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1.
Artigo em Inglês | MEDLINE | ID: mdl-32130853

RESUMO

In this work, the stability behaviors of the state-of-the-art Fe/N/C and Pt/C catalysts (as well as the activation time of the latter) were first systematically investigated, under different cathode catalyst loadings, in the membrane electrode assemblies (MEA) in PEM fuel cells. Based on that, two types of cathode electrodes with the combination of Fe/N/C and Pt/C catalysts were developed (type I: layered hybrid catalysts with Pt/C next to the membrane and type II: uniformly mixed catalysts). In this way, the shortcomings of the Fe/N/C catalyst (the fast decay) and the Pt/C catalyst (the long activation time) can be compensated at the same time. The hybrid catalysts also showed a very short activation time (a few hours vs over 10 h for Pt/C with the same Pt loading). Comparing the two types of hybrid catalysts, type I shows a much higher current density. The loadings of the Fe/N/C and Pt/C catalysts in the hybrid electrode were systematically studied, with optimal values of 1.0 mg cm-2 for Fe/N/C and 0.035 mgPt cm-2 for Pt/C. The Pt loading of this hybrid catalyst (type I) at the cathode only takes ca. 30% of the U.S. Department of Energy (DOE) target of Pt usage (0.100 mgPt cm-2), while its mass activity of Pt (in H2/O2 PEMFC) is 0.22 A mgPt-1 at 0.9iR-free V, reaching half of the DOE activity target (0.44 A mgPt-1), which is among the best performances reported so far. Via both half-cell and single-cell electrochemical evaluations together with other characterizations, the origin of the improved activity and stability is believed to be the synergistic effect between Pt/C and Fe/N/C catalysts to ORR. This work provides an effective strategy for engineering highly performing MEA for the industrialization of PEM fuel cells.

2.
Cell ; 180(5): 984-1001.e22, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32109414

RESUMO

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.

3.
Nat Commun ; 11(1): 643, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005850

RESUMO

Lithium metal is an ideal anode for lithium batteries due to its low electrochemical potential and high theoretical capacity. However, safety issues arising from lithium dendrite growth have significantly reduced the practical applicability of lithium metal batteries. Here, we report the addition of octaphenyl polyoxyethylene as an electrolyte additive to enable a stable complex layer on the surface of the lithium anode. This surface layer not only promotes uniform lithium deposition, but also facilitates the formation of a robust solid-electrolyte interface film comprising cross-linked polymer. As a result, lithium|lithium symmetric cells constructed using the octaphenyl polyoxyethylene additive exhibit excellent cycling stability over 400 cycles at 1 mA cm-2, and outstanding rate performance up to 4 mA cm-2. Full cells assembled with a LiFePO4 cathode exhibit high rate capability and impressive cyclability, with capacity decay of only 0.023% per cycle.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32057234

RESUMO

Highly active catalyst for the hydrogen oxidation/evolution reactions (HOR and HER) plays an essential role for the water-to-hydrogen reversible conversion. Currently, increasing attention has been concentrated on developing low-cost, high-activity, and long-life catalytic materials, especially for acid media due to the promise of proton exchange membrane (PEM)-based electrolyzers and polymer electrolyte fuel cells. Although non-precious-metal phosphide (NPMP) catalysts have been widely researched, their electrocatalytic activity toward HER is still not satisfactory compared to that of Pt catalysts. Herein, a series of precious-metal phosphides (PMPs) supported on graphene (rGO), including IrP2-rGO, Rh2P-rGO, RuP-rGO, and Pd3P-rGO, are prepared by a simple, facile, eco-friendly, and scalable approach. As an example, the resultant IrP2-rGO displays better HER electrocatalytic performance and longer durability than the benchmark materials of commercial Pt/C under acidic, neutral, and basic electrolytes. To attain a current density of 10 mA cm-2, IrP2-rGO shows overpotentials of 8, 51, and 13 mV in 0.5 M dilute sulfuric acid, 1.0 M phosphate-buffered saline (PBS), and 1.0 M potassium hydroxide solutions, respectively. Additionally, IrP2-rGO also exhibits exceptional HOR performance in the 0.1 M HClO4 medium. Therefore, this work offers a vital addition to the development of a number of PMPs with excellent activity toward HOR and HER.

6.
Mol Neurobiol ; 57(1): 96-104, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31832973

RESUMO

Gallic acid (3,4,5-trihydroxybenzoic acid, GA), a phenolic acid, is ubiquitous in almost all parts of the plant. In the present study, a neuroinflammatory rat model using intranigral infusion of lipopolysaccharides (LPS, 4 µg/µL) was employed to study the neuroprotective effect of GA which was orally administered daily. Compared with the vehicle-treated rats, systemic administration of GA (100 mg/kg) significantly attenuated LPS-induced increases in glial fibrillary acidic protein (a biomarker of activated astrocytes) and ED-1 (a biomarker of activated microglia), as well as inducible nitric oxide synthase (iNOS, a proinflammatory enzyme) and interleukin-1ß (a proinflammatory cytokine), in the LPS-infused substantia nigra (SN) of rat brain. At the same time, GA attenuated LPS-induced elevation in heme oxygenase-1 level (a redox-regulated protein) and α-synuclein aggregation (a hallmark of CNS neurodegeneration), suggesting that GA is capable of inhibiting LPS-induced oxidative stress and protein conjugation. Furthermore, GA prevented LPS-induced caspase 3 activation (a biomarker of programmed cell death) and LPS-induced increases in receptor-interacting protein kinase (RIPK)-1 and RIPK-3 levels (biomarkers of necroptosis), indicating that GA inhibited LPS-induced apoptosis and necroptosis in the nigrostriatal dopaminergic system of rat brain. Moreover, an in vitro study was employed to investigate the anti-inflammatory effect of GA on BV2 microglial cells which were subjected to LPS (1 µg/mL) treatment. Consistently, co-incubation of GA diminished LPS-induced increases in iNOS mRNA and iNOS protein expression in the treated BV-2 cells as well as NO production in the culture medium. The anti-oxidative activity of GA was evaluated using iron-induced lipid peroxidation of brain homogenates. After 3-h incubation at 37 °C, GA was more potent than glutathione and less potent than trolox in inhibiting iron-induced lipid peroxidation. Conclusively, the present study suggests that GA is anti-inflammatory via attenuating LPS-induced neuroinflammation, oxidative stress, and protein conjugation. Furthermore, GA prevented LPS-induced programmed cell deaths of nigrostriatal dopaminergic neurons of the rat brain, suggesting that GA may be neuroprotective by attenuating neuroinflammation in CNS neurodegenerative diseases.

7.
ACS Appl Mater Interfaces ; 11(45): 42744-42750, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31638769

RESUMO

The rapid development of both wearable and implantable biofuel cells has triggered more and more attention on the lactate biofuel cell. The novel lactate/oxygen biofuel cell (L/O-BFC) with the direct electron transfer (DET)-type lactate oxidase (LOx) anode and the platinum group metal (PGM)-free Fe-N-C cathode is designed and constructed in this paper. In such a reasonable design, the surface-controlled direct two-electron electrochemical reaction of the lactate oxidase was determined by cyclic voltammetry (CV) on the carbon nanotube (CNT) modified electrode with favorable high electrochemical active surface area and electronic conductivity. Additionally, the biosensor based on DET-type LOx modified electrode impressively presented linear response to lactate with different concentrations from 0.000 mM to 12.300 mM. In particular, the apparent Michealis-constant (KMapp) calculated as 0.140 mM clearly indicates that LOx on CNT has strong affinity to the substrate lactate. Meanwhile, 4e- transfer oxygen reduction reaction (ORR) was proven to take place on the Fe-N-C catalysts inthe 0.1 M PBS system, indicating the advantage by using the Fe-N-C catalysts at the cathode of L/O-BFC. Last but not least, the L/O-BFC with the direct electron transfer (DET)-type lactate oxidase(LOx) anode and the Fe-N-C cathode produced an superior open circuit potential (OCP) of 0.264 V and a maximum output power density (OPD) of 24.430 µW cm-2 in O2 saturated 95.020 mM lactate solution. The above results will not only bring about significant interest in developing a DET-type biofuel cell, but also offer guiding direction to explore novel catalyst materials for the biofuel cell. This work enriches the research content and may push developments of the implantable and wearable biofuel cell forward.

