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1.
Cell ; 173(5): 1135-1149.e15, 2018 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-29754817

RESUMO

A primary cause of disease progression in type 2 diabetes (T2D) is ß cell dysfunction due to inflammatory stress and insulin resistance. However, preventing ß cell exhaustion under diabetic conditions is a major therapeutic challenge. Here, we identify the vitamin D receptor (VDR) as a key modulator of inflammation and ß cell survival. Alternative recognition of an acetylated lysine in VDR by bromodomain proteins BRD7 and BRD9 directs association to PBAF and BAF chromatin remodeling complexes, respectively. Mechanistically, ligand promotes VDR association with PBAF to effect genome-wide changes in chromatin accessibility and enhancer landscape, resulting in an anti-inflammatory response. Importantly, pharmacological inhibition of BRD9 promotes PBAF-VDR association to restore ß cell function and ameliorate hyperglycemia in murine T2D models. These studies reveal an unrecognized VDR-dependent transcriptional program underpinning ß cell survival and identifies the VDR:PBAF/BAF association as a potential therapeutic target for T2D.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Receptores de Calcitriol/metabolismo , Fatores de Transcrição/metabolismo , Vitamina D/farmacologia , Animais , Calcitriol/análogos & derivados , Calcitriol/farmacologia , Montagem e Desmontagem da Cromatina , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Humanos , Insulina/sangue , Insulina/metabolismo , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Mutagênese Sítio-Dirigida , Fosforilação Oxidativa/efeitos dos fármacos , Ligação Proteica , Interferência de RNA , RNA Guia de Cinetoplastídeos/genética , RNA Interferente Pequeno/metabolismo , Receptores de Calcitriol/antagonistas & inibidores , Receptores de Calcitriol/genética , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Transcrição Gênica/efeitos dos fármacos
2.
Mol Cell ; 83(19): 3421-3437.e11, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37751740

RESUMO

The nuclear receptor co-repressor (NCoR) complex mediates transcriptional repression dependent on histone deacetylation by histone deacetylase 3 (HDAC3) as a component of the complex. Unexpectedly, we found that signaling by the receptor activator of nuclear factor κB (RANK) converts the NCoR/HDAC3 co-repressor complex to a co-activator of AP-1 and NF-κB target genes that are required for mouse osteoclast differentiation. Accordingly, the dominant function of NCoR/HDAC3 complexes in response to RANK signaling is to activate, rather than repress, gene expression. Mechanistically, RANK signaling promotes RNA-dependent interaction of the transcriptional co-activator PGC1ß with the NCoR/HDAC3 complex, resulting in the activation of PGC1ß and inhibition of HDAC3 activity for acetylated histone H3. Non-coding RNAs Dancr and Rnu12, which are associated with altered human bone homeostasis, promote NCoR/HDAC3 complex assembly and are necessary for RANKL-induced osteoclast differentiation in vitro. These findings may be prototypic for signal-dependent functions of NCoR in other biological contexts.


Assuntos
Osteoclastos , RNA , Humanos , Camundongos , Animais , Proteínas Correpressoras/genética , Osteoclastos/metabolismo , Ligante RANK/genética , Correpressor 1 de Receptor Nuclear/genética , Correpressor 1 de Receptor Nuclear/metabolismo , Expressão Gênica
3.
Cell ; 161(5): 962-963, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-26000475

RESUMO

How do cells maintain the fluidity of cellular membrane in response to temperature fluctuation? In this issue of Cell, Ma et al. identify a regulatory circuit involving a heat-induced acyl-CoA dehydrogenase that controls the lipid saturation level and the fluidity of cellular membranes by transcriptionally regulating a lipid desaturase.


Assuntos
Acil-CoA Desidrogenase/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Ácidos Graxos/metabolismo , Animais
4.
Nature ; 604(7906): 479-485, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35444323

RESUMO

Protonic ceramic electrochemical cells hold promise for operation below 600 °C (refs. 1,2). Although the high proton conductivity of the bulk electrolyte has been demonstrated, it cannot be fully used in electrochemical full cells because of unknown causes3. Here we show that these problems arise from poor contacts between the low-temperature processed oxygen electrode-electrolyte interface. We demonstrate that a simple acid treatment can effectively rejuvenate the high-temperature annealed electrolyte surface, resulting in reactive bonding between the oxygen electrode and the electrolyte and improved electrochemical performance and stability. This enables exceptional protonic ceramic fuel-cell performance down to 350 °C, with peak power densities of 1.6 W cm-2 at 600 °C, 650 mW cm-2 at 450 °C and 300 mW cm-2 at 350 °C, as well as stable electrolysis operations with current densities above 3.9 A cm-2 at 1.4 V and 600 °C. Our work highlights the critical role of interfacial engineering in ceramic electrochemical devices and offers new understanding and practices for sustainable energy infrastructures.

