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1.
ACS Appl Mater Interfaces ; 15(34): 40267-40279, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37594128

RESUMEN

Transdermal cancer therapy faces great challenges in clinical practice due to the low drug transdermal efficiency and the unsatisfactory effect of monotherapy. Herein, we develop a novel bubble pump microneedle system (BPMN-CuS/DOX) by embedding sodium bicarbonate (NaHCO3) into hyaluronic acid microneedles (MNs) loaded with fucoidan-based copper sulfide nanoparticles (Fuc-CuS NPs) and doxorubicin (DOX). BPMN-CuS/DOX can generate CO2 bubbles triggered by an acidic tumor microenvironment for deep and rapid intradermal drug delivery. Fuc-CuS NPs exhibit excellent photothermal effect and Fenton-like catalytic activity, producing more reactive oxygen species (ROS) by photothermal therapy (PTT) and chemodynamic therapy (CDT), which enhances the antitumor efficacy of DOX and reduces the dosage of its chemotherapy (CT). Simultaneously, DOX increases intracellular hydrogen peroxide (H2O2) supplementation and promotes the sustained production of ROS. BPMN-CuS/DOX significantly inhibits melanoma both in vitro and in vivo by the combination of CDT, PTT, and CT. In short, our study significantly enhances the effectiveness of transdermal drug delivery by constructing BPMNs and provides a promising novel strategy for transdermal cancer treatment with multiple therapies.


Asunto(s)
Melanoma , Melanoma/terapia , Sulfato de Cobre/química , Terapia Fototérmica , Doxorrubicina/uso terapéutico , Antibióticos Antineoplásicos/uso terapéutico , Terapia Combinada , Masculino , Animales , Ratones , Línea Celular Tumoral , Ratones Endogámicos C57BL
2.
J Mater Chem B ; 9(35): 7216-7228, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-35226035

RESUMEN

The integration of chemodynamic therapy (CDT) and photothermal therapy (PTT) has played a huge role in improved anticancer treatments. Here, a novel multifunctional nanoplatform based on Cu2-xS conjugated NaYF4:Yb/Er@NaYF4:Yb upconversion nanoparticles (UCNPs) was proposed and designed. In the UCNPs-Cu2-xS nanocomposites, UCNPs with excellent luminescent properties and a high X-ray attenuation coefficient can serve as an upconversion luminescence (UCL) and computer tomography (CT) imaging contrast agent; meanwhile, Cu(II) in the Cu2-xS nanodots enables the nanocomposites to have a magnetic resonance imaging (MRI) ability owing to the presence of unpaired electrons. Moreover, the Cu2-xS nanodots with a strong absorbance in the NIR II biowindow not only could be employed as a stable photothermal agent under NIR laser irradiation, but also could be used as a photothermal-enhanced Fenton nanocatalyst to respond to over-expressed H2O2 in the tumor microenvironment (TME) and generate toxic hydroxyl radicals (˙OH) to effectively kill cancer cells. Furthermore, the UCNPs-Cu2-xS nanocomposites possess negligible cytotoxicity and a high photothermal conversion efficiency (43.8%) in the NIR-II biowindow (1064 nm), indicating that they possess great potential for the UCL/CT/MR multi-modal imaging guided synergistic enhanced CDT/PTT of cancer.


Asunto(s)
Sulfato de Cobre/química , Nanocompuestos , Neoplasias , Línea Celular Tumoral , Humanos , Peróxido de Hidrógeno , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Fototerapia , Terapia Fototérmica
3.
ACS Appl Mater Interfaces ; 12(16): 18342-18351, 2020 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-32223204

RESUMEN

Therapeutic efficacy of synergistic photodynamic therapy (PDT) and photothermal therapy (PTT) is limited by complex conjugation chemistry, absorption wavelength mismatch, and inadequate biodegradability of the PDT-PTT agents. Herein, we designed biocompatible copper sulfide nanodot anchored folic acid-modified black phosphorus nanosheets (BP-CuS-FA) to overcome these limitations, consequently enhancing the therapeutic efficiency of PDT-PTT. In vitro and in vivo assays reveal good biocompatibility and commendable tumor inhibition efficacy of the BP-CuS-FA nanoconjugate because of the synergistic PTT-PDT mediated by near-infrared laser irradiation. Importantly, folic acid unit could target folate receptor overexpressed cancer cells, leading to enhanced cellular uptake of BP-CuS-FA. BP-CuS-FA also exhibits significant contrast effect for photoacoustic imaging, permitting its in vivo tracking. The photodegradable character of BP-CuS-FA is associated with better renal clearance after the antitumor therapy in vivo. The present research may facilitate further development on straightforward approaches for targeted and imaging-guided synergistic PDT-PTT of cancer.


