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1.
Isr Med Assoc J ; 22(1): 32-36, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31927803

RESUMEN

BACKGROUND: Evaluation of mismatch repair (MMR) deficiency is conducted via immunohistochemistry or by microsatellite instability (MSI) analysis. Heterogeneous immunohistochemistry staining for MMR proteins may show different patterns; however, according to current guidelines, all of those patterns should be interpreted as MMR proficient. This conclusion might lead to false negative results because although most cases of heterogeneity stem from technical factors and biological variability, other types of heterogeneity represent true MMR deficiency. OBJECTIVES: To identify a unique heterogeneity pattern that is associated with true MMR loss. METHODS: We analyzed 145 cases of colorectal carcinoma. Immunohistochemistry staining for MLH1, PMS2, MSH2, and MSH6 were performed. We defined geographic heterogeneity as areas of tumor nuclear staining adjacent to areas of loss of tumor nuclear staining with intact staining in the surrounding stroma. All cases were evaluated for the presence of geographic heterogeneity. In addition, 24 cases were also evaluated by MSI testing. RESULTS: Of the 145 cases, 24 (16.5%) were MMR deficient. Of the 24 cases for which MSI analysis was also available, 10 cases (41.7%) demonstrated biological heterogeneity, 5 (20.8%) demonstrated technical heterogeneity, and 2 (8.3%) demonstrated geographic heterogeneity. Only the two cases with geographic heterogeneity were MSI-high via MSI analysis. In addition, a germline mutation in MSH-6 was identified in one of these cases. CONCLUSIONS: Geographic heterogeneity may raise a suspicion for a MMR-deficient case, which should be further analyzed using additional methodologies such as MSI analysis.


Asunto(s)
Reparación de la Incompatibilidad de ADN/genética , Proteínas MutS/genética , Adenoma/genética , Adenoma/patología , Adulto , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Colorantes , Heterogeneidad Genética , Humanos , Masculino
2.
Bioresour Technol ; 301: 122721, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31986372

RESUMEN

The main aim of this work is focused towards possible reuse of both solid and liquid waste generated from the natural indigo dye production process. The solid waste (C/N:15.01) was utilized to produce stable compost with possible re-use in Indigofera cultivation. Among seven compost combinations (C1-C7) using jeevamrutha (JA) and cow-dung (CD) as inoculum, C4 with 8% JA showed higher biomass degradation (51%) and plant growth potential (GI > 125%). Whereas the undiluted liquid waste was treated using algal consortia, bacteria, and indigenous microbial population, achieved a maximum removal of 90% ammonia, 82% nitrate, and 88% phosphorus for its re-use in the dye production process. Hence, incorporation of suitable waste management strategies in natural indigo dye production could help to achieve a zero waste sustainable process.


Asunto(s)
Indigofera , Administración de Residuos , Animales , Biomasa , Bovinos , Colorantes , Femenino , Carmin de Índigo , Residuos Sólidos
3.
J Environ Manage ; 258: 110012, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31929054

RESUMEN

Manganese-Aluminum powders were recently reported to show high efficiency and fast reaction rates as decolorization materials for azo-dye aqueous solutions. This work presents a detailed study of different aspects of this material. Firstly, the influence of the crystalline phase and the microstructure was studied by comparing the efficiency of powders obtained by different production protocols. Secondly, the decolorization efficiency was investigated on various types of dyes, including real textile wastewater samples. The analysis of the treated water and the particles showed that the main reaction mechanism was the breaking of the azo-dye molecules, although important adsorption on the metallic surface was observed for some colorants. Finally, the reusability of the particles and the reduction of toxicity achieved during the treatments were assessed. The simple production and application methods, the high efficiency and the use of environmentally friendly metallic elements are the main advantages of Manganese-Aluminum powders compared to other high-efficient decolorizing metallic materials.


