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Graphical abstract Highlights • Trp-containing walnut peptides inhibited xanthine oxidase. • Peptide enhanced xanthine oxidase inhibition with increasing number of Trp residues. • Molecular docking of XO with 20 amino acids, 400 dipeptides and 8000 tripeptides. • Trp-containing peptides had high antioxidant activity. Abstract The modulation of xanthine oxidase (XO) activity is critical to the treatment of hyperuricemia and oxidative stress-related disease. Although the walnut protein hydrolysates had been reported to inhibit XO, their interaction mechanism remained unclear. Herein, the walnut protein-derived peptides were used to evaluate their in vitro XO-inhibitory activity and their inhibitory mechanism. The results suggested that Trp-containing walnut protein-derived peptides were able to effectively inhibit XO, moreover, the increased number of Trp would significantly enhance the XO-inhibitory activity of Trp-containing peptides. Similar to the allopurinol, Trp had active interaction with the critical residues Glu802, Leu873, Ser876, Arg880, Phe914, Phe1009, Thr1010, Val1011, Leu1014, Ala1078, Ala1079 and molybdopterin MOS3004 of XO, making Trp-containing peptide have high XOI activity. Simultaneously, the Trp-containing walnut protein-derived peptide also had been found to show great potential in antioxidant activity. Present work would introduce functional food-derived peptides for the improvement of hyperuricemia and oxidative stress-related disease. [ABSTRACT FROM AUTHOR]

In this work, we first successfully designed and fabricated the ternary plasmonic Ag/β-Ag 2 WO 4 /WO 3 photocatalysts with different contents of Ag/β-Ag 2 WO 4 particles in situ decorated on the surface of WO 3 nanoplates by a simple precipitation method at room temperature condition. The photocatalytic activity of as-prepared samples was investigated by degradation of rhodamine B (RhB), methylene blue (MB) and methyl orange (MO) under visible-light irradiation. It was found that the prepared 40 wt% Ag/β-Ag 2 WO 4 /WO 3 photocatalyst showed the highest photocatalytic RhB efficiency with 83.21 and 86.83 times higher than those of pure WO 3 and Ag/β-Ag 2 WO 4 samples, respectively. The highly enhanced photocatalytic performance was attributed to the Z-scheme mechanism in this ternary composites, in which Ag particles play a crucial role by the surface plasmon resonance (SPR) effect; meanwhile, Ag particles also can work as the charge transmission-bridge, giving rise to effectively restraining recombination of the photogenerated charge carriers. This novel ternary Ag/β-Ag 2 WO 4 /WO 3 nanostructures may provide an appropriate insight in the consideration as an ideal candidate in environmental remediation. [ABSTRACT FROM AUTHOR]

• A novel parallel one-class classifiers method is proposed for incremental learning based on variational auto-encoder (VAE). • A classifier-contrastive loss and an inter-class loss are introduced to enhance the comparability between VAEs. • A hinge reconstruction loss is proposed to improve the modeling robustness of each VAE and ensure its discriminability. • Extensive experiments show the effectiveness and robustness of the proposed method. The exemplar-free class incremental learning (IL) requires classification models to learn new-class knowledge incrementally without retaining any old samples. Recently, the IL framework based on parallel one-class classifiers (POC) has demonstrated promising performance. It trains a one-class classifier (OCC) for each category and thus is immune to the catastrophic forgetting problem. However, the single-class training strategy may incur weak discriminability and low comparability between different classifiers in POC. To meet this challenge, we propose a new IL framework, referred to as D iscriminative and C omparable P arallel O ne-class C lassifiers (DCPOC). Instead of ordinary OCCs (e.g., deep SVDD) used in other POC methods, DCPOC adopts variational auto-encoders (VAE) as OCCs because VAEs can be used not only to identify classes for given samples but also to generate pseudo samples for the trained classes. With this advantage, DCPOC trains a new-class VAE in contrast with the old-class VAEs, which benefits the new-class VAE to reconstruct better for new-class samples but worse for old-class pseudo samples, thus enhancing the comparability. Furthermore, DCPOC introduces a hinge reconstruction loss to reinforce the discriminability. We evaluate our method on MNIST, CIFAR10, CIFAR100, Tiny-ImageNet, and ImageNet. The experimental results show that DCPOC achieves state-of-the-art performance on these datasets. 1 1 The source code is publicly available at https://github.com/SunWenJu123/DCPOC [ABSTRACT FROM AUTHOR]

