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1.
Sci Rep ; 13(1): 18332, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884583

RESUMO

Acute exacerbation chronic obstructive pulmonary disease (AECOPD) has a high mortality rate. However, there is no efficiency biomarker for diagnosing AECOPD. The purpose of this study was to find biomarkers that can quickly and accurately diagnose AECOPD.45 normal controls (NC), 42 patients with stable COPD (SCOPD), and 66 patients with AECOPD were enrolled in our study. Serum exosomes were isolated by ultracentrifuge and verified by morphology and specific biomarkers. Fluorescent quantitation polymerase chain reaction (qRT-PCR) was used to detect the expression of micro RNAs (miRNAs), including miR-660-5p, miR-1258, miR-182-3p, miR-148a-3p, miR-27a-5p and miR-497-5p in serum exosomes and serum. Logistic regression and machine learning methods were used to constructed the diagnostic models of AECOPD. The levels of miR-1258 in the patients with AECOPD were higher than other groups (p < 0.001). The ability of exosomal miR-1258 (AUC = 0.851) to identify AECOPD from SCOPD was superior to other biomarkers, and the combination of exosomal miR-1258 and NLR can increase the AUC to 0.944, with a sensitivity of 81.82%, and specificity of 97.62%. The cross-validation of the models displayed that the logistic regression model based on exosomal miR-1258, NLR and neutrophil count had the best accuracy (0.880) in diagnosing AECOPD from SCOPD. The three most correlated biomarkers with serum exosome miR-1258 were neutrophil count (r = 0.57, p < 0.001), WBC (r = 0.50, p < 0.001) and serum miR-1258 (r = 0.33, p < 0.001). In conclusion, serum exosomal miR-1258 is associated with inflammation, and can be used as a valuable and reliable biomarker for the diagnosis of AECOPD, and the establishment of diagnostic model based on miR-1258, NLR and neutrophils count can help to improving the accuracy of AECOPD diagnosis.


Assuntos
Exossomos , MicroRNAs , Doença Pulmonar Obstrutiva Crônica , Humanos , Biomarcadores , MicroRNAs/metabolismo , Inflamação/metabolismo , Exossomos/genética , Exossomos/metabolismo , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/genética
2.
Adv Mater ; 35(21): e2300064, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36872578

RESUMO

Solar-driven CO2 reduction by water with a Z-scheme heterojunction affords an avenue to access energy storage and to alleviate greenhouse gas (GHG) emissions, yet the separation of charge carriers and the integrative regulation of water oxidation and CO2 activation sites remain challenging. Here, a BiVO4 /g-C3 N4 (BVO/CN) Z-scheme heterojunction as such a prototype is constructed by spatially separated dual sites with CoOx clusters and imidazolium ionic liquids (IL) toward CO2 photoreduction. The optimized CoOx -BVO/CN-IL delivers an ≈80-fold CO production rate without H2 evolution compared with urea-C3 N4 counterpart, together with nearly stoichiometric O2 gas produced. Experimental results and DFT calculations unveil the cascade Z-scheme charge transfer and subsequently the prominent redox co-catalysis by CoOx and IL for holes-H2 O oxidation and electrons-CO2 reduction, respectively. Moreover, in situ µs-transient absorption spectra clearly show the function of each cocatalyst and quantitatively reveal that the resulting CoOx -BVO/CN-IL reaches up to the electron transfer efficiency of 36.4% for CO2 reduction, far beyond those for BVO/CN (4.0%) and urea-CN (0.8%), underlining an exceptional synergy of dual reaction sites engineering. This work provides deep insights and guidelines for the rational design of highly efficient Z-scheme heterojunctions with precise redox catalytic sites toward solar fuel production.

