Search results for "aorta"
showing 10 items of 458 documents
The compliance modelling of the pathology aorta of the type of aneurism
2015
The Abdominal Aorta Aneurysm (AAA) is a pathology that is defined by a localized and permanent dilation of the artery and which involves over 8.8% of the seniors. Currently, when a patient has a dilatation of the aorta leading to a surgery because of the rupture risk, the therapeutic decision is made depending on the diameter of the aneurysm. To determine this diameter, it is usually conducted an examination by medical imaging (ultrasound, CT, MRI...). However, it notes that the diagnosis can’t be satisfied with a single dimensional measurement face to induced risks: first of all, when the diameter exceed a certain growth, the risk of rupture can reach 50% but more than 5% of surgical proce…
Characterization of a Computerized Assay for Rapid and Easy Determination of Leukocyte Adhesion to Endothelial Cells
2005
We report on a facile and rapid computerized in-vitro assay for the quantification of leukocyte adhesion to endothelial cells under static conditions using bovine polymorphonuclear neutrophils (PMN) or human leukaemic Mono Mac 6 cells (MM6) and bovine aorta endothelial cells (BAEC). Images of leukocytes adherent to BAEC monolayers grown in microtiter plates were obtained by a digital camera attached to a conventional microscope and transferred to the public domain NIH ImageJ program for analysis. Using individually adapted program routines adherent leukocytes are easily discriminated and reproducibly quantified. The results obtained with our assay correspond to previous findings and demonst…
A simplified method to quantitate atherosclerosis in the rabbit aorta.
2001
A simple method to quantitatively evaluate atherosclerosis in the rabbit aorta by measuring macroscopic lesion areas (%) was attempted in the present study. Ten female New Zealand white rabbits were fed on a cholesterol-rich diet (5/1000 g of food) during 4 months. Five of them were oophorectomized at the beginning and all were sacrificed at the end. Total levels of cholesterol increased from 50.7+/-14.7 mg/dl to 782.8+/-296.0. No significant differences were observed between oophorectomized and intact rabbits. At 4 months, the cholesterol-rich diet caused in both, intact and oophorectomized rabbits, atherosclerotic lesions affecting 17 and 46% of the aortic surface, respectively. This meth…
Local ex-vivo evaluation of the biomechanical properties of the ascending aortic aneurysms
2019
Introduction Currently, surgical recommendations for aneurysm of the ascending aorta (AsAA) are based on the maximum diameter of the ascending aorta, but this factor is not reliable. Understanding the biomechanical properties of the aorta could lead to improve the prediction of the development of an AsAA. The aim of this study is to obtain the local patient specific elastic modulus distribution of the AsAA from a biaxial tensile test. Methods Pathologic ascending aortic tissue samples (n = 10) were obtained from patients undergoing elective surgical repair of AsAA ( Table 1 ). All the aortic wall samples were partitioned related to medial, posterior, lateral, and anterior quadrants. Each As…
Aortopexy in esophageal atresia: Long-term experience of a parent support group
2001
Abstract Purpose: The aim of this study was to obtain the parents' view of aortopexy after esophageal atresia. Methods: A questionnaire was completed by the parents of 24 former patients, now aged from 1 to 15 years (average, 8.9; median, 9.0 years). The respondents were all members of a support group. Results: The median age of the patients receiving aortopexy was 4 months. The 24 procedures were performed in 16 different hospitals. The subjects had experienced a median of 3 apneic attacks. Technical complications occurred in 4 of the 24 children. In 71%, aortopexy was an immediate success. Conclusion: Despite its low success rate compared with centers with large cumulative experience, 90%…
Functional characterization of α1 -adrenoceptor subtypes in vascular tissues using different experimental approaches:a comparative study
