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1.
Nano Lett ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38620050

RESUMEN

Understanding the structure-performance relationships of a frustrated Lewis pair (FLP) at the atomic level is key to yielding high efficiency in activating chemically "inert" molecules into value-added products. A sound strategy was developed herein through incorporating oxygen defects into a Zr-based metal-organic layer (Zr-MOL-D) and employing Lewis basic proximal surface hydroxyls for the in situ formation of solid heterogeneous FLP (Zr4-δ-VO-Zr-OH). Zr-MOL-D exhibits a superior CO2 to CO conversion rate of 49.4 µmol g-1 h-1 in water vapor without any sacrificing agent or photosensitizer, which is about 12 times higher than that of pure MOL (Zr-MOL-P), with extreme stability even after being placed for half a year. Theoretical and experimental results reveal that the introduction of FLP converts the process of the crucial intermediate COOH* from an endothermic reaction to an exothermic spontaneous reaction. This work is expected to provide new prospects for developing efficient MOL-based photocatalysts in FLP chemistry through a sound defect-engineering strategy.

2.
J Am Chem Soc ; 146(11): 7467-7479, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38446421

RESUMEN

Interfacial interaction dictates the overall catalytic performance and catalytic behavior rules of the composite catalyst. However, understanding of interfacial active sites at the microscopic scale is still limited. Importantly, identifying the dynamic action mechanism of the "real" active site at the interface necessitates nanoscale, high spatial-time-resolved complementary-operando techniques. In this work, a Co3O4 homojunction with a well-defined interface effect is developed as a model system to explore the spatial-correlation dynamic response of the interface toward oxygen evolution reaction. Quasi in situ scanning transmission electron microscopy-electron energy-loss spectroscopy with high spatial resolution visually confirms the size characteristics of the interface effect in the spatial dimension, showing that the activation of active sites originates from strong interfacial electron interactions at a scale of 3 nm. Multiple time-resolved operando spectroscopy techniques explicitly capture dynamic changes in the adsorption behavior for key reaction intermediates. Combined with density functional theory calculations, we reveal that the dynamic adjustment of multiple adsorption configurations of intermediates by highly activated active sites at the interface facilitates the O-O coupling and *OOH deprotonation processes. The dual dynamic regulation mechanism accelerates the kinetics of oxygen evolution and serves as a pivotal factor in promoting the oxygen evolution activity of the composite structure. The resulting composite catalyst (Co-B@Co3O4/Co3O4 NSs) exhibits an approximately 70-fold turnover frequency and 20-fold mass activity than the monomer structure (Co3O4 NSs) and leads to significant activity (η10 ∼257 mV). The visual complementary analysis of multimodal operando/in situ techniques provides us with a powerful platform to advance our fundamental understanding of interfacial structure-activity relationships in composite structured catalysts.

3.
Anal Chem ; 96(21): 8772-8781, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38743842

RESUMEN

The metabolic signature identification of colorectal cancer is critical for its early diagnosis and therapeutic approaches that will significantly block cancer progression and improve patient survival. Here, we combined an untargeted metabolic analysis strategy based on internal extractive electrospray ionization mass spectrometry and the machine learning approach to analyze metabolites in 173 pairs of cancer samples and matched normal tissue samples to build robust metabolic signature models for diagnostic purposes. Screening and independent validation of metabolic signatures from colorectal cancers via machine learning methods (Logistic Regression_L1 for feature selection and eXtreme Gradient Boosting for classification) was performed to generate a panel of seven signatures with good diagnostic performance (the accuracy of 87.74%, sensitivity of 85.82%, and specificity of 89.66%). Moreover, seven signatures were evaluated according to their ability to distinguish between cancer and normal tissues, with the metabolic molecule PC (30:0) showing good diagnostic performance. In addition, genes associated with PC (30:0) were identified by multiomics analysis (combining metabolic data with transcriptomic data analysis) and our results showed that PC (30:0) could promote the proliferation of colorectal cancer cell SW480, revealing the correlation between genetic changes and metabolic dysregulation in cancer. Overall, our results reveal potential determinants affecting metabolite dysregulation, paving the way for a mechanistic understanding of altered tissue metabolites in colorectal cancer and design interventions for manipulating the levels of circulating metabolites.


