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1.
Bioresour Technol ; 406: 130983, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38880266

RESUMO

In this study, a 3D CoNiO2/Co core-shell structure biochar catalyst derived from walnut shell was synthesized by hydrothermal and ion etching methods. The prepared BC@CoNi-600 catalyst exhibited exceptional peroxymonosulfate (PMS) activation. The system achieved 100 % degradation of sulfamethoxazole (SMX). The reactive oxygen species in the BC@CoNi-600/PMS system included SO4-, OH, and O2-. Density functional theory calculations explored the synergistic effects between nickel-cobalt bimetallic and carbon matrix during PMS activation. The unique 3D core-shell structure of BC@CoNi-600 features an outer nickel-cobalt bimetallic layer with exceptional PMS adsorption capacity, while protecting the zero-valence Co of the inner layer from oxidation. Based on the experimental-data, machine learning modeling mechanism, and information theory, a nonlinear modeling method was proposed. This study utilizes a machine learning approach to investigate the degradation of SMX in complex aquatic environments. This study synthesized a novel biochar-based catalyst for activated PMS and provided unique insights into its environmental applications.

2.
Chemosphere ; 332: 138860, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37150455

RESUMO

In sulfate radical-based advanced oxidation processes (SR-AOPs), high-efficiency and perdurable materials have drawn considerable interest for use as cathodes, which can effectively degrade refractory organic contaminants through the synergistic electro-activation and transition metal activation of persulfate (PS). Here, the FeCuO@C modified composite cathode (FeCuO@C/AGF) was synthesized via the solvothermal and thermal treatment method based on the CuFe-MOF-74 structure, and the electro-activation PS process (EC/FeCuO@C/AGF/PS) was developed to effectively remove atrazine (ATZ). The surface morphology, electrochemical characteristics, chemical composition, crystal structure, and electrode surface wettability of FeCuO@C/AGF were investigated. It was found that the proposed EC/FeCuO@C/AGF/PS process can successfully remove 100% of ATZ in 20 min at a low current density (2 mA cm-2) and a low PS concentration (0.4 mM), and PS is successfully activated by combining the electrical and transition metal synergistic activation. The FeCuO@C/AGF cathode exhibits outstanding catalytic functionality over a broad pH range (2-9) and remains stable over five successive cycles. Additionally, the active species involved in the reaction as well as the potential ATZ degradation reaction mechanisms and pathways are discussed. Electrochemical oxidation is a process in which both radicals (SO4·-, ·OH, and O2·-) and non-radical (1O2) participate in the degradation of ATZ. The intermediates of the ATZ degradation process were studied upon the toxicity changing, and the toxicity of the intermediates was found to be reduced during degradation. These results present a novel approach toward the establishment of an effective and reliable electrode in SR-AOPs that can efficiently treat pesticide wastewater.


Assuntos
Atrazina , Poluentes Químicos da Água , Atrazina/química , Sulfatos , Águas Residuárias , Oxirredução , Eletrodos , Poluentes Químicos da Água/análise
3.
Sci Total Environ ; 875: 162645, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36889393

RESUMO

This study aimed to further improve the degradation efficiency of pollutants by electrochemical oxidation system and reduce the consumption of electric energy. A simple method of electrochemical exfoliation was used to modify graphite felt (GF) to prepare an anode material (Ee-GF) with high degradation performance. An anode and cathode cooperative oxidation system was constructed with Ee-GF as the anode and CuFe2O4/Cu2O/Cu@EGF as the cathode to efficiently degrade sulfamethoxazole (SMX). Complete degradation of SMX was achieved within 30 min. Compared with anodic oxidation system alone, the degradation time of SMX was reduced by half and the energy consumption was reduced by 66.8 %. The system displayed excellent performance for the degradation of different concentrations (10-50 mg L-1) of SMX, different pollutants, and under different water quality conditions. In addition, the system still maintained 91.7 % removal rate of SMX after ten consecutive runs. At least 12 degradation products and seven possible degradation routes of SMX were generated in the degradation process by the combined system. The eco-toxicity of degradation products of SMX was reduced after the proposed treatment. This study provided a theoretical basis for the safe, efficient, and low energy consumption removal of antibiotic wastewater.

