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Polyvinyl alcohol (PVA)/laponite (LP) nanocomposite coatings were fabricated via a facile one-step coassembly process. The formed nanocoatings contain a high concentration of LP nanosheets, which can be well aligned along the substrate surface during the coassembly process. Due to the highly orientated structure, the flexible nanocoatings exhibit ultra-high transparency and superior mechanical properties, and can also act as excellent gas barriers. Such nanocoatings can be exceptional candidates for a variety of applications, such as food packaging.

An enantioselective [4+1] spiroannulation of α-bromo-β-naphthols with azoalkenes has been developed for the one-step construction of a new class of pyrazoline-based spirocyclic molecules. Using chi...

The p-i-n junction structure has garnered great interest from researchers due to its increased photoactive area and wider space charger region compared with that of the p-n junction. Herein the ult...

Metal–organic frameworks (MOFs) with plenty of active sites and high porosity have been considered as an excellent platform for the electroreduction of CO2, yet they are still restricted by the low...

The silver nanowire (AgNWs) / cotton fiber was used as a conductive substrate with high conductivity charge transfer. Then the polyaniline (PANI) molecular chain was fixed on the AgNWs / cotton fiber by in-situ polymerization to prevent its dedoping and improve its cyclic properties. Thus the flexible capacitor electrode material with conductive, specific capacity and cyclic properties was obtained. The results showed that when the mass ratio of KH-560 to AgNWs/cotton fiber was 3:1, the grafting rate of epoxide group on the modified AgNWs/cotton fiber was the highest. When the mass ratio of aniline to modified AgNWs cotton fabric was 3:1, the PANI content of in-situ polymerization on the fabric surface was the highest, 20.83%. The specific capacity of PANI/AgNWs/cotton fiber electrode material was the highest, 154 F/g, after 5000 cycles of charging and discharging, the specific capacity could keep 96%. It is worth mentioning, the introduction of PANI and AgNWs could significantly improve the wear resistance of cotton fiber, the friction resistance of the cotton fabric increased to 36,000 times. It is provided a new idea for design a flexible capacitor electrode material integrating electrical conductivity and cyclic stability.

Background Red flower oil is a group of herbal medicinal liniments widely used in China and Southeast Asia. The color of red flower oil is adjusted to red or brownish-red by adding natural dyes. Objective The objective of this study is to identify and quantify the synthetic dyes illegally used in red flower oil. Methods Thirty-two batches of red flower oil (from nine manufacturers) were collected from different cities in China. High-performance liquid chromatography-diode array detection-mass spectrometry (HPLC–DAD–MS) analysis was performed to identify the chemical dyes in the samples, and high-performance liquid chromatography-diode array detection (HPLC–DAD) was used to quantify the chemical dyes. Results Sudan I, Sudan IV, and Solvent Red 207 were detected in nine batches of preparations (from three manufacturers) with concentration ranges of 101.7–214.9 μg/mL for Sudan I, 24.0–41.0 μg/mL for Sudan IV, and 147.5–221.7 μg/mL for Solvent Red 207. Conclusion In present study, sudan I, sudan IV, and solvent red 207 were detected in red flower oil. The control of chemical dyes in food and drug should be further studied and not limited to sudan dyes. Highlights It is the first report about the detection of solvent red 207 in food and drug. The illegal use of those chemical dyes should be regarded as serious violation of good manufacturing practice (GMP) and might be dangerous for the patients.

Carbon nanodots (CDs) based fluorescent nanoprobes have recently drawn much attention in chemo-/bio-sensing and bioimaging. However, it is still challenging to integrate the colorimetric and fluorometric dual readouts into a single CD. Herein, novel hybrid CDs (HCDs) are prepared by a simple microwave-assisted reaction of citric acid (CA), branched polyethyleneimine (BPEI) and potassium thiocyanate (KSCN). As-prepared HCDs show extraordinary properties, including excitation-dependent emission, satisfactory fluorescence quantum yield (46.8%), excellent biocompatibility and optical stability. Significantly, the fluorescence intensity at 450 nm exhibits linear correlation over the Fe3+ concentration from 1 μmol/L to 150 μmol/L with a detection limit (LOD) of 52 nmol/L. Meanwhile, the solution color changes from colorless to orange, and the absorbance at 460 nm increased linearly with Fe3+ concentration ranging from 0.02 mmol/L to 5 mmol/L (LOD: 3.4 μmol/L). All the evidence illustrates that the HCDs can be conditioned for specific Fe3+ sensing with colorimetric and fluorometric dual readouts, which has also been verified with paper-based microchips. The possible mechanism is attributed to the specific interactions between surface functional groups on the HCDs and Fe3+. Additionally, the HCDs are successfully applied in sensing Fe3+ in wastewater and living cells, demonstrating its potential applications in future environment monitoring and disease diagnosis.

Rhodosporidium toruloides is an oleaginous yeast capable of producing a variety of biofuels and bioproducts from diverse carbon sources. Despite numerous studies showing its promise as a platform microorganism, little is known about its metabolism and physiology. In this work, we investigated the central carbon metabolism in R. toruloides IFO0880 using transcriptomics and metabolomics during growth on glucose, xylose, acetate, or soybean oil. These substrates were chosen because they can be derived from plants. Significant changes in gene expression and metabolite concentrations were observed during growth on these four substrates. We mapped these changes onto the governing metabolic pathways to better understand how R. toruloides reprograms its metabolism to enable growth on these substrates. One notable finding concerns xylose metabolism, where poor expression of xylulokinase induces a bypass leading to arabitol production. Collectively, these results further our understanding of central carbon metabolism in R. toruloides during growth on different substrates. They may also help guide the metabolic engineering and development of better models of metabolism for R. toruloides.Key points• Gene expression and metabolite concentrations were significantly changed.• Reduced expression of xylulokinase induces a bypass leading to arabitol production.• R. toruloides reprograms its metabolism to allow growth on different substrates.

