Search results for "techniques"
showing 10 items of 4426 documents
Soot-exposed mononuclear cells increase inflammatory cytokine mRNA expression and protein secretion in cocultured bronchial epithelial cells.
2000
<i>Background:</i> Soot particles are air pollutants capable of inducing airway and lung parenchymal injury. Mononuclear and bronchial epithelial cells are central to the maintenance of homeostasis and inflammation in the airways. <i>Objectives:</i> The aim of this study was to evaluate the contribution of mononuclear cells to the release of inflammatory mediators by bronchial epithelial cells. <i>Methods:</i> To model the in vivo situation, an in vitro system of cocultured blood monocytes and BEAS-2B cells was established in a transwell system. Blood monocytes were exposed to soot particles (FR 101) at concentrations of up to 100 μg/10<sup>6</su…
Implantation of Gore-Tex chordae on aortic valve leaflet to treat prolapse using "the chordae technique": surgical aspects and clinical results.
2008
Background Repair of prolapsed aortic valve leaflets has been considered a challenging technique for cardiac surgeons. In this paper we describe our surgical approach, "the chordae technique." It consists of the correction of aortic cusp prolapse by shortening the free margin length and of an adjustment of the leaflets coaptation height by anchoring the prolapsing cusp to the aortic wall at the sinotubular junction level. Methods Between February 2003 and December 2006, 26 patients with one or more prolapsed aortic leaflets underwent surgical repair using the new approach. The mean age of patients was 55 ± 10 years. There were 10 (38.5%) patients with grade II aortic valve regurgitation, 4 …
Hypoxia-induced dysfunction of rat diaphragm
2004
Contains fulltext : 47331.pdf (Publisher’s version ) (Closed access) Oxidants may play a role in hypoxia-induced respiratory muscle dysfunction. In the present study we hypothesized that hypoxia-induced impairment in diaphragm contractility is associated with elevated peroxynitrite generation. In addition, we hypothesized that strenuous contractility of the diaphragm increases peroxynitrite formation. In vitro force-frequency relationship, isotonic fatigability, and nitrotyrosine levels were assessed under hypoxic (Po(2) approximately 6.5 kPa) and hyperoxic (Po(2) approximately 88.2 kPa) control conditions and also in the presence of authentic peroxynitrite (60 min), ebselen (60 min), and t…
‘Soft’ Snaring of the Coronary Artery in Minimally-Invasive Coronary Surgery
1998
A technique is described that allows a simple and safe temporary occlusion of the coronary artery in beating heart procedures using monofilament stay sutures underlaid with small pericardial pads. Postoperative serial levels of Troponin I remained low (<4 ng/L) and control angiography revealed no stenosis in the distal coronary artery.
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…
Roflumilast N-oxide inhibits bronchial epithelial to mesenchymal transition induced by cigarette smoke in smokers with COPD.
2014
Abstract Background Epithelial to mesenchymal transition (EMT) is under discussion as a potential mechanism of small airway remodelling in COPD. In bronchial epithelium of COPD and smokers markers of EMT were described. In vitro, EMT may be reproduced by exposing well-differentiated human bronchial epithelial cells (WD-HBEC) to cigarette smoke extract (CSE). EMT may be mitigated by an increase in cellular cAMP. Objective This study explored the effects of roflumilast N-oxide, a PDE4 inhibitor on CSE-induced EMT in WD-HBEC and in primary bronchial epithelial cells from smokers and COPD in vitro. Methods WD-HBEC from normal donors were stimulated with CSE (2.5%) for 72 h in presence of roflum…
Nanocomplexes for gene therapy of respiratory diseases: Targeting and overcoming the mucus barrier
2015
Gene therapy, i.e. the delivery and expression of therapeutic genes, holds great promise for congenital and acquired respiratory diseases. Non-viral vectors are less toxic and immunogenic than viral vectors, although they are characterized by lower efficiency. However, they have to overcome many barriers, including inflammatory and immune mediators and cells. The respiratory and airway epithelial cells, the main target of these vectors, are coated with a layer of mucus, which hampers the effective reaching of gene therapy vectors carrying either plasmid DNA or small interfering RNA. This barrier is thicker in many lung diseases, such as cystic fibrosis. This review summarizes the most impor…
Towards the determination of isoprene in human breath using substrate-integrated hollow waveguide mid-infrared sensors
2014
Selected volatile organic compounds (VOCs) in breath may be considered biomarkers if they are indicative of distinct diseases or disease states. Given the inherent molecular selectivity of vibrational spectroscopy, infrared sensing technologies appear ideally suitable for the determination of endogenous VOCs in breath. The aim of this study was to determine that mid-infrared (MIR; 3-20 µm) gas phase sensing is capable of determining isoprene in exhaled breath as an exemplary medically relevant VOC by hyphenating novel substrate-integrated hollow waveguides (iHWG) with a likewise miniaturized preconcentration system. A compact preconcentrator column for sampling isoprene from exhaled breath …
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…
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…