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1.
Biomed Pharmacother ; 171: 116195, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38262149

RESUMO

Our recent study showed that Nitazoxanide (NTZ), an FDA-approved anti-parasitic drug, prevents ovariectomy-induced bone loss by inhibiting osteoclast activity. However, there have been no investigations to determine whether NTZ has preventive potential in other bone resorbing diseases, especially rheumatoid arthritis (RA). In this study, the primary RA fibroblast-like synoviocytes (RA-FLS) and collagen-induced arthritis (CIA) murine model were used to evaluate the effect of NTZ. The results showed that NTZ potently inhibited proliferation, migration and invasion capacity of RA-FLS in a dose dependent manner by restraining cell entry into S phases, without induction of cell apoptosis. NTZ obviously reduced spontaneous mRNA expression of IL-1ß, IL-6 and RANKL, as well as TNF-α-induced transcription of the IL-1ß, IL-6, and MMP9 genes. In terms of molecular mechanism, NTZ significantly inhibited the basal or TNF-α-induced activation of JAK2/STAT3 (T705) and NF-κB pathway, but not MAPK and STAT3 (S727) phosphorylation. Moreover, NTZ ameliorated synovial inflammation and bone erosion in CIA mice through reducing the production of inflammatory mediators and osteoclast formation, respectively. Collectively, our findings indicate that NTZ exhibits anti-inflammatory and anti-erosive effects both ex vivo and in vivo, which provides promising evidence for the therapeutic application of NTZ as a novel therapeutic agent for RA.


Assuntos
Artrite Experimental , Artrite Reumatoide , Nitrocompostos , Sinoviócitos , Tiazóis , Feminino , Camundongos , Animais , Sinoviócitos/metabolismo , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Inflamação/metabolismo , Fibroblastos , Células Cultivadas , Membrana Sinovial/metabolismo
2.
Noncoding RNA Res ; 8(4): 571-578, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37602319

RESUMO

Background: Breast cancer is one of the most common cancer type of women in the world. miR-301b-3p/5p were paired miRNAs derived from the same pre-miRNA, which may have different clinical roles in tumor and requires more exploration and research. Methods: In order to investigate the differential expression, clinical significance, diagnostic and prognostic value of miR-301b-3p/5p and explore their function in breast cancer, we extracted information of miRNAs from TCGA data sets for clinical correlation analysis, and the potential function was explored by GO、KEGG enrichment and immunoinfiltration analysis. Results: miR-301b-3p/5p were both highly expressed in breast cancer, there is a positive correlation between them. miR-301b-3p and miR-301b-5p have different clinical features. In breast cancer, miR-301b-3p can be used as a potential diagnostic marker while miR-301b-5p can be used as a prognostic molecule. GO, KEGG enrichment and immunoinfiltration analysis reveals that miR-301b-3p focuses on molecular functions, miR-301b-5p focuses on regulation of angiogenesis, and it is correlated with immune cells. Conclusions: miR-301b-3p and miR-301b-5p are both tumor promoter in breast cancer, miR-301b-3p can be used as a potential diagnostic marker, while miR-301b-5p can be used as a prognostic molecule and an underlying therapy target. Although miR-301b-3p/5p is a pair of miRNAs from two arms of the same pre-miRNA, they may promote the progression of breast cancer together through different pathway.

3.
Angew Chem Int Ed Engl ; 62(42): e202310733, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37642552

RESUMO

Photocatalytic conversion of low-concentration CO2 is considered as a promising way to simultaneously mitigate the environmental and energy issues. However, the weak CO2 adsorption and tough CO2 activation process seriously compromise the CO production, due to the chemical inertness of CO2 molecule and the formed fragile metal-C/O bond. Herein, we designed and fabricated oxygen vacancy contained Co3 O4 hollow nanoparticles on ordered macroporous N-doped carbon framework (Vo-HCo3 O4 /OMNC) towards photoreduction of low-concentration CO2 . In situ spectra and ab initio molecular dynamics simulations reveal that the constructed oxygen vacancy is able to break the local structural symmetry of Co-O-Co sites. The formation of asymmetric active site switches the CO2 configuration from a single-site linear model to a multiple-sites bending one with a highly stable configuration, enhancing the binding and structural polarization of CO2 molecules. As a result, Vo-HCo3 O4 /OMNC shows unprecedent activity in the photocatalytic conversion of low-concentration CO2 (10 % CO2 /Ar) under laboratory light source or even natural sunlight, affording a syngas yield of 337.8 or 95.2 mmol g-1 h-1 , respectively, with an apparent quantum yield up to 4.2 %.

4.
Small ; 19(43): e2304053, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37357174

RESUMO

Oxidation reaction is of critical importance in chemical industry, in which the primary O2 activation step still calls for high-performance catalysts. Here, a newly developed precise locating carbonization strategy for the fabrication of 21 kinds of dual-metal single-atom catalysts with N, S co-coordinated configurations is reported. As is exemplified by CoN3 S1 /CuN4 @NC, systematical characterizations and in situ observations imply the atomic CoN3 S1 and CuN4 sites immobilized on N-doped carbon, over which the remarkable electron redistribution originating from their unsymmetrical coordination configurations. Impressively, the obtained CoN3 S1 /CuN4 @NC exhibits unprecedented capability in O2 activation and enables a spontaneous process through its dynamic configuration, significantly outperforming the CoN4 /CuN4 @NC and CoN3 S1 @NC counterparts. Hence, the CoN3 S1 /CuN4 @NC shows attractive performance in domino synthesis of natural flavone and 19 kinds of derivatives from benzyl alcohol, 2'-hydroxyacetophenone, and corresponding substituted substrates via aerobic oxidative coupling-dehydrogenation. Detailed reaction mechanisms and molecule behaviors over CoN3 S1 /CuN4 @NC are also investigated through in situ experiments and simulations.

5.
Sensors (Basel) ; 23(5)2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36904775

RESUMO

Bridges are often at risk due to the effects of natural disasters, such as earthquakes and typhoons. Bridge inspection assessments normally focus on cracks. However, numerous concrete structures with cracked surfaces are highly elevated or over water, and is not easily accessible to a bridge inspector. Furthermore, poor lighting under bridges and a complex visual background can hinder inspectors in their identification and measurement of cracks. In this study, cracks on bridge surfaces were photographed using a UAV-mounted camera. A YOLOv4 deep learning model was used to train a model for identifying cracks; the model was then employed in object detection. To perform the quantitative crack test, the images with identified cracks were first converted to grayscale images and then to binary images the using local thresholding method. Next, the two edge detection methods, Canny and morphological edge detectors were applied to the binary images to extract the edges of the cracks and obtain two types of crack edge images. Then, two scale methods, the planar marker method, and the total station measurement method, were used to calculate the actual size of the crack edge image. The results indicated that the model had an accuracy of 92%, with width measurements as precise as 0.22 mm. The proposed approach can thus enable bridge inspections and obtain objective and quantitative data.

6.
COPD ; 20(1): 44-54, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36655999

RESUMO

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease that causes obstructed airflow from the lungs. DNA methylation can regulate gene expression. Understanding the potential molecular mechanism of COPD is of great importance. The aim of this study was to find differentially methylated/expressed genes in COPD. DNA methylation and gene expression profiles in COPD were downloaded from the dataset, followed by functional analysis of differentially-methylated/expressed genes. The potential diagnostic value of these differentially-methylated/expressed genes was determined by receiver operating characteristic (ROC) analysis. Expression validation of differentially-methylated/expressed genes was performed by in vitro experiment and extra online datasets. Totally, 81 hypermethylated-low expression genes and 121 hypomethylated-high expression genes were found in COPD. Among which, 9 core hypermethylated-low expression genes (CD247, CCR7, CD5, IKZF1, SLAMF1, IL2RB, CD3E, CD7 and IL7R) and 8 core hypomethylated-high expression genes (TREM1, AQP9, CD300LF, CLEC12A, NOD2, IRAK3, NLRP3 and LYZ) were identified in the protein-protein interaction (PPI) network. Moreover, these genes had a potential diagnostic utility for COPD. Some signaling pathways were identified in COPD, including T cell receptor signaling pathway, cytokine-cytokine receptor interaction, hematopoietic cell lineage, HTLV-I infection, endocytosis and Jak-STAT signaling pathway. In conclusion, differentially-methylated/expressed genes and involved signaling pathways are likely to be associated with the process of COPD.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Humanos , Redes Reguladoras de Genes , Metilação de DNA , Mapas de Interação de Proteínas/genética , Pulmão , Perfilação da Expressão Gênica , Receptores Mitogênicos/genética , Lectinas Tipo C/genética
7.
PeerJ ; 11: e14640, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36650834

