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1.
J Environ Manage ; 351: 119837, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38154225

RESUMEN

Phosphate concentrations in eutrophic surface waters are usually low, and efficient removal of low concentration phosphate remains a challenge. In this study, Ca-doped LaMnO3 synthesized at doping ratios, designated as CaxLa1-xMnO3 (x = 0, 0.2, 0.4, 0.7), were compared. It was found that, the adsorption capacity of Ca0.4La0.6MnO3 material reached 63.01 mg/g at pH = 5, increased by 63.6% over the undoped LaMnO3 perovskite. For long-term adsorption, Ca0.4La0.6MnO3 could constantly adsorb phosphate to avoid phosphate accumulation (<0.05 mg/L). This proves that Ca0.4La0.6MnO3 has the ability to control dynamic water eutrophication. Characterization and density functional theory results confirmed that CaxLa1-xMnO3 can increase the content of mesopores and oxygen vacancies, providing additional active sites. This reduces the adsorption energy of the La site, promotes electron transfer, and increases its affinity. It provides a new method for removing low-concentration phosphates.


Asunto(s)
Fosfatos , Contaminantes Químicos del Agua , Adsorción , Fosfatos/química , Agua , Concentración de Iones de Hidrógeno , Cinética
2.
Front Immunol ; 14: 1175764, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37304307

RESUMEN

Background: A series of novel inflammation-related indexes has been confirmed to be efficient indicators of human immune and inflammatory status, with great potential as predictors for a variety of diseases. However, the association between inflammation-related indexes and sex hormones in the general population remained uncertain. Methods: We incorporated data from the NHANES 2013-2016 survey of American adults. On the basis of distribution and comparison analysis, we chose to undertake separate analyses of men and women (including premenopausal and postmenopausal groups). Multivariable weighted linear regression models, eXtreme Gradient Boosting (XGBoost) models, generalized linear analysis, stratified models, logistic regression models and sensitivity analysis were utilized to assess the relationships between inflammation-related indexes and sex hormones. Results: Total 9372 participants out of 20146 were fitted into our research. We conducted separate gender analysis due to different distribution. Multivariable weighted linear regression indicated every component of the inflammation-related index was negatively correlated with at least one component of the male hormone indexes. However, SII, NLR, PPN, and NC were associated positively with female estradiol. XGBoost identify SII, PLR and NLR were the critical indexes on sex hormones. Inflammation-related indexes was associated with Testosterone deficiency in male and postmenstrual group and associated with Excessive Estradiol in premenstrual group. Finally, the subgroup analysis revealed that the association between sex hormones and inflammatory indicators was prominent in American adults over the age of 60 or those with BMI (>28 kg/m2). Conclusion: In all, inflammation-related indexes act as independent risks associated with sex hormone alterations and metabolic disorder in both genders. Using multiple models, we revealed the relative importance of inflammation-related indexes. Subgroup analysis also identified the high-risk population. More prospective and experimental research should be conducted to validate the results.


Asunto(s)
Hormonas Esteroides Gonadales , Inflamación , Humanos , Femenino , Adulto , Masculino , Encuestas Nutricionales , Estudios Transversales , Estudios Prospectivos , Estradiol
3.
Analyst ; 148(12): 2855-2860, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37248854

RESUMEN

Early diagnosis of acute myocardial infarction (AMI) can significantly reduce mortality, which can be achieved by the highly sensitive detection of AMI-specific cardiac troponin I (cTnI) biomarkers. Herein a highly sensitive and portable photoelectrochemical (PEC) immunoassay for the detection of cTnI was innovatively fabricated based on an efficient photocurrent response of Cu2O coupling with a split-type enzymatic biocatalytic precipitation reaction with a digital multimeter readout. Initially, Cu2O cubic nanomaterials with a good photocurrent response were obtained by facile green room temperature synthesis and dropped on fluorine-doped tin oxide (FTO) plates as photoactive materials (Cu2O/FTO). In the presence of target cTnI, horseradish peroxidase (HRP) on the detection antibody catalyzes the substrate 4-chloro1-naphthol (4-CN) to produce insoluble precipitates of benzo-4-chlorohexadienone (4-CD) on Cu2O/FTO with the assistance of H2O2, resulting in a decrease in the photocurrent of the Cu2O/FTO electrode. To make the whole inspection process more concise and efficient, we used a flashlight and a digital multimeter as the excitation light source and reading device for the PEC sensing system, respectively. Under the optimal conditions of immunoreaction time, pH, and loading, the photocurrent of Cu2O/FTO decreased with increasing target cTnI concentration with a limit of detection (LOD) of 4.7 pg mL-1 in the operating range of 0.01-10 ng mL-1. It is of interest that the developed portable PEC immunoassay is also capable of detecting cTnI in human serum samples with acceptable accuracy compared to the reference cTnI enzyme-linked immunosorbent assay (ELISA) method while maintaining portability and sensitivity.


