24 research outputs found
Prospects for Creation of Cardioprotective and Antiarrhythmic Drugs Based on Opioid Receptor Agonists
It has now been demonstrated that the μ, δ(1), δ(2), and κ(1) opioid receptor (OR) agonists represent the most promising group of opioids for the creation of drugs enhancing cardiac tolerance to the detrimental effects of ischemia/reperfusion (I/R). Opioids are able to prevent necrosis and apoptosis of cardiomyocytes during I/R and improve cardiac contractility in the reperfusion period. The OR agonists exert an infarct‐reducing effect with prophylactic administration and prevent reperfusion‐induced cardiomyocyte death when ischemic injury of heart has already occurred; that is, opioids can mimic preconditioning and postconditioning phenomena. Furthermore, opioids are also effective in preventing ischemia‐induced arrhythmias
Recommended from our members
Argonne National Laboratory Reports
Working fluids used in Rankine bottoming cycle systems for heat recovery from long-haul trucks, marine vessels, and railroad locomotives are examined. Rankine bottoming cycle systems improve fuel economy by converting the exhaust heat from the prime mover into useful power. The report assesses fluid property requirements on the basis of previous experience with bottoming cycle systems. Also, the exhaust gas characteristics for the transportation modes of interest are summarized and compared. Candidate working fluids are discussed with respect to their potential for use in Rankine bottoming cycle systems. Analytical techniques are presented for calculating the thermodynamic properties of single-component working fluids. The resulting equations have been incorporated into a computer code for predicting the performance of Rankine bottoming cycle systems. In evaluating candidate working fluids, the code requires the user to input only a minimal amount of fluid property data
Determination of Thermal-Degradation Rates of Some Candidate Rankine-Cycle Organic Working Fluids for Conversion of Industrial Waste Heat Into Power
Serious concerns over the long-term thermal stability of organic working fluids and its effect on system performance, reliability, and overall economics have impeded widespread development and deployment of organic Rankine-cycle power systems (ORCPSs) for conversion of industrial waste heat into power. Prototype systems built using thermal stability information derived from static capsule tests have often operated less than satisfactorily. This investigation is an attempt by the U.S. Department of Energy (DOE) to alleviate these fears, dissipate the remaining road blocks, and accelerate the further development and deployment of this vital industrial energy-conservation technology. This paper presents some interim results of an experimental investigation undertaken
determine degradation rates (as a function of maximum cycle temperature) of four organic working fluids considered potential candidates for use in a Rankine-cycle power-conversion system. The four fluids under investigation are Fluorinol 85, 2methylpyridine/water, toluene, and Freon R-113
Reduced radiation dose and improved image quality at cardiovascular CT angiography by automated attenuation-based tube voltage selection: intra-individual comparison.
To evaluate the effect of automated tube voltage selection on radiation dose and image quality at cardiovascular CT angiography (CTA).We retrospectively analysed paired studies in 72 patients (41 male, 60.5 ± 16.5 years), who had undergone CTA acquisitions of the heart or aorta both before and after the implementation of an automated x-ray tube voltage selection algorithm (ATVS). All other parameters were kept identical between the two acquisitions. Subjective image quality (IQ) was rated and objective IQ was measured by image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and figure of merit (FOM). Image quality parameters and effective dose were compared between acquisitions.Overall subjective image quality improved with the percentage of cases scored as adequate or higher increasing from 79 \% to 92 \% after implementation of ATVS (P = 0.03). SNR (14.1 ± 5.9, 15.7 ± 6.1, P = 0.009), CNR (11.6 ± 5.3, 13.2 ± 5.6, P = 0.011), and FOM (19.9 ± 23.3, 43.8 ± 51.1, P < 0.001) were significantly higher after implementation of ATVS. Mean image noise (24.1 ± 8.4 HU, 22.7 ± 7.1 HU, P = 0.048) and mean effective dose (10.6 ± 5.9 mSv, 8.8 ± 5.0 mSv, P = 0.003) were significantly lower after implementation of ATVS.Automated tube voltage selection can operator-independently optimize cardiovascular CTA image acquisition parameters with improved image quality at reduced dose.• Automatic tube voltage selection optimizes tube voltage for each individual patient. • In this population, overall radiation dose decreased while image quality improved. • This tool may become valuable for improving dose/quality ratio