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A heterostructured Co-based electrocatalyst is successfully synthesized using bifunctional ligand Co metal–organic frameworks as precursors. The bifunctional ligands provide enough N and O atoms that can simultaneously convert Co ions into CoN x moieties, Co nanoparticles and Co oxides via one-step pyrolysis. The obtained electrocatalysts with heterostructured CoO x /Co nanoparticles encapsulated by porous conductive carbon rich in CoN x active sites deliver remarkable oxygen reduction reaction and oxygen evolution reaction activities. With the synergistic effects among these multifunctional components, a rechargeable zinc–air battery built with this electrocatalyst exhibits a high-power density and long-lasting rechargeability. [Display omitted] Rational construction of efficient and robust bifunctional oxygen electrocatalysts is key but challenging for the widespread application of rechargeable zinc-air batteries (ZABs). Herein, bifunctional ligand Co metal–organic frameworks were first explored to fabricate a hybrid of heterostructured CoO x /Co nanoparticles anchored on a carbon substrate rich in CoN x sites (CoO x /Co@Co N C) via a one-step pyrolysis method. Such a unique heterostructure provides abundant CoN x and CoO x /Co active sites to drive oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), respectively. Besides, their positive synergies facilitate electron transfer and optimize charge/mass transportation. Consequently, the obtained CoO x /Co@Co N C exhibits a superior ORR activity with a higher half-wave potential of 0.88 V than Pt/C (0.83 V vs. RHE), and a comparable OER performance with an overpotential of 346 mV at 10 mA cm−2 to the commercial RuO 2. The assembled ZAB using CoO x /Co@Co N C as a cathode catalyst displays a maximum power density of 168.4 mW cm−2, and excellent charge–discharge cyclability over 250 h at 5 mA cm−2. This work highlights the great potential of heterostructures in oxygen electrocatalysis and provides a new pathway for designing efficient bifunctional oxygen catalysts toward rechargeable ZABs. [ABSTRACT FROM AUTHOR]

Meat adulteration has become one of the most concerning issues in the global food industry, affecting economic investment, public health and so on. In this study, a real-time fluorescent loop-mediated isothermal amplification (LAMP)-microfluidic assay was developed to simultaneously detect pork, beef, sheep and duck in foodstuffs using species-specific primers targeting the mitochondrial cytochrome b gene and cytochrome c oxidase subunit gene. Various primers were precoated in different reaction chambers of the real-time fluorescent LAMP-microfluidic chip, and the entire amplification was completed within 30 min. The real-time fluorescent LAMP-microfluidic assay exhibited good specificity and high sensitivity, with the limit of detection reaching 0.1% (w/w) in simulated adulterated samples, satisfying authentication requirements. The accuracy of this novel method was validated using 33 commercial samples and was comparable with that of the typical real-time qPCR assay. In summary, the real-time fluorescent LAMP-microfluidic assay can simultaneously detect pork, beef, sheep and duck in commercial products to verify the label certification of meat and prevent food adulteration. • A digital microfluidic chip based real-time fluorescent multiplex LAMP assay to identify meat. • The real-time fluorescent LAMP-microfluidic assay shows the limit of detection reaching 0.1% (w/w). • No cross-reactivity was detected in 14 different species using this assay. [ABSTRACT FROM AUTHOR]

Background and aims It is commonly believed that diabetes is an important contributor to heart failure (HF) development. However, the detail effect of diabetogenesis on HF is controversy: both beneficial and harmful roles were reported. In the present study, we aim to explore the unambiguous action of diabetes on chronic HF progression and the underlying mechanism. Methods Diabetes and myocardial infarction (MI) were induced by streptozotocin (STZ) injection and left-sided thoracotomy and left anterior descending coronary artery (LAD) ligation, respectively. Pyridoxamine was used as the antagonist of advanced glycation end products (AGEs). Adult male SD rats were assigned to 5 groups: Sham; MI; Diabetes (D); Diabetes + MI (DMI) and DMI + pyridoxamine (DMI + P). Animals were sacrificed at the end of 12 weeks. The comparison of LV myocardium was made between border zone from MI or DMI animals and control LV tissues from sham-operated animals. Cardiomyocytes and dendritic cells were prepared from the Sprague–Dawley rats and cocultured in the presence or absence of AGEs. Results DMI group showed highest level of AGEs and inflammatory markers, which were significantly reduced in the presence of pyridoxamine. In vitro experiment disclosed AGEs could stimulate DCs differentiation and promote cytokines production, finally upregulated hypertrophy-related genes expression in cardiocytes. Intervention DCs differentiation was sufficient to improve cardiocytes morphology. Conclusion Our results clearly demonstrate that diabetes would promote chronic HF progression at least in part through stimulating DCs differentiation and series downstream inflammatory responses induced by AGEs. [ABSTRACT FROM AUTHOR]

