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In-plane heterostructures has attracted considerable interest due to exceptional electron transport properties, high specific surface area, and abundant active sites. However, synthesis of in-plane SnS2-SnO2 heterostructures are rarely reported, and the deep investigation of the fine structure on reactivity is of great significance. Here, we propose partial in-situ oxidation strategy to construct the in-plane SnS2-SnO2 heterostructures and the surface properties, the ratio of two components can be finely tuned by precisely adjusting the treatment temperature. In particular, the SnS2-SnO2 heterostructures formed after annealing of SnS2 nanosheets at 350 °C exhibits a unique electronic structure and surface properties due to rich grain boundaries, which exhibits excellent gas sensing performance to H2S (Ra/Rg = 169.81 for 5 ppm H2S at 160 °C, fast response and recovery dynamic (41/101 s), excellent reliability (σ = 0.01) and sensing stability (φ = 0.11 %)). Notably, the in-plane heterostructures endow the material with abundant grain boundaries and effectively regulates the electronic structure of the Sn p-orbital, which facilitate the formation of active oxygen species (O-(ad)), thus contributing to the sensing performance. Our work provides a promising platform to design in-plane heterostructures for various advanced applications.
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A Pt nanoparticle-immobilized WO3 material is a promising candidate for catalytic reactions, and the surface and electronic structure can strongly affect the performance. However, the effect of the intrinsic oxygen vacancy of WO3 on the d-band structure of Pt and the synergistic effect of Pt and the WO3 matrix on reaction performance are still ambiguous, which greatly hinders the design of advanced materials. Herein, Pt-decorated WO3 nanosheets with different electronic metal-support interactions are successfully prepared by finely tuning the oxygen vacancy structure of WO3 nanosheets. Notably, Pt-modified WO3 nanosheets annealed at 400 °C exhibit excellent benzene series (BTEX) sensing performance (S = 377.33, 365.21, 348.45, and 319.23 for 50 ppm ethylbenzene, benzene, toluene, and xylene, respectively, at 140 °C), fast response and recovery dynamics (10/7 s), excellent reliability (σ = 0.14), and sensing stability (φ = 0.08%). Detailed structural characterization and DFT results reveal that interfacial Ptδ+-Ov-W5+ sites are recognized as the active sites, and the oxygen vacancies of the WO3 matrix can significantly affect the d-band structure of Pt nanoparticles. Notably, Pt/WO3-400 with improved surface oxygen mobility and medium electronic metal-support interaction facilitates the activation and desorption of BTEX, which contributes to the highly efficient BTEX sensing performance. Our work provides a new insight for the design of high-performance surface reaction materials for advanced applications.
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Derivados de Benzeno , Benzeno , Óxidos , Oxigênio , Platina , Tungstênio , Tungstênio/química , Platina/química , Óxidos/química , Oxigênio/química , Benzeno/química , Derivados de Benzeno/química , Nanoestruturas/química , Xilenos/química , Nanopartículas Metálicas/química , Tolueno/química , Técnicas Eletroquímicas/métodos , Teoria da Densidade FuncionalRESUMO
We investigated possible protective effects of chlorogenic acid (CGA) against cyclophosphamide (CP) induced hepatic injury in mice. We measured aminotransferase alanine transaminase (ALT) and aspartate transaminase (AST) levels in the serum. We assayed catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) in hepatic tissue. We assessed expression of nuclear transcription factor 2 (Nrf2) and Kelch sample related protein-1 (keap1) proteins in hepatic tissues using immunohistochemistry. The relative mRNA expression levels of heme oxygenase-1 (HO-1), NADH quinone oxidoreductase 1 (NQO1), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were determined using quantitative real-time polymerase chain reaction (qRT-PCR). Hematoxylin & eosin staining was used to assess liver histopathology. We found that administration of CGA prior to induction of injury by CP decreased serum ALT, AST and MDA expressions in hepatic tissue, while CAT, SOD, GSH and GSH-Px concentrations were increased. We found that hepatocytes of animals administered CGA gradually returned to normal morphology. CGA increased the protein expression of Nrf2 in murine hepatic tissue. Administration of CGA up-regulated mRNA expression levels of HO-1, NQO1, TNF-α and IL-6 in hepatic tissue. CGA exhibited a marked protective effect on CP induced liver injury in mice.