5.
Proc Natl Acad Sci U S A ; 121(2): e2316104121, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38165941

RESUMO

The nuclear receptor corepressor (NCoR) forms a complex with histone deacetylase 3 (HDAC3) that mediates repressive functions of unliganded nuclear receptors and other transcriptional repressors by deacetylation of histone substrates. Recent studies provide evidence that NCoR/HDAC3 complexes can also exert coactivator functions in brown adipocytes by deacetylating and activating PPARγ coactivator 1α (PGC1α) and that signaling via receptor activator of nuclear factor kappa-B (RANK) promotes the formation of a stable NCoR/HDAC3/PGC1ß complex that coactivates nuclear factor kappa-B (NFκB)- and activator protein 1 (AP-1)-dependent genes required for osteoclast differentiation. Here, we demonstrate that activation of Toll-like receptor (TLR) 4, but not TLR3, the interleukin 4 (IL4) receptor nor the Type I interferon receptor, also promotes assembly of an NCoR/HDAC3/PGC1ß coactivator complex. Receptor-specific utilization of TNF receptor-associated factor 6 (TRAF6) and downstream activation of extracellular signal-regulated kinase 1 (ERK1) and TANK-binding kinase 1 (TBK1) accounts for the common ability of RANK and TLR4 to drive assembly of an NCoR/HDAC3/PGC1ß complex in macrophages. ERK1, the p65 component of NFκB, and the p300 histone acetyltransferase (HAT) are also components of the induced complex and are associated with local histone acetylation and transcriptional activation of TLR4-dependent enhancers and promoters. These observations identify a TLR4/TRAF6-dependent signaling pathway that converts NCoR from a corepressor of nuclear receptors to a coactivator of NFκB and AP-1 that may be relevant to functions of NCoR in other developmental and homeostatic processes.


Assuntos
Histonas , Fator 6 Associado a Receptor de TNF , Ativação Transcricional , Proteínas Correpressoras/genética , Histonas/genética , Histonas/metabolismo , Fator 6 Associado a Receptor de TNF/genética , Fator 6 Associado a Receptor de TNF/metabolismo , Fator de Transcrição AP-1/metabolismo , Receptor 4 Toll-Like/metabolismo , Transdução de Sinais , NF-kappa B/genética , NF-kappa B/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo
6.
Cell ; 147(4): 827-39, 2011 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-22078881

RESUMO

Transcriptional coregulators control the activity of many transcription factors and are thought to have wide-ranging effects on gene expression patterns. We show here that muscle-specific loss of nuclear receptor corepressor 1 (NCoR1) in mice leads to enhanced exercise endurance due to an increase of both muscle mass and of mitochondrial number and activity. The activation of selected transcription factors that control muscle function, such as MEF2, PPARß/δ, and ERRs, underpins these phenotypic alterations. NCoR1 levels are decreased in conditions that require fat oxidation, resetting transcriptional programs to boost oxidative metabolism. Knockdown of gei-8, the sole C. elegans NCoR homolog, also robustly increased muscle mitochondria and respiration, suggesting conservation of NCoR1 function. Collectively, our data suggest that NCoR1 plays an adaptive role in muscle physiology and that interference with NCoR1 action could be used to improve muscle function.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Músculo Esquelético/metabolismo , Correpressor 1 de Receptor Nuclear/metabolismo , Animais , Proteínas de Caenorhabditis elegans/genética , Deleção de Genes , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Mitocôndrias Musculares/metabolismo , Desenvolvimento Muscular , Correpressor 1 de Receptor Nuclear/genética , PPAR delta/metabolismo , PPAR beta/metabolismo , Condicionamento Físico Animal
7.
Proc Natl Acad Sci U S A ; 120(52): e2307477120, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38134195

