Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Environ Pollut ; 333: 122099, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37356791

RESUMO

This research explores the influence of renewable fuels, including three kinds of biodiesel along with ethanol on the physical properties and structural characteristics of particulate matter (PM) emitted from a diesel engine in comparison with pure diesel. After adding 10 vol% of grape seed biodiesel, coffee biodiesel and eucalyptus oil into diesel, three biodiesel blended fuels (10% grape seed biodiesel (DGs10), 10% spent coffee ground biodiesel (DC10) and eucalyptus oil biodiesel (DEu10)) were produced and tested in this study. Besides, one ethanol blend containing 9 vol% of ethanol and 1 vol% of biodiesel (blend stabilizer) was also tested to do the comparison. In the present study, scanning transmission electron microscope (STEM) and scanning electron microscope (SEM) were employed for analyzing the microstructure, nanostructure and electron diffraction pattern of PM. Raman spectrometer (RS) was also used for the analysis of structural characterization of PM. In addition, several experimental instruments like microbalance, measuring cup, viscometer, oxygen bomb calorimeter and Gas Chromatography-Mass Spectrometer (GC-MS) were employed to detect the fuel properties, including density, heating value, viscosity, composition and cetane number. A conclusion can be drawn that both biodiesel blends and ethanol blend have a changing effect on the PM properties compared to pure diesel, where biodiesel blends have a slightly weaker influence than ethanol blend. Regarding the biodiesel blends, DGs10 has more impact than DC10 and DEu10 in changes of PM properties, particularly in the reduction of PM mass, making it a good candidate for renewable fuel for diesel engines.


Assuntos
Biocombustíveis , Material Particulado , Material Particulado/análise , Biocombustíveis/análise , Gasolina/análise , Emissões de Veículos/análise , Óleo de Eucalipto , Café , Etanol
2.
J Ethnopharmacol ; 170: 8-15, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-25934514

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The fruit of Schisandra chinensis (Turcz.) Baill, has been traditionally used in management of liver diseases and ageing associated neurodegeneration. The bioactive compound from this medicinal plant would be valuable for its potential use in prevention and treatment of Parkinson׳s disease. AIM OF THE STUDY: The overall objective of the present study was to understand the neuroprotective effect of schisantherin A, a dibenzocyclooctadiene lignan from the fruit of S. chinensis (Turcz.) Baill, and to elucidate its underlying mechanism of action. MATERIAL AND METHODS: This study investigated the protective effect of schisantherin A against selective dopaminergic neurotoxin 6-hydroxydopamine (6-OHDA)-induced neural damage in human neuroblastoma SH-SY5Y cells and zebrafish models. Oxidative stress and related signaling pathways underlying the neuroprotective effect were determined by multiple biochemical assays and Western blot. RESULTS: Pretreatment with schisantherin A offered neuroprotection against 6-OHDA-induced SH-SY5Y cytotoxicity. Moreover, schisantherin A could prevent 6-OHDA-stimulated dopaminergic neuron loss in zebrafish. Our mechanistic study showed that schisantherin A can regulate intracellular ROS accumulation, and inhibit NO overproduction by down-regulating the over-expression of iNOS in 6-OHDA treated SH-SY5Y cells. Schisantherin A also protects against 6-OHDA-mediated activation of MAPKs, PI3K/Akt and GSK3ß. CONCLUSION: These findings demonstrate that schisantherin A may have potential therapeutic value for neurodegenerative diseases associated with abnormal oxidative stress such as Parkinson׳s disease.


Assuntos
Ciclo-Octanos/farmacologia , Dioxóis/farmacologia , Neurônios Dopaminérgicos/efeitos dos fármacos , Lignanas/farmacologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Antiparkinsonianos/isolamento & purificação , Antiparkinsonianos/farmacologia , Linhagem Celular Tumoral , Ciclo-Octanos/isolamento & purificação , Dioxóis/isolamento & purificação , Neurônios Dopaminérgicos/patologia , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Lignanas/isolamento & purificação , Neuroblastoma/metabolismo , Fármacos Neuroprotetores/isolamento & purificação , Óxido Nítrico/metabolismo , Oxidopamina/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Schisandra/química , Transdução de Sinais/efeitos dos fármacos , Peixe-Zebra
3.
Free Radic Biol Med ; 84: 331-343, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25769424

RESUMO

Polypharmacology-based strategies using drug combinations with different mechanisms of action are gaining increasing attention as a novel methodology to discover potentially innovative medicines for neurodegenerative disorders. We used this approach to examine the combined neuroprotective effects of two polyphenols, protocatechuic acid (PCA) and chrysin, identified from the fruits of Alpinia oxyphylla. Our results demonstrated synergistic neuroprotective effects, with chrysin enhancing the protective effects of PCA, resulting in greater cell viability and decreased lactate dehydrogenase release from 6-hydroxydopamine-treated PC12 cells. Their combination also significantly attenuated chemically induced dopaminergic neuron loss in both zebrafish and mice. We examined the molecular mechanisms underlying these collective cytoprotective effects through proteomic analysis of treated PC12 cells, resulting in the identification of 12 regulated proteins. Two were further characterized, leading to the determination that pretreatment with PCA and chrysin resulted in (i) increased nuclear factor-erythroid 2-related factor 2 protein expression and transcriptional activity; (ii) modulation of cellular redox status with the upregulated expression of hallmark antioxidant enzymes, including heme oxygenase-1, superoxide dismutase, and catalase; and (iii) decreased levels of malondialdehyde, a known lipid peroxidation product. Treatment with PCA and chrysin also inhibited activation of nuclear factor-κB and expression of inducible nitric oxide synthase. Our findings suggest that natural products, when used in combination, can be effective potential therapeutic agents for treating diseases such as Parkinson disease. A therapy involving both PCA and chrysin exhibits its enhanced neuroprotective effects through a combination of cellular mechanisms: antioxidant cytoprotection and anti-inflammation.


Assuntos
Antiparkinsonianos/farmacologia , Flavonoides/farmacologia , Hidroxibenzoatos/farmacologia , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson/tratamento farmacológico , Animais , Antiparkinsonianos/uso terapêutico , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/fisiologia , Avaliação Pré-Clínica de Medicamentos , Flavonoides/uso terapêutico , Heme Oxigenase-1/metabolismo , Hidroxibenzoatos/uso terapêutico , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo , Células PC12 , Proteoma/metabolismo , Proteômica , Ratos , Fator de Transcrição RelA/metabolismo , Peixe-Zebra
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA