Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros

Base de dados
Tipo de documento
Assunto da revista
País de afiliação
Intervalo de ano de publicação
1.
J Nat Prod ; 78(11): 2588-97, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26562741

RESUMO

A polyamide column chromatography method using an aqueous ammonia mobile phase was developed for large-scale accumulation of water-soluble indoline amide glucosides from a medicinal plant, Portulaca oleracea. Ten new [oleraceins H, I, K, L, N, O, P, Q, R, S (1-10)] and four known [oleraceins A-D (11-14)] indoline amide glucosides were further purified and structurally characterized by various chromatographic and spectroscopic methods. The DPPH radical scavenging activities of oleraceins K (5) and L (6), with EC50 values of 15.30 and 16.13 µM, respectively, were twice that of a natural antioxidant, vitamin C; the EC50 values of the 12 other indoline amides, which ranged from 29.05 to 43.52 µM, were similar to that of vitamin C. Structure-activity relationships indicated that the DPPH radical scavenging activities of these indoline amides correlate with the numbers and positions of the phenolic hydroxy groups.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Compostos de Bifenilo/farmacologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Indóis/isolamento & purificação , Indóis/farmacologia , Fenóis/isolamento & purificação , Fenóis/farmacologia , Picratos/farmacologia , Plantas Medicinais/química , Portulaca/química , Alcaloides/química , Antioxidantes/química , Medicamentos de Ervas Chinesas/química , Sequestradores de Radicais Livres/química , Glucosídeos/química , Indóis/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Fenóis/química , Componentes Aéreos da Planta/química , Relação Estrutura-Atividade
2.
Pharm Biol ; 51(4): 455-62, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23336442

RESUMO

CONTEXT: Shaoyao Gancao Decoction (SGD), a famous herbal medicine, consists of two herbs (Paeoniae Radix and Glycyrrhizae Radix) and is traditionally used for the treatment of pain. OBJECTIVE: To investigate the synergistic potential of total glucosides of Paeoniae Radix (TGP) and total flavonoids of Glycyrrhizae Radix (TFL). MATERIALS AND METHODS: Oral administration of TGP and TFL alone at the doses of 60,120 and 240 mg/kg or in combination were given only one time to the neuropathic pain rat induced by chronic constriction injury. Paw pressure and heat immersion tests were performed to assess degrees of mechanical allodynia and thermal hyperalgesia, respectively. Synergistic interactions between TGP and TFL were characterized using isobolographic analysis. Expressions of Sirt1 protein were detected by immunohistochemistry. RESULTS AND DISCUSSION: On day 14 after surgery, single oral administration of TGP and TFL both produced significant anti-allodynic and anti-hyperalgesic effects in dose-dependent and time-dependent manners. The ED(50) value of TGP was 249.4 ± 10.8 mg/kg while TFL was 871.4 ± 30.5 mg/kg. Isobolographic analysis revealed that the combination of TGP with TFL at the fixed ratios of 3:1 exerted the highest sub-additive (synergistic) interaction, of which the experimental ED(50) value was 95.1 ± 9.0 mg/kg. SGD could also downregulate Sirt1 protein expression, which was 4.2-fold higher than that of model rats in dorsal root ganglion. CONCLUSION: Analgesic effects of SGD may contribute to simultaneous inhibition of Sirt1 overexpression and could warrant further evaluation as a possible agent for the treatment of neuropathic pain.


Assuntos
Analgésicos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Flavonoides/farmacologia , Glucosídeos/farmacologia , Glycyrrhiza , Hiperalgesia/prevenção & controle , Neuralgia/prevenção & controle , Paeonia , Administração Oral , Analgésicos/administração & dosagem , Analgésicos/isolamento & purificação , Animais , Comportamento Animal/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Sinergismo Farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/isolamento & purificação , Flavonoides/administração & dosagem , Flavonoides/isolamento & purificação , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Glucosídeos/administração & dosagem , Glucosídeos/isolamento & purificação , Glycyrrhiza/química , Hiperalgesia/etiologia , Hiperalgesia/fisiopatologia , Imuno-Histoquímica , Ligadura , Masculino , Neuralgia/etiologia , Neuralgia/fisiopatologia , Paeonia/química , Percepção da Dor/efeitos dos fármacos , Limiar da Dor/efeitos dos fármacos , Plantas Medicinais , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/cirurgia , Sirtuína 1/metabolismo , Fatores de Tempo
3.
Gene ; 554(2): 233-40, 2015 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-25311549

