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In this paper, we demonstrated a distributed feedback fiber-laser- (DFB-FL) based ultrasound detection system with a high signal-to-noise ratio (SNR), high sensitivity and wide frequency response range. The DFB-FL was fabricated by UV-inscribing a π phase-shifted grating in the Erbium–Ytterbium co-doped fiber using the phase mask method. The theory of DFB-FL and the sensing principle has been discussed and analyzed. The sensing signal was demodulated via an unbalanced Mach–Zehnder interferometer (MZI) system. The experimental results showed that the sensitivity of the sensor reached 75.18 mV/kPa and the flat frequency response range covered over 30 MHz, which covered the ultrasonic detection frequency range of abnormal discharge in the electric power system. The SNR of this DFB-FL was 42.9 dB, and the corresponding noise-equivalent pressure was calculated as 0.12 kPa. [ABSTRACT FROM AUTHOR]

Glycosaminoglycans (GAGs) are valuable bioactive polysaccharides with promising biomedical and pharmaceutical applications. In this study, we analyzed GAGs using HPLC-MS/MS from the bone (B), muscle (M), skin (S), and viscera (V) of Scophthalmus maximus (SM), Paralichthysi (P), Limanda ferruginea (LF), Cleisthenes herzensteini (G), Platichthys bicoloratus (PB), Pleuronichthys cornutus (PC), and Cleisthenes herzensteini (CH). Unsaturated disaccharide products were obtained by enzymatic hydrolysis of the GAGs and subjected to compositional analysis of chondroitin sulfate (CS), heparin sulfate (HS), and hyaluronic acid (HA), including the sulfation degree of CS and HS, as well as the content of each GAG. The contents of GAGs in the tissues and the sulfation degree differed significantly among the fish. The bone of S. maximus contained more than 12 μg of CS per mg of dry tissue. Although the fish typically contained high levels of CSA (CS-4S), some fish bone tissue exhibited elevated levels of CSC (CS-6S). The HS content was found to range from 10–150 ug/g, primarily distributed in viscera, with a predominant non-sulfated structure (HS-0S). The structure of HA is well-defined without sulfation modification. These analytical results are independent of biological classification. We provide a high-throughput rapid detection method for tissue samples using HPLC-MS/MS to rapidly screen ideal sources of GAG. On this basis, four kinds of CS were prepared and purified from flounder bone, and their molecular weight was determined to be 23–28 kDa by HPGPC-MALLS, and the disaccharide component unit was dominated by CS-6S, which is a potential substitute for CSC derived from shark cartilage. [ABSTRACT FROM AUTHOR]

Autonomous driving technology heavily relies on the accurate perception of traffic environments, mainly through roadside cameras and LiDARs. Although several popular and robust 2D and 3D object detection methods exist, including R-CNN, YOLO, SSD, PointPillar, and VoxelNet, the perception range and accuracy of an individual vehicle can be limited by blocking from other vehicles or buildings. A solution is to harness roadside perception infrastructures for vehicle–infrastructure cooperative perception, using edge computing for real-time intermediate features extraction and V2X networks for transmitting these features to vehicles. This emerging migratory perception paradigm requires deploying exclusive cooperative perception services on edge servers and involves the migration of perception services to reduce response time. In such a setup, competition among multiple cooperative perception services exists due to limited edge resources. This study proposes a multi-agent reinforcement learning (MADRL)-based service scheduling method for migratory perception in vehicle–infrastructure cooperative perception, utilizing a discrete time-varying graph to model the relationship between service nodes and edge server nodes. This MADRL-based approach can efficiently address the challenges of service placement and migration in resource-limited environments, minimize latency, and maximize resource utilization for migratory perception services on edge servers. [ABSTRACT FROM AUTHOR]

A series of twenty-two quinazolinamine derivatives showing potent inhibitory activities on breast cancer resistance protein (BCRP) and p-glycoprotein (P-gp) were synthesized. A cyclopropyl-containing quinazolinamine 22 was identified as a dual BCRP and P-gp inhibitor, while azide-containing quinazolinamine 33 showed BCRP inhibitory activity. These lead compounds were further investigated in a battery of mechanistic experiments. Compound 22 changed the localization of BCRP and P-gp in cells, thus inhibiting the efflux of anticancer drugs by the two ATP-binding cassette (ABC) transporters. In addition, both 22 and 33 significantly stimulated the ATP hydrolysis of the BCRP transporter, indicating that they can be competitive substrates of the BCRP transporter, and thereby increase the accumulation of mitoxantrone in BCRP-overexpressing H460/MX20 cells. Azide derivative 33, exhibited a greater inhibitory effect on BCRP after UV activation and can serve as a valuable probe for investigating the interactions of quinazolinamine derivatives with BCRP. Notably, the dual BCRP and P-gp inhibitors 4–5, 22–24, 27, and BCRP inhibitor 33 showed improved metabolic stability compared to Ko143. [ABSTRACT FROM AUTHOR]

