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1.
Cell ; 180(5): 984-1001.e22, 2020 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-32109414

RESUMEN

Aging causes a functional decline in tissues throughout the body that may be delayed by caloric restriction (CR). However, the cellular profiles and signatures of aging, as well as those ameliorated by CR, remain unclear. Here, we built comprehensive single-cell and single-nucleus transcriptomic atlases across various rat tissues undergoing aging and CR. CR attenuated aging-related changes in cell type composition, gene expression, and core transcriptional regulatory networks. Immune cells were increased during aging, and CR favorably reversed the aging-disturbed immune ecosystem. Computational prediction revealed that the abnormal cell-cell communication patterns observed during aging, including the excessive proinflammatory ligand-receptor interplay, were reversed by CR. Our work provides multi-tissue single-cell transcriptional landscapes associated with aging and CR in a mammal, enhances our understanding of the robustness of CR as a geroprotective intervention, and uncovers how metabolic intervention can act upon the immune system to modify the process of aging.


Asunto(s)
Envejecimiento/genética , Restricción Calórica , Sistema Inmunológico/metabolismo , Transcriptoma/genética , Envejecimiento/metabolismo , Envejecimiento/patología , Animales , Reprogramación Celular/genética , Regulación de la Expresión Génica/genética , Redes Reguladoras de Genes/genética , Humanos , Ratas , Análisis de la Célula Individual
2.
Nature ; 624(7992): 611-620, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37907096

RESUMEN

Ageing is a critical factor in spinal-cord-associated disorders1, yet the ageing-specific mechanisms underlying this relationship remain poorly understood. Here, to address this knowledge gap, we combined single-nucleus RNA-sequencing analysis with behavioural and neurophysiological analysis in non-human primates (NHPs). We identified motor neuron senescence and neuroinflammation with microglial hyperactivation as intertwined hallmarks of spinal cord ageing. As an underlying mechanism, we identified a neurotoxic microglial state demarcated by elevated expression of CHIT1 (a secreted mammalian chitinase) specific to the aged spinal cords in NHP and human biopsies. In the aged spinal cord, CHIT1-positive microglia preferentially localize around motor neurons, and they have the ability to trigger senescence, partly by activating SMAD signalling. We further validated the driving role of secreted CHIT1 on MN senescence using multimodal experiments both in vivo, using the NHP spinal cord as a model, and in vitro, using a sophisticated system modelling the human motor-neuron-microenvironment interplay. Moreover, we demonstrated that ascorbic acid, a geroprotective compound, counteracted the pro-senescent effect of CHIT1 and mitigated motor neuron senescence in aged monkeys. Our findings provide the single-cell resolution cellular and molecular landscape of the aged primate spinal cord and identify a new biomarker and intervention target for spinal cord degeneration.


Asunto(s)
Senescencia Celular , Quitinasas , Microglía , Neuronas Motoras , Primates , Médula Espinal , Animales , Humanos , Biomarcadores/metabolismo , Quitinasas/metabolismo , Microglía/enzimología , Microglía/metabolismo , Microglía/patología , Neuronas Motoras/metabolismo , Enfermedades Neuroinflamatorias/metabolismo , Enfermedades Neuroinflamatorias/patología , Primates/metabolismo , Reproducibilidad de los Resultados , Análisis de Expresión Génica de una Sola Célula , Médula Espinal/metabolismo , Médula Espinal/patología
3.
Small ; 20(12): e2307011, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37946683

RESUMEN

It is crucial to rationally design and synthesize atomic-scale transition metal-doped carbon catalysts with high electrocatalytic activity to achieve a high-efficient oxygen reduction reaction (ORR). Herein, an electrocatalyst comprised of Fe-Fe dual atom pairs and N-doped concave carbon are reported (N-CC@Fe DA) that achieves ultrahigh electrocatalytic ORR activity. The catalyst is prepared by a gaseous doping approach, with zeolitic imidazolate framework-8 (ZIF-8) as the carbon framework precursor and cyclopentadienyliron dicarbonyl dimer as the Fe-Fe atom pair precursor. The catalyst exhibits high cathodic ORR catalytic performance in an alkaline Zn/air battery and proton exchange membrane fuel cell (PEMFC), yielding peak power densities of 241 mW cm-2 and 724 mW cm-2, respectively, compared to 127 mW cm-2 and 1.20 W cm-2 with conventional Pt/C catalysts as cathodes. The presence of Fe atom pairs coordinate with N atoms is revealed by X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS) analysis, and Density Functional Theory (DFT) calculation results show that the Fe-Fe pair structure is beneficial for adsorbing oxygen molecules, activating the O─O bond, and desorbing OH* intermediates formed during oxygen reduction, resulting in a more efficient oxygen reaction. The findings may provide a new pathway for preparing ultra-high-performance doped carbon catalysts with Fe-Fe atom pair structures.

