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1.
J Cosmet Sci ; 57(4): 279-89, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16957808

RESUMO

Matrix metalloproteinases (MMPs) are known to play an important role in photoaging by mediating the degradation of extracellular matrix proteins. To develop a new anti-aging agent for cosmetics from natural products, Melothria heterophylla (Lour.) Cogn. was selected for its antioxidant activity and inhibitory effect on expression of MMP-1 in UVA-irradiated human skin fibroblasts. Two compounds (compounds 1 and 2 ) were isolated from an ethyl acetate soluble fraction of the ethanolic extracts; they were identified as 1,2,4,6-tetra-O-galloyl-beta-(D)-glucopyranose (1) and 3,4,5-trihydroxybenzoic acid (2). These compounds were found to scavenge radicals and reactive oxygen species (ROS) and were measured to have SC50 values of 3.9 microM and 13.3 microM against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and values of 4.3 microM and 4.0 microM against superoxide radicals in the xanthine/xanthine oxidase system, respectively. Compounds 1 and 2 showed a dose-dependent inhibitory effect on the expression and activity of MMP-1 in UVA-induced human skin fibroblasts, but no inhibition of MMP-1 mRNA expression. Therefore, we concluded that compounds 1 and 2 significantly inhibited MMP-1 expression at the protein level. Also, these compounds were determined to have a potent antioxidant activity. From these results, we suggest that these compounds might be useful as a new anti-aging agent for photodamaged skin, but the in vitro findings must be verified in in vivo studies.


Assuntos
Antioxidantes/farmacologia , Cucurbitaceae/química , Ácido Gálico/farmacologia , Glucose/análogos & derivados , Inibidores de Metaloproteinases de Matriz , Pele/efeitos dos fármacos , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/química , Ensaio de Imunoadsorção Enzimática , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Fibroblastos/efeitos da radiação , Ácido Gálico/química , Ácido Gálico/isolamento & purificação , Glucose/química , Glucose/farmacologia , Humanos , Hidrazinas/química , Metaloproteinase 1 da Matriz/biossíntese , Metaloproteinase 1 da Matriz/genética , Ressonância Magnética Nuclear Biomolecular , Picratos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Raízes de Plantas/química , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Pele/enzimologia , Pele/efeitos da radiação , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Ultravioleta , Superóxidos/química
2.
J Cosmet Sci ; 57(1): 11-21, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16676120

RESUMO

To develop a new whitening agent for cosmetics from natural products, Angelica dahurica was selected for its inhibitory effect on melanogenesis in B16 melanoma cells. From the mechanism study, it was clarified that the ethanolic extracts of this plant showed the suppression of tyrosinase synthesis but no inhibition of tyrosinase activity. In order to find the active constituents from this plant, the ethanol extracts were chromatographed repeatedly with silica gel. Two coumarin compounds were isolated from A. dahurica. Their structures were identified by physicochemical and spectral data such as UV, IR, NMR, and MS. It was shown that the active substance was isoimperatorin (10-[(3-methyl-2-butenyl)oxy]-7H-furo[3,2-g][1] benzopyran-7-one) and imperatorin (9-[(3-methyl-2-butenyl)oxy]-7H-furo[3,2-g][1] benzopyran-7-one). They significantly inhibited tyrosinase synthesis in B16 melanoma cells. To elucidate the action mechanism of the active compounds of A. dahurica, we investigated the changes in the mRNA level of tyrosinase using the RT-PCR technique. As a result, the mRNA level of tyrosinase was markedly reduced by active compounds of A. dahurica. From these results, we suggest that these extracts might be useful as a new whitening agent in cosmetics, but the in vitro findings must be verified in in vivo skin-lightening studies.


Assuntos
Angelica/química , Cosméticos , Extratos Vegetais/farmacologia , Pigmentação da Pele/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Furocumarinas/química , Furocumarinas/isolamento & purificação , Expressão Gênica/efeitos dos fármacos , Humanos , Melaninas/antagonistas & inibidores , Melaninas/biossíntese , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/enzimologia , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Camundongos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/biossíntese , Monofenol Mono-Oxigenase/genética , Monofenol Mono-Oxigenase/metabolismo , Extratos Vegetais/química , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
J Chromatogr A ; 912(1): 119-25, 2001 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-11307974

RESUMO

A new technique is proposed for the determination of bisphenol A in environmental water. The sample preparation consists of a single-step extraction of bisphenol A from a water sample with methylene chloride and the cyanomethyl derivatization of bisphenol A. 2,2'-Biphenol is used as an internal standard. Bisphenol A and biphenol can be quantitatively converted to their corresponding cyanomethyl ethers, which are then measured by gas chromatography with nitrogen-phosphorus detection. Peak shape and quantification of bisphenol A are excellent, with linear calibration curves over a range of 0.1-100 ng/ml. The detection limit is 0.1 ng/ml in water samples. The average recovery and RSD at a concentration of 5 ng/ml are 89.3 and 4.5%, respectively. The procedure is applicable to the quantification of bisphenol A in tap water, raw water and stream water.


