Search results for "Artery"
showing 10 items of 2026 documents
Scalp, basal epidural and intravascular far-field recordings after median nerve stimulation: evidence for a separate N18a potential
2000
Far-field somatosensory evoked potentials (SSEPs) after median nerve stimulation were recorded from scalp- (Fz), epidural- (ED) and intravascular electrodes (basilar artery [Bas]) to study the nature of the controversial N18a component of the widespread N18 potential. In healthy volunteers frequently an N18a potential was recorded at Fz. Simultaneous Fz and ED recordings at the pontomesencephalic junction as well as Bas-recordings at the caudal basilar artery showed N18a components identical in latency and shape. With intravascular recordings the shapes differed between the top of the basilar artery and the caudal artery recordings. These findings support the existence of a separate N18a po…
Analysis of blood flow in one dimensional elastic artery using Navier-Stokes conservation laws
2017
En los últimos años, la simulación computacional en ámbitos médicos ha aumentado notablemente en múltiples ramas de la ciencia, desde modelización a métodos numéricos, pasando por informática. Los principales objetivos de esta disciplina incipiente son comprobar hipótesis antes de una intervención, o ver qué efecto podría tener un medicamento antes de tomarlo, entre otros. En este trabajo deduciremos desde los principios físicos más básicos un modelo unidimensional para la simulación del flujo sanguíneo en arterias elásticas. Proporcionaremos un marco histórico, así como una revisión de este tipo de modelos. Estudiaremos también desde el punto de vista del análisis matemático las ecuaciones…
The Length of Leukocyte and Femoral Artery Telomeres in Patients with Peripheral Atherosclerosis.
2022
The length of telomeres (TLs) that protect chromosome ends may reflect the age of cells as well as the degree of genetic material damage caused by external factors. Since leukocyte telomere length is associated with cardiovascular diseases, the aim of this study was to evaluate whether leukocyte TL reflects femoral artery wall telomeres of patients with atherosclerosis and lower limb ischemia. Samples of femoral artery wall and blood were collected from 32 patients qualified to surgical revascularization. The analysis included blood and artery wall telomere length measurement and biochemical parameters. The study indicated that there was a moderate correlation between artery wall TL and leu…
Synchrony Analysis of Unipolar Cardiac Mapping during Ventricular Fibrillation
2014
Ventricular Fibrillation (VF) is one of the main causes of death in developed countries. Recent studies have shown that fibrillation have a complex organization scheme. This work uses three measures of synchrony to characterize three groups of rabbit hearts. These groups consist of rabbits trained with physical exercise (N=7), untrained rabbits treated with a drug (N=13) and a control group of untrained rabbits (N=15). Cardiac mapping records were acquired using a 240-electrode array placed on left ventricle of isolated rabbit hearts, and VF was induced pacing at increasing rates. Two acquisitions were performed: maintained perfusion, and ischemic damage produced by an artery ligation. The …
Anti-angiogenic drug loaded liposomes: Nanotherapy for early atherosclerotic lesions in mice.
2018
Este artículo se encuentra disponible en la página web de la revista en la siguiente URL: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0190540 También participan en la elaboración de este artículo científico: Aracely Calatayud-Pascual, Alicia López-Castellano, Elena P. Albelda, Enrique García-España, Luis Martí-Bonmatí, Juan C. Frias y M. Teresa Albelda. Fumagillin-loaded liposomes were injected into ApoE-KO mice. The animals were divided into several groups to test the efficacy of this anti-angiogenic drug for early treatment of atherosclerotic lesions. Statistical analysis of the lesions revealed a decrease in the lesion size after 5 weeks of treatment.
Assessment of coronary artery bypass grafts: value of different breath-hold MR imaging techniques.
1999
Our aim was to evaluate the patency of coronary artery bypass grafts and to detect graft stenosis using different breath-hold MR imaging techniques.Twenty-two patients with 59 grafts (14 internal mammary artery grafts and 45 saphenous vein grafts) and 76 distal anastomoses (singular and sequential grafts) were studied using a 1.5-T scanner. A two-dimensional T2-weighted breath-hold half-Fourier acquisition single-shot turbo spin echo (HASTE) sequence and a three-dimensional breath-hold contrast-enhanced MR angiography sequence (fast imaging with steady-state free precession) were performed. For MR angiography, a bolus of 20 ml of gadopentetate dimeglumine was used. Time delay for contrast i…
Late gadolinium enhancement-cardiovascular magnetic resonance identifies coronary artery disease as the aetiology of left ventricular dysfunction in …
2009
Aims We evaluated the ability of late gadolinium enhancement (LGE) using cardiovascular magnetic resonance (CMR) to identify acute new-onset heart failure (HF) with left ventricular systolic dysfunction (LVSD), whether or not in relation to underlying coronary artery disease (CAD), in patients with no clinical evidence of associated ischaemic cardiomyopathy. Methods and results Hundred consecutive patients admitted with acute new-onset decompensated HF and EF ,40%, with no clinical or electrocardiographic data suggestive of CAD. The patients were classified according to the presence or absence of significant CAD (stenosis � 70% in at least one major vessel). Twenty-one patients (21%) had si…
Quantification of resting myocardial blood flow in a pig model of acute ischemia based on first-pass MRI
2005
Qualitative and semiquantitative contrast-enhanced (CE) dynamic perfusion MRI techniques are established as noninvasive diagnostic means of assessing coronary artery disease. However, to date quantification of myocardial blood flow (MBF) has not reached the same acceptance as MBF quantification with nuclear techniques. To validate quantification of MBF at rest using the extracellular contrast agent (CA) Gd-DTPA, we performed an animal study in a pig model of acute myocardial ischemia. We quantified MBF from MRI data with a mathematical model (MMID4) of the underlying vasculature. These MBF results were subsequently compared with the results from fluorescent microspheres. The study showed a …
Extremitätenerhalt durch pedalen In-situ-Bypass beim diabetischen Fußsyndrom
2003
INTRODUCTION: Treatment of the ischemic diabetic foot syndrome still represents a medical and economic challenge. Contrary to the aims of the Saint Vincent declaration a dramatic reduction of major amputations in Germany was not noted, although in the diabetic patients the predominant type of tibial artery occlusion allows construction of pedal bypasses for limb salvage. METHOD: In patients with ischemic diabetic foot syndrome following angiographic evaluation of the ischemic limb, the indication for surgical revascularisation of patent pedal arteries was established. The in-situ technique was preferred in the presence of a suitable ipsilateral greater saphenous vein whenever possible. Reva…
Potential Functional Significance of Brain-Type and Muscle-Type Nitric Oxide Synthase I Expressed in Adventitia and Media of Rat Aorta
1999
Abstract —Skeletal muscle and myocardium express μNOS I, an elongated splice variant of neuronal-type nitric oxide (NO) synthase (NOS I), and NOS III, endothelial-type NO synthase, respectively. This study was designed to elucidate whether vascular smooth muscle also contains a constitutively expressed NO synthase isoform. In the rat, μNOS I contains an insert of 102 nucleotides after nucleotide 2865 of the cDNA, yielding a protein of 164 kd. Reverse transcription-polymerase chain reaction with primers flanking this insert and with insert-specific primers indicated that endothelium-denuded rat aorta expresses both brain-type NOS I and μNOS I. RNase protection analyses with an antisense RNA…