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1.
Genes Dev ; 38(3-4): 168-188, 2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38479840

RESUMEN

CTCF is crucial for chromatin structure and transcription regulation in early embryonic development. However, the kinetics of CTCF chromatin occupation in preimplantation embryos have remained unclear. In this study, we used CUT&RUN technology to investigate CTCF occupancy in mouse preimplantation development. Our findings revealed that CTCF begins binding to the genome prior to zygotic genome activation (ZGA), with a preference for CTCF-anchored chromatin loops. Although the majority of CTCF occupancy is consistently maintained, we identified a specific set of binding sites enriched in the mouse-specific short interspersed element (SINE) family B2 that are restricted to the cleavage stages. Notably, we discovered that the neuroprotective protein ADNP counteracts the stable association of CTCF at SINE B2-derived CTCF-binding sites. Knockout of Adnp in the zygote led to impaired CTCF binding signal recovery, failed deposition of H3K9me3, and transcriptional derepression of SINE B2 during the morula-to-blastocyst transition, which further led to unfaithful cell differentiation in embryos around implantation. Our analysis highlights an ADNP-dependent restriction of CTCF binding during cell differentiation in preimplantation embryos. Furthermore, our findings shed light on the functional importance of transposable elements (TEs) in promoting genetic innovation and actively shaping the early embryo developmental process specific to mammals.


Asunto(s)
Cromatina , Desarrollo Embrionario , Animales , Ratones , Sitios de Unión , Blastocisto/metabolismo , Cromatina/metabolismo , Desarrollo Embrionario/genética , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/metabolismo , Mamíferos , Ratones Noqueados , Proteínas del Tejido Nervioso/metabolismo , Cigoto/metabolismo
2.
Nature ; 589(7842): 396-401, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33473229

RESUMEN

The water-gas shift (WGS) reaction is an industrially important source of pure hydrogen (H2) at the expense of carbon monoxide and water1,2. This reaction is of interest for fuel-cell applications, but requires WGS catalysts that are durable and highly active at low temperatures3. Here we demonstrate that the structure (Pt1-Ptn)/α-MoC, where isolated platinum atoms (Pt1) and subnanometre platinum clusters (Ptn) are stabilized on α-molybdenum carbide (α-MoC), catalyses the WGS reaction even at 313 kelvin, with a hydrogen-production pathway involving direct carbon monoxide dissociation identified. We find that it is critical to crowd the α-MoC surface with Pt1 and Ptn species, which prevents oxidation of the support that would cause catalyst deactivation, as seen with gold/α-MoC (ref. 4), and gives our system high stability and a high metal-normalized turnover number of 4,300,000 moles of hydrogen per mole of platinum. We anticipate that the strategy demonstrated here will be pivotal for the design of highly active and stable catalysts for effective activation of important molecules such as water and carbon monoxide for energy production.

3.
Proc Natl Acad Sci U S A ; 121(13): e2310469121, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38502692

RESUMEN

The incessant mutations of viruses, variable immune responses, and likely emergence of new viral threats necessitate multiple approaches to novel antiviral therapeutics. Furthermore, the new antiviral agents should have broad-spectrum activity and be environmentally stable. Here, we show that biocompatible tapered CuS nanoparticles (NPs) efficiently agglutinate coronaviruses with binding affinity dependent on the chirality of surface ligands and particle shape. L-penicillamine-stabilized NPs with left-handed curved apexes display half-maximal inhibitory concentrations (IC50) as low as 0.66 pM (1.4 ng/mL) and 0.57 pM (1.2 ng/mL) for pseudo-type SARS-CoV-2 viruses and wild-type Wuhan-1 SARS-CoV-2 viruses, respectively, which are about 1,100 times lower than those for antibodies (0.73 nM). Benefiting from strong NPs-protein interactions, the same particles are also effective against other strains of coronaviruses, such as HCoV-HKU1, HCoV-OC43, HCoV-NL63, and SARS-CoV-2 Omicron variants with IC50 values below 10 pM (21.8 ng/mL). Considering rapid response to outbreaks, exposure to elevated temperatures causes no change in the antiviral activity of NPs while antibodies are completely deactivated. Testing in mice indicates that the chirality-optimized NPs can serve as thermally stable analogs of antiviral biologics complementing the current spectrum of treatments.


