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1.
Sci Total Environ ; 934: 173112, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38734090

RESUMO

Fenton reaction has been widely used for efficient treatment of organic wastewater. However, its applications are limited by such key factors as pH < 3. In this study, we developed, tested, and optimized an alginate/C3N4porphyrin bead (C3N4por-SA) as a recyclable photocatalyst in a photocatalysis-self-Fenton process to overcome these limitations. Porphyrin-modified C3N4 (C3N4por) was used as the H2O2 donator, while Fe(III) nodes served as the Fenton reagent. The as-prepared floating alginate/C3N4por bead utilized the light source as a driving force for the catalysis. Under visible light irradiation for 6 h, the model pollutant atrazine was degraded by 70.96 % by the optimized photocatalyst (named as C3N4por-SA-Fe1Ca5), demonstrating better photocatalytic performance than alginate/C3N4 beads. This improvement was attributed to the higher H2O2 yield from C3N4por. The alginate/C3N4por bead showed better photocatalytic activity even after several consecutive cycles and could easily be recovered for reuse. Furthermore, Fe(III)/Ca(II) bimetallic alginate bead exhibited better photocatalytic activity and a higher content of •OH radicals than the Ca(II) monometallic alginate beads, due to the ability of Fe(III) nodes to serve as a Fenton reagent. The influences of light sources, and commonly existing matters (namely SO42-, Cl-, CO32-, NO3-, and humic acid) were investigated. Moreover, the alginate/C3N4por bead demonstrated good photocatalytic performance in a simulated natural environment without the addition of extra H2O2, with an atrazine removal percentage of up to 96.3 % after 3-h irradiation. These findings indicated the great potential of alginate/C3N4por bead in practical applications.

2.
Nano Lett ; 24(10): 3221-3230, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38416582

RESUMO

The hydrolysis of hydrides, represented by MgH2, delivers substantial capacity and presents an appealing prospect for an on-site hydrogen supply. However, the sluggish hydrolysis kinetics and low hydrogen yield of MgH2 caused by the formation of a passivation Mg(OH)2 layer hinder its practical application. Herein, we present a dual strategy encompassing microstructural design and compounding, leading to the successful synthesis of a core-shell-like nanostructured MgH2@Mg(BH4)2 composite, which demonstrates excellent hydrolysis performance. Specifically, the optimal composite with a low Ea of 9.05 kJ mol-1 releases 2027.7 mL g-1 H2 in 60 min, and its hydrolysis rate escalates to 1356.7 mL g-1 min-1 H2 during the first minute at room temperature. The nanocoating Mg(BH4)2 plays a key role in enhancing the hydrolysis kinetics through the release of heat and the formation of local concentration of Mg2+ field after its hydrolysis. This work offers an innovative concept for the design of hydrolysis materials.

3.
Circulation ; 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38214194

RESUMO

BACKGROUND: Pulmonary hypertension, characterized by vascular remodeling, currently lacks curative therapeutic options. The dysfunction of pulmonary artery endothelial cells plays a pivotal role in the initiation and progression of pulmonary hypertension (PH). ErbB3 (human epidermal growth factor receptor 3), also recognized as HER3, is a member of the ErbB family of receptor tyrosine kinases. METHODS: Microarray, immunofluorescence, and Western blotting analyses were conducted to investigate the pathological role of ErbB3. Blood samples were collected for biomarker examination from healthy donors or patients with hypoxic PH. The pathological functions of ErbB3 were further validated in rodents subjected to chronic hypoxia- and Sugen-induced PH, with or without adeno-associated virus-mediated ErbB3 overexpression, systemic deletion, or endothelial cell-specific ErbB3 knockdown. Primary human pulmonary artery endothelial cells and pulmonary artery smooth muscle cells were used to elucidate the underlying mechanisms. RESULTS: ErbB3 exhibited significant upregulation in the serum, lungs, distal pulmonary arteries, and pulmonary artery endothelial cells isolated from patients with PH compared with those from healthy donors. ErbB3 overexpression stimulated hypoxia-induced endothelial cell proliferation, exacerbated pulmonary artery remodeling, elevated systolic pressure in the right ventricle, and promoted right ventricular hypertrophy in murine models of PH. Conversely, systemic deletion or endothelial cell-specific knockout of ErbB3 yielded opposite effects. Coimmunoprecipitation and proteomic analysis identified YB-1 (Y-box binding protein 1) as a downstream target of ErbB3. ErbB3 induced nuclear translocation of YB-1 and subsequently promoted hypoxia-inducible factor 1/2α transcription. A positive loop involving ErbB3-periostin-hypoxia-inducible factor 1/2α was identified to mediate the progressive development of this disease. MM-121, a human anti-ErbB3 monoclonal antibody, exhibited both preventive and therapeutic effects against hypoxia-induced PH. CONCLUSIONS: Our study reveals, for the first time, that ErbB3 serves as a novel biomarker and a promising target for the treatment of PH.

