Unlabelled: The concentration-dependent toxic effects of exogenous noradrenaline (NA, CAS 51-41-2) on acute regional myocardial ischemia (MI) was investigated with and without alpha- and beta-adrenoceptor blockade. Electrically-driven rabbit Langendorff-hearts with depleted catecholamine stores were used (reserpin 7.0 mg/kg i.p. 16-24 h before preparation, constant pressure: 70 cm H2O, Tyrode solution, Ca2+ 1.8 mmol/l). Repetitive MI, separated by a reperfusion period of 50 min, was induced by coronary artery branch ligature, and quantitated from epicardial NADH-fluorescence photography. Starting after a reperfusion period of 20 min, hearts were treated with exogenous NA (10(-7), 10(-6) or 10(-5) mol/l). Adrenoceptors were blocked by propranolol (10(-6) mol/l) and phentolamine (10(-6) mol/l). Without adrenoceptor blockers, NA 10(-6) mol/l induced an increase in left ventricular pressure and a reduction in the relative coronary flow. Concomitantly, MI was enhanced. After adrenoceptor blockade, NA 10(-7) or 10(-6) mol/l had no influence on functional parameters. MI was not affected by NA 10(-7) mol/l, but MI was significantly enhanced by NA 10(-6) mol/l. MI enhancement by NA 10(-6) mol/l was completely prevented by superoxide dismutase (30 U/ml). Functional effects of NA 10(-5) mol/l were not completely inhibited by adrenoceptor blockers at the concentrations used, and arrythmias were observed. MI was also enhanced by NA 10(-5) mol/l.
Conclusion: Deleterious effects on MI, that are independent on functional effects, are induced by NA in a micromolar concentration. These direct toxic effects are mediated by superoxide anion radicals. In lower concentrations (10(-7) mol/l), there is no evidence for direct toxic actions of NA independent of functional effects. MI enhancement by NA 10(-5), or 10(-6) mol/l without adrenoceptor blockers may have been caused in part by functional and arrythmogenic effects and/or through the generation of oxygen free radicals.
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Naunyn Schmiedebergs Arch Pharmacol
January 2025
Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, 200083, China.
To investigate the effect of icariin (ICA) on hepatocellular carcinoma (HCC) and its autophagy/apoptosis mechanism in HCC. The anti-HCC mechanism of ICA was investigated using HCC cells treated with 20 µmol/L ICA. Cell viability and proliferation were assessed using CCK-8 and colony formation assays, respectively, while TUNEL staining evaluated anti-apoptotic effects.
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January 2025
Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, Beijing, 100081, China. Electronic address:
Background: Glycholic acid (GCA) can dynamically reflect the process of liver injury, and can be used for early diagnosis and curative effect evaluation of early hepatitis and cirrhosis. The highly sensitive detection of liver injury markers is conducive to a more accurate and effective auxiliary diagnosis of liver diseases. In addition, the low trigger potential helps to avoid more chemical interference and improve the detection sensitivity.
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November 2024
Department of Physiology and Immunology, Faculty of Medicine Osijek, J. J. Strossmayer University of Osijek, J. Huttlera 4, 31000 Osijek, Croatia.
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January 2025
Key Laboratory of Green and Precise Synthetic Chemistry and Applications, Ministry of Education, Anhui Provincial Key Laboratory of Synthetic Chemistry and Applications, College of Chemistry and Materials Science, Huaibei Normal University, Huaibei, Anhui, 235000, PR China. Electronic address:
Luminol-loaded mesoporous carbon nanospheres (MCs@LU) were utilized to develop a highly sensitive electrochemiluminescence (ECL) sensor for the detection of L-cysteine (L-Cys). L-Cys acted as the coreactant of luminol, and the pore confinement effect of mesoporous carbons (MCs) resulted in a robust ECL signal. Upon optimization, a linear correlation between the ECL intensity and L-Cys concentration was observed over the range of 5.
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December 2024
São Carlos Institute of Chemistry, University of São Paulo, Av. João Dagnone, 1100, 13566-590, São Carlos, SP, Brazil. Electronic address:
This study reports the development and implementation of a straightforward, rapid, and cost-effective voltammetric technique for piroxicam (PIR) detection at nanomolar concentrations in biological and environmental samples. The method involved the use of a screen-printed electrode (SPE) enhanced with a combination of Printex L6 carbon (PL6C) and polyaniline-based activated carbon (PAC) on a chitosan film crosslinked with epichlorohydrin (CTS:EPH). The detection was carried out using square-wave adsorptive anodic stripping voltammetry (SWAdASV) in a 0.
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