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1.
Mol Immunol ; 167: 53-61, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38359646

RESUMO

The spike protein of SARS-CoV-2 as well as its receptor binding domain (RBD) has been demonstrated to be capable of activating the release of pro-inflammatory mediators in endothelial cells and immune cells such as monocytes. However, the effects of spike protein or its RBD on airway epithelial cells and mechanisms underlying these effects have not been adequately characterized. Here, we show that the RBD of spike protein alone can induce bronchial epithelial inflammation in a manner of ATP/P2Y2 dependence. Incubation of human bronchial epithelia with RBD induced IL-6 and IL-8 release, which could be inhibited by antibody. The incubation of RBD also up-regulated the expression of inflammatory indicators such as ho-1 and mkp-1. Furthermore, ATP secretion was observed after RBD treatment, P2Y2 receptor knock down by siRNA significantly suppressed the IL-6 and IL-8 release evoked by RBD. Additionally, S-RBD elevated the phosphorylation level of ERK1/2, and the effect that PD98059 can inhibit the pro-inflammatory cytokine release suggested the participation of ERK1/2. These novel findings provide new evidence of SARS-CoV-2 on airway inflammation and introduce purinergic signaling as promising treatment target.


Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Humanos , Glicoproteína da Espícula de Coronavírus/metabolismo , Sistema de Sinalização das MAP Quinases , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Células Endoteliais/metabolismo , SARS-CoV-2/metabolismo , COVID-19/metabolismo , Transdução de Sinais , Mucosa Respiratória/metabolismo , Inflamação/metabolismo , Trifosfato de Adenosina/farmacologia , Trifosfato de Adenosina/metabolismo , Ligação Proteica
2.
Front Oncol ; 13: 1231094, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023206

RESUMO

Introduction: This study aimed to elucidate the relationship between dynamic genomic mutation alteration and pseudoprogression (PsPD)/hyperprogressive disease (HPD) in immunotherapy-treated advanced non-small-cell lung cancer (NSCLC), to provide clinical evidence for identifying and distinguishing between PsPD and HPD. Method: Patients with advanced NSCLC who were treated with anti-PD1 were enrolled. Whole blood was collected at baseline and post image progression. Serum was separated and sequenced using 425-panel next-generation sequencing analysis (NGS). Results: NGS revealed that not only single gene mutations were associated with PsPD/HPD before treatment, dynamic monitoring of the whole-blood genome mutation spectrum also varied greatly. Mutational burden, allele frequency%, and relative circulating tumor DNA abundance indicated that the fold change after image progression was much higher in the HPD group. Discussion: The gene mutation profiles of PsPD and HPD not only differed before treatment, but higher genome mutation spectrum post image progression indicated true disease progression in patients with HPD. This suggests that dynamic whole-genome mutation profile monitoring as NGS can distinguish PsPD from HPD more effectively than single gene detection, providing a novel method for guiding clinical immune treatment.

3.
Nanomaterials (Basel) ; 13(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37836301

RESUMO

The effect of odd viscosity on the instability of liquid film along a wavy inclined bottom with linear temperature variation is investigated. By utilizing the long-wave approximation, the non-linear evolution equation of the free surface is derived. By applying the normal mode method, the linear instability of thin film flow is investigated. With the help of multi-scale analysis methods, the weakly non-linear instability of thin film flow is also investigated. The results reveal that the Marangoni effect caused by non-uniform temperature distribution promotes the instability of the liquid film, while the odd viscosity has a stabilizing effect. In addition, for a positive local inclination angle θ, an increase in bottom steepness ζ inhibits the instability of the liquid film flow. In contrast, with a negative local inclination angle θ, increased bottom steepness ζ promotes the instability of the liquid film flow. The results of the temporal linear instability analysis and the weakly non-linear instability analysis have been substantiated through numerical simulations of the non-linear evolution equations.

