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1.
Chem Biodivers ; 17(7): e2000121, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32374938

RESUMO

Carpodesmia tamariscifolia is a brown alga rich in (poly)phenols with important cytotoxic and antioxidant effects. However, the relationship between its chemical composition and its effects is unknown. The aim of this study is to identify the potential compounds and mechanisms responsible for its main effects. The alga was extracted consecutively with hexane, dichloromethane and methanol and further fractionated using Sephadex LH-20 and silica gel columns when appropriate. The fractions were subjected to thin-layer chromatography and liquid chromatography-mass spectrometry analysis and evaluated for their total phenolic content (Folin-Ciocalteu assay), radical scavenging activity (DPPH assay), cytotoxic activity (MTT assay on the SH-SY5Y cell line), and ability to generate H2 O2 (Amplex Red assay). Chromatographic and phenolic analyses of the fractions indicate that abundant redox-active phenols are present in all the fractions and that a high amount of prenylated hydroquinone derivatives is present in the apolar ones. In the hexane and dichloromethane fractions, the cytotoxic and antioxidant activities are closely related to their phenolic content, whereas in the methanol fractions, the cytotoxicity is negatively related to the phenolic content and the antioxidant activity is positively related to it. In the same tests, hydroquinone behaves as both strong cytotoxic and antioxidant agent. H2 O2 assay shows that C. tamariscifolia fractions and hydroquinone can autoxidize and generate H2 O2 . Our results suggest that redox-active phenols produce the pharmacological effects described for C. tamariscifolia and that the hydroquinone moiety of prenylated hydroquinone derivatives is responsible for both cytotoxic (through a pro-oxidant mechanism secondary to its autoxidation) and antioxidant effects of the apolar fractions.


Assuntos
Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Fenóis/farmacologia , Alga Marinha/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Oxirredução , Fenóis/química , Fenóis/isolamento & purificação , Picratos/antagonistas & inibidores , Relação Estrutura-Atividade , Células Tumorais Cultivadas
2.
Int J Biometeorol ; 59(3): 339-46, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24844880

RESUMO

Alternaria is frequently found as airborne fungal spores and is recognized as an important cause of respiratory allergies. The aerobiological monitoring of fungal spores was performed using a Burkard volumetric spore traps. To establish predicting variables for daily and weakly spore counts, a stepwise multiple regression between spore concentrations and independent variables (meteorological parameters and lagged values from the series of spore concentrations: previous day or week concentration (Alt t - 1) and mean concentration of the same day or week in other years (C mean)) was made with data obtained during 2009-2011. Alternaria conidia are present throughout the year in the atmosphere of Tetouan, although they show important seasonal fluctuations. The highest levels of Alternaria spores were recorded during the spring and summer or autumn. Alternaria showed maximum daily values in April, May or October depending on year. When the spore variables of Alternaria, namely C mean and Alt t - 1, and meteorological parameters were included in the equation, the resulting R (2) satisfactorily predict future concentrations for 55.5 to 81.6 % during the main spore season and the pre-peak 2. In the predictive model using weekly values, the adjusted R (2) varied from 0.655 to 0.676. The Wilcoxon test was used to compare the results from the expected values and the pre-peak spore data or weekly values for 2012, indicating that there were no significant differences between series compared. This test showed the C mean, Alt t - 1, frequency of the wind third quadrant, maximum wind speed and minimum relative humidity as the most efficient independent variables to forecast the overall trend of this spore in the air.


Assuntos
Poluentes Atmosféricos/isolamento & purificação , Alternaria , Modelos Teóricos , Esporos Fúngicos/isolamento & purificação , Microbiologia do Ar , Contagem de Colônia Microbiana , Monitoramento Ambiental/estatística & dados numéricos , Previsões , Marrocos , Análise de Regressão , Estações do Ano , Tempo (Meteorologia)
3.
Int J Biometeorol ; 57(2): 197-205, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22744802

RESUMO

Poaceae pollen is one of the most prevalent aeroallergens causing allergenic reactions. The aim of this study was to characterise the grass pollen season in Tetouan during the years 2008-2010, to analyse the effect of some meteorological parameters on the incidence of the airborne Poaceae pollen, and to establish forecasting variables for daily pollen concentrations. Aerobiological sampling was undertaken over three seasons using the volumetric method. The pollen season started in April and showed the highest pollen index in May and June, when the maximum temperature ranged from 23 to 27 °C, respectively. The annual pollen score recorded varied from year to year between 2,588 and 5,404. The main pollen season lasted 114-173 days, with peak days occurring mainly in May; the highest concentration reached 308 pollen grains/m(3). Air temperature was the most important meteorological parameter and correlated positively to daily pollen concentration increase. An increase in relative humidity and precipitation was usually related to a decrease in airborne pollen content. External validation of the models performed using data from 2011 showed that Poaceae pollen concentration can be highly predicted (64.2-78.6 %) from the maximum temperature, its mean concentration for the same day in other years, and its concentration recorded on the previous day. Sensitive patients suffering allergy to Poaceae pollen are at moderate to highest risk of manifesting allergic symptoms to grass pollen over 33-42 days. The results obtained provide new information on the quantitative contribution of the Poaceae pollen to the airborne pollen of Tetouan and on its temporal distribution. Airborne pollen can be surveyed and forecast in order to warn the atopic population.


Assuntos
Alérgenos/análise , Poaceae , Pólen , Atmosfera , Cidades , Marrocos , Tempo (Meteorologia)
4.
Mar Drugs ; 9(7): 1187-1209, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21822410

RESUMO

Water-soluble sulfated polysaccharides isolated from two red algae Sphaerococcus coronopifolius (Gigartinales, Sphaerococcaceae) and Boergeseniella thuyoides (Ceramiales, Rhodomelaceae) collected on the coast of Morocco inhibited in vitro replication of the Human Immunodeficiency Virus (HIV) at 12.5 µg/mL. In addition, polysaccharides were capable of inhibiting the in vitro replication of Herpes simplex virus type 1 (HSV-1) on Vero cells values of EC50 of 4.1 and 17.2 µg/mL, respectively. The adsorption step of HSV-1 to the host cell seems to be the specific target for polysaccharide action. While for HIV-1, these results suggest a direct inhibitory effect on HIV-1 replication by controlling the appearance of the new generations of virus and potential virucidal effect. The polysaccharides from S. coronopifolius (PSC) and B. thuyoides (PBT) were composed of galactose, 3,6-anhydrogalactose, uronics acids, sulfate in ratios of 33.1, 11.0, 7.7 and 24.0% (w/w) and 25.4, 16.0, 3.2, 7.6% (w/w), respectively.


Assuntos
Antivirais/farmacologia , Polissacarídeos/farmacologia , Rodófitas/química , Adsorção/efeitos dos fármacos , Animais , Antivirais/análise , Antivirais/química , Antivirais/isolamento & purificação , Sobrevivência Celular , Chlorocebus aethiops , Galactose/análogos & derivados , Galactose/química , Galactose/farmacologia , HIV-1/efeitos dos fármacos , Herpesvirus Humano 1/efeitos dos fármacos , Humanos , Metaloproteinase 17 da Matriz/efeitos dos fármacos , Peso Molecular , Marrocos , Oceanos e Mares , Fitoterapia , Preparações de Plantas/farmacologia , Polissacarídeos/análise , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Sulfatos/química , Sulfatos/farmacologia , Fatores de Tempo , Ácidos Urônicos/química , Ácidos Urônicos/farmacologia , Células Vero , Replicação Viral/efeitos dos fármacos
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