Search results for "Artery"

Observations of time-based measures of flow-mediated dilation of forearm conduit arteries: implications for the accurate assessment of endothelial fu…

2010

Endothelium-dependent flow-mediated dilation (FMD) is measured as the increase in diameter of a conduit artery in response to reactive hyperemia, assessed either at a fixed time point [usually 60-s post-cuff deflation (FMD60)] or as the maximal dilation during a 5-min continuous, ECG-gated, measurement (FMDmax-cont). Preliminary evidence suggests that the time between reactive hyperemia and peak dilation (time to FMDmax) may provide an additional index of endothelial health. We measured FMDmax-cont, FMD60, and time to FMDmax in 30 young healthy volunteers, 22 healthy middle-aged adults, 16 smokers, 23 patients with hypertension, 40 patients with coronary artery disease, and 22 patients wit…

Correlation of cerebral blood flow and MCA flow velocity measured in healthy volunteers during acetazolamide and CO2 stimulation

1995

Abstract The assessment of the cerebrovascular reserve capacity (RC) has become a widely used tool in the management of cerebrovascular disease. Discrepancies become obvious, however, if results obtained with different methods are compared. Aim of the present study, therefore, was to compare blood velocity and cerebral perfusion data in the same group of healthy test persons. In 32 volunteers regional cerebral blood flow (rCBF) was measured with the 133 Xe-inhalation method. F1 as grey matter flow and the initial slope index (ISI) were computed. Simultaneously flow velocity in the middle cerebral artery (V MCA ) was assessed by transcranial Doppler sonography (TCD). Measurements were perfor…

High progesterone levels are associated with family history of premature coronary artery disease in young healthy adult men.

2019

Background & aimsThe offspring of patients with premature coronary artery disease (P-CAD) are at higher risk for cardiovascular disease, compared with subjects without a family history (FH) of P-CAD. The increased risk for cardiovascular disease in subjects with FH of early-onset CAD results from unfavorable genetic variants as well as social, behavioral and environmental factors, which are more prevalent in this group. Previous studies have shown that specific sex hormone levels may be associated with the risk of cardiovascular disease. The aim of this study was to compare wide range of biochemical marker levels including i.e. the levels of luteinizing hormone (LH), follicle-stimulating ho…

β2-adrenoreceptors control human skin microvascular reactivity.

2021

Topical α1- and α2-adrenoreceptor (ADRA1 and 2) agonists are effective in alleviating permanent vasodilation and facial erythema associated with rosacea by inducing skin vasoconstriction. Although β-adrenoreceptor (ADRB) antagonists are used off-label for rosacea, pharmacological and pharmacodynamic data pertaining to these receptors in skin micro-vessels are lacking. Objectives: To analyse the expression of different adrenergic receptors and their contribution to vasoreactivity in skin micro-vessels. Small arteries (500-800 μm) and arterioles (<200 μm) were studied in human foreskin tissue. Specifically, ADR-A1, -A2, -B1 and -B2 expression was assayed by immunofluorescence, polymerase chai…

A custom image-based analysis tool for quantifying elastin and collagen micro-architecture in the wall of the human aorta from multi-photon microscopy

2014

The aorta possesses a micro-architecture that imparts and supports a high degree of compliance and mechanical strength. Alteration of the quantity and/or arrangement of the main load-bearing components of this micro-architecture - the elastin and collagen fibers - leads to mechanical, and hence functional, changes associated with aortic disease and aging. Therefore, in the future, the ability to rigorously characterize the wall fiber micro-architecture could provide insight into the complicated mechanisms of aortic wall remodeling in aging and disease. Elastin and collagen fibers can be observed using state-of-the-art multi-photon microscopy. Image-analysis algorithms have been effective at…

V2-receptor–mediated relaxation of human renal arteries in response to desmopressin

1999

The effects of deamino-8-D-arginine vasopressin (desmopressin), a V2 receptor antidiuretic agonist, were studied in isolated rings from branches of renal arteries obtained from 22 patients undergoing nephrectomy. The rings were suspended in organ bath chambers for isometric recording of tension. In precontracted rings with norepinephrine (10(-6) to 3 x 10(-6) mol/L), desmopressin (10(-11) to 3 x 10(-7) mol/L) caused endothelium-dependent relaxation (81%+/-4% reversal of the initial contraction in arteries with endothelium; 20%+/-4% in arteries without endothelium; P < .05). The relaxation to desmopressin in rings with endothelium was reduced significantly by indomethacin (10(-6) mol/L) and …

Biomechanical implications of excessive endograft protrusion into the aortic arch after thoracic endovascular repair

2015

Endografts placed in the aorta for thoracic endovascular aortic repair (TEVAR) may determine malappositioning to the lesser curvature of the aortic wall, thus resulting in a devastating complication known as endograft collapse. This premature device failure commonly occurs in young individuals after TEVAR for traumatic aortic injuries as a result of applications outside the physical conditions for which the endograft was designed. In this study, an experimentally-calibrated fluid-structure interaction (FSI) model was developed to assess the hemodynamic and stress/strain distributions acting on the excessive protrusion extension (PE) of endografts deployed in four young patients underwent TE…

RUPTURE OF A LEFT SINUS OF VALSALVA ANEURYSM INTO THE PULMONARY ARTERY.

2006

Sinus of Valsalva aneurysm is a rare congenital defect and the diagnosis is usually made after it ruptures. Very few cases of non-complicated sinus of Valsalva aneurysm have been published. The anomaly most often involves the right coronary sinus and less frequently the non-coronary sinus. A case with left sinus of Valsalva has not been reported. Since the aortic valve occupies a central position in the base of the heart, rupture of a sinus of Valsalva aneurysm can occur in any of the four heart chambers. Rupture into the pulmonary artery is very rare and is mostly associated with other congenital cardiopathies. ª 2005 The European Society of Cardiology. Published by Elsevier Ltd. All right…

Lorcainide. I. Saturable presystemic elimination.

1979

Non invasive evaluation of endothelial function in patients with Anderson-Fabry disease.

2005

AIM: Fabry's disease is an X-linked recessive abnormality of glycosphingolipid metabolism. Increased levels of endothelial prothrombotic factors have recently been demonstrated in Fabry's disease, whereas endothelial function has not been studied using high resolution ultrasound. METHODS: We enrolled 6 patients (4 male, 2 female; mean age, 37 years) and 12 sex matched control subjects (mean age, 37 years). Patients' exclusion criteria included a prior history of cardiac disease, diabetes and treated or untreated hypertension. Patients underwent: anamnesis, physical examination, EKG, 2-dimensional echocardiography with tissue Doppler, measurement of body weight and height, blood pressure. Bi…