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1.
BMC Public Health ; 24(1): 1702, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926692

RESUMEN

Effects of short-term exposure to ambient air pollution on systemic immunological and inflammatory biomarkers in rural population have not been adequately characterized. From May to July 2021, 5816 participants in rural villages of northern Henan Province, China, participated in this cross-sectional study. Blood biomarkers of systemic inflammation were determined including peripheral white blood cells (WBC), eosinophils (EOS), basophils (BAS), monocytes (MON), lymphocytes (LYM), neutrophils (NEU), neutrophil-lymphocyte ratio (NLR), and serum high-sensitivity C-reactive protein (hs-CRP). The concentrations of ambient fine particulate matter (PM2.5), PM10, nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3) were assessed up to 7 days prior to the blood draw. A generalized linear model was used to analyze the associations between air pollution exposure and the above-mentioned blood biomarkers. Significantly positive associations were revealed between PM2.5, CO and WBC; CO, O3 and LYM; PM2.5, PM10, SO2, CO and NEU; PM2.5, PM10, SO2, CO and NLR; PM2.5, PM10, SO2, NO2, CO, O3 and hs-CRP. Meanwhile, negative associations were found between SO2 and WBC; PM2.5, PM10, NO2, CO, or O3 and EOS; PM2.5, SO2, or CO and BAS; SO2, NO2 or O3 and MON; PM2.5, PM10, SO2, or NO2 and LYM. Moreover, men, individuals with normal body mass index (BMI), current smokers, and those older than 60 years were found vulnerable to air pollution effects. Taken together, short-term exposure to air pollution was associated with systemic inflammatory responses, providing insight into the potential mechanisms for air pollution-induced detrimental systemic effects in rural residents.


Asunto(s)
Contaminación del Aire , Biomarcadores , Exposición a Riesgos Ambientales , Inflamación , Población Rural , Humanos , Estudios Transversales , Masculino , Femenino , Persona de Mediana Edad , Biomarcadores/sangre , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Población Rural/estadística & datos numéricos , China/epidemiología , Inflamación/sangre , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , Adulto , Material Particulado/efectos adversos , Material Particulado/análisis , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Leucocitos , Anciano , Proteína C-Reactiva/análisis , Recuento de Leucocitos
2.
Biomed Pharmacother ; 176: 116843, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38810405

RESUMEN

Hyperlipidemia-induced osteoporosis is marked by increased bone marrow adiposity, and treatment with statins for hyperlipidemia often leads to new-onset osteoporosis. Endosome-associated trafficking regulator 1 (ENTR1) has been found to interact with different proteins in pathophysiology, but its exact role in adipogenesis is not yet understood. This research aimed to explore the role of ENTR1 in adipogenesis and to discover a new small molecule that targets ENTR1 for evaluating its effectiveness in treating hyperlipidemia-induced osteoporosis. We found that ENTR1 expression increased during the adipogenesis of bone marrow mesenchymal cells (BMSCs). ENTR1 gain- and loss-of-function assays significantly enhanced lipid droplets formation. Mechanistically, ENTR1 binds peroxisome proliferator-activated receptor γ (PPARγ) and enhances its expression, thereby elevating adipogenic markers including C/EBPα and LDLR. Therapeutically, AN698/40746067 attenuated adipogenesis by targeting ENTR1 to suppress PPARγ. In vivo, AN698/40746067 reduced bone marrow adiposity and bone loss, as well as prevented lipogenesis-related obesity, inflammation, steatohepatitis, and abnormal serum lipid levels during hyperlipidemia. Together, these findings suggest that ENTR1 facilitates adipogenesis by PPARγ involved in BMSCs' differentiation, and targeted inhibition of ENTR1 by AN698/40746067 may offer a promising therapy for addressing lipogenesis-related challenges and alleviating osteoporosis following hyperlipidemia.


