keyword
MENU ▼
Read by QxMD icon Read
search

Blood Oxygenation Level Dependent

keyword
https://www.readbyqxmd.com/read/28099241/fmri-with-central-vision-loss-effects-of-fixation-locus-and-stimulus-type
#1
Tina Plank, Jozef Frolo, Sabine Brandl-Rühle, Agnes B Renner, Herbert Jägle, Mark W Greenlee
PURPOSE: In patients with central visual field scotomata, a large part of visual cortex is not adequately stimulated. Patients often use a new eccentric fixation area on intact peripheral retina ("preferred retinal locus"-PRL) that functions as a pseudo-fovea. We used functional magnetic resonance imaging (fMRI) to examine whether stimulating this pseudo-fovea leads to increased activation or altered activation patterns in visual cortex in comparison to stimulating a comparable peripheral area in the opposite hemifield (OppPRL)...
January 18, 2017: Optometry and Vision Science: Official Publication of the American Academy of Optometry
https://www.readbyqxmd.com/read/28098938/towards-prognostic-biomarkers-from-bold-fluctuations-to-differentiate-a-first-epileptic-seizure-from-new-onset-epilepsy
#2
Lalit Gupta, Rick Janssens, Mariëlle C G Vlooswijk, Rob P W Rouhl, Anton de Louw, Albert P Aldenkamp, Shrutin Ulman, René M H Besseling, Paul A M Hofman, Vivianne H van Kranen-Mastenbroek, Danny M Hilkman, Jacobus F A Jansen, Walter H Backes
OBJECTIVE: The diagnosis of epilepsy cannot be reliably made prior to a patient's second seizure in most cases. Therefore, adequate diagnostic tools are needed to differentiate subjects with a first seizure from those with a seizure preceding the onset of epilepsy. The objective was to explore spontaneous blood oxygen level-dependent (BOLD) fluctuations in subjects with a first-ever seizure and patients with new-onset epilepsy (NOE), and to find characteristic biomarkers for seizure recurrence after the first seizure...
January 18, 2017: Epilepsia
https://www.readbyqxmd.com/read/28089970/spatial-working-memory-impairment-in-patients-with-non-neuropsychiatric-systemic-lupus-erythematosus-a-blood-oxygen-level-dependent-functional-magnetic-resonance-imaging-study
#3
Chun-Min Zhu, Ye Ma, Lei Xie, Jin-Zhuang Huang, Zong-Bo Sun, Shou-Xing Duan, Zhi-Rong Lin, Jing-Jing Yin, Hong-Bo Le, Dan-Miao Sun, Wen-Can Xu, Shu-Hua Ma
OBJECTIVE: Using ethology and functional magnetic resonance imaging (fMRI) to explore mild cognitive dysfunction and spatial working memory (WM) impairment in patients with systemic lupus erythematosus (SLE) without overt neuropsychiatric symptoms (non-NPSLE) and to study whether any clinical biomarkers could serve as predictors of brain dysfunction in this disease. METHODS: Eighteen non-NPSLE patients and 18 matched subjects were all tested using the Montreal cognitive assessment scale test and scanned using blood-oxygen-level dependent fMRI while performing the n-back task to investigate the activation intensity of some cognition-related areas...
January 15, 2017: Journal of Rheumatology
https://www.readbyqxmd.com/read/28089903/advances-in-mr-angiography-with-7t-mri-from-microvascular-imaging-to-functional-angiography
#4
Chan-A Park, Chang-Ki Kang, Young-Bo Kim, Zang-Hee Cho
Over the past few decades, vascular flow-dependent imaging techniques have proven to be effective for the visualization of large vessel diseases. However, these approaches are unlikely to be efficacious for small vessels because the affected small vessels cannot always be visualized directly, owing to a lack of detection sensitivity. Recently, many researchers have introduced state-of-the-art imaging techniques to visualize cerebral microvessels using ultra-high-field (UHF) magnetic resonance angiography (MRA)...
January 12, 2017: NeuroImage
https://www.readbyqxmd.com/read/28089677/global-signal-regression-acts-as-a-temporal-downweighting-process-in-resting-state-fmri
#5
Alican Nalci, Bhaskar D Rao, Thomas T Liu
In resting-state functional MRI (rsfMRI), the correlation between blood oxygenation level dependent (BOLD) signals across different brain regions is used to estimate the functional connectivity of the brain. This approach has led to the identification of a number of resting-state networks, including the default mode network (DMN) and the task positive network (TPN). Global signal regression (GSR) is a widely used pre-processing step in rsfMRI that has been shown to improve the spatial specificity of the estimated resting-state networks...