Three-dimensionally printed materials show great performance and reliable stability in the removal of refractory organic pollutants in Fenton-like reactions. In this work, hierarchically porous zero-valent copper (3DHP-ZVC) was designed and fabricated via 3D printing and applied as a catalyst for the degradation of tetracycline (TC) through heterogeneous Fenton-like processes. It was found that the 3DHP-ZVC/H2O2 system could decompose over 93.2% of TC within 60 min, which is much superior to the homogeneous Cu2+/H2O2 system under similar conditions. The leaching concentration of Cu2+ ions in the 3DHP-ZVC/H2O2 system is 2.14 times lower than that in the Cu powder/H2O2 system in a neutral environment, which could be ascribed to the unique hierarchically porous structure of 3DHP-ZVC. Furthermore, 3DHP-ZVC exhibited compelling stability in 20 consecutive cycles. The effects of co-existing inorganic anions, adaptability, and pH resistance on the degradation of TC were also investigated. A series of experiments and characterizations revealed that Cu0 and superoxide radicals as reducing agents could facilitate the cycling of Cu(II)/Cu(I), thus enhancing the generation of hydroxyl radicals to degrade TC. This study provides new insights into employing promising 3D printing technology to develop high-reactivity, stable, and recycling-friendly components for wastewater treatment. [ABSTRACT FROM AUTHOR]

Diffraction algorithms with adjustable magnification are dominant in holographic projection and imaging. However, the algorithms are limited by the Nyquist sampling conditions, and simulation results with inappropriate parameters sometimes appear with aliasing. At present, many diffraction algorithms have been proposed and improved, but there is a need for an overall analysis of their sampling conditions. In this paper, some classical diffraction algorithms with adjustable magnification are summarized, and their sampling conditions in the case of plane wave or spherical wave illumination are analyzed and compared, which helps to select the appropriate diffraction algorithm according to the specific parameter conditions of the simulation to avoid aliasing. [ABSTRACT FROM AUTHOR]

Shijing 詩經 is the earliest collection of Chinese poems and songs traditionally considered to be compiled by Confucius. Scholarship on this collection deems the widespread wind imagery contained in it to be either a metaphor for males or a medium of emotional expression. However, the religious ideas involved in the sacrifices to the wind gods in early China, which are, in fact, deeply linked with the "wind" in Shijing, warrant further consideration. This article focuses on the relation between the "wind" in Shijing and the religious ideas involved in sacrificial rites ("ningfeng 寧風" and "difeng 禘風") to the wind gods. Drawing upon the history of wind disasters and sacrifices to the wind gods in early China, this article suggests that the pieces entitled "Gufeng 谷風" (included in the Xiaoya 小雅 section) and "Herensi 何人斯" provide descriptions of "ningfeng" (appeasing unwanted wind). Moreover, it argues that the pieces entitled "Kaifeng 凱風" and "Tuoxi 蘀兮" depict a genial wind in connection with harvest, childbearing, and prosperity involved in "difeng". [ABSTRACT FROM AUTHOR]

Activated two-dimension (2D) materials are used in various applications as high-performance catalysts. Breaking the long-range order of the basal plane of 2D materials can highly promote catalytic activity by supplying more active sites. Here we developed a method to synthesize ultrathin MCoOx (M = V, Mn, Fe, Ni, Cu, Zn) amorphous nanosheets (ANSs). These Co-based ANSs show high oxygen evolution reaction (OER) activity in alkaline solution due to the broken long-range order and the presence of abundant low bonded O on the basal plane. The stable Fe1Co1Ox ANSs also show an overpotential of ca. 240 mV of achieving 10 mA/cm2 in OER, better than most reported transition metal-based electrocatalysts. [ABSTRACT FROM AUTHOR]

With the rapid development of computer hardware and the emergence of the parallel calculation of diffraction fields, a breakthrough has been made in terms of the limitation of the unacceptable amount of computational cost to design diffractive optical elements (DOEs), and more accurate global search algorithms can be introduced to the design of complex DOEs and holographic projections instead of traditional iterative algorithms. In this paper, a hybrid algorithm which combines particle swarm optimization (PSO) with a simulated annealing (SA) algorithm is proposed for the designing of DOEs and projecting holographic images with less noise. PSO is used to reduce the invalid disturbance in SA, and SA can jump out from local extreme points to find the global extreme points. Compared with the traditional Gerchberg–Saxton (GS) algorithm, the simulation and experimental results demonstrate that the proposed SA–PSO hybrid algorithm can improve uniformity by more than 10%. [ABSTRACT FROM AUTHOR]

Three oil-miscible phosphonium ionic liquids with different structures were synthesized and used as additives for a Poly Alpha Olefin 10 (PAO 10) lithium lubricating grease. Different from other additives, the ionic liquids participated in saponification and were trapped in the entanglement network formed by the thickener. The effects of the ionic liquids on the rheological properties of lithium lubricating grease were characterized through a small-amplitude oscillatory shear (SAOS) measurement. The tribological performances of the lubricating greases were determined on a four-ball friction tester. The addition of phosphonium ionic liquids caused a decrease in the storage (G') and loss (G") modulus of lubricating grease. However, the ionic liquids were found to be effective lubricant additives for improving the friction-reducing and antiwear properties of PAO 10 lithium lubricating grease. [ABSTRACT FROM AUTHOR]