Asunto(s)
COVID-19 , Coronavirus Humano OC43 , Humanos , Animales , Ratones , SARS-CoV-2/genética , Anticuerpos/farmacología , Antivirales/farmacología , Antivirales/uso terapéutico
4.
Brief Bioinform ; 25(4)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38886006

RESUMEN

Reconstructing the topology of gene regulatory network from gene expression data has been extensively studied. With the abundance functional transcriptomic data available, it is now feasible to systematically decipher regulatory interaction dynamics in a logic form such as a Boolean network (BN) framework, which qualitatively indicates how multiple regulators aggregated to affect a common target gene. However, inferring both the network topology and gene interaction dynamics simultaneously is still a challenging problem since gene expression data are typically noisy and data discretization is prone to information loss. We propose a new method for BN inference from time-series transcriptional profiles, called LogicGep. LogicGep formulates the identification of Boolean functions as a symbolic regression problem that learns the Boolean function expression and solve it efficiently through multi-objective optimization using an improved gene expression programming algorithm. To avoid overly emphasizing dynamic characteristics at the expense of topology structure ones, as traditional methods often do, a set of promising Boolean formulas for each target gene is evolved firstly, and a feed-forward neural network trained with continuous expression data is subsequently employed to pick out the final solution. We validated the efficacy of LogicGep using multiple datasets including both synthetic and real-world experimental data. The results elucidate that LogicGep adeptly infers accurate BN models, outperforming other representative BN inference algorithms in both network topology reconstruction and the identification of Boolean functions. Moreover, the execution of LogicGep is hundreds of times faster than other methods, especially in the case of large network inference.


Asunto(s)
Algoritmos , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Perfilación de la Expresión Génica/métodos , Humanos , Transcriptoma , Programas Informáticos , Biología Computacional/métodos , Redes Neurales de la Computación
5.
Brief Bioinform ; 25(4)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38855914

RESUMEN

Cluster analysis, a pivotal step in single-cell sequencing data analysis, presents substantial opportunities to effectively unveil the molecular mechanisms underlying cellular heterogeneity and intercellular phenotypic variations. However, the inherent imperfections arise as different clustering algorithms yield diverse estimates of cluster numbers and cluster assignments. This study introduces Single Cell Consistent Clustering based on Spectral Matrix Decomposition (SCSMD), a comprehensive clustering approach that integrates the strengths of multiple methods to determine the optimal clustering scheme. Testing the performance of SCSMD across different distances and employing the bespoke evaluation metric, the methodological selection undergoes validation to ensure the optimal efficacy of the SCSMD. A consistent clustering test is conducted on 15 authentic scRNA-seq datasets. The application of SCSMD to human embryonic stem cell scRNA-seq data successfully identifies known cell types and delineates their developmental trajectories. Similarly, when applied to glioblastoma cells, SCSMD accurately detects pre-existing cell types and provides finer sub-division within one of the original clusters. The results affirm the robust performance of our SCSMD method in terms of both the number of clusters and cluster assignments. Moreover, we have broadened the application scope of SCSMD to encompass larger datasets, thereby furnishing additional evidence of its superiority. The findings suggest that SCSMD is poised for application to additional scRNA-seq datasets and for further downstream analyses.


