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An atomic-scaled Fe2O3/Cu interface loaded catalyst has been prepared for oxygen reduction reaction. The interfaces efficiently modulated the electronic structure to endow the Cu atoms with slight positive charge, which is also active for the ORR.

In this work, RLWPF (Arg-Leu-Trp-Pro-Phe) and VLRLF (Val-Leu-Arg-Leu-Phe) were investigated for the effects against d-galactose (d-gal) induced cognitive impairment by modulating the gut microbiota composition.

The anti-inflammatory effect of the interaction between ellagic acid (EA) and a bioactive tripeptide (FPL) from walnut meal was investigated in this study. We found that lipopolysaccharide (LPS) -induced expression of nitric oxide, tumor necrosis factor-α, interleukin-6, and interleukin-1β were significantly inhibited by the interaction of EA and FPL in RAW264.7 macrophage cells. Cell viability assays and CompuSyn simulations predicted the highest synergistic effect of the combination at doses of EA-25 µM and FPL-100 µM, with the lowest combination index (CI) values reaching 0.56. Fluorescence spectra revealed the intrinsic fluorescence of phenylalanine in FPL was quenched by interaction with EA. Fourier transform infrared spectroscopy indicated FPL had electrostatic and hydrophobic interactions with EA through N-H, C = O, C-N bonds and the secondary structure of FPL had effectively changed, with a decrease in α-helix when interacting with EA. Our results demonstrated that the synergistic anti-inflammatory effect of EA and FPL as potential inflammatory inhibitors in food industry.

Background The majority of global population suffer from various functional gastrointestinal disorders. Pugionium cornutum (L.) Gaertn. (PCG) is used to relieve indigestive symptoms in traditional Chinese medicine. However, little is known about the effects of bioactive components from PCG extracts on gastrointestinal motility. Methods Crude ethanol extract of PCG (EEP) was prepared from Pugionium cornutum (L.) Gaertn. Different solvents were used to prepare fine extracts from EEP, including water extract of PCG (WEP), petroleum ether extract of PCG (PEEP), dichloromethane extract of PCG (DEP) and ethyl acetate extract of PCG (EAEP). Smooth muscle cell model and colonic smooth muscle stripe model were used to test the bioactive effects and mechanisms of different PCG extracts on contraction and relaxation. Diverse chromatographic methods were used to identify bioactive substances from PCG extracts. Results EEP was found to promote the relaxation of gastric smooth muscle cell and inhibit the contraction of colonic smooth muscle strip. Among the fractions of EEP, EAEP mainly mediated the relaxation effect by stimulating intracellular calcium influx. Further evidences revealed that EAEP was antagonistic to acetylcholine. In addition, COX and NO-GC-PKC pathways may be also involved in EAEP-mediated relaxation effect. Quercetin was identified as a bioactive compound from PCG extract for the relaxation effect. Conclusion Our research supports the notion that PCG extracts promote relaxation and inhibits contraction of gastrointestinal smooth muscle at least partially through the effect from quercetin.

Walnut meal is a by-product produced during the production of walnut oil and is often treated as a waste. However, the nutrients in walnut meal mean it has significant potential for development as a plant-based milk. This study investigated the effect of microfluidization on the stability of walnut protein emulsion (WPE) and walnut protein beverage (WPB) produced from walnut meal, compared with conventional homogenization. The particle size, zeta potential, rheological properties, and stability of WPE all significantly improved after microfluidization. The mean particle size and zeta potential of the microfluidized WPE significantly decreased (p < 0.05). The rheological properties demonstrated that the viscosity of the microfluidized WPE decreased by 80%, and that the shear force increased 4.5 times as the shear rate increased. This gave the resulting product the characteristics of non-Newtonian fluid. LUMisizer stability demonstrated that microfluidization improves stability through protein absorption on the oil-water interface. Microfluidization increased the denaturation temperature (Tm) of WPE from 135.65℃ to 154.87℃. Moreover, microfluidization improved the color, centrifugal precipitation rate, and viscosity in WPB compared to the control at all studied temperatures. The Arrhenius approach was used to establish a shelf-life model, which predicted that microfluidized WPB could be stored for 175 d at 4℃.