4.
Inorg Chem ; 63(1): 689-705, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38146716

RESUMO

Biomolecules play a vital role in the regulation of biomineralization. However, the characteristics of practical nucleation domains are still sketchy. Herein, the effects of the representative biomolecular sequence and conformations on calcium phosphate (Ca-P) nucleation and mineralization are investigated. The results of computer simulations and experiments prove that the line in the arrangement of dual acidic/essential amino acids with a single interval (Bc (Basic) -N (Neutral) -Bc-N-Ac (Acidic)- NN-Ac-N) is most conducive to the nucleation. 2α-helix conformation can best induce Ca-P ion cluster formation and nucleation. "Ac- × × × -Bc" sequences with α-helix are found to be the features of efficient nucleation domains, in which process, molecular recognition plays a non-negligible role. It further indicates that the sequence determines the potential of nucleation/mineralization of biomolecules, and conformation determines the ability of that during functional execution. The findings will guide the synthesis of biomimetic mineralized materials with improved performance for bone repair.


Assuntos
Biomineralização , Fosfatos de Cálcio , Fosfatos de Cálcio/química , Conformação Molecular
5.
Acta Pharm Sin B ; 13(12): 4840-4855, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38045055

RESUMO

Pulmonary hypertension (PH) is an extremely malignant pulmonary vascular disease of unknown etiology. ADAR1 is an RNA editing enzyme that converts adenosine in RNA to inosine, thereby affecting RNA expression. However, the role of ADAR1 in PH development remains unclear. In the present study, we investigated the biological role and molecular mechanism of ADAR1 in PH pulmonary vascular remodeling. Overexpression of ADAR1 aggravated PH progression and promoted the proliferation of pulmonary artery smooth muscle cells (PASMCs). Conversely, inhibition of ADAR1 produced opposite effects. High-throughput whole transcriptome sequencing showed that ADAR1 was an important regulator of circRNAs in PH. CircCDK17 level was significantly lowered in the serum of PH patients. The effects of ADAR1 on cell cycle progression and proliferation were mediated by circCDK17. ADAR1 affects the stability of circCDK17 by mediating A-to-I modification at the A5 and A293 sites of circCDK17 to prevent it from m1A modification. We demonstrate for the first time that ADAR1 contributes to the PH development, at least partially, through m1A modification of circCDK17 and the subsequent PASMCs proliferation. Our study provides a novel therapeutic strategy for treatment of PH and the evidence for circCDK17 as a potential novel marker for the diagnosis of this disease.

6.
Langmuir ; 39(48): 17378-17391, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37975653

RESUMO

Increasingly, oil spills and industrial discharges are wreaking havoc on the water environment; in order to efficiently separate oil and water from sewage containing oil or organic solvents, a novel porous polymer (P(EHA-co-BA)) was prepared by Pickering high internal phase emulsion (HIPE) template method. To obtain polyHIPE with better oil/water separation capacities, octadecyltrichlorosilane (OTS)-modified carbon nanotubes (CNTs) and surfactants were used as costabilizers for HIPE, which improved the stability of HIPE as well as the mechanical properties and the separation efficiency of polyHIPE. In the presence of 1 wt % OTS-CNT adding in the oil phase, 1%OTS-CNT polyHIPE has high porosity (92.21%), favorable hydrophobicity (a water contact angle of 128°), and excellent mechanical properties. As a result, 1%OTS-CNT polyHIPE has high absorption of oils and oily solvents, e.g., dichloromethane up to 36 g/g, and maintains an absorption efficiency of >97% after 20 reapplications. In the formulation of polyHIPE, cinnamaldehyde (CA) has been added to provide superior antibacterial properties against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). It appears that the novel polyHIPE proposed in this work is a reusable antibacterial porous polymer with promising applications for oil-water separation.

