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1.
Adv Sci (Weinh) ; 10(11): e2205141, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36683241

RESUMO

The recent application of the internet of things demands the ubiquitous utilization of data and electrical power. Even with the development of a wide variety of energy-harvesting technologies, few studies have reported a device transporting electrical energy and data simultaneously. This paper reports an electrostatic induction nanogenerator (ESING) consisting of a one-dimensional metastructure that can modulate the output voltage based on the resonance of ultrasound waves to transmit energy and data simultaneously. The ESING device is fabricated using electronegative poly(vinylidene fluoride) (PVDF) membrane using a phase inversion process. The output voltage from the ESING device exhibits periodic resonant peaks as the gap between the PVDF membrane and the Al electrode changes, showing an up to 35-fold difference between the maximum and minimum output voltages depending on the resonance state. The energy and electrical signal can be transmitted simultaneously in free space because the ESING converts energy from high-frequency ultrasound waves. This paper provides proof of concept for a data and energy-transferable smart tag device based on ESING devices exhibiting resonant and non-resonant states. A device consisting of four ESINGs for a 4-bit signal is implemented to demonstrate 16 signals.

2.
ACS Appl Mater Interfaces ; 11(40): 36917-36924, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31529962

RESUMO

Here, we report an efficient inverted red indium phosphide (InP) comprising QD (InP/ZnSe/ZnS, core/shell structure) light-emitting diode (QLED) by modulating an interfacial contact between the electron transport layer and emissive InP-QDs and applying self-aging approach. The red InP-QLED with optimized interfacial contact exhibits a significant improvement in maximum external quantum efficiency and current efficiency from 4.42 to 10.2% and 4.70 to 10.8 cd/A, respectively, after 69 days of self-aging, which is an almost 2.3-fold improvement compared to the fresh device. The analysis indicates the consecutive reduction in electron injection and accumulation in the emissive QD due to changes in the conduction band minimum of ZnMgO (0.1 eV after 10 days of storage) through a downward vacuum-level shift according to the aging times. During the device aging periods, the oxygen vacancy of ZnMgO reduces, which leads to lower the conductivity of ZnMgO. As a result, charge balance of the device is improved with the suppression of exciton quenching at the interface of ZnMgO and InP-QD.

3.
J Ginseng Res ; 37(4): 442-50, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24233437

RESUMO

The aim of this study was to determine and compare the preventive effect of Korean White Ginseng and Red Ginseng on oxidative stress in H2O2-treated HepG2 cells. The roots of ginseng were extracted with 70% methanol and partitioned with butanol to obtain saponin fractions, which have been known as bioactive constituents of ginseng. 2',7'-Dichlorofluorescein diacetate (DCF-DA) assay and malondialdehyde (MDA) content were measured for evaluating intracellular reactive oxygen species (ROS) generation. Also, mRNA expressions and activities of antioxidant enzymes were analyzed to determine the antioxidant activity of saponin or non-saponin fractions of ginsengs. According to DCF-DA assay, H2O2-induced MDA release and ROS generation were significantly reduced by treatment with saponin fractions of white and red ginseng roots. Also, saponin fractions increased effectively intracellular antioxidant enzyme activities including catalase, glutathione peroxidase and superoxide dismutase in H2O2- treated HepG2 hepatoma cells. In general, red ginseng was more effective than white ginseng for reducing oxidative stress. These results indicate that administration of red ginseng may certainly contribute relatively stronger than white ginseng to prevent from damaging liver function by oxidative stress.

4.
J Ginseng Res ; 37(2): 248-53, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23717177

RESUMO

Leaves from Panax ginseng Meyer (Korean origin and Chinese origin of Korean ginseng) and P. quinquefolius (American ginseng) were harvested in Haenam province, Korea, and were analyzed to investigate patterns in major metabolites using HPLC-based metabolic profiling. Partial least squares discriminant analysis (PLS-DA) was used to analyze the HPLC chromatogram data. There was a clear separation between Panax species and/or origins from different countries in the PLS-DA score plots. The ginsenoside compounds of Rg1, Re, Rg2, Rb2, Rb3, and Rd in Korean leaves were higher than in Chinese and American ginseng leaves, and the Rb1 level in P. quinquefolius leaves was higher than in P. ginseng (Korean origin or Chinese origin). HPLC chromatogram data coupled with multivariate statistical analysis can be used to profile the metabolite content and undertake quality control of Panax products.

