212 research outputs found
Signal characteristic alterations of carotid artery dissection on high resolution magnetic resonance imaging: a follow-up study
MRI measurements of carotid plaque in the atherosclerosis risk in communities (ARIC) study: Methods, reliability and descriptive statistics
To measure carotid plaque components using MRI and estimate reliability in the population-based Atherosclerosis Risk in Communities (ARIC) study
Segment-specific associations between local haemodynamic and imaging markers of early atherosclerosis at the carotid artery: an in vivo human study
Low and oscillatory wall shear stress (WSS) has long been hypothesized as a risk factor for atherosclerosis; however, evidence has been inferred primarily from model and post-mortem studies, or clinical studies of patients with already-developed plaques. This study aimed to identify associations between local haemodynamic and imaging markers of early atherosclerosis. Comprehensive magnetic resonance imaging allowed quantification of contrast enhancement (CE) (a marker of endothelial dysfunction) and vessel wall thickness at two distinct segments: the internal carotid artery bulb and the common carotid artery (CCA). Strict criteria were applied to a large dataset to exclude inward remodelling, resulting in 41 cases for which personalized computational fluid dynamic simulations were performed. After controlling for cardiovascular risk factors, bulb wall thickening was found to be weakly, but not significantly, associated with oscillatory WSS. CE at the bulb was significantly associated with low WSS (p < 0.001) and low flow helicity (p < 0.05). No significant associations were found for the CCA segment. Local haemodynamics at the bulb were significantly correlated with blood flow rates and heart rates, but not carotid bifurcation geometry (flare and curvature). Therefore low, but not oscillatory, WSS is an early independent marker of atherosclerotic changes preceding intimal thickening at the carotid bulb
SELP and SELPLG Genetic Variation Is Associated with Cell Surface Measures of SELP and SELPLG: The Atherosclerosis Risk in Communities Carotid MRI Study
P-selectin (SELP) and its ligand, P-selectin glycoprotein ligand 1 (SELPLG), play key roles in both the inflammatory response and the atherosclerotic process. Previous studies have shown genetic variation in the SELP gene [selectin P (granule membrane protein 140kDa, antigen CD62)] to be associated with plasma SELP concentrations; however, the major biological function of SELP (and SELPLG) is at the cell surface. We therefore investigated the association of SELP polymorphisms with platelet SELP measures and polymorphisms in the SELPLG gene (selectin P ligand) with lymphocyte, granulocyte, and monocyte SELPLG measures among 1870 participants in the Atherosclerosis Risk in Communities (ARIC) Carotid MRI study
MR Imaging Measures of Intracranial Atherosclerosis in a Population-based Study
Our MR imaging protocol characterized individuals at greatest risk for having intracranial atherosclerotic disease lesions and offers a reliable technique for identifying lesions in patients with suspected disease
Statistical Inference for Valued-Edge Networks: Generalized Exponential Random Graph Models
Across the sciences, the statistical analysis of networks is central to the
production of knowledge on relational phenomena. Because of their ability to
model the structural generation of networks, exponential random graph models
are a ubiquitous means of analysis. However, they are limited by an inability
to model networks with valued edges. We solve this problem by introducing a
class of generalized exponential random graph models capable of modeling
networks whose edges are valued, thus greatly expanding the scope of networks
applied researchers can subject to statistical analysis
Biased Discrete Symmetry Breaking and Fermi Balls
The spontaneous breaking of an approximate discrete symmetry is considered,
with the resulting protodomains of true and false vacuum being separated by
domain walls. Given a strong, symmetric Yukawa coupling of the real scalar
field to a generic fermion, the domain walls accumulate a gas of fermions,
which modify the domain wall dynamics. The splitting of the degeneracy of the
ground states results in the false vacuum protodomain structures eventually
being fragmented into tiny false vacuum bags with a Fermi gas shell (Fermi
balls), that may be cosmologically stable due to the Fermi gas pressure and
wall curvature forces, acting on the domain walls. As fermions inhabiting the
domain walls do not undergo number density freeze out, stable Fermi balls exist
only if a fermion anti-fermion asymmetry occurs. Fermi balls formed with a new
Dirac fermion that possesses no standard model gauge charges provide a novel
cold dark matter candidate.Comment: 10 pages, uuencoded file containing standard LaTeX and 1 PostScript
figure, Albberta Thy-1-9
Association of the platelet GPIIb/IIIa polymorphism with atherosclerotic plaque morphology. The Atherosclerosis Risk in Communities (ARIC) Study
Platelet activation and aggregation play an important role in the pathogenesis of cardiovascular disease. We examined the association of a single nucleotide polymorphism (SNP) in the GPIIIa platelet glycoprotein (Leu33Pro) with carotid artery plaque morphology and with expression of platelet markers using data from the Atherosclerosis Risk in Communities (ARIC) Carotid MRI study
Chromosome 10Q2432 Variants associate With Brain arterial Diameters in Diverse Populations: a Genome-Wide association Study
BACKGROUND: Brain arterial diameters (BADs) are novel imaging biomarkers of cerebrovascular disease, cognitive decline, and dementia. Traditional vascular risk factors have been associated with BADs, but whether there may be genetic determinants of BADs is unknown.
METHODS AND RESULTS: The authors studied 4150 participants from 6 geographically diverse population-based cohorts (40% European, 14% African, 22% Hispanic, 24% Asian ancestries). Brain arterial diameters for 13 segments were measured and averaged to obtain a global measure of BADs as well as the posterior and anterior circulations. A genome-wide association study revealed 14 variants at one locus associated with global BAD at genome-wide significance (
CONCLUSIONS: The current study reveals 3 novel risk loci
Relation of cholesterol and lipoprotein parameters with carotid artery plaque characteristics: The Atherosclerosis Risk in Communities (ARIC) carotid MRI study
There is a paucity of data regarding relations of apolipoproteins (apolipoprotein B [ApoB] and apolipoprotein A-1 [Apo A-1]), lipoprotein particle measures (low-density lipoprotein particle concentration [LDLp] and high-density lipoprotein particle concentration [HDLp]), and lipoprotein cholesterol measures (low-density lipoprotein cholesterol [LDL-C], non–high-density lipoprotein cholesterol [non– HDL-C], and high-density lipoprotein cholesterol [HDL-C]) with atherosclerotic plaque burden, plaque eccentricity, and lipid-rich core presence as a marker of high-risk plaques
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