RESUMO

Background: Insufficient thermal ablation can accelerate malignant behaviors and metastases in some solid tumors, and epithelial-mesenchymal transition (EMT) and autophagy are involved in tumor metastasis. It has been found that TGF-ß2 which belongs to the family of transforming growth factors often associated with cancer cell invasiveness and EMT. However, whether the interactions between autophagy and TGF-ß2 induce EMT in breast cancer (BC) cells following insufficient microwave ablation (MWA) remains unclear. Methods: BC cells were treated with sublethal heat treatment to simulate insufficient MWA, and the effects of heat treatment on the BC cell phenotypes were explored. CCK-8, colony formation, flow cytometry, Transwell, and wound healing assays were performed to evaluate the influence of sublethal heat treatment on the proliferation, apoptosis, invasion, and migration of BC cells. Western blotting, real-time quantitative PCR, immunofluorescence, and transmission electron microscopy were carried out to determine the changes in markers associated with autophagy and EMT following sublethal heat treatment. Results: Results showed that heat treatment promoted the proliferation of surviving BC cells, which was accompanied by autophagy induction. Heat treatment-induced autophagy up-regulated TGF-ß2/Smad2 signaling and promoted EMT phenotype, thereby enhancing BC cells' migration and invasion abilities. An increase or decrease of TGF-ß2 expression resulted in the potentiation and suppression of autophagy, as well as the enhancement and abatement of EMT. Autophagy inhibitors facilitated apoptosis and repressed proliferation of BC cells in vitro, and thwarted BC cell tumor growth and pulmonary metastasis in vivo. Conclusion: Heat treatment-induced autophagy promoted invasion and metastasis via TGF-ß2/Smad2-mediated EMTs. Suppressing autophagy may be a suitable strategy for overcoming the progression and metastasis of residual BC cells following insufficient MWA.


Assuntos
Neoplasias Pulmonares , Fator de Crescimento Transformador beta2 , Humanos , Movimento Celular , Fator de Crescimento Transformador beta2/genética , Transição Epitelial-Mesenquimal , Temperatura Alta , Neoplasias Pulmonares/patologia , Invasividade Neoplásica , Autofagia/genética
8.
Angew Chem Int Ed Engl ; 62(9): e202218115, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36627240

RESUMO

It is highly desired to achieve controllable product selectivity in CO2 hydrogenation. Herein, we report light-induced switching of reaction pathways of CO2 hydrogenation towards CH3 OH production over actomically dispersed Co decorated Pt@UiO-66-NH2 . CO, being the main product in the reverse water gas shift (RWGS) pathway under thermocatalysis condition, is switched to CH3 OH via the formate pathway with the assistance of light irradiation. Impressively, the space-time yield of CH3 OH in photo-assisted thermocatalysis (1916.3 µmol gcat -1 h-1 ) is about 7.8 times higher than that without light at 240 °C and 1.5 MPa. Mechanism investigation indicates that upon light irradiation, excited UiO-66-NH2 can transfer electrons to Pt nanoparticles and Co sites, which can efficiently catalyze the critical elementary steps (i.e., CO2 -to-*HCOO conversion), thus suppressing the RWGS pathway to achieve a high CH3 OH selectivity.

