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1.
ACS Nano ; 18(5): 4256-4268, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38265044

RESUMO

Dual-atom catalytic sites on conductive substrates offer a promising opportunity for accelerating the kinetics of multistep hydrogen and oxygen evolution reactions (HER and OER, respectively). Using MXenes as substrates is a promising strategy for depositing those dual-atom electrocatalysts, if the efficient surface anchoring strategy ensuring metal-substrate interactions and sufficient mass loading is established. We introduce a surface-modification strategy of MXene substrates by preadsorbing L-tryptophan molecules, which enabled attachment of dual-atom Co/Ni electrocatalyst at the surface of Ti3C2Tx by forming N-Co/Ni-O bonds, with mass loading reaching as high as 5.6 wt %. The electron delocalization resulting from terminated O atoms on MXene substrates, N atoms in L-tryptophan anchoring moieties, and catalytic metal atoms Co and Ni provides an optimal adsorption strength of intermediates and boosts the HER and OER kinetics, thereby notably promoting the intrinsic activity of the electrocatalyst. CoNi-Ti3C2Tx electrocatalyst displayed HER and OER overpotentials of 31 and 241 mV at 10 mA cm-2, respectively. Importantly, the CoNi-Ti3C2Tx electrocatalyst also exhibited high operational stability for both OER and HER over 100 h at an industrially relevant current density of 500 mA cm-2. Our study provided guidance for constructing dual-atom active metal sites on MXene substrates to synergistically enhance the electrochemical efficiency and stability of the energy conversion and storage systems.

2.
Neuromolecular Med ; 25(4): 501-515, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37704831

RESUMO

Activated microglia play dual roles in ischemic stroke (IS) according to its polarization states. Herein, we investigated the function of circPTP4A2 in regulating microglia polarization in IS. IS models were established by MACO/R and OGD/R treatment. TTC staining was employed to detect cerebral infarct size. Cell vitality was measured using CCK-8 assay. CD16 and CD206 levels were examined using flow cytometry. The interactions between circPTP4A2, miR-20b-5p, and YTHDF1 were analyzed by dual-luciferase reporter gene, RIP, or RNA pull-down assays. circPTP4A2 was upregulated in IS patients. circPTP4A2 knockdown alleviated MCAO/R-induced cerebral injury in mice. circPTP4A2 knockdown promoted microglia M2 polarization after OGD/R. circPTP4A2 promoted YTHDF1 expression by sponging miR-20b-5p. The promoting effect of circPTP4A2 knockdown on microglia M2 polarization was abrogated by miR-20b-5p inhibition. YTHDF1 activated the NF-κB pathway by increasing TIMP2 mRNA stability and expression. circPTP4A2 downregulation promoted microglia M2 polarization to inhibit IS development by regulating the miR-20b-5p/YTHDF1/TIMP2/NF-κB axis.


Assuntos
AVC Isquêmico , MicroRNAs , Animais , Humanos , Camundongos , AVC Isquêmico/metabolismo , Microglia , MicroRNAs/genética , NF-kappa B , Proteínas de Ligação a RNA , Inibidor Tecidual de Metaloproteinase-2
3.
Angew Chem Int Ed Engl ; 62(24): e202302689, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-36967232

RESUMO

The sluggish kinetics and mutual interference of oxygen evolution and reduction reactions in the air electrode resulted in large charge/discharge overpotential and low energy efficiency of Zn-air batteries. In this work, we designed a breathing air-electrode configuration in the battery using P-type Ca3 Co4 O9 and N-type CaMnO3 as charge and discharge thermoelectrocatalysts, respectively. The Seebeck voltages generated from thermoelectric effect of Ca3 Co4 O9 and CaMnO3 synergistically compensated the charge and discharge overpotentials. The carrier migration and accumulation on the cold surface of Ca3 Co4 O9 and CaMnO3 optimized the electronic structure of metallic sites and thus enhanced their intrinsic catalytic activity. The oxygen evolution and reduction overpotentials were enhanced by 101 and 90 mV, respectively, at temperature gradient of 200 °C. The breathing Zn-air battery displayed a remarkable energy efficiency of 68.1 %. This work provides an efficient avenue towards utilizing waste heat for improving the energy efficiency of Zn-air battery.