Asunto(s)
Técnicas Biosensibles , Infarto del Miocardio , Humanos , Troponina I , Peróxido de Hidrógeno , Inmunoensayo/métodos , Ensayo de Inmunoadsorción Enzimática , Anticuerpos , Límite de Detección , Infarto del Miocardio/diagnóstico , Técnicas Biosensibles/métodos , Técnicas Electroquímicas
4.
Int J Biol Macromol ; 240: 124451, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37062379

RESUMEN

The hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) has attracted much attention, as GVL can be used as biofuel, green solvent, and platform chemical. Inspired by Stöber method, various lignin-metal coordinated colloidal nanospheres (LCS) from lignin and cetyltrimethylammonium bromide (CTAB) were synthesized in which the metal ions (Co2+) replace formaldehyde as the crosslinker. The characterization of the catalyst revealed that alkali lignin was first self-assembled with CTAB through electrostatic attraction to form a lignin polymer, the subsequent addition of metal ions (Co2+) promoted the aggregation of lignin polymers and generated the LCS. Increasing calcination temperature for LCS resulted in the Co2+ being reduced to metallic Co. The lignin-metal coordinated colloidal nanospheres calcined at 500 °C possess both CoO and metallic Co active sites, which effectively accelerated the hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) than simplex metallic Co active sites. A 99.8 % yield of GVL with 100 % LA conversion was obtained after 60 min reaction time at 200 °C and 2 MPa H2.


Asunto(s)
Lignina , Nanosferas , Hidrogenación , Lignina/química , Agua , Cetrimonio , Ácidos Levulínicos/química , Metales
5.
Pharmaceutics ; 15(4)2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37111687

RESUMEN

The glucagon-like peptide-1 (GLP-1) is a peptide with incretin activity and plays an important role in glycemic control as well as the improvement of insulin resistance in type 2 diabetes mellitus (T2DM). However, the short half-life of the native GLP-1 in circulation poses difficulties for clinical practice. To improve the proteolytic stability and delivery properties of GLP-1, a protease-resistant modified GLP-1 (mGLP-1) was constructed with added arginine to ensure the structural integrity of the released mGLP-1 in vivo. The model probiotic Lactobacillus plantarum WCFS1 was chosen as the oral delivery vehicle with controllable endogenous genetic tools driven for mGLP-1 secretory constitutive expression. The feasibility of our design was explored in db/db mice which showed an improvement in diabetic symptoms related to decreased pancreatic glucagon, elevated pancreatic ß-cell proportion, and increased insulin sensitivity. In conclusion, this study provides a novel strategy for the oral delivery of mGLP-1 and further probiotic transformation.

6.
ACS Appl Mater Interfaces ; 15(13): 16942-16952, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36961428

RESUMEN

La-based metal oxide materials are environmentally friendly and show promise for phosphate adsorption. A series of Al-doped perovskite oxides, such as LaFexAl1-xO3, were prepared using a facile citric acid-assisted sol-gel method. The characterization results demonstrated that with optimized Al doping, there was a significant increase in the specific surface area and increased defect content of perovskite oxide LaFexAl1-xO3. Adsorption experiments showed that the performance of phosphate removal by LaFexAl1-xO3 was largely enhanced due to the improved adsorption capacity, which is maximum eight times higher compared with control perovskites prepared under neutral conditions. The mass transfer rate for adsorption was considerably boosted with phosphate removal within the initial 15 min. Spectroscopy analysis and density functional theory calculation results showed that the process of phosphate removal by the Al-doped perovskite oxides LaFexAl1-xO3 involved electrostatic interactions, an inner-sphere complex, and surface oxygen vacancies, among which the creation of oxygen vacancies caused by the Al doping was the predominant mechanism for reducing the bonding barrier during adsorption and generating adsorption sites. The results enable the development of a green and efficient perovskite adsorbent with a La-based perovskite material for phosphorus removal.

