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Trifluoromethyl (CF3) and other fluoroalkyl groups are of great significance in the fields of pharmaceutical chemistry and agricultural chemicals. Fluoroalkyl acids, especially trifluoroacetic acid (TFA) is considered the most ideal fluoroalkylation reagent due to its low cost and easy availability. However, the extremely high oxidation potential requirement of TFA limits its wide application. In recent years, since visible-light-induced fluoroalkylation through the ligand-to-metal charge transfer (LMCT) process can overcome the above limitations, it has become an effective synthetic tool for the construction of fluorinated compounds with complex molecules and structures. In this review, according to the classification of different metal catalysts, we summarize the trifluoromethylation and fluoroalkylation of olefins, heteroaromatics, and terminal alkynes in different metal catalytic systems and their corresponding reaction mechanisms. The photocatalytic fluoroalkylation via LMCT is believed to expedite the development of fluoro-containing drugs, and more novel fluoroalkylation methologies using this strategy will be disclosed. [ABSTRACT FROM AUTHOR]

Different types of natural K+ channels share similar core modules and cation permeability characteristics. In this study, we have developed novel artificial K+ channels by rebuilding the core modules of natural K+ channels in artificial systems. All the channels displayed high selectivity for K+ over Na+ and exhibited a selectivity sequence of K+≈Rb+ during the transport process, which is highly consistent with the cation permeability characteristics of natural K+ channels. More importantly, these artificial channels could be efficiently inserted into cell membranes and mediate the transmembrane transport of K+, disrupting the cellular K+ homeostasis and eventually triggering the apoptosis of cells. These findings demonstrate that, by rebuilding the core modules of natural K+ channels in artificial systems, the structures, transport behaviors, and physiological functions of natural K+ channels can be mimicked in synthetic channels. [ABSTRACT FROM AUTHOR]

Different types of natural K+ channels share similar core modules and cation permeability characteristics. In this study, we have developed novel artificial K+ channels by rebuilding the core modules of natural K+ channels in artificial systems. All the channels displayed high selectivity for K+ over Na+ and exhibited a selectivity sequence of K+≈Rb+ during the transport process, which is highly consistent with the cation permeability characteristics of natural K+ channels. More importantly, these artificial channels could be efficiently inserted into cell membranes and mediate the transmembrane transport of K+, disrupting the cellular K+ homeostasis and eventually triggering the apoptosis of cells. These findings demonstrate that, by rebuilding the core modules of natural K+ channels in artificial systems, the structures, transport behaviors, and physiological functions of natural K+ channels can be mimicked in synthetic channels. [ABSTRACT FROM AUTHOR]

There are many kinds of soil amendments that consist of different materials. The soil amendment is usually of benefit to plant health. However, the effects of the soil amendments on plant disease have rarely been compared and the involved mechanisms are largely unknown. In the present study, we investigated the influences of five contrasting soil amendments (i.e., potassium silicate (PS), calcium silicate (CS), biochar (BC), calcium silicate humic acid (SCHA), and bio-organic fertilizer (BOF)) on tomato bacterial wilt. In addition, we dissected the mechanism with high-throughput sequencing. The results showed that BC, SCHA, and BOF significantly reduced the incidence and delayed the disease, while BOF significantly reduced the incidence of bacterial wilt disease in the whole tomato growing period. In the early stage of the disease, BC, SCHA, and BOF significantly reduced the soil pH compared to CK. However, the contents of soil NH4+-N and NO3−-N were significantly increased. Some beneficial bacteria genera (Burkholderia, Mortierella, and Trichoderma) had a certain correlation with the incidence. Burkholderia and Mortierella were negatively associated with morbidity, but Trichoderma was positively associated with morbidity. Particularly, the Spearman correlation and the least partial squares path analysis indicated that Trichoderma was significantly positively correlated with the disease incidence, the soil physicochemical properties, and the numbers of soil pathogens (NSP) were significantly positively correlated with the number of root pathogens (NRP) and the physicochemical properties of plants were negatively correlated with the disease incidence. Moreover, BOF had better inhibitory effect on the occurrence of tomato bacterial wilt. Our results have implications for the better integrated management of tomato bacterial wilt. [ABSTRACT FROM AUTHOR]