4.
Small ; 20(22): e2306203, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38128031

RESUMEN

Semiconductor core/shell quantum dots (QDs) are considered promising building blocks to fabricate photoelectrochemical (PEC) cells for the direct conversion of solar energy into hydrogen (H2). However, the lattice mismatch between core and shell in such QDs results in undesirable defects and severe carrier recombination, limiting photo-induced carrier separation/transfer and solar-to-fuel conversion efficiency. Here, an interface engineering approach is explored to minimize the core-shell lattice mismatch in CdS/CdSexS1-x (x = 0.09-1) core/shell QDs (g-CSG). As a proof-of-concept, PEC cells based on g-CSG QDs yield a remarkable photocurrent density of 13.1 mA cm-2 under AM 1.5 G one-sun illumination (100 mW cm-2), which is ≈54.1% and ≈33.7% higher compared to that in CdS/CdSe0.5S0.5 (g-CSA) and CdS/CdSe QDs (g-CS), respectively. Theoretical calculations and carrier dynamics confirm more efficient carrier separation and charge transfer rate in g-CSG QDs with respect to g-CSA and g-CS QDs. These results are attributed to the minimization of the core-shell lattice mismatch by the cascade gradient shell in g-CSG QDs, which modifies carrier confinement potential and reduces interfacial defects. This work provides fundamental insights into the interface engineering of core/shell QDs and may open up new avenues to boost the performance of PEC cells for H2 evolution and other QDs-based optoelectronic devices.

5.
Small ; 20(25): e2310491, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38189624

RESUMEN

Single-atom metal-doped M-N-C (M═Fe, Co, Mn, or Ni) catalysts exhibit excellent catalytic activity toward oxygen reduction reactions (ORR). However, their performance still has a large gap considering the demand for their practical applications. This study reports a high-performance dual single-atom doped carbon catalyst (HfCo-N-C), which is prepared by pyrolyzing Co and Hf co-doped ZIF-8 . Co and Hf are atomically dispersed in the carbon framework and coordinated with N to form Co-N4 and Hf-N4 active moieties. The synergetic effect between Co-N4 and Hf-N4 significantly enhance the catalytic activity and durability of the catalyst. In an acidic medium, the ORR half-wave potential (E1/2) of the catalyst is up to 0.82 V , which is much higher than that of the Co-N-C catalyst without Hf co-doping (0.80 V). The kinetic current density of the catalyst is up to 2.49 A cm-2 at 0.85 V , which is 1.74 times that of the Co-N-C catalyst without Hf co-doping. Moreover, the catalyst exhibits excellent cathodic performance in single proton exchange membrane fuel cells and Zn-air batteries. Furthermore, Hf co-doping can effectively suppress the formation of H2O2, resulting in significantly improved stability and durability.

