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In vivo levels of reactive oxygen species (ROS) and reactive nitrogen species (RNS) are critical to many physiological and pathological processes. Because of the distinct differences in their biological generation and effects, simultaneously visualizing both of them could help deepen our insights into the mechanistic details of these processes. However, real-time and deep-tissue imaging and differentiation of ROS- and RNS-related molecular events in living subjects still remain a challenge. Here, we report the development of two activatable 19F magnetic resonance imaging (MRI) molecular probes with different 19F chemical shifts and specific responsive behaviors for simultaneous in vivo detection and deep-tissue imaging of O2•- and ONOO-. These probes are capable of real-time visualization and differentiation of O2•- and ONOO- in living mice with drug-induced acute kidney injury by interference-free multiplexed hot-spot 19F MRI, illustrating the potential of this technique for background-free real-time imaging of diverse biological processes, accurate diagnosis of various diseases in deep tissues, and rapid toxicity evaluation of assorted drugs.

Densely functionalized chiral nitrogen-containing heterocycles are ubiquitous in bioactive synthetic compounds and natural products. Herein, we report a nickel (Ni)-catalyzed enantioselective desym...

GSH-mediated liver biotransformation is a crucial physiological process demanding efficient research tools. Here, we report a type of amorphous FexMnyO nanoparticles (AFMO-ZDS NPs) as redox-activated probes for in vivo visualization of the dynamics of GSH-mediated biotransformation in liver with T1-weighted magnetic resonance imaging (MRI). This imaging technique reveals the periodic variations in GSH concentration during the degradation of AFMO-ZDS NPs due to the limited transportation capacity of GSH carriers in the course of GSH efflux from hepatocytes to perisinusoidal space, providing direct imaging evidence for this important carrier-mediated process during GSH-mediated biotransformation. Therefore, this technique offers an effective method for in-depth investigations of GSH-related biological processes in liver under various conditions as well as a feasible means for the real-time assessment of liver functions, which is highly desirable for early diagnosis of liver diseases and prompt a toxicity evaluation of pharmaceuticals.

A novel ferrate(VI)/titanium dioxide/ultraviolet [Fe(VI)/TiO2/UV] system was successfully established for the photocatalytic oxidation of dimethyl phthalate (DMP). This system demonstrated a higher removal efficiency of DMP (95.2%) than the conventional TiO2/UV and Fe(VI) alone systems (51.8% and 23.5%, respectively) and produced obvious synergistic effects. Response surface methodology (RSM), based on a three level, three independent variables design, was conducted through Design Expert 8.0.6 program, and a second-order polynomial model (R2 = 0.998) was developed to quantitatively describe the photocatalysis of TiO2 combined with Fe(VI) oxidation under ultraviolet irradiation. The fresh TiO2 and photochemical reacted Fe(VI)/TiO2 were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and element dispersive spectrum (EDS), which indicated that Fe(VI) was imprinted into the TiO2, and the surface adsorbed Fe-O-(organic) materials inhibited DMP degradation. This photocatalytic oxidant showed high activity and stability after nine cycles without loss of its effectiveness (counting from the second cycle). The intermediates/products of DMP were analyzed by gas chromatography-mass spectrometry. The proposed pathway for DMP degradation involved one electron transfer of hydroxyl radical and breaking of the ester bond and benzene ring. The mineralization efficiencies of DMP in actual industrial wastewater and simulated water were 87.1% and 95.2%, respectively, suggesting practical field applications. A ecotoxicity test (17.3% inhibition on bioluminescence) in treating actual industrial wastewater containing DMP implied that the proposed Fe(VI)/TiO2/UV had a potential for industrial water treatment.

Bioenergy crops provide enormous renewable biomass resources convertible for biofuel production, but lignocellulose recalcitrance fundamentally determines its enzymatic saccharification at high cost and low efficiency. In this study, total 30 diverse Miscanthus lignocellulose substrates were incubated with T. reesei strain to secret lignocellulose-degradation enzymes, and their major wall polymers features (cellulose crystallinity, hemicellulose arabinose and lignin H-monomer) were meanwhile examined with distinct impacts on the enzyme activities. Using characteristic Miscanthus (Msi62) de-lignin residue as inducing substrate with the reesei strain, this study detected that the Msi62-induced enzymes were of consistently higher enhancements on enzymatic saccharification of various lignocellulose residues examined in 17 grassy and woody bioenergy crops, particularly for the hemicellulose hydrolyses, compared to other two reesei-secreted cellulases and three commercial enzymes. Notably, based on SDS-gel protein separation profiling and LC-MS/MS analysis, the Msi62-induced enzymes consist of distinct cellulases (CBHI, BG, EGII) compositions and high-activity xylanases. Therefore, this study has demonstrated an applicable approach to achieve the optimal cellulases and xylanases cocktails that enable for low-costly and high-efficient enzymatic saccharification of diverse lignocellulose sources, providing a potential strategy for large-scale biofuel production in all major bioenergy crops.

