A5103229239- Advanced MRI Techniques and Applications
- Advanced Neuroimaging Techniques and Applications
- Cerebrovascular and Carotid Artery Diseases
- Acute Ischemic Stroke Management
- Optical Network Technologies
- Semiconductor Lasers and Optical Devices
- Advanced Fiber Laser Technologies
- Functional Brain Connectivity Studies
- MRI in cancer diagnosis
- Thermal Regulation in Medicine
- Medical Imaging Techniques and Applications
- Traumatic Brain Injury and Neurovascular Disturbances
- NMR spectroscopy and applications
- Cardiac Imaging and Diagnostics
- Cardiovascular Health and Disease Prevention
- Photonic and Optical Devices
- Atomic and Subatomic Physics Research
- Optical Imaging and Spectroscopy Techniques
- Advanced Photonic Communication Systems
- Liver Disease Diagnosis and Treatment
- Cardiovascular Function and Risk Factors
- Neurological Disease Mechanisms and Treatments
- Infrared Thermography in Medicine
- Bipolar Disorder and Treatment
- Coronary Interventions and Diagnostics
Case Western Reserve University
2024
University of Edinburgh
2014-2023
UK Dementia Research Institute
2017-2023
The Queen's Medical Research Institute
2022
Edinburgh Royal Infirmary
1984-2021
University of Glasgow
2012-2020
Beijing Tian Tan Hospital
2020
Capital Medical University
2020
Wentworth Institute of Technology
2019
Wellcome Centre for Integrative Neuroimaging
2009-2019
Around 50% of patients with the sleep apnea/hypopnea syndrome (SAHS) are not obese: body mass index (BMI) < 30 kg/m2. We hypothesized that local fat deposition around upper airway may be different in nonobese SAHS from normal subjects same mass. therefore examined relationship between indices general obesity; BMI, neck circumference (NC), and percentage total measured by magnetic resonance imaging three matched subject groups. Nine nonobese, nonsnoring control (BMI, 25 SE 0.7 kg/m2; NC, 38.1...
Most patients with sleep apnoea/hypopnoea syndrome (SAHS) are middle-aged men. As there conflicting data on the effects of age and gender upper airway calibre, we tested hypothesis that increasing male sex predispose to narrowing in normal subjects. We measured calibre using acoustic reflection 60 men 54 women (median 35, range 16-74 yrs) both seated supine. All dimensions, except oropharyngeal junction (OPJ), decreased (r > -0.24, p < or = 0.05) while supine (r2 0.06). Men had greater...
<h3>BACKGROUND</h3> Obesity and increased neck circumference are risk factors for the obstructive sleep apnoea/hypopnoea syndrome (SAHS). SAHS is more common in men than women, despite fact that women have higher rates of obesity greater overall body fat. One factor this apparently paradoxical sex distribution may be differing patterns fat deposition adjacent to upper airway women. A study was therefore undertaken compare normal <h3>METHODS</h3> Using T1 weighted magnetic resonance imaging,...
<h3>Objective</h3> To investigate cerebrovascular reactivity (CVR), blood flow, vascular and CSF pulsatility, their independent relationship with cerebral small vessel disease (SVD) features in patients minor ischemic stroke MRI evidence of SVD. <h3>Methods</h3> We recruited assessed CVR using oxygen level–dependent during a hypercapnic challenge, flow (CBF), pulsatility phase-contrast MRI, structural magnetic resonance brain imaging to quantify white matter hyperintensities (WMHs)...
Cerebral small vessel disease (SVD) contributes to 25% of ischemic strokes and 45% dementias. We aimed investigate the role cerebral blood flow (CBF) intracranial pulsatility in SVD. scanned 60 patients with minor stroke, representing a range white matter hyperintensities (WMH). rated WMH perivascular spaces (PVS) using semi-quantitative scales measured volume. main vessels cerebrospinal fluid (CSF) phase-contrast MRI. investigated association between flow, SVD features. In 56/60 (40 male,...
Abstract Patients undergo interventions to achieve a ‘normal’ brain temperature; parameter that remains undefined for humans. The profound sensitivity of neuronal function temperature implies the should be isothermal, but observations from patients and non-human primates suggest significant spatiotemporal variation. We aimed determine clinical relevance in by establishing how much it varies healthy adults. retrospectively screened data all recruited Collaborative European NeuroTrauma...
