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Cancer is one of the leading causes of death worldwide. The development of novel anti-cancer agents from natural products is a promising approach to reduce cancer mortality. In this study, we investigated the anti-metastatic and anti-angiogenic activities of picroside II (PII) in human breast cancer cells both in vitro and in vivo. Our results demonstrated that PII significantly inhibited the migration and invasion of MDA-MB-231 cancer cells. With the treatment of PII, the activity of matrix metalloproteinase 9 (MMP-9) in MDA-MB-231 cancer cells was significantly inhibited both in vitro and in vivo. Meanwhile, PII showed effective anti-metastatic activity in an experimental lung metastasis model. Interestingly, cluster of differentiation 31 (CD31), a marker of angiogenesis, was significantly downregulated in the PII-treated tumor samples, indicating the anti-angiogenic activity of PII. Furthermore, we demonstrated that PII significantly inhibited the migration, invasion, and tube formation of human umbilical vein endothelial cells (HUVECs). The inhibition of MMP-9 activity in PII-treated HUVECs was also demonstrated. Finally, the suppression of angiogenesis by PII in the chick embryo chorioallantoic membrane (CAM) was observed. In conclusion, our results demonstrated that PII effectively inhibited the metastasis and angiogenesis of cancer cells both in vitro and in vivo, and thus, might be a novel candidate for cancer therapy., (Copyright © 2019 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Concomitance of diverse synaptic plasticity across different timescales produces complex cognitive processes. To achieve comparable cognitive complexity in memristive neuromorphic systems, devices that are capable of emulating short-term (STP) and long-term plasticity (LTP) concomitantly are essential. In existing memristors, however, STP and LTP can only be induced selectively because of the inability to be decoupled using different loci and mechanisms. In this work, the first demonstration of truly concomitant STP and LTP is reported in a three-terminal memristor that uses independent physical phenomena to represent each form of plasticity. The emerging layered material Bi 2 O 2 Se is used for memristors for the first time, opening up the prospects for ultrathin, high-speed, and low-power neuromorphic devices. The concerted action of STP and LTP allows full-range modulation of the transient synaptic efficacy, from depression to facilitation, by stimulus frequency or intensity, providing a versatile device platform for neuromorphic function implementation. A heuristic recurrent neural circuitry model is developed to simulate the intricate "sleep-wake cycle autoregulation" process, in which the concomitance of STP and LTP is posited as a key factor in enabling this neural homeostasis. This work sheds new light on the development of generic memristor platforms for highly dynamic neuromorphic computing., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Phase change materials (PCMs), such as Ge 2 Sb 2 Te 5 , are highly attractive in modern electronics and photonics. However, their spintronic applications remain largely unexplored. Here, we propose a tentative modality of phase change spintronic devices based on the ferromagnet/PCM/ferromagnet structure. The electrically tunable properties of a PCM interlayer give rise to new possibilities of manipulating spin transport through phase change, adding new functionalities and modes of operation to the spintronic devices. As the first step toward realizing such phase change spintronic devices, we calculate the electronic structures of the interfaces of c-Ge 2 Sb 2 Te 5 and half-metallic ferromagnetic Co 2 FeX (X: Al, Si). The interfaces are found not to be genuine half-metallic, indicating room for improvement. The band alignments are largely determined by the termination of c-Ge 2 Sb 2 Te 5 . Two types of band alignments are found for c-Ge 2 Sb 2 Te 5 /Co 2 FeX interfaces. Considering c-Ge 2 Sb 2 Te 5 as heavily p-type-doped, interfaces with Te termination are generally suitable such that they offer low contact resistance for hole injection from Co 2 FeX to c-Ge 2 Sb 2 Te 5 in the majority spin channel; at the same time, they naturally form tunneling barriers, alleviating the degradation of spin injection efficiency because of occasional hole injection in the minority spin channel. This work provides important insights into this proposed phase change spintronic framework., Competing Interests: The authors declare no competing financial interest.