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Developing high-efficiency and stable bifunctional electrocatalysts for water splitting remains a great challenge. Herein, NiMoO4 nanowires as sacrificial templates to synthesize Mo-doped NiFe Prussian blue analogs are employed, which can be easily phosphorized to Mo-doped Fe2xNi2(1-x)P nanotubes (Mo-FeNiP NTs). This synthesis method enables the controlled etching of NiMoO4 nanowires that results in a unique hollow nanotube architecture. As a bifunctional catalyst, the Mo-FeNiP NTs present lower overpotential and Tafel slope of 151.3 (232.6) mV at 100 mA cm-2 and 76.2 (64.7) mV dec-1 for HER (OER), respectively. Additionally, it only requires an ultralow cell voltage of 1.47 V to achieve 10 mA cm-2 for overall water splitting and can steadily operate for 200 h at 100 mA cm-2. First-principles calculations demonstrate that Mo doping can effectively adjust the electron redistribution of the Ni hollow sites to optimize the hydrogen adsorption-free energy for HER. Besides, in situ Raman characterization reveals the dissolving of doped Mo can promote a rapid surface reconstruction on Mo-FeNiP NTs to dynamically stable (Fe)Ni-oxyhydroxide layers, serving as the actual active species for OER. The work proposes a rational approach addressed by electron manipulation and surface reconstruction of bimetallic phosphides to regulate both the HER and OER activity.
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BACKGROUND: Observational studies have suggested an association between birth weight and type 2 diabetes mellitus, but the causality between them has not been established. We aimed to obtain the causal relationship between birth weight with T2DM and quantify the mediating effects of potential modifiable risk factors. METHODS: Two-step, two-sample Mendelian randomization (MR) techniques were applied using SNPs as genetic instruments for exposure and mediators. Summary data from genome-wide association studies (GWAS) for birth weight, T2DM, and a series of fatty acids traits and their ratios were leveraged. The inverse variance weighted (IVW) method was the main analysis approach. In addition, the heterogeneity test, horizontal pleiotropy test, Mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO) test, and leave-one-out analysis were carried out to assess the robustness. RESULTS: The IVW method showed that lower birth weight raised the risk of T2DM (ß: -1.113, 95% CI: -1.573 â¼ -0.652). Two-step MR identified 4 of 17 candidate mediators partially mediating the effect of lower birth weight on T2DM, including ratio of polyunsaturated fatty acids to monounsaturated fatty acids (proportion mediated: 7.9%), ratio of polyunsaturated fatty acids to total fatty acids (7.2%), ratio of omega-6 fatty acids to total fatty acids (8.1%) and ratio of linoleic acid to total fatty acids ratio (6.0%). CONCLUSIONS: Our findings supported a potentially causal effect of birth weight against T2DM with considerable mediation by modifiable risk factors. Interventions that target these factors have the potential to reduce the burden of T2DM attributable to low birth weight.
Subject(s)
Diabetes Mellitus, Type 2 , Fatty Acids , Humans , Diabetes Mellitus, Type 2/genetics , Birth Weight/genetics , Genome-Wide Association Study , Mendelian Randomization Analysis , Fatty Acids, MonounsaturatedABSTRACT
BACKGROUND: Gualou is derived from the fruit of Trichosanthes kirilowii Maxim, while Xiebai from the bulbs of Allium macrostemon Bunge. Gualou and Xiebai herb pair (2:1) is widely used in clinical practice to treat atherosclerotic cardiovascular diseases. However, the mechanism underlying its potential activity on atherosclerosis (AS) has not been fully elucidated. METHODS: The extract of Gualou-Xiebai herb pair (GXE) was prepared from Gualou (80 g) and Xiebai (40 g) by continuous refluxing with 50% ethanol for 2 h at 80°C. In vivo, ApoE-/- mice were fed a high-fat diet (HFD) for 10 weeks to induce an AS model, and then the mice were treated with GXE (3, 6, 12 g/kg) or atorvastatin (10 mg/kg) via oral gavage. Besides, RAW264.7 macrophages were stimulated by ox-LDL to establish a foam cell model in vitro. RESULTS: GXE suppressed plaque formation, regulated plasma lipids, and promoted liver lipid clearance in AS mice. In addition, 0.5, 1, and 2 mg/mL GXE significantly reduced the TC and FC levels in ox-LDL (50 µg/mL)-stimulated foam cells. GXE increased cholesterol efflux from the foam cells to ApoA-1 and HDL, and enhanced the protein expressions of ABCA1, ABCG1, and SR-BI, which were reversed by the PPARγ inhibitor. Meanwhile, GXE increased the LCAT levels, decreased the lipid levels and increased the TBA levels in the liver of AS mice. Molecular docking indicated that some compounds in GXE showed favorable binding energy with PPARγ, LCAT and CYP7A1 proteins, especially apigenin-7-O-ß-D-glucoside and quercetin. CONCLUSION: In summary, our results suggested that GXE improved lipid metabolism disorders by enhancing RCT, providing a scientific basis for the clinical use of GXE in AS treatment.