4.
J Hazard Mater ; 411: 125119, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-33485220

RESUMO

We reported one novel strategy via band engineering of the semiconductor support to optimize the metal-support interactions at a Mott-Schottky heterojunction interface and enhance the metal's electrocatalytic hydrodechlorination (EHDC) performance. Taking palladium-polymer carbon nitride (Pd/PCN) as a model, the band tuning of PCN by heteroatomic phosphorus (P) doping substantially boosted the EHDC of 2,4-dichlorophenol (2,4-DCP, one typical chlorinated organic pollutants (COPs)) on Pd, and a peak specific activity of 0.172 min-1 cmPd-2 was achieved by Pd/P-PCN-0.25 (0.25 reflected the P content, and denoted the mass ratio of the P source to PCN precursor used in P-PCN synthesis), quadrupling 0.041 min-1 cmPd-2 of Pd/C and outperforming most of the reported catalysts. The mechanism study revealed the P doping in PCN enabled the positive shift of its Fermi level, which weakened the Pd-PCN interactions and alleviated the electron excess of Pd in Pd/PCN. The P-PCN in Pd/P-PCN-0.25 with the ideal band structure evoked a Pd electronic state that maximized EHDC efficiency. Further investigation into the intermediate products of EHDC on Pd/P-PCN and the biological safety of the 2,4-DCP-contaminated water after EHDC treatment demonstrated the EHDC over our catalyst was environmental-benignity for COPs abatement.

5.
ACS Appl Mater Interfaces ; 13(3): 4072-4083, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33438993

RESUMO

We present an enhanced catalytic efficiency of palladium (Pd) nanoparticles (NPs) for the electrocatalytic hydrodechlorination (EHDC) reaction by incorporating the tetraethylammonium chloride (TEAC) ligand into the surface of NPs. Both experimental and theoretical analyses reveal that the surface-adsorbed TEAC is converted to molecular amine (primarily triethylamine) under reductive potentials, forming a strong ligand-Pd interaction that is beneficial to the EHDC kinetics. Using the EHDC of 2,4-dichlorophenol (2,4-DCP), a dominant persistent pollutant identified by the U.S. Environmental Protection Agency, as an example, the Pd/amine composite delivers a mass activity of 2.32 min-1 gPd-1 and a specific activity of 0.16 min-1 cm-2 at -0.75 V versus Ag/AgCl, outperforming Pd and most of the previously reported catalysts. The mechanistic study reveals that the amine ligand offers three functions: the H+-pumping effect, the electronic effect, and the steric effect, providing a favorable environment for the generation of reactive hydrogen radicals (H*) for hydrogenolysis of the C-Cl bond. It also weakens the adsorption strength of EHDC products, alleviating their poisoning on Pd. Investigation into the intermediate products of EHDC on Pd/amine and the biological safety of the 2,4-DCP-contaminated water after EHDC treatment demonstrates that EHDC on Pd/amine is environmentally benign for halogenated organic pollutant abatement. This work suggests that the tuning of NP catalysis using facile ligand post-treatment may lead to new strategies to improve EHDC for environmental remediation applications.

