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Intracranial hemorrhage (ICH) is the most common acute progressive cerebrovascular disease in aging population. Although the pathogenesis of ICH remains unclear, a great many mechanism researches have shown that the blood⁃brain barrier (BBB) regulated by different genetic factors may play an important role. As classic animal model for hemorrhagic cerebrovascular disease, the ICH zebrafish model plays a key role in the studies for mechanisms of genetic factors. In this article, we comprehensively reviews the characteristics and advantages of ICH zebrafish model, and also makes an updated introductions on genetic and molecular aspects of BBB structures and functions based on common transgenic ICH zebrafish model. Therefore, we explain the relationship between ICH and related gene expression, in order to deepen current understanding on ICH pathogenesis and help to make relevant strategy for prevention and treatment. doi：10.3969/j.issn.1672⁃6731.2021.02.005

An asymmetric decarboxylative Mannich reaction of phosphonate sultam‐ketimines with malonic acid half esters is developed enabled by saccharide‐derived bifunctional amino thiourea catalysis. This protocol provides access to a broad range of α‐amino‐β‐carboxylic phosphonates featuring the N,P‐containing tetrasubstituted stereocenters with 78–99% ee. Further synthetic derivatizations could allow the introduction of amide, alcohol, and azetidine scaffolds to the core structures. [ABSTRACT FROM AUTHOR]

Compared with red and green perovskite light‐emitting diodes (PeLEDs), blue PeLEDs are still unable to well control spectral stability due to the issues of ion migration and phase separation under external operating conditions. Herein, a strategy using organometallic ligands is reported to achieve spectrally stable PeLEDs. The obtained perovskite film exhibits stable photoluminescence spectra under UV excitation (365nm) and continuous heating of 70 °C. The device delivers an external quantum efficiency (EQE) of 6.7% with 50% lifetime (T50) of 21.6 min. Under high driving voltage (from 2 to 7.5 V), no obvious spectral shift has occurred for the electroluminescence spectrum at 481 nm. This work confirms the positive effect of organometallic ligands in quasi‐2D perovskite and provides a new idea for proposing effective ligands to act on the perovskite luminescence layer in the future. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the neglect of left-behind children (LBC) in China. Method: Participants: Children separated from one or both parents for at least 6 months. Intervention: Trauma of separation. Comparison: Non-left-behind children (NLBC). Outcomes: Neglect rates and severity. Only case–control studies were included. Results: Thirteen studies were included; there were 18,688 LBC in a large sample (N = 42,003) of children aged 0–18 years in China. The overall neglect rate was significantly higher in LBC compared to NLBC (odds ratio [ OR ] = 1.58, 95% confidence interval [CI] = [1.50, 1.67], p <.01) based on the Chinese Rural Child Neglected Evaluation Model (CRCNEM) and the Parents–Child Conflict Tactics Scales (OR = 1.44, 95% CI [1.35, 1.54], p <.01). The overall neglect severity in LBC was also significantly higher than NLBC (SMD = 0.31, 95% CI [0.28, 0.33], p <.01). The same trends were observed in sex subgroups. With regard to subtypes, LBC were significantly more likely to have emotional neglect (OR = 2.29, 95% CI [1.88, 2.78], p <.01), medical neglect (OR = 1.79, 95% CI [1.62, 1.98], p <.01), physical neglect (OR = 1.75, 95% CI [1.60, 1.91], p <.01), security neglect (OR = 1.52, 95% CI [1.32, 1.75], p <.01), educational neglect (OR = 1.50, 95% CI [1.31, 1.72], p <.01), and social neglect (OR = 1.33, 95% CI [1.18, 1.51], p <.01). Furthermore, LBC had significantly higher severity in medical neglect (SMD = 0.31, 95% CI [0.27, 0.35], p <.01), emotional neglect (SMD = 0.28, 95% CI [0.24, 0.32], p <.01), physical neglect (SMD = 0.24, 95% CI [0.18, 0.29], p <.01), security neglect (SMD = 0.26, 95% CI [0.23, 0.29], p <.01), educational neglect (SMD = 0.25, 95% CI [0.20, 0.31], p <.01), and social neglect (SMD = 0.25, 95% CI [0.10, 0.40], p <.01). Conclusion: The neglect rates and severity in LBC in China were both significantly higher than those in NLBC. There was a strong association between neglect and LBC. Public policy changes are urgently needed to improve the dire situation and the well-being of the LBC. [ABSTRACT FROM AUTHOR]