6.
J Environ Manage ; 358: 120788, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38608571

RESUMEN

Livestock is one of major sources of greenhouse gas (GHG) emissions in China. Clarifying spatiotemporal characteristics of GHG emissions from livestock and exploring influencing factors can provide reference for grasping regional changes of GHG emission and formulate strategies of carbon reduction for livestock industry. However, existing literatures considered both spatial and temporal impacts and dynamic evolution trend of these factors seldomly. This paper used the life cycle assessment (LCA) method to estimate GHG emissions of livestock in 114 cities of the YRB from 2000 to 2021. On this basis, spatiotemporal heterogeneity of influencing factors was analyzed by using geographically and temporally weighted regression (GTWR) model. Finally, future evolution trend of GHG emissions from livestock was predicted by combining traditional and spatial Markov chain. Four main results were listed as follows. Firstly, GHG emission in the life cycle of livestock industry increased from 57.202 million tons (Mt) carbon dioxide equivalent (CO2e) in 2000 to 77.568 Mt CO2e in 2021. Secondly, structure of livestock industry, labor flow and mechanization were vital factors that led to increase of GHG emissions from livestock. Positive effects of labor flow and mechanization were increasing year by year, while negative effect of urbanization and positive effect of economic development were decreasing year by year. Markov chain analysis shown that probability of keeping high level of GHG emissions of livestock in the YRB unchanged were 96% (T = 1) and 90% (T = 5), and there also existed a Matthew effect. In addition, probability of level transfer of GHG emission in urban livestock was spatially dependent. Government should formulate strategies for livestock development and optimize low-carbon transformation of energy structure for livestock and poultry husbandry based on local conditions and key driving factors in the future. Meanwhile, boundaries of administrative divisions should be broken to promote reduction of GHG emissions in livestock comprehensively.


Asunto(s)
Contaminación del Aire , Ganado , Ríos , China , Animales , Análisis Espacio-Temporal , Contaminación del Aire/prevención & control , Contaminación del Aire/estadística & datos numéricos , Monitoreo del Ambiente , Crianza de Animales Domésticos/métodos , Crianza de Animales Domésticos/estadística & datos numéricos
7.
Angew Chem Int Ed Engl ; : e202410517, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38896017

RESUMEN

Electrochemical nitrogen oxide ions reduction reaction (NOx-RR) shows great opportunity for ammonia production under ambient conditions. Yet, performing NOx-RR in strong acidic conditions remains challenging due to the corrosion effect on the catalyst and competing hydrogen evolution reactions. Here, we demonstrate a stable La1.5Sr0.5Ni0.5Fe0.5O4 perovskite oxide for the NOx-RR at pH 0, achieving a Faradaic efficiency for ammonia of approaching 100% at a current density of 2 A cm-2 in a H-type cell. At industrially relevant current density, the NOx-RR system shows stable cell voltage and Faradaic efficiency for >350 h in membrane electrode assembly (MEA) at pH 0. By integrating the catalyst in a stacked MEA with a series connection, we have successfully obtained a record-breaking 2.578 g h-1 NH3 production rate at 20 A. This catalyst's unique acid-operability streamlines downstream ammonia utilization for direct ammonium salt production and upstream integration with NOx sources. Techno-economic and lifecycle assessments reveal substantial economic advantages for this ammonia production strategy, even when coupled with a plasma-based NOx production system, presenting a sustainable complement to the conventional Haber-Bosch process.

8.
J Neurosci ; 42(30): 5860-5869, 2022 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-35760530

RESUMEN

Thyroid hormone (TH) controls the timely differentiation of oligodendrocytes (OLs), and its deficiency can delay myelin development and cause mental retardation. Previous studies showed that the active TH T3 is converted from its prohormone T4 by the selenoprotein DIO2, whose mRNA is primarily expressed in astrocytes in the CNS. In the present study, we discovered that SECISBP2L is highly expressed in differentiating OLs and is required for DIO2 translation. Conditional knock-out (CKO) of Secisbp2l in OL lineage resulted in a decreased level of DIO2 and T3, accompanied by impaired OL differentiation, hypomyelination and motor deficits in both sexes of mice. Moreover, the defective differentiation of OLs in Secisbp2l mutants can be alleviated by T3 or its analog, but not the prohormone T4. The present study has provided strong evidence for the autonomous regulation of OL differentiation by its intrinsic T3 production mediated by the novel SECISBP2L-DIO2-T3 pathway during myelin development.SIGNIFICANCE STATEMENT Secisbp2l is specifically expressed in differentiating oligodendrocytes (OLs) and is essential for selenoprotein translation in OLs. Secisbp2l regulates Dio2 translation for active thyroid hormone (TH) T3 production in the CNS. Autonomous regulation of OLs differentiation via SECISBP2L-DIO2-T3 pathway.