Asunto(s)
Neoplasias Colorrectales , Aprendizaje Automático , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/diagnóstico , Humanos , Metabolómica , Línea Celular Tumoral , Espectrometría de Masa por Ionización de Electrospray , Metaboloma , Proliferación Celular , Multiómica
4.
Small ; 20(24): e2309937, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38178644

RESUMEN

High entropy materials offer almost unlimited catalytic possibilities due to their variable composition, unique structure, and excellent electrocatalytic performance. However, due to the strong tendency of nanoparticles to coarsen and agglomerate, it is still a challenge to synthesize nanoparticles using simple methods to precisely control the morphology and size of the nanoparticles in large quantities, and their large-scale application is limited by high costs and low yields. Herein, a series of high-entropy oxides (HEOs) nanoparticles with high-density and ultrasmall size (<5 nm) loaded on carbon nanosheets with large quantities are prepared by Joule-heating treatment of gel precursors in a short period of time (≈60 s). Among them, the prepared (FeCoNiRuMn)3O4-x catalyst shows the best electrocatalytic activity for oxygen evolution reaction, with low overpotentials (230 mV @10 mA cm-2, 270 mV @100 mA cm-2), small Tafel slope (39.4 mV dec-1), and excellent stability without significant decay at 100 mA cm-2 after 100 h. The excellent performance of (FeCoNiRuMn)3O4-x can be attributed to the synergistic effect of multiple elements and the inherent structural stability of high entropy systems. This study provides a more comprehensive design idea for the preparation of efficient and stable high entropy catalysts.

5.
Small ; 20(22): e2310266, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38098346

RESUMEN

The interactions between the catalyst and support are widely used in many important catalytic reactions but the construction of strong interaction with definite microenvironments to understand the structure-activity relationship is still challenging. Here, strongly-interacted composites are prepared via selective exsolution of active NiSe2 from the host matrix of NiFe2O4 (S-NiSe2/NiFe2O4) taking advantage of the differences of migration energy, in which the NiSe2 possessed both high dispersion and small size. The characteristics of spatially resolved scanning transmission X-ray microscopy (STXM) coupled with analytical Mössbauer spectra for the surface and bulk electronic structures unveiled that this strongly interacted composite triggered more charge transfers from the NiSe2 to the host of NiFe2O4 while stabilizing the inherent atomic coordination of NiFe2O4. The obtained S-NiSe2/NiFe2O4 exhibits overpotentials of 290 mV at 10 mA cm-2 for oxygen evolution reaction (OER). This strategy is general and can be extended to other supported catalysts, providing a powerful tool for modulating the catalytic performance of strongly-interacted composites.

6.
Angew Chem Int Ed Engl ; : e202410734, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958047

RESUMEN

Since the discovery in 2000, conversion-type materials have emerged as a promising negative-electrode candidate for next-generation batteries with high capacity and tunable voltage, limited by low reversibility and severe voltage hysteresis. Heterogeneous construction stands out as a cost-effective and efficient approach to reducing reaction barriers and enhancing energy density. However, the second term introduced by conventional heterostructure inevitably complicates the electrochemical analysis and poses great challenges to harvesting systematic insights and theoretical guidance. A model cell is designed and established herein for the conversion reactions between Na and TMSA-SnO2, where TMSA-SnO2 represents single atom modification of eight different 3d transition elements (V, Cr, Mn, Fe, Co, Ni, Cu or Zn). Such a model unit fundamentally eliminates the interference from the second phase and thus enables independent exploration of activation manifestations of the heterogeneous architecture. For the first time, a thermodynamically dependent catalytic effect is proposed and verified through statistical data analysis. The mechanism behind the unveiled catalytic effect is further elucidated by which the active d orbitals of transition metals weaken the surface covalent bonds and lower the reaction barriers. This research provides both theoretical insights and practical demonstrations of the advanced heterogeneous electrodes.