7.
Polymers (Basel) ; 15(4)2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36850113

RESUMEN

Replacing fossil-based polymers with renewable bio-based polymers is one of the most promising ways to solve the environmental issues and climate change we human beings are facing. The production of new lignocellulose-based polymers involves five steps, including (1) fractionation of lignocellulose into cellulose, hemicellulose, and lignin; (2) depolymerization of the fractionated cellulose, hemicellulose, and lignin into carbohydrates and aromatic compounds; (3) catalytic or thermal conversion of the depolymerized carbohydrates and aromatic compounds to platform chemicals; (4) further conversion of the platform chemicals to the desired bio-based monomers; (5) polymerization of the above monomers to bio-based polymers by suitable polymerization methods. This review article will focus on the progress of bio-based monomers derived from lignocellulose, in particular the preparation of bio-based monomers from 5-hydroxymethylfurfural (5-HMF) and vanillin, and their polymerization methods. The latest research progress and application scenarios of related bio-based polymeric materials will be also discussed, as well as future trends in bio-based polymers.

8.
J Colloid Interface Sci ; 632(Pt A): 87-94, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36410297

RESUMEN

Electrocatalytic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) was examined as an alternative to thermocatalytic methods in which two-dimensional (2D) cobalt-metal-organic framework (Co-MOF, ZIF-L-Co) nanoplate arrays were prepared on nickel foam (NF) and then transformed into hierarchical porous Co3O4 nanostructures by chemical etching and low temperature annealing to form electrode materials. Hierarchical porous nanoarrays formed during synthesis enlarged the surface area of the as-prepared catalysts introduced a large number of defects and exposed active sites leading to reduced charge diffusion, improved mass transfer and efficient HMF oxidation. Co3O4/NF electrode materials were able to achieve a current density of 10 mA·cm-2 at an overpotential of 105 mV in 1 M KOH with 10 mM HMF, which was reduced by 175 mV compared with water oxidation. Electrocatalytic oxidation experiments afforded 100 % HMF conversion and 96.7 % FDCA yields with a minimum 96.5 % faradaic efficiency at 1.43 V vs RHE. The proposed MOF-structured synthesis method fundamentally reduces charge diffusion, improves mass transfer of electrodes and is generally applicable to fabrication of hierarchical porous nanostructured materials.


Asunto(s)
Estructuras Metalorgánicas , Furaldehído , Níquel
9.
Polymers (Basel) ; 15(23)2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38231969

RESUMEN

Hydrochar is considered to be a good adsorbent for the separation of metal ions from aqueous solutions. However, the yield of hydrochar from raw straw is generally low, because the hydrothermal carbonization occurs via dehydration, polymerization, and carbonization. In this work, various hydrochar samples were prepared from rice straw with nitrogen and phosphorus salt; moreover, toilet sewage was used instead of nitrogen, and phosphorus salt and water were used to promote the polymerization and carbonization process. The modified carbon was characterized using XRD, XPS, SEM, and FTIR, and the adsorption capacity was investigated. A significant increase in hydrochar yield was observed when toilet sewage was used as the solvent in the hydrothermal carbonization process. The adsorption capacity of N/P-doped rice straw hydrochar for Cd2+ and Zn2+ metal ions was 1.1-1.4 times higher than that those using the rice straw hydrochar. The Langmuir models and pseudo-second-order models described the metal adsorption processes in both the single and binary-metal systems well. The characterization results showed the contribution of the surface complexation, the electrostatic interaction, the hydrogen bond, and the ion exchange to the extraction of Cd2+ and Zn2+ using N/P-doped rice straw hydrochar.