4.
Mol Immunol ; 160: 95-102, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37413911

RESUMO

Despite the wide usage of ß2-adrenoceptor agonists in asthma treatment, they do have side effects such as aggravating inflammation. We previously reported that isoprenaline induced Cl- secretion and IL-6 release via cAMP-dependent pathways in human bronchial epithelia, but the mechanisms underlying the inflammation-aggravation effects of ß2-adrenoceptor agonists remain pooly understood. In this study, we investigated formoterol, a more specific ß2-adrenoceptor agonist, -mediated signaling pathways involved in the production of IL-6 and IL-8 in 16HBE14o- human bronchial epithelia. The effects of formoterol were detected in the presence of PKA, exchange protein directly activated by cAMP (EPAC), cystic fibrosis transmembrane conductance regulator (CFTR), extracellular signal-regulated protein kinase (ERK)1/2 and Src inhibitors. The involvement of ß-arrestin2 was determined using siRNA knockdown. Our results indicate that formoterol can induce IL-6 and IL-8 secretion in concentration-dependent manner. The PKA-specific inhibitor, H89, partially inhibited IL-6 release, but not IL-8. Another intracellular cAMP receptor, EPAC, was not involved in either IL-6 or IL-8 release. PD98059 and U0126, two ERK1/2 inhibitors, blocked IL-8 while attenuated IL-6 secretion induced by formoterol. Furthermore, formoterol-induced IL-6 and IL-8 release was attenuated by Src inhibitors, namely dasatinib and PP1, and CFTRinh172, a CFTR inhibitor. In addition, knockdown of ß-arrestin2 by siRNA only suppressed IL-8 release when a high concentration of formoterol (1 µM) was used. Taken together, our results suggest that formoterol stimulates IL-6 and IL-8 release which involves PKA/Src/ERK1/2 and/or ß-arrestin2 signaling pathways.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística , Interleucina-8 , Humanos , Fumarato de Formoterol/farmacologia , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Interleucina-8/metabolismo , Interleucina-6/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Inflamação , RNA Interferente Pequeno , Receptores Adrenérgicos/metabolismo
5.
Mol Immunol ; 153: 94-105, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36459792

RESUMO

The massive release of pro-inflammatory cytokines is a crucial step in triggering the inflammatory cascade in sepsis. Exploring the key molecules regulating the expression and release of multiple cytokines has important value for revealing the mechanism of the cytokine storm in sepsis. This study aimed to investigate the role of multifunctional nuclear protein non-POU domain containing octamer-binding protein (NONO) in the sepsis cytokine storm and to elucidate the underlying mechanism. We found that NONO expression in tissues and cells of sepsis mice was significantly upregulated. Downregulation of NONO expression inhibited the mRNA expression of multiple cytokines, including IL-6, IL-1ß, MCP-1, MIP-1α, and MIP-1ß in inflammatory cells from mice and human leukemic monocyte-THP1 cells challenged with lipopolysaccharide (LPS), and significantly decreased the level of these cytokines and TNF-α in the supernatant of THP1 cells challenged by LPS. Nono knockout also reduced the levels of TNF-α, IL-6, MIP-1α, and MIP-1ß in serum, alleviated hepatocyte edema, and improved the survival rate of sepsis mice. Reduced NONO expression decreased the phospho-ERK1/2 level in inflammatory cells from sepsis mice or THP1 cells challenged by LPS. Phospho-ERK1/2 inhibitor decreased the mRNA expression and concentration of cytokines in the culture supernatant of LPS-induced THP1 cells, similar to the effect of NONO knockdown. After LPS challenge, the levels of phospho-ERK1/2 and NONO were increased, with obvious colocalization in the nucleus and vesicular-like organelles in macrophages. NONO knockdown decreased nuclear translocation of phospho-ERK1/2 in LPS-challenged THP1 cells. These results suggest that NONO is a potentially critical molecule involved in multiple cytokine production in sepsis. Upregulated NONO in sepsis may promote the expression and release of multiple cytokines to participate in a sepsis cytokine storm by promoting ERK1/2 phosphorylation.


