Damage to Mitochondrial Complex I During Cardiac Ischemia Reperfusion Injury is Reduced Indirectly by Anti-anginal Drug Ranolazine

Ranolazine, an anti-anginal drug, is a late Na+ channel current blocker that is also believed to attenuate fatty acid oxidation and mitochondrial respiratory complex I activity, especially during ischemia. In this study, we investigated if ranolazine\u27s protective effect against cardiac ischemia/reperfusion (IR) injury is mediated at the mitochondrial level and specifically if respiratory complex I (NADH Ubiquinone oxidoreductase) function is protected. We treated isolated and perfused guinea pig hearts with ranolazine just before 30 min ischemia and then isolated cardiac mitochondria at the end of 30 min ischemia and/or 30 min ischemia followed by 10 min reperfusion. We utilized spectrophotometric and histochemical techniques to assay complex I activity, Western blot analysis for complex I subunit NDUFA9, electron paramagnetic resonance for activity of complex I Fe–S clusters, enzyme linked immuno sorbent assay (ELISA) for determination of protein acetylation, native gel histochemical staining for respiratory supercomplex assemblies, and high pressure liquid chromatography for cardiolipin integrity; cardiac function was measured during IR. Ranolazine treated hearts showed higher complex I activity and greater detectable complex I protein levels compared to untreated IR hearts. Ranolazine treatment also led to more normalized electron transfer via Fe–S centers, supercomplex assembly and cardiolipin integrity. These improvements in complex I structure and function with ranolazine were associated with improved cardiac function after IR. However, these protective effects of ranolazine are not mediated by a direct action on mitochondria, but rather indirectly via cytosolic mechanisms that lead to less oxidation and better structural integrity of complex I

Performance characteristics of eight estradiol immunoassays

Journal ArticleMeasurement of estradiol is useful in assisted reproduction, evaluation of infertility, menopause, and male feminization. The analytic performance of 8 estradiol immunoassays was evaluated. The imprecision and accuracy of the Access, ADVIA Centaur, ARCHITECT i2000, AutoDELFIA, Elecsys 2010, IMMULITE 2000, and Vitros ECi estradiol assays (see text for proprietary information) were evaluated by using an isotope dilution-gas chromatography-mass spectrometry (ID-GC-MS) reference method. The coefficient of variation (CV) ranged from 6.9% on the Elecsys 2010 to 42.6% on the ADVIA Centaur at an estradiol concentration of 18 pg/mL (66 pmol/L), with the ARCHITECT i2000 assay in development and the Vitros ECi having a CV below 10% at this estradiol concentration. Agreement between the automated assays and ID-GC-MS was variable, with slopes ranging from 0.87 to 1.20. The Access, ARCHITECT i2000 in development, and the IMMULITE 2000 were the most accurate, with slopes of 0.99, 0.98, and 1.03, respectively. These findings indicate that the ARCHITECT i2000 estradiol assay in development had the best precision and accuracy of the assays evaluated for measurement of serum estradiol concentrations

Phase-resolved NuSTAR and Swift-XRT Observations of Magnetar 4U 0142+61

We present temporal and spectral analysis of simultaneous 0.5-79 keV Swift-XRT and NuSTAR observations of the magnetar 4U 0142+61. The pulse profile changes significantly with photon energy between 3 and 35 keV. The pulse fraction increases with energy, reaching a value of ~20%, similar to that observed in 1E 1841-045 and much lower than the ~80% pulse fraction observed in 1E 2259+586. We do not detect the 55-ks phase modulation reported in previous Suzaku-HXD observations. The phase-averaged spectrum of 4U 0142+61 above 20 keV is dominated by a hard power law with a photon index, $\Gamma$ ~ 0.65, and the spectrum below 20 keV can be described by two blackbodies, a blackbody plus a soft power law, or by a Comptonized blackbody model. We study the full phase-resolved spectra using the electron-positron outflow model of Beloborodov (2013). Our results are consistent with the parameters of the active j-bundle derived from INTEGRAL data by Hascoet et al. (2014). We find that a significant degeneracy appears in the inferred parameters if the footprint of the j-bundle is allowed to be a thin ring instead of a polar cap. The degeneracy is reduced when the footprint is required to be the hot spot inferred from the soft X-ray data.Comment: 14 pages, 8 figures, 4 tables. Accepted for publication in Ap

Kinetic-inductance-limited reset time of superconducting nanowire photon counters

We investigate the recovery of superconducting NbN-nanowire photon counters after detection of an optical pulse at a wavelength of 1550 nm, and present a model that quantitatively accounts for our observations. The reset time is found to be limited by the large kinetic inductance of these nanowires, which forces a tradeoff between counting rate and either detection efficiency or active area. Devices of usable size and high detection efficiency are found to have reset times orders of magnitude longer than their intrinsic photoresponse time.Comment: Submitted to Applied Physics Letter

Commentary on "Correlation of solubility of hexamethylene-1,6-bisthiosulphate disodium salt dihydrate versus dielectric constants of water + ethanol mixtures"

This article discusses the finding that Apelblat model equation coefficients are found to give calculated mole fractions that exceed unity for the solubility of hexamethylene-1,6-bisthiosulphate disodium salt dihydrate dissolved in binary aqueous-ethanol solvent mixtures

Experimental Drying Characteristics Of Fabrics Under Vacuum

A significant amount of the energy consumed in both residential and commercial sectors is used for clothes drying. In conventional convective clothes drying, hot dry air at atmospheric pressure is passed over and through the clothes in order to remove moisture. Both the heat and water carried out are wasted to ambient resulting in an inefficient process. Additionally, the elevated drying temperatures can damage the fibers of the clothes, reducing their useful lifespan. By drying clothes at pressures below atmospheric, the temperature required to drive out moisture can be reduced. The objective of this study is to investigate the drying behavior of different fabrics under sub-atmospheric conditions. A special apparatus is designed and used for this study with appropriate control on the pressure and contact surface temperature. A wet cloth is placed on a heated plate within a vacuum chamber. The mass of the cloth is measured by a balance while the plate’s temperature and the vacuum chamber’s pressure are maintained. Moisture is driven out of the cloth by conduction from the plate. Clothes are dried from approximately 60% to 0% of moisture by mass and curves of moisture percentage versus time are developed for each fabric at set temperatures and pressures. The overall goal of the analysis to establish the drying behavior of clothes under reduced pressure conditions. The resulting data is summarized in form of appropriate performance correlations which can be used for the design of full-scale devices capable of drying under the considered conditions