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1.
EMBO Rep ; 25(3): 1361-1386, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38332150

RESUMO

Non-alcoholic fatty liver disease is a chronic liver abnormality that exhibits high variability and can lead to liver cancer in advanced stages. Hepatic ablation of SIRT6 results in fatty liver disease, yet the potential mechanism of SIRT6 deficiency, particularly in relation to downstream mediators for NAFLD, remains elusive. Here we identify Serpina12 as a key gene regulated by Sirt6 that plays a crucial function in energy homeostasis. Specifically, Sirt6 suppresses Serpina12 expression through histone deacetylation at its promoter region, after which the transcription factor, Cebpα, binds to and regulates its expression. Sirt6 deficiency results in an increased expression of Serpina12 in hepatocytes, which enhances insulin signaling and promotes lipid accumulation. Importantly, CRISPR-Cas9 mediated Serpina12 knockout in the liver ameliorated fatty liver disease caused by Sirt6 ablation. Finally, we demonstrate that Sirt6 functions as a tumor suppressor in the liver, and consequently, deletion of Sirt6 in the liver leads to not only the spontaneous development of tumors but also enhanced tumorigenesis in response to DEN treatment or under conditions of obesity.


Assuntos
Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Sirtuínas , Humanos , Sirtuínas/metabolismo , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatócitos/metabolismo , Neoplasias Hepáticas/metabolismo
2.
Hum Mol Genet ; 32(8): 1324-1333, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36434787

RESUMO

The objective of this study was to discuss the mechanism of artesunate (ART) in improving cartilage damage in osteoarthritis (OA) by regulating the expression levels of metastatic tumor antigen 1 (MTA1), lipoxin A4 (LXA4) and the downstream JAK2/STAT3 signaling pathway. The OA model in vitro was constructed by stimulating chondrocytes for 24 h with 10 ng/mL interleukin (IL)-1ß, and cell proliferation and apoptosis, expression levels of Aggrecan, MTA1, LXA4, MMP3, MMP13 and Collagen II, and inflammatory cytokines in the culture supernatants were examined. Histopathological changes, inflammatory response and chondrocyte apoptosis of the cartilage tissues of OA mice were performed. In vitro cell experiments, ART enhanced cell proliferation capacity, accompanied by decreased apoptosis rate, decreased expression of MMP-3 and MMP-13, elevated expression of Collagen II and Aggrecan, as well as reduced levels of IL-6 and TNF-α in the cell supernatant. ART also ameliorated IL-1ß-induced chondrocyte damage by upregulating MTA1. The LXA4 promoter region had two potential binding sites for MTA1. There was a positive correlation between MTA1 and LXA4. MTA1 enhanced the expression of LXA4 through transcription and blocked the activation of the JAK2/STAT3 signaling pathway. In vivo animal model experiments further showed that ART treatment alleviated cartilage tissue damage in OA model mice by upregulating MTA1. Our study demonstrates that ART improves the cartilage damage of OA by upregulating MTA1 expression and promoting the transcriptional activation of LXA4, and further blocking the JAK2/STAT3 signaling pathway.


Assuntos
Neoplasias , Osteoartrite , Camundongos , Animais , Artesunato/metabolismo , Ativação Transcricional , Agrecanas/metabolismo , Cartilagem/metabolismo , Condrócitos/metabolismo , Osteoartrite/patologia , Transdução de Sinais , Colágeno/metabolismo , Neoplasias/patologia , Interleucina-1beta/metabolismo
3.
Nano Lett ; 24(11): 3507-3514, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38445582

RESUMO

Layertronics, rooted in the layer Hall effect (LHE), is an emerging fundamental phenomenon in condensed matter physics and spintronics. So far, several theoretical and experimental proposals have been made to realize LHE, but all are based on antiferromagnetic systems. Here, using symmetry and tight-binding model analysis, we propose a general mechanism for engineering layertronics in a two-dimensional ferromagnetic multiferroic lattice. The physics is related to the band geometric properties and multiferroicity, which results in the coupling between Berry curvature and layer degree of freedom, thereby generating the LHE. Using first-principles calculations, we further demonstrate this mechanism in bilayer (BL) TcIrGe2S6. Due to the intrinsic inversion and time-reversal symmetry breakings, BL TcIrGe2S6 exhibits multiferroicity with large Berry curvatures at both the center and corners of the Brillouin zone. These Berry curvatures couple with the layer physics, forming the LHE in BL TcIrGe2S6. Our work opens a new direction for research on layertronics.