7.
Life Sci ; 334: 122217, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37925140

RESUMO

AIMS: Diabetic retinopathy (DR) is a common microvascular complication of diabetes mellitus and one of the major causes of visual impairment and blindness in industrialized countries. The early neuro-glial perturbations, especially retinal Müller cells (rMC) activation, intimately associated with the vascular alterations. MicroRNAs (miRNAs) have been reported to play critical roles in the progression of DR. Here, we aimed to further explore the role and underlying mechanism of miR-423-5p in Müller cell activation in streptozotocin (STZ)-induced diabetic mice and oxygen-induced retinopathy (OIR) model. MATERIALS AND METHODS: Retinal histology, optical coherence tomography (OCT) and biochemical markers were assessed. KEY FINDINGS: Our data revealed that the expression of miR-423-5p was significantly increased under high-glucose environment. We also demonstrated that miR-423-5p overexpression markedly accelerated retinal vascular leakage, leukocytosis, and rMC activation. This response was ameliorated in animals pre-treated with the inhibition of miR-423-5p. Specifically, miR-423-5p bound to the nerve growth factor (NGF) 3' UTR region to induce its silencing. NGF inhibition significantly promoted retinal microvascular dysfunction. SIGNIFICANCE: These findings demonstrate that miR-423-5p is a critical miRNA that promotes microvascular dysfunction in DR.


Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , MicroRNAs , Camundongos , Animais , Retinopatia Diabética/metabolismo , Células Ependimogliais/metabolismo , Fator de Crescimento Neural , Diabetes Mellitus Experimental/patologia , MicroRNAs/genética , MicroRNAs/metabolismo
8.
Nano Lett ; 23(23): 11288-11296, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-37983011

RESUMO

Core-shell crystalline-amorphous nanocomposites, featuring nanograins surrounded by thick amorphous boundaries, are promising nanoarchitectures for achieving exceptional strength through cooperative strengthening effects. However, a comprehensive understanding of the influence of characteristic sizes, particularly the amorphous thickness, on codeformation strengthening is still lacking, limiting the attainment of the strength limit. Here, we employ molecular dynamics simulations to investigate Cu-CuTa crystalline-amorphous nanocomposites with varying grain sizes and amorphous thicknesses. Our findings demonstrate significant strengthening effects in nanocomposites, effectively suppressing the Hall-Petch breakdown observed in traditional amorphous-free nanograined Cu. Intriguingly, we observe a maximum strength followed by a strengthening-softening transition dependent on the amorphous thickness, as exemplified by a representative nanocomposite featuring a 12.5 nm grain size and a critical amorphous thickness of 4 nm. Inspired by observed shifts in atomistic mechanisms, we developed a theoretical model encompassing variations in grain size and amorphous thickness, providing valuable insights into the size-strength relationship for crystalline-amorphous nanocomposites.

9.
ACS Appl Mater Interfaces ; 15(41): 48277-48286, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37801021

RESUMO

Mn-based layered oxides have been considered the most promising cathode candidates for cost-effective potassium-ion batteries (PIBs). Herein, equiatomic constituents of Ni, Fe, Mg, and Ti have been introduced into the transition metal layers of Mn-based layered oxide to design a high-entropy K0.6Ni0.05Fe0.05Mg0.05Ti0.05Mn0.0725O2 (HE-KMO, S = 1.17R). Consequently, the experimental results manifest that the layered structure of HE-KMO is more stable than conventional low-entropy K0.6MnO2 (LE-KMO, S = 0.66R) during successive cycling and even upon exposure to moisture. Diffraction and electrochemical measurements reveal that HE-KMO undergoes a solid-solution mechanism, contrary to the multistage phase transition processes typically exemplified in K0.6MnO2. Benefiting from the stabilized high-entropy layered framework and the solid-solution K+ storage mechanism, the entropy-stabilized HE-KMO not only demonstrates exceptional rate capability but also shows excellent cyclic stability. Notably, a capacity retention ratio of 86% after 3000 cycles can still be sustained at a remarkable current density of 5000 mA g-1.