Asunto(s)
Algoritmos , Análisis de la Célula Individual , Humanos , Análisis de la Célula Individual/métodos , Análisis por Conglomerados , Biología Computacional/métodos , Glioblastoma/genética , Glioblastoma/patología , Glioblastoma/metabolismo
6.
Proc Natl Acad Sci U S A ; 120(27): e2300493120, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37364112

RESUMEN

Fast transport of charge carriers in semiconductor photoelectrodes are a major determinant of the solar-to-hydrogen efficiency for photoelectrochemical (PEC) water slitting. While doping metal ions as single atoms/clusters in photoelectrodes has been popularly used to regulate their charge transport, PEC performances are often low due to the limited charge mobility and severe charge recombination. Here, we disperse Ru and P diatomic sites onto hematite (DASs Ru-P:Fe2O3) to construct an efficient photoelectrode inspired by the concept of correlated single-atom engineering. The resultant photoanode shows superior photocurrent densities of 4.55 and 6.5 mA cm-2 at 1.23 and 1.50 VRHE, a low-onset potential of 0.58 VRHE, and a high applied bias photon-to-current conversion efficiency of 1.00% under one sun illumination, which are much better than the pristine Fe2O3. A detailed dynamic analysis reveals that a remarkable synergetic ineraction of the reduced recombination by a low Ru doping concentration with substitution of Fe site as well as the construction of Ru-P bonds in the material increases the carrier separation and fast charge transportation dynamics. A systematic simulation study further proves the superiority of the Ru-P bonds compared to the Ru-O bonds, which allows more long-lived carriers to participate in the water oxidation reaction. This work offers an effective strategy for enhancing charge carrier transportation dynamics by constructing pair sites into semiconductors, which may be extended to other photoelectrodes for solar water splitting.

7.
Proc Natl Acad Sci U S A ; 120(15): e2300197120, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37018192

RESUMEN

Composite-polymer-electrolytes (CPEs) embedded with advanced filler materials offer great promise for fast and preferential Li+ conduction. The filler surface chemistry determines the interaction with electrolyte molecules and thus critically regulates the Li+ behaviors at the interfaces. Herein, we probe into the role of electrolyte/filler interfaces (EFI) in CPEs and promote Li+ conduction by introducing an unsaturated coordination Prussian blue analog (UCPBA) filler. Combining scanning transmission X-ray microscope stack imaging studies and first-principle calculations, fast Li+ conduction is revealed only achievable at a chemically stable EFI, which can be established by the unsaturated Co-O coordination in UCPBA to circumvent the side reactions. Moreover, the as-exposed Lewis-acid metal centers in UCPBA efficiently attract the Lewis-base anions of Li salts, which facilitates the Li+ disassociation and enhances its transference number (tLi+). Attributed to these superiorities, the obtained CPEs realize high room-temperature ionic conductivity up to 0.36 mS cm-1 and tLi+ of 0.6, enabling an excellent cyclability of lithium metal electrodes over 4,000 h as well as remarkable capacity retention of 97.6% over 180 cycles at 0.5 C for solid-state lithium-sulfur batteries. This work highlights the crucial role of EFI chemistry in developing highly conductive CPEs and high-performance solid-state batteries.

8.
Plant J ; 117(3): 840-855, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37938788

RESUMEN

Optimal grain-appearance quality is largely determined by grain size. To date, dozens of grain size-related genes have been identified. However, the regulatory mechanism of slender grain formation is not fully clear. We identified the OsSG34 gene by map-based cloning. A 9-bp deletion on 5'-untranslated region of OsSG34, which resulted in the expression difference between the wild-type and sg34 mutant, led to the slender grains and good transparency in sg34 mutant. OsSG34 as an α/ß fold triacylglycerol lipase affected the triglyceride content directly, and the components of cell wall indirectly, especially the lignin between the inner and outer lemmas in rice grains, which could affect the change in grain size by altering cell proliferation and expansion, while the change in starch content and starch granule arrangement in endosperm could affect the grain-appearance quality. Moreover, the OsERF71 was identified to directly bind to cis-element on the mutant site, thereby regulating the OsSG34 expression. Knockout of three OsSG34 homologous genes resulted in slender grains as well. The study demonstrated OsSG34, involved in lipid metabolism, affected grain size and quality. Our findings suggest that the OsSG34 gene could be used in rice breeding for high yield and good grain-appearance quality via marker-assisted selection and gene-editing approaches.


