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1.
Angew Chem Int Ed Engl ; 62(52): e202314480, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-37955417

RESUMEN

Deploying Ni-enriched (Ni≥95 %) layered cathodes for high energy-density lithium-ion batteries (LIBs) requires resolving a series of technical challenges. Among them, the structural weaknesses of the cathode, vigorous reactivity of the labile Ni4+ ion species, gas evolution and associated cell swelling, and thermal instability issues are critical obstacles that must be solved. Herein, we propose an intuitive strategy that can effectively ameliorate the degradation of an extremely high-Ni-layered cathode, the construction of ultrafine-scale microstructure and subsequent intergranular shielding of grains. The formation of ultrafine grains in the Ni-enriched Li[Ni0.96 Co0.04 ]O2 (NC96) cathode, achieved by impeding particle coarsening during cathode calcination, noticeably improved the mechanical durability and electrochemical performance of the cathode. However, the buildup of the strain-resistant microstructure in Mo-doped NC96 concurrently increased the cathode-electrolyte contact area at the secondary particle surface, which adversely accelerated parasitic reactions with the electrolyte. The intergranular protection of the refined microstructure resolved the remaining chemical instability of the Mo-doped NC96 cathode by forming an F-induced coating layer, effectively alleviating structural degradation and gas generation, thereby extending the battery's lifespan. The proposed strategies synergistically improved the structural and chemical durability of the NC96 cathode, satisfying the energy density, life cycle performance, and safety requirements for next-generation LIBs.

2.
Sci Rep ; 7: 46035, 2017 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-28378774

RESUMEN

The aim of the present study was to examine the antioxidative activity of (+)-lariciresinol (LRSL), an optically active lignan isolated from Rubia philippinensis in several in vitro assays. LRSL was also subjected to evaluate its inhibitory effect against the generation of reactive oxygen species (ROS) in murine macrophage (RAW 264.7) cells. The results showed that LRSL possessed very strong radical scavenging activity and reducing power, as well as inhibited ROS generation in a dose-dependent manner without showing any cytotoxicity. The transcriptional and translational levels of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were markedly higher in the sample treated group. LRSL treatment also increased the transcriptional and translational activities of NF-E2-related factor-2 (Nrf-2) with a corresponding increase in the transcriptional and translational activities of the heme oxygenase-1 (HO-1). LRSL activated p38 and treatments with SB239063 (a p38 inhibitor) suppressed the LRSL-induced activation of Nrf2, resulting in a decrease in HO-1 expression. Collectively, the data demonstrated that LRSL has potent antioxidative activity, decreasing ROS generation in RAW 264.7 cells and increasing the transcriptional and translational levels of antioxidant enzymes by activating Nrf2-mediated HO-1 induction via p38 signaling.


Asunto(s)
Antioxidantes/farmacología , Furanos/aislamiento & purificación , Furanos/farmacología , Hemo-Oxigenasa 1/metabolismo , Lignanos/aislamiento & purificación , Lignanos/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Rubia/química , Regulación hacia Arriba/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Amidinas , Animales , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Supervivencia Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Depuradores de Radicales Libres/farmacología , Furanos/química , Lignanos/química , Fase II de la Desintoxicación Metabólica , Ratones , Estrés Oxidativo/efectos de los fármacos , Fosforilación/efectos de los fármacos , Células RAW 264.7 , Especies Reactivas de Oxígeno/metabolismo
3.
Sci Rep ; 7: 45858, 2017 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-28393917

RESUMEN

In this study, the authors investigated the anti-melanogenic effects of 3,8-dihydroxyquinoline (jineol) isolated from Scolopendra subspinipes mutilans, the mechanisms responsible for its inhibition of melanogenesis in melan-a cells, and its antioxidant efficacy. Mushroom tyrosinase activities and melanin contents were determined in melan-a cells, and the protein and mRNA levels of MITF, tyrosinase, TYRP-1, and TYRP-2 were assessed. Jineol exhibited significant, concentration-dependent antioxidant effects as determined by DPPH, ABTS, CUPRAC, and FRAP assays. Jineol significantly inhibited mushroom tyrosinase activity by functioning as an uncompetitive inhibitor, and markedly inhibited melanin production and intracellular tyrosinase activity in melan-a cells. In addition, jineol abolished the expressions of tyrosinase, TYRP-1, TYRP-2, and MITF, thereby blocking melanin production and interfering with the phosphorylations of ERK1/2 and p38. Furthermore, specific inhibitors of ERK1/2 and p38 prevented melanogenesis inhibition by jineol, and the proteasome inhibitor (MG-132) prevented jineol-induced reductions in cellular tyrosinase levels. Taken together, jineol was found to stimulate MAP-kinase (ERK1/2 and p38) phosphorylation and the proteolytic degradation pathway, which led to the degradations of MITF and tyrosinase, and to suppress the productions of melanin.