Peptides are considered promising sources of nutraceuticals. In this study, a mixture of peptides was prepared from Paeonia ostii 'Feng Dan' seed meal protein by continuous enzymolysis. Successive separation and purification procedures, including ultrafiltration and reversed-phase high-performance liquid chromatography (RP-HPLC), were performed, and six novel peptides were identified by liquid chromatography-electrospray ionization source-mass spectrometry/mass spectrometry (LC-ESI-MS/MS). In an in vitro antidiabetic activity test, Tyr-Phe-Phe-Met exhibited stronger α-glucosidase inhibitory activity (48.17 ± 3.34% at 1 mg/mL) than the other peptides. Docking studies of this peptide into the active site of α-glucosidase showed that the formation of hydrogen bonds could be critical for the enzymatic trapping of inhibitory peptides. Furthermore, two novel peptides, Phe-Phe-Phe-Met (IC

Metal-organic frameworks (MOFs) have been widely used as precursors to derive carbon-based electrocatalysts for the oxygen reduction reaction (ORR) due to their high porosity and tunable chemical composition/structure. However, the influence of MOF type on the structure and further ORR activity of derived metal-free carbon catalysts is still elusive. In the present work, a series of different Zn-based MOFs were employed as precursors to explore this issue. Meanwhile, prepare N-doped metal-free carbon catalysts were prepared for the ORR under the activation of sacrificial urea (which is effective to enhance the ORR activity of carbon-based catalysts). By analyzing the intermediates during pyrolysis, it is found that the decisive role of MOF types on the doped N and the morphology of derived carbon catalysts was played by the Zn coordination environment of MOFs and its reactivity with the decomposition intermediate of urea. Although the structure and porosity of derived carbon catalysts from different MOFs are very different, they all showed superior ORR activity and Zn-air battery performance up to 20 wt% Pt/C benchmark catalysts. From the above analyses, the combination of urea and compounded Zn is also a promising activation method for the preparation of highly-efficient metal-free carbon electrocatalysts.

Non-noble metal Ni and its alloy based catalysts are promising alternatives to Pt catalysts for the oxygen reduction reaction (ORR). Control of the exposed crystallographic facets of catalysts is an efficient way of tailoring their activity, but the practicability and the investigation of the underlying mechanisms of this protocol still present challenges for Ni and its alloys. Herein, we succeeded in preparing Ni–Fe alloy nanoparticles (NPs) with different exposed facets via pyrolysis of Fe-substituted Ni-bispyrazolate metal–organic frameworks. Fe-doping induces divergent growth in the two kinds of NPs to afford separate (111)- and (200)-faceted NPs with distinguishable diameters. Density functional theory (DFT) calculations were used to simulate the ORR process on the two facets of the Ni–Fe NPs, revealing that the (200)-faceted NPs show the highest activity due to their large compressive strain effect. The experimental results confirm the enhanced ORR activity of the derived catalysts and superior performance of assembled Zn–air batteries.

The coupling of CO2 and epoxides to form cyclic carbonates has been industrialized since the 1960s. The employment of an efficient and low-cost catalyst is one of the decisive factors to improve the production efficiency. Many catalysts with high activities have been developed; however, those that can convert CO2 and epoxides into cyclic carbonates in a short time or with high efficiency are still less reported. In this study, we developed such an efficient and low-cost catalytic system of hydrogen bond donor acetic acid (AA) in combination with KI (denoted as AA/KI) for the rapid conversion of CO2 and propylene oxide (PO). The optimal reaction condition for AA/KI catalyzing the coupling of CO2 and PO is screened by trial and error. Atime-dependent PO conversion study showed that the AA/KI catalytic system displays quite high activity to completely convert PO within a short time of 15 min under optimized conditions (0.9 MPa CO2 and 90 °C) for the best case. Moreover, AA/KI is also active for the coupling of other epoxides with CO2, and the reaction efficiency is significantly influenced by the electronic and steric effects of the epoxide substrates. In addition, the plausible mechanism was deduced. Herein, we provide an efficient and relatively mild route to catalyze the coupling of CO2 and epoxide within a short time using a non-toxic, cheap and facile catalyst.

The coupling of CO2 and epoxides is a promising way to reduce atmospheric carbon by converting it into value-added cyclic carbonate. Pursuing efficient catalysts is highly attractive for the title reaction. Herein, we developed simple and inexpensive catalyst systems of aliphatic carboxylic acids as the hydrogen-bond donor (HBD) and quaternary ammonium halides as the nucleophile to catalyze the CO2-epoxide coupling reaction with high efficiency and selectivity under mild conditions (80 °C and 4 bar CO2). The high activity of this catalyst system is retained even under ambient conditions. The effects of the acidity and steric hindrance of acids on the catalysis of CO2-epoxide coupling were systematically investigated. Lastly, the reaction mechanism was deduced and its rationality was further reinforced by exploring the interaction between a representative system AA/TBAB (acetic acid/tetrabutylammonium bromide) and propylene oxide (PO). The study of aliphatic carboxylic acids/quaternary ammonium halides provides a new way to design catalyst systems for the title reaction.

