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Dithiocarbamate (DTC) was synthesized using tetraethylenepentamine (TEPA) and carbon disulfide as raw materials. The product was characterized by FTIR and its chelating performance of removing lead ion in water was evaluated. The results are shown as follows. Characterization results from the FTIR spectra suggest the target product DTC has been successfully synthesized. The efficiency of removing lead ion or degree of removal increases with removing time, pH value, and DTC dosage, respectively, and then keeps almost unchanged when continuously increasing each of these factors. On the other hand, the degree of removal decreases with the initial concentration of lead ion. Meanwhile, the amount of sorption decreases with the DTC dosage and increases with the initial concentration of lead ion. 99.9% of degree of removal is obtained under a condition including 6 of pH, 220 min of removing time, 3.2 g L–1 of DTC dosage, and 40 mg L–1 of initial ion concentration. The relationship between the amount of sorption and equilibrium lead concentration is in good accordance with the isothermal equation of Langmuir model while it is in worse accordance with that of Freundlich model. It suggests that the chelating process is a monolayer coverage resulting from the chemical combination by the DTC groups, namely the chelating active sites. What’s more, the product of chelating reaction between DTC and Pb2+ ion is more stable and insoluble in water so that it can be easily separated from the solution. Accordingly, the synthesized DTC in this work is a good reagent for removing Pb2+ ion in wastewaters and will be widely used in the field of environment protection.

Purpose: To investigate the neuroprotective effect of lidocaine in Neuro2A cells Methods: Differentiated N2a cells were used in this study. Cell viability and neuroprotection were assessed using dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and trypan blue assays, while Bax/Bcl-2 expression was assayed by western blotting. Mitochondrial membrane potential, reactive oxygen species and calcium levels were measured using flow cytometry. Results: Lidocaine protected differentiated N2a cells against cadmium-induced toxicity, and also attenuated cadmium toxicity-induced changes in mitochondrial membrane potential (MMP), reactive oxygen species (ROS) and calcium (Ca2+) levels. Furthermore, Bax/Bcl-2 ratio, which was disrupted by cadmium, and cadmium-induced apoptosis, were reversed by lidocaine. Conclusion: Lidocaine protects differentiated N2a cells against cadmium-induced toxicity by reversing apoptosis. Thus, lidocaine is a potential neuroprotective agent.

Inhibiting the recombination of photo-generated charge carriers remains one of the important challenges for photocatalytic materials nowadays. For this, we reported a series of novel bismuth layered structure ferroelectrics: M0.5Bi2.5Nb2O9 (M = Li, Na, K) nanosheets prepared by one-step hydrothermal method. The fabricated nanosheets with average thickness size of about 32 nm (Li0.5Bi2.5Nb2O9), 45 nm (Na0.5Bi2.5Nb2O9), 108 nm (K0.5Bi2.5Nb2O9) possess excellent photodegradation performance to various organic dye pollutants with high concentration of 20 mg/L [Rhodamine B (RhB), methyl orange (MO) etc.]. Interestingly, the degradation rate constants of RhB and MO can be further improved by polarization-induced charge separation under ultrasonic-assisted illumination condition, compared with those of light illumination alone, and increased by about 2.5 times for Na0.5Bi2.5Nb2O9 nanosheets. These findings make bismuth layered ferroelectric materials have a potential application in wastewater treatment as a kind of important photocatalysis.

Herein, we report a method of fabricating strong and thermosensitive double network (T-DN) poly(N-isopropyl acrylamide) (PNIPAM)-based hydrogels, i.e. rigid and brittle poly(2-acrylamido-2-methylpropanesulfonic acid sodium salt) (PNaAMPS) as the first and soft and ductile poly(N-isopropyl acrylamide-co-acrylamide) (P(NIPAM-co-AAm)) as the second interpenetrating each other. In particular, NIPAM was deliberately integrated into the double network as an adjustor of elastic modulus and hydrophilicity, besides thermosensitivity. Such double network construction strategy resulted in PNaAMPS/P(NIPAM-co-AAm) T-DN hydrogels of excellent mechanical properties (0.83-1.37 MPa) and desirable temperature-dependent swellabilities. Besides, T-DN hydrogels with various NIPAM contents exhibited good biocompatibility with high cell survival rates around normal body temperatures. Furthermore, crystal violet (CV) could be readily loaded to impart antibacterial functionality to the T-DN hydrogels against E. coli. The double network construction strategy could be adapted to fabricating high-strength antibacterial hydrogels for a broad range of biomedical applications.

Anthocyanidins are flavonoids in plants with various biological activities and health-promoting effects. As plant-derived safe pigments, anthocyanidins have important economic values and broad applications. Dihydroflavonol 4-reductase (DFR) can catalyze dihydroflavonols into leucoanthocyanidins, which can turn into anthocyanidins through thermal incubation in n-butanol-HCl. However, studies on the enzymatic synthesis of anthocyanidins in vitro using recyclable nano-carrier immobilized enzymes have scarcely been seen until now. Here, we prepared magnetic Fe3O4–PEI-pMaltose nanoparticles and the recombinant DFR fusion enzyme with a maltose binding protein (MBP) tag. The DFR enzyme was immobilized on the Fe3O4–PEI-pMaltose nanoparticles based on the affinity adsorption under the optimum conditions of an enzyme/support ratio of 125 mg g−1, 20 °C, a pH of 6.5 and 25 min immobilization time. The sizes, morphologies, structures, and magnetic properties of the magnetic Fe3O4–PEI-pMaltose nanoparticles and the Fe3O4–PEI-pMaltose-immobilized DFR enzyme were characterized. The products from dihydroquercetin/dihydromyricetin catalyzed by the immobilized DFR enzyme or free DFR enzyme were both confirmed as cyanidin/delphinidin. Compared with the free DFR enzyme, the optimum reaction temperature and pH of the immobilized DFR enzyme were increased. The immobilized DFR enzyme possessed improved thermal and storage stabilities and enhanced tolerance to high pH conditions, and reduced the inhibitory effects of metal ions and organic solvents on the enzymatic activities. After four times repeated use, the activity of immobilized DFR remained above 85%.

