Search results for "Respiratory Physiology"
showing 10 items of 363 documents
Influence of respiratory rate and end-expiratory pressure variation on cyclic alveolar recruitment in an experimental lung injury model
2012
Introduction Cyclic alveolar recruitment/derecruitment (R/D) is an important mechanism of ventilator-associated lung injury. In experimental models this process can be measured with high temporal resolution by detection of respiratory-dependent oscillations of the paO2 (ΔpaO2). A previous study showed that end-expiratory collapse can be prevented by an increased respiratory rate in saline-lavaged rabbits. The current study compares the effects of increased positive end-expiratory pressure (PEEP) versus an individually titrated respiratory rate (RRind) on intra-tidal amplitude of Δ paO2 and on average paO2 in saline-lavaged pigs. Methods Acute lung injury was induced by bronchoalveolar lavag…
Respiratory mechanics measured by forced oscillations during mechanical ventilation through a tracheal tube
2011
The forced oscillation technique (FOT) allows the measurement of respiratory mechanics in the intensive care setting. The aim of this study was to compare the FOT with a reference method during mechanical ventilation through a tracheal tube. The respiratory impedance spectra were measured by FOT in nine anaesthetized pigs, and resistance and compliance were estimated on the basis of a linear resistance-compliance inertance model. In comparison, resistance and compliance were quantified by the multiple linear regression analysis (LSF) of conventional ventilator waveforms to the equation of motion. The resistance of the sample was found to range from 6 to 21 cmH(2)O s l(-1) and the compliance…
Sensitivity and specificity of MRA in the diagnosis of neurovascular compression in patients with trigeminal neuralgia
1998
The published rates of operatively confirmed neurovascular compression as the cause for trigeminal neuralgia range from 10 % to nearly 100 %. High-definition magnetic resonance angiography (MRA) was performed in 27 consecutive patients (in 6 cases with 3D reconstructions) to show neurovascular compression preoperatively. The MRA findings were compared with the relationship between the Vth nerve and the surrounding vessels at surgery. In 23 patients MRA showed present neurovascular compression in accordance with surgical findings (18/27 in complete accordance of type and side of vessel, site and direction of compression). One woman had no neurovascular compression either on MRA or intraopera…
VEGF receptor signaling links inflammation and tumorigenesis in colitis-associated cancer.
2010
Inflammation drives expression of VEGFR2, which is expressed on and drives growth of tumor cells in colitis-associated cancer.
The impact of the receptor binding profiles of the vascular endothelial growth factors on their angiogenic features
2013
Abstract Background Vascular endothelial growth factors (VEGFs) are potential therapeutic agents for treatment of ischemic diseases. Their angiogenic effects are mainly mediated through VEGF receptor 2 (VEGFR2). Methods Receptor binding, signaling, and biological efficacy of several VEGFR2 ligands were compared to determine their characteristics regarding angiogenic activity and vascular permeability. Results Tested VEGFR2 ligands induced receptor tyrosine phosphorylation with different efficacy depending on their binding affinities. However, the tyrosine phosphorylation pattern and the activation of the major downstream signaling pathways were comparable. The maximal angiogenic effect stim…
Characterization of Membrane-Bound Cyclic Nucleotide Phosphodiesterases from Bovine Aortic Smooth Muscle
1992
This study reports the isolation and characterization of cyclic nucleotide phosphodiesterases (PDEs) associated with membrane fraction in comparison to cytosolic forms from bovine aorta. DEAE-Sephacel chromatography of a solubilized membrane fraction from a homogenate, prepared under isotonic conditions in the presence of protease inhibitors, yielded one major peak of PDE activity that specifically hydrolyzed cAMP and was not stimulated by calmodulin: It appeared to contain two subtypes of PDE. The first subtype belonged to the cyclic GMP (cGMP)-inhibited PDE family, (PDE III): It had an apparent Km value of 0.4 microM and was potently inhibited by cGMP, LY186126, and cilostamide. The secon…
Endothelial progenitor cells: Are they displaying a function in autoimmune disorders?
2016
Endothelial Progenitor Cells (EPCs) are bone marrow derived cells able to differentiate in mature endothelial cells (EC) contributing to the generation of new vessels, connecting to fibronectin, and forming colonies and/or colony forming units. Since circulating EPCs can be actively considered part of endothelial damage in several cardiovascular diseases and autoimmune disorders the possibility to have a measure for endothelium damage should be considered of interest to predict the patient out-come. At the same time the EPCs proliferative and regenerative role could be considered for therapeutic applications. Studies have been performed to elucidate the role of EPCs in Systemic Sclerosis an…
Correction of the unfavourable effects of vasopressin by nitroglycerin infusion
1982
Nitroglycerin was administered with vasopressin to prevent adverse effects. Vasopressin 0.25U . 70 kg-1 min-1 was infused intravenously in four dogs for 40 minutes, when a venous infusion of nitroglycerin 1.2 micrograms . kg-1 . min-1 was added for 20 minutes. Nitroglycerin 1.2 micrograms . kg-1 . min-1 alone was infused intravenously in another four dogs for 40 minutes. The venous blood pressures (mesenteric and central) and arterial pressures (mesenteric and femoral), the electrocardiogram and arterio-venous difference were recorded. Nitroglycerin was shown to annul the unfavourable effects of vasopressin without altering its efficacy upon portal pressure.
"Table 2" of "Measurement of differential Z / gamma* + jet + X cross sections in p anti-p collisions at s**(1/2) = 1.96-TeV"
2008
Measured cross section as a function of the jet rapidity.
Fragmented Qrs Complex on a 12-Lead Ecg in Patients With Acute Myocardial Infarction: A MRI Study
2011
International audience; The goal of this study is to investigate the relationship between a fragmented QRS complex (fQRS) and parameters of infarct size (IS) and no reflow assessed by cardiac magnetic resonance (CMR) in patients with acute myocardial infarction.