Asunto(s)
Adipogénesis , Adiposidad , Médula Ósea , Hiperlipidemias , Células Madre Mesenquimatosas , Ratones Endogámicos C57BL , Osteoporosis , PPAR gamma , Animales , Hiperlipidemias/tratamiento farmacológico , Hiperlipidemias/metabolismo , Osteoporosis/tratamiento farmacológico , Osteoporosis/metabolismo , Osteoporosis/etiología , Osteoporosis/prevención & control , PPAR gamma/metabolismo , Adipogénesis/efectos de los fármacos , Adiposidad/efectos de los fármacos , Ratones , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Masculino , Médula Ósea/metabolismo , Médula Ósea/efectos de los fármacos , Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo
3.
Environ Pollut ; 345: 123435, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38295929

RESUMEN

Exposure to fine particulate matter (PM2.5) has been associated with impaired airway innate immunity, leading to diverse lung disorders. However, the mechanisms of the adverse effects of PM2.5 on the airway innate immune system has not been adequately elucidated. This study aimed to investigate the association between short-term exposure to ambient PM2.5 and airway innate immune responses. A panel study of 53 undergraduate students was conducted in November 2020 and April 2021. Levels of airway innate immune biomarkers including interleukin-1ß (IL-1ß), IL-4, IL-6, IL-8, IL-17, interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), myeloperoxidase (MPO), and matrix metalloproteinase-9 (MMP-9) in induced sputum were measured, and airway microbiota and metabolites examined. Linear mixed-effect model was used to evaluate the effects of short-term exposure to PM2.5 on the above-listed airway immune biomarkers. The results indicated that for every 10 µg/m3 increase in PM2.5 concentration (at lag3), was associated with an increase of 21.3 % (5.4 %-37.1 %), 26.2 % (0.30 %-52.1 %), 22.4 % (0.70 %-44.2 %), 27.4 % (6.6 %-48.3 %), 18.3 % (4.6 %-31.9 %), 3.9 % (0.20 %-7.6 %) or 2.4 % (0.10 %-4.7 %) in IL-6, TNF-α, IL-17, IL-4, IFN-γ, MPO, or MMP-9 levels, respectively. Meanwhile, exposure to higher levels of ambient PM2.5 was found to significantly modulate airway microbiota and metabolite profile. Specifically, Prevotella and Fusobacterium, as well as 96 different metabolites were associated with PM2.5 levels. The metabolic pathways associated with these metabolites mainly included amino acid biosynthesis and metabolism. Notably, PM2.5 exposure-induced alterations of some airway microbiota were significantly correlated with specific airway metabolic change. Taken together, these results demonstrated that short-term exposure to PM2.5 was associated with alterations of airway immune response, microbial dysbiosis and changes of metabolites. This study provided insights into the mechanisms underlying PM2.5-induced airway innate immune responses.


Asunto(s)
Contaminantes Atmosféricos , Microbiota , Humanos , Interleucina-17 , Metaloproteinasa 9 de la Matriz , Factor de Necrosis Tumoral alfa/metabolismo , Interleucina-6 , Interleucina-4 , Material Particulado/toxicidad , Interferón gamma , Inmunidad Innata , Biomarcadores , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis
4.
J Periodontol ; 95(2): 146-158, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37436700

RESUMEN

BACKGROUND: Periodontal ligament-associated protein-1 (PLAP-1), an important target molecule of osteoarthritis research, may affect alveolar bone resorption. The aim of our study was to comprehensively and systematically detect the effect of PLAP-1 on alveolar bone resorption and the underlying mechanism in PLAP-1 knockout mouse models. METHODS: We used a PLAP-1 knockout (C57BL/6N-Plap-1-/- ) mouse model to investigate the effect of PLAP-1 on osteoclast differentiation and the underlying mechanism by adding Porphyromonas gingivalis lipopolysaccharide to stimulate bone marrow-derived macrophages. The effect of PLAP-1 on alveolar bone resorption and the underlying mechanism were studied using a ligature periodontitis model, with microcomputed tomography imaging, immunochemistry, and immunofluorescence. RESULTS: The in vitro analysis results demonstrated that PLAP-1 knockout significantly inhibited osteoclast differentiation under both normal and inflammatory conditions. Bioinformatic analysis, immunofluorescence, and co-immunoprecipitation showed colocalization and interaction between PLAP-1 and transforming growth factor beta 1 (TGF-ß1). The phosphorylation of Smad1 was reduced in the PLAP-1 knockout cells compared with that in the cells from wild-type mice. The in vivo analysis results demonstrated that PLAP-1 knockout decreased bone resorption and the levels of osteoclast differentiation markers in experimental periodontitis compared with those in wild-type mice. Immunofluorescence staining confirmed colocalization of PLAP-1 and TGF-ß1 in the experimental periodontitis model. The phosphorylation level of Smad1 was significantly reduced in PLAP-1 knockout mice compared with that in wild-type mice. CONCLUSIONS: This study revealed that the knockout of PLAP-1 inhibits osteoclast differentiation and decreases alveolar bone resorption through the TGF-ß1/Smad1 signaling pathway, which could serve as an innovative target for the prevention and treatment of periodontitis.