4.
Phys Chem Chem Phys ; 25(5): 4113-4120, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36651810

RESUMO

The recent development of some special oxygen evolution reaction (OER) electrocatalysts shows that the lattice oxygen could participate in the catalysis process via the lattice oxygen oxidation mechanism (LOM), which the provides good possibility of exploring advanced electrocatalysts that could overcome the scaling relationship in conventional catalysis processes through a traditional adsorbate evolution mechanism. In this work, we theoretically predict that, benefiting from the unhybridized O-Li orbitals and the resulting metastable Li-O-Li ligands, the lattice oxygen could be easily activated and oxidized at relatively high oxidation voltages. Thus, lithium-excess disordered rocksalts (DRX) should possess the potential for acting as active OER electrocatalysts, which catalyze through the LOM pathway. The isotope labelling experimental results show that the lattice oxygen in the DRX was activated and participated in the OER process through the LOM pathway. The typical DRX of Li1.2Fe0.4Ti0.5O2 displays obviously pH-dependent OER activity under the LOM process and shows a low overpotential of 263 mV to reach 10 mA cm-2 with long-term stability for 100 hours. The turnover frequency of Li1.2Fe0.4Ti0.5O2 is nearly 9 times that of LiFePO4 at the overpotential of 300 mV. This work opens a new chemical space for exploring efficient electrocatalysts to enhance the OER performance through the LOM pathway.

5.
Adv Mater ; 34(3): e2106354, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34699632

RESUMO

CO2 electroreduction (CO2 RR) to CO is promising for the carbon cycle but still remains challenging. Au is regarded as the most selective catalyst for CO2 RR, but its high cost significantly hinders its industrial application. Herein, the bimetallic CuInSe2 is found to exhibit an Au-like catalytic feature: i) the interaction of Cu and In orbitals induces a moderate adsorption strength of CO2 RR intermediates and favors the reaction pathway; and ii) the hydrogen evolution is energetically unfavorable on CuInSe2 , as a surface reconstruction along with high energy change will occur after hydrogen adsorption. Furthermore, the Se vacancy is found to induce an electron redistribution, slightly tune the band structure, and optimize the CO2 RR route of bimetallic selenide. Consequently, the Se-defective CuInSe2 (V-CuInSe2 ) achieves a highly selective CO production ability that is comparable to noble metals in aqueous electrolyte, and the V-CuInSe2 cathode shows a satisfactory performance in an aqueous Zn-CO2 cell. This work demonstrates that designing cost-effective catalysts with noble-metal-like properties is an ideal strategy for developing efficient electrocatalysts. Moreover, the class of transition bimetallic selenides has shown promising prospects as active and cost-effective electrocatalysts owing to their unique structural, electronic, and catalytic properties.

6.
Int Immunopharmacol ; 100: 108158, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34555642

RESUMO

BACKGROUND: Spinal cord injury (SCI) is a traumatic condition of the central nervous system , which can cause nerve injury and affect nerve regeneration, thus leading to severe dysfunction of motor and sensory pathways, and unfortunately these effects are irreversible. Inflammatory response constitutes one of the important mechanisms of spinal cord secondary injury. Geniposide (Gen) is reported to possess anti-inflammation and neuronal repair capacities. OBJECTIVES: To investigate the effect and mechanism of Gen on motor function and inflammatory response in SCI rats. METHODS: Sprague-Dawley (SD) rats were randomly grouped, and the SCI model was established by Allen's method. The motor function of rats was evaluated by the Basso, Beattie, and Bresnahan (BBB) scale. The protective effect of Gen on the injured spinal cord tissues was evaluated by measuring the water content, myeloperoxidase (MPO) activity, and levels of tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß), and IL-6. Moreover, the protein level of the inflammation-related pathway was detected by spectrometry and Western blot assays. RESULTS: Gen significantly promoted the recovery of SCI rats, decreased the edema of spinal cord tissues, reduced the area of cavity, increased the number of NF-200-positive neurons, as well as increased the number of horseradish peroxidase (HRP) retrograde tracing-positive neurons and regenerated axons with myelin sheath. Additionally, compared with the control group, the neutrophil infiltration, contents of TNF-α, IL-1ß, and IL-6, the activity of inhibitor of nuclear factor κB kinase subunit ß (IKKß) kinase, and protein levels of (nuclear factor κB) NF-κB p65 and phosphorylated inhibitor of NF-κB (p-I-κB) in the Gen experimental group were significantly decreased. CONCLUSION: Gen effectively alleviated inflammatory response after SCI by inhibiting the IKKs/NF-κB signaling pathway and promoted the recovery of motor function and axon regeneration in rats. SIGNIFICANCE: This study can provide novel insights for the early and effective intervention of SCI and confer basic data for the treatment of spinal cord secondary injury.


