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1.
Food Res Int ; 106: 817-824, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29579992

RESUMEN

This investigation aimed to examine the effects of a novel processing pattern, combining high hydrostatic pressure (HHP) with germination, on the embryo growth and physicochemical characteristics of wholegrain brown rice (WBR). WBR grains were firstly subjected to mild HHP stress (30-90 MPa/5 min) and then incubated at 37 °C for 52 h for obtaining germinated samples (GBR). The results showed that HHP shock resulted in a delayed embryo growth of WBR grains, maintaining acceptable sprouting rates ranging from 65% to 76% when germination was finished. The contents of gama-aminobutyric acid in GBR were greatly increased responding to HHP stress, showing pressure intensities dependent. Total digestible and resistant starch contents in samples stressed at 60/90 MPa were decreased, mainly associated with high pressure-induced amorphization as revealed by SEM imaging and FTIR, which promoted starch hydrolysis during germination. Besides, the levels of zinc and iron were influenced by HHP pretreatments due to the high pressure-mediated degradation behavior for phytic acids. The storability of HHP-stressed GBR grains was significantly enhanced through reducing free fatty acids formation and maintaining color stability during a storage testing. These results obtained from the current work demonstrated that mild HHP stress pretreatment prior to germination process could be used as a promising strategy to modulate certain physicochemical characteristics of WBR products.


Asunto(s)
Manipulación de Alimentos , Germinación , Oryza/química , Granos Enteros/química , Aminoácidos/análisis , Color , Calidad de los Alimentos , GABAérgicos/análisis , Hidrólisis , Presión Hidrostática , Hierro/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Almidón/química , Zinc/análisis
2.
Food Chem ; 145: 77-85, 2014 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-24128451

RESUMEN

We profiled and quantified glucosinolates (GSLs), anthocyanins, free amino acids, and vitamin C metabolites in forty-five lines of green and red cabbages. Analysis of these distinct cabbages revealed the presence of 11 GSLs, 13 anthocyanins, 22 free amino acids, and vitamin C. GSL contents were varied amongst the different lines of cabbage. The total GSL content was mean 10.6 µmol/g DW, and sinigrin was the predominant GSL accounted mean 4.0 µmol/g DW (37.7% of the total) followed by glucoraphanin (1.9) and glucobrassicin (2.4). Amongst the 13 anthocyanins, cyanidin 3-(sinapoyl) diglucoside-5-glucoside levels were the highest. The amounts of total free amino acids in green cabbage lines ranged 365.9 mg/100g fresh weight (FW) to 1089.1mg/100g FW. Vitamin C levels were much higher in red cabbage line (129.9 mg/100g FW). Thus, the amounts of GSLs, anthocyanins, free amino acids, and vitamin C varied widely, and the variations in these compounds between the lines of cabbage were significant.


Asunto(s)
Aminoácidos/análisis , Antocianinas/análisis , Ácido Ascórbico/análisis , Brassica/química , Glucosinolatos/análisis , Imidoésteres/análisis , Indoles/análisis , Brassica/clasificación , Análisis de los Alimentos , GABAérgicos/análisis , Oximas , Sulfóxidos , Vitaminas
3.
Adicciones (Palma de Mallorca) ; 26(4): 360-370, 2014. ilus
Artículo en Español | IBECS | ID: ibc-131875

RESUMEN

Todavía se desconoce el mecanismo exacto mediante el cual el etanol produce sus efectos en el cerebro. Sin embargo, hoy en día se sabe que el etanol interactúa con proteínas específicas de la membrana neuronal, implicadas en la transmisión de señales, produciendo así alteraciones en la actividad neuronal. En este artículo de revisión se describen diferentes alteraciones neuroquímicas producidas por esta droga. En primer lugar, el etanol actúa sobre dos receptores de membrana: los receptores ionotrópicos GABAA y NMDA. Eletanol potencia la acción del GABA y antagoniza la del glutamato, actuando de esta manera como un depresor del SNC. Además, eletanol afecta a la mayoría de sistemas neuroquímicos y endocrinos. En cuanto al sistema de recompensa, tanto el sistema opioide como el dopaminérgico se ven alterados por esta droga. Igualmente, los sistemas serotonérgico, noradrenérgico, cannabinoide y el sistema del factor liberador de corticotropina, tienen un papel importante en la neurobiología del alcoholismo. Por otro lado, el etanol también puede modular componentes citosólicos, entre los cuales se encuentran los segundos mensajeros. Asimismo, en este artículo de revisión se presentan los tratamientos farmacológicos actuales para el alcoholismo, así como diferentes tratamientos potenciales de futuro, basados en resultados de investigaciones en curso