9.
JACS Au ; 3(1): 185-194, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36711096

RESUMO

The regulation of coordination configurations of single-atom sites is highly desirable to boost the catalytic performances of SA catalysts. Here, we demonstrate a versatile complexation-deposition strategy for the synthesis of 13 kinds of dual-metal SA site pairs with uniform and exclusive coordination configurations. The preparation is specifically exemplified by the fabrication of Cu and Co single-atom pairs with the co-existence of N and P heteroatoms through etching and pyrolysis of a pre-synthesized metal-organic framework template. Systematic characterizations reveal the uniform and exclusive coordinative configuration of Cu and Co SA sites in CuN4/CoN3P1 and CuN4/CoN2P2, over which the electrons are unsymmetrically distributed. Impressively, the CuN4/CoN2P2 site pairs exhibit significantly enhanced catalytic activity and selectivity in the synthesis of a variety of natural flavonoids in comparison with the CuN4/CoN3P1 and CuN4/CoN4 counterparts. Theoretical calculation results suggest that the unsymmetrical electron distribution over the CuN4/CoN2P2 sites could facilitate the adsorption and disassociation of oxygen molecules via reducing the energy barriers of the generation of the key intermediates and thus kinetically accelerate the oxidative-coupling reaction process.

10.
Nat Commun ; 13(1): 7873, 2022 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-36550133

RESUMO

Single-atom (SA) catalysts provide extensive possibilities in pursuing fantastic catalytic performances, while their preparation still suffers from metal aggregation and pore collapsing during pyrolysis. Here we report a versatile medium-induced infiltration deposition strategy for the fabrication of SAs and hetero-SAs (MaN4/MbN4@NC; Ma = Cu, Co, Ni, Mn, Mb = Co, Cu, Fe, NC = N-doped carbon). In-situ and control experiments reveal that the catalyst fabrication relies on the "step-by-step" evolution of Ma-containing metal-organic framework (MOF) template and Mb-based metal precursor, during which molten salt acts as both pore generator in the MOF transformation, and carrier for the oriented infiltration and deposition of the latter to eventually yield metal SAs embedded on hierarchically porous support. The as-prepared hetero-SAs show excellent catalytic performances in the general synthesis of 33 kinds of natural flavones. The highly efficient synthesis is further strengthened by the reliable durability of the catalyst loaded in a flow reactor. Systematic characterizations and mechanism studies suggest that the superior catalytic performances of CuN4/CoN4@NC are attributed to the facilitated O2 activating-splitting process and significantly reduced reaction energy barriers over CoN4 due to the synergetic interactions of the adjacent CuN4.

11.
Allergy Asthma Clin Immunol ; 18(1): 108, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36550577

RESUMO

BACKGROUND: Asthma is an important non-communicable disease worldwide. DNA methylation is associated with the occurrence and development of asthma. We are aimed at assuring differential expressed genes (DEGs) modified by aberrantly methylated genes (DMGs) and pathways related to asthma by integrating bioinformatics analysis. METHODS: One mRNA dataset (GSE64913) and one gene methylation dataset (GSE137716) were selected from the Gene Expression Omnibus (GEO) database. Functional enrichment analysis was performed using GeneCodies 4.0 database. All gene expression matrices were analyzed by Gene set enrichment analysis (GSEA) software. STRING was applied to construct a protein-protein interaction (PPI) network to find the hub genes. Then, electronic validation was performed to verify the hub genes, followed by the evaluation of diagnostic value. Eventually, quantitative real-time polymerase chain reaction (qRT-PCR) was utilized to detect the expression of hub genes. RESULTS: In total, 14 hypomethylated/high-expression genes and 10 hypermethylated/low-expression genes were obtained in asthma. Among them, 10 hub genes were identified in the PPI network. Functional analysis demonstrated that the differentially methylated/expressed genes were primarily associated with the lung development, cytosol and protein binding. Notably, HLA-DOA was enriched in asthma. FKBP5, WNT5A, TM4SF1, PDK4, EPAS1 and GMPR had potential diagnostic value for asthma. CONCLUSION: The project explored the pathogenesis of asthma, which may provide a research basis for the prediction and the drug development of asthma.