A highly stereoselective cascade Michael/alkylation process has been established to construct 2-trifluoromethylated and 2-difluoromethylated dihydrofurans from readily available starting materials. In the presence of a bifunctional squaramide, the annulation approach proceeded smoothly to afford the desired fluorinated dihydrofurans in 59–99% isolated yields with 82–96% ee and 8 : 1–>20 : 1 dr. This catalytic strategy was well compatible with various structurally distinct β,β-bromonitrostyrenes and fluorinated acetoacetates. Profound synthetic manipulation could be performed on the resulting products.

Optimised drug delivery systems with low toxicity and high efficacy for suppressing cancer cells are urgently needed. In this study, a quinolone derivative-based organoplatinum(II) supramolecular coordination complex (SCC) was synthesised by [2 + 2] coordination-driven self-assembly. Using this molecular design, synergistic chemotherapeutic effects were achieved by combining the anticancer agent platinum acceptor and quinolone derivative at a fixed ratio. Importantly, the well-defined rhomboidal shape and size of the SCC metallacycle self-assembled into nanoparticles with an average diameter of 38 nm in aqueous solution, conferring improved passive targeting and internalisation abilities towards tumour cells via the enhanced permeability and retention effect. In vitro evaluation with HepG2 cells showed that integration of the quinolone derivative and organoplatinum(II) acceptor improved antitumor activity compared with each independent component. These properties reveal the potential of Pt(II)-based SCCs for use in antitumor applications as a supramolecular chemotherapy self-delivery platform. A Pt(II) metallacycle-based supramolecular self-delivery nanocarrier platform through coordination-driven self-assembly of a dipyridine-functionalised quinolone derivative donor (QD) and 60° Pt (II) acceptor (PhenPt) was successfully constructed. This nanocarrier considerably enhanced the internalisation and anticancer efficacy, as shown by in vitro studies.

The thaumasite sulfate attack (TSA) on tunnel concrete structure has been reported increasingly in the past decades. Previous investigations on the formation of thaumasite were focused on identifying the deterioration products and reaction mechanisms, while the occurrence time of TSA on tunnel concrete structures was not reported. A highway tunnel exposed to TSA was reported in the present study. The development of tunnel diseases and results of experimental tests conducted in the tunnel and in the laboratory were analyzed to investigate the occurrence time of TSA on concrete. Results revealed that the thaumasite was formed in a range of 18 to 36 months after the construction of Dugongling tunnel. The preconditions for the formation of thaumasite on tunnel concrete structures are available in Shanxi Province, China, due to the special conditions of stratum lithology and climate. The compositions of corrosion products of lining concrete under TSA varied for site studies and for laboratory tests. Site investigations on TSA on tunnel lining concrete should be paid more attention in further research.

After tethering sodium 2-mercaptoethanesulfonate (MTS) to the bromomethylated poly(arylene ether ketone) precursor, a novel clustered sulfonated poly(arylene ether ketone) containing flexible sulfoalkyl groups (MTSPAEK) was prepared and used as polymer electrolyte membrane for application in DMFCs. The chemical structure and the degree of grafting of MTSPAEK copolymers were identified by 1H NMR spectra. The resulted MTSPAEK copolymers exhibited excellent thermal stability (Td5% > 259 °C) and good mechanical properties (tensile strength at break > 52 MPa). Compared to conventional sulfonated aromatic hydrocarbon polymers, MTSPAEK membranes displayed enhanced oxidative stability in Fenton's reagent owing to the elimination of free radicals by the sulfide groups located on the polymer side chains. Especially, MTSPAEK-2.10 with the highest content of flexible sulfoalkyl groups exhibited a highest proton conductivity of 0.181 S cm−1 at 80 °C. It could be attributed to the obvious hydrophilic/hydrophobic phase-separated structure within the membrane, which was confirmed by AFM images. Moreover, MTSPAEK-2.10 membrane performed a peak power density of 70 mW cm−2 in DMFC when feeding with 2 M methanol at 80 °C, which was comparable to the performance of recast Nafion as reported. Therefore, the combination of good thermal stability and mechanical properties, good oxidative stability, and good methanol barrier performance of MTSPAEK membranes indicated that they have potential to be alternative materials for PEMs in DMFCs.

Acrylic acid-modified polyhedral oligomeric silsesquioxane (AC-POSS) was synthesized by the reaction between the amine groups in polyhedral oligomeric silsesquioxane (POSS) and acrylic acid, which could dissolve in water and can be easily purified. Free-radical copolymerization was applied to synthesize azobenzene liquid crystalline polymer silsesquioxane (LCP-POSS) with different proportions of AC-POSS and liquid crystalline monomers. The trans-isomers of azobenzene moieties in LCP-POSS were gradually transformed to cis-isomers with increasing ultraviolet irradiation time. The photoisomerization reaction of liquid crystalline polymer (LCP) and LCP-POSS showed the first-order dynamic reaction. Compared with the LCP, the photoisomerization rate constant of LCP-POSS was decreased due to the space steric hindrance of the POSS as a rigid segment. The phase transition temperature of liquid crystalline in LCP-POSS increased with increasing POSS content, and the liquid crystalline texture in LCP-POSS became smaller under the polarized light. With further increasing the POSS content (>50 wt%) in LCP-POSS, the ordered structure of the liquid crystalline phase was gradually affected, resulting in one-way liquid crystal (LC) phase behavior. The synthesized LCP-POSS has LC properties, light-responsive properties, and thermal stability. When the POSS is introduced into the LC material, the phase state of the LC material will become more abundant and the LC phase will become more stable. The significance of this study is to develop and extend its applications as stimuli-responsive materials and devices.

To enhance the nonlinear optical properties of graphene oxide in organic solvent and polymeric matrix, lutecium phthalocyanines (LuPc) and hyperbranched lutecium phthalocyanines (HBLuPc) have been grafted on the surface of graphene oxide, respectively. After the surficial modification, the electron transfer process between phthalocyanines and graphene oxide has been also facilitated, resulting in significant fluorescence quenching. Given the combination of nonlinear scattering, two-photon absorption with reverse saturable absorption and the photo-induced electron or energy transfer from the electron donor (phthalocyanine moiety) to the acceptor (graphene oxide), stronger nonlinear optical properties can be realized based on graphene oxide hybrids compared with graphene oxide and phthalocyanines. Furthermore, graphene oxide hybrid modified by hyperbranched lutecium phthalocyanines exhibits the best optical limiting response and the highest nonlinear extinction coefficient at 532 nm in both organic solvent and polymeric matrix. Interestingly, we also find that it could exhibit better optical limiting properties than those possessed by pure phthalocyanine at 1064 nm.

Chitosan (CS) has become a favorable choice for synthesizing hydrogels due to its hydrophilic and biocompatible nature. However, achieving robust CS-based hydrogels remains challenging. Herein, we propose a multiple mechanisms-based network design for mechanical enhancement in CS-based double-network (DN) composite hydrogels. In the DN composite gels, graphene oxide-filled CS-based network serves as the first network and polyacrylamide network is the second network. The multi-structure of the first network enhances its energy dissipation capacity; when combining with the second network to form DN structure, the coupling effect between the multiple mechanisms-based networks allows for much more energy dissipation, enabling synergistic enhancement in mechanical properties of the DN composite gels. By regulating the mechanics, we further explore the role of the individual networks. The results indicate that both the individual networks are essential: The first network primarily contributes to the energy dissipation, while the second network plays a role to the synergistic enhancement in the DN composite gels. This work provides an effective reinforcing strategy for CS-based composite hydrogels.

To assess the efficacy and safety of the commonly used urate-lowering therapies (ULTs): febuxostat, allopurinol, and lesinurad in hyperuricemic patients with gout.We included all randomized controlled trials (RCTs) that compared ULTs with placebo or head to head. The primary efficacy endpoint was the proportion of subjects achieving the target serum urate (SU) level at month 6. Safety outcomes included total adverse events (AEs), serious AEs, withdrawals due to AEs, and AEs per organ system. A Bayesian network model was used to compare all ULTs with placebo and among themselves.Fifteen RCTs were included for the analysis, in which 7968 patients were randomly assigned to take either placebo or one of 11 ULTs: allopurinol, febuxostat 40/80/120/240 mg/day, lesinurad 400 mg/day, lesinurad 200/400/600 mg/day plus allopurinol, and lesinurad 200/400 mg/day plus febuxostat. All ULTs were effective in achieving the target SU level at month 6 compared with placebo (ORs between 26.81 and 1928). Febuxostat 80/120/240 mg/day was superior to allopurinol and well tolerated for urate reduction. And as febuxostat dosage increased, more patients achieved the target SU level. Furthermore, the lesinurad combination with xanthine oxidase inhibitor (XOI) groups had a higher proportion of patients achieving the target SU level than the febuxostat 40 mg/day group (ORs between 2.89 and 9.17), the allopurinol group (ORs between 3.56 and 11.27), or the lesinurad 400 mg/day monotherapy group (ORs between 12.30 and 39.17) but might have a high risk of AEs.All ULTs are effective in achieving the target SU level compared with placebo in hyperuricemic patients with gout. Lesinurad in combination with febuxostat or allopurinol is effective in urate lowering, especially for patients with inadequate response to XOI monotherapy. Key Points • All urate-lowering therapies (ULTs) were effective in achieving the target serum urate (SU) level at month 6 compared with placebo in hyperuricemic patients with gout. • Febuxostat 80/120/240 mg/day was superior to allopurinol and well tolerated for urate reduction. And as febuxostat dosage increased, more patients achieved the target SU level. • Lesinurad in combination with febuxostat or allopurinol was effective in urate lowering, especially for patients with inadequate response to xanthine oxidase inhibitor monotherapy, but might have a high risk of AEs.

Isocyanates are widely applied in the fields of materials science, drug discovery and chemical industry processes. Palladium-catalyzed carbonylation of azides with carbon monoxide (CO) is reported as a powerful method for simple and efficient access to isocyanates, which are important precursors for preparing structurally meaningful urea, carbamate and amidine derivatives. In this account, we provide an overview on the synthesis of isocyanates and their subsequent reactions to obtain diverse nucleophilic addition products. In addition, with particular emphasis on our mechanistic studies of the Pd-catalyzed carbonylation process, we outline the identification of the actual catalytic species, the possible intermediates and some key factors in the catalytic cycle.1 Introduction2 Palladium-Catalyzed Reaction of Azides with CO and Subsequent Nucleophilic Additions3 Mechanistic Studies on the Palladium-Catalyzed Reaction of Azides with CO3.1 Studies on the Actual Catalytic Species and the Key Intermediates in the Activation and Carbonylation of Acyl Azides3.2 Study of the Sulfonylurea Product Self-Catalyzed Carbonylation of Sulfonyl Azides3.3 Study of the Actual Catalytic Pattern of the Pd/C Catalyst4 Conclusion

To investigate the impacts of the widely used chiral herbicide fenoxaprop-ethyl (FE) on aquatic organisms, the enrichment, metabolism, acute toxicity, and oxidative stress of fenoxaprop-ethyl and its main metabolites fenoxaprop (FA), ethyl-2-(4-hydroxyphenoxy)propanoate (EHPP), 2-(4-hydroxyphenoxy)propanoic acid (HPPA), and 6-chloro-2,3-dihydrobenzoxazol-2-one (CDHB) in zebrafish were studied. The enantioselectivity of fenoxaprop-ethyl and its chiral metabolites was also determined. Fenoxaprop-ethyl quickly degraded in zebrafish by aquatic exposure. FA, HPPA, and CDHB were the main metabolites that were enriched in the zebrafish. In the metabolism experiment, the half-lives of the metabolites were 0.92-1.72 days in zebrafish. The R-enantiomers of FA and HPPA were preferentially enriched and metabolized with enantiomeric fractions (EFs) of 0.65-0.85. According to the 96-h acute toxicity, FA, HPPA, EHPP, and CDHB were less toxic to zebrafish than FE, following the order of FE > CDHB > EHPP > FA > HPPA. The S-enantiomers of FE, FA, CDHB, and EHPP were more toxic than the R-enantiomers. FE and its metabolites could significantly increase catalase (CAT) and superoxide dismutase (SOD) activity and the malondialdehyde (MDA) content in gill and liver tissues, indicating their oxidative stress, and these effects were also enantioselective. This work could supply more information for evaluating the risks of fenoxaprop-ethyl on aquatic organisms concerning their metabolites and enantiomers.