8.
Small ; 15(47): e1904180, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31596058

RESUMO

Ir-based binary and ternary alloys are effective catalysts for the electrochemical oxygen evolution reaction (OER) in acidic solutions. Nevertheless, decreasing the Ir content to less than 50 at% while maintaining or even enhancing the overall electrocatalytic activity and durability remains a grand challenge. Herein, by dealloying predesigned Al-based precursor alloys, it is possible to controllably incorporate Ir with another four metal elements into one single nanostructured phase with merely ≈20 at% Ir. The obtained nanoporous quinary alloys, i.e., nanoporous high-entropy alloys (np-HEAs) provide infinite possibilities for tuning alloy's electronic properties and maximizing catalytic activities owing to the endless element combinations. Particularly, a record-high OER activity is found for a quinary AlNiCoIrMo np-HEA. Forming HEAs also greatly enhances the structural and catalytic durability regardless of the alloy compositions. With the advantages of low Ir loading and high activity, these np-HEA catalysts are very promising and suitable for activity tailoring/maximization.

9.
Environ Sci Pollut Res Int ; 26(32): 33260-33268, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31520374

RESUMO

Waste printed circuit boards (WPCBs) are usually dismantled, crushed, and sorted to WPCB metal-enriched scraps, still containing an amount of non-metallic materials. This research used slurry electrolysis to refine these WPCB metal-enriched scraps and to examine if a standard ionic liquid, [MIm]HSO4, can replace H2SO4 in the system. The impact of the refinement process on metal migration and transformation is discussed in detail. The results demonstrated that metals in WPCB metal-enriched scraps could be successfully refined using slurry electrolysis, and [MIm]HSO4 can be used to replace H2SO4 in the system. When 80% of H2SO4 was replaced by [MIm]HSO4 (electrolyte of 200 mL, 30 g/L CuSO4·5H2O, 60 g/L NaCl, 130 g/L H2SO4, and 1.624 A for 4 h), the total metal recovery rate is 85%, and the purity, current efficiency, and particle size of cathode metal powder were 89%, 52%, and 3.77 µm, respectively. Moreover, the microstructure of the cathode metal powder was dendritic in the H2SO4-CuSO4-NaCl slurry electrolysis system, whereas at an 80% [MIm]HSO4 substitution rate slurry electrolysis system, the cathode metal powder was irregular and accumulated as small-sized spherical particles. Thus, replacing inorganic leaching solvents with ionic liquids may provide a potential choice for the resources in WPCB metal-enriched scraps.


Assuntos
Resíduo Eletrônico/análise , Líquidos Iônicos/química , Metais/análise , Cobre/química , Eletrólise , Eletrólitos , Íons , Tamanho da Partícula , Solventes
10.
Lupus Sci Med ; 6(1): e000339, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413853

RESUMO

Objective: To explore whether varicella zoster virus (VZV) infection could increase the risk of disease flares in patients with SLE. Methods: Patients who had VZV reactivations between January 2013 and April 2018 were included from the SLE database (n=1901) of Shanghai Ren Ji Hospital, South Campus. Matched patients with SLE were selected as background controls with a 3:1 ratio. Patients with SLE with symptomatic bacterial infections of the lower urinary tract (UTI) were identified as infection controls. Baseline period and index period were defined as 3 months before and after infection event, respectively. Control period was the following 3 months after the index period. Flare was defined by SELENA SLEDAI Flare Index. Kaplan-Meier analysis, Cox regression model and propensity score weighting were applied. Results: Patients with VZV infections (n=47), UTI controls (n=28) and matched SLE background controls (n=141) were included. 16 flares (34%) in the VZV group within the index period were observed, as opposed to only 7.1% in UTI controls and 9.9% in background controls. Kaplan-Meier curve revealed that patients with a VZV infection had a much lower flare-free survival within the index period compared with the controls (p=0.0003). Furthermore, after adjusting for relevant confounders including baseline disease activity and intensity of immunosuppressive therapy, Cox regression analysis and propensity score weighting confirmed that VZV infection within 3 months was an independent risk factor for SLE flares (HR 3.70 and HR 4.16, respectively). Conclusions: In patients with SLE, recent VZV infection within 3 months was associated with increased risk of disease flares.

