Currently, the selective activation of C(sp
)-F bonds and C-C bonds constitute one of the most widely used procedures for the synthesis of high-value products that range from pharmaceuticals to ...agrochemical applications. While numerous examples of these two methods have been reported in their respective fields, the processes which merge the activation of both single C(sp
)-F bonds and C-C bonds in one step still remain elusive. Here, we demonstrate the controllable defluoroalkylation-distal functionalization of trifluoromethylarenes with unactivated alkenes via distal heteroaryl migration. This is proposed to proceed via tandem C(sp
)-F and C-C bond cleavage using visible-light photoredox catalysis combined with Lewis acid activation. This strategy provides facile and flexible access to multiply functionalized α,α-difluorobenzylic ketones in useful yields (up to 88%) under mild conditions. The products can be further transformed into other valuable compounds, demonstrating the method's utility.
We have systematically investigated the electrical transport properties of polycrystalline TaNx (0.83 ≲ x ≲1.32) films with rocksalt structure from 300 down to 2 K. It is found that the conductivity ...varies linearly with lnT from ∼6 to ∼30 K, which does not originate from the conventional two dimensional weak-localization or electron-electron interaction effects, but can be well explained by the intergrain Coulomb effect which was theoretically proposed in the granular metals. While the fluctuation-induced tunneling conduction process dominates the temperature behaviors of the conductivities (resistivities) above ∼60 K. Normal state to superconductive state transition is observed in the x ≳1.04 films in low temperature regime. The superconductivity can still be retained at a field of 9 T. The upper critical field increases linearly with decreasing temperature in the vicinity of the superconductive transition temperature, which is the typical feature of granular superconductors or dirty type-II superconductors. The granular-composite-like electrical transport properties of the polycrystalline TaNx films are related to their microstructure, in which the TaNx grains with high conductivity are separated by the poorly conductive amorphous transition layers (grain boundaries).
•The grain boundaries play key role in the electron transport processes of the polycrystalline TaNx films.•The transport properties of the polycrystalline TaNx films are similar to that of granular composite.•The upper critical field of the TaNx films (x ≥ 1.04) is greater than 9 T.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Scallop (
Patinopecten yessoensis
) female gonad hydrolysates (SFGHs) were obtained by using neutrase. The resulting hydrolysates possessed DPPH radical scavenging activity, ferrous ion-chelating ...ability, and reducing power with IC
50
or AC
0.5
values of 9.44, 0.94, and 5.88 mg/mL, respectively. SFGHs contained nearly 80 % of fractions with molecular weight around 250–5000 Da, and antioxidant-related amino acid residues in SFGHs reached to more than 30 %. Six fractions were separated from SFGHs on a Sephadex G-25 column, and one of the fractions with the highest DPPH radical scavenging activity was further analyzed by ESI-MS/MS, and a tetrapeptide His-Met-Ser-Tyr (536 Da) and a pentapeptide Pro-Glu-Ala-Ser-Tyr (565 Da) were identified. Both peptides showed hydroxyl radical scavenging activities with IC
50
values of 3.6 and 16.8 mM, respectively, by electron spin resonance method. These results imply that peptides derived from scallop female gonads are potent antioxidants and may be utilized as functional ingredients in food systems.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Bladder cancer is the most common malignancy of the urinary system. Compound Kushen Injection (CKI) is a Chinese medicinal preparation that has been widely used in the treatment of various types of ...cancers in the past two decades. However, the pharmacological effect of CKI on bladder cancer is not still completely understood. In the current study, network pharmacology combined with bioinformatics was used to elucidate the therapeutic mechanism and potential targets of CKI in bladder cancer. The mechanism by which CKI was effective against bladder cancer was further verified in vitro using human