The prompt recombination between photogenerated electrons and holes is the common problem for improving the hydrogen evolution performance of a photocatalyst, which could be solved greatly by composite co-catalysis. Herein, a simple hydrothermal reaction was utilized to prepare g-C3N4/Ni9S8 composite photocatalysts. Through electroless nickel plating, Ni9S8 nanostructure was homogeneously grown onto the g-C3N4 surface by using sodium hypophosphite as reducing agent. With the optimum loading amount of Ni9S8, the acquired composite, compared with the raw g-C3N4, presented a significant increase in hydrogen evolution rate under visible light irradiation, which was measured as 355.7 μmol g−1 h−1 at 7 °C, being 21.2 times that of raw g-C3N4. The mechanism for the hydrogen evolution reaction over the present g-C3N4/Ni9S8 composite photocatalysts was discussed in detail.

Background. The decrease in asialoglycoprotein receptor (ASGPR) levels is observed in patients with chronic liver disease and liver tumor. The aim of our study was to develop ASGPR-targeted superparamagnetic perfluorooctylbromide nanoparticles (M-PFONP) and wonder whether this composite agent could target buffalo rat liver (BRL) cells in vitro and could improve R2 ∗ value of the rat liver parenchyma after its injection in vivo. Methods. GalPLL, a ligand of ASGPR, was synthesized by reductive amination. ASGPR-targeted M-PFOBNP was prepared by a film hydration method coupled with sonication. Several analytical methods were used to investigate the characterization and safety of the contrast agent in vitro. The in vivo MR T2 ∗ mapping was performed to evaluate the enhancement effect in rat liver. Results. The optimum concentration of Fe3O4 nanoparticles inclusion in GalPLL/M-PFOBNP was about 52.79 µg/mL, and the mean size was 285.6 ± 4.6 nm. The specificity of GalPLL/M-PFOBNP for ASGPR was confirmed by incubation experiment with fluorescence microscopy. The methyl thiazolyl tetrazolium (MTT) test showed that there was no significant difference in the optical density (OD) of cells incubated with all GalPLL/M-PFOBNP concentrations. Compared with M-PFOBNP, the increase in R2 ∗ value of the rat liver parenchyma after GalPLL/M-PFOBNP injection was higher. Conclusions. GalPLL/M-PFOBNP may potentially serve as a liver-targeted contrast agent for MR receptor imaging.

Aim of this study was to evaluate the association between multiple essential microelements exposure and the aggressive clinicopathologic characteristics of papillary thyroid carcinoma (PTC). The concentrations of 10 essential microelements in urine [cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), selenium (Se), strontium (Sr), zinc (Zn), and iodine (I)] were measured in 608 patients newly diagnosed with PTC, including 154 males and 454 females. Chi square test and Wilcoxon rank sum test were used to compare general characteristics among males and females. Multivariate logistic regression was used to evaluate the associations between essential microelements and PTC clinicopathologic characteristics in single- and multi-microelement models. In this study, we only observed that the frequency of lymph node metastasis in males was higher than in females, and males had higher levels of zinc than females, but males had lower levels of iodine than females. It was found that high levels of Fe were associated with decreased risk of PTC tumor size > 1 cm, capsular invasion, and advanced T stage (T3/4a/4b). High levels of Co and Mo were associated with decreased risk of capsular invasion and lymph node metastasis, respectively. However, high levels of Mn and Sr were associated with increased risk of capsular invasion and multifocality respectively, and both were associated with increased risk of advanced T stage (T3/4a/4b). These findings indicated that certain essential microelements might have potential effects on PTC progression and aggressiveness. Further studies are required to confirm these findings.

The overexpression of HIF-1α in solid tumors due to hypoxia is closely related to drug resistance and consequent treatment failure. Herein, we constructed a hypoxia-activated prodrug named as YC-Dox. This prodrug could be activated under hypoxic conditions and undergo self-immolation to release doxorubicin (Dox) and YC-1 hemisuccinate (YCH-1), which could execute chemotherapy and result in HIF-1α downregulation, respectively. This prodrug is capable of specifically releasing Dox and YCH-1 in response to hypoxia, leading to a substantial synergistic potency and a remarkable cytotoxic selectivity (>8-fold) for hypoxic cancer cells over normoxic healthy cells. The in vivo experiments reveal that this prodrug can selectively aim at hypoxic cancer cells and avoid undesired targeting of normal cells, leading to elevated therapeutic efficacy for tumor treatment and minimized adverse effects on normal tissues.