RESUMO

Type I polyketides are natural products with diverse functions that are important for medical and agricultural applications. Manipulation of large biosynthetic gene clusters containing type I polyketide synthases (PKS) for heterologous expression is difficult due to the existence of conservative sequences of PKS in multiple modules. Red/ET mediated recombination has permitted rapid manipulation of large fragments; however, it requires insertion of antibiotic selection marker in the cassette, raising the problem of interference of expression by leaving "scar" sequence. Here, we report a method for precise seamless stitching of large polyketide biosynthetic gene cluster using a 48.4kb fragment containing type I PKS involved in fostriecin biosynthesis as an example. rpsL counter-selection was used to assist seamless stitching of large fragments, where we have overcome both the size limitations and the restriction on endonuclease sites during the Red/ET recombination. The compatibility and stability of the co-existing vectors (p184 and pMT) which respectively accommodate 16kb and 32.4kb inserted fragments were demonstrated. The procedure described here is efficient for manipulation of large DNA fragments for heterologous expression.


Assuntos
Clonagem Molecular/métodos , Escherichia coli/genética , Escherichia coli/metabolismo , Plasmídeos/genética , Policetídeo Sintases/genética , Escherichia coli/enzimologia , Proteínas de Escherichia coli/genética , Vetores Genéticos , Família Multigênica , Policetídeo Sintases/metabolismo , Recombinação Genética , Proteína S9 Ribossômica , Proteínas Ribossômicas/genética , Análise de Sequência de DNA
4.
J Pharm Anal ; 2(2): 83-89, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29403726

RESUMO

This paper sets out to summarize the literatures based on immobilized enzyme bio-chromatography and its application in inhibitors screening in the last decade. In order to screen enzyme inhibitors from a mass of compounds in preliminary screening, multi-pore materials with good biocompatibility are used for the supports of immobilizing enzymes, and then the immobilized enzyme reactor applied as the immobilized enzyme stationary phase in HPLC. Therefore, a technology platform of high throughput screening is gradually established to screen the enzyme inhibitors as new anti-tumor drugs. Here, we briefly summarize the selective methods of supports, immobilization techniques, co-immobilized enzymes system and the screening model.

5.
Dermatology ; 213(3): 218-23, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17033171

RESUMO

BACKGROUND: Genital warts are a common sexually transmitted disease caused by human papillomaviruses. Podophyllotoxin 0.5%, approved for patient self-administration, has been used most extensively in the treatment of genital warts. Imiquimod, a novel immune response modifier capable of inducing interferon-alpha and a variety of cytokines, has been examined as a potential treatment for genital warts. But 0.5% podophyllotoxin and 5% imiquimod have not been compared in any extensive and formal studies, although they are the common topical agents for genital warts. OBJECTIVE: To evaluate the efficacy and safety of topical 5% imiquimod and 0.5% podophyllotoxin in the treatment of genital warts. METHODS: We searched Medline (1966 to June 2005), Embase (1974 to June 2005) and the Cochrane Controlled Trials Register (issue 3, 2005). Randomized controlled trials of 5% imiquimod or 0.5% podophyllotoxin in the treatment of genital warts were collected. Two reviewers extracted the data and independently assessed the quality of the included medical literature. Then, meta-analysis was conducted. RESULTS: Twelve studies including 3 placebo-controlled trials of imiquimod and 9 placebo-controlled trials of podophyllotoxin were included. The clinical cure rates of imiquimod and podophyllotoxin were 50.34 and 56.41%, respectively, without statistically significant differences between the two (p > 0.05). A combined analysis of the 3 studies on imiquimod showed a statistically significant difference to the placebo group [pooled odds ratio (OR) 11.65, 95% confidence interval (CI) 6.05-22.44], as did a combined analysis of the 9 studies on podophyllotoxin (pooled OR 16.70, 95% CI 7.06-39.48). The most common adverse events of imiquimod were erythema, erosion, excoriation, itching and burning; those of podophyllotoxin were burning, pain, erosion, itching and inflammation. CONCLUSION: Imiquimod and podophyllotoxin possess similar curative effects on condylomata acuminata but podophyllotoxin has more serious adverse effects.


Assuntos
Aminoquinolinas/uso terapêutico , Antineoplásicos/uso terapêutico , Condiloma Acuminado/tratamento farmacológico , Ceratolíticos/uso terapêutico , Podofilotoxina/uso terapêutico , Bases de Dados Factuais , Humanos , Imiquimode , Ensaios Clínicos Controlados Aleatórios como Assunto
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA