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1.
Molecules ; 29(18)2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39339487

RESUMO

Solid Oxide Electrolysis Cells (SOECs) can electro-reduce carbon dioxide to carbon monoxide, which not only effectively utilizes greenhouse gases, but also converts excess electrical energy into chemical energy. Perovskite-based oxides with exsolved metal nanoparticles are promising cathode materials for direct electrocatalytic reduction of CO2 through SOECs, and have thus received increasing attention. In this work, we doped Pr0.7Ba0.3MnO3-δ at the B site, and after reduction treatment, metal nanoparticles exsolved and precipitated on the surface of the cathode material, thereby establishing a stable metal-oxide interface structure and significantly improving the electrocatalytic activity of the SOEC cathode materials. Through research, among the Pr0.7Ba0.3Mn1-xNixO3-δ (PBMNx = 0-1) cathode materials, it has been found that the Pr0.7Ba0.3Mn0.9Ni0.1O3-δ (PBMN0.1) electrode material exhibits greater catalytic activity, with a CO yield of 5.36 mL min-1 cm-2 and a Faraday current efficiency of ~99%. After 100 h of long-term testing, the current can still remain stable and there is no significant change in performance. Therefore, the design of this interface has increasing potential for development.

2.
Angew Chem Int Ed Engl ; 63(4): e202315274, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38050771

RESUMO

Alpha alumina (α-Al2 O3 ) are inert materials with outstanding thermal, chemical and mechanical stability. Herein, we fabricate porous single-crystalline (PSC) α-Al2 O3 monoliths at centimeter scale to endow them with high catalytic activity while maintaining their stability. We reduce PSC α-Al2 O3 monoliths to create oxygen vacancies in lattice and stabilize them by the ordered lattice to construct unsaturated Al-O coordination structures for enhancing the catalytic activity. The generation of oxygen vacancy at 18e wyckoff position contributes to the unsaturated Al-O coordination. As a case study, we demonstrate the outstanding performance with conversion (≈34 %) and selectivity (≈95 %) toward non-oxidative dehydrogenation of ethane to ethylene at 700 °C. We achieve the outstanding performance without obvious degradation even after a continuous operation over 1000 hours at 700 °C.

3.
Nutrients ; 15(23)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38068829

RESUMO

Obesity is a chronic metabolic disease that can be induced by a high-fat diet (HFD) and predisposes to a variety of complications. In recent years, various bioactive substances, such as probiotics, prebiotics, and postbiotics, have been widely discussed because of their good anti-lipid and anti-inflammatory activities. In this paper, soybean protein isolate was used as a substrate to prepare the postbiotic. Compound prebiotics (galactose oligosaccharides, fructose oligosaccharides, and lactitol) preparation Aunulife Postbiotics and Prebiotics Composition (AYS) is the research object. Weight loss and bowel movements in mice induced by a high-fat diet were studied. Moreover, qualitative and quantitative analyses of small-molecule metabolites in AYS were performed to identify the functional molecules in AYS. After 12 weeks of feeding, the weight gain of mice that were fed with high-dose AYS (group H) and low-dose AYS (group L) from 4 to 12 weeks was 6.72 g and 5.25 g (p < 0.05), both of which were significantly lower than that of the high-fat diet (group DM, control group) group (7.73 g) (p < 0.05). Serum biochemical analysis showed that TC, TG, and LDL-C levels were significantly lower in mice from the H and L groups (p < 0.05). In addition, the fecal lipid content of mice in the L group reached 5.89%, which was significantly higher than that of the DM group at 4.02% (p < 0.05). The study showed that AYS changed the structure of the intestinal microbiota in mice on a high-fat diet, resulting in a decrease in the relative abundance of Firmicutes and Muribaculaceae and an increase in the relative abundance of Bacteroidetes, Verrucomicrobia, and Lactobacillus. The metabolomics study results of AYS showed that carboxylic acids and derivatives, and organonitrogen compounds accounted for 51.51% of the AYS metabolites, among which pantothenate, stachyose, betaine, and citrate had the effect of preventing obesity in mice. In conclusion, the administration of prebiotics and postbiotic-rich AYS reduces weight gain and increases fecal lipid defecation in obese mice, potentially by regulating the intestinal microbiota of mice on a high-fat diet.