Chitosan is a biodegradable, biocompatible, and nontoxic aminopolysaccharide. This review summarizes and discusses the structural modifications, including substitution, grafting copolymerization, cross-linking, and hydrolysis, utilized to improve the physicochemical properties and enhance the bioactivity and functionality of chitosan and related materials. This manuscript also reviews the current progress and potential of chitosan and its derivatives in body-weight management and antihyperlipidemic, antihyperglycemic, antihypertensive, antimicrobial antioxidant, anti-inflammatory, and immunostimulatory activities as well as their ability to interact with gut microbiota. In addition, the potential of chitosan and its derivatives as functional ingredients in food systems, such as film and coating materials, and delivery systems is discussed. This manuscript aims to provide up-to-date information to stimulate future discussion and research to promote the value-added utilization of chitosan in improving the safety, quality, nutritional value and health benefits, and sustainability of our food system while reducing the environmental hazards.

Ag/AgCl/ZnTiO3 nanohybrids were assembled by the photoreduction–precipitation assisted with ultrasonic method. Rhodamine B (RhB), methylene blue (MB) and methyl orange (MO) were selected to evaluate the photocatalytic performance of Ag/AgCl/ZnTiO3 nanohybrids, and the effects of operating conditions (photocatalyst dosage, dye concentration and pH) were further studied. The photocatalytic debasement of Ag/AgCl/ZnTiO3 for RhB, MB and MO reached 99%, 98% and 95% under UV light (365 nm) for 30 min, respectively, while decreased to 90%, 88% and 73% under visible light (> 420 nm). In comparison with the pure ZnTiO3, the degradation of RhB, MB and MO by Ag/AgCl/ZnTiO3 under UV light increased 14.09-fold, 3.16-fold and 6.18-fold, respectively. Based on UV–visible absorption spectra and photoluminescence spectra, the photocatalytic activity of Ag/AgCl/ZnTiO3 nanoparticles was enhanced by surface plasmon resonance (SPR) and efficient interchange between photogenerated electrons and holes. After five cycling experiments, the degradation ability of Ag/AgCl/ZnTiO3 nanoparticles descended less than 10% and the physicochemical features almost unchanged, which indicated that these hybrid photocatalysts exhibited favorable durability and stability. Moreover, an enhancement photocatalytic mechanism of Ag/AgCl/ZnTiO3 photocatalysts was proposed by band gap analysis and trapping experiments.

A visible-light-induced direct α-oxygenation of N-substituted 1,2,3,4-tetrahydroisoquinoline derivatives has been successfully developed. Tetraphenylporphyrinatozinc(II) has been identified as an effective and inexpensive photocatalyst for this transformation with a wide range of substrates. This protocol provides a convenient route to the desired products in moderate to good yields at room temperature under air.

In this work, novel Ni3Se2 nanowires are synthesized in situ on the surface of nickel foam (Ni3Se2 NWs@NF) through a one-step hydrothermal reaction under different reaction times, and they demonstrate excellent energy storage performance for hybrid supercapacitors (HSCs). Owing to their good electron transfer capability and porous and hierarchical architecture, the as-prepared Ni3Se2 NWs@NF shows a high capacity of 2.6 C cm−2 at 5 mA cm−2 in a three-electrode cell. Even if the current density increases up to 250 mA cm−2, its specific capacity still remains at 0.93 C cm−2, exhibiting excellent rate capability. Furthermore, an HSC was assembled with the as-prepared Ni3Se2 NWs@NF as the positive electrode and activated carbon (AC) as the negative electrode, in 2 M KOH aqueous electrolyte. The Ni3Se2 NWs@NF//AC HSC demonstrates a high energy density of 64.4 W h kg−1 at a power density of 446.8 W kg−1 at 0.43 A g−1 with an extended voltage of 1.6 V, along with outstanding long-term cycling stability that retains 93.9% of the initial capacity after 10 000 cycles. To the best of our knowledge, the Ni3Se2 NWs@NF//AC HSC developed in this work demonstrates the best capacity performance among the reported HSCs with nickel selenides as electrode materials in aqueous electrolytes. Our results manifest that the Ni3Se2 NWs@NF is a promising electrode material for high-performance HSCs.

Peroxynitrite is an important biomarker for assessing drug-induced liver injury (DILI), which is critical for the development and use of drugs. Herein, we report the development of peroxynitrite-responsive self-assembled 19F MRI nanoprobes, which enable the sensitive imaging of peroxynitrite in L02 cells subjected to oxidative stress and living mice with DILI.

