Decarbonization has become an urgent affair to restrain global warming. CO2 hydrogenation coupled with H2 derived from water electrolysis is considered a promising route to mitigate the negative ...impact of carbon emission and also promote the application of hydrogen. It is of great significance to develop catalysts with excellent performance and large-scale implementation. In the past decades, metal–organic frameworks (MOFs) have been widely involved in the rational design of catalysts for CO2 hydrogenation due to their high surface areas, tunable porosities, well-ordered pore structures, and diversities in metals and functional groups. Confinement effects in MOFs or MOF-derived materials have been reported to promote the stability of CO2 hydrogenation catalysts, such as molecular complexes of immobilization effect, active sites in size effect, stabilization in the encapsulation effect, and electron transfer and interfacial catalysis in the synergistic effect. This review attempts to summarize the progress of MOF-based CO2 hydrogenation catalysts up to now, and demonstrate the synthetic strategies, unique features, and enhancement mechanisms compared with traditionally supported catalysts. Great emphasis will be placed on various confinement effects in CO2 hydrogenation. The challenges and opportunities in precise design, synthesis, and applications of MOF-confined catalysis for CO2 hydrogenation are also summarized.
Our previous study has proved that the three polysaccharide fractions from L. japonica (LP-A4, LP-A6, and LP-A8) had significantly different structure characterization. Herein, we conducted in vitro ...simulated digestion and fermentation to study the digestive mechanism of LP-As. The results of gastrointestinal digestion indicated that LP-A6 and LP-A8 would be easier to trap the enzyme molecules for their denser interconnected macromolecule network compared with LP-A4. Fermentation of LP-As by human gut microbiota, especially for LP-A8, generated a large amount of short-chain fatty acids (SCFAs), which could upregulate the abundance of Firmicutes (Lachnoclostridium and Eubacterium). The high content of sulfate and highly branched sugar residue of LP-A8 might help it be easily used by Firmicutes in gut microbiota of hyperlipidemic patients. Functional analysis revealed that the increased metabolic activities of glycerophospholipid metabolism, ether lipid metabolism, and fatty acid metabolism induced by LP-A8 treatment were closely associated with metabolic syndromes and hyperlipidemia.
lThe performance of the TPCT using different nanofluids are studied experimentally.lThe effects of various operating conditions on thermal performance are studied.lThe results manifest that the ...hybrid nanofluid intensified the heat transfer.lThermal efficiency of hybrid nanofluid increased by 10.6%, compared with the DW.
The heat transfer performance of single and hybrid nanofluids in a two-phase closed thermosyphon (TPCT) was experimentally studied and compared with deionized water (DW). Al2O3 and TiO2 nanoparticles with a volume concentration of 0.2% were added to the DW in two steps to prepare stable nanofluid suspensions (Al2O3H2O, TiO2H2O, 75% Al2O3 + 25% TiO2H2O, 50% Al2O3 + 50% TiO2H2O, and 25% Al2O3 + 75% TiO2H2O). The TPCT was made of a carbon steel tube of length 500 mm, outer diameter 20 mm, and wall thickness 2 mm. In this study, through an orthogonal experiment, the five types of nanofluids were analyzed to obtain the single and hybrid nanofluids with the best heat transfer performance. These were compared with DW under various conditions of the heating power, which were varied from 200 to 400 W in equal steps of 50 W, the liquid filling ratio (30%, 50%, 70%), and the cooling water flow rate (0.4, 0.48, 0.56 L/min). The results showed that when the hybrid nanofluid 25% Al2O3 + 75% TiO2H2O and the single nanofluid TiO2H2O were used instead of DW, the best heat transfer performance was displayed. For the heating input of 400 W, filling ratio of 50%, and cooling water flow of 0.4 L/min, the thermal resistance of the TPCT was reduced by 26.8% and 22.8%, the equivalent heat transfer coefficient increased by 25.78% and 21.62%, the thermal efficiency was increased by 10.6% and 9.2%, respectively.
The flexible grasping, force sensing, and in-hand manipulating abilities of the gripper are theoretically significant and practically valuable to solve. However, it is still difficult for most ...existing grippers to realize these three functions simultaneously. This article proposed a novel humanoid finger-functional parallel gripper with two actuators based on overlapping parallelogram mechanisms and the series elastic actuator (SEA). Based on the in-hand manipulation principle for the ordinary contour object (OCO), an in-hand manipulation algorithm for grasping force and position decoupling was designed. Then, to adjust the posture and position of objects within parallel fingers, the rolling and sliding conditions of objects based on the molecular-mechanical friction theory were analyzed. Combined with the proposed in-hand manipulating conditions and algorithm, the PG2 gripper can control the grasping force and manipulate the OCO in-hand controllably. Evaluation experimental results showed that the force-position control of the PG2 gripper was decoupled stably and the gripper had high accuracy in controlling force and position. Finally, the physical features perception experiments and the in-hand manipulating experiment were carried out to demonstrate the utility of the proposed manipulating methods and algorithm, and in-hand manipulating and grasping force sensing abilities of the gripper. The possible applications of this gripper include tasks that need accurate force-position control or manipulating and sensing in-hand remotely.