In the present work the photocatalytic activity of CdS(x)/Ag/g-C 3 N 4 (x = 10, 20, 40, 60 wt% of the CdS) hybrid heterostructured photocatalyst was investigated. Prior the depositions of CdS over the surface of g-C 3 N 4 , an optimal concentration of Ag nanoparticles as electron conducting bridge were deposited between the interfaces of CdS and g-C 3 N 4 nanosheets. Being as a plasmon metal, the Ag nanoparticles were deposited to increase the absorption of visible light via surface plasmon resonance effect. The deposition of Ag between the interfaces of CdS nanospeheres and g-C 3 N 4 can greatly facilitate the migration of electron and reduce the electron-hole recombination during the photocatalytic degradation of organic pollutants. The hybrid heterostructure shows significant photocatalytic activity and photostability compare with pure g-C 3 N 4 , CdS and CdS/g-C 3 N 4 samples. It is concluded that the hybrid heterostructure provide significant photocatalytic degradation activity through an efficient and facilitated electron transfer mechanism. [ABSTRACT FROM AUTHOR]

The understanding of the interactions between starch and cellulose hydrocolloids is crucial for equipment design and definition of operation parameters in the food industry. In the present study, the possible interactions of wheat starch (WS) with different levels (2–10%) of carboxymethyl cellulose (CMC) or microcrystalline cellulose (MCC) in short-term retrogradation were explored by dynamic rheological and Fourier transform infrared spectrum (FTIR) measurements. The chains of water-soluble CMC could creep into the continuous phase during paste gelation. It was found the amylose network structure was broken and the inter- and intra-molecular hydrogen bond of WS were weaken after gelation. Moreover, there were interactions between the chains of CMC and chains of amylose at higher CMC concentration. On other hand, water connected with COO − groups blocked the interactions between CMC chains and amylose, and the interactions among CMC chains. The amorphous phases of high crystalline MCC were just swollen during paste gelation. It results that heterogeneous microstructure with amylose and MCC domains unevenly distributed was in WS/MCC paste. [ABSTRACT FROM AUTHOR]

In this paper, we chose diffident kinds of ionic liquids to optimal selection an optimal one to extract alkaloids from Phellodendron amurense Rupr . Four ionic liquids with diffident carbon chains or anions have been investigated and 1-butyl-3-methylimidazolium bromide with best productivity. Then, selections have been optimized in different conditions, including concentration of ionic liquid, time for ultrasonic treatment, ultrasonic power and solid–liquid ratio. Moreover, three conditions have been comprehensively assessment by response surface methodology, the optimal conditions were determined as follows ultrasonic power 100 W, extraction time 75 min and ratio of solvent to raw material 1:14. Under these conditions, the yield% (MIX) was 106.7% (extracted by heat reflux being defined 100%). Comparing with other methods, the advantages are saving conserving, time saving, high yield% and especially pollution-free. [ABSTRACT FROM AUTHOR]

In this study, 12 asymmetric curcumin (CUR) analogues and 5 symmetric curcumin derivatives were synthesized, the antioxidant activity of these derivatives were evaluated by radicals 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay, 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) assay, ROO (TRAP) assay and O 2− (NET) assay and anti-proliferative activities of these analogues were assessed against the human hepatoma cell line (SMMC-7721), the human breast cancer cell line (MCF-7) and the human prostate cancer cell lines (PC-3). Most of the asymmetric compounds showed stronger antioxidant activities than Vitamin C (Vc). Curcumin analogues reducing free radicals contain two reaction mechanisms: H-atom and electron transfer mechanisms. Compound 14 showed the most significant antioxidant activity compared with curcumin and other derivatives. Shorted the carbon chain of 14 can reduce the O–H bond dissociation enthalpy (BED) to improve the antioxidant activity. The antioxidant activity of 25 was similar to curcumin. All of the compounds performed better in an anti-proliferate assay than curcumin, especially compound 25 , which exhibited the preferential cytotoxic activity against MCF-7 cells( 25 , IC 50 = 9.11 μM, curcumin, IC 50 = 70.2 μM). Considering these data, future studies should be performed to assess the therapeutic values of these asymmetric curcumin analogues. [ABSTRACT FROM AUTHOR]