January 9, 2017: NeuroImage
https://www.readbyqxmd.com/read/28089656/how-do-antidepressants-influence-the-bold-signal-in-the-developing-brain
#6
REVIEW
Julia J Harris, Clare Reynell
Depression is a highly prevalent life-threatening disorder, with its first onset commonly occurring during adolescence. Adolescent depression is increasingly being treated with antidepressants, such as fluoxetine. The use of medication during this sensitive period of physiological and cognitive brain development produces neurobiological changes, some of which may outlast the course of treatment. In this review, we look at how antidepressant treatment in adolescence is likely to alter neurovascular coupling and brain energy use and how these changes, in turn, affect our ability to identify neuronal activity changes between participant groups...
December 21, 2016: Developmental Cognitive Neuroscience
https://www.readbyqxmd.com/read/28081033/performance-aspects-and-physiological-responses-in-male-amateur-boxing-competitions-a-brief-review
#7
Maamer Slimani, Helmi Chaabène, Philip Davis, Emerson Franchini, Karim Chamari
Boxing is one of the most popular striking combat sports in the world. The aim of this review was to present data concerning performance analysis (time-motion and technical/tactical analysis) and physiological responses (i.e., blood lactate concentration [BLC], heart rate and/or oxygen consumption) during novice and elite male simulated and official amateur boxing competitions in any age category. The present review shows that boxing competition is a high-intensity intermittent striking combat sport. Typically, the activity-to-rest ratio was higher in elite (18:1) than novice (9:1) boxers and significant differences were observed between rounds (1 round=16:1, 2 round=8:1, and 3 round=6:1) in novice boxers...
January 4, 2017: Journal of Strength and Conditioning Research
https://www.readbyqxmd.com/read/28080974/how-the-heart-speaks-to-the-brain-neural-activity-during-cardiorespiratory-interoceptive-stimulation
#8
Mahlega S Hassanpour, Lirong Yan, Danny J J Wang, Rachel C Lapidus, Armen C Arevian, W Kyle Simmons, Jamie D Feusner, Sahib S Khalsa
Prominent theories emphasize key roles for the insular cortex in the central representation of interoceptive sensations, but how this brain region responds dynamically to changes in interoceptive state remains incompletely understood. Here, we systematically modulated cardiorespiratory sensations in humans using bolus infusions of isoproterenol, a rapidly acting peripheral beta-adrenergic agonist similar to adrenaline. To identify central neural processes underlying these parametrically modulated interoceptive states, we used pharmacological functional magnetic resonance imaging (phMRI) to simultaneously measure blood-oxygenation-level dependent (BOLD) and arterial spin labelling (ASL) signals in healthy participants...
November 19, 2016: Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
https://www.readbyqxmd.com/read/28077722/higher-heart-rate-variability-is-associated-with-ventromedial-prefrontal-cortex-activity-and-increased-resistance-to-temptation-in-dietary-self-control-challenges
#9
Silvia U Maier, Todd A Hare
: Higher levels of self-control in decision making have been linked to better psychosocial and physical health. A similar link to health outcomes has been reported for heart-rate variability (HRV), a marker of physiological flexibility. Here, we sought to link these two, largely separate, research domains by testing the hypothesis that greater HRV would be associated with better dietary self-control in humans. Specifically, we examined whether total HRV at sedentary rest (measured as the SD of normal-to-normal intervals) can serve as a biomarker for the neurophysiological adaptability that putatively underlies self-controlled behavior...