Assuntos
Microbiota , Prebióticos , Animais , Camundongos , Obesidade/metabolismo , Aumento de Peso , Oligossacarídeos/farmacologia , Dieta Hiperlipídica/efeitos adversos , Lipídeos , Camundongos Endogâmicos C57BL
4.
Angew Chem Int Ed Engl ; 62(12): e202300480, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36718945

RESUMO

Introducing pores in single crystals creates a new type of porous materials that incorporate porosity and structural coherence. Herein, we use in situ transmission electron microscopy to disclose the porosity formation by converting KTiOPO4 (KTP) single crystals into porous single-crystalline (PSC) TiO2 monoliths in a solid-solid transformation. The isolated crystalline nuclei of TiO2 clusters with identical lattice orientation on KTP surface moves TiO2 /KTP interface toward mother phase for growing PSC TiO2 monoliths. The relative density in PSC TiO2 monoliths dominates porosity while the macroscopic dimensions remain unchanged in the transformation. The single-crystalline nature of porous architecture stabilizes oxygen vacancy to activate lattice oxygen while the three-dimensional percolation enhances species diffusion. PSC TiO2 monoliths with deposited Pt clusters show enhanced and stable catalytic CO oxidation in air at ∼75 °C for 200 hours of operation.

5.
J Agric Food Chem ; 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36719709

RESUMO

Phosphorylation is a broad post-translational protein modification, and the level of phosphorylation of milk proteins is associated with lactation, coagulation properties, and digestibility. However, phosphoproteins in bovine milk-based and goat milk-based infant formula have not been systematically explored. Here, we have analyzed six bovine and six goat milk-based infant formula using a quantitative phosphoproteomics approach, from which we identified 200 phosphoproteins with 276 phosphorylation sites and 156 phosphorylation sites from 75 phosphoproteins, respectively. Of these, 99 phosphorylation sites from 26 shared phosphoproteins were differentially expressed between bovine and goat milk-based infant formula. Especially, CSN1S1 was the most phosphoprotein with 25 quantified phosphorylation sites. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that the identified phosphoproteins not only provide nutrition to the infant but also have anti-inflammatory, antipathogenic, and other biological functions. Our results shed light on the composition, phosphorylation sites, and biological functions of phosphoproteins in bovine milk and goat milk-based infant formula, which provide new insights into the key role of protein modifications during infant development. It also helps us to better understand the differences in digestibility of infant formula from different animal milk sources and thus guides the choice of milk source for infant formula.

6.
Acc Chem Res ; 56(3): 374-384, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36705591

RESUMO

ConspectusPorous materials have wide applications in the fields of catalysis, separation, and energy conversion and storage. Porous materials contain pores that are specifically designed to achieve expectant performance. The solid phases in porous materials are normally completely continuous to form the basic porous frame while the pores are fluid phase within the solid phase. Single crystals are macroscopic materials in three spatial dimensions with the constituent atoms, ions, molecules, or molecular assemblies arranged in an orderly repeating pattern with the ordered structures. The growth of single crystals is indeed a process to arrange these constituents in three dimensions into a repeating pattern within the materials. Today the applications of single crystals are exponentially growing in wide fields, and single crystals are therefore unacknowledged as the pillars of our modern technology. Introducing porosity into single crystals would be expected to create a new kind of porous material in which the basic porous frames are single-crystalline and free of grain boundaries. The structural symmetry is completely maintained within the basic porous frames which are a continuous solid phase, but it is completely lost inside the pores. The porous architecture is free of grain boundaries, and the fully interconnected skeletons are in single-crystalline states within the basic porous frames. Single crystals with porosities can therefore be considered to be a new kind of porous material, but they are single-crystal-like because the structural symmetry is maintained only in the skeletons and completely lost within the pores. We therefore call them porous single crystals or consider them in porous single-crystalline states to stand out with their structural features. Porous single crystals at the macroscale combine the advantages of porous materials and single crystals to incorporate both porosity and structural coherence in a porous architecture, leading to invaluable opportunities to alter the material's properties by controlling the unique structural features to enhance its performance. However, the growth of single crystals in three dimensions reduces the formation of porosities, leading to a fundamental challenge for introducing porosity into single crystals in a traditional process of crystal growth. In this Account, we report the rational design, growth methodology, and microstructural engineering of porous single crystals in a solid-solid transformation. We rationally design a high-density mother phase in a single-crystalline state and transform it into a low-density new phase in a single-crystalline state to introduce porosities into single crystals even incorporating the removal of specific compositions from the mother phase during the growth of porous single crystals. The porosity can be tailored by controlling the change in relative densities from the mother phase to the porous single crystals while the pore size can be engineered by controlling the fabrication conditions. Considering the unique structural features, we explore their functionalities and applications in photoelectrochemical energy conversion, electrochemical alkane conversion, and electrochemical energy storage. We believe that the materials, if tailored into porous single-crystalline states, would not only find a broad range of applications in other fields but also enable a new path for material innovations.