Asunto(s)
Contaminantes Químicos del Agua , Compuestos Azo , Colorantes , Polvos , Aguas Residuales
4.
J Environ Manage ; 258: 110050, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31929077

RESUMEN

Photocatalytic degradation is among the promising technology for removal of various dyes and organic contaminants from environment owing to its excellent catalytic activity, low energy utilization, and low cost. As one of potential photocatalysts, Fe2O3 has emerged as an important material for degradation of numerous dyes and organic contaminants caused by its tolerable band gap, wide harvesting of visible light, good stability and recyclability. The present review thoroughly summarized the classification, synthesis route of Fe2O3 with different morphologies, and several modifications of Fe2O3 for improved photocatalytic performance. These include the incorporation with supporting materials, formation of heterojunction with other semiconductor photocatalysts, as well as the fabrication of Z-scheme. Explicitly, the other photocatalytic applications of Fe2O3, including for removal of heavy metals, reduction of CO2, evolution of H2, and N2 fixation are also deliberately discussed to further highlight the huge potential of this catalyst. Moreover, the prospects and future challenges are also comprised to expose the unscrutinized criteria of Fe2O3 photocatalyst. This review aims to contribute a knowledge transfer for providing more information on the potential of Fe2O3 photocatalyst. In the meantime, it might give an idea for utilization of this photocatalyst in other environmental remediation application.


Asunto(s)
Colorantes , Luz , Catálisis , Semiconductores
5.
Khirurgiia (Mosk) ; (1): 61-66, 2020.
Artículo en Ruso | MEDLINE | ID: mdl-31994501

RESUMEN

OBJECTIVE: To develop a method for analysis of lymphatic drainage pathways from the lobe of the lung affected by non-small cell lung cancer (NSCLC) using infrared fluorescence. MATERIAL AND METHODS: A study enrolled patients with NSCLC who underwent anatomic resection of the lung with systematic lymph node dissection and preliminary intraoperative peritumoral injection of indocyanine green conjugate with human albumin. Registration of fluorescence in regional lymph nodes (LN) was carried out immediately after excision of specimen using the FLUM-808 instrumental system. RESULTS: Infrared fluorescence was observed in 117 hilar and mediastinal lymph nodes from 43 patients (2.7 nodes per a patient). Comparison of localization of fluorescent LN with localization of tumor in various lobes established significant variability of lymphatic drainage pathways. CONCLUSION: The developed method of infrared fluorescent evaluation of lymphatic drainage in patients with NSCLC confirms the necessity of systematic lymph node dissection for adequate staging.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/patología , Metástasis Linfática/diagnóstico por imagen , Estadificación de Neoplasias/métodos , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/fisiopatología , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Colorantes , Fluorescencia , Humanos , Verde de Indocianina , Rayos Infrarrojos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/fisiopatología , Neoplasias Pulmonares/cirugía , Escisión del Ganglio Linfático , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/fisiopatología , Ganglios Linfáticos/cirugía , Metástasis Linfática/fisiopatología
6.
Medicine (Baltimore) ; 99(2): e18467, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31914018

RESUMEN

BACKGROUND: Curcumin, a controversial "panacea," has been broadly studied. Its bioactivities including antioxidant, anti-inflammatory, and especially antineoplastic activities have been documented. However, due to its extensive bioactivities, some scientists hold a skeptical point of view toward curcumin and described curcumin as a "deceiver" to chemists. The objective of this study was to explore curcumin's another possibility as a potential supplementary leading compound to cancer treatments. METHODS: Literature searches were conducted using electronic databases. Search terms such as "curcumin," "curcumin analogues," and so on were used. The literatures were collected and summarized. In this article, reported targets of curcumin are reviewed. The limitations of a curcumin as a therapeutic anticancer product including low bioavailability and poor targeting are mentioned. Furthermore, modified curcumin analogues and antitumor mechanisms are listed and discussed in the aspects of cell death and tumor microenvironment including angiogenesis, tissue hypoxia status, and energy metabolism. RESULTS: Several possible modification strategies were presented by analyzing the relationships between the antitumor activity of curcumin analogues and their structural characteristics, including the introduction of hydrophilic group, shortening of redundant hydrocarbon chain, the introduction of extra chemical group, and so on. CONCLUSIONS: From our perspective, after structural modification curcumin could be more effective complementary product for cancer therapies by the enhancement of targeting abilities and the improvement of bioavailability.