The phosphine-catalyzed cascade Michael addition/[4+2] cycloaddition reaction of tetrahydrobenzofuranone-derived allenoates and 2-arylidene-1,3-indanediones has been reported, affording spirocyclic 1,3-indanedione derivatives in moderate to high yields with moderate to good diastereoselectivities. A scaled-up reaction worked well under mild conditions, and a plausible mechanism is proposed.

In this work, a series of oil soluble diblock copolymers poly(methyl methacrylate)-b-poly[2-(dimethylamino)ethyl methacrylate] (PMMAm-b-PDEAEMAn; where m is fixed at 49 and n is varied from 3 to 12) are synthesized using a reversible addition-fragmentation chain transfer RAFT method. The copolymers exhibit pH-dependant interfacial activities and behave as macromolecular surfactants under strong acidic conditions. The coassembly behavior and kinetics of cellulose nanocrystals (CNCs) and the copolymer at the water/toluene interface is probed by tracking the dynamic interfacial tension using pendant drop tensiometry. At low pH such as 2 and 3, the film that CNCs coassemble with the copolymer at the oil/water interface can stabilize the pendant drop from dripping down. At a higher pH value, CNCs enhance the interfacial activity of the copolymer through interfacial tension measured and emulsions test. When investigating the coassembly kinetics, it is found that the interfacial protonation reaction of the copolymer and absorbing at the oil/water interface is the rate-determining step and electrostatic binding with CNCs is a much faster process. Besides, the interfacial activity of PMMAm-b-PDEAEMAn is enhanced as n increases and the interfacial coassembly with CNCs is accelerated. A nanoparticle film can be formed because of the coassembly behavior of CNCs and diblock copolymers at the oil/water interface and can stabilize the liquid/liquid interface and endow the interface elastic property. Based on this property, liquid tubule can be generated through injecting CNC aqueous dispersion to copolymer toluene solution. This formation of liquid tubule opens a new platform for the additive manufacturing technique of three-dimensional printing of liquid constructs.

Hypothesis Novel Pickering emulsions stabilized by self-assembled nano-objects of amphiphilic copolymers are attractive in many applications. However, it is not clear to what extent those nano-objects could stay at the oil/water interface. Owing to the twisted intramolecular charge transfer state (TICT) property of Nile red, the distinguishable fluorescent characteristics of Nile red dissolved in n-dodecane and solubilized in copolymer micelles benefit the investigation of the oil/water interfacial nature of Pickering emulsions in situ. Experiments Two amphiphilic diblock copolymers PNMP53-b-PFMA5 and PNMP53-b-PFMA10 named poly(N-(2-methacryloylxyethyl) pyrrolidone)-block-poly(2-(perfluorooctyl) ethyl methacrylate) were synthesized, they can form spherical and wormlike micelles in water spontaneously, respectively. Oil in water (O/W) emulsions were generally produced at different conditions by employing these copolymer micelles as emulsifiers. The size and morphology of prepared emulsions were studied by light scattering and microscope techniques in detail. Moreover, the effect of emulsification conditions on the interfacial morphology evolution of prepared emulsions were characterized systematically in situ by the proposed method based on the confocal laser scanning microscopy (CLSM) measurements. Findings We clarified the progressive transition from Pickering emulsions to classic emulsions through the sustained changes of emulsification conditions by the developed CLSM method, in which block copolymer monomers and their assemblies were played as emulsifiers to stabilize emulsion droplets synergistically. Generally speaking, Pickering emulsions were produced in the presence of sufficient micelles at low emulsification shear rates. Otherwise, common emulsions stabilized by block copolymer monomers would be formed.

The design of efficient semiconductor oxide materials with heterojunction nanostructures for photocatalysis holds great promise in the fields of clean energy conversion and storage. Current synthesis methods for heterojunction composites readily result in phase separation and uncontrollable products, and require harsh preparation methods. In order to address these issues and optimize the microstructure of the heterojunction photocatalyst, controllable synthesis and differences in the porosity are introduced. For the first time, we synthesized a mesoporous Ga2O3/GaOOH heterojunction composite for photocatalytic hydrogen generation using an ingenious ultraviolet-induced Ostwald ripening strategy. Furthermore, the detailed formation mechanism and energy band structure of the as-synthesized material were elucidated. The intimate contact of the heterojunction, refined mesoporous structure and large specific surface area of the mesoporous Ga2O3/GaOOH heterojunction composite endow the material with efficient charge separation and transfer and significantly exposed junction active sites, which results in an enhanced photocatalytic hydrogen generation performance. This study opens up new horizons in the construction of mesoporous metal oxide heterojunction composites.

Curcumin (CM) is a natural polyphenolic compound with multiple biomedical functions. However, clinical applications face more challenges due to its low dissolution rate and poor bioavailability. Mi...

Background Shunxinzufang decoction is tutors, empirical formula and has been used in Chinese patients of HFpEF for several years. The aim of this study was to make into sustained release granules and select the best formula for the preparation of Shunxin sustained release granules and to evaluate its in vivo and in vitro drug release behavior. Methods Response surface methodology and Center composite design were applied to screen the optimal formula of Shunxin sustained release granules. HPLC was used to detect indicative ingredients—paeoniflorin, calycosin-7-glucoside and ferulic acid in Shunxin sustained release granules. The in vitro sustained release character of indicative ingredients was investigated in simulated digestive fluids. In-vivo process of active components was studied through pharmacokinetics. Results The optimal formula of Shunxin sustained release granules consisted of 35% shunxinzufang extract and 65% HPMC/starch (HPMC/starch ratio = 2:1). Three indicative components can be separated well under selected HPLC conditions. Compared with Shunxinzufang extract, the active components of Shunxin sustained release granules have obvious sustained-release character and improved bioavailability. Conclusion Shunxin sustained release granules has obvious sustained-release character and improved bioavailability.