10.
Nanomaterials (Basel) ; 14(1)2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38202477

RESUMEN

Zn-BTC (H3BTC refers to 1, 3, 5-benzoic acid) MOF was used as a self-template and a zinc source to prepare ZnS/NiS2 with a layered heterogeneous structure as a promising electrode material using cation exchange and solid-phase vulcanization processes. The synergistic effect of the two metal sulfides enhances the application of ZnS/NiS2. And the high specific surface area and abundant active sites further promote the mass/charge transfer and redox reaction kinetics. In the three-electrode system, the specific capacitance was as high as 1547 F/g at a current density of 1 A/g, along with satisfactory rate capability (1214 F/g at 6 A/g) and cycling performance. Coupled with activated carbon (AC), the prepared hybrid device (ZnS/NiS2 as the positive electrode and AC as the negative electrode) (ZnS/NiS2/AC) can be operated under a potential window of 1.6 V and provides a high energy density of 26.3 Wh/kg at a power density of 794 W/kg. Notably, the assembled ZnS/NiS2//AC showed little capacity degradation after 5000 charge/discharge cycles.

11.
Artículo en Inglés | MEDLINE | ID: mdl-35954579

RESUMEN

The catalytic transfer hydrogenation of biomass-derived furfural to furfuryl alcohol under mild conditions is an attractive topic in biorefinery. Herein, mesoporous Zr-containing hybrids (Zr-hybrids) with a high surface area (281.9−291.3 m2/g) and large pore volume (0.49−0.74 cm3/g) were prepared using the biomass-derived 5-sulfosalicylic acid as a ligand, and they were proven to be highly efficient for the Meerwein−Ponndorf−Verley reduction of furfural to furfuryl alcohol at 110 °C, with the highest furfuryl alcohol yield reaching up to 97.8%. Characterizations demonstrated that sulfonic and carboxyl groups in 5-sulfosalicylic acid molecules were coordinated with zirconium ions, making zirconium ions fully dispersed, thus leading to the formation of very fine zirconia particles with the diameter of <2 nm in mesoporous Zr-hybrids. The interaction between the 5-sulfosalicylic acid ligands and zirconium ions endowed mesoporous Zr-hybrids with relatively higher acid strength but lower base strength, which was beneficial for the selective reduction of furfural to furfuryl alcohol. A recycling study was performed over a certain mesoporous Zr-hybrid, namely meso-Zr-SA15, demonstrating that the yield and selectivity of furfuryl alcohol remained almost unchanged during the five consecutive reaction cycles. This study provides an optional method to prepare hybrid catalysts for biomass refining by using biomass-derived feedstock.


Asunto(s)
Furaldehído , Circonio , Bencenosulfonatos , Biomasa , Furanos , Hidrogenación , Ligandos , Salicilatos
12.
Artículo en Inglés | MEDLINE | ID: mdl-35805431

RESUMEN

Adsorption is an efficient technology for removing phosphorus from wastewater to control eutrophication. In this work, MgO-modified biochars were synthesized by a solvent-free ball milling method and used to remove phosphorus. The MgO-modified biochars had specific surface areas 20.50-212.65 m2 g-1 and pore volume 0.024-0.567 cm3 g-1. The as-prepared 2MgO/BC-450-0.5 had phosphorus adsorption capacities of 171.54 mg g-1 at 25 °C and could remove 100% of phosphorus from livestock wastewater containing 39.51 mg L-1 phosphorus. The kinetic and isotherms studied show that the pseudo-second-order model (R2 = 0.999) and Langmuir models (R2 = 0.982) could describe the adoption process well. The thermodynamic analysis indicated that the adsorption of phosphorus on the MgO-modified biochars adsorbent was spontaneous and endothermic. The effect of pH, FTIR spectra and XPS spectra studies indicated that the phosphorus adsorption includes a protonation process, electrostatic attraction and precipitation process. This study provides a new strategy for biochar modification via a facile mechanochemical method.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Adsorción , Carbón Orgánico , Cinética , Óxido de Magnesio , Fósforo , Solventes , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis
13.
J Hazard Mater ; 436: 129109, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35594674