Asunto(s)
Antineoplásicos , Nanoconjugados/química , Fósforo , Técnicas Fotoacústicas/métodos , Fototerapia/métodos , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Sulfato de Cobre/química , Femenino , Ácido Fólico/química , Ratones , Ratones Endogámicos BALB C , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/terapia , Fósforo/química , Fósforo/farmacocinética , Fósforo/farmacología , Fósforo/uso terapéutico , Nanomedicina Teranóstica/métodos
4.
Sci Rep ; 9(1): 4701, 2019 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-30886163

RESUMEN

Despite their promising thermo-physical properties for direct solar absorption, carbon-based nanocolloids present some drawbacks, among which the unpleasant property of being potentially cytotoxic and harmful to the environment. In this work, a sustainable, stable and inexpensive colloid based on coffee is synthesized and its photo-thermal properties investigated. The proposed colloid consists of distilled water, Arabica coffee, glycerol and copper sulphate, which provide enhanced properties along with biocompatibility. The photo-thermal performance of the proposed fluid for direct solar absorption is analysed for different dilutions and compared with that of a traditional flat-plate collector. Tailor-made collectors, opportunely designed and realized via 3D-printing technique, were used for the experimental tests. The results obtained in field conditions, in good agreement with two different proposed models, show similar performance of the volumetric absorption using the proposed coffee-based colloids as compared to the classical systems based on a highly-absorbing surface. These results may encourage further investigations on simple, biocompatible and inexpensive colloids for direct solar absorption.


Asunto(s)
Materiales Biocompatibles/química , Café/química , Coloides/química , Coffea , Sulfato de Cobre/química , Glicerol/química , Modelos Químicos , Fenómenos Físicos , Energía Solar , Agua/química
5.
Environ Pollut ; 242(Pt B): 1236-1244, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30118911

RESUMEN

This paper evaluates the UV photodegradation of 17ß-estradiol (E2) on silica gel and in natural soil with different soil components. Silica gel was chosen as a stable and pure support to simulate the photochemical behavior of E2 on the surface of natural soil. Ultraviolet light, rather than visible light, was confirmed to play a decisive role in the photodegradation of E2 on silica gel. The effect of three soil components, including humic acid (HA), inorganic salts, and relative humidity (RH), on the photochemical behavior of E2 on silica gel or soil under UV irradiation was then evaluated. Two HA concentrations (10 and 20 mg g-1) and three salts (ferric sulfate, copper sulfate and sodium carbonate) were observed to obviously inhibit the degradation of E2 on silica gel. Interestingly, nitrate was found to obviously improve the removal efficiency of E2. Both too-dry and too-wet conditions obviously reduced the removal rate of E2, and the optimum relative humidity (RH) value was found to be approximately about 35% (30 °C). Furthermore, twenty intermediate products and two major pathways were proposed to describe the transformation processes of E2 treated by UV irradiation, among which oligomers were found to be the major intermediate products before complete mineralization. The efficient UV removal of E2 on silica gel and natural soil suggested a feasible strategy to remediate E2 contaminated soil.


Asunto(s)
Estradiol/metabolismo , Fotólisis , Gel de Sílice/química , Contaminantes del Suelo/metabolismo , Suelo/química , Rayos Ultravioleta , Carbonatos/química , Sulfato de Cobre/química , Compuestos Férricos/química , Sustancias Húmicas/análisis , Nitratos/química , Contaminantes del Suelo/análisis
6.
Phys Med Biol ; 63(6): 06NT01, 2018 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-29528035

RESUMEN

Recent developments in radiation therapy aimed at more precise dose delivery along with higher dose gradients (dose painting) and more efficient dose delivery with higher dose rates e.g. flattening filter free (FFF) irradiation. Magnetic-resonance-imaging based polymer gel dosimetry offers 3D information for precise dose delivery techniques. Many of the proposed polymer gels have been reported to exhibit a dose response, measured as relaxation rate ΔR2(D), which is dose rate dependent. A lack of or a reduced dose-rate sensitivity is very important for dosimetric accuracy, especially with regard to the increasing clinical use of FFF irradiation protocols with LINACs at high dose rates. Some commonly used polymer gels are based on Methacrylic-Acid-Gel-Initiated-by-Copper (MAGIC). Here, we report on the dose sensitivity (ΔR2/ΔD) of MAGIC-type gels with different oxygen scavenger concentration for their specific dependence on the applied dose rate in order to improve the dosimetric performance, especially for high dose rates. A preclinical x-ray machine ('Yxlon', E = 200 kV) was used for irradiation to cover a range of dose rates from low [Formula: see text] min = 0.6 Gy min-1 to high [Formula: see text] max = 18 Gy min-1. The dose response was evaluated using R2-imaging of the gel on a human high-field (7T) MR-scanner. The results indicate that all of the investigated dose rates had an impact on the dose response in polymer gel dosimeters, being strongest in the high dose region and less effective for low dose levels. The absolute dose rate dependence [Formula: see text] of the dose response in MAGIC-type gel is significantly reduced using higher concentrations of oxygen scavenger at the expense of reduced dose sensitivity. For quantitative dose evaluations the relative dose rate dependence of a polymer gel, normalized to its sensitivity is important. Based on this normalized sensitivity the dose rate sensitivity was reduced distinctly using an increased oxygen scavenger concentration with reference to standard MAGIC-type gel formulation at high dose rate levels. The proposed gel composition with high oxygen scavenger concentration exhibits a larger linear active dose response and might be used especially in FFF-radiation applications and preclinical dosimetry at high dose rates. We propose in general to use high dose rates for calibration and evaluation as the change in relative dose sensitivity is reduced at higher dose rates in all of the investigated gel types.