RESUMO

Potassium-ion batteries (PIBs) have attracted ever-increasing interest due to the abundant potassium resources and low cost, which are considered a sustainable energy storage technology. However, the graphite anodes employed in PIBs suffer from low capacity and sluggish reaction kinetics caused by the large radius of potassium ions. Herein, we report nitrogen-doped, defect-rich hollow carbon nanospheres with contact curved interfaces (CCIs) on carbon nanotubes (CNTs), namely CCI-CNS/CNT, to boost both electron transfer and potassium-ion adsorption. Density functional theory calculations validate that engineering CCIs significantly augments the electronic state near the Fermi level, thus promoting electron transfer. In addition, the CCIs exhibit a pronounced affinity for potassium ions, promoting their adsorption and subsequently benefiting potassium storage. As a result, the rationally designed CCI-CNS/CNT anode shows remarkable cyclic stability and rate capability. This work provides a strategy for enhancing the potassium storage performance of carbonaceous materials through CCI engineering, which can be further extended to other battery systems.

8.
Circulation ; 149(3): 227-250, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-37961903

RESUMO

BACKGROUND: Cardiac metabolic dysfunction is a hallmark of heart failure (HF). Estrogen-related receptors ERRα and ERRγ are essential regulators of cardiac metabolism. Therefore, activation of ERR could be a potential therapeutic intervention for HF. However, in vivo studies demonstrating the potential usefulness of ERR agonist for HF treatment are lacking, because compounds with pharmacokinetics appropriate for in vivo use have not been available. METHODS: Using a structure-based design approach, we designed and synthesized 2 structurally distinct pan-ERR agonists, SLU-PP-332 and SLU-PP-915. We investigated the effect of ERR agonist on cardiac function in a pressure overload-induced HF model in vivo. We conducted comprehensive functional, multi-omics (RNA sequencing and metabolomics studies), and genetic dependency studies both in vivo and in vitro to dissect the molecular mechanism, ERR isoform dependency, and target specificity. RESULTS: Both SLU-PP-332 and SLU-PP-915 significantly improved ejection fraction, ameliorated fibrosis, and increased survival associated with pressure overload-induced HF without affecting cardiac hypertrophy. A broad spectrum of metabolic genes was transcriptionally activated by ERR agonists, particularly genes involved in fatty acid metabolism and mitochondrial function. Metabolomics analysis showed substantial normalization of metabolic profiles in fatty acid/lipid and tricarboxylic acid/oxidative phosphorylation metabolites in the mouse heart with 6-week pressure overload. ERR agonists increase mitochondria oxidative capacity and fatty acid use in vitro and in vivo. Using both in vitro and in vivo genetic dependency experiments, we show that ERRγ is the main mediator of ERR agonism-induced transcriptional regulation and cardioprotection and definitively demonstrated target specificity. ERR agonism also led to downregulation of cell cycle and development pathways, which was partially mediated by E2F1 in cardiomyocytes. CONCLUSIONS: ERR agonists maintain oxidative metabolism, which confers cardiac protection against pressure overload-induced HF in vivo. Our results provide direct pharmacologic evidence supporting the further development of ERR agonists as novel HF therapeutics.


Assuntos
Insuficiência Cardíaca , Camundongos , Animais , Cardiomegalia/metabolismo , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Ácidos Graxos/metabolismo
9.
J Biol Chem ; 298(11): 102561, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36198360

RESUMO

Cancer cells have distinctive demands for intermediates from glucose metabolism for biosynthesis and energy in different cell cycle phases. However, how cell cycle regulators and glycolytic enzymes coordinate to orchestrate the essential metabolic processes are still poorly characterized. Here, we report a novel interaction between the mitotic kinase, Aurora A, and the glycolytic enzyme, pyruvate kinase M2 (PKM2), in the interphase of the cell cycle. We found Aurora A-mediated phosphorylation of PKM2 at threonine 45. This phosphorylation significantly attenuated PKM2 enzymatic activity by reducing its tetramerization and also promoted glycolytic flux and the branching anabolic pathways. Replacing the endogenous PKM2 with a nonphosphorylated PKM2 T45A mutant inhibited glycolysis, glycolytic branching pathways, and tumor growth in both in vitro and in vivo models. Together, our study revealed a new protumor function of Aurora A through modulating a rate-limiting glycolytic enzyme, PKM2, mainly during the S phase of the cell cycle. Our findings also showed that although both Aurora A and Aurora B kinase phosphorylate PKM2 at the same residue, the spatial and temporal regulations of the specific kinase and PKM2 interaction are context dependent, indicating intricate interconnectivity between cell cycle and glycolytic regulators.


