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2.
Mol Ther Nucleic Acids ; 30: 465-476, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36345542

RESUMO

The emerging SARS-CoV-2 variants of concern (VOCs) exhibit enhanced transmission and immune escape, reducing the effectiveness of currently approved mRNA vaccines. To achieve wider coverage of VOCs, we first constructed a cohort of mRNAs harboring a furin cleavage mutation in the spike (S) protein of predominant VOCs, including Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), and Delta (B.1.617.2). The mutation abolished the cleavage between the S1 and S2 subunits. Systematic evaluation in vaccinated mice discovered that individual VOC mRNAs elicited strong neutralizing activity in a VOC-specific manner. In particular, the neutralizing antibodies (nAb) produced by immunization with Beta-Furin and Washington (WA)-Furin mRNAs showed potent cross-reactivity with other VOCs. However, neither mRNA elicited strong neutralizing activity against the Omicron variant. Hence, we further developed an Omicron-specific mRNA vaccine that restored protection against the original Omicron variant and some sublineages. Finally, to broaden the protection spectrum of the new Omicron mRNA vaccine, we engineered an mRNA-based chimeric immunogen by introducing the receptor-binding domain of Delta variant into the entire S antigen of Omicron. The resultant chimeric mRNA induced potent and broadly nAbs against Omicron and Delta, which paves the way to developing new vaccine candidates to target emerging variants in the future.

3.
Drug Deliv Transl Res ; 11(1): 182-191, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32378175

RESUMO

PD98059 is a reversible MEK inhibitor that we are investigating as a potential treatment for neurochemical changes in the brain that drive neurohumoral excitation in heart failure. In a rat model that closely resembles human heart failure, we found that central administration of PD98059 inhibits phosphorylation of ERK1/2 in the paraventricular nucleus of the hypothalamus, ultimately reducing sympathetic excitation which is a major contributor to clinical deterioration. Studies revealed that the pharmacokinetics and biodistribution of PD98059 match a two-compartment model, with drug found in brain as well as other body tissues, but with a short elimination half-life in plasma (approximately 73 min) that would severely limit its potential clinical usefulness in heart failure. To increase its availability to tissues, we prepared a sustained release PD98059-loaded PLGA microparticle formulation, using an emulsion solvent evaporation technique. The average particle size, yield percent, and encapsulation percent were found to be 16.73 µm, 76.6%, and 43%, respectively. In vitro drug release occurred over 4 weeks, with no noticeable burst release. Following subcutaneous injection of the microparticles in rats, steady plasma levels of PD98059 were detected by HPLC for up to 2 weeks. Furthermore, plasma and brain levels of PD98059 in rats with heart failure were detectable by LC/MS, despite expected erratic absorption. These findings suggest that PD98059-loaded microparticles hold promise as a novel therapeutic intervention countering sympathetic excitation in heart failure, and perhaps in other disease processes, including cancers, in which activated MAPK signaling is a significant contributing factor. Graphical abstract.


Assuntos
Flavonoides , Quinases de Proteína Quinase Ativadas por Mitógeno , Animais , Preparações de Ação Retardada , Microesferas , Tamanho da Partícula , Ratos , Distribuição Tecidual
4.
Molecules ; 22(10)2017 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-29064442

RESUMO

A Western lifestyle with low physical activity and a diet rich in sugar, fat and processed food contribute to higher incidences of diabetes and obesity. Enhanced glucose uptake in human liver cells was observed after treatment with phenolic extracts from different Nordic berries. All berry extracts showed higher inhibition against α-amylase and α-glucosidase than the anti-diabetic agent acarbose. Total phenolic content and phenolic profiles in addition to antioxidant activities, were also investigated. The berries were extracted with 80% methanol on an accelerated solvent extraction system (ASE) and then purified by C-18 solid phase extraction (SPE). Among the ASE methanol extracts, black chokeberry, crowberry and elderberry extracts showed high stimulation of glucose uptake in HepG2 cells and also considerable inhibitory effect towards carbohydrate hydrolyzing enzymes. SPE extracts with higher concentrations of phenolics, resulted in increased glucose uptake and enhanced inhibition of α-amylase and α-glucosidase compared to the ASE extracts. Crowberry and cloudberry were the most potent 15-lipoxygenase inhibitors, while bog whortleberry and lingonberry were the most active xanthine oxidase inhibitors. These results increase the value of these berries as a component of a healthy Nordic diet and have a potential benefit against diabetes.