6.
Anticancer Drugs ; 31(10): 997-1003, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33065690

RESUMO

Lung cancer always ranks first in the number of cancer deaths every year, accounting for 18.4% of total cancer deaths in 2018. Metastasis is the main cause of death in lung cancer patients. The identification of bioactive components of traditional Chinese medicine is very important for the development of novel reagents against non-small cell lung cancer (NSCLC). Rosthorin A has originated from Rabdosia rosthornii (Diels) Hara which excerpts from 'Chinese materia medica', and is known to have 'clear heat phlegm' properties in the folk. Little is known about the biological functions and mechanisms of Rosthorin A in cancer cells at present. The role of EMT in metastasis of a tumor cell is self-evident. Slug is an important EMT inducer, which is related to the development of lung cancer. Cell growth, clone assay, cell migration, cell invasion, and protein expression, and NSCLC transplanted tumor growth were performed in A549, H1299, and H1975 cells. Rosthorin A significantly inhibited the growth of NSCLC cells, it could prolong the survival of nude mice. Rosthorin A inhibited the migration and invasion of A549, H1299, and H1975 cells. Rosthorin A up-regulated E-cadherin expression level and down-regulated the expression of ß-catenin, N-cadherin, vimentin, Slug, and Twist. Rosthorin A could promote the expression of E-cadherin and inhibit the development of EMT by downregulating Slug, to inhibit the development and metastasis of NSCLC cells. In summary, Rosthorin A could be used as a promising candidate for the treatment of NSCLC patients with recurrence and metastasis.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Polifenóis/farmacologia , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Camundongos Endogâmicos BALB C , Proteínas Nucleares/metabolismo , Polifenóis/química , Fatores de Transcrição da Família Snail/metabolismo , Proteína 1 Relacionada a Twist/metabolismo , Vimentina/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/metabolismo
7.
Nanoscale ; 12(2): 843-850, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31830178

RESUMO

We demonstrated that heteroatomic nitrogen (N) doping of graphene can significantly enhance the performance of the graphene-palladium nanoparticle composite catalyst (N/G-Pd) in the electrocatalytic hydrodechlorination (EHDC) reaction. Specifically at -0.80 V (vs. Ag/AgCl), the N/G-430-Pd (prepared at 430 °C, pyridinic/pyrrolic-N-rich) and N/G-900-Pd (prepared at 900 °C, pyridinic/graphitic-N-rich) with equivalent total N content delivered the apparent rate constants (kobs) of 0.28 and 0.20 min-1 molPd-1 in removing 2,4-dichlorophenol, much higher than the 0.13 min-1 molPd-1 of the C-Pd. Additionally, we identified the determinant role of pyrrolic-N in boosting EHDC from the linear relationship between kobs-N and the pyrrolic-N content in the catalyst. Combined experimental and DFT analyses revealed that the positive effect of N doping originated from the strong N-Pd interactions, which modulated the Pd electronic structure and its interactions with the reactant and EHDC products (phenol and Cl-). The pyrrolic N-Pd bond was favorable as it could balance the reactant adsorption and the product desorption.

8.
Molecules ; 24(22)2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31703459

RESUMO

This study describes the chemical constituents of Albiziae Cortex and their ability to ameliorate steatosis and promote proliferation and anti-oxidation in vitro. Together, five known lignan glycosides, (7S,8R)-erythro-syringylglycerol-ß-O-4'-sinapyl ether 9-O-ß-D-glucopyranoside (1), (+)-lyoniresinol-9'-O-gluco-side (2), (-)-lyoniresinol-9'-O-glucoside (3), picraquassioside C (4), and icariside E5 (5), were isolated from the Albiziae Cortex. Their structures were elucidated by extensive NMR and high-resolution mass spectrometry analysis and compared with reported data. Oil Red O staining results revealed that compounds 1, 2, and 3 attenuated lipid accumulation and lipid metabolic disorders in FFAs (oleate/palmitate, 2:1 ratio, 0.3 mM)-exposed HepG2 cells. The Cell Counting Kit 8 (CCK-8) assay results revealed that compounds 1 and 5 can significantly promote human umbilical vein endothelial cell (HUVEC) proliferation; meanwhile, these compounds did not exhibit significant cytotoxicity against HUVECs. In addition, 2',7'-dichlorofluorescein diacetate (DCFH-DA) staining results revealed that high glucose (HG)-induced reactive oxygen species (ROS) production was abolished by compounds 1, 2, and 3. This is the first report of the isolation of lignan skeletons from the genus Albizzia julibrissin with the ability to ameliorate steatosis and promote proliferation and anti-oxidation activities.