Assuntos
Leucemia Mieloide Aguda , Piruvato Quinase , Humanos , Piruvato Quinase/metabolismo , Fosforilação , Ácido Pirúvico/metabolismo , Linhagem Celular Tumoral , Glicólise , Divisão Celular
10.
Gastroenterology ; 163(1): 239-256, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35461826

RESUMO

BACKGROUND & AIMS: Mitochondrial dysfunction disrupts the synthesis and secretion of digestive enzymes in pancreatic acinar cells and plays a primary role in the etiology of exocrine pancreas disorders. However, the transcriptional mechanisms that regulate mitochondrial function to support acinar cell physiology are poorly understood. Here, we aim to elucidate the function of estrogen-related receptor γ (ERRγ) in pancreatic acinar cell mitochondrial homeostasis and energy production. METHODS: Two models of ERRγ inhibition, GSK5182-treated wild-type mice and ERRγ conditional knock-out (cKO) mice, were established to investigate ERRγ function in the exocrine pancreas. To identify the functional role of ERRγ in pancreatic acinar cells, we performed histologic and transcriptome analysis with the pancreas isolated from ERRγ cKO mice. To determine the relevance of these findings for human disease, we analyzed transcriptome data from multiple independent human cohorts and conducted genetic association studies for ESRRG variants in 2 distinct human pancreatitis cohorts. RESULTS: Blocking ERRγ function in mice by genetic deletion or inverse agonist treatment results in striking pancreatitis-like phenotypes accompanied by inflammation, fibrosis, and cell death. Mechanistically, loss of ERRγ in primary acini abrogates messenger RNA expression and protein levels of mitochondrial oxidative phosphorylation complex genes, resulting in defective acinar cell energetics. Mitochondrial dysfunction due to ERRγ deletion further triggers autophagy dysfunction, endoplasmic reticulum stress, and production of reactive oxygen species, ultimately leading to cell death. Interestingly, ERRγ-deficient acinar cells that escape cell death acquire ductal cell characteristics, indicating a role for ERRγ in acinar-to-ductal metaplasia. Consistent with our findings in ERRγ cKO mice, ERRγ expression was significantly reduced in patients with chronic pancreatitis compared with normal subjects. Furthermore, candidate locus region genetic association studies revealed multiple single nucleotide variants for ERRγ that are associated with chronic pancreatitis. CONCLUSIONS: Collectively, our findings highlight an essential role for ERRγ in maintaining the transcriptional program that supports acinar cell mitochondrial function and organellar homeostasis and provide a novel molecular link between ERRγ and exocrine pancreas disorders.


Assuntos
Pâncreas Exócrino , Pancreatite Crônica , Células Acinares/patologia , Animais , Estrogênios/metabolismo , Humanos , Camundongos , Camundongos Knockout , Pâncreas/patologia , Pâncreas Exócrino/metabolismo , Pancreatite Crônica/patologia
11.
Crit Rev Biotechnol ; 43(2): 212-226, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35658696

RESUMO

To meet the sustainable development of the swine feed industry, it is essential to find alternative feed resources and develop new feed processing technologies. Distillers dried grains with solubles (DDGS) is a by-product from the ethanol industry consisting of adequate nutrients for swine and is an excellent choice for the swine farming industry. Here, a strategy of co-fermentation of DDGS and lignocellulosic feedstocks for production of swine feed was discussed. The potential of the DDGS and lignocellulosic feedstocks as feedstock for fermented pig feed and the complementary relationship between them were described. In order to facilitate the swine feed research in co-fermentation of DDGS and lignocellulosic feedstocks, the relevant studies on strain selection, fermentation conditions, targeted metabolism, product nutrition, as well as the growth and health of swine were collected and critically reviewed. This review proposed an approach for the production of easily digestible and highly nutritious swine feed via co-fermentation of DDGS and lignocellulosic feedstocks, which could provide a guide for cleaner swine farming, relieve stress on the increasing demand of high-value swine feed, and finally support the ever-increasing demand of the pork market.


