Search results for "blood vessels"
showing 10 items of 94 documents
Vascular labeling of the head and neck vessels : technique, advantages and limitations
2017
Background Vascular staining techniques have been used to describe the vascular structures of several anatomic areas. However, few reports have described this procedure in the head and neck region. This paper describes a head and neck vascular labeling procedure, and describes some of the technical complications that may occur. Material and methods Fifteen specimen cadaver heads were prepared. After drying the vascular system, the internal carotid arteries were ligated and a solution with latex and a gelling agent was injected into the internal carotid arteries and external jugular veins. Two different colors were employed to differentiate arteries from veins. A total of 60ml latex was inje…
Endothelialization and Anticoagulation Potential of Surface-Modified PET Intended for Vascular Applications.
2018
In vascular tissue engineering, great attention is paid to the immobilization of biomolecules onto synthetic grafts to increase bio- and hemocompatibility-two critical milestones in the field. The surface modification field of poly(ethylene terephthalate) (PET), a well-known vascular-graft material, is matured and oversaturated. Nevertheless, most developed methods are laborious multistep procedures generally accompanied by coating instability or toxicity issues. Herein, a straightforward surface modification procedure is presented engineered to simultaneously promote surface endothelialization and anticoagulation properties via the covalent immobilization of gelatin through a photoactivate…
The duodenum in liver cirrhosis: endoscopic, morphological and clinical findings.
1991
Endoscopic studies were performed to determine whether changes occurred in the duodenum related to portal hypertension in patients with liver cirrhosis. The total of 271 patients studied were subdivided into three groups: 83 patients with liver cirrhosis and portal hypertension, 53 with liver cirrhosis but no portal hypertension, and 135 controls. In the duodenum of cirrhotic patients with portal hypertension several changes were observed on endoscopy that were also present in the other two groups. Atrophy and vascular malformations, however, were present only in the duodenum of cirrhotic patients with portal hypertension, although in only a few patients and with statistical significance on…
Automatic segmentation and 3D reconstruction of intravascular ultrasound images for a fast preliminar evaluation of vessel pathologies.
2007
Abstract Intravascular ultrasound (IVUS) imaging is used along with X-ray coronary angiography to detect vessel pathologies. Manual analysis of IVUS images is slow and time-consuming and it is not feasible for clinical purposes. A semi-automated method is proposed to generate 3D reconstructions from IVUS video sequences, so that a fast diagnose can be easily done, quantifying plaque length and severity as well as plaque volume of the vessels under study. The methodology described in this work has four steps: a pre-processing of IVUS images, a segmentation of media–adventitia contour, a detection of intima and plaque and a 3D reconstruction of the vessel. Preprocessing is intended to remove …
Comparison of two techniques (in vivo and ex-vivo) for evaluating the elastic properties of the ascending aorta: Prospective cohort study.
2021
Introduction Aneurysms of the ascending aorta (AA) correspond to a dilatation of the ascending aorta that progressively evolves over several years. The main complication of aneurysms of the ascending aorta is type A aortic dissection, which is associated with very high rates of morbidity and mortality. Prophylactic ascending aorta replacement guidelines are currently based on maximal AA diameter. However, this criterion is imperfect. Stretching tests on the aorta carried out ex-vivo make it possible to determine the elastic properties of healthy and aneurysmal aortic fragments (tension test, resistance before rupture). For several years now, cardiac magnetic resonance imaging (MRI) has pro…
β1 integrin signaling promotes neuronal migration along vascular scaffolds in the post-stroke brain
2017
Cerebral ischemic stroke is a main cause of chronic disability. However, there is currently no effective treatment to promote recovery from stroke-induced neurological symptoms. Recent studies suggest that after stroke, immature neurons, referred to as neuroblasts, generated in a neurogenic niche, the ventricular-subventricular zone, migrate toward the injured area, where they differentiate into mature neurons. Interventions that increase the number of neuroblasts distributed at and around the lesion facilitate neuronal repair in rodent models for ischemic stroke, suggesting that promoting neuroblast migration in the post-stroke brain could improve efficient neuronal regeneration. To move t…
Riociguat versus sildenafil on hypoxic pulmonary vasoconstriction and ventilation/perfusion matching
2017
Introduction Current treatment with vasodilators for pulmonary hypertension associated with respiratory diseases is limited by their inhibitory effect on hypoxic pulmonary vasoconstriction (HPV) and uncoupling effects on ventilation-perfusion (V'/Q'). Hypoxia is also a well-known modulator of the nitric oxide (NO) pathway, and may therefore differentially affect the responses to phosphodiesterase 5 (PDE5) inhibitors and soluble guanylyl cyclase (sGC) stimulators. So far, the effects of the sGC stimulator riociguat on HPV have been poorly characterized. Materials and methods Contraction was recorded in pulmonary arteries (PA) in a wire myograph. Anesthetized rats were catheterized to record …
Stimulation of the AT2 receptor reduced atherogenesis in ApoE−/−/AT1A−/− double knock out mice
2012
AT1 receptor blockers (ARB) and in part ACE inhibitors (ACI) potentially exert beneficial effects on atherogenesis independent of AT1 receptor inhibition. These pleiotropic effects might be related to angiotensin II mediated activation of the AT2 receptor. To analyze this hypothesis we investigated the development of atherosclerosis and the role of ACIs and ARBs in apolipoprotein E-deficient (ApoE(-/-)) mice and in ApoE/AT1A receptor double knockout mice (ApoE(-/-)/AT1A(-/-)). ApoE(-/-) mice and ApoE(-/-)/AT1A(-/-) mice were fed cholesterol-rich diet for 7 weeks. Vascular oxidative stress, endothelial dysfunction, and atherosclerotic lesion formation were evident in ApoE(-/-) mice, but were…
''Comparative Effect of Treadmill Exercise on Mature BDNF Production in Control versus Stroke Rats''
2012
Quirie, Aurore | Hervieu, Marie | Garnier, Philippe | Demougeot, Celine | Mossiat, Claude | Bertrand, Nathalie | Martin, Alain | Marie, Christine | Prigent-Tessier, Anne; International audience; ''Physical exercise constitutes an innovative strategy to treat deficits associated with stroke through the promotion of BDNF-dependent neuroplasticity. However, there is no consensus on the optimal intensity/duration of exercise. In addition, whether previous stroke changes the effect of exercise on the brain is not known. Therefore, the present study compared the effects of a clinically-relevant form of exercise on cerebral BDNF levels and localization in control versus stroke rats. For this purpo…
Direct true lumen cannulation in type A acute aortic dissection: A review of an 11 years’ experience
2020
ObjectivesDirect true lumen cannulation (DTLC) of the aorta is an alternative cardiopulmonary bypass cannulation technique in the context of type A acute aortic dissection (A-AAD). DTLC has been reported to be effective in restoring adequate perfusion to jeopardized organs. This study reports and compares operative outcomes with DTLC or alternative cannulation techniques in a large cohort of patients with A-AAD.MethodsAll patients who underwent surgery for A-AAD between January 2006 and January 2017 in Mainz university hospital were reviewed. The choice of cannulation technique was left to the operating surgeon, however DTLC was our preference in patients who were in state of shock or showe…