Assuntos
Sistema de Sinalização das MAP Quinases , Sepse , Camundongos , Humanos , Animais , Fator de Necrose Tumoral alfa/farmacologia , Lipopolissacarídeos/farmacologia , Interleucina-6 , Quimiocina CCL3 , Quimiocina CCL4/farmacologia , Síndrome da Liberação de Citocina , Fatores de Transcrição , Transdução de Sinais , Citocinas/genética , RNA Mensageiro , Proteínas de Ligação a DNA , Proteínas de Ligação a RNA/genética
6.
Opt Express ; 30(14): 25111-25120, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-36237049

RESUMO

Surface emitting lasers are attractive light sources for silicon integrated photonic circuits. High speed direct operation is of great importance for these lasers in high capacity and low cost on-chip communication system. Here, we demonstrate a 1.3 µm surface emitting ridge-waveguide distributed feedback (DFB) laser with second order grating and λ/4 phase shift grating, which can achieve a 24 Gb/s operation over a wide temperature. The fabricated lasers can achieve low threshold current as 6.8 mA, and 12.5 mA at 20, and 70°C, respectively. Stable single mode operation has been observed with high side mode suppression ratio (SMSR) > 40 dB at all temperatures (20-70 °C). Meanwhile, the surface emitting optical power can reach 1.7 mW at high temperature as 70 °C. 3 dB bandwidth of small signal response is 21 GHz and 12 GHz at 20 °C and 70 °C respectively. The far-field divergence angle of surface emitting beam is 13.4°×20.2° of 10 µm length second order grating coupler. The proposed laser may have great advantages of single mode, high speed modulation and good temperature tolerance. In addition, compared with conventional DFB lasers, the surface emitting DFB laser has no additional manufacturing process, which is simple to fabricate and easy to integrate with silicon platform.

7.
Artigo em Inglês | MEDLINE | ID: mdl-36231388

RESUMO

Environmental pollution is an inevitable primary responsibility in the production and management of enterprises, and it is the most severe challenge to achieving green production and sustainable development. Environmental pollution liability insurance (EPLI) can transfer corporate pollution liability to insurance companies, which affects corporate performance to a certain extent. However, the influencing factors of enterprise performance are complex, and EPLI also involves multiple subjects, so the impact of EPLI on enterprise performance is also complex. At first, this paper analyzes the possible relationship between EPLI and corporate performance based on the existing literature; subsequently, based on the list of EPLI-insured companies in 2014 and 2015 published by China's environmental protection department as a sample, this paper uses a fixed-effects model to conduct an empirical analysis, and the mediating role of corporate social responsibility (CSR) was then examined; finally, heterogeneity analysis of the initial conclusions was conducted. The following conclusions are drawn: firstly, there is a significant negative correlation between EPLI and corporate performance. Secondly, CSR played a mediating role in the effect of EPLI on corporate performance; that is, EPLI inhibited the rise of corporate performance by affecting CSR. Thirdly, the impact of EPLI on corporate performance is heterogeneous in terms of equity nature, corporate pollution level and marketization degree. The results of this paper enrich the economic impact theory of EPLI and have specific practical value for enterprise management and policymakers in the background of the green economy.


Assuntos
Seguro de Responsabilidade Civil , Desenvolvimento Sustentável , China , Poluição Ambiental , Humanos , Organizações , Responsabilidade Social
8.
Environ Sci Pollut Res Int ; 29(54): 82156-82168, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35750912

RESUMO

Permeable reactive barrier (PRB) is one of the most promising in situ treatment methods for shallow groundwater pollution. However, optimal design of PRB is very difficult due to a lack of comprehensive understanding of various complex influencing factors of PRB remediation. In this study, eight of the main factors of PRB, including hydraulic gradient I, permeability coefficient KPRB of PRB material, PRB length L, PRB width W, PRB distance from pollution source Dist., the ratio of the maximum adsorption capacity to Langmuir constant of PRB material Qmax/KL, the discharge rate of pollution source DR, and recharge concentration RC were investigated, to carry out the sensitivity analysis of PRB removal efficiency. The simulation experiments for Morris analysis were designed, and pollutant removal efficiency was numerically simulated by coupling MODFLOW and MT3DMS under two scenarios of high and low permeability and dispersivity. For a typical low permeability with low dispersity medium, the sensitivity ranking of factors from high to low is DR, RC, I, W, L, Dist., Qmax/KL, and KPRB, and for a typical high permeability with a high dispersity medium, the sensitivity ranking of factors from high to low is I, W, DR, Qmax/KL, L, RC, Dist., and KPRB. When considering multiple factors in PRB design, the greater the KPRB, L, W, Qmax/KL is, the higher the removal efficiency is; the greater the RC, I is, the lower the removal efficiency is. The rest factors remain ambiguous enhancement to removal efficiency.