Asunto(s)
Colorantes/metabolismo , Colorantes/farmacología , Curcumina/metabolismo , Curcumina/farmacología , Antineoplásicos , Disponibilidad Biológica , Muerte Celular/efectos de los fármacos , Terapias Complementarias , Curcumina/química , Humanos , Neoplasias/tratamiento farmacológico , Microambiente Tumoral/efectos de los fármacos
7.
J Photochem Photobiol B ; 202: 111682, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31731077

RESUMEN

Development of highly robust and solar-light-responsive photocatalysts for the disposal of organic dyes from wastewater is a matter of great significance in order to solve the problems of water pollution. Solar-driven photocatalytic degradation of dyes is considered as a quite efficient, sustainable and cost-effective approach as it involved the inexhaustible and renewable source of energy. In photocatalytic processes, the generation of electron-hole pairs at the surface of the photocatalyst is accomplished by harvesting solar energy. The electron-hole pairs are converted into •OH radicals that are responsible for the degradation of dyes. Herein, we reported the synthesis of nanosized iron (FeNPs) using the aqueous fruit extract of Actinidia chinensis as a reducing as well as the stabilizing agent. The structure and morphology of synthesized nanoparticles were characterized using various advanced techniques. The TEM micrographs showed that the synthesized FeNPs was predominantly cubic and rod-shaped having the size in the range of 91.78-107 nm. The as-prepared FeNPs were acted as effective photocatalysts and their photocatalytic activity evaluated against alizarin yellow R (AYR) dye. The effect of different reaction conditions such as temperature, pH, time and catalyst loading on photocatalytic degradation of AYR dye was investigated under sunlight irradiation. The FeNPs showed promising photocatalytic activity and up to 93.7% of the dye was degraded in 42 h. The kinetics parameter of the reaction was also evaluated which showed that the photocatalytic degradation of AYR dye followed the pseudo-first-order reaction. In terms of better degradation, the role of FeNPs might be extended for the treatment of different organic dyes from wastewater.


Asunto(s)
Compuestos Azo/química , Hierro/química , Nanopartículas del Metal/química , Aguas Residuales/química , Actinidia/química , Actinidia/metabolismo , Catálisis , Colorantes/química , Frutas/química , Frutas/metabolismo , Tecnología Química Verde , Concentración de Iones de Hidrógeno , Fotólisis/efectos de la radiación , Extractos Vegetales/química , Luz Solar , Temperatura Ambiental , Factores de Tiempo , Contaminantes Químicos del Agua/química
8.
Chemosphere ; 238: 124538, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31454745

RESUMEN

Although banned, dyes, such as Victoria pure blue BO (VPBO), are illicitly used in aquaculture to treat or prevent infections due to their therapeutic activities. The present study examined the formation of phase I and phase II metabolites derived from VPBO using trout liver microsomes and S9 proteins. The well-known malachite green (MG) dye was also studied as a positive control and to compare its metabolism with that of VPBO. First, we optimised the incubation conditions for the detection of VPBO and MG metabolites by studying the formation of cytochrome P450 (CYP) substrates. Using the determined conditions (2 h at 20 °C), we incubated VPBO with trout microsomal and S9 fractions induced with ß-naphtoflavone, and analysed the supernatant in a LC-LTQ-Orbitrap-HRMS system. The in vitro assays led to the detection of 16 VPBO metabolites from Phase I reactions, arising in particular from reactions with CYP1A. No metabolites were detected from Phase II reactions. The main metabolite detected, deethyl-VPBO, was CID-fragmented to determine its chemical structure, and thus recommend a potential biomarker for the control of VPBO in farmed fish foodstuffs.


Asunto(s)
Colorantes/metabolismo , Peces/metabolismo , Contaminación de Alimentos/análisis , Compuestos de Amonio Cuaternario/metabolismo , Alimentos Marinos , Animales , Acuicultura , Sistema Enzimático del Citocromo P-450/metabolismo , Metabolómica , Microsomas Hepáticos/metabolismo
9.
Chemosphere ; 238: 124539, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31470310

RESUMEN

The performance and microbial community structure of anaerobic dynamic membrane bioreactor (AnDMBR) treating textile wastewater was investigated. The reactor showed excellent soluble COD and color removal of 98.5% and >97.5%, respectively. Dynamic membrane layer grown over the 3D printed dynamic membrane support showed decent rejection for high molecular weight compounds (>20 kDa); and the total suspended solid rejection by the dynamic layer was >98.8%. Gel permeation chromatography analysis of extracellular polymeric substance (EPS) and effluent samples revealed EPS accounted for more than 76.7% of low molecular weight fractions (<20 kDa) that end up in the effluent. Higher applied flux facilitated the rapid formation dynamic layer which enabled a satisfactory effluent quality. Microbial community analysis revealed that during the operation the archaeal community was relatively stable while obvious changes took place in the bacterial community. Introduction of dye Remazol Brilliant Blue R (RBBR) to the AnDMBR increased the abundances of phyla of Proteobacteria and Spirochaetae whereas fractions of Firmicutes and Euryarchaeota decreased obviously. Furthermore, relative stable abundances of phyla Aminicenantes, Bacteroidetes, Thermotogae and Chloroflexi among the top six phyla detected in the system ensured a healthy anaerobic degradation environment for RBBR wastewater treatment.