Real-time monitoring of leaf nitrogen (N) content by remote sensing can accurately diagnose crop nutrient status and facilitate precision N management. However, the methods used to estimate of vertically integrated leaf N content do not consider different cropping systems, in which the maize growth stages are not synchronized, resulting in decreased practical value of the results. The purpose of this study was to propose an optimized red-edge absorption area (OREA) index in which the prediction accuracy of vertically integrated leaf N content is improved within spring- and summer-sown maize canopies. The results showed that vertical distributions of N existed regardless of variations in the maize growth stages, that is, the leaf N density of the upper and middle layers was higher than that of the lower layers. These published vegetation indices (VIs) provided relatively good correlations with leaf N density at different layers across all of the datasets. When predicting leaf N density of each leaf layer, an optimal VI is generated, and inconsistent VIs will limit its practical application. To further overcome the drawbacks of the inconsistency of each VI when estimating the leaf N density at different layers, a new OREA index was proposed based on red-edge absorption area parameter. The OREA index showed the highest prediction accuracy with leaf N density for entire canopies (r2 = 0.811, RMSE = 0.374, RE = 13.17%) and canopies without top first leaves (r2 = 0.795, RMSE = 0.269, RE = 15.20%) compared with the other published VIs. It is concluded that the vertically integrated leaf N content under different field experiments can be accurately estimated by the OREA index.

Background Phospholipids, the main lipid component in marine shellfish, mainly comprise glycerophosphocholine (GPC) and glycerophosphoethanolamine (GPE). GPC and GPE in marine shellfish, especially scallop, carry n-3 long-chain polyunsaturated fatty acids, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), although different types of glycerophospholipids (GP) have different health benefits on human health. Moreover, different GP subclasses such as GPC and GPE have different oxidative susceptibilities in complex food systems. The present study compared the oxidative susceptibilities of GPC and GPE in dried scallop during storage by high-performance liquid chromatography-tandem mass spectrometry and kinetic models, and also investigated the effects of natural phenolic antioxidant on their susceptibilities. Results The results showed that GPC and GPE molecular species (carrying EPA or DHA) contents in samples continuously reduced during storage at two different temperatures. The first-order kinetic model better reflected the changes of GPC and GPE molecular species (carrying EPA or DHA) in samples than the zero-order kinetic model during storage. According to the oxidation rate (k) obtained from first-order kinetic models, GPE possessed a greater oxidation rate than GPC during storage. Moreover, the results showed that antioxidants of bamboo leaves (AOB, polar polyphenolic antioxidants) significantly decreased the oxidation rates of GPC and GPE molecular species (carrying EPA or DHA) in samples during storage, and GPC could be more effectively protected by AOB compared to GPE. Conclusion The present study provides a practical method for accurately evaluating the oxidative susceptibility of different phospholipid classes in complex food systems. © 2020 Society of Chemical Industry.

Background Bladder cancer (BC) is a common malignancy worldwide that accounts for 3% of global cancer diagnoses. Chemotherapy resistance limits the therapeutic effect of chemotherapeutic agents in patients with BC. Prolyl 4-hydroxylase, beta polypeptide (P4HB) is an endoplasmic reticulum (ER) chaperone that is upregulated in bladder cancer tissues (The Cancer Genome Atlas, TCGA datasets). Knockdown or suppression of P4HB exerts anticancer activity and sensitizes cells to chemotherapy in various types of cancer. Purpose We aimed to investigate whether the inhibition of P4HB enhances the anticancer efficacy of gemcitabine (GEM) in BC cells and to study the underlying molecular mechanisms. Patients and Methods The P4HB mRNA expression levels of 411 BC patients from the TCGA database and P4HB expression level of eighty BC paraffin-embedded samples detected by immunohistochemistry (IHC) staining were used for clinical feature and prognostic analyses. Bioinformatics analysis was utilized for the mechanistic investigation. Highly P4HB-expressed BC cell lines (T24 and 5637) treated with P4HB inhibitor (Bacitracin, BAC) were used to study the effects of BAC on the sensitivity of BC cells to GEM and the potential mechanism. P4HB inhibition experiments were performed in highly P4HB-expressed BC cells, and cell viability, colony formation, cell cycle, reactive oxygen species (ROS), apoptosis and pathway proteins were assessed in T24 and 5637 cells. Results Western blot analysis showed that P4HB expression was significantly higher in BC tissues than in paired normal tissues. IHC showed that patients with high P4HB expression had a poorer overall survival (OS) rate than those with low P4HB expression. Furthermore, increased P4HB expression was demonstrated to be an independent prognostic marker for BC. Functionally, P4HB inhibition by BAC decreased the cell proliferation ability in vitro. Moreover, BAC treatment sensitized BC cells to GEM. Molecular mechanism analysis indicated that inhibition of P4HB by BAC treatment enhanced the anticancer effects of GEM through increasing cellular ROS content and promoting cell apoptosis and PERK/eIF2α/ATF4/CHOP signaling. Conclusion High P4HB expression was significantly correlated with poor prognosis in BC patients. Inhibition of P4HB by BAC decreased the cell proliferation ability and sensitized BC cells to GEM by activating apoptosis and the PERK/eIF2α/ATF4/CHOP pathways.