12.
Angew Chem Int Ed Engl ; 61(42): e202210576, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36037027

RESUMO

Photocatalytic conversion of CO2 into syngas is a promising way to address the energy and environmental challenges. Here we report the integration of Ni-Co dual sites on Ni doped Co3 O4 ultrathin nanosheets assembled double-hollow nanotube (Ni-Co3 O4 NSDHN) for efficient photoreduction of low-concentration CO2 . Quasi in situ spectra and density functional theory calculations demonstrate that the declining of d-band center of Ni-Co dual sites enables the electrons accumulation in the dxz /dyz -2π* and dz2 -5σ orbitals. As a result, the binding strength of *CO is weakened and the *H adsorption site is modulated from metal sites to an oxygen site. Remarkably, Ni-Co3 O4 NSDHN exhibits superior diluted CO2 photoconversion activity and controllable selectivity under the irradiation of visible light or even natural sunlight. A syngas evolution rate of 170.0 mmol g-1 h-1 with an apparent quantum yield of 3.7 % and continuously adjustable CO/H2 ratios from 1 : 10 to 10 : 1 are achieved.

13.
ACS Macro Lett ; 11(8): 1041-1048, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35920565

RESUMO

Dry polymer brushes have attracted great attention because of their potential utility in regulating interface properties. However, it is still unknown whether dry polymer brushes will exhibit degrafting behavior as a result of thermal annealing. Herein, a study of the conformational entropy effect on thermal degrafting of dry polystyrene (PS) brushes is presented. For PS brushes with an initial grafting density (σpini) of 0.61 nm-2, degrafting behavior was observed at 393 K, and the equilibrium σp was approximately 0.14 nm-2 at 413 K. However, for brushes with σpini ≤ 0.14 nm-2, thermal degrafting was not observed even if the temperature was increased to 453 K. Furthermore, we found that the degrafting rate was faster for PS brushes with higher σpini and higher molecular weights when σpini > 0.14 nm-2. Our findings confirmed that degrafting is a mechanochemical activation process driven by tension imposed on bonds that anchor the chains to the surface, and the process is amplified by conformational entropy.


Assuntos
Polímeros , Poliestirenos , Entropia , Conformação Molecular , Polímeros/química , Poliestirenos/química , Propriedades de Superfície
14.
Sensors (Basel) ; 22(12)2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35746251

RESUMO

In this study, an unmanned aerial vehicle (UAV) with a camera and laser ranging module was developed to inspect bridge cracks. Four laser ranging units were installed adjacent to the camera to measure the distance from the camera to the object to calculate the object's projection plane and overcome the limitation of vertical photography. The image processing method was adopted to extract crack information and calculate crack sizes. The developed UAV was used in outdoor bridge crack inspection tests; for images taken at a distance of 2.5 m, we measured the crack length, and the error between the result and the real length was less than 0.8%. The developed UAV has a dual-lens design, where one lens is used for bridge inspections and the other lens is used for flight control. The camera of the developed UAV can be rotated from the horizontal level to the zenith according to user requirements; thus, this UAV achieves high safety and efficiency in bridge inspections.

15.
Nat Commun ; 13(1): 2591, 2022 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-35546157

RESUMO

Single cluster catalysts (SCCs) are considered as versatile boosters in heterogeneous catalysis due to their modifiable single cluster sites and supports. In this work, we report subnanometric Cu clusters dispersed on Fe-doped MoO2 support for biomass-derived furfural upgrading. Systematical characterizations suggest uniform Cu clusters (composing four Cu atoms in average) are homogeneously immobilized on the atomically Fe-doped ultrafine MoO2 nanocrystals (Cu4/Fe0.3Mo0.7O2@C). The atomic doping of Fe into MoO2 leads to significantly modified electronic structure and consequently charge redistribution inside the supported Cu clusters. The as-prepared Cu4/Fe0.3Mo0.7O2@C shows superior catalytic performance in the oxidative coupling of furfural with C3~C10 primary/secondary alcohols to produce C8~C15 aldehydes/ketones (aviation biofuel intermediates), outperforming the conventionally prepared counterparts. DFT calculations and control experiments are further carried out to interpret the structural and compositional merits of Cu4/Fe0.3Mo0.7O2@C in the oxidative coupling reaction, and elucidate the reaction pathway and related intermediates.


