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1.
Exp Clin Psychopharmacol ; 26(4): 329-334, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29878800

RESUMO

Addiction is characterized as a chronic debilitating disease. One devastating feature of addiction is the susceptibility of relapse (40-60%) after stretches of abstinence. One theory that may account for relapse suggests that drug cues (e.g., paraphernalia) may increase stress hormones, and this may prompt relapse. Repeatedly pairing a neutral cue with a reward is commonly utilized to measure what subjects learn about a cue that is predictive of reward. Research has shown that animals that attend to a cue more than to the reward (sign trackers) may be more vulnerable to drug addiction. Additionally, research has shown that sign tracking is associated with an increase in corticosterone, a primary stress hormone. PT150 is a novel glucocorticoid receptor antagonist that moderates the release of corticosterone. In the current experiment, it was hypothesized that subjects given repeated administration of PT150 would reduce sign tracking compared to subjects given placebo. Time spent (in seconds) near a cue that predicts reward (conditional stimulus) served as a measure of sign tracking, and PT150 or placebo was administered following sign tracking. An independent-samples t test revealed that subjects that received PT150 had reduced time spent near the conditioned stimulus compared to controls. Given the devastating effects of drug addiction, identification of a potential pharmacological intervention in the reduction of relapse would be of great value. Therefore, future research is needed to validate the use of PT150 in reducing behaviors associated with drug addiction. (PsycINFO Database Record


Assuntos
Comportamento Aditivo/tratamento farmacológico , Sinais (Psicologia) , Norpregnanos/farmacologia , Receptores de Glucocorticoides/antagonistas & inibidores , Receptores de Glucocorticoides/fisiologia , Recompensa , Animais , Comportamento Aditivo/psicologia , Condicionamento Clássico/efeitos dos fármacos , Condicionamento Clássico/fisiologia , Coturnix , Masculino , Motivação/efeitos dos fármacos , Motivação/fisiologia , Norpregnanos/química , Norpregnanos/uso terapêutico , Ratos Sprague-Dawley
2.
Acta Crystallogr C ; 65(Pt 5): o214-6, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19407419

RESUMO

In the title compound, C(23)H(34)O(4), which is an intermediate in the synthesis of pregnane derivatives with a modified skeleton that show potent abortion-inducing activity, the conformation of ring B is close to half-chair due to the presence of both the C=C double bond and the axial 5beta-methyl group. Rings A and C have conformations close to chair, while ring D has a twisted conformation around the bridgehead C-C bond. Molecules are hydrogen bonded via the hydroxyl and acetoxy groups into infinite chains. Quantum-mechanical ab initio Roothan Hartree-Fock calculations show that crystal packing might be responsible for the low values of the angles between rings A and B, and between ring A and rings C and D, as well as for a different steric position of the methyl ketone side chain compared to the geometry of the free molecule.


Assuntos
Abortivos Esteroides/química , Cristalografia por Raios X , Norpregnanos/química , Pregnanos/química , Abortivos Esteroides/síntese química , Feminino , Humanos , Ligação de Hidrogênio , Conformação Molecular , Norpregnanos/síntese química , Gravidez , Pregnanos/síntese química , Teoria Quântica
3.
Nat Prod Res ; 20(12): 1074-81, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17201044