Asunto(s)
Oryza , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fitomejoramiento , Endospermo/genética , Endospermo/metabolismo , Grano Comestible/genética , Grano Comestible/metabolismo , Almidón/metabolismo
9.
J Virol ; 98(2): e0140823, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38189252

RESUMEN

Autophagy generally functions as a cellular surveillance mechanism to combat invading viruses, but viruses have evolved various strategies to block autophagic degradation and even subvert it to promote viral propagation. White spot syndrome virus (WSSV) is the most highly pathogenic crustacean virus, but little is currently known about whether crustacean viruses such as WSSV can subvert autophagic degradation for escape. Here, we show that even though WSSV proliferation triggers the accumulation of autophagosomes, autophagic degradation is blocked in the crustacean species red claw crayfish. Interestingly, the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex including CqSNAP29, CqVAMP7, and the novel autophagosome SNARE protein CqSyx12 is required for autophagic flux to restrict WSSV replication, as revealed by gene silencing experiments. Simultaneously, the expressed WSSV tegument protein VP26, which likely localizes on autophagic membrane mediated by its transmembrane region, binds the Qb-SNARE domain of CqSNAP29 to competitively inhibit the binding of CqSyx12-Qa-SNARE with CqSNAP29-Qb-SNARE; this in turn disrupts the assembly of the CqSyx12-SNAP29-VAMP7 SNARE complex, which is indispensable for the proposed fusion of autophagosomes and lysosomes. Consequently, the autophagic degradation of WSSV is likely suppressed by the expressed VP26 protein in vivo in crayfish, thus probably protecting WSSV components from degradation via the autophagosome-lysosome pathway, resulting in evasion by WSSV. Collectively, these findings highlight how a DNA virus can subvert autophagic degradation by impairing the assembly of the SNARE complex to achieve evasion, paving the way for understanding host-DNA virus interactions from an evolutionary point of view, from crustaceans to mammals.IMPORTANCEWhite spot syndrome virus (WSSV) is one of the largest animal DNA viruses in terms of its genome size and has caused huge economic losses in the farming of crustaceans such as shrimp and crayfish. Detailed knowledge of WSSV-host interactions is still lacking, particularly regarding viral escape from host immune clearance. Intriguingly, we found that the presence of WSSV-VP26 might inhibit the autophagic degradation of WSSV in vivo in the crustacean species red claw crayfish. Importantly, this study is the first to show that viral protein VP26 functions as a core factor to benefit WSSV escape by disrupting the assembly of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex, which is necessary for the proposed fusion of autophagosomes with lysosomes for subsequent degradation. These findings highlight a novel mechanism of DNA virus evasion by blocking SNARE complex assembly and identify viral VP26 as a key candidate for anti-WSSV targeting.


Asunto(s)
Astacoidea , Autofagia , Virus del Síndrome de la Mancha Blanca 1 , Animales , Astacoidea/metabolismo , Autofagosomas/metabolismo , Proteínas Qb-SNARE/metabolismo , Proteínas SNARE/genética , Proteínas SNARE/metabolismo , Proteínas Solubles de Unión al Factor Sensible a la N-Etilmaleimida , Virus del Síndrome de la Mancha Blanca 1/fisiología
10.
Diabetologia ; 67(3): 528-546, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38127123

