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Sensors used to detect explosive, flammable, toxic, and harmful gases are in focus of research. The gas sensor can be affected by many factors in the process of use, and among the many adverse elements affecting the function of the gas sensor, humidity is the most common. With the rapid development of gas sensors, the influence of humidity on gas sensors has been paid more and more attention. To reduce the impact of humidity, many methods have been proposed. In this review, the specific impact of humidity on the function of metal‐oxide semiconductors and solid electrolyte gas sensors is summarized. Practical techniques are proposed to reduce the effect of humidity on device performance, which is of great help in improving the detection efficiency and quality of gas sensors in high‐humidity environment. The information may be valuable for expanding the application field of gas sensors. [ABSTRACT FROM AUTHOR]

Polyamide elastomer (PAE) is a novel material which may improve the performances of acrylonitrile‐butadiene rubber (NBR). This work uses equilibrium swelling and rheological apparatus to study the effects of the PAE content on the overall crosslink densities of NBR/PAE vulcanizate. The presence of PAE significantly increased the overall crosslink density. During the aging stage, the overall crosslink density first increased and then decreased with increasing aging temperature from 25 to 150°C. There was a linear relationship between the tensile strength with the overall crosslink density of the NBR/PAE vulcanizate. Oil resistance of the NBR/PAE vulcanizate was improved with increasing PAE content. [ABSTRACT FROM AUTHOR]

The study on swelling behaviors of rubber products in liquid media is of great value for life prediction and practical application guidance. In this work, changes in the mechanical properties of hydrogenated nitrile rubber/ethylene propylene diene monomer (HNBR/EPDM) blends caused by swelling in aviation hydraulic oil YH‐15 were studied. Effects of two kinds of carbon black, N220, and N990, on the tensile properties of HNBR/EPDM blends at both unswollen and swollen states were investigated. The results turned out that N220 exhibited better reinforcing effects than N990 on HNBR/EPDM blends. The tensile properties of unfilled and filled HNBR/EPDM blends decreased rapidly at first and then tended to stabilize with the extension of swelling time in YH‐15, while the modulus at 100% declined firstly and then increased. After swelling for 72 h, the tensile strength of HNBR/EPDM blends filled with N220 decreased by more than 35%, and by comparison, it decreased by about 20% for the N990‐filled HNBR/EPDM blends. The cross‐sections of the tensile samples after swelling changed greatly compared with the unswollen samples. In addition, the effect of swelling on the hardness of the HNBR/EPDM blends was not obvious. [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factor receptor 2 (VEGFR2)/KDR plays a critical role in tumor growth, diffusion, and invasion. The amino acid sequence homology of KDR between mouse and human in the VEGF ligand‐binding domain was low, thus the WT mice could not be used to evaluate Abs against human KDR, and the lack of a suitable mouse model hindered both basic research and drug developments. Using the CRISPR/Cas9 technique, we successfully inserted different fragments of the human KDR coding sequence into the chromosomal mouse Kdr exon 4 locus to obtain an hKDR humanized mouse that can be used to evaluate the marketed Ab ramucirumab. In addition, the humanized mAb VEGFR‐HK19 was developed, and a series of comparative assays with ramucirumab as the benchmark revealed that VEGFR‐HK19 has higher affinity and superior antiproliferation activity. Moreover, VEGFR‐HK19 selectively inhibited tumor growth in the hKDR mouse model but not in WT mice. The most important binding epitopes of VEGFR2‐HK19 are D257, L313, and T315, located in the VEGF binding region. Therefore, the VEGFR2‐HK19 Ab inhibits tumor growth by blocking VEGF‐induced angiogenesis, inflammation, and promoting apoptosis. To our best knowledge, this novel humanized KDR mouse fills the gaps both in an animal model and the suitable in vivo evaluation method for developing antiangiogenesis therapies in the future, and the newly established humanized Ab is expected to be a drug candidate possibly benefitting tumor patients. [ABSTRACT FROM AUTHOR]