7.
Nutrients ; 14(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36501068

RESUMO

Evidence suggests that the source of dietary protein may have an impact on insulin resistance, but no studies have explored it in pregnant populations. In this study, we combined a population study and an animal experiment to explore this effect. The population study was conducted with data from NHANES. Multiple linear regression was used to observe the association of protein intake with outcomes, including fasting glucose (GLU), insulin (INS), and HOMA-IR. In the animal experiment, 36 pregnant SD rats in three groups were orally administered 100% animal protein, 50% animal protein and 50% plant protein, or 100% plant protein, respectively. The intervention continued throughout the whole pregnancy. On day 19.5, maternal plasma was collected after overnight fasting, and metabolomics was performed using UPLC-MS. We found plant protein intake was negatively correlated with INS and HOMA-IR in the whole population. During the third trimester, a similar correlation was also observed. The animal experiment also presented the same result. In metabolomic analysis, changes in various metabolites and related pathways including FoxO and mTOR signaling pathways were observed. In conclusion, we found a negative association between dietary plant protein intake and maternal insulin resistance during pregnancy. Changes in some active substances and related metabolic pathways may play an important role.


Assuntos
Resistência à Insulina , Gravidez , Feminino , Ratos , Animais , Proteínas de Vegetais Comestíveis , Inquéritos Nutricionais , Cromatografia Líquida , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Insulina , Glicemia/metabolismo
8.
Angew Chem Int Ed Engl ; 61(50): e202212489, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36263760

RESUMO

Preferential oxidation of CO in H2 (PROX) reaction is a promising solution to the on-board purification of CO-contaminated H2 fuel for use in next-generation proton-exchange membrane fuel cells (PEMFC). However, achieving high CO selectivity, activity and structural stability across the wide temperature window remains a great challenge. Herein, we fabricate centimeter scale interfacial PROX catalysts grown from nanoporous single-crystalline Pr2 O3 and Nd2 O3 monoliths with lattice surface-deposited Pt clusters at nanoscale. We demonstrate complete and selective removal of CO in H2 over an unprecedented wide temperature window (253-403 K). The monoliths are integrated with an operational PEMFC to purify the H2 fuel contaminated with CO (30 ppm) and enable stable power output for >400 h; over two thousand times longer than without. This work demonstrates that the nanoporous single-crystalline oxide monoliths can simultaneously achieve the stability and overall performance required to realize practically useful PEMFCs.

9.
Membranes (Basel) ; 12(9)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36135841

RESUMO

Oxidative coupling of methane can produce various valuable products, such as ethane and ethylene, and solid oxide electrolysis cells (SOECs) can electrolyze CH4 to produce C2H4 and C2H6. In this work, Sr2Fe1.575Mo0.5O6-δ electrode materials were prepared by impregnation and in situ precipitation, and Sr2Fe1.5Mo0.5O6-δ was taken as a reference to study the role of metal-oxide interfaces in the catalytic process. When the Fe/Sr2Fe1.575Mo0.5O6-δ interface is well constructed, the selectivity for C2 can reach 78.18% at 850 °C with a potential of 1.2 V, and the conversion rate of CH4 is 11.61%. These results further prove that a well-constructed metal-oxide interface significantly improves the catalytic activity and facilitates the reaction.