Assuntos
Aviação , Furaldeído , Álcoois/química , Biocombustíveis , Catálise , Furaldeído/química
16.
Exp Gerontol ; 163: 111796, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35381315

RESUMO

Increased visceral fat is strongly associated with a series of metabolic complications. Postmenopausal women have an increased risk of visceral fat accumulation, metabolic disorders, and a high incidence of cardiovascular events. However, the effect of estrogen replacement therapy on visceral adipose tissue among postmenopausal women of different ages remains controversial, and the underlying mechanism remains unclear. Hence, it is important to understand when estrogen replacement therapy affects the function of visceral adipose tissue (VAT). Therefore, we collected VAT from pre- and post-menopausal females and we observed increased pro-inflammatory cytokines and insulin resistance-inducing factors, decreased insulin-sensitizing factors, and thermogenic factors in VAT of postmenopausal women. The analysis of adipocytes isolated from the VAT of females of different ages indicated that adiponectin and browning signature genes were significantly decreased with estrogen treatment in postmenopausal women, but were not altered in the young group. Estrogen supplementation in aged female mice (22 m) significantly prevented visceral fat accumulation. However, it deteriorated VAT function by inducing pro-inflammatory cytokines and insulin resistance-inducing factors and decreasing insulin-sensitizing and thermogenic factors. Mechanistically, estrogen induced the expression of long non-coding RNA Gas5 via binding ERα in premenopausal women, which therefore suppressed IGF2BP1 to maintain VAT function. After menopause, with the reversal of ERα/ERß ratio in VAT, estrogen supplementation mainly worked through ERß, which led to low expression levels of Gas5 and eventually caused VAT dysfunction. Our study demonstrated the adverse effects of estrogen supplementation on VAT function in aged postmenopausal population and further elucidated the involved mechanism.


Assuntos
Receptor alfa de Estrogênio , Resistência à Insulina , Idoso , Animais , Citocinas/metabolismo , Suplementos Nutricionais , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Estrogênios/metabolismo , Estrogênios/farmacologia , Feminino , Humanos , Insulina/metabolismo , Gordura Intra-Abdominal/metabolismo , Camundongos , Obesidade Abdominal , Pós-Menopausa
17.
Front Med (Lausanne) ; 9: 827174, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35479954

RESUMO

Frailty is a critical aging-related syndrome but the underlying metabolic mechanism remains poorly understood. The aim of this study was to identify novel biomarkers and reveal potential mechanisms of frailty based on the integrated analysis of metabolome and gut microbiome. In this study, twenty subjects consisted of five middle-aged adults and fifteen older adults, of which fifteen older subjects were divided into three groups: non-frail, pre-frail, and frail, with five subjects in each group. The presence of frailty, pre-frailty, or non-frailty was established according to the physical frailty phenotype (PFP). We applied non-targeted metabolomics to serum and feces samples and used 16S rDNA gene sequencing to detect the fecal microbiome. The associations between metabolites and gut microbiota were analyzed by the Spearman's correlation analysis. Serum metabolic shifts in frailty mainly included fatty acids and derivatives, carbohydrates, and monosaccharides. Most of the metabolites belonging to these classes increased in the serum of frail older adults. Propylparaben was found to gradually decrease in non-frail, pre-frail, and frail older adults. Distinct changes in fecal metabolite profiles and gut microbiota were also found among middle-aged adults, non-frail and frail older subjects. The relative abundance of Faecalibacteriu, Roseburia, and Fusicatenibacter decreased while the abundance of Parabacteroides and Bacteroides increased in frailty. The above altered microbes were associated with the changed serum metabolites in frailty, which included dodecanedioic acid, D-ribose, D-(-)-mannitol, creatine and indole, and their related fecal metabolites. The changed microbiome and related metabolites may be used as the biomarkers of frailty and is worthy of further mechanistic studies.

