Characteristics of carotid atherosclerotic plaques of chronic lipid apheresis patients as assessed by In Vivo High-Resolution CMR - a comparative analysis

Grimm, Nikolaou Konstantin, Schindler Andreas, Hettich Reinhard, Heigl Franz, Cyran, Schwarz Florian, Klingel Reinhard, Karpinska Anna, Yuan Chun, Dichgans Martin, Reiser, Saam Tobias

Description

Components of carotid atherosclerotic plaques can reliably be identified and quantified using high resolution in vivo 3-Tesla CMR. It is suspected that lipid apheresis therapy in addition to lowering serum lipid levels also has an influence on development and progression of atherosclerotic plaques. The purpose of this study was to evaluate the influence of chronic lipid apheresis (LA) on the composition of atherosclerotic carotid plaques. Methods 32 arteries of 16 patients during chronic LA-therapy with carotid plaques and stenosis of 1–80% were matched according to degree of stenosis with 32 patients, who had recently suffered an ischemic stroke. Of these patients only the asymptomatic carotid artery was analyzed. All patients underwent black-blood 3 T CMR of the carotids using parallel imaging and dedicated surface coils. Cardiovascular risk factors were recorded. Morphology and composition of carotid plaques were evaluated. For statistical evaluation Fisher’s Exact and unpaired t -test were used. A p-value <0.05 was considered statistically significant. Results Patients in the LA-group were younger (63.5 vs. 73.9. years, p<0.05), had a higher prevalence of hypercholesterolemia and of established coronary heart disease in patients and in first-degree relatives (p<0.05, respectively). LA-patients had smaller maximum wall areas (49.7 vs. 59.6mm 2 , p<0.05), showed lower prevalence of lipid cores (28.1% vs. 56.3%, p<0.05) and the lipid content was smaller than in the control group (5.0 vs. 11.6%, p<0.05). Minimum lumen areas and maximum total vessel areas did not differ significantly between both groups. Conclusion Results of this study suggest that, despite a severer risk profile for cardiovascular complications in LA-patients, chronic LA is associated with significantly lower lipid content in carotid plaques compared to plaques of patients without LA with similar degrees of stenosis, which is characteristic of clinically stable plaques.

Sujets

• Atherosclerosis
• Stroke
• Cardiovascular disease

Informations

• Publié par: biomed
• Publié le: 01 janvier 2012
• Nombre de lectures: 9
• Langue: English
• Poids de l'ouvrage: 1 Mo

Extrait

Graham and RichardsonEvoDevo2012,3:24 http://www.evodevojournal.com/content/3/1/24

R E V I E WOpen Access Developmental and evolutionary origins of the pharyngeal apparatus * Anthony Grahamand Jo Richardson

Abstract The vertebrate pharyngeal apparatus, serving the dual functions of feeding and respiration, has its embryonic origin in a series of bulges found on the lateral surface of the head, the pharyngeal arches. Developmental studies have been able to discern how these structures are constructed and this has opened the way for an analysis of how the pharyngeal apparatus was assembled and modified during evolution. For many years, the role of the neural crest in organizing pharyngeal development was emphasized and, as this was believed to be a uniquely vertebrate cell type, it was suggested that the development of the pharyngeal apparatus of vertebrates was distinct from that of other chordates. However, it has now been established that a key event in vertebrate pharyngeal development is the outpocketing of the endoderm to form the pharyngeal pouches. Significantly, outpocketing of the pharyngeal endoderm is a basal deuterostome character and the regulatory network that mediates this process is conserved. Thus, the framework around which the vertebrate pharyngeal apparatus is built is ancient. The pharyngeal arches of vertebrates are, however, more complex and this can be ascribed to these structures being populated by neural crest cells, which form the skeletal support of the pharynx, and mesoderm, which will give rise to the musculature and the arch arteries. Within the vertebrates, as development progresses beyond the phylotypic stage, the pharyngeal apparatus has also been extensively remodelled and this has seemingly involved radical alterations to the developmental programme. Recent studies, however, have shown that these alterations were not as dramatic as previously believed. Thus, while the evolution of amniotes was believed to have involved the loss of gills and their covering, the operculum, it is now apparent that neither of these structures was completely lost. Rather, the gills were transformed into the parathyroid glands and the operculum still exists as an embryonic entity and is still required for the internalization of the posterior pharyngeal arches. Thus, the key steps in our phylogenetic history are laid out during the development of our pharyngeal apparatus. Keywords:Deuterostomes, Endoderm, Operculum, Parathyroid, Pharyngeal arches, Pharyngeal pouches, Vertebrate evolution

Review While ontogeny does not simply recapitulate phylogeny, it is undoubtedly true that ontogeny is shaped by phyl ogeny. Developmental processes have evolutionary his tories and these can be uncovered through experimental analysis and comparative studies across a range of spe cies. It is through these approaches that insights into how developmental processes have been assembled over evolution can be garnered. In this article, we wish to discuss the development of the pharynx and to make the case that this process has been profoundly shaped by

* Correspondence: [e-mail] MRC Centre for Developmental Neurobiology, King’s College London, London SE1 1UL, UK

its evolutionary history. Importantly, we are now at a point where the developmental and evolutionary studies can be brought together and we can identify steps that have emerged successively during evolution. We can un cover deeply conserved features of pharyngeal develop ment that preceded the emergence of the vertebrates and indeed can now be seen to have evolved as early as the deuterostomes. We can also relate the remodelling of the pharyngeal region that occurs during development to evolutionary modifications that occurred with in the vertebrates. We would argue that in the pharynx developmental events collectively betray our phylogen etic history.

© 2012 Graham and Richardson; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.