Nanofiltration (NF) membranes have attracted significant attention owing to their widespread applications in water treatment and seawater desalination. However, challenges still remain in improving...

Crystalline coordination complexes of actinides, especially in atypical oxidation states, are not only fundamentally important for expanding the notably limited knowledge on the bonding nature of a...

Dental caries is a chronic disease with multiple bacterial infections, Streptococcus mutans is the main cariogenic bacteria. Trollius chinensis Bunge is a common folk medicine in the Xinjiang area of China. In this study, we investigated the total flavonoid content and total phenol content in four types of T. chinensis Bunge extracts and the inhibitory effects of these extracts on S. mutans. Agar diffusion method was used to measure the inhibition zone diameters, and the minimum inhibitory concentration and minimum bactericidal concentration were determined by the twofold dilution method. Water extracts from T. chinensis Bunge and ethanol (30, 60, and 90%) extracts at different concentrations could significantly inhibit the growth of S. mutans. Among them, 30% ethanol extract exhibited the best antibacterial and antibiofilms effect. Biofilm research (crystal violet staining and CLSM) showed that 30% ethanol extract of T. chinensis Bunge plays an important role in inhibiting S. mutans growth and the number of biofilms. The results indicate that T. chinensis Bunge extract has good antibacterial and anti-biofilm activity on S. mutans. It has the potential to be developed for the treatment of caries in clinical application.

Carbonation of concrete is a process which absorbs carbon dioxide (CO2). Recycled aggregate concrete (RAC) may own greater potential in CO2 uptake due to the faster carbonation rate than natural aggregate concrete (NAC). A quantitative model was employed to predict the CO2 uptake of RAC in this study. The carbonation of RAC and the specific surface area of recycled coarse aggregates (RCAs) were tested to verify accuracy of the quantitative model. Based on the verified model, results show that the CO2 uptake capacity increases with the increase of RCA replacement percentage. The CO2 uptake amount of 1 m3 C30 RAC within 50 years is 10.6, 13.8, 17.2, and 22.4 kg when the RCA replacement percentage is 30%, 50%, 70%, and 100%, respectively. The CO2 uptake by RCAs is remarkable and reaches 35.8%–64.3% of the total CO2 uptake by RAC when the RCA storage time being 30 days. Considering the fact that the amount of old hardened cement paste in RCAs is limited, there is an upper limit for the CO2 uptake of RCAs.

In this paper, three diiron butane-1,2-dithiolate complexes have been prepared and characterized. Treatment of the starting complex [Fe2(CO)6{µ-SCH2CH(CH2CH3)S}] (1) with a monophosphine ligand tri...

BACKGROUND: During the synthesis of isopropyl alcohol (IPA) by hydration of propylene, diisopropyl ether (DIPE) is usually produced as a by‐product. Because IPA and DIPE can form a binary homogeneous azeotrope with the minimum boiling temperature at atmospheric pressure, it is difficult to separate the binary mixture by simple distillation. RESULT: For separating the azeotrope IPA + DIPE, side‐stream extractive distillation column (SSED) and extractive dividing wall column (EDWC) processes with three entrainers [2‐methoxyethanol (2‐MEA), 2‐ethoxyethanol and propylene glycol ethyl ether (PGEE)] were simulated and optimized based on the minimal total annual cost (TAC). Moreover, CO₂ emissions of the six sequences were calculated and the impact on the environment evaluated. CONCLUSIONS: The sequence of SSED with PGEE as entrainer can reduce TAC by ≤34.48%, but EDWC with PGEE can offer TAC reduction of ≤52.46%. The results demonstrate that the EDWC sequence with PGEE as entrainer is favourable for separating the binary azeotrope IPA + DIPE. © 2020 Society of Chemical Industry

Treatment of the starting complex [Fe2(CO)6{μ-SCH2CH(CH2OH)S}] (1) with 2-(diphenylphosphino)benzoic acid in the presence of N,N’-dicyclohexylcarbodiimide and 4-dimethylaminopyridine gave the corre...