Assuntos
Poluentes Ambientais , Água Subterrânea , Poluentes Químicos da Água , Poluentes Ambientais/análise , Poluentes Químicos da Água/análise , Adsorção
9.
Opt Express ; 30(9): 15757-15765, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35473289

RESUMO

Uncooled direct modulation DFB laser offers high speed transmission rate over a wide temperature range with high reliability and low cost, making it a cost-effective light source choice for 5G fronthaul and data center applications. However, a significant 3dB bandwidth decrease can be observed in high temperature for conventional DFB lasers. We present an uncooled DFB laser operating up to 85°C with extended direct modulation bandwidth and high reliability based on a novel groove-in-trench ridge waveguide structure, where two narrow grooves penetrating the active layer are etched symmetrically in the two conventional trenches by deep wet etching, respectively. By optimizing the distance between the groove and the mesa stripe, we obtain a 3dB bandwidth of 15.3 GHz at 85°C, which is a 3.7 GHz improvement compared with the conventional ridge waveguide DFB laser. Transmissions of 25 Gb/s NRZ signal at 25°C and 85°C with clear eye openings have been demonstrated. It also achieves 25 Gb/s transmission over 10 km optical fiber with a low power penalty of 0.5 dB for a bit error rate of 10-12 at 85°C. In addition, the result of 2000-hour aging test shows that the proposed groove-in-trench structure DFB lasers have the same excellent reliability as the conventional ones.

10.
Am J Pathol ; 192(1): 104-111, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34756873

RESUMO

The proinflammatory cytokine tumor necrosis factor-α (TNF-α) augments intracellular Ca2+ signaling and contractile responses of airway smooth muscles, leading to airway hyperresponsiveness. However, the underlying mechanism has not been fully elucidated. This study aimed to investigate the cellular mechanism of the potentiated contraction of mouse tracheal smooth muscle induced by TNF-α. The results showed that TNF-α triggered facilitation of mouse tracheal smooth muscle contraction in an epithelium-independent manner. The TNF-α-induced hypercontractility could be suppressed by the protein kinase C inhibitor GF109203X, the tyrosine kinase inhibitor genistein, the Src inhibitor PP2, or the L-type voltage-dependent Ca2+ channel blocker nifedipine. Following TNF-α incubation, the α1C L-type Ca2+ channel (CaV1.2) was up-regulated in cultured primary mouse tracheal smooth muscle cells. Pronounced phosphotyrosine levels were observed in mouse tracheas. In conclusion, this study shows that TNF-α enhanced airway smooth muscle contraction via protein kinase C-Src-CaV1.2 pathways, which provides novel insights into the pathologic role of proinflammatory cytokines in mediating airway hyperresponsiveness.


Assuntos
Contração Muscular , Músculo Liso/fisiologia , Traqueia/fisiologia , Fator de Necrose Tumoral alfa/farmacologia , Animais , Canais de Cálcio Tipo L/metabolismo , Carbacol/farmacologia , Masculino , Camundongos , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Fosfotirosina/metabolismo , Proteína Quinase C/metabolismo , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/fisiologia , Transdução de Sinais/efeitos dos fármacos , Traqueia/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Quinases da Família src/metabolismo
11.
Lung ; 199(6): 619-627, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34725715