Asunto(s)
Pérdida de Hueso Alveolar , Periodontitis , Animales , Ratones , Ratones Endogámicos C57BL , Osteogénesis , Ligamento Periodontal , Proteína Smad1 , Factor de Crecimiento Transformador beta1 , Microtomografía por Rayos X
5.
Small ; 20(22): e2309181, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38100297

RESUMEN

The development of catalysts with abundant active interfaces for superior low-temperature catalytic CO oxidation is critical to meet increasingly rigorous emission requirements, yet still challenging. Herein, this work reports a PtCo/CoOx/Al2O3 catalyst with PtCo clusters and enriched Pt─O─Co interfaces induced by hydrogen spillover from the Pt sites and self-oxidation process in air, exhibiting excellent performance for CO oxidation at low temperatures and humid conditions. The combination of structural characterizations and in situ Fourier transform infrared spectroscopy reveals that the PtCo cluster effectively prevents CO saturation/poisoning on the Pt surface. Additionally, the presence of Pt─O─Co interfaces in the PtCo/CoOx/Al2O3 catalyst provides a significant number of active sites for oxygen activation and ─OH formation. This facilitates efficient generation of CO2 at ambient temperature by coupling with nearby adsorbed CO molecules, resulting in superior low-temperature activity and long-term stability for CO oxidation under humid conditions. This work provides a facile route toward rationalizing the design of catalysts with more active interfaces for superior low-temperature CO oxidation under humid conditions for practical applications.

6.
Pestic Biochem Physiol ; 194: 105503, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37532323

RESUMEN

Glyphodes pyloalis Walker (G. pyloalis) is a common destructive mulberry pest. Due to the long-term and frequent use of insecticides, it has developed tolerance to commonly used insecticides. Tolfenpyrad (TFP) is a novel pyrazole heterocyclic insecticide. In order to understand the TFP detoxification mechanism of G. pyloalis larvae, we first estimated the LC30 dose of TFP for 3rd instar G. pyloalis larvae. Next, we identified genes that were differentially expressed in 3rd instar G. pyloalis larvae treated with TFP compared to the control group by transcriptome sequencing. In total, 86,949,569 and 67,442,028 clean reads were obtained from TFP-treated and control G. pyloalis larvae, respectively. A total of 5588 differentially expressed genes (DEGs) were identified in TFP-treated and control G. pyloalis larvae, of which 3084 genes were upregulated and 2504 genes were downregulated. We analyzed the expression of 43 candidate detoxification enzyme genes associated with insecticide tolerance using qPCR. According to the spatiotemporal expression pattern of DEGs, we found that CYP6ABE1, CYP333A36 and GST-epsilon8 were highly expressed in the midgut, while CarEs14 was strongly expressed in haemolymph. Furthermore, we successfully knocked down these genes by RNA interference. After silencing CYP6ABE1 and CYP333A36, bioassay showed that the mortality rate of TFP-treated G. pyloalis larvae was significantly higher compared to the control group. This study provides a theoretical foundation for understanding the sensitivity of G. pyloalis to TFP and establish the basis for the effective and green management of this pest.