Due to its key roles in regulating the occurrence and development of cancer, protein histidine phosphorylation has been increasingly recognized as an important form of post-translational modificati...

The sulfonated covalent organic frameworks (COF@SO3H) have been synthesized by a simple one-step solvothermal reaction and used to adsorb Cd2+, Co2+, and Cr3+ metal ions from aqueous solution. The structure, composition and stability of as-prepared material were confirmed by FT-IR, PXRD, BET and TGA, and a fiber bundle-like COF@SO3H could be observed in the SEM and TEM images. The adsorption behaviors of Cd2+, Co2+, and Cr3+ onto COF@SO3H were studied through batch adsorption experiments, and the obtained data were analyzed using various models. The adsorption process of the three ions can be better described by the Langmuir isotherm and the pseudo-second-order kinetics than other models tested, and the maximum adsorption capacities for Cd2+, Co2+ and Cr3+ at 298 K are 81.97, 77.52, and 105.26 mg g−1, respectively. The thermodynamic parameters indicate that the adsorption of Cd2+ onto COF@SO3H is spontaneous, which is more favorable than Co2+ and Cr3+. Moreover, the adsorbed metal ions can be easily eluted by nitric acid or EDTA solution, and the COF@SO3H can be reused for more than 5 adsorption-elution cycles without obvious collapsing in structure and reducing in adsorption capacity. All the results suggested that the COF@SO3H could be used to the adsorption and removal of heavy metal ions from wastewater.

Objective Rho GTPase-activating protein 4 (ARHGAP4) is a GTPase-activating protein for the small GTPases of the Rho family that is involved in tumorigenesis. We recently reported that ARHGAP4 can mediate Warburg effect and malignant phenotype of pancreatic cancer. However, the regulation of ARHGAP4 remains unclear. Methods ARHGAP4 and miR-939-5p expressions in pancreatic cancer tissues and cell lines were measured by real-time PCR or Western blotting. Pancreatic cancer cells were transfected with miR-939-5p inhibitor, miR-939-5p mimic and/or lentivirus expressing ARHGAP4, and the cell viability, invasion and migration were measured by CCK-8 and Transwell assay, respectively. The suppression of ARHGAP4 expression by miR-939-5p was revealed by luciferase reporter assay, real-time PCR or Western blotting. Results ARHGAP4 expression was decreased, while miR-939-5p was increased in pancreatic cancer tissues compared with adjacent-normal pancreatic tissues. Higher miR-939-5p expression was correlated with advanced pathological stages and poor prognosis of pancreatic cancer patients. miR-939-5p directly targeted ARHGAP4. Either miR-939-5p down-regulation or ARHGAP4 overexpression inhibited viability, invasion and migration of pancreatic cancer cells. However, ARHGAP4 overexpression markedly inhibited the increased viability, migration, and invasion induced by miR-939-5p up-regulation in pancreatic cancer cells. Conclusion These observations suggested that miR-939-5p regulates the malignant phenotype of pancreatic cancer cells by targeting ARHGAP4, establishing miR-939-5p as a novel regulator of ARHGAP4 with a critical role in tumorigenesis in pancreatic cancer.

CO2 emissions reduction is one of the major concerns of human beings. The cycloaddition of CO2 and an epoxide to form a cyclic carbonate is a promising reaction for reducing atmospheric CO2 while also producing valuable industrial chemicals. In this work, we developed a series of Ni-pyrazolate-based metal–organic framework (MOF) catalysts, Nibdp-X (X = H and NO2) and Ni3btp2, to catalyze this reaction under solvent-free conditions. Herein, bdp and btp are 1,4-(4-bispyrazolyl)benzene and 1,3,5-tris(1H-pyrazol-4-yl)benzene, respectively. The unsaturated metal centers (or Lewis acid sites) in the MOFs play a key role in the cycloaddition of CO2 and epoxide. The catalytic performance of the catalysts is significantly influenced by the density and accessibility of Lewis acid sites. Moreover, the recyclability of the MOF catalysts was studied as well.