Asunto(s)
Neurogénesis , Oligodendroglía , Selenoproteínas , Animales , Diferenciación Celular , Femenino , Yoduro Peroxidasa , Masculino , Ratones , Vaina de Mielina/metabolismo , Oligodendroglía/citología , Oligodendroglía/metabolismo , Selenoproteínas/biosíntesis , Selenoproteínas/genética , Hormonas Tiroideas , Yodotironina Deyodinasa Tipo II
9.
Small ; 19(49): e2303481, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37590378

RESUMEN

The development of bifunctional catalysts that facilitate both the hydrogen evolution reaction (HER) and hydrogen oxidation reaction (HOR) in alkaline environment is crucial for realizing unitized regenerative anion-exchange membrane fuel cells. In this study, a novel strategy to modulate the electron density of MoO3 through Ni doping (sample named Nix Mo1- x O3 ) is reported. Ni is incorporated to replace Mo atoms in MoO3 . Specifically, Nix Mo1- x O3 is combined with optimal adsorption energy, along with MoO2 /Mo2 N hybrid with high conductivity. The resulting Nix Mo1- x O3 supported on MoO2 /Mo2 N hybrid (sample named as Nix Mo1- x O3 -H) exhibits excellent alkaline HER activity, with an overpotential of only 16 mV at 10 mA cm-2 and a Tafel slope of 54 mV dec-1 . In addition, the Nix Mo1- x O3 -H demonstrates an ultrahigh HOR performance with a high exchange current density (3.852 mA cm-2 ). The catalyst's breakdown potential of 0.23 V indicates its ability to withstand higher voltages without breaking down. As evidenced by the results, this characteristic leads to improved stability. These results are higher than those of the other catalysts reported, which indicates that the electron density of MoO3 can be effectively modulated through Ni doping, leading to excellent HER and HOR performance.

10.
Nat Immunol ; 12(2): 178-85, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21217760

RESUMEN

Type 2 helper T cells (T(H)2) are critically involved in allergies and asthma. Here we demonstrate that extracellular matrix protein-1 (ECM1) is highly and selectively expressed in T(H)2 cells. ECM1 deficiency caused impaired T(H)2 responses and reduced allergic airway inflammation in vivo. Functional analysis demonstrated that although the T(H)2 polarization of ECM1-deficient cells was unimpaired, these cells had a defect in migration and were retained in peripheral lymphoid organs. This was associated with reduced expression of KLF2 and S1P(1). We also found that ECM1 could directly bind the interleukin-2 (IL-2) receptor to inhibit IL-2 signaling and activate S1P(1) expression. Our data identify a previously unknown function of ECM1 in regulating T(H)2 cell migration through control of KLF2 and S1P(1) expression.


Asunto(s)
Proteínas de la Matriz Extracelular/metabolismo , Hipersensibilidad/inmunología , Proteínas del Tejido Nervioso/metabolismo , Receptores Mensajeros de Linfocitos/metabolismo , Células Th2/metabolismo , Traslado Adoptivo , Animales , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Movimiento Celular/genética , Movimiento Celular/inmunología , Células Cultivadas , Modelos Animales de Enfermedad , Proteínas de la Matriz Extracelular/genética , Proteínas de la Matriz Extracelular/inmunología , Regulación de la Expresión Génica/inmunología , Humanos , Ganglios Linfáticos/patología , Ratones , Ratones Noqueados , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/inmunología , Receptores Mensajeros de Linfocitos/genética , Receptores Mensajeros de Linfocitos/inmunología , Transducción de Señal/inmunología , Células Th2/inmunología , Células Th2/patología , Transgenes/genética
11.
Nanotechnology ; 35(4)2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37848022

RESUMEN

In the dynamic landscape of the Internet of Things (IoT), where smart devices are reshaping our world, nanomaterials can play a pivotal role in ensuring the IoT's sustainability. These materials are poised to redefine the development of smart devices, not only enabling cost-effective fabrication but also unlocking novel functionalities. As the IoT is set to encompass an astounding number of interconnected devices, the demand for environmentally friendly nanomaterials takes center stage. ThisFocus Issuespotlights cutting-edge research that explores the intersection of nanomaterials and sustainability. The collection delves deep into this critical nexus, encompassing a wide range of topics, from fundamental properties to applications in devices (e.g. sensors, optoelectronic synapses, energy harvesters, memory components, energy storage devices, and batteries), aspects concerning circularity and green synthesis, and an array of materials comprising organic semiconductors, perovskites, quantum dots, nanocellulose, graphene, and two-dimensional semiconductors. Authors not only showcase advancements but also delve into the sustainability profile of these materials, fostering a responsible endeavour toward a green IoT future.