Nickel-based selenides are believed to be promising non-precious metal electrocatalysts, and have been widely used for both oxygen evolution reactions (OER) and hydrogen evolution reactions (HER). Here, we control the aging time to prepare NixSey with different fractal structures as a bifunctional catalyst. An obtained sample with an aging time of 80 min shows outstanding electrocatalytic performance for hydrogen evolution reactions (HER) with an overpotential of 225 mV (η@10 mA/cm2) and for oxygen evolution reactions (OER) with an overpotential of 309 mV (η@50 mA/cm2). Moreover, to further improve catalytic activity, we doped Fe in NixSey to obtain the ternary nickel-based selenide, Fe0.2Ni0.8Se (FNSs). The HER activity of FNS increased two-fold at 10 mA/cm2, and the overpotential of OER decreased to 255 mV at 50 mA/cm2. The synthetic strategy and research results of this work have a certain reference value for other low-cost and high-efficiency transition metal catalysts for electrocatalytic water splitting. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing (HF) is an effective technology to prevent and control coal dynamic disaster. The process of coal hydraulic fracturing (HF) induces a large number of microseismic/acoustic emission (MS/AE) waveforms. Understanding the characteristic of AE waveforms' parameters is essential for evaluating the fracturing effect and optimizing the HF strategy in coal formation. In this study, laboratory hydraulic fracturing under true triaxial stress was performed on a cubic coal sample combined with AE monitoring. The injection pressure curve and temporal variation of AE waveforms' parameters in different stages were analyzed in detail. The experimental results show that the characteristics of the AE waveforms' parameters well reflect the HF growth behavior in coal. The majority of AE waveforms' dominant frequency is distributed between 145 and 160 kHz during HF. The sharp decrease of the injection pressure curve and the sharp increase of the AE waveforms' amplitude show that the fracture already runs through the coal sample during the initial fracture stage. The "trapezoidal" rise pattern of cumulative energy and most AE waveforms with low amplitude may indicate the stage of liquid storage space expansion. The largest proportion of AE waveforms' energy and higher overall level of AE waveforms' amplitude occur during the secondary fracture stage, which indicates the most severe degree of coal fracture and complex activity of internal fracture. The phenomenon shows the difference in fracture mechanism between the initial and secondary fracture stage. We propose a window-number index of AE waveforms for better response to hydraulic fracture, which can improve the accuracy of the HF process division. [ABSTRACT FROM AUTHOR]

Simple Summary: Multidrug resistance or chemoresistance is a phenomenon where cells exhibit resistance to drugs that are pharmacologically and structurally distinct. ABCG2, a member of ABC transporter superfamily has been widely reported to be a principal cause of MDR in various cancers via pumping out various antineoplastic drugs. VKNG-1, a phenyltetrazole analogue selectively inhibits the ABCG2 transporter and reverses resistance to standard anticancer drugs both in vitro and in vivo in ABCG2-overexpressing colon cancers. This study presents the importance of VKNG-1 as a modulator of the ABCG2 transporter. In cancer patients, a combination of VKNG-1 and ABCG2 substrate drugs could be a beneficial treatment option for cells with high ABCG2 expression. The emergence of multidrug resistance (MDR) to chemotherapeutic drugs is a major problem in the therapy of cancer. Knowledge of the mechanisms of drug resistance in cancer is necessary for developing efficacious therapies. ATP-binding cassette (ABC) transporters are transmembrane proteins that efflux chemotherapeutic drugs from cancer cells, thereby producing MDR. Our research efforts have led to the discovery of VKNG-1, a compound that selectively inhibits the ABCG2 transporter and reverses resistanctabe to standard anticancer drugs both in vitro and in vivo. VKNG-1, at 6 µM, selectively inhibited ABCG2 transporter and sensitized ABCG2-overexpressing drug-resistant cancer cells to the ABCG2 substrate anticancer drugs mitoxantrone, SN-38, and doxorubicin in ABCG2-overexpressing colon cancers. VKNG- 1 reverses ABCG2-mediated MDR by blocking ABCG2 efflux activity and downregulating ABCG2 expression at the mRNA and protein levels. Moreover, VKNG-1 inhibits the level of phosphorylated protein kinase B (PKB/p-AKT), and B-cell lymphoma-2 (Bcl-2) protein which may overcome resistance to anticancer drugs. However, the in vitro translocation of ABCG2 protein did not occur in the presence of 6 µM of VKNG-1. In addition, VKNG-1 enhanced the anticancer efficacy of irinotecan in ABCG2- overexpressing mouse tumor xenografts. Overall, our results suggest that VKNG-1 may, in combination with certain anticancer drugs, represent a treatment to overcome ABCG2-mediated MDR colon cancers. [ABSTRACT FROM AUTHOR]

This paper proposes a university teachers' teaching performance evaluation method based on type-II fuzzy sets (T2 FSs), which solves the problems of fuzziness, complexity and uncertainty in teaching performance evaluation. Firstly, the evaluation indicator system is constructed from the aspects of teaching attitude, teaching contents, teaching professionalism, teaching methods and teaching effects. Then, T2 FSs theory and the perceptual computing method are introduced to model subjective judgments and capture uncertainties, effectively handling higher levels of uncertainty in the evaluation process. Furthermore, the linguistic weighted average operator is applied as the computing with words engine to aggregate scores and weights of indicators, which effectively integrates the uncertain information in the input data into the final evaluation conclusion and guarantees the accuracy of the evaluation results. Finally, the effectiveness of the method of this study is evaluated by simulation experiments. The computational results demonstrate that it can capture more uncertain and complex information, and is more accurate and reliable than the type-I fuzzy sets method. [ABSTRACT FROM AUTHOR]

