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Gallbladder cancer is a rare but fatal malignancy. However, the mechanisms underlying gallbladder carcinogenesis and its progression are poorly understood. The function of m6A modification and its regulators was still unclear for gallbladder cancer. The current study seeks to investigate the function of YTH m6A RNA‐binding protein 1 (YTHDF1) in gallbladder cancer. Transcriptomic analysis and immunochemical staining of YTHDF1 in gallbladder cancer tissues revealed its upregulation compared to paracancerous tissues. Moreover, YTHDF1 promotes the proliferation assays, Transwell migration assays, and Transwell invasion assays of gallbladder cancer cells in vitro. And it also increased tumour growth in xenograft mouse model and metastases in tail vein injection model in vivo. In vitro, UHRF1 knockdown partly reversed the effects of YTHDF1 overexpression. Mechanistically, dual‐luciferase assays proved that YTHDF1 promotes UHRF1 expression via direct binding to the mRNA 3′‐UTR in a m6A‐dependent manner. Overexpression of YTHDF1 enhanced UHRF1 mRNA stability, as demonstrated by mRNA stability assays, and Co‐IP studies confirmed a direct interaction between YTHDF1 and PABPC1. Collectively, these findings provide new insights into the progression of gallbladder cancer as well as a novel post‐transcriptional mechanism of YTHDF1 via stabilizing target mRNA. [ABSTRACT FROM AUTHOR]

N6‐methyladenosine (m6A) is the most abundant internal modification in eukaryotic RNA and involved in the carcinogenesis of various malignancies. However, the functions and mechanisms of m6A in gallbladder cancer (GBC) remain unclear. In this study, we investigated the role and underlying mechanism of the RNA‐binding protein YT521‐B homology domain‐containing family protein 2 (YTHDF2), an m6A reader, in GBC. Herein, we detected that YTHDF2 was remarkably upregulated in GBC tissues compared to normal gallbladder tissues. Functionally, YTHDF2 overexpression promoted the proliferation, tumor growth, migration, and invasion of GBC cells while inhibiting the apoptosis in vitro and in vivo. Conversely, YTHDF2 knockdown induced opposite results. Mechanistically, we further investigated the underlying mechanism by integrating RNA immunoprecipitation sequencing (RIP‐seq), m6A‐modified RIP‐seq, and RNA sequencing, which revealed that death‐associated protein kinase 3 (DAPK3) is a direct target of YTHDF2. YTHDF2 binds to the 3′‐UTR of DAPK3 mRNA and facilitates its degradation in an m6A‐dependent manner. DAPK3 inhibition restores the tumor‐suppressive phenotype induced by YTHDF2 deficiency. Moreover, the YTHDF2/DAPK3 axis induces the resistance of GBC cells to gemcitabine. In conclusion, we reveal the oncogenic role of YTHDF2 in GBC, demonstrating that YTHDF2 increases the mRNA degradation of the tumor suppressor DAPK3 in an m6A‐dependent way, which promotes GBC progression and desensitizes GBC cells to gemcitabine. Our findings provide novel insights into potential therapeutic strategies for GBC. [ABSTRACT FROM AUTHOR]

