Early detection of vascular inflammation would allow deployment of targeted strategies for the prevention or treatment of multiple disease states. Because vascular inflammation is not detectable with commonly used imaging modalities, we hypothesized that phenotypic changes in perivascular adipose tissue (PVAT) induced by vascular inflammation could be quantified using a new computerized tomography (CT) angiography methodology. We show that inflamed human vessels release cytokines that prevent lipid accumulation in PVAT-derived preadipocytes in vitro, ex vivo, and in vivo. We developed a three-dimensional PVAT analysis method and studied CT images of human adipose tissue explants from 453 patients undergoing cardiac surgery, relating the ex vivo images with in vivo CT scan information on the biology of the explants. We developed an imaging metric, the CT fat attenuation index (FAI), that describes adipocyte lipid content and size. The FAI has excellent sensitivity and specificity for detecting tissue inflammation as assessed by tissue uptake of 18F-fluorodeoxyglucose in positron emission tomography. In a validation cohort of 273 subjects, the FAI gradient around human coronary arteries identified early subclinical coronary artery disease in vivo, as well as detected dynamic changes of PVAT in response to variations of vascular inflammation, and inflamed, vulnerable atherosclerotic plaques during acute coronary syndromes. Our study revealed that human vessels exert paracrine effects on the surrounding PVAT, affecting local intracellular lipid accumulation in preadipocytes, which can be monitored using a CT imaging approach. This methodology can be implemented in clinical practice to noninvasively detect plaque instability in the human coronary vasculature.
Objective To determine if there is a relation between aspirin "resistance" and clinical outcomes in patients with cardiovascular disease. Design Systematic review and meta-analysis. Data source Electronic literature search without language restrictions of four databases and hand search of bibliographies for other relevant articles. Review methods Inclusion criteria included a test for platelet responsiveness and clinical outcomes. Aspirin resistance was assessed, using a variety of platelet function assays.
Oxidative stress plays a critical role in the vascular complications of type 2 diabetes. We examined the effect of type 2 diabetes on NADPH oxidase in human vessels and explored the mechanisms of this interaction. Segments of internal mammary arteries (IMAs) with their perivascular adipose tissue (PVAT) and thoracic adipose tissue were obtained from 386 patients undergoing coronary bypass surgery (127 with type 2 diabetes). Type 2 diabetes was strongly correlated with hypoadiponectinemia and increased vascular NADPH oxidase-derived superoxide anions (O 2 _ 2 ). The genetic variability of the ADIPOQ gene and circulating adiponectin (but not interleukin-6) were independent predictors of NADPH oxidasederived O 2 _ 2 . However, adiponectin expression in PVAT was positively correlated with vascular NADPH oxidasederived O 2 _ 2 . Recombinant adiponectin directly inhibited NADPH oxidase in human arteries ex vivo by preventing the activation/membrane translocation of Rac1 and downregulating p22 phox through a phosphoinositide 3-kinase/Akt-mediated mechanism. In ex vivo coincubation models of IMA/PVAT, the activation of arterial NADPH oxidase triggered a peroxisome proliferator-activated receptor-g-mediated upregulation of the adiponectin gene in the neighboring PVAT via the release of vascular oxidation products. We demonstrate for the first time in humans that reduced adiponectin levels in individuals with type 2 diabetes stimulates vascular NADPH oxidase, while PVAT "senses" the increased NADPH oxidase activity in the underlying vessel and responds by upregulating adiponectin gene expression. This PVAT-vessel interaction is identified as a novel therapeutic target for the prevention of vascular complications of type 2 diabetes.
The Nuss procedure has already been shown to have a positive impact on both the physical and psychosocial well-being of children who are suffering from pectus excavatum deformity. We have shown a similar positive impact in young male adults, in the short term.
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