Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Arch Kriminol ; 227(5-6): 188-203, 2011.
Artigo em Alemão | MEDLINE | ID: mdl-21805908

RESUMO

For forensic toxicological investigations only whole blood, but no serum is often available. Pharmacokinetic data are helpful for interpreting the results, but most of these studies indicate serum or plasma concentrations. In order to obtain reliable conversion factors which also take intersubject variability into account, the blood/serum ratios (B/S) of oxycodone, morphine, fentanyl, hydromorphone, zopiclone, MDMA, dexamphetamine, alprazolam, risperidone and 9-hydroxyrisperidone were determined by LC-MS/MS using authentic samples. Blood and corresponding serum samples were obtained from driving studies performed with controlled or known dosages of the above drugs. The analytes were analysed in blood and serum and the following mean B/S ratios (relative standard deviations) were determined: oxycodone 1.48 (8.19 %); morphine 1.03 (3.59 %); fentanyl 0.87 (13.9 %); hydromorphone 1.04 (8.11 %); zopiclone 0.89 (16.1 %); MDMA 1.19 (8.04 %); dexamphetamine 0.89 (10.9 %); alprazolam 0.81 (5.84 %); risperidone 0.65 (7.52 %); 9-hydroxyrisperidone 0.73 (12.3 %). These mean values are largely in line with those reported in the literature. The B/S ratios did not appear to depend on partition coefficients, whereas there was strong evidence that B/S ratios decreased with increasing plasma protein binding.


Assuntos
Análise Química do Sangue/métodos , Psicotrópicos/sangue , Soro/química , Xenobióticos/sangue , Cromatografia Líquida de Alta Pressão , Humanos , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem
2.
Clin Chem ; 55(11): 1910-31, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19745062

RESUMO

BACKGROUND: Oral fluid (OF) is an exciting alternative matrix for monitoring drugs of abuse in workplace, clinical toxicology, criminal justice, and driving under the influence of drugs (DUID) programs. During the last 5 years, scientific and technological advances in OF collection, point-of-collection testing devices, and screening and confirmation methods were achieved. Guidelines were proposed for workplace OF testing by the Substance Abuse and Mental Health Services Administration, DUID testing by the European Union's Driving under the Influence of Drugs, Alcohol and Medicines (DRUID) program, and standardization of DUID research. Although OF testing is now commonplace in many monitoring programs, the greatest current limitation is the scarcity of controlled drug administration studies available to guide interpretation. CONTENT: This review outlines OF testing advantages and limitations, and the progress in OF that has occurred during the last 5 years in collection, screening, confirmation, and interpretation of cannabinoids, opioids, amphetamines, cocaine, and benzodiazepines. We examine controlled drug administration studies, immunoassay and chromatographic methods, collection devices, point-of-collection testing device performance, and recent applications of OF testing. SUMMARY: Substance Abuse and Mental Health Services Administration approval of OF testing was delayed because questions about drug OF disposition were not yet resolved, and collection device performance and testing assays required improvement. Here, we document the many advances achieved in the use of OF. Additional research is needed to identify new biomarkers, determine drug detection windows, characterize OF adulteration techniques, and evaluate analyte stability. Nevertheless, there is no doubt that OF offers multiple advantages as an alternative matrix for drug monitoring and has an important role in DUID, treatment, workplace, and criminal justice programs.


Assuntos
Saliva/química , Detecção do Abuso de Substâncias/instrumentação , Detecção do Abuso de Substâncias/métodos , Anfetaminas/análise , Analgésicos Opioides/análise , Benzodiazepinas/análise , Canabinoides/análise , Cocaína/análise , Humanos , Detecção do Abuso de Substâncias/normas
3.
Neurosci Biobehav Rev ; 78: 82-90, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28438467

RESUMO

Drug addiction is a debilitating disorder and its pivotal problem is the high relapse rate. To solve this problem, the aim is to prevent people from becoming addicted in the first place. One of the key questions that is still unanswered is why some people become addicted to drugs and others, who take drugs regularly, do not. In recent years extensive research has been done to untangle the many factors involved in this disorder. Here, we review some of the factors that are related to dopamine, i.e., impulsivity and stress (hormones), and aim to integrate this into a neurobiological model. Based on this, we draw two conclusions: (1) in order to understand the transition from recreational drug use to addiction, we need to focus more on these recreational users; and (2) research should be aimed at finding therapies that can restore inhibitory control/frontal functioning and improve stress resiliency in addicts.