Genistein, a soy derived isoflavanoid compound, exerts anticancer effects in various cancers. Nasopharyngeal cancer stem cells (NCSCs) are a small subpopulation of cancer cells which are responsible for initiation, progression, metastasis, and recurrence of nasopharyngeal cancer. The present study aimed to investigate the suppressive effects of genistein on NCSCs and its underlying mechanism. NCSCs were enriched from human nasopharyngeal cancer cell lines CNE2 and HONE1 through tumorsphere-forming assay. It was shown that genistein inhibited the tumorsphere formation capacity, decreased the number of EpCAM+ cells, downregulated the expression of NCSCs markers, suppressed cell proliferation, and induced apoptosis of NCSCs. Genistein suppressed the activity of Sonic hedgehog (SHH) signaling, which was important for the maintenance of NCSCs, while activation of SHH signaling by purmorphamine diminished the inhibitory effects of genistein on NCSCs. Our data suggested that genistein inhibited NCSCs through the suppression of SHH signaling. These findings support the use of genistein for targeting NCSCs. [ABSTRACT FROM AUTHOR]

Cancer stem cells (CSCs) are considered to play essential roles in the process of origination, proliferation, migration, and invasion of cancer, and their properties are regulated by Wnt/β-catenin pathway. Phenethyl isothiocyanate (PEITC) is a natural product obtained from cruciferous vegetables with anticancer activities. The present study aimed to investigate the inhibitory effect and the underlying mechanisms of PEITC on colorectal CSCs. In this study, we found that PEITC can significantly reduce the size and number of colorectal cancer cell spheroids in serum-free medium. With increasing PEITC concentrations (10-40 μM), the number of spheroids was reduced to about 10% of the control group, and the percentage of CD133+ cells was decreased by about 3-16 folds. PEITC also decreased the expression of CSC markers. Meanwhile, inhibition of proliferation as well as induction of apoptosis of colorectal CSCs was observed after PEITC treatment. Furthermore, through activating Wnt/β-catenin pathway with LiCl, the inhibitory effects of PEITC on colorectal CSCs were diminished. Our data suggested that PEITC can be an effective inhibitor of colorectal CSCs by targeting Wnt/β-catenin pathway. [ABSTRACT FROM AUTHOR]

Multi‐layer π‐stacked emitters based on spatially confined donor/acceptor/donor (D/A/D) patterns have been developed to achieve high‐efficiency thermally activated delayed fluorescence (TADF). In this case, dual donor moieties and a single acceptor moiety are introduced to form two three‐dimensional (3D) emitters, DM‐BD1 and DM‐BD2, which rely on spatial charge transfer (CT). Owing to the enforced face‐to‐face D/A/D pattern, effective CT interactions are realized, which lead to high photoluminescence quantum yields (PLQYs) of 94.2 % and 92.8 % for the two molecules, respectively. The resulting emitters exhibit small singlet–triplet energy splitting (ΔEST) and fast reverse intersystem crossing (RISC) processes. Maximum external quantum efficiencies (EQEs) of 28.0 % and 26.6 % were realized for devices based on DM‐BD1 and DM‐BD2, respectively, which are higher than those of their D/A‐type analogues. [ABSTRACT FROM AUTHOR]

