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1.
Molecules ; 29(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38731419

RESUMO

It is a valid path to realize the zero discharge of coal chemical wastewater by using the fractional crystallization method to recycle the miscellaneous salt in high-salinity wastewater. In this study, the thermodynamics and nucleation kinetics of sodium chloride (NaCl) and sodium sulfate (Na2SO4) crystallization in coal chemical wastewater were systematically studied. Through analyses of solubility, metastable zone width, and induction period, it was found that the impurity dimethoxymethane would increase the solid-liquid interface energy and critical crystal size during the nucleation of Na2SO4. Ternary phase diagrams of the pseudo-ternary Na2SO4-NaCl-H2O systems in simulated wastewater were plotted in the temperature range of 303.15 to 333.15 K, indicating that a co-ionization effect existed between NaCl and Na2SO4, and NaCl had a strong salting out effect on Na2SO4. Finally, the nucleation rate and growth rate of Na2SO4 crystals under simulated wastewater conditions were determined by the intermittent dynamic method, and the crystallization kinetic models of Na2SO4 were established. The crystallization nucleation of Na2SO4 crystals was found to be secondary nucleation controlled by surface reactions. The basic theoretical research of crystallization in this study is expected to fundamentally promote the application of fractional crystallization to realize the resource utilization of high-salinity wastewater in the coal chemical industry.

2.
Adv Mater ; 36(24): e2309360, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38479025

RESUMO

The method of salt-assisted vapor-liquid-solid (VLS) growth is introduced to synthesize 1D nanostructures of trichalcogenide van der Waals (vdW) materials, exemplified by niobium trisulfide (NbS3). The method uses a unique catalyst consisting of an alloy of Au and an alkali metal halide (NaCl) to enable rapid and directional growth. High yields of two types of NbS3 1D nanostructures, nanowires and nanoribbons, each with sub-ten nanometer diameter, tens of micrometers length, and distinct 1D morphology and growth orientation are demonstrated. Strategies to control the location, size, and morphology of growth, and extend the growth method to synthesize other transition metal trichalcogenides, NbSe3 and TiS3, as nanowires are demonstrated. Finally, the role of the Au-NaCl alloy catalyst in guiding VLS synthesis is described and the growth mechanism based on the relationships measured between structure (growth orientation, morphology, and dimensions) and growth conditions (catalyst volume and growth time) is discussed. These results introduce opportunities to expand the library of emerging 1D vdW materials to make use of their unique properties through controlled growth at nanoscale dimensions.

3.
Nat Commun ; 15(1): 2247, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38472172

RESUMO

Epitaxial growth is a fundamental step required to create devices for the semiconductor industry, enabling different materials to be combined in layers with precise control of strain and defect structure. Patterning the growth substrate with a mask before performing epitaxial growth offers additional degrees of freedom to engineer the structure and hence function of the semiconductor device. Here, we demonstrate that conditions exist where such epitaxial lateral overgrowth can produce complex, three-dimensional structures that incorporate cavities of deterministic size. We grow germanium on silicon substrates patterned with a dielectric mask and show that fully-enclosed cavities can be created through an unexpected self-assembly process that is controlled by surface diffusion and surface energy minimization. The result is confined cavities enclosed by single crystalline Ge, with size and position tunable through the initial mask pattern. We present a model to account for the observed cavity symmetry, pinch-off and subsequent evolution, reflecting the dominant role of surface energy. Since dielectric mask patterning and epitaxial growth are compatible with conventional device processing steps, we suggest that this mechanism provides a strategy for developing electronic and photonic functionalities.