RESUMO

The microbial transformation of levonorgestrel (1) by Cunningham elegans resulted in the formation of five hydroxylated metabolites, 13-ethyl-10beta, 17beta-dihydroxy-18,19-dinor-17alpha-pregn-4-en-20-yn-3-one(2), 13-ethyl-6beta,17beta-dihydroxy-18,19-dinor-17alpha-pregn-4-en-20-yn-3-one (3) 13-ethyl 6beta, 10beta, 17beta-trihydroxy-18,19-dinor-17alpha-pregn-4-en-20-yn-3-one (4) 13-ethyl-15alpha-17beta-dihydroxy-18,19-dinor-17alpha-pregn-4-en-20-yn-3-one (5) and 13-ethyl-11alpha, 17beta-dihydroxy-18,19-dinor-17alpha-pregn-4en-20-yn-3-one. The fermentation of one with Rhizopus stolonifer, Fusarium lini and Curvularia lunata afforded compound 2 as a major metabolise. These metabolites were structurally characterized on the basis of spectroScopic techniques. Metabolite 6 was identified as a new compound. Compounds 2 2 ad 5 displayed inhibitory activity against the acetylcholinesterase ( AChE, EC. 3.1.1.7) with IC50 values of 79.2 and 24.5 microM, respectively. The metabolites 2 and 5 also showed inhibitory activity against the butyryLcholinesterase ( BChE, E.C 3.1.1.8) with IC50 values ranging between 9.4 and 309.8 microM.


Assuntos
Inibidores da Colinesterase/metabolismo , Cunninghamella/metabolismo , Levanogestrel/química , Levanogestrel/metabolismo , Norpregnanos/química , Norpregnanos/metabolismo , Butirilcolinesterase/metabolismo , Fermentação , Hidroxilação , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Análise Espectral
4.
Fresenius J Anal Chem ; 368(4): 384-8, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11227508

RESUMO

delta4-3-Ketosteroids exhibit an intensive negative Cotton effect on the circular dichroism (CD) spectra in the wavelength range for the n-pi* electronic transition (270-350 nm). With hydroxylamine hydrochloride, delta4-3-ketosteroid compounds can be transformed into oxime derivatives. Following oxime formation, positive ellipticity with low intensity can be registered in this wavelength range. The quantitative determination of delta4-3-ketosteroids is based on the considerable difference between the ellipticities before and after oxime formation. The difference ellipticity for the six ketosteroids examined (norethisterone, levonorgestrel, levonorgestrel acetate, methyltestosterone, testosterone phenylpropionate, nortestosterone phenylpropionate) varies linearly with the concentration in the interval 6 x 10(-6)-3 x 10(-3) mol/L. The method can be well applied to determination of delta4-3-ketosteroid contamination of norgestimate [(+)-13-ethyl-17-hydroxy-18,19-dinor-17alpha-pregn4-en-20-yn-3-one oxime acetate]; 0.02-10% impurity can be measured.


Assuntos
Cetosteroides/análise , Oximas/análise , Oximas/síntese química , Dicroísmo Circular , Contaminação de Medicamentos , Hormônios Esteroides Gonadais/análise , Hormônios Esteroides Gonadais/química , Hormônios Esteroides Gonadais/normas , Cetosteroides/química , Cetosteroides/normas , Norpregnanos/análise , Norpregnanos/química , Norpregnanos/normas , Oximas/química , Testosterona/análise , Testosterona/química , Testosterona/normas
5.
J Nat Prod ; 62(2): 318-20, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10075773

RESUMO

Two new norpregnane glycosides, 19-norpregna-1,3,5(10), 20-tetraen-3-O-alpha-fucopyranoside (3) and 19-norpregna-1,3,5(10), 20-tetraen-3-O-beta-arabinopyranoside (4), were isolated from the soft coral Scleronephthya pallida, along with two known steroids, pregna-1,20-dien-3-one (1) and 19-norpregna-1,3,5(10), 20-tetraen-3-ol (2). 19-Norpregna-1,3,5(10), 20-tetraen-3-O-alpha-fucopyranoside (3) exhibits moderate antimalarial and cytotoxic activities. The chemical structures of 1-4 were elucidated from spectroscopic data.


Assuntos
Antimaláricos/isolamento & purificação , Cnidários/química , Glicosídeos/isolamento & purificação , Norpregnanos/isolamento & purificação , Animais , Antimaláricos/química , Antimaláricos/farmacologia , Sequência de Carboidratos , Glicosídeos/química , Glicosídeos/farmacologia , Norpregnanos/química , Norpregnanos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Análise Espectral
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