7.
Angew Chem Int Ed Engl ; : e202406711, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38923764

RESUMEN

Spin state is often regarded as the crucial valve to release the reactivity of energy-related catalysts, yet it is also challenging to precisely manipulate, especially for the active center ions occupied at the specific geometric sites. Herein, a π-π type orbital coupling of 3d (Co)-2p (O)-4f (Ce) was employed to regulate the spin state of octahedral cobalt sites (CoOh) in the composite of Co3O4/CeO2. More specifically, the equivalent high-spin ratio of CoOh can reach to 54.7% via tuning the CeO2 content, thereby triggering the average eg filling (1.094) close to the theoretical optimum value. The corresponding catalyst exhibits a superior water oxidation performance with an overpotential of 251 mV at 10 mA cm-2, rivaling most cobalt-based oxides state-of-the-art. The π-π type coupling corroborated by the matched energy levels between Ce t1u/t2u-O and CoOh t2g-O π type bond in the calculated crystal orbital Hamilton population and partial density of states profiles, stimulates a π-donation between O 2p and π-symmetric Ce 4fyz2 orbital, consequently facilitating the electrons hopping from t2g to eg orbital of CoOh. This work offers an in-depth insight into understanding the 4f and 3d orbital coupling for spin state optimization in composite oxides.

8.
J Am Chem Soc ; 145(31): 17309-17320, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37525440

RESUMEN

Organic materials are promising for cation storage in calcium ion batteries (CIBs). However, the high solubility of organic materials in an electrolyte and low electronic conductivity remain the key challenges for high-performance CIBs. Herein, a nitrogen-rich covalent organic framework with multiple carbonyls (TB-COF) is designed as an aqueous anode to address those obstacles. TB-COF demonstrates a high reversible capacity of 253 mAh g-1 at 1.0 A g-1 and long cycle life (0.01% capacity decay per cycle at 5 A g-1 after 3000 cycles). The redox mechanism of Ca2+/H+ co-intercalated in COF and chelating with C═O and C═N active sites is validated. In addition, a novel C═C active site was identified for Ca2+ ion storage. Both computational and empirical results reveal that per TB-COF repetitive unit, up to nine Ca2+ ions are stored after three staggered intercalation steps, involving three distinct Ca2+ ion storage sites. Finally, the evolution process of radical intermediates further elucidates the C═C reaction mechanism.

9.
Small ; 19(33): e2301436, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37078904

RESUMEN

The development of fast charging materials offers a viable solution for large-scale and sustainable energy storage needs. However, it remains a critical challenge to improve the electrical and ionic conductivity for better performance. Topological insulator (TI), a topological quantum material that has attracted worldwide attention, hosts unusual metallic surface states and consequent high carrier mobility. Nevertheless, its potential in promising high-rate charging capability has not been fully realized and explored. Herein, a novel Bi2 Se3 -ZnSe heterostructure as excellent fast charging material for Na+ storage is reported. Ultrathin Bi2 Se3 nanoplates with rich TI metallic surfaces are introduced as an electronic platform inside the material, which greatly reduces the charge transfer resistance and improves the overall electrical conductivity. Meanwhile, the abundant crystalline interfaces between these two selenides promote Na+ migration and provide additional active sites as well. As expected, the composite delivers the excellent high-rate performance of 360.5 mAh g-1 at 20 A g-1 and maintains its electrochemical stability of 318.4 mAh g-1 after 3000 long cycles, which is the record high for all reported selenide-based anodes. This work is anticipated to provide alternative strategies for further exploration of topological insulators and advanced heterostructures.

