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1.
Nat Prod Commun ; 5(3): 365-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20420308

RESUMO

The crude ethanolic extract of leaves, stem-bark and roots of J. flammea were tested for their cytotoxic effect against two mammalian cell lines (HeLa and RAW 264.7) and four bacterial species (Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa). When tested at the concentration of 100 microg/mL, the root extract showed the highest cytotoxic activity against mammalian cells followed by the stem-bark extract while the leaves extract did not show significant activity. No antibacterial activity was detected for all extracts when tested up to 500 microg/disc in the disc diffusion assay. The cytotoxic root extract was subjected to fractionation using solvents of ascending polarity: petroleum ether, chloroform, ethylacetate, butanol and water. The water fraction which showed cytotoxic activity was further subjected to routine bioassay-guided fraction to lead to the isolation of sakurasosaponin as the active principle. The recorded IC50 value for sakurasosaponin was 11.3 +/- 1.52 and 3.8 +/- 0.25 microM (n=3) against HeLa and RAW 264.7 respectively. The identification of sakurasosaponin was based on analysis of spectroscopic data.


Assuntos
Antibacterianos/química , Antibacterianos/toxicidade , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/toxicidade , Plantas Medicinais/química , Saponinas/química , Saponinas/toxicidade , Animais , Bactérias/efeitos dos fármacos , Sequência de Carboidratos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Metanol , México , Camundongos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Raízes de Plantas/química , Solventes
2.
Tuberculosis (Edinb) ; 89(4): 267-77, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19493698

RESUMO

Tuberculosis has been a scourge of humans over many millennia, but questions remain regarding its evolution and epidemiology. Fossil biomarkers, such as DNA and long-chain mycolic acids, can be detected in ancient skeletal and other materials. The phthiocerol dimycocerosate waxes are also robust biomarkers for tuberculosis and sensitive methods are available for the detection of their mycocerosic acid components. The presence of mycocerosic acids was investigated in 49 individuals from the 1837-1936 Coimbra Identified Skeletal Collection (Portugal), half with documentary data indicating tuberculosis as a cause of death. Samples were hydrolysed, acidic components converted to pentafluorobenzyl esters, the non-hydroxylated long-chain esters isolated, and this fraction separated into multimethyl-branched and other esters by normal phase high performance liquid chromatography. Negative ion chemical ionisation gas chromatography mass spectrometry was used to detect diagnostic C29, C30 and C32 mycocerosic acids. Mycocerosic acids were detected in archaeological material for the first time, illustrating that they are valuable biomarkers for the diagnosis of ancient tuberculosis. A 72% correlation with the Coimbra burial record supported TB as the major cause of death. In addition, 30% of the skeletons, positive for mycocerosates, showed the presence of related long-chain mycolipenic acids.


Assuntos
Ácidos Graxos/análise , Costelas/química , Tuberculose/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Biomarcadores/química , Cadáver , Criança , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Ácidos Graxos/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/química , Portugal , Adulto Jovem
3.
Phytochemistry ; 70(6): 765-72, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19394983

RESUMO

Evaluation of the cytotoxicity of an ethanolic root extract of Sideroxylonfoetidissimum subsp. gaumeri (Sapotaceae) revealed activity against the murine macrophage-like cell line RAW 264.7. Systematic bioassay-guided fractionation of this extract gave an active saponin-containing fraction from which four saponins were isolated. Use of 1D ((1)H, (13)C, DEPT135) and 2D (COSY, TOCSY, HSQC, and HMBC) NMR, mass spectrometry and sugar analysis gave their structures as 3-O-(beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl)-28-O-(alpha-L-rhamnopyranosyl-(1-->3)[beta-D-xylopyranosyl-(1-->4)]-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl)-16alpha-hydroxyprotobassic acid, 3-O-beta-D-glucopyranosyl-28-O-(alpha-L-rhamnopyranosyl-(1-->3)[beta-D-xylopyranosyl-(1-->4)]-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl)-16alpha-hydroxyprotobassic acid, 3-O-(beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl)-28-O-(alpha-L-rhamnopyranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)[beta-D-apiofuranosyl-(1-->3)]-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl)-16alpha-hydroxyprotobassic acid, and the known compound, 3-O-beta-D-glucopyranosyl-28-O-(alpha-L-rhamnopyranosyl-(1-->3)[beta-D-xylopyranosyl-(1-->4)]-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl)-protobassic acid. Two further saponins were obtained from the same fraction, but as a 5:4 mixture comprising 3-O-(beta-D-glucopyranosyl)-28-O-(alpha-L-rhamnopyranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)[beta-D-apiofuranosyl-(1-->3)]-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl)-16alpha-hydroxyprotobassic acid and 3-O-(beta-D-apiofuranosyl-(1-->3)-beta-D-glucopyranosyl)-28-O-(alpha-L-rhamnopyranosyl-(1-->3)[beta-D-xylopyranosyl-(1-->4)]-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl)-16alpha-hydroxyprotobassic acid, respectively. This showed greater cytotoxicity (IC(50)=11.9+/-1.5 microg/ml) towards RAW 264.7 cells than the original extract (IC(50)=39.5+/-4.1 microg/ml), and the saponin-containing fraction derived from it (IC(50)=33.7+/-6.2 microg/ml).


