake cycle and electrical activity of brain structures in different phases of sleep could significantly affect the pattern and extent of seizure spread, and therefore the characteristics of epileptic activity. In this animal model using 15 Wistar rats, we show that the duration of hippocampal seizures, induced by electrical stimulation of the hippocampus, is significantly increased during slow sleep...
September 2016: Georgian Medical News
Juan A Sanchis-Gimeno, Susanna Llido, David Guede, Francisco Martinez-Soriano, Jose R Caeiro, Esther Blanco-Perez
BACKGROUND CONTEXT: To date, no information about the cortical bone microstructural properties in atlas vertebrae with posterior arch defects has been reported. PURPOSE: To test if there is an increased cortical bone thickening in atlases with Type A posterior atlas arch defects in an experimental model. STUDY DESIGN: Micro-computed tomography study on cadaveric atlas vertebrae. METHODS: We analyzed the cortical bone thickness, the cortical volume, and the medullary volume (SkyScan 1172 Bruker micro-CT NV, Kontich, Belgium) in cadaveric dry vertebrae with a Type A atlas arch defect and normal control vertebrae...
October 18, 2016: Spine Journal: Official Journal of the North American Spine Society
Prashanthi Vemuri, David S Knopman, Clifford R Jack, Emily S Lundt, Stephen D Weigand, Samantha M Zuk, Kaely B Thostenson, Robert I Reid, Kejal Kantarci, Yelena Slinin, Kamakshi Lakshminarayan, Cynthia S Davey, Anne Murray
BACKGROUND: Chronic kidney disease (CKD) studies have reported variable prevalence of brain pathologies, in part due to low inclusion of participants with moderate to severe CKD. OBJECTIVE: To measure the association between kidney function biomarkers and brain MRI findings in CKD. METHODS: In the BRINK (BRain IN Kidney Disease) study, MRI was used to measure gray matter volumes, cerebrovascular pathologies (white matter hyperintensity (WMH), infarctions, microhemorrhages), and microstructural changes using diffusion tensor imaging (DTI)...
October 19, 2016: Journal of Alzheimer's Disease: JAD
O Laporta-Hoyos, J Ballester-Plané, P Póo, A Macaya, M Meléndez-Plumed, E Vázquez, I Delgado, L Zubiaurre-Elorza, V L Botellero, A Narberhaus, E Toro-Tamargo, D Segarra, R Pueyo
PURPOSE: Quality of life (QOL) is a key outcome for people with cerebral palsy (CP), and executive functioning is an important predictor of QOL in other health-related conditions. Little is known about this association in CP or about its neural substrate. We aim to analyze the influence of executive functioning (including cognitive flexibility) as well as that of other psychological, motor, communication and socioeconomic variables on QOL and to identify neuroanatomical areas related to QOL in adolescents and adults with CP...
October 20, 2016: Quality of Life Research
Uta Hanning, Andreas Roesler, Annette Peters, Klaus Berger, Bernhard T Baune
While MRI brain changes have been related to mortality during ageing, the role of inflammation in this relationship remains poorly understood. Hence, this study aimed to investigate the impact of MRI changes on all-cause mortality and the mediating role of cytokines. All-cause mortality was evaluated in 268 community dwelling elderly (age 65-83 years) in the MEMO study (Memory and Morbidity in Augsburg elderly). MRI markers of brain atrophy and cerebral small vessel disease (SVD), C-reactive protein (CRP) and a panel of cytokines in serum were assessed...
October 20, 2016: Age (2005-)
Alba Di Pardo, Enrico Amico, Vittorio Maglione
Huntington Disease (HD) is a genetic neurodegenerative disorder characterized by broad types of cellular and molecular dysfunctions that may affect both neuronal and non-neuronal cell populations. Among all the molecular mechanisms underlying the complex pathogenesis of the disease, alteration of sphingolipids has been identified as one of the most important determinants in the last years. In the present study, besides the purpose of further confirming the evidence of perturbed metabolism of gangliosides GM1, GD1a, and GT1b the most abundant cerebral glycosphingolipids, in the striatal and cortical tissues of HD transgenic mice, we aimed to test the hypothesis that abnormal levels of these lipids may be found also in the corpus callosum white matter, a ganglioside-enriched brain region described being dysfunctional early in the disease...
2016: Frontiers in Neuroscience
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"