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In this work, hollow CoS2 particles were prepared by a one-step sulfurization strategy using polyoxometalate-based metal-organic frameworks as the precursor. The morphology and structure of CoS2 have been monitored by scanning electron microscopy, X-ray photoelectron spectroscopy, and X-ray powder diffraction. The mechanism for the formation of CoS2 is discussed. The reaction time and sulfur content are found to be important factors that affect the morphology and pure phase formation of CoS2, and a hollow semioctahedral morphology of CoS2 with open voids was obtained when the sulfur source was twice as large as the precursor and the reaction time was 24 h. The CoS2 (24 h) particles show an excellent peroxidase-like activity for the oxidation of colorless 3,3',5,5'-tetramethylbenzidine (TMB) to blue oxidized (oxTMB) by hydrogen peroxide. The polyoxometalate used as a precursor helps to stabilize oxTMB during catalytic oxidation, forming a stable curve platform for at least 8 min. Additionally, the colorimetric detection of hydroquinone is developed with a low detection limit of 0.42 µM. This research provides a new strategy to design hollow materials with high peroxidase-mimicking activity.
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A stable and innovative composite film-modified electrode based on Dawson polyoxometalates H8P2Mo16V2O62 (P2Mo16V2) and ionic liquid (BMIMBr)-decorated carbon nanotubes, annotated as PEI/(P2Mo16V2/BMIMBr-CNTs)8, has been constructed by using the layer-by-layer self-assembly (LBL) method for the determination of L-tyrosine. The combination of three active components not only offers higher conductivity to facilitate rapid electron transfer, but also avoids the accumulation of P2Mo16V2 to expand the contact area and increase the reactive active sites. The modified electrode exhibits outstanding sensing performance for determination of Tyr with wide linear determination range of 5.8×10-7 M ~ 1.2×10-4 M, low determination limit of 1.7×10-7M (S/N=3), high selectivity for common interferences, and excellent stability at the potential of +0.78 V (vs. Ag/AgCl (3 M KCl)). The relative standard deviation (RSD) of 4.3% for five groups of parallel experiments shows the satisfactory repeatability of PEI/(P2Mo16V2/BMIMBr-CNTs)8. In addition, for determination of Tyr, the PEI/(P2Mo16V2/BMIMBr-CNTs)8 shows good recoveries of 98.8-99.8% in meat floss, which can be feasible in practical application.
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Líquidos Iônicos , Nanotubos de Carbono , Tirosina , EletrodosRESUMO
Phenols are widely used for commercial production, while they pose a hazard to the environment and human health. Thus, investigation of convenient and efficient methods for the detection, discrimination, and degradation of phenols becomes particularly important. Herein, two new polyoxometalate (POM)-based compounds, [Co2(btap)4(H2O)4][SiW12O40] (Co-POM) and [Ni2(btap)4(H2O)4][SiW12O40] (Ni-POM) (btap = 3,5-bis(triazol-1-yl)pyridine), are prepared via a hydrothermal synthesis method. The compounds show a fascinating structural feature of a POM-encapsulated twofold interpenetrating dia metal-organic framework. More importantly, besides the novel structures, the compound Co-POM realizes three functions, namely, the simultaneous detection, discrimination, and degradation of phenols. Specifically, Co-POM shows an excellent colorimetric detection performance toward phenol with a detection limit (LOD) ca. 1.32 µM, which is lower than most reported colorimetric detectors for phenol. Also, a new colorimetric sensor system based on Co-POM can discriminate phenol, 4-chlorophenol, and o-cresol with ease. Further, Co-POM exhibits a photocatalytic degradation property for 4-chlorophenol under irradiation of visible light with the highest degradation rate at 62% after irradiation for 5 h. Therefore, this work provides the first example of a POMs-based multifunctional material for achieving the detection, discrimination, and degradation of phenolic pollutants.