4.
Mol Oncol ; 17(10): 2200-2212, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37584407

RESUMO

ROS proto-oncogene 1, receptor tyrosine kinase (ROS1) rearrangements are a crucial therapeutic target in non-small cell lung cancer (NSCLC). However, there is limited comprehensive analysis of the molecular patterns of ROS1 fusions. This study aimed to address this gap by analysing 135 ROS1 fusions from 134 Chinese NSCLC patients using next-generation sequencing (NGS). The fusions were categorized into common and uncommon based on their incidence. Our study revealed, for the first time, a unique distribution preference of breakpoints within ROS1, with common fusions occurring in introns 31-33 and uncommon fusions occurring in introns 34 and 35. Additionally, we identified previously unknown breakpoints within intron 28 of ROS1. Furthermore, we identified a close association between the distribution patterns of fusion partners and breakpoints on ROS1, providing important insights into the molecular landscape of ROS1 fusions. We also confirmed the presence of inconsistent breakpoints in ROS1 fusions between DNA-based NGS and RNA-based NGS through rigorous validation methods. These inconsistencies were attributed to alternative splicing resulting in out-of-frame or exonic ROS1 fusions. These findings significantly contribute to our understanding of the molecular characteristics of ROS1 fusions, which have implications for panel design and the treatment of NSCLC patients with ROS1 rearrangements.

5.
Nano Lett ; 23(13): 5894-5901, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37368991

RESUMO

Oxidation of transition metal dichalcogenides (TMDs) occurs readily under a variety of conditions. Therefore, understanding the oxidation processes is necessary for successful TMD handling and device fabrication. Here, we investigate atomic-scale oxidation mechanisms of the most widely studied TMD, MoS2. We find that thermal oxidation results in α-phase crystalline MoO3 with sharp interfaces, voids, and crystallographic alignment with the underlying MoS2. Experiments with remote substrates prove that thermal oxidation proceeds via vapor-phase mass transport and redeposition, a challenge to forming thin, conformal films. Oxygen plasma accelerates the kinetics of oxidation relative to the kinetics of mass transport, forming smooth and conformal oxides. The resulting amorphous MoO3 can be grown with subnanometer to several-nanometer thickness, and we calibrate the oxidation rate for different instruments and process parameters. Our results provide quantitative guidance for managing both the atomic scale structure and thin-film morphology of oxides in the design and processing of TMD devices.

6.
Adv Sci (Weinh) ; 10(18): e2300426, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37088797

RESUMO

The ability to synthesize compositionally complex nanostructures rapidly is a key to high-throughput functional materials discovery. In addition to being time-consuming, a majority of conventional materials synthesis processes closely follow thermodynamics equilibria, which limit the discovery of new classes of metastable phases such as high entropy oxides (HEO). Herein, a photonic flash synthesis of HEO nanoparticles at timescales of milliseconds is demonstrated. By leveraging the abrupt heating and cooling cycles induced by a high-power-density xenon pulsed light, mixed transition metal salt precursors undergo rapid chemical transformations. Hence, nanoparticles form within milliseconds with a strong affinity to bind to the carbon substrate. Oxygen evolution reaction (OER) activity measurements of the synthesized nanoparticles demonstrate two orders of magnitude prolonged stability at high current densities, without noticeable decay in performance, compared to commercial IrO2 catalyst. This superior catalytic activity originates from the synergistic effect of different alloying elements mixed at a high entropic state. It is found that Cr addition influences surface activity the most by promoting higher oxidation states, favoring optimal interaction with OER intermediates. The proposed high-throughput method opens new pathways toward developing next-generation functional materials for various electronics, sensing, and environmental applications, in addition to renewable energy conversion.


Assuntos
Ligas , Carbono , Entropia , Termodinâmica , Óxidos , Oxigênio
7.
Comb Chem High Throughput Screen ; 26(14): 2517-2526, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36959128