Background: Dishevelled (DVL) family members are crucial to Wnt‐induced signaling transduction, and their expression is highly correlated with the progression of multiple malignant cancers. However, the expression profiles and exact prognostic values of DVLs in hepatocellular carcinoma (HCC) have not been explored until now. Methods: The expression of DVL isoforms was assessed using the Oncomine, HCCDB and UALCAN databases. The prognostic roles of DVLs were further evaluated using the GEPIA database. The relationship between the expression of DVLs and immune infiltration of HCC was investigated using the Timer and ImmuCellAI tools. Furthermore, protein–protein interaction (PPI) networks were built and enrichment analyses were conducted. Results: We found that the expression levels of DVL2 (OMIM accession number: 602151) and DVL3 (OMIM accession number: 601368) were upregulated in HCC tissues as revealed by the Oncomine and HCCDB databases. Additionally, the expression of DVLs tended to be associated with advanced clinical features in the UALCAN database. Prognostic analysis revealed that the expression levels of DVL1 (OMIM accession number: 601365) and DVL3 were remarkably associated with a poor prognosis in HCC patients. The results also revealed that the DVL expression level was correlated with the infiltration levels of multiple immune cells. By constructing the PPI network and enrichment analyses, the DVL1‐3 gene was identified to interact with 20 key genes and participate in several pathways. Conclusion: In summary, DVL2 and DVL3 are highly expressed in HCC, and DVL1 and DVL3 are related to a poor prognosis, which might be used as candidate targets for targeted therapy and reliable prognostic biomarkers in HCC. [ABSTRACT FROM AUTHOR]

Triple‐negative breast cancer (TNBC) is one of the most aggressive subtypes of breast cancer with negativity for oestrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor (HER2). Non‐coding RNAs (ncRNAs) make up most of the transcriptome and are widely present in eukaryotic cells. In recent years, emerging evidence suggests that ncRNAs, mainly microRNAs (miRNAs), long ncRNAs (lncRNAs) and circular RNAs (circRNAs), play prominent roles in the tumorigenesis and development of TNBC, but the functions of most ncRNAs have not been fully described. In this review, we systematically elucidate the general characteristics and biogenesis of miRNAs, lncRNAs and circRNAs, discuss the emerging functions of these ncRNAs in TNBC and present future perspectives in clinical practice. [ABSTRACT FROM AUTHOR]

Summary: To identify novel antioxidant peptides from egg‐white protein and investigate antioxidant mechanism, the hydrolysate of egg‐white protein was purified by ultrafiltration and a Sephadex G‐15 column. The peptides VYLPR, EVYLPR, VEVYLPR and VVEVYLPR were identified from the fraction with the highest antioxidant activity. The Results showed that the peptide VYLPR exhibited the strongest protective effect on HEK‐293 cells. The viability of cells recovered to 97.45 ± 1.98% with pre‐treatment of 20 μm VYLPR. We further investigated antioxidant mechanism. The results showed VYLPR could inhibit lipid peroxidation process, maintain cell membrane integrity, inhibit intracellular LDH activity, reduce MDA content, and improve the activity of antioxidant enzyme T‐SOD and GSH‐Px. This work could help researchers in understanding antioxidant mechanism of peptides and also contribute to developing functional egg‐white product. [ABSTRACT FROM AUTHOR]

Microwave- and ultrasound-assisted methods based on a quick, easy, cheap, effective, rugged, and safe sample preparation approach followed by high-performance liquid chromatography with tandem mass spectrometry were developed for the simultaneous determination of eight bisphenol analogues in serum and sediment. The developed methods provided satisfactory extraction efficiency for the energy provided by microwaves and ultrasound. Compositions of commercial sorbents (primary secondary amine, MgSO4, octadecyl-modified silica, and graphitized carbon black) were evaluated. The ultrasound-assisted method was suited for serum using primary secondary amine, MgSO4, and octadecyl-modified silica as sorbents and a mixture of hexane and ethyl acetate as extraction solvent. The microwave-assisted method worked better for sediment with tetrahydrofuran and methanol as solvents and primary secondary amine, MgSO4, octadecyl-modified silica, and graphitized carbon black as sorbents. Other experimental parameters, such as extraction temperature and time, were also optimized. The inter- and intraday relative standard deviations ranged from 2.7 to 5.5%. The limits of detection were between 0.1 and 1.0 ng/mL for serum and between 0.1 and 0.5 ng/g dry weight for sediment. The proposed methods were successfully applied to seven sediment and 20 human serum samples. The results showed that the developed methods were practical for the analysis and biomonitoring of bisphenols in sera and sediment. [ABSTRACT FROM AUTHOR]

NF90 is a novel host antiviral factor that regulates PKR activation and stress granule formation in influenza A virus ( IAV)-infected cells, but the precise mechanisms by which it operates remain unclear. We identified NF90 as a novel interacting protein of IAV nonstructural protein 1 ( NS1). The interaction was dependent on the RNA-binding properties of NS1. NS1 associated with NF90 and PKR simultaneously; however, the interaction between NF90 and PKR was restricted by NS1. Knockdown of NF90 promoted inhibition of PKR phosphorylation induced by NS1, while coexpression of NF90 impeded reduction of PKR phosphorylation and stress granule formation triggered by NS1. In summary, NF90 exerts its antiviral activity by antagonizing the inhibitory role of NS1 on PKR phosphorylation. [ABSTRACT FROM AUTHOR]