Asunto(s)
Insecticidas , Mariposas Nocturnas , Animales , Insecticidas/farmacología , Insecticidas/metabolismo , Mariposas Nocturnas/metabolismo , Larva/genética , Pirazoles/metabolismo
7.
J Hazard Mater ; 457: 131746, 2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37270959

RESUMEN

The development of new strategies to improve the removal of organic pollutants with permanganate (KMnO4) is a hot topic in water treatment. While Mn oxides have been extensively used in Advanced Oxidation Processes through an electron transfer mechanism, the field of KMnO4 activation remains relatively unexplored. Interestingly, this study has discovered that Mn oxides with high oxidation states including γ-MnOOH, α-Mn2O3 and α-MnO2, exhibited excellent performance to degrade phenols and antibiotics in the presence of KMnO4. The MnO4- species initially formed stable complexes with the surface Mn(III/IV) species and showed an increased oxidation potential and electron transfer reactivity, caused by the electron-withdrawing capacity of the Mn species acting as Lewis acids. Conversely, for MnO and γ-Mn3O4 with Mn(II) species, they reacted with KMnO4 to produce cMnO2 with very low activity for phenol degradation. The direct electron transfer mechanism in α-MnO2/KMnO4 system was further confirmed through the inhibiting effect of acetonitrile and the galvanic oxidation process. Moreover, the adaptability and reusability of α-MnO2 in complicated waters indicated its potential for application in water treatment. Overall, the findings shed light on the development of Mn-based catalysts for organic pollutants degradation via KMnO4 activation and understanding of the surface-promoted mechanism.

8.
ACS Appl Mater Interfaces ; 15(18): 22075-22084, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37116203

RESUMEN

Fenton iron mud (IM) is a hazardous solid waste produced by Fenton oxidation technology after treating industrial wastewater. Thus, it is necessary and challenging to develop a recycling technology to back-convert dangerous materials into useful products. Herein, we develop a sustainable approach to prepare highly active metal oxides via a solid-state grinding method. IM, as an amorphous material, can disperse and interact well with these supported metal oxides, boosting toluene degradation significantly. Among these IM-based catalysts, the catalyst 8% MnOx/IM-0.2VC exhibits the best performance (T100 = 290 °C), originating from the oxide-support interaction and optimal balance between low-temperature reducibility and oxygen vacancy concentration. In addition, in situ diffuse reflectance infrared Fourier transform spectrometry (DRIFTS) results expound that ring breakage is prone to occur on MnOx, and oxygen vacancies are beneficial to adsorb oxygen and activate oxygen species to boost toluene oxidation following the Mars-van Krevelen mechanism. This work advances a complete industrial hazardous waste recycling route to develop extremely active catalysts.

9.
J Hazard Mater ; 443(Pt A): 130178, 2023 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-36252404

RESUMEN

The development of efficient and eco-friendly Mn-based hybrids for the degradation of biorefractory organic pollutants via peroxymonosulfate (PMS) activation is highly desired. In this study, a novel graphite nanosheet (GNs)-based Fe-Mn bimetallic oxide (Fe doped birnessite MnO2, FeMn/GNs) was synthesized under mild conditions. Compared with monometallic Fe or Mn oxide on GNs, FeMn/GNs exhibited a higher surface area, decreased Mn oxidation states, stronger interaction with GNs, and more active sites for PMS adsorption. Among different Fe/Mn ratios, Fe2Mn1/GNs showed the optimum performance for bisphenol A (BPA) degradation with the first-order rate constant of 0.22 min-1, which was about 8.5 and 12.9 times higher than that of Mn/GNs and Fe/GNs, respectively. Different from the pollutant-catalyst-PMS electron transfer mechanism for Mn/GNs, the direct two-electron transfer in FeMn/GNs+PMS system, was mainly processed between the simultaneously activated BPA and PMS. This was probably based on the double adsorption sites of Fe and Mn species on the same catalyst: PMS was adsorbed by Fe species through hydroxyl groups, while BPA was mainly coordinated with Mn species due to the layered structure and hydrophobicity of the Mn oxide. This study is expected to provide the rational design of efficient Mn-based hybrids for PMS activation.