10.
BMC Vet Res ; 19(1): 14, 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36658569

RESUMEN

BACKGROUND: Classical swine fever and porcine reproductive and respiratory syndrome have seriously affected the development of the swine breeding industry in China. Vaccine immunization remains the main way to prevent these infections. The aim of this study was to establish an optimized protocol for vaccine immunization against classical swine fever virus (CSFV) and porcine reproductive and respiratory syndrome virus (PRRSV). METHODS: Blood samples were collected from the anterior vena cava of pigs after immunization, and blood indices, secreted levels of specific antibodies and neutralizing antibodies associated with humoral immunity, the proliferation capacity of T lymphocytes as a measure of cellular immunity, and secreted levels of IFN-γ and TNF-α were determined. RESULTS: The results showed that simultaneous immunization against CSFV and PRRSV infections induced strong and specific humoral and T-cellular immune responses, high levels of cytokine IFN-γ secretion and delayed secretion of cytokine TNF-α. Moreover, significantly higher lymphocyte percentages and red blood cell and leukocyte counts were found in the group simultaneously immunized against CSFV and PRRSV. However, no statistically significant differences were observed in hemoglobin values, neutrophil counts, and median cell percentages among the S + PRRS, PRRS-S, and S-PRRS groups. CONCLUSION: This study demonstrated that simultaneous immunization against CSFV and PRRSV had the advantages of inducing a rapid, enhanced, and long-lasting immune response. These findings provide a theoretical basis for the establishment of a reasonable and optimized vaccine immunization protocol against CSFV and PRRSV in combination with a variety of other vaccine inoculations.


Asunto(s)
Peste Porcina Clásica , Síndrome Respiratorio y de la Reproducción Porcina , Enfermedades de los Porcinos , Vacunas Virales , Animales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Peste Porcina Clásica/prevención & control , Virus de la Fiebre Porcina Clásica , Citocinas , Síndrome Respiratorio y de la Reproducción Porcina/prevención & control , Virus del Síndrome Respiratorio y Reproductivo Porcino , Porcinos , Enfermedades de los Porcinos/prevención & control , Factor de Necrosis Tumoral alfa , Vacunación/métodos , Vacunación/veterinaria
11.
Nano Lett ; 22(12): 4970-4978, 2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35678583

RESUMEN

The influence of defects on quantitative carrier dynamics is still unclear. Therefore, full-spectrum responsive metallic ZnIn2S4 (VIn-rich-ZIS) rich in indium vacancies and exhibiting high CO2 photoreduction efficiency was synthesized for the first time. The influence of the defects on the carrier dynamic parameters was studied quantitatively; the results showed that the minority carrier diffusion length (LD) is closely related to the catalytic performance. In situ infrared spectroscopy and theoretical calculations revealed that the presence of indium vacancies lowers the energy barrier for CO2 to CO conversion via the COOH* intermediate. Hence, the high rate of CO evolution reaches 298.0 µmol g-1 h-1, a nearly 28-fold enhancement over that with ZnIn2S4 (VIn-poor-ZIS), which is not rich in indium vacancies. This work fills the gaps between the catalytic performance of defective photocatalysts and their carrier dynamics and may offer valuable insight for understanding the mechanism of photocatalysis and designing more efficient defective photocatalysts.

12.
Molecules ; 28(2)2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36677630

RESUMEN

The African Swine Fever virus (ASFV) causes an infectious viral disease in pigs of all ages. The development of antiviral drugs primarily aimed at inhibition of proteases required for the proteolysis of viral polyproteins. In this study, the conformation of the pS273R protease in physiological states were investigated, virtually screened the multi-protein conformation of pS273R target proteins, combined various molecular docking scoring functions, and identified five potential drugs from the Food and Drug Administration drug library that may inhibit pS273R. Subsequent validation of the dynamic interactions of pS273R with the five putative inhibitors was achieved using molecular dynamics simulations and binding free energy calculations using the molecular mechanics/Poison-Boltzmann (Generalized Born) (MM/PB(GB)SA) surface area. These findings demonstrate that the arm domain and Thr159-Lys167 loop region of pS273R are significantly more flexible compared to the core structural domain, and the Thr159-Lys167 loop region can serve as a "gatekeeper" in the substrate channel. Leucovorin, Carboprost, Protirelin, Flavin Mononucleotide, and Lovastatin Acid all have Gibbs binding free energies with pS273R that were less than -20 Kcal/mol according to the MM/PBSA analyses. In contrast to pS273R in the free energy landscape, the inhibitor and drug complexes of pS273R showed distinct structural group distributions. These five drugs may be used as potential inhibitors of pS273R and may serve as future drug candidates for treating ASFV.