The exact mechanism by which ethanol exerts its effects on the brain is still unknown. However, nowadays it is well known that ethanol interacts with specific neuronal membrane proteins involved in signal transmission, resulting in changes in neural activity. In this review different neurochemical alterations produced by ethanol are described. Primarily, ethanol interacts with two membrane receptors: GABAA and NMDA ion channel receptors. Ethanol enhances the GABA action and antagonizes glutamate action, therefore acting as a CNS depressant. In addition, ethanol affects most other neurochemical and endocrine systems. In regard to the brain reward system, both dopaminergic and opioid system are affected by this drug. Furthermore, the serotonergic, noradrenergic, corticotrophin releasing factor and cannabinoid systems seem to play an important role in the neurobiology of alcoholism. At last but not least, ethanol can also modulate cytoplasmic components, including the second messengers. We also review briefly the different actual and putative pharmacological treatments for alcoholism, based on the alterations produced by this drug


Asunto(s)
Humanos , Etanol/efectos adversos , Alcoholismo/fisiopatología , Trastornos del Sistema Nervioso Inducidos por Alcohol/fisiopatología , Trastornos Relacionados con Alcohol/fisiopatología , GABAérgicos/análisis , Ácido Glutámico/análisis , Neurotransmisores/análisis
4.
Med Chem ; 7(4): 317-24, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21568883

RESUMEN

Some phenols, like propofol, thymol and related compounds, have been shown to act on the GABA(A) receptor. Several compounds with GABAergic activity have displayed neuroprotective effects attributed mainly to the potentiation of GABA(A)-mediated inhibition of synaptic transmission. It has also been found that compounds containing a phenolic OH group can scavenge reactive oxygen species, as in the case of propofol, among others. Thus, the neuroprotective action mechanism of GABAergic phenols would involve both effects, their pharmacological activity on GABA(A) and their intrinsic antioxidant ability. In this context, the study of the antioxidant properties of phenolic compounds included in the present work will enable these capacities to be correlated with their eventual pharmacological activities. The assays chosen in this study included determination of antioxidant ability in homogeneous isotropic systems (DPPH reduction, FRAP and hydrogen peroxide scavenging) and in heterogeneous membrane systems (inhibition of lipid peroxidation of phospholipid SUVs). The comparative evaluation of the results showed some differences between the relative order of antioxidant potency among all assayed compounds determined by using both types of systems. This analysis supports the conclusion that the antioxidant values obtained in homogeneous non-membrane systems, for phenols or other lipophilic compounds, should be revised according to their capacity of interaction with membranes (i.e. Log P in membrane-buffer system) in order to obtain antioxidant potency values more approximate to those actually occurring in biological systems. These results are essential to understand the actual neuroprotective action mechanism exerted by phenolic compounds involving a pharmacological activity, an antioxidant effect or both actions exerted mutually.


Asunto(s)
Antioxidantes/química , Ácidos Grasos/química , GABAérgicos/química , Fármacos Neuroprotectores/química , Fenoles/química , Propofol/química , Antioxidantes/análisis , Antioxidantes/farmacología , Compuestos de Bifenilo/metabolismo , Ácidos Grasos/análisis , Ácidos Grasos/farmacología , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , GABAérgicos/análisis , GABAérgicos/farmacología , Peroxidación de Lípido/efectos de los fármacos , Liposomas , Fármacos Neuroprotectores/análisis , Fármacos Neuroprotectores/farmacología , Oxidación-Reducción , Fenoles/análisis , Fenoles/farmacología , Fosfolípidos , Picratos/metabolismo , Propofol/análisis , Propofol/farmacología , Especies Reactivas de Oxígeno/metabolismo
5.
Headache ; 49(1): 36-44, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19040678

RESUMEN

OBJECTIVE: To evaluate the long-term safety and tolerability of divalproex sodium extended-release in the prophylaxis of migraine headaches in adolescents. BACKGROUND: Divalproex sodium has been approved for migraine prophylaxis in adults. A previous double-blind, placebo-controlled study of the efficacy and safety of divalproex sodium extended-release for prevention of migraine in adolescents was followed by the present long-term extension trial, which was designed to collect additional safety and tolerability data. METHODS: This was a 12-month, Phase 3, open-label extension of a 3-month, double-blind, placebo-controlled, multicenter study of adolescents aged 12 to 17 years with migraine headaches who had either completed the previous study or had discontinued because of lack of efficacy. Subjects from the previous trial who had experienced serious adverse events possibly or probably related to study drug were excluded. Divalproex sodium extended-release 500 mg daily was administered for 15 days then increased to 1000 mg. Study visits were conducted at days 1 and 15 and months 1, 2, 3, 6, 9, and 12. Safety assessments included adverse event collection, laboratory testing, physical and neurological examinations, vital signs, and electrocardiograms, as well as reproductive endocrine analyses for postmenarchal female subjects. Efficacy was evaluated by sequential 4-week migraine headache rates calculated from subjects' headache diaries. RESULTS: A total of 112 subjects enrolled in the trial. The most common adverse events were weight gain (15%), nausea (14%), somnolence (12%), upper respiratory tract infection (11%), increased ammonia (8%), and sinusitis (8%). Five (4%) subjects experienced serious adverse events, and 15 (13%) subjects prematurely discontinued because of an adverse event. Increased ammonia levels were noted in some individuals, and the mean ammonia level for all subjects increased 19.2 microm from baseline. No other clinically significant changes were observed in laboratory values, vital signs, or electrocardiograms. Improvement in mean and median 4-week migraine headache rates occurred by the fourth month and lasted for the duration of the trial. CONCLUSIONS: In this long-term open-label extension study, the safety profile of divalproex sodium extended-release in adolescents with migraine was consistent with that observed in the preceding 3-month, double-blind trial and in previous adult studies. Overall, divalproex sodium extended-release was well-tolerated in adolescents aged 12 to 17 years.