5.
Nat Prod Res ; 27(11): 1037-40, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22607357

RESUMO

We isolated a sesquiterpene lactone from the methanol extract of the roots of Cosmos bipinnatus, namely, MDI (a mixture of dihydrocallitrisin and isohelenin). The anti-inflammatory activity of MDI was evaluated using lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. MDI significantly inhibited the expression of inducible nitric oxide synthase and cyclooxygenase-2. Consistent with these results, the production of NO and prostaglandin E2 (PGE2) was suggested to be suppressed by MDI in a concentration-dependent manner (IC50 value was 0.94 and 2.88 µg mL(-1) for NO and PGE2, respectively). In addition, MDI significantly inhibited the expressions of pro-inflammatory cytokines such as IL-1ß, IL-6, IFN-γ and TNF-α. Furthermore, MDI attenuated DNA-binding activity of NF-κB by inhibiting the phosphorylation of IκB. These results indicate that MDI isolated from the roots of C. bipinnatus shows anti-inflammatory activity in LPS-stimulated murine macrophages by modulating the NF-κB pathway.


Assuntos
Anti-Inflamatórios/farmacologia , Asteraceae/química , Lipopolissacarídeos/farmacologia , Raízes de Plantas/química , Animais , Linhagem Celular , Camundongos
6.
Nutr Res ; 32(9): 718-26, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23084645

RESUMO

Nutritional antioxidants interact with cells in an active mode, including retrieving and sparing one another, to diminish oxidative stress. However, the intracellular balance of prooxidants and antioxidants becomes unbalanced, favoring prooxidants during the aging process. One hypothesis is that an aging-associated increase in oxidative stress is the primary cause of aging. Hence, the research hypothesis for this study is that Korean red ginseng reduces oxidative stress in vivo. Therefore, we investigated the efficacy of Korean red ginseng water extract (GWE) in reducing aging-associated oxidative stress by measuring lipid peroxidation and antioxidant levels in older rats compared with young rats. We observed a significant increase in the markers for oxidative damage (eg, lipid peroxidation) and markers for vital organ damage (eg, aspartate aminotransferase, alanine aminotransferase, urea, and creatinine levels) in aged rats. The oxidative damage was accompanied by a significant decrease in enzymatic antioxidants such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione-S-transferase, and nonenzymatic antioxidants such as reduced glutathione, vitamin E, and vitamin C. Aged rats fed a diet supplemented with Korean red ginseng water extract had significantly less oxidative damage, possibly by enhancing the enzymatic and nonenzymatic antioxidants status. Our data suggest that consumption of Korean red ginseng reduces lipid peroxidation and restores antioxidant capacity by suppressing oxidative stress in rats.


Assuntos
Envelhecimento , Antioxidantes/análise , Suplementos Nutricionais , Estresse Oxidativo/efeitos dos fármacos , Panax/química , Extratos Vegetais/farmacologia , Animais , Ácido Ascórbico/farmacologia , Catalase/metabolismo , Dieta , Glutationa/farmacologia , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Vitamina E/farmacologia
7.
Exp Gerontol ; 47(12): 979-87, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23000874

