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1.
J Neural Transm (Vienna) ; 108(6): 747-53, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11478424

RESUMO

Determinants of individual differences in sleep-wake cycles and vigilance are being recognized as major factors of influence in both physical and mental health. Alterations of an accustomed circadian sleep-wake rhythm are commonly seen in the early stages of the majority of psychiatric disorders and, by themselves, predispose to significant morbidity even in the absence of an underlying illness. While it is well known that disruptions of sleep respond favourably to benzodiazepines, agents which have been prescribed for insomnia since their industrial synthesis in the early 1960s, little attention has been paid to putative central nervous system effects of naturally occurring benzodiazepines. These molecules were found in various nutritive plants and have been quantified in human brain and peripheral blood of drug-naive individuals at trace amounts. There is agreement that elevated concentrations of naturally occurring benzodiazepines participate in the complex pathophysiology of hepatic encephalopathy, a condition asssociated with progressive impairment of consciousness and, ultimately, coma. In the present study, we address the relationship between naturally occurring benzodiazepines and time-of-day effects on the behavior of healthy subjects.


Assuntos
Benzodiazepinas/sangue , Relógios Biológicos/genética , Adulto , Química Encefálica/genética , Feminino , Humanos , Masculino , Polissonografia , Receptores de GABA-A/metabolismo , Sono REM/genética , Vigília/genética , Ácido gama-Aminobutírico/metabolismo
2.
Eur Arch Psychiatry Clin Neurosci ; 250(4): 194-202, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11009072

RESUMO

Naturally occurring benzodiazepines (BZDs) were first detected in mammalian tissues in 1986. They comprise a variety of 1,4-benzodiazepines corresponding to drugs commercially available for the treatment of anxiety disorders, sleep disturbances and epileptic seizures. Several biosynthetic pathways leading to the formation of BZDs are currently being discussed and have led to the proposition of possible precursor molecules. For years, the identification of naturally occurring BZDs in mammalian organisms was mostly confined to post mortem CNS material for sensitivity reasons. While radioimmunoassay and radioreceptor assay techniques have been tentatively applied to quantitations of genuine BZDs from human milk and cerebrospinal fluid, accurate measurements in peripheral blood have only recently become accessible, e. g., by gas chromatography/selected ion monitoring-mass spectrometry (GC/SIM-MS). This review summarizes existing evidence of benzodiazepines' occurrence in nature and discusses implications for neuropsychiatric disorders.


Assuntos
Benzodiazepinas/metabolismo , Animais , Ansiedade/tratamento farmacológico , Benzodiazepinas/uso terapêutico , Encéfalo/metabolismo , Cromatografia Líquida de Alta Pressão , Epilepsia/tratamento farmacológico , Flumazenil/uso terapêutico , Moduladores GABAérgicos/uso terapêutico , Antagonistas de Receptores de GABA-A , Encefalopatia Hepática/metabolismo , Humanos , Transtornos da Memória/tratamento farmacológico , Neuroglia/metabolismo , Neurônios/metabolismo , Plantas/metabolismo , Radioimunoensaio , Receptores de GABA-A/biossíntese , Transtornos do Sono-Vigília/tratamento farmacológico
3.
Biochem Biophys Res Commun ; 269(1): 290-5, 2000 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-10694515

RESUMO

Sterile cultivated plant cell tissues and cell regenerates of several species were tested for their binding affinity to the central human benzodiazepine receptor. Binding activity was found in extracts of Artemisia dracunculus cell tissue (IC(50) = 7 microg/ml) and, to a lesser extent, in plant regenerates of potato herb (Solanum tuberosum). Preparative HPLC led to the isolation of fractions with a significant displacing potency in the benzodiazepine receptor binding assay. Using on-line HPLC-electrospray-tandem mass spectrometry (HPLC-ESI-MS/MS) in the "selected reaction monitoring" (SRM) mode, delorazepam and temazepam were found in amounts of about 100 to 200 ng/g cell tissue of Artemisia dracunculus, whereas sterile potato herb contained temazepam and diazepam ranging approximately from 70 to 450 ng/g cell tissue. It is the first report on the endogenous formation of benzodiazepines by plant cells, as any interaction of microorganisms and environmental factors was excluded.


Assuntos
Artemisia/metabolismo , Benzodiazepinas/metabolismo , Plantas Medicinais , Solanum tuberosum/metabolismo , Benzodiazepinas/química , Benzodiazepinas/isolamento & purificação , Ligação Competitiva , Córtex Cerebral/metabolismo , Cromatografia Líquida de Alta Pressão , Diazepam/química , Diazepam/isolamento & purificação , Diazepam/metabolismo , Humanos , Técnicas In Vitro , Espectrometria de Massas , Receptores de GABA-A/metabolismo , Temazepam/química , Temazepam/isolamento & purificação , Temazepam/metabolismo
4.
J Agric Food Chem ; 47(12): 5178-83, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10606591

RESUMO

Extracts obtained by XAD solid-phase extraction of apple juice and cider were separated by liquid chromatography on silica gel. Several new 1,3-dioxanes including the known 2-methyl-4-pentyl-1,3-dioxane and 2-methyl-4-[2'(Z)-pentenyl]-1,3-dioxane, were identified in the nonpolar fractions by GC/MS analysis and confirmed by chemical synthesis. The enantioselective synthesis of the stereoisomers of the 1,3-dioxanes was performed using (R)- and (R,S)-octane-1,3-diol and (R)- and (R,S)-5(Z)-octene-1,3-diol as starting material. Comparison with the isolated products indicated that the natural products consisted of a mixture of (2S,4R) and (2R,4R) stereoisomers in the ratio of approximately 10:1, except for 1,3-dioxanes generated from acetone and 2-butanone. It is assumed that the 1, 3-dioxanes are chemically formed in the apples and cider from the natural apple ingredients (R)-octane-1,3-diol, (R)-5(Z)-octene-1, 3-diol, (3R,7R)- and (3R,7S)-octane-1,3,7-triol, and the appropriate aldehydes and ketones, which are produced either by the apples or by yeast during fermentation of the apple juice.


Assuntos
Bebidas/análise , Dioxanos/isolamento & purificação , Manipulação de Alimentos , Rosales , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Espectroscopia de Ressonância Magnética
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