4.
J Am Chem Soc ; 146(11): 7771-7778, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38453653

RESUMO

Ammonia splitting to hydrogen is a decisive route for hydrogen economy but is seriously limited by the complex device and low efficiency. Here, we design and propose a new rechargeable Zn-NH3 battery based on temporally decoupled ammonia splitting to achieve efficient NH3-to-H2 conversion. In this system, ammonia is oxidized into nitrogen during cathodic charging (2NH3 + 6OH- → N2 + 6H2O + 6e-) with external electrical energy conversion and storage, while during cathodic discharging, water is reduced to hydrogen (2H2O + 2e- → H2 + 2OH-) with electrical energy generation. In this loop, continuous and efficient H2 production without separation and purification is achieved. With the help of the ammonia oxidation reaction (AOR) and hydrogen evolution reaction (HER) bifunctional catalyst of Mo2C/NiCu@C, a rechargeable Zn-NH3 battery is realized that exhibits a high NH3-to-H2 FE of 91.6% with outstanding durability for 900 cycles (300 h) at 20 mA/cm2, enabling efficient and continuous NH3-to-H2 conversion.

5.
Acc Chem Res ; 56(12): 1645-1655, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37282625

RESUMO

ConspectusIn the pursuit of maximizing the energy supply and sustainable energy development, high-energy-density energy storage systems beyond lithium-ion batteries are surging. The metal-catalysis battery, composed of a metal anode, electrolyte, and redox-coupled electrocatalyst cathode with gas, liquid, or solid as active reactants, is regarded as a promising energy storage and conversion system due to its dual functions of energy storage and chemical production. In this system, with the assistance of a redox-coupled catalyst, during discharging, the reduction potential energy of the metal anode is converted into chemicals along with electrical energy generation, while the external electrical energy is translated to the reduction potential energy of the metal anode and the oxidation potential energy of the reactants during charging. In this loop, the electrical energy and sometimes chemicals can be generated simultaneously. Although intensive effort has been devoted to the exploration of redox-coupled catalysts, the essence of the metal-catalysis battery, which is the prerequisite for further development and application, has been overlooked.In this Account, we present the journey of the metal-catalysis battery from development to essence and application and propose that the metal-catalysis battery system, which combines energy storage and electrocatalytic redox reactions with the characteristics of temporal decoupling and spatial coupling and an energy-conversion paradigm from electrical energy to chemicals via electrochemical energy storage, is achieved. First, inspired by the Zn-air/Li-air battery, we developed and realized Li-CO2/Zn-CO2 batteries and enriched the functions of the metal-catalysis battery from energy storage to chemical production. Based on OER/ORR and OER/CDRR catalysts, we have further explored OER/NO3-RR and HzOR/HER coupled catalysts and developed Zn-nitrate and Zn-hydrazine batteries. By extending the redox-coupled electrocatalyst systems from O, C species to N species and others, the metal-catalysis battery systems would develop from metal-Ox, Cx to metal-Nx and other batteries. Then, from Zn-CO2 and Zn-hydrazine batteries, we found that the overall reaction is decoupled into two separate reduction and oxidation reactions via the cathodic discharge and charge processes, and we further extracted the essence of the metal-catalysis battery, namely, the temporal-decouple and spatial-couple (TD-SC) mechanism, which is completely opposite to the conventional temporal couple and spatial decouple in electrochemical water splitting. Based on the TD-SC mechanism, we developed various applications of metal-catalysis batteries for the green and efficient synthesis of fine chemicals by modifying the metal anode and redox-coupled catalysts and electrolytes, including the Li-N2/H2 battery for NH3 synthesis and the organic Li-N2 battery for fine chemical synthesis. Finally, the main challenges and the possible opportunities for the metal-catalysis battery are discussed, including the rational design of highly efficient redox-coupled electrocatalysts and green electrochemical synthesis. The deep insight into the metal-catalysis battery will provide an alternative approach to energy storage and chemical production.