Assuntos
Anti-Inflamatórios/farmacologia , Quinase I-kappa B/metabolismo , Iridoides/farmacologia , NF-kappa B/metabolismo , Traumatismos da Medula Espinal/tratamento farmacológico , Regeneração da Medula Espinal/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Mediadores da Inflamação/metabolismo , Atividade Motora/efeitos dos fármacos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Transdução de Sinais , Medula Espinal/metabolismo , Medula Espinal/fisiopatologia , Medula Espinal/ultraestrutura , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia
7.
PLoS Pathog ; 17(2): e1009294, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33539420

RESUMO

Circular RNAs (circRNAs) are novel single-stranded noncoding RNAs that can decoy other RNAs to inhibit their functions. Kaposi's sarcoma (KS), caused by oncogenic Kaposi's sarcoma-associated herpesvirus (KSHV), is a highly angiogenic and invasive vascular tumor of endothelial origin commonly found in AIDS patients. We have recently shown that KSHV-encoded viral interferon regulatory factor 1 (vIRF1) induces cell invasion, angiogenesis and cellular transformation; however, the role of circRNAs is largely unknown in the context of KSHV vIRF1. Herein, transcriptome analysis identified 22 differentially expressed cellular circRNAs regulated by vIRF1 in an endothelial cell line. Among them, circARFGEF1 was the highest upregulated circRNA. Mechanistically, vIRF1 induced circARFGEF1 transcription by binding to transcription factor lymphoid enhancer binding factor 1 (Lef1). Importantly, upregulation of circARFGEF1 was required for vIRF1-induced cell motility, proliferation and in vivo angiogenesis. circARFGEF1 functioned as a competing endogenous RNAs (ceRNAs) by binding to and inducing degradation of miR-125a-3p. Mass spectrometry analysis demonstrated that glutaredoxin 3 (GLRX3) was a direct target of miR-125a-3p. Knockdown of GLRX3 impaired cell motility, proliferation and angiogenesis induced by vIRF1. Taken together, vIRF1 transcriptionally activates circARFGEF1, potentially by binding to Lef1, to promote cell oncogenic phenotypes via inhibiting miR-125a-3p and inducing GLRX3. These findings define a novel mechanism responsible for vIRF1-induced oncogenesis and establish the scientific basis for targeting these molecules for treating KSHV-associated cancers.


Assuntos
Proteínas de Transporte/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Herpesvirus Humano 8/fisiologia , Fatores Reguladores de Interferon/metabolismo , Neovascularização Patológica/patologia , RNA Circular/genética , Sarcoma de Kaposi/patologia , Proteínas Virais/metabolismo , Proteínas de Transporte/genética , Movimento Celular , Células Endoteliais da Veia Umbilical Humana , Humanos , Fatores Reguladores de Interferon/genética , MicroRNAs/genética , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/virologia , Sarcoma de Kaposi/genética , Sarcoma de Kaposi/metabolismo , Sarcoma de Kaposi/virologia , Proteínas Virais/genética
8.
Adv Mater ; 32(26): e2000607, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32459056

RESUMO

Constructing heterostructures with abundant interfaces is essential for integrating the multiple functionalities in single entities. Herein, the synthesis of NiSe2 /CoSe2 heterostructures with different interfacial densities via an innovative strategy of successive ion injection is reported. The resulting hybrid electrocatalyst with dense heterointerfaces exhibits superior electrocatalytic properties in an alkaline electrolyte, superior to other benchmarks and precious metal catalysts. Advanced synchrotron techniques, post structural characterizations, and density functional theory (DFT) simulations reveal that the introduction of atomic-level interfaces can lower the oxidation overpotential of bimetallic Ni and Co active sites (whereas Ni2+ can be more easily activated than Co2+ ) and induce the electronic interaction between the core selenides and surface in situ generated oxides/hydroxides, which play a critical role in synergistically reducing energetic barriers and accelerating reaction kinetics for catalyzing the oxygen evolution. Hence, the heterointerface structure facilitates the catalytic performance enhancement via increasing the intrinsic reactivity of metallic atoms and enhancing the synergistic effect between the inner selenides and surface oxidation species. This work not only complements the understanding on the origins of the activity of electrocatalysts based on metal selenides, but also sheds light on further surface and interfacial engineering of advanced hybrid materials.