RESUMO

BACKGROUND: Sini decoction (SND) is a widely used Traditional Chinese Medicine (TCM). The reports of SND application in colorectal cancer (CRC) is limited. OBJECTIVE: The objective of this study is to investigate the anti-tumor activity of SND in the treatmeant of CRC. METHODS: SND was analyzed using high-performance liquid chromatography. A CRC metastasis model was established using murine CT-26 cells. Whole-body fluorescence imaging was used to observe CRC liver metastasis. Liver morphology was determined using hematoxylin-eosin staining. Cytokine mRNA expression (interleukin-2 (IL-2), interleukin-10 (IL-10), interferon-gamma (IFN-γ), and tumor necrosis factor beta (TNF-ß)) were determined using real-time reverse transcription polymerase chain reaction. Spectral flow cytometry was used to detect mouse tumor immune subgroups. Databases were used to find potential target genes of SND. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes were used to identify potential signaling pathways of target genes. RESULTS: SND suppressed CRC liver metastasis and alleviated liver injury in vivo. After SND treatment, IL-2 and IFN-γ were upregulated, whereas IL-10 and TGF-ß were downregulated. Moreover, CD3+, CD8+T cells, natural killer T cells, and macrophages increased significantly after SND treatment, while CD4+CD25+T cells decreased significantly. Importantly, increasing the aconite concentration had a better anti-tumor effect. Fifty-50 compounds in SND were screened, and 611 potential target genes were identified. Functional analyses showed that the genes were associated with the PI3K-Akt signaling pathway, EGFR tyrosine kinase inhibitor resistance, and HIF-1 signaling pathway. CONCLUSION: SND exerts anti-tumor activity by inhibiting tumor progression and enhancing antitumor immunity in mice, suggesting its application to prevent and treat CRC.


Assuntos
Neoplasias do Colo , Neoplasias Hepáticas , Camundongos , Animais , Interleucina-2 , Interleucina-10 , Modelos Animais de Doenças , Fosfatidilinositol 3-Quinases , Neoplasias do Colo/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Imunidade
8.
Polymers (Basel) ; 15(3)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36772026

RESUMO

Epoxy and epoxide composites have a wide range of outdoor applications wherein they are affected by ageing. In this study, epoxy casting plates and epoxy-based composite rods for use in overhead conductors were prepared. A concurrent investigation concerning the ageing of epoxy resins and their carbon fibre composites was carried out via artificially accelerated experiments under hygrothermal and salt mist conditions. The moisture penetration along the depth, water absorption, appearance, hardness, density of the epoxy resins, and variation patterns of the impact strength and tensile strength of the epoxy-based composites were investigated. The ageing mechanisms were explored using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Both ageing modes had essentially similar influences on the properties of the resins and their composites; moreover, they did not significantly affect the chemical structure and microstructure of the epoxy resin, with the physical adsorption of water primarily observed during the ageing process. The moisture absorption behaviour of the epoxy obeyed Fick's law. Although the water penetration rate in the salt mist ageing mode was slightly higher than that in the hygrothermal ageing mode during the early ageing stage, it was essentially the same during the later stage. The final moisture absorption rate at saturation was approximately 1.1% under both modes. The flexural strengths and impact strengths of the composites in both ageing modes followed a similar trend. They decreased gradually with the ageing time and then stabilized at almost the same value. The flexural strength was reduced from 803 MPa to 760 MPa and the impact strength from 383 J/m2 to 310 J/m2, indicating a decrease of approximately 5.4% and 19%, respectively. The absorbed water during the ageing process caused micro-cracks at the interface between the fibres and resin, weakening the interfacial strength and reducing the mechanical properties of the composites.

9.
Nano Lett ; 22(24): 9958-9963, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36511687

RESUMO

Single-crystal nanowires are of broad interest for applications in nanotechnology. However, such wires are subject to both the Rayleigh-Plateau instability and an ovulation process that are expected to lead to their break up into particle arrays. Single crystal Ru nanowires were fabricated with axes lying along different crystallographic orientations. Wires bound by equilibrium facets along their length did not break up through either a Rayleigh-Plateau or ovulation process, while wires with other orientations broke up through a combination of both. Mechanistic insight is provided using a level-set simulation that accounts for strongly anisotropic surface energies, providing a framework for design of morphologically stable nanostructures.