18.
ACS Nano ; 16(3): 4517-4527, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35245030

RESUMO

Solar-driven conversion of CO2 is considered an efficient way to tackle the energy and environmental crisis. However, the photocatalytic performance is severely restricted due to the insufficient accessible active sites and inhibited electron transfer efficiency. This work demonstrates a general in situ topological transformation strategy for the integration of uniform Co-based species to fabricate a series of multishelled superstructures (MSSs) for CO2 photocatalytic conversion. Thorough characterizations reveal the obtained MSSs feature ultrathin Co-based nanosheet assembled polyhedral structures with tunable shell numbers, inner cavity sizes, and compositions. The superstructures increase the spatial density of Co-based active sites while maintaining their high accessibility. Further, the ultrathin nanosheets also facilitate the transfer of photogenerated electrons. As a result, the ZnCo bimetallic hydroxide featuring an ultrathin nanosheet assembled quadruple-shell hollow structure (ZnCo-OH QUNH) exhibits high photocatalytic efficiency toward CO2 reduction with a CO evolution rate of 134.2 µmol h-1 and an apparent quantum yield of 6.76% at 450 nm. The quasi in situ spectra and theoretical calculations disclose that Co sites in ZnCo-OH QUNH act as highly active centers to stabilize the COOH* intermediate, while Zn species play the role of adsorption sites for the [Ru(bpy)3]2+ molecules.

19.
J Hazard Mater ; 425: 127599, 2022 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-34895929

RESUMO

The development of efficacious photocatalysts for the elimination of contaminants in water remains a challenge. Herein, a promising Ag nanoparticles-decorated copper-phenylacetylide (Ag/PhC2Cu) plasmonic photocatalyst was fabricated for the reduction of hexavalent chromium (Cr(VI)) and degradation of pharmaceutical and personal care products (PPCPs). Typically, the optimized 5Ag/PhC2Cu could rapidly reduce Cr(VI) (98.1% within 12 min), and degrade norfloxacin (NOR) (100% within 40 min) with a 56.2% mineralization rate under visible light. The superior photocatalytic activity of Ag/PhC2Cu was attributed to the synergistic effects of the highly reducing photoinduced electrons conferred by the PhC2Cu (-1.98 eV), and Ag nanoparticles in promoting photocarrier separation and enhancing solar-energy-conversion efficiencies. Subsequently, the photocatalytic reaction mechanism of Ag/PhC2Cu was investigated. It was found that e- and O2•- were the main reactive species for Cr(VI) reduction, while O2•- and h+ were primarily responsible for the degradation of NOR. Of note, the Ag/PhC2Cu system could effectively generate H2O2 and partially decomposed it to •OH, which might be involved in NOR mineralization. This study not only demonstrates a highly active photocatalytic system for the remediation of environmental pollution and sustainable solar-to-chemical energy conversion, but contributes to the future exploration of multifunctional plasmonic photocatalysts.


Assuntos
Cobre , Nanopartículas Metálicas , Catálise , Cromo , Peróxido de Hidrogênio , Cinética , Luz , Polímeros , Prata
20.
ACS Appl Mater Interfaces ; 13(38): 45609-45618, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34542276

RESUMO

Visible-light-driven photocatalytic CO2 reduction is considered an appealing strategy to mitigate the energy crisis and environmental issues, whereas the reactivity is limited due to the difficulties in activation of inert CO2 molecule and efficient transportation of photoinduced carriers. Herein, we report the design of novel Fe doped CoP hierarchical double-shelled nanocages (Fe-CoP HDSNC) via a MOF-templated approach for highly efficient visible-light-driven CO2 reduction. The unique hierarchical double-shelled hollow architectures can greatly shorten the charge transfer distances and also expose abundant reactive sites. Moreover, Fe atoms doping is able to reduce the CO2 activation energy barrier through stabilizing the *COOH intermediates and promote the CO desorption by destabilizing the CO* adduct. As expected, the Fe-CoP HDSNC achieves an unprecedented catalytic efficiency in visible-light-driven CO2 reduction with an up to 3.25% apparent quantum yield and 90.3% CO selectivity, superior to most of the state-of-the-art photocatalysts under comparable conditions. More importantly, the Fe-CoP HDSNC is also highly effective under diluted CO2 atmosphere, suggesting the practicability of the present photocatalytic system.

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