RESUMEN

In coal-combustion energy production, presence of water vapor in flue gas causes catalyst deactivation and leads to the release of large quantities of volatile organic compounds (VOCs). In this study, design of a low-temperature, hydrophobic catalyst for flue gas purification was achieved by modifying support material with inorganic siloxane. Introduction of 5% water vapor into simulated flue gas at 300 °C reduced oxidation efficiency for o-xylene removal by 26% with unmodified MnOx/γ-Al2O3 catalyst, whereas with modified catalyst MnOx-Si0.9/γ-Al2O3 oxidation efficiency was reduced by only 5%. MnOx-Si0.9/γ-Al2O3 exhibited stable catalytic efficiency for o-xylene gas oxidation containing water vapor for over 200 min. Water-resistance of the catalyst was effective for removal of multi-coal combustion pollutants (Hg0 and NO) and moreover, hydrophobicity of the catalyst led to a reduction in surface sulfate deposition, thereby lowering toxicity of SO2 from simulated flue gas. DRIFTS analysis showed that the hydrophobic catalyst surface not only reduces water adsorption, but also promotes water volatilization. Based on molecular adsorption energies, catalyst support modification with siloxane inhibits water adsorption and promotes organic adsorption and thus provides a new strategy for preparing water-resistant catalysts for flue gas purification.

14.
Environ Sci Pollut Res Int ; 28(39): 55725-55735, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34138434

RESUMEN

In this work, hydrothermal leaching was applied to simulated soils (clay minerals vermiculite, montmorillonite, and kaolinite) and actual soils (Terunuma, Japan) to generate organic acids with the objective to develop an additive-free screening method for determination of Sr in soil. Stable strontium (SrCl2) was adsorbed onto soils for the study, and ten organic acids (citric, L(+)-tartaric, succinic, oxalic, pyruvic, formic, glycolic, lactic, acetic, and propionic) were evaluated for leaching Sr from simulated soils under hydrothermal conditions (120 °C to 200 °C) at concentrations up to 0.3 M. For strontium-adsorbed vermiculite (Sr-V), 0.1 M citric acid was found to be effective for leaching Sr at 150 °C and 1 h treatment time. Based on these results, the formation of organic acids from organic matter in Terunuma soil was studied. Hydrothermal treatment of Terunuma soil produced a maximum amount of organic acids at 200 °C and 0.5 h reaction time. To confirm the possibility for leaching of Sr from Terunuma soil, strontium-adsorbed Terunuma soil (Sr-S) was studied. For Sr-S, hydrothermal treatment at 200 °C for 0.5 h reaction time allowed 40% of the Sr to be leached at room temperature, thus demonstrating an additive-free method for screening of Sr in soil. The additive-free hydrothermal leaching method avoids calcination of solids in the first step of chemical analysis and has application to both routine monitoring of metals in soils and to emergency situations.


Asunto(s)
Suelo , Estroncio , Japón , Investigación
15.
Pharmacol Res ; 169: 105685, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34022398

RESUMEN

Erlotinib, an EGFR tyrosine kinase inhibitor has been introduced into cancer chemotherapy. However, the therapeutic effects of erlotinib in hepatocellular carcinoma (HCC) remain vaguely understood. Our previous study found that a hypoxia-mediated PLAGL2-EGFR-HIF-1/2α signaling loop in HCC decreased response to erlotinib. The current study has demonstrated that the combination of erlotinib and 2ME2 exerted synergistic antitumor effects against HCC. Further investigation showed that erlotinib increased the expression level of EGFR, HIF-2α, and PLAGL2, which contributes to the insensitivity of hypoxic HCC cells to erlotinib. The simultaneous exposure to 2ME2 effectively inhibited the expression level of EGFR, HIF-2α, and PLAGL2 that was induced by erlotinib. This contributes to the synergistic effect of the two therapeutic agents. Furthermore, the combination of erlotinib and 2ME2 induced apoptosis and inhibited the stemness of hypoxic HCC cells. Our findings potentially explain the mechanism of HCC insensitivity to erlotinib and provide a new strategy of combining EGFR and HIF1/2α inhibitors for HCC treatment.