Multi Jet Fusion (MJF) is a recently developed polymeric powder bed fusion (PBF) additive manufacturing technique that has received considerable attention in the industrial and scientific community due to its ability to fabricate functional and complex polymeric parts efficiently. In this work, a systematic characterization of the physicochemical properties of MJF-certified polyamide 11 (PA11) and thermoplastic polyurethane (TPU) powder was conducted. The mechanical performance and print quality of the specimens printed using both powders were then evaluated. Both PA11 and TPU powders showed irregular morphology with sharp features and had broad particle size distribution, but such features did not impair their printability significantly. According to the DSC scans, the PA11 specimen exhibited two endothermic peaks, while the TPU specimen exhibited a broad endothermic peak (116–150 °C). The PA11 specimens possessed the highest tensile strength in the Z orientation, as opposed to the TPU specimens which possessed the lowest tensile strength along the same orientation. The flexural properties of the PA11 and TPU specimens displayed a similar anisotropy where the flexural strength was highest in the Z orientation and lowest in the X orientation. The porosity values of both the PA11 and the TPU specimens were observed to be the lowest in the Z orientation and highest in the X orientation, which was the opposite of the trend observed for the flexural strength of the specimens. The PA11 specimen possessed a low coefficient of friction (COF) of 0.13 and wear rate of 8.68 × 10−5 mm3/Nm as compared to the TPU specimen, which had a COF of 0.55 and wear rate of 0.012 mm3/Nm. The PA11 specimens generally had lower roughness values on their surfaces (Ra < 25 μ m), while the TPU specimens had much rougher surfaces (Ra > 40 μ m). This investigation aims to uncover and explain phenomena that are unique to the MJF process of PA11 and TPU while also serving as a benchmark against similar polymeric parts printed using other PBF processes. [ABSTRACT FROM AUTHOR]

Multiple blind sound source localization is the key technology for a myriad of applications such as robotic navigation and indoor localization. However, existing solutions can only locate a few sound sources simultaneously due to the limitation imposed by the number of microphones in an array. To this end, this paper proposes a novel multiple blind sound source localization algorithms using Source seParation and BeamForming (SPBF). Our algorithm overcomes the limitations of existing solutions and can locate more blind sources than the number of microphones in an array. Specifically, we propose a novel microphone layout, enabling salient multiple source separation while still preserving their arrival time information. After then, we perform source localization via beamforming using each demixed source. Such a design allows minimizing mutual interference from different sound sources, thereby enabling finer AoA estimation. To further enhance localization performance, we design a new spectral weighting function that can enhance the signal-to-noise-ratio, allowing a relatively narrow beam and thus finer angle of arrival estimation. Simulation experiments under typical indoor situations demonstrate a maximum of only 4 ∘ even under up to 14 sources. [ABSTRACT FROM AUTHOR]

Injectable hydrogels have attracted growing interests as promising biomaterials for clinical applications, due to their minimum invasive implanting approach and easy-handling performance. Nevertheless, natural biomaterials-based injectable hydrogels with desirable nontoxicity are suffering from limited functions, failing to fulfill the requirements of clinical biomaterials. The development of novel injectable biomaterials with a combination of biocompatibility and adequate functional properties is a growing urgency toward biomedical applications. In this contribution, we report a simple and effective approach to fabricate multi-functional CMC-OSA-DTP hydrogels. Two kinds of natural polysaccharide derived polymers, carboxymethyl chitosan (CMC) and oxidized alginate (OSA) along with 3,3′-dithiopropionic acid dihydrazide (DTP) were utilized to introduce three dynamic covalent bonds. Owing to the existence of triple dynamic bonds, this unique CMC-OSA-DTP hydrogel possessed smart redox and pH stimuli-responsive property, injectability as well as self-healing ability. In addition, the CCK-8 and live/dead assays demonstrated satisfying cytocompatibility of the CMC-OSA-DTP hydrogel in vitro. Based on its attractive properties, this easy-fabricated and multi-functional hydrogel demonstrated the great potential as an injectable biomaterial in a variety of biomedical applications. [ABSTRACT FROM AUTHOR]