January 11, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28076368/functional-laterality-of-task-evoked-activation-in-sensorimotor-cortex-of-preterm-infants-an-optimized-3-t-fmri-study-employing-a-customized-neonatal-head-coil
#10
Lukas Scheef, Jurek A Nordmeyer-Massner, Adam Pr Smith-Collins, Nicole Müller, Gaby Stegmann-Woessner, Jacob Jankowski, Jürgen Gieseke, Mark Born, Hermann Seitz, Peter Bartmann, Hans H Schild, Klaas P Pruessmann, Axel Heep, Henning Boecker
BACKGROUND: Functional magnetic resonance imaging (fMRI) in neonates has been introduced as a non-invasive method for studying sensorimotor processing in the developing brain. However, previous neonatal studies have delivered conflicting results regarding localization, lateralization, and directionality of blood oxygenation level dependent (BOLD) responses in sensorimotor cortex (SMC). Amongst the confounding factors in interpreting neonatal fMRI studies include the use of standard adult MR-coils providing insufficient signal to noise, and liberal statistical thresholds, compromising clinical interpretation at the single subject level...
2017: PloS One
https://www.readbyqxmd.com/read/28074492/confirmation-of-resting-state-bold-fluctuations-in-the-human-brainstem-and-spinal-cord-after-identification-and-removal-of-physiological-noise
#11
Shreyas Harita, Patrick W Stroman
PURPOSE: Resting-state functional MRI (rs-fMRI) has been used to investigate networks within the cortex, but its use in the brainstem (BS) and spinal cord (SC) has been limited. This region presents challenges for fMRI, partly because of sources of physiological noise. This study aims to quantify noise contributions to rs-fMRI, and to obtain evidence of resting-state blood oxygenation level-dependent (BOLD) fluctuations. METHODS: Resting-state-fMRI data were obtained from the BS/SC in 16 participants, at 3 Tesla, with T2 -weighted single-shot fast spin-echo imaging...
January 11, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28073651/i-know-i-ve-seen-you-before-distinguishing-recent-single-exposure-based-familiarity-from-pre-existing-familiarity
#12
Sarah I Gimbel, James B Brewer, Anat Maril
This study examines how individuals differentiate recent-single-exposure-based familiarity from pre-existing familiarity. If these are two distinct cognitive processes, are they supported by the same neural bases? This study examines how recent-single-exposure-based familiarity and multiple-previous-exposure-based familiarity are supported and represented in the brain using functional MRI. In a novel approach, we first behaviorally show that subjects can divide retrieval of items in pre-existing memory into judgments of recollection and familiarity...
January 7, 2017: Brain Research
https://www.readbyqxmd.com/read/28072842/fractal-analysis-of-brain-blood-oxygenation-level-dependent-bold-signals-from-children-with-mild-traumatic-brain-injury-mtbi
#13
Olga Dona, Michael D Noseworthy, Carol DeMatteo, John F Connolly
BACKGROUND: Conventional imaging techniques are unable to detect abnormalities in the brain following mild traumatic brain injury (mTBI). Yet patients with mTBI typically show delayed response on neuropsychological evaluation. Because fractal geometry represents complexity, we explored its utility in measuring temporal fluctuations of brain resting state blood oxygen level dependent (rs-BOLD) signal. We hypothesized that there could be a detectable difference in rs-BOLD signal complexity between healthy subjects and mTBI patients based on previous studies that associated reduction in signal complexity with disease...
2017: PloS One
https://www.readbyqxmd.com/read/28060861/predicting-the-multisensory-consequences-of-one-s-own-action-bold-suppression-in-auditory-and-visual-cortices
#14
Benjamin Straube, Bianca M van Kemenade, B Ezgi Arikan, Katja Fiehler, Dirk T Leube, Laurence R Harris, Tilo Kircher
Predictive mechanisms are essential to successfully interact with the environment and to compensate for delays in the transmission of neural signals. However, whether and how we predict multisensory action outcomes remains largely unknown. Here we investigated the existence of multisensory predictive mechanisms in a context where actions have outcomes in different modalities. During fMRI data acquisition auditory, visual and auditory-visual stimuli were presented in active and passive conditions. In the active condition, a self-initiated button press elicited the stimuli with variable short delays (0-417ms) between action and outcome, and participants had to detect the presence of a delay for auditory or visual outcome (task modality)...