Asunto(s)
Melaninas/genética , Factor de Transcripción Asociado a Microftalmía/genética , Monofenol Monooxigenasa/genética , Animales , Artrópodos/genética , Artrópodos/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Melaninas/biosíntesis , Melanocitos , Ratones , Proteínas Quinasas Activadas por Mitógenos/genética , Monofenol Monooxigenasa/química , Fosforilación/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/efectos de los fármacos , Proteolisis/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
4.
Front Microbiol ; 7: 2037, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28066360

RESUMEN

This study was undertaken to characterize a lactic acid bacterium 4I1, isolated from the freshwater fish, Zacco koreanus. Morphological, biochemical, and molecular characterization of 4I1 revealed it to be Pediococcus pentosaceus 4I1. The cell free supernatant (CFS) of P. pentosaceus 4I1 exhibited significant (p < 0.05) antibacterial effects (inhibition zone diameters: 16.5-20.4 mm) against tested foodborne pathogenic bacteria with MIC and MBC values of 250-500 and 500-1,000 µg/mL, respectively. Further, antibacterial action of CFS of P. pentosaceus 4I1 against two selected bacteria Staphylococcus aureus KCTC-1621 and Escherichia coli O157:H7 was determined in subsequent assays. The CFS of P. pentosaceus 4I1 revealed its antibacterial action against S. aureus KCTC-1621 and E. coli O157:H7 on membrane integrity as confirmed by a reduction in cell viability, increased potassium ion release (900 and 800 mmol/L), reduced absorption at 260-nm (3.99 and 3.77 OD), and increased relative electrical conductivity (9.9 and 9.7%), respectively. Gas chromatography-mass spectrometry (GC-MS) analysis of the CFS of P. pentosaceus 4I1 resulted in the identification of seven major compounds, which included amino acids, fatty acids and organic acids. Scanning electron microscopic-based morphological analysis further confirmed the antibacterial effect of CFS of P. pentosaceus 4I1 against S. aureus KCTC-1621 and E. coli O157:H7. In addition, the CFS of P. Pentosaceus 4I1 displayed potent inhibitory effects on biofilms formation by S. aureus KCTC-1621 and E. coli O157:H7. The study indicates the CFS of P. pentosaceus 4I1 offers an alternative means of controlling foodborne pathogens.

5.
Asian Pac J Trop Med ; 7(8): 602-608, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25149373

RESUMEN

OBJECTIVE: To examine the individual and synergistic anti-listerial effect of nisin and leaf essential oil of Metasequoia glyptostroboides (M. glyptostroboides) against one of the leading foodborne pathogens Listeria monocytogenes (L. monocytogenes) ATCC 19116 in milk samples. METHODS: The whole (8%), low (1%) and skim (no fat content) milk samples were inoculated with L. monocytogenes ATCC 19116 along with leaf essential oil of M. glyptostroboides or nisin alone as well in combinations. RESULTS: In this study, the leaf essential oil at the concentrations of 2% and 5% revealed strong anti-listerial effect against L. monocytogenes ATCC 19116 in all categories of milk samples. Nisin at the concentrations of 250 and 500 IU/mL displayed a strong inhibitory effect against ATCC 19116 as compared to the control group. Additionally, synergistic combinations of leaf essential oil (1%) and nisin (62.5, 125, 250 and 500 IU/mL) also had a remarkable anti-listerial synergism in all the tested milk samples including whole, low and skim milk after 14 days. CONCLUSIONS: As a major finding, the leaf essential oil of M. glyptostroboides might be a useful candidate for using in food industry to control the growth of foodborne pathogenic bacteria as confirmed by its potent anti-listerial synergistic effect with nisin against L. monocytogenes ATCC 19116 in different milk samples.