Assuntos
Frutas/química , Glucose/metabolismo , Inibidores de Glicosídeo Hidrolases/química , Metabolismo dos Carboidratos , Inibidores de Glicosídeo Hidrolases/farmacologia , Células Hep G2 , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extração em Fase Sólida/métodos , Xantina Oxidase/antagonistas & inibidores , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases/metabolismo
5.
J Agric Food Chem ; 65(13): 2677-2685, 2017 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-28303711

RESUMO

Uptake of glucose and fatty acids in skeletal muscle is of interest for type 2 diabetes treatment. The aim was to study glucose and fatty acid uptake in skeletal muscle cells, antioxidant effects, and inhibition of carbohydrate-hydrolyzing enzymes by elderberries. Enhanced glucose and oleic acid uptake in human skeletal muscle cells were observed after treatment with phenolic elderberry extracts, anthocyanins, procyanidins, and their metabolites. The 96% EtOH and the acidified MeOH extracts were highly active. Of the isolated substances, cyanidin-3-glucoside and cyanidin-3-sambubioside showed highest stimulation of uptake. Phloroglucinol aldehyde was most active among the metabolites. Isolated anthocyanins and procyanidins are strong radical scavengers and are good inhibitors of 15-lipoxygenase and moderate inhibitors of xanthine oxidase. As α-amylase and α-glucosidase inhibitors, they are considerably better than the positive control acarbose. The antidiabetic property of elderberry phenolics increases the nutritional value of this plant and indicates potential as functional food against diabetes.


Assuntos
Antocianinas/metabolismo , Biflavonoides/metabolismo , Catequina/metabolismo , Ácidos Graxos/metabolismo , Glucose/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Fenóis/metabolismo , Extratos Vegetais/metabolismo , Proantocianidinas/metabolismo , Sambucus/metabolismo , Adolescente , Adulto , Antocianinas/isolamento & purificação , Biflavonoides/isolamento & purificação , Catequina/isolamento & purificação , Células Cultivadas , Feminino , Frutas/química , Frutas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Músculos Oculomotores/citologia , Músculos Oculomotores/metabolismo , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Proantocianidinas/isolamento & purificação , Sambucus/química , Células Satélites de Músculo Esquelético/metabolismo , Adulto Jovem
6.
Int J Mol Sci ; 18(3)2017 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-28282861

RESUMO

Modulation of complement activity and inhibition of nitric oxide (NO) production by macrophages and dendritic cells may have therapeutic value in inflammatory diseases. Elderberry and elderflower extracts, constituents, and metabolites were investigated for their effects on the complement system, and on NO production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages and murine dendritic D2SC/I cells. The EtOH crude extracts from elderberry and elderflower and the isolated anthocyanins and procyanidins possessed strong complement fixating activity and strong inhibitory activity on NO production in RAW cells and dendritic cells. Phenolic compounds in the range of 0.1-100 µM showed a dose-dependent inhibition of NO production, with quercetin, rutin, and kaempferol as the most potent ones. Among the metabolites, caffeic acid and 3,4-dihydroxyphenylacetic acid showed the strongest inhibitory effects on NO production in both cell lines, without having cytotoxic effect. Only 4-methylcatechol was cytotoxic at the highest tested concentration (100 µM). Elderberry and elderflower constituents may possess inflammatory modulating activity, which increases their nutritional value.