3.
Nat Commun ; 14(1): 1457, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36928357

RESUMO

Photocatalytic CO2 conversion promises an ideal route to store solar energy into chemical bonds. However, sluggish electron kinetics and unfavorable product selectivity remain unresolved challenges. Here, an ionic liquid, 1-ethyl-3-methylimidazolium tetrafluoroborate, and borate-anchored Co single atoms were separately loaded on ultrathin g-C3N4 nanosheets. The optimized nanocomposite photocatalyst produces CO and CH4 from CO2 and water under UV-vis light irradiation, exhibiting a 42-fold photoactivity enhancement compared with g-C3N4 and nearly 100% selectivity towards CO2 reduction. Experimental and theoretical results reveal that the ionic liquid extracts electrons and facilitates CO2 reduction, whereas Co single atoms trap holes and catalyze water oxidation. More importantly, the maximum electron transfer efficiency for CO2 photoreduction, as measured with in-situ µs-transient absorption spectroscopy, is found to be 35.3%, owing to the combined effect of the ionic liquid and Co single atoms. This work offers a feasible strategy for efficiently converting CO2 to valuable chemicals.

4.
Adv Mater ; 35(15): e2211575, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36680460

RESUMO

Ultrasensitively selective detection of trace polycyclic aromatic hydrocarbons (PAHs) like phenanthrene (PHE) is critical but remains challenging. Herein, atomically dispersed Zn sites on g-C3 N4 nanosheets (sZn-CN) are constructed by thermal polymerization of a Zn-cyanuric acid-melamine supramolecular precursor for the fluorescence detection of PHE. A high amount (1.6 wt%) of sZn is grafted in the cave of CN with one N vacancy in the form of unique Zn(II)N5 coordination. The optimized sZn-CN achieves a wide detection range (1 ng L-1 to 5 mg L-1 ), ultralow detection limit (0.35 ng L-1 , with 5-order magnitude improvement over CN), and ultrahigh selectivity toward PHE even among typical PAHs based on the built PHE-CN dual ratiometric fluorescence method. By means of in situ Fourier transform infrared spectroscopy, time-resolved absorption and fluorescence spectroscopy, and theoretical calculations, the resulting superior detection performance is attributed to the favorable selective adsorption of PHE on as-constructed atomic Zn(II)N5 sites via the ionic cation-π interactions (Znδ+ C2 δ- type), and the fluorescence quenching is dominated by the inner filter effect (IFE) from the multilayer adsorption of PHE at low concentrations, while it is done by the protruded photogenerated electron-transfer process, as well as IFE from the monolayer adsorption of PHE at ultralow concentration.

5.
Adv Mater ; 34(41): e2205303, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35986557

RESUMO

To rationally design single-atom metal-organic framework (MOF)-involving photocatalysts remains an ongoing challenge for efficient CO2 conversion. Here, cuppy microstructures, consisting of a Ti(IV)-oxo node and three linked carboxylic moieties, in the single-coordination-layer Ti2 (H2 dobdc)3 MOF (NTU-9) are exploited to immobilize abundant single Ni(II) sites (Ni@MOF). The coupling of Ni@MOF with BiVO4 (BVO) nanosheets by H-bonding-induced assembly process obtains wide-spectrum 2D heterojunctions. The optimal heterojunction exhibits competitive performance and enables around 66-fold CO2 conversion of that for BVO nanoparticles by pure water, with nearly 100% CO selectivity. The exceptional photoactivity is attributed to favorable S-scheme charge transfer from BVO to MOF then to single Ni(II) sites. Noteworthily, single Ni(II) sites anchored by the Ti(IV)-oxo node and vicinal carboxylic moieties serving as a unique local microenvironment (LME) are found to synergistically catalyze CO2 conversion. Specifically, the hydroxyl groups of carboxylic moieties can form H-bonds with CO2 to promote its adsorption on single Ni(II) sites, and also can provide accessible protons to facilitate H-assisted CO2 reduction. Moreover, the CO desorption and subsequent CO2 adsorption on single Ni(II) sites with LME is proved to be thermodynamically favored, and hence dominates the high CO selectivity. This work highlights the significance of modulating the LME of single atoms to rationally design photocatalysts for realizing carbon neutralization.