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Poluentes Ambientais , Estruturas Metalorgânicas , Compostos de Tungstênio , Ânions , Dióxido de Carbono , Clorofenóis , Humanos , Fenol , Fenóis , Polieletrólitos , Piridinas , Compostos de Tungstênio/químicaRESUMO
Objectives: The collateral circulation near the cerebral artery occlusion can contribute to the relief of the symptoms and signs of stroke. Genetic factors play a decisive role in the difference in collateral circulation. Survivin, encoded by the baculoviral inhibitor of apoptosis (IAP) repeat-containing 5 gene (BIRC5), plays an important role in maintaining long-term endothelial integrity and homeostasis and as an angiogenic factor in the treatment of vascular diseases. We hypothesized that genetic variations in the BIRC5 gene may contribute to severity by influencing the collateral circulation. This study aimed at examining how the polymorphism of the BIRC5 gene correlated with the collateral circulation and severity of large artery atherosclerotic stroke. Methods: This study enrolled 428 patients with large artery atherosclerotic stroke. There are no statistical differences in age, sex, social behavior, such as smoking and drinking, between the groups classified by the collateral circulation and by the severity of stroke (P > 0.01). Direct sequencing was performed for the genotyping of single nucleotide polymorphism (SNP) of BIRC5 (rs2071214). The enrolled patients were divided into several subgroups based on the collateral flow grading system from the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR), the results of the National Institutes of Health Stroke Survey (NIHSS) (6 as a threshold), and the score of the modified Rankin scale (mRS) (for the prediction of prognosis, 2 as a threshold). Differences among subgroups were identified through logistic regression. Results: The analysis of collateral circulation revealed the significant correlation of SNP of rs2071214 with the development of poor collateral circulation of large artery atherosclerotic stroke in the additive model (GG vs. AA, odds ratio (OR) = 3.592, 95% confidence interval (CI) = 1.410-9.150, and P=0.007) and the recessive model (GG vs. AA/GA, OR = 3.313, 95% CI = 1.420-7.727, and P=0.006). The analysis of stroke severity exposed the significant role of the SNP of rs2071214 in increasing stroke severity in the dominant model (GA/GG vs. AA, OR = 1.658, 95% CI = 1.017-2.703, and P=0.043) and the additive model (GA vs. AA, OR = 1.717, 95% CI = 1.021-2.888, and P=0.042). However, the analysis of the short-term outcome indicated that three genetic models were not associated with short-term outcomes in the additive model (GA vs. AA, P=0.815, GG vs. AA, and P=0.336), the dominant model (GA/GG vs. AA and P=0.589), and the recessive model (GG vs. AA/GA and P=0.342). Conclusion: Our findings identified the SNP of rs2071214 of the BIRC5 gene as a risk factor for the poor compensatory ability of collateral circulation and a predictor of stroke severity in large artery atherosclerotic stroke, which suggested that the SNP of rs2071214 can serve as an innovative therapeutic target for patients with acute ischemic stroke.
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Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Artérias , Circulação Colateral , Humanos , Polimorfismo de Nucleotídeo Único/genética , Acidente Vascular Cerebral/genética , Survivina/genéticaRESUMO
Nanoscale metal-organic frameworks (NMOFs) have proven to be a class of promising drug carriers as a result of their high porosity, crystalline nature with definite structure information, and potential for further functionality. However, MOF-based drug carriers with active tumor-targeting function have not been extensively researched until now. Here we show a strategy for constructing active tumor-targeted NMOF drug carriers by anchoring functional folic acid (FA) molecules onto the metal clusters of NMOFs. Two zirconium-based MOFs, MOF-808 and NH2 -UiO-66, were chosen as models to reduce to the nanoscale for application as drug carriers, and then the terminal carboxylates of FA molecules were coordinated to Zr6 clusters on the surfaces of the nanoparticles by substitution of the original formate or terminal -OH ligands. The successful modification with FA was confirmed by solid-state 13 C MAS NMR and UV/Vis spectroscopy and other characterization methods. Drug loading and controlled release behavior at different pH were determined by utilizing the anticancer drug 5-fluorouracil (5-FU) as the model drug. Confocal laser scanning microscopy measurements further demonstrated that 5-FU-loaded FA-NMOFs have excellent targeting ability through the efficient cellular uptake of FA-NMOFs. This work opens up a new avenue to the construction of active tumor-targeted NMOF-based drug carriers with potential for cancer therapies.