Asunto(s)
Contaminantes Ambientales , Grafito , Óxidos , Contaminantes Ambientales/química , Compuestos de Manganeso , Electrones , Peróxidos/química , Grafito/química , Compuestos Orgánicos
10.
J Hazard Mater ; 433: 128765, 2022 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-35390616

RESUMEN

Quenching is a powerful method for modulating surface structures of metal oxide nanocatalysts to achieve high catalytic oxidation activities, but it is still challenging. Herein, a catalyst of ultrafine Co3O4 nanoparticles decorated on Co-doped LaMnO3 (Co3O4/LaCoxMn1-xO3) is synthesized via one-step quenching perovskite-type LaMnO3 nanocatalyst into an aqueous solution of cobalt nitrate, which exhibits significantly improved catalytic performance with toluene (1000 ppm) conversion of 90% at 269 °C under the gas hourly space velocity of 72000 mL g-1 h-1. The high catalytic activity correlates with large surface area, abundant oxygen vacancies and good reducibility. Furthermore, density functional theory calculations disclose that Co doping and interfacial effect of Co3O4/LaCoxMn1-xO3 can achieve lower C-H bond activation energy. These findings provide a unique and effective route towards surface modification of nanocatalysts.

11.
Plant Physiol ; 189(2): 1037-1049, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35238391

RESUMEN

The regulatory mechanisms that link WRKY gene expression to fruit ripening are largely unknown. Using transgenic approaches, we showed that a WRKY gene from wild strawberry (Fragaria vesca), FvWRKY48, may be involved in fruit softening and ripening. We showed that FvWRKY48 is localized to the nucleus and that degradation of the pectin cell wall polymer homogalacturonan, which is present in the middle lamella and tricellular junction zones of the fruit, was greater in FvWRKY48-OE (overexpressing) fruits than in empty vector (EV)-transformed fruits and less substantial in FvWRKY48-RNAi (RNA interference) fruits. Transcriptomic analysis indicated that the expression of pectate lyase A (FvPLA) was significantly downregulated in the FvWRKY48-RNAi receptacle. We determined that FvWRKY48 bound to the FvPLA promoter via a W-box element through yeast one-hybrid, electrophoretic mobility shift, and chromatin immunoprecipitation quantitative polymerase chain reaction experiments, and ß-glucosidase activity assays suggested that this binding promotes pectate lyase activity. In addition, softening and pectin degradation were more intense in FvPLA-OE fruit than in EV fruit, and the middle lamella and tricellular junction zones were denser in FvPLA-RNAi fruit than in EV fruit. We speculated that FvWRKY48 maybe increase the expression of FvPLA, resulting in pectin degradation and fruit softening.


Asunto(s)
Fragaria , Pared Celular/genética , Pared Celular/metabolismo , Fragaria/genética , Fragaria/metabolismo , Frutas/genética , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas , Pectinas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Polisacárido Liasas
12.
ACS Appl Mater Interfaces ; 13(41): 48764-48773, 2021 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34633806

RESUMEN

A catalyst with high-entropy oxide (HEO)-stabilized single-atom Pt can afford low-temperature activity for catalytic oxidation and remarkable durability even under harsh conditions. However, HEO is easy to harden during sintering, which results in a few defective sites for anchoring single-atom metals. Herein, we present a sol-gel-assisted mechanical milling strategy to achieve a single-atom catalyst of Pt-HEO/Al2O3. The strong interaction between HEO and Al2O3 effectively inhibits the growth of HEO microparticles, which leads to generation of more surface defects because of the nanoscale effect. Meanwhile, another strong interaction between Pt and HEO stabilizes single-atom Pt on HEO. Temperature-programmed techniques further verify that the reactivity of surface lattice oxygen species is enhanced because of the Pt-O-M bonds on the surface of HEO. Unlike conventional single-atom Pt catalysts, Pt-HEO/Al2O3 as a heterogeneous catalyst not only exhibits superior stability against hydrothermal aging but also presents long-term reaction stability for CO catalytic oxidation, which exceeds 540 h. The present work opens a new door for rational design of hydrothermally stable single-atom Pt catalysts, which are highly promising in practical applications.