Dexmedetomidine (DEX) has multiple biological effects. Here, we investigated the neuroprotective role and molecular mechanism of DEX against lipopolysaccharide (LPS)-induced hippocampal neuronal ...apoptosis. Sprague Dawley rats were intraperitoneally injected with LPS (10 mg/kg) and/or DEX (30 µg/kg). We found that DEX improved LPS-induced alterations of hippocampal microstructure (necrosis and neuronal loss in the CA1 and CA3 regions) and ultrastructure (mitochondrial damage). DEX also attenuated LPS-induced inflammation and hippocampal apoptosis by inhibiting the increase of interleukin-1β, interleukin-6, interleukin-18, and tumor necrosis factor-α levels and downregulating the expression of mitochondrial apoptosis pathway-related proteins. Moreover, DEX prevented the LPS-induced activation of the c-Myc/chloride intracellular channel 4 (CLIC4) pathway. DEX inhibited the p38 MAPK pathway, but not JNK and ERK. To further clarify whether DEX alleviated LPS-induced neuronal apoptosis through the p38 MAPK/c-Myc/CLIC4 pathway, we treated PC12 cells with p38 MAPK inhibitor SB203582 (10 µM). DEX had the same effect as SB203582 in reducing the protein and mRNA expression of c-Myc and CLIC4. Furthermore, DEX and SB203582 diminished LPS-induced apoptosis, indicated by decreased Bax and Tom20 fluorescent double-stained cells, reduced annexin V-FITC/PI apoptosis rate, and reduced protein expression levels of Bax, cytochrome C, cleaved caspase-9, and cleaved caspase-3. Taken together, the findings indicate that DEX attenuates LPS-induced hippocampal neuronal apoptosis by regulating the p38 MAPK/c-Myc/CLIC4 signaling pathway. These findings provide new insights into the mechanism of Alzheimer’s disease and depression and may help aid in drug development for these diseases.
•Pinobanksin, galangin and pinocembrin showed excellent XOD inhibitory activities.•Five studied flavonoids could interact with XOD at more than one binding sites.•Inhibitory mechanism varied with ...substrate's or inhibitor's type and concentration.
Xanthine oxidase (XOD) inhibitory activities of five dietary flavonoids pinobanksin, galangin, pinocembrin, pinocembrin-7-O-β-d-glucopyranoside and glabranin were evaluated. Enzyme kinetic studies and molecular docking simulation were conducted to investigate the mechanisms underlying the inhibitory activities. The results showed that these flavonoids exhibited excellent inhibitory activities (which were ranked in the order of pinobanksin > galangin > pinocembrin > pinocembrin-7-O-β-d-glucopyranoside > glabranin). Competitive inhibition and a mixed-type of competitive–noncompetitive inhibition were observed. The mode of inhibition was dependent on the type and concentration of the substrate and inhibitor. Fluorescence quenching data suggested that these flavonoids could interact with XOD at more than one binding site. The docking simulation revealed that galangin and pinobanksin could enter into the active site of XOD and form hydrogen bonding with amino acid residues (such as Ser-876, Asn-768, Glu-1261 and Thr-1010) and sandwiching aromatic interactions (π–π interactions) around the active site of XOD.
•Alcalase and Flavorzyme hydrolysed peanut flour or its protein isolate efficiently.•Flavorzyme hydrolysis residue was used to study the hydrolysis discrepancy.•Peanut protein isolate was hydrolysed ...less effectively than defatted peanut flour.•Peptide aggregation via non-covalent bonding reduced the hydrolysis efficiency.
Both defatted peanut flour (DPF) and peanut protein isolate (PPI) are widely used to prepare peanut protein hydrolysates. To compare their enzymatic hydrolysis efficiencies, DPF and PPI were hydrolysed by Alcalase, Neutrase, Papain, Protamex and Flavorzyme. Alcalase and Flavorzyme were found to be the most efficient proteases to hydrolyse both DPF and PPI. The efficiency was comparable to each other when using Alcalase, while PPI was hydrolysed less efficiently than DPF when using Flavorzyme. Analysis of changes in the protein solubility, subunit and conformation, and amino acid composition of DPF, PPI and their Flavorzyme hydrolysis residues indicated that the PPI preparation process had minimal effect on it, but peptide aggregation via non-covalent bonding (including hydrophobic interactions and hydrogen bonds) during hydrolysis and/or thermal treatment after hydrolysis were likely responsible for the reduced hydrolysis efficiency of PPI by Flavorzyme.