Asunto(s)
Antraquinonas/aislamiento & purificación , Antraquinonas/metabolismo , Reactores Biológicos/microbiología , Membranas Artificiales , Textiles , Aguas Residuales/química , Anaerobiosis , Colorantes/aislamiento & purificación , Colorantes/metabolismo , Matriz Extracelular de Sustancias Poliméricas/microbiología , Proteobacteria/metabolismo , Spirochaeta/metabolismo , Contaminantes Químicos del Agua/aislamiento & purificación , Contaminantes Químicos del Agua/metabolismo
10.
Environ Technol ; 41(1): 71-85, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29923786

RESUMEN

In the present study, locally isolated Rhodococcus strains were attempted as biological tools for methyl red removal, a mutagenic azo dye posing threat to the environment if left untreated. Rhodococcus strain UCC 0016 demonstrated superior methyl red-decolourizing activity of 100% after 24 h at static condition in comparison to Rhodococcus strain UCC 0008 which recorded 65% decolourization after 72 h. Optimization of physicochemical parameters at 30°C, pH 7 and supplementing glucose as the carbon source resulted in improved methyl red-decolourizing activity at static condition and reduced the time taken to achieve complete decolourization by 80%. Higher concentration of methyl red (5 g/L) was able to be decolourized completely within 10 h by adopting the technology of immobilization. The encapsulated cells of Rhodococcus strain UCC 0016 demonstrated higher substrate affinity (Km = 0.6995 g/L) and an accelerated rate of disappearance of methyl red (Vmax = 0.3203 g/L/h) compared to the free cells. Furthermore, the gellan gum beads could be reused up to nine batches without substantial loss in the catalytic activity indicating the economic importance of this protocol. Analysis of methyl red degradation products revealed no germination inhibition on Triticum aestivum and Vigna radiata demonstrating complete toxicity removal of the parent dye after biological treatment. The occurrence of new and altered peaks (UV-Vis and FTIR) further supported the notion that the removal of methyl red by Rhodococcus strain UCC 0016 was indeed through biodegradation. Therefore, this strain has a huge potential as a candidate for efficient bioremediation of wastewater containing methyl red.


Asunto(s)
Rhodococcus , Esguinces y Distensiones , Compuestos Azo , Biodegradación Ambiental , Colorantes , Humanos
11.
Environ Technol ; 41(2): 238-250, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29985103

RESUMEN

In the present study, the decolourization efficiencies of LP-Hg lamp, XeCl and KrCl excilamps at the same power density were compared for the decolourization of dyes in water by UV and UV/H2O2 processes in a batch reactor. Laboratory prototypes of XeCl and KrCl excilamps and a commercial LP-Hg lamp were studied as UV sources. Methylene Blue and Eliamine Blue dyes were used as model pollutants. The effect of the initial concentrations of dye and H2O2 in the TOC removal and kinetic parameters were also studied. The ratio of dye decolourization to the electric power consumption of the KrCl excilamp and LP-Hg lamp for the decolourization of Methylene Blue and Eliamine Blue were evaluated. As a result, the KrCl excilamp showed significantly higher decolourization efficiencies than LP-Hg lamp and XeCl excilamp, but the dye removal rate was significantly slower for Methylene Blue than for Eliamine Blue with this lamp. The KrCl lamp can be an alternative to conventional LP-Hg lamp for the decolourization of dyes by photodegradation, but it depends on the type of dye treated. The addition of H2O2 in a concentration between 0.05 and 0.09%v/v increases significantly the efficiency of the decolourization of Methylene Blue, and further increase does not lead to a higher increase in conversion. The experimental data were fitted to the one phase decay kinetic model with good agreement and the kinetic parameters were reported.