Cytosine arabinoside (Ara-C) has been the standard therapeutic agent for myelodysplastic syndromes (MDS) and adult acute myeloid leukemia (AML) patients for decades. Considerable progress has been made in development of new treatments for MDS/AML patients, but drug resistance remains a major clinical problem. Apoptotic bodies (ABs), produced by late apoptotic cells, can enclose bioactive components that affect cell-cell interactions and disease progression. We isolated and identified drug-induced ABs from Ara-C-tolerance cells. Treatment of sensitive cells with Ara-C-induced ABs resulted in Ara-C-resistant phenotype. We further investigated components and functions of Ara-C-induced ABs. Proteomics analysis in combination with mass spectrometry revealed that Ara-C-induced ABs carried numerous RNA-binding proteins, notably including insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3). Delivery of AB-encapsulated IGF2BP3 promoted survival of recipient cells by activating PI3K-AKT and p42-44 MAPK pathways. High IGF2BP3 level in ABs from MDS/AML patient plasma was correlated with poor overall survival. Our findings demonstrate that AB-derived IGF2BP3 plays an essential role in acquired Ara-C resistance in MDS/AML patients, and is a potential therapeutic target for suppression of Ara-C resistance. [ABSTRACT FROM AUTHOR]

Mitogen-activated protein kinase (MAPK) pathways, such as the high-osmolarity glycerol mitogen-activated protein kinase (HOG) pathway, are evolutionarily conserved signaling modules responsible for transmitting environmental stress signals in eukaryotic organisms. Here, we identified the MAPK homologue in the HOG pathway of Coprinopsis cinerea, which was named CcSakA. Furthermore, during the development of the fruiting body, CcSakA was phosphorylated in the fast elongating apical part of the stipe, which meant that CcSakA was activated in the apical elongating stipe region of the fruiting body. The knockdown of CcSakA resulted in a shorter stipe of the fruiting body compared to the control strain, and the expression of phosphomimicking mutant CcSakA led to a longer stipe of the fruiting body compared to the control strain. The chitinase CcChiE1, which plays a key role during stipe elongation, was downregulated in the CcSakA knockdown strains and upregulated in the CcSakA phosphomimicking mutant strains. The results indicated that CcSakA participated in the elongation of stipes in the fruiting body development of C. cinerea by regulating the expression of CcChiE1. Analysis of the H2O2 concentration in different parts of the stipe showed that the oxidative stress in the elongating part of the stipe was higher than those in the non-elongating part. The results indicated that CcSakA of the HOG pathway may be activated by oxidative stress. Our results demonstrated that the HOG pathway transmits stress signals and regulates the expression of CcChiE1 during fruiting body development in C. cinerea. [ABSTRACT FROM AUTHOR]

The article below describes a simple methodology to prepare cost-effective biodegradable poly(ester urethane)s (PEUs) with ordered hard segments (OHS) for medical application as long-term implants. A low-cost diurethane diol (1,4-butanediol-hexanediisocyanate-1,4-butanediol, BHB) was first designed and synthesized. Consequently, the BHB was employed as a chain extender to react with NCO-terminated poly(ε-caprolactone) to obtain PEUs. The molecular structural formats for BHB and PEUs were defined through NMR, FT-IR, and MS together with GPC, while the influence of OHS content on physical/chemical features for casted PEU films was investigated. The introduction of OHS could contribute to forming denser hydrogen-bonds, and consequently produce a compact network structure, resulting in great tensile capacity, low water absorption, and slow hydrolytic degradation rate by PEU films. PEU-2.0 films, which possessed the highest OHS content within PEUs, exhibited 40.6 MPa tensile strength together with 477% elongation at break, 4.3 wt % equilibrium water absorption and only 29.5% weight loss post-12 months' degradation. In addition, cytotoxicity analysis of film extracts indicated that the cell viability of all PEUs containing OHS exceeded 75%, indicating good cytocompatibility. Due to outstanding tensile features, high biostability, nontoxic and absorbable degradation products and acceptable cytocompatibility, the cost-effective materials exhibited promising applications in the field of long-term implants. [ABSTRACT FROM AUTHOR]

Camptothecin (CPT) is a potent and broad-spectrum anti-tumor drug, but its clinical application is limited due to its poor water solubility, toxicity, and low drug-loading potential. Different delivery protocols have been developed to optimize the therapeutic effects of CPT. In this study, CPT was modified into a dimer (CPT-Mal-CPT), in which two CPT molecules are connected by a reduction-responsive maleimide thioether bond. Moreover, biocompatible methoxy poly(ethylene glycol)-b-poly(ε-caprolactone) (mPEG–PCL)-loaded CPT-Mal-CPT nanoparticles were prepared to overcome the limits of CPT application. The power X-ray diffractometer (PXRD) results indicate low crystallinity and amorphous nature of CPT-Mal-CPT. The CPT-Mal-CPT-loaded micelles showed a drug-loading content of 9.6% and a drug-loading efficiency of 56%. In addition, dimeric CPT micelles showed reduction-responsive release under 10-mM dithiothreitol (DTT), while negligible CPT release was detected in the absence of DTT. MTT assay indicated that cytotoxicity of dimeric CPT micelle was similar to free CPT. [ABSTRACT FROM AUTHOR]