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Single-site copper-based catalysts have shown remarkable activity and selectivity for a variety of reactions. However, deactivation by sintering in high-temperature reducing environments remains a challenge and often limits their use due to irreversible structural changes to the catalyst. Here, we report zeolite-based copper catalysts in which copper oxide agglomerates formed after reaction can be repeatedly redispersed back to single sites using an oxidative treatment in air at 550 °C. Under different environments, single-site copper in Cu-Zn-Y/deAlBeta undergoes dynamic changes in structure and oxidation state that can be tuned to promote the formation of key active sites while minimizing deactivation through Cu sintering. For example, single-site Cu2+ reduces to Cu1+ after catalyst pretreatment (270 °C, 101 kPa H2) and further to Cu0 nanoparticles under reaction conditions (270-350 °C, 7 kPa EtOH, 94 kPa H2) or accelerated aging (400-450 °C, 101 kPa H2). After regeneration at 550 °C in air, agglomerated CuO was dispersed back to single sites in the presence and absence of Zn and Y, which was verified by imaging, in situ spectroscopy, and catalytic rate measurements. Ab initio molecular dynamics simulations show that solvation of CuO monomers by water facilitates their transport through the zeolite pore, and condensation of the CuO monomer with a fully protonated silanol nest entraps copper and reforms the single-site structure. The capability of silanol nests to trap and stabilize copper single sites under oxidizing conditions could extend the use of single-site copper catalysts to a wider variety of reactions and allows for a simple regeneration strategy for copper single-site catalysts.
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Pretreatment process is considered as the most important step for effective microalgae biomass refining and has gained more interest since last decades. However, the main obstacles to commercialize microalgae products are recalcitrant cell wall and lack of cost-effective, green, and sustainable pretreatment approaches. Till now, various microalgae pretreatment approaches have been applied prior to extraction steps to enhance the accessibility of solvent inside the cells. However, high energy consumption and the hazardousness of solvents are considerable problem for these pretreatment methods. In this regard, deep eutectic solvents are recognized as sustainable and green solvents possessing great potential for microalgae biomass processing due to their low toxicity, low cost, biodegradability, easy recycling, and reuse. This article provides the fundamentals of DES composition, synthesis, properties, and the current advances in the application of microalgae biomass process.
Subject(s)
Lignin , Microalgae , Deep Eutectic Solvents , Biomass , SolventsABSTRACT
BACKGROUND: Atherosclerosis (AS) is a chronic disease characterized by lipid accumulation in the aortic wall and the formation of foam cells overloaded with large lipids inclusions. Currently, Western medicine is primarily used to improve lipid metabolism disorders and reduce inflammatory reactions to delay AS progression, but these medicines come with serious side effects and drug resistance. Gualou-Xiebai (GLXB) is a renowned herb pair that has been proven effective against AS. However, the potential molecular mechanism through which GLXB exerts the anti-atherosclerotic effects of increasing lipophagy in vascular smooth muscle cells (VSMCs) remains unknown. PURPOSE: This study aims to explore the role of lipophagy and the therapeutic mechanism of GLXB in AS. METHODS: UPLC-Q-TOF-MS for the determination of the main components of GLXB-containing serum. An AS mouse model was established by feeding a high-fat diet (HFD) to ApoE-/- mice for 12 weeks. Ultrasonography monitoring was used to confirm the successful establishment of the AS model. Plaque areas and lipid deposition were evaluated using HE staining and aorta imagingafter GLXB treatment. Immunofluorescence staining and Western blotting were utilized to observe the P2RY12 and lipophagy levels in AS mice. VSMCs were stimulated with oxidized low-density lipoprotein (ox-LDL) to induce foam cell formation. The degree of lipophagy and the related molecular mechanisms were assessed after treating the VSMCs with GLXB-containing serum or si-P2RY12 transfection. The active components of GLXB-containing serum that act on P2RY12 were screened and verified by molecular docking and dual-luciferase reporter assays. RESULTS: Seventeen components of GLXB were identified in rat serum by UPLC-Q-TOF-MS. GLXB significantly reduced lipid deposition in HFD-fed ApoE-/- mice and ox-LDL-induced VSMCs. GLXB strikingly increased lipophagy levels by downregulating P2RY12, p62, and plin2, upregulating LC3â ¡ protein expression, and increasing the number of autophagosomes. Notably, the lipophagy inhibitor CQ and the P2RY12 receptor agonist ADPß abolished the GLXB-induced increase in lipophagy. Last, we confirmed that albiflorin, apigenin, luteolin, kaempferol, 7,8-dihydroxyflavone, and hesperetin from GLXB significantly inhibited P2RY12. CONCLUSION: GLXB activates lipophagy and inhibits lipid accumulation-associated VSMC-derived foam cell formation through suppressing P2RY12 activation, resulting in anti-atherosclerotic effects. The GLXB components albiflorin, apigenin, luteolin, kaempferol, 7,8-dihydroxyflavone, and hesperetin are the potential active effectors against P2RY12.