The use of glycidyl methacrylate (GMA) and acrylic acid (AAc) as grafting monomers to improve the mechanical properties, particularly tensile strength, of recycled polyethylene (R-PE) is re...

Recently, conductive M-Nb-O composites have gained much attention as a novel lithium ion storage anode material. However, the conductivity and rate performance of M-Nb-O composites still need to be further enhanced. Herein, we have designed a facile strategy to prepare ZnNb2O6/N-doped carbon (ZnNb2O6/NC) which is derived from Nb2O5@zeolitic imidazole frameworks precursor. The ZnNb2O6/NC exhibits advanced energy storage properties including high initial capacity (673 mA h g−1 at 100 mA g−1), superior reversible specific capacity (412.6 mA h g−1 until 100 cycles at 100 mA g−1), long-term cyclic stability and excellent rate capability (470.5 mA h g−1 after 800 cycles at a relatively high current density of 2 A g−1).

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the authors and the Editor-in-Chief as the validity of the data cannot be guaranteed. The journal was initially contacted by the corresponding author to report that, when the authors verified post publication PTEN as their former target of miR-140-3p, they found that treatment with miR-140-3p or miR-155-5p antagomir increased PTEN protein levels in patient-derived chordoma cells without having a significant effect on the malignancy of the tumor cells. The journal further requested the author to provide more information about their post publication findings with regard to this article. However, the author was not able to fulfil this request.

Spirocyclic tetramic acids are widely used in controlling phytophagous mite species throughout the world. the data set is incomplete and provides insufficient evidence for drawing the same conclusion for fish. To fill the gap whether these acaricides alter lipid metabolism on vertebrates, zebrafish embryos exposed to a series concentration of pesticides, the developmental effects, enzyme activities and levels of gene expression were assessed, battery of biomarker utilized by the integrated biomarker response (IBRv2) model. The 96 h-LC50 of spirodiclofen, spiromesifen and spirotetramat were 0.14, 0.12 and 5.94 mg/L, respectively. Yolk sac deformity, pericardial edema, spinal curvature and tail malformation were observed. Three spirocyclic acids were unfavouring the lipid accumulation of by inhibited the acetyl-CoA carboxylase (ACC), fatty acid synthesis (FAS), fatty acid binding proteins (FABP2) and lipoprotein lipase (LPL) activity. The total cholesterol (TCHO) level significantly decreased in the 0.072 mg/L spirodiclofen group and 0.015 and 0.030 mg/L in the spiromesifen groups. No expected change in spirotetramat group on the TCHO and triglycerides (TGs) levels for any of the treatments. The mRNA levels of the genes related to lipid metabolism also significantly altered. In both spirodiclofen and spiromesifen, ACC achieved the highest scores among a battery of biomarkers using integrated biomarker response (IBRv2). The results suggest that spiromesifen was the most toxic for embryos development and spirodiclofen was the most toxic for lipid metabolism in embryos. The 0.07 mg/L of spirodiclofen, 0.05 mg/L of spiromesifen and 2.00 mg/L would cause malformation on zebrafish embryos. This study will provide new insight that fatty acid metabolism may be a suitable biomarker for the spirocyclic tetramic acids in fish species.

Marrow fat accumulates in diabetic conditions but remains elusive. The published works on the relationships between marrow fat phenotypes and glucose homeostasis are controversial.To detect the association of insulin resistance with marrow adiposity in postmenopausal women with newly diagnosed type 2 diabetes (T2D) using chemical shift-encoded water-fat MRI.We measured vertebral proton density fat fraction (PDFF) by 3T-MRI in 75 newly diagnosed T2D and 20 nondiabetic postmenopausal women. Bone mineral density (BMD), whole body fat mass and lean mass were determined by dual-energy X-ray absorptiometry. Insulin sensitivity was estimated using the homeostasis model assessment of insulin resistance (HOMA-IR).Lumbar spine PDFF was higher in women with T2D (65.9 ± 6.8%) than those without diabetes (59.5 ± 6.1%, P = 0.009). There was a consistent inverse association between the vertebral PDFF and BMD. PDFF had a positive association with glycated hemoglobin and HOMA-IR but not with fasting plasma glucose and insulin. PDFF was significantly increased, and BMD was decreased in a linear trend from the lowest (1.90) to highest (≥2.77) HOMA-IR quartile. Multivariate linear regression analyses revealed a positive association between log-transformed HOMA-IR and PDFF after adjustment for multiple covariates (ß = 0.382, P 0.001). The positive association of HOMA-IR with PDFF remained robust when total body lean mass and fat mass, BMD was entered into the multivariate regression model, respectively (ß = 0.293 and ß = 0.251, respectively; all P0.05).Elevated HOMA-IR was linked to higher marrow fat fraction in postmenopausal women with newly diagnosed T2D independently of body compositions.

Curcumin (CM) has multiple pharmacological activities including anti-fungal activity, but its clinical application is limited due to low solubility in aqueous media, poor bioavailability and extensive first pass metabolism. We aimed to resolve the limitation and enhance antifungal activity of CM using nanotechnology. Using silk fibroin (SF) as a carrier, we fabricated curcumin-silk fibroin nanoparticles (CM-SF NPs) by solution enhanced dispersion of supercritical CO₂ (SEDS) technique. The characterization of CM-SF NPs was analyzed using scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC) and thermo gravimetric apparatus (TGA). Following characterization of the NPs, we evaluated the antifungal activity of CM-SF NPs against Candida albicans in vitro and in vivo. A SF-based drug delivery system (CM-SF NPs, 85 ± 15 nm) was established by SEDS. Compared to original CM, water solubility of CM-SF NPs was improved, and its antifungal activity was enhanced. The natural compound-loaded SF nanoparticles may be a promising therapeutic candidate for fungal infection.