Asunto(s)
Virus de la Fiebre Porcina Africana , Antivirales , Inhibidores de Proteasas , Animales , Virus de la Fiebre Porcina Africana/efectos de los fármacos , Virus de la Fiebre Porcina Africana/enzimología , Endopeptidasas , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Péptido Hidrolasas , Conformación Proteica , Porcinos , Inhibidores de Proteasas/química , Inhibidores de Proteasas/farmacología , Antivirales/química , Antivirales/farmacología
13.
Molecules ; 28(3)2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36771101

RESUMEN

Identification of novel drugs for anti-African swine fever (ASF) applications is of utmost urgency, as it negatively affects pig farming and no effective vaccine or treatment is currently available. African swine fever virus (ASFV) encoded pS273R is a cysteine protease that plays an important role in virus replication. E64, acting as an inhibitor of cysteine protease, has been established as exerting an inhibitory effect on pS273R. In order to obtain a better understanding of the interaction between E64 and pS273R, common docking, restriction docking, and covalent docking were employed to analyze the optimal bonding position between pS273R-E64 and its bonding strength. Additionally, three sets of 100 ns molecular dynamics simulations were conducted to examine the conformational dynamics of pS273R and the dynamic interaction of pS273R-E64, based on a variety of analytical methods including root mean square deviation (RMSD), root mean square fluctuation (RMSF), free energy of ligand (FEL), principal component analysis (PCA), and molecular mechanics/Poisson-Boltzmann surface area (MM/PBSA) analysis. The results show that E64 and pS273R exhibited close binding degrees at the activity center of ASFV pS273R protease. The data of these simulations indicate that binding of E64 to pS273R results in a reduction in flexibility, particularly in the ARM region, and a change in the conformational space of pS273R. Additionally, the ability of E64 to interact with polar amino acids such as ASN158, SER192, and GLN229, as well as charged amino acids such as LYS167 and HIS168, seems to be an important factor in its inhibitory effect. Finally, Octet biostratigraphy confirmed the binding of E64 and pS273R with a KD value of 903 uM. Overall, these findings could potentially be utilized in the development of novel inhibitors of pS273R to address the challenges posed by ASFV.


Asunto(s)
Virus de la Fiebre Porcina Africana , Proteasas de Cisteína , Porcinos , Animales , Simulación de Dinámica Molecular , Endopeptidasas/metabolismo , Aminoácidos/metabolismo , Proteasas de Cisteína/metabolismo
14.
Angew Chem Int Ed Engl ; 62(38): e202309784, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37539978

RESUMEN

Metal single atoms (SAs) anchored in carbon support via coordinating with N atoms are efficient active sites to oxygen reduction reaction (ORR). However, rational design of single atom catalysts with highly exposed active sites is challenging and urgently desirable. Herein, an anion exchange strategy is presented to fabricate Fe-N4 moieties anchored in hierarchical carbon nanoplates composed of hollow carbon spheres (Fe-SA/N-HCS). With the coordinating O atoms are substituted by N atoms, Fe SAs with Fe-O4 configuration are transformed into the ones with Fe-N4 configuration during the thermal activation process. Insights into the evolution of central atoms demonstrate that the SAs with specific coordination environment can be obtained by modulating in situ anion exchange process. The strategy produces a large quantity of electrochemical accessible site and high utilization rate of Fe-N4 . Fe-SA/N-HCS shows excellent ORR electrocatalytic performance with half-wave potential of 0.91 V (vs. RHE) in 0.1 M KOH, and outstanding performance when used in rechargeable aqueous and flexible Zn-air batteries. The evolution pathway for SAs demonstrated in this work offers a novel strategy to design SACs with various coordination environment and enhanced electrocatalytic activity.