10.
Front Oncol ; 12: 1021342, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387218

RESUMO

Background: The clinical significance of majority oncogenic novel fusions is still unknown due to scarcity. Reciprocal ROS1 translocation is a rare form of ROS1 fusion and has not yet been clearly analyzed. Case presentation: A 44-year-old Chinese woman with a large dimension in the left lobe of the lung was admitted to the hospital with IVB lung adenocarcinoma. It was discovered that intron 28 of ROS1 and intron 6 of CD74 produced a unique reciprocal ROS1 rearrangement. In addition, the dual CD74-ROS1 fusions were discovered using the RNA next-generation sequencing (NGS) findings. Although benefiting from crizotinib and lorlatinib sequential treatment, the overall prognosis of the patient was relatively poor, whose progression-free survival was 4 and 5 months for crizotinib treatment and lorlatinib treatment, respectively. Conclusion: In summary, a novel ROS1-CD74 fusion identified by DNA NGS was translated into dual CD74-ROS1 transcripts. Furthermore, this patient with non-small cell lung cancer benefited from consecutive tyrosine kinase inhibitor therapy. Our discovery broadened the range of targetable ROS1 fusions and underlined the importance of sequential DNA and RNA sequencing in identifying uncommon but beneficial fusions, which eventually bring benefits to the patients.

11.
World J Gastrointest Oncol ; 14(8): 1528-1539, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36160735

RESUMO

BACKGROUND: Approximately half of all new cases of gastric cancer (GC) and related deaths occur in China. More than 80% of patients with GC are diagnosed at an advanced stage, which results in poor prognosis. Although HER2-directed therapy and immune checkpoint inhibitors have been somewhat successful, new drugs are still needed for the treatment of GC. Notably, several gene fusion-targeted drugs have been approved by the United States Food and Drug Administration for solid tumors, including GC, such as larotrectinib for NTRK fusion-positive cancers and zenocutuzumab for NRG1 fusion-positive cancers. However, gene fusions involving targetable genes have not been well characterized in Chinese patients with GC. AIM: To identify the profile of fusions involving targetable genes in Chinese patients with GC using clinical specimens and determine the distribution of patients with gene fusion variants among the molecular subtypes of GC. METHODS: We retrospectively analyzed gene fusion events in tumor tissue samples from 954 Chinese patients with GC. Clinicopathological characteristics were obtained from their medical records. Genetic alterations, such as single nucleotide variants, indels, amplifications, and gene fusions, were identified using a targeted sequencing panel containing 825 genes. Fusions were validated by fluorescence in situ hybridization (FISH) using break-apart probes. The microsatellite instability (MSI) status was evaluated using MSIsensor from the targeted sequencing panel data. Tumor mutational burden (TMB) was calculated using the total number of nonsynonymous mutations divided by the total genomic targeted region. Chi-square analysis was used to determine the enrichment of gene fusions associated with the molecular subtypes of GC. RESULTS: We found that 1.68% (16/954) of patients harbored 20 fusion events involving targetable genes. RARA fusions (n = 5) were the most common, followed by FGFR2, BRAF, MET, FGFR3, RET, ALK, EGFR, NTRK2, and NRG1 fusions. Two of the RARA fusions, EML4-ALK (E6:E20) and EGFR-SEPTIN14 (E7:E10), have been identified in other tumors but not in GC. Surprisingly, 18 gene fusion events were previously not reported in any cancer types. Twelve of the eighteen novel gene fusions included complete exons encoding functional domains of targetable genes, such as the tyrosine kinase domain of receptor tyrosine kinases and the DNA- and ligand-binding domains of RARA. Consistent with the results of detection using the targeted sequencing fusion panel, the results of FISH (fluorescence in situ hybridization) confirmed the rearrangement of FGFR2 and BRAF in tumors from patients 04 and 09, respectively. Genetic analysis indicated that the fusion genes were significantly enriched in patients with ERBB2 amplification (P = 0.02); however, there were no significant differences between fusion-positive and fusion-negative patients in age, sex, MSI status, and TMB. CONCLUSION: We characterized the landscape of fusions involving targetable genes in a Chinese GC cohort and found that 1.68% of patients with GC harbor potential targetable gene fusions, which were enriched in patients with ERBB2 amplification. Gene fusion detection may provide a potential treatment strategy for patients with GC with disease progression following standard therapy.