Abstract Purpose To study pulsatile fluid flow in a physiologically realistic model of the human carotid bifurcation, and to derive wall shear stress (WSS) vectors. Materials Methods WSS vectors were calculated from time‐resolved 3D phase‐contrast (PC) MRI measurements velocity field. The technique was first validated with sinusoidal straight tube, then used healthy bifurcation. Velocity inflow outflow regions also as boundary conditions for computational dynamics (CFD) calculations WSS,...
The subtype of α 1 ‐adrenoceptor mediating contractions human prostate to noradrenaline was characterized by use a range competitive and non‐competitive antagonists. Contractions the either (pD 2 5.5), phenylephrine 5.1) or methoxamine 4.4) were unaltered presence neuronal extraneuronal uptake blockers. Noradrenaline about 3 10 times more potent than respectively. Phenylephrine partial agonists. Pretreatment with alkylating agent, chlorethylclonidine (10 −4 m ) shifted...
Abstract Quantification of NMR visible metabolites by spectral modeling usually assumes a Lorentzian or Gaussian lineshape, despite the fact that experimental lineshapes are neither. To minimize systematic fitting errors, mixed Lorentzian‐Gaussian (Voigt) lineshape model was developed. When tested with synthetic FIDs, Voigt gave more accurate results (maximum error 2%) than either 20%) models 12%). The three substantially different peak areas in an vitro experiment, having much lower X 2...
Although much tissue damage may occur within the first few hours of ischemic stroke, duration injury is not well defined. We assessed temporal pattern neuronal loss and ischemia after stroke using magnetic resonance spectroscopic imaging (MRSI) diffusion-weighted (DWI).We measured N-acetylaspartate (NAA) lactate in 51 patients with acute at five time points, from admission to 3 months, voxels classified as normal, possibly or definitely abnormal (ischemic) according appearance lesion on DWI....
Aims Normal neurovascular coupling, mediated by the fine interplay and communication of cells within unit, is critical for maintaining normal brain activity cognitive function. This study investigated whether, with advancing age there disruption coupling specific cellular components whether effects increasing amyloid (a key feature Alzheimer's disease) would exacerbate these changes. Methods Wild‐type mice, in which deposition absent, were compared to transgenic precursor protein ( APP )...
Large vessel disease and carotid stenosis are key mechanisms contributing to vascular cognitive impairment (VCI) dementia. Our previous work, that of others, using rodent models, demonstrated bilateral common (BCAS) leads via gradual deterioration the neuro-glial-vascular unit accumulation amyloid-β (Aβ) protein. Since brain-wide drainage pathways (glymphatic) for waste clearance, including Aβ removal, have been implicated in pathophysiology VCI glial mechanisms, we hypothesized glymphatic...
Hyperammonemia is a universal finding after gastrointestinal hemorrhage in cirrhosis. We administered an oral amino acid solution mimicking the hemoglobin molecule to examine neuropsychological changes, brain glutamine levels, and magnetization transfer ratio (MTR). Forty-eight metabolically stable patients with cirrhosis no evidence of "overt" hepatic encephalopathy (HE) were randomized receive 75 g or placebo; measurements performed before 4 hours administration. Neuropsychological tests...
Abstract Objective Pyrexia is associated with poor outcome after stroke, but the temperature changes in brain stroke are poorly understood. We used magnetic resonance spectroscopic imaging (water‐to‐ N ‐acetylaspartate frequency shift) to measure cerebral noninvasively patients. Methods performed diffusion, perfusion (diffusion‐ and perfusion‐weighted imaging), imaging, compared temperatures tissues as defined by diffusion‐weighted appearance (definitely abnormal, possibly abnormal...
In nine healthy subjects, magnetic resonance imaging was used to measure blood flow waveforms in the common (CCA), internal (ICA) and external (ECA) carotid arteries. Useful data were acquired from 14 arteries total. Flow rates determined regions of interest placed over CINE-phase contrast velocity encoded images. Use a normalized cardiac cycle allowed combination individuals. Time-averaged group mean 6.16, 4.14 1.59 ml s−1 for CCA, ICA ECA, respectively. values division ratios ICA/CCA,...