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Antineoplásicos/química , Portadores de Fármacos/química , Estruturas Metalorgânicas/química , Zircônio/química , Animais , Antineoplásicos/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Fluoruracila/química , Fluoruracila/farmacologia , Ácido Fólico/química , Células HeLa , Humanos , Camundongos , Microscopia ConfocalRESUMO
The low reactive oxygen species production capability and the shallow tissue penetration of excited light (UV) are still two barriers in photodynamic therapy (PDT). Here, Au cluster anchored black anatase TiO2-x nanotubes (abbreviated as Au25 /B-TiO2-x NTs) are synthesized by gaseous reduction of anatase TiO2 NTs and subsequent deposition of noble metal. The Au25 /B-TiO2-x NTs with thickness of about 2 nm exhibit excellent PDT performance. The reduction process increased the density of Ti3+ on the surface of TiO2 , which effectively depresses the recombination of electron and hole. Furthermore, after modification of Au25 nanoclusters, the PDT efficiency is further enhanced owing to the changed electrical distribution in the composite, which forms a shallow potential well on the metal-TiO2 interface to further hamper the recombination of electron and hole. Especially, the reduction of anatase TiO2 can expend the light response range (UV) of TiO2 to the visible and even near infrared (NIR) light region with high tissue penetration depth. When excited by NIR light, the nanoplatform shows markedly improved therapeutic efficacy attributed to the photocatalytic synergistic effect, and promotes separation or restrained recombination of electron and hole, which is verified by experimental results in vitro and in vivo.
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Ouro/química , Raios Infravermelhos , Nanopartículas/química , Nanotubos/química , Fotoquimioterapia , Titânio/química , Animais , Antineoplásicos/farmacologia , Catálise , Células HeLa , Hemólise/efeitos dos fármacos , Humanos , Camundongos , Nanopartículas/ultraestrutura , Espectrofotometria UltravioletaRESUMO
A series of hollow and luminescent capsules have been fabricated by covering luminescent Gd2O3:Yb/Tm nanoparticles on the surface of uniform hollow mesoporous silica capsules (HMSCs), which were obtained from an etching process using Fe3O4 as hard templates. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), up-conversion (UC) fluorescence spectra, and N2 adsorption-desorption were used to characterize these samples. It is found that the as-prepared products have mesoporous pores, large specific surface, and high dispersity. In particular, the size, shape, surface area, and interior space of the composites can be finely tuned by adjusting the size and morphology of the magnetic cores. Under 980 nm near-infrared (NIR) laser irradiation, the composites show characteristic blue UC emissions of Tm(3+) even after carrying doxorubicin hydrochloride (DOX). The drug-release test reveals that the capsules showed an apparent sustained release character and released in a pH-sensitive manner. Interestingly, the UC luminescence intensity of the drug-carrying system increases with the released DOX, realizing the possibility to track or monitor the released drug by the change of UC fluorescence simultaneously, which should be highly promising in anticancer drug delivery and targeted cancer therapy.
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Doxorrubicina/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Gadolínio/química , Dióxido de Silício/química , Túlio/química , Itérbio/química , Antibióticos Antineoplásicos/química , Luminescência , Nanopartículas/química , Tamanho da Partícula , Porosidade , Propriedades de SuperfícieRESUMO
Sono-photodynamic therapy is hindered by the limited tissue penetration depth of the external light source and the quick recombination of electron-hole owing to the random movement of charge carriers. In this study, orthorhombic ZnSnO3 quantum dots (QDs) with piezo-photoelectronic effects are successfully encapsulated in hexagonal upconversion nanoparticles (UCNPs) using a one-pot thermal decomposition method to form an all-in-one watermelon-like structured sono-photosensitizer (ZnSnO3 @UCNPs). The excited near-infrared light has high penetration depth, and the watermelon-like structure allows for full contact between the UCNPs and ZnSnO3 QDs, achieving ultrahigh Förster resonance energy transfer efficiency of up to 80.30%. Upon ultrasonic and near-infrared laser co-activation, the high temperature and pressure generated lead to the deformation of the UCNPs, thereby driving the deformation of all ZnSnO3 QDs inside the UCNPs, forming many small internal electric fields similar to isotropic electric domains. This piezoelectric effect not only increases the internal electric field intensity of the entire material but also prevents random movement and rapid recombination of charge carriers, thereby achieving satisfactory piezocatalytic performance. By combining the photodynamic effect arising from the energy transfer from UCNPs to ZnSnO3 , synergistic efficacy is realized. This study proposes a novel strategy for designing highly efficient sono-photosensitizers through structural design.