13.
ACS Appl Mater Interfaces ; 12(45): 50566-50572, 2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-33125220

RESUMEN

Manganese oxides have displayed vast potential for future development in the field of catalytic abatement of volatile organic compounds (VOCs) because of their low cost, high stability, and enhanced catalytic activity. Manganese sulfate and manganese chloride are widely used as reaction sources to prepare manganese oxides. As reported, absorbed chloride usually affects the performance of catalysts. However, the effect of absorbed sulfate on catalysts has been overlooked at present. Herein, the poisoning effect of absorbed sulfate on MnO2 catalyst in the catalytic oxidation of VOCs has been uncovered. Manganese sulfate-derived MnO2 catalyst exhibits a significantly enhanced performance after repeated washing by water, which indicates that absorbed sulfate has an adverse effect on MnO2 catalyst for removal of VOCs. The blocking of the surface oxygen species and active sites is considered as the reason for sulfate poisoning. Hence, elimination of absorbed sulfate by thorough washing or other effective method is essential for preparing high-performance manganese sulfate-derived manganese oxide catalysts.

14.
Plant Physiol Biochem ; 154: 54-65, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32526611

RESUMEN

Although fruit expansion during ripening has been extensively studied, the structural and metabolic mechanisms remain largely unknown. Here, we report the critical roles of cell separation and cell wall metabolism in the coordinated regulation of fruit expansion in Fragaria vesca. Anatomical observations indicated that a syndrome of cell separation occurred from the very earliest stage of fruit set. Cell separation led to an increase in apoplastic space, and the time course of this increase coincided with the period of fruit development and ripening. Moreover, massive cellulose disassembly occurred when cells were fully separated, which coincided with the expansion of cell and fruit volume. Consistent with the anatomical observations, both histochemistry and composition analysis indicated correlations between cell separation and the cell wall metabolism. These observations suggest that cell separation, cell elongation and cell wall disassembly occur simultaneously during fruit ripening in Fragaria vesca.


Asunto(s)
Pared Celular/fisiología , Fragaria/fisiología , Frutas/fisiología
15.
Zhongguo Yi Liao Qi Xie Za Zhi ; 42(5): 365-367, 2018 Sep 30.
Artículo en Chino | MEDLINE | ID: mdl-30358353

RESUMEN

OBJECTIVE: To investigate the feasibility of using liquid chromatography (HPLC) to characterize the 3, 4-Dihydroxyphenylalanine (DOPA) redox state of mussel adhesive protein (MAP). METHODS: The DOPA and protein contents of MAP were determined by HPLC, Arnow and Bradford methods respectively. RESULTS: With extended oxidation time, the protein contents of MAP samples remained unchanged whereas the DOPA contents declined. The retention times of main peaks in HPLC for both the accelerated oxidation and retained samples shifted as the storage time extended, which could be related to the changes of sample redox state. CONCLUSIONS: The redox state of MAP can be characterized by the change of HPLC peak retention time. HPLC can be used in the research on the MAP redox state, which is beneficial to the product development and quality control.


Asunto(s)
Cromatografía Liquida , Dihidroxifenilalanina , Proteínas , Dihidroxifenilalanina/química , Oxidación-Reducción
16.
Nanomaterials (Basel) ; 8(4)2018 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-29673172

RESUMEN

Using a microwave-assisted ball-milling approach, Fe-based metal-organic frameworks (Fe-MOFs) were prepared from FeSO4·7H2O and trimesic acid. Scanning electron microscopy, Fourier-transform infrared spectrometry, X-ray, and thermogravimetric analysis were utilized to characterize the thermal stability and structure of the prepared Fe-MOFs. These Fe-MOFs were used to remove organic dyes from aqueous solutions. Specifically, they removed 96.97% of 23.3592 mg/L of Congo red in a 200 mL solution within 300 min of treatment with natural light at 15 °C. Likewise, 88.21 and 70.90% of 22.7527 mg/L of Orange II and 17.8326 mg/L of Rhodamine B, respectively, were removed from 200 mL solutions within 300 min of treatment at 15 °C. At 35 °C, 99.57, 95.98, and 99.38% of 23.3855 mg/L of Congo Red, 22.7365 mg/L of Orange II, and 17.9973 mg/L of Rhodamine B, respectively, were removed from 200 mL solutions within 300 min of treatment. The adsorption kinetics were investigated and the pseudo-first-order kinetic model was found to be superior to the pseudo-second-order kinetic model. Overall, using metal-organic frameworks to treat dye wastewater was found to be inexpensive, feasible, and efficient. Therefore, this material has future prospects in research and applications in the purification of wastewater.