9.
ACS Appl Mater Interfaces ; 12(7): 8115-8123, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31939657

RESUMO

Exploring economic, efficient, and corrosion-resistant oxygen electrocatalysts contributes to further development of zinc-air batteries and overall water splitting. Herein, a novel ternary spinel CoIn2Se4 nanomaterial, with Co2+ and In3+ occupying the tetrahedral and octahedral sites of the crystalline structure, has been fabricated using a facile and environment-friendly method. Moreover, CoIn2Se4 nanosheets outperform pristine CoSe2 and In2Se3 in catalyzing both oxygen evolution reaction (an overpotential of 315 mV at 10 mA cm-2) and oxygen reduction reaction (an onset overpotential of 0.88 V). The reduced charge resistance and increased active site exposure ratio contribute to the superior performance of CoIn2Se4. Moreover, density of theory (density functional theory-DFT) calculations suggest a significantly reduced reaction energy barrier after introducing indium into the spinel, and therefore the reaction kinetics are facilitated. Based on the advantages described above, CoIn2Se4 is used as the air cathode for a solid flexible zinc-air battery (FZAB). The system displays an efficient performance that outperforms the Pt@Ir/C catalyst: a significantly enhanced specific capacity of 733 mAh gZn-1, a high energy density of 931 Wh kg-1, and an excellent flexibility with long cycle life performance (over 400 cycles). The CoIn2Se4-based two-series-connected FZABs successfully power light-emitting diode (LED) screens for over 10 h. Meanwhile, CoIn2Se4 also shows a significantly enhanced hydrogen evolution reaction (HER) performance than other samples. Finally, the CoIn2Se4-based electrolyzer shows an efficient overall water-splitting performance with high stability. This work demonstrates that the indium-based ternary selenides show promising applications in developing renewable energy and water-splitting devices.

10.
ACS Appl Mater Interfaces ; 11(31): 27964-27972, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31294538

RESUMO

Exploring efficient bifunctional oxygen electrocatalysts is a critical element for developing high-power-density metal-air batteries. Here, we propose an interface and oxygen vacancy engineering strategy to integrate subtle lattice distortions, oxygen vacancies, and nanopores on the surface of NixCo1-xSe2-O interface nanocrystals, which exhibit efficient bifunctional catalytic performances for oxygen evolution and reduction. The results from X-ray absorption spectroscopy and electron spin resonance spectroscopy demonstrate that the defect structure can enlarge the number of active sites for electrocatalytic performances. Flexible Zn-air battery using NixCo1-xSe2-O as a cathode displays large specific capacity and remarkable stability even after twisting at any angle, thus showing potential for wearable and portable electronic device application. The implementation of our method provides a powerful strategy for preparing advanced catalysts for energy utilization.

11.
ACS Appl Mater Interfaces ; 11(17): 15662-15669, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30964638

RESUMO

The most challenging issue in the development of metal-air batteries is the insufficient catalytic activity of the cathode toward oxygen evolution and reduction reactions (OER/ORR). Metal-organic frameworks (MOFs) and MOF-based electrocatalysts have drawn considerable attention for the replacement of noble-metal electrocatalysts. Here, the rational design and synthesis of bimetallic CoNi-MOF nanosheets/reduced graphene oxide (rGO) hybrid electrocatalysts is reported. The CoNi-MOF nanosheets were in situ grown onto rGO assisted by the surfactant modulation. The newly developed CoNi-MOF/rGO hybrids, consisting of homogeneously distributed nanosheets encapsulated by rGO, display excellent electrocatalytic activities toward OER and ORR. The much improved bifunctional catalytic performance is ascribed to the synergy among the CoNi-MOF nanosheets and rGO, the abundant exposed active sites, and the enhanced electron conductivity. Moreover, the rechargeable Zn-air batteries with CoNi-MOF/rGO-based air electrodes display high energy density and cycling stability, demonstrating the great potential as advanced bifunctional electrocatalysis in electronic devices.

