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Arterial Remodeling (arterial + remodeling)
Selected AbstractsIn Vivo Optical Analysis of Quantitative Changes in Collagen and Elastin During Arterial Remodeling,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 2 2005Alexander Christov ABSTRACT Altered collagen and elastin content correlates closely with remodeling of the arterial wall after injury. Optical analytical approaches have been shown to detect qualitative changes in plaque composition, but the capacity for detection of quantitative changes in arterial collagen and elastin content in vivo is not known. We have assessed fluorescence spectroscopy for detection of quantitative changes in arterial composition in situ, in rabbit models of angioplasty and stent implant. Fluorescence emission intensity (FEI) recorded at sites remote from the primary implant site was correlated with immunohistochemical (IH) analysis and extracted elastin and collagen. FEI was significantly decreased (P < 0.05) after treatment with anti-inflammatory agents, and plaque area decreased on comparison with saline-treated rabbits after stent implant or angioplasty (P, 0.013). Excellent correlations for FEI with elastin and collagen I, III and IV content measured by IH (R2, 0.961) analysis were detected by multiple regression (MR) analysis. Good correlations also were found for FEI with elastin and collagen measured by high-performance liquid chromatography; MR analysis provided highly predictive values for collagen and elastin (R2, 0.994). Fluorescence spectroscopic analysis detects quantitative compositional changes in arterial connective tissue in vivo, demonstrating changes at sites remote from primary angioplasty and stent implant sites. [source] MRI of early- and late-stage arterial remodeling in a low-level cholesterol-fed rabbit model of atherosclerosisJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 4 2007John A. Ronald MS Abstract Purpose To monitor early- and late-stage arterial remodeling following low-level cholesterol (CH) feeding in rabbits using a standardized MRI protocol. Materials and Methods New Zealand White rabbits were fed a CH diet (0.25% w/w) (n = 15) or normal chow (n = 6) and imaged either at 0, 2, 6, 8, and 11 months ("early-stage") or 12, 14, 16, 18, and 20 months ("late-stage"). T2-weighted fast-spin-echo images (,200 ,m in-plane resolution) of aortic lesions were collected using either a 1.5 or 3.0T MR scanner interfaced with a customized surface RF coil. Luminal (LA), outer vessel wall boundary (OVBA), and vessel wall areas (VWA) were assessed. Results Among CH-fed animals in the early-stage group, increased VWA associated with decreased OVBA and a more pronounced decrease in LA was first detectable at 8 months. These changes became more evident between 8 and 11 months. In the late-stage group, lesions continued to grow in response to CH-feeding, as VWA significantly increased at regular 2-month intervals. Beyond 16 months, signal intensity differences (reflecting increased lesion complexity) within the vessel wall were noted. Conclusion This often-overlooked rabbit model combined with customized MR technology holds tremendous promise for studying the natural progression, regression, and remodeling of atherosclerotic lesions. J. Magn. Reson. Imaging 2007;26:1010,1019. © 2007 Wiley-Liss, Inc. [source] Progenitor cell trafficking in the vascular wallJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 2009M. HRISTOV Summary., Adult endothelial as well as smooth muscle progenitor cells are engaged in the complex pathophysiology of atherosclerosis including primary remodeling with development and progression of atherosclerotic plaques as well as secondary complications associated with ischemia, endothelial damage, neointimal growth and transplant arteriosclerosis. These adult vascular precursor cells correspond to similar embryonic stem cell-derived progeny and are primarily located in bone marrow and peripheral blood. Recently, specific investigation on their recruitment emerged as a novel fundamental in the pathogenesis of arterial remodeling, plaque stability and angiogenesis. This multifaceted process of mobilization and homing is regulated by numerous chemokines, adhesion molecules and growth factors that guide and control the trafficking of vascular progenitor cells to the arterial wall after injury or during ischemia. [source] Reproducibility of coronary lumen, plaque, and vessel wall reconstruction and of endothelial shear stress measurements in vivo in humansCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 1 2003Ahmet U. Coskun PhD Abstract The purpose of this study was to assess the reproducibility of an in vivo methodology to reconstruct the lumen, plaque, and external elastic membrane (EEM) of coronary arteries and estimate endothelial shear stress (ESS). Ten coronary arteries without significant stenoses (five native and five stented arteries) were investigated. The 3D lumen and EEM boundaries of each coronary artery were determined by fusing end-diastolic intravascular ultrasound images with biplane coronary angiograms. Coronary flow was measured. Computational fluid dynamics was used to calculate local ESS. Complete data acquisition was then repeated. Analysis was performed on each data set in a blinded manner. The intertest correlation coefficients for all arteries for the two measurements of lumen radius, EEM radius, plaque thickness, and ESS were r = 0.96, 0.96, 0.94, 0.91, respectively (all P values < 0.0001). The 3D anatomy and ESS of human coronary arteries can be reproducibly estimated in vivo. This methodology provides a tool to examine the effect of ESS on atherogenesis, remodeling, and restenosis; the contribution of arterial remodeling and plaque growth to changes in the lumen; and the impact of new therapies. Catheter Cardiovasc Interv 2003;60:67,78. © 2003 Wiley,Liss, Inc. [source] | ||||||||||