2003
The α1-adrenergic responses of rat aorta and tail artery have been analysed measuring the contractility and the inositol phosphate (IP) formation induced by noradrenaline. Three antagonists, prazosin, 5-methylurapidil (α1A selective) and BMY 7378 (α1D selective) have been used in different experimental procedures. Noradrenaline possesses a greater potency inducing contraction and IP accumulation in aorta (pEC50-contraction=7.32±0.04; pEC50-IPs=6.03±0.08) than in the tail artery (pEC50-contraction=5.71±0.07; pEC50-IPs=5.51±0.10). Although the maximum contraction was similar in both tissues (Emax-tail=619.1±55.6 mg; Emax-aorta-698.2±40.8 mg), there were marked differences in the ability of th…
Failure of 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) to inhibit soluble guanylyl cyclase in rat ventricular cardiomyocytes
1999
The effects of 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), an inhibitor of soluble guanylyl cyclase (sGC), were investigated in aortic rings and ventricular cardiomyocytes from rats. The production of cyclic GMP was stimulated by NO•-donors or carbachol. Additionally, the effects of ODQ were studied in cytosolic extracts from both tissues in which the cyclic GMP production was stimulated by S-nitroso-N-acetylpenicillamine (SNAP). In endothelium-intact aortic rings, SNAP (100 μM), 2,2′-(hydroxynitrosohydrazino)bis-ethanamine (DETA NONOate; 100 μM), or carbachol (10 μM) increased cyclic GMP levels about 4 fold. These effects were abolished by ODQ (50 μM). In cardiomyocytes, SNAP (100 μ…
Activation of soluble guanylyl cyclase by YC-1 in aortic smooth muscle but not in ventricular myocardium from rat
1997
1 The effects of YC-1 (3-(5′-hydroxymethyl-2′-furyl)-1-benzyl indazole), an activator of soluble guanylyl cyclase, on tension, levels of cyclic GMP and cyclic AMP, and cardiac L-type Ca2+-current (ICa(L)) were investigated in aortic smooth muscle and ventricular heart muscle from rat. 2 YC-1 (0.1–30 μM) induced a concentration-dependent relaxation in aortic rings precontracted with phenylephrine (3 μM). The relaxant effects of YC-1 were reversed by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (30 μM; ODQ), potentiated by zaprinast (10 μM) and antagonized by Rp-8-Br-cGMPS (100 μM). 3 In ventricular heart muscle strips, YC-1 (30 μM) exhibited no effects on force of contraction (Fc) in the abse…
Pathological role of a constitutively active population of α1D -adrenoceptors in arteries of spontaneously hypertensive rats
2002
The role of a constitutively active population of α1D-adrenoceptors was analysed in arteries obtained from spontaneously hypertensive rats (SHR) and controls (WKY) divided into three groups: young prehypertensive, adult hypertensive, and adult animals chronically treated with captopril (50 mg kg−1 per day orally) in order to prevent the hypertensive state. In adult SHR, a significant increase in BMY 7378 potency (not in prazosin potency) was observed in aorta, mesenteric artery, and the first and second branches of the small mesenteric arteries with respect to WKY rats. This difference was not observed in iliac and tail arteries, which suggests an increased functional role of α1D-adrenocept…
Synthesis of recombinant atrial natriuretic peptide (rANP) using hybrid fusion protein-phage fr coat/ANP (CP/ANP).
1997
Abstract Baumanis, V., I. Jansone, A. Skangals, I. Mandrika and V. Berzins. Synthesis of recombinant atrial natriuretic peptide (rANP) using hybrid fusion protein-phage fr coat/ANP (CP/ANP). Peptides 18(8) 1229–1235, 1997.—Recombinant atrial natriuretic peptide (rANP) was expressed in and isolated from E. coli. rANP was purified using HPLC. Amino acid analysis, partial sequencing, and molecular mass were determined. Fused protein was used to rise polyclonal antibodies and to develop of immunoenzymatic assays of rANP and CP/ANP. Experiments were designed to study rANP effects on isolated rabbit aortic strips and to examine hypotensive, diuretic, and natriuretic activity, as well as renal cre…