The overexpressing ABCB1 transporter is one of the key factors leading to multidrug resistance (MDR). Thus, many ABCB1 inhibitors have been found to be able to overcome ABCB1-mediated MDR. However, some inhibitors also work as a substrate of ABCB1, which indicates that in order to achieve an effective reversal dosage, a higher concentration is needed to overcome the pumped function of ABCB1, which may concurrently increase the toxicity. WYE-354 is an effective and specific mTOR (mammalian target of rapamycin) inhibitor, which recently has been reported to reverse ABCB1-mediated MDR. In the current study, 3-(4,5-dimethylthiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay was carried out to determine the cell viability and reversal effect of WYE-354 in parental and drug-resistant cells. Drug accumulation was performed to examine the effect of WYE-354 on the cellular accumulation of chemotherapeutic drugs. The ATPase (adenosine triphosphatase) activity of the ABCB1 transporter in the presence or absence of WYE-354 was conducted in order to determine the impact of WYE-354 on ATP hydrolysis. Western blot analysis and immunofluorescence assay were used to investigate the protein molecules related to MDR. In addition, the interaction between the WYE-354 and ABCB1 transporter was investigated via in silico analysis. We demonstrated that WYE-354 is a substrate of ABCB1, that the overexpression of the ABCB1 transporter decreases the efficacy of WYE-354, and that the resistant WYE-354 can be reversed by an ABCB1 inhibitor at a pharmacological achievable concentration. Furthermore, WYE-354 increased the intracellular accumulation of paclitaxel in the ABCB1-mediated MDR cell line, without affecting the corresponding parental cell line, which indicated that WYE-354 could compete with other chemotherapeutic drugs for the ABCB1 transporter substrate binding site. In addition, WYE-354 received a high score in the docking analysis, indicating a strong interaction between WYE-354 and the ABCB1 transporter. The results of the ATPase analysis showed that WYE-354 could stimulate ABCB1 ATPase activity. Treatment with WYE-354 did not affect the protein expression or subcellular localization of the ABCB1. This study provides evidence that WYE-354 is a substrate of the ABCB1 transporter, implicating that WYE-354 should be avoided for use in ABCB1-mediated MDR cancer. [ABSTRACT FROM AUTHOR]

The overexpression of ABC transporters induced by anticancer drugs has been found to be the main cause of multidrug resistance. It is actually also a strategy by which cancer cells escape being killed. Tetrandrine is a natural product extracted from the stem of Tinospora crispa. In this study, tetrandrine showed synergistic cytotoxic activity in combinational use with chemotherapeutic drugs, such as Doxorubicin, Vincristine, and Paclitaxel, in both drug-induced and MDR1 gene-transfected cancer cells that over-expressed ABCB1/P-glycoprotein. Tetrandrine stimulated P-glycoprotein ATPase activity, decreased the efflux of [3H]-Paclitaxel and increased the intracellular accumulation of [3H]-Paclitaxel in KB-C2 cells. Furthermore, SW620/Ad300 and KB-C2 cells pretreated with 1 μM tetrandrine for 72 h decreased P-glycoprotein expression without changing its cellular localization. This was demonstrated through Western blotting and immunofluorescence analysis. Interestingly, down-regulation of P-glycoprotein expression was not correlated with gene transcription, as the MDR1 mRNA level exhibited a slight fluctuation in SW620/Ad300 and KB-C2 cells at 0, 24, 48, and 72 h treatment time points. In addition, molecular docking analysis predicted that tetrandrine had inhibitory potential with the ABCB1 transporter. Our results suggested that tetrandrine can antagonize MDR in both drug-selected and MDR1 gene-transfected cancer cells by down regulating the expression of the ABCB1 transporter, followed by increasing the intracellular concentration of chemotherapeutic agents. The combinational therapy using tetrandrine and other anticancer drugs could promote the treatment efficiency of drugs that are substrates of ABCB1. [ABSTRACT FROM AUTHOR]

Recent studies have reported that dietary fiber improved metabolic syndrome (MetS). However, the effects of fucoidans on MetS were still not clear. In this study, we evaluated the activity of fucoidan from Fucus vesiculosus (FvF) on attenuating MetS and first elucidated the underlying mechanism. In vitro, FvF treatment remarkably lowered the level of reactive oxygen species (ROS) compared with the sodium palmitate (PA)-induced insulin resistance (IR) group. The phosphorylation level of c-Jun N-terminal kinase (JNK) was significantly decreased, while phosphorylation of protein kinase B (pAkt) level increased, compared with that of the HepG2 cells treated with PA. Thus, FvF increased glucose consumption and relieved IR via ROS-mediated JNK and Akt signaling pathways. In addition, these changes were accompanied by the activation of adenosine 5′-monophosphate-ativated protein kinase (AMPK) and its downstream targets (e.g., HMG-CoA reductase (HMGCR), acetyl-CoA carboxylase (ACC), and sterol-regulatory element-binding protein-1c (SREBP-1C)), which improved lipid metabolism in IR HepG2 cells. In vivo, FvF improved hyperglycemia and decreased serum insulin level in mice with MetS. Furthermore, we evaluated the inhibition of glucose transport by in vitro (Caco-2 monolayer model), semi-in vivo (everted gut sac model) and oral glucose tolerance test (OGTT), which indicated that FvF could significantly reduce the absorption of glucose into the blood stream, thus it could improve blood-glucose levels and IR in mice with MetS. Moreover, FvF decreased serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) levels and liver lipid accumulation, while increased the serum high density lipoprotein cholesterol (HDL-C) level in mice with MetS. Therefore, FvF could be considered as a potential candidate for the treatment of MetS by alleviating IR, inhibiting glucose transportation, and regulating lipid metabolism. [ABSTRACT FROM AUTHOR]

