Search results for "Artery"
showing 10 items of 2026 documents
Response to Anti-human IgE in Human Pulmonary Arteries: Regulation by Endothelium
1993
Initial reports concerning anaphylactic reactions in the lung have demonstrated that histamine is released, and this mediator may be responsible for the severe hypotension observed in vivo in sensitized animals. However, those mechanisms involved in the antigen-vascular interactions have not been elucidated. Human isolated pulmonary arterial preparations relaxed when challenged with anti-human IgE (a-IgE). This response was associated with a release of histamine and PGI2. Both the relaxation and the release of PGI2 were attenuated by removal of the endothelium or by prior treatment of the tissues with chlorpheniramine. Indomethacin also significantly reduced the relaxations produced by a-Ig…
Pulmonary vascular endothelium: The orchestra conductor in respiratory diseases
2018
The European Respiratory Society (ERS) Research Seminar entitled “Pulmonary vascular endothelium: orchestra conductor in respiratory diseases - highlights from basic research to therapy” brought together international experts in dysfunctional pulmonary endothelium, from basic science to translational medicine, to discuss several important aspects in acute and chronic lung diseases. This review will briefly sum up the different topics of discussion from this meeting which was held in Paris, France on October 27–28, 2016. It is important to consider that this paper does not address all aspects of endothelial dysfunction but focuses on specific themes such as: 1) the complex role of the pulmon…
Influence of endothelial nitric oxide on neurogenic contraction of human pulmonary arteries.
1995
The present study was designed to investigate the contribution of the endothelium and that of the L-arginine pathway on the contractile responses of isolated human pulmonary arteries to electrical field stimulation (EFS) and noradrenaline. Isometric tension was measured in artery rings obtained from portions of human lung after thoracic surgery for removal of lung carcinoma (18 patients). Electrical field stimulation (EFS) induced frequency-dependent contractions of isolated human pulmonary arteries which were abolished by tetrodotoxin, guanethidine and prazosin (all at 10(-6) M). The increases in tension were of greater magnitude in arteries denuded of endothelium. NG-nitro-L-arginine meth…
Computer tomography features of pulmonary vascular involvement in Behçet's disease
2019
Behçet’s disease is a chronic and multisystemic inflammatory vascular disease of unknown etiology, affecting vessels of all kinds and sizes. The involvement of the vascular system is observed in approximately 5-30% of patients. The most frequent vascular manifestations are venous thrombosis followed by arterial aneurysms and arterial thrombosis. The identification of vascular involvement is very important for prognosis, indeed the rupture of an arterial aneurysm represents the leading cause of sudden death in patients with Behçet’s disease. Computed tomography (CT) plays a crucial role in the identification and in the follow-up of vascular involvement. In this paper, we report the case of a…
Evidence for a negative inotropic effect of obesity in human myocardium?
2009
Objective: The present study was performed as an attempt to analyze the relationship between body weight and human myocardial performance. As overweight is frequently associated with hypertension, stenosis of epimyocardial coronary arteries and other factors that influence myocardial performance, the experimental model of isolated human atrial myocardium was selected. Atrial contractile performance does neither depend on the extent of stenosis of epicardial coronary arteries nor on the degree of hypertension and its secondary pathology. Methods:Rightatrialmusclepreparations(0.5 6 mm)of183patientsundergoingcoronaryarterybypasssurgerywereelectricallystimulatedat optimal length. Active tension…
Obstructive sleep apnoea in acute coronary syndrome.
2019
Obstructive sleep apnoea (OSA) syndrome affects about 13% of the male and 7–9% of the female population. Hypoxia, oxidative stress and systemic inflammation link OSA and cardiovascular and metabolic consequences, including coronary artery disease. Current research has identified several clinical phenotypes, and the combination of breathing disturbances during sleep, systemic effects and end-organ damage might help to develop personalised therapeutic approaches. It is unclear whether OSA is a risk factor for acute coronary syndrome (ACS) and might affect its outcome. On the one hand, OSA in patients with ACS may worsen prognosis; on the other hand, OSA-related hypoxaemia could favour the dev…
Effects of the novel polymer gel LeGoo on human internal thoracic arteries.
2011
Purpose Established hemostatic devices can injure vessel wall integrity. LeGoo (Pluromed, Woburn, MA), a novel poloxamer gel with reverse thermosensitive properties, is a new device for temporary occlusion of blood vessels. The present study investigated the effects of LeGoo on vascular function and morphology. Description The distal end of the human internal thoracic artery was used to assess vascular function of LeGoo-applied segments in organ bath experiments and by scanning electron microscopy. Evaluation After LeGoo application, both maximal contractile responses to noradrenaline and endothelium-dependent relaxant responses to acetylcholine were significantly reduced. Scanning electron…
A particular phenotype of ascending aorta aneurysms as precursor of type A aortic dissection.
2012
Objectives: We aimed to identify a phenotype of ascending thoracic aortic aneurysm (TAA), which, more than others, evolves into type A dissection (TAD). Methods: Aortic specimens were obtained from patients undergoing surgical repair of TAA and TAD (108 and 26, respectively). Histopathological and immunohistochemical analyses were performed by using adequate tissue specimens, appropriate techniques and criteria. Results: We identified the three following TAA phenotypes: phenotype I (cystic medial degeneration balanced by a substitutive fibrosis, in absence of medial apoptosis and with a faint collagenase concentration), phenotype II (cystic medial degeneration of higher grade, respectively,…
Endothelin receptor expression in idiopathic pulmonary arterial hypertension: effect of bosentan and epoprostenol treatment.
2011
Endothelin receptor antagonists are used to treat idiopathic pulmonary arterial hypertension (IPAH), but human pulmonary arterial endothelin receptor expression is not well defined. We hypothesised that disease and treatment would modify normal receptor distribution in pulmonary resistance arteries of children. Using immunohistochemistry and semiquantitative analysis, we investigated endothelin receptor subtypes A and B (ET(A) and ET(B), respectively), and endothelial nitric oxide synthase (eNOS) expression in peripheral pulmonary arteries of tissue from untreated children with IPAH (n=7), following extended combined bosentan and epoprostenol therapy (n=5) and from normal subjects (n=5). Cl…
Survival and reinterventions after isolated proximal aortic repair in acute type A aortic dissection.
2018
OBJECTIVES Conventional treatment for acute type A dissection is the replacement of the ascending aorta. This study demonstrates the results of a conventional approach with isolated proximal repair combined with concomitant endovascular procedures. METHODS Replacement of the ascending aorta with or without an open distal anastomosis was defined as isolated proximal repair and was performed in 562/588 patients between January 2004 and June 2017. A total of 68% were DeBakey type I and 32% were DeBakey type II aortic dissections. Concomitant procedures were thoracic endovascular aortic repair (3.6%); visceral, renal and iliac stents (2%); and peripheral bypasses (1.1%). Mean follow-up was 4.6 …