Assuntos
Ativação do Complemento/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Flores/química , Macrófagos/efeitos dos fármacos , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Sambucus/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fracionamento Químico , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Flavonoides , Hemólise/efeitos dos fármacos , Lipopolissacarídeos/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Fenóis/química , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química
7.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1044-1045: 70-76, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28088043

RESUMO

A sensitive and precise method is described for the simultaneous determination of two small molecule kinase inhibitors: MK-1775 (MK) and AZD-7762 (AZD), in acetonitrile (ACN)-aqueous solution and in mouse plasma. A Nova-Pak C18 reversed phase column (3.9mm×150mm, 4µm, 60Å) was utilized in the separation using an isocratic mobile phase of 0.1% v/v triethylamine in phosphate buffer (pH=7.4): acetonitrile (ACN) (60:40, v/v), at a flow rate of 0.8mL/min. Detection wavelength was set at 310nm for both MK and AZD, and 431nm for the internal standard sunitinib (SUN). The developed method was validated following the ICH guidelines and it was shown to be accurate, precise and linear in the range of 41ng/mL to 8333ng/mL for both drugs in the ACN-aqueous solution and from 83ng/mL to 8333ng/mL for both drugs in mouse plasma samples. For the first time, the presented data suggest the suitability of this method for the simultaneous separation and quantification of MK and AZD in both ACN aqueous solution as well as in mouse plasma samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Pirazóis/análise , Pirimidinas/análise , Tiofenos/análise , Ureia/análogos & derivados , Animais , Feminino , Limite de Detecção , Modelos Lineares , Camundongos , Camundongos Endogâmicos BALB C , Pirazóis/sangue , Pirazóis/química , Pirimidinas/sangue , Pirimidinas/química , Pirimidinonas , Reprodutibilidade dos Testes , Extração em Fase Sólida , Espectrofotometria Ultravioleta , Tiofenos/sangue , Tiofenos/química , Ureia/análise , Ureia/sangue , Ureia/química
8.
Molecules ; 22(1)2017 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-28067838

RESUMO

Type 2 diabetes (T2D) is manifested by progressive metabolic impairments in tissues such as skeletal muscle and liver, and these tissues become less responsive to insulin, leading to hyperglycemia. In the present study, stimulation of glucose and oleic acid uptake by elderflower extracts, constituents and metabolites were tested in vitro using the HepG2 hepatocellular liver carcinoma cell line and human skeletal muscle cells. Among the crude extracts, the 96% EtOH extract showed the highest increase in glucose and oleic acid uptake in human skeletal muscle cells and HepG2-cells. The flavonoids and phenolic acids contained therein were potent stimulators of glucose and fatty acid uptake in a dose-dependent manner. Most of the phenolic constituents and several of the metabolites showed high antioxidant activity and showed considerably higher α-amylase and α-glucosidase inhibition than acarbose. Elderflower might therefore be valuable as a functional food against diabetes.


Assuntos
Antioxidantes/farmacologia , Flavonoides/farmacologia , Hipoglicemiantes/farmacologia , Células Musculares/efeitos dos fármacos , Fenóis/farmacologia , Sambucus nigra/química , Acarbose/farmacologia , Animais , Antioxidantes/isolamento & purificação , Transporte Biológico , Compostos de Bifenilo/antagonistas & inibidores , Linhagem Celular , Relação Dose-Resposta a Droga , Flavonoides/isolamento & purificação , Flores/química , Glucose/metabolismo , Células Hep G2 , Humanos , Hipoglicemiantes/isolamento & purificação , Células Musculares/citologia , Células Musculares/metabolismo , Ácido Oleico/metabolismo , Fenóis/isolamento & purificação , Picratos/antagonistas & inibidores , Extratos Vegetais/química , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/enzimologia , Suínos , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/química , alfa-Glucosidases/química
9.
Int J Biol Macromol ; 92: 731-738, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27475233