10.
Research (Wash D C) ; 2022: 9861518, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35928301

RESUMO

Engineering the catalytic activity and stability of materials would require the identification of the structural features that can tailor active sites at surfaces. Porous single crystals combine the ordered lattice structures and disordered interconnected pores, and they would therefore provide the advantages of precise structure features to identify and engineer the active sites at surfaces. Herein, we fabricate porous single-crystalline vanadium nitride (VN) at centimeter scale and further dope Fe (Fe0.1V0.9N) and Co (Co0.1V0.9N) in lattice to engineer the active sites at surface. We demonstrate that the active surface is composed of unsaturated coordination of V-N, Fe-N, and Co-N structures which lead to the generation of high-density active sites at the porous single-crystalline monolith surface. The interconnected pores aid the pore-enhanced fluxion to facilitate species diffusion in the porous architectures. In the nonoxidative dehydrogenation of ethane to ethylene, we demonstrate the outstanding performance with ethane conversion of 36% and ethylene selectivity of 99% at 660°C. Remarkably stability as a result of their single-crystalline structure, the monoliths achieve the outstanding performance without degradation being observed even after 200 hours of a continuous operation in a monolithic reactor. This work not only demonstrates the effective structural engineering to simultaneously enhance the stability and overall performance for practically useful catalytic materials but also provide a new route for the element doping of porous single crystals at large scale for the potential application in other fields.

11.
Angew Chem Int Ed Engl ; 61(39): e202209851, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-35932112

RESUMO

Water-gas shift (WGS) reaction at low temperature plays an important role in hydrogen production from fossil fuels and hydrogen purification for proton-exchange membrane fuel cells. However, the activation of H2 O is a critical reaction step that greatly limits the overall performance during WGS reaction. Here we fabricate porous single-crystalline (PSC) MoO3 monoliths at 1 cm scale and deposit atomic-layered Pt clusters at the lattice surface to create the interfacial system toward the low-temperature WGS reaction. The single-crystalline nature stabilizes the oxygen vacancies (VO ) at lattice and facilitates the effective activation of H2 O at the interface. We show the highest Pt-normalized activity of 0.86 molCO molPt -1 s-1 for the ultra-low temperature WGS reaction at 120 °C. The single-crystalline features with enhanced fluxion in porous architectures lead to outstanding performance without visible degradation even after continuous operation for 100 hours.

12.
ACS Appl Mater Interfaces ; 14(28): 32244-32252, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35792079

RESUMO

High-pressure heaters in large volume presses must reconcile potentially contradictory properties, and the whole high-pressure and high-temperature (HPHT) community has been engaged for years to seek a better heater. LaCrO3 (LCO)-based ceramic heaters have been widely applied in multianvil apparatus; however, their performance is far from satisfactory, motivating further research on the chemical optimization strategy and corresponding thermochemical mechanism. Here, we adopted a chemical-screening strategy and manufactured tubular heaters using the electrically, chemically, and mechanically optimized Sr-Cu codoped La0.9Sr0.1Cr0.8Cu0.2O3-δ (LSCCuO-9182). HPHT examinations of cylindrical LSCCuO-9182 heaters on Walker-type multianvil apparatuses demonstrated a small temperature gradient, robust thermochemical stability, and excellent compatibility with high-pressure assemblies below 2273 K and 10 GPa. Thermochemical mechanism analysis revealed that the temperature limitation of the LSCCuO-9182 heater was related to the autoredox process of the Cu dopant and Cr and the exchanging ionic migration of Cu and Mg between the LSCCuO-9182 heater and the MgO sleeve. Our combinatorial strategy coupled with thermochemical mechanism analysis makes the prioritization of contradictory objectives more rational, yields reliable LCO heaters, and sheds light on further improvement of the temperature limitation and thermochemical stability.