12.
Environ Monit Assess ; 194(10): 780, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36098888

RESUMO

China is the largest producer and consumer of coal in the world. The extraction of coal is increasing intensively to meet the needs of the ever-increasing population and industries. However, coal mining has resulted in environmental changes, including deforestation, air, water, soil, and landform deterioration. This study investigates the impact of mining on the environment in Ruqigou coalfield by utilising in situ and remote sensing data. Field data collected include temperature, gas compositions, and water samples. Multi-temporal Landsat data of 1991, 2003, and 2019 were used in monitoring the impact of mining on different land covers, especially vegetation. A supervised classification was performed to assess the changes in land cover. In order to track the changes in vegetation, normalised difference vegetation index (NDVI) was employed. To study the changes in coal fire areas, thermal anomalies were extracted from the thermal infrared data using a dynamic thresholding technique. The results of in situ analyses show that water quality is unfit for domestic, industrial, and agricultural use. All the gas sampling sites emit noxious gases such as CO2, CO, NO2 and degrade the local air quality. The classified maps and vegetation indices show a significant decrease in vegetation. The thermal anomalies show an increase in fire areas over the years. Thus, it could be concluded that the conjunctive use of field-based measurements and remote sensing data can be a powerful tool for gaining a comprehensive understanding of the environmental impacts associated with large-scale mining.


Assuntos
Minas de Carvão , Incêndios , China , Carvão Mineral/análise , Monitoramento Ambiental/métodos , Tecnologia de Sensoriamento Remoto
13.
Sci Total Environ ; 853: 158437, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36057303

RESUMO

During the period of 2015-2018, Chinese government had made great efforts to mitigate air pollutants, such as air quality monitoring, energy structure adjustment, and pollutant emission reduction from industry, transportation and household sectors. With the special investment of 152 billion Chinese Yuan (CNY) in the Beijing-Tianjin-Hebei (BTH) and surrounding "2 + 26" regions, the annual local concentrations of PM2.5, PM10, SO2 and NO2 decreased from 77, 132, 38 and 46 µg/m3 to 60, 109, 20 and 43 µg/m3. It was estimated that the improvement in air quality avoided 27,021 (95 % CIs 12,548-39,738) premature deaths attributed to air pollution exposure based on an exposure-response function, including 45 %, 17 % and 15 % of cardiopulmonary, lung cancer and respiratory morality cases. Air pollution reduction was also effective in reducing work time loss, which reduced the total working time loss by 3.8 × 107 (95 % CIs 1.8 × 107-5.6 × 107) h, and the per capita working time loss by 0.28 (95 % CIs 0.13-0.41) h/capita by 2018. From the economic aspect, air pollution control actions in those regions saved 95.6 (95 % CIs 44.2-141) billion CNY economic loss by using the value of statistical life (VSL). The total benefit-cost ratio was 63.7 % (95 % CIs 29.4 %-93.7 %). The cost-effectiveness in Beijing and Tianjin were relatively low due to the regional contribution from other cities of the air pollution transmission channel. Despite the uncertainties, the results clearly show the significance of the environmental, health and economic benefits of actions in the BTH and surrounding "2 + 26" regions for combating air pollution.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Material Particulado/análise , Pequim , Dióxido de Nitrogênio , Poluição do Ar/análise , Poluentes Atmosféricos/análise , Cidades , China , Monitoramento Ambiental
14.
Front Oncol ; 12: 898954, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35847849

RESUMO

Background: Expanding the druggable novel anaplastic lymphoma kinase (ALK) fusions list is crucial to the precise treatment of patients with cancer with positive ALK fusions. The intergenic-ALK fusions accounted for a substantial proportion of ALK fusions. However, they were typically considered of limited clinical significance due to the obscure functional partners. In this case report, a patient carrying intergenic-ALK fusion presents an excellent outcome after taking the new second-generation tyrosine kinase inhibitor (TKI) candidate, WX-0593. Case Presentation: A 47-year-old Chinese female patient diagnosed with IVB lung adenocarcinoma was admitted to the hospital with large dimension lesions in the left lobe of the lung. After 1 week of first line chemotherapy, no response was found. A novel ALK rearrangement generated by a fusion of the intergenic region between SLC8A1 and PKDCC to the intron 19 of ALK was presented after next-generation sequencing and was further confirmed by Sanger's sequencing. High expression of ALK was revealed by immunohistochemistry. The patient was directed to engage in phase III clinical trial (NCT04632758) and received an orally active second-generation ALK inhibitor WX-0593. Over the course of 17 months, the partial response was obtained without significant side effects. Conclusion: In summary, a patient with non-small cell lung cancer harboring a novel intergenic-ALK fusion, whose intergenic breakpoint was located between SLC8A1 and PKDCC, benefited from a potent ALK TKI candidate WX-0593. This finding extended the scope of targetable ALK fusions. More importantly, it highlighted the advantages of next-generation sequencing in identifying rare but functional ALK fusions, which eventually benefit patients.