A highly enantioselective (49–99% ee) Michael addition/lactonization cascade process has been developed to construct 3,4-dihydropyran-2-one in the presence of a bifunctional squaramide. Various α,β-unsaturated N-acyl heterocycles were well tolerated and afforded 3,4-dihydropyran-2-ones in moderate to excellent isolated yields (50–99%). Both cyclic and acyclic β-diketones functioned as appropriate donors. The resulting 3,4-dihydropyran-2-ones could be readily converted into oxadecalinones.

A highly enantioselective (84–97% ee) cascade Michael/acyl transfer reaction of α-nitroketones to a wide range of 2-hydroxychalcones was established in the presence of a bifunctional squaramide. Although aliphatic α-nitroketones were revealed to be a class of challenging substrates with unsatisfactory reactivity or enantioselectivity by previous reports, good isolated yields and excellent enantiopurities have been achieved via our catalytic protocol. γ-Nitroketones created by this new methodology were versatile building blocks possessing profound further synthetic utility.

Various non-noble metal-based electrocatalysts have been studied to replace platinum for hydrogen production. The formation of a composite through adding a conductive polymer could be an efficient way to further enhance the performance of those catalysts further but applying conductive polymers in electrochemical catalysis has been hardly ever reported. In this research, we synthesized an extraordinary WO3@NPRGO composite using phosphotungstic acid-polypyrrole/reduced graphene oxide (PW12-PPy/RGO) as a precursor. The oxidation polymerization of pyrrole (Py) monomers prevents the PW12 and RGO from aggregating and WO3 nanoparticles were homogeneously imbedded in the N, P-codoped RGO nanosheets, which not only exposed massive active sites, but also resulted in faster charge transfer. Electrochemical characterizations reveal that the composite exhibits greatly enhanced electrocatalytic activity and has impressive long-term stability for the hydrogen evolution reaction. Our works opens a new path for the design and synthesis of novel nanostructure electrocatalysts.

Dental caries, starting from demineralization of enamel and dentine, is closely related with acid-producing bacteria in oral cavity, for example, Streptococcus mutans. Remineralization is an efficient way to prevent the disease progression and facilitate the therapy of incipient caries. Therefore, for the purpose of effective dentine repair, remineralization and antibacterial should be combined simultaneously. However, most of the literatures only focus on one single aspect, while combing remineralization and antibacteria for dentine repair in one system is rarely reported. Here in this work, phosphoryl-terminated poly(amide-amine) dendrimers were loaded with apigenin, a water-nonsoluble drug antibacterial agains Streptococcus mutans. The apigenin-loaded dendrimers bind strongly with dentine, which further induce dentine tubules occlusion through mineralization in artificial saliva, and the release of apigenin can prevent further erosion of dentine by bacteria. Meanwhile, the phosphorylated dendrimers are easily prepared by one-step modification of poly(amide-amine) and exhibit good cytocompatibility. This strategy developed here can provide reference for the design of effective anti-caries materials.

Hypothesis Shear-thickening micelles were mostly made of cationic surfactants, but shear-thickening was rarely reported in the zwitterionic/anionic surfactants. Since wormlike micelles were essential in shear-thickening systems, it should be common for the hybrid wormlike micelles formed by zwitterionic/anionic surfactants, and their fundamental features need to be clarified. Experiments The micellization of zwitterionic surfactant homologies alkyl dimethyl amidopropyl hydroxyl sulfobetaine (AHSB) and sodium dodecyl sulfate (SDS) in brine was studied, and various environmental factors were considered systematically. Light scattering, rheology, zeta potential, 1H NMR and cryo-TEM techniques were employed to characterize the AHSB/SDS wormlike micelles. Findings AHSB/SDS hybrid wormlike micelles were formed in a wide xSDS region to endow them with apparent viscosities, in which the electrostatic and hydrophobic interactions between AHSB and SDS molecules were critical. AHSB with the longer tail, the higher cAHSB and cNaCl were advantageous to enhance the viscosity because of the longitudinal growth of wormlike micelles. The shear-thickening AHSB/SDS samples were commonly composed of unbranched wormlike micelles with various length, and the shear-induced alignment of wormlike micelles was the major cause as verified by cryo-TEM. Moreover, the quantitative relationships on the critical shear rate ɣc were established, and the activation energies were obtained from the temperature-dependent ɣc.

A sulfa-Michael/aldol/lactonization cascade reaction has been established to construct isotetronic acid-fused thiochromanes in a highly stereoselective fashion (≥11:1 dr, 35-98% ee). The tricyclic products were obtained in 35-99% isolated yields in the presence of a bifunctional squaramide. Three reactive sites of β,γ-unsaturated α-ketoester, including the less-explored ester carbonyl group, were sequentially utilized to construct two fused heterocycles in a one-pot operation.

Soft-oxometalates (SOMs) are colloid suspensions of superstructured assemblies of polyoxometalates (POMs) and are found to be very effective photo-catalysts in a number of chemical reactions. The stabilization of SOMs generally requires legends or stabilizers, e.g., polymers and surfactants. In this paper, a light responsive azobenzene surfactant, C10AZOC2N3, was developed and used to stable {Mo132} SOMs. Various techniques such as Dynamic light scattering, TEM, UV-Vis spectra and cyclic voltammetry were employed to characterize the experimental results. The outstanding structure-directing effect of surfactant self-assembly micelles in solution on inorganic counter-anions was demonstrated. Different amount of cyclohexane was solubilized into C10AZOC2N3 micelles to successfully control the size of {Mo132} SOMs cluster. Furthermore, the clusters exposed to UV light for a certain time can be served as a second trigger to control the size of SOMs due to the trans-cis conformation transition of surfactant molecules. The redox potentials of C10AZOC2N3-{Mo132} SOMs were investigated as the cluster size varied. Interestingly, the redox potential of {Mo132} was not affected by the cluster size, indicating that the presence of surfactant did not change the main function of {Mo132} as an electrochemical catalyst, but merely assisted in the size control of SOM aggregation.