Asunto(s)
Ácido Ascórbico/química , Sulfato de Cobre/química , Depuradores de Radicales Libres/química , Gelatina/química , Hidroquinonas/química , Imagen por Resonancia Magnética/métodos , Metacrilatos/química , Oxígeno/química , Polímeros/química , Radiometría/métodos , Ácido Ascórbico/efectos de la radiación , Calibración , Sulfato de Cobre/efectos de la radiación , Gelatina/efectos de la radiación , Humanos , Hidroquinonas/efectos de la radiación , Metacrilatos/efectos de la radiación , Polímeros/efectos de la radiación , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador
7.
Appl Biochem Biotechnol ; 183(1): 200-217, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28247310

RESUMEN

Sweet sorghum (Sorghum sp.) has high biomass yield. Hydrolysis of lignocellulosic sweet sorghum bagasse (SSB) to fermentable sugar could be useful for manufacture of biofuel or other fermentation products. Pretreatment of lignocellulosic biomass to degrade lignin before enzymatic hydrolysis is a key step. Fungal pretreatment of SSB with combined CuSO4-gallic acid supplements in solid-state fermentation (SSF) to achieve higher lignin degradation, selectivity value (SV), and enzymatic hydrolysis to sugar was studied. Coriolus versicolor was selected due to high activities of ligninolytic enzymes laccase, lignin peroxidase (LiP), manganese peroxidase (MnP), polyphenol oxidase (PPO), and arylalcohol oxidase (AAO) and low activities of cellulolytic enzymes CMCase, FPase, and ß-glucosidase with high lignin degradation and SV in 20 days. CuSO4/gallic acid increased the activities of ligninolytic enzymes resulting in enhanced lignin degradations and SVs. Cumulative/synergistic effect of combined supplements further increased the activities of laccase, LiP, MnP, PPO, and AAO by 7.6, 14.6, 2.67, 2.06, and 2.15-folds, respectively (than control), resulting in highest lignin degradation 31.1 ± 1.4% w/w (1.56-fold) and SV 2.33 (3.58-fold). Enzymatic hydrolysis of pretreated SSB yielded higher (~2.2 times) fermentable sugar. The study showed combined supplements can improve fungal pretreatment of lignocellulosic biomass. XRD, SEM, FTIR, and TGA/DTG of SSB confirmed the results.


Asunto(s)
Agaricales/enzimología , Celulosa/química , Sulfato de Cobre/química , Proteínas Fúngicas/metabolismo , Ácido Gálico/química , Lignina/química , Sorghum/química , Lacasa/metabolismo , Oxidorreductasas/metabolismo
8.
Lett Appl Microbiol ; 61(4): 381-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26218531

RESUMEN

UNLABELLED: The aim of the study was to compare the antimicrobial activities of freshly made, heat-treated (HT) and 14 day stored (+)-Catechin solutions with (+)-catechin flavanol isomers in the presence of copper sulphate. (+)-Catechin activity was investigated when combined with different ratios of Cu(2+) ; 100°C heat treatment; autoclaving; and 14 day storage against Staphylococcus aureus. Cu(2+) -(+)-Catechin complexation, isomer structure-activity relationships, and H2 O2 generation were also investigated. Freshly made, HT, and 14 day stored flavanols showed no activity. While combined Cu(2+) -autoclaved (+)-Catechin and -HT(+)-Catechin activities were similar, HT(+)-Catechin was more active than either freshly made (+)-catechin (generating more H2 O2 ) or (-)-Epicatechin (though it generated less H2 O2 ) or 14 day-(+)-Catechin (which had similar activity to Cu(2+) controls-although it generated more H2 O2 ). When combined with Cu(2+) , in terms of rates of activity, HT(+)-Catechin was lower than (-)-Epigallocatechin gallate and greater than freshly made (+)-Catechin. Freshly made and HT(+)-Catechin formed acidic complexes with Cu(2+) as indicated by pH and UV-vis measurements although pH changes did not account for antimicrobial activity. Freshly made and HT(+)-Catechin both formed Cu(2+) complexes. The HT(+)-Catechin complex generated more H2 O2 which could explain its higher antimicrobial activity. SIGNIFICANCE AND IMPACT OF THE STUDY: Natural products attract considerable attention in the search for novel antimicrobials, prebiotics and antioxidants. Enhanced biological activity of natural products has been demonstrated with chemical and heat treatment. This article extends the few publications on heat treatments of plant products and combinations with adjuncts, to raise antimicrobial activity against pathogens such as Staphylococcus aureus. We demonstrated that heat treatment could increase the activity of (+)-Catechin, a weak antimicrobial flavanol found commonly in plants in the presence of copper sulphate. Heat treatment of readily available resources merits consideration in the development of more potent substances for use in clinical settings and agriculture.