The crystal structures of the antimicrobial drug tinidazole [TNZ; systematic name: 1-(2-ethylsulfonylethyl)-2-methyl-5-nitroimidazole, C8H13N3O4S] and the 1:1 cocrystal of TNZ with the naturally occurring compound vanillic acid (VA; systematic name: 4-hydroxy-3-methoxybenzoic acid, C8H8O4), namely, the TNZ–VA cocrystal, were determined by single-crystal X-ray analysis at 100 K. The supramolecular structure of the TNZ–VA cocrystal is composed of a carboxylic acid dimer and an O—H...N(heterocycle) synthon in the form of layers made up of O—H...N and O—H...O hydrogen bonds. The layers are joined via C—H...O hydrogen bonds, π–π stacking and C—H...π interactions. The energy framework analysis, together with interaction energy calculations using the DLPNO-CCSD(T) method, indicates that the TNZ–VA cocrystal inherits strong interactions from the TNZ and VA crystals, which accounts for the enhanced thermal stability and reduced dissolution rate. To the best of our knowledge, this is the first example of a cocrystal containing TNZ.

Griseofulvin (GSF) is an antifungal drug that has been clinically used for six decades. Here, we present a rich polymorphism of GSF crystallizing from GSF dispersions with polyethylene glycol (PEG), including five true polymorphs (Forms I-V) and one inclusion complex (IC). Two new polymorphs were reported for the first time, denoted Forms IV and V. Single-crystal structures of new polymorphs and a GSF-PEG IC were determined by X-ray crystallography using single crystals cultivated by microdroplet melt crystallization. A comprehensive solid form landscape of GSF is established to describe phase conversions between polymorphs. Enhancement in molecular mobility by PEG is suggested to be the reason for the nucleation of two new polymorphs, while the small geographic radius of PEG is attributed to the formation of a GSF-PEG IC increasing the density and lowering the Gibbs free energy of the system. This work expands our understanding of the complicated crystallization behavior of GSF in dispersions with PEG and emphasizes the importance of polymorphism control during the manufacturing and storage of PEG-based solid dispersions to achieve reproducible and consistent pharmaceutical performance. The results also suggest that polymer addition is an alternative strategy that cannot be neglected in polymorphism screening.

Glass frit has emerged recently as a promising material for incorporation in adhesive of electronic components owing to its high sealing density, environmental stability and easy processing. This requires the glass surface to be hydrophobic to ensure high dispersity, grinding uniformity, and high-temperature sintering performance of the glass frit. However, the glass surface is usually hydrophilic. In this work, we developed a wet milling method to effectively produce hydrophobic glass powder by using aliphatic chemicals modification. We employed a series of aliphatic chemicals containing nucleophilic functional groups to prepare ultrafine lead aluminosilicate electronic glass powders. The nucleophilic substitution reaction of amino groups, carboxylic acid groups, hydroxyl groups and phosphoric acid groups reduces the hydroxyl content on the surface of the glass powder to 0.10 mg/m2, and generates steric hindrance and hydrophobicity (contact angle: 153.0°) through the long carbon chain. The obtained powder therefore shows a uniform particle size distribution, anti-agglomerated property, and maximum 25 °C lower hemispheric point temperature compared to powder prepared by conventional hydrophilic milling method. This work provides a versatile method to simultaneously control the structural and surface properties of glass powders at their formation stage.

Understanding the genetic basis of trait variations and their coordination between relative species or populations distributing in different environmental conditions is important in evolutionary biology. In marine ectotherms, growth-defense trade-offs are a common ecological and evolutionary phenomenon. However, the biochemical and molecular mechanisms that govern these trade-offs in marine ectotherms in the evolutionary perspective remain poorly investigated. Oysters are among the most important species in global aquaculture. Crassostrea gigas (C. gigas) and Crassostrea angulata (C. angulata) are two allopatric congeneric dominant oyster species that inhabit the northern and southern intertidal areas of China. Wild C. gigas and C. angulata were spawned, and their F1 progeny were cultured in the same sites to reduce the environmental effects. Untargeted metabolomics and transcriptomics, together with phenotypic parameters including morphological traits (growth performance), nutritional content (glycogen, crude fat, and fatty acid content), physiology (normalized oxygen consumption rate and total antioxidant capacity) were applied to assess metabolic and transcript divergences between C. gigas and C. angulata. Integrated analyses of metabolites and transcriptomes showed that C. gigas allocated more energy to storage and defense by suppressing glycolysis, fatty acid oxidation and by upregulating fatty acid synthesis, antioxidant gene expression, and related metabolites. The metabolic and transcript results were further confirmed by the phenotypic data that C. gigas has higher glycogen and crude fat content and fatty acid unsaturation and stronger antioxidant capacity than C. angulata. In contrast, C. angulata exhibited better growth performance and a higher oxygen consumption rate. These findings suggest that C. angulata allocates more energy to growth, which is embodied in its stronger aerobic capacity and higher levels of protein synthesis genes, metabolites, and growth-related biomarkers. This study will help to enlighten the evolutionary patterns and genetic basis of growth-defense trade-offs in marine ectotherms and the biochemical and molecular mechanisms underlying energy allocation. Also, the key genes and metabolites of glycogen and fatty acids pathway identified in this study will be applied for meat quality improvement in the oyster industry.