Assuntos
Estimulantes do Sistema Nervoso Central , Comportamento Aditivo , Dopamina , Humanos , Comportamento Impulsivo , Estresse Fisiológico , Estresse Psicológico , Transtornos Relacionados ao Uso de Substâncias
4.
Drug Test Anal ; 8(7): 682-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26097154

RESUMO

Cannabis smoking increases motor vehicle accident risk. Empirically defined cannabinoid detection windows are important to drugged driving legislation. Our aims were to establish plasma cannabinoid detection windows in frequent cannabis smokers and to determine if residual cannabinoid concentrations were correlated with psychomotor performance. Twenty-eight male chronic frequent cannabis smokers resided on a secure research unit for up to 33 days with daily blood collection. Plasma specimens were analyzed for Δ(9) -tetrahydrocannabinol (THC), 11-hydroxy-THC (11-OH-THC), and 11-nor-9-carboxy-THC (THCCOOH) by gas chromatography-mass spectrometry. Critical tracking and divided attention tasks were administered at baseline (after overnight stay to ensure lack of acute intoxication) and after 1, 2, and 3 weeks of cannabis abstinence. Twenty-seven of the twenty-eight participants were THC-positive at admission (median 4.2 µg/L). THC concentrations significantly decreased 24 h after admission, but were still ≥2 µg/L in 16 of the 28 participants 48 h after admission. THC was detected in 3 of 5 specimens on day 30. The last positive 11-OH-THC specimen was 15 days after admission. THCCOOH was measureable in 4 of 5 participants after 30 days of abstinence. Years of prior cannabis use significantly correlated with THC concentrations on admission, and days 7 and 14. Tracking error, evaluated by the Divided Attention Task, was the only evaluated psychomotor assessment significantly correlated with cannabinoid concentrations at baseline and day 8 (11-OH-THC only). Median THC was 0.3 µg/L in 5 chronic frequent cannabis smokers' plasma samples after 30 days of sustained abstinence. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.


Assuntos
Dronabinol/análogos & derivados , Dronabinol/sangue , Fumar Maconha/sangue , Desempenho Psicomotor/efeitos dos fármacos , Psicotrópicos/sangue , Adolescente , Adulto , Idoso , Condução de Veículo , Cannabis , Dronabinol/farmacologia , Humanos , Masculino , Abuso de Maconha/sangue , Pessoa de Meia-Idade , Psicotrópicos/farmacologia , Detecção do Abuso de Substâncias , Adulto Jovem
5.
Psychiatry Res ; 228(3): 907-12, 2015 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-26003508

RESUMO

Some drugs of abuse may produce dissociative symptoms, but this aspect has been understudied. We explored the dissociative potential of three recreational drugs (3,4-methylenedioxymethamphetamine (MDMA), cannabis, and cocaine) during intoxication and compared their effects to literature reports of dissociative states in various samples. Two placebo-controlled studies were conducted. In Study 1 (N=16), participants received single doses of 25, 50, and 100 mg of MDMA, and placebo. In Study 2 (N=21), cannabis (THC 300 µg/kg), cocaine (HCl 300 mg), and placebo were administered. Dissociative symptoms as measured with the Clinician-Administered Dissociative States Scale (CADSS) significantly increased under the influence of MDMA and cannabis. To a lesser extent, this was also true for cocaine. Dissociative symptoms following MDMA and cannabis largely exceeded those observed in schizophrenia patients, were comparable with those observed in Special Forces soldiers undergoing survival training, but were lower compared with ketamine-induced dissociation. Cocaine produced dissociative symptoms that were comparable with those observed in schizophrenia patients, but markedly less than those in Special Forces soldiers and ketamine users. Thus, MDMA and cannabis can produce dissociative symptoms that resemble dissociative pathology. The study of drug induced dissociation is important, because it may shed light on the mechanisms involved in dissociative psychopathology.