Asunto(s)
Antibacterianos/farmacología , Cupressaceae/química , Listeria monocytogenes/efectos de los fármacos , Leche/microbiología , Nisina/farmacología , Aceites Volátiles/farmacología , Animales , Antibacterianos/química , Recuento de Colonia Microbiana , Microbiología de Alimentos , Nisina/química , Aceites Volátiles/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/química
6.
Tissue Eng Part A ; 19(21-22): 2373-81, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23701237

RESUMEN

Fibrin glue has been widely investigated as a cell delivery vehicle for improving the therapeutic effects of mesenchymal stem cells (MSCs). Implanted MSCs produce their therapeutic effects by secreting paracrine factors and by replacing damaged tissues after differentiation. While the influence of fibrin glue on the differentiation potential of MSCs has been well documented, its effect on paracrine function of MSCs is largely unknown. Herein we investigated the influence of fibrin glue on the paracrine effects of MSCs. MSCs were isolated from human adipose tissue. The effects of fibrin glue on survival, migration, secretion of growth factors, and immune suppression of MSCs were investigated in vitro. MSCs in fibrin glue survived and secreted growth factors such as the vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) over 14 days. VEGF and immune modulators, including the transforming growth factor (TGF)-ß1 and prostaglandin E2, secreted from MSCs in fibrin glue significantly increased under inflammatory conditions. Thus, MSCs in fibrin glue effectively suppressed immune reactions. In addition, fibrin glue protected the MSCs from oxidative stress and prevented human dermal fibroblast death induced by exposure to extreme stress. In contrast, MSCs within fibrin glue hardly migrated. These results suggest that fibrin glue may sustain survival of implanted MSCs and their paracrine function. Our results provide a mechanistic data to allow further development of MSCs with fibrin glue as a clinical treatment.


Asunto(s)
Adhesivo de Tejido de Fibrina/farmacología , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Humanos , Células Madre Mesenquimatosas/metabolismo
7.
Food Chem Toxicol ; 49(1): 109-14, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20934478

RESUMEN

This study was undertaken to evaluate the effect of nisin and cone essential oil of Metasequoia glyptostroboides against Listeria monocytogenes ATCC 19116 inoculated in whole (8%), low (1%) and skim (no fat content) milks. Essential oil at the concentrations of 2% and 5% revealed strong antilisterial effect against L. monocytogenes ATCC 19116 in all categories of milks. Nisin at the concentrations of 250 and 500 IU/ml displayed a remarkable antilisterial effect as compared to the control group. Also, the synergistic combinations of cone essential oil (1% and 2%) and nisin (62.5, 125, 250 and 500 IU/ml) had a remarkable antilisterial activity in all categories of whole, low and skim milks after 14 days. Results of this study indicate that the cone essential oil of M. glyptostroboides might be a useful candidate for using in food industry to control the growth of pathogenic microorganisms.


Asunto(s)
Listeria monocytogenes/efectos de los fármacos , Leche/microbiología , Nisina/farmacología , Aceites Volátiles/farmacología , Tracheophyta/química , Animales , Sinergismo Farmacológico , Listeria monocytogenes/aislamiento & purificación
8.
Food Chem Toxicol ; 48(5): 1350-4, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20206225

RESUMEN

This study was undertaken to examine the efficacy of essential oil from seeds of Zizyphus jujuba for its potential role on hair growth by in vivo method. Essential oil was applied at different concentrations (0.1%, 1% and 10%) over the shaved skin onto the backs of BALB/c mice and monitored for 21 days. After 21 days, mice treated with 1% and 10% of oil produced a greater effect on the length of hair which were measured to be 9.96 and 10.02 mm, respectively, as compared to the control (8.94 mm). We measured the weight of hair/cm(2) area of dorsal skin and also evaluated hair thickness and hair follicles microscopically after plucking the hair immediately from the shaved area of mice and found the best results for 1% of essential oil-treated mice. From this study, it is concluded that Z. jujuba essential oil possesses hair growth promoting activity.