We synthesized BiOI(001)/cocatalysts composites, selective deposition of cocatalysts were demonstrated to be an effective method to improve their photocatalytic performance. Ag nanoparticles were grown on the surfaces of the pre-synthesized BiOI(001) nanosheets through a photodeposited process. The work demonstrates that the as-synthesized sample is a promising photocatalyst for the treatment of MO. The enhanced photocatalytic activity is attributed to the charge transfer from BiOI(001) to the attached Ag nanoparticles. [ABSTRACT FROM AUTHOR]

This paper investigates the construction of BiOCl with different dominant exposed facets and Ag/BiOCl. And their application as photo-catalysts was also evaluated by photodegradation of Rhodamine B (RhB). The synthesized photocatalysts were characterized by XRD, SEM, and N2–adsorption–desorption. This excellent photocatalytic activity was attributed to the exposure of (001) facet, which facilitated the separation of photogenerated electrons and holes. It reveals that the Ag depositing on BiOCl could result into enhanced photocatalytic activities compared with that of the pure BiOCl. The photocatalytic mechanisms were analyzed by active species trapping experiments, indicating that the h+ plays a major role on photocatalytic degradation reaction of RhB with Bi-H2 and Ag/BiOCl. [ABSTRACT FROM AUTHOR]

By interfacial coupling effect, the reduced graphene oxide (rGO) was constructed on (010) facet of BiVO4, which is a characteristic of the dominant separation of photogenerated electrons. The prepared samples were characterized by X-ray diffractometry and Raman spectra, which indicating that the added rGO plays an important role in regulating of V–O bond. By the X-ray photoelectron spectroscopy, it was found that the valence band value of BGO180 is increased compared with BiVO4, suggesting that there is an effective coupling present between rGO and BiVO4. Under simulated sunlight, the photocatalytic properties of BiVO4/rGO nanocomposite are evaluated by the O2 evolution. The carrier transfer effect between BiVO4 and newly formed coupling layer (BiVO4 and rGO) explains the excellent photoactivity of nanocomposite. [ABSTRACT FROM AUTHOR]

In this work, Sr0.5Ba0.5TiO3 (SBT) thin films with different thickness were prepared on a Pt/SiO2/Si substrate by sol-gel process. The microstructures of SBT thin films were examined by X-ray diffraction(XRD) and trans- mission electron microscopy (TEM). Morphologies of samples were characterized by field-emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM). The influences of thickness on the microstructure and dielectric properties of SBT thin films were also studied. It is found that tetragonal perovskite crystal grains existed in SBT thin films. The results indicated that the optimum thickness is 450 nm for SBT thin films. [ABSTRACT FROM AUTHOR]

The unique reactivity and synthetic applications of oxime acetate derivatives with N, O and S substituents at the α-position are disclosed for the first time, which leads to 2-substituted fulleropyrrolidines and mono- and disubstituted 1-fulleropyrrolines via copper-catalyzed redox-neutral N-heteroannulation reactions with C60. This transformation is operationally simple and has a broad substrate scope and good functional group tolerance. Theoretical calculations at the level of B3LYP/6-31G(d) were performed to elucidate the chemoselectivity of the reaction. [ABSTRACT FROM AUTHOR]

A short and efficient stereoselective synthesis of a styryllactone (−)-isoaltholactone has been achieved in seven steps and 33% overall yield, starting from the readily available carbohydrate D-mannose. The key steps of our synthesis involve intramolecular tetrahydrofuran cyclization and one-pot acetonide deprotection-lactonization. [ABSTRACT FROM AUTHOR]

Series of α-mono-fluorinated acetoacetamides were synthesized under mild condition with industrialized Selectfluor as the F+ source in PEG-400. The approach avoided the use of base or metal catalyst, and most of cases proceeded in nearly quantitative conversions regardless of the electronic nature of the diversity substituent. [ABSTRACT FROM AUTHOR]

