Mie University

Physicochem. properties of atomically precise metal clusters can be modulated by incorporating different metal atoms.In this article, successful one-pot synthesis of single Au-atom doped chiral AuAg₂₈ clusters protected by water-soluble N-acetyl-(S)-penicillamine (=S-NAP) is reported.The reduction of Ag and Au ions at 0 °C in the presence of S-NAP and triphenylphosphine (TPP) using tetramethylammonium borohydride (TMAB) is crucial.Importantly, upon doping of an Au atom to the monometallic Ag₂₉ cluster, which improves the cluster stability, the chiroptical activity or maximum anisotropy factor of the bimetallic AuAg₂₈ cluster is enhanced as compared to that of the monometallic species, which can be due to an increase in the rotatory strength that is probably brought about by the increased contribution of optical transition associated with helically-arranged surface shell layers.Such chiroptical behaviors suggest that the Au dopant position in the bimetallic cluster is not fluxional but rigid.Then the present results will help design some heteroatom-doped silver clusters with excellent chiroptical properties.

High salt (HS) intake induces hypertension and cognitive impairment. Preventive strategies include against dietary supplements. Soybean lecithin is a widely used phospholipid supplement. Lysolecithin is important in cell signaling, digestion, and absorption. This study aimed to investigate the effects of lysophosphatidylcholine containing >70% of the total phospholipids (LPC70), on hypertension and cognitive impairment induced in mice by HS intake. Mice were provided with HS solution (2% NaCl in drinking water) with or without LPC70 for 12 weeks. Blood pressure, cognitive function, and inflammatory response of intestine were determined. Hypertension and impaired object recognition memory induced by HS intake were implicated with increased inducible nitric oxide synthase in the small intestine and tau hyperphosphorylation in the prefrontal cortex. LPC70 treatment prevented cognitive impairment by suppressing inducible nitric oxide synthase and tau hyperphosphorylation. LPC70 may be valuable as a functional food component in preventing HS-induced cognitive impairment.