Asunto(s)
Cabello/efectos de los fármacos , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Ziziphus/química , Animales , Femenino , Cabello/crecimiento & desarrollo , Folículo Piloso/efectos de los fármacos , Folículo Piloso/crecimiento & desarrollo , Ratones , Ratones Endogámicos BALB C , Extractos Vegetales/farmacología , Semillas/química , Piel/efectos de los fármacos
9.
Food Chem Toxicol ; 48(2): 639-43, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19944733

RESUMEN

This study was undertaken to evaluate the effect of essential oil from seeds of Zizyphus jujuba on TPA-induced skin inflammation in experimental mice. Exposure of TPA on the ear of the BALB/c mice caused a marked increase in both ear thickness and skin water content. The ear thickness was measured for TPA-induced ear was 0.54 mm, as compared to control (0.23 mm). Treatment with 1% and 10% of essential oil caused significant decrease in ear thicknesses which were measured to be 0.30 and 0.35 mm, as well as reduce the water content about 51% and 53% in the TPA-induced skin inflammation model, respectively. Furthermore, histological analysis clearly confirmed that Z. jujuba essential oil inhibited the inflammatory responses of skin inflammation in animal model. Therefore, our findings demonstrate that the essential oil of Z. jujuba seeds might accelerate the development of new drugs for various inflammatory diseases.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Otitis Externa/tratamiento farmacológico , Aceites de Plantas/farmacología , Ziziphus/química , Animales , Modelos Animales de Enfermedad , Oído Externo/efectos de los fármacos , Edema/inducido químicamente , Edema/tratamiento farmacológico , Edema/patología , Femenino , Ratones , Ratones Endogámicos BALB C , Otitis Externa/inducido químicamente , Otitis Externa/patología , Aceites de Plantas/química , Semillas/química , Acetato de Tetradecanoilforbol/farmacología
10.
Food Chem Toxicol ; 47(10): 2606-12, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19635519

RESUMEN

This study was carried out to assess the antioxidant and antidermatophytic activities of the essential oil and extracts of Magnolia liliflora Desr. Antioxidant activity was evaluated by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The free radical scavenging activities of the oil and ethyl acetate extract were found to be superior (IC(50) values=10.11 and 16.17 microg/ml, respectively) as compared to butylatedhydreoxyanisole (BHA), (IC(50) value=18.27 microg/ml). Also the ethyl acetate extract revealed the highest phenolic contents (96.13 mg/g of dry wt) as compared to the other extracts. Further, the oil (1000 microg/disc) and extracts (1500 microg/disc) revealed 42.36-63.12% and 19.07-54.14% antidermatophytic effect, respectively along with their respective MIC values ranging from 62.5 to 500 and 250 to 2000 microg/ml against the members of Trichophyton and Microsporum spp. Also the oil had strong detrimental effect on spore germination of tested fungal pathogens as well as concentration and time dependent kinetic inhibition of Microsporum canis KCTC 6348. The results of this study justify a potential role of M. liliflora to serve as a natural antioxidant and antidermatophytic agent.


Asunto(s)
Antifúngicos/farmacología , Depuradores de Radicales Libres/farmacología , Magnolia/química , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Antifúngicos/química , Compuestos de Bifenilo/química , Hidroxianisol Butilado/farmacología , Depuradores de Radicales Libres/química , Radicales Libres/química , Pruebas de Sensibilidad Microbiana , Microsporum/efectos de los fármacos , Aceites Volátiles/química , Fenoles/análisis , Picratos/química , Extractos Vegetales/química , Trichophyton/efectos de los fármacos
11.
Appl Microbiol Biotechnol ; 83(6): 1127-33, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19415265

RESUMEN

This study was undertaken to assess the in vitro antifungal potential of the essential oil and n-hexane, chloroform, ethyl acetate, and methanol extracts of Nandina domestica Thunb. against dermatophytes, the casual agents of superficial infections in animals and human beings. The oil (1,000 microg/disc) and extracts (1,500 microg/disc) revealed 31.1-68.6% and 19.2-55.1% antidermatophytic effect against Trichophyton rubrum KCTC 6345, T. rubrum KCTC 6375, T. rubrum KCTC 6352, Trichophyton mentagrophytes KCTC 6085, T. mentagrophytes KCTC 6077, T. mentagrophytes KCTC 6316, Microsporum canis KCTC 6591, M. canis KCTC 6348, and M. canis KCTC 6349, respectively, along with their respective minimum inhibitory concentration values ranging from 62.5 to 500 and 125 to 2,000 microg/ml. Also, the oil had strong detrimental effect on spore germination of all the tested dermatophytic fungi as well as concentration and time-dependent kinetic inhibition of T. rubrum KCTC 6375. The present results demonstrated that N. domestica mediated oil and extracts could be potential sources of natural fungicides to control certain important dermatophytic fungi.


