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Bone marrow mesenchymal stem cells (BM-MSCs), with the properties of self-renewal and pluripotency, can migrate to the tumor sites and exert complex effects on tumor progression and communications by releasing exosomes. However, to our knowledge, only a few studies have reported the effects of BM-MSCs exosomes on breast cancer cells development. Here, utilizing exosomes isolated from in vitro BM-MSCs, we systematically investigated this issue in a breast cancer cell line. In this study, we found that BM-MSCs exosomes are actively incorporated by breast cancer cell MDA-MB-231 cells and subsequently promote MDA-MB-231 cells proliferation and migration. Mechanistically, we further found Yes-associated protein (YAP) and transcriptional coactivator with PDZ binding motif (TAZ) which are Hippo signaling components were involved in this promoting progress. Consistently, YAP and TAZ knockdown could significantly reverse breast cancer cells proliferation and migration improved by BM-MSCs exosomes. Taken together, our findings demonstrated a new mechanism through which BM-MSCs-derived exosomes may contribute to breast cancer cells proliferation and migration, which might provide an evidence for novel drug discovery based on exosomes and Hippo signaling. [ABSTRACT FROM AUTHOR]

On the catalyst surface, crystal facets with different surface atom arrangements and diverse physicochemical properties lead to distinct catalytic activity. Acquiring a highly reactive facet through surface regulation is an efficient strategy to promote the oxidative decomposition of wastewater organic pollutants via peroxymonosulfate (PMS) activation. However, the mechanism through which crystal facets affect PMS activation is still unclear. In this study, three facet-engineered α-MnO2 with different exposed facets were prepared via a facile hydrothermal route. The prepared 310-MnO2 exhibited superior PMS activation performance to 100-MnO2 and 110-MnO2. Moreover, the 310-MnO2/PMS oxidative system was active over a wide pH range and highly resistant to interfering substances from wastewater. These advantages of the 310-MnO2/PMS system make it highly promising for practical wastewater treatment. Based on quenching experiments, electron paramagnetic resonance (EPR) analysis, solvent exchange, and electrochemical measurements, mediated electron transfer was found to be the dominant nonradical pathway for p-chloroaniline (PCA) degradation. A sulfhydryl group (-SH) masking experiment showed that the highly exposed Mn atoms on the 310-MnO2 surface were sites of PMS activation. In addition, density functional theory (DFT) calculations confirmed that the dominant {310} facet promoted adsorption/activation of PMS, which favored the formation of more metastable complexes on the α-MnO2 surface. The reaction mechanism obtained here clarifies the relationship between PMS activation and crystal facets. This study provides significant insights into the rational design of high-performance catalysts for efficient water remediation. [ABSTRACT FROM AUTHOR]

Atrazine contamination of water is of considerable concern because of the potential hazard to human health. In this study, a magnetic molecularly imprinted polymer for atrazine was prepared by the surface-imprinting technique using Fe 3 O 4 as the core, mesoporous silica as the carrier, atrazine as the template, and itaconic acid as the functional monomer. The magnetic molecularly imprinted polymer was characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, and vibration-sample magnetometry. The binding properties of the magnetic molecularly imprinted polymer toward atrazine were investigated by adsorption isotherms, kinetics, and competitive adsorption. It was found that the adsorption equilibrium was achieved within 2 h, the maximum adsorption capacity of atrazine was 8.8 μmol/g, and the adsorption process could be well described by the Langmuir isotherm model and pseudo-second-order kinetic model. The magnetic molecularly imprinted polymer exhibited good adsorption selectivity for atrazine with respect to structural analogues, such as cyanazine, simetryne, and prometryn. The reusability of the magnetic molecularly imprinted polymer was demonstrated for at least five repeated cycles without a significant decrease in adsorption capacity. These results suggested that the magnetic molecularly imprinted polymer could be used as an efficient material for the selective adsorption and removal of atrazine from water samples., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)