RESUMO

OBJECTIVE: ß2-Adrenoceptor agonists are widely used to treat asthma because of their bronchial-dilation effects. We previously reported that isoprenaline, via the apical and basolateral ß2-adrenoceptor, induced Cl- secretion by activating cyclic AMP (cAMP)-dependent pathways in human bronchial epithelia. Despite these results, whether and how the ß2-adrenoceptor-mediated cAMP-dependent pathway contributes to pro-inflammatory cytokine release in human bronchial epithelia remains poorly understood. METHODS: We investigated ß2-adrenoceptor-mediated signaling pathways involved in the production of two pro-inflammatory cytokines, interleukin (IL)-6 and IL-8, in 16HBE14o- human bronchial epithelia. The effects of isoprenaline or formoterol were assessed in the presence of protein kinase A (PKA), exchange protein directly activated by cAMP (EPAC), Src, and extracellular signal-regulated protein kinase (ERK)1/2 inhibitors. The involvement of ß-arrestin2 was examined using siRNA knockdown. RESULTS: Isoprenaline and formoterol (both ß2 agonists) induced IL-6, but not IL-8, release, which could be inhibited by ICI 118,551 (ß2 antagonist). The PKA-specific inhibitor, H89, partially inhibited IL-6 release. Another intracellular cAMP receptor, EPAC, was not involved in IL-6 release. Isoprenaline-mediated IL-6 secretion was attenuated by dasatinib, a Src inhibitor, and PD98059, an ERK1/2 inhibitor. Isoprenaline treatment also led to ERK1/2 phosphorylation. In addition, knockdown of ß-arrestin2 by siRNA specifically suppressed cytokine release when a high concentration of isoprenaline (1 mM) was used. CONCLUSION: Our results suggest that activation of the ß2-adrenoceptor in 16HBE14o- cells stimulated the PKA/Src/ERK1/2 and/or ß-arrestin2 signaling pathways, leading to IL-6 release. Therefore, our data reveal that ß2-adrenoceptor signaling plays a role in the immune regulation of human airway epithelia.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico , Interleucina-6 , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Humanos , Interleucina-6/metabolismo , Sistema de Sinalização das MAP Quinases , Transdução de Sinais , beta-Arrestina 2
12.
Ann Transl Med ; 9(4): 313, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33708940

RESUMO

BACKGROUND: Previous studies have suggested the involvement of epithelium in modulating the contractility of neighboring smooth muscle cells. However, the mechanism underlying epithelium-derived relaxation in airways remains largely unclear. This study aimed to investigate the mechanism underlying epithelium-dependent smooth muscle relaxation mediated by neurotransmitters. METHODS: The contractile tension of Sprague-Dawley (SD) rat tracheal rings were measured using a mechanical recording system. Intracellular Ca2+ level was measured using a Ca2+ fluorescent probe Fluo-3 AM, and the fluorescence signal was recorded by a laser scanning confocal imaging system. The prostaglandin E2 (PGE2) content was measured using an enzyme-linked immunosorbent assay kit. RESULTS: We observed that the neurotransmitter acetylcholine (ACh) restrained the electric field stimulation (EFS)-induced contraction in the intact but not epithelium-denuded rat tracheal rings. After inhibiting the muscarinic ACh receptor (mAChR) or cyclooxygenase (COX), a critical enzyme in prostaglandin synthesis, the relaxant effect of ACh was attenuated. Exogenous PGE2 showed a similar inhibitory effect on the EFS-evoked contraction of tracheal rings. Moreover, ACh triggered phospholipase C (PLC)-coupled Ca2+ release from intracellular Ca2+ stores and stimulated COX-dependent PGE2 production in primary cultured rat tracheal epithelial cells. CONCLUSIONS: Collectively, this study demonstrated that ACh induced rat tracheal smooth muscle relaxation by promoting PGE2 release from tracheal epithelium, which might provide valuable insights into the cross-talk among neurons, epithelial cells and neighboring smooth muscle cells in airways.

13.
J Cell Physiol ; 235(11): 8387-8401, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32239700

RESUMO

We investigated the regulation of Cl- secretion by adrenoceptors in polarized 16HBE14o- human bronchial epithelial cells. Treatment with the nonselective ß adrenoceptor agonist isoprenaline stimulated an increase in short-circuit current (ISC ), which was inhibited by the ß adrenoceptor blocker propranolol. Treatment with procaterol, an agonist specific for the ß2 adrenoceptor subtype, stimulated a similar increase in ISC , which was inhibited by the ß2 adrenoceptor antagonist ICI 118551. Inhibitors of cystic fibrosis transmembrane conductance regulator (CFTR) and calcium-activated Cl- channel (CaCC), but not K+ channel blockers, were able to inhibit the increase in ISC . "Trimultaneous" recording of ISC and intracellular cyclic adenosine monophosphate (cAMP) and Ca2+ levels in 16HBE14o- epithelia confirmed that the ISC induced by isoprenaline or procaterol involved both cAMP and Ca2+ signaling. Our results demonstrate that ß2 adrenoceptors regulate Cl- secretion in the human airway epithelium by activating apical CFTRs and CaCCs via cAMP-dependent and intracellular Ca2+ -dependent mechanisms, respectively.


Assuntos
Canais de Cloreto/metabolismo , Cloretos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Mucosa Respiratória/metabolismo , Transporte Biológico Ativo , Brônquios/metabolismo , Linhagem Celular , Células Epiteliais/metabolismo , Humanos , Transporte de Íons/fisiologia , Transdução de Sinais/fisiologia
14.
Huan Jing Ke Xue ; 40(6): 2730-2737, 2019 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854665

RESUMO

Surficial sediments were collected from five sampling sites in the mainstream of the Shiwuli River along an urban-rural gradient in the Chaohu Lake basin during July 2017 (summer) and January 2018 (winter). The total uptake (SPUlive), abiotic uptake (SPUkill), and biotic uptake (SPUbiotic) of phosphorus by sediments were measured, and uptake responses to different carbon sources (i. e., sodium acetate, glucose, and a mixture of both) were explored quantitatively through incubation experiments. The results showed that SPUlive had obviously spatiotemporal variations across the five sites, and SPUkill was higher than that of SPUbiotic. Under no carbon added, the mean values of SPUkill were 3.016 µg·(g·h)-1 and 3.368 µg·(g·h)-1, and the average values of SPUbiotic were 0.784 µg·(g·h)-1 and 0.323 µg·(g·h)-1 in summer and winter, respectively. Moreover, significant differences were found in abiotic phosphorus uptake between the two months. In the presence of carbon addition, both the value of SPUbiotic and the contribution rate of biotic phosphorus uptake showed a distinct increase. In general, the magnitude and rate of biotic uptake of phosphorus by sediments was highest when sodium acetate was added, followed by glucose, while the effect of mixed carbon was the worst. The responses of biotic phosphorus uptake to carbon addition suggested that the uptake potential of phosphorus by sediments in Shiwuli River was restricted by the carbon availability to some degree.

15.
Nat Commun ; 10(1): 4081, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501446

RESUMO

The efficiency of sunlight-driven reduction of carbon dioxide (CO2), a process mimicking the photosynthesis in nature that integrates the light harvester and electrolysis cell to convert CO2 into valuable chemicals, is greatly limited by the sluggish kinetics of oxygen evolution in pH-neutral conditions. Current non-noble metal oxide catalysts developed to drive oxygen evolution in alkaline solution have poor performance in neutral solutions. Here we report a highly active and stable oxygen evolution catalyst in neutral pH, Brownmillerite Sr2GaCoO5, with the specific activity about one order of magnitude higher than that of widely used iridium oxide catalyst. Using Sr2GaCoO5 to catalyze oxygen evolution, the integrated CO2 reduction achieves the average solar-to-CO efficiency of 13.9% with no appreciable performance degradation in 19 h of operation. Our results not only set a record for the efficiency in sunlight-driven CO2 reduction, but open new opportunities towards the realization of practical CO2 reduction systems.