10.
iScience ; 26(7): 107003, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37534137

RESUMO

TP53 mutations are ubiquitous with tumorigenesis in non-small cell lung cancers (NSCLC). By analyzing the TCGA database, we reported that TP53 missense mutations are correlated with chromosomal instability and tumor mutation burden in NSCLC. The inability of wild-type nor mutant p53 expression can't predict survival in lung cancer cohorts, however, an examination of primary NSCLC tissues found that acetylated p53 did yield an association with improved survival outcomes. Molecularly, we demonstrated that acetylation drove the ubiquitination and degradation of mutant p53 but enhanced stability of wild-type p53. Moreover, acetylation of a missense p53 mutation prevented the gain of oncogenic function observed in typical TP53 mutant-expressing cells and enhanced tumor suppressor functions. Consequently, acetylation inducer targeting of missense mutant p53 may be a viable therapeutic goal for NSCLC treatment and may improve the accuracy of current efforts to utilize p53 mutations in a prognostic manner.

11.
Environ Res ; 236(Pt 2): 116685, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37467944

RESUMO

Metal organic frameworks (MOFs) have demonstrated great potential for their favorable impacts on the performance of water treatment membranes. Herein, the novel nanoparticles based on both nanoporous MOFs and organic PDA layer was exploited as a novel dopant for the fabrication of PES ultrafiltration (UF) membranes. The PDA was synthesized via oxidative self-polymerization under alkaline conditions and formed adhesive coatings on dispersed MOF. The properties of resulting membranes on the porosity, membrane morphology, hydrophilicity, permeability and anti-fouling performance were adequately investigated. The membranes incorporated with MOF@PDA exhibited exceptionally high permeability (209.02 L m-2·h-1), which is approximately 6 times higher than that of the pure PES membrane, and high BSA rejection (99.12%). Notably, the mechanical property and hydrophilicity of the PES membrane were both enhanced by MOF@PDA, and it has been demonstrated that greater hydrophilicity prevents fouling under practical conditions, which results in significant improvements in flux recovery ratio (FRR) (82%). In addition, the modified PES membranes were used to purify the oil/water emulsion, and the results indicates that the membranes have high permeability and rejection of oil/water emulsion, showing its great promise in practical oily sewage remediation.

12.
Chemosphere ; 334: 138998, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37211167

RESUMO

The demand for efficient wastewater treatment is becoming increasingly urgent due to the rising threat of pharmaceutical residues in water. As a sustainable advanced oxidation process, cold plasma technology is a promising approach for water treatment. However, the adoption of the technology encounters several challenges, including the low treatment efficiency and the potentially unknown environmental impact. Here, microbubble generation was integrated with cold plasma system to enhance treatment of wastewater contaminated with diclofenac (DCF). The degradation efficiency depended on the discharge voltage, gas flow, initial concentration, and pH value. The best degradation efficiency was 90.9% after 45 min plasma-bubble treatment under the optimum process parameters. The hybrid plasma-bubble system exhibited strongly synergistic performance heralded by up to seven-times higher DCF removal rates than the two systems operated separately. The plasma-bubble treatment remains effective even after addition of SO42-, Cl-, CO32-, HCO3-, and humic acid (HA) as interfering background substances. The contributions of •O2-, O3, •OH, and H2O2 reactive species to the DCF degradation process were specified. The synergistic mechanisms for DCF degradation were deduced through the analysis of the degradation intermediates. Further, the plasma-bubble treated water was proven safe and effective to stimulate seed germination and plant growth for sustainable agriculture applications. Overall, these findings provide new insights and a feasible approach with a highly synergistic removal effect for the plasma-enhanced microbubble wastewater treatment, without generating secondary contaminants.


Assuntos
Gases em Plasma , Poluentes Químicos da Água , Águas Residuárias , Diclofenaco/química , Microbolhas , Peróxido de Hidrogênio/química , Gases em Plasma/análise , Poluentes Químicos da Água/análise , Agricultura
13.
Lung ; 201(2): 235-242, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36823409