Hydrogels that possess adequate toughness in bulk and at soft interface are highly desirable. We report a fully physically crosslinked dual Amylopectin (Amy, the first network)/poly(N-hydroxyethyl acrylamide) (PHEAA, the second network) hydrogel, where both networks were hydrogen bonding (H-bonding) crosslinked, with super toughness in bulk and tunable adhesion at hydrogel-soft tissue interface. Through adjustment of hydrogen bond density, strong and tough hydrogels were prepared that exhibited different levels of adhesion strength and three adhesive failure mechanisms. We replaced Amy with oxidized starch (OSA) to synthesize dual and hybrid chemically/physically crosslinked OSA/PHEAA double network (DN) hydrogels that were capable of forming Schiff's bases at hydrogel-hydrogel or hydrogel-tissue interfaces, aside from interfacial H-bonding, incurring sustained, high interfacial toughness (1850 J m−2 hydrogel-hydrogel and 610 J m−2 hydrogel-tissue) in wet environments. Such tough and adhesive DN hydrogels have great potential in various applications such as engineering of artificial soft tissues or implantable devices that are intended to adhere to internal organs or tissues.

Hypothesis/Introduction. Berberine, a natural compound, has multiple pharmacological activities to promote islet function. We hypothesized that berberine could reshape the local renin-angiotensin system (RAS) balance to ameliorate the development of obesity via the modulation of autophagy. Materials and methods. After 8 weeks of administration of intragastric berberine to ob/ob mice, metabolic parameters, islet structure, and the angiotensin-converting enzyme 2 (ACE2) expression were detected. Additionally, ACE2 knockout (ACE2KO) mice were fed a low-fat diet for 16 weeks. Furthermore, we measured changes in the islet ultrastructure by transmission electron microscope (TEM) and protein expression of LC3 and SQSTM1/p62 by immunohistochemistry in ob/ob and ACE2KO mice. Results. Prolonged exposure to palmitate increased the expression of ACE and AngII type 1 receptor (ATR1) and decreased the ACE2 expression, which was partly offset by berberine. In ob/ob mice, berberine increased in tolerance to glucose, improved abnormal β-cell and α-cell distributions, upregulated ACE2 expression, and decreased autophagosomes and the expression of LC3 and SQSTM1/p62. Autophagosomes and expression of LC3 and SQSTM1/p62 were increased in ACE2KO mice. Conclusions. We demonstrated that berberine may improve the pancreatic islet function by regulating local RAS-mediated autophagy under metabolic stress.

Rewritable information record materials usually demand not only reversibly stimuli-responsive ability, but also strong mechanical properties. To achieve one photochromic hydrogel with super-strong mechanical strength, hydrophobic molecule spiropyran (SP) has been introduced into a copolymer based on ion-hybrid crosslink. The hydrogels exhibit both photoinduced reversible color changes and excellent mechanical properties, i.e., the tensile stress of 3.22 MPa, work of tension of 12.8 MJ m-3 , and modulus of elasticity of 8.6 MPa. Moreover, the SP-based Ca2+ crosslinked hydrogels can be enhanced further when exposed to UV-light via ionic interaction coordination between Ca2+ , merocyanine (MC) with polar copolymer chain. In particular, hydrogels have excellent reversible conversion behavior, which can be used to realize repeatable writing of optical information. Thus, the novel design is demonstrated to support future applications in writing repeatable optical information, optical displays, information storage, artificial intelligence systems, and flexible wearable devices.

Despite the widespread clinical application of chemotherapeutic anticancer drugs, their adverse side effects and inefficient performances remain ongoing issues. A drug delivery system (DDS) designed for a specific cancer may therefore overcome the drawbacks of single chemotherapeutic drugs and provide precise and synergistical cancer treatment by introducing exclusive stimulus responsiveness and combined chemotherapy properties. Herein, we report the design and synthesis of a supramolecular drug delivery assembly 1 constructed by orthogonal self-assembly technique in aqueous media specifically for application in liver cancer therapy. Complex 1 incorporates the β-cyclodextrin host molecule-functionalized organoplatinum(II) metallacycle 2 with two specific stimulus-responsive motifs to the signaling molecule nitric oxide (NO), in addition to the three-armed polyethylene glycol (PEG) functionalized ferrocene 3 with redox responsiveness. With this molecular design, the particularly low critical aggregation concentration (CAC) of assembly 1 allowed encapsulation of the commercial anticancer drug doxorubicin (DOX). Controlled drug release was also achieved by morphological transfer via a sensitive response to the endogenous redox and NO stimuli, which are specifically related to the microenvironment of liver tumor cells. Upon combination of these properties with the anticancer ability from the platinum acceptor, in vitro studies demonstrated that DOX-loaded 1 is able to codeliver anticancer drugs and exhibit therapeutic effectiveness to liver tumor sites via a synergistic effect, thereby revealing a potential DDS platform for precise liver cancer therapeutics.

Avian Tembusu virus (TMUV) is a newly emerging avian pathogenic flavivirus that spreads rapidly, has an expanding host range and undergoes cross-species transmission. Our previous study identified avian monocytes/macrophages as the key targets of TMUV infection, since the infection of host monocytes/macrophages was crucial for the replication, transmission, and pathogenesis of TMUV. The polarization of host macrophages determines the functional phenotypes of macrophages; however, the effect of TMUV infection on macrophage polarization remains unclear. Here, we analysed the expression spectra of the marker genes of macrophage polarization upon TMUV infection in the HD11 chicken macrophage cell line and primary monocytes/macrophages isolated from the peripheral blood of specific pathogen-free (SPF) chickens and ducks. We found that viral replication mainly induced M1 marker genes and triggered nitric oxide (NO) release at different levels, suggesting that TMUV infection led mainly to host macrophages polarizing into the classically activated (M1) type. The NO that was increased upon infection did not function as an antiviral agent against TMUV, since the replication of TMUV in HD11 cells was not affected by the addition of an organic NO donor. Furthermore, upon TMUV infection, polarized HD11 cells exhibited increased migration but reduced phagocytosis, as evidenced by scratch assay and neutral red uptake assay, respectively. Our present study characterized the polarization of host monocytes/macrophages upon TMUV infection, which may lay a foundation for further research on the immune escape mechanism and pathogenic mechanism of TMUV.