6.
Opt Express ; 32(2): 2867-2883, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297805

RESUMO

The van der Waals (vdWs) heterostructures, with vertical layer stacking structure of various two-dimensional (2D) materials, maintain the reliable photonic characteristics while compensating the shortcomings of the participating individual components. In this work, we combine the less-studied multilayer tin selenide (SnSe2) thin film with one of the traditional 2D materials, graphene, to fabricate the graphene-based vdWs optical switching element (Gr-SnSe2) with superior broadband nonlinear optical response. The transient absorption spectroscopy (TAS) measurement results verify that graphene acts as the recombination channel for the photogenerated carrier in the Gr-SnSe2 sample, and the fast recovery time can be reduced to hundreds of femtoseconds which is beneficial for the optical modulation process. The optical switching properties are characterized by the I-scan measurements, exhibiting a saturable energy intensity of 2.82 mJ·cm-2 (0.425 µJ·cm-2) and a modulation depth of 15.6% (22.5%) at the wavelength of 1030 nm (1980nm). Through integrating Gr-SnSe2 with a cladding waveguide, high-performance picosecond Q-switched operation in the near-infrared (NIR) and mid-infrared (MIR) spectral regions are both achieved. This work experimentally demonstrates the great potential of graphene-based vdWs heterostructures for applications in broadband ultrafast photonics.

7.
Nano Lett ; 23(11): 5367-5372, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37232533

RESUMO

The layer Hall effect (LHE) is of fundamental and practical importance in condensed-matter physics and material science; however, it was rarely observed and usually based on the paradigms of persistent electric field and sliding ferroelectricity. Here, a new mechanism of LHE is proposed by coupling layer physics with multiferroics using symmetry analysis and a low-energy k·p model. Due to time-reversal symmetry breaking and valley physics, the Bloch electrons on one valley will be subject to a large Berry curvature. This combined with inversion symmetry breaking gives rise to layer-polarized Berry curvature and can force the electrons to deflect in one direction of a given layer, thereby generating the LHE. We demonstrate that the resulting LHE is ferroelectrically controllable and reversible. Using first-principles calculations, this mechanism and predicted phenomena are verified in the multiferroic material of bilayer Co2CF2. Our finding opens a new direction for LHE and 2D materials research.

8.
J Hepatol ; 79(1): 109-125, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36907560

RESUMO

BACKGROUND & AIMS: Metastasis remains the major reason for the high mortality of patients with hepatocellular carcinoma (HCC). This study was designed to investigate the role of E-twenty-six-specific sequence variant 4 (ETV4) in promoting HCC metastasis and to explore a new combination therapy strategy for ETV4-mediated HCC metastasis. METHODS: PLC/PRF/5, MHCC97H, Hepa1-6, and H22 cells were used to establish orthotopic HCC models. Clodronate liposomes were used to clear macrophages in C57BL/6 mice. Gr-1 monoclonal antibody was used to clear myeloid-derived suppressor cells (MDSCs) in C57BL/6 mice. Flow cytometry and immunofluorescence were used to detect the changes of key immune cells in the tumour microenvironment. RESULTS: ETV4 expression was positively related to higher tumour-node-metastasis (TNM) stage, poor tumour differentiation, microvascular invasion, and poor prognosis in human HCC. Overexpression of ETV4 in HCC cells transactivated PD-L1 and CCL2 expression, which increased tumour-associated macrophage (TAM) and MDSC infiltration and inhibited CD8+ T-cell accumulation. Knockdown of CCL2 by lentivirus or CCR2 inhibitor CCX872 treatment impaired ETV4-induced TAM and MDSC infiltration and HCC metastasis. Furthermore, FGF19/FGFR4 and HGF/c-MET jointly upregulated ETV4 expression through the ERK1/2 pathway. Additionally, ETV4 upregulated FGFR4 expression, and downregulation of FGFR4 decreased ETV4-enhanced HCC metastasis, which created a FGF19-ETV4-FGFR4 positive feedback loop. Finally, anti-PD-L1 combined with FGFR4 inhibitor BLU-554 or MAPK inhibitor trametinib prominently inhibited FGF19-ETV4 signalling-induced HCC metastasis. CONCLUSIONS: ETV4 is a prognostic biomarker, and anti-PD-L1 combined with FGFR4 inhibitor BLU-554 or MAPK inhibitor trametinib may be effective strategies to inhibit HCC metastasis. IMPACT AND IMPLICATIONS: Here, we reported that ETV4 increased PD-L1 and chemokine CCL2 expression in HCC cells, which resulted in TAM and MDSC accumulation and CD8+ T-cell inhibition to facilitate HCC metastasis. More importantly, we found that anti-PD-L1 combined with FGFR4 inhibitor BLU-554 or MAPK inhibitor trametinib markedly inhibited FGF19-ETV4 signalling-mediated HCC metastasis. This preclinical study will provide a theoretical basis for the development of new combination immunotherapy strategies for patients with HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Camundongos , Animais , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Camundongos Endogâmicos C57BL , Transdução de Sinais , Macrófagos/metabolismo , Linhagem Celular Tumoral , Microambiente Tumoral , Proteínas Proto-Oncogênicas c-ets/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Quimiocina CCL2 , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/metabolismo
9.
Angew Chem Int Ed Engl ; 62(30): e202306506, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37254704

RESUMO

Solar-to-electrochemical energy storage in solar batteries is an important solar utilization technology comparable to solar-to-electricity (solar cells) and solar-to-fuel (photocatalytic cells) conversion. Unlike the indirect approach of integrated solar flow batteries combining photoelectrodes with redox-electrodes, coupled solar batteries enable direct solar energy storage, but are hampered by low efficiency due to rapid charge recombination of materials and misaligned energy levels between electrodes. Herein, we propose a design for a coupled solar battery that intercouples two photo-coupled ion transfer (PCIT) reactions through electron-ion transfer upon co-photo-pumping of photoelectrochemical storage cathode and anode. We used a representative covalent organic framework (COF) to achieve efficient charge separation and directional charge transfer between two band-matched photoelectrochemical storage electrodes, with a photovoltage sufficient for COF dual-redox reactions. By pumping these electrodes, the coupled solar battery stores solar energy via two synergistic PCIT reactions of electron-proton-relayed COF oxidation and reduction, and the stored solar energy is released as electrochemical energy during COF regeneration in discharge while interlocking the loops. A breakthrough in efficiency (6.9 %) was achieved, adaptive to a large-area (56 cm2 ) tandem device. The presented photo-intercoupled electron-ion transfer (PIEIT) mechanism provides expandable paths toward practical solar-to-electrochemical energy storage.