Asunto(s)
Antifúngicos/farmacología , Arthrodermataceae/efectos de los fármacos , Berberidaceae/química , Aceites Volátiles/farmacología , Compuestos Orgánicos/farmacología , Animales , Antifúngicos/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Humanos , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/aislamiento & purificación , Compuestos Orgánicos/aislamiento & purificación , Esporas Fúngicas/efectos de los fármacos , Factores de Tiempo
12.
Food Chem Toxicol ; 47(6): 1355-61, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19303043

RESUMEN

This study was undertaken to assess the antioxidant and antidermatophytic potential of the essential oil and extracts (hexane, chloroform, ethyl acetate and methanol) of Metasequoia glyptostroboides Miki ex Hu. Antioxidant activity was evaluated by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The free radical scavenging activities of the oil and ethyl acetate extract were found to be superior (IC(50)=9.1 and 14.24 microg/ml, respectively) as compared to butylatedhydroxyanisole (BHA), (IC(50)=18.27 microg/ml). Also the ethyl acetate extract revealed the highest phenolic contents (93.26 mg/g of dry wt) as compared to the other extracts. Further, oil (1250 microg/disc) and extracts (1750 microg/disc) revealed 35.33-67.66 and 18.0-53.3% antidermatophytic effect, respectively, along with their respective MIC values (62.5-500 and 250-4000 microg/ml) against Trichophyton rubrum KCTC 6345, T. rubrum KCTC 6375, T. rubrum KCTC 6352, T. mentagrophytes KCTC 6085, T. mentagrophytes KCTC 6077, T. mentagrophytes KCTC 6316, Microsporum canis KCTC 6591, M. canis KCTC 6348 and M. canis KCTC 6349. The oil also had a strong detrimental effect on spore germination as well as concentration and time-dependent kinetic inhibition of M. canis KCTC 6591.


Asunto(s)
Antifúngicos , Antioxidantes/química , Arthrodermataceae/efectos de los fármacos , Aceites Volátiles/farmacología , Sequoia/química , Arthrodermataceae/crecimiento & desarrollo , Compuestos de Bifenilo , Dermatomicosis/tratamiento farmacológico , Dermatomicosis/microbiología , Humanos , Cinética , Pruebas de Sensibilidad Microbiana , Picratos , Extractos Vegetales/farmacología , Esporas Fúngicas/efectos de los fármacos , Esporas Fúngicas/crecimiento & desarrollo
13.
Food Chem Toxicol ; 47(2): 449-53, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19095037

RESUMEN

Cleistocalyx operculatus (Roxb.) Merr and Perry buds (Myrtaceae) are widely used in folk medicine for the treatment of gastric ailments as well as an antiseptic agent in China, Vietnam and some other tropical countries. However, to be clinically useful, more scientific data are needed. In the present study, we investigated the in vitro and in vivo anti-inflammatory activities of the essential oil of the C. operculatus buds (EO-CO). In the applied tests, EO-CO significantly inhibited lipopolysaccharide (LPS)-induced secretion of pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta), in RAW 264.7 cells, a mouse macrophage-like cell line. Also the mRNA expression of TNF-alpha and IL-1beta was suppressed by treatment with EO-CO in LPS-stimulated RAW 264.7 cells. Moreover, reporter gene analysis revealed that the EO-CO significantly blocked LPS-induced transcriptional activation of NF-kappaB in RAW 264.7 cells. Nuclear translocation of p65 subunit was also suppressed by EO-CO treatment. In addition, EO-CO inhibited phorbol ester-induced increase in ear swelling and skin water content in BALB/c mice. These results suggest that EO-CO might exert an anti-inflammatory effect by suppressing the expression of pro-inflammatory cytokines which is mediated, at least in part, by blocking NF-kappaB activation.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Citocinas/metabolismo , Medicamentos Herbarios Chinos/farmacología , Macrófagos/efectos de los fármacos , Myrtaceae/química , Aceites de Plantas/farmacología , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Citocinas/genética , Oído Externo/efectos de los fármacos , Oído Externo/patología , Edema/inducido químicamente , Edema/patología , Edema/prevención & control , Femenino , Expresión Génica/efectos de los fármacos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Ratones , Ratones Endogámicos BALB C , FN-kappa B/genética , FN-kappa B/metabolismo , ARN Mensajero/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
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