RESUMEN

AIMS/HYPOTHESIS: Diabetes mellitus is associated with impaired insulin secretion, often aggravated by oversecretion of glucagon. Therapeutic interventions should ideally correct both defects. Glucagon-like peptide 1 (GLP-1) has this capability but exactly how it exerts its glucagonostatic effect remains obscure. Following its release GLP-1 is rapidly degraded from GLP-1(7-36) to GLP-1(9-36). We hypothesised that the metabolite GLP-1(9-36) (previously believed to be biologically inactive) exerts a direct inhibitory effect on glucagon secretion and that this mechanism becomes impaired in diabetes. METHODS: We used a combination of glucagon secretion measurements in mouse and human islets (including islets from donors with type 2 diabetes), total internal reflection fluorescence microscopy imaging of secretory granule dynamics, recordings of cytoplasmic Ca2+ and measurements of protein kinase A activity, immunocytochemistry, in vivo physiology and GTP-binding protein dissociation studies to explore how GLP-1 exerts its inhibitory effect on glucagon secretion and the role of the metabolite GLP-1(9-36). RESULTS: GLP-1(7-36) inhibited glucagon secretion in isolated islets with an IC50 of 2.5 pmol/l. The effect was particularly strong at low glucose concentrations. The degradation product GLP-1(9-36) shared this capacity. GLP-1(9-36) retained its glucagonostatic effects after genetic/pharmacological inactivation of the GLP-1 receptor. GLP-1(9-36) also potently inhibited glucagon secretion evoked by ß-adrenergic stimulation, amino acids and membrane depolarisation. In islet alpha cells, GLP-1(9-36) led to inhibition of Ca2+ entry via voltage-gated Ca2+ channels sensitive to ω-agatoxin, with consequential pertussis-toxin-sensitive depletion of the docked pool of secretory granules, effects that were prevented by the glucagon receptor antagonists REMD2.59 and L-168049. The capacity of GLP-1(9-36) to inhibit glucagon secretion and reduce the number of docked granules was lost in alpha cells from human donors with type 2 diabetes. In vivo, high exogenous concentrations of GLP-1(9-36) (>100 pmol/l) resulted in a small (30%) lowering of circulating glucagon during insulin-induced hypoglycaemia. This effect was abolished by REMD2.59, which promptly increased circulating glucagon by >225% (adjusted for the change in plasma glucose) without affecting pancreatic glucagon content. CONCLUSIONS/INTERPRETATION: We conclude that the GLP-1 metabolite GLP-1(9-36) is a systemic inhibitor of glucagon secretion. We propose that the increase in circulating glucagon observed following genetic/pharmacological inactivation of glucagon signalling in mice and in people with type 2 diabetes reflects the removal of GLP-1(9-36)'s glucagonostatic action.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hipoglucemia , Islotes Pancreáticos , Fragmentos de Péptidos , Humanos , Glucagón/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Péptido 1 Similar al Glucagón/metabolismo , Islotes Pancreáticos/metabolismo , Hipoglucemia/metabolismo , Insulina/metabolismo
11.
J Am Chem Soc ; 146(25): 17189-17200, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38864358

RESUMEN

Spatial immobilization of fragile enzymes using a nanocarrier is an efficient means to design heterogeneous biocatalysts, presenting superior stability and recyclability to pristine enzymes. An immobilized enzyme, however, usually compromises its catalytic activity because of inevasible mass transfer issues and the unfavorable conformation changes in a confined environment. Here, we describe a synergetic metal-organic framework pore-engineering strategy to trap lipase (an important hydrolase), which confers lipase-boosted stability and activity simultaneously. The hierarchically porous NU-1003, featuring interconnected mesopore and micropore channels, is precisely modified by chain-adjustable fatty acids on its mesopore channel, into which lipase is trapped. The interconnected pore structure ensures efficient communication between trapped lipase and exterior media, while the fatty acid-mediated hydrophobic pore can activate the opening conformation of lipase by interfacial interaction. Such dual pore compartmentalization and hydrophobization activation effects render the catalytic center of trapped lipase highly accessible, resulting in 1.57-fold and 2.46-fold activities as native lipase on ester hydrolysis and enantioselective catalysis. In addition, the feasibility of these heterogeneous biocatalysts for kinetic resolution of enantiomer is also validated, showing much higher efficiency than native lipase.