6.
Sci Rep ; 12(1): 9810, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35697754

RESUMO

Rheumatoid arthritis (RA) is chronic systemic disease that can cause joint damage, disability and destructive polyarthritis. Current diagnosis of RA is based on a combination of clinical and laboratory features. However, RA diagnosis can be difficult at its disease onset on account of overlapping symptoms with other arthritis, so early recognition and diagnosis of RA permit the better management of patients. In order to improve the medical diagnosis of RA and evaluate the effects of different clinical features on RA diagnosis, we applied an artificial neural network (ANN) as the training algorithm, and used fivefold cross-validation to evaluate its performance. From each sample, we obtained data on 6 features: age, sex, rheumatoid factor, anti-citrullinated peptide antibody (CCP), 14-3-3η, and anti-carbamylated protein (CarP) antibodies. After training, this ANN model assigned each sample a probability for being either an RA patient or a non-RA patient. On the validation dataset, the F1 for all samples by this ANN model was 0.916, which was higher than the 0.906 we previously reported using an optimal threshold algorithm. Therefore, this ANN algorithm not only improved the accuracy of RA diagnosis, but also revealed that anti-CCP had the greatest effect while age and anti-CarP had a weaker on RA diagnosis.


Assuntos
Artrite Reumatoide , Autoanticorpos , Artrite Reumatoide/diagnóstico , Humanos , Redes Neurais de Computação , Peptídeos Cíclicos , Fator Reumatoide
7.
Cell Stem Cell ; 29(4): 545-558.e13, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35395187

RESUMO

Zebrafish and mammalian neonates possess robust cardiac regeneration via the induction of endogenous cardiomyocyte (CM) proliferation, but adult mammalian hearts have very limited regenerative potential. Developing small molecules for inducing adult mammalian heart regeneration has had limited success. We report a chemical cocktail of five small molecules (5SM) that promote adult CM proliferation and heart regeneration. A high-content chemical screen, along with an algorithm-aided prediction of small-molecule interactions, identified 5SM that efficiently induced CM cell cycle re-entry and cytokinesis. Intraperitoneal delivery of 5SM reversed the loss of heart function, induced CM proliferation, and decreased cardiac fibrosis after rat myocardial infarction. Mechanistically, 5SM potentially targets α1 adrenergic receptor, JAK1, DYRKs, PTEN, and MCT1 and is connected to lactate-LacRS2 signaling, leading to CM metabolic switching toward glycolysis/biosynthesis and CM de-differentiation before entering the cell-cycle. Our work sheds lights on the understanding CM regenerative mechanisms and opens therapeutic avenues for repairing the heart.


Assuntos
Infarto do Miocárdio , Miócitos Cardíacos , Animais , Proliferação de Células , Coração , Mamíferos , Infarto do Miocárdio/tratamento farmacológico , Miócitos Cardíacos/metabolismo , Ratos , Transdução de Sinais , Peixe-Zebra
8.
Adv Mater ; 33(48): e2105482, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34569106

RESUMO

The configuration regulation of single-atom photocatalysts (SAPCs) can significantly influence the interfacial charge transfer and subsequent catalytic process. The construction of conventional SAPCs for aqueous CO2 reduction is mainly devoted toward favorable activation and photoreduction of CO2 , however, the role of water is frequently neglected. In this work, single Ni atoms are successfully anchored by boron-oxo species on g-C3 N4 nanosheets through a facile ion-exchange method. The dative interaction between the B atom and the sp2 N atom of g-C3 N4 guarantees the high dispersion of boron-oxo species, where O atoms coordinate with single Ni (II) sites to obtain a unique six-oxygen-coordinated configuration. The optimized single-atom Ni photocatalyst, rivaling Pt-modified g-C3 N4 nanosheets, provides excellent CO2 reduction rate with CO and CH4 as products. Quasi-in-situ X-ray photoelectron spectra, transient absorption spectra, isotopic labeling, and in situ Fourier transform infrared spectra reveal that as-fabricated six-oxygen-coordinated single Ni (II) sites can effectively capture the photoelectrons of CN along the BO bridges and preferentially activate adsorbed water to produce H atoms to eventually induce a hydrogen-assisted CO2 reduction. This work diversifies the synthetic strategies for single-atom catalysts and provides insight on correlation between the single-atom configuration and reaction pathway.