Asunto(s)
2-Metoxiestradiol/uso terapéutico , Antineoplásicos/uso terapéutico , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Carcinoma Hepatocelular/tratamiento farmacológico , Proteínas de Unión al ADN/metabolismo , Clorhidrato de Erlotinib/uso terapéutico , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Proteínas de Unión al ARN/metabolismo , Transducción de Señal/efectos de los fármacos , Factores de Transcripción/metabolismo , 2-Metoxiestradiol/administración & dosificación , 2-Metoxiestradiol/farmacología , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Sinergismo Farmacológico , Receptores ErbB/metabolismo , Clorhidrato de Erlotinib/administración & dosificación , Clorhidrato de Erlotinib/farmacología , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Ratones Endogámicos BALB C , Ratones Endogámicos NOD , Ratones Desnudos , Trasplante de Neoplasias
16.
Anal Bioanal Chem ; 413(1): 235-244, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33048173

RESUMEN

A portable photothermal immunoassay based on Au-coated magnetic Fe3O4 core-shell nanohybrids (Au-Fe3O4) was developed for point-of-care (POC) testing of lipoprotein-associated phospholipase A2 (Lp-PLA2) on a digital near-infrared (NIR) thermometer. Au-Fe3O4 photothermal materials were first synthesized through reverse micelle method, and then functionalized with polyclonal rabbit anti-human Lp-PLA2 antibody. A sandwiched immunoreaction was carried out in polyclonal mouse anti-human Lp-PLA2 antibody-coated microplate using Au-Fe3O4-labeled antibody as the detection antibody. With formation of sandwich-type immunocomplex, the captured Au-Fe3O4 on the plate converted the light into heat under an 808-nm laser irradiation (1.5 W cm-2), thereby resulting in the increasing temperature of the detection solution. The temperature variations relative to surrounding temperature was determined on a portable NIR thermometer. Several labeling protocols with gold nanoparticle, Fe3O4 nanoparticle, or Au-Fe3O4 nanohybrids were investigated for determination of Lp-PLA2 and improved analytical features were achieved with the core-shell Au-Fe3O4 nanohybrids. Under optimum conditions, Au-Fe3O4-based immunoassay exhibited good photothermal responses for the detection of Lp-PLA2 with a dynamic linear range of 0.01-100 ng mL-1 at a low detection limit of 8.6 pg mL-1. Good reproducibility and intermediate precision were less than 9.7%. Other biomarkers or proteins did not interfere with responses of this system. An acceptable accuracy was acquired for analysis of human serum sample between Au-Fe3O4-based photothermal immunoassay and commercialized human Lp-PLA2 ELISA kit.


Asunto(s)
Óxido Ferrosoférrico/química , Oro/química , Inmunoensayo/métodos , Lipoproteínas/química , Nanoestructuras/química , Fosfolipasas A2/química , Sistemas de Atención de Punto , Termómetros , Rayos Infrarrojos , Límite de Detección , Prueba de Estudio Conceptual , Reproducibilidad de los Resultados
17.
Sci Total Environ ; 764: 142805, 2021 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-33082048

RESUMEN

Volatile organic compounds (VOCs) emitted from coal-fired flue gas of thermal power plants have reached unprecedented levels due to lack of understanding of reaction mechanisms under industrial settings. Herein, inhibition mechanisms for catalytic oxidation of o-xylene in simulated coal-fired flue gas are elucidated with in-situ and ex-situ spectroscopic techniques considering the presence of impurity components (NO, NH3, SO2, H2O). MnCe oxide catalysts prepared at Mn: Ce mass ratios of 6:4 are demonstrated to promote 87% o-xylene oxidation at 250 °C under gas hourly space velocities of 60,000 h-1. Reaction intermediates on the catalyst surface are revealed to be o-benzoquinones, benzoates, and formate and they were stably formed under O2/N2 atmospheres. When either NO or NH3 was introduced into the simulated flue gas, the formed species shifted toward formate in minutes, which indicated that changes in catalyst surface chemistry are directly related to impurity components. Presence of NH3 in the simulated flue gas inhibited o-xylene oxidation by reducing Mn and lowering Brønsted acidity of the catalyst. Impurity components associated with pollutant removal processes (Hg0 oxidation and selective catalytic reduction of NO) lowered o-xylene removal efficiency. Presence of o-xylene in the flue gas had little effect on the efficiency of pollutant removal processes. Layered catalytic beds located downstream from Hg0/NO pollutant removal processes are proposed to lower VOC emissions from coal-fired flue gases of thermal power plants in industrial settings.

