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Polyurea-based synthetic glycopolymerscontaining sulfated glucose,mannose, glucosamine, or lactose as pendant groups have been synthesizedby step-growth polymerization of hexamethylene diisocyanate and correspondingsecondary diamines. The obtained polymers were characterized by gelpermeation chromatography, nuclear magnetic resonance spectroscopy,and Fourier transform infrared spectroscopy. The nonsulfated polymersshowed similar results to the commercially available biomaterial polyurethaneTECOFLEX in a platelet adhesion assay. The average degree of sulfationafter reaction with SO3was calculated from elemental analysisand found to be between three and four −OSO3groupsper saccharide. The blood-compatibility of the synthetic polymerswas measured using activated partial thromboplastin time, prothrombintime, thrombin time, anti-IIa, and anti-Xa assays. Activated partialthromboplastin time, prothrombin time, and thrombin time results indicatedthat the mannose and lactose based polymers had the highest anticoagulantactivities among all the sulfated polymers. The mechanism of actionof the polymers appears to be mediated via an anti-IIa pathway ratherthan an anti-Xa pathway. [ABSTRACT FROM AUTHOR]

Understanding the presence and dynamics of chemical pollutants in individual cells is fundamentally important for their trafficking, fate, and toxicity in humans. The presence of molecular components (i.e., proteins and mRNA) in individual cells of higher organisms is considered a stochastic event. The characteristics of chemical pollutants, as extrinsic compounds, in subpopulation of human cells on single-cell basis have not been explored yet. Here, we demonstrated the lead (Pb) content in individual mature erythrocytes (m-erythrocytes) of Pb-intoxicated patients, and healthy subjects exhibited a unified pattern in probability distribution (gamma distribution) and dynamics, despite being highly heterogeneous. The Pb content in individual m-erythrocytes decreased with the lifetime of m-erythrocytes. Meanwhile, the distribution and dynamics were found to be highly related to the Pb content in m-erythrocytes and was independent of patients and their status. This is the first study to analyze the distribution pattern of chemical pollutants at a single-cell level in higher organisms. This study sheds light on the molecular mechanism of Pb trafficking and fate in humans and the search for an efficient strategy to improve Pb excretion during Pb treatment.

A series of scarce tetrahydropyridinofullerenes were synthesized by the metal-free-mediated reaction of [60]fullerene with cheap and easily available α-methyl-substituted arylmethanamines and aldehydes in the presence of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and 4-dimethylaminopyridine (DMAP) in moderate to good yields comparable to the previously reported data for most monoadducts. The in situ generation of azadienes played a crucial role in the successful synthesis of tetrahydropyridinofullerenes. A plausible reaction mechanism was proposed to elucidate the reaction process.

The smaller particle sizes, better dispersion, and more heterojunction interfaces can enhance the photocatalytic performance of photocatalysts. Herein, ultradispersed amorphous silver silicates/ultrathin g-C 3 N 4 nanosheets heterojunction composites (a-AgSiO/CNNS) with intimate interfacial coupling effect were synthesized through the facile in situ precipitation of ultrafine a-AgSiO (∼5.2 nm) uniformly dispersed on the entire surface of hierarchical ultrathin CNNS. In this process, the ultrathin CNNS not only perform as the support to form heterostructures but also are employed as dispersant to confine the aggregation of a-AgSiO nanoparticles. Notably, the optimum photocatalytic activity of a-AgSiO/CNNS-500 composite is ∼36 and 13 times higher than that of CNNS toward the degradation of rhodamine B and tetracycline, respectively. The excellent photocatalytic activity can be attributed to the synergistic interactions of heterojunction with strong interfacial coupling effect, improved visible light absorbance, abundant heterojunction interfaces, and fully exposed reactive sites, which originate from the well-defined nanostructures such as uniform packing of the ultrasmall a-AgSiO, the intimate and maximum coupling interfaces between a-AgSiO and CNNS. We believe that such an easy and scalable synthetic strategy can be further extended to the fabrication of other ultrafine semiconductors coupled with g-C 3 N 4 for increasing its photocatalytic performance.

A novel efficient Ag@AgCl/g-C3N4 plasmonic photocatalyst was synthesized by a rational in situ ion exchange approach between exfoliated g-C3N4 nanosheets with porous 2D morphology and AgNO3. The as-prepared Ag@AgCl-9/g-C3N4 plasmonic photocatalyst exhibited excellent photocatalytic performance under visible light irradiation for rhodamine B degradation with a rate constant of 0.1954 min(-1), which is ∼41.6 and ∼16.8 times higher than those of the g-C3N4 (∼0.0047 min(-1)) and Ag/AgCl (∼0.0116 min(-1)), respectively. The degradation of methylene blue, methyl orange, and colorless phenol further confirmed the broad spectrum photocatalytic degradation abilities of Ag@AgCl-9/g-C3N4. These results suggested that an integration of the synergetic effect of suitable size plasmonic Ag@AgCl and strong coupling effect between the Ag@AgCl nanoparticles and the exfoliated porous g-C3N4 nanosheets was superior for visible-light-responsive and fast separation of photogenerated electron-hole pairs, thus significantly improving the photocatalytic efficiency. This work may provide a novel concept for the rational design of stable and high performance g-C3N4-based plasmonic photocatalysts for unique photochemical reaction.