A novel conjugate of camptothecin and artesunate (C–Q) was prepared and its cytotoxicity was evaluated using the MTT assay. In addition, the antitumour activity and toxicity of C–Q were investigated in mice, and interaction between transferrin (TF) and C–Q was investigated to evaluate its interaction with biological macromolecules. In the MTT assay, C–Q showed better inhibitory activity against MCF7 breast cancer cells and SMMC-7721 liver cancer cells than camptothecin or artesunate. In vivo, C–Q showed lower toxicity and better antitumour activity compared with camptothecin. Fluorescence spectroscopy showed static quenching of TF in the presence of C–Q, and thermodynamic parameters (Δ H > 0 and Δ G < 0) indicated that the reaction was spontaneous and endothermic. The main binding force between C–Q and TF was hydrophobic, as indicated by thermodynamic parameters (Δ H > 0 and Δ S > 0). Thus, synchronous fluorescence spectra showed that C–Q had no influence on the conformation of TF. Our results indicated that C–Q represents a novel potential anticancer therapeutic vector with advantages over current methods of CPT and ART administration. This novel drug delivery system allows the use of these drugs in a manner associated with few side effects for normal tissue, and which facilitates synergistic effects of anti-tumour drugs. [ABSTRACT FROM AUTHOR]

• A novel Cluster-Prototype Matching (CPM) strategy is proposed to solve the domain shift problem of zero-shot learning. • The distribution information of samples in the embedding space, i.e., cluster structure, is utilized to assist in zero-shot learning classification. • The CPM strategy can be applied to most existing ZSL models in a plug-and-play style. • Extensive experiments show the effectiveness and robustness of the proposed method. Given the descriptions of classes, Zero-Shot Learning (ZSL) aims to recognize unseen samples by learning a projection between the visual features of samples and the semantic descriptions (prototypes) of classes from seen data. However, due to the inherent distribution gap between seen and unseen domains, the learned projection is generally biased to seen classes and may produce misleading relationships between unseen samples and prototypes (sample-prototype relationship). To tackle this problem, we propose a Cluster-Prototype Matching (CPM) framework which exploits the distribution information of samples to explore the cluster structure of samples and then use the robust cluster-prototype relationship to correct the biased sample-prototype relationship. Specifically, we first use an iterative cluster generation module to identify the underlying cluster structure of samples based on their embedding features, which are acquired via a basic ZSL model. Then each identified cluster will be matched with a specific class prototype through the Kuhn-Munkres algorithm, based on which we can export a sharp cluster-prototype similarity. Finally, the cluster-prototype similarity is combined with the sample-prototype similarity to determine the class labels of test samples. We apply CPM to five well-established ZSL methods and the experimental results show that CPM can significantly improve the performance of basic models and enable them achieve or beyond the state-of-the-art. [ABSTRACT FROM AUTHOR]

In this present study, a series of CuO doped red mud (CuO/URM) particle electrodes with different CuO doping contents were prepared by physical impregnation method with ultrasonic assistance, and applied in a three-dimensional electro-Fenton (3D/EF) system for ciprofloxacin degradation. The synthesized CuO/URM particle electrodes were characterized by SEM, EDS, TEM, HRTEM, XRD, BET, XPS and EIS. It was found that the prepared CuO/URM particle electrode has excellent mesopore structure and high specific surface area, and the CuO doping could effectively reduce the resistance of particle electrode and accelerate the electron transfer. The results of comparison experiment, capture of active species experiment, ESR analysis and XPS analysis showed that the high electrocatalytic activity of the 3D/EF system was due to the combined effects of adsorption by particle electrode, direct oxidation from both anode and CuO/URM particle electrode, and indirect oxidation by active species generated in the system, and the possible catalytic mechanisms in the 3D/EF system catalyzed by 0.1CuO/URM was proposed. All results demonstrated that the 3D/EF system catalyzed by CuO/URM particle electrodes is a reliable technology for the disposal of CIP wastewater. [Display omitted] • CuO doped red mud particle electrode for 3D/electro-Fenton (3D/EF) has been prepared. • Ciprofloxacin degradation is effective by the 3D/EF system. • Catalytic mechanism of 3D/EF system catalyzed by the particle electrode is proposed. • Reason for the high oxidative ability of 3D/EF system has been discussed. [ABSTRACT FROM AUTHOR]