RESUMO

Free radical-induced oxidative damage is considered to be the most important consequence of the aging process. The activities and capacities of antioxidant systems of cells decline with increased age, leading to the gradual loss of pro-oxidant/antioxidant balance and resulting in increased oxidative stress. Our investigation was focused on the effects of cordycepin (3'-deoxyadenosine) on lipid peroxidation and antioxidation in aged rats. Age-associated decline in the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), reduced glutathione (GSH), vitamin C and vitamin E, and elevated levels of malondialdehyde (MDA) were observed in the liver, kidneys, heart and lungs of aged rats, when compared to young rats. Furthermore, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, and creatinine were found to be significantly elevated in aged rats compared to young rats. Aged rats receiving cordycepin treatment show increased activity of SOD, CAT, GPx, GR and GST, and elevated levels of GSH, and vitamins C and E such that the values of most of these parameters did not differ significantly from those found in young rats. In addition, the levels of MDA, AST, ALT, urea and creatinine became reduced upon administration of cordycepin to aged rats. These results suggest that cordycepin is effective for restoring antioxidant status and decreasing lipid peroxidation in aged rats.


Assuntos
Envelhecimento/efeitos dos fármacos , Antioxidantes/farmacologia , Desoxiadenosinas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Envelhecimento/fisiologia , Animais , Ácido Ascórbico/metabolismo , Biomarcadores/sangue , Peso Corporal/efeitos dos fármacos , Catalase/metabolismo , Avaliação Pré-Clínica de Medicamentos , Ingestão de Alimentos/efeitos dos fármacos , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Vitamina E/metabolismo
8.
Planta Med ; 78(15): 1620-5, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22872590

RESUMO

This study was carried out to examine the potential beneficial effect of cordycepin on the decline of testicular function induced with age. A total of 30 male Sprague-Dawley rats (twenty-four 12-month-olds and six 2-month-olds) were divided into five groups. The young control (YC) and middle-aged control (MC) groups received vehicle only. Cordycepin-treated groups were administered daily doses of oral cordycepin at 5, 10, and 20 mg/kg body weight for 4 months. As a result, the MC group exhibited epididymal weight loss, decreased sperm motility, and reduced spermatogenesis compared to the young control group. Interestingly, the epididymal weights of middle-aged rats were dose-dependently increased by treatment with cordycepin. Cordycepin also improved calcium levels and decreased urea and nitrogen, uric acid, and creatinine in the blood of middle-aged rats. In addition, cordycepin significantly increased sperm motility and the progressiveness of sperm movement. All cordycepin-treated groups showed well-arranged spermatogonia, densely packed cellular material, and increased numbers of mature spermatozoa in the seminiferous lumen compared to the middle-aged control group. These results indicate that long-term administration of cordycepin can counteract the decline of testicular function in middle-aged rats.


Assuntos
Cordyceps/química , Desoxiadenosinas/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Desoxiadenosinas/química , Desoxiadenosinas/isolamento & purificação , Relação Dose-Resposta a Droga , Epididimo/efeitos dos fármacos , Fertilidade/efeitos dos fármacos , Hormônios Esteroides Gonadais/sangue , Humanos , Masculino , Estrutura Molecular , Micélio/química , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Contagem de Espermatozoides
9.
J Ginseng Res ; 35(3): 272-82, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23717070

RESUMO

Ginseng (Panax ginseng Meyer) has been shown to have anti-aging effects in animal and clinical studies. However, the molecular mechanisms by which ginseng exerts these effects remain unknown. Here, the anti-aging effect of Korean red ginseng (KRG) in rat testes was examined by system biology analysis. KRG water extract prepared in feed pellets was administered orally into 12 month old rats for 4 months, and gene expression in testes was determined by microarray analysis. Microarray analysis identified 33 genes that significantly changed. Compared to the 2 month old young rats, 13 genes (Rps9, Cyp11a1, RT1-A2, LOC365778, Sv2b, RGD1565959, RGD1304748, etc.) were up-regulated and 20 genes (RT1-Db1, Cldn5, Svs5, Degs1, Vdac3, Hbb, LOC684355, Svs5, Tmem97, Orai1, Insl3, LOC497959, etc.) were down-regulated by KRG in the older rats. Ingenuity Pathway Analysis of untreated aged rats versus aged rats treated with KRG showed that the affected most was Cyp11a1, responsible for C21-steroid hormone metabolism, and the top molecular and cellular functions are organ morphology and reproductive system development and function. When genes in young rat were compared with those in the aged rat, sperm capacitation related genes were down-regulated in the old rat. However, when genes in the old rat were compared with those in the old rat treated with KRG, KRG treatment up-regulated C21-steroid hormone metabolism. Taken together, Cyp11a1 expression is decreased in the aged rat, however, it is up-regulated by KRG suggesting that KRG seems enhance testes function via Cyp11a1.