Assuntos
Ração Animal , Dieta , Animais , Suínos , Fermentação , Ração Animal/análise , Zea mays , Grão Comestível
12.
J Nanobiotechnology ; 21(1): 41, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36740689

RESUMO

Clinically, activated EGFR mutation associated chemo-drugs resistance has severely threaten NSCLC patients. Nanoparticle based small interfering RNA (siRNA) therapy representing another promising alternative by silencing specific gene while still suffered from charge associated toxicity, strong immunogenicity and poor targetability. Herein, we reported a novel EGFR-mutant NSCLC therapy relying on edible and cation-free kiwi-derived extracellular vesicles (KEVs), which showed sevenfold enhancement of safe dosage compared with widely used cationic liposomes and could be further loaded with Signal Transducer and Activator of Transcription 3 interfering RNA (siSTAT3). siSTAT3 loaded KEVs (STAT3/KEVs) could be easily endowed with EGFR targeting ability (STAT3/EKEVs) and fluorescence by surface modification with tailor-making aptamer through hydrophobic interaction. STAT3/EKEVs with a controlled size of 186 nm displayed excellent stability, high specificity and good cytotoxicity towards EGFR over-expressing and mutant PC9-GR4-AZD1 cells. Intriguingly, the systemic administration of STAT3/EKEVs significantly suppressed subcutaneous PC9-GR4-AZD1 tumor xenografts in nude mice by STAT3 mediated apoptosis. This safe and robust KEVs has emerged as the next generation of gene delivery platform for NSCLC therapy after multiple drug-resistance.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Camundongos , Humanos , RNA Interferente Pequeno/química , Camundongos Nus , Frutas/metabolismo , Linhagem Celular Tumoral , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
13.
Wei Sheng Yan Jiu ; 52(2): 232-238, 2023 Mar.
Artigo em Zh | MEDLINE | ID: mdl-37062685

RESUMO

OBJECTIVE: To analyze the change of drinking water quality in the receiving area of Shijiazhuang South-to-North Water Transfer Project. METHODS: 2029 monitoring data of drinking water in the receiving areas of the South-to-North Water Transfer Project in Shijiazhuang from 2014 to 2021 were collected and collated according to the Sanitary Standard for Drinking Water(GB 5749-2006). Off-work water and pipe water before and after the total coliform group of South-to-North Water Transfer Project, heat-resistant coliform bacteria, escherichia coli, the total number of colonies, arsenic, cadmium, chromium, lead, mercury, nitrate, fluoride, selenium, cyanide, chloroform, carbon tetrachloride, chromaticity and turbidity, odor and taste, visible to the naked eye, pH, aluminum, iron, manganese, copper, zinc, chloride, sulfate, total soluble solids, total hardness, oxygen consumption, volatile phenols, anionic synthetic detergent, ammonia nitrogen, residual chlorine and chlorine dioxide were evaluated and compared. χ~2 test was used to compare the qualified rate, Mann-Whitney rank sum test was used to compare the test values of each index, and simple superposition comprehensive water environmental quality index method was used to evaluate the water quality comprehensively. RESULTS: Before the South-to-North Water Transfer Project, the total qualified rate of drinking water was 84.21%, that of factory water was 81.29%, and that of end water was 85.97%. The total qualified rate of drinking water after the South-to-North Water Transfer Project was 98.72%, that of factory water was 98.89%, and that of end water was 98.66%. The total qualified rate of water quality, the qualified rate of factory water and the qualified rate of end water after the South-to-North water transfer were higher than those before the transfer(P<0.05). The qualified rates of microbial indexes and total hardness of ex-factory water before the South-to-North Water Transfer Project were 94.37% and 89.94%, and those of microbial indexes and total hardness of end water were 94.32% and 93.35%, respectively. After the South-to-North Water Transfer, the qualified rates of microbial indexes and total hardness of the ex-factory water were 100.00% and 98.90%, and the qualified rates of microbial indexes and total hardness of the end water were 100.00% and 99.24%, respectively. After the South-to-North water transfer, the qualified rate of microbial indexes and total hardness of factory water and peripheral water were higher than those before the transfer(P<0.05). After the South-to-North Water Transfer, the M of total coliform group, total colony number, total hardness, fluoride, nitrate nitrogen, chloride, sulfate and dissolved total solids were lower than those before water transfer(For example, the median number of colonies and total hardness of factory water before the South-to-North Water Transfer were 20.00 CFU/100 mL and 248.00 mg/L, respectively. After the South-to-North Water Transfer, the median number of colonies and total hardness were 1.00 CFU/100 mL and 129.00 mg/L, respectively), while the M of trichloromethane, aluminum, pH and oxygen consumption were higher than those before water transfer(For example, the median of trichloromethane and aluminum before the South-to-North Water Transfer is 0.04×10~(-2) and 0.04×10~(-1) mg/L, respectively. After the South-to-North Water Transfer, the median of chloroform and aluminum were 0.06×10~(-2) and 0.25×10~(-1) mg/L, respectively)(P<0.05). The median WQI of comprehensive water environmental quality index before and after the South-to-North Water Transfer was 4.58 and 2.37(P<0.05), respectively. CONCLUSION: The introduction of the South-to-North Water Transfer has significantly improved the quality of drinking water in Shijiazhuang city. Microbial contamination and total hardness exceedance have been greatly improved.


