Search results for " vascular"
showing 10 items of 945 documents
Vascular endothelial growth factor expression in nasal polyps of aspirin-intolerant patients.
2012
Objective To study differences between aspirin-tolerant patients and aspirin-intolerant patients concerning vascular endothelial growth factor (VEGF) expression. Recent publications strongly suggest the involvement of VEGF and its receptors in the pathophysiologic process of nasal polyps. Design We subjected 43 polyp specimens to semiquantitative immunohistochemical analysis. We quantified VEGF and its receptors (Flk, Flt, and neuropilin) in all samples. To gain insight into potential VEGF-mediated cellular responses, we determined proliferative (Ki67) and apoptotic (caspase 3) indices. Patients Polyp samples were obtained from 22 aspirin-intolerant patients and from 21 aspirin-tolerant pat…
The VEGF/VEGF-R Axis in Sporadic Vestibular Schwannomas Correlates with Irradiation and Disease Recurrence
2012
<b><i>Background/Aims:</i></b> The molecular mechanisms downstream of mutated neurofibromatosis type 2 (NF2) gene resulting in the growth and development of vestibular schwannoma (VS) are controversial. Several lines of evidence suggest the involvement of the vascular endothelial growth factor (VEGF) pathway in VS development. Given that recent studies of VEGF blockade in patients with NF2-associated VS showed positive effects on VS growth control, we initiated this comprehensive study of the VEGF pathway in sporadic VS. <b><i>Methods:</i></b> A tissue microarray analysis of 182 sporadic VS was conducted. The expression of VEGF and its recepto…
Relaxin in Obstructive Sleep Apnea: Relationship with Blood Pressure and Inflammatory Mediators
2015
<b><i>Background:</i></b> Obstructive sleep apnea (OSA) is associated with nocturnal intermittent hypoxia, which may be responsible for increased circulating levels of vascular endothelial growth factor (VEGF) and inflammatory mediators, such as metalloproteinases (MMPs), and which contributes to the pathogenesis of systemic hypertension. Why some OSA patients remain normotensive is poorly understood. Relaxin-2, a pregnancy hormone, may sometimes circulate in men and could increase in hypoxic conditions. It exerts a vasodilatory activity and can modulate the release of molecules, such as MMPs and VEGF. <b><i>Objectives:</i></b> The objective o…
Vascular endothelial growth factor gene polymorphisms in Behçet's disease
2004
Objective. To evaluate potential associations of vascular endothelial growth factor (VEGF) gene polymorphisms with Behçet's disease (BD) and disease expression. Methods. Case patients were 122 consecutive Italian patients with BD followed at the Rheumatology, Ophthalmology, and Neurology Units in Bologna, Ferrara, Milano, Palermo, Potenza, Prato, Reggio Emilia, and Trento over a 3-year period (1997-99) and who satisfied the International Study Group criteria for BD. Also selected as a control group were 200 healthy age and sex matched blood donors. All patients with BD and controls were genotyped by polymerase chain reaction and allele-specific oligonucleotide techniques for +936 C/T (rs302…
Continuous therapy with transdermal nitroglycerin does not affect biomarkers of vascular inflammation and injury in healthy volunteers.
2009
Continuous exposure to nitroglycerin (GTN) results in development of tolerance and is associated with increased free radical production and abnormal endothelial function. Elevated plasma biomarkers of inflammation have been shown to be associated with endothelial dysfunction in most cardiovascular conditions. It remains unclear whether exposure to GTN is also associated with increased biomarkers of endothelial and vascular injury or vascular inflammation. In an investigator-blind study, a total of 28 healthy volunteers were randomized to continuous therapy with GTN (0.6 mg/h 24 h/day for 7 days) or no therapy. Venous blood was collected on day 0 and day 7. Plasma levels of markers such as …
Pentaerythrityl Tetranitrate and Nitroglycerin, but not Isosorbide Mononitrate, Prevent Endothelial Dysfunction Induced by Ischemia and Reperfusion
2007
Background— Short term exposure to nitroglycerin (GTN) has protective properties that are similar to ischemic preconditioning. Whether other organic nitrates such as pentaerithrityl tetranitrate (PETN) and isosorbide mononitrate (ISMN) have similar protective effects has not been explored. Methods and Results— In a randomized, parallel, double blind, controlled trial, 37 healthy young volunteers received no therapy (n=10), transdermal GTN 1.2 mg for 2 hours (n=9), PETN 80 mg (n=9), or ISMN 40 mg (n=9). Twenty-four hours later, endothelium-dependent flow-mediated vasodilation (FMD) was measured before and after local exposure to ischemia and reperfusion (IR). In the no therapy group, IR blu…
Endothelium-independent contractions of human cerebral arteries in response to vasopressin.
1990
We studied the effects of vasopressin in isolated segments from branches (500-700 micrograms in external diameter) of human middle cerebral arteries obtained during autopsy of 15 patients who had died 3-8 hours before. Paired segments, one normal and the other de-endothelized by gentle rubbing, were mounted for isometric recording of tension in organ baths. In 11 normal segments, vasopressin produced concentration-dependent contractions with an EC50 of 7.0 X 10(-10) M. Removal of the endothelium from 12 segments did not significantly affect vasopressin-induced contractions. Vasopressin produced further contractions in arterial segments with (n = 4) or without (n = 5) endothelium precontract…
Effects of vasopressin on human renal arteries
1996
The effects of vasopressin were studied in isolated rings from branches (2-3 mm in external diameter) of human renal arteries obtained from 18 patients undergoing nephrectomy for non-obstructive neoplasia. In arterial rings under resting tension, vasopressin produced concentration-dependent and endothelium-independent contractions with an EC 50 of 9.1 x 10 -10 mol L -1 . The vasopressin V 1 receptor antagonist d(CH 2 ) 5 Tyr(Me)AVP (10 -6 mol L -1 ) displaced the control curve to vasopressin 564-fold to the right in a parallel manner. In precontracted arterial rings and previously treated with the V 1 antagonist (10 -6 mol L -1 ) vasopressin caused endothelium-independent relaxation. The re…
Increased plasma xanthine oxidase activity is related to nuclear factor kappa beta activation and inflammatory markers in familial combined hyperlipi…
2010
Abstract Background and aims Xanthine oxidase (XO) has been described as one of the major enzymes producing free radicals in blood. Oxidative stress and inflammatory processes have been implicated in the pathogenesis of endothelial dysfunction and the progression of atherosclerosis but until now, there is little data about the influence of vascular prooxidant systems and inflammation in familial combined hyperlipidemia (FCH). Our goal was to evaluate whether XO activity was altered in FCH and if it was related to the inflammatory process represented by NFkB, IL-6 and hsCRP, and assessing the correlation between XO activity and insulin resistance (IR). Method and results 40 Non-related subje…
Endothelium-derived factors in microalbuminuric and nonmicroalbuminuric essential hypertensives
2000
Previous evidence has demonstrated a relationship between growth factors and cardiovascular diseases. This study was aimed at evaluating levels of some endothelium-derived growth factors, and their relationship with microalbuminuria (MAU), in essential hypertension. Ninety-nine mild-moderate essential hypertensives (EH) and 25 healthy controls were studied. All patients underwent 24-h blood pressure monitoring, serum endothelin-1 (ET-1), basic fibroblast growth factor (bFGF) and platelet-derived growth factor (PDGF), and 24-h MAU assays. Later, EH were divided into two subsets consisting of microalbuminurics (MAU >11 microg/min) and nonmicroalbuminurics (MAU <11 microg/min). In microalbumin…