Search results for "pulmonary circulation"
showing 10 items of 21 documents
The influence of Albunex on the pulmonary circulation in patients with pulmonary hypertension or left heart failure.
1996
To determine the safety of the ultrasound contrast agent Albunex, its influence on right and left heart haemodynamics in patients with pulmonary artery hypertension or left heart failure was assessed after intravenous injection. Patients with a left ventricular ejection fraction smaller than 40% or a systolic pulmonary artery pressure greater than 40 mmHg received 0.08 and 0.22 ml.kg -1 Albunex and 10 ml albumin in random order during right heart catheterization and transthoracic echocardiography. Right atrial, systolic and diastolic pulmonary artery and capillary wedge pressures were measured at 3 min and 5 min and cardiac output at 5 min after the intravenous injection of Albunex and cont…
Magnetic resonance imaging of dissolved hyperpolarized 129Xe using a membrane-based continuous flow system.
2009
Abstract A technique for continuous production of solutions containing hyperpolarized 129Xe is explored for MRI applications. The method is based on hollow fiber membranes which inhibit the formation of foams and bubbles. A systematic analysis of various carrier agents for hyperpolarized 129Xe has been carried out, which are applicable as contrast agents for in vivo MRI. The image quality of different hyperpolarized Xe solutions is compared and MRI results obtained in a clinical as well as in a nonclinical MRI setting are provided. Moreover, we demonstrate the application of 129Xe contrast agents produced with our dissolution method for lung MRI by imaging hyperpolarized 129Xe that has been…
Differential adhesion of polymorphous neutrophilic granulocytes to macro- and microvascular endothelial cells under flow conditions.
2002
<i>Objective:</i> As one of the important active barriers in the human organism, endothelial cells (EC) play a central role in the biological reaction to a variety of stimuli, e.g. during the induction and regulation of inflammation, as well as in the reaction to transplantation and biomaterial implantation. In the study of endothelial function, the most widely used in vitro model is that of human umbilical vein EC (HUVEC), i.e. an EC type of embryonic and macrovascular origin. However, many of the important pathological processes occur at microvascular level, thus questioning the validity of the HUVEC model. Moreover, the morphological and functional heterogeneity of the endoth…
A comparison of micropore membrane inlet mass spectrometry–derived pulmonary shunt measurement with riley shunt in a porcine model
2009
The multiple inert gas elimination technique was developed to measure shunt and the ratio of alveolar ventilation to simultaneous alveolar capillary blood flow in any part of the lung (V(A)'/Q') distributions. Micropore membrane inlet mass spectrometry (MMIMS), instead of gas chromatography, has been introduced for inert gas measurement and shunt determination in a rabbit lung model. However, agreement with a frequently used and accepted method for quantifying deficits in arterial oxygenation has not been established. We compared MMIMS-derived shunt (M-S) as a fraction of total cardiac output (CO) with Riley shunt (R-S) derived from the R-S formula in a porcine lung injury model.To allow a …
FVIII production by human lung microvascular endothelial cells
2006
While extrahepatic factor VIII (FVIII) synthesis suffices for hemostasis, the extrahepatic production sites are not well defined. We therefore investigated the ability of the human lungs to produce FVIII. Lungs from heart-beating donors who were declined for transplantation were perfused and ventilated in an isolated reperfusion model for 2 hours. A progressive accumulation of FVIII and von Willebrand factor (VWF) was recorded in the perfusion medium in 3 of 4 experiments. By contrast, factor V, fibrinogen, and immunoglobulin G (IgG) levels remained constant during the perfusion period, indicating that the accumulation of FVIII and VWF was not due to diffusion from the intercellular medium …
Bidirectional Glenn and antegrade pulmonary blood flow: temporary or definitive palliation?
2008
Background We sought to investigate the role of the bidirectional Glenn with antegrade pulmonary blood flow in the surgical history of children with univentricular hearts. Methods A series of 246 patients, from three joint institutions, having univentricular heart with restricted but not critical pulmonary blood flow received a bidirectional cavopulmonary shunt with additional forward pulmonary blood flow. All patients have been studied according to their progression, or not, to Fontan operation. Two hundred and eight (84.5%) patients underwent bidirectional cavopulmonary anastomosis as primary palliation. Twenty patients (8.1%) with previous pulmonary artery banding were also enrolled in t…
GM-CSF expression by human lung microvascular endothelial cells: in vitro and in vivo findings.
2002
Recently, many findings indicate that granulocyte-macrophage colony-stimulating factor (GM-CSF) plays an important role in the pathogenesis of acute and chronic lung diseases. In the present paper, the production of this cytokine in human pulmonary microvascular endothelial cells (HPMEC) is investigated. In an in vitro study, quiescent HPMEC did not express GM-CSF, either at the transcriptional or at the protein level. After activation for 4 h with tumor necrosis factor (TNF)-α (30/300 U/ml), lipopolysaccharide (LPS; 0.1/1 μg/ml), or interleukin (IL)-1β (100 U/ml), a significant release of GM-CSF was measured by enzyme-linked immunosorbent assay, with a time-dependent increase over 72 h. IL…
Observation of ventilation-induced Spo(2) oscillations in pigs: first step to noninvasive detection of cyclic recruitment of atelectasis?
2010
High arterial partial oxygen pressure (Pao(2)) oscillations within the respiratory cycle were described recently in experimental acute lung injury. This phenomenon has been related to cyclic recruitment of atelectasis and varying pulmonary shunt fractions. Noninvasive detection of Spo(2) (oxygen saturation measured by pulse oximetry) as an indicator of cyclic collapse of atelectasis, instead of recording Pao(2) oscillations, could be of clinical interest in critical care. Spo(2) oscillations were recorded continuously in three different cases of lung damage to demonstrate the technical feasibility of this approach. To deduce Pao(2) from Spo(2), a mathematical model of the hemoglobin dissoci…
The murine bronchopulmonary microcirculation in hapten-induced inflammation
2006
ObjectiveThe clinical observation of central bronchial artery hypertrophy in chronic lung inflammation suggests the possibility that the bronchial circulation may also participate in adaptive responses in peripheral lung inflammation.MethodsTo investigate the potential role of the bronchial microcirculation in peripheral lung inflammation, we developed a murine model of lung inflammation using the intratracheal instillation of the peptide-hapten trinitrophenol in presensitized mice.ResultsClinical parameters indicated a peak inflammatory response at 96 hours. Similarly, gross and microscopic evidence of inflammation was observed 96 hours after antigen instillation. Using a forced oscillatio…
Fetal programming and its effects on vascular pulmonary circulation
2018
Into the scientific community, consensus about the emerging concept of “the fetal origin of adult diseases” is growing. It sustains that the parental (of the two parents) adversities, and the related external influences, during the intra-utero/ perinatal life of each eutherian mammal organism, human included, can permanently set the structure and functionality of specific body systems (i.e., immune, endocrine, nervous and cardiovascular systems), predisposing them to early ageing and disease during adulthood. The pulmonary circulation system also appears to be one of its targets. Established evidence supports the strong association between developmental programming and pulmonary arterial re…