Assuntos
Água Potável , Poluentes Químicos da Água , Qualidade da Água , Clorofórmio , Monitoramento Ambiental/métodos , Fluoretos , Alumínio , Cloretos , Nitratos , Poluentes Químicos da Água/análise , Bactérias , Nitrogênio
14.
J Am Chem Soc ; 144(17): 7657-7666, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35471024

RESUMO

Nanoparticles decorated electrodes (NDEs) are useful in fuel cells, electrolyzers, water treatment, and chemical synthesis. Here, we show that by rapidly bringing a mixed ionic-electronic conductor outside its electrochemical stability window, one can achieve uniform dispersion of metallic nanoparticles inside its bulk and at the surface and improve its electrocatalytic performance when back under normal functional conditions. Surprisingly, this can happen under anodic as well as cathodic current/voltage shocks in an ABO3 perovskite oxide, La0.4Ca0.4Ti0.88Fe0.06Ni0.06O3-δ (LCTFN), across a wide range of H2/O2 gas environments at 800 °C. One possible mechanism for bulk Fe0/Ni0 precipitation under anodic shock condition is the incomplete oxygen oxidation (O2- → Oα-, 0 < α < 2), migration and escape of oxygen to interfaces, and "whiplash" transition-metal reduction due to low electronic conductivity. We show that both cathodic and anodic shocks can produce NDEs to enhance electrocatalytic performance, potentially improving the flexibility of this approach in practical devices.

15.
Small ; 18(12): e2107131, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35064625

RESUMO

Perovskite oxides are widely used in electrochemical cells, profiting from their excellent accommodation of different elements and structure stability. Here, it is reported that when rapidly exceeding the electrochemical stability window of a perovskite oxide through electrochemical treatment, nanoparticles can dynamically exsolve from the perovskite lattice, yielding a nanoparticle decorated material (NDM) with fascinating particle population and distribution. It is reported that as compared to the NDM produced by chemical gas reduction, electrochemical treatment fabricated NDM shows much better electrochemical performance. At 900 °C, a peak power density (PPD) of 896 mW cm-2 (more than tenfold enhancement) is obtained for a yttrium stabilized zirconia (YSZ) electrolyte-supported symmetrical cell with La0.43 Ca0.37 Ti0.8 Co0.1 Fe0.1 O3- δ (LCTCF) electrode after electrochemical treatment for several minutes, while it only reaches to 210 mW cm-2 after chemical gas treatment for tens of hours using humidified hydrogen as fuel. The study establishes a new fairyland for tuning the performance of-but not limited to-the electrochemical cells.

