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1.
Small ; 18(1): e2104958, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34825485

RESUMEN

The efficiency of CO2 electroreduction has been largely limited by the activity of the catalysts as well as the three-phase interface. Herein, a multiscale strategy is proposed to synthesize hierarchical nanofibers covered by carbon nanotubes and embedded with cobalt nanoparticles (Co/CNT/HCNF). The confinement effect of carbon nanotubes can restrict the diameter of the cobalt particles down to several nanometers and prevent the easy corrosion of these nanoparticles. The three-dimensional carbon nanofibers, in size range of several hundred nanometers, improve the electrochemically active surface area, facilitate electron transfer, and accelerate CO2 transportation. These cross-linked carbon nanofibers eventually form a freestanding Co/CNT/HCNF membrane of dozens of square centimeters. Consequently, Co/CNT/HCNF produces CO with 97% faradaic efficiency at only -0.4 VRHE cathode potential in an H-type cell. From the regulation of catalyst nanostructure to the design of macrography devices, Co/CNT/HCNF membrane can be directly used as the gas-diffusion compartment in a flow cell device. Co/CNT/HCNF membrane generates CO with faradaic efficiencies higher than 90% and partial current densities greater than 300 mA cm-2 for at least 100-h stability. This strategy provides a successful example of efficient catalysts for CO2 electroreduction and also has the feasibility in other self-standing energy conversion devices.

2.
Future Oncol ; 16(10): 525-540, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32148087

RESUMEN

Aim: Our aim was to analyze the clinicopathological features of lung, liver, bone and brain metastasis in patients with endometrial cancer (EC). Patients & methods: We screened patients diagnosed with EC between 2010 and 2015 from the Surveillance, Epidemiology and End Results database. Results: Among 69,027 eligible EC patients, lung metastasis was the most common. Patients with lung or liver metastasis were at higher risk of bone and brain metastases than those without lung and liver metastasis. Brain metastasis has the lowest survival time (5.0 months) in single organ metastasis. Liver and brain metastasis have the highest death rate in two organ metastasis, and lung, liver and brain metastasis had the lowest survival time (1.0 month) in multi-sites metastasis. Conclusion: Lung metastasis was the most common in EC patients. Assessing distant organ metastasis may help clinicians to determine appropriate follow-up strategy for patients with EC.


Asunto(s)
Neoplasias Endometriales/mortalidad , Neoplasias Endometriales/patología , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Metástasis de la Neoplasia , Pronóstico , Programa de VERF , Tasa de Supervivencia
3.
Microb Pathog ; 113: 396-402, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29101062

RESUMEN

The antibacterial effect and mechanism of eugenol from Syzygium aromaticum (L.) Merr. & L. M. Perry (clove) leaf essential oil (CLEO) against oral anaerobe Porphyromonas gingivalis were investigated. The results showed that eugenol, with content of 90.84% in CLEO, exhibited antibacterial activity against P. gingivalis at a concentration of 31.25 µM. Cell shrink and lysis caused by eugenol were observed with Scanning Electron Microscopy (SEM). The release of macromolecules and uptake of fluorescent dye indicated that the antibacterial activity was due to the ability of eugenol to permeabilize the cell membrane and destroy the integrity of plasmatic membrane irreversibly. In addition, eugenol inhibited biofilm formation and reduced preformed biofilm of P. gingivalis at different concentrations. The down-regulation of virulence factor genes related to biofilm (fimA, hagA, hagB, rgpA, rgpB, kgp) explained that eugenol suppressed biofilm formation at the initial stage. These findings suggest that eugenol and CLEO may be potential additives in food and personal healthcare products as a prophylactic approach to periodontitis.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Eugenol/farmacología , Aceites Volátiles/farmacología , Exudados de Plantas/farmacología , Hojas de la Planta/química , Porphyromonas gingivalis/efectos de los fármacos , Syzygium/química , Biopelículas/crecimiento & desarrollo , Membrana Celular/efectos de los fármacos , Membrana Celular/ultraestructura , Permeabilidad de la Membrana Celular/efectos de los fármacos , Regulación hacia Abajo , Cromatografía de Gases y Espectrometría de Masas/métodos , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Genes Bacterianos/genética , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/química , Periodontitis/microbiología , Aceites de Plantas/química , Aceites de Plantas/farmacología , Porphyromonas gingivalis/citología , Porphyromonas gingivalis/genética , Porphyromonas gingivalis/crecimiento & desarrollo , Factores de Virulencia/genética
4.
Nan Fang Yi Ke Da Xue Xue Bao ; 34(8): 1140-4, 2014 Jul.
Artículo en Chino | MEDLINE | ID: mdl-25176082