12.
Zhongguo Zhong Yao Za Zhi ; 48(1): 13-21, 2023 Jan.
Artículo en Zh | MEDLINE | ID: mdl-36725253

RESUMEN

Rheumatoid arthritis(RA) is a chronic degenerative joint disease characterized by inflammation. Due to the complex causes, no specific therapy is available. Non-steroidal anti-inflammatory agents and corticosteroids are often used(long-term, oral/injection) to interfere with related pathways for reducing inflammatory response and delaying the progression of RA, which, however, induce many side effects. Microneedle, an emerging transdermal drug delivery system, is painless and less invasive and improves drug permeability. Thus, it is widely used in the treatment of RA and is expected to be a new strategy in clinical treatment. This paper summarized the application of microneedles in the treatment of RA, providing a reference for the development of new microneedles and the expansion of its clinical application.


Asunto(s)
Artritis Reumatoide , Sistemas de Liberación de Medicamentos , Humanos , Administración Cutánea , Preparaciones Farmacéuticas , Antiinflamatorios no Esteroideos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Agujas
13.
Small ; 18(7): e2105803, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34894072

RESUMEN

Exploring highly active and stable bifunctional water-splitting electrocatalysts at ultra-high current densities is remarkably desirable. Herein, 3D nickel-iron phosphides nanosheets modified by MnOx nanoparticles are grown on nickel foam (MnOx /NiFeP/NF). Resulting from the electronic coupling effect enabled by interface modifications, the intrinsic activities of the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are improved. Meanwhile, 3D nanosheets provide abundant active sites for HER and OER, leading to accelerating the reaction kinetics. Besides, the shell-protection characteristic of MnOx improves the durability of MnOx /NiFeP/NF. Therefore, MnOx /NiFeP/NF shows exceptional bifunctional electrocatalytic activities toward HER (an overpotential of 255 mV at 500 mA cm-2 ), OER (overpotentials of 296 and 346 mV at 500 and 1000 mA cm-2 , respectively), and overall water splitting (cell voltages of 1.796 and 1.828 V at 500 and 1000 mA cm-2 , respectively). Furthermore, it owns remarkably outstanding stability for overall water splitting at ultra-high current densities (120 and 70 h at 500 and 1000 mA cm-2 , respectively), which outperforms almost all of the non-noble metal electrocatalysts. This work presents efficient strategies of interface modifications, 3D nanostructures, and shell protection to afford ultra-high current densities.

14.
Small ; 18(7): e2104934, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35018715

RESUMEN

In the past decade, atomically dispersed Fe active sites (coordinated with nitrogen) on carbon materials (FeNC) have emerged rapidly as promising single-atom catalysts (SACs) for the oxygen reduction reaction (ORR) to substitute precious group metal (PGM) catalysts, owing to their earth abundance and low cost. Nonetheless, the production of highly active FeNC SACs is largely restricted by material cost, low product yield and difficulty of microstructure design. Herein, the authors demonstrate a facile in-situ xerogel (ISG) assisted synthetic strategy, using cheap materials, to construct FeNC SACs (ISG FeNC). The porous silica xerogel, formed in-situ with the FeNC precursors, encourages the emergence of enormous micropores/mesopores and homogeneous confinement/protection to the precursors during pyrolysis, benefiting to the formation of abundant accessible active sites (27.6 × 1019 sites g-1 ). Correspondingly, the ISG FeNC exhibits excellent ORR activity with a half-wave potential (E1/2  = 0.91 V) in alkaline medium. The Zn-air battery assembled using the ISG FeNC SACs as the bifunctional catalyst of air cathode, demonstrates commendable performance with high peak power density of 249.1 mW cm-2 and superior long-term stability (660 cycles with 220 h). This work offers an economic and efficient way to fabricate PGM-free SACs for diverse applications.