13.
Angew Chem Int Ed Engl ; 61(32): e202207211, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35670138

RESUMO

Catalytic conversion of CH4 to C2 H4 plays an important role in the light olefin industry. Here, we report the electrochemical conversion of CH4 to C2 H4 /C2 H6 at the anode with the electrolysis of CO2 to CO at the cathode in a solid oxide electrolyser. We constructed well-defined interfaces that function as three-phase boundaries by exsolving single-crystalline Ni nanoparticles in porous single-crystalline CeO2 monoliths. We engineered the chemical states and flux of active oxygen species for the oxidation of CH4 at the anode by controlling voltage and temperature. We show the unprecedented C2 selectivity (C2 H4 and C2 H6 ) of ≥99.5 % at a CH4 conversion of ≈7 %. The electrolyser exhibits excellent durability without performance degradation being observed in a continuous operation of 100 hours. Our work enables a novel path for the selective conversion of CH4 /CO2 into useful chemicals, and the technique of building well-defined interfaces may find potential applications in other fields.

14.
Food Funct ; 13(12): 6484-6497, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35616505

RESUMO

The aim of this study was to compare the sensitization of αS1-CN in cow and goat's milk in a mouse model. Fifty mice were divided into control group, adjuvant control group, cow's milk αS1-CN sensitized group, goat's milk αS1-CN sensitized group and cross sensitized group. Cow's and goat's milk αS1-CN were used to establish a mouse sensitization model. The results showed that cow's milk αS1-CN had higher allergenicity than goat's milk αS1-CN, as can be seen in significantly increased s-IgE and Th2 cell-related inflammatory factors, the proportion of Th2, and the expression of Th2 cell-related transcription factors. Furthermore, the sensitization of cow's milk αS1-CN damaged the intestinal barrier of mice, caused the leakage of LPS, activated the TLR4-NFκB pathway, and thus resulted in the increase of IFN-γ. In addition, mice allergic to cow's milk αS1-CN were less sensitized to goat's milk αS1-CN.


Assuntos
Hipersensibilidade a Leite , Leite , Alérgenos , Animais , Caseínas , Bovinos , Feminino , Cabras , Camundongos , Hipersensibilidade a Leite/etiologia
15.
J Nutr ; 152(10): 2227-2237, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-35524693

RESUMO

BACKGROUND: Recent studies have reported conflicting associations between egg consumption and the risk of all-cause or cardiovascular disease (CVD) mortality, including ischemic heart disease (IHD) mortality and stroke mortality. With accumulating evidence, up-to-date evidence about the association should be synthesized. OBJECTIVES: We aimed to assess the association of the risk of all-cause and CVD mortality with egg consumption. METHODS: We searched the PubMed, Embase, and Web of Science databases through 3 November, 2021 for observational studies conducted in participants ≥18 y of age and which provided ORs, RRs, or HRs and 95% CIs for ≥3 egg consumption categories or for increased intake of egg addressing the associations of interest. A random-effects model was used to pool the reported risk estimates. Restricted cubic splines were used to examine the dose-response association. RESULTS: Twenty-four articles with 48 reports (25 for all-cause mortality, 11 for CVD mortality, 6 for IHD mortality, and 6 for stroke mortality) involving 11,890,695 participants were included. Intake of each 1-egg/d increment was associated with increased risk of all-cause mortality (RR: 1.06; 95% CI: 1.02, 1.10; P = 0.008), but the association was restricted to women, Americans, and studies with adjustments for hyperlipidemia. Egg consumption was linearly associated with CVD mortality only in participants >60 y of age, Americans, studies with follow-up duration ≥15 y, and studies with adjustments for hyperlipidemia (P ≤ 0.018). No significant association was found between egg consumption and IHD or stroke mortality (P ≥ 0.080). CONCLUSIONS: Egg consumption was linearly associated with a modestly increased risk of all-cause mortality and, in older participants, Americans, and studies with longer follow-up or adjustments for hyperlipidemia, CVD mortality. These findings suggest that it may be prudent to avoid high egg consumption.