In this work, N -alkylated poly (4-vinylpyridine) (NPVP), a cationic polymer, was firstly applied for the surface modification of Fe 3 O 4 nanoparticles. Then the modified Fe 3 O 4 nanoparticles (Fe 3 O 4 @NPVP NPs) combined with graphene oxide (GO) through simple electrostatic binding. Subsequently, deposited Ag nanoparticles (Ag NPs) procedure was carried out to form the multiple antibacterial nanocomposites (GO-Fe 3 O 4 @NPVP-Ag). The synthesized nanostructures were well characterized by Transmission Electron Microscope (TEM), X-ray powder diffraction (XRD), Fourier-transform infrared (FT-IR) and Raman spectroscopy. The zeta potential measurement showed that the novel antibacterial nanocomposites exhibited a capacity of reversing its surface charge from negative (physiological pH) to positive (acidic condition). Furthermore, the incorporation of magnetic Fe 3 O 4 NPs into the nanosystems facilitates the cyclic utilization of GO-Fe 3 O 4 @NPVP-Ag by magnetic separation. The antibacterial properties of GO-Fe 3 O 4 @NPVP-Ag nanocomposites were evaluated with Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus . Moreover, the cytotoxicity of GO-Fe 3 O 4 @NPVP-Ag nanocomposites was studied using NIH-3T3 cells. The results showed that the GO-Fe 3 O 4 @NPVP-Ag nanocomposites exhibited excellent antibacterial properties and low cytotoxicity, thus confirming its application as a promising rapid bactericide in various antibacterial fields. [ABSTRACT FROM AUTHOR]

To address the issues of long drying time and high equipment costs present in freeze drying and freeze drying-microwave vacuum combined drying techniques, as well as to obtain higher-quality dried products, multiphase microwave drying (MMD) has been proposed. This study investigated the effects of MMD at different transition point moisture content levels (0.36, 0.59, and 0.79 g/g d.b.) on the microstructure and texture of dried Chinese yam. Using freeze drying (FD), microwave freeze drying (MFD), and microwave vacuum drying (MVD) as controls, X-ray micro-computed tomography (micro-CT) visualized and quantified Chinese yam's structure across drying methods. The results indicated that as the transition point moisture content increased, the porosity and connected pore area and volume decreased, while non-connected pore area and volume increased. Chinese yam samples obtained from MMD scheme I (transition point moisture content of 0.36 g/g d.b.) exhibited a uniform and porous structure with a high total porosity (48.19 ± 0.32%), similar in hardness and shrinkage to freeze-dried yams, preserving microstructural integrity. MMD reduced drying time and maintained the quality of dried Chinese yam compared to FD, MVD, and MFD, highlighting its potential as a cost-effective method for producing premium dried Chinese yam products. • Multiphase microwave drying was proposed. • Micro-CT was used to study the internal structure of Chinese yam. • The Chinese yam in scheme I exhibited a uniform and porous structure with a high total porosity. • Multiphase microwave drying can produce high quality dried products of Chinese yam. [ABSTRACT FROM AUTHOR]

This study characterized the nanoparticles and the binding mechanism between pH-shifted soy β-conglycinin (β-CG) and hesperetin (Ht)/hesperidin (Hd). Different structural characteristics and concentrations of Ht/Hd were found to affect the encapsulation efficiency, loading amount, and particle size of pH-shifted β-CG‒Ht/Hd nanoparticles. This was the result of two glycosyl substituents (7-position of the C-ring) in the presence of Hd containing six hydroxyl groups interacting with the polar groups of proteins to form hydrogen bonds, which facilitated the formation of nanocomplexes. Besides, the exposed hydrophobic groups in the β-CG proteins resulting from pH shift treatment developed hydrophobic interactions with the benzene ring or glucoside in the flavonoids. Moreover, Ht/Hd strongly quenched the fluorescence of pH-shifted β-CG in static mode. After binding with flavonoids, the tertiary and secondary structures of pH-shifted β-CG were significantly changed. The finding presented in this study provided evidence of the binding mechanism of soy proteins and different structural flavonoids and will aid in the design of soy protein/flavonoid enriched-food. • Binding mechanisms of Ht/Hd to pH-shifted β-CG were investigated. • Different structures and concentrations of Ht and Hd affected the binding. • Ht/Hd quenched the intrinsic fluorescence of pH-shifted β-CG in a static mode. • Hydrophobic interactions and hydrogen bonds mainly drove the binding. • The binding affected the tertiary and secondary structures of pH-shifted β-CG. [ABSTRACT FROM AUTHOR]