Asunto(s)
Antibacterianos/farmacología , Catequina/farmacología , Sulfato de Cobre/química , Peróxido de Hidrógeno/metabolismo , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/química , Catequina/análogos & derivados , Catequina/química , Sulfato de Cobre/farmacología , Calor , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/crecimiento & desarrollo , Relación Estructura-Actividad
9.
Appl Biochem Biotechnol ; 176(4): 1162-73, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25926011

RESUMEN

Cellulose producing bacteria were isolated from fruit samples and kombucha tea (a fermented beverage) using CuSO4 solution in modified Watanabe and Yamanaka medium to inhibit yeasts and molds. Six bacterial strains showing cellulose production were isolated and identified by 16S rRNA gene sequencing as Gluconacetobacter xylinus strain DFBT, Ga. xylinus strain dfr-1, Gluconobacter oxydans strain dfr-2, G. oxydans strain dfr-3, Acetobacter orientalis strain dfr-4, and Gluconacetobacter intermedius strain dfr-5. All the cellulose-producing bacteria were checked for the cellulose yield. A potent cellulose-producing bacterium, i.e., Ga. xylinus strain DFBT based on yield (cellulose yield 5.6 g/L) was selected for further studies. Cellulose was also produced in non- conventional media such as pineapple juice medium and hydrolysed corn starch medium. A very high yield of 9.1 g/L cellulose was obtained in pineapple juice medium. Fourier transform infrared spectrometer (FT-IR) analysis of the bacterial cellulose showed the characteristic peaks. Soft cellulose with a very high water holding capacity was produced using limited aeration. Scanning electron microscopy (SEM) was used to analyze the surface characteristics of normal bacterial cellulose and soft cellulose. The structural analysis of the polymer was performed using (13)C solid-state nuclear magnetic resonance (NMR). More interfibrillar space was observed in the case of soft cellulose as compared to normal cellulose. This soft cellulose can find potential applications in the food industry as it can be swallowed easily without chewing.


Asunto(s)
Acetobacter/metabolismo , Frutas/microbiología , Genes Bacterianos , Gluconacetobacter xylinus/metabolismo , Gluconacetobacter/metabolismo , Té de Kombucha/microbiología , Acetobacter/clasificación , Acetobacter/genética , Acetobacter/aislamiento & purificación , Ananas/microbiología , Bebidas , Reactores Biológicos , Celulosa/metabolismo , Celulosa/ultraestructura , Sulfato de Cobre/química , Fermentación , Gluconacetobacter/clasificación , Gluconacetobacter/genética , Gluconacetobacter/aislamiento & purificación , Gluconacetobacter xylinus/clasificación , Gluconacetobacter xylinus/genética , Gluconacetobacter xylinus/aislamiento & purificación , Malus/microbiología , Musa/microbiología , Filogenia , Polisacáridos Bacterianos/biosíntesis , Polisacáridos Bacterianos/ultraestructura , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Espectroscopía Infrarroja por Transformada de Fourier , Almidón/metabolismo , Zea mays/microbiología
10.
J Hazard Mater ; 286: 75-84, 2015 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-25559861

RESUMEN

Toxicity testing of nanomaterials (NMs) is experimentally challenging because NMs may interfere with test environment and assay components. In this work we propose a simple and reliable method--a 'spot test' to compare biocidal potency of NMs to unicellular microorganisms such as bacteria, yeasts and algae. The assay is straightforward: cells are incubated in deionized water suspensions of NMs for up to 24h and then pipetted as a 'spot' on agarized medium. Altogether seven bacterial strains, yeast and a microalga were tested. CuO, TiO2 and two different Ag NPs, multi-wall C-nanotubes (MWCNTs), AgNO3, CuSO4, 3,5-dichlorophenol, triclosan and H2O2 were analyzed. The biocidal potency of tested substances ranged from 0.1mg/L to >1000 mg/L; whereas, the least potent NMs toward all test species were TiO2 NPs and MWCNTs and most potent Ag and CuO NPs. Based on the similar toxicity pattern of the tested chemicals on the nine unicellular organisms in deionized water we conclude that toxicity mechanism of biocidal chemicals seems to be similar, whatever the organism (bacteria, yeast, alga). Therefore, when the organisms are not 'protected' by their environment that usually includes various organic and inorganic supplements their tolerance to toxicants is chemical- rather than organism-dependent.