Assuntos
Transtornos Relacionados ao Uso de Anfetaminas/psicologia , Canabinoides/administração & dosagem , Transtornos Relacionados ao Uso de Cocaína/psicologia , Cocaína/efeitos adversos , Transtornos Dissociativos/induzido quimicamente , Abuso de Maconha/psicologia , N-Metil-3,4-Metilenodioxianfetamina/efeitos adversos , Adulto , Estudos Cross-Over , Transtornos Dissociativos/diagnóstico , Transtornos Dissociativos/psicologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Esquizofrenia/induzido quimicamente , Inquéritos e Questionários
6.
PLoS One ; 8(1): e53127, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23301031

RESUMO

BACKGROUND: The present study assessed psychomotor function in chronic, daily cannabis smokers during 3 weeks continuously monitored abstinence on a secure research unit. We hypothesized that psychomotor performance would improve during abstinence of chronic, daily cannabis smokers. METHODOLOGY/PRINCIPAL FINDINGS: Performance on the critical tracking (CTT) and divided attention (DAT) tasks was assessed in 19 male chronic, daily cannabis smokers at baseline and after 8, 14-16 and 21-23 days of continuously monitored abstinence. Psychomotor performance was compared to a control group of non-intoxicated occasional drug users. Critical frequency (λ(c)) of the CTT and tracking error and control losses of the DAT were the primary outcome measures. Results showed that chronic cannabis smokers' performance on the CTT (p<0.001) and the DAT (p<0.001) was impaired during baseline relative to the comparison group. Psychomotor performance in the chronic cannabis smokers improved over 3 weeks of abstinence, but did not recover to equivalent control group performance. CONCLUSIONS/SIGNIFICANCE: Sustained cannabis abstinence moderately improved critical tracking and divided attention performance in chronic, daily cannabis smokers, but impairment was still observable compared to controls after 3 weeks of abstinence. Between group differences, however, need to be interpreted with caution as chronic smokers and controls were not matched for education, social economic status, life style and race.


Assuntos
Atenção/efeitos dos fármacos , Abuso de Maconha/fisiopatologia , Desempenho Psicomotor/efeitos dos fármacos , Adulto , Cannabis , Estudos de Casos e Controles , Cognição , Dronabinol/farmacologia , Feminino , Humanos , Masculino , Fumar Maconha , Reprodutibilidade dos Testes , Fatores de Tempo , Adulto Jovem
7.
Psychopharmacology (Berl) ; 222(3): 367-76, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21952668

RESUMO

RATIONALE: Experimental research has shown that 3,4-methylenedioxymethamphetamine (MDMA) can improve some psychomotor driving skills when administered during the day. In real life, however, MDMA is taken during the night, and driving may likely occur early in the morning after a night of "raving" and sleep loss. OBJECTIVES: The present study assessed the effects of MDMA on road-tracking and car-following performance in on-the-road driving tests in normal traffic. METHODS: Sixteen recreational MDMA users participated in a randomized double-blind placebo-controlled four-way cross-over design. They received single, evening doses of 0, 25, 50, and 100 mg MDMA on separate occasions. Actual driving tests were conducted in the evening when MDMA serum concentrations were maximal and in the morning after a night of sleep loss. RESULTS: The primary measure of driving, i.e., standard deviation of lateral position (SDLP, a measure of weaving) was significantly increased during driving tests in the morning in all treatment conditions, irrespective of MDMA dose and concentration. The increments in SDLP were of high clinical relevance and comparable to those observed for alcohol at blood alcohol concentrations >0.8 mg/mL. These impairments were primarily caused by sleep loss. CONCLUSIONS: In general, MDMA did not affect driving performance nor did it change the impairing effects of sleep loss. It is concluded that MDMA cannot compensate for the impairing effects of sleep loss and that drivers who are under the influence of MDMA and sleep deprived are unfit to drive.


Assuntos
Condução de Veículo , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Desempenho Psicomotