Search results for "circulatory and respiratory physiology"
showing 10 items of 329 documents
Evidence for a relationship between mitochondrial Complex I activity and mitochondrial aldehyde dehydrogenase during nitroglycerin tolerance: effects…
2012
The medical use of nitroglycerin (GTN) is limited by patient tolerance. The present study evaluated the role of mitochondrial Complex I in GIN biotransformation and the therapeutic effect of mitochondrial antioxidants. The development of GIN tolerance (in rat and human vessels) produced a decrease in mitochondrial 02 consumption. Co-incubation with the mitochondria-targeted antioxidant mitoquinone (MQ 10(-6) mol/L) or with glutathione ester (GEE, 10(-4) mol/L) blocked GTN tolerance and the effects of GTN on mitochondrial respiration and aldehyde dehydrogenase 2 (ALDH-2) activity. Biotransformation of GTN depended on the mitochondria being functionally active, particularly mitochondrial Comp…
Nitroglycerine causes mitochondrial reactive oxygen species production: In vitro mechanistic insights
2007
Background Nitroglycerine (GTN) is an organic nitrate that has been used for more than 100 years. Despite its widespread clinical use, several aspects of the pharmacology of GTN remain elusive. In a recent study, the authors of the present study showed that GTN causes opening of the mitochondrial permeability transition pore (mPTP) and mitochondrial production of reactive oxygen species (ROS). Objective In the present study, it was tested whether GTN-induced ROS production depends on mitochondrial potassium ATP-dependent channel or mPTP opening, and/or GTN biotransformation. Methods and results Isolated rat heart mitochondria were incubated with succinate (a substrate for complex II) and GT…
MyRIP, a novel Rab effector, enables myosin VIIa recruitment to retinal melanosomes
2002
Defects of the myosin VIIa motor protein cause deafness and retinal anomalies in humans and mice. We report on the identification of a novel myosin-VIIa-interacting protein that we have named MyRIP (myosin-VIIa- and Rab-interacting protein), since it also binds to Rab27A in a GTP-dependent manner. In the retinal pigment epithelium cells, MyRIP, myosin VIIa and Rab27A are associated with melanosomes. In transfected PC12 cells, overexpression of MyRIP was shown to interfere with the myosin VIIa tail localization. We propose that a molecular complex composed of Rab27A, MyRIP and myosin VIIa bridges retinal melanosomes to the actin cytoskeleton and thereby mediates the local trafficking of thes…
Contrast-Enhanced Magnetic Resonance Angiography of the Pulmonary Vasculature
1998
Magnetic resonance angiography (MRA) has been established as a powerful noninvasive imaging modality. Its applications to the study of the pulmonary vasculature have been hampered by a multitude of factors, such as respiratory and cardiac motion artifacts, saturation problems, long acquisition times
Seawater carbonate chemistry and carbon sources of mussel shell carbonate
2018
Ocean acidification and warming is widely reported to affect the ability of marine bivalves to calcify, but little is known about the underlying mechanisms. In particular, the response of their calcifying fluid carbonate chemistry to changing seawater carbonate chemistry remains poorly understood. The present study deciphers sources of the dissolved inorganic carbon (DIC) in the calcifying fluid of the blue mussel (Mytilus edulis) reared at two pH (8.1 and 7.7) and temperature (16 and 22 °C) levels for five weeks. Stable carbon isotopic ratios of seawater DIC, mussel soft tissues and shells were measured to determine the relative contribution of seawater DIC and metabolically generated carb…
"Table 8" of "Measurement of the cross section for W-boson production in association with jets in ppbar collisions at s**(1/2) = 1.96-TeV"
2008
Total cross sections for W production in association with 3 or more jets.
Angiotensin II, type 2 receptor in the development of vesico-ureteric reflux
2001
Objective To investigate if mutation of the angiotensin II (Ang II) receptors AT2 is involved in primary vesico-ureteric reflux (VUR) in humans. Patients and methods Genetic polymorphisms in the AT1 and AT2 receptors was evaluated in 23 patients having the most common congenital urological abnormality, namely primary congenital VUR. The occurrence of the A1166C transition in the AT1 receptor gene and the A-1332G transition in the AT2 receptor gene were evaluated and compared with the incidence in normal controls with no urological abnormalities. Result The distribution of the AT1 receptor genotypes was no different between patients with VUR and healthy controls. Furthermore, 10 of 23 (44%) …
2021 European Thyroid Association Guidelines for the Management of Iodine-Based Contrast Media-Induced Thyroid Dysfunction
2021
Given the fact that a large number of radiological examinations using iodine-based contrast media (ICM) are performed in everyday practice, clinicians should be aware of potential ICM-induced thyroid dysfunction (TD). ICM can induce hyperthyroidism (Hyper) or hypothyroidism (Hypo) due to supraphysiological concentrations of iodine in the contrast solution. The prevalence of ICM-induced TD varies from 1 to 15%. ICM-induced Hyper is predominantly found in regions with iodine deficiency and in patients with underlying nodular goiter or latent Graves’ disease. Patients at risk for ICM-induced Hypo include those with autoimmune thyroiditis, living in areas with sufficient iodine supply. Most cas…
A pilot study demonstrating how inhaled furosemide enhances the bronchodilator effect of salbutamol
1993
Abstract To investigate whether inhaled furosemide can improve the bronchodilator effect of salbutamol, a single-blind crossover study in 10 subjects with stable asthma was designed. Each subject inhaled two puffs of salbutamol (200 μg) 1 hour after premedication with an aerosol preparation of either furosemide or placebo. Forced expiratory volume in 1 second (FEV 1 ) was measured before premedication, again before inhalation of salbutamol, and again 30, 60, and 90 minutes after, and 2, 3, 4, and 5 hours after inhalation of salbutamol. The FEV 1 at each time interval was greater on furosemide days but the difference was significant at 1, 4, and 5 hours after salbutamol inhalation. The areas…
Über die Wirkung von Prostaglandin E1 auf den Ca-Haushalt isolierter Meerschweinchenherzen
1967
The stimulatory effect of PGE1 on different functions of isolated guinea-pig hearts (Langendorff method, Tyrode solution) was coupled with an increase in the rate of45Ca uptake from the perfusion medium. The total myocardial Ca content and the amount of exchangeable cellular Ca were not affected. This action of PGE1 on the myocardial Ca metabolism seems to be related to the positive inotropic action of PGE1 and can most probably be explained by an increase in the membrane permeability to Ca ions (similar to the action of epinephrine).