Asunto(s)
Cobre/química , Escherichia coli/efectos de los fármacos , Peróxido de Hidrógeno/química , Nanoestructuras/química , Saccharomyces cerevisiae/efectos de los fármacos , Plata/química , Staphylococcus aureus/efectos de los fármacos , Contaminantes del Agua/química , Agar/química , Materiales Biocompatibles/química , Clorofenoles/química , Sulfato de Cobre/química , Medios de Cultivo/química , Metales Pesados , Pruebas de Sensibilidad Microbiana , Nanotubos de Carbono/química , Nitrato de Plata/química , Temperatura , Titanio/química , Pruebas de Toxicidad , Triclosán/química
11.
Arch Anim Nutr ; 68(5): 370-84, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25179553

RESUMEN

This study aimed to compare the effects of organic (proteinate) and inorganic (sulphate) copper (Cu) and zinc (Zn) supplements, in presence or absence of a mannan oligosaccharide (MOS) supplement, on mineral solubility and digestibility in pigs. Twenty-eight barrows (25 ± 4 kg) assigned randomly to four treatment groups were fed a corn-wheat-soya bean meal diet with 10 mg/kg of Cu and 100 mg/kg of Zn supplied as organic or inorganic supplement, and supplemented or not with 0.1% MOS. After an adaptation period, total faeces and urine were collected for a period of 6-7 days. Pigs were then euthanatised and digesta from ileum and caecum were collected. Apparent digestibility was calculated in ileum and caecum using titanium dioxide. The organic mineral supplement improved total (faecal) digestibility and retained/ingested ratio of Cu (p < 0.05) while reducing apparent digestibility of Zn in the ileum (p < 0.05) without effect on total digestibility of Zn. Solubilities of Cu and Zn in liquid fraction of ileum and caecum were not affected by mineral sources. Although MOS supplement increased Cu solubility in the ileum (p < 0.05), it had no effect on digestibility of Zn and Cu in ileum, caecum and faeces, retained/ingested ratio of Zn and Cu, or pH and volatile fatty acid concentration in ileal and caecal digesta. In conclusion, organic mineral supplement improved total digestibility and retained/ingested ratio of Cu in pigs but this cannot be attributed to its solubility in ileal and caecal digesta. The MOS supplement did not interfere with digestibility or dietary utilisation of Zn and Cu in pigs fed above the Zn and Cu requirements.


Asunto(s)
Sulfato de Cobre/metabolismo , Suplementos Dietéticos , Mananos/administración & dosificación , Oligosacáridos/administración & dosificación , Porcinos/fisiología , Compuestos de Zinc/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Animales Recién Nacidos , Sulfato de Cobre/administración & dosificación , Sulfato de Cobre/química , Digestión , Heces/química , Masculino , Porcinos/crecimiento & desarrollo , Aumento de Peso , Compuestos de Zinc/administración & dosificación , Compuestos de Zinc/química
12.
Dalton Trans ; 43(30): 11709-15, 2014 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-24950757

RESUMEN

The semiconductor compounds have been proven to be promising candidates as a new type of photothermal therapy agent, but unsatisfactory photothermal conversion efficiencies limit their widespread application in photothermal therapy (PTT). Herein, we synthesized cysteine-coated CuS nanoparticles (Cys-CuS NPs) as highly efficient PTT agents by a simple aqueous solution method. The Cys-CuS NPs have a good biocompatibility owing to their biocompatible cysteine coating and exhibit a strong absorption in the near-infrared region due to the localized surface plasma resonances of valence-band free carriers. The photothermal conversion efficiency of Cys-CuS NPs reaches 38.0%, which is much higher than that of the recently reported Cu9S5 and Cu(2-x)Se nanocrystals. More importantly, tumor growth can be efficiently inhibited in vivo by the fatal heat arising from the excellent photothermal effect of Cys-CuS NPs at a low concentration under the irradiation of a 980 nm laser with a safe power density of 0.72 W cm(-2). Therefore, the Cys-CuS NPs have great potential as ideal photothermal agents for cancer therapy.


