Search results for "dilation"

Stimulation of endothelial nitric oxide synthase by proinsulin C-peptide.

2003

There is increasing evidence for biological functions of human C-peptide. Recently, we have described that proinsulin C-peptide increases nutritive capillary blood flow and restores erythrocyte deformability in type 1 diabetic patients, whereas it has no such effect in non-diabetic subjects. The aim of the current study was to elucidate cellular mechanisms of this vasodilator effect in vitro by measuring the nitric oxide (NO)-mediated increase of cGMP production in a RFL-6 reporter cell assay and by demonstrating endothelial calcium influx with the Fluo-3 technique. C-peptide increased the release of NO from endothelial NO synthase (eNOS) in bovine aortic endothelial cells in a concentratio…

Diameter Control in the Arteriolar Tree by Changes in Post-Capillary Resistance

1997

Presently, the mechanisms underlying local adjustment of organ perfusion to the metabolic needs of the tissue are not well understood. Even though a large number of vasoactive substances is known to be released upon variations in tissue metabolism,24,28 the exact mechanisms of their action are unclear: Because diffusion is a slow and inefficient transport process for covering long distances, arterioles can only sense those changes in concentration and hence in release rate of these mediators with acceptable spatial and temporal resolution that originate from their immediate vicinity. On the other hand, perfusion needs to be regulated such that also the worst supplied tissue regions located …

Carbon monoxide: mechanisms of action and potential clinical implications.

2013

International audience; Small amounts of carbon monoxide (CO) are continuously produced in mammals. The intracellular levels of CO can increase under stressful conditions following the induction of HO-1 (heme oxygnase-1), a ubiquitous enzyme responsible for the catabolism of heme. Unlike nitric oxide, which is a free radical, CO does not contain free electrons but may be involved in oxidative stress. The carbonate radical has been proposed to be a key mediator of oxidative damage resulting from peroxynitrite production, likewise, the precursor of the carbonate radical anion being bicarbonate and carbon dioxide. We report herein some of the transcription factors and protein kinases involved …

The interaction between circadian rhythms of endothelial function: resting versus recruitable endothelial function

2013

Endothelial dysfunction and carotid lesions are strong predictors of clinical events in patients with early stages of atherosclerosis: a 24-month fol…

2008

Background The purpose of this study was to investigate whether the vasodilator response to brachial artery and the presence of carotid lesions may have a prognostic significance in patients with early stages of atherosclerosis. Methods and results Vascular echography was performed to analyze flow-mediated vasodilatation (FMD) at the brachial artery and intima–media thickness (IMT) of carotid arteries in 84 asymptomatic patients. At baseline, we evaluated all the established traditional cardiovascular risk factors. Transient ischemic attack, stroke, effort or unstable angina, acute myocardial infarction, peripheral arterial disease and cerebrovascular and cardiovascular death served as outc…

Endothelial Nitric Oxide Synthase

2007

Endothelial nitric oxide synthase (eNOS; also referred to as NOS3 or NOSIII), a low output enzyme is the prototypical isoform being found in endothelial cells. This isoform (like nNOS) synthesizes NO in a short-lasting, pulsatile, Ca++/calmodulin-activated manner. Endothelium-derived NO is a physiologically significant vasodilator and inhibitor of platelet aggregation and adhesion. In addition, vascular NO can prevent leukocyte adhesion to the endothelium by down-regulating the leukocyte adhesion glycoprotein complex CD11/CD18. Finally, endothelial NO has also been shown to inhibit the proliferation of vascular smooth muscle cells. Therefore, endothelial NO is likely to represent a protecti…

The role of industry influence in sinus balloon dilation: Trends over time

2018

OBJECTIVE Balloon dilation (BD) is a controversial alternative to conventional sinus surgery. The role of industry on practice patterns remains unknown. The aim of this study was to determine whether industry payments from BD manufacturers influence practice patterns for otolaryngologists and evaluate how these payments change over time. METHODS Retrospective cohort study using Medicare Provider Utilization and Payment (PUP) Data and Center for Medicare and Medicaid Services Open Payments (OP) general payment datasets. A total of 294 otolaryngologists identified in the PUP dataset who performed BD procedures from January 1, 2013, to December 31, 2015, were cross-referenced in the OP dataset…

Mathematical Morphology for Color Images: An Image-Dependent Approach

2012

This paper proposes one possibility to generalize the morphological operations (particularly, dilation, erosion, opening, and closing) to color images. First, properties of a desirable generalization are stated and a brief review is done on former approaches. Then, the method is explained, which is based on a total ordering of the colors in an image induced by its color histogram; this is valid for just one image and may present problems in smoothly coloured images. To solve these drawbacks a refinement consisting of smoothing the histogram and using a joint histogram of several images is presented. Results of applying the so-defined morphological operations on several sets of images are sh…

Comparative Analysis of the Vascular Actions of Diterpenes Isolated from Euphorbia canariensis

1998

Abstract We have analysed the effects of 2,3-diepiingol 7,12-diacetate-8-isobutyrate (compound 1), ingenol-3-angelate-17-benzoate (compound 2), ingenol-3-angelate-17-benzoate-20-acetate (compound 3) and 3,5,7,8,9,15-hexahydroxyjatropha-6(17),11-dien-14-one-5,8-bis(2-methylbutyrate)-7-(2-methylpropionate) (compound 4), four diterpenes isolated from E. canariensis, on the isometric tension developed by isolated rabbit basilar and carotid arteries. Concentration-response curves to these compounds were obtained cumulatively in both arteries at resting tension and active tone (KCl, 50 mM). At resting tension a concentration-dependent contraction was induced by the four compounds. In the basilar …

W1113 Efficacy and Safety of Endoscopic Balloon Dilation of Symptomatic Intestinal Crohn's Disease Strictures

2009

Aim: To evaluate prospectively the clinical efficacy and safety of endoscopic hydrostatic balloon dilation in a consecutive cohort of symptomatic intestinal Crohn’s disease strictures. Methods: Between September 2003 and December 2008 we performed endoscopic balloon dilations in 37 Crohn’s disease patients with 39 intestinal symptomatic strictures (4 naive and 35 postoperative). Dilations were performed using a Rigiflex through-the-scope balloon. Clinical success rate was claimed if a patient remained asymptomatic and did not require surgery or further endoscopic dilation, following technical success. Actuarial curves of clinical, endoscopic (redilation) and surgical recurrence were obtaine…