10.
Phytother Res ; 22(6): 778-83, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18446850

RESUMO

Intake of Korean red ginseng (KRG, ginseng Radix rubra), rich in glycosylated saponins (ginsenosides), has been known to inhibit platelet aggregation in the normocholesterolemic condition. However, it is unclear whether KRG can attenuate hypercholesterolemia-enhanced platelet aggregation. This study examined whether the daily consumption of a KRG-water extract (WE) could prevent the hypercholesterolemia-enhanced platelet aggregation and progression of hypercholesterolemic atherosclerosis. KRG-WE administration (200 mg/kg/day) for 8 weeks potently inhibited the platelet aggregation induced by low doses of agonists (0.5 microg/mL collagen and 0.025 unit/mL thrombin), whereas it weakly reduced the blood-cholesterol levels and formation of atheromatous lesions. In further investigation, KRG-WE significantly suppressed collagen-induced 1,2-diacylglycerol liberation, but had no significant effect on arachidonic acid liberation. Taken together, it can be suggested that the antiplatelet effect of KRG-WE may, at least partly, be due to the inhibition of 1,2-diacylglycerol generation rather than regulation of blood lipid levels. In conclusion, daily consumption of KRG-WE could be a useful alternative measure for the prevention of thrombus and atheroma formation in hypercholesterolemia.


Assuntos
Diglicerídeos/metabolismo , Hipercolesterolemia/sangue , Panax/química , Agregação Plaquetária/efeitos dos fármacos , Animais , Ácido Araquidônico/metabolismo , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Colesterol na Dieta/administração & dosagem , Ginsenosídeos/análise , Ginsenosídeos/metabolismo , Hipercolesterolemia/induzido quimicamente , Coreia (Geográfico) , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Fosfolipídeos/metabolismo , Coelhos
11.
J Chromatogr A ; 1042(1-2): 163-8, 2004 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-15296401

RESUMO

This study was carried out to develop a cost-, labor- and efficiency-effective elimination method of pesticide residues in ginseng extract. A two-phase partition method between soybean oil and distilled water or aqueous ginseng extract was employed for the elimination of pesticide residues. Content of the pesticides was determined by gas chromatography with electron capture or nitrogen phosphorus detector. A total of 15 pesticides representing four categories (organochlorine, organophosphorus, carbamate, pyrethroid) were spiked (ca. 2 ppm) to 2 ml soybean oil in a test tube and the oil was mixed with 6 ml distilled water or 10% aqueous ginseng extract. The test tubes were then vortexed (2 min) and centrifuged at 3000 rpm for 15 min to separate the oil and aqueous layers. Each layer was harvested and subjected to quantitative analysis of pesticides. The average distribution ratio of the pesticides to the oil layer was 94.4 +/- 6.7% in the mixture of the oil and distilled water, and 105.5 +/- 6.6% in the mixture of the oil and ginseng extract. No significant qualitative and quantitative change of ginsenosides, the active ingredients of Panax ginseng, was observed in the ginseng extract before and after the oil treatment. These results suggest that two-phase partition chromatography between soybean oil and the aqueous phase is a cost-, labor- and efficiency-effective reliable method for the elimination of pesticide residues in ginseng extract.


Assuntos
Panax/química , Resíduos de Praguicidas/isolamento & purificação , Óleo de Soja/química , Fenômenos Químicos , Físico-Química , Cromatografia Líquida , Cromatografia em Camada Fina , Análise Custo-Benefício , Ácidos Graxos/análise , Ginsenosídeos/análise , Lipídeos/química , Extratos Vegetais/análise , Padrões de Referência
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