It is prerequisite to efficient extraction of phosphopeptides in bottom-up strategy for protein phosphorylation research. A kind of Ti

Zinc–air batteries (ZAB), especially those assembled on flexible substrates, have attracted great research attention in electronics and wearable electronics. However, the air–cathode reaction–oxygen reduction reaction (ORR) has limited the development of ZAB technology. In this study, a hollow carbon catalyst, NOC-1000-1, was prepared by pyrolysis of a mixture of a N-enriched Zn/bispyrozolate-based metal–organic framework and urea to replace the labile Pt-based catalysts for ORR. The employment of sacrifical urea eliminated the requirement for complicated post-treatment compared to the template method. Combined with self-activation (Zn evaporation), the obtained carbon showed a micro- and mesopore-dominant hierarchical structure coexisting with some macropores. Moreover, the doped N and O species were also tailored in a preferable configuration for ORR by simply screening the pyrolysis conditions. Under the synergistic effect of the preferable N and O configurations and pore structure, the derived carbon catalyst displayed superior ORR activity of 0.977 V onset potential and 0.867 V half-wave potential; these values are slightly better than those of the 20% Pt/C benchmark catalyst (0.985 and 0.861 V, respectively). Flexible solid-state ZABs were further assembled by employing the derived carbon catalyst as an air-cathode, and they exhibited a higher peak power density of 100.92 mW cm−2 than a 20% Pt/C—RuO2 battery as well as previously reported similar batteries and very high stability for up to 30 h. The flexible solid-state ZABs could drive a red light-emitting diode and run a 130-type motor for hours, which indicates their promising applications in real-world technologies.

A kind of zwitterionic microsphere was prepared via one-step inverse suspension polymerization employing 3-[N,N-dimethyl-[2-(2-methylpropyl-2-enyloxy) ethyl] ammonium] propane-1-sulfonate (MSA) and N,N-methylene bisacrylamide (BIS) as the precursors. The preparation conditions were carefully investigated and optimized by regulating the content of total monomers, ratio of MSA to BIS, ratio of water to oil, and content of stabilizer. The properties of microspheres were characterized by helium ion microscopy (HIM), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), N2 adsorption/desorption measurement, and water contact angle measurement. The particle size of resulting polydisperse microspheres ranged from 15–25 μm, exhibiting high specific surface area of 138 m2 g−1. Owing to great hydrophilicity, the resulting zwitterionic microspheres could be directly used as hydrophilic interaction chromatography (HILIC) sorbent to enrich glycopeptides from biosamples without any chemical modification. A total of 19 N-glycopeptides was enriched from 10 μg of IgG digest. Besides, up to 383 N-glycopeptides and 224 N-glycosylation sites were unambiguously identified from 2 μL of human serum digest by cLC-MS/MS after enrichment with zwitterionic microspheres, indicating their great enrichment performance to N-glycopeptides. The approach of preparing hydrophilic zwitterionic microspheres contains only one synthesis reaction and is suitable for large-scale preparation.

With the unique advantages in structure and property, covalent organic frameworks have been widely employed for separation and enrichment. In this work, the thiosemicarbazide-linked covalent organic framework (TpTc) was prepared by using 1,3,5-triformylphloroglucinol and non-rigid thiosemicarbazide as building blocks for the first time. The as-prepared TpTc COF was fully characterized, presenting an agaric-like structure, large specific surface area (63.5 m2 g-1), uniform pore size distribution (1.36 nm), inherent porosity and ordered crystallinity. The potential of TpTc as adsorbent for metal ions capture was investigated by static batch adsorption experiment using the one-factor procedure. The maximum adsorption capacities of 73.50, 56.53 and 94.13 mg g-1 were obtained for Cu (II), Pb (II) and Cd (II) at natural pH, respectively. The anchoring of three metal ions onto TpTc is a multi-layer sorption involving chemical adsorption, and obeys the Freundlich and pseudo-second-order model. According to XPS analysis, the adsorption mechanism may be attributed to the coordination and electrostatic interaction between metal ions and N, O and S atoms on TpTc COF. This work not only provides a candidate for the application of COFs in metal ions capture, but also a reference for exploring functional design of COFs .

A series of Ru-based catalysts have been developed for the hydrogen evolution reaction (HER) by the facile impregnation of copious and eco-friendly bacterial cellulose (BC) with Ru(bpy)3 Cl2 (bpy = 2,2'-bipyridine) followed by pyrolysis. After the oxidation and molecular recomposition processes that occur within the BC precursors during pyrolysis, sub-2 nm Ru nanoparticles (NPs) and atomic Ru species confined within surface-oxidized N-doped carbon nanofibers (CNFs) can be observed in the derived catalysts. The surface oxidation of CNFs leads the derived catalysts with super hydrophilicity and water-absorbing capacity, and also provides dimensional confinement for the nanoscaled and atomic Ru species. With these added structural advantages and the component synergy, the derived catalysts show superior HER activities, for which the overpotentials are as low as 19.6 mV (1 m KOH) and 55.0 mV (0.5 m H2 SO4 ) for the most active case at the current density of 10 mA cm-2 . Moreover, superior HER activity can be also achieved for the catalysts derived with a wide range of Ru loadings. Finally, the influence of Ru NP size on HER activity is investigated by density functional theory simulations. This method provides a reliable protocol for preparing highly active HER catalysts for scale-up applications.