15.
Angew Chem Int Ed Engl ; 62(14): e202300406, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36754865

RESUMEN

Oxygen vacancies-enriched black TiO2 is one promising support for enhancing hydrogen evolution reaction (HER). Herein, oxygen vacancies enriched black TiO2 supported sub-nanometer Pt clusters (Pt/TiO2 -OV ) with metal support interactions is designed through solvent-free microwave and following low-temperature electroless approach for the first time. High-temperature and strong reductants are not required and then can avoid the aggregation of decorated Pt species. Experimental and theoretical calculation verify that the created oxygen vacancies and Pt clusters exhibit synergistic effects for optimizing the reaction kinetics. Based on it, Pt/TiO2 -OV presents remarkable electrocatalytic performance with 18 mV to achieve 10 mA cm-2 coupled with small Tafel slope of 12 mV dec-1 . This work provides quick synthetic strategy for preparing black titanium dioxide based nanomaterials.

16.
Anal Chem ; 94(34): 11821-11830, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-35976989

RESUMEN

The application of rapid and accurate diagnostic methods can improve colorectal cancer (CRC) survival rates dramatically. Here, we used a non-targeted metabolic analysis strategy based on internal extractive electrospray ionization mass spectrometry (iEESI-MS) to detect metabolite ions associated with the progression of CRC from 172 tissues (45 stage I/II CRC, 41 stage III/IV CRC, and 86 well-matched normal tissues). A support vector machine (SVM) model based on 10 differential metabolite ions for differentiating early-stage CRC from normal tissues was built with a good prediction accuracy of 92.6%. The biomarker panel consisting of lysophosphatidylcholine (LPC) (18:0) has good diagnostic potential in differentiating early-stage CRC from advanced-stage CRC. We showed that the down-regulation of LPC (18:0) in tumor tissues is associated with CRC progression and related to the regulation of the epidermal growth factor receptor. Pathway analysis showed that metabolic pathways in CRC are related to glycerophospholipid metabolism and purine metabolism. In conclusion, we built an SVM model with good performance to distinguish between early-stage CRC and normal groups based on iEESI-MS and found that LPC (18:0) is associated with the progression of CRC.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Colorrectales , Biomarcadores de Tumor/metabolismo , Neoplasias Colorrectales/patología , Regulación hacia Abajo , Humanos , Metabolismo de los Lípidos , Espectrometría de Masa por Ionización de Electrospray
17.
Small ; 18(13): e2106558, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35119204

RESUMEN

The N6-methyladenosine (m6 A) demethylase FTO plays an oncogenic role in acute myeloid leukemia (AML). Despite the promising recent progress for developing some small-molecule FTO inhibitors, the clinical potential remains limited due to mild biological function, toxic side effects and low sensitivity and/or specificity to leukemic stem cells (LSCs). Herein, FTO inhibitor-loaded GSH-bioimprinted nanocomposites (GNPIPP12MA) are developed that achieves targeting of the FTO/m6 A pathway synergized GSH depletion for enhancing anti-leukemogenesis. GNPIPP12MA can selectively target leukemia blasts, especially LSCs, and induce ferroptosis by disrupting intracellular redox status. In addition, GNPIPP12MA increases global m6 A RNA modification and decreases the transcript levels in LSCs. GNPIPP12MA augments the efficacy of the PD-L1 blockade by increasing the infiltration of cytotoxic T cells for enhanced anti-leukemia immunity. This study offers insights for a GSH-bioimprinted nanoplatform targeting m6 A RNA methylation as a synergistic treatment strategy against cancer stem cells that may translate to clinical applications.