Asunto(s)
Sulfato de Cobre/farmacología , Cisteína/química , Nanopartículas del Metal , Fototerapia/métodos , Animales , Materiales Biocompatibles , Sulfato de Cobre/química , Células HeLa , Calor , Humanos , Ratones , Neoplasias Experimentales/terapia , Osteosarcoma/terapia
13.
Environ Sci Technol ; 47(19): 11258-67, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23971725

RESUMEN

Although nanotechnology advancements should be fostered, the environmental health and safety (EHS) of nanoparticles used in technologies must be quantified simultaneously. However, most EHS studies assess the potential implications of the free nanoparticles which may not be directly applicable to the EHS of particles incorporated into in-use technologies. This investigation assessed the aquatic toxicological implications of copper oxide (CuO) nanospheres relative to CuO nanorods used in nanoenergetic applications to improve combustion. Particles were tested in both the as-received form and following combustion of a CuO/aluminum nanothermite. Results indicated nanospheres were more stable in water and slowly released ions, while higher surface area nanorods initially released more ions and were more toxic but generally less stable. After combustion, particles sintered into larger, micrometer-scale aggregates, which may lower toxicity potential to pelagic organisms due to deposition from water to sediment and reduced bioavailability after complexation with sediment organic matter. Whereas the larger nanothermite residues settled rapidly, implying lower persistence in water, their potential to release dissolved Cu was higher which led to greater toxicity to Ceriodaphnia dubia relative to parent CuO material (nanosphere or rod). This study illustrates the importance of considering the fate and toxicology of nanoparticles in context with their relevant in-use applications.


Asunto(s)
Óxido de Aluminio/toxicidad , Cobre/toxicidad , Nanosferas/toxicidad , Nanotubos/toxicidad , Óxido de Aluminio/química , Animales , Cladóceros/efectos de los fármacos , Cobre/química , Sulfato de Cobre/química , Sulfato de Cobre/toxicidad , Nanosferas/química , Nanotubos/química
14.
Ultramicroscopy ; 134: 207-13, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23830376

RESUMEN

The atomic structure and interfaces of CdS/Cu2S heterostructured nanorods are investigated with the aberration-corrected TEAM 0.5 electron microscope operated at 80 kV and 300 kV applying in-line holography and complementary techniques. Cu2S exhibits a low-chalcocite structure in pristine CdS/Cu2S nanorods. Under electron beam irradiation the Cu2S phase transforms into a high-chalcocite phase while the CdS phase maintains its wurtzite structure. Time-resolved experiments reveal that Cu(+)-Cd(2+) cation exchange at the CdS/Cu2S interfaces is stimulated by the electron beam and proceeds within an undisturbed and coherent sulfur sub-lattice. A variation of the electron beam current provides an efficient way to control and exploit such irreversible solid-state chemical processes that provide unique information about system dynamics at the atomic scale. Specifically, we show that the electron beam-induced copper-cadmium exchange is site specific and anisotropic. A resulting displacement of the CdS/Cu2S interfaces caused by beam-induced cation interdiffusion equals within a factor of 3-10 previously reported Cu diffusion length measurements in heterostructured CdS/Cu2S thin film solar cells with an activation energy of 0.96 eV.


Asunto(s)
Compuestos de Cadmio/química , Sulfato de Cobre/química , Tomografía con Microscopio Electrónico/métodos , Nanotubos/química , Sulfuros/química , Electrones
15.
J AOAC Int ; 95(6): 1725-32, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23451390

RESUMEN

The aim of this investigation was to determine the bioactive compounds in kiwifruit as an indication of quality after extraction using methanol and ethyl acetate. Using FTIR and three-dimensional fluorescence spectroscopy and electrospray ionization/MS, the contents of polyphenols, flavonoids, flavanols, and tannins, and the level of the antioxidant activity by 2, 2-azino-bis (3-ethyl-benzothiazoline-6-sulfonic acid) diammonium salt, 1, 1-diphenyl-2-picrylhydrazyl, ferric-reducing/ antioxidant power, and cupric reducing antioxidant capacity assays were determined and compared. It was found that the methanol extracts of kiwifruit showed significantly higher amounts of bioactive acetate extracts. The cultivar Bidan, in comparison compounds and antioxidant activities than the ethyl with the classic Hayward, showed significantly higher bioactivity. For the first time, Bidan organic kiwifruit was analyzed for its antioxidant activities and compared with the widely consumed Hayward organic based on its bioactive compounds and fluorescence properties. Relatively high content of bioactive compounds and positive antioxidant and antiproliferative properties of kiwifruit determined by the advanced analytical methods justify its use as a source of valuable antioxidants. The methods used are applicable for bioactivity determination, in general, for any food products.


Asunto(s)
Actinidia/química , Frutas/química , Antineoplásicos Fitogénicos/química , Antioxidantes/análisis , Ácido Ascórbico/análisis , Benzotiazoles/análisis , Compuestos de Bifenilo/química , Proliferación Celular/efectos de los fármacos , Cromanos/química , Colorantes/química , Sulfato de Cobre/química , Compuestos Férricos/química , Flavonoides/análisis , Flavonoles/análisis , Indicadores y Reactivos , Fenoles/análisis , Picratos/química , Extractos Vegetales/análisis , Polifenoles/análisis , Espectrometría de Fluorescencia , Espectrometría de Masa por Ionización de Electrospray , Espectroscopía Infrarroja por Transformada de Fourier , Ácidos Sulfónicos/análisis , Taninos/análisis , Sales de Tetrazolio/química , Tiazoles/química
16.
ChemSusChem ; 3(10): 1200-3, 2010 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-20872400

RESUMEN

The oxidation of starch, xylans, potato flesh and wheat flour by H(2)O(2), in the presence of MSO(4) (M=Cu, Fe) as catalyst, led to depolymerization, and formation of solutions containing polyhydroxycarboxylic acids. Some of these oxidized compounds facilitate the process, leading to efficient transformations even with very low amounts of catalyst.