P-glycoprotein (P-gp), which is encoded by the ATP-binding cassette (ABC) transporter subfamily B member 1 (ABCB1) gene, is one of the most pivotal ABC transporters that transport its substrates across the cell membrane. Its overexpression is one of the confirmed causes of multidrug resistance (MDR), which results in the failure of cancer treatment. Here, we report that checkpoint kinase (Chk) 1 inhibitor MK-8776, a drug candidate in clinical trial, can restore the sensitivity of chemotherapeutics that are substrates of P-gp in KB-C2, SW620/Ad300 cells and human embryonic kidney (HEK)293/ABCB1 cells that overexpress P-gp. MK-8776 remarkably enhanced the cellular [3H]-paclitaxel accumulation and suppressed the efflux function of P-gp without reducing its expression and affecting its cellular localization in cancer cells. Furthermore, MK-8776 (0–40 μM) stimulated the activity of ATPase in P-gp, which was 4.1-fold greater than the control. In addition, MK-8776 formed a cation–π bond and π–π interaction with key residues of the substrate-binding site in P-gp, as indicated by computer-aided molecular docking study. Our study indicated that MK-8776 may significantly enhance the sensitivity of chemotherapeutics that are substrates of P-gp, providing important information for its application in the reversal of MDR. [ABSTRACT FROM AUTHOR]

The purpose of this study is to develop a robust approach to obtain β glucans from Lentinus edodes and to characterize their structural and biological properties for sustainable utilization. The alkali extraction was optimized with an orthogonal experimental design, and a concise process for obtaining specific targeting polysaccharides from Lentinus edodes was developed in this study. After purification with a Q-Sepharose Fast Flow strong anion-exchange column, the monosaccharide composition, a methylation analysis, and NMR spectroscopy were employed for their structural characterizations. LeP-N2 was found to be composed of (1→6)-β-d-glucans with minor β-(1→3) glucosidic side chains. Atomic force microscopy (AFM) and high-performance gel permeation chromatography–refractive index–multi-angle laser light scattering (HPGPC-RI-MALLS) also revealed LeP-N2 exhibiting a compact unit in aqueous solution. This (1→6)-β-d-glucan was tested for antioxidant activities with IC50 at 157 μg/mL. Moreover, RAW 264.7 macrophage activation indicated that the release of nitric oxide (NO) and reactive oxygen species (ROS) were markedly increased with no cytotoxicity at a dose of 100 μg/mL. These findings suggest that the (1→6)-β-d-glucans obtained from Lentinus edodes could serve as potential agents in the fields of functional foods or medicine. [ABSTRACT FROM AUTHOR]

In this study, glass fiber (GF)/phenol formaldehyde resin (PF)/epoxy resin (EP) three-phase electrical insulating composites were fabricated by selective laser sintering (SLS) additive manufacturing technology and subsequent infiltration. In the three-phase composites, glass fibers modified by a silane coupling agent (KH-550) were used as reinforcements, phenol formaldehyde resin acted as the binder and matrix, and infiltrated epoxy resin was the filler. Mechanical and electrical properties such as tensile strength, bending strength, dielectric constant, electrical conductivity, and electric breakdown strength of the GF/PF/EP three-phase composite parts were investigated. The results indicated that after being infiltrated with EP, the bending strength and tensile strength of the GF/PF/EP composites increased by 30% and 42.8%, respectively. Moreover, the flexural strength and tensile strength of the GF/PF/EP composite increased with the increase of the glass fiber content. More importantly, the three-phase composites showed high electrical properties. Significant improvement in the dielectric constant, electric breakdown strength, and resistivity with the increase in the content of glass fiber was observed. This enables the prepared GF/PF/EP composites to form complex structural electrical insulation devices by SLS, which expands the materials and applications of additive manufacturing technology. [ABSTRACT FROM AUTHOR]

Porous phosphide NixCoyP composite nanomaterials are successfully synthesized at different Ni/Co ratios (=0, 0.5, 1, and 2) to reduce 4-nitrophenol. The X-ray diffraction and X-ray photoelectron spectroscopy results demonstrate that the products are CoP, NiCoP/CoP, NiCoP, and NiCoP/Ni2P when the Ni/Co ratio is 0, 0.5, 1, and 2, respectively. The products exhibit different catalytic performance for reduction of 4-nitrophenol at room temperature. Among them, the pure NiCoP delivers a better catalytic efficiency with k app = 677.4 × 10 − 2   min − 1 and k = 338.7   ( Lg − 1 min − 1 ) , due to the synergy between Ni and Co atoms. The sequence of catalytic efficiency of different samples is CoP < NiCoP/CoP < NiCoP/Ni2P < NiCoP. [ABSTRACT FROM AUTHOR]

This review discusses different forms of nanomaterials generated from chitosan and its derivatives for controlled drug delivery. Nanomaterials are drug carriers with multiple features, including target delivery triggered by environmental, pH, thermal responses, enhanced biocompatibility, and the ability to cross the blood-brain barrier. Chitosan (CS), a natural polysaccharide largely obtained from marine crustaceans, is a promising drug delivery vector for therapeutics and diagnostics, owing to its biocompatibility, biodegradability, low toxicity, and structural variability. This review describes various approaches to obtain novel CS derivatives, including their distinct advantages, as well as different forms of nanomaterials recently developed from CS. The advanced applications of CS-based nanomaterials are presented here in terms of their specific functions. Recent studies have proven that nanotechnology combined with CS and its derivatives could potentially circumvent obstacles in the transport of drugs thereby improving the drug efficacy. CS-based nanomaterials have been shown to be highly effective in targeted drug therapy. [ABSTRACT FROM AUTHOR]