Heterogeneous catalysis is an important way to realize green chemistry. Developing excellent heterogeneous catalysts by using appropriate supports is still a mainstream research area. Polyacrylonitrile fiber (PANF), a common textile material in our daily life, has excellent advantages of low cost, high strength, light density, mildew resistance, etc. Furthermore, PANF can be knitted into varieties of shapes, making them very suitable for fixed‐bed catalysis in industries. Consequently, PANF is a fine raw material for the synthesis of heterogeneous catalysts. Therefore, more and more PANF‐based heterogeneous catalysts had been developed and applied to various of reaction systems. In this paper, the research progress of PANF‐based catalysts was reviewed, and the research progress of different PANF catalytic systems and their applications in green chemistry were emphatically introduced, which provided reference to the development of PANF‐supported catalytic technology. Finally, the catalytic system supported by PANF is summarized and prospected. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the adsorption of carbonic acid and water molecules on the (010) surface of γ‐dicalcium silicate (γ‐C2S) at an atomic scale using density functional theory (DFT) and ab initio molecular dynamics. It provides novel insights into the mechanism of carbonation on the surface of γ‐C2S. The electrons transfer and interfacial reactions between the carbonic acid (H2CO3) molecule and the γ‐C2S surface are characterized by adsorption configuration, bond order, electron density difference, and partial density of states. There exist strong interactions between H2CO3 and γ‐C2S surface, including two types of chemical adsorption and one type of physical adsorption. This work confirms that water in the carbonation of γ‐C2S is to react with CO2 to provide the reactants, and protons transfer of the carbonic acid molecule plays a crucial role in the carbonation process. The adsorption of the carbonic acid molecule is more favorable with respect to that of the water molecule, which may be the initial step of the carbonization of γ‐C2S. [ABSTRACT FROM AUTHOR]

Defects causing concomitant loss of CD25 expression in regulatory T cells (Tregs) have been identified in systemic lupus erythematosus (SLE). However, the cause of this deficiency is not fully understood. Carcinoembryonic antigen related cell adhesion molecule 1 (CEACAM1), an immune co‐receptor, contributes to general T‐cell function and activation. Our previous study revealed that CEACAM1 expression was upregulated in peripheral blood mononuclear cells (PBMCs) from patients with SLE. However, its role remains unclear. Herein, we confirmed CEACAM1, especially CEACAM1‐S, was upregulated in PBMCs from patients with SLE. CEACAM1‐S over‐expression inhibits CD4+CD25+ Treg differentiation, whereas knockdown of CEACAM1 had the opposite effect in vitro. CEACAM1‐S is the target of miR‐31. MiR‐31 mimic inhibits CEACAM1 expression and enhances CD4+CD25+ Treg differentiation, which was reversed by CEACAM1‐S over‐expression. Moreover, the circulating TGF‐β level was upregulated in SLE patients and TGF‐β reduced miR‐31 expression via enhancing NF‐κB activity. Importantly, CEACAM1 and TGF‐β mRNA levels were downregulated, while the miR‐31 level and the abundance of CD4+CD25+ Tregs were increased in inactive patients compared with that in patients with active SLE. In addition, CEACAM1‐S expression was positively correlated with the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score, while CD4+CD25+ Treg abundance and miR‐31 level were negatively correlated with the SLEDAI score. In conclusion, reduced activity of miR‐31 by TGF‐β, via the inhibition of NF‐ᴋB, acted to inhibit the differentiation of CD4+CD25+ Tregs by directly targeting CEACAM1‐S and to promote autoimmunity. [ABSTRACT FROM AUTHOR]

Illustrating the influence of Fe dosage and temperature on the formation of sulfoaluminate hydrates is of great significance to understand the early hydration process of high ferrite cement under steam curing. Herein, the impact of Fe dosage on the ettringite formation at different temperatures was revealed through the combination of experiments and computational simulations. A Fe dosage no more than 20% conspicuously accelerated the crystal growth of ettringite by increasing the surface energy in the (0 0 1) direction, whereas a higher dosage suppressed the formation of ettringite as the high incorporation of Fe ions into the ettringite crystal was energetically unstable. The chemical environment analysis of Fe in products shows that Fe(OH)63−, compared with Al(OH)63−, prefers to participate in the formation of Al2O3‐Fe2O3‐mono than ettringite, which is also confirmed by the calculated thermodynamic properties' results. The understanding of the impact and mechanism of Fe on the formation of ettringite under steam curing conditions plays a pivotal role in the utilization of high ferrite cement. [ABSTRACT FROM AUTHOR]