RESUMEN

OBJECTIVE: To investigate the effect of adrenomedullin (ADM) on renal arteriole remodeling and phosphorylation of extracellular signal-regulated protein kinases 1/2 (p-ERK1/2) in spontaneous hypertensive rats (SHR). METHODS: Male SHR (4 weeks old) were randomized into hypertensive group (SHR) and ADM-treated group (ADM) to receive subcutaneous saline and ADM injections (daily dose of 1.0 nmol/kg, 5 days a week), respectively, with age-matched Wistar-Kyota (WKY) rats as the blank control. The systolic blood pressure (SBP) was measured at the end of each week, and histological changes of the renal arterioles were observed using HE and Weigert staining; the expression of P-ERK1/2 in the arterioles was detected with immunohistochemistry and Western blotting. RESULTS: At 16 and 24 weeks of age, the rats in both SHR and ADM groups showed significantly higher SBP levels than WKY rats (P<0.05), and at 24 weeks, SBP was significantly lower in ADM group than in SHR group (P<0.05). The intima thickness/lumen diameter (IT/LD) ratio of the renal arterioles increased in both SHR and ADM groups at 16 and 24 weeks as compared with that of WKY rats (P<0.05), and for arterioles with an outer diameter <40 µm, the IT/LD ratio was significantly lower at 24 weeks in ADM group than in SHR group (P<0.05). The renal expression of p-ERK1/2, which increased significantly in SHR and ADM groups at 16 and 24 weeks (P<0.05), was significantly lower in ADM group than in SHR group at 24 weeks (P<0.05). CONCLUSIONS: Long-term ADM treatment can control SPB elevation in SHR rats and reduce renal arteriole remodeling by inhibiting the phosphorylation of ERK1/2.


Asunto(s)
Adrenomedulina/farmacología , Arteriolas/efectos de los fármacos , Remodelación Vascular , Animales , Presión Sanguínea , Hipertensión , Riñón/irrigación sanguínea , Masculino , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Ratas , Ratas Endogámicas SHR , Ratas Wistar
5.
J Cosmet Sci ; 64(1): 35-44, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23449129

RESUMEN

This study was conducted to investigate the protective effects of epigallocatechin-3-gallate (EGCG) on hydrogen peroxide (H2O2)-induced oxidative stress injury in human dermal fibroblasts. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay and the use of Hoechst staining and terminal deoxynucleotidyl transferase dUTP nick end labeling for apoptosis detection indicated that the administration of H2O2 to human dermal fibroblasts caused cell damage and apoptosis. The incubation of human dermal fibroblasts with EGCG markedly inhibited the human dermal fibroblast injury induced by H2O2. The assay for 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity indicated that EGCG had a direct, concentration-dependent antioxidant activity. Treatment of human dermal fibroblasts with EGCG significantly reversed the H2O2-induced decrease of superoxide dismutase (SOD) and glutathione peroxidase (GSH-px), and the inhibition of malondialdehyde (MDA) levels. These results showed that EGCG possessed antioxidant activity and was effective against H2O2-induced human dermal fibroblast injury by enhancing the activity of SOD and GSH-px, and by decreasing the MDA level. Our results suggested that EGCG should have the potential to be used further in cosmetics and in the prevention of aging-related skin injuries.