12.
Virulence ; 9(1): 1588-1600, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30272511

RESUMO

Macrophages could adhere to extracellular matrix molecules(ECM) to induce the expression of pro-inflammatory mediators and phagocytosis that contribute to the pathogenesis of pulmonary infection diseases. Fibronectin (FN) is a large glycoprotein capable of interacting with various ECM molecules produced by a variety of cell types and involved in cell attachment and chemotaxis. However, it is unknown whether FN regulates the expression of pro-inflammatory mediators and phagocytosis of macrophages in the injured lung tissue. Here, we investigated the interaction between FN and integrin ß1 in macrophages, which promotes toll-like receptor 2/4 (TLR2/TLR4) signaling pathways to enhance expression of pro-inflammatory mediators and phagocytosis by macrophages. Our results show that lipopolysaccharide (LPS), lipoteichoic acid (LTA) and peptidoglycan (PGN) significantly increase FN expression of macrophages; FN substantially enhances interleukin 6 (IL-6), tumor necrosis factor-α (TNFα), ras-related C3 botulinum toxin substrate 1/2 (Rac1/2), and cell division control protein 42 homolog (Cdc42) expression and phagocytosis of macrophages. However, FN could not enhance pro-inflammatory cytokines and phagocytosis of macrophages induced by LPS and PGN in integrin ß1-/- macrophages. Furthermore, applied integrin ß1 blocking peptide abrogated the effects that FN promotes innate immune responses of macrophages to LPS and PGN. Those data indicated that the enhanced pro-inflammatory mediators and phagocytosis of macrophages by FN-integrin ß1 signal was through co-operating with TLR2/TLR4 signaling. This study suggests that FN play an essential role in the pathogenesis of pulmonary infection disease.


Assuntos
Fibronectinas/genética , Imunidade Inata , Integrina beta1/metabolismo , Macrófagos/imunologia , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Fibronectinas/imunologia , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neuropeptídeos/metabolismo , Peptidoglicano/farmacologia , Fagocitose/imunologia , Ligação Proteica , Transdução de Sinais , Ácidos Teicoicos/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rac de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo
13.
Inflammation ; 41(3): 1073-1083, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29680908

RESUMO

Sepsis-induced myocardial injury is a well-known cause of mortality. The cholinergic anti-inflammatory pathway (CHAIP) is a physiological mechanism by which the central nervous system regulates immune response through the vagus nerve and acetylcholine; the α7-nicotinic acetylcholine receptor (α7nAChR) is the main component of CHAIP; GTS-21, a synthetic α7nAChR selective agonist, has repeatedly shown its powerful anti-inflammatory effect. However, little is known about its effect on LPS-induced myocardial injury. We investigated the protective effects of GTS-21 on lipopolysaccharide (LPS)-induced cardiomyopathy via the cholinergic anti-inflammatory pathway in a mouse sepsis model. We constructed the model of myocardial injury in sepsis mice by C57BL/6 using LPS and determined the time of LPS treatment by hematoxylin-eosin (HE) and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). C57BL/6 mice were randomized into five groups: blank control group, model group, α-bungarotoxin + LPS group, GTS-21 + LPS group, and α-bungarotoxin + GTS-21 + LPS group. The pathological results of myocardial tissue were detected by the HE method; the apoptosis rate was detected by the TUNEL method; the relative expressions of NF-κB p65, Caspase-3, Caspase-8, Bcl-2, Bax, p53, and a7nAChR were detected by real-time quantitative PCR (RT-PCR); and the protein expressions of IL-6, IL-1 ß, TNF-α, and pSTAT3 were detected by western blot. The results showed that LPS-induced myocardial pathological and apoptosis changes were significant compared with the blank group, which was reversed by GTS-21; however, pretreatment with α-bungarotoxin obviously blocked the protective effect of GTS-21. NF-κB p65, Caspase-3, Caspase-8, Bax, p53, IL-6, IL-1ß, TNF-α, and pSTAT3 were significantly increased in the model group, while a7nAChR and Bcl-2 were significantly decreased; GTS-21 treatment reversed that result, while pretreatment with α-bungarotoxin strengthened the result in the model. And pretreatment with α-bungarotoxin blocked the protective effect of GTS-21. GTS-21 can alleviate the LPS-induced damage in the heart via a7nAChR, and pretreatment with α-bungarotoxin obviously blocked the protective effect of GTS-21 on sepsis in mice.