Brownmillerite‐type oxides are a large family of structural and functional materials that are of great concern. In this study, the occupancy mechanism of Fe and Al ions in brownmillerite Ca2FeAlO5 is revealed and the specific configuration of Ca2FeAlO5 is proposed for the first time. Through the energy analysis of a series of conjectured models based on well‐defined ab initio calculations, we find that the distribution of Al and Fe in Ca2FeAlO5 follows the "homogeneous layer principle", namely, Al and Fe tend to form homogeneous octahedral layers or tetrahedral chains rather than mixed layers or chains of two elements along the b axis. The theoretical Ca2FeAlO5 structure with specific atomic occupancy is proposed based on energy analysis and previous experiments, which is of fundamental significance for further study of its physical and chemical properties. Moreover, the influence of entropy increment on the stability of Ca2FeAlO5 crystal is clarified, which paves the way to investigate the structures and properties of Ca2FeAlO5 and other brownmillerite members. [ABSTRACT FROM AUTHOR]

Myeloid‐derived suppressor cells (MDSCs) are functionally immunosuppressive cells that are persistently increased in abundance and associated with adverse clinical outcomes in sepsis. Here, we investigated the therapeutic potential of an anaplastic lymphoma kinase inhibitor, LDK378, in cecal ligation and puncture (CLP)‐induced polymicrobial sepsis and examined its effects on the recruitment of MDSCs. LDK378 significantly improved the survival of CLP‐induced polymicrobial septic mice, which was paralleled by reduced organ injury, decreased release of inflammatory cytokines and decreased recruitment of MDSCs to the spleen. Importantly, LDK378 inhibited the migration of MDSCs to the spleen by blocking the CLP‐mediated upregulation of CC chemokine receptor 2 (CCR2), a chemokine receptor critical for the recruitment of MDSCs. Mechanistically, LDK378 treatment blocked the CLP‐induced CCR2 upregulation of MDSCs via partially inhibiting the phosphorylation of p38 and G‐protein‐coupled receptor kinase‐2 (GRK2) in bone marrow MDSCs of septic mice. Furthermore, in vitro experiments also showed that lipopolysaccharide (LPS)‐induced migration of MDSCs was similarly owing to the activation of GRK2 and upregulation of CCR2 by LPS, whereas the treatment with LDK378 partially blocked the LPS‐induced phosphorylation of p38 and GRK2 and decreased the expression of CCR2 on the cell surface, therefore leading to the suppression of MDSC migration. Together, these findings unravel a novel function of LDK378 in the host response to infection and suggest that LDK378 could be a potential therapeutic agent for sepsis. [ABSTRACT FROM AUTHOR]

Converting renewable biomass and their derivatives into chemicals and fuels has received much attention to reduce the dependence on fossil resources. Photocatalytic ethanol dehydrogenation–acetalization to prepare value‐added 1,1‐diethoxyethane and H2 was achieved over non‐precious metal CdS/Ni‐MoS2 catalyst under visible light. The system displays an excellent production rate and high selectivity of 1,1‐diethoxyethane, 52.1 mmol g−1 h−1 and 99.2 %, respectively. In‐situ electron spin resonance, photoluminescence spectroscopy and transient photocurrent responses were conducted to investigate the mechanism. This study provides a promising strategy for a green application of bioethanol. Remove hydrogen and acetalize: Photocatalytic ethanol dehydrogenation–acetalization to prepare value‐added 1,1‐diethoxyethane and H2 was achieved over non‐precious metal CdS/Ni‐MoS2 catalyst under visible light. This work provides a promising strategy for a green atom‐economic application of bioethanol. [ABSTRACT FROM AUTHOR]