Rice sheath blight, a fungal disease caused by Rhizoctonia solani, seriously threatens rice production. Some of the volatile organic compounds (VOCs) produced by microbes are inhibitory to the growth of the plant pathogen, and hence may have the potential as environmentally friendly antifungal substances. However, information on the inhibitory effect of VOCs released by rice rhizosphere bacteria on R. solani is scarce. In this study, bacteria from the rice rhizosphere capable of inhibiting the growth of R. solani via releasing VOCs were screened using a double Petri dish assay. Headspace solid phase microextraction and gas chromatography mass spectrometry (GC/MS) were used to identify and quantify the VOCs. The contributions of VOCs to the inhibition of the growth of R. solani were estimated by constructing a random forest model, and were verified using pure compounds. Nine strains (i.e., Pseudomonas sp. No. 3, Enterobacter sp. No. 26, Enterobacter sp. No. 34, Pseudomonas sp. No. 35, Ralstonia sp. No. 50, Bacillus sp. No. 62, Arthrobacter sp. No. 146, Brevibacillus sp. No. 2–18, and Paenisporosarcina sp. No. 2–60) showed various inhibition on R. solani growth via VOCs. The inhibitory effect ranged from 7.84% to 100%, with Ralstonia sp. No. 50 completely inhibiting the growth of R. solani. Five VOCs (i.e., benzoic acid ethyl ester, 3-methyl-butanoic acid, 2-ethyl-1-hexanol, 3-methyl-1-butanol, and 6-methyl-5-hepten-2-one) identified by random forest model were confirmed to be toxic to R. solani when applied as a pure chemical compound. In particular, benzoic acid ethyl ester, 3-methyl-butanoic acid, and 2-ethyl-1-hexanol were lethal to R. solani. In summary, the rice rhizosphere bacteria (Ralstonia sp. No. 50) and VOCs (benzoic acid ethyl ester, 3-methyl-butanoic acid, and 2-ethyl-1-hexanol) showed potential to be used as new resources for biological control of rice sheath blight. [ABSTRACT FROM AUTHOR]

Miscible and near-miscible flooding are used to improve the performance of carbon-dioxide-enhanced oil recovery in heterogeneous porous media. However, knowledge of the effects of heterogeneous pore structure on CO2/oil flow behavior under these two flooding conditions is insufficient. In this study, we construct pore-scale CO2/oil flooding models for various flooding methods and comparatively analyze CO2/oil flow behavior and oil recovery efficiency in heterogeneous porous media. The simulation results indicate that compared to immiscible flooding, near-miscible flooding can increase the CO2 sweep area to some extent, but it is still inefficient to displace oil in small pore throats. For miscible flooding, although CO2 still preferentially displaces oil through big throats, it may subsequently invade small pore throats. In order to substantially increase oil recovery efficiency, miscible flooding is the priority choice; however, the increase of CO2 diffusivity has little effect on oil recovery enhancement. For immiscible and near-miscible flooding, CO2 injection velocity needs to be optimized. High CO2 injection velocity can speed up the oil recovery process while maintaining equivalent oil recovery efficiency for immiscible flooding, and low CO2 injection velocity may be beneficial to further enhancing oil recovery efficiency under near-miscible conditions. [ABSTRACT FROM AUTHOR]

The article "BiVO4(010)/rGO Nanocomposite and Its Photocatalysis Application", written by Lianwei Shan, Jingjing Bi, Changhui Lu and Yanwei Xiao, was originally published electronically on the publisher's internet portal (currently SpringerLink) on 5 October 2018 with open access. With the author(s)' decision to step back from Open Choice, the copyright of the article changed on November 2018 to © Springer Science + Business Media, LLC, part of Springer Nature 2018 and the article is forthwith distributed under the terms of copyright. [ABSTRACT FROM AUTHOR]

In order to have an insight into the internal electric field (IEF) of BiOCl(001), we design a novel wide-spectrum responsive BiOI(010)/BiOCl(001) heterojunction composite by a facile method. The system could shield the photocatalysis of BiOCl(001) under visible light due to its large Eg (3.41 eV), thus specifying role of the BiOCl(001) in BiOI(010)/BiOCl(001). The XRD and TEM results show that the composites exhibit a coexistence of both tetragonal BiOI(010) and BiOCl(001) phases. The as-prepared BiOI(010)/BiOCl(001) samples exhibit higher BET surface area than those of BiOI(010) and BiOCl(001). The UV, visible, and simulated sunlight photocatalytic activities of composites for methyl orange (MO) were greatly enhanced compared to either pure BiOI(010) or BiOCl(001). Especially, under the visible light, an enhancement of photocatalytic activity (MO, acid fuchsin) was found for BiOI(010)/BiOCl(001), suggesting an IEF of BiOCl(001) plays a key role on the photo-generated carrier separation of BiOI(010). Specifying the IEF role of BiOCl(001) in BiOI(010)/BiOCl(001) is expected to inspire the further exploration, developing efficient photocatalysts with potential applications. [ABSTRACT FROM AUTHOR]