10.
Cancer Sci ; 113(10): 3347-3361, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35848884

RESUMO

RNA-binding protein (RBP) dysregulation is functionally linked to several human diseases, including neurological disorders, cardiovascular disease, and cancer. Heterogeneous nuclear ribonucleoproteins (hnRNPs) are a diverse family of RBPs involved in nucleic acid metabolism. A growing body of studies has shown that the dysregulated hnRNPs play important roles in tumorigenesis. Here, we found that heterogeneous nuclear ribonucleoprotein C (C1/C2) (HNRNPC) had good performance in distinguishing between hepatocellular carcinoma (HCC) and normal liver tissues through bioinformatics analysis. Further investigation revealed that HNRNPC was significantly correlated with multiple malignant characteristics of HCC, including tumor size, microvascular invasion, tumor differentiation, and TNM stage. Patients with HCC with positive HNRNPC expression exhibited decreased overall survival and increased recurrence rate. HNRNPC downregulation inhibited HCC invasion and metastasis. The decreased expression of hypoxia inducible factor 1 subunit alpha (HIF1A) was identified as the molecular mechanism underlying HNRNPC downregulation-inhibited HCC metastasis by RNA sequencing. Mechanistically, HNRNPC downregulation decreased HIF1A expression by destabilizing HIF1A mRNA. HIF1A overexpression rescued the decrease in invasiveness and metastasis of HCC induced by HNRNPC downregulation. Additionally, interleukin (IL)-6/STAT3 signaling upregulated HNRNPC expression in HCC cells, and knockdown of HNRNPC significantly inhibited IL-6/STAT3-enhanced HCC metastasis. Furthermore, anti-IL-6 antibody siltuximab significantly inhibited IL-6-mediated HCC metastasis. In summary, our research revealed the clinical value, functional role, and molecular mechanism of HNRNPC in HCC and showed the potential of HNRNPC as a biomarker for diagnosis, prognosis, and further therapeutic targets for HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Ribonucleoproteínas Nucleares Heterogêneas Grupo C/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo C/metabolismo , Humanos , Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Interleucina-6/metabolismo , Neoplasias Hepáticas/patologia , Metástase Neoplásica , RNA Mensageiro , Proteínas de Ligação a RNA/genética , Fator de Transcrição STAT3/metabolismo
11.
Int J Mol Sci ; 23(8)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35457058

RESUMO

Carbon nanotubes (CNTs) are carbon allotropes consisting of one, two, or more concentric rolled graphene layers. These can intrinsically regulate immunity by activating the innate immune system. Mannose receptors (MR), a subgroup of the C-type lectin superfamily, are abundantly expressed on macrophages and dendritic cells. These play a crucial role in identifying pathogens, presenting antigens, and maintaining internal environmental stability. Utilizing the specific recognition between mannose and antigen-presenting cells (APC) surface mannose receptors, the antigen-carrying capacity of mannose-modified CNTs can be improved. Accordingly, here, we synthesized the mannose-modified carbon nanotubes (M-MWCNT) and evaluated them as an antigen delivery system through a series of in vitro and in vivo experiments. In vitro, M-MWCNT carrying large amounts of OVA were rapidly phagocytized by macrophages and promoted macrophage proliferation to facilitate cytokines (IL-1ß, IL-6) secretion. In vivo, in mice, M-MWCNT induced the maturation of dendritic cells and increased the levels of antigen-specific antibodies (IgG, IgG1, IgG2a, IgG2b), and cytokines (IFN-γ, IL-6). Taken together, M-MWCNT could induce both humoral and cellular immune responses and thereby can be utilized as an efficient antigen-targeted delivery system.


Assuntos
Nanotubos de Carbono , Animais , Antígenos , Citocinas , Imunidade Celular , Imunoglobulina G , Interleucina-6 , Manose , Receptor de Manose , Camundongos
12.
J Sci Food Agric ; 102(14): 6757-6770, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35638143

RESUMO

BACKGROUND: To improve the adjuvant activity of polysaccharides from Eucommia ulmoides leaves (PsEUL) in inducing an effective immune response against ovalbumin (OVA), PsEUL were conjugated to OVA using the N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC) method. The synthesized PsEUL-OVA was encapsulated using phytantriol and F127 to produce PsEUL-OVA cubosomes (Cubs), a novel delivery system. The physicochemical properties and immune modulation effects of this novel delivery system were explored. RESULTS: In vitro, PsEUL-OVA/Cubs carrying large amounts of OVA were rapidly phagocytized by macrophages and upregulated macrophage proliferation, thereby stimulating cytokine production (interleukin (IL)-6 and IL-4). In vivo, PsEUL-OVA/Cubs increased the titer of OVA-specific antibodies (immunoglobulin (Ig)G, IgG2b, IgG2a and IgG1) and cytokine levels (IL-2, IL-6, IL-4 and interferon-γ). In addition, the cubosomes promoted the differentiation of CD8+ and CD4+ T cells in the spleen and the maturation of dendritic cells (DCs). These results indicated that PsEUL-OVA/Cubs stimulated both cellular and humoral immune responses by enhancing the phagocytic activity of DCs and macrophages and increasing the antigen presentation efficiency. CONCLUSION: Collectively, the findings demonstrate that PsEUL-antigen/Cubs can be a useful delivery vehicle with immune response-promoting effects. Therefore, this study lays the foundation for the development of novel adjuvant-antigen delivery systems with potential applications in vaccine design. © 2022 Society of Chemical Industry.