2017: PloS One
https://www.readbyqxmd.com/read/28058665/oxidative-stress-and-genotoxicity-of-zinc-oxide-nanoparticles-to-pseudomonas-species-human-promyelocytic-leukemic-hl-60-and-blood-cells
#15
Deepika Soni, Deepa Gandhi, Prashant Tarale, Amit Bafana, R A Pandey, Saravanadevi Sivanesan
In the present study, toxicity of commercial zinc oxide nanoparticles (ZnO NPs) was studied on the bacterium Pseudomonas sp., human promyelocytic leukemia (HL-60) cells, and peripheral blood mononuclear cells (PBMC). The toxicity was assessed by measuring growth, cell viability, and protein expression in bacterial cell. The bacterial growth and viability decreased with increasing concentrations of ZnO NP. Three major proteins, ribosomal protein L1 and L9 along with alkyl hydroperoxides reductase, were upregulated by 1...
January 5, 2017: Biological Trace Element Research
https://www.readbyqxmd.com/read/28052074/distinction-between-neural-and-vascular-bold-oscillations-and-intertwined-heart-rate-oscillations-at-0-1-hz-in-the-resting-state-and-during-movement
#16
Gert Pfurtscheller, Andreas Schwerdtfeger, Clemens Brunner, Christoph Aigner, David Fink, Joana Brito, Marciano P Carmo, Alexandre Andrade
In the resting state, blood oxygen level-dependent (BOLD) oscillations with a frequency of about 0.1 Hz are conspicuous. Whether their origin is neural or vascular is not yet fully understood. Furthermore, it is not clear whether these BOLD oscillations interact with slow oscillations in heart rate (HR). To address these two questions, we estimated phase-locking (PL) values between precentral gyrus (PCG) and insula in 25 scanner-naïve individuals during rest and stimulus-paced finger movements in both hemispheres...
2017: PloS One
https://www.readbyqxmd.com/read/28051026/blood-oxygenation-level-dependent-magnetic-resonance-imaging-of-breast-cancer-correlation-with-carbonic-anhydrase-ix-and-vascular-endothelial-growth-factor
#17
Ying Wang, Min Liu, Mu-Lan Jin
BACKGROUND: Blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI) is a functional MRI technique which involves using the paramagnetic properties of deoxyhemoglobin to image the local tissue oxygen concentration. The purpose of this study was to investigate whether BOLD-MRI could evaluate hypoxia and angiogenesis of breast invasive ductal carcinoma (IDC). METHODS: Ninety-eight female patients with IDC were retrospectively included in this research...
2017: Chinese Medical Journal
https://www.readbyqxmd.com/read/28048928/we-fg-206-02-brief-variations-of-bold-signal-in-resting-state-fmri-leading-to-functional-connectivity-pattern-identification
#18
N Ball, N Chen
PURPOSE: To assess the role of spontaneous brain activity in identifying functional connectivity patterns in the brain during resting-state using both high and low blood-oxygen level dependent (BOLD) signals from functional magnetic resonance imaging (fMRI). METHODS: fMRI BOLD signals within seed regions from known functional connectivity networks were extracted to find an average seed-region time profile. A threshold was applied to the BOLD signal and and time points were selected where the BOLD signal satisfied the threshold requirements...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048423/we-fg-bra-08-potential-role-of-the-glycolytic-oscillator-in-acute-hypoxia-in-tumors
#19
L Che Fru, E Adamson, D Campos, S Fain, S Jacques, A van der Kogel, K Nickel, C Song, R Kimple, M Kissick
PURPOSE: Oscillatory dynamics in acute hypoxia have been observed, but poorly understood. They have mostly been attributed to vascular perturbations, but no link has yet been made to metabolic causes. We set out to determine the fundamental frequencies and test for coherence in tumor oxygen dynamics and spatial properties. METHODS: Severe combined immunodeficient (SCID) mice were inoculated onto bilateral flanks with human derived head and neck carcinoma (UW-SCC22) cell line xenografts...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28046902/su-d-207a-03-potential-role-of-bold-mri-in-discrimination-of-aggressive-tumor-habitat-in-prostate-cancer
#20
J Ford, C Lopez, Y Tschudi, A Breto, K Padgett, A Pollack, R Stoyanova
PURPOSE: To determine whether blood oxygenation level dependent (BOLD) MRI signal measured in prostate cancer patients, in addition to quantitative diffusion and perfusion parameters from multiparametric (mp)MRI exams, can help discriminate aggressive and/or radioresistant lesions. METHODS: Several ongoing clinical trials in our institution require mpMRI exam to determine eligibility (presence of identifiable tumor lesion on mpMRI) and prostate volumes for dose escalation...
June 2016: Medical Physics
keyword
keyword
87384
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"