Phellinus igniarius has antibacterial, antiviral, antioxidative, antitumor, and antimutagenic effects. In this study, an integrative pattern recognition approach using principal component analysis and orthogonal partial least squares discriminant analysis was successfully applied for the rapid analysis of natural compounds in traditional Chinese medicine. An ultra high performance liquid chromatography with synapt high-definition mass spectrometry method and MassLynx software was used. This method employed gradient elution to rapidly analyze and characterize chemical constituents and metabolites after the oral administration of a P. igniarius ethanol extract. There were 24 peaks within 10 min of the analysis time and 20 of these were identified or tentatively characterized on the basis of their fragmentation behaviors. In the S-plot of the orthogonal partial least squares discriminant analysis, 27 ions were extracted to make the serum. Among them, nine absorbed the prototype components and 18 metabolites were identified in vivo. Glucuronidation, oxidation, and methylation were the major metabolic reactions. This study is the first systematic analysis and characterization of the chemical constituents and metabolites in an ethanol extract of P. igniarius. This method can be applied to the rapid analysis and characterization of constituents in rat serum after the oral administration of other compounds used in traditional Chinese medicines. [ABSTRACT FROM AUTHOR]

ABSTRACT The metabolism of swertiamarin (STM) in vivo was studied by LC/MS following picolinoyl derivatization. Incubation of erythrocentaurin (ECR), one of the main in vitro metabolites of STM by intestinal bacteria, with liver microsome indicated that STM may be metabolized to the final metabolite 3,4-dihydro-5-(hydroxymethyl) isochroman-1-one (HMIO) in vivo. After hydrolyzation with sulfatase, HMIO was successfully detected in rat plasma after oral administration of STM by LC/MS following picolinoyl derivatization. 4-Methoxyphenyl methanol was used as the internal standard to quantify HMIO in rat plasma. The full metabolic pathway of STM in rats is proposed. STM is first hydrolyzed by bacterial β-glucusidase to give aglycone, which is readily converted to ECR and nitrogen-containing metabolite. ECR is further reduced to HMIO by both liver and intestinal bacteria and HMIO is finally converted to the new sulfate conjugate metabolite. The monoterpene compound STM was found to be metabolized to dihydroisocoumarin and alkaloid compounds in vivo, which may be responsible for the pharmacological effect of STM. The results may shed light on clinical efficacy of STM and the new analytical method developed may assist in studies of the metabolism of other natural iridoids and secoiridoids in vivo. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The metabolism of gentiopicroside ( GPS) in vivo was studied for the first time by LC- MS following picolinoyl derivatization. Incubation of erythrocentaurin, one of the main in vitro metabolites of GPS by intestinal bacteria, with liver microsome indicated that GPS might be metabolized to a final metabolite 3,4-dihydro-5-(hydroxymethyl)isochroman-1-one ( HMIO) in vivo. After hydrolysis with sulfatase, HMIO was successfully detected in rat plasma after oral administration of GPS by LC-MS following picolinoyl derivatization. 4-Methoxyphenyl methanol was used as an internal standard to quantify HMIO in rat plasma. A metabolic pathway of GPS in rats is proposed. The monoterpene compound GPS was found to be metabolized to dihydroisocoumarin, which may be responsible for the pharmacological effect of GPS. [ABSTRACT FROM AUTHOR]

Zhibai dihuang pill is a famous traditional Chinese medicine formula containing the herbal medicine Phellodendri amurensis cortex. In this work, an integrative pattern recognition approach including principal component analysis and orthogonal partial least squared discriminant analysis based on ultra-performance liquid chromatography coupled to MS was successfully applied for the rapid discovery of natural compounds from herbal medicines. In a 24 min analysis, 93 compounds were identified or tentatively characterized from Zhibai dihuang pill based on their fragmentation behaviors, 23 of which were from Phellodendri amurensis cortex. A total of 26 metabolites in plasma were identified from Phellodendri amurensis cortex in Zhibai dihuang pill formula, among them, 12 prototypes and 14 metabolites through metabolic pathways of demethylation, methylation, hydrolysis, sulfate conjugation, and glucuronide conjugation, which were seven metabolites more than that of the single drug, suggesting the importance of the compatibility of traditional Chinese medicine. The present study provided important structural information on the metabolism of Zhibai dihuang pill. Furthermore, the results of this work have demonstrated the feasibility of ultra-performance liquid chromatography coupled to MS for the rapid and reliable characterization of metabolites from herbal medicines. Based on these results, this method could be a novel approach for identifying potentially bioactive components in other traditional Chinese medicines. [ABSTRACT FROM AUTHOR]