Assuntos
Eucommiaceae , Vacinas , Adjuvantes Imunológicos/farmacologia , Antígenos , Citocinas , Imunidade Humoral , Imunoglobulina G , Interferon gama , Interleucina-2 , Interleucina-4 , Interleucina-6 , Ovalbumina/química , Folhas de Planta , Polissacarídeos/química
13.
Angew Chem Int Ed Engl ; 61(17): e202115908, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35156276

RESUMO

Stable and soluble redox-active nitroxyl radicals are highly desired for high-capacity and long-life aqueous zinc hybrid flow batteries (AZHFBs). Here we report a "π-π" conjugated imidazolium and "p-π" conjugated acetylamino co-functionalized 2,2,6,6-tetramethylpiperidine-N-oxyl (MIAcNH-TEMPO) as stable catholyte for AZHFBs. The incorporation of double-conjugate substituents could delocalize the electron density of the N-O head and thus remarkably stabilize the radical and oxoammonium forms of TEMPO, avoiding the side reaction of ring-opening. Consequently, the applied MIAcNH-TEMPO/Zn AZHFB demonstrates the hardly time-dependent stability with a constant capacity retention of 99.95 % per day over 16.7 days at a high concentration catholyte of 1.5 M and high current density of 50 mA cm-2 . This proposed molecular engineering strategy based on electron density regulation of redox-active structures displays an attractive efficacy and thus represents a remarkable advance in high-performance AZHFBs.

14.
Angew Chem Int Ed Engl ; 61(50): e202214816, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36280902

RESUMO

Photoresponsive batteries promise flexible and low-cost solar-to-electrochemical energy storage (SES), but suffer from a limited SES efficiency due to rapid charge recombination and sluggish redox. Here, we present a porous-shell/core hybrid of covalent organic framework@carbon nanotube. This hybrid ensures long-lived separated charges (τave =3.0 ns) by an electron transfer relay starting from the donor-acceptor molecules to the nanoscale heterojunction. These charges are further allowed to drive high-rate redox of -C=O/-C-O- and -C-N/-C=N+ with facile kinetics. Equipped with this photoelectrochemical cathode, a photoresponsive aqueous battery shows a 5-fold enhancement in SES efficiency (1.1 % at 1 sun) over their counterparts. It is unveiled that the electron relay favors the formation of electron-enriching -C-O- and hole-enriching -C=N+ groups responsible for photoelectrochemical Zn2+ and OTf- storage cascade; and further, the general photo coupled ions transfer (PCIT) process is proposed. This work presents an inspiring photoelectrochemical cathode design and theoretical insight for photoresponsive batteries.

15.
J Immunol ; 202(9): 2546-2557, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30867238

RESUMO

Reactive oxygen species (ROS) are not only toxic substances inducing oxidative stress but also play a role as a second messenger in signal transduction through various receptors. Previously, B cell activation was shown to involve prolonged ROS production induced by ligation of BCR. However, the mechanisms for ROS production and ROS-mediated activation in B cells are still poorly understood. In this study, we demonstrate that BCR ligation induces biphasic ROS production in both mouse spleen B cells and the mouse B cell line BAL17; transient and modest ROS production is followed by sustained and robust ROS production at 2-6 h after BCR ligation. ROS production in the late phase but not in the early phase augments activation of signaling pathways, such as the NF-κB and PI3K pathways, and is essential for B cell proliferation. ROS production in the late phase appears to be mediated by NADPH oxidases (NOXes) because prolonged ROS production is inhibited by various NOX inhibitors, including the specific inhibitor VAS2870. BCR ligation-induced ROS production is also inhibited by CRISPR/Cas9-mediated deletion of either the Cyba gene encoding p22phox, the regulator of NOX1-4 required for their activation, or NOX3, whereas ROS production is not affected by double deficiency of the DUOXA1 and DUOXA2 genes essential for the activation of the NOX isoforms DUOX1 and DUOX2. These results indicate that NOXes play a crucial role in sustained but not early BCR signaling and suggest an essential role of NOX-dependent sustained BCR signaling in B cell activation.