Asunto(s)
Ácidos Carboxílicos/síntesis química , Sulfato de Cobre/química , Compuestos Ferrosos/química , Peróxido de Hidrógeno/química , Oxidantes/química , Polisacáridos/química , Ácidos Carboxílicos/química , Catálisis , Hidróxidos/química , Oxidación-Reducción , Solanum tuberosum/química , Soluciones/química , Almidón/química , Triticum/química , Xilanos/química
17.
J Med Food ; 13(5): 1167-75, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20626255

RESUMEN

The overproduction of free radicals and oxygen reactive species is suspected to be implicated in a wide range of metabolic reactions that can have pernicious consequences in the development of a variety of human diseases. Botanical extracts are sources of antioxidants that counteract both free radicals and oxygen reactive species. The processing conditions used in the botanical extraction may influence the antioxidant composition; therefore, different extracts from the same plant may have different antioxidant properties. To illustrate this fact, we conducted a study using three commercial rosemary (Rosmarinus officinalis L.) leaf extracts. The three extracts were standardized to contain, respectively, 20% carnosic acid, 40% ursolic acid, or 20% rosmarinic acid. They were evaluated for their total (hydrophilic + lipophilic) antioxidant effects on oxygen radical absorbance capacity (ORAC), their ferric reducing/antioxidant power (FRAP), and their capacity to inhibit Cu(2+)-induced low-density lipoprotein (LDL) oxidation ex vivo. The ursolic acid extract showed the lowest antioxidant capacity on all models. The rosmarinic acid extract had an antioxidant capacity 1.5 times higher on ORAC and four times higher on FRAP than the carnosic acid extract. However, the carnosic acid extract was better than the rosmarinic acid extract in inhibiting the oxidation of LDL ex vivo. These results encourage conducting further studies to evaluate the carnosic acid and rosmarinic acid extracts in vivo. Our study offers an example of the importance of the extraction procedures, on which depends the nature of the antioxidant composition, and highlights interest to proceed with in vitro/ex vivo assay selection for the evaluation of the antioxidant properties of botanical extracts.


Asunto(s)
Antioxidantes/análisis , Extractos Vegetales/normas , Hojas de la Planta/química , Rosmarinus/química , Abietanos/análisis , Antioxidantes/farmacología , Cinamatos/análisis , Sulfato de Cobre/química , Depsidos/análisis , Compuestos Férricos/química , Lipoproteínas LDL/química , Oxidación-Reducción , Extractos Vegetales/análisis , Extractos Vegetales/química , Extractos Vegetales/farmacología , Especies Reactivas de Oxígeno/química , Triterpenos/análisis , Ácido Rosmarínico , Ácido Ursólico
18.
Chem Pharm Bull (Tokyo) ; 58(7): 934-8, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20606340

RESUMEN

The production of sesquiterpene-type phytoalexins with a vetispyradiene skeleton by Hyoscyamus albus hairy roots induced by methyl jasmonate (MeJA) was reported in a previous paper. The production pattern on co-treatment with cupper sulfate and MeJA (CuSO(4)-MeJA) showed a TLC profile differing from that on treatment with MeJA. Thus, we studied the production of phytoalexins on hairy root culture involving co-treatment with CuSO(4)-MeJA. In the experiment, many sesquiterpene-type phytoalexins with a vetispyradiene skeleton were isolated, most of which were different from the products reported in the previous paper. Here, we isolated four new phytoalexins (1-4) along with known compounds 5-10 from the culture medium of H. albus hairy roots co-treated with MeJA-CuSO(4). The structures of the new compounds (1-4) were determined as: (3R,4S,5R,7S,9R)-3-acetoxy-9-(2-methylpropionyloxy)solavetivone (1), (3R,4S,5R,7S,9R)-3-hydroxy-9-(3-methylbutanoyloxy)solavetivone (2), (3R,4S,5R,7S,9R)-3-acetoxy-9-(3-methyl-butanoyloxy)solavetivone (3), and (3R,4S,5R,7S,9R)-3-acetoxy-9-(3-methyl-2-butenoyloxy)-solavetivone (4) based on MS and NMR including 2D-NMR data. These findings indicated that the production of phytoalexins in H. albus hairy roots yielded different products based on treatment with different chemicals (CuSO(4), MeJA, and MeJA-CuSO(4)).


