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A supramolecular polymer was constructed from a light‐driven overcrowded alkene switch modified with two alkylated gallic acid amide pendants (MSP‐1). Upon UV irradiation, stable MSP‐1 isomerized into unstable MSP‐2, which induced the effective collapse of well‐defined cross‐linked supramolecular polymers, and the reassembly can be realized by aging at low temperature. [ABSTRACT FROM AUTHOR]

Lichtgetrieben: Wasserlösliche Poly(acrylsäure) ‐ Katalysatoren PAA ‐ g ‐ Fe2S2 mit biomimetischen {Fe2S2} ‐ Zentren wurden hergestellt. Zusammen mit CdSe ‐ Quantenpunkten (CdSe ‐ QDs) und Ascorbinsäure zeigen sie außergewöhnliche Turnoverzahlen (TON) und ‐ frequenzen (TOF) von 27 135 bzw. 3.6 s−1 für die photokatalytische Bildung von H2 in Wasser; dies ist die bisher höchste Effizienz für [FeFe] ‐ Hydrogenasemimetika. [ABSTRACT FROM AUTHOR]

Aims: Aspirin has been used for the secondary prevention and treatment of cardiovascular disease for several decades. We investigated the roles of transcriptional factor activator protein 2α (AP-2α) in the beneficial effects of aspirin in the growth and vulnerability of atherosclerotic plaque., Methods and Results: In mice deficient of apolipoprotein E (Apoe-/-), aspirin (20, 50 mg/kg/day) suppressed the progression of atherosclerosis in aortic roots and increased the plaque stability in carotid atherosclerotic plaques induced by collar-placement. In vivo lentivirus-mediated RNA interference of AP-2α reversed the inhibitory effects of aspirin on atherosclerosis in Apoe-/- mice. Mechanically, aspirin increased AP-2α phosphorylation and its activity, upregulated IkBα mRNA and protein levels, and reduced oxidative stress in cultured vascular smooth muscle cells. Furthermore, deficiency of AP-2α completely abolished aspirin-induced upregulation of IkBα levels and inhibition of oxidative stress in Apoe-/- mice. Clinically, conventional doses of aspirin increased AP-2α phosphorylation and IkBα protein expression in humans subjects., Conclusion: Aspirin activates AP-2α to upregulate IkBα gene expression, resulting in attenuations of plaque development and instability in atherosclerosis., Competing Interests: There is no conflict of interest.

Nature uses hydrogenase enzyme to catalyze proton reduction at pH 7 with overpotentials and catalytic efficiencies that rival platinum electrodes. Over the past several years, [FeFe]-hydrogenase ([FeFe]-H2 ase) mimics have been demonstrated to be effective catalysts for light-driven H2 evolution. However, it remains a significant challenge to realize H2 production by such an artificial photosynthetic system in neutral aqueous solution. Herein, we report a new system for photocatalytic H2 evolution working in a broad pH range, especially under neutral conditions. This unique system is consisted of branched polyethylenimine (PEI)-grafted [FeFe]-H2 ase mimic (PEI-g-Fe2 S2 ), MPA-CdSe quantum dots (MPA=mercaptopropionic acid), and ascorbic acid (H2 A) in water. Due to the secondary coordination sphere of PEI, which has high buffering capacity and stabilizing ability, the system is able to produce H2 under visible-light irradiation with turnover number of 10 600 based on the Fe2 S2 active site in PEI-g-Fe2 S2 . The stability and activity are much better than that of the same system under acidic or basic conditions and they are, to the best of our knowledge, the highest known to date for photocatalytic H2 evolution from a [FeFe]-H2 ase mimic in neutral aqueous solution., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: To study the chemical constituents of Bidens pilosa var. radiata., Methods: The constituents were separated and purified with silica gel column, and identified by physicochemical properties and spectral methods., Results: Ten compounds were separated and identified as friedelin (1), n-tridecane (2), friedelinol (3), beta-sitosterol (4), 21 a-hydroxyfriedelan-3-one (5), stigmasterol (6), lupeol (7), stigmasterol-3-O-beta-D-glucopyranoside (8), eleosanole acid (9), friedelin-3beta-ol-27-oic acid (10)., Conclusion: Ten compounds are isolated from this plant for the first time.