Asunto(s)
Estabilidad de Enzimas , Enzimas Inmovilizadas , Interacciones Hidrofóbicas e Hidrofílicas , Lipasa , Lipasa/química , Lipasa/metabolismo , Porosidad , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Estructuras Metalorgánicas/química , Hidrólisis , Biocatálisis
12.
J Am Chem Soc ; 146(9): 6397-6407, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38394777

RESUMEN

Catalyst supports play an essential role in catalytic reactions, hinting at pronounced metal-support effects. Zeolites are a propitious support in heterogeneous catalysts, while their use in the electrocatalytic CO2 reduction reaction has been limited as yet because of their electrically insulating nature and serious competing hydrogen evolution reaction (HER). Enlightened by theoretical prediction, herein, we implant zinc ions into the structural skeleton of a zeolite Y to strategically tailor a favorable electrocatalytic platform with remarkably enhanced electronic conduction and strong HER inhibition capability, which incorporates ultrafine cadmium oxide nanoclusters as guest species into the supercages of the tailored 12-ring window framework. The metal d-bandwidth tuning of cadmium by skeletal zinc steers the extent of substrate-molecule orbital mixing, enhancing the stabilization of the key intermediate *COOH while weakening the CO poisoning effect. Furthermore, the strong cadmium-zinc interplay causes a considerable thermodynamic barrier for water dissociation in the conversion of H+ to *H, potently suppressing the competing HER. Therefore, we achieve an industrial-level partial current density of 335 mA cm-2 and remarkable Faradaic efficiency of 97.1% for CO production and stably maintain Faradaic efficiency above 90% at the industrially relevant current density for over 120 h. This work provides a proof of concept of tailored conductive zeolite as a favorable electrocatalytic support for industrial-level CO2 electrolysis and will significantly enhance the adaptability of conductive zeolite-based electrocatalysts in a variety of electrocatalysis and energy conversion applications.

13.
Thorax ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38871465

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a lethal lung disease for which there are no reliable biomarkers or disease-modifying drugs. Here, we integrated human genomics and proteomics to investigate the causal associations between 2769 plasma proteins and IPF. Our Mendelian randomisation analysis identified nine proteins associated with IPF, of which three (FUT3, ADAM15 and USP28) were colocalised. ADAM15 emerged as the top candidate, supported by expression quantitative trait locus analysis in both blood and lung tissue. These findings provide novel insights into the aetiology of IPF and offer translational opportunities in response to the clinical challenges of this devastating disease.

14.
J Neuroinflammation ; 21(1): 29, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38246987

RESUMEN

Demyelination and failure of remyelination in the central nervous system (CNS) characterize a number of neurological disorders. Spontaneous remyelination in demyelinating diseases is limited, as oligodendrocyte precursor cells (OPCs), which are often present in demyelinated lesions in abundance, mostly fail to differentiate into oligodendrocytes, the myelinating cells in the CNS. In addition to OPCs, the lesions are assembled numbers of activated resident microglia/infiltrated macrophages; however, the mechanisms and potential role of interactions between the microglia/macrophages and OPCs are poorly understood. Here, we generated a transcriptional profile of exosomes from activated microglia, and found that miR-615-5p was elevated. miR-615-5p bound to 3'UTR of myelin regulator factor (MYRF), a crucial myelination transcription factor expressed in oligodendrocyte lineage cells. Mechanistically, exosomes from activated microglia transferred miR-615-5p to OPCs, which directly bound to MYRF and inhibited OPC maturation. Furthermore, an effect of AAV expressing miR-615-5p sponge in microglia was tested in experimental autoimmune encephalomyelitis (EAE) and cuprizone (CPZ)-induced demyelination model, the classical mouse models of multiple sclerosis. miR-615-5p sponge effectively alleviated disease progression and promoted remyelination. This study identifies miR-615-5p/MYRF as a new target for the therapy of demyelinating diseases.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Exosomas , MicroARNs , Vaina de Mielina , Animales , Ratones , Exosomas/metabolismo , Microglía/metabolismo , MicroARNs/genética
15.
Small ; 20(28): e2310642, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38708896