16.
Small ; 18(30): e2201953, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35768285

RESUMO

Porous electrodes that conduct electrons, protons, and oxygen ions with dramatically expanded catalytic active sites can replace conventional electrodes with sluggish kinetics in protonic ceramic electrochemical cells. In this work, a strategy is utilized to promote triple conduction by facilitating proton conduction in praseodymium cobaltite perovskite through engineering non-equivalent B-site Ni/Co occupancy. Surface infrared spectroscopy is used to study the dehydration behavior, which proves the existence of protons in the perovskite lattice. The proton mobility and proton stability are investigated by hydrogen/deuterium (H/D) isotope exchange and temperature-programmed desorption. It is observed that the increased nickel replacement on the B-site has a positive impact on proton defect stability, catalytic activity, and electrochemical performance. This doping strategy is demonstrated to be a promising pathway to increase catalytic activity toward the oxygen reduction and water splitting reactions. The chosen PrNi0.7 Co0.3 O3- δ oxygen electrode demonstrates excellent full-cell performance with high electrolysis current density of -1.48 A cm-2 at 1.3 V and a peak fuel-cell power density of 0.95 W cm-2 at 600 °C and also enables lower-temperature operations down to 350 °C, and superior long-term durability.

17.
J Integr Plant Biol ; 64(5): 1076-1086, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35249256

RESUMO

Male-sterile plants are used in hybrid breeding to improve yield in soybean (Glycine max (L.) Merr.). Developing the capability to alter fertility under different environmental conditions could broaden germplasm resources and simplify hybrid production. However, molecular mechanisms potentially underlying such a system in soybean were unclear. Here, using positional cloning, we identified a gene, MALE STERILITY 3 (MS3), which encodes a nuclear-localized protein containing a plant homeodomain (PHD)-finger domain. A spontaneous mutation in ms3 causing premature termination of MS3 translation and partial loss of the PHD-finger. Transgenetic analysis indicated that MS3 knockout resulted in nonfunctional pollen and no self-pollinated pods, and RNA-seq analysis revealed that MS3 affects the expression of genes associated with carbohydrate metabolism. Strikingly, the fertility of mutant ms3 can restore under long-d conditions. The mutant could thus be used to create a new, more stable photoperiod-sensitive genic male sterility line for two-line hybrid seed production, with significant impact on hybrid breeding and production.


Assuntos
Glycine max , Infertilidade das Plantas , Fertilidade/genética , Proteínas de Homeodomínio , Melhoramento Vegetal , Infertilidade das Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Glycine max/genética , Glycine max/metabolismo
18.
J Virol ; 94(24)2020 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-32967962

RESUMO

As the most severely lethal viral pathogen for crustaceans in both brackish water and freshwater, white spot syndrome virus (WSSV) has a mechanism of infection that remains largely unknown, which profoundly limits the control of WSSV disease. By using a hematopoietic tissue (Hpt) stem cell culture from the red claw crayfish Cherax quadricarinatus suitable for WSSV propagation in vitro, the intracellular trafficking of live WSSV, in which the acidic-pH-dependent endosomal environment was a prerequisite for WSSV fusion, was determined for the first time via live-cell imaging. When the acidic pH within the endosome was alkalized by chemicals, the intracellular WSSV virions were detained in dysfunctional endosomes, resulting in appreciable blocking of the viral infection. Furthermore, disrupted valosin-containing protein (C. quadricarinatus VCP [CqVCP]) activity resulted in considerable aggregation of endocytic WSSV virions in the disordered endosomes, which subsequently recruited autophagosomes, likely by binding to CqGABARAP via CqVCP, to eliminate the aggregated virions within the dysfunctional endosomes. Importantly, both autophagic sorting and the degradation of intracellular WSSV virions were clearly enhanced in Hpt cells with increased autophagic activity, demonstrating that autophagy played a defensive role against WSSV infection. Intriguingly, most of the endocytic WSSV virions were directed to the endosomal delivery system facilitated by CqVCP activity so that they avoided autophagy degradation and successfully delivered the viral genome into Hpt cell nuclei, which was followed by the propagation of progeny virions. These findings will benefit anti-WSSV target design against the most severe viral disease currently affecting farmed crustaceans.IMPORTANCE White spot disease is currently the most devastating viral disease in farmed crustaceans, such as shrimp and crayfish, and has resulted in a severe ecological problem for both brackish water and freshwater aquaculture areas worldwide. Efficient antiviral control of WSSV disease is still lacking due to our limited knowledge of its pathogenesis. Importantly, research on the WSSV infection mechanism is also quite meaningful for the elucidation of viral pathogenesis and virus-host coevolution, as WSSV is one of the largest animal viruses, in terms of genome size, that infects only crustaceans. Here, we found that most of the endocytic WSSV virions were directed to the endosomal delivery system, strongly facilitated by CqVCP, so that they avoided autophagic degradation and successfully delivered the viral genome into the Hpt cell nucleus for propagation. Our data point to a virus-sorting model that might also explain the escape of other enveloped DNA viruses.