Assuntos
Compostos de Benzilideno/farmacologia , Traumatismos Cardíacos/induzido quimicamente , Piridinas/farmacologia , Sepse/tratamento farmacológico , Animais , Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Bungarotoxinas/farmacologia , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Receptor Nicotínico de Acetilcolina alfa7/análise , Receptor Nicotínico de Acetilcolina alfa7/antagonistas & inibidores
14.
ACS Appl Mater Interfaces ; 10(17): 15150-15162, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29630332

RESUMO

A superhydrophobic ZnAl-layered double hydroxide (LDH)-La film was prepared by a hydrothermal method and further modification by laurate anions in this work. Comprehensive characterizations of this film were performed in terms of morphology, composition, structure, roughness, and wettability by scanning electronic microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, three-dimensional laser scanning confocal microscopy. The long-term corrosion protection effect of this superhydrophobic film was investigated deeply by monitoring the changes of the electrochemical impedance spectra for a long time of up to a month in 3.5 wt % NaCl solution. In the meantime, the changes of the contact angle were also recorded with the evolution of the immersion time. The result indicated that the stable superhydrophobic ZnAl-LDH-La film was able to provide efficient protection for the underlying Al substrate for a long time. In addition, the capability of the superhydrophobic surface against harsh conditions, including chemical damages and physical damages, was emphatically investigated. It was found that the superhydrophobic surface was chemically stable toward acid (pH ≥ 3), alkali, and heating, and it also exhibited high ultraviolet (UV) radiation resistance. This superhydrophobic coating maintained superhydrophobicity for 7 days of radiation in an UV chamber equipped with a 40 W UV lamp (λ = 254 nm), indicating superior ability of adapting to outdoor environment. This comprehensive investigation of the superhydrophobic ZnAl-LDH-La film is considerably helpful for researchers and engineers to get deep insight into its potential for practical applications in the field of corrosion and protection.

15.
Biomed Pharmacother ; 84: 130-138, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27643555

RESUMO

NLRP3 inflammasome plays a pivotal role in the development of acute lung injury (ALI), accelerating IL-1ß and IL-18 release and inducing lung inflammation. Resveratrol, a natural phytoalexin, has anti-inflammatory properties via inhibition of oxidation, leukocyte priming, and production of inflammatory mediators. In this study, we aimed to investigate the effect of resveratrol on NLRP3 inflammasome in lipopolysaccharide-induced ALI. Mice were intratracheally instilled with 3mg/kg lipopolysaccharide (LPS) to induce ALI. Resveratrol treatment alleviated the LPS-induced lung pathological damage, lung edema and neutrophil infiltration. In addition, resveratrol reversed the LPS-mediated elevation of IL-1ß and IL-18 level in the BAL fluids. In lung tissue, resveratrol also inhibited the LPS-induced NLRP3, ASC, caspase-1 mRNA and protein expression, and NLRP3 inflammasome activation. Moreover, resveratrol administration not only suppressed the NF-κB p65 nuclear translocation, NF-κB activity and ROS production in the LPS-treated mice, but also inhibited the LPS-induced thioredoxin-interacting protein (TXNIP) protein expression and interaction of TXNIP-NLRP3 in lung tissue. Meanwhile, resveratrol obviously induced SIRT1 mRNA and protein expression in the LPS-challenged mice. Taken together, our study suggests that resveratrol protects against LPS-induced lung injury by NLRP3 inflammasome inhibition. These findings further suggest that resveratrol may be of great value in the treatment of ALI and a potential and an effective pharmacological agent for inflammasome-relevant diseases.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Anti-Inflamatórios não Esteroides/uso terapêutico , Lipopolissacarídeos/toxicidade , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estilbenos/uso terapêutico , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Inflamassomos/antagonistas & inibidores , Inflamassomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Distribuição Aleatória , Resveratrol , Estilbenos/farmacologia
16.
FEBS J ; 283(9): 1689-700, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26929154