Remote functionalization reactions have the power to transform a C−H (or C−C) bond at a distant position from a functional group. This Review summarizes recent advances and key breakthroughs in remote fluorination, trifluoromethylation, difluoromethylation, trifluoromethylthiolation, and fluoroalkenylation reactions. Several powerful strategies have emerged to control the reactivity and distal selectivity such as the undirected radical approach, the 1,5‐hydrogen atom transfer, the metal migration, the use of distant directing groups, and the ring‐opening reactions. These unconventional and predictable C−H (and C−C) functionalization transformations should allow for the preparation of a wide range of otherwise‐difficult‐to‐access alkyl, aromatic, heteroaromatic, and structurally complex fluorides. [ABSTRACT FROM AUTHOR]

With the inherent organic–metal system property, phosphorescent organic light‐emitting diodes (PhOLEDs) are capable of exhibiting high performance. However, the existence of unintended triplet–triplet annihilation (TTA), which is mainly originated from high triplet exciton density leading to inferior device performance, is a current predicament. For mitigating the TTA in devices, reported herein is an effective host system with the role of precisely controlling the triplet excitons via the multichannel processes, in which a bipolar host material, a hole‐transporting material, and an electron‐transporting material are mixed to manage the triplet exciton transfer. The mixed‐host with so‐called "triplet excitons harvesting" strategy exhibits two concomitant reverse intersystem crossing (RISC) processes that simultaneously occur in the bipolar host material:electron‐transporting material and the host‐transporting material:electron‐transporting material exciplexes, respectively. Highly efficient green and red PhOLEDs are demonstrated by these multichannel processes, in which phosphorescent emitters bis(2‐phenylpyridine) (acetylacetonate) iridium(III) (Ir(ppy)2(acac)) and bis(2‐methyldibenzo[f,h]‐quinoxaline) (acetylacetonate) iridium(III) (Ir(MDQ)2(acac)) are doped into the mixed‐host, respectively. The green and red PhOLEDs realize nearly 30% of maximum external quantum efficiencies of 29.4% and 29.2%, respectively, and also maintain 29.1% and 28.3% at 1000 cd m−2. These excellent efficiencies and low roll‐offs confirm that the concomitant RISC processes effectively manage and utilize triplet excitons. [ABSTRACT FROM AUTHOR]

With the rapid development of railway construction in our country there is a huge demand for concrete. According to the requirements of document No. [2005] 160 concrete mixing stations should be set up according to the construction project scale and the demand for concrete. Therefore the selection of the location of concrete mixing stations becomes very important. Based on a holistic consideration of the construction cost on railway concrete mixing station demolition and ecological restoration transportation distance and other factors the optimal location model of railway concrete mixing station is established and solved by genetic algorithm. Through a specific example this model and its algorithm are solved and the optimal scheme is determined which confirms the feasibility of the model in the optimizing the site selection of railway concrete mixing station and the effectiveness of its algorithm. It provides important theoretical support and practical ideas for selecting the location of railway concrete mixing station. [ABSTRACT FROM AUTHOR]

Keywords: 1,5-hydrogen atom transfer; fluorination; fluoroalkyl(thiol)ation; metal migration; remote functionalization EN 1,5-hydrogen atom transfer fluorination fluoroalkyl(thiol)ation metal migration remote functionalization 1 1 1 12/03/20 20201201 NES 201201 B Remote functionalization reactions b have the power to transform a C-H (or C-C) bond at a distant position from a functional group. 1,5-hydrogen atom transfer, fluorination, fluoroalkyl(thiol)ation, metal migration, remote functionalization. [Extracted from the article]