Asunto(s)
Apoptosis/efectos de los fármacos , Catequina/análogos & derivados , Fibroblastos/efectos de los fármacos , Peróxido de Hidrógeno/efectos adversos , Piel/citología , Bencimidazoles , Compuestos de Bifenilo , Catequina/farmacología , Células Cultivadas , Depuradores de Radicales Libres/farmacología , Glutatión Peroxidasa/metabolismo , Humanos , Etiquetado Corte-Fin in Situ , Malondialdehído , Oxidación-Reducción , Picratos , Superóxido Dismutasa/metabolismo , Sales de Tetrazolio/farmacología , Tiazoles/farmacología
6.
J Zhejiang Univ Sci B ; 14(2): 97-105, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23365008

RESUMEN

Oat contains different components that possess antioxidant properties; no study to date has addressed the antioxidant effect of the extract of oat bran on the cellular level. Therefore, the present study focuses on the investigation of the protective effect of oat bran extract by enzymatic hydrolysates on human dermal fibroblast injury induced by hydrogen peroxide (H(2)O(2)). Kjeldahl determination, phenol-sulfuric acid method, and high-performance liquid chromatography (HPLC) analysis indicated that the enzymatic products of oat bran contain a protein amount of 71.93%, of which 97.43% are peptides with a molecular range from 438.56 to 1301.01 Da. Assays for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity indicate that oat peptide-rich extract has a direct and concentration-dependent antioxidant activity. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay and the TdT-mediated digoxigenin-dUTP nick-end labeling (TUNEL) assay for apoptosis showed that administration of H(2)O(2) in human dermal fibroblasts caused cell damage and apoptosis. Pre-incubation of human dermal fibroblasts with the Oatp for 24 h markedly inhibited human dermal fibroblast injury induced by H(2)O(2), but application oat peptides with H(2)O(2) at same time did not. Pre-treatment of human dermal fibroblasts with Oatp significantly reversed the H(2)O(2)-induced decrease of superoxide dismutase (SOD) and the inhibition of malondialdehyde (MDA). The results demonstrate that oat peptides possess antioxidant activity and are effective against H(2)O(2)-induced human dermal fibroblast injury by the enhanced activity of SOD and decrease in MDA level. Our results suggest that oat bran will have the potential to be further explored as an antioxidant functional food in the prevention of aging-related skin injury.


Asunto(s)
Avena/química , Fibroblastos/efectos de los fármacos , Fibroblastos/fisiología , Peróxido de Hidrógeno/farmacología , Extractos Vegetales/farmacología , Semillas/química , Fenómenos Fisiológicos de la Piel/efectos de los fármacos , Células Cultivadas , Niño , Citoprotección , Fibroblastos/patología , Humanos , Masculino
7.
Molecules ; 18(1): 1101-10, 2013 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-23325098

RESUMEN

Response surface methodology (RSM) using a central composite design (CCD) was employed to optimize the conditions for extraction of antioxidants from black soybean (Glycine max var) sprouts. Three influencing factors: liquid-solid ratio, period of ultrasonic assisted extraction and extraction temperature were investigated in the ultrasonic aqueous extraction. Then Response Surface Methodology (RSM) was applied to optimize the extraction process focused on DPPH radical-scavenging capacity of the antioxidants with respect to the above influencing factors. The best combination of each significant factor was determined by RSM design and optimum pretreatment conditions for maximum radical-scavenging capacity were established to be liquid-solid ratio of 29.19:1, extraction time of 32.13 min, and extraction temperature of 30 °C. Under these conditions, 67.60% of DPPH radical-scavenging capacity was observed experimentally, similar to the theoretical prediction of 66.36%.


Asunto(s)
Depuradores de Radicales Libres/aislamiento & purificación , Glycine max/química , Modelos Químicos , Extractos Vegetales/aislamiento & purificación , Compuestos de Bifenilo/química , Simulación por Computador , Depuradores de Radicales Libres/química , Radicales Libres/química , Picratos/química , Extractos Vegetales/química , Extracción en Fase Sólida/métodos , Sonido
8.
Molecules ; 17(10): 11669-79, 2012 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23027368

