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1.
Nat Prod Res ; 35(7): 1167-1171, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31339381

RESUMO

Chemical investigation of the lichen Dirinaria applanata led to isolate nine compounds including a new hopane derivative, 1ß-acetoxy-21α-hopane-3ß,22-diol (1) together with six phenolic compounds naming divaricatinic acid (2), methyl divaricatinate (3), methyl-ß-orcinolcarboxylate (4), methyl haematommate (5), divarinol (6), ramalinic acid A (7), and two xanthones namely lichenxanthone (8), 4,5-dichlorolichenxanthone (9). Their structures were elucidated by spectroscopic data in combination with published literature. Except compound 2, all compounds were isolated from this species for the first time.


Assuntos
Ascomicetos/química , Triterpenos/isolamento & purificação , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Estereoisomerismo , Triterpenos/química
2.
Int J Anal Chem ; 2020: 8862679, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33293960

RESUMO

A liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method has been validated for the simultaneous determination of methamphetamine (MA) and 3,4-methylenedioxy-N-methamphetamine (MDMA) in the blood sample. Under the optimal experimental conditions, the concentration of MA can be determined in the range from 1 µg/L to 5000 µg/L with the method detection limit (MDL) of 0.31 µg/L. The range from 0.5 to 500 µg/L is observed for the determination of MDMA with the MDL down to 0.25 µg/L. The practical applicability of the method is performed with the recovery ranging from 85.3% to 94% for MA and from 86.9% to 95.5% for MDMA. At the different concentrations of drugs, the relative standard deviations (RSD) for both MA and MDMA are lower than 5.7%. The method was applied to analyse 1995 blood samples that had been collected from the Forensic Medicine Centre of Ho Chi Minh City. The results showed 1.75% positive with MA and 0.25% positive with MDMA. These two drugs take 10% of the total drugs positive samples. By using deuterium-labelled methamphetamine-d5 and 3,4-methylenedioxy-N-methamphetamine-d5 as the internal standards in the determination and the use of MS/MS in multiple reaction monitoring mode signal readout, the method exhibits robustness specificity and can be applied in simultaneous determination of MA and MDMA in blood with high selectivity and sensitivity.

3.
Nutrients ; 12(9)2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32858855

RESUMO

Launaea sarmentosa has been extensively used as a nutrient herb in traditional Vietnamese remedies for the treatment of various diseases, especially inflammatory diseases. However, no detailed research has been conducted examining the molecular mechanisms involved in the suppression of inflammatory response. Here, we studied the effects of L. sarmentosa methanol extract on lipopolysaccharide (LPS)-induced inflammation using RAW 264.7 macrophages. The extract demonstrated potent antioxidant activity owing to the presence of polyphenolic and flavonoid components. Pretreatment with the extract inhibited LPS-mediated secretion of nitric oxide, reactive oxygen species, and tumor necrosis factor-α as well as the expression of inflammatory cytokines. Furthermore, the activation of the nuclear factor-kappa B pathway and phosphoinositide-3-kinase/protein kinase B pathways was blocked by the extract by inhibiting Akt phosphorylation. Additionally, the mitogen-activated protein kinase pathway was suppressed, and endoplasmic reticulum stress was attenuated. Furthermore, the extract promoted the activity of nuclear factor erythroid-2-related factor 2 resulting in the up-regulation of heme oxygenase-1 pathway, leading to the suppression of oxidative stress and inflammatory response. Taken together, the results indicate that L. sarmentosa exhibits anti-inflammatory effects, and hence, can be further developed as a novel drug for the treatment of diseases associated with excessive inflammation.


Assuntos
Anti-Inflamatórios/farmacologia , Inflamação/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Medicina Tradicional , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , NF-kappa B/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Lipopolissacarídeos , Camundongos , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos
4.
Int J Mol Sci ; 21(10)2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32414062

RESUMO

Lasia spinosa (L.) Thwaites was used as a traditional medicine to treat many inflammatory diseases for centuries. However, its effects on the inflammatory response are not yet characterized. In this study, we investigated the anti-inflammatory activities of L. spinosa leaf extract in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. We found that ethanol extracts of L. spinosa leaves showed anti-oxidant activity due to the presence of high levels of polyphenolic compounds. Treatment with the leaf extract significantly repressed the production of inflammatory mediators such as nitric oxide and reactive oxygen species and the expression of pro-inflammatory cytokines in the LPS-stimulated RAW 264.7 cells. Moreover, L. spinosa leaf extract treatment prevented activation of the nuclear factor-kappa B pathway by inhibiting nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) degradation. Furthermore, the mitogen-activated kinase and phosphoinositide-3-kinase/protein kinase B (PI3K/Akt) pathways were suppressed upon treatment with the leaf extract. In addition to suppressing inflammatory factors, the extract also activated the nuclear factor erythroid 2-related factor 2/heme-oxygenase-1 pathway. We propose that L. spinosa leaf extract has the potential as an effective therapeutic agent for alleviating oxidative stress and excessive inflammation.


Assuntos
Araceae/química , Inflamação/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Extratos Vegetais/química , Animais , Humanos , Inflamação/induzido quimicamente , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Camundongos , NF-kappa B/genética , Extratos Vegetais/farmacologia , Folhas de Planta/química , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos
5.
Polymers (Basel) ; 11(1)2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30960161

RESUMO

In this study, chitosan nanoparticles were used as a carrier for Protocatechuic acid (PCA) to resist Pyricularia oryzae against rice blast. The final compound was characterized using zeta potentials for its surface electricity, Fourier transform infrared (FT-IR) analysis and transmission electron microscopy (TEM) were conducted for functional groups and for particle sizes and shape, respectively. The zeta potential results showed that loading PCA causes chitosan nanoparticle (CSNP) to decrease in surface electrons. The TEM images revealed that the particle size of chitosan (CS), although increasing in size when carrying PCA molecules, showed sufficient size for reasonable penetration into fungal cells. The FT-IR analysis showed that all functional group in CSNP carried PCA matched with previous studies. The antifungal test showed that diameters of inhibition zone of CS increases significantly after loading PCA, exhibiting the strongest antimicrobial effect on the Pyricularia oryzae fungus compared with weaker effects exhibited by CSNP alone or PCA. Our results suggested that CSNP loaded with PCA could be a potential compound for eradication of Pyricularia oryzae and that further testing on in vitro rice plants is recommended to reaffirm this possibility.

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