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Doença Hepática Crônica Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas , Camundongos , Animais , Ácido Clorogênico/farmacologia , Ácido Clorogênico/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6 , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/patologia , Fígado , Alanina Transaminase/metabolismo , Superóxido Dismutase/metabolismo , Ciclofosfamida/toxicidade , RNA Mensageiro/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Doença Hepática Induzida por Substâncias e Drogas/patologia , Estresse OxidativoRESUMO
Pd-based materials have received remarkable attention and exhibit excellent H2 sensing performance due to their superior hydrogen storage and catalysis behavior. However, the synergistic effects originated from the decoration of Pd on a metal oxide support to boost the sensing performance are ambiguous, and the deep investigation of metal support interaction (MSI) on the H2 sensing mechanism is still unclear. Here, the model material of Pd nanoparticle-decorated WO3 nanosheet is synthesized, and individual fine structures can be achieved by treating it at different temperatures. Notably, the Pd-WO3-300 materials display superior H2 sensing performance at a low working temperature (110 °C), with a superior sensing response (Ra/Rg = 40.63 to 10 ppm), high sensing selectivity, and anti-interference ability. DFT calculations and detailed structural investigations confirm that the moderate MSI facilitates the generation of high mobility surface O2- (ad) species and a proper ratio of surface Pd0-Pd2+ species, which can significantly boost the desorption of intermediate PdHx species at low temperatures and contribute to enhanced sensing performance. Our work illustrates the effect of MSI on sensing performance and provides insight into the design of advanced sensing materials.
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Temperatura Baixa , Hidrogênio , Temperatura , Catálise , OxigênioRESUMO
Bergenin (BG) is a polyphenolic substance which has therapeutic potential in the treatment of diabetic nephropathy (DN), a common complication of type II diabetes. However, the mechanisms underlying these effects remain unclear. We studied the protective effects and mechanisms of BG in DN mice, focusing on the TLR4/MyD88/NF-κB signalling pathway. C57BL/6 J mice were used as experiments (n=60), and 10 animals were randomly selected as normal control. The DN model was developed by administering an intraperitoneal injection of streptozotocin (40 mg/kg BW for three days) and a high-fat diet (n=50). BG (20, 40, and 80 mg/kg BW, once a day) was administered orally for four weeks. After BG treatment, the food and water intake of DN mice decreased, blood glucose levels decreased, and insulin resistance reduced. As a result, serum LDL-C, TC, and TG levels decreased; HDL-C levels increased; SOD, CAT, and GSH-Px levels decreased; and MDA levels increased. BG administration reduced AST, ALT, BUN, and CRE levels and inflammatory factors (including TNF-α, MCP-1, IL-1ß, and IL-6). Histopathology revealed a significant improvement in pathological damage to the liver, kidney, and spleen of mice treated with BG, and TLR4, MyD88, and NF-κB p65 were down-regulated at both mRNA and protein levels in the BG-treated group. Based on these results, BG therapeutic type II DN by hypoglycaemia, improving liver and kidney function, and anti-oxidative stress; reducing inflammation; and inhibiting the TLR4/MyD88/NF-κB signalling pathway. The results of this study suggest that BG can be used as an effective treatment for type II DN.
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Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Ratos , Camundongos , Animais , NF-kappa B/metabolismo , Nefropatias Diabéticas/patologia , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Ratos Sprague-Dawley , Diabetes Mellitus Experimental/complicações , Camundongos Endogâmicos C57BLRESUMO
Sodium ion batteries (SIBs) attract most of the attention as alterative secondary battery systems for future large-scale energy storage and power batteries due to abundance resource and low cost. However, the lack of anode materials with high-rate performance and high cycling-stability has limited the commercial application of SIBs. In this paper, Cu7.2S4@N, S co-doped carbon (Cu7.2S4@NSC) honeycomb-like composite structure was designed and prepared by a one-step high-temperature chemical blowing process. As an anode material for SIBs, Cu7.2S4@NSC electrode exhibited an ultra-high initial Coulomb efficiency (94.9%) and an excellent electrochemical property including a high reversible capacity of 441.3 mAh g-1 after 100 cycles at 0.2 A g-1, an excellent rate performance of 380.4 mAh g-1 even at 5 A g-1, and a superior long-cycle stability with a capacity retention rate of approximately 100% after 700 cycles at 1A g-1.
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This research demonstrated the protective effect and possible mechanism of the Sophora viciifolia extract (SVE) against acetaminophen-induced liver injury in mice. The levels of ALT and AST in the serum and antioxidant enzyme activity in the liver were measured. We used immunohistochemistry to detect CYP2E1, Nrf2, and Keap1 protein expression in the liver. The mRNA expression in the liver of TNF-α, NF-κB, and IL-6, Nrf2 and its downstream genes HO-1 and GCLC were measured by qRT-PCR. We found that SVE could decrease the ALT and AST levels, promote the activities of SOD, CAT, GSH-Px, and GSH, and ameliorate pathological liver lesions. SVE could down-regulate the mRNA expression of inflammatory factors and up-regulate Nrf2, HO-1 and GCLC. SVE reduced the protein expression of the CYP2E1 and increased the Nrf2 and Keap1. SVE has been shown to have a protective effect against APAP-induced liver injury, possibly through activation of the Keap1-Nrf2 pathway.