Assuntos
Linfócitos B/imunologia , Proliferação de Células , NADPH Oxidases/imunologia , Espécies Reativas de Oxigênio/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Transdução de Sinais/imunologia , Animais , Linfócitos B/citologia , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Camundongos , Camundongos Knockout , NADPH Oxidases/genética , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/imunologia , Proteínas Nucleares/genética , Proteínas Nucleares/imunologia , Receptores de Antígenos de Linfócitos B/genética , Transdução de Sinais/genética
16.
Small ; 16(33): e2002850, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32686314

RESUMO

Metallic phase (1T) MoS2 has been regarded as an appealing material for hydrogen evolution reaction. In this work, a novel interface-induced strategy is reported to achieve stable and high-percentage 1T MoS2 through highly active 1T-MoS2 /CoS2 hetero-nanostructure. Herein, a large number of heterointerfaces can be obtained by interlinked 1T-MoS2 and CoS2 nanosheets in situ grown from the molybdate cobalt oxide nanorod under moderate conditions. Owing to the strong interaction between MoS2 and CoS2 , high-percentage of metallic-phase (1T) MoS2 of 76.6% can be achieved, leading to high electroconductivity and abundant active sites compared to 2H MoS2 . Furthermore, the interlinked MoS2 and CoS2 nanosheets can effectively disperse the nanosheets so as to enlarge the exposed active surface area. The near zero free energy of hydrogen adsorption at the heterointerface can also be achieved, indicating the fast kinetics and excellent catalytic activity induced by heterojunction. Therefore, when applied in hydrogen evolution reaction (HER), 1T-MoS2 /CoS2 heterostructure delivers low overpotential of 71 and 26 mV at the current density of 10 mA cm-2 with low Tafel slops of 60 and 43 mV dec-1 , respectively in alkaline and acidic conditions.

17.
Small ; 16(6): e1906595, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31965732

RESUMO

Potassium-ion batteries have attracted increasing attention for next-generation energy storage systems due to their high energy density and abundance of potassium. However, the lack of suitable anode highly hampers its practical application due to the large ionic radius of K+ . Herein, a Se3 P4 @mesoporous carbon (Se3 P4 @C) composite is reported as a high-performance anode for potassium-ion batteries. The Se3 P4 @C composite is synthesized through an in situ combination reaction between red phosphorus and Se within a porous carbon matrix. In this way, the nano-sized Se3 P4 is well confined in the porous carbon and thus exhibits a close contact with the carbon matrix. This can significantly improve the conductivity and alleviate the volume change during the cycling process. As a result, the Se3 P4 @C exhibits a high reversible initial capacity of 1036.8 mAh g-1 at a current density of 50 mA g-1 as well as an excellent cycle performance with a capacity decay of 0.07% per cycle over 300 cycles under 1000 mA g-1 . In terms of high specific capacity and stable cycling performance, the Se3 P4 @C anode is a promising candidate for advanced potassium-ion batteries.