Subject(s)
Atherosclerosis , Drugs, Chinese Herbal , Foam Cells , Muscle, Smooth, Vascular , Receptors, Purinergic P2Y12 , Animals , Atherosclerosis/drug therapy , Foam Cells/drug effects , Foam Cells/metabolism , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/metabolism , Male , Mice , Drugs, Chinese Herbal/pharmacology , Receptors, Purinergic P2Y12/metabolism , Diet, High-Fat , Mice, Inbred C57BL , Myocytes, Smooth Muscle/drug effects , Myocytes, Smooth Muscle/metabolism , Rats , Disease Models, Animal , Autophagy/drug effects , Rats, Sprague-Dawley , Lipid Metabolism/drug effects , Aorta/drug effects , Lipoproteins, LDL/metabolismABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Atherosclerosis (AS) is a chronic vascular ailment characterized by inflammatory and lipid deposition in the arterial wall caused by endothelial injury. Ferroptosis is a novel type of cell death, and endothelial ferroptosis is a significant contributor to the progression of AS. Gualou-Xiebai (GLXB) is a renowned Chinese herb pair that serves a crucial function in treating AS. However, whether the underlying mechanism of GLXB plays a role in anti-atherosclerotic effects by inhibiting ferroptosis in endothelial cells has not been determined. AIM OF THE STUDY: To explore the influence of GLXB on endothelial ferroptosis and determine its underlying mechanism of action in AS. MATERIALS AND METHODS: In ApoE-/- mice, ultrasound was performed in mice fed a high-fat diet (HFD) for 12 weeks to assess the success of AS establishment. Then, ApoE-/- mice were treated with GLXB and Simvastatin (positive control) for 4 weeks. The effects of GLXB on AS pathology were assessed through aorta imaging and hematoxylin-eosin (HE) staining. To confirm the presence of ferroptosis, mitochondrial damage was observed using transmission electron microscope (TEM), along with analysis of free iron and lipid peroxidation levels. In vitro: ox-LDL-induced human vascular endothelial cells (HUVECs) injury and treated with GLXB, the ferroptosis inducer Erastin and an Nrf2 inhibitor ML385. Cell viability was evaluated using the CCK-8 assay in all groups. Flow cytometry was employed to detect lipid peroxidation and intracellular ferrous iron levels. Immunofluorescence staining microscopy verified Nrf2 nuclear translocation. Protein expression were measured by Western blot analysis. RESULTS: GLXB improved atherosclerotic aortic lesions and vascular plaques. GLXB inhibited endothelial injury in the aorta by decreasing the levels of inflammatory factors and adhesion factors, and by decreasing the shedding of endothelial cells. GLXB suppressed ferroptosis in ApoE-/- mice by attenuating mitochondrial damage in ECs, increasing the levels of glutathione (GSH) and superoxide dismutase (SOD) in aortic tissues and down-regulating the levels of levels of lipid peroxide (LPO) and malondialdehyde (MDA). Interestingly, Erastin was used to demonstrate in vitro that GLXB inhibition of ferroptosis attenuated ox-LDL-induced injuring effects on HUVECs that were reversed by Erastin. Mechanistically, GLXB activates the Nrf2 signaling pathway to inhibit ferroptosis by increasing downstream anti-ferroptosis target proteins and promoting the interaction between Nrf2 and SLC7A11. More convincingly, ML385 (Nrf2 inhibitor) reversed the anti-ferroptosis effect of GLXB. CONCLUSION: GLXB inhibits ferroptosis-mediated endothelial cell injury via activating the Nrf2 signaling pathway and further alleviates AS pathological damage.