Background Fresh shrimp (Penaeus vannamei) deteriorates easily and the drying process is an important processing method for prolonging the shelf life of shrimp. The traditional drying method is hot-air-drying (HD), which can cause some problems such as nutrient loss, discoloration and lipid oxidation. In recent years, freeze-drying (FD) has been popular for removing moisture from food at lower temperatures, maintaining the structure of raw materials, and improving storage stability of products. In the present study, the effects of HD and FD on lipid and color of P. vannamei and the mechanisms involved were investigated. Results FD caused less lipid oxidation compared to HD; consequently, FD-processed shrimps had lower levels of primary and secondary oxidation products, as well as acid value, and higher contents of triacylglycerol, phosphatidylcholine, phosphatidylethanolamine, eicosapentaenoic acid and docosahexaenoic acid compared to HD-processed samples. Lipase and lipoxygenase played a role in the oxidation and hydrolysis of lipids during drying process. FD-processed shrimps had lower yellowness value and chromatic aberrations but a higher whiteness value compared to HD-processed samples. Correlation analysis showed that lipid oxidation, astaxanthin degradation and the Maillard reaction contributed to the changes of color. Principal component analysis indicated that FD caused less deterioration in quality compared to HD. Conclusion In the present study, FD is recommended for preserving shrimp color and lipid nutrition in terms of lipid oxidation control. © 2020 Society of Chemical Industry.

Compared with the ripeness of olefin metathesis, exploration of the construction of carbon-carbon double bonds through the catalytic carbonyl-olefin metathesis reaction remains stagnant and has received scant attention. Herein, a highly efficient AuCl3 -catalyzed intramolecular ring-closing carbonyl-olefin metathesis reaction is described. This method features easily accessible starting materials, simple operation, good functional-group tolerance and short reaction times, and provides the target cyclopentenes, polycycles, benzocarbocycles, and N-heterocycle derivatives in good to excellent yields.

Herein we report a pair of redox-responsive manganese complexes Mn(iii)/(ii)-N,N'-bis(2-hydroxy-4-trifluoromethylbenzyl)ethylenediamine-N,N'-diacetate (HTFBED, L1), which are water soluble and biologically interconvertible, as reversible redox-responsive probes in 1H/19F MRI for detecting and imaging biological redox species, offering a means to access valuable redox information associated with various diseases.

The last two decades have witnessed a rising interest in modulating the physicochemical properties of active pharmaceutical ingredients (APIs) through cocrystallization. The present study reports a new cocrystal of antimicrobial drug metronidazole (MNZ) using pyrogallol (PYR) as a cocrystal former, namely the MNZ–PYR cocrystal. The crystal structure of the MNZ–PYR cocrystal is studied by means of single-crystal X-ray diffraction, infrared spectroscopy, thermal analysis, and density functional theory calculations. The MNZ–PYR cocrystal shows an increased dissolution rate compared to MNZ due to the high energy conformer of PYR in the crystal lattice of the cocrystal. The formation of the MNZ–PYR cocrystal leads to a color shift from white (raw MNZ and PYR) to yellow, which is characterized by UV-vis spectroscopy and interpreted theoretically by means of time-dependent density functional theory calculations. The results suggest that the cocrystal strategy may be used for color tuning of APIs, offering opportunities for formulation development.

Molecular probes featuring promising capabilities including specific targeting, high signal-to-noise ratio, and in situ visualization of deep tissues are in great demand for tumor diagnosis and therapy. 19F magnetic resonance imaging (MRI) techniques incorporating stimuli-responsive probes are anticipated to be highly beneficial for specific detection and imaging of tumors because of negligible background and deep tissue penetration. Herein, we report a cascaded multiresponsive self-assembled nanoprobe, which enables sequential redox-triggered and near-infrared (NIR) irradiation-induced 19F MR signal activation/amplification for sensing and imaging. Specifically, we designed and synthesized a cascaded multiresponsive 19F-bearing nanoprobe based on the self-assembly of amphiphilic redox-responsive 19F-containing polymers and NIR-absorbing indocyanine green (ICG) molecules. It could realize the activation of 19F signals in the reducing tumor microenvironment and subsequent signal amplification via the photothermal process. This stepwise two-stage activation/amplification of 19F signals was validated by 19F NMR and MRI both in vitro and in vivo. The multiresponsive 19F nanoprobes capable of cascaded 19F signal activation/amplification and photothermal effect exertion can provide accurate sensing and imaging of tumors.