18.
Hepatology ; 73(2): 674-691, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32335942

RESUMEN

BACKGROUND AND AIMS: Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide, hence a major public health threat. Pleomorphic adenoma gene like-2 (PLAGL2) has been reported to play a role in tumorigenesis. However, its precise function in HCC remains poorly understood. APPROACH AND RESULTS: In this study, we demonstrated that PLAGL2 was up-regulated in HCC compared with that of adjacent nontumorous tissues and also correlated with overall survival times. We further showed that PLAGL2 promoted HCC cell proliferation, migration, and invasion both in vitro and in vivo. PLAGL2 expression was positively correlated with epidermal growth factor receptor (EGFR) expression. Mechanistically, this study demonstrated that PLAGL2 functions as a transcriptional regulator of EGFR and promotes HCC cell proliferation, migration, and invasion through the EGFR-AKT pathway. Moreover, hypoxia was found to significantly induce high expression of PLAGL2, which promoted hypoxia inducible factor 1/2 alpha subunit (HIF1/2A) expression through EGFR. Therefore, this study demonstrated that a PLAGL2-EGFR-HIF1/2A signaling loop promotes HCC progression. More importantly, PLAGL2 expression reduced hepatoma cells' response to the anti-EGFR drug erlotinib. PLAGL2 knockdown enhanced the response to erlotinib. CONCLUSIONS: This study reveals the pivotal role of PLAGL2 in HCC cell proliferation, metastasis, and erlotinib insensitivity. This suggests that PLAGL2 can be a potential therapeutic target of HCC.


Asunto(s)
Carcinoma Hepatocelular/genética , Proteínas de Unión al ADN/metabolismo , Clorhidrato de Erlotinib/farmacología , Neoplasias Hepáticas/genética , Proteínas de Unión al ARN/metabolismo , Factores de Transcripción/metabolismo , Adulto , Anciano , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Proteínas de Unión al ADN/genética , Progresión de la Enfermedad , Resistencia a Antineoplásicos/genética , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Clorhidrato de Erlotinib/uso terapéutico , Retroalimentación Fisiológica , Femenino , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Estimación de Kaplan-Meier , Hígado/patología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Masculino , Ratones , Persona de Mediana Edad , Invasividad Neoplásica/genética , Proteínas de Unión al ARN/genética , RNA-Seq , Transducción de Señal/genética , Factores de Transcripción/genética , Hipoxia Tumoral , Regulación hacia Arriba , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Appl Radiat Isot ; 168: 109465, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33218917

RESUMEN

Hydrothermal pretreatment of soils (Andosols) from Ibaraki prefecture (Japan) was used to improve methods for monitoring radioactive Sr and U. Calcined samples were pretreated with subcritical or supercritical water (SCW) followed by extraction with 0.5 M HNO3 solutions. With SCW pretreatment, recoveries of Sr and U were 70% and 40%, respectively. Experimental recoveries obtained can be described by a linear relationship in water density. The proposed method is robust and can lower environmental burden of routine analytical protocols.


Asunto(s)
Contaminantes Radiactivos del Suelo/análisis , Contaminantes Radiactivos del Agua/análisis , Monitoreo de Radiación/métodos , Radioisótopos de Estroncio/análisis , Uranio/análisis
20.
Nat Commun ; 10(1): 699, 2019 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-30741927

RESUMEN

Nitrogen-containing compounds, especially primary amines, are vital building blocks in nature and industry. Herein, a protocol is developed that shows in situ formed N-formyl quasi-catalytic species afford highly selective synthesis of formamides or amines with controllable levels from a variety of aldehyde- and ketone-derived platform chemical substrates under solvent-free conditions. Up to 99% yields of mono-substituted formamides are obtained in 3 min. The C-N bond formation and N-formyl species are prevalent in the cascade reaction sequence. Kinetic and isotope labeling experiments explicitly demonstrate that the C-N bond is activated for subsequent hydrogenation, in which formic acid acts as acid catalyst, hydrogen donor and as N-formyl species source that stabilize amine intermediates elucidated with density functional theory. The protocol provides access to imides from aldehydes, ketones, carboxylic acids, and mixed-substrates, requires no special catalysts, solvents or techniques and provides new avenues for amination chemistry.


Asunto(s)
Biomasa , Formamidas/química , Furaldehído/química , Cuasiespecies , Aldehídos , Aminación , Aminas , Catálisis , Formiatos , Hidrógeno , Hidrogenación , Imidas , Marcaje Isotópico , Cetonas , Cinética , Solventes
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