Assuntos
Albizzia/química , Antioxidantes , Proliferação de Células/efeitos dos fármacos , Fígado Gorduroso/tratamento farmacológico , Lignanas/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana , Humanos , Espectrometria de Massas , Ressonância Magnética Nuclear Biomolecular , Ácido Oleico/metabolismo , Oxirredução , Ácido Palmítico/metabolismo
9.
Int J Mol Sci ; 20(18)2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31533227

RESUMO

Cardiovascular complications are a major leading cause of mortality in patients suffering from type 2 diabetes mellitus (T2DM). Vascular endothelial dysfunction is a core pathophysiological event in the early stage of T2DM and eventually leads to cardiovascular disease. Vaccarin (VAC), an active flavonoid glycoside extracted from vaccariae semen, exhibits extensive biological activities including vascular endothelial cell protection effects. However, little is known about whether VAC is involved in endothelial dysfunction regulation under high glucose (HG) or hyperglycemia conditions. Here, in an in vivo study, we found that VAC attenuated increased blood glucose, increased glucose and insulin tolerance, relieved the disorder of lipid metabolism and oxidative stress, and improved endothelium-dependent vasorelaxation in STZ/HFD-induced T2DM mice. Furthermore, in cultured human microvascular endothelial cell-1 (HMEC-1) cells, we showed that pretreatment with VAC dose-dependently increased nitric oxide (NO) generation and the phosphorylation of eNOS under HG conditions. Mechanistically, VAC-treated HMEC-1 cells exhibited higher AMPK phosphorylation, which was attenuated by HG stimulation. Moreover, HG-triggered miRNA-34a upregulation was inhibited by VAC pretreatment, which is in accordance with pretreatment with AMPK inhibitor compound C (CC). In addition, both reactive oxygen species (ROS) scavenger N-acetyl-L-cysteine (NAC) and VAC abolished HG-evoked dephosphorylation of AMPK and eNOS, increased miRNA-34a expression, and decreased NO production. These results suggest that VAC impedes HG-induced endothelial dysfunction via inhibition of the ROS/AMPK/miRNA-34a/eNOS signaling cascade.


Assuntos
Angiopatias Diabéticas/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Glicosídeos/farmacologia , Substâncias Protetoras/farmacologia , Animais , Diabetes Mellitus Tipo 2/metabolismo , Angiopatias Diabéticas/tratamento farmacológico , Angiopatias Diabéticas/etiologia , Angiopatias Diabéticas/patologia , Modelos Animais de Doenças , Glicosídeos/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , MicroRNAs , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Substâncias Protetoras/química , Espécies Reativas de Oxigênio/metabolismo
10.
Nanoscale ; 11(34): 15892-15899, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31464326

RESUMO

Identifying the rate-determining step over the catalysts and clarifying the underlying mechanisms are crucial for maximizing the electrocatalytic hydrodechlorination (EHDC) efficiency for detoxification of the chlorophenol pollutants in water. Here, monodisperse palladium nanoparticles (Pd NPs) separately supported on carbon (C) and titanium nitride (TiN) were synthesized as two model catalysts. The support effects on EHDC efficiency, kinetics and current efficiency towards 2,4-dichlorophenol (2,4-DCP), and the electronic structure of Pd and its binding strengths with 2,4-DCP, phenol and Cl- (the primary EHDC product) were investigated by experimental and density functional theory (DFT) analyses. The low current efficiency (<30%) of both catalysts and the good description of EHDC kinetics by the Langmuir-Hinshelwood model suggest that the 2,4-DCP coverage on Pd, rather than the well-known adsorbed hydrogen generation, determines EHDC efficiency. Furthermore, the superior EHDC efficiency on TiN-Pd (96.4% vs. 80.9% on C-Pd), coupled with the weakened adsorption of 2,4-DCP and phenol on TiN-supported Pd, demonstrates that the 2,4-DCP coverage is largely influenced by phenol due to its poisoning effect by blocking active sites, and phenol desorption is the rate-determining step of EHDC on the catalyst. The support TiN enables alleviation of the phenol poisoning by modulating the electronic structure of Pd. The d band center of Pd can serve as a potential descriptor of EHDC efficiency, and its optimization for balancing 2,4-DCP and phenol adsorption should be an effective strategy to enhance EHDC.

