Hemodynamic and oxygen transport effects of dopamine and dobutamine were studied in a series of 25 critically ill postoperative general surgical patients by a prospective, randomized crossover design after maximal response to fluids had been obtained. Dopamine increased MAP, HR, CI, PvO2, DO2, and Qsp while decreasing PaO2. Dobutamine increased HR, CI, SI, stroke work, DO2, VO2, and Qsp while decreasing PAWP and SVRI and PVRI. In general, the effects of the two drugs were greater in patients in the first 72 hours after surgery. The effects of dobutamine on flow and oxygen transport were greater than those of dopamine, especially in the early postoperative period. The effects were smaller and not significant in patients more than three days after surgery, as well as in those with sepsis, respiratory failure, renal failure, age over 65 years, and hyperdynamic states, in part because of the small number of patients in each group. These data are consistent with the hypothesis that the beta 2-adrenergic action of dobutamine vasodilates the previously constricted peripheral circulation, enhances tissue perfusion by improving micro-circulatory flow distribution, and improves DO2 and VO2.
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http://dx.doi.org/10.1378/chest.96.1.120 | DOI Listing |
PLoS Biol
January 2025
School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America.
Oxygen availability is a key factor in the evolution of multicellularity, as larger and more sophisticated organisms often require mechanisms allowing efficient oxygen delivery to their tissues. One such mechanism is the presence of oxygen-binding proteins, such as globins and hemerythrins, which arose in the ancestor of bilaterian animals. Despite their importance, the precise mechanisms by which oxygen-binding proteins influenced the early stages of multicellular evolution under varying environmental oxygen levels are not yet clear.
View Article and Find Full Text PDFJ Lipid Res
January 2025
Physiology and Pathophysiology of Cells and Membranes, Medical School OWL, Bielefeld University, Bielefeld, Germany. Electronic address:
The environmental pollutant cadmium (Cd) poses a threat to human health through consumption of contaminated foodstuffs culminating in chronic nephrotoxicity. Mitochondrial dysfunction and excessive reactive oxygen species (ROS) are key to Cd cellular toxicity. Cd-lipid interactions have been less considered.
View Article and Find Full Text PDFJ Environ Manage
January 2025
Department of Environmental Engineering, Korea National University of Transportation, Chungju, 27469, Republic of Korea. Electronic address:
This study investigates the use of nano-sized oxygen bubbles (NOBs) to enhance BTEX (benzene, toluene, ethylbenzene, xylene) biodegradation in groundwater. Optimized NOBs, averaging 155 nm and at a concentration of 6.59 × 10⁸ bubbles/mL, were found to provide sustained oxygen release with a half-life of approximately 50 days.
View Article and Find Full Text PDFFree Radic Res
January 2025
Department of Human and Animal Physiology, Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, Russia.
Reactive oxygen species (ROS) produced by NADPH oxidase promote contraction of peripheral arteries, which is especially pronounced in early postnatal period in comparison to adulthood, but the mechanisms of such vasomotor influence are poorly understood. We tested the hypothesis that Rho-kinase and protein kinase C (PKC) mediate procontractile influence of NADPH oxidase derived ROS in peripheral artery of early postnatal rats. In addition, we evaluated the involvement Src-kinase and L-type voltage-gated Ca channels (LTCC) into procontractile influence of ROS, produced by NADPH oxidase, because of their known interplay with Rho-kinase and PKC pathways.
View Article and Find Full Text PDFJ Chem Phys
January 2025
Department of Chemical Engineering, Indian Institute of Science, Bengaluru, Karnataka 560012, India.
Heteropolar two-dimensional materials, including hexagonal boron nitride (hBN), are promising candidates for seawater desalination and osmotic power harvesting, but previous simulation studies have considered bare, unterminated nanopores in molecular dynamics (MD) simulations. There is presently a lack of force fields to describe functionalized nanoporous hBN in aqueous media. To address this gap, we conduct density functional theory (DFT)-based ab initio MD simulations of hBN nanopores surrounded by water molecules.
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