A stereoselective annulation protocol was developed to construct dihydrofuranoindoles from readily available starting materials. In the presence of a bifunctional squaramide, the Friedel-Crafts alkylation/annulation cascade process occurred smoothly to provide dihydrofuranoindoles in 26-95% isolated yields exclusively as

A versatile ionic crosslink lithography (ICL) approach is reported to achieve geometry transitions of strong polyvinyl alcohol/sodium alginate (PVA/SA) hydrogels in a controllable and programmable manner. Specifically, localized PVA/SA and PVA/SA/Fe3+ hydrogel domains of significantly different swellabilities (i.e., in-plane gradient) are created by patterning and selective ionic crosslinking of one single type of PVA/SA hydrogel. A simple two-step sequential pre- and free-swelling, or each alone, directs the patterned, inhomogeneous hydrogel to transform in various programmable and quasi-quantitative ways through local bulging and/or global buckling. All types of shape changing are reversible and repeatable due to the reversible nature of ionic coordination in the hydrogel networks. The flexibility and versatility of 3D printing is also demonstrated in creating through-thickness gradient in PVA and PVA/SA hydrogel assemblies with similar morphing capability. The ICL approach developed in this work may help shed some light on developing strong and shape morphing hydrogels as soft sensors and actuators and for potentially biomimetic transformations. The ICL approach may also be transferable to fabrication of many other types of hydrogel materials for similar applications.

An enantioselective (92-99% ee) Michael/aldol cascade reaction between 4,4,4-trifluoroacetoacetates and α,β-unsaturated enones was established in the presence of cinchona alkaloid-based primary amines. Various β-CF3-cyclohexanones were constructed in high yields (81-99%) as a couple of separable diastereomers. This tandem reaction was sensitive to acidic co-catalysts, with a Michael/aldol condensation process favorably occurring to generate β-CF3-cyclohexenones (42-69% yield, 84-96% ee) in the presence of trifluoroacetic acid.

To investigate the biological pathways involved in phthalate-induced developmental effects, zebrafish embryos were exposed to different concentrations of di-(2-ethylhexyl) (DEHP) and di-butyl phthalate (DBP) for 96 h. Embryonic exposure to DEHP and DBP induced body length decrease, yolk sac abnormities, and immune responses (up-regulation of immune proteins and genes). The lipidomic results showed that at a concentration of 50 μg/L, DEHP and DBP significantly reduced the levels of fatty acids, triglycerides, diacylglycerol, and cholesterol. These effects are partly explained by biological pathway enrichment based on data from the transcriptional and proteomic profiles. Co-exposure to DBP and ER antagonist did not significantly relieve the toxic symptoms compared with exposure to DBP alone. This indicates that phthalate-induced developmental abnormities in zebrafish might not be mediated by the ER pathway. In conclusion, we identified the possible biological pathways that mediate phthalate-induced developmental effects and found that these effects may not be driven by estrogenic activation.

As promising structural materials, various tough hydrogels have been developed recently by incorporating various kinds of bonds. An important challenge is to use dual physical cross-linking to develop both toughness and self-recovery in a single material. Here we report smart, strain-responsive hydrogels composed of a fully physically linked agarose/poly(acrylic acid)-ferric ion (agar/PAAc-Fe3+) double network (DN) with high toughness and pH-sensitivity. These hydrogels were fabricated in a one-pot reaction to generate dual physical cross-linking through, first, a hydrogen-bonded cross-linked agarose network, and, second, a physically linked PAAc-Fe3+ network via Fe3+ coordination interactions. The DN hydrogels possessed high toughness, with breaking strain of 1130%, fast self-recovery properties in ambient conditions (100% recovery in 30 min) and self-healing properties (the healed hydrogels can be manually stretched up to 700% of their original length after self-healing for 60 h from the cut-off state). In addition, the hydrogels exhibited pH-sensitivity due to the dissociation of ionic coordinate bonds between –COO− ions of the PAAc chains and Fe3+ ions. Double-layer hydrogel strips with two different concentrations of PAAc formed a “C”-shaped material when initially immersed in pH 7 solution and then soaked in a pH 3 solution. These characteristics make the hydrogels attractive candidates for tissue engineering, soft actuators and flexible electronics.

Background Angelica root is the dry root of the Umbelliferae plant Angelica sinensis (oliv) Diels. Angelica organic acid (OA) is the main active ingredient in Angelica sinensis, and it exerts potential anti-atherosclerotic effects by preventing Oxidized low-density lipoprotein (Ox-LDL) induced endothelial injury. To study the protective effects of OA on ox-LDL-induced HUVECs autophagic flux dysfunction and inflammatory injury. Methods OA were isolated by water extraction and alcohol precipitation, and then the content of ferulic acid (FA) in the OA was determined by high performance liquid chromatography. The ox-LDL-induced endothelial injury model was established. The effect of ferulic acid on the survival of Human umbilical vein endothelial cells (HVUECs) was detected by CCK-8 assay. HUVECs were pretreated with different concentrations of OA (20 μmol/L, 40 μmol/L, and 80 μmol/L), and Western Blot was used to detect the expressions of LC3II, p62, MCP-1, VCAM-1 and LOX-1. The autophagosomes in HUVECs were observed by transmission electron microscopy (TEM). Results 20 μmol/L OA could increase the expression of LC3II and decrease the expression of p62, MCP-1, VCAM-1 and LOX-1. The results of TEM showed that angelica organic acids promoted cell organelle degradation in autolysosomes. Conclusion OA could reduce inflammation, protect endothelial cells and play an anti-atherosclerotic role by enhancing the autophagy flux of damaged endothelial cells, in which FA the major active ingredient of OA played a major role.

A novel organocatalytic cascade process initiated by 1,6-conjugated addition has been successfully developed. A range of pharmaceutically active 2-amino-4-aryl-4H-chromenes were readily obtained in high yields (88%-99%) and excellent enantiopurities (86%-99% ee). The functionalized para-Quinone methides (p-OMs) could be facilely obtained.