Abstract: Ettringite and thaumasite are 2 of the relevant secondary products in portland cement minerals. They are rare crystals with high water content. Two density functional theory based ab initio packages VASP and the OLCAO were used for exploring the geometry structure, electronic, and mechanical properties of ettringite and thaumasite. The calculations focus on the comparison of their structures and properties to gain insights that can reveal the minute difference in properties due to differences in their structure, composition and water content. Detailed analysis of interatomic bonding shows the similarities and subtle difference between them even though thaumasite has the Si tetrahedron as the backbone unit in contrast to ettringite with Al‐columns and no Si atoms. Moreover, thaumasite has strong C–O bonds that are absent in ettringite, and ettringite has far more water molecules with a substantial contribution from the hydrogen bonding. It is shown that the role played by relatively strong S–O bonds in both crystals has a large impact on the hydration in these crystals. On the basis of calculated total bond order density, it is concluded that thaumasite is slightly more cohesive than ettringite consistent with the calculated mechanical properties. The detailed comparative results for these 2 important minerals we obtained in this paper, many of them for the first time, will pave the way to understanding the structure and electronic structure origin of other more complex cement crystals. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the doping behavior of impurity ions in clinker phases is crucial for controlling the doping effect on clinker compounds, which, however, has not yet been fully demonstrated due to the composition complexity. Herein, we employ the state‐of‐the‐art ab initio calculation to uncover the substitution mechanism of Cu ions in 4 dominant clinker crystals. The defect formation energies indicate Cu ions energetically prefer to substitute Fe ions in ferrite, which is in accord with the experiments. The bond order difference is innovatively postulated to interpret the energy barriers of Cu substitution in comparison with the ionic radius criterion. The high potential barriers of Cu substituting Ca, Si, and Al ions are ascribed to their bond order mismatch, while the tendency of Cu replacing Fe is due to their bond order similarity. Namely, the Cu doping in clinker phases follows the “bond order conformity” principle. In‐depth electronic structure analysis reveals that the bond order is more effective than the ionic radius to estimate potential barriers of Cu substitution in complex clinker system mainly because the latter underestimates the influence of electronic structure differences while the bond order directly measures the bonding structure related to interatomic charge transfer. [ABSTRACT FROM AUTHOR]

ABSTRACT A polyacrylonitrile fiber catalyst with high polar surface micro-environment (C-PANF-Na) was conveniently synthesized and characterized by elemental analysis, Fourier-transfer infrared spectroscopy, UV-vis spectroscopy, scanning electron microscopy, X-ray diffraction, and breaking strength test. The catalytic performance of the fiber was tested by Henry reaction and Gewald reaction in water and favorable results were obtained in terms of high yields, mild conditions, extensive applicability, superior catalytic recyclability, and renewability. It also has advantages of easy preparation, high functional degree, good stability in acid and base, high strength, and good flexibility, and so on. In addition, a high solvent selectivity phenomenon was found in this catalytic system and the reason was explained by proposing a high polar micro-environment effect. Furthermore, the fiber catalyst performed well in scaled-up experiment and flow chemistry experiment, which shows tremendous potential in industrial catalyst as an ideal material for packed bed. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45992. [ABSTRACT FROM AUTHOR]

Polyacrylonitrile fibers were functionalized with different amines to construct special tridimensional catalytic microenvironments at the surface. The polarity of the microenvironments at the surface of the fiber catalyst was tuned by changing the ratio of hydrophobic and hydrophilic amines. The catalytic performances of these microenvironments were examined for a cyanation reaction in water. Among these fiber catalysts with different microenvironments, the one modified with more hydrophobic benzylamine groups (PANBTF) shows much higher catalytic activity than that modified by hydrophilic ethanolamine groups. PANBTF can efficiently and rapidly catalyze the cyanation reaction of benzaldehyde and ethyl cyanoformate in water with a yield of 94 % at room temperature within 40 min. Moreover, a mechanism promoted by the hydrophobic microenvironment has been proposed to explain the high and specific catalytic activity of PANBTF. In addition, this fiber catalyst exhibited excellent recyclability and reusability (8 times) without further treatment, and it also performed well in flow-chemistry tests and scaled-up experiments, which indicated potential for the application of PANBTF in industrial production. [ABSTRACT FROM AUTHOR]