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Fotoquimioterapia , Fármacos Fotossensibilizantes , Eletricidade , Transferência Ressonante de Energia de Fluorescência , Raios InfravermelhosRESUMO
Platinum-based catalysts exhibit outstanding electrocatalytic performance in the hydrogen evolution reaction (HER). However, platinum-based catalysts face significant challenges due to their rarity and high cost. This paper endeavors to shed light on a promising alternative: polyoxometalate (POM)-based catalysts, which possess significant potential for the synthesis of non-noble metal-based catalysts for the HER. Utilizing POMs as raw materials to assemble POM-derived materials, including POM-derived crystalline materials, metal sulfides, phosphides, carbides, nitrides, and so on, has emerged as an effective approach for the synthesis of hydrogen evolution electrocatalysts. This approach offers advantages in both stability and electrocatalytic performance. This comprehensive review navigates through latest progress in the assembly strategy and HER performance of POM-based crystal materials, alongside discussion on transition metal compounds derived from POMs, such as carbides, phosphides, and sulfides. Besides, future developments in POM-derived electrocatalyst regulation of the electrochemical HER are prospected.
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Foreseen as foundational in forthcoming oncology interventions are multimodal therapeutic systems. Nevertheless, the tumor microenvironment (TME), marked by heightened glucose levels, hypoxia, and scant concentrations of endogenous hydrogen peroxide could potentially impair their effectiveness. In this research, two-dimensional (2D) Ti3C2 MXene nanosheets are engineered with CeO2 nanozymes and glucose oxidase (GOD), optimizing them for TME, specifically targeting cancer therapy. Following our therapeutic design, CeO2 nanozymes, embodying both peroxidase-like and catalase-like characteristics, enable transformation of H2O2 into hydroxyl radicals for catalytic therapy while also producing oxygen to mitigate hypoxia. Concurrently, GOD metabolizes glucose, thereby augmenting H2O2 levels and disrupting the intracellular energy supply. When subjected to a near-infrared laser, 2D Ti3C2 MXene accomplishes photothermal therapy (PTT) and photodynamic therapy (PDT), additionally amplifying cascade catalytic treatment via thermal enhancement. Empirical evidence demonstrates robust tumor suppression both in vitro and in vivo by the CeO2/Ti3C2-PEG-GOD nanocomposite. Consequently, this integrated approach, which combines PTT/PDT and enzymatic catalysis, could offer a valuable blueprint for the development of advanced oncology therapies.
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Hipertermia Induzida , Neoplasias , Nitritos , Elementos de Transição , Humanos , Glucose Oxidase , Peróxido de Hidrogênio , Titânio/farmacologia , Hipertermia , Neoplasias/terapia , Glucose , Hipóxia , Microambiente Tumoral , Linhagem Celular TumoralRESUMO
Heteroatom doping and phase engineering are effective ways to promote the catalytic activity of nanoenzymes. Nitrogen-doped 1 T/2H mixed phase MoS2/CuS heterostructure nanosheets N-1 T/2H-MoS2/CuS are prepared by a simple hydrothermal approach using polyoxometalate (POM)-based metal-organic frameworks (MOFs) (NENU-5) as a precursor and urea as nitrogen doping reagent. The XPS spectroscopy (XPS) and Raman spectrum of N-1 T/2H-MoS2/CuS prove the successful N-doping. NENU-5 was used as the template to prepare 1 T/2H-MoS2/CuS with high content of 1 T phase by optimizing the reaction time. The use of urea as nitrogen dopant added to 1 T/2H-MoS2/CuS, resulted in N-1 T/2H-MoS2/CuS with an increase in the content of the 1 T phase from 80 % to 84 % and higher number of defects. N-1 T/2H-MoS2/CuS shows higher peroxidase activity than 1 T/2H-MoS2/CuS and a catalytic efficiency (Kcat/Km) for H2O2 twice as high as that of 1 T/2H-MoS2/CuS. The enhanced catalytic activity has probably been attributed to several reasons: (i) the insertion of urea during the hydrothermal process in the S-Mo-S layer of MoS2, causing an increase in the interlayer spacing and in 1 T phase content, (ii) the replacement of S atoms in MoS2 by N atoms from the urea decomposition, resulting in more defects and more active sites. As far as we know, N-1 T/2H-MoS2/CuS nanosheets have the lowest detection limit (0.16 µm) for the colorimetric detection of hydroquinone among molybdenum disulfide-based catalysts. This study affords a new approach for the fabrication of high-performance nanoenzyme catalysts.