Asunto(s)
Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato , Nanopartículas , Adenosina/análogos & derivados , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/metabolismo , Glutatión , Células Madre Neoplásicas , ARN Mensajero/genética
18.
Small ; 18(11): e2105168, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35038219

RESUMEN

Searching for Pt-like activity, stable and economic electrocatalysts that can function at various pH values for the hydrogen evolution reaction (HER) is under increasing interest for the scientific community as H2 is a very promising energy carrier with great potential development value for renewable energy conversion. Herein, a unique self-supported heterostructure of RuO2 -RuP2 /Ru on the N, P co-doped carbon matrix (Ru-HMT-MP-7) is demonstrated, which is derived from HMT-based coordination polymers as superior pH-universal electrocatalysts. In the strategy, pyrolysis and phosphating processes are simultaneously proceeded that can produce the unique heterostructure containing three phases of RuO2 , RuP2, and Ru, at the same time the generated RuO2 -RuP2 /Ru can be highly dispersed on the self-assembly N, P co-doped carbon substrates. The resulting heterostructure Ru-HMT-MP-7 exhibits excellent activity superior to that of benchmark Pt/C with low overpotentials at 10 mA cm-2 (33 mV for 1.0 M KOH, 29 mV for 0.5 M H2 SO4 and 86 mV for 1.0 M PBS) and long-term electrocatalysis durability toward HER at various pH values. The rational construction strategy paves a novel avenue for obtaining superior pH-universal catalysts for electrochemical energy storage and conversion.

19.
Small ; 18(7): e2105970, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34889035

RESUMEN

Rechargeable zinc-ion batteries (ZIBs), which adopt mild aqueous electrolytes with high power density and safety, have received significant interest. As the most widely used cathode material for ZIBs, manganese-based oxide has poor rate performance owing to its low electronic conductivity and slow ion diffusion kinetics. In this study, using the synergistic regulation strategy of defect engineering and atomic composition tuning, a mesoporous Al0.35 Mn2.52 O4 with an ultrahigh surface area (up to 82 m2 g-1 ) is fabricated through Al substitution in the Mn3 O4 , followed by an Al-selective leaching process. During the entire process, numerous defects are obtained in the spinel structure by removing ≈30% of the Al cations. Al substitution can improve the material conductivity, while cation defects can weaken the electrostatic effect and promote ion diffusion ability. Therefore, the Al0.35 Mn2.52 O4 cathode of ZIBs exhibits a high reversible capacity of 302 mAh g-1 at a current density of 100 mA g-1 . Furthermore, the reversible capacity remains at 147 mAh g-1 after 1000 cycles at a current density of 1500 mA g-1 . This synergistic regulation of atomic composition tuning and defect engineering provides a new perspective for improving the performance of electrode materials in ZIBs.

20.
Nano Lett ; 21(13): 5522-5531, 2021 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-34133181

RESUMEN

Cell-membrane-coated nanoparticles have emerged as a promising antitumor therapeutic strategy. However, the immunologic mechanism remains elusive, and there are still crucial issues to be addressed including tumor-homing capacity, immune incompatibility, and immunogenicity. Here, we reported a tumor-associated macrophage membrane (TAMM) derived from the primary tumor with unique antigen-homing affinity capacity and immune compatibility. TAMM could deplete the CSF1 secreted by tumor cells in the tumor microenvironment (TME), blocking the interaction between TAM and cancer cells. Especially, after coating TAMM to upconversion nanoparticle with conjugated photosensitizer (NPR@TAMM), NPR@TAMM-mediated photodynamic immunotherapy switched the activation of macrophages from an immunosuppressive M2-like phenotype to a more inflammatory M1-like state, induced immunogenic cell death, and consequently enhanced the antitumor immunity efficiency via activation of antigen-presenting cells to stimulate the production of tumor-specific effector T cells in metastatic tumors. This TAM-membrane-based photodynamic immunotherapy approach offers a new strategy for personalized tumor therapy.


Asunto(s)
Inmunoterapia , Nanopartículas , Macrófagos , Fármacos Fotosensibilizantes/uso terapéutico , Microambiente Tumoral
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