Subject(s)
Atherosclerosis , Ferroptosis , Lipoproteins, LDL , Humans , Animals , Mice , Endothelial Cells , NF-E2-Related Factor 2/metabolism , Diet, High-Fat/adverse effects , Atherosclerosis/metabolism , Apolipoproteins E/genetics , Iron/metabolismABSTRACT
Singlet oxygen (term symbol 1Δg, hereafter 1O2), a reactive oxygen species, has recently attracted increasing interest in the field of rechargeable batteries and electrocatalysis and photocatalysis. These sustainable energy conversion and storage technologies are of vital significance to replace fossil fuels and promote carbon neutrality and finally tackle the energy crisis and climate change. Herein, the recent progresses of 1O2 for energy storage and conversion is summarized, including physical and chemical properties, formation mechanisms, detection technologies, side reactions in rechargeable batteries and corresponding inhibition strategies, and applications in electrocatalysis and photocatalysis. The formation mechanisms and inhibition strategies of 1O2 in particular aprotic lithium-oxygen (Li-O2) batteries are highlighted, and the applications of 1O2 in photocatalysis and electrocatalysis is also emphasized. Moreover, the confronting challenges and promising directions of 1O2 in energy conversion and storage systems are discussed.
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LiBH4 is one of the most promising candidates for use in all-solid-state lithium batteries. However, the main challenges of LiBH4 are the poor Li-ion conductivity at room temperature, excessive dendrite formation, and the narrow voltage window, which hamper practical application. Herein, we fabricate a flexible polymeric electronic shielding layer on the particle surfaces of LiBH4. The electronic conductivity of the primary LiBH4 is reduced by 2 orders of magnitude, to 1.15 × 10-9 S cm-1 at 25 °C, due to the high electron affinity of the electronic shielding layer; this localizes the electrons around the BH4- anions, which eliminates electronic leakage from the anionic framework and leads to a 68-fold higher critical electrical bias for dendrite growth on the particle surfaces. Contrary to the previously reported work, the shielding layer also ensures fast Li-ion conduction due to the fast-rotational dynamics of the BH4- species and the high Li-ion (carrier) concentration on the particle surfaces. In addition, the flexibility of the layer guarantees its structural integrity during Li plating and stripping. Therefore, our LiBH4-based solid-state electrolyte exhibits a high critical current density (11.43 mA cm-2) and long cycling stability of 5000 h (5.70 mA cm-2) at 25 °C. More importantly, the electrolyte had a wide operational temperature window (-30-150 °C). We believe that our findings provide a perspective with which to avoid dendrite formation in hydride solid-state electrolytes and provide high-performance all-solid-state lithium batteries.
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Non-dissociative chemisorption solid-state storage of hydrogen molecules in host materials is promising to achieve both high hydrogen capacity and uptake rate, but there is the lack of non-dissociative hydrogen storage theories that can guide the rational design of the materials. Herein, we establish generalized design principle to design such materials via the first-principles calculations, theoretical analysis and focused experimental verifications of a series of heteroatom-doped-graphene-supported Ca single-atom carbon nanomaterials as efficient non-dissociative solid-state hydrogen storage materials. An intrinsic descriptor has been proposed to correlate the inherent properties of dopants with the hydrogen storage capability of the carbon-based host materials. The generalized design principle and the intrinsic descriptor have the predictive ability to screen out the best dual-doped-graphene-supported Ca single-atom hydrogen storage materials. The dual-doped materials have much higher hydrogen storage capability than the sole-doped ones, and exceed the current best carbon-based hydrogen storage materials.
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The most well-known criterion for POC devices is ASSURED, and affordability, i.e., using low-cost instrumentation, is the most challenging one. This manuscript provides a pathway for transitioning ESSENCE, an impedance-based biosensor platform, from using an expensive benchtop analyzer-KeySight 4294A (~$50k)-to using a significantly portable and cheaper USB oscilloscope-Analog Discovery 2 (~$200) -with similar sensitivity (around 100 times price difference). To achieve this, we carried out a fundamental study of the interplay between an electrolyte like potassium chloride (KCl), and an electrolyte buffer like phosphate buffered saline (PBS) in the presence and absence of a redox buffer like ferro/ferricyanide system and ([Ru(bpy)3]2+). Redox molecules in the electrolyte caused a significant change in the Nyquist curve of the impedance depending on the redox molecule type. The redox species and the background electrolyte have their own RC semicircles in the Nyquist curve, whose overlap depends on the redox concentration and electrolyte ionic strength. We found that by increasing the electrolyte ionic strength or the redox concentration, the RC semicircle moves to higher frequencies and vice versa. Importantly, the use of the buffer electrolyte, instead of KCl, led to a lower standard deviation and overall signal (lesser sensitivity). However, to achieve the best results from the biorecognition signal, we chose a buffered electrolyte like PBS with high ionic strength and lowered the redox probe concentrations to minimize the standard deviation and reduce any noise from migrating to the low-cost analyzer. Comparing the two analyzers shows similar results, with a lowered detection limit from the low-cost analyzer.