RESUMO

Sambuci flos, also known as elderflower, has traditionally been used and is still in use for treatment of various types of illnesses related to the immune system such as cold, flu, fever and inflammation. Pectic polysaccharides from 50% EtOH, 50°C water and 100°C water extracts from elderflowers were treated with endo-α-d-(1-4)-polygalacturonase after previous de-esterification with the intention of isolating hairy regions and relate variation in structure to immunomodulating activity. High molecular weight sub-fractions (25-29kDa) and medium molecular weight sub-fractions (6-17kDa) were isolated after enzymatic treatment in addition to oligogalacturonides. Structural elucidation indicated that RG-I regions with AG-I and AG-II sidechains were the predominant structures in the high molecular weight sub-fractions, and two of three 1,4-linked GalA units in the rhamnogalacturonan backbone were branched in either position 2 or 3. The medium molecular weight sub-fractions had monomers and linkages typical for both RG-I and RG-II. The results showed that the high molecular RG-I containing polymers exhibit the highest dose-dependent complement fixing and macrophage stimulating activities.


Assuntos
Flores/química , Ácidos Hexurônicos/química , Fatores Imunológicos/farmacologia , Pectinas/farmacologia , Sambucus nigra/química , Animais , Artemia , Sequência de Carboidratos , Linhagem Celular , Testes de Fixação de Complemento , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Humanos , Hidrólise , Soros Imunes/química , Soros Imunes/farmacologia , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Peso Molecular , Óxido Nítrico/biossíntese , Óxido Nítrico/imunologia , Pectinas/química , Pectinas/isolamento & purificação , Extratos Vegetais/química , Poligalacturonase/química , Ovinos
10.
Fitoterapia ; 109: 196-200, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26802607

RESUMO

Heitziquinone (7), a new benzophenanthridine alkaloid, together with five known compounds; isoarnottianamide (5), rhoifoline B (6), isobauerenol (8), 6-hydroxypellitorine (9) and sylvamide (10), were isolated as minor compounds from the hexane extract of stem bark from Zanthoxylum heitzii. Four previously reported compounds (1-4) were found, as well. Compounds 5 and 7 were both found to exist as 4:1 mixtures of two atropisomers. The structures were elucidated by 1D and 2D NMR spectroscopy and by mass spectrometry. Compounds 5-10 were identified for the first time in this species, and they are all rare natural compounds. Pellitorine (4), one of the main compounds from the hexane bark extract, was found to be responsible for the brine shrimp larvae toxicity (LC50 37 µM, 8 µg/ml) of the crude extract (LC50 24 µg/ml). Low cytotoxicity against a macrophage cell line was observed.


Assuntos
Benzofenantridinas/química , Casca de Planta/química , Zanthoxylum/química , Animais , Artemia/efeitos dos fármacos , Benzofenantridinas/isolamento & purificação , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/isolamento & purificação , Camundongos , Estrutura Molecular , Extratos Vegetais/química , Caules de Planta/química , Alcamidas Poli-Insaturadas/química , Alcamidas Poli-Insaturadas/isolamento & purificação , Células RAW 264.7 , Testes de Toxicidade
11.
Carbohydr Polym ; 135: 128-37, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26453860

RESUMO

Elderflowers have traditionally been used and are still used for its anti-inflammatory property. Traditionally elderflowers were used as remedies against cold, flu and diuretic. The aim of this study was to relate the structure of pectic-polysaccharides from elderflowers to immunomodulating properties. Purified fractions obtained by gelfiltration and ion exchange chromatography of 50% ethanol, 50°C water and 100°C water extracts exhibited strong complement fixating activity and macrophage stimulating activity. Reduced bioactivity was observed after removal of arabinose and 1,3,6-Gal linkages by weak acid hydrolysis. Enhanced bioactivity was observed after removal of estergroups by NaOH. Relating linkage analysis to the results of the bioactivity tests, led to the assumption that the branched moieties of the arabinogalactans linked to rhamnogalacturonan region, is important for the immunomodulating activity seen in elderflowers. No cytotoxity was observed.