Pharmaceutical cocrystal as an alternative modification strategy presents opportunities for the formulation development of drugs with undesirable pharmacokinetic properties. Metronidazole (MNZ) is a water-soluble antimicrobial drug that can cause high plasma concentration peaks after administration, which may relate to serious encephalopathy. In the present study, the properties of MNZ were optimized through a cocrystallization strategy. A cocrystal of MNZ is prepared using gallic acid (GA) as cocrystal former. The structure of the prepared MNZ–GA cocrystal is studied by means of molecular dynamics and density functional theory calculations, powder X-ray diffraction, infrared spectroscopy, and thermal analysis. Comparative studies on the dissolution and absorption behaviors of raw MNZ and MNZ–GA cocrystal are completed. The results show that the MNZ–GA cocrystal exhibits lower Cmax and longer Tmax than pure metronidazole, suggesting that the prepared MNZ–GA cocrystal may find application in the formulation of MNZ.

Two diiron butane-1,2-dithiolate complexes containing tris(4-chlorophenyl)phosphine or tris(4-methoxyphenyl)phosphine have been prepared and characterized. Treatment of complex [Fe2(CO)6{μ-SCH2CH(C...

Researches establish an indispensable role of mitochondrial dysfunction in septic cardiomyopathy. We aimed to investigate the effects of long noncoding RNA (LncRNA) SOX2 overlapping transcript (SOX2OT) on mitochondrial dysfunction in septic cardiomyopathy. We observed an obvious overexpression of SOX2OT in septic hearts and cardiomyocytes. Knockdown of SOX2OT in mice recovered the reduced cardiac function, and improved the mitochondrial membrane potential impaired by lipopolysaccharide (LPS). SOX2OT overexpressed mice showed the opposite situation. In parallel, knockdown of SOX2OT in cardiomyocytes restored the mitochondrial membrane potential, along with reduced mitochondrial reactive oxygen species production induced by LPS, while overexpression of SOX2OT reversed these effects. Mechanistically, SOX2OT could regulate mitochondrial dysfunction in septic cardiomyopathy via SOX2. In general, SOX2OT contributed to mitochondrial dysfunction progression via inhibiting SOX2 expression in septic cardiomyopathy, which may provide a new insight for treatment of septic cardiomyopathy.

The design and synthesis of uranium sorbent materials with high uptake efficiency, capacity and selectivity, as well as excellent hydrolytic stability and radiation resistance remains a challenge. Herein, a polyoxometalate (POM)-organic framework material (SCU-19) with a rare inclined polycatenation structure was designed, synthesized through a solvothermal method, and tested for uranium separation. Under dark conditions, SCU-19 can efficiently capture uranium through ligand complexation using its exposed oxo atoms and partial chemical reduction from UVI to UIV by the low-valent Mo atoms in the POM. An additional UVI photocatalytic reduction mechanism can occur under visible light irradiation, leading to a higher uranium removal without saturation and faster sorption kinetics. SCU-19 is the only uranium sorbent material with three distinct sorption mechanisms, as further demonstrated by X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge structure (XANES) analysis.

Objective This study aimed to investigate changes in the ultrastructure, apoptosis, cycle progression, and migration ability of human MDA‐MB‐231 breast cancer cells under simulated microgravity conditions. Methods MDA‐MB‐231 breast cancer cells were cultured in a rotary cell culture system bioreactor to simulate microgravity for 7 days. The cells were randomly divided into a simulated microgravity (SMG) group and normal gravity control (NG) group. Changes in apoptosis, ultrastructure, cell cycle, and migration ability were evaluated. Results Transmission electron microscopy showed that cells in the SMG group had more secondary lysosomes than the NG groups. The flow cytometry assay showed that the proportion of apoptotic cells in the SMG group was significantly increased compared with the NG group; additionally, the median and interquartile spacing of the proportion of cells in the G0/G1 phase in the SMG group was lower than in the NG group, but the proportion of cells in the S phase was increased in the SMG group compared with the NG group. The transwell migration assay showed that cell migration in the SMG group was significantly reduced compared with the NG group. The expression of BCL‐2 and MMP9 in the SMG group was decreased compared with the NG group, whereas the expression of cyclin D3 in the SMG group was increased. Conclusion Simulated microgravity through rotary cell culture system had significant effects on human MDA‐MB‐231 breast cancer cells: the cell cycle and ultrastructure were impaired, apoptosis increased, migration ability decreased, and the expression of BCL‐2, cyclin D3, and MMP9 were affected.