Assuntos
Doenças Cardiovasculares , Isquemia Miocárdica , Acidente Vascular Cerebral , Idoso , Doenças Cardiovasculares/etiologia , Bases de Dados Factuais , Feminino , Humanos , Fatores de Risco
16.
Food Chem ; 387: 132844, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35398682

RESUMO

Different drying techniques impart distinguishing characteristics to goat milk, particularly to its fat globules. Here, we investigated the difference between freeze-dried and spray-dried goat milk (FGM and SGM) fat globules on lipid profiling and in vitro infant gastrointestinal digestibility. The former presented higher levels of MUFA (31.76%) and lower cholesterol content (1.20 ± 0.02 mg/g). Some important long-chain polyunsaturated triacylglycerols such as POL (16:0/18:1/18:2), PSL (16:0/18:0/18:2), and POO (16:0/18:1/18:1), also had better preservation in FGM. Moreover, we detected more species of lysophospholipid in FGM than SGM, accounting for 2.51% and 0.71% of total phospholipids, respectively. More intriguingly, FGM, which has better membrane integrity and larger particle size, showed longer lag during gastric digestion and lower level of final lipolysis throughout gastrointestinal digestion. Therefore, our results showed the effects of different drying techniques on lipid profiling and digestibility of goat milk, providing significant insight for appropriate utilization of goat milk in infant nutrition.


Assuntos
Cabras , Leite , Animais , Liofilização , Humanos , Lipólise , Fosfolipídeos
17.
Transl Cancer Res ; 11(2): 403-413, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35281421

RESUMO

Background: Gliomas have been known as the most common intracranial malignant tumor, and this kind of tumors cause huge amounts of mortality. The NF-κB inhibitor BAY 11-7821 has been reported as a novel approach in the immunotherapy of lung diseases. However, the functional role of BAY 11-7821 and its association with autophagy in glioma cells have not yet been reported. Methods: In this study, 2 glioma cell lines (U87 and U251) were treated with different doses of BAY 11-7821, or combined with authphagy inhibitor, 3-MA. Afterwards, Transwell assay, CCK-8 assay, EdU staining, Western blot and immunofluorescence assay was used to detected the cell migration, invasion, vability, autophagy in U87 and U251. Results: Our data showed that BAY 11-7821 significantly suppressed the viability, proliferation, migration, and invasion of glioma cells in a dose-dependent manner. At the molecular level, BAY 11-7821 downregulated the protein levels of p-IκBα, p-p65, NLRP3, and p62, and upregulated the protein levels of caspase 3 and Bax, as well as decreased the levels of IL-1ß and IL-18. Results showed BAY 11-7821 enhanced autophagy. While, Pre-treatment with 3-MA, an autophagy inhibitor, obviously reversed the effects of BAY 11-7821 on malignant biological behaviors of glioma cell, inflammation status, and autophagy. Conclusions: In this study, we found that BAY 11-7821 has an effective inhibitive function on malignant biological behaviors by mediating autophagy. Our findings contribute to a better understanding of BAY 11-7821 as a potential anticancer drug in glioma via activating autophagy.

18.
Angew Chem Int Ed Engl ; 61(1): e202113079, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34676642

RESUMO

Dry reforming of CH4 /CO2 provides an attractive route to convert greenhouse gas into syngas; however, the resistance to sintering and coking of catalyst remains a fundamental challenge at high operation temperatures. Here we create active and durable metal-oxide interfaces in porous single-crystalline (PSC) CeO2 monoliths with in situ exsolved single-crystalline (SC) Ni particles and show efficient dry reforming of CH4 /CO2 at temperatures as low as 450 °C. We show the excellent and durable performance with ≈20 % of CH4 conversion and ≈30 % of CO2 conversion even in a continuous operation of 240 hours. The well-defined active metal-oxide interfaces, created by exsolving SC Ni nanoparticles from PSC Nix Ce1-x O2 to anchor them on PSC CeO2 scaffolds, prevent nanoparticle sintering and enhance the coking resistance due to the stronger metal-support interactions. Our work would enable an industrially and economically viable path for carbon reclamation, and the technique of creating active and durable metal-oxide interfaces in PSC monoliths could lead to stable catalyst designs for many challenging reactions.