Surface modification is a main approach for natural polymers to gain flame retardancy. Developing a green coating system to endow natural polymers with flame retardancy and wash-durability is extremely challenging. Herein, a sandwich-like structured nanocoating system with mutual restricted network through electrostatic interaction, hydrogen bonding, and chemical bonding were designed via multi-layered coating and UV curing. The coated natural cotton fabrics demonstrated exellent flame retardancy, wash durability, and hydrophobicity. The chemicals involved include montmorillonite (MMT), ammonium polyphosphate (APP), acrylated polyurethane (PU), branched polyethylenimine (bPEI), and polydimethylsiloxane (PDMS). The concentration of bPEI governed the wash durability of the coated fabrics, and those samples with a higher concentration of bPEI possessed better wash durability. Meanwhile, bPEI served as a flammable resource to deteriorate the flame retardant performance. The systematic evaluations of the coated fabrics after washing demonstrated that this coating system can maintain balanced wash durability and flame retardancy.

Despite the widespread use of silica nanoparticles (SiNPs), their metabolic impact and mechanisms of action have not been well studied. Exposure to SiNPs induces insulin resistance (IR) in hepatocytes by endoplasmic reticulum (ER) stress via inositol-requiring protein 1α (IRE1α) activation of c-Jun N-terminal kinases (JNK). It has been well established that stearoyl CoA desaturase (SCD1) and its major product oleic acid elicited beneficial effects in restoring ER homeostasis. However, the potential coordination of SCD1 and IRE1α in determining SiNP regulation of insulin signaling is unclear. Herein, we investigated the effects of SCD1 and oleic acid on IR induced by SiNPs or thapsigargin in hepatocytes. SCD1 overexpression or oleic acid efficiently reversed SiNP-induced ER stress and IR, whereas the effects of thapsigargin treatment could not be restored. Thapsigargin diminished SCD1 protein levels, leading to the accumulation of IRE1α and sustained activation of the IRE1α/JNK pathway. Moreover, knockdown of activating transcription factor 4 (ATF4) upstream of SCD1 suppressed SiNP-induced SCD1 expression, rescued the activated IRE1α, and inhibited insulin signaling but was not able to restore the effects of thapsigargin. Collectively, downregulation of SCD1 and excess accumulation of IRE1α protein prevented the beneficial effects of exogenous oleic acid on IR induced by ER stress. Our results provide valuable mechanistic insights into the synergic regulation of IR by SiNPs and ER stress and suggest a combinational strategy to restore ER homeostasis by targeting SCD1 and IRE1α proteins, as well as supplementation of unsaturated fatty acids.

Purpose To present a clinical case of lamellar macular hole with lamellar hole-associated epiretinal proliferation in a pediatric familial exudative vitreoretinopathy patient. Retinal findings are described, and spectral domain optical coherence tomography documentation is provided. The efficacy of surgical intervention is also discussed. Methods A 4-year-old girl presented with poor vision in her right eye, which was discovered during routine physical examination. Clinical examination revealed familial exudative vitreoretinopathy in both eyes and a lamellar macular hole in the right eye. Both of the patient's parents were also examined, which revealed familial exudative vitreoretinopathy in the girl's father. The patient underwent vitrectomy, inner limiting membrane and lamellar hole-associated epiretinal proliferation peeling, and air-fluid exchange. Results Images obtained with optical coherence tomography revealed lamellar hole-associated epiretinal proliferation at the lamellar defect edge in the patient's right eye. Postoperative examination showed that the lamellar macular hole had closed. Conclusion Pediatric familial exudative vitreoretinopathy patients may develop lamellar macular hole with lamellar hole-associated epiretinal proliferation. Vitreoretinal surgery effectively closes this type of macular hole.

The compression behaviour of fine-grained soils is mainly controlled by pore collapse, while the compression behaviour of sands is mainly governed by grain breakage. For soils containing both fine and coarse soil particles such as quartz and calcite grains, the compressibility may depend on both pore collapse and grain breakage. In this study, the compressibility of two natural soils reported in the literature was first analysed in this sense, showing the effect of grain breakage on the compressibility of soils. To further verify this phenomenon, high-pressure oedometer tests were carried out on a natural stiff clay containing a significant fraction of granular elements. The obtained results confirmed the significant effect of grain breakage. In order to better understand the role of fines in the grain breakage phenomenon, artificial sand–clay mixtures were prepared with different fine fractions and tested in oedometer. Results show that the compression behaviour of sand–clay mixtures can be roughly divided into three zones according to the fine fractions: at low fine fractions, the compression behaviour is governed by grain breakage; at high fine fractions, the compression behaviour is governed by the pore collapse of fines; and at medium fine fractions, both pore collapse and grain breakage affect the compression behaviour. In this last case, pore collapse occurs first, letting grains to be well in contact either directly (grain–grain contacts) or indirectly (grain–fine grain contacts) to activate the grain breakage phenomenon upon further loading. This is consistent with the identified compression behaviour of natural fine-grained soils.

The “coordination-insertion” ring-opening polymerization (ROP) mechanism has so far been the monopoly of metal catalysts. In this work, we present a metal-free “coordination-insertion” ROP of trimethylene carbonate (TMC) and ε-caprolactone (ε-CL), as well as their sequential block copolymerization, with N-trimethylsilyl-bis (trifluoromethanesulfonyl)imide (TMSNTf2) as the non-metallic initiator/catalyst. TMSNTf2 was proposed to work through an unprecedented metal-free “coordination-insertion” mechanism, which involves the coordination of monomer to the Si atom of TMSNTf2, the nucleophilic attack of the –NTf2 group on the coordinated monomer, and the cleavage of the acyl–oxygen bond of the monomer. The proposed metal-free “coordination-insertion” ROP was studied by NMR, SEC, and MALDI-TOF analyses. In addition, the TMSNTf2-mediated ROP of TMC and ε-CL led to linear and cyclic polymers following two-stage first-order polymerization processes, as evidenced by structural analyses and kinetics study, which further demonstrated the metal-free “coordination-insertion” mechanism., The first metal-free “coordination-insertion” ROP of cyclic carbonate and lactones mediated by N-trimethylsilyl-bis(trifluoromethanesulfonyl)imide (TMSNTf2) was proposed, which in the past was exclusively the monopoly of metal complex catalysts.