15.
Small ; 18(14): e2107608, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35182010

RESUMEN

Titanium-based anode materials have achieved much progress with the wide studies in lithium-ion batteries. However, these known materials usually possess high discharge voltage platforms and limited energy densities. Herein, a titanium-based oxide of Na2 TiGeO5 with layered structure, two-dimensional lamellar frame and exposed highly active (001) facet, exhibiting good electrochemical performance in terms of high capacity (410 mAh g-1 with a current density of 50 mA g-1 ), excellent rate capability and cycling stability with no obvious capacity attenuation after 4000 cycles, is reported. The appropriate discharge voltage plateau at around 0.2 V endows the Na2 TiGeO5 anode material high security compared with graphite and high energy density compared with spinel Li4 Ti5 O12 . Combining the electrochemical tests and the density functional theory calculations, the Li+ storage mechanism of Na2 TiGeO5 is elucidated and the conversion reaction process is revealed. More importantly, this study provides a way to develop low-voltage and high-capacity titanium-based anode materials for efficient energy storage.

16.
Small ; 18(50): e2204828, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36310138

RESUMEN

Highly selective and sensitive H2 S sensors are in high demand in various fields closely related to human life. However, metal oxide semiconductors (MOSs) suffer from poor selectivity and single MOS@metal organic framework (MOF) core-shell nanocomposites are greatly limited due to the intrinsic low sensitivity of MOF shells. To simultaneously improve both selectivity and sensitivity, heterostructured α-Fe2 O3 @ZnO@ZIF-8 core-shell nanowires (NWs) are meticulously synthesized with the assistance of atomic layer deposition. The ZIF-8 shell with regular pores and special surface functional groups is attractive for excellent selectivity and the heterostructured α-Fe2 O3 @ZnO core with an additional electron depletion layer is promising with enhanced sensitivity compared to a single MOS core. As a result, the heterostructured α-Fe2 O3 @ZnO@ZIF-8 core-shell NWs achieve remarkable H2 S sensing performance with a high response (Rair /Rgas  = 32.2 to 10 ppm H2 S), superior selectivity, fast response/recovery speed (18.0/31.8 s), excellent long-term stability (at least over 3 months), and relatively low limit of detection (down to 200 ppb) at low operating temperature of 200 °C, far beyond α-Fe2 O3 @ZIF-8 or α-Fe2 O3 @ZnO core-shell NWs. Furthermore, a micro-electromechanical system-based H2 S gas sensor system with low power consumption is developed, holding great application potential in smart cities.

17.
Environ Sci Technol ; 56(1): 634-641, 2022 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-34902966

RESUMEN

Phosphonate is an important category of highly soluble organophosphorus in contaminated waters, and its oxidative transformation into phosphate is usually a prerequisite step to achieve the in-depth removal of the total phosphorus. Currently, selective oxidation of phosphonate into phosphate is urgently desired as conventional advanced oxidation processes suffer from severe matrix interferences. Herein, we employed 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) as a model phosphonate and demonstrated its efficient and selective oxidation by the Cu(II)/H2O2 process at alkaline pH. In the presence of trace Cu(II) (0.020 mM), 90.8% of HEDP (0.10 mM) was converted to phosphate by H2O2 in 30 min at pH 9.5, whereas negligible conversion was observed by UV/H2O2 or a Fenton reaction (pH = 3.0). The oxidation of HEDP by Cu(II)/H2O2 was insignificantly affected by natural organic matters (10.0 mg TOC/L) and various anions including chloride, sulfate, and nitrate (10.0 mM). The complexation of Cu(II) with HEDP coupling Cu(III) produced in situ enabled an intramolecular electron transfer process, which features high selective oxidation. Selective degradation of HEDP was further validated by adding stoichiometric H2O2 into an industrial effluent, where the existing Cu(II) could serve as the catalyst. This study also provides a successful case to trigger selective oxidation of trace pollutants of concern upon synergizing with the nature of the contaminated water.