Assuntos
Astacoidea/metabolismo , Autofagia/fisiologia , Endossomos/metabolismo , Proteína com Valosina/metabolismo , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Astacoidea/virologia , Técnicas de Cultura de Células , Endossomos/virologia , Doenças dos Peixes/virologia , Concentração de Íons de Hidrogênio , Viroses
19.
BMC Cancer ; 21(1): 24, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33402155

RESUMO

BACKGROUND: The growth- and plasticity-associated protein-43 (GAP43) is biasedly expressed in indigestive system and nervous system. Recent study has shown that GAP43 is responsible for the development of neuronal growth and axonal regeneration in normal nervous tissue, while serves as a specific biomarker of relapsed or refractory neuroblastoma. However, its expression pattern and function in digestive system cancer remains to be clarified. METHODS: In this study, we examined the GAP43 status with qRT-PCR and bisulfite genomic sequencing in colorectal cancer (CRC). We investigated the effect of overexpressed GAP43 in CRC cells with RNA-seq. The RNA-seq data was analyzed with DAVID and IPA. RESULTS: GAP43 was downregulated in CRC compared to the adjacent tissues. DNA methylase inhibitor 5-Aza-CdR treatment could significantly induce GAP43, indicated that the silencing of GAP43 gene in CRC is closely related to DNA methylation. Bisulfite genomic sequencing confirmed the promoter methylation of GAP43 in CRC. To explore the transcriptional alterations by overexpressed GAP43 in CRC, we performed RNA-seq and found that upregulated genes were significantly enriched in the signaling pathways of ABC transporters and ECM-receptor interaction, while downregulated genes were significantly enriched in Ribosome signaling pathway. Further Ingenuity Pathway Analysis (IPA) showed that EIF2 signaling pathway was significantly repressed by overexpression of GAP43. CONCLUSION: Our findings provide a novel mechanistic insight of GAP43 in CRC. Transcriptome profiling of overexpressed GAP43 in CRC uncovered the functional roles of GAP43 in the development of human CRC.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/patologia , Metilação de DNA , Fator de Iniciação 2 em Eucariotos/metabolismo , Proteína GAP-43/metabolismo , Regulação Neoplásica da Expressão Gênica , Transportadores de Cassetes de Ligação de ATP/genética , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Fator de Iniciação 2 em Eucariotos/genética , Proteína GAP-43/genética , Redes Reguladoras de Genes , Humanos , Prognóstico , Regiões Promotoras Genéticas , Transcriptoma , Células Tumorais Cultivadas
20.
Environ Sci Technol ; 55(9): 6239-6247, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33821621

RESUMO

White wastes (unseparated plastics, face masks, textiles, etc.) pose a serious challenge to sustainable human development and the ecosystem and have recently been exacerbated due to the surge in plastic usage and medical wastes from COVID-19. Current recycling methods such as chemical recycling, mechanical recycling, and incineration require either pre-sorting and washing or releasing CO2. In this work, a carbon foam microwave plasma process is developed, utilizing plasma discharge to generate surface temperatures exceeding ∼3000 K in a N2 atmosphere, to convert unsorted white wastes into gases (H2, CO, C2H4, C3H6, CH4, etc.) and small amounts of inorganic minerals and solid carbon, which can be buried as artificial "coal". This process is self-perpetuating, as the new solid carbon asperities grafted onto the foam's surface actually increase the plasma discharge efficiency over time. This process has been characterized by in situ optical probes and infrared sensors and optimized to handle most of the forms of white waste without the need for pre-sorting or washing. Thermal measurement and modeling show that in a flowing reactor, the device can achieve locally extremely high temperatures, but the container wall will still be cold and can be made with cheap materials, and thus, a miniaturized waste incinerator is possible that also takes advantage of intermittent renewable electricity.


Assuntos
COVID-19 , Eliminação de Resíduos , Carbono , Ecossistema , Humanos , Hidrocarbonetos , Micro-Ondas , SARS-CoV-2
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