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MoS2-based materials have emerged as photoelectric semiconductors characterized by a narrow band gap, high capacity for absorbing visible light, and reduced H2 adsorption energy comparable to Pt. These attributes render them appealing for application in photocatalytic hydrogen production. Despite these advantages, the widespread adoption of MoS2-based materials remains hindered by challenges associated with limited exposure to active sites and suboptimal catalytic hydrogen production efficiency. To address these issues, we have designed and synthesized a new class of highly dispersed bimetallic/trimetallic sulfide materials. This was achieved by developing polyoxometalate synthons containing Ni-Mo elements, which were subsequently reacted with thiourea and CdS. The resulting Ni3S2-MoS2 and Ni3S2-MoS2-CdS materials achieve photocatalytic hydrogen production rates of 2770 and 2873 µmol g-1h-1, respectively. Notably, the rate of 2873 µmol g-1h-1 for Ni3S2-MoS2-CdS surpassed triple (3.23 times) the performance of CdS and nearly sextuple (5.77 times) that of single MoS2. These materials outperformed the majority of MoS2-based photocatalysts. Overall, this study introduces a straightforward methodology for synthesizing bimetallic/trimetallic sulfides with enhanced photocatalytic H2 evolution performance. Our findings underscore the potential of transition metal sulfide semiconductors in the realm of photocatalysis and pave the way for the development of more sustainable energy production systems.
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This study was performed to detect the expression of ceruloplasmin in the peripheral blood of patients with drug-resistant epilepsy and explore the mechanisms of iron metabolism disorder in drug-resistant epilepsy. Peripheral blood was collected from 32 patients with drug-resistant epilepsy, labeled the drug-resistant group; 30 patients who were drug responsive, labeled the drug-responsive group; and 34 healthy people, named the normal group.The expression levels of ceruloplasmin mRNA and ceruloplasmin protein in the peripheral blood of the 3 groups were detected using real-time fluorescence-based quantitative polymerase chain reaction and Western blot. The differences in the expression of ceruloplasmin mRNA of different seizure frequencies and types, electroencephalogram abnormal discharges, and different medication methods were analyzed and compared. The relative expression of ceruloplasmin mRNA and ceruloplasmin protein in the drug-resistant epilepsy group was significantly higher than that in the drug-responsive group (P = .002 and .010, respectively) and higher in the drug-responsive group compared with the normal group (P = .014 and .005, respectively). The relative expression of ceruloplasmin mRNA in patients with epilepsy using different medication methods was statistically significant (P = .001). Patients who received a combination of 2 or 3 drugs exhibited a higher expression than those treated with single-drug treatment, whereas those who received a combination of 3 drugs had a higher expression than those with 2 drugs (P = .013, .001, and .011, respectively). There was no significant difference in the relative expression of Cp mRNA in patients with epilepsy with different seizure frequencies and types and abnormal electroencephalogram discharges (all P > .05). The increased expression of ceruloplasmin in the peripheral blood of patients with drug-resistant epilepsy was closely related to the different medication methods, but no obvious correlation with epileptic seizure frequencies or types and abnormal electroencephalogram discharges was identified. The increased expression of ceruloplasmin enhanced iron oxidative damage and may be the potential mechanism of drug-resistant epilepsy and may be one of the drug resistance indicators for combination drugs when treating drug-resistant epilepsy.
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Epilepsia Resistente a Medicamentos , Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Epilepsia Resistente a Medicamentos/diagnóstico , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Ceruloplasmina/análise , Ceruloplasmina/genética , Regulação da Expressão Gênica , Estresse Oxidativo , Convulsões , Gravidade do Paciente , EletroencefalografiaRESUMO
Since the discovery of enzyme-like activity of Fe3O4 nanoparticles in 2007, nanozymes are becoming the promising substitutes for natural enzymes due to their advantages of high catalytic activity, low cost, mild reaction conditions, good stability, and suitable for large-scale production. Recently, with the cross fusion of nanomedicine and nanocatalysis, nanozyme-based theranostic strategies attract great attention, since the enzymatic reactions can be triggered in the tumor microenvironment to achieve good curative effect with substrate specificity and low side effects. Thus, various nanozymes have been developed and used for tumor therapy. In this review, more than 270 research articles are discussed systematically to present progress in the past five years. First, the discovery and development of nanozymes are summarized. Second, classification and catalytic mechanism of nanozymes are discussed. Third, activity prediction and rational design of nanozymes are focused by highlighting the methods of density functional theory, machine learning, biomimetic and chemical design. Then, synergistic theranostic strategy of nanozymes are introduced. Finally, current challenges and future prospects of nanozymes used for tumor theranostic are outlined, including selectivity, biosafety, repeatability and stability, in-depth catalytic mechanism, predicting and evaluating activities.