Assuntos
Extratos Vegetais/química , Raízes de Plantas/química , Saponinas/isolamento & purificação , Sapotaceae/química , Triterpenos/isolamento & purificação , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Sequência de Carboidratos , Linhagem Celular , Espectroscopia de Ressonância Magnética , Camundongos , Dados de Sequência Molecular , Saponinas/química , Saponinas/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Triterpenos/química , Triterpenos/farmacologia
4.
Eur Heart J ; 25(10): 847-53, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15140532

RESUMO

AIMS: To investigate whether the vasoconstrictor isoprostane F2alpha-III (iPF2alpha-III), released during myocardial reperfusion, contributes to the low/no reflow phenomenon observed following acute myocardial infarction (AMI). METHODS AND RESULTS: Thirteen patients undergoing primary percutaneous coronary intervention (PCI) for AMI had iPF2alpha-III measured by high-performance liquid and gas chromatography-mass spectrometry. Isoprostane F2alpha-III concentrations were significantly higher following PCI than in controls (1.5+/-1.3 vs.16+/-0.06 nM, p < 0.001). Mean iPF2alpha-III concentration correlated positively with ST-segment resolution at 90 min (R = 0.62, p < 0.05). In the isolated murine heart: (a) coronary vasoconstriction occurred at, or above, iPF2alpha-III concentrations of 1 microM. From 1 to 10 microM, iPF2alpha-III induced dose-dependent vasoconstriction (p = 0.005) with reduction in coronary flows (f) of 57+/-5% and 31+/-4% (percentage baseline), respectively; (b) SQ29548 1 microM completely reversed the vasoconstrictive effects of iPF2alpha-III 10 microM; (c) SQ29548 1 microM infused during reperfusion following 30 min ischaemia had no effect on CF or infarct volume. CONCLUSION: Concentrations of iPF2alpha-III released into the venous circulation during reperfusion following AMI in humans are significantly lower than those required to diminish coronary flow in the murine heart; increased levels indicate successful reperfusion. Inhibition of iPF2alpha-III has no effect on coronary flow or infarct size in the murine heart, suggesting that iPF2alpha-III alone does not account for the low/no reflow phenomenon observed following AMI.


Assuntos
Angioplastia Coronária com Balão/métodos , Isoprostanos/sangue , Infarto do Miocárdio/metabolismo , Reperfusão Miocárdica/métodos , Vasodilatadores/metabolismo , Animais , Circulação Coronária/fisiologia , Feminino , Humanos , Masculino , Camundongos , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Estudos Prospectivos
5.
Am J Obstet Gynecol ; 187(1): 127-36, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12114900

RESUMO

OBJECTIVE: The purpose of this study was to characterize gestational profiles of biochemical markers that are associated with preeclampsia in the blood of pregnant women in whom preeclampsia developed later and to compare these markers with the markers of women who were delivered of small-for-gestational-age infants without preeclampsia and with women who were at low risk for the development of preeclampsia. STUDY DESIGN: This was a prospective case control study. The subjects were women at risk of preeclampsia who were enrolled in the placebo arm of a clinical trial. Indices of antioxidant status, oxidative stress, placental and endothelial function, and serum lipid concentrations were evaluated from 20 weeks of gestation until delivery in 21 women in whom preeclampsia developed later, in 17 women without preeclampsia who were delivered of small-for-gestational-age infants, and in 27 women who were at low risk for the development of preeclampsia. RESULTS: Ascorbic acid was reduced early in preeclampsia and small-for-gestational-age pregnancies. Leptin, placenta growth factor, the plasminogen activator inhibitor (PAI-1)/PAI-2 ratio, and uric acid were predictive of the development of preeclampsia. CONCLUSION: Gestational profiles of several markers were abnormal in the group with preeclampsia, and some of the markers that may prove useful in the selective prediction of preeclampsia were identified.


Assuntos
Dinoprosta/análogos & derivados , Estresse Oxidativo , Pré-Eclâmpsia/metabolismo , Algoritmos , Pressão Sanguínea , Estudos de Casos e Controles , Endotélio/fisiopatologia , F2-Isoprostanos/sangue , Feminino , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Lipídeos/sangue , Estudos Longitudinais , Inibidor 1 de Ativador de Plasminogênio/sangue , Inibidor 2 de Ativador de Plasminogênio/sangue , Pré-Eclâmpsia/sangue , Gravidez , Curva ROC , Fatores de Risco , Sensibilidade e Especificidade
6.
J Biol Chem ; 277(31): 27887-95, 2002 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-12023966

RESUMO

Polymorphonuclear leukocytes represent primary components of the host's innate immune defenses against fungal infection, suggesting involvement of fungal leukocyte attractants. We have found in various fungi, but not in bacteria or host cells, unstable lipid-like leukocyte chemoattractants, which also induced adherence and degranulation in human neutrophils. Purification from bakers' yeast and structural analyses by electrospray mass spectrometry, (1)H NMR spectroscopy, and chemical synthesis revealed these inflammatory mediators as diacylated ureas, a novel class of unstable lipoids. The N,N'-dipalmitoleyl urea appeared to be the most potent innate immune responses inducing compound eliciting half-maximum neutrophil chemotactic activity at 140 nm. The all-trans isomer, N,N'-dipalmitelaidyl urea, was found to be inactive with respect to stimulation of degranulation in neutrophils, which indicates a Delta(9) cis-double bond to be essential for bioactivity of these diacyl ureas. N,N'-Dipalmitoleyl urea elicited Ca(2+) mobilization in neutrophils, which was found to be pertussis toxin-sensitive and sensitive toward a carboxylmethyltransferase inhibitor, indicating that these diacyl ureas activate leukocytes via a putative Galpha(i)-protein-coupled receptor. Their isolation exclusively from fungi suggests that these lipoids are fungus-specific pathogen-associated molecules that may alert the human innate immunity system to the presence of a fungal infection.


Assuntos
Sinalização do Cálcio/fisiologia , Neutrófilos/microbiologia , Saccharomyces cerevisiae/fisiologia , Ureia/análogos & derivados , Ureia/metabolismo , Acilação , Humanos , Inflamação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Ureia/química
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