Recently, accumulating evidence has suggested that Enteromorpha clathrata polysaccharide (ECP) could contribute to the treatment of diseases. However, as a promising candidate for marine drug development, although ECP has been extensively studied, less consideration has been given to exploring its effect on gut microbiota. In this light, given the critical role of gut microbiota in health and disease, we investigated here the effect of ECP on gut microbiota using 16S rRNA high-throughput sequencing. As revealed by bioinformatic analyses, ECP considerably changed the structure of the gut microbiota and significantly promoted the growth of probiotic bacteria in C57BL/6J mice. However, interestingly, ECP exerted different effects on male and female microbiota. In females, ECP increased the abundances of Bifidobacterium spp. and Akkermansia muciniphila, a next-generation probiotic bacterium, whereas in males, ECP increased the population of Lactobacillus spp. Moreover, by shaping a more balanced structure of the microbiota, ECP remarkably reduced the antigen load from the gut in females. Altogether, our study demonstrates for the first time a prebiotic effect of ECP on gut microbiota and forms the basis for the development of ECP as a novel gut microbiota modulator for health promotion and disease management. [ABSTRACT FROM AUTHOR]

As an important glycosaminoglycan, keratan sulfate (KS) mainly exists in corneal and cartilage, possessing various biological activities. In this study, we purified KS from blue shark (Prionace glauca) cartilage and prepared KS oligosaccharides (KSO) through keratanase II-catalyzed hydrolysis. The structures of KS and KSO were characterized using multi-dimensional nuclear magnetic resonance (NMR) spectra and liquid chromatography-mass spectrometry (LC-MS). Shark cartilage KS was highly sulfated and modified with ~2.69% N-acetylneuraminic acid (NeuAc) through α(2,3)-linked to galactose. Additionally, KS exhibited binding affinity to Ricinus communis agglutinin I (RCA120) in a concentration-dependent manner, a highly toxic lectin from beans of the castor plant. Furthermore, KSO from dp2 to dp8 bound to RCA120 in the increasing trend while the binding affinity of dp8 was superior to polysaccharide. These results define novel structural features for KS from Prionace glauca cartilage and demonstrate the potential application on ricin-antidote exploitation. [ABSTRACT FROM AUTHOR]

We previously demonstrated that fucoidan with a type II structure inhibited postprandial hyperglycemia by suppressing glucose uptake, but the mechanism remains elusive. Here, we aimed to assess whether the effect of glucose absorption inhibition was related to the basic structure of fucoidans and preliminarily clarified the underlying mechanism. Fucoidans with type II structure and type I structure were prepared from Ascophyllum nodosum (AnF) or Laminaria japonica (LjF) and Kjellmaniella crassifolia (KcF), respectively. The effects of various fucoidans on suppressing postprandial hyperglycemia were investigated using in vitro (Caco-2 monolayer model), semi-in vivo (everted gut sac model), and in vivo (oral glucose tolerance test, OGTT) assays. The results showed that only AnF with a type II structure, but not LjF or KcF with type I structure, could inhibit the glucose transport in the Caco-2 monolayer and everted gut sac models. A similar result was seen in the OGTT of Kunming mice and leptin receptor-deficient (db/db) mice, where only AnF could effectively inhibit glucose transport into the bloodstream. Furthermore, AnF (400 mg/kg/d) treatment decreased the fasting blood glucose, HbA1c, and fasting insulin levels, while increasing the serum glucagon-like peptide-1 (GLP-1) level in obese leptin receptor-deficient (db/db) mice. Furthermore, surface plasmon resonance (SPR) analysis revealed the specific binding of AnF to Na + /glucose cotransporter 1 (SGLT1), which indicated the effect of AnF on postprandial hyperglycemia could be due to its suppression on SGLT1 activity. Taken together, this study suggests that AnF with a type II structure can be a promising candidate for hyperglycemia treatment.

As an important glycosaminoglycan, keratan sulfate (KS) mainly exists in corneal and cartilage, possessing various biological activities. In this study, we purified KS from blue shark ( Prionace glauca ) cartilage and prepared KS oligosaccharides (KSO) through keratanase II-catalyzed hydrolysis. The structures of KS and KSO were characterized using multi-dimensional nuclear magnetic resonance (NMR) spectra and liquid chromatography-mass spectrometry (LC-MS). Shark cartilage KS was highly sulfated and modified with ~2.69% N -acetylneuraminic acid (NeuAc) through α(2,3)-linked to galactose. Additionally, KS exhibited binding affinity to Ricinus communis agglutinin I (RCA 120 ) in a concentration-dependent manner, a highly toxic lectin from beans of the castor plant. Furthermore, KSO from dp2 to dp8 bound to RCA 120 in the increasing trend while the binding affinity of dp8 was superior to polysaccharide. These results define novel structural features for KS from Prionace glauca cartilage and demonstrate the potential application on ricin-antidote exploitation., Competing Interests: The authors declare no conflict of interest.