19.
Front Cardiovasc Med ; 8: 737191, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604360

RESUMO

Background: Endogenous hydrogen sulfide (H2S) is emerging as a key signal molecule in the development of diabetic cardiomyopathy. The aim of this study was to explore the effect and underlying mechanism of S-propargyl-cysteine (SPRC), a novel modulator of endogenous H2S, on diabetic cardiomyopathy in db/db diabetic mice. Methods and Results: Vehicle or SPRC were orally administered to 8-month-old male db/db mice and their wild type littermate for 12 weeks. SPRC treatment ameliorated myocardial hypertrophy, fibrosis, and cardiac systolic dysfunction assessed by histopathological examinations and echocardiography. The functional improvement by SPRC was accompanied by a reduction in myocardial lipid accumulation and ameliorated plasma lipid profiles. SPRC treatment improved glucose tolerance in db/db mice, with fasting blood glucose and peripheral insulin resistance remaining unchanged. Furthermore, insulin receptor signaling involving the phosphorylation of protein kinase B (Akt/PKB) and glycogen synthase kinase 3ß (GSK3ß) were elevated and activated by SPRC treatment. Primary neonatal mice cardiomyocytes were cultured to explore the mechanisms of SPRC on diabetic cardiomyopathy in vitro. Consistent with the results in vivo, SPRC not only up-regulated insulin receptor signaling pathway in cardiomyocytes in dose-dependent manner in the basal state, but also relieved the suppression of insulin receptor signaling induced by high concentrations of glucose and insulin. Furthermore, SPRC also enhanced the expression of glucose transporter 4 (GLUT4) and 3H glucose uptake in cardiomyocytes. Conclusions: In this study, we found a novel beneficial effect of SPRC on diabetic cardiomyopathy, which was associated with activation of insulin receptor signaling. SPRC may be a promising medication for diabetic cardiomyopathy in type 2 diabetes mellitus patients.

20.
PLoS One ; 16(10): e0256984, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34618822

RESUMO

Wheat is an important global staple food crop; however, its productivity is severely hampered by changing climate. Erratic rain patterns cause terminal drought stress, which affect reproductive development and crop yield. This study investigates the potential and zinc (Zn) and silicon (Si) to ameliorate terminal drought stress in wheat and associated mechanisms. Two different drought stress levels, i.e., control [80% water holding capacity (WHC) was maintained] and terminal drought stress (40% WHC maintained from BBCH growth stage 49 to 83) combined with five foliar-applied Zn-Si combinations (i.e., control, water spray, 4 mM Zn, 40 mM Si, 4 mM Zn + 40 mM Si applied 7 days after the initiation of drought stress). Results revealed that application of Zn and Si improved chlorophyll and relative water contents under well-watered conditions and terminal drought stress. Foliar application of Si and Zn had significant effect on antioxidant defense mechanism, proline and soluble protein, which showed that application of Si and Zn ameliorated the effects of terminal drought stress mainly by regulating antioxidant defense mechanism, and production of proline and soluble proteins. Combined application of Zn and Si resulted in the highest improvement in growth and antioxidant defense. The application of Zn and Si improved yield and related traits, both under well-watered conditions and terminal drought stress. The highest yield and related traits were recorded for combined application of Zn and Si. For grain and biological yield differences among sole and combined Zn-Si application were statistically non-significant (p>0.05). In conclusion, combined application of Zn-Si ameliorated the adverse effects of terminal drought stress by improving yield through regulating antioxidant mechanism and production of proline and soluble proteins. Results provide valuable insights for further cross talk between Zn-Si regulatory pathways to enhance grain biofortification.


Assuntos
Silício/metabolismo , Triticum/fisiologia , Zinco/metabolismo , Antioxidantes/metabolismo , Clorofila/metabolismo , Secas , Silício/administração & dosagem , Estresse Fisiológico , Água/metabolismo , Zinco/administração & dosagem
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