Outcomes for metastatic Ewing sarcoma and osteosarcoma are dismal and have not changed for decades. Oxidative stress attenuates melanoma metastasis, and melanoma cells must reduce oxidative stress to metastasize. We explored this in sarcomas by screening for oxidative stress sensitizers, which identified the class I HDAC inhibitor MS‐275 as enhancing vulnerability to reactive oxygen species (ROS) in sarcoma cells. Mechanistically, MS‐275 inhibits YB‐1 deacetylation, decreasing its binding to 5′‐UTRs of NFE2L2 encoding the antioxidant factor NRF2, thereby reducing NFE2L2 translation and synthesis of NRF2 to increase cellular ROS. By global acetylomics, MS‐275 promotes rapid acetylation of the YB‐1 RNA‐binding protein at lysine‐81, blocking binding and translational activation of NFE2L2, as well as known YB‐1 mRNA targets, HIF1A, and the stress granule nucleator, G3BP1. MS‐275 dramatically reduces sarcoma metastasis in vivo, but an MS‐275‐resistant YB‐1K81‐to‐alanine mutant restores metastatic capacity and NRF2, HIF1α, and G3BP1 synthesis in MS‐275‐treated mice. These studies describe a novel function for MS‐275 through enhanced YB‐1 acetylation, thus inhibiting YB‐1 translational control of key cytoprotective factors and its pro‐metastatic activity. Synopsis: Class 1 HDAC inhibitors including MS‐275 inhibit the RNA binding protein YB‐1 by enhancing its acetylation. This reduces its affinity to mRNA targets under cellular stress, and decreases tumor cell fitness and metastatic capacity. YB‐1 translationally activates NRF2 synthesis under oxidative stress.MS‐275‐mediated YB‐1 acetylation reduces translation of multiple YB‐1 translational targets.MS‐275 blocks metastasis of childhood sarcoma cell lines and PDX tumors in pre‐clinical models. [ABSTRACT FROM AUTHOR]

Deep‐red and near‐infrared emitters with twisted donor–acceptor (D–A) structures often exhibit suboptimal performance in organic light‐emitting diodes (OLEDs) due to constraints imposed by the energy gap law. In this work, a pure hydrogen carbon (PHC) host material named SBF‐DTP is purposefully tailored for deep‐red OLEDs. The excellent capacity of SBF‐DTP to support D–A type DR emitters effectively arises from its distinctive attributes: localized excitation states, 3D configuration, and low polarity. When employing SBF‐DTP as the host for the fluorescence emitter DCPA‐TPA and the thermally activated delayed fluorescence emitter APDC‐DTPA, doped films exhibit substantially enhanced photoluminescence quantum yields. This improvement leads to high‐efficiency OLEDs with external quantum efficiencies of 5.47% for DCPA‐TPA and 20.03% for APDC‐DTPA, respectively, which is about twice as high as the initial reports. This findings underscore the paramount significance of developing efficient host materials in the pursuit of high‐performance deep red and even near‐infrared OLEDs. [ABSTRACT FROM AUTHOR]

Epithelial-mesenchymal transition (EMT) contributes to the initiation, invasion, metastasis and drug resistance of cancer. The function of extracellular signal-regulated kinase 5 (ERK5) in lung cancer progression remains elusive. In this study, we investigated the effect of sulforaphane (SFN) on lung cancer EMT and the role of ERK5 in its effect. Wound healing and Transwell assays were applied to examine the migratory and invasive capacity in vitro. Quantitative real-time polymerase chain reaction and immunoblotting analysis were performed to investigate the expression of mRNA and protein levels. Small-interfering RNA was used to silence ERK5. Xenograft model was used to confirm the effect of SFN in vivo. Enhanced EMT and decreased ERK5 activation were observed in lung cancer cells in comparison with normal human bronchial epithelial cells. SFN diminished the migratory and invasive capacity of lung cancer cells. Additionally, significantly increased expression of epithelial markers (E-cadherin and ZO-1), decreased expression of mesenchymal markers (N-cadherin and Snail1) and activation of ERK5 were observed after SFN treatment. The inhibitory effect of SFN on lung cancer cell EMT was attenuated by ERK5 silencing. SFN-induced EMT suppression and ERK5 activation were further confirmed in lung cancer xenograft mouse model. The present study illustrated for the first time that ERK5 activation mediates SFN suppression of lung cancer cell EMT. These findings could provide new insights into the function of ERK5 in EMT regulation and the potential therapeutic application of SFN in cancer intervention. [ABSTRACT FROM AUTHOR]