Abstract: A liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was developed to identify and quantify the camptothecin quaternary derivative CPT8 for application in pharmacokinetics and tissue distribution studies. Rat plasma and tissue samples were extracted with methanol by using camptothecin as the internal standard (IS). Chromatographic separation of CPT8 and the IS was achieved using a Hypersil GOLD C18 column, with a flow rate of 1.0mL/min followed by quantification with tandem mass spectrometry, operating with electrospray ionization in the positive ion mode and by applying multiple reaction monitoring. The MS/MS ion transitions were monitored at m/z 484.3–361.2 for CPT8 and m/z 349.0–305.2 for the IS (CPT). A calibration curve was constructed using CPT8 concentrations ranging from 2.5ng/mL to 2500ng/mL (r>0.993). The efficiency of CPT8 extraction from plasma and tissue samples ranged from 91.23% to 105.4%. Intra- and inter-day precision (relative standard deviation) values were 0.21% and 7.25%, respectively. No matrix effects were observed. The freeze–thaw stability, post-extraction stability, and stability following short- and long-term storage at low temperatures ranged from 84.12% to 108.2%. The preclinical data obtained using this method is expected to facilitate future clinical investigations of CPT8. [ABSTRACT FROM AUTHOR]

Abstract: More and more digitized art images are accumulated and expanded in our daily life and techniques are needed to be established on how to organize and retrieve them. Though content-based image retrieval (CBIR) made great progress, current low-level visual information based retrieval technology in CBIR does not allow users to search images by high-level semantics for art image retrieval. We propose a fuzzy approach to describe and to extract the fuzzy aesthetic semantic feature of art images. Aiming to deal with the subjectivity and vagueness of human aesthetic perception, we utilize the linguistic variable to describe the image aesthetic semantics, so it becomes possible to depict images in linguistic expression such as ‘very action’. Furthermore, we apply neural network approach to model the process of human aesthetic perception and to extract the fuzzy aesthetic semantic feature vector. The art image retrieval system based on fuzzy aesthetic semantic feature makes users more naturally search desired images by linguistic expression. We report extensive empirical studies based on a 5000-image set, and experimental results demonstrate that the proposed approach achieves excellent performance in terms of retrieval accuracy. [Copyright &y& Elsevier]

Abstract: In an attempt to improve the antitumor activity and decrease the cytotoxicity of camptothecin, 18 new 10-substituted camptothecin derivatives were prepared. The cytotoxicity in vitro on cancer cell lines and antitumor activity in vivo, and inhibitory properties of topoisomerase I of these derivatives were evaluated. Most of these derivatives possessed lower cytotoxicities than CPT, and the compounds 13, 21, 22, 23, and 24 showed similar topoisomerase I inhibitory activity to CPT. Analogues 13 exhibited the best antitumor activity in vivo among all derivatives we prepared. [Copyright &y& Elsevier]

Abstract: In an effort to decrease the toxicity and improve the stability of labile lactone ring of camptothecin, nitrogenous heterocyclic aromatic groups were introduced into 20-position of camptothecin and seventeen new 20s-camptothecin derivatives were obtained in quantitative yield. The cytotoxicity in vitro on three cancer cell lines and the stability of the lactone in phosphate-buffered solution (PBS) of these derivatives were evaluated. Most of these tested derivatives possessed better cytotoxicity than topotecan. Analogues 6, 12 exhibited the best antitumor activity in vivo in all derivatives we prepared. The results suggested that introduction of pyrazole in 10- or 20-position of camptothecin could promote antitumor activity in vitro and in vivo, simultaneously bring much increase of the stability of lactone. [Copyright &y& Elsevier]