18.
J Neurol Neurosurg Psychiatry ; 91(1): 21-32, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31658959

RESUMO

OBJECTIVES: To systematically review the efficacy and safety of anti-inflammatory agents for patients with major depressive disorders. METHODS: We searched the literature to identify potentially relevant randomised controlled trials (RCTs) up to 1 January 2019. The primary outcome was efficacy, measured by mean changes in depression score from baseline to endpoint. Secondary outcomes included response and remission rates and quality of life (QoL). Safety was evaluated by incidence of classified adverse events. Heterogeneity was examined using the I2 and Q statistic. Pooled standard mean differences (SMDs) and risk ratios (RRs) were calculated. Subgroup meta-analyses were conducted based on type of treatment, type of anti-inflammatory agents, sex, sponsor type and quality of studies. RESULTS: Thirty RCTs with 1610 participants were included in the quantitative analysis. The overall analysis pooling from 26 of the RCTs suggested that anti-inflammatory agents reduced depressive symptoms (SMD -0.55, 95% CI -0.75 to -0.35, I2=71%) compared with placebo. Higher response (RR 1.52, 95% CI 1.30 to 1.79, I2=29%) and remission rates (RR 1.79, 95% CI 1.29 to 2.49, I2=41%) were seen in the group receiving anti-inflammatory agents than in those receiving placebo. Subgroup analysis showed a greater reduction in symptom severity in both the monotherapy and adjunctive treatment groups. Subgroup analysis of non-steroidal anti-inflammatory drugs, omega-3 fatty acids, statins and minocyclines, respectively, disclosed significant antidepressant effects for major depressive disorder (MDD). For women-only trials, no difference in changes of depression severity was found between groups. Subanalysis stratified by sponsor type and study quality led to the same outcomes in favour of anti-inflammatory agents in both subgroups. Changes of QoL showed no difference between the groups. Gastrointestinal events were the only significant differences between groups in the treatment periods. CONCLUSIONS: Results of this systematic review suggest that anti-inflammatory agents play an antidepressant role in patients with MDD and are reasonably safe.


Assuntos
Anti-Inflamatórios/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Anti-Inflamatórios não Esteroides/uso terapêutico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
19.
J Org Chem ; 85(6): 4500-4506, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32098469

RESUMO

A (diacetoxyiodo)benzene-mediated intramolecular cycloaddition of olefins to construct tricyclic morpholines is presented. A series of substituted tricyclic morpholines were obtained in one-step simple operation under mild conditions, and the NMR studies were employed to see the interaction of reactants. The studies on stereochemistry showed that transformation of Z-alkene was inhibited, which is interpreted by density functional theory calculations on Z- and E-transition state models, and only E-alkene resulted in an anticycloaddition product, which is testified by a single-crystal X-ray diffraction analysis.

20.
BMC Neurol ; 20(1): 57, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32061264

RESUMO

BACKGROUND: Migraine is one of the most common neurological disorders that leads to disabilities. However, the conventional drug therapy for migraine might be unsatisfactory at times. Therefore, this meta-analysis aimed to evaluate the efficacy and safety of calcitonin-gene-related peptide binding monoclonal antibody (CGRP mAb) for the preventive treatment of episodic migraine, and provide high-quality clinical evidence for migraine therapy. METHODS: A systematic electronic database search was conducted to identify the potentially relevant studies. Two independent authors performed data extraction and quality appraisal. Mean difference (MD) and risk ratio (RR) were pooled for continuous and dichotomous data, respectively. The significance levels, weighted effect sizes and homogeneity of variance were calculated. RESULTS: Eleven high-quality randomized control trials that collectively included 4402 patients were included in this meta-analysis. Compared to placebo group, CGRP mAb therapy resulted in a reduction of monthly migraine days [weighted mean difference (WMD) = - 1.44, 95% CI = (- 1.68,- 1.19)] and acute migraine-specific medication days [WMD = - 1.28, 95% CI = (- 1.66,- 0.90)], with an improvement in 50% responder rate [RR = 1.51, 95% CI = (1.37,1.66)]. In addition, the adverse events (AEs) and treatment withdrawal rates due to AEs were not significantly different between CGRP mAb and placebo groups. Similar efficacy and safety results were obtained for erenumab, fremanezumab, and galcanezumab in subgroup analysis. CONCLUSIONS: The current body of evidence reveals that CGRP mAb is an effective and safe preventive treatment for episodic migraine.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Peptídeo Relacionado com Gene de Calcitonina/imunologia , Transtornos de Enxaqueca/prevenção & controle , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados/administração & dosagem , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
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