Long-time hypoxia induced cardiomyocyte apoptosis is an important mechanism of myocardial ischemia (MI) injury. Interestingly, long noncoding RNA myocardial infarction-associated transcript (LncMIAT) ...has been involved in the regulation of MI injury; however, the underlying mechanism by which LncMIAT affects the progression of hypoxia-induced cardiomyocyte apoptosis remains unclear. In the present study, hypoxia was found to promote cardiomyocyte apoptosis through an increased expression of LncMIAT in vitro. Biological investigations and dual-luciferase gene reporter assay further revealed that LncMIAT was able to bind with miR-708-5p to upregulate the p53-mediated cell death of the cardiomyocytes. Silencing of LncMIAT or overexpression of miR-708-5p led to a significant reduction in p53-mediated cardiomyocyte apoptosis. The methylated RNA immunoprecipitation (MeRIP)-qPCR results showed that hypoxia exerted its effects on LncMIAT through AKLBH5-N6-methyladenosine (m6A) methylation and therefore hypoxia was shown to trigger HL-1 cardiomyocyte apoptosis via the m6A methylation-mediated LncMIAT/miR-708-5p/p53 axis. Silencing of AKLBH5 significantly alleviated the m6A methylation-mediated LncMIAT upregulation and p53-mediated cardiomyocyte apoptosis, while promoted miR-708-5p expression. Taken together, the present study highlighted that LncMIAT could act as a key biological target during hypoxia-induced cardiomyocyte apoptosis. In addition, it was shown that hypoxia could promote cardiomyocyte apoptosis through regulation of the m6A methylation-mediated LncMIAT/miR-708-5p/p53 signaling axis.
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•Dietary mannogluconic acid (MA) and fucogalactan sulfate (FS), with distinct structure characterization, affected differently on HFC-induced hyperlipidemia.•FS with highly branched ...sugar residue and sulfate ester groups protected effectively against HFC-induced hyperlipidemia.•FS increased the relative abundance of beneficial bacteria and the production of short-chain fatty acids (SCFAs).•FS changed the metabolites associated with bile acid biosynthesis, which might contribute to synthesizing primary bile acid from cholesterol and thus decreasing the serum TC level.
Our previous study found dietary mannogluconic acid (MA) and fucogalactan sulfate (FS) from Laminaria japonica have distinct structure characterization and potential hypolipidemic effects in vitro. Herein, we compared the benefits of MA and FS on hyperlipidemia. The result showed only FS treatment decreased body weight and serum cholesterol levels. Compared with MA, FS was more effective in mitigating hepatic fat accumulation, promoting GSH-Px activity, reducing the MDA formation, and lowering the level of TNF-α in liver. Gut microbiota and metabolism analysis revealed that FS increased the relative abundance of beneficial bacteria and boosted the level of short chain fatty acids. Particularly, taurine and 3α,7α,12α-trihydroxy-24-oxo-5-β-cholestanoyl CoA were upregulated by FS, which might attribute to the increased Oscillibacter and thus affect the enterohepatic circulation of bile acids and serum TC level. Therefore, FS with more branches and sulfate ester groups could be a good lipid-lowering dietary supplement.
Myocardial infarction (MI) remains one of the major causes of high morbidity and mortality worldwide. Danggui Buxue Decoction (DBD)—an ancient Chinese herbal decoction—has been used to prevent ...coronary heart disease, which was called “chest palsy” in ancient clinics. However, the mechanism of DBD in the treatment of MI remains unclear. The aim of this study was to explore the effect and mechanism of DBD on MI by combining network pharmacology with in vivo experiments.
First, public databases were used to identify the key active chemicals and possible targets of DBD. The MI targets were obtained from the Therapeutic Target Database, and the function of the target genes in relation to linked pathways was investigated. Subsequently, Cytoscape software was used to build a target-signaling pathway network. Finally, the efficacy of DBD therapy on MI was validated using in vivo investigations combined with molecular docking.
In traditional Chinese medicine systems pharmacology database and analysis platform (TCMSP), 27 bioactive compounds were screened from DBD. A total of 213 common targets were obtained, including 507 DBD targets and 2566 MI targets. Enrichment analysis suggests that PI3K/AKT is a potential signaling pathway for DBD-based protection. Immunofluorescence and protein blotting confirmed PI3K/AKT1, ERK2, and CASPASE-9 as the target proteins. Molecular docking analysis showed that quercetin, kaempferol, isoflavanones, isorhamnetin, hederagenin, and formononetin had high binding affinity to AKT1, ERK2, and CASPASE-9.
This study demonstrated that the therapeutic benefit of DBD on MI may be mediated via target proteins in the PI3K/AKT pathway, such as AKT1, ERK2, and CASPASE-9. Our study data can help to provide ideas and identify new treatment targets for MI.
Schematic diagram of DBD against MI based on network pharmacology and experimental identification. Display omitted
•Network pharmacology, molecular docking, and experimental verification were used for analysis.•The protective effect of DBD against MI was studied.•PI3K/Akt1 signaling pathway is involved in the therapeutic effect of DBD on MI.
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