Highlights • Bonito hydrolysates exhibited excellent anti-hyperuricemic activity and renal protection function. • Hexapeptide PGACSN and tripeptide WML displayed inhibitory effects on xanthine oxidase. • Hydrophobic amino acids play an important role in the xanthine oxidase inhibitory activity of WML. Abstract Traditional drugs used to treat hyperuricemia have adverse effects. In this study, to identify safer anti-hyperuricemic bioactive peptides isolated from food-derived protein hydrolysates, a hyperuricemia rat model induced by potassium oxonate (PO) was used to evaluate the activity of bonito hydrolysates (BH), dephenolised walnut hydrolysates (DWH), and soybean hydrolysates (SH). The serum uric acid level of rats in the BH group (95.4 ± 27.4 μM, p < 0.01) was significantly reduced compared to that in the model group (212.00 ± 30.00 μM) to a level even lower than that in allopurinol group (114.3 ± 53.0 μM). Furthermore, BH alleviated renal impairment caused by PO in vivo and exhibited the greatest xanthine oxidase (XOD) inhibitory activity (65.5 ± 8.0%) in vitro compared to the other hydrolysates. Two peptides identified from BH bound the catalytic site of XOD, among which the hydrophobic peptide WML entered the active site of XOD more easily compared to the hydrophilic peptide PGACSN, possibly because of hydrophobic interactions. The chemically synthesized WML demonstrated high XOD inhibitory effect compared to PGACSN and a significant change in the secondary structure of XOD. Therefore, hexapeptide PGACSN and tripeptide WML are partially responsible for the anti-hyperuricemic activity of BH, and hydrophobic amino acids play important roles in the XOD inhibitory activity of peptides. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to evaluate the in vitro and in vivo antitumor efficacy and the dose dependent toxicity of camptothecin nanosuspension (Nano-CPT) comparing with that of topotecan (TPT). A novel supercritical antisolvent (SAS) process-high pressure homogenization technique has been developed to prepare Nano-CPT. The cytotoxicity of Nano-CPT and TPT was investigated against MCF-7, HCT-8, and PC-3 cell lines using MTT assay, antitumor activity in vivo were evaluated against HCT-8 xenograft model, and the dose dependent toxicity in vivo during the treatment were investigated by body weight changes and relative organ weight variations. The Nano-CPT presents about 6 times in vitro cytotoxicity active than TPT against cell lines MCF-7, nearly the same in vivo antitumor activity with TPT and lower toxicity. The results confirm that Nano-CPT is a novel potential formulation with high antitumor efficacy and low toxicity. [Copyright &y& Elsevier]

Beta-amyloid (Aβ) has pivotal functions in the pathogenesis of Alzheimer's Disease (AD). In the present study, we adopted an vitro model that involved Aβ 25-35 -induced oxidative damage in PC12 cells. Aβ 25-35 (10 μΜ) treatment for 24 h induced significant cell death and oxidative stress in PC12 cells, as evidenced by cell viability reduction, LDH release, ROS accumulation and increased production MDA. (1E,4E)-1, 5-bis(4-hydroxy-3-methoxyphenyl) penta-1, 4-dien-3-one (CB) and (1E, 4E)-1-(3, 4-dimethoxyphenyl)-5-(4-hydroxy-3, 5-dime-thoxyphenyl) Penta-1, 4-dien-3-one (FE), two Curcumin (Cur) analogues displayed neuroprotective effects against Aβ 25-35 -induced oxidative damage and cellular apoptosis in PC12 cells. Here, we investigated three different treatment ways of CB and FE. It was interesting that post-treatment of CB and FE (restoring way) showed similar effect to the preventive way, while attenuating way did not show any protective effect. We found that low dose CB and FE increased transcriptional factor NF-E2-related factor 2 (Nrf2)/hemo oxygenase 1 (HO-1) protein expression and decreased Kelch-like ECH-associated protein 1 (Keap1) in PC 12 cells. In addition, CB and FE promoted the translation of Nrf2 into nuclear and enhanced the activity of superoxide dismutase (SOD)/catalase, which confirmed cytoprotection against Aβ 25-35 -induced oxidative damage. Moreover, CB and FE could increase Bcl-2 expression level, decrease the level of Bax and Cyt-c in Aβ 25-35 -treated PC12 cells. Ultimately, the neuroprotective effect of CB and FE provides a pharmacological basis for its clinical use in prevention and treatment of AD. • Mono-carbonyl analogues of curcumin, CB and FE, exhibited equivalent cytotoxicity in very low dosage compared to Cur. • Low dose CB and FE played neuroprotection against Aβ 25-35 -induced oxidative stress. • CB and FE functioned through both antioxidant and anti-apoptosis pathways. [ABSTRACT FROM AUTHOR]