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Acetaminofen , Doença Hepática Crônica Induzida por Substâncias e Drogas , Camundongos , Animais , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Acetaminofen/efeitos adversos , Citocromo P-450 CYP2E1/genética , Citocromo P-450 CYP2E1/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Frutas/metabolismo , Antioxidantes/farmacologia , RNA MensageiroRESUMO
Cardiac hypertrophy is a well-established risk factor for cardiovascular mortality worldwide. According to a recent study, hypoxia-induced endoplasmic reticulum stress regulating long noncoding RNA (HypERlnc) is significantly reduced in the left ventricular myocardium of heart failure (HF) patients compared with healthy controls. However, the effect of HypERlnc on hypertrophy is unclear. In this study, the expression level of HypERlnc in serum of patients with chronic HF was analyzed. Moreover, the cardioprotective effect and mechanism of HypERlnc against cardiomyocyte hypertrophy were explored. Here, the level of HypERlnc expression was reduced in serum of patients with HF and in Angiotensin II (Ang II)-stimulated AC16 cells. HypERlnc overexpression could reduce cell size and inhibit expression of hypertrophy genes (ANP, BNP, and ß-MHC) in the Ang II-induced cardiomyocyte hypertrophy. Meanwhile, HypERlnc could improve the Ang II-induced energy metabolism dysfunction and mitochondrial damage via upregulating PGC-1α/PPARα signaling pathway. Furthermore, it is found that SIRT1 SUMOylation mediated the HypERlnc-induced inhibition of cardiomyocyte hypertrophy and the improvement of energy metabolism. Taken together, this study suggests that HypERlnc suppresses cardiomyocyte hypertrophy and energy metabolism dysfunction via enhancing SUMOylation of SIRT1 protein. HypERlnc is a potential novel molecular target for preventing and treating pathological cardiac hypertrophy.
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Insuficiência Cardíaca , Hormônios Peptídicos , Humanos , Miócitos Cardíacos/metabolismo , Angiotensina II/metabolismo , PPAR alfa/metabolismo , Sirtuína 1/metabolismo , Sumoilação , Cardiomegalia/metabolismo , Hormônios Peptídicos/metabolismoRESUMO
Long noncoding RNA-Myosin heavy chain associated RNA transcript (LncRNA-MHRT) has been reported to prevent pathological cardiac hypertrophy. However, the underlying inhibition mechanism has not been fully elucidated. Further, whether MHRT inhibits hypertrophy by regulating post-translational modification of certain proteins remains unclear. Therefore, this study aims to find potential role of MHRT in inhibiting cardiac hypertrophy via regulating modification of certain proteins. Here, Angiotensin II (Ang II) -treated neonatal rat cardiomyocytes and transverse aortic constriction (TAC) mice were used to investigate the effect and mechanism of MHRT in cardiac hypertrophy in vitro and in vivo. Moreover, the regulatory effects of MHRT on SUMOylation of NAD-dependent protein deacetylase sirtuin-1 (SIRT1), peroxisome proliferator-activated receptor γ coactivator-1 α (PGC-1α)/peroxisome proliferator-activated receptor-α (PPARα), specificity protein 1 (SP1)/histone deacetylase 4 (HDAC4) pathway were investigated. Here, we found that MHRT improved heart function by attenuating pathological cardiac hypertrophy in vivo and in vitro. MHRT also promoted the SUMOylation of SIRT1 protein that activated PGC1-α/PPAR-α pathway. Furthermore, MHRT enhanced SUMOylation of SIRT1 by upregulating SP1/HDAC4. Our findings suggested that SUMOylation of SIRT1 could mediate the protective effect of MHRT in cardiac hypertrophy. The new regulatory pathway provides a potential new therapeutic target for pathological cardiac hypertrophy.
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RNA Longo não Codificante , Sirtuína 1 , Animais , Cardiomegalia/patologia , Camundongos , Miócitos Cardíacos , Cadeias Pesadas de Miosina/genética , PPAR alfa/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , RNA Longo não Codificante/metabolismo , Ratos , Sirtuína 1/genética , Sirtuína 1/metabolismo , SumoilaçãoRESUMO
Lysozyme, an important antibacterial protein, is an enzyme that cleaves the glycosidic bond between N-acetylmuramic acid and N-acetylglucosamine of peptidoglycan in cell walls. The novel lysozyme was purified and characterized from Chinese Lueyang black-bone silky fowl (CBSF) egg white, and its N-terminal amino acid sequence, enzymatic properties, and antibacterial activity were investigated. The CBSF lysozyme was purified using adsorption chromatography, ammonium sulfate precipitation, ion exchange chromatography, and size-exclusion chromatography. The purification fold and yield were 3.28 and 14.69%, respectively. The purified lysozyme was revealed as a single protein band with SDS-PAGE and had a MALDI-TOF/TOF molecular weight of 14305.57 Da and a final specific activity of 3.49 × 105 U/mg protein using Micrococcus lysodeikticus as a substrate. The optimum temperature and pH of the lysozyme were 50 °C and 6.0, respectively. The 20 N-terminal amino acid residues of the purified lysozyme were determined to be KVFGRCELAAAMKRHGLDNY, showing some homology to the N-terminus of the odontophoridae egg white lysozyme. The purified lysozyme exerted a potent antimicrobial activity toward indicator microorganisms, including Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 25923, and Escherichia coli ATCC 25922. However, its inhibition of gram-negative activity was weaker than that of the Gram-positive bacteria.