A kinetic model of the citric acid cycle for calculating oxygen consumption from (13)C nuclear magnetic resonance (NMR) multiplet data has been developed. Measured oxygen consumption (MVO(2)) was compared with MVO(2) predicted by the model with (13)C NMR data obtained from rat hearts perfused with glucose and either [2-(13)C]acetate or [3-(13)C]pyruvate. The accuracy of MVO(2) measured from three subsets of NMR data was compared: glutamate C-4 and C-3 resonance areas; the doublet C4D34 (expressed as a fraction of C-4 area); and C-4 and C-3 areas plus several multiplets of C-2, C-3, and C-4. MVO(2) determined by set 2 (C4D34 only) gave the same degree of accuracy as set 3 (complete data); both were superior to set 1 (C-4 and C-3 areas). Analysis of the latter suffers from the correlation between citric acid cycle flux and exchange between alpha-ketoglutarate and glutamate, resulting in greater error in estimating MVO(2). Analysis of C4D34 is less influenced by correlation between parameters, and this single measurement provides the best opportunity for a noninvasive measurement of oxygen consumption.
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http://dx.doi.org/10.1152/ajpendo.1999.277.6.E1111 | DOI Listing |
J Hazard Mater
January 2025
College of Environmental and Safety Engineering, Shenyang University of Chemical Technology, Shenyang 110142, China; Shenyang Key Laboratory of Chemical Pollution Control, Shenyang University of Chemical Technology, Shenyang 110142, China. Electronic address:
Here, a quenching strategy was developed to create oxygen vacancies in Cu doped α-MnO. The evolutions of oxygen vacancies were directly followed by means of XRD refinement, EPR and XPS. In combination with DFT calculations and detailed characterizations, evidence is captured that oxygen vacancies not only act as direct sites for the adsorption and activation of gaseous oxygen and toluene, but also accelerate the consumption and replenishment cycle of lattice oxygen species by weakening the strength of metal-oxygen bonds.
View Article and Find Full Text PDFChemosphere
January 2025
Institute of Chemical Engineering Sciences, Foundation for Research and Technology Hellas (FORTH/ICE-HT), 26504, Patras, Greece. Electronic address:
The goal of the present work is to quantify the performance of ozonation as a method for the in situ remediation of soils polluted at varying degree with different types of hydrocarbons, and assess its applicability, in terms of remediation efficiency, cost factors, and environmental impacts. Ozonation tests are conducted on dry soil beds, for three specific cases: sandy soil contaminated with low, moderate and high concentration of a non-aqueous phase liquid (NAPL) consisting of equal concentrations of n-decane, n-dodecane, and n-hexadecane; sandy soil polluted with diesel fuel; oil-drilling cuttings (ODC). The transient changes of the concentration of the total organic carbon (TOC), total petroleum hydrocarbons (TPH), polycyclic aromatic hydrocarbons (PAHs), and soluble chemical oxygen demand (SCOD) in soil and carbon dioxide (CO), carbon monoxide (CO), volatile organic compounds (VOCs), and ozone (O) in exhaust gases are recorded.
View Article and Find Full Text PDFBr J Hosp Med (Lond)
January 2025
Department of Sports Arts, Hebei Sport University, Shijiazhuang, Hebei, China.
A novel exercise protocol for cardiac rehabilitation aerobic (CRA) has been developed by Hebei Sport University, demonstrating efficacy in patients with coronary heart disease (CHD). The objective of this study was to evaluate the impact of CRA on precise cardiac rehabilitation (CR) for CHD patients presenting with stable angina pectoris. The study cohort comprised patients with stable angina who were categorized into three groups: the CRA group (n = 35), the power bicycles (PB) group (n = 34), and the control group (n = 43).
View Article and Find Full Text PDFExp Physiol
January 2025
Burdon Sanderson Cardiac Science Centre, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK.
High cardiac sympathetic drive and release of the sympathetic cotransmitter neuropeptide Y (NPY) are significant features of congestive heart failure (CHF), in which resting venous NPY levels are known to be associated with mortality. However, whether circulating NPY levels increase during exercise in CHF when they are already elevated is controversial. We sought to establish the dynamics of circulating NPY levels in CHF patients treated with contemporary medical therapy and devices in relationship to indices of performance linked to long-term prognosis.
View Article and Find Full Text PDFPharmaceuticals (Basel)
December 2024
Department of Biology, Chungnam National University, Daejeon 34134, Republic of Korea.
Objectives: The present study describes the comparative effect of 24-week supplementation of beeswax alcohol (BWA, Raydel, 0.5% and 1.0%, wt/wt) and coenzyme Q (CoQ, 0.
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