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The hydrogen evolution reaction (HER) is important for "green" hydrogen production from water electrolysis. Nowadays, there is an urgent need to construct highly efficient electrocatalysts to boost the HER and achieve hydrogen production. Herein, we present the preparation of a new composite Co-Mo bimetallic sulfide supported on carbon cloth (MoS2/CoS2/CC) via a one-pot hydrothermal sulfurization strategy using (C3H5N2)6[CoMo12O40]·10H2O (CoMo12) as a metal source and thiourea as a sulfur source. The obtained MoS2/CoS2/CC catalyst exhibited outstanding HER ability, with an overpotential of 69 mV when the current density is 10 mA cm-2 in KOH solution, showing comparable performance with those of the advanced Pt/C electrodes tested under the same conditions. Additionally, the results of XRD after the catalytic reaction showed that the electrode had excellent stability in the electrolyte of 1.0 M KOH.
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The development of photocatalysts toward highly efficient H2 evolution reactions is a feasible strategy to achieve the effective conversion of solar energy and meet the increasing demand for new energy. To this end, we prepared two different CdS-MoS2 photocatalysts with unique morphologies ranging from hexagonal prisms to tetragonal nanotubes by carefully tuning polyoxometalate synthons. These two photocatalysts, namely, CdS-MoS2-1 and CdS-MoS2-2, both exhibited remarkable photocatalytic efficiency in H2 generation, among which CdS-MoS2-2 showed superior performance. In fact, the best catalytic hydrogen desorption rate of CdS-MoS2-2 is as high as 1815.5 µmol g-1 h-1. Such performance is superior to twice that of single CdS and almost four times that of pure MoS2. This obvious enhancement can be accredited to the highly open nanotube morphology and highly dispersed heterometallic composition of CdS-MoS2-2, which represents an excellent example of the highest noble-metal-free H2 evolution photocatalysts reported so far. Taken together, these findings suggest that the development of highly dispersed heterometallic catalysts is an auspicious route to realize highly efficient conversion of solar energy and that CdS-MoS2-2 represents a major advance in this field.
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There is an urgent need to develop photosensitive nanoenzymes with better phototherapeutic efficiency through simple processes. By exploiting semiconductor catalysis and defect chemistry principles, herein, a MnMoOx composite semiconductor nanoenzyme was developed to achieve a fully integrated theranostic nanoenzyme for highly efficient photo/chemo-enzyme-dynamic eradication of deep tumors. Relative to iron oxides, manganese oxides offer ideal catalytic performance under near-neutral conditions, which helps to broaden the suitable pH range of the MnMoOx nanoenzyme for antitumor therapy. Furthermore, with the assistance of glutathione depletion, Mn4+/Mo6+ was successfully converted to Mn2+/Mo5+, inhibiting the scavenging of reactive oxygen species (ROS) and promoting cycling. Therefore, MnMoOx has favorable catalase (CAT)-like activity and oxidase (OXD)-like activity in the tumor microenvironment (TME) for promoting the "H2O2O2O2-" and "H2O2OH" cascade reactions. The abundant oxygen vacancy defects also promote the surface plasmon resonance (SPR) effect in the second near-infrared (NIR-II) window of MnMoOx, which significantly enhanced its photothermal therapy (PTT) effect and catalytic activity. In detail, ROS production was significantly enhanced due to the adsorption of water and oxygen molecules by the rich oxygen vacancies of MnMoOx. MnMoOx also exhibited excellent multi-modal imaging activity (including computed tomography (CT), magnetic resonance imaging (MRI), and photoacoustic (PA)), which can be exploited to better guide the administration of medication.
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Nanopartículas , Neoplasias , Catálise , Linhagem Celular Tumoral , Humanos , Nanopartículas/química , Neoplasias/terapia , Óxidos/química , Oxigênio/química , Espécies Reativas de Oxigênio , Microambiente TumoralRESUMO
Aim: The authors aimed to investigate whether polymorphisms of PON-1 were associated with the susceptibility to and severity of ischemic stroke (IS). Methods: In this study, 302 IS patients and 303 healthy controls were enrolled. Polymorphisms rs854560 and rs854572 of PON-1 were detected using SNaPshot single-nucleotide polymorphism typing technology. Results: The rs854572 polymorphism of the PON-1 gene showed a significant correlation with IS, and its GG genotype reduced the risk of IS (recessive model, p = 0.001). The GG genotype was also associated with mild stroke (p = 0.032). No association was observed between rs854560 and IS. Conclusion:PON-1 rs854572 polymorphism was related to the risk of IS and could be a biomarker to access the severity of IS.
