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Thiolate‐protected gold nanoclusters (AuNCs) have attracted significant attention as nano‐catalysts, revealing a superatomic core and gold‐thiolate staples as distinct structural units. Here, we demonstrate the unprecedented dual catalytic activity of thiolate‐protected [Au25(SR)18]− nanoclusters, involving both photosensitized 1O2 generation by the Au13 superatomic core and catalytic carbon‐carbon bond formation facilitated by Au2(SR)3 staples. This synergistic combination of two different catalytic units enables efficient cross‐dehydrogenative coupling of terminal alkynes and tertiary aliphatic amines to afford propargylamines in high yields of up to 93 %. Mixed‐ligand AuNCs bearing both thiolate and alkynyl ligands revealed the intermediacy of the alkynyl‐exchanged AuNCs toward both photosensitization and C−C bond‐forming catalytic cycles. Density functional theory calculations also supported the intermediacy of the alkynyl‐exchanged AuNCs. Thus, the use of ligand‐protected metal nanoclusters has enabled the development of an exceptional multifunctional catalyst, wherein distinct nanocluster components facilitate cooperative photo‐ and chemo‐catalysis. [ABSTRACT FROM AUTHOR]

This article, published in Angewandte Chemie International Edition, discusses the dual catalysis of gold nanoclusters for photocatalytic cross-dehydrogenative coupling. The researchers, Katsuhiro Isozaki, Masaharu Nakamura, and others, explore the cooperative catalytic properties of the superatomic core and gold-thiolate staples through mechanistic investigations and DFT calculations. The study provides insights into the catalytically active intermediates and their role in the cross-dehydrogenative coupling process. [Extracted from the article]

Context: Oxytocin supplementation improves obstructive sleep apnea (OSA), and animal studies suggest involvement of oxytocin in respiratory control. However, the relationship between endogenous oxytocin signaling and human sleep status remains undetermined., Objective: In this study, we approached the contribution of the intrinsic oxytocin-oxytocin receptor (OXTR) system to OSA by genetic association analysis., Methods: We analyzed the relationship between OXTR gene polymorphisms and sleep parameters using questionnaire data and sleep measurements in 305 Japanese participants. OSA symptoms were assessed in 225 of these individuals., Results: The OXTR rs2254298 A allele was more frequent in those with OSA symptoms than in those without ( P = .0087). Although total scores on the Pittsburgh Sleep Quality Index questionnaire did not differ between the genotypes, breathlessness and snoring symptoms associated with OSA were significantly more frequent in individuals with rs2254298 A genotype ( P = .00045 and P = .0089 for recessive models, respectively) than the G genotype. A multivariable analysis confirmed these genotype-phenotype associations even after adjusting for age, sex, and body mass index in a sensitivity analysis. Furthermore, objective sleep efficiency measured by actigraph was not significantly different between genotypes; however, subjective sleep efficiency was significantly lower in the rs2254298 A genotype ( P = .013) compared with the G genotype. The frequency of the A allele is higher in East Asians, which may contribute to their lean OSA phenotype., Conclusion: The OXTR gene may contribute to OSA symptoms via the respiratory control system, although it could be in linkage disequilibrium with a true causal gene., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society.)

Although the relationship between dyslipidaemia (DL) and coronary artery disease (CAD) or between trace minerals intake and CAD is well known separately, the exact nature of this relationship remains unknown. We hypothesize that the relationship between trace mineral intake and CAD may differ depending on whether or not the individual has DL. The present study analysed the relationships among trace mineral intake, DL, and CAD in middle-aged and older adults living in Shika town, Ishikawa prefecture, Japan. This study included 895 residents following the exclusion of those with genetic risk carriers for familial hypercholesterolemia. Trace mineral intake was evaluated using the brief-type self-administered diet history questionnaire. Interactions were observed between DL and CAD with zinc ( p = 0.004), copper ( p = 0.010), and manganese intake ( p < 0.001) in a two-way analysis of covariance adjusted for covariates such as sex, age, body mass index, and current smokers and drinkers. Multiple logistic regression analysis showed that zinc (odds ratio (OR): 0.752; 95% confidence interval (CI): 0.606, 0.934; p = 0.010), copper (OR: 0.175; 95% CI: 0.042, 0.726; p = 0.016), and manganese (OR: 0.494; 95% CI: 0.291, 0.839; p = 0.009) were significant independent variables for CAD in the dyslipidaemic group. The present results suggest that DL with a low trace mineral intake is associated with CAD. Further longitudinal studies are required to confirm this relationship., Competing Interests: None., (© The Author(s) 2024.)

Exploration of multiple bonds between superatoms remains an uncharted territory. In this study, we present the synthesis and characterization of N 2 -type superatomic molecules featuring triple bonds between two superatoms. The successful synthesis of M 2 Au 17 (M = Pd, Pt) nanoclusters hinged upon the photoinduced fusion of MAu 12 superatoms, achieved through sequential electron transfer and detachment of [AuPR 3 ] + species. Solid-state structures were confirmed via X-ray crystallography, while their electronic structures were elucidated through density functional theory (DFT) calculations. Analysis of electronic absorption properties, coupled with time-dependent DFT calculations, unveiled a symmetry-dependent electron transition nature between superatomic molecular orbitals, akin to that observed in conventional molecules.

Iron oxide nanoparticles (NPs) are nontoxic and abundant materials which have long been investigated as reusable catalysts in oxidation reactions, but their use so far has been hampered by a low selectivity. Here, unsupported iron oxide NPs have been found to successfully catalyze the microwave-assisted oxidation of primary and secondary alcohols to their respective aldehydes and ketones with a high selectivity when N -methylmorpholine N -oxide was used as the terminal oxidant. The crystalline phase and size of the iron-based catalyst have a drastic effect on its activity, with small magnetite (Fe 3 O 4 ) NPs being the optimal catalyst for this reaction. The nanocatalyst could be easily recovered by magnetoseparation and successfully recycled four times without any need for special pretreatment or reactivation step and with a minimal loss of activity. The subsequent loss of activity was attributed to the transition from magnetite (Fe 3 O 4 ) to maghemite (γ-Fe 2 O 3 ), as confirmed by X-ray diffraction, Fourier transform infrared, and X-ray absorption near-edge spectroscopy. The nanocatalyst could then be reactivated by the high-temperature microwave treatment and used again for the microwave-assisted oxidation reaction., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)