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1.
J Environ Manage ; 347: 119119, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37804630

RESUMO

Advanced oxidation processes (AOPs) based on peracetic acid (PAA) has been extensively concerned for the degradation of organic pollutants. In this study, metallic iron-modified sludge biochar (Fe-SBC) was employed to activate PAA for the removal of sulfamethoxazole (SMX). The characterization results indicated that FeO and Fe2O3 were successfully loaded on the surface of the sludge biochar (SBC). Fe-SBC/PAA system achieved 92% SMX removal after 30 min. The pseudo-first-order kinetic reaction constant of the Fe-SBC/PAA system was 7.34 × 10-2 min-1, which was 2.4 times higher than the SBC/PAA system. The degradation of SMX was enhanced with increasing the Fe-SBC dosage and PAA concentration. Apart from Cl-, NO3- and SO42- had a negligible influence on the degradation of SMX. Quenching experiments and electron paramagnetic resonance (EPR) techniques identified the existence of reactive species, of which CH3C(O)OO•, 1O2, and O2•- were dominant reactive species in Fe-SBC/PAA system. The effect of different water matrices on the removal of SMX was investigated. The removal of SMX in tap water and lake water were 79% and 69%, respectively. Four possible pathways for the decay of SMX were presented according to the identification of oxidation products. In addition, following the ecological structure-activity relationship model (ECOSAR) procedure and the germination experiments with lettuce seeds to predict the toxicity of the intermediates. The acute and chronic ecotoxicity of SMX solution was dramatically diminished by processing with Fe-SBC/PAA system. In general, this study offered a prospective strategy for the degradation of organic pollutants.


Assuntos
Ácido Peracético , Poluentes Químicos da Água , Sulfametoxazol , Ferro , Esgotos , Poluentes Químicos da Água/análise , Oxirredução , Água , Peróxido de Hidrogênio
2.
Clin Exp Immunol ; 214(1): 50-60, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-37455659

RESUMO

As the largest proportion of myeloid immune cells in tumors, macrophages play an important role in tumor growth and regression according to their different phenotypes, thus reprogramming macrophages has become a new research direction for cancer immunotherapy. Yeast-derived whole ß-glucan particles (WGPs) can induce M0 macrophages to differentiate into M1 macrophages and convert M2 macrophages and tumor-associated macrophages (TAMs) into M1 macrophages. In vitro, studies have confirmed that WGP-treated macrophages increase the activating receptors in natural killer cells (NK cells) and enhance the cytotoxicity of NK cells. The extracellular regulated protein kinases (ERK) signaling pathway is involved in WGP-mediated regulation of the macrophage phenotype. Further in vivo studies show that oral WGP can significantly delay tumor growth, which is related to the increased proportion of macrophages and NK cells, the macrophage phenotype reversal, and the enhancement of NK cell immune function. NK-cell depletion reduces the therapeutic efficacy of WGP in tumor-bearing mice. These findings revealed that in addition to T cells, NK cells also participate in the antitumor process of WGP. It was confirmed that WGP regulates the macrophage phenotype to regulate NK-cell function.


Assuntos
Neoplasias , beta-Glucanas , Animais , Camundongos , Saccharomyces cerevisiae , beta-Glucanas/farmacologia , beta-Glucanas/metabolismo , Macrófagos , Células Matadoras Naturais , Imunidade
3.
Sci Total Environ ; 859(Pt 1): 160001, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36368385

RESUMO

Highly efficient and stable heterogeneous catalysts were desired to activate periodate (PI) for sustainable pollution control. Herein, iron-nitrogen-carbon catalyst was synthesized using a facile molten-salts mediated pyrolysis strategy (denoted as FeNC-MS) and employed to activate PI for the degradation of acetaminophen (ACE). Compared with iron-nitrogen-carbon catalyst prepared by direct pyrolysis method (marked as FeNC), FeNC-MS exhibited superior catalytic activity due to its large specific surface area (1600 m2 g-1) and the abundance of FeNx sites. The batch experiments revealed that FeNC/PI process achieved 37 % ACE removal within 20 min, while ACE removal in FeNC-MS/PI process was 98 % under the identical conditions. Integrated with electron paramagnetic resonance tests, quenching experiments, chemical probe identification, and electrochemical experiments, we demonstrated that FeNC-MS-PI complexes-mediated electron transfer was the predominant mechanism for the oxidation of ACE. Further analysis disclosed that FeNx sites in FeNC-MS were the main active sites for the activation of PI. Additionally, FeNC-MS/PI process exhibited significant resistance to humic acid and background electrolyte, and avoided the secondary pollution imposed by Fe leaching. The possible degradation pathways of ACE were proposed. The germination experiments of lettuce seeds showed that the ecotoxicity of ACE solution was significantly reduced after treatment with FeNC-MS/PI process. Overall, this study provided a facile strategy for the synthesis of efficient iron-nitrogen-carbon catalysts and gained fundamental insight into the mechanism of PI activation by iron-nitrogen-carbon catalysts for pollutants degradation.