bladder cancer cell line T24. Network pharmacology analysis identified 35 active compounds and 268 target genes of CKI. Bioinformatics data indicated 5500 differentially expressed genes associated with bladder cancer. Common genes of CKI and bladder cancer suggested that CKI exerted anti-bladder cancer effects by regulating genes such as MMP-9, JUN, EGFR, and ERK1. Functional enrichment analysis indicated that CKI exerted therapeutic effects on bladder cancer by regulating certain biological processes, including cell proliferation, cell migration, and cell apoptosis. In addition, Kyoto Encyclopedia of Genes and Genomes enrichment analysis implicated pathways related to cancer, bladder cancer, and the PI3K-Akt signaling pathway. Consistently, cell experiments indicated that CKI inhibited the proliferation and migration of T24 cells, and induced their apoptosis. Moreover, RT-qPCR and Western blot results demonstrated that CKI was likely to treat bladder cancer by down-regulating the gene and protein expression of MMP-9, JUN, EGFR, and ERK1. CKI inhibited the proliferation and migration, and induced the apoptosis of T24 bladder cancer cells through multiple biological pathways and targets. CKI also exhibited significant effects on the regulation of key genes and proteins associated with bladder cancer. Overall, our findings provide solid evidence and deepen current understanding of the therapeutic effects of CKI for bladder cancer, and further support its clinical use.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Cluster of differentiation 8 (CD8) is expressed in cytotoxic T cells, where it functions as a co-receptor for the T-cell receptor by binding to major histocompatibility complex class I (MHCI) ...proteins, which present peptides on the cell surface. CD8A is critical for cell-mediated immune defense and T-cell development. CD8A transcription is controlled by several cis-acting elements and trans-acting elements and is also regulated by DNA methylation. However, the epigenetic regulation of CD8A in the duck and its relationship with virus infection are still unclear.
We investigated the epigenetic transcriptional regulatory mechanisms, such as DNA methylation, for the expression of the CD8A and further evaluated the contribution of such epigenetic regulatory mechanisms to DHV-I infection in the duck. Real-time quantitative polymerase chain reaction (RT-qPCR) revealed the highest level of CD8A expression to be in the thymus, followed by the lungs, spleen, and liver, and the levels of CD8A expression were very low in the kidney, cerebrum, cerebellum, and muscle in the duck. RT-qPCR also demonstrated that the CD8A mRNA was down-regulated significantly in morbid ducklings treated with DHV-1 and up-regulated significantly in non-morbid ducklings in all the tissues tested. In addition, hypermethylation of CD8A was detected in the morbid ducklings, whereas relatively low methylation of CD8A was evident in the non-morbid ducklings. The CD8A mRNA level was negatively associated with the CpG methylation level of CD8A and global methylation status.
We concluded that the mRNA level of the CD8A was negatively associated with the CpG methylation level of CD8A and global methylation status in the duck, suggesting that the hypermethylation of CD8A may be associated with DHV-1 infection. The first two CpG sites of the CD8A promoter region could be considered as epigenetic biomarkers for resistance breeding against duckling hepatitis disease in the duck.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The coordination polymers (CPs) Zn2(tipm)(1,3‐BDC)2 (1) and Co2(tipm)(1,3‐BDC)2·0.5CH3CN (2·0.5CH3CN) were synthesized by the reactions of Zn(NO3)2 or Co(NO3)2 with ...tetrakis4‐(1‐imidazolyl)phenylmethane (tipm) and benzene‐1,3‐dicarboxylic acid (1,3‐H2BDC) under solvothermal conditions. Compounds 1 and 2 are isostructural and possess complicated three‐dimensional frameworks with the Schläfli symbol (4·72)(62·73·12)(4·62·73). Cobalt ions were incorporated into the Zn‐based CP framework 1 during solvothermal crystallization to yield Zn(2–2x)Co2x(tipm)(1,3‐BDC)2·bH2O (x = 2.4 %, b = 0 for 1a, x = 23 %, b = 1 for 2a·H2O). Doped CPs 1a and 2a·H2O exhibited greater catalytic photodegradation of the dye rhodamine B (RhB) than the undoped complexes 1 and 2 and many literature examples.