16.
Ecotoxicol Environ Saf ; 170: 9-17, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30508754

RESUMO

A novel gelatin/PVA composite nanofiber band loaded with bayberry tannin (GPNB-BT) was prepared by electrostatic spinning and crosslinking for extraction of uranium (VI) from simulated seawater. The influential factors of tannin loaded on the nanofiber band were investigated in detail. Surface morphology and fiber diameter of GPNB-BT were studied by Scanning Electron Microscopy (SEM). Functional groups of GPNB-BT were investigated by Fourier Transform Infrared Spectrometer (FTIR). The adsorption process and mechanism of uranium on GPNB-BT was characterized by Energy Dispersive X-ray (EDX) and X-ray Photoelectron Spectroscopy (XPS). The results revealed that the BT had been stably solidified on the GPNB. Compared with other tannin-immobilized membranes, the nano-network structure of GPNB-BT with 200-400 nm diameter of fibers can promote solidification of tannins and improve adsorption capacity of GPNB-BT for uranium. The maximum adsorption capacity of the GPNB-BT for uranium is 170 mg/g at the optimal pH of 5.5 in 80 mg/L of initial uranium concentration and 1.4 µg/g even at extremely low initial concentration of 3 µg/L in the simulated seawater for 24 h. The GPNB-BT with good hydraulic properties, floatability and adsorption capacity for uranium is expected to be widely used in separation and enrichment of uranium in seawater and radioactive waste water.


Assuntos
Gelatina/química , Nanofibras/química , Água do Mar/química , Taninos/química , Urânio/isolamento & purificação , Adsorção , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Myrica/química , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Mol Immunol ; 105: 205-212, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30553057

RESUMO

Carbon monoxide (CO) is an anti-inflammatory gaseous molecule produced endogenously by heme oxygenases (HOs) HO-1 and HO-2. However, the mechanisms underlying the anti-inflammatory effects of CO in the human bronchial epithelium are still not fully understood. In this study, the cationic peptide poly-l-arginine (PLA) was utilized to induce bronchial epithelial damage and subsequent pro-inflammatory cytokine release in the human bronchial epithelial cell line 16HBE14o-. Expression of both HO-1 and HO-2 after PLA exposure was examined. The polarized secretion of two pro-inflammatory cytokines, interleukin (IL)-6 and IL-8, was determined by ELISA. The anti-inflammatory effects of CO liberated from CO-releasing molecules (CORMs) were examined by both ELISA and western blot analysis. Our results indicate that PLA exposure leads to upregulation of HO-1 expression and p65 NF-κB phosphorylation, as well as IL-6 and IL-8 release. HO-1 induction by hemin or CORMs significantly suppressed IL-6 and IL-8 release. In addition, HO-1 knockdown further increased IL-6 and IL-8 release under basal and PLA-stimulated conditions. Our results thereby demonstrate that the HO-1/CO axis exerts significant anti-inflammatory activity during bronchial epithelial damage caused by cationic protein.


Assuntos
Anti-Inflamatórios/farmacologia , Brônquios/imunologia , Monóxido de Carbono/farmacologia , Heme Oxigenase-1/imunologia , Peptídeos/farmacologia , Mucosa Respiratória/imunologia , Linhagem Celular , Heme Oxigenase (Desciclizante)/genética , Heme Oxigenase (Desciclizante)/imunologia , Heme Oxigenase-1/genética , Humanos , Interleucina-6/genética , Interleucina-6/imunologia , Interleucina-8/genética , Interleucina-8/imunologia
18.
Chemosphere ; 215: 815-826, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30359951

RESUMO

In order to understand the spatial distribution characteristics, loss risk and leaching behaviors of phosphorous from exposed rocks in typical small-area of Chaohu watershed, phosphorus-rich rock was selected for conducting a series of column leaching experiments to investigate the phosphorus leaching. By simulating the intermittent cycle of acid rainfall, effects of oxalic acid on the weathering of phosphate rocks were studied. Total phosphorus contents, pH and phosphate leaching capacity from phosphorus rocks were tested in the presence of oxalic acid at different dry-wet intervals. The results indicated that the cumulative release of phosphorus increased first and then decreased with the duration of dry-wet intervals increasing. Four typical kinetic equations can describe phosphorus release from phosphate rocks with the action of oxalic acid. The best fitting models were the weight function and parabolic equation, with a mean correlation coefficient R2 of 0.9727 and 0.9941, respectively, which reached significance level. Total phosphorus (TP) leaching distribution in each column showed a tendency of gradually decreasing from top to bottom except for time interval of 5 d and 7 d. Occluded-bound P (Oc-P) is the dominant form in rocks. The change point value of rocks phosphorus is 4.11  mg kg-1 after intermittent leaching, and the phosphorus loss risk is relatively large in some rocks formations.