Assuntos
Carbono , Nitrogênio , Nitrogênio/química , Carbono/química , Ferro/química , Acetaminofen/química , Peróxidos/química , Sais
4.
Cancer Immunol Immunother ; 71(8): 2007-2028, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34982184

RESUMO

Although therapeutic cancer vaccines have been gaining substantial ground, the development of cancer vaccines is impeded because of the undegradability of delivery systems, ineffective delivery of tumor antigens and weak immunogenicity of adjuvants. Here, we made use of a whole glucan particle (WGP) to encapsulate ovalbumin (OVA), thereby formulating a novel cancer vaccine. Results from in vitro experiments showed that WGP-OVA not only induced the activation of bone marrow-derived macrophages (BMDMs) including driving M0 BMDM polarization to the M1 phenotype, upregulating the costimulatory molecules and inducing the generation of cytokines, but also facilitated antigen presentation. After oral administration of the WGP-OVA formulation to mice with OVA-expressing tumors, these particles can increase tumor-infiltrating OVA-specific CD8+ CTLs and repolarize tumor-associated macrophages (TAMs) toward M1-like phenotype, which led to delayed tumor progression. These findings revealed that WGP could serve as both an antigen delivery system and an adjuvant system for promising cancer vaccines.


Assuntos
Vacinas Anticâncer , Neoplasias , Adjuvantes Imunológicos , Administração Oral , Animais , Glucanos/farmacologia , Macrófagos , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/terapia , Ovalbumina
5.
Ecotoxicol Environ Saf ; 196: 110550, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32247244

RESUMO

Iron/zinc (Fe/Zn), phosphoric acid (H3PO4) or in combination (Fe/Zn + H3PO4) modified sludge biochar (SBC) were prepared and tested in this study to adsorb fluoroquinolones antibiotics including ciprofloxacin (CIP), norfloxacin (NOR) and ofloxacin (OFL) from water. Fe/Zn + H3PO4-SBC had an increased surface area (SBET), total pore volume (Vtot), mesoporous volume (Vmes), pore diameter (Dp) and oxygen-containing functional groups. It exhibited superior adsorption performance for CIP, NOR and OFL with the maximum adsorption amount of 83.7, 39.3, 25.4 mg g-1, respectively. Pseudo-second kinetic and Freundlich isotherm model presented the better fitting. The results of models and characterization analysis in combination indicated that physisorption and chemisorption, including pore filling, hydrogen bonding, π-π interaction, electrostatic interaction and functional groups complexation on a heterogeneous surface were the dominant process and mechanism. Liquid film diffusion was the main rate-limiting step. The adsorption process of CIP, NOR and OFL onto Fe/Zn + H3PO4-SBC were a spontaneous endothermic process. This study demonstrated that Fe/Zn + H3PO4 modified SBC exhibited high adsorption capacity, which was a promising adsorbent for fluoroquinolones as well as for other antibiotics effective removal from waters.


Assuntos
Antibacterianos/análise , Carvão Vegetal/química , Fluoroquinolonas/análise , Esgotos/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Ferro/química , Cinética , Modelos Teóricos , Ácidos Fosfóricos/química , Propriedades de Superfície , Zinco/química
6.
PLoS One ; 14(6): e0218114, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31188870

RESUMO

A novel approach was employed to load α-Fe2O3 and α-FeOOH onto sewage sludge biochar (SBC) with the purpose of efficient nickel (Ni) removal. A high Ni(II) adsorption capacity of 35.50 mg·g-1 in 100 ppm Ni(II) solution with 10 mg modified sewage sludge biochar (MSBC) was achieved. The adsorption kinetic and isotherm were fitted well by the pseudo-second-order model and the Langmuir model, respectively. The optimal pH was found around a neutral pH of 7. The adsorption mechanisms of Ni(II) onto MSBC were described as the synergistic effects of electrostatic attraction, ion exchange, inner-sphere complexation and co-precipitation. The initial rapid adsorption phenomenon could be attributed to electrostatic attraction and ion exchange, and then inner-sphere complexation and co-precipitation acted as a crucial role in the following step. The remarkable performance of MSBC provides an effective waste utilization approach to simultaneous sewage sludge recycle and Ni removal from aqueous solution.


Assuntos
Carvão Vegetal/química , Compostos Férricos/química , Níquel/química , Esgotos/química , Poluentes Químicos da Água/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Eliminação de Resíduos Líquidos/métodos , Água/química
7.
Int J Clin Exp Med ; 8(4): 5591-600, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26131142

RESUMO

AIMS: To investigate the roles of matrine in regulating immune functions and its effect on the proliferation of leukemic cells. METHODS: Human leukemia K562, OUN-1, HL-60, U937, K562/AO2 cell lines and primary leukemic cells were used to detect the NKG2D ligands (NKG2DL) expression such as MICA/B, ULBP-1, ULBP-2, ULBP-3, and NK cells receptor NKG2D, CD158a, CD158b were detected by flow cytometry. Cell cytotoxic activity of human NK cells and CIK cells against K562 leukemia cells was detected using CFSE/PI double staining. Pro-inflammatory cytokines and adhesion molecules in K562 or NK cells supernatant after matrine treatment were detected. RESULTS: Matrine could upregulate the expression of NKG2DL on leukemic cell lines, and primary leukemic cells and enhance the NK and CIK cytotoxicity targeted to K562 cells. After matrine treatment, pro-inflammatory cytokines and adhesion molecular such as IL-6, IL-1, IL-2, IL-4, IL-5, GRO and TNF-α in K562 cells supernatant were significantly decreased (P < 0.05). Flow cytometry analysis showed that the NKG2D expression was up-regulated significantly as well as the CD158a and CD158b expression decreased after treatment with different concentration of matrine in a dose-dependent manner in K562 cells. A significant decrease of supernatant concentrations of IL-1α, IL-5, IL-6, IL-10, IFN-γ, GRO and TNF-α in NK cells was also observed after exposure to the matrine. CONCLUSION: Matrine regulates immune functions to inhibit the proliferation of leukemic cells.

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