Asunto(s)
Mercurio , Contaminantes Químicos del Agua , Colorantes , Peróxido de Hidrógeno , Rayos Ultravioleta , Agua
12.
J Environ Manage ; 254: 109784, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31726281

RESUMEN

A new water-insoluble bi-metallic coordination polymer was simply prepared via polymerization-precipitation of molybdenum complex building blocks with Zn2+ cation. The linker was a di-carboxylic acid consisting of two coordination sites i.e. N,O and COO- suitable for coordinating to MoO2 unit and Zn2+, respectively. Characterization of the prepared coordination polymer was carried out with various physicochemical methods which confirmed the proposed structure. The prepared coordination polymer preferentially adsorbed methylene blue (more than 92% of methylene blue after 2 min) relative to methyl orange and can be reused at least four times without any loss of adsorption efficiency. The adsorption process of both dyes followed the pseudo-second order kinetic equation. Additionally, the obtained coordination polymer catalyzed epoxidation of olefins with tert-butylhydroperoxide (TBHP) quantitatively with excellent selectivity (>99%) under mild reaction conditions.


Asunto(s)
Polímeros , Agua , Adsorción , Alquenos , Catálisis , Colorantes
13.
J Environ Manage ; 254: 109805, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31733474

RESUMEN

Industrial pollution is a great concern for modern society and developing cyclic processes is one of the major challenges. As far as we know, this work is the first to report the use of multiple white-rot fungi species for degrading a binary mixture of anionic dyes under solid state fermentation (SSF) conditions and a further physicochemical characterization of the residual biomass. First, eight white-rot fungi decolorized the dye mixture of brilliant blue FCF and allura red AC adsorbed onto corncob, reaching decolorizations between 11.47% and 87.64%. Then, I. lacteus, B. adusta and T. versicolor, based on the decolorization yield, were selected to evaluate the effect of carbon:nitrogen ratio, moisture content and inoculum quantity on the decolorization percentage. The factorial designs showed that C:N ratio had a negative effect while moisture and inoculum quantity a positive effect. In terms of the kinetics, the three white-rot fungi achieved their maximum decolorization level, around 80.11-86.04%, after 10-12 days. I. lacteus exhibited the highest decolorization percentage, even though only the enzyme manganese peroxidase was detected, with a maximum activity of 6.62 U gds-1 at day 14. Besides, T. versicolor was the only species with laccase activity, with a maximum of 15.94 U gds-1 at day 6 of fermentation. The physicochemical characterization of the biomass allowed to conclude that these aggregates represent a potential organic amendment, as for their significant oxidizable organic carbon (more than 9.5% on wet basis) and essential nutrients content, as well as for their low ash content (less than 1% on wet basis). Finally, for outlining an efficient bioremediation cycle, a cheap and effective methodology for drying the biomass at the end of the SSF process is required.


Asunto(s)
Colorantes , Lacasa , Biodegradación Ambiental , Biomasa , Suelo
14.
Chemosphere ; 240: 124940, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31574446

RESUMEN

Charged ultrafiltration (UF) membranes can repel electrically charged molecules that are smaller than the size of the membrane pores and display high rejection of solutes, high flux, and low operation pressures compared to uncharged UF, nanofiltration (NF) and reverse osmosis (RO). Here, a charged UF membrane composite (PANI/PVDF) was prepared and regulated via electrochemically reversible control in portions of amine/imine functional groups of PANI. As a result, the permeability and rejection ratios of CR2- on charged PANI/PVDF, with PVDF as a control, increased from 19.6 to a maximum of 183.3 L m-2 h-1 bar-1 and from 3.4% to 74%, which expands the trade-off confine benefited from surface potential change from -12.21 mV to -25.26 mV, furtherly, the rejection ratio of CR2- on PANI/PVDF reached up to 93% via the electrochemical regulation. Finally, a fixed-charge model was built that well describes the steric and electric repulsion effects on membrane performance and the important roles of the electrochemically controllable surface charge. Moreover, the contour map of rejection ratios containing the ratio of molecular size vs the average pore size of the membrane (r/R = 0.2-1.0) and the zeta potential (-10 to -60 mV) were taken into account, which can be used to visually understand the rejection performance of membranes. This model is also appropriate for varying molecular sizes and for molecules with different charges. Our work opens a new horizon for the design of electrochemically controllable charged membranes to remove charged compounds.