12.
Waste Manag ; 95: 370-376, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31351623

RESUMO

As an indispensable part of printed circuit boards (PCBs), central processing unit (CPU) slots contain a significant amount of precious metals which makes economic sense to recycle these materials. Slurry electrolysis is an attractive approach for electronic waste (e-waste) recycling. In this study, the effect of electrolyte reuse on the recovery of metals (Primarily aluminum, nickel, copper, lead, silver, palladium, platinum and gold), from waste CPU slots by slurry electrolysis is discussed in detail. These results show that metal recovery rate, more than 95% for all 13 cycles, was not affected by slurry electrolyte reuse during metal recycling from waste CPU slots, though the reuse of slurry electrolyte greatly impacted the distribution of metals in the anode residues, electrolyte and cathode metal powders. However, slurry electrolysis recovered metals from waste CPU slots and the effect of electrolyte reuse on the recovery of metals from waste CPU slots is discussed for the first time in this study. This could benefit the recycling process since it could improve cathode metal powders recovery rates by approximately 2 times. The acid usage could be significantly reduced by electrolyte reuse when compared to fresh electrolyte. Therefore, electrolyte reuse is demonstrated and slurry electrolysis is a feasible and potentially economically friendly choice for industrial e-waste recycling.


Assuntos
Resíduo Eletrônico , Cobre , Eletrólise , Eletrólitos , Reciclagem
13.
Water Res ; 161: 78-88, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31181449

RESUMO

Phosphonate is an important phosphorous species in the effluent of wastewater treatment plant (WWTP), contributing to eutrophication and interfering with phosphate removal in WWTP. It is particularly difficult to determine phosphonates in samples of complex solution chemistry, resulting in very limited information on their presence in environmental matrices. Herein, we proposed a sensitive method based on liquid chromatography tandem mass spectrometry (LC-MS/MS) to determine six quantitatively most important phosphonates even at the ng/L level, i.e., 2-phosphonobutane-1,2,4-tricarboxylic acid, 1-hydroxyethane 1,1-diphosphonic acid, nitrilotris(methylene phosphonic acid), ethylenediamine tetra(methylene phosphonic acid), hexamethylenediamine tetra(methylene phosphonic acid) and diethylenetriamine penta(methylene phosphonic acid). Trimethylsilyldiazomethane (TMSCHN2) derivatization of the target phosphonates is pre-requisite since it could greatly increase the sensitivity up to 2-3 orders of magnitude over direct analysis of the virgin ones. The sample pretreatment methods (including ion exchange and solid phase extraction(SPE)), the derivatization procedures, and the LC-MS/MS conditions were systematically optimized. The limits of quantitation for the six phosphonates in the background of tap water ranged from 1.4 µg/L to 57 µg/L for direct analysis, and from 5.0 ng/L to 200 ng/L for SPE enabled pre-concentration analysis, respectively. The reliability of the proposed method was successfully validated by analysis of authentic water samples collected from one river and three WWTPs (0.088-7200 µg/L phosphonates) with satisfactory recoveries (72-126%). To the best of knowledge, this is the first report on quantification of phosphonates in environmental samples in China.


Assuntos
Organofosfonatos , Poluentes Químicos da Água , China , Cromatografia Líquida , Metilação , Reprodutibilidade dos Testes , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Águas Residuárias
14.
Ann Rheum Dis ; 78(8): 1090-1100, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31142473

RESUMO

OBJECTIVES: A population of atypical memory B cells (AtMs) are greatly expanded in patients with active lupus, but their generation and pathophysiological roles are poorly defined. The aim of this study was to comprehensively characterise lupus AtMs with a purpose to identify therapeutic clues to target this B cell population in lupus. METHODS: Peripheral B cell subsets were measured by flow cytometry. Sorting-purified B cell subsets were subject to RNA sequencing and functional studies. Plasma cytokines and secreted immunoglobulins were detected by Luminex or ELISA. In situ renal B cells were detected by multiplexed immunohistochemistry. RESULTS: CD24-CD20hi AtMs were strongly increased in two Chinese cohorts of patients with treatment-naïve lupus. Gene expression profile indicated that B cell signalling and activation, lipid/saccharide metabolism and endocytosis pathways were abnormally upregulated in lupus AtMs. In addition, the mammalian target of rapamycin complex 1 (mTORC1) pathway was remarkably activated in lupus AtMs, and blocking mTORC1 signalling by rapamycin abolished the generation of T-bet+ B cells and terminal differentiation of lupus AtMs. Furthermore, lupus AtMs displayed a dysfunctional phenotype, underwent accelerated apoptosis, poorly co-stimulated T cells and produced proinflammatory cytokines. Interestingly, lupus AtMs were in a paradoxically differentiated status with markers pro and against terminal differentiation and enriched with antinucleosome reactivity. Finally, AtMs were accumulated in the kidneys of patients with lupus nephritis and associated with disease severity. CONCLUSIONS: These findings demonstrated that mTORC1-overactivated lupus AtMs are abnormally differentiated with metabolic and functional dysregulations. Inhibiting mTORC1 signalling might be an attractive option to target AtMs and to improve therapeutic effectiveness in patients with lupus.