RESUMO

Intervertebral discs (IVDs) provide stability and flexibility to the spinal column; however, IVDs, and in particular the nucleus pulposus (NP), undergo a degenerative process characterized by changes in the disc extracellular matrix (ECM), decreased cell viability, and reduced synthesis of proteoglycan and type II collagen. Here, we investigated the efficacy and feasibility of stem cell therapy using bone marrow mesenchymal stem cells (BMSCs) over-expressing bone morphogenetic protein 7 (BMP7) to promote ECM remodeling of degenerated IVDs. Lentivirus-mediated BMP7 over-expression induced differentiation of BMSCs into an NP phenotype, as indicated by expression of the NP markers collagen type II, aggrecan, SOX9 and keratins 8 and 19, increased the content of glycosaminoglycan, and up-regulated ß-1,3-glucuronosyl transferase 1, a regulator of chondroitin sulfate synthesis in NP cells. These effects were suppressed by Smad1 silencing, indicating that the effect of BMP7 on ECM remodeling was mediated by the Smad pathway. In vivo analysis in a rabbit model of disc degeneration showed that implantation of BMSCs over-expressing BMP7 promoted cell differentiation and proliferation in the NP, as well as their own survival, and these effects were mediated by the Smad pathway. The results of the present study indicate the beneficial effects of BMP7 on restoring ECM homeostasis in NP cells, and suggest potential strategies for improving cell therapy for the treatment of disc diseases.


Assuntos
Proteína Morfogenética Óssea 7/genética , Degeneração do Disco Intervertebral/terapia , Lentivirus/genética , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Agrecanas/genética , Agrecanas/metabolismo , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Proteína Morfogenética Óssea 7/metabolismo , Condrócitos/metabolismo , Condrócitos/patologia , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Regulação da Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Glicosaminoglicanos/metabolismo , Humanos , Disco Intervertebral/metabolismo , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/genética , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Queratina-19/genética , Queratina-19/metabolismo , Queratina-8/genética , Queratina-8/metabolismo , Lentivirus/metabolismo , Células-Tronco Mesenquimais/citologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Coelhos , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Transdução de Sinais , Proteína Smad1/antagonistas & inibidores , Proteína Smad1/genética , Proteína Smad1/metabolismo
17.
Sci Rep ; 5: 17763, 2015 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-26634300

RESUMO

MicroRNAs (miRNAs) are important effectors in mediating host-pathogen interaction. In this report, coelomocytes miRNA libraries of three Japanese sea cucumbers Apostichopus japonicus were built by Illumina(®) Hiseq2000 from different time points after lipopolysaccharide challenge (at time 0 h, 6 h and 12 h). The clean data received from high throughput sequencing were used to sequences analysis. Referenced to the Strongylocentrotus purpuratus genome, 38 conserved miRNAs were found, and three miRNA candidates were predicted by software. According to the evidence resulting from the expression of AjC3, expressing levels of spu-miR-133, spu-miR-137 and spu-miR-2004 altered along with the expression of AjC3 changing at different time points after LPS injection. Thus, we speculated that the three miRNAs may have influence on A. japonicus complement C3. The spu-miR-137 and miR-137 gene family in miRBase were analyzed by bioinformatics. There is an obvious discrepancy between invertebrates and vertebrates. The first and ninth nucleotides in invertebrate miR-137 are offset compared vertebrate miR-137. Importantly, this is the first attempt to map the stage of immune response regulome in echinoderms, which might be considered as information for elucidating the intrinsic mechanism underlying the immune system in this species.


Assuntos
Complemento C3/genética , Sequenciamento de Nucleotídeos em Larga Escala , Imunidade Inata/genética , MicroRNAs/genética , Animais , Complemento C3/imunologia , Biologia Computacional , Regulação da Expressão Gênica , Genoma , Interações Hospedeiro-Patógeno/genética , MicroRNAs/biossíntese , Stichopus/genética , Strongylocentrotus purpuratus/genética , Transcriptoma/genética
18.
FEBS J ; 282(19): 3799-807, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26198480

RESUMO

Acute kidney injury (AKI), which is associated with high mortality rates, involves renal inflammation related to the activation of innate immunity. The inflammatory response in AKI involves the inflammasome, which integrates danger signals into caspase-1-activating platforms, leading to the processing and secretion of the proinflammatory cytokines interleukin (IL)-1ß and IL-18. The nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasome plays a role in the development of many diseases, including AKI. However, the mechanisms by which the NLRP3 inflammasome translates different danger signals into the expression of proinflammatory cytokines remain unclear. Here, we investigated the role of the NLRP3 inflammasome in renal injury in a cecal ligation and puncture (CLP) model of sepsis-induced AKI. CLP decreased blood pressure and increased serum creatinine levels and neutrophil infiltration into the kidney in parallel with the upregulation of NLRP3, the adaptor protein apoptosis-associated speck-like protein, and caspase-1 expression and activity in kidney tissues, and increases in the serum and kidney levels of IL-1ß and IL-18. Genetic deletion of NLRP3 reversed the CLP-induced reduction in blood pressure and increases in serum creatinine level and neutrophil infiltration, and attenuated the CLP-induced upregulation of apoptosis-associated speck-like protein, caspase-1 expression and activity, and the secretion of IL-1ß and IL-18, similarly to the effects of caspase-1 inhibition. Taken together, our results indicate that activation of the NLRP3 inflammasome contributes to the development of hypotension and the inflammatory response of AKI, suggesting its possible role as a therapeutic target for the treatment of kidney diseases.