Asunto(s)
GABAérgicos/administración & dosificación , GABAérgicos/análisis , Trastornos Migrañosos/prevención & control , Ácido Valproico/administración & dosificación , Ácido Valproico/efectos adversos , Adolescente , Niño , Preparaciones de Acción Retardada , Método Doble Ciego , Femenino , Humanos , Masculino
6.
Exp Eye Res ; 83(1): 45-50, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16530753

RESUMEN

Experimental models have implicated glutamate in the irreversible damage to retinal cells following retinal detachment. In this retrospective study we investigated a possible role for glutamate and other amino acid neurotransmitters during clinical rhegmatogenous retinal detachment (RRD). Undiluted vitreous samples were obtained from 176 patients undergoing pars plana vitrectomy. The study group consisted of 114 patients (114 eyes) with a rhegmatogenous retinal detachment. Controls included 52 eyes with an idiopathic macular hole or idiopathic epiretinal membrane and 10 eyes with a traction retinal detachment due to proliferative diabetic retinopathy. Vitreous concentrations of glutamate, gamma-aminobutyric acid (GABA), taurine, glycine, and aspartate were determined by high-pressure liquid chromatography (HPLC). Multivariate analysis was used to examine a possible association between amino acid neurotransmitter levels and several clinical variables including visual acuity. The mean vitreous concentration of glutamate in eyes with a rhegmatogenous retinal detachment (16.6 +/- 5.6 microM) was significantly higher as compared to the controls (13.1 +/- 5.2 microM) (P = 0.001). Taurine levels were also increased in RRD, whereas no significant difference could be observed in glycine, aspartate and GABA levels when comparing RRD with controls. A correlation was found between increased vitreous glutamate and a lower pre-operative visual acuity. No association was, however, observed between post-operative visual acuity and the level of any of the five amino acid neurotransmitters. RRD was associated with a significantly increased vitreous glutamate concentration. Using visual acuity as a functional parameter in this study, we could not demonstrate a correlation between vitreous glutamate, or any of the other tested amino acid neurotransmitters and visual outcome.


Asunto(s)
Ácido Glutámico/análisis , Desprendimiento de Retina/metabolismo , Cuerpo Vítreo/química , Ácido Aspártico/análisis , Femenino , GABAérgicos/análisis , Glicina/análisis , Humanos , Masculino , Persona de Mediana Edad , Neurotransmisores/análisis , Desprendimiento de Retina/cirugía , Estudios Retrospectivos , Taurina/análisis , Agudeza Visual/fisiología , Vitrectomía/métodos , Ácido gamma-Aminobutírico/análisis
7.
Neurosci Lett ; 380(3): 340-5, 2005 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-15862914

RESUMEN

There is a significant clinical need to identify novel ligands with high selectivity and potency for GABA(A), GABA(C) and glycine receptor Cl- channels. Two recently developed, yellow fluorescent protein variants (YFP-I152L and YFP-V163S) are highly sensitive to quench by small anions and are thus suited to reporting anionic influx into cells. The aim of this study was to establish the optimal conditions for using these constructs for high-throughput screening of GABA(A), GABA(C) and glycine receptors transiently expressed in HEK293 cells. We found that a 70% fluorescence reduction was achieved by quenching YFP-I152L with a 10 s influx of I- ions, driven by an external I- concentration of at least 50 mM. The fluorescence quench was rapid, with a mean time constant of 3 s. These responses were similar for all anion receptor types studied. We also show the assay is sufficiently sensitive to measure agonist and antagonist concentration-responses using either imaging- or photomultiplier-based detection systems. The robustness, sensitivity and low cost of this assay render it suited for high-throughput screening of transiently expressed anionic ligand-gated channels.


Asunto(s)
Proteínas Bacterianas/química , Bioensayo/métodos , Canales de Cloruro/efectos de los fármacos , Evaluación Preclínica de Medicamentos/métodos , Proteínas Luminiscentes/química , Receptores de GABA-A/efectos de los fármacos , Receptores de Glicina/efectos de los fármacos , Línea Celular , Canales de Cloruro/genética , Canales de Cloruro/metabolismo , Relación Dosis-Respuesta a Droga , GABAérgicos/análisis , GABAérgicos/farmacología , Glicinérgicos/análisis , Glicinérgicos/farmacología , Humanos , Subunidades de Proteína/efectos de los fármacos , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Receptores de GABA-A/genética , Receptores de GABA-A/metabolismo , Receptores de Glicina/genética , Receptores de Glicina/metabolismo , Reproducibilidad de los Resultados
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