Ure2 regulates nitrogen catabolite repression in Saccharomyces cerevisiae. Deletion of URE2 induces a physiological state mimicking the nitrogen starvation and autophagic responses. Previous work has shown that deletion of URE2 increases the fermentation rate of some wine-producing strains of S. cerevisiae. In this work, we investigated the effect of URE2 deletion (ΔURE2) on the metabolism of S. cerevisiae. During growth on glucose, the ΔURE2 mutant grew at a 40% slower rate than the wild type; however, it produced ethanol at a 31% higher rate. To better under the behavior of this mutant, we performed transcriptomics and metabolomics. Analysis of the RNA sequencing results and metabolite levels indicates that the mutant strain exhibited characteristics of both nitrogen starvation and autophagy, including the upregulation of allantoin, urea, and amino acid uptake and utilization pathways and selective autophagic machinery. In addition, pyruvate decarboxylase and alcohol dehydrogenase isoforms were expressed at higher rates than the wild type. The mutant also accumulated less trehalose and glycogen, and produced more lipids. The induction of a nitrogen starvation-like state and increase in lipid production in nitrogen-rich conditions suggest that URE2 may be a promising target for metabolic engineering in S. cerevisiae and other yeasts for the production of lipids and lipid-derived compounds. • Deletion of URE2 increases ethanol and lipid production in Saccharomyces cerevisiae. • Deletion of URE2 reduces glycogen and trehalose production. • Metabolic changes mimic nitrogen starvation and autophagic response.

Lipid-polymer hybrid nanoparticles (LPNs) are promising drug delivery systems in various of disease treatment areas, particularly for cancer treatments. Here, a water-insoluble antitumor agent, hydroxycamptothecin (HCPT), was successfully incorporated into LPNs formed from polylactic-co-glycolic acid (PLGA), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-(methoxy(polyethylene glycol)-2000) (DSPE-PEG2000), and lecithin, by a modified single emulsification-solvent evaporation method. Quality-by-design (QbD) strategy composed of Plackett–Burman and Box–Behnken designs were applied for optimizing HCPT-LPNs with desired properties. The optimized HCPT-loaded lipid-polymer hybrid nanoparticles (HCPT-LPNs) were on the nanoscale, with a final size of 220.9 nm, drug loading of 2.50%. HCPT-LPNs were highly stable in plasma and had pH- and drug loading-related sustained release characteristics. The in vitro cytotoxicity of HCPT-LPNs against MCF-7 and HepG2 cells showed that HCPT-LPNs had higher in vitro cytotoxicity than HCPT solution (HCPT-Sol) with reduced cell viability and IC50 values. In vivo pharmacokinetic assays demonstrated that the AUC of HCPT-LPNs was more than 3 times higher than that of HCPT-Sol after tail vein injection in SD rats. Tumor growth was significantly inhibited compared with HCPT-Sol after a single tail vein injection of HCPT-LPNs in murine LLC-GFP-luc lung cancer bearing mice at a dose of 6 mg/kg, without severe side effects. These results indicate that HCPT-LPNs are the promising drug delivery system for antitumor treatments.

The isolable anionic oxoborane 3 and thioxoborane 4 have been assembled using a 1,2-bis(imino)acenaphthene ligand (Dip-BIAN). Structural characterization and DFT calculations confirmed that two compounds contain terminal doubly bonded B[double bond, length as m-dash]E (E = O, S) groups, respectively, in which only the B[double bond, length as m-dash]O group is associated with imidazolium via a hydrogen bond.

Porphyrin-based photocatalytic oxygen evolution (POE) has exhibited great potential in artificial photosynthesis; however, a few reports exist on efficient nanocatalytic systems due to the fast photoinduced charge recombination. Here, cobalt(III) tetraphenylporphyrin (CoP) nanowires (NWs) are first synthesized at a large-scale via a simple chemical reaction, and transformed in situ into zero-dimensional CoP/NGQDs nanocomposites by adding nitrogen-doped graphene quantum dots (NGQDs) as the template and dopant. Under the visible light irradiation, no detectable POE activity of CoP NWs is observed in an acid heterogeneous system, while the currently highest POE rate on the molecule (350 μmol g−1 h−1) is achieved with CoP/NGQDs as the photocatalyst. Systematic experiments reveal that the NGQDs-limiting self-assembly of CoP molecules along the axial direction and subsequent formation of Z-scheme CoP/NGQDs heterojunctions are crucial for efficient POE. The nanostructures lead to enough exposure of the central Co atom as POE active sites and longer recombination lifetime of the photoinduced charge in CoP/NGQDs (87.8 ps) than that in CoP NWs (32.2 ps) due to the generation of (CoP+·NGQDs−)* exciplex. This work provides a new strategy to use a nature-like semiconductor molecule as a direct catalyst for artificial photosynthesis.

Dendrobium catenatum, which grows on the semi humid rocks in the mountains, has been at the top of the ‘Nine Immortals of China’ since ancient times. It is a kind of yin tonic medicine and its main active component is polysaccharide. Cellulose synthase-like D(CslD) genes were predicted to catalyse the biosynthesis of 1,4-β-d-glycan backbone of hemicelluloses, which plays fundamental roles in plant development. To investigate the role of CslD in the development of D. catenatum, eight CslD genes (DcCslD1,2a,2b,3a,3b,4a,4b,5) were identified. The results of protein prediction and analysis showed that CslD2a/2b/4a/4b proteins were acidic proteins. All the proteins had obvious hydrophobic or hydrophilic regions, and had transmembrane structure. Phylogenetic analysis revealed that the DcCslD family could be divided into group I, II, III and IV. DcCslD proteins had a typical Cellulose synthase domain and similar protein structures to the CslDs of other plants. Their promoter regions contain cis regulatory elements related to stress and hormone response. The results of qRT-PCR showed that the identified DcCslDs were differentially expressed in roots, stems and leaves. Most of them were highly expressed in stems and leaves. The environmental stresses examination showed that the expression levels of DcCslD5 were closely associated with drought-recovery treatment; the expression levels of DcCslD1, DcCslD2a, DcCslD2b, DcCslD3a and DcCslD5 were significantly influenced by low temperature. This study systematically analyzed the sequence characteristics of CslD protein of D. catenatum, which can provide reference for further study on the function of CslD protein in the polysaccharide metabolism of D. catenatum. Supplemental data for this article is available online at https://doi.org/10.1080/13102818.2021.1941252 .