17.
Dalton Trans ; 46(47): 16525-16531, 2017 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-29152624

RESUMEN

Fe-Based metal-organic frameworks (Fe-MOFs) were prepared with trimesic acid and FeSO4·7H2O via a microwave-assisted ball milling approach. The structure and thermal stability of the as-prepared Fe-MOFs were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FTIR), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). When used to degrade 20 mg L-1 hexavalent chromium in aqueous solution, the Fe-MOFs were found to completely reduce a 100 mL solution within 120 min under natural light and a 400 mL solution within 90 min under Xe lamp irradiation. Under natural sunlight, 98% of the Cr(vi) was removed from a 40 mL solution after 40 min.

18.
Anal Chem ; 89(17): 9062-9068, 2017 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-28786659

RESUMEN

Presented herein is a simple, robust, and label-free homogeneous electrochemical sensing platform constructed for the detection of protein kinase activity and inhibition by integration of carboxypeptidase Y (CPY)-assisted peptide cleavage reaction and vertically ordered mesoporous silica films (MSFs). In this sensing platform, the substrate peptide composed of kinase-specific recognized sequence and multiple positively charged arginine (R) residues was ingeniously designed. In the presence of protein kinase, the substrate peptide was phosphorylated and then immediately resisted CPY cleavage. The phosphorylated peptide could be effectively adsorbed on the negatively charged surface of MSFs modified indium-tin oxide (ITO) electrode (MSFs/ITO) by noncovalent electrostatic attraction. The adsorbed peptide was subsequently used as a hamper to prevent the diffusion of electroactive probe (FcMeOH) to the electrode surface through the vertically aligned nanopores, resulting in a detectable reduction of electrochemical signal. As demonstrated for the feasibility and universality of the sensing platform, both protein kinase A (PKA) and casein kinase II (CK2) were selected as the models, and the detection limits were determined to be 0.083 and 0.095 UmL-1, respectively. This sensing platform had the merits of simplicity, easy manipulation, and improved phosphorylation and cleavage efficiency, which benefited from homogeneous solution reactions without sophisticated modification or immobilization procedures. In addition, given the key role of inhibition and protein kinase activity detection in cell lysates, this proposed sensing platform showed great potential in kinase-related bioanalysis and clinical biomedicine.


Asunto(s)
Catepsina A/metabolismo , Técnicas Electroquímicas/métodos , Proteínas Quinasas/metabolismo , Dióxido de Silicio/química , Catepsina A/química , Células HeLa , Humanos , Membranas Artificiales , Inhibidores de Proteínas Quinasas , Proteínas Quinasas/química
19.
Ultrason Sonochem ; 39: 845-852, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28733014

RESUMEN

Metal-organic frameworks (MOFs) were successfully synthesized by ultrasonic wave-assisted ball milling. In the absence of organic solvent, the coupling effect of ultrasonic wave and mechanical force played an significant role in the synthesis of MOFs. Adsorption of Congo red (CR) was studied in view of adsorption kinetic, isotherm and thermodynamics. The adsorbent was carried out using X-ray diffraction (XRD), thermogravimetric analysis (TGA), N2 adsorption-desorption isotherms, Raman spectroscopy and scanning electron microscope (SEM) methods. It was found that pseudo-second-order kinetic model and Freundlich adsorption isotherm matched well for the adsorption of CR onto nickel-based metal-organic framework/graphene oxide composites (Ni-MOF/GO). The results of the adsorption thermodynamics indicated that the adsorption process was a spontaneous and endothermic process. The adsorption capacity of graphene oxide/metal-organic frameworks (GO/MOFs) for CR reached 2489mg/g, much higher than previous reports. It was demonstrated that an increase in the number of active metal sites can dramatically improve the adsorption capacity of dye. A suitable dry temperature is beneficial for the improvement of adsorption capacity for dye. In this paper, the adsorption results indicated that ultrasonic wave-assisted ball milling has a good prospect for synthesis of MOFs with excellent adsorption performance.

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