β-catenin is a subunit of the cadherin protein complex and acts as an intracellular signal transducer in the Wnt signaling pathway that mediates multiple cellular processes, such as cell migration and invasion. HDAC2 (histone deacetylase 2), a deacetylase that maintains histone H3 in a deacetylated state in the promoter region of Wnt-targeted genes where β-catenin is bound, negatively regulating β-catenin activation. However, the regulation of HDAC2/β-catenin pathway remains unclear. Here, we report ARHGAP4 as a new regulator of the β-catenin pathway that regulates cell invasion and migration of pancreatic cancer as well as the downstream effector MMP2 and MMP9 expression in vitro. Mechanistically, ARHGAP4 interacts with and ubiquitinates HDAC2, which in turn inhibits β-catenin activation. Furthermore, treatment of CAY10683, an HDAC2 inhibitor, and XAV939, a Wnt/β-catenin pathway inhibitor, attenuated the effects of ARHGAP4 silencing on pancreatic cancer cells. Overall, our findings establish ARHGAP4 as a novel regulator of HDAC2/β-catenin pathway with a critical role in tumorigenesis.

Millions of tons of used cigarette filters (UCF) are worldwide discarded in the environment as toxic waste. This study provides a new application of UCF for energy storage in order to contribute to solution to environmental concerns by UCF. We have developed a facile method to fabricate nitrogen-doped hierarchical porous carbons by a combination of UCF and polypyrrole (PPy). The carbonization and activation of the as-obtained composite by KOH afforded the carbon material of very high surface area (3420 m2/g) with micro-, meso-, and macroporous structures. The nitrogen content measured by X-ray photoelectron spectroscopy was 2.34%, which is derived from PPy. The formed carbon showed large specific capacitance of 263 F/g at 1 A/g and good capacitance retention of 90% even after 5000 cycles at the current density of 5 A/ g. These excellent data are owing to the 3D hierarchical porous structure and nitrogen-doped functionality of the present carbon and UCF is regarded as a potential candidate of a carbon precursor for high-performance supercapacitors. Furthermore, this study affords a new way to recycle UCF with valuable applications, contributing to reduction of environmental pollution by UCF.

In this work, we report for the first time the application of ultrasmall Pt nanoclusters (Pt NCs) as a fluorescence-lifetime-based pH sensor. The fluorescence properties of our prepared Pt NCs show strong pH dependence, due to the change of the surface states of Pt NCs under alkaline/acidic conditions. Interestingly, both the fluorescence intensity and the fluorescence lifetime of Pt NCs exhibit a good linear relationship in the physiologically relevant pH range of 6.02-7.54. Our Pt NC-based pH sensor possesses many important features as an attractive sensor, including high anti-jamming capability, excellent stability and good reversibility. Moreover, the use of fluorescence lifetime as the optical readout signal rather than the intensity makes the present pH sensor more reliable in practical applications because the fluorescence lifetime is invariant to the probe concentration or changes in excitation conditions. Application of the Pt NC-based system for pH detection in real water samples and simulated intracellular environment samples has also been successfully demonstrated.

In this study, we found that PdPt bimetallic alloy nanowires (Pd/Pt NWs) exhibited excellent oxidase-like activity in acidic media. Their oxidase-like activity could be readily tailored by a well-defined Pd/Pt ratio, while the nanowires with Pd/Pt ratio of 1 : 3 (defined as Pd/Pt-1 : 3 NWs) proved to exhibit the most efficient catalytic oxidation activity. By using their excellent oxidase-like activity, we developed a simple colorimetric assay to detect the activity of acid phosphatase (ACP) based on its catalytic hydrolysate, ascorbic acid (AA), which effectively inhibited the action of the Pd/Pt-1 : 3 NW-mediated TMB-oxidized chromogenic reaction. Good linearity between the absorbance change and activity of ACP was obtained in the range of 0.17–2.67 U L−1, with the limit of detection as low as 0.06 U L−1. Moreover, the proposed method was also adopted to determine the ACP activity in mimicking physiological sample solutions with satisfactory results, illustrating its great potential for biological analysis.