Asunto(s)
Organofosfonatos , Contaminantes Químicos del Agua , Peróxido de Hidrógeno/química , Oxidación-Reducción , Fosfatos , Fósforo , Contaminantes Químicos del Agua/química
18.
Molecules ; 27(6)2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35335309

RESUMEN

We use computational materials methods to study the sequential appearance of zinc-based zeolitic imidazolate frameworks (ZIFs) generated in the mechanochemical conversion process. We consider nine ZIF topologies, namely RHO, ANA, QTZ, SOD, KAT, DIA, NEB, CAG and GIS, combined with the two ligands 2-methylimidazolate and 2-ethylimidazolate. Of the 18 combinations obtained, only six (three for each ligand) were actually observed during the mechanosynthesis process. Energy and porosity calculations based on density functional theory, in combination with the Ostwald rule of stages, were found to be insufficient to distinguish the experimentally observed ZIFs. We then show, using classical molecular dynamics, that only ZIFs withstanding quasi-hydrostatic pressure P ≥ 0.3 GPa without being destroyed were observed in the laboratory. This finding, along with the requirement that successive ZIFs be generated with decreasing porosity and/or energy, provides heuristic rules for predicting the sequences of mechanically generated ZIFs for the two ligands considered.


Asunto(s)
Zeolitas , Imidazoles/química , Simulación de Dinámica Molecular , Zeolitas/química , Zinc
19.
Molecules ; 27(24)2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36557778

RESUMEN

High-performance electrocatalysts are critical to support emerging electrochemical energy storage and conversion technologies. Graphite-derived materials, including fullerenes, carbon nanotubes, and graphene, have been recognized as promising electrocatalysts and electrocatalyst supports for the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), and carbon dioxide reduction reaction (CO2RR). Effective modification/functionalization of graphite-derived materials can promote higher electrocatalytic activity, stability, and durability. In this review, the mechanisms and evaluation parameters for the above-outlined electrochemical reactions are introduced first. Then, we emphasize the preparation methods for graphite-derived materials and modification strategies. We further highlight the importance of the structural changes of modified graphite-derived materials on electrocatalytic activity and stability. Finally, future directions and perspectives towards new and better graphite-derived materials are presented.

20.
Zhongguo Zhong Yao Za Zhi ; 47(18): 5008-5021, 2022 Sep.
Artículo en Zh | MEDLINE | ID: mdl-36164911

RESUMEN

The present study explored the main active ingredients and the underlying mechanism of Linderae Radix the treatment of gastric cancer by network pharmacology, molecular docking, and in vitro cell experiments. TCMSP, OMIM and GeneCards database were used to obtain the active ingredients of Linderae Radix to predict the related targets of both Linderae Radix and gastric cancer. After screening the common potential action targets, the STRING database was used to construct the PPI network for protein interaction of the two common targets. Enrichment analysis of GO and KEGG by DAVID database. Based on STRING and DAVID platform data, Cytoscape software was used to construct an "active ingredient-target" network and an "active ingredient-target-pathway" network. Molecular docking was performed using the AutoDock Vina to predict the binding of the active components to the key action targets, and finally the key targets and pathways were verified in vitro. According to the prediction results, there were 9 active components, 179 related targets of Radix Linderae, 107 common targets of Linderae Radix and gastric cancer, 693 biological processes, 57 cell compositions, and 129 molecular functions involved in the targets, and 161 signaling pathways involved in tumor antigen p53, hypoxia-indu-cible factor 1, etc. Molecular docking results showed that the core component, jimadone, had high binding activity with TP53. Finally, in an in vitro experiment, the screened radix linderae active ingredient gemmadone is used for preliminarily verifying the core targets and pathways of the human gastric cancer cell SGC-7901, The results showed that germacrone could significantly inhibit the proliferation of gastric cancer cells and induce the apoptosis of SGC-7901 by regulating the expression of p53, Bax, Bcl-2 and other key proteins. In summary, Radix Linderae can control the occurrence and development of gastric cancer through multi-components, multi-targets and multi-pathways, which will provide theoretical basis for further clinical discussion on the mechanism of Radix Linderae in treating gastric cancer.


Asunto(s)
Medicamentos Herbarios Chinos , Lindera , Medicina Tradicional China , Farmacología en Red , Neoplasias Gástricas , Antígenos de Neoplasias , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Humanos , Lindera/química , Simulación del Acoplamiento Molecular , Neoplasias Gástricas/tratamiento farmacológico , Proteína p53 Supresora de Tumor , Proteína X Asociada a bcl-2
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