Assuntos
Injúria Renal Aguda/fisiopatologia , Proteínas de Transporte/metabolismo , Inflamassomos/metabolismo , Injúria Renal Aguda/metabolismo , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Adaptadoras de Sinalização CARD , Proteínas de Transporte/genética , Caspase 1/metabolismo , Creatinina/sangue , Modelos Animais de Doenças , Interleucina-18/sangue , Interleucina-18/metabolismo , Interleucina-1beta/sangue , Interleucina-1beta/metabolismo , Rim/metabolismo , Rim/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR , Neutrófilos/patologia
19.
Neurosci Lett ; 595: 30-4, 2015 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25847150

RESUMO

Neuropathic pain (NP) is one of the most common complications after spinal cord injury (SCI), but no protein biomarkers has ever been introduced into clinical diagnosis. Previous studies implicated that toll-like receptor (TLR) 4 played a critical role in the development of NP in animal SCI models. Here, a total of 140 participants were recruited, 70 of them were SCI-NP subject and the rest 70 controls did not show neuropathic symptoms. TLR4 was upregulated significantly in SCI-NP patients compared with SCI-noNP subjects. Furthermore, we measured the concentrations of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), two TLR4 downstream pro-inflammatory cytokines, to assess their diagnostic values. Receiver operating characteristics (ROC) analysis revealed that TNF-α had great potential advantages to predict the progression of neuropathy, the risks of NP were strongly increased in SCI subjects with higher levels of TNF-α (odds ratio: 4.92; 95% confidence interval: 1.89-12.32). These results suggested neuro-immune activation contributed to the development of neuropathic disorder after SCI, and TNF-α could be a potential sensitive diagnostic biomarker for chronic neuropathic pain in SCI patients.


Assuntos
Neuralgia/diagnóstico , Traumatismos da Medula Espinal/fisiopatologia , Fator de Necrose Tumoral alfa/sangue , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Humanos , Interleucina-6/sangue , Masculino , Neuralgia/metabolismo , Neuralgia/fisiopatologia , RNA Mensageiro/sangue , Traumatismos da Medula Espinal/metabolismo , Fator de Necrose Tumoral alfa/genética
20.
Appl Microbiol Biotechnol ; 97(2): 599-609, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22885669

RESUMO

Wuxistatin, a novel statin and more potent than lovastatin, was converted from lovastatin by Amycolatopsis sp. (CGMCC 1149). Product I, an intermediate product, was found in the fermentation broth, and the structure analysis showed that product I had an additional hydroxyl group at the methyl group attached to C3 compared to lovastatin, which indicates that product I is one isomer of wuxistatin. Isotope tracing experiment proved that hydroxyl group of wuxistatin was provided by product I and the reaction from product I to wuxistatin was an intramolecular transfer. Hydroxylation reaction established in a cell-free system could be inhibited by CO and enhanced by ATP, Fe(2+), and ascorbic acid, which were consistent with the presumption that the hydroxylase was an induced cytochrome P450. Study on proteomics of Amycolatopsis sp. CGMCC 1149 suggested that three identified proteins, including integral membrane protein, Fe-S oxidoreductase, and GTP-binding protein YchF, were induced by lovastatin and required during hydroxylation reaction. In conclusion, bioconversion mechanism of wuxistatin by Amycolatopsis sp. CGMCC 1149 was proposed: lovastatin is firstly hydroxylated to product I by a hydroxylase, namely cytochrome P450, and then product I is rearranged to wuxistatin by isomerases.


Assuntos
Actinomycetales/metabolismo , Butiratos/metabolismo , Lovastatina/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Hidroxilação
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