Asunto(s)
Colorantes/análisis , Técnicas Electroquímicas/métodos , Ultrafiltración/métodos , Purificación del Agua/métodos , Electricidad , Membranas Artificiales , Propiedades de Superficie
15.
Chemosphere ; 239: 124763, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31526989

RESUMEN

Nonredox metal ions have been widely recognized to be important in a wide range of biological and chemical oxidations as Lewis acids (LA). However, the role of LA in peroxymonosulfate (PMS) activation for wastewater treatment has not been considered until now. This study shows that oxidizing power of PMS can be promoted after binding nonredox metal ions such as Ca2+ as LA, leading to the easier reduction of the oxidant to radicals and substantial enhancement of dye degradation by employing manganese oxides OMS-2 as model catalysts. Increased with Lewis acidity of the metal ion, the rate of PMS decomposition enhanced linearly, while the dye degradation rate first increased and then declined due to the formation of a larger amount of dioxygen. The interactions between Ca2+ and PMS were further investigated by Raman, cyclic voltammetry and XPS; and the detailed mechanism of PMS activation was proposed. The performance of Ca2++OMS-2/PMS system under different conditions was also studied. The findings indicate the importance of LA in PMS activation reaction and their role must be considered in other transition metal oxides/PMS systems. It will be also helpful to design new and highly active catalysts for the reactions.


Asunto(s)
Ácidos de Lewis/química , Compuestos de Manganeso/química , Óxidos/química , Peróxidos/química , Contaminantes Químicos del Agua/química , Calcio/química , Catálisis , Colorantes/química , Oxidantes/química , Oxidación-Reducción , Soluciones , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química
16.
Chemosphere ; 239: 124766, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31527001

RESUMEN

Iron (Fe)-doped ZrO2 tetragonal nanoparticles were synthesized by a facile and inexpensive hydrothermal technique, that were doped with Fe3+ ions (0.1, 0.3, and 0.5 mol%) into the host lattice without altering the morphology and crystal structure of the nanoparticles. SEM and TEM investigations indicated that the morphology of ZrO2 nanoparticles did not change even after incorporation of Fe, while the band gap of semiconducting ZrO2 nanoparticles was reduced from 4.97 to 1.77 eV. Such a in band gap was responsible to harvest more photons to stimulate the generation of more electrons in the valence band, thereby enhancing the photoelectrochemical (PEC) water splitting as well as photocatalytic and photoelectrocatalytic activities in the photodegradation of Rhodamine B. The 0.3 mol%-doped ZrO2 electrode showed enhanced photocurrent density (0.07 × 10-3 A/cm2), that was 45-times greater than the pure sample. The electrochemical impedance spectroscopy (EIS) confirmed that 0.3 mol%-doped ZrO2 exhibited the best charge transfer characteristics, which increased with PEC water splitting activity. The maximum photocurrent density and long-term photo-stability were achieved in the light on-off states.


Asunto(s)
Colorantes/aislamiento & purificación , Hierro/química , Nanopartículas del Metal/química , Rodaminas/aislamiento & purificación , Circonio/química , Catálisis , Colorantes/química , Electrodos , Contaminantes Ambientales/química , Contaminantes Ambientales/aislamiento & purificación , Fotoquímica/instrumentación , Fotoquímica/métodos , Fotólisis , Puntos Cuánticos/química , Rodaminas/química , Agua/química
17.
Chemosphere ; 239: 124764, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31527004

RESUMEN

Electrospun reduced graphene oxide/TiO2/poly(acrylonitrile-co-maleic acid) composite nanofibers (E-spun RGO/TiO2/PANCMA NFs) were fabricated using electrospinning of the dispersive solution of PANCMA, GO and TiO2 followed by post-chemical reduction. The obtained composite nanofibers were compressed in a dialyzer and then used to absorb and degrade malachite green (MG) and leucomalachite green (LMG) from aqueous solution. Compared to the E-spun TiO2/PANCMA and GO/TiO2/PANCMA NFs, the E-spun RGO/TiO2/PANCMA NFs exhibited higher adsorption capacity and photocatalytic degradation ability. Under optimized conditions, 90.6% of MG and 93.7% of LMG from 50 mL aqueous sample solution were adsorbed on the RGO/TiO2/PANMA NFs (3.0 mg fibers) in 2.0 min, and subsequent the 91.4% and 95.2% of MG and LMG adsorbed on the NFs were degradated in 60 min under UV irradiation, respectively. In addition, the E-spun RGO/TiO2/PANMA NFs exhibited good reusability and could be reused in multiple cycles of operations for adsorption and photocatalytic degradation of MG and LMG. This work demonstrated that the electrospun composite nanofibers are promising materials for removal of pollutants from environmental water samples.