Ischemic stroke is a common cerebrovascular disease and genetic factors play an important role in its pathogenesis and progression. PON-1 is an enzyme involved in blood lipid metabolism, and previous studies have found that the PON-1 gene is related to coronary heart disease and other atherosclerotic diseases, while the correlation between PON-1 polymorphism and ischemic stroke remains unclear. The authors compared PON-1 polymorphism between patients with acute ischemic stroke and healthy adults and further investigated the relationship between the PON-1 polymorphism and the severity of ischemic stroke. It was found that PON-1 polymorphism rs854572 was related to the susceptibility to ischemic stroke and the severity of the disease, suggesting that people with risk genotypes should take more active preventive and therapeutic measures.
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Arildialquilfosfatase/genética , AVC Isquêmico , Povo Asiático/genética , China , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
Highly efficient catalysts with enough selectivity and stability are essential for electrochemical nitrogen reduction reaction (e-NRR) that has been considered as a green and sustainable route for synthesis of NH3. In this work, a series of three-dimensional (3D) porous iron foam (abbreviated as IF) self-supported FeS2-MoS2 bimetallic hybrid materials, denoted as FeS2-MoS2@IFx, x = 100, 200, 300, and 400, were designed and synthesized and then directly used as the electrode for the NRR. Interestingly, the IF serving as a slow-releasing iron source together with polyoxomolybdates (NH4)6Mo7O24·4H2O as a Mo source were sulfurized in the presence of thiourea to form self-supported FeS2-MoS2 on IF (abbreviated as FeS2-MoS2@IF200) as an efficient electrocatalyst. Further material characterizations of FeS2-MoS2@IF200 show that flower cluster-like FeS2-MoS2 grows on the 3D skeleton of IF, consisting of interconnected and staggered nanosheets with mesoporous structures. The unique 3D porous structure of FeS2-MoS2@IF together with synergy and interface interactions of bimetallic sulfides would make FeS2-MoS2@IF possess favorable electron transfer tunnels and expose abundant intrinsic active sites in the e-NRR. It is confirmed that synthesized FeS2-MoS2@IF200 shows a remarkable NH3 production rate of 7.1 ×10-10 mol s-1 cm-2 at -0.5 V versus the reversible hydrogen electrode (vs RHE) and an optimal faradaic efficiency of 4.6% at -0.3 V (vs RHE) with outstanding electrochemical and structural stability.
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Integration of various therapeutic modes and novel hypoxic therapy are two emerging aspects in the current anti-cancer field. Based on this, we designed a multifunctional therapeutic system combining photothermal therapy (PTT), the newly defined chemodynamic therapy (CDT) and AIPH-based hypoxic therapy ingeniously, which can take effect well in hypoxic tumor environments. The CuFeSe2-based heterojunction was controllably constructed by the coating of a MIL-100(Fe) shell layer by layer, and the large mesoporous cavities were subsequently filled with a polymerization initiator (AIPH) and phase change material (tetradecanol) to achieve higher drug loading and controlled heat release of radicals. When irradiated by a single 808 nm laser, the photothermal agent of CuFeSe2 plays a significant role of the initiating switch in the whole nanoplatform, whose hyperthermia not only realizes fundamental PTT but also promotes greatly the Fenton reaction of the MIL-100(Fe) shell for oxidative ËOH production and the generation of toxic AIPH radicals while melting tetradecanol. Due to the sensitive heat-responsive therapies independent of oxygen concentration, the nanoplatform showed a superior therapeutic effect for hypoxic tumor environments. Besides, on account of the effective attenuation for X-rays and the presence of the magnetic element Fe of CuFeSe2, the nanoplatform was also certified to be a superior diagnosis agent for computed tomography (CT) and magnetic resonance imaging (MRI). As expected, cell experiments in vitro and mice experiments in vivo further verified the excellent biocompatibility and antitumor effect, suggesting that this nanoplatform of CuFeSe2@MIL-100(Fe)-AIPH is promising for simultaneous diagnosis and treatment in hypoxic cancer therapy.