Alpha-amylase is a starch hydrolyzing enzyme which has many industrial applications. In this study, Bacillus subtilis QM3 has ability to produce α-amylase. Identification was done by iodine test, based on the clear zone around the sample in starch agar plates. Alpha-amylase activity was measured using 3,5-dinitrosalicylic acid (DNS). The result showed B. subtilis QM3 can produce α-amylase and activity of α-amylase was 50.58 IU/mL. The study on enzymatic properties was found: the optimum temperature is 70°C, and its stability is high at 30°C - 70°C. The optimum pH is 6.0, and the stability is high under the condition of pH was 6.0 - 7.0. Ca2+, Na+, K+ and Mg2+ promoted the activity of alpha-amylase, and their relative enzyme activities were 130.1%, 118.1%, 115.9% and 110.4% respectively. Fe2+, Zn2+, Cu2+, Mn2+ and EDTA inhibited the activity of alpha-amylase. The relative enzyme activities were 86.1% 77.8%, 67.4%, 64.2% and 48.4% respectively.

2′-Fucosyllactose (2′-FL), a human milk oligosaccharide with confirmed benefits for infant health, is a promising infant formula ingredient. Although Escherichia coli, Saccharomyces cerevisiae, Corynebacterium glutamicum, and Bacillus subtilis have been engineered to produce 2′-FL, their titers and productivities need be improved for economic production. Glucose along with lactose have been used as substrates for producing 2′-FL, but accumulation of by-products due to overflow metabolism of glucose hampered efficient production of 2′-FL regardless of a host strain. To circumvent this problem, we used xylose, which is the second most abundant sugar in plant cell wall hydrolysates and is metabolized through oxidative metabolism, for the production of 2′-FL by engineered yeast. Specifically, we modified an engineered S. cerevisiae strain capable of assimilating xylose to produce 2′-FL from a mixture of xylose and lactose. First, a lactose transporter (Lac12) from Kluyveromyces lactis was introduced. Second, a heterologous 2′-FL biosynthetic pathway consisting of enzymes Gmd, WcaG, and WbgL from Escherichia coli was introduced. Third, we adjusted expression levels of the heterologous genes to maximize 2′-FL production. The resulting engineered yeast produced 25.5 g/L of 2′-FL with a volumetric productivity of 0.35 g/L∙h in a fed-batch fermentation with lactose and xylose feeding to mitigate the glucose repression. Interestingly, the major location of produced 2′-FL by the engineered yeast can be changed using different culture media. While 72% of the produced 2′-FL was secreted when a complex medium was used, 82% of the produced 2′-FL remained inside the cells when a minimal medium was used. As yeast extract is already used as food and animal feed ingredients, 2′-FL enriched yeast extract can be produced cost-effectively using the 2′-FL-accumulating yeast cells.

Methanol crossover through polymer electrolyte membranes (PEMs) is a major concern in fuel cell research. In order to address this problem, a sulfonated poly(fluorenyl ether ketone) (SPFEK)/α-zirconium phosphate (ZrP) nanocomposite membrane containing 2.0 wt. % of ZrP nanosheets was prepared by casting a dimethylacetamide (DMAc) dispersion containing SPFEK and exfoliated ZrP nanosheets. The membrane was characterized and tested as a PEM in a single direct methanol fuel cell (DMFC) at 80 °C. The introduction of ZrP nanosheets improved the oxidative stability and reduced methanol permeability and water uptake of the PEM. The SPFEK/ZrP nanocomposite membrane led to the best cell performance among the single cells using SPFEK/ZrP nanocomposite membrane, SPFEK, and Nafion® 117. The maximum power densities obtained for the cells composed of the above three membranes were 51.3, 41.4, and 43.6 mW/cm2, respectively.

Sulfonated poly(aryl ether) (SPAE) membranes have attracted significant attention as polymer electrolyte membranes due to their superior mechanical properties and low cost. However, the poor chemical stability and methanol barrier property of SPAE membranes limit the fuel cell performance. It is necessary to improve the proton conductivity, methanol barrier property, and stability of SPAE for high-performance fuel cells. Herein, a novel proton conductive filler, sulfonated α-zirconium phosphate (ZrP-SO3H), was synthesized and introduced to sulfonated poly(fluorenyl ether ketone) (SPFEK) to fabricate advanced nanocomposite membranes. The oxidative stability, methanol permeability, water uptake, and proton conductivity of the as-prepared nanocomposite membranes were characterized. The nanocomposite membranes exhibited comparable performance as Nafion® 117 membrane in H2/O2 fuel cell and higher performance than Nafion® 117 in direct methanol fuel cell. These results suggest that ZrP-SO3H-doped SPFEK membrane is a promising candidate as a proton exchange membrane in high-performance fuel cells.

Lipopolysaccharides (LPS)-induced retinal inflammation is an important factor in retinal diseases. This study was aimed to investigate the effect of Sirt6 on LPS-induced retinal injury. ARPE-19 cells were incubated with LPS to induce inflammation. The cell viability was determined using CCK-8 assay. The mRNA level and protein expression of corresponding genes was detected using qRT-PCR and western blot, respectively. The production of inflammatory cytokines was measured using ELISA kit. The levels of oxidative stress-related factors were measured using their detection kits. Cell apoptosis was observed using TUNEL assay. The results showed that Sirt6 was downregulated after LPS treatment. Sirt6 strengthened LPS-induced autophagy by promoting the expression of LC3II/I, beclin1 and ATG5. Sirt6 treatment significantly inhibited LPS-induced inflammation, oxidative stress and cell apoptosis, which was then partly abolished by 3 MA. These results suggest Sirt6 to be an important regulator for LPS-induced inflammation, oxidative stress, and apoptosis partly by regulating cell autophagy.