Assuntos
Flores/química , Polissacarídeos/química , Sambucus , Animais , Artemia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cromatografia por Troca Iônica , Testes de Fixação de Complemento , Hidrólise , Larva/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Peso Molecular , Monossacarídeos/análise , Óxido Nítrico/metabolismo , Ácido Oxálico/química , Fenóis/análise , Proteínas de Plantas/análise , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Espectrofotometria Infravermelho
12.
Carbohydr Polym ; 125: 314-22, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-25857988

RESUMO

The berries of Sambucus nigra have traditionally been used and are still used to treat respiratory illnesses such as cold and flu in Europe, Asia and America. The aim of this paper was to elucidate the structures and the immunomodulating properties of the pectic polymers from elderberries. All the purified fractions obtained from 50% ethanol, 50°C water and 100°C water extracts showed potent dose-dependent complement fixating activity and macrophage stimulating activity. The isolated fractions consisted of long homogalacturonan regions, in addition to arabinogalactan-I and arabinogalactan-II probably linked to a rhamnogalacturonan backbone. Reduced bioactivity was observed after reduction of Araf residues and 1→3,6 Gal by weak acid hydrolysis. The rhamnogalacturonan region in SnBe50-I-S3-I and SnBe50-I-S3-II showed higher activity compared to the native polymer, SnBe50-S3, after enzymatic treatment with endo-α-d-(1→4)-polygalacturonase. These results indicated that elderberries contained immunomodulating polysaccharides, where the ramified regions express the activities observed.


Assuntos
Fatores Imunológicos/química , Pectinas/química , Sambucus/química , Animais , Artemia/efeitos dos fármacos , Linhagem Celular , Hemólise/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Fatores Imunológicos/toxicidade , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Pectinas/farmacologia , Pectinas/toxicidade , Ovinos , Relação Estrutura-Atividade
13.
Carbohydr Res ; 403: 167-73, 2015 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-24909378

RESUMO

The root bark, stem bark, and leaves of Terminalia macroptera were sequentially extracted with ethanol, 50% ethanol-water, and 50°C water using an accelerated solvent extractor (ASE). Six bioactive purified pectic polysaccharide fractions were obtained from the 50°C crude water extracts after anion exchange chromatography and gel filtration. The root bark, stem bark, and leaves of T. macroptera were all good sources for fractions containing bioactive polysaccharides. The high molecular weight fraction 50WTRBH-I-I, being the most active fraction in the complement fixation test, has a highly ramified rhamnogalacturonan type I (RG-I) region with arabinogalactan type II (AG-II) side chains. The most abundant fractions from each plant part, 50WTRBH-II-I, 50WTSBH-II-I, and 50WTLH-II-I, were chosen for pectinase degradation. The degradation with pectinase revealed that the main features of these fractions are that of pectic polysaccharides, with hairy regions (RG-I regions) and homogalacturonan regions. The activity of the fractions obtained after pectinase degradation and separation by gel filtration showed that the highest molecular weight fractions, 50WTRBH-II-Ia, 50WTSBH-II-Ia, and 50WTLH-II-Ia, had higher complement fixation activity than their respective native fractions. These results suggest that the complement fixation activities of these pectins are expressed mainly by their ramified regions.


Assuntos
Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Pectinas/química , Pectinas/farmacologia , Terminalia/química , Árvores/química , Sequência de Carboidratos , Proteínas do Sistema Complemento/metabolismo , Humanos , Hidrólise , Fatores Imunológicos/isolamento & purificação , Fatores Imunológicos/metabolismo , Dados de Sequência Molecular , Monossacarídeos/análise , Pectinas/isolamento & purificação , Pectinas/metabolismo , Casca de Planta/química , Folhas de Planta/química , Raízes de Plantas/química , Poligalacturonase/metabolismo , Relação Estrutura-Atividade
14.
Beilstein J Nanotechnol ; 5: 1261-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25247110

RESUMO

The effect of palladium doping of zinc oxide nanoparticles on the photoluminescence (PL) properties and hydrogen sensing characteristics of gas sensors is investigated. The PL intensity shows that the carrier dynamics coincides with the buildup of the Pd-related green emission. The comparison between the deep level emission and the gas sensing response characteristics allows us to suggest that the dissociation of hydrogen takes place at PdZn-vacancies ([Pd (2+)(4d(9))]). The design of this sensor allows for a continuous monitoring in the range of 0-100% LEL H2 concentration with high sensitivity and selectivity.

