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Two metal–organic frameworks (MOFs) with different Cu-centered coordination structures were synthesized. By introducing 4,4-bipyridine as a linker in the Cu-MOFs, we have discovered that Cu–O, instead of Cu–N, is the active site with higher electrocatalytical activity towards ascorbic acid, which is essential to understand and develop Cu-based ascorbic acid sensors. [ABSTRACT FROM AUTHOR]

The phytohormone auxin controls many processes in plants, at least in part through its regulation of cell expansion.sup.1. The acid growth hypothesis has been proposed to explain auxin-stimulated cell expansion for five decades, but the mechanism that underlies auxin-induced cell-wall acidification is poorly characterized. Auxin induces the phosphorylation and activation of the plasma membrane H.sup.+-ATPase that pumps protons into the apoplast.sup.2, yet how auxin activates its phosphorylation remains unclear. Here we show that the transmembrane kinase (TMK) auxin-signalling proteins interact with plasma membrane H.sup.+-ATPases, inducing their phosphorylation, and thereby promoting cell-wall acidification and hypocotyl cell elongation in Arabidopsis. Auxin induced interactions between TMKs and H.sup.+-ATPases in the plasma membrane within seconds, as well as TMK-dependent phosphorylation of the penultimate threonine residue on the H+-ATPases. Our genetic, biochemical and molecular evidence demonstrates that TMKs directly phosphorylate plasma membrane H.sup.+-ATPase and are required for auxin-induced H.sup.+-ATPase activation, apoplastic acidification and cell expansion. Thus, our findings reveal a crucial connection between auxin and plasma membrane H.sup.+-ATPase activation in regulating apoplastic pH changes and cell expansion through TMK-based cell surface auxin signalling. Auxin induces transmembrane-kinase-dependent activation of H.sup.+-ATPase in the plasma membrane through phosphorylation of its penultimate threonine residue, promoting apoplastic acidification and hypocotyl cell elongation in Arabidopsis., Author(s): Wenwei Lin [sup.1] [sup.2] , Xiang Zhou [sup.1] [sup.2] , Wenxin Tang [sup.1] , Koji Takahashi [sup.3] [sup.4] , Xue Pan [sup.2] , Jiawei Dai [sup.1] , Hong Ren [...]

Background: Androgenetic alopecia (AGA) causes thinning hair, but poor hair quality in balding areas and damage from UV radiation have been overlooked. Plant extracts like Platycladus orientalis flavonoids (POFs) may improve hair quality in AGA. This study examines POFs' effectiveness in treating AGA-affected hair and repairing UV-induced damage. Methods: Hair samples were analyzed using scanning electron microscopy (SEM) to examine surface characteristics, electron paramagnetic resonance (EPR) spectroscopy to measure free radicals in the hair, and spectrophotometry to assess changes in hair properties. Results: POFs effectively removed hydroxyl radicals from keratinocytes and had antioxidant properties. They also reduced UV-induced damage to AGA hair by mitigating the production of melanin free radicals. Following POF treatment, the reduction in peroxidized lipid loss in AGA hair was notable at 59.72%, thereby effectively delaying the progression of hair color change. Moreover, protein loss decreased by 191.1 μ/g and tryptophan loss by 15.03%, ultimately enhancing hair's tensile strength. Conclusion: compared to healthy hair, hair damaged by AGA shows more pronounced signs of damage when exposed to UV radiation. POFs help protect balding hair by reducing oxidative damage and slowing down melanin degradation. [ABSTRACT FROM AUTHOR]

Herein, we report a cyanation and hydrolysis cascade of aryl bromides with CuCN under noble-metal-free conditions, giving a series of primary amides in moderate to excellent yields (Scheme 1d). In these cases, aryl primary amides are generally synthesized from aryl halides and the gases carbon monoxide (CO) and ammonia (NH SB 3 sb ). Keywords: primary amides; aryl bromides; copper(I) cyanide; copper catalysis; one-pot reaction; late-stage modification EN primary amides aryl bromides copper(I) cyanide copper catalysis one-pot reaction late-stage modification 1991 1996 6 10/09/23 20231024 NES 231024 Graph Primary amides are valuable synthetic intermediates in organic chemistry, and are widely present in lubricants, detergents, drugs, and pesticides. Primary amides, aryl bromides, copper(I) cyanide, copper catalysis, one-pot reaction, late-stage modification. [Extracted from the article]