Submicron phase-change droplets are an emerging class of ultrasound contrast agent. Compared with microbubbles, their relatively small size and increased stability offer the potential to passively extravasate and accumulate in solid tumors through the enhanced permeability and retention effect. Under exposure to sufficiently powerful ultrasound, these droplets can convert into in situ gas microbubbles and thus be used as an extravascular-specific contrast agent. However, in vivo imaging methods to detect extravasated droplets have yet to be established. Here, we develop an ultrasound imaging pulse sequence within diagnostic safety limits to selectively detect droplet extravasation in tumors. Tumor-bearing mice were injected with submicron perfluorobutane droplets and interrogated with our imaging-vaporization-imaging sequence. By use of a pulse subtraction method, median droplet extravasation signal relative to the total signal within the tumor was estimated to be Etumor=37±5% compared with the kidney Ekidney=-2±8% (p < 0.001). This work contributes toward the advancement of volatile phase-shift droplets as a next-generation ultrasound agent for imaging and therapy.

A novel [4+1] spiroannulation of o- & p-bromophenols with α,β-unsaturated imines has been developed for the direct synthesis of a new family of azaspirocyclic molecules. Notably, several other halophenols (X=Cl, I) were also applicable for this transformation. Moreover, a catalytic asymmetric version of the reaction was realized with 1-bromo-2-naphthols by using a chiral ScIII /Py-Box catalyst. Mechanistic studies revealed that this domino reaction proceeded through electrophile-triggered dearomatization of phenol derivatives at their halogenated positions and followed by halogen-displacement with N-nucleophiles via a radical-based SRN 1 mechanism.

Engineering highly porous SiC foams with interconnected cellular architecture and satisfactory compressive strength for the practical applications remains a challenging task. In the current work, SiC foams bonded by in-situ formed mullite phase were fabricated via polyurethane foaming using boehmite sol-coated SiC powder as the raw material. The strategy in the current work endowed the resultant products with ultrahigh porosity, interconnected pore structure, and a robust mullite bonding phase among the SiC particles. The resulting products with this cellular architecture possessed a high porosity level of 88.5% and maintained a robust compressive strength of 2.56 MPa. Our results showed that as-prepared products are promising for practical applications in the filtration, adsorption and catalytic areas.

The design and synthesis of new filtration materials for high-temperature particulate matter capture are of both technological and scientific importance but still remain a challenging task. In the current work, we presented an approach for the manufacturing of highly porous SiC cellular ceramics by combining polyether polyol-modified carbon black with polyurethane foaming method. Hydroxyl groups were introduced to the surface of carbon black to prevent agglomeration. As-obtained SiC cellular ceramic possed three-dimensional interconnected reticular architecture with the abundant micron-sized window on its cell wall. The resulting porous SiC ceramic exhibited a high removal efficiency (95.8%) with extremely low pressure drop (38 Pa). The successful fabrication of such fascinating material may provide new insights for high-temperature particulate matter filtration.

Objective Explored the mechanism of action of tanshinone IIA (TIIA) against atherosclerosis. Methods ApoE mice were divided into two groups of 10: model and TIIA. A control group of 10 wild-type mice was created. ApoE mice were fed a high-fat diet for 12 weeks. The TIIA group received TIIA once daily. Mice were anesthetized, blood collected by cardiac puncture, and the aortic sinus/arch collected for histology and molecular studies, respectively. Results Mice intima in the model group had large areas of plaque formation, serum levels of total cholesterol (TC), triglycerides, and low-density lipoprotein-cholesterol (LDL-C) increased significantly, and high-density lipoprotein-cholesterol (HDL-C) levels decreased significantly in the model group after 12 weeks. Staining [hematoxylin and eosin (H&E), Oil-Red-O] showed that the aorta had lesions, a higher degree of plaque formation, and considerable lipid deposition in model-group mice. After TIIA treatment, expression of HDL-C was increased significantly and that of TC, triglycerides and LDL-C decreased significantly, and plaque size and lipid deposition improved obviously. Analyses of protein phosphorylation in aortic tissue suggested that the transforming growth factor (TGF)-β/phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/endothelial nitric oxide synthase (eNOS) pathway was activated in TIIA-treated mice. Conclusion TIIA can lower levels of serum lipids, stabilize atherosclerotic plaques, reduce endothelial injury, and inflammatory damage by activation of the TGF-β/PI3K/Akt/eNOS pathway.

Adiponectin secretion-promoting compounds have therapeutic potentials in human metabolic diseases. Diallyl biphenyl-type neolignan compounds, magnolol, honokiol, and 4-O-methylhonokiol, from a Magnolia officinalis extract were screened as adiponectin- secretion promoting compounds in the adipogenic differentiation model of human bone marrow mesenchymal stem cells (hBM-MSCs). In a target identification study, magnolol, honokiol, and 4-O-methylhonokiol were elucidated as PPARα and PPARγ dual modulators. Diallyl biphenyl-type neolignans affected the transcription of lipid metabolism-associated genes in a different way compared to those of specific PPAR ligands. The diallyl biphenyl-type neolignan structure provides a novel pharmacophore of PPARα/γ dual modulators, which may have unique therapeutic potentials in diverse metabolic diseases.

A gelcasting system of alumina utilizing tartaric acid as the dispersant and glutaraldehyde as the crosslinker is reported, in which glutaraldehyde can polymerize itself and react with tartaric acid, thus forming a three-dimensional network. Measurement of zeta potential and viscosity shows good dispersion ability of tartaric acid. Shear modulus during gelation demonstrates its good gelation strength and fast gelation speed at room temperature. Moreover, an effective way to control the gelation speed is provided to improve the feasibility of this method. Results indicate that this gelcasting method has the advantages of low viscosity, small amounts of additives and short forming time and is a promising method to fabricate green bodies with large sizes and complex shapes.