Changes in viscoelastic properties and physical qualities including rehydration ratio (RR), volume ratio (Vr), porosity and texture of Chinese yams during multiphase microwave drying (MMD) were studied and the intrinsic relationship between them was analyzed. Results showed that RR, Vr and porosity rose and then fell with drying time during MMD, with the endpoint of sublimation drying being the turning point. Scheme III with the highest microwave power (0.2 W/g) in sublimation drying resulted in the lowest RR, Vr and porosity but the highest hardness. The Maxwell model was well fitted to describe the viscoelastic behaviors of yams (R 2 > 0.99). Enhanced stress relaxation behavior during sublimation drying was observed. In contrast, a decrease in stress decay but an increase in residual elasticity were found when MMD switched from sublimation drying to evaporation drying. Pearson's correlation analysis showed that relaxation modulus was significantly negatively correlated with RR (r = −0.981, p < 0.01) and porosity (r = −0.961), while positively correlated with hardness (r = 0.94, p < 0.05) and the brittleness (r = 0.96, p < 0.01). Principal component regression models between the viscoelastic indexes and physical features with high R 2 (>0.9) values could explain their relationships well. These findings have implications for the production of high-quality products through controlling drying processes. • Three loading schemes for multiphase microwave drying of Chinese yam were studied. • Frozen state samples were predominantly elastomeric. • Evolution in physical properties turned at the end of sublimation drying. • Pore structure and moisture phase state of the sample affected relaxation behaviors. [ABSTRACT FROM AUTHOR]

Hypoxia-induced inhibition of apoptosis in pulmonary artery endothelial cells (PAECs) has an important role in pulmonary arterial remodeling leading to aggravated hypoxic pulmonary arterial hypertension. However, the mechanisms involved in the hypoxia-induced inhibition of PAEC apoptosis have not been elucidated. e -selectin and biliverdin reductase (BVR) have been reported to contribute to the cascade of apoptosis in several cell lines but not in PAECs. In the present study, we show that the expression of e -selectin and BVR was both up-regulated by hypoxia in PAECs. Moreover, hypoxia attenuated the decreased cell survival and apoptotic protein expression, and increased DNA fragmentation induced by serum deprivation in the PAECs, which was mediated by the e -selectin/BVR pathway. In addition, by examining the mitochondrial membrane potential and mitochondrial membrane proteins (Bcl-2 and BAX), we show that the mitochondrial-dependent apoptosis pathway was necessary for the e -selectin/BVR pathway inducing the anti-apoptotic effect of hypoxia in PAECs. Taken all together, our data show that the e -selectin/BVR pathway participates in the inhibitory process of hypoxia in PAEC apoptosis which is mediated by the mitochondrial-dependent apoptosis pathway. [ABSTRACT FROM AUTHOR]

As a by-product of juice industry, blueberry pomace is still a rich source of phytochemicals with potential benefits for human health. However, studies about blueberry pomace utilization are insufficient. In this study, the blueberry pomace was fermented by the probiotic Lactobacillus casei and the potential function of fermented blueberry pomace (FBP) was evaluated, including the antioxidant activity, the regulation of fecal microbiota and the production of short chain fatty acids (SCFA). The results showed that FBP obtained improved antioxidant activity which was positively correlated with the content of polyphenols. The microbiota community structure was improved by FBP through inhibiting Escherichia coli , Enterococcus and the ratio of Firmicutes and Bacteroidetes as well as improving Bifidobacterium , Ruminococcus , Lactobacillus , Akkermansia and butyrate-producing bacteria. The SCFA, especially acetic, butyric and lactic acids, were remarkably increased because of FBP-supplementation. Further, UPLC-MS analysis showed that forty-six phenolic compounds were detected in FBP while only thirty-eight in non-fermented blueberry pomace (NFBP), explaining the speculation of this study that the phytochemicals in FBP might increase the gut-improving function. This study suggested that the Lactobacillus casei -fermentation was useful for utilizing blueberry pomace as a potential candidate for functional foods. • The antioxidative properties of fermented blueberry pomace (FBP) were enhanced. • Antioxidant properties were positively correlated with phenolic concentrations. • FBP improved the microbiota community structure. • FBP increased the production of short chain fatty acids. • The fermentation expanded the utilization of berry pomace in beverage industry. [ABSTRACT FROM AUTHOR]