15.
ACS Appl Mater Interfaces ; 11(14): 13185-13193, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30892871

RESUMO

The photoelectric properties of multiferroic double-perovskite Bi2FeCrO6 (BFCO), such as above-band gap photovoltages, switchable photocurrents, and bulk photovoltaic effects, have recently been explored for potential applications in solar technology. Here, we report the fabrication of photoelectrodes based on n-type ferroelectric (FE) semiconductor BFCO heterojunctions coated with p-type transparent conducting oxides (TCOs) by pulsed laser deposition and their application for photoelectrochemical (PEC) water oxidation. The photocatalytic properties of the bare BFCO photoanodes can be improved by controlling the FE polarization state. However, the charge recombination as well as the limited charge transfer kinetics in the photoanode/electrolyte cause major energy loss and thus hinder the PEC performance. We show that this problem may be addressed by the deposition of an ultrathin p-type NiO layer on the photoanode to enhance the charge transport kinetics and reduce charge recombination at surface-trapped states for increased surface band bending. A fourfold enhancement of photocurrent density, up to 0.4 mA cm-2 (at +1.23 V vs RHE), a best performance of stability over 4 h, and a high incident photon-to-current efficiency (∼3.7%) were achieved under 1 sun illumination in such p-NiO/n-BFCO heterojunction photoanodes. These studies reveal the optimization of PEC performance by polarization switching of BFCO and the successful achievement of p-TCOs/n-FE heterojunction photoanodes that are able to sustain water oxidation that is stable for many hours.

16.
Glia ; 67(7): 1333-1343, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30889310

RESUMO

Neural progenitor cells (NPCs) are sequentially specified into neurons and glia during the development of central nervous system. WNT/ß-catenin signaling is known to regulate the balance between the proliferation and differentiation of NPCs during neurogenesis. However, the function of WNT/ß-catenin signaling during gliogenesis remains poorly defined. Here, we report that activation of WNT/ß-catenin signaling disrupts astrogliogenesis in the developing spinal cord. Conversely, inhibition of WNT/ß-catenin signaling leads to precocious astrogliogenesis. Further analysis reveals that activation of WNT/ß-catenin pathway results in a dramatic increase of neurogenin 2 (Ngn2) expression in transgenic mice, and knockdown of Ngn2 expression in neural precursor cells can reverse the inhibitory effect of WNT/ß-catenin on astrocytic differentiation. Moreover, Ngn2 can directly bind to the promoters of several astrocyte specific genes and suppress their expression independent of STATs activity. Together, our studies provide the first in vivo evidence that WNT/ß-catenin signaling inhibits early astrogliogenesis via an Ngn2-dependent transcriptional repression mechanism.


Assuntos
Astrócitos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Diferenciação Celular/fisiologia , Proteínas do Tecido Nervoso/biossíntese , Neurogênese/fisiologia , Via de Sinalização Wnt/fisiologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Feminino , Expressão Gênica , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/genética
17.
Sci Rep ; 9(1): 2957, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30814583

RESUMO

Both sporadic observations and modelling studies suggest that subthermocline eddies (SEs) exist east of the Philippines, where interhemispheric waters meet. However, effects of SEs on water mass mixing have never been observed. Here, using data from mooring and buoy deployed in the frontal region of the interhemispheric water masses, we show for the first time that the SEs act as an "underwater mixer" of intermediate waters from north and south Pacific oceans. The SEs have typical swirl speeds of 0.1~0.4 m s-1 between 200 and 800 m depth with a dominant period of ~90 days. Variation in intermediate water salinity also had a period of ~90 days, lagging eddy speed by ~8 days. Horizontal eddy diffusivity representative of eddy mixing rate was quantified using a mixing-length framework. Horizontal eddy diffusivity had both surface and subthermocline maxima. The vertically varying eddy diffusivity can be used to improve parameterization of eddy stirring in the tropical Pacific by coarse-resolution ocean climate models. The effect of the SEs on mixing of intermediate water masses seems not resolved by available eddy-resolving ocean models typically used for this region.