15.
Science ; 377(6605): 539-543, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35901152

RESUMO

Nanoscale ionic programmable resistors for analog deep learning are 1000 times smaller than biological cells, but it is not yet clear how much faster they can be relative to neurons and synapses. Scaling analyses of ionic transport and charge-transfer reaction rates point to operation in the nonlinear regime, where extreme electric fields are present within the solid electrolyte and its interfaces. In this work, we generated silicon-compatible nanoscale protonic programmable resistors with highly desirable characteristics under extreme electric fields. This operation regime enabled controlled shuttling and intercalation of protons in nanoseconds at room temperature in an energy-efficient manner. The devices showed symmetric, linear, and reversible modulation characteristics with many conductance states covering a 20× dynamic range. Thus, the space-time-energy performance of the all-solid-state artificial synapses can greatly exceed that of their biological counterparts.

16.
Nano Lett ; 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35852159

RESUMO

Understanding structure at the interface between two-dimensional (2D) materials and 3D metals is crucial for designing novel 2D/3D heterostructures and improving the performance of many 2D material devices. Here, we quantify and discuss the 2D/3D interface structure and the 3D morphology in several materials systems. We first deposit faceted Au nanoislands on graphene and transition metal dichalcogenides, using measurements of the equilibrium island shape to determine values for the 2D/Au interface energy and examining the role of surface reconstructions, chemical identity, and defects on the grown structures. We then deposit the technologically relevant metals Ti and Nb under conditions where kinetic rather than thermodynamic factors govern growth. We describe a transition from dendritic to faceted islands as a function of growth temperature and discuss the factors determining island shape in these materials systems. Finally, we show that suspended 2D materials enable the fabrication of a novel type of 3D/2D/3D heterostructure and discuss the growth mechanism. We suggest that emerging nanodevices will utilize versatile fabrication of 2D/3D heterostructures with well-characterized interfaces and morphologies.

17.
J Neurotrauma ; 39(21-22): 1547-1560, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35658673

RESUMO

Traumatic brain injury (TBI) and obesity are two common conditions in modern society; both can impair neuronal integrity and neurological function. However, it is unclear whether the coexistence of both conditions will worsen outcomes. Therefore, in a rat model, we aimed to investigate whether the coexistence of TBI and a high-fat diet (HFD) has an additive effect, leading to more severe neurological impairments, and whether they are related to changes in brain protein markers of oxidative stress, inflammation, and synaptic plasticity. Sprague-Dawley rats (female, ∼250 g) were divided into HFD (43% fat) and diet (CD) (17% fat) groups for 6 weeks. Within each dietary group, half underwent a TBI by a weight-drop device, and the other half underwent sham surgery. Short-term memory and sensory function were measured at 24 h, 1 week, 3 weeks, and 6 weeks post-TBI. Brain tissues were harvested at 24 h and 6 weeks post-TBI, and markers of oxidative stress, apoptosis, inflammation, and synaptic plasticity were measured via immunostaining and Western blotting. In rats without TBI, HFD increased the pre-synaptic protein synaptophysin. In rats with TBI, HFD resulted in worsened sensory and memory function, an increase in activated macrophages, and a decrease in the endogenous antioxidant manganese superoxide dismutase (MnSOD). Our findings suggest that the additive effect of HFD and TBI worsens short term memory and sensation deficits, and may be driven by enhanced oxidative stress and inflammation.


