RESUMO
Adherence is a major factor in the effectiveness of the injectable extended-release naltrexone as a relapse prevention treatment in opioid use disorder. We examined the value of a variant of the Go/No-go paradigm in predicting extended-release naltrexone adherence in 27 detoxified opioid use disorder patients who were offered up to 3 monthly extended-release naltrexone injections. Before extended-release naltrexone, participants performed a Go/No-go task that comprised positively valenced Go trials and negatively valenced No-go trials during a functional magnetic resonance imaging scan. Errors of commission and neural responses to the No-go vs Go trials were independent variables. Adherence, operationalized as the completion of all 3 extended-release naltrexone injections, was the outcome variable. Fewer errors of commission and greater left accumbal response during the No-go vs Go trials predicted better adherence. These findings support the clinical potential of the behavioral and neurophysiological correlates of response inhibition in the prediction of extended-release naltrexone treatment outcomes in opioid use disorder.
Assuntos
Adesão à Medicação , Naltrexona/administração & dosagem , Antagonistas de Entorpecentes/administração & dosagem , Núcleo Accumbens/efeitos dos fármacos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Desempenho Psicomotor/efeitos dos fármacos , Adolescente , Adulto , Preparações de Ação Retardada/administração & dosagem , Feminino , Humanos , Injeções Intramusculares , Imageamento por Ressonância Magnética/métodos , Masculino , Adesão à Medicação/psicologia , Núcleo Accumbens/diagnóstico por imagem , Núcleo Accumbens/fisiologia , Transtornos Relacionados ao Uso de Opioides/diagnóstico por imagem , Transtornos Relacionados ao Uso de Opioides/psicologia , Estimulação Luminosa/métodos , Valor Preditivo dos Testes , Desempenho Psicomotor/fisiologia , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: Cocaine and amphetamine-regulated transcript (CART) is an endogenous antioxidant present since the embryonic period. CART is activated by high levels of dopamine and might be of interested in understanding the changes in the REDOX system associated with crack/cocaine intake. The goal of this study was to determine whether exposure to crack in utero is associated with increased CART levels. METHODS: In this cross-sectional study with consecutive sampling, we compared the umbilical cord blood (UCB) CART levels (µg/mL) of newborns exposed to crack/cocaine in utero (EN, n = 57) to levels in non-exposed newborns (NEN, n = 99). In addition, we compared serum CART levels between EN and NEN mothers, in the immediate postpartum period. Potential confounders, such as perinatal data (e.g., weight, Apgar, etc.), psychopathology (DSM-IV), and use of drugs other than crack (ASSIST) were assessed. RESULTS: According to general linear model analysis, the adjusted mean CART was significantly higher in EN (0.180, 95% CI 0.088-0.272) than in NEN (0.048, 95% CI 0.020-0.076; p < 0.002; d = 0.68). The difference in CART levels between EN and NEN mothers was not significant (p ≥ 0.05). CONCLUSION: The increase in CART levels in EN UBC suggests a response to crack/cocaine-induced oxidative stress during gestational period, as a potential attempt of neuroprotection. In adult women in puerperium, however, this endogenous antioxidant recruitment does not seem to operate.
Assuntos
Cocaína Crack/farmacologia , Sangue Fetal/metabolismo , Proteínas do Tecido Nervoso/sangue , Adulto , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Masculino , Período Pós-Parto , GravidezRESUMO
Methylphenidate (MPH) is the most commonly prescribed treatment for attention-deficit/hyperactivity disorder (ADHD). The therapeutic mechanisms of MPH are not, however, fully understood. We studied the effects of MPH on brain activity in male children and adolescents with ADHD, using the blood flow radiotracer technetium-99m ethyl cysteinate dimer ((99m)Tc-ECD) and single-photon emission tomography (SPET). The study was randomized, double blind, and placebo controlled (MPH group, n=19; placebo group, n=17), Radiotracer was administered during the performance of the Continuous Performance Test and before and after 4 days of MPH treatment. Statistical parametric mapping (SPM99) analysis showed a significant reduction in regional cerebral blood flow in the left parietal region in the MPH group compared with the placebo group (P<0.05, corrected for multiple comparisons). Our findings suggest that the posterior attentional system, which includes the parietal cortex, may have a role in the mediation of the therapeutic effects of MPH in ADHD.