Assuntos
Cromatografia Gasosa/métodos , Fenóis/análise , Poluentes Químicos da Água/análise , Compostos Benzidrílicos , Calibragem , Espectrometria de Massas , Metilação , Estrutura Molecular , Nitrogênio , Fenóis/química , Fósforo , Reprodutibilidade dos Testes
4.
Am J Clin Oncol ; 23(3): 301-8, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10857899

RESUMO

A matched-control study comparing standard radiotherapy versus neoadjuvant chemotherapy and radiation was undertaken to clarify the effects of neoadjuvant systemic chemotherapy for locally advanced squamous cell carcinoma of the maxillary antrum. Thirty-four patients with inoperable maxillary cancer were treated with neoadjuvant chemotherapy and radiotherapy (Group II). Before starting radiotherapy, all patients in Group II received two or three cycles of neoadjuvant chemotherapy consisting of cisplatin and a 5-day continuous infusion of 5-fluorouracil with or without intravenous injection of vinblastine. Radiation doses ranged from 66 Gy to 75 Gy (median, 70 Gy). The response rate, patterns of failure, toxicity, and survival for Group II were compared with those for 34 stage-matched patients treated with radiation alone (Group I). Despite a higher response rate to neoadjuvant chemotherapy, the recurrence rate and patterns of treatment failure were not influenced by the addition of neoadjuvant chemotherapy. In most cases, neoadjuvant chemotherapy did not interfere with subsequent radiotherapy, and radiation-induced late complications occurred equally in both treatment groups. After a median follow-up of 48 months, there was no significant difference in 5-year actuarial survival or disease-free survival between the two treatment groups. Radiation alone for inoperable maxillary cancer was clearly suboptimal for improving local control and survival rate, but neoadjuvant chemotherapy in addition to standard radiotherapy failed to demonstrate any therapeutic advantage over radiation alone.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias do Seio Maxilar/tratamento farmacológico , Neoplasias do Seio Maxilar/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Estudos de Casos e Controles , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Terapia Combinada , Feminino , Fluoruracila/administração & dosagem , Humanos , Masculino , Neoplasias do Seio Maxilar/mortalidade , Pessoa de Meia-Idade , Falha de Tratamento
5.
Am J Kidney Dis ; 25(1): 58-62, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7810534

RESUMO

Nephrotic syndrome is characterized by water and sodium retention, which leads to edema formation. The nonosmotic stimulation of arginine vasopressin (AVP) release from the pituitary gland has been implicated to be one of the important factors of abnormal water retention in patients with nephrotic syndrome. It is not known, however, whether nephrotic syndrome is associated with stimulation of hypothalamic vasopressin gene expression. Puromycin aminonucleoside is known to cause altered glomerular permeability, which results in experimental nephrotic syndrome in rats. In the present study, therefore, AVP gene expression has been studied in the hypothalamus of rats with puromycin aminonucleoside-induced nephrotic syndrome (PNS). Nephrotic syndrome was induced by a single intravenous injection of puromycin aminonucleoside (50 mg/kg body weight). Nephrotic syndrome was confirmed by urinary protein excretion (control 20.8 +/- 3.5 mg/24 hr v PNS 273.9 +/- 41.4 mg/24 hr; P < 0.0001, n = 6) and serum albumin concentrations (control 4.52 +/- 0.07 g/dL v PNS 2.96 +/- 0.22 g/dL; P < 0.001, n = 6). In PNS rats, plasma AVP was significantly higher than in control rats (control 0.77 +/- 0.10 pg/mL v PNS 2.13 +/- 0.42 pg/mL; P < 0.005, n = 12), even though there were no differences in plasma osmolality (control 292.0 +/- 2.0 mOsm/kg H2O v PNS 290.3 +/- 2.5 mOsm/kg H2O; P = NS, n = 12) or serum sodium concentration (control 142.7 +/- 0.7 v PNS 142.1 +/- 1.1; PNS, n = 12).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Arginina Vasopressina/biossíntese , Hipotálamo/metabolismo , Síndrome Nefrótica/metabolismo , Animais , Arginina Vasopressina/genética , Expressão Gênica , Masculino , Síndrome Nefrótica/sangue , Síndrome Nefrótica/induzido quimicamente , Síndrome Nefrótica/urina , Puromicina Aminonucleosídeo , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Vasopressinas/sangue
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