RESUMEN

Active ingredients in different lengths of black soybean sprouts were extracted with water. Concentrations of the main proteins and polysaccharides were determined by the Forint phenol assay and phenol-sulfuric acid assay, respectively. Anti-oxidizing capacities of the extracts were measured in vitro using the DPPH scavenging test and whitening capacity was measured in vitro using the tyrosinase inhibition test. The effects of the bean sprout extracts on human skin fibroblasts damnified by H2O2 were studied using an MTT colorimetric assay. The safety of the extracts was determined using the red blood cell (RBC) test, chick chorioallantoic membrane (CAM) assay and human patch test. Results show that DPPH radical scavenging rates at different shoot lengths were all greater than 95%, while the tyrosinase inhibition capacity of the extracts reached 98%. Hemolysis rate in all extracts were lower than 10%, below the 20% regulatory limit for the RBC test. No signs of allergic reactions were observed in the human patch tests. The optimum extract was obtained from bean sprouts grown to 0.5 cm. Extracts of black bean sprouts are safe and can be used as additives in anti-aging and whitening cosmetic products.


Asunto(s)
Cosméticos/química , Glycine max/química
9.
Life Sci ; 90(11-12): 424-31, 2012 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-22273755

RESUMEN

AIMS: Recent studies have shown that dermal fibroblasts possess multiple types of voltage-dependent K(+) channels, and the activation of these channels induces apoptosis. In the present study, we aimed to investigate whether hydrogen peroxide (H(2)O(2)), an oxidative stress inducer, could modulate these channels or induce human dermal fibroblasts injury. MAIN METHODS: The effects of H(2)O(2) on K(+) currents were studied using a whole-cell recording. Intracellular PKC levels were measured with a direct human PKC enzyme immunoassay kit. Cell viability was assessed using PI staining and apoptotic nuclei were detected with TdT-mediated digoxigenin-dUTP nick-end labelling assay (TUNEL) assay. KEY FINDINGS: Treatment of cells with 100µM H(2)O(2) resulted in a partially reversible increase in non-inactivating outward K(+) currents and an alteration in the steady-state activation property of the channels. The H(2)O(2)-induced increase in K(+) currents was mimicked by a PKC activator, and was blocked by the PKC inhibitor or the large conductance Ca(2+)-activited K(+) (BK) channel blockers. The intracellular PKC levels were significantly enhanced by H(2)O(2) treatment in a concentration-dependent manner. After exposure to H(2)O(2), evaluation of fibroblasts survival rate and damaged cell number with TUNEL-positive nuclei revealed an increased cell injury. Blocking the K(+) channels with blockers significantly decreased the H(2)O(2)-induced human dermal fibroblasts injury. SIGNIFICANCE: Our results revealed that H(2)O(2) could enhance BK currents by PKC pathway. Increased K(+) currents might be related to H(2)O(2)-induced human dermal fibroblasts injury. The results reported here contribute to our understanding of the mechanism underlying H(2)O(2)-induced human dermal fibroblasts injury.


Asunto(s)
Dermis/metabolismo , Fibroblastos/metabolismo , Peróxido de Hidrógeno/toxicidad , Canales de Potasio Calcio-Activados/metabolismo , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Dermis/citología , Humanos , Técnicas para Inmunoenzimas , Etiquetado Corte-Fin in Situ , Técnicas de Placa-Clamp , Proteína Quinasa C/metabolismo
10.
Wei Sheng Yan Jiu ; 31(1): 24-7, 2002 Feb.
Artículo en Chino | MEDLINE | ID: mdl-12561566

RESUMEN

In order to study whether Jingtian compound extracted from herbs could delay the process of skin aging, the skin on the back of Guinea pigs (6 and 15 months old) were shaved topically and applied with and without 0.5% Jingtian compound for 30 days by self-control design. The possible alterations caused by Jingtian compound were observed by histological and biochemical techniques. Results showed that the number and the activity of fibroblast in dermis was increased prominently compared with the control. The activities of superoxide dismutase, glutathion peroxidase and the hydroxyproline level of acid soluble collagen in dermis were enhanced, and the malondialdehyde content was inhibited concomitantly. It is suggested that Jingtian compound might play a protective role on skin aging.


Asunto(s)
Crassulaceae/química , Medicamentos Herbarios Chinos/farmacología , Envejecimiento de la Piel/efectos de los fármacos , Piel/química , Animales , Colágeno/metabolismo , Cosméticos , Medicamentos Herbarios Chinos/aislamiento & purificación , Femenino , Cobayas , Superóxido Dismutasa/metabolismo
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