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Neointimal hyperplasia is the major cause of carotid stenosis after vascular injury, which restricts the long-term efficacy of endovascular treatment and endarterectomy in preventing stenosis. Ginsenoside Re (Re) is a major active ingredient of ginseng having multifaceted pharmacological effects on the cardiovascular system, and is a potential treatment for restenosis. In this study, we demonstrated that Re treatment significantly inhibited vascular injury-induced neointimal thickening, reduced the intimal area and intima/media (I/M) ratio, increased the lumen area, and inhibited pro-inflammatory cytokines. In cultured A7R5 cells, Re inhibited LPS-induced proliferation and migration as evidenced by suppressed colony formation and shortened migration distance, accompanied by the downregulated expression of pro-inflammatory cytokines. Re promoted VSMC apoptosis induced by balloon injury in vivo and LPS challenge in vitro. Moreover, Re inhibited autophagy in VSMCs evoked by balloon injury and LPS as supported by reduced LC3II and increased p62 expressions. Suppression of autophagy with the specific autophagy inhibitor spautin-1 efficiently inhibited LPS-induced cell proliferation and inflammation and promoted caspase-3/7 activities. Mechanistically, we found that Re attenuated Ras/ERK1/2 expression in VSMCs in vivo and in vitro. The MEK1/2 inhibitor PD98059 showed similar effects to Re on cell proliferation, migration, apoptosis, and the levels of autophagy and cytokines. In conclusion, we provided significant evidence that Re inhibited vascular injury-induced neointimal thickening probably by promoting VSMC apoptosis and inhibiting autophagy via suppression of the Ras/MEK/ERK1/2 signaling pathway.

Vascular tree disentanglement and vessel type classification are two crucial steps of the graph-based method for retinal artery-vein (A/V) separation. Existing approaches treat them as two independent tasks and mostly rely on ad hoc rules (e.g. change of vessel directions) and hand-crafted features (e.g. color, thickness) to handle them respectively. However, we argue that the two tasks are highly correlated and should be handled jointly since knowing the A/V type can unravel those highly entangled vascular trees, which in turn helps to infer the types of connected vessels that are hard to classify based on only appearance. Therefore, designing features and models isolatedly for the two tasks often leads to a suboptimal solution of A/V separation. In view of this, this paper proposes a multi-task siamese network which aims to learn the two tasks jointly and thus yields more robust deep features for accurate A/V separation. Specifically, we first introduce Convolution Along Vessel (CAV) to extract the visual features by convolving a fundus image along vessel segments, and the geometric features by tracking the directions of blood flow in vessels. The siamese network is then trained to learn multiple tasks: i) classifying A/V types of vessel segments using visual features only, and ii) estimating the similarity of every two connected segments by comparing their visual and geometric features in order to disentangle the vasculature into individual vessel trees. Finally, the results of two tasks mutually correct each other to accomplish final A/V separation. Experimental results demonstrate that our method can achieve accuracy values of 94.7%, 96.9%, and 94.5% on three major databases (DRIVE, INSPIRE, WIDE) respectively, which outperforms recent state-of-the-arts.

Sorafenib, a multi-kinase inhibitor, is recommended as a new standard therapy for advanced hepatocellular carcinoma (HCC); however, it also exhibits severe cardiotoxicity and the toxicity mechanisms are not completely elucidated. Recent studies suggested that sorafenib-enhanced ROS may partially contribute to its anti-HCC effect, which implies that redox mechanism might also be involved in sorafenib's cardiotoxicity. In this study, we aimed to investigate if sorafenib is able to induce oxidative stress and how this may impair cellular functions in cardiomyocyte, ultimately accounting for its cardiotoxicity. Our results showed that in isolated rat hearts, sorafenib caused ventricular arrhythmias and left ventricular dysfunction, which were alleviated by the antioxidant N-(2-mercaptopropionyl)-glycine (MPG). In isolated ventricular myocytes, sorafenib increased diastolic intracellular Ca2+ levels, decreased Ca transients and the occurrence of Ca2+ waves. These changes were eliminated by MPG, CaMKII inhibitor KN-93 and the mitochondrial permeability transition pore (mPTP)inhibitor cyclosporin A (CsA). Moreover, the levels of oxidized and phosphorylated CaMKII were significantly increased. Sorafenib elevated ROS levels, which was reversed by CsA and MPG; additionally, sorafenib reduced the activity of mitochondrial complex III and augmented mitochondrial ROS production. In vivo rats treated with sorafenib exhibited a reduction of antioxidant defence and abnormal histological alterations including hypertrophy, increased fibrosis, disordered myofibrils and damaged mitochondria, which were protected by MPG. We conclude that sorafenib induces the disruption of Ca2+ homoeostasis and cardiac injury via enhanced ROS potentially through inhibiting mitochondrial complex III, the opening of mPTP and overactivating CaMKII. These results provide a potential strategy for preventing or reducing cardiotoxicity of sorafenib.

A series of mesoporous nano-MgO-ZrO2 with various Mg:Zr atomic ratios were prepared via simple co-precipitation process without addition of a template. It was demonstrated by XRD, N2 adsorption-desorption and TEM that these samples still kept well mesoporous structure even after calcination at 600 °C. During the preparation process, divalent Mg2+ ions could be incorporated into tetragonal ZrO2 lattice to form a solid solution. More important, the surface basic density of these catalysts closely depended on their Mg content. Then, the resulting MgO-ZrO2 catalysts were used as basic catalysts for the dipropyl carbonate (DPC) synthesis via transesterification of n-propanol and dimethyl carbonate. The relationship between the basic property of solid base and their catalytic performance was clarified in detail. Among all the materials, the catalyst with Mg:Zr atomic ratio = 0.5 showed the best catalytic performance. Under the suitable reaction conditions, the yield of DPC could reach 98.5% with 100% selectivity. In addition, based on the reusability test and catalyst characterization, this catalyst exhibited extraordinary structure stability and it could be reused at least four times without obvious loss of reactivity.

To meet the challenge of continuously increasing global energy demands, organic-inorganic halide based perovskite solar cells (PSCs) have garnered great attention from the photovoltaic research community for their low cost and high efficiency. The efficiency of perovskite-based mesoscopic solar cells increases rapidly, from 3.8% in 2009 to 22.1% in 2016. N-type metal-oxide electron transport layer, as one of the important components in mesoscopic PSCs (MPSCs), acts as not only a scaffold layer for the growth of perovskite crystals, but also a layer to supply transfer pathways for electrons injected from perovskites. In this review, we discussed recent published reports of MPSCs with the focus on n-type metal-oxide electron transport layer in MPSCs. The scaffold materials, scaffold nanostructure, and scaffold/perovskite interface engineering are considered, and the effects of these modifications of scaffolds on the performance of MPSCs are summarized in this review.

A printing process for the fabrication of perovskite solar cells (PSCs) exhibits promising future application in the photovoltaic industry due to its low-cost and eco-friendly preparation. In mesoscopic carbon-based PSCs, however, compared to conventional ones, the hole-transport-layer-free PSCs often lead to inefficient hole extraction. Here, we used liquid metal (LM, Galinstan) as an interface modifier material in combination with a carbon electrode. Considering the high conductivity and room-temperature fluidity, it is found that LMs are superior in improving hole extraction and, more importantly, LMs tend to be reserved at the interface between ZrO2 and carbon for enhancing the contact property. Correspondingly, the carrier transfer resistance was decreased at the carbon/perovskite interface. As optimized content, the triple mesoscopic PSCs based on mixed-cation perovskite with a power conversion efficiency of 13.51% was achieved, involving a 26% increase compared to those without LMs. This work opens...