RESUMO

PURPOSE: Idiopathic pulmonary fibrosis (IPF) is a chronic progressive interstitial lung disease characterized by excessive extracellular matrix deposition. No effective treatments are currently available for IPF. High-temperature requirement A3 (HtrA3) suppresses tumor development by antagonizing transforming growth factor ß (TGF-ß) signaling; however, little is known about the role of HtrA3 in IPF. This study investigated the role of HtrA3 in IPF and underlying mechanisms. METHODS: Lung tissues were collected from patients with IPF and mice with bleomycin (BLM)-induced pulmonary fibrosis, and HtrA3 expression was measured in tissue samples. Then, HtrA3 gene knockout mice were treated with BLM to induce pulmonary fibrosis and explore the effects and underlying mechanism of HtrA3 on pulmonary fibrosis. RESULTS: HtrA3 was up-regulated in the lung tissues of patients with IPF and the pulmonary fibrotic mouse model compared to corresponding control groups. HtrA3 knockout decreased pulmonary fibrosis-related protein expression, alleviated the symptoms of pulmonary fibrosis, and inhibited epithelial-mesenchymal transition (EMT) in BLM-induced lung tissue compared with BLM-induced wild-type mice. The TGF-ß1/Smad signaling pathway was activated in fibrotic lung tissue, whereas HtrA3 knockout inhibited this pathway. CONCLUSION: The expression level of HtrA3 is increased in fibrotic lungs. HtrA3 knockout alleviates the symptoms of pulmonary fibrosis probably via the TGF-ß1/Smad signaling pathway. Therefore, HtrA3 inhibition is a potential therapeutic target for pulmonary fibrosis.


Assuntos
Fibrose Pulmonar Idiopática , Doenças Pulmonares Intersticiais , Animais , Camundongos , Bleomicina/metabolismo , Bleomicina/farmacologia , Transição Epitelial-Mesenquimal , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/patologia , Doenças Pulmonares Intersticiais/patologia , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo
14.
Clin Transl Med ; 12(9): e1042, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36116131

RESUMO

BACKGROUND: NF-κB signaling is widely linked to the pathogenesis and treatment resistance in cancers. Increasing attention has been paid to its anti-oncogenic roles, due to its key functions in cellular senescence and the senescence-associated secretory phenotype (SASP). Therefore, thoroughly understanding the function and regulation of NF-κB in cancers is necessary prior to the application of NF-κB inhibitors. METHODS: We established glioblastoma (GBM) cell lines expressing ectopic TCF4N, an isoform of the ß-catenin interacting transcription factor TCF7L2, and evaluated its functions in GBM tumorigenesis and chemotherapy in vitro and in vivo. In p65 knock-out or phosphorylation mimic (S536D) cell lines, the dual role and correlation of TCF4N and NF-κB signaling in promoting tumorigenesis and chemosensitivity was investigated by in vitro and in vivo functional experiments. RNA-seq and computational analysis, immunoprecipitation and ubiquitination assay, minigene splicing assay and luciferase reporter assay were performed to identify the underlying mechanism of positive feedback regulation loop between TCF4N and the p65 subunit of NF-κB. A eukaryotic cell-penetrating peptide targeting TCF4N, 4N, was used to confirm the therapeutic significance. RESULTS: Our results indicated that p65 subunit phosphorylation at Ser 536 (S536) and nuclear accumulation was a promising prognostic marker for GBM, and endowed the dual functions of NF-κB in promoting tumorigenesis and chemosensitivity. p65 S536 phosphorylation and nuclear stability in GBM was regulated by TCF4N. TCF4N bound p65, induced p65 phosphorylation and nuclear translocation, inhibited its ubiquitination/degradation, and subsequently promoted NF-κB activity. p65 S536 phosphorylation was essential for TCF4N-led senescence-independent SASP, GBM tumorigenesis, tumor stem-like cell differentiation and chemosensitivity. Activation of p65 was closely connected to alterative splicing of TCF4N, a likely positive feedback regulation loop between TCF4N and p65 in GBM. 4N increased chemosensitivity, highlighting a novel anti-cancer strategy. CONCLUSION: Our study defined key roles of TCF4N as a novel regulator of NF-κB through mutual regulation with p65 and provided a new avenue for GBM inhibition.