11.
Acta Parasitol ; 64(3): 520-527, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31087260

RESUMO

INTRODUCTION: Trichinellosis is a severe zoonosis involving the activation of inflammatory cells, accompanied by the prominent expressions of proinflammatory cytokines in the host. Semen vaccariae, the seeds of Vaccaria segetalis (Neck.) Garcke. ex Asch. (Caryophyllaceae), is a famous traditional herb that is rich in vaccaria n-butanol extract (VNE). Vaccarin is one major active component of VNE, and it is reported in the treatment of stranguria disease. Hypaphorine is another main active component of VNE and has good anti-inflammatory effect, whereas the potential bioactivity of VNE in trichinellosis treatment is still unknown. MATERIALS AND METHODS: This study was designed to evaluate the potential anthelmintic and anti-inflammatory activity of VNE toward T. spiralis infection. ICR mice were used to assess the effect of VNE on repression larvae and adult worms in vivo. Immunohistochemistry analysis was performed to evaluate the expression levels of IL-1ß, IL-6, TNF-α, and COX-2. RESULTS: Our results showed that VNE could effectively depress the expressions of proinflammatory cytokines, including IL-1ß, IL-6, TNF-α, and COX-2. The adult worms were decreased by 79.53%, while the muscle larvae were diminished by 77.70% as compared to the control. CONCLUSION: These results demonstrated that VNE may be a promising therapeutic agent against the inflammation and diseases caused by T. spiralis infection.


Assuntos
Anti-Inflamatórios/administração & dosagem , Extratos Vegetais/administração & dosagem , Triquinelose/tratamento farmacológico , Vaccaria/química , Animais , Anti-Inflamatórios/análise , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/imunologia , Humanos , Interleucina-6/genética , Interleucina-6/imunologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Extratos Vegetais/análise , Trichinella/efeitos dos fármacos , Trichinella/fisiologia , Triquinelose/genética , Triquinelose/imunologia , Triquinelose/parasitologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
12.
Talanta ; 130: 356-62, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25159421

RESUMO

Intracellular pH plays a pivotal role in various biological processes. In eukaryotic cells, lysosomes contain numerous enzymes and proteins exhibiting a variety of activities and functions at acidic pH (4.5-5.5), and abnormal variation in the lysosomal pH causes defects in lysosomal function. Thus, it is important to investigate lysosomal pH in living cells to understand its physiological and pathological processes. In this work, we designed a one-step synthesized rhodamine derivative (RM) with morpholine as a lysosomes tracker, to detect lysosomal pH changes with high sensitivity, high selectivity, high photostability and low cytotoxicity. The probe RM shows a 140-fold fluorescence enhancement over a pH range from 7.4 to 4.5 with a pKa value of 5.23. Importantly, RM can detect the chloroquine-induced lysosomal pH increase and monitor the dexamethasone-induced lysosomal pH changes during apoptosis in live cells. All these features demonstrate its value of practical application in biological systems.


Assuntos
Apoptose , Neoplasias da Mama/diagnóstico , Diagnóstico por Imagem , Corantes Fluorescentes , Lisossomos/química , Rodaminas , Feminino , Humanos , Concentração de Íons de Hidrogênio , Força Próton-Motriz , Espectrometria de Fluorescência , Células Tumorais Cultivadas
13.
Chem Commun (Camb) ; 50(43): 5790-2, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24756360

RESUMO

A novel coumarin-based fluorescent probe, P-CM, for quantitative detection of nitroxyl (HNO) was developed. P-CM exhibits a selective response to HNO over other biological reductants and was also applied for quantitative detection of HNO in bovine serum with satisfactory results.


Assuntos
Corantes Fluorescentes/química , Óxidos de Nitrogênio/sangue , Óxidos de Nitrogênio/química , Água/química , Animais , Bovinos , Substâncias Redutoras/química , Espectrometria de Fluorescência
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