Semiconductor ionic electrolytes have obtained much attention because of good ionic conductivity and electrochemical performance. Novel semiconductor ionic NSDC (Ce0.8Sm0.2O2-δ-Na2CO3)-LCCN (LiCo0·225Cu0·075Ni0·7O3-δ) composite materials have been adopted as electrolyte membrane for the first time, in which symmetrical cell composed of NSDC-LCCN membrane is constructed with Ni0·8Co0·15Al0·05LiO2 (NCAl)-pasted Ni foam electrodes. An open circuit voltage (OCV) above 1 V and improved power density are obtained in the NSDC-LCCN cells, which confirms the functionality of the proposed semiconductor ionic materials. Meanwhile, X-ray diffractometer (XRD) and Scanning electron microscope (SEM) analyses identify the phase purity and homogenous nanocomposite morphology of all the NSDC-LCCN materials samples with various mass ratios. The performance illustrated by much more steady instead of transient state evaluation reveals that 3NSDC-LCCN composite electrolyte is most optimum, and the corresponding cell exhibits a considerable maximum power density of 598 mW cm−2 at 550 °C, over five times of that of pure NSDC electrolyte cells. Short-term duration test of 3NSDC-LCCN cell at 550 °C shows that the cell could steadily operate up to ~9 h without obvious degradation at a remarkable current density of 469 mA cm−2, which indicates that NSDC-LCCN composite electrolyte is a promising material for low temperature solid oxide fuel cells.

Cellular ceramics with 3D network architecture are attracting ever-increasing attention because of their great application potential in multiple fields. Unfortunately, a daunting challenge still remains for fabricating such materials. A novel methodology is provided in the current work to construct cellular ZrO2 ceramics with such architecture by combining polyurethane foaming and chemical modification technology. Stearic acid grafted ZrO2 powder with improved dispersibility allows the successful assembly into the polyurethane porous framework. The obtained cellular materials possess a three-dimensional network architecture with windows on the cell wall. The resulting ZrO2 cellular ceramic with such unique structure exhibits a relatively high porosity (83.5%) and robust compressive strength (13.5 MPa), which outperforms most of the existing ZrO2-based counterparts. With above advantages, we envision that as-prepared products are promising for filter applications.

A new gelcasting approach of alumina inspired by Isobam was designed utilizing a polyelectrolyte dispersant named BTT, which is able to form cross-links via thiol-ene reaction with pentaerythritol tetrakis(2-mercaptoacetate). Measurement of zeta potential and viscosity shows good dispersion ability of BTT in 52 vol% alumina suspensions. The flow curves and shear modulus of wet green bodies during gelation demonstrate its high gelation strength in comparison with Isobam. The analysis of effects of addition of ammonium citrate tribasic into the system indicates that a polymer-particle double network is supposed to form during gelation. Elastic part and viscous part of gelation strength of the system are mainly dominated by interaction between polyelectrolyte and particles and cross-linking respectively, which accounts for the existence of both high gelation strength and flexibility of wet green bodies fabricated in this approach.

Conventional approaches on using hydroxylamine derivatives as single nitrogen sources, for the construction of n-membered (n > 3) N-heterocycles, rely upon two chemical operations by involving sequ...

Perovskite and chalcogenide quantum dots (QDs) are important nano semiconductors. It has been a challenge to synthesize heterostructural QDs combining perovskite and chalcogenide with tailorable photoelectronic properties. In this report, heterostructural CsPbX3-PbS (X = Cl, Br, I) QDs were successfully synthesized via a room temperature in situ transformation route. The CsPbX3-PbS QDs show a tunable dual emission feature with the visible and near-infrared (NIR) photoluminescence (PL) corresponding to CsPbX3 and PbS, respectively. Typically, the formation and evolution of the heterostructural CsPbBr3-PbS QDs with reaction time was investigated. Femtosecond transient absorption spectroscopy (TAS) was applied to illuminate the exciton dynamics in CsPbBr3-PbS QDs. The mild synthetic method and TAS proved perovskite to PbS energy transfer may pave the way toward highly efficient QD photovoltaic and optoelectronic devices.

To describe the surgical procedures, outcomes, and complications of a novel technique of subretinal injection of ranibizumab (SRR). Between September 2012 and September 2018, 37 eyes of 26 consecutive children with vascularly active total retinal detachments in 1 or both eyes treated with SRR as primary treatment were included in this retrospective study. All included eyes received subretinal injection of ranibizumab (0.25 mg/ 0.025 ml). Data included demographics, ocular examination, and anatomic outcomes, following treatment and complications of eyes after SRR were collected. Eleven patients had bilateral SRR injections and 15 had monocular SRR injection. Thirteen patients were diagnosed as retinopathy of prematurity. Of all patients, the mean gestational age was 34.5 ± 5.1 weeks (range: 29.6~40.7 weeks), and birth weight was 2328.1 ± 1083.9 g (range: 940~3900 g). On 1-week postoperative follow-up, vascular activity decreased in all 37 eyes (100%). On the 1-month postoperative follow-up, vascular activity decreased but remained in 24 eyes (24/35, 68.6%) of 16 patients and vanished in 11 eyes (11/35, 31.4%) of 9 patients. No eye needed a secondary anti-VEGF therapy. Local subconjunctival hemorrhage was noted in two eyes (2/37, 5.4%). Localized wound leakage of subretinal fluid was also noted in one eye (1/37, 2.7%). In this very limited study, we showed that SRR in vascularly active advanced pediatric vasoproliferative disorders with total retinal detachments is effective and promising, although more extensive controlled trials will be needed to confirm its safety and efficacy.

Palladium-catalyzed alkene-directed cross-coupling of aryl iodide with another aryl halide through C-H arylation opens a unique avenue for unsymmetrical biaryl-derived molecules. However, homo-coupling of aryl iodides often erodes the overall synthetic efficiency. Reported herein is a highly chemoselective Pd0 -catalyzed alkyne-directed cross-coupling of aryl iodides with bromophenols, which was subsequently followed by phenol dearomatization to furnish a very attractive [2+2+1] spiroannulation. Notably, possible homo-coupling of aryl iodides was not observed at all. Mechanistic studies indicated that a five-membered aryl/vinyl palladacycle most likely accounts for promoting the key step of biaryl cross-coupling.