Assuntos
Neoplasias do Sistema Nervoso Central , Glioblastoma , Proteína 2 Semelhante ao Fator 7 de Transcrição , Fator de Transcrição RelA , Carcinogênese/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Peptídeos Penetradores de Células , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Neoplasias do Sistema Nervoso Central/genética , Neoplasias do Sistema Nervoso Central/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Resistencia a Medicamentos Antineoplásicos/fisiologia , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Luciferases , NF-kappa B/genética , NF-kappa B/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , beta Catenina
15.
Adv Sci (Weinh) ; 9(26): e2200169, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35843865

RESUMO

Sustained activation of signal transducer and activator of transcription 3 (STAT3) is a critical contributor in tumorigenesis and chemoresistance, thus making it an attractive cancer therapeutic target. Here, SH2 domain-containing adapter protein F (SHF) is identified as a tumor suppressor in glioblastoma Multiforme (GBM) and its negative regulation of STAT3 activity is characterized. Mechanically, SHF selectively binds and inhibits acetylated STAT3 dimerization without affecting STAT3 phosphorylation or acetylation. Additionally, by blocking STAT3-DNMT1 (DNA Methyltransferase 1) interaction, SHF relieves methylation of tumor suppressor genes. The SH2 domain is documented to be essential for SHF's actions on STAT3, and almost entirely replaces the functions of SHF on STAT3 independently. Moreover, the peptide C16 a peptide derived from the STAT3-binding sites of SHF inhibits STAT3 dimerization and STAT3/DNMT1 interaction, and achieves remarkable growth inhibition in GBM cells in vitro and in vivo. These findings strongly identify targeting of the SHF/STAT3 interaction as a promising strategy for developing an optimal STAT3 inhibitor and provide early evidence of the potential clinical efficacy of STAT3 inhibitors such as C16 in GBM.


Assuntos
Glioblastoma , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Dimerização , Genes Supressores de Tumor , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Fosforilação , Multimerização Proteica , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
16.
Chem Sci ; 13(20): 5920-5928, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35685796

RESUMO

Subnanometer single-chirality single-walled carbon nanotubes (SWCNTs) are of particular interest in multiple applications. Inspired by the interdisciplinary combination of redox active polyoxometalates and SWCNTs, here we report a cluster steric hindrance strategy by assembling polyoxometalates on the outer surface of subnanometer SWCNTs via electron transfer and demonstrate the selective separation of monochiral (6,5) SWCNTs with a diameter of 0.75 nm by a commercially available conjugated polymer. The combined use of DFT calculations, TEM, and XPS unveils the mechanism that selective separation is associated with tube diameter-dependent interactions between the tube and clusters. Sonication drives the preferential detachment of polyoxometalate clusters from small-diameter (6,5) SWCNTs, attributable to weak tube-cluster interactions, which enables the polymer wrapping and separation of the released SWCNTs, while strong binding clusters with large-diameter SWCNTs provide steric hindrance and block the polymer wrapping. The polyoxometalate-assisted modulation, which can be rationally customized, provides a universal and robust pathway for the separation of SWCNTs.

17.
Sci Adv ; 8(25): eabo4599, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35731880

RESUMO

Intermetallic catalysts are of immense interest, but how heterometals diffuse and related interface structure remain unclear when there exists a strong metal-support interaction. Here, we developed a kinetic diffusion-controlled method and synthesized intermetallic Pt2Mo nanocrystals with twin boundaries on mesoporous carbon (Pt2Mo/C). The formation of small-sized twinned intermetallic nanocrystals is associated with the strong Mo-C interaction-induced slow Mo diffusion and the heterogeneity of alloying, which is revealed by an in situ aberration-corrected transmission electron microscope (TEM) at high temperature. The twinned Pt2Mo/C constitutes a promising CO-resistant catalyst for highly selective hydrogenation of nitroarenes. Theoretical calculations and environmental TEM suggest that the weakened CO adsorption over Pt sites of Pt2Mo twin boundaries and their local region endows them with high CO resistance, selectivity, and reusability. The present strategy paves the way for tailoring the interface structure of high-melting point Mo/W-based intermetallic nanocrystals that proved to be important for the industrially viable reactions.

18.
Genes (Basel) ; 13(4)2022 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-35456381

RESUMO

We used genotyping-by-sequencing (GBS) to identify sex-linked markers in 43 wild-collected spiny frog (Quasipaa boulengeri) adults from a single site. We identified a total of 1049 putatively sex-linked GBS-tags, 98% of which indicated an XX/XY system, and finally confirmed 574 XY-type sex-linked loci. The sex specificity of five markers was further validated by PCR amplification using a large number of additional individuals from 26 populations of this species. A total of 27 sex linkage markers matched with the Dmrt1 gene, showing a conserved role in sex determination and differentiation in different organisms from flies and nematodes to mammals. Chromosome 1, which harbors Dmrt1, was considered as the most likely candidate sex chromosome in anurans. Five sex-linked SNP makers indicated sex reversals, which are sparsely present in wild amphibian populations, in three out of the one-hundred and thirty-three explored individuals. The variety of sex-linked markers identified could be used in population genetics analyses requiring information on individual sex or in investigations aimed at drawing inferences about sex determination and sex chromosome evolution.