Asunto(s)
Nanofibras/química , Colorantes de Rosanilina/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Resinas Acrílicas/química , Adsorción , Catálisis , Colorantes/química , Colorantes/aislamiento & purificación , Grafito/química , Procesos Fotoquímicos , Colorantes de Rosanilina/química , Titanio/química , Rayos Ultravioleta , Contaminantes Químicos del Agua/química
18.
Indian J Ophthalmol ; 68(1): 71-72, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31856471
19.
Sci Total Environ ; 700: 134536, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31689651

RESUMEN

Heterogeneous electro-Fenton (EF) technology has been wildly applied for the treatment of wastewater containing dyes and other organic pollutants. However, biologically treatment should be further applied after heterogeneous electro-Fenton process in order get better effluent quality. In the present study, a simple electropolymerization method using poly (3,4-ethylenedioxythiophene) (PEDOT) and graphene oxide (GO) was applied for graphite felt (GF) electrode modification as cathode in EF system, and coupling subsequently aerobic granular sludge (AGS) biological treatment for dye wastewater treatment. The modified electrode was characterized by scanning electron microscopy (SEM), Raman spectrum, and cyclic voltammetry (CV). Data implied that much higher H2O2 productivity, current response and coulomb efficiency (CE) were achieved by using GO/PEDOT:NaPSS modified GF. The results could be ascribed to the synergistic effect between PEDOT and GO that accelerated the electron transfer rate. Moreover, the H2O2 production capacity remained over 84.2% after 10-times reuses for GO/PEDOT:NaPSS modified GF, indicating that GO significantly improved the stability and life of electrode. Compared with the single system, the total organic carbon (TOC) and chemical oxygen demand (COD) removal efficiencies of the combined system degradation methylene blue (MB) wastewater were significantly improved. Therefore, this modified GF could be used as a potentially useful cathode in heterogeneous EF technology for actual wastewater treatment and the combined system have a promising engineering application value in MB wastewater degradation field.


Asunto(s)
Colorantes/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/química , Análisis de la Demanda Biológica de Oxígeno , Compuestos Bicíclicos Heterocíclicos con Puentes , Electrodos , Grafito , Peróxido de Hidrógeno , Azul de Metileno , Polímeros , Aguas del Alcantarillado , Aguas Residuales/química
20.
Biosci Biotechnol Biochem ; 84(1): 103-110, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31559912

RESUMEN

We previously reported that MDA-MB-231 and MCF-7 cells, which are breast cancer cell lines and have cancer and cancer-initiating cells (CICs), were killed following normothermic microwave irradiation in which the cellular temperature was maintained at 37°C. In this study, we investigated the percentages of live or dead cells among CD44+/CD24- cells, which were defined as CICs among MDA-MB-231 and MCF-7 cells, and other types of cells in response to microwave irradiation. CD44+/CD24- cells among MDA-MB-231 cells were killed, thereby decreasing the number of cells, whereas the number of live CD44+/CD24- MCF-7 cells was increased following microwave irradiation. Moreover, adhesion, invasion, and migration were decreased in MDA-MB-231 cells, and the activation of matrix metalloproteinase-2 (MMP-2) in MDA-MB-231 cells was increased following microwave irradiation. These decreased cell activities might have been caused by MMP-2 activation and population changes in CD44+/CD24- in MDA-MB-231 cells.Abbreviations: APC: allophecocyanin; CBB: coomassie Brilliant Blue; CD: cluster of differentiation; CICs: cancer-initiating cells; FACS: fluorescence-activated cell sorting; FBS: fetal bovine serum; FITC: fluorescein isothiocyanate; FTDT: finite-difference time domain; HER2: human epidermal growth factor receptor type 2; PI: propidium iodide.


Asunto(s)
Antígeno CD24/metabolismo , Adhesión Celular/efectos de la radiación , Movimiento Celular/efectos de la radiación , Receptores de Hialuranos/metabolismo , Microondas , Neoplasias de la Mama Triple Negativas/patología , Apoptosis/efectos de la radiación , Recuento de Células , Colorantes/metabolismo , Femenino , Citometría de Flujo , Humanos , Células MCF-7 , Metaloproteinasa 2 de la Matriz/metabolismo , Invasividad Neoplásica , Propidio/metabolismo , Temperatura Ambiental
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