Keratan sulfate (KS) represents an important family of glycosaminoglycans that are critical in diverse physiological processes. Recently, accumulating evidence has provided a wealth of information on the bioactivity of KS, which established it as an attractive candidate for drug development. However, although KS has been widely explored, less attention has been given to its effect on gut microbiota. Therefore, given that gut microbiota plays a pivotal role in health homeostasis and disease pathogenesis, we investigated here in detail the effect of KS on gut microbiota by high-throughput sequencing. As revealed by heatmap and principal component analysis, the mice gut microbiota was readily altered at different taxonomic levels by intake of low (8 mg/kg) and high dosage (40 mg/kg) of KS. Interestingly, KS exerted a differing effect on male and female microbiota. Specifically, KS induced a much more drastic increase in the abundance of Lactobacillus spp. in female (sixteen-fold) versus male mice (two-fold). In addition, combined with alterations in gut microbiota, KS also significantly reduced body weight while maintaining normal gut homeostasis. Altogether, we first demonstrated a sex-dependent effect of KS on gut microbiota and highlighted that it may be used as a novel prebiotic for disease management., Competing Interests: The authors declare no conflict of interest.

Streptococcus gallolyticus subsp. pasteurianus is an under-recognized pathogen and zoonotic agent causing opportunistic infections in humans. Despite increasing recognition of this subspecies as a cause for human infectious diseases, limited information is known about its antibiotic resistance mechanism. In this study, we aim to identify the molecular mechanism underlying the high macrolide resistance of six S. gallolyticus subsp. pasteurianus isolates from dead ducklings collected in several natural outbreaks in China during 2010-2013. All isolates exhibited multi-drug resistance including high macrolide resistance (MIC ≥ 1024 mg/L for erythromycin, and 512 mg/L for clarithromycin). Efflux-encoding mefA and mefE genes were not detectable in these isolates. The presence of 23S rRNA mutations in specific isolates did not significantly change macrolide MICs. No nucleotide substitutions were found in genes encoding ribosomal proteins L4 or L22. The ermB and ermT genes were found in the genomes of all isolates. These two genes were acquired independently in one highly virulent isolate AL101002, and clustered with Tn916 and IS1216, respectively. The expression of both ermB and ermT in all isolates was erythromycin inducible and yielded comparable macrolide MICs in all six isolates. Taken together, inducible expression of both ermB and ermT conferred high macrolide resistance in these S. gallolyticus subsp. pasterianus isolates. Our findings reveal new macrolide resistance features in S. gallolyticus subsp. pasteurianus by both ermB and ermT., Competing Interests: The authors declare no competing interests.

The low-molecular-weight fucosylated chondroitin sulfate (LFCS) was prepared from native fucosylated chondroitin sulfate (FCS), which was extracted and isolated from sea cucumber Cucumaria frondosa, and the anti-cancer mechanism of LFCS on mouse Lewis lung carcinoma (LLC) was investigated. The results showed that LFCS remarkably inhibited LLC growth and metastasis in a dose-dependent manner. LFCS induced cell cycle arrest by increasing p53/p21 expression and apoptosis through activation of caspase-3 activity in LLC cells. Meanwhile, LFCS suppressed the expression of vascular endothelial growth factor (VEGF), increased the expression of tissue inhibitor of metalloproteinase-1 (TIMP-1) and downregulated the matrix metalloproteinases (MMPs) level. Furthermore, LFCS significantly suppressed the activation of ERK1/2/p38 MAPK/NF-κB pathway, which played a prime role in expression of MMPs. All of these data indicate LFCS may be used as anti-cancer drug candidates and deserve further study.

An apigalacturonan (AGA)-rich polysaccharide, ZCMP, was isolated from the sea grass Zostera caespitosa Miki. The depolymerized fragments derived from ZCMP were obtained by either acidic degradation or pectinase degradation, and their structures were characterized by electrospray ionization collision-induced-dissociation mass spectrometry (ESI-CID-MS2) and nuclear magnetic resonance (NMR) spectroscopy. The average molecular weight of ZCMP was 77.2 kD and it consisted of galacturonic acid (GalA), apiosefuranose (Api), galactose (Gal), rhamnose (Rha), arabinose (Ara), xylose (Xyl), and mannose (Man), at a molar ratio of 51.4꞉15.5꞉6.0꞉11.8꞉4.2꞉4.4꞉4.2. There were two regions of AGA (70%) and rhamnogalacturonan-I (RG-Ι, 30%) in ZCMP. AGA was composed of an α-1,4-D-galactopyranosyluronan backbone mainly substituted at the O-3 position by single Api residues. RG-Ι possessed a backbone of repeating disaccharide units of →4GalAα1,2Rhaα1→, with a few α-L-arabinose and β-D-galactose residues as side chains. The anti-angiogenesis assay showed that ZCMP inhibited the migratory activity of human umbilical vein endothelial cell (HUVECs), with no influence on endothelial cells growth. ZCMP also promoted macrophage phagocytosis. These findings of the present study demonstrated the potential anti-tumor activity of ZCMP through anti-angiogenic and immunoregulatory pathways.