Dithiophosphinic acids (DPAHs, expressed as R1R2PSSH) are a type of sulfur-donor ligand that have been vastly applied in hydrometallurgy. In particular, DPAHs have shown great potential in highly efficient trivalent actinide/lanthanide separation, which is one of the most challenging tasks in separation science and is of great importance for the development of an advanced fuel cycle in nuclear industry. However, DPAHs have been found liable to undergo oxidative degradation in the air, leading to significant reduction in the selectivity of actinide/lanthanide separation. In this work, the atmospheric degradation of five representative DPAH ligands was investigated for the first time over a sufficiently long period (180 days). The oxidative degradation process of DPAHs elucidated by ESI-MS, 31P NMR, and FT-IR analyses is R1R2PSSH → R1R2PSOH → R1R2POOH → R1R2POO–OOPR1R2, R1R2PSSH → R1R2PSS–SSPR1R2, and R1R2PSSH → R1R2PSOH → R1R2POS–SOPR1R2. Meanwhile, the determination of pKa values through pH titration and oxidation product by PXRD further confirms the S → O transformation in the process of DPAH deterioration. DFT calculations suggest that the hydroxyl radical plays the dominant role in the oxidation process of DPAHs and the order in which the oxidation products formed is closely related to the reaction energy barrier. Moreover, nickel salts of DPAHs have shown much higher chemical stability than DPAHs, which was also elaborated through molecular orbital (MO) and adaptive natural density portioning (AdNDP) analyses. This work unambiguously reveals the atmospheric degradation mechanism of DPAHs through both experimental and theoretical approaches. At the application level, the results not only provide an effective way to preserve DPAHs but could also guide the design of more stable sulfur-donor ligands in the future.

The antioxidant properties of coumestans have been investigated previously using inappropriate methods, which has resulted in misleading and inaccurate mechanisms being reported to account for their antioxidant behavior. In this study, the phenolic coumestan wedelolactone increased the viability of OH -treated mesenchymal stem cells (MSCs) in a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl assay. Mechanistic analysis in vitro suggested that wedelolactone could scavenge various radicals, including OH , O 2 - , 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) and 1,1-diphenyl-2-picrylhydrazyl ( DPPH ) radicals, as well as reducing Cu2+ and chelating Fe2+. Configuration analysis based on a ball and stick model indicated that the 3′,4′-catechol moiety of wedelolactone was acting as an Fe2+-chelating site. The main product of the reaction between wedelolactone and DPPH was analyzed by ultra-performance liquid chromatography electrospray ionization quadrupole time-of-flight tandem mass spectrometry, which gave a mass ion with an m/z value of 709. This peak yielded several fragments with m/z values of 663, 543, 501 and 483. Quantitative evaluation revealed that the antioxidant activity of wedelolactone was 1.62 times higher than that of Trolox. Based on these results, we concluded that (i) wedelolactone can efficiently protect MSCs against OH -induced damage and that this protective effect provides preliminary evidence for the application of wedelolactone in transplantation of MSCs (especially for osteoporosis); (ii) the main antioxidant mechanism of wedelolactone involves direct radical-scavenging via a single electron transfer (SET) → radical adduct formation (RAF) pathway, whereas the Fe2+-chelating activity of wedelolactone represents a minor pathway; and (iii) the direct radical-scavenging and Fe2+-chelating pathways can both be attributed to the catechol moiety rather than the coumestan skeleton.

Combined therapy provides a more effective method in the treatment of tumors and becomes a research hotspot. To improve treatment outcomes and reduce serious side effects, hydrogel-based local delivery was developed herein to form a drug depot in suit to eliminate tumors. Indocyanine green and imiquimod were coencapsulated in the novel temperature-sensitive chitosan hydrogel. After intratumoral injection of the hydrogel, indocyanine green that accumulated in the tumor area could induce thermal ablation of primary tumors under laser irradiation. In the presence of imiquimod, the immune effects increased the probability of complete ablation of primary tumors and inhibition of metastases. Combined with cyclophosphamide, the enhanced immunological responses would further inhibit tumors and prolong the survival time. In a word, this work offered an excellent local delivery platform that enabled a remarkable combined antitumor strategy and achieved synergistic therapeutic effects.

Background: Chronic alcohol consumption induces lipophagy retard which contributes the pathogenesis of liver steatosis. Lipophagy-related Rab7 responsible for the fusion between autophagosomes and lysosomes has been presumed as a crucial regulator on the progression of alcohol liver disease (ALD) despite elusive mechanisms. More importantly, whether hepatoprotective quercetin targets Rab7-associated lipophagy disorder or not, still remains uncertain. Results: ALD mice were induced by chronic-plus-single-binge ethanol feeding that manifested by hampering autophagosomes formation with lipid droplets (LDs) and fuse with lysosomes compared with the normal control, which was normalized partially by quercetin. GST-RILP pulldown assay of Rab7 indicated an improved GTP-Rab7 as quercetin treatment for ethanol-feeding mice. Lipophagy was blocked when HepG2 cells were transfected with siRNA-Rab7, which was reversed through co-transfection of Rab7Wt plasmid. Rab7-specific inhibitor CID1067700 aggravated ethanol-induced steatosis and autophagic flux disruption visualized by immunofluorescence co-localization analysis and mCherry-GFP-LC3 transfection. HepG2 cells overexpressing Rab7Wt show a stronger alleviation on alcohol-induced lipophagy dysfunction than Rab7Q67L. Furthermore, TBC1D5 responsible for Rab7 inactivation was downregulated after alcohol administration, but regained by quercetin. Rab7 circulation retarded by ethanol and corrected by quercetin was further revealed by fluorescence recovery after photobleaching (FRAP). Conclusions: Chronic alcoholic not only inactivates Rab7 but also retards TBC1D5-mediated Rab7 turnover, synergistically obstructing lipophagy flux and promoting ethanol-induced steatosis. Quercetin attenuates adipohepatic degeneration by normalizing ethanol-imposed Rab7 disorders and subsequent lipophagy disturbance, highlighting a novel mechanism and promising prospect of quercetin-like phytochemicals against the crucial first hit from the alcohol.