The co-administration of anticancer drugs and P-glycoprotein (P-gp) inhibitors was a treatment strategy to surmount multidrug resistance (MDR) in anticancer chemotherapy. In this study, novel phenylfuran-bisamide derivatives were designed as P-gp inhibitors based on target-based drug design, and 31 novel compounds were synthesized and screened on MCF-7/ADR cells. The result of bioassay revealed that compound y12d exhibited low cytotoxicity and promising MDR reversal activity (IC 50 = 0.0320 μM, reversal fold = 1163.0), 3.64-fold better than third-generation P-gp inhibitor tariquidar (IC 50 = 0.1165 μM, reversal fold = 319.3). The results of Western blot and rhodamine 123 accumulation verified that compound y12d exhibited excellent MDR reversal activity by inhibiting the efflux function of P-gp but not expression. Furthermore, molecular docking showed that compound y12d bound to target P-gp by forming the double H-bond interactions with residue Gln 725. These results suggest that compound y12d might be a potential MDR reveal agent acting as a P-gp inhibitor in clinical therapeutics, and provide insight into design strategy and skeleton optimization for the development of P-gp inhibitors. [Display omitted] • A series of novel P-gp inhibitor are obtained by combining target-based drug design with empirical modifications. • Compound y12d exhibits low cytotoxicity and promising MDR reversal activity, better than third-generation P-gp inhibitor tariquidar. • The action mechanism of compound y12d relies on inhibiting the efflux function of P-gp. • These results provide insight into design strategy and skeleton optimization for the development of P-gp inhibitors. [ABSTRACT FROM AUTHOR]

The goal of this work is to develop the method of preparing folate (FA)-decorated human serum albumin (HSA) loaded with nano-hydroxycamptothecin (nHCPT) nanoparticles (NPs) (FA-HSA-nHCPT-NPs) and to explore its antitumor activity in vivo and in vitro . FA-HSA-nHCPT-NPs were obtained by preparing nHCPT by a high-pressure homogenization technique followed with an anti-solvent method. The drug-loading efficiency of the FA-HSA-nHCPT-NPs was 7.8%. We adopted the human breast cancer cells (FA receptor-expressing MCF-7 cells) and BALB/c mice inoculated with human MCF-7 cells to determine the antitumor activity of FA-HSA-nHCPT-NPs in vitro and in vivo , respectively. The antitumor activity of FA-HSA-nHCPT-NPs was stronger than that of the raw HCPT in both conditions. Tissue distribution analysis showed that the FA-HSA-nHCPT-NPs carried more HCPT to tumors than the raw HCPT. The tumor inhibitory rate of FA-HSA-nHCPT-NPs was much higher compared with the raw HCPT. Th7us, the FA-HSA-nHCPT-NPs could serve as a viable delivery system with an obvious target effect on tumor. [ABSTRACT FROM AUTHOR]

In this paper, response surface methodology was employed to optimize experimental process for ionic liquid based ultrasonic assisted extraction of curcuminoids compounds from rhizomes of Curcuma longa L. The Box–Behnken design on three factors and five levels together with response surface methodology were used to optimize experimental conditions for total curcuminoids content and radical scavenging capacity. The radical scavenging capacity was determined by ABTS and TRAP methods. For the ionic liquid based ultrasonic assisted extraction, optimum process was set as below: [Omim]Br concentration, 4.2 mol/L; liquid-raw ratio, 30 mL/g; extraction time, 90 min; ultrasonic power, 250 W. [ABSTRACT FROM AUTHOR]