18.
Materials (Basel) ; 12(6)2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30871139

RESUMO

In this work, we investigated three types of graphene (i.e., home-made G, G V4, and G V20) with different size and morphology, as additives to a lithium iron phosphate (LFP) cathode for the lithium-ion battery. Both the LFP and the two types of graphene (G V4 and G V20) were sourced from industrial, large-volume manufacturers, enabling cathode production at low cost. The use of wrinkled and/or large pieces of a graphene matrix shows promising electrochemical performance when used as an additive to the LFP, which indicates that the features of large and curved graphene pieces enable construction of a more effective conducting network to realize the full potential of the active materials. Specifically, compared to pristine LFP, the LFP/G, LFP/G V20, and LFP/G V4 show up to a 9.2%, 6.9%, and 4.6% increase, respectively, in a capacity at 1 C. Furthermore, the LFP combined with graphene exhibits a better rate performance than tested with two different charge/discharge modes. Moreover, from the economic and electrochemical performance view point, we also demonstrated that 1% of graphene content is optimized no matter the capacity calculated, based on the LFP/graphene composite or pure LFP.

19.
ACS Appl Mater Interfaces ; 11(14): 13714-13723, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30888140

RESUMO

Our work proposed a facile strategy for selective fabrication of the precise metalized patterns onto polymer substrates through the laser direct structuring (LDS) technology using organocopper compounds. Copper oxalate (CuC2O4) and copper acetylacetonate [Cu(acac)2] which can be used as laser sensitizers were first introduced into an acrylonitrile-butadiene-styrene (ABS) matrix for preparing LDS materials. After the activation with 1064 nm pulsed near-infrared laser, the Cu0 (metal copper) was generated from CuC2O4 and Cu(acac)2 and then served as catalyst species for the electroless copper plating (ECP). A series of characterizations were conducted to investigate the morphology and analyze the surface chemistry of ABS/CuC2O4 and ABS/Cu(acac)2 composites. Specially, the X-ray photoelectron spectroscopy analysis indicated that 58.3% Cu2+ in ABS/CuC2O4 was reduced to Cu0, while this value was 63.9% for ABS/Cu(acac)2. After 30 min ECP, the conductivities of copper circuit on ABS/CuC2O4 and ABS/Cu(acac)2 composites were 1.22 × 107 and 1.58 × 107 Ω-1·m-1, respectively. Moreover, the decorated patterns and near-field communication circuit were demonstrated by this LDS technology. We believe that this study paves the way for developing organocopper-based LDS materials, which have the potential for industrial applications.

20.
Protein Cell ; 10(4): 249-271, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30778920

RESUMO

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary cerebrovascular disease caused by a NOTCH3 mutation. However, the underlying cellular and molecular mechanisms remain unidentified. Here, we generated non-integrative induced pluripotent stem cells (iPSCs) from fibroblasts of a CADASIL patient harboring a heterozygous NOTCH3 mutation (c.3226C>T, p.R1076C). Vascular smooth muscle cells (VSMCs) differentiated from CADASIL-specific iPSCs showed gene expression changes associated with disease phenotypes, including activation of the NOTCH and NF-κB signaling pathway, cytoskeleton disorganization, and excessive cell proliferation. In comparison, these abnormalities were not observed in vascular endothelial cells (VECs) derived from the patient's iPSCs. Importantly, the abnormal upregulation of NF-κB target genes in CADASIL VSMCs was diminished by a NOTCH pathway inhibitor, providing a potential therapeutic strategy for CADASIL. Overall, using this iPSC-based disease model, our study identified clues for studying the pathogenic mechanisms of CADASIL and developing treatment strategies for this disease.


Assuntos
CADASIL/metabolismo , Células Endoteliais/patologia , Células-Tronco Pluripotentes Induzidas , Modelos Biológicos , Músculo Liso Vascular , Receptor Notch3/genética , Animais , Células Cultivadas , Xenoenxertos , Heterozigoto , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Camundongos Endogâmicos NOD , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Mutação , NF-kappa B/metabolismo
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