Asunto(s)
Acetatos/farmacología , Sulfato de Cobre/farmacología , Ciclopentanos/farmacología , Hyoscyamus/metabolismo , Oxilipinas/farmacología , Sesquiterpenos/química , Acetatos/química , Sulfato de Cobre/química , Ciclopentanos/química , Hyoscyamus/química , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Conformación Molecular , Oxilipinas/química , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/metabolismo , Fitoalexinas
19.
J Anim Physiol Anim Nutr (Berl) ; 94(5): e138-44, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20546066

RESUMEN

The study was conducted to investigate the effect of copper-loaded chitosan nanoparticles on the composition and metabolism of the caecal microbiota in rats. Forty male Sprague-Dawley (SD) rats (average body weight of 82 ± 5 g) were randomly assigned to five groups (n = 8). The dietary treatments were: (i) basal diet, (ii) basal diet + 80 mg/kg BW CuSO(4), (iii) basal diet + 80 mg/kg BW chitosan (CS-I), (iv) basal diet + 80 mg/kg BW copper-loaded chitosan nanoparticles (CSN-I) and (v) basal diet + 160 mg/kg BW copper-loaded chitosan nanoparticles (CSN-II). The trial lasted 21 days. The results showed that compared with control, Average day gain (ADG) of group CSN-I and CSN-II increased (p < 0.05). No significant difference was found in CuSO(4) or CS-I-treated groups (p > 0.05). There were no effects of these treatments on average day feed intake (ADFI) of rats (p > 0.05). The counts of Bifidobacteria and Lactobacillus in group CSN-II were higher than those of the control group (p < 0.05), while the counts of total aerobes, total anaerobes, Salmonella, Clostridium and coliform were lower than those of the control (p < 0.05). The activity of ß-glucuronidase in group CSN-I or CSN-II was significantly depressed (p < 0.05), while the activities of α-galactosidase and ß-galactosidase were enhanced significantly (p < 0.05). The pH of the caecum digesta and the concentration of propionate and butyrate in group CSN-I and CSN-II were higher than those of the control group (p < 0.05). No significant difference was found in these parameters in CuSO(4) or CS-I-treated groups (p > 0.05). The results indicate that the microbiota and environment of caecum are beneficially changed by the administration of copper-loaded CSN.


Asunto(s)
Ciego/microbiología , Quitosano/química , Sulfato de Cobre/química , Sulfato de Cobre/metabolismo , Nanopartículas/química , Alimentación Animal , Animales , Dieta , Suplementos Dietéticos , Masculino , Ratas , Ratas Sprague-Dawley
20.
Drug Chem Toxicol ; 33(2): 173-82, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20307144

RESUMEN

Chlorophytum borivilianum is a very popular herb in traditional Indian medicine and used as a potent "Rasayana" drug in "Ayurveda" as a rejuvenator. Currently, a large body of evidence supports the key role of free radicals in diverse pathological conditions such as aging and atherosclerosis. The present investigation essentially focuses on the comprehensive account of in vitro antioxidant activity exerted by C.borivilianum root extracts (i.e., aqueous and ethanolic), to clarify the pharmacological antagonism of chemicals/metals-mediated oxidation. Graded-dose (25 to 1000 microg/ml) of aqueous extract exhibited higher antioxidant potency as evidenced by powerful nitric oxide, superoxide, hydroxyl, DPPH and ABTS(*+) radicals scavenging activity along with reducing capacity (Fe(3+)/ferricyanide complex and FRAP assays), metal chelating ability, as well as markedly suppressed the lipid peroxidation in mitochondrial fractions as compared to ethanolic extract. Further, aqueous extract significantly decreased (P < 0.05) copper-mediated human serum and kinetics of LDL oxidation, as demonstrated by prolongation of lag phase time with decline of oxidation rate, conjugated dienes, lipid hydroperoxides and thiobarbituric acid reactive substances. In addition, the total polyphenol and flavonoid contents of aqueous extract were higher than that of ethanolic extract, which indicated a positive correlation between antioxidant activity and contents of total phenols. The IC(50) values of both extracts were also compared with appropriate antioxidant standards. Overall, aqueous extract of C.borivilianum root has significant powerful antioxidant activity and may favorably affect atherosclerosis risk status by reducing LDL oxidation susceptibility.


Asunto(s)
Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , Liliaceae/química , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Animales , Sulfato de Cobre/química , Flavonoides/análisis , Radicales Libres/química , Humanos , Técnicas In Vitro , Peroxidación de Lípido/efectos de los fármacos , Lipoproteínas LDL/química , Lipoproteínas LDL/efectos de los fármacos , Masculino , Medicina Ayurvédica , Mitocondrias Hepáticas/efectos de los fármacos , Mitocondrias Hepáticas/metabolismo , Óxido Nítrico/química , Oxidación-Reducción/efectos de los fármacos , Fenoles/análisis , Raíces de Plantas/química , Plantas Medicinales , Polifenoles , Ratas
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