15.
J Ethnopharmacol ; 155(2): 1219-26, 2014 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-25017373

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The root bark, stem bark and leaves of Terminalia macroptera have been traditionally used against a variety of ailments such as wounds, hepatitis, malaria, fever, cough, and diarrhea as well as tuberculosis and skin diseases in African folk medicine. Boiling water extracts of Terminalia macroptera, administered orally, are the most common preparations of this plant used by the traditional healers in Mali. This study aimed to investigate the inhibition of the activities of α-glucosidase, 15-lipoxygenase and xanthine oxidase, DPPH scavenging activity, complement fixation activity and brine shrimp toxicity of different extracts obtained by boiling water extraction (BWE) and by ASE (accelerated solvent extraction) with ethanol, ethanol-water and water as extractants from different plant parts of Terminalia macroptera. MATERIALS AND METHODS: 27 different crude extracts were obtained by BWE and ASE from root bark, stem bark and leaves of Terminalia macroptera. The total phenolic and carbohydrate contents, enzyme inhibition activities (α-glucosidase, 15-lipoxygenase and xanthine oxidase), DPPH scavenging activity, complement fixation activity and brine shrimp toxicity of these extracts were evaluated. Principal component analysis (PCA) was applied for total biological activities evaluation. RESULTS: Several of the extracts from root bark, stem bark and leaves of Terminalia macroptera obtained by BWE and ASE showed potent enzyme inhibition activities, radical-scavenging properties and complement fixation activities. None of the extracts are toxic against brine shrimp larvae in the test concentration. Based on the results from PCA, the ASE ethanol extracts of root bark and stem bark and the low molecular weight fraction of the 50% ethanol-water extract of leaves showed the highest total biological activities. The boiling water extracts were less active, but the bark extracts showed activity as α-glucosidase inhibitors and radical scavengers, the leaf extract being less active. CONCLUSION: The observed enzyme inhibition activities, radical scavenging properties and complement fixation activities may explain some of the traditional uses of this medicinal tree, such as in wound healing and against diabetes.


Assuntos
Antioxidantes/farmacologia , Artemia/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Fatores Imunológicos/farmacologia , Extratos Vegetais/farmacologia , Terminalia , Animais , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/toxicidade , Compostos de Bifenilo/química , Ativação do Complemento/efeitos dos fármacos , Testes de Fixação de Complemento , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/toxicidade , Inibidores de Glicosídeo Hidrolases/farmacologia , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação , Fatores Imunológicos/toxicidade , Dose Letal Mediana , Inibidores de Lipoxigenase/farmacologia , Fitoterapia , Picratos/química , Casca de Planta , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Folhas de Planta , Raízes de Plantas , Caules de Planta , Plantas Medicinais , Análise de Componente Principal , Ovinos , Terminalia/química , Xantina Oxidase/antagonistas & inibidores , Xantina Oxidase/metabolismo
16.
Int J Mol Sci ; 15(7): 11626-36, 2014 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-24983479

RESUMO

The immunomodulating effects of isolated proanthocyanidin-rich fractions, procyanidins C1, B5 and B2 and anthocyanins of Aronia melanocarpa were investigated. In this work, the complement-modulating activities, the inhibitory activities on nitric oxide (NO) production in LPS-induced RAW 264.7 macrophages and effects on cell viability of these polyphenols were studied. Several of the proanthocyanidin-rich fractions, the procyanidins C1, B5 and B2 and the cyanidin aglycone possessed strong complement-fixing activities. Cyanidin 3-glucoside possessed stronger activity than the other anthocyanins. Procyanidins C1, B5 and B2 and proanthocyanidin-rich fractions having an average degree of polymerization (PD) of 7 and 34 showed inhibitory activities on NO production in LPS-stimulated RAW 264.7 mouse macrophages. All, except for the fraction containing proanthocyanidins with PD 34, showed inhibitory effects without affecting cell viability. This study suggests that polyphenolic compounds of A. melanocarpa may have beneficial effects as immunomodulators and anti-inflammatory agents.