9.
Cell Discov ; 6: 74, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33133634

RESUMO

It remains challenging to construct a complete cell lineage map of the origin of vascular endothelial cells in any vertebrate embryo. Here, we report the application of in toto light-sheet fluorescence imaging of embryos to trace the origin of vascular endothelial cells (ECs) at single-cell resolution in zebrafish. We first adapted a previously reported method to embryo mounting and light-sheet imaging, created an alignment, fusion, and extraction all-in-one software (AFEIO) for processing big data, and performed quantitative analysis of cell lineage relationships using commercially available Imaris software. Our data revealed that vascular ECs originated from broad regions of the gastrula along the dorsal-ventral and anterior-posterior axes, of which the dorsal-anterior cells contributed to cerebral ECs, the dorsal-lateral cells to anterior trunk ECs, and the ventral-lateral cells to posterior trunk and tail ECs. Therefore, this work, to our knowledge, charts the first comprehensive map of the gastrula origin of vascular ECs in zebrafish, and has potential applications for studying the origin of any embryonic organs in zebrafish and other model organisms.

11.
Adv Sci (Weinh) ; 7(16): 2001543, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32832373

RESUMO

Realization of solar-driven aerobic organic transformation under atmospheric pressure raises the great challenge for efficiently activating O2 by tailored photocatalysts. Guided by theoretical calculation, phosphate groups are used to induce the construction of ultrathin Co phthalocyanine/g-C3N4 heterojunctions (CoPc/P-CN, ≈4 nm) via strengthened H-bonding interfacial connection, achieving an unprecedented 14-time photoactivity improvement for UV-vis aerobic 2,4-dichlorophenol degradation compared to bulk CN by promoted activation of O2. It is validated that more •O2 - radicals are produced through the improved photoreduction of O2 by accelerated photoelectron transfer from CN to the ligand of CoPc and then to the abundant single Co-N4 (II) catalytic sites, as endowed by the matched dimension, intimate interface even at the molecular level, and high CoPc dispersion of resulted heterojunctions. Interestingly, CoPc/P-CN also exhibits outstanding photoactivities in the aerobic oxidation of aromatic alcohols. This work showcases a feasible route to realize efficient photocatalytic O2 activation by exploiting the potential of ultrathin metal phthalocyanine (MPc) assemblies with abundant single-atom sites. More importantly, a universal facile strategy of H-bonding-dominating construction of MPc-involved heterojunctions is successfully established.

12.
Nanoscale ; 12(18): 10010-10018, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32350498

RESUMO

It is highly desirable to improve charge separation and to provide catalytic functions for the efficient photocatalytic CO2 reduction reaction (CO2RR) on g-C3N4 (CN). Here, dimension-matched ultrathin NiMOF/CN heterojunctions have been successfully constructed by the in situ growth of NiMOF nanosheets on hydroxylated and 1,4-aminobenzoic acid (AA) functionalized CN nanosheets, respectively, with ultrasonic assistance. The resultant NiMOF/CN heterojunctions exhibited excellent photocatalytic activities for the CO2RR to produce CO and CH4, especially NiMOF/CN-AA, which had photoactivity 18 times higher than that of bare CN. Based on the surface photovoltage responses, wavelength-dependent photocurrent action spectra, electrochemical impedance spectra, and CO2 electrochemical reduction data, it is clearly confirmed that the exceptional photoactivity mainly resulted from the favorable charge transport properties of ultrathin CN and coupled NiMOF, and from the greatly enhanced charge separation via excited high-level electron transfer from CN to NiMOF in the resultant intimately contacted heterojunction caused by the induction effect of AA, and also from the provided catalytic functionality of the central Ni(ii) for CO2 activation. This work provides a feasible synthetic protocol to fabricate MOF-containing dimension-matched heterojunctions with good charge separation for efficient photocatalysis.

13.
Angew Chem Int Ed Engl ; 58(32): 10873-10878, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31199043

RESUMO

Cascade charge transfer was realized by a H-bond linked zinc phthalocyanine/BiVO4 nanosheet (ZnPc/BVNS) composite, which subsequently works as an efficient wide-visible-light-driven photocatalyst for converting CO2 into CO and CH4 , as shown by product analysis and 13 C isotopic measurement. The optimized ZnPc/BVNS nanocomposite exhibits a ca. 16-fold enhancement in the quantum efficiency compared with the reported BiVO4 nanoparticles at the excitation of 520 nm with an assistance of 660 nm photons. Experimental and theoretical results show the exceptional activities are attributed to the rapid charge separation by a cascade Z-scheme charge transfer mechanism formed by the dimension-matched ultrathin (ca. 8 nm) heterojunction nanostructure. The central Zn2+ in ZnPc could accept the excited electrons from the ligand and then provide a catalytic function for CO2 reduction. This Z-scheme is also feasible for other MPc, such as FePc and CoPc, together with BVNS.

14.
Sci Rep ; 7(1): 1303, 2017 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-28465558

RESUMO

It is highly desired to improve the photoelectrochemical (PEC) performance of nanosized WO3 by artificially modulating the photogenerated electrons and holes simultaneously. Herein, WO3 nanoplates have been successfully prepared by a simple one-pot two-phase separated hydrolysis-solvothermal method, and then co-modified with RGO and phosphate acid successively by wet chemical processes. Subsequently, the as-prepared WO3-based nanoplates were immobilized on the conductive glasses to explore the PEC activities for both water oxidation to evolve O2 and phenol degradation. It is clearly demonstrated that the co-modified WO3 nanoplates exhibit significantly improved PEC activities compared with pristine WO3, especially for that with the amount-optimized modifiers by ca. 6-time enhancement. Mainly based on the evaluated hydroxyl radical amounts produced and the electrochemical impedance spectra, it is suggested that the improved PEC activities are attributed to the greatly enhanced photogenerated charge separation after chemically modification with RGO and phosphate groups to WO3, respectively by transferring electrons as the collectors and trapping holes via the formed negative field after phosphate disassociation. This work provides a feasible synthetic strategy to improve the photoactivities of nanosized WO3 for energy production and environmental remediation.

15.
Chem Commun (Camb) ; 51(20): 4259-62, 2015 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-25669483

RESUMO

A novel microspherical composite with an Au@SiO2 core and mesoporous aluminosilica shell is synthesized and used as the heterogeneous catalyst in the aerobic epoxidation of cis-cyclooctene, exhibiting great catalytic activity and stability.


Assuntos
Ciclo-Octanos/química , Ouro/química , Dióxido de Silício/química , Silicatos de Alumínio/química , Catálise , Porosidade
16.
Inorg Chem ; 53(16): 8529-37, 2014 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-25100615

RESUMO

In this report, three new metal-organic frameworks (MOFs), [Co3(µ3-OH)(HBTC)(BTC)2Co(HBTC)]·(HTEA)3·H2O (NTU-Z30), [Co(BTC)]·HTEA·H2O (NTU-Z31), [Co3(BTC)4]·(HTEA)4 (NTU-Z32), where H3BTC = 1,3,5-benzenetricarboxylic acid, TEA = triethylamine, and NTU = Nanyang Technological University, have been successfully synthesized under surfactant media and have been carefully characterized by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetric analysis, and IR spectromtry. NTU-Z30 has an unusual trimeric [Co3(µ3-OH)(COO)7] secondary building unit (SBU), which is different from the well-known trimeric [Co3O(COO)6] SBU. The topology studies indicate that NTU-Z30 and NTU-Z32 possess two new topologies, 3,3,6,7-c net and 2,8-c net, respectively, while NTU-Z31 has a known topology rtl type (3,6-c net). Magnetic analyses show that all three materials have weak antiferromagnetic behavior. Furthermore, NTU-Z30 has been selected as the heterogeneous catalyst for the aerobic epoxidation of alkene, and our results show that this material exhibits excellent catalytic activity as well as good stability. Our success in growing new crystalline cobalt 1,3,5-benzenetricarboxylate MOFs under surfactant media could pave a new road to preparing new diverse crystalline inorganic materials through a surfactant-thermal method.


Assuntos
Cobalto/química , Compostos Organometálicos/química , Tensoativos/química , Ácidos Tricarboxílicos/química , Cristalografia por Raios X , Modelos Moleculares , Compostos Organometálicos/síntese química
17.
ChemSusChem ; 7(9): 2670-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25110998

RESUMO

Currently, levulinic acid (LA) and formic acid (FA) are considered as important carbohydrates for the production of value-added chemicals. Their direct production from biomass will open up a new opportunity for the transformation of biomass resource to valuable chemicals. In this study, one-pot transformation of cellobiose into LA and FA was demonstrated, using a series of multiple-functional ionic liquid-based polyoxometalate (IL-POM) hybrids as catalytic materials. These IL-POMs not only markedly promoted the production of valuable chemicals including LA, FA and monosaccharides with high selectivities, but also provided great convenience of the recovery and the reuse of the catalytic materials in an environmentally friendly manner. Cellobiose conversion of 100%, LA selectivity of 46.3%, and FA selectivity of 26.1% were obtained at 423 K and 3 MPa for 3 h in presence of oxygen. A detailed catalytic mechanism for the one-pot transformation of cellobiose was also presented.


Assuntos
Celobiose/química , Formiatos/química , Líquidos Iônicos/química , Ácidos Levulínicos/química , Compostos de Tungstênio/química , Catálise , Concentração de Íons de Hidrogênio , Oxirredução
18.
Dalton Trans ; 43(6): 2559-65, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24316796

RESUMO

A new hexaprismane Co(II)6(µ3-OH)6 cluster-based three-dimensional coordination polymer ({Co(µ3-OH)(HCOO)0.72(CH3COO)0.28}n, Co6-CP) was successfully synthesized and characterized with single-crystal XRD, IR spectra, TGA spectra and elemental analysis. Co6-CP was used as an effective heterogeneous catalyst for the aerobic epoxidation of various alkenes. For the catalytic epoxidation of trans-stilbene, the conversion and selectivity towards the epoxide reached 98.6 and 98.0%, respectively. Also, an average TOF of 22 h(-1) was obtained for the reaction. The results indicated that Co6-CP displayed excellent aerobic epoxidation activity among the reported coordination polymer materials, even rivaling the traditional heterogeneous cobalt catalysts. The influence of the reaction parameters such as temperature and oxygen flow rate for the epoxidation of the trans-stilbene were also studied in detail.

19.
Chem Commun (Camb) ; 47(22): 6452-4, 2011 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-21547303

RESUMO

The aerobic oxidation of 1-phenylethanol over a carbon nanotube supported palladium catalyst was improved with an ionic liquid additive [emim][NTf(2)], showing an excellent TON of 149,000 which can be maintained for 5 recycle runs.


Assuntos
Líquidos Iônicos/química , Paládio/química , Álcool Feniletílico/química , Catálise , Nanotubos de Carbono/química , Oxirredução , Oxigênio/química , Espectroscopia Fotoeletrônica
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