Assuntos
Sedimentos Geológicos/análise , Ácido Oxálico/farmacologia , Fosfatos/química , Fósforo/análise , Chuva , Movimentos da Água , China , Monitoramento Ambiental , Fósforo/química , Substâncias Redutoras/farmacologia
19.
Cell Physiol Biochem ; 49(2): 626-637, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30165347

RESUMO

BACKGROUND/AIMS: Carbon monoxide (CO) is an important gas produced endogenously by heme oxygenase (HO) that functions as an anti-inflammatory and in ion channel modulation, but the effects of CO on airway inflammation and ion transport remains unclear. METHODS: The effect of CO on cell damage- and nucleotide-induced pro-inflammatory cytokine release in primary human bronchial epithelia cells (HBE) and in the 16HBE14o- human bronchial epithelial cell line were investigated. The effects of CO on calcium- and cAMP-dependent chloride (Cl-) secretion were examined using a technique that allowed the simultaneous measurement and quantification of real-time changes in signalling molecules (cAMP and Ca2+) and ion transport in a polarised epithelium. RESULTS: CO suppressed the release of interleukin (IL)-6 and IL-8 and decreased the phosphorylation of ERK1/2 and NF-κB p65. Furthermore, CO inhibited UTP-induced increases in calcium and Cl- secretion, and forskolin-induced increases in cAMP and Cl- secretion. CONCLUSIONS: These findings suggest a novel anti-inflammatory role of CO in human bronchial epithelia via interactions with purinergic signalling pathways. Further, CO modulated both the Ca2+- and cAMP-dependent secretion of Cl-.


Assuntos
Monóxido de Carbono/farmacologia , Cloretos/metabolismo , Transporte de Íons/efeitos dos fármacos , Brônquios/citologia , Cálcio/metabolismo , Células Cultivadas , Colforsina/farmacologia , AMP Cíclico/metabolismo , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Heme Oxigenase-1/antagonistas & inibidores , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Humanos , Interleucina-6/análise , Interleucina-6/metabolismo , Interleucina-8/análise , Interleucina-8/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Compostos Organometálicos/farmacologia , Fosforilação/efeitos dos fármacos , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fator de Transcrição RelA/metabolismo
20.
Front Chem ; 6: 611, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30619820

RESUMO

Rechargeable magnesium battery has been widely considered as a potential alternative to current Li-ion technology. However, the lack of appropriate cathode with high-energy density and good sustainability hinders the realization of competitive magnesium cells. Recently, a new concept of hybrid battery coupling metal magnesium anode with a cathode undergoing the electrochemical cycling of a secondary ion has received increased attention. Mg-Na hybrid battery, for example, utilizes the dendritic-free deposition of magnesium at the anode and fast Na+-intercalation at the cathode to reversibly store and harvest energy. In the current work, the principles that take the full advantage of metal Mg anode and Na-battery cathode to construct high-performance Mg-Na hybrid battery are described. By rationally applying such design principle, we constructed a Mg-NaCrO2 hybrid battery using metal Mg anode, NaCrO2 cathode and a mixture of all-phenyl complex (PhMgCl-AlCl3, Mg-APC) and sodium carba-closo-dodecaborate (NaCB11H12) as dual-salt electrolyte. The Mg-NaCrO2 cell delivered an energy density of 183 Wh kg-1 at the voltage of 2.3 V averaged in 50 cycles. We found that the amount of electrolyte can be reduced by using solid MgCl2 as additional magnesium reservoir while maintaining comparable electrochemical performance. A hypothetical MgCl2-NaCrO2 hybrid battery is therefore proposed with energy density estimated to be 215 Wh kg-1 and the output voltage over 2 V.

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