Search results for " Vessel"

Immunoglobulin E (IgE) and ischemic heart disease. Which came first, the chicken or the egg?

2014

Several lines of evidence demonstrate that the immune system plays a pivotal role in development and progression of ischemic heart disease (IHD). More recently, a series of biological and clinical investigations has generated new interest about the existence of a relationship between a specific class of immunoglobulin, that is immunoglobulin E (IgE), and IHD. Data obtained in several epidemiological studies have convincingly demonstrated that the concentration of total serum IgEs is significantly increased in patients with IHD and often correlates with the prognosis. The putative mechanisms are essentially mediated by a physiological interaction between IgEs and mast cells, which triggers t…

Modelling the effect of porosity on the mechanical properties of unidirectional composites. The case of thick-walled pressure vessels

2018

International audience; The present article highlights morphological features present in composite pressure vessels. The use of X-ray microtomography provides three-dimensional information about the voids in a large thick-walled type 3 pressure vessel at the mesoscopic scale. The observations show that the porosity structure depends strongly on composite thickness and orientation. A numerical approach is proposed to model realistically the damage phenomena in pressure vessels.

Angiogenesis control in spine regeneration

2012

Abstract: The intervertebral disc (IVD) has a complex vascularisation pattern. While the nucleus pulposus is avascular, the annulus fibrosus as well as the endplates are vascularised. IVD degeneration is often accompanied, on the one hand, by blood vessel ingrowth into the nucleus pulposus and, on the other hand, by diminished vascularisation of the endplates. Tissue engineering of IVD, therefore, has to address the differences in the vascularisation of IVD compartments. This chapter summarises current knowledge about the mechanisms of angiogenesis and its physiological and pathological role in IVD biology. Different strategies to control angiogenesis are discussed in the chapter with examp…

Drug-Coated Balloon vs. Stent for de novo Non-small Coronary Artery Disease: A Systematic Review and Meta-Analysis

2021

Introduction: Drug-coated balloon (DCB) has been an attractive option in de novo vessels. A systematic review and meta-analysis were conducted to evaluate the efficacy and safety of DCB vs. stent for treating de novo lesions in non-small vessels.Methods: Studies in PubMed, Embase, the Cochrane Central Register of Controlled Trials, and Web of Science were searched (from their commencement to March 2021). This meta-analysis was performed by Review Manager 5.3.Results: A total of 3 random controlled trials (RCTs) with 255 patients and 2 observational studies (OS) with 265 patients were included in this meta-analysis following our inclusion criteria. It could be observed that DCB presented no …

Appropriateness of surgery performed for abdominal aortic aneurysm at tertiary hospitals in Spain

2021

Background: The aim of this study was to analyze the appropriateness of the type of repair (open or endovascular) performed for abdominal aortic aneurysm (AAA) in five university hospitals in Spain, according to evidence-based recommendations. Methods: A multicenter, retrospective cross-sectional study of patients with AAA who underwent elective open surgical repair (OSR) or endovascular aneurysm repair (EVAR). Data were collected on demographic and clinical variables and type of surgical repair. A pair of vascular surgeons from each participating hospital performed a blinded assessment based on GRADE recommendations. The concordance between the two evaluators and the agreement between thei…

Proof testing and lifetime reliability of carbon fibre reinforced composite pressure vessels

2013

International audience

A methodology for the control of the residual lifetimes of carbon fibre reinforced composite pressure vessels

2005

International audience; Pressure vessels must be periodically proof tested. Traditional techniques for metal vessels are inapplicable for composite vessels as the latter do not break by crack propagation so that the reasoning behind the traditional testing procedures is not appropriate. Damage accumulation leading to the degradation of a composite vessel is by fibre failure. Fibres show a wide distribution in strengths and loading a composite inevitably breaks some. The method which has been developed is supported by an analysis of delayed fibre failure due to the relaxation of the resin around fibre breaks. This provokes overloading of intact fibres neighbouring breaks. The time until a cr…

Effect of mesoangioblast extracellular vesicle on cell migration and vessel formation of human endothelial cell

2015

CFD simulation of a mixing-sensitive reaction in unbaffled vessels

2008

Stirred tanks are widely used in the process industry, often to carry out complex chemical reactions. In many of such cases the perfect mixing hypothesis is not applicable for modelling purposes, and more detailed modelling approaches are required in order to accurately describe the reactor behaviour. In this work a fully predictive modelling approach, based on Computational Fluid Dynamics, is developed. Model predictions are compared with original experimental data obtained in un unbaffled stirred vessel with a parallel-competitive, mixing sensitive reaction scheme. Notably, satisfactory results are obtained at all injection rates with no recourse to micro-mixing model, thus confirming the…

Association between resting blood pressure and maximal blood pressure response to exercise and arterial health

2022

We investigated the longitudinal associations of blood pressure, cardiorespiratory fitness, and arterial stiffness among children. Arterial stiffening has been repeatedly shown to be a cardiovascular mortality predictor and can be observed early in childhood. As such, it is crucial to understand whether a child’s blood pressure, fitness level, and body composition can predict early signs of atherosclerosis and arterial stiffening. The current study examined the relationship between blood pressure, cardiorespiratory fitness, and arterial stiffness over time in children, using data from the Physical and Nutrition in Children (PANIC) Study. It is a physical and dietary intervention study condu…