The loose-patch-clamp technique was used on intact cardiac papillary muscle of the rat to examine whether the fast sodium inward current (INa+) is influenced by the beta-adrenergic stimulant isoproterenol (ISO) or by 8-bromo-3',5'-cyclic adenosine monophosphate (8-Br-cAMP), respectively. The amplitude of INa+ evoked by test pulses of 5 ms to a transmembrane potential of 0 mV and its time to peak were analyzed. The availability of INa+ was tested with conditioning pulses of 2.5 s to potentials between -130 mV and -50 mV. The potential of half-maximal availability was slightly shifted to more negative values by 1 microM ISO (2.0 mV, n.s.), as well as by 50 microM 8-Br-cAMP (4.0 mV; p less than 0.05). The peak amplitude of INa+ elicited from strongly negative potentials was increased by ISO (18%, n.s.), while 8-Br-cAMP exerted no directional effect. Depolarizing conditioning pulses (-60 mV) decreased INa+ to 13.3% of the maximal attainable current under control conditions, while ISO decreased INa+ to 9.1% of control (p less than 0.1). Corresponding values under the influence of 8-Br-cAMP were 11.4% and 8.3% (p less than 0.05). Moreover, in the presence of ISO there was a significant shortening of the time to peak of INa+ (0.56 ms to 0.50 ms at -80 mV conditioning potential, p less than 0.05) which could not be detected in the presence of 8-Br-cAMP.(ABSTRACT TRUNCATED AT 250 WORDS)
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Nano Lett
January 2025
Department of Applied Physics and Research Institute for Advanced Manufacturing, The Hong Kong Polytechnic University, Hung Hom, Hong Kong 999077, China.
Sodium metal batteries without pre-deposited Na (anode-free) and with a limited amount of Na metal (anode-less) have attracted increasing attention due to their competitive energy density and the high abundance of sodium. However, severe interfacial issues result in poor cycling stability and low Coulombic efficiency. Here, the lightweight interphase layers composed of intermetallic nanoparticles (Sn-Cu and Sn-Ni) are applied to improve Na plating/stripping behaviors.
View Article and Find Full Text PDFNano Lett
January 2025
Shanghai, China State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China.
Metal sulfide electrodes for sodium-ion batteries face trade-offs among high capacity, fast kinetics, and stability. The challenge lies in breaking and restoring metal-sulfur bonds and allowing rapid ionic transport. Here we explore the boundary of conversion- and intercalation-type metal sulfides to develop ideal sodium-ion storage materials.
View Article and Find Full Text PDFJ Community Hosp Intern Med Perspect
January 2025
Critical Care Medicine, Freeman Health System, Joplin, MO, USA.
Acute urine retention is a common urologic emergency that is frequently seen in the Emergency room (ER). Standard treatment includes placing a urinary catheter or a suprapubic catheter with outpatient urologic follow-up. Urine retention can cause complications, such as hyponatremia and post-obstructive diuresis.
View Article and Find Full Text PDFAnalyst
January 2025
Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan.
A paper-based potentiometric sensor integrated with a polymeric hydrogel has been developed for sodium ion (Na) determination in human urine. The construction of an all-solid-state ion selective electrode (s-ISE) and an all-solid-state reference electrode (s-RE) on a photo paper substrate was achieved using an inkjet printing method. For s-ISE fabrication, carbon nanotubes (CNTs) and gold nanoparticles (AuNPs) were printed on the substrate as a nanocomposite solid contact.
View Article and Find Full Text PDFNutrients
January 2025
Division of Human Nutrition and Health, Wageningen University & Research, 6700 AB Wageningen, The Netherlands.
Background: Rapid socio-economic developments confront China with a rising consumption of ultra-processed foods (UPFs) and ultra-processed drinks (UPDs). This study aims to evaluate their potential impact on diet transformation towards sustainability including nutrition, environmental sustainability, and diet-related cost.
Methods: Dietary intake was assessed by 24 h recalls in 27,311 participants (age: 40.
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