Assuntos
Lesões Encefálicas Traumáticas , Animais , Ratos , Feminino , Ratos Sprague-Dawley , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/metabolismo , Encéfalo/metabolismo , Estresse Oxidativo , Inflamação/metabolismo , Biomarcadores/metabolismo
18.
Nature ; 604(7906): 479-485, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35444323

RESUMO

Protonic ceramic electrochemical cells hold promise for operation below 600 °C (refs. 1,2). Although the high proton conductivity of the bulk electrolyte has been demonstrated, it cannot be fully used in electrochemical full cells because of unknown causes3. Here we show that these problems arise from poor contacts between the low-temperature processed oxygen electrode-electrolyte interface. We demonstrate that a simple acid treatment can effectively rejuvenate the high-temperature annealed electrolyte surface, resulting in reactive bonding between the oxygen electrode and the electrolyte and improved electrochemical performance and stability. This enables exceptional protonic ceramic fuel-cell performance down to 350 °C, with peak power densities of 1.6 W cm-2 at 600 °C, 650 mW cm-2 at 450 °C and 300 mW cm-2 at 350 °C, as well as stable electrolysis operations with current densities above 3.9 A cm-2 at 1.4 V and 600 °C. Our work highlights the critical role of interfacial engineering in ceramic electrochemical devices and offers new understanding and practices for sustainable energy infrastructures.

19.
J Am Chem Soc ; 144(17): 7657-7666, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35471024

RESUMO

Nanoparticles decorated electrodes (NDEs) are useful in fuel cells, electrolyzers, water treatment, and chemical synthesis. Here, we show that by rapidly bringing a mixed ionic-electronic conductor outside its electrochemical stability window, one can achieve uniform dispersion of metallic nanoparticles inside its bulk and at the surface and improve its electrocatalytic performance when back under normal functional conditions. Surprisingly, this can happen under anodic as well as cathodic current/voltage shocks in an ABO3 perovskite oxide, La0.4Ca0.4Ti0.88Fe0.06Ni0.06O3-δ (LCTFN), across a wide range of H2/O2 gas environments at 800 °C. One possible mechanism for bulk Fe0/Ni0 precipitation under anodic shock condition is the incomplete oxygen oxidation (O2- → Oα-, 0 < α < 2), migration and escape of oxygen to interfaces, and "whiplash" transition-metal reduction due to low electronic conductivity. We show that both cathodic and anodic shocks can produce NDEs to enhance electrocatalytic performance, potentially improving the flexibility of this approach in practical devices.

20.
Cell Death Discov ; 8(1): 205, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35428780

RESUMO

Currently, surgical extraction is the main therapy for cholangiocarcinoma (CCA) patients, but it's highly susceptible to postsurgical complications and recurrence rate. Thus, we identified the suppressing roles of exosomal miR-15a-5p from umbilical cord mesenchymal stem cells (UCMSCs) in the EMT and metastasis of CCA. The microarray dataset GSE265566 was employed to determine the expression of CHEK1 in CCA tissues. The relationship of miR-15a-5p with CHEK1 was analyzed using bioinformatics tools and dual-luciferase reporter assay. The particle size of HUCMSCs-exo was detected by scanning electron microscopy and nanoparticle tracking analysis. The cellular and tumorous phenotypes were assessed through flow cytometry, CCK-8 assay, Transwell assay and the in vivo tumor xenograft experiments. CHEK1 was predicated to be markedly elevated in CCA. miR-15a-5p targeted CHEK1 and downregulated the expression of CHEK1. HUCMSCs-exo activated cell apoptosis but repressed the proliferative, invasive, and migratory potentials of CCA cells. After miR-15a-5p was silenced, HUCMSCs-exo presented an opposite effect in regulating CCA. Overexpression of miR-15a-5p promoted apoptosis but suppressed malignancy and tumorigenicity of CCA cells as well as EMT through downregulating CHEK1. Our data suggested that miR-15a-5p in HUCMSCs-exo suppresses EMT and metastasis of CCA through targeting downregulation of CHEK1.

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