RESUMEN

Neutral electrolysis to produce hydrogen is prime challenging owing to the sluggish kinetics of water dissociation for the electrochemical reduction of water to molecular hydrogen. An ion-enriched electrode/electrolyte interface for electrocatalytic reactions can efficiently obtain a stable electrolysis system. Herein, we found that interfacial accumulated fluoride ions and the anchored Pt single atoms/nanoparticles in catalysts can improve hydrogen evolution reaction (HER) activity of NiFe-based hydroxide catalysts, prolonging the operating stability at high current density in neutral conditions. NiFe hydroxide electrode obtains an outstanding performance of 1000 mA cm-2 at low overpotential of 218 mV with 1000 h operation at 100 mA cm-2. Electrochemical experiments and theoretical calculations have demonstrated that the interfacial fluoride contributes to promote the adsorption of Pt to proton for sustaining a large current density at low potential, while the Pt single atoms/nanoparticles provide H adsorption sites. The synergy effect of F and Pt species promotes the formation of Pt─H and F─H bonds, which accelerate the adsorption and dissociation process of H2O and promote the HER reaction with a long-term durability in neutral conditions.

16.
Small ; 20(22): e2309107, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38145322

RESUMEN

Synthesis of upconversion nanoparticles (UCNPs)-metal halide perovskites (MHPs) heterostructure is garnered immense attentions due to their unparalleled photophysical properties. However, the obvious difference in their structural forms makes it a huge challenge. Herein, hexagonal ß-NaYF4 and hexagonal Cs4PbBr6 are filtrated to construct the UCNP/MHP heterostructural luminescent material. The similarity in their crystal structures facilitate the heteroepitaxial growth of Cs4PbBr6 on the surface of ß-NaYF4 NPs, leading to the formation of high-quality ß-NaYF4:Yb,Tm/Cs4PbBr6 core/shell nanocrystals (NCs). Interestingly, this heterostructure endows the core/shell NCs with typically narrow-band green emission centered at 524 nm under 980 nm excitation, which should be attributed to the Förster resonance energy transfer (FRET) from Tm3+ to Cs4PbBr6. It is noteworthy that the FRET efficiency of ß-NaYF4:Yb,Tm/Cs4PbBr6 core/shell NCs (58.33%) is much higher than that of the physically mixed sample (1.84%). In addition, the reduced defect density, lattice anchoring effect, as well as diluted ionic bonding proportion induced by the core/shell structure further increase the excellent water-resistance and thermal cycling stability of Cs4PbBr6. These findings open up a new way to construct UCNP/MHP heterostructure with better multi-code luminescence performance and stability and promote its wide optoelectronic applications.

17.
Small ; : e2311821, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38597689

RESUMEN

Lithium-air battery (LAB) is regarded as one of the most promising energy storage systems. However, the challenges arising from the lithium metal anode have significantly impeded the progress of LAB development. In this study, cellulose-based filter paper (FP) is utilized as a separator for ambient Li-air batteries to suppress dendrite growth and prevent H2O crossover. Thermogravimetric analysis and molecular spectrum reveal that FP enables ambient Li-air battery operation due to its surface functional groups derived from cellulose. The oxygen-enriched surface of cellulose not only enhances ion conductivity but also captures water and confines solvent molecules, thereby mitigating anode corrosion and side reactions. Compared with commercial glassfiber (GF) separator, this cellulose-based FP separator is cheaper, renewable, and environmentally friendly. Moreover, it requires less electrolyte while achieving prolonged and stable cycle life under real air environment conditions. This work presents a novel approach to realizing practical Li-air batteries by capturing water on the separator's surface. It also provides insights into the exploration and design of separators for enabling practical Li-air batteries toward their commercialization.