Assuntos
Fatores Imunológicos/farmacologia , Photinia/química , Polifenóis/farmacologia , Animais , Antocianinas/química , Antocianinas/farmacologia , Fatores Imunológicos/química , Ativação de Macrófagos , Macrófagos/efeitos dos fármacos , Camundongos , Óxido Nítrico/metabolismo , Polifenóis/química , Proantocianidinas/química , Proantocianidinas/farmacologia
17.
Talanta ; 115: 713-7, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24054652

RESUMO

In this paper, poly(1,5-diaminonaphthalene) was interpenetrated into the network made of multiwalled carbon nanotubes (MWCNT) on platinum interdigital electrode (IDE) by electro-polymerization of 1,5-diaminonaphthalene (1,5-DAN). The electro-polymerization process of 1,5-DAN on MWCNT was controlled by scanning the cyclic voltage at 50 mV s(-1) scan rate between -0.1 V and +0.95 V vs. saturated calomel electrode (SCE). The results of voltammetric responses and Raman spectroscopy represented that the films MWCNT/poly(1,5-DAN) were successfully created by this polymerization process. The films MWCNT/poly(1,5-DAN) were investigated for gas-sensing to NO2 at low concentration level. The gas-sensing results showed that the response-recovery times were long and strongly affected by thickness of the film MWCNT/poly(1,5-DAN). Nevertheless, these films represented auspicious results for gas sensors operating at room temperature.


Assuntos
2-Naftilamina/análogos & derivados , Poluentes Atmosféricos/análise , Nanotubos de Carbono/química , Dióxido de Nitrogênio/análise , 2-Naftilamina/química , Catálise , Técnicas Eletroquímicas , Eletrodos , Desenho de Equipamento , Concentração de Íons de Hidrogênio , Platina , Polimerização , Temperatura
18.
Naturwissenschaften ; 99(9): 687-94, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22847810

RESUMO

Some members of the family Tachinidae (Insecta: Diptera) deposit numerous very small eggs, termed "microtype" eggs, on the food plants of their caterpillar hosts. Parasitization is successful only when the hosts ingest these eggs. To increase the chance of hosts encountering the eggs, microtype tachinid parasitoids have to choose a suitable plant that harbors hosts and lay their eggs near the hosts. In their host location process, semiochemicals emitted by host-infested plants offer the tachinids a reliable cue. We investigated the behavioral responses of two microtype tachinid parasitoids, Pales pavida and Zenillia dolosa, to maize plants infested with their caterpillar host, Mythimna separata, in a wind tunnel. P. pavida females showed a significantly higher rate of landing on caterpillar-infested plants than on mechanically wounded or intact plants, whereas Z. dolosa landed on both the caterpillar-infested and mechanically wounded plants at significantly higher rates than on intact plants. We also examined which part of a caterpillar-infested maize leaf induces oviposition. P. pavida deposited eggs on the margin of the leaf, whereas Z. dolosa preferentially laid eggs around a caterpillar-infested area or a mechanically wounded spot. P. pavida eggs retained their parasitization ability for more than 15 days after they were deposited, whereas the eggs of Z. dolosa could not survive more than 5 days after oviposition. Our results suggest that each tachinid parasitoid employs a different host location strategy to exploit semiochemicals coming from plant-herbivore interaction as cues in order to increase their parasitization success.


Assuntos
Dípteros/fisiologia , Interações Hospedeiro-Parasita , Feromônios/fisiologia , Zea mays/parasitologia , Animais , Feminino , Longevidade , Mariposas/parasitologia , Oviposição/fisiologia , Folhas de Planta/parasitologia , Fatores de Tempo
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