Simultaneous co-fermentation of glucose and xylose is a key desired trait of engineered Saccharomyces cerevisiae for efficient and rapid production of biofuels and chemicals. However, glucose strongly inhibits xylose transport by endogenous hexose transporters of S. cerevisiae. We identified structurally distant sugar transporters (Lipomyces starkeyi LST1_205437 and Arabidopsis thaliana AtSWEET7) capable of co-transporting glucose and xylose from previously unexplored oleaginous yeasts and plants. Kinetic analysis showed that LST1_205437 had lenient glucose inhibition on xylose transport and AtSWEET7 transported glucose and xylose simultaneously with no inhibition. Modelling studies of LST1_205437 revealed that Ala335 residue at sugar binding site can accommodates both glucose and xylose. Docking studies with AtSWEET7 revealed that Trp59, Trp183, Asn145 and Asn179 residues stabilized the sugars, allowing both xylose and glucose to be co-transported. In addition, we altered sugar preference of LST1_205437 by single amino acid mutation at Asn365. Our findings provide a new mechanistic insight on glucose and xylose transport mechanism of sugar transporters and the identified sugar transporters can be employed to develop engineered yeast strains for producing cellulosic biofuels and chemicals. This article is protected by copyright. All rights reserved.

The proliferation of chimeric antigen receptor (CAR) T cells is closely related to their efficacy, but it is still a great challenge to monitor and quantify CAR T cells in vivo. Based on the high affinity (Kd ≈ 10−15 M) of streptavidin (SA) and biotin, radiolabeled biotin may be used to quantify SA-transduced CAR T cells (SA-CAR T cells). Radio-thin-layer chromatography (radio-TLC) and positron emission tomography (PET) are highly sensitive for trace analysis. Our aim was to develop radio-TLC and PET methods to quantify SA-CAR T cells in vitro and in vivo. First, we developed [68Ga]-DOTA-biotin. Commercially available SA was used as a standard, and quantitative standard curves were established in vitro and in vivo by radio-TLC and PET. Furthermore, the feasibility of the method was verified in Raji model mice. The linear range of radio-TLC was 0.02 ∼ 0.15 pmol/μL with R2 = 0.9993 in vitro. The linear range of PET was 0.02 ∼ 0.76 pmol/μL with R2 = 0.9986 in vivo. SA in CAR T cells can also be accurately quantified in a Raji leukemia model according to PET imaging. The radio-TLC/PET method established in this study is promising for using in the dynamic monitoring and analysis of SA-CAR T cells during therapy.

In this work, the PVDF/glass as-prepared composite membrane was prepared through phase-inversion method and used to adsorb methylene blue dye. The results of SEM and BET showed that the membrane had an asymmetric nanoscale porous structure. The electronegativity on the surface of membrane was determined through zeta potential test. The adsorption properties of as-prepared composite membrane and glass membrane were studied through testing the removal ratio of methylene blue from aqueous solution. Then the effects of membranes dose, pH value, temperature and initial concentration on the removal ratio were systematically studied. The adsorption mechanism was also studied. The adsorption kinetics and adsorption isotherm fitted well with the pseudo-second-order model and Freundlich model, respectively. In addition, the adsorption efficiency of glass membrane basically remained 85% after eight repeated adsorption-calcination cycles. The obtained membranes could be reused for methylene blue removal with high efficiency for multiply times.

Background and Objectives Tracking of the tumor progression by MSCs-based therapy is being increasingly important in evaluating relative therapy effectively. Herein, Bioluminescence imaging (BLI) technology was used to dynamically and quantitatively track the hepatocellular carcinoma suppressive effects by human umbilical cord mesenchymal stem cells (UC-MSCs). Methods and Results The stem cells present typical phenotypic characteristics and differentiation ability by morphology and flow cytometry analysis of marker expression. Then, the growth inhibition effect of conditioned medium and UC-MSC on H7402 cells was studied. It is found both the conditioned medium and UC-MSC can effectively decrease the proliferation of H7402 cells compared with the control group. Meanwhile, the relative migration of UC-MSC to H7402 is also increased through the transwell migration assay. In addition, a mice hepatoma tumor model was built by H7402 cells which can express a pLenti-6.3/DEST-CMV-luciferase 2-mKate2 gene. The effect of stem cells on growth inhibition of tumor in a mice transplantation model was dynamically monitored by bioluminescence imaging within 5 weeks. It has shown the bioluminescence signal intensity of the tumor model was significantly higher than that of the UC-MSC co-acting tumor model, indicating that the inhibition of UC-MSC on liver cancer resulted in low expression of bioluminescent signals. Conclusions The microenvironment of UC-MSCs can effectively inhibit the growth of liver cancer cells, and this therapeutic effect can be dynamically and quantitatively monitored in vivo by BLI. This is of great significance for the imaging research and application of stem cells in anticancer therapy.

The first isolable Ge5-spiropentadiene 1 was synthesized via the reduction of (iPr3Si)2NGeCl (3) with potassium. The crystal structure of 1 reveals a spirocyclic Ge5 skeleton containing two Ge-Ge double bonds (avg. 2.34 A), which are fettered in two Ge3 rings with a dihedral angle of 70.193°. The DFT calculations and orbital analysis show that the σ-delocalization of the Ge5 skeleton and the 2π-delocalized aromatic Ge3 rings enhance the stability of molecule 1.

The investigation of high-nitrogen compounds has been significant for the evolution of energetic materials. Azo-bis-1,2,4-triazole (aTRz) can be an excellent energetic backbone, owing to its charac...

We introduce a colorimetric as well as fluorometric dual response CO-releasing molecule as Mn(I) tricarbonyl complex with a nitrobenzoxadiazole (NBD) fluorophore. DFT and TD-DFT studies corroborate that extended conjugation in the principal ligand frame will help to release CO at low energy radiation. A very low toxicity of NBD-CORM was observed against LX-2 and HepaRG® human cell lines.