A novel solid acid catalyst (PANEAPF) is developed by immobilization of phosphoric acid on polyacrylonitrile fiber through covalent bonding. Various characterization techniques such as elemental analysis (EA), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), etc. are utilized to confirm the successful grafting and the stability of the fiber catalysts during application. PANEAPF shows high catalytic activity in the acetalization of aldehydes owing to the high utilization efficiency of its functionalized acid sites. In addition, the strong polarity micro-environment in the surface layers of PANEAPF make it highly suitable for catalytic application in both water and alcohol. Furthermore, the fiber catalyst can be applied to the acetalization of aldehydes in a continuous-flow process at room temperature, and shows excellent reactivity and superior recyclability (over 20 times). The many advantages of PANEAPF such as simple preparation, convenient regulation of acid amount, high durability, and eco-friendly process make it very attractive for fixed-bed reactors in the chemical industry. [ABSTRACT FROM AUTHOR]

A highly efficient catalytic system composed of a bifunctional polyacrylonitrile fiber (PANF-PA[BnBr]) and a metal chloride was employed to produce 5-hydroxymethylfurfural (HMF) from sucrose in mixed-aqueous systems. The promoter of PANF-PA[BnBr] incorporates protonic acid groups that promote the hydrolysis of the glycosidic bond to convert sucrose into glucose and fructose, and then catalyzes fructose dehydration to HMF, while the ammonium moiety may promote synergetically with the metal chloride the isomerization of glucose to fructose and transfer HMF from the aqueous to the organic phase. The detailed characterization by elemental analysis, FTIR spectroscopy, and SEM confirmed the rangeability of the fiber promoter during the modification and utilization processes. Excellent results in terms of high yield (72.8%) of HMF, superior recyclability (6 cycles) of the process, and effective scale-up and simple separation procedures of the catalytic system were obtained. Moreover, the prominent features (high strength, good flexibility, etc.) of the fibers are very attractive for fix-bed reactor. [ABSTRACT FROM AUTHOR]

A series of ionic liquids supported on polyacrylonitrile fibers (FSILs) served as 'release and catch' catalysts to mediate the Friedel-Crafts alkylation of indoles exclusively in water. Detailed characterization by elemental analysis, FTIR spectroscopy, and SEM confirmed that a significant amount of ionic liquid was immobilized on the surface layer of the fiber, and excellent results, in terms of the simple procedure, high yields (87-96 %), and superior catalytic recyclability (over 10 cycles), are reported for the metal and cosolvent-free synthesis of a wide variety of bis(indolyl)methanes at room temperature. The reason why the reaction catalyzed with FSILs only proceeded in water is explained, and a 'release and catch' catalytic mechanism is proposed. Moreover, the procedures can be scaled up efficiently, and the solvent can be recovered and reused without contamination. The prominent features of the fiber catalyst are very attractive for fixed-bed reactors in the chemical industry. [ABSTRACT FROM AUTHOR]

A new polyacrylonitrile fiber-supported Brønsted acid catalyst has been developed and verified to efficiently (high yield, 10 cycles) mediate Biginelli reactions in ethanol, Pechmann condensations in toluene, Friedel-Crafts alkylations of indoles in water and conversion of fructose in dimethyl sulfoxide (DMSO) and mixed-aqueous system. [ABSTRACT FROM AUTHOR]

(1− x) BaTiO3- x BiYO3 [(1− x) BT- x BY] polycrystalline ceramics were prepared by solid-state reaction method. The ceramics are in tetragonal phase when x ≤ 0.04, transform to pseudocubic at x ≥ 0.06, showing a classic ferroelectric to relaxor transition at x = 0.06, where the phase transition temperature was found to shift to higher temperature with increasing frequency. The dielectric permittivity peaks were analyzed by the modified Curie-Weiss law. Both parameters ΔTdiffuse and ΔTrelaxor were found to increase with increasing BY content, demonstrating a stronger relaxor characteristic. [ABSTRACT FROM AUTHOR]