Assuntos
Ranidae , Cromossomos Sexuais , Animais , Anuros/genética , Ligação Genética , Genótipo , Mamíferos/genética , Ranidae/genética , Cromossomos Sexuais/genética
19.
Nanoscale ; 14(3): 953-961, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34989359

RESUMO

The selective separation of soluble and individual single-walled carbon nanotubes (SWCNTs) in aqueous solution is a key step for harnessing the extraordinary properties of these materials. Manipulating the strong van der Waals intertube interactions between the SWCNT bundles is very important in selective separation, which is a long-standing challenge. Here we reported the ability of redox polyoxometalate clusters to modulate the intertube π-π stacking interaction through electron transfer and achieved the diameter-selective separation of SWCNTs in a surfactant aqueous solution. The large-diameter SWCNTs concentrated at ∼1.3-1.4 nm were selectively separated when ∼1 nm clusters encapsulated within the tube cavity, and the dispersion of subnanometer ∼0.7-0.9 nm SWCNTs was boosted when clusters were adsorbed on the outer surface of small-diameter nanotubes. The mechanism of diameter-selective separation of SWCNTs associated with the size-dependent interaction between cluster-tubes and the steric hindrance effect of clusters was revealed by optical absorption and Raman spectroscopy. This simple method thus enables the selective separation of individual high-quality SWCNTs in aqueous solutions without harsh sonication with the potential for other separation applications.

20.
FEBS J ; 289(7): 1968-1983, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34741776

RESUMO

Retinal pigment epithelium (RPE) cell damage is implicated in the pathogenesis of age-related macular degeneration (AMD). An increase of interferon-γ (IFN-γ) levels was observed in patients with AMD, but whether inflammatory factors are causally related to AMD progression is unclear. Here, we demonstrate a direct causal relationship between IFN-γ and RPE cell death. IFN-γ induced human retinal pigment epithelial cell (ARPE-19) death accompanied by increases in Fe2+ , reactive oxygen species, lipid peroxidation, and glutathione (GSH) depletion, which are main characteristics of ferroptosis. Mechanistically, IFN-γ upregulates the level of intracellular Fe2+ through inhibiting Fe2+ efflux protein SLC40A1 and induces GSH depletion by blocking cystine/glutamate antiporter, System xc-. At the same time, treatment with IFN-γ decreases the level of glutathione peroxidase 4 (GPx4), rendering the cells more sensitive to ferroptosis. JAK1/2 and STAT1 inhibitors could reverse the reduction of SLC7A11, GPx4 and GSH expression induced by IFN-γ, indicating IFN-γ induces ARPE-19 cell ferroptosis via activation of the JAK1-2/STAT1/SLC7A11 signaling pathway. The above results were largely confirmed in IFN-γ-treated mice in vivo. Finally, we used sodium iodate (NaIO3 )-induced retinal degeneration to further explore the role of ferroptosis in AMD in vivo. Consistent with the role of IFN-γ, treatment with NaIO3 decreased SLC7A11, GPx4 and SLC40A1 expressions. NaIO3 -induced RPE damage was accompanied by increased iron, lipid peroxidation products (4-hydroxynonenal, malondialdehyde), and GSH depletion, and ferroptosis inhibitors could reverse the above phenomenon. Taken together, our findings suggest that inhibiting ferroptosis or reducing IFN-γ may serve as a promising target for AMD.


Assuntos
Ferroptose , Degeneração Macular , Sistema y+ de Transporte de Aminoácidos/genética , Sistema y+ de Transporte de Aminoácidos/metabolismo , Animais , Células Epiteliais/metabolismo , Humanos , Interferon gama/genética , Interferon gama/metabolismo , Interferon gama/farmacologia , Janus Quinase 1/metabolismo , Degeneração Macular/genética , Degeneração Macular/metabolismo , Camundongos , Estresse Oxidativo , Epitélio Pigmentado da Retina/metabolismo , Pigmentos da Retina/metabolismo , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais
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