18.
Chembiochem ; : e202400339, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38801661

RESUMEN

Utilizing covalent organic frameworks (COFs) as porous supports to encapsulate enzyme represents an advanced strategy for constructing COFs biocatalysts, which has inspired numerous interests across various applications. As the structural advantages including ultrastable covalent-bonded linkage, tailorable pore structure, and metal-free biocompatibility, the resultant enzyme-COFs biocatalysts showcase functional enhancement in catalytic activity, chemical stability, long-term durability, and recyclability. This Concept describes the recent advances in the methodological strategies for engineering the COFs biocatalysts, with specific emphasis on the pore entrapment and in situ encapsulation strategies. The structural advantages of the COFs hybrid biocatalysts for organic synthesis, environment- and energy-associated applications are also canvassed. Additionally, the remaining challenges and the forward-looking directions in this field are also discussed. We believe that this Concept can offer useful methodological guidance for developing active and robust COFs biocatalysts.

19.
Mol Carcinog ; 63(3): 479-493, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38174862

RESUMEN

Cancer-associated fibroblasts (CAFs) represent a major cellular component of the tumor (pre-)metastatic niche and play an essential role in omental dissemination of ovarian cancer. The omentum is rich in adipose, and adipose-derived mesenchymal stem cells (ADSCs) have been identified as a source of CAFs. However, the molecular events driving the phenotype shift of ADSCs remain largely unexplored. In this research, we focus on integrins, transmembrane receptors that have been widely involved in cellular plasticity. We found that integrin α7 (ITGA7) was the only member of the integrin family that positively correlated with both overall survival and progression-free survival in ovarian cancer through GEPIA2. The immunohistochemistry signal of ITGA7 was apparent in the tumor stroma, and a lower omental ITGA7 level was associated with metastasis. Primary ADSCs were isolated from the omentum of patients with ovarian cancer and identified by cellular morphology, biomarkers, and multilineage differentiation. The conditional medium of ovarian cancer cells induced ITGA7 expression decrease and phenotypic changes in ADSCs. Downregulation of ITGA7 in primary omental ADSCs led to decrease in stemness properties and emerge of characteristic morphology and biomarkers of CAFs. Moreover, the conditioned medium of ADSCs with ITGA7 depletion exhibited enhanced abilities to improve the migration and invasion of ovarian cancer cells in vitro. Overall, these findings indicate that loss of ITGA7 may induce the differentiation of ADSCs to CAFs that contribute to a tumor-supportive niche.


Asunto(s)
Antígenos CD , Fibroblastos Asociados al Cáncer , Cadenas alfa de Integrinas , Integrinas , Células Madre Mesenquimatosas , Neoplasias Ováricas , Femenino , Humanos , Fibroblastos Asociados al Cáncer/patología , Proliferación Celular , Células Madre Mesenquimatosas/metabolismo , Biomarcadores , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Tejido Adiposo/metabolismo
20.
Bioinformatics ; 39(12)2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-38065693

RESUMEN

MOTIVATION: Cancer is caused by the accumulation of somatic mutations in multiple pathways, in which driver mutations are typically of the properties of high coverage and high exclusivity in patients. Identifying cancer driver genes has a pivotal role in understanding the mechanisms of oncogenesis and treatment. RESULTS: Here, we introduced MaxCLK, an algorithm for identifying cancer driver genes, which was developed by an integrated analysis of somatic mutation data and protein-protein interaction (PPI) networks and further improved by an information entropy index. Tested on pancancer and single cancers, MaxCLK outperformed other existing methods with higher accuracy. About pancancer, we predicted 154 driver genes and 787 driver modules. The analysis of co-occurrence and exclusivity between modules and pathways reveals the correlation of their combinations. Overall, our study has deepened the understanding of driver mechanism in PPI topology and found novel driver genes. AVAILABILITY AND IMPLEMENTATION: The source codes for MaxCLK are freely available at https://github.com/ShandongUniversityMasterMa/MaxCLK-main.


Asunto(s)
Biología Computacional , Neoplasias , Humanos , Entropía , Biología Computacional/métodos , Mutación , Redes Reguladoras de Genes , Neoplasias/genética , Algoritmos
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