Two coordination polymers are prepared, and their catalytic activity for the photodegradation of rhodamine B (RhB) is enhanced by doping with Co2+ ions.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Rapeseed contains glucosinolates, a toxic group of sulfur-containing glucosides, which play critical roles in defense against herbivores and microbes. However, the presence of glucosinolates in ...rapeseed reduces the value of the meal as feed for livestock. We performed association mapping of seed glucosinolate (GS) content using the 60K Brassica Infinium single nucleotide polymorphism (SNP) array in 520 oilseed rape accessions. A total of 11 peak SNPs significantly associated with GS content were detected in growing seasons of 2013 and 2014 and were located on B. napus chromosomes A08, A09, C03, and C09, respectively. Two associated regions of GS content covered by these markers were further verified, and three B. napus homologous genes involved in the biosynthesis and accumulation of GS were identified. These genes were multigene family members and were distributed on different chromosomes. Moreover, two genes (BnGRT2 and BnMYB28) associated with GS content were validated by the qRT-PCR analysis of their expression profiles. The further identification and functionalization of these genes will provide useful insight into the mechanism underlying GS biosynthesis and allocation in B. napus, and the associated SNPs markers could be helpful for molecular maker-assisted breeding for low seed GS in B. napus.
The yolk–shell-structured Fe
3
O
4
nanocomposite particles (Fe
3
O
4
@Void@C
–
N NPs) with Fe
3
O
4
as the yolk and N
-
doped carbon as the shell were prepared by using melamine formaldehyde resin as ...the N and C sources. When used as anode material for lithium ion battery, the yolk–shell structure could not only afford adequate void to accommodate the large volume change during charge/discharge process but also improve structural stability and electrical conductivity. The anode material demonstrated superior long-term and high-rate performance because of the novel structure and the N-doped carbon shell with mesopore. Thus, Fe
3
O
4
@Void@C–N NPs exhibited a high reversible capacity of 1530 mAh g
−1
after 300 cycles at a current density of 500 mA g
−1
, which were approximately 1.5 and 6 times higher than Fe
3
O
4
@C–N NPs and pure Fe
3
O
4
particles, respectively. Even at the higher current density of 2000 mA g
−1
, the reversible capacity remained at 651 mAh g
−1
after 500 cycles.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
•The ferroferric oxide/polystyrene/silver particles with a well-defined core–shell structure have been synthesized.•The composite particles provide excellent SERS performance and have a detecting ...limit of 10−10 M R6G.•The composite particles show superior stability and reproducibility for SERS application.
A novel Ag-coated Fe3O4@Polystyrene core–shell microsphere has been designed via fabrication of Fe3O4@Polystyrene core–shell magnetic microsphere through a seed emulsion polymerization, followed by deposition of Ag nanoparticles using in-situ reduction method. Such magnetic microspheres can be utilized as sensitive surface-enhanced Raman scattering (SERS) substrates, using Rhodamine 6G (R6G) as a probe molecule, with both stable and reproducible performances. The SERS detection limit of R6G decreased to 1×10−10 M and the enhancement factor of this substrate on the order of 106 was obtained. In addition, owing to possessing excellent magnetic properties, the resultant microspheres could be separated rapidly by an external magnetic field and utilized repeatedly for three times at least. Therefore, the unique renewable property suggests a new route to eliminate the single-use problem of traditional SERS substrates and will be promising for the practical application.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Yolk-shell nanocomposite particles (YSNPs) have been extensively investigated because of their great application potential and unique properties attributed to their distinct structures and multiple ...discrete functions. In this study, Fe
3
O
4
@Void@PMAA@Void@TiO
2
, a special YSNP with double shells and dual cavities (denoted as DDYSNPs), was prepared by conducting dispersion polymerization with a high production rate and by using a hydrothermal strategy. The synthesized DDYSNPs, which effectively integrate inorganic and organic functions, exhibit an outstanding photocatalytic activity under ultraviolet light irradiation for five experimental cycles and show an excellent adsorptive property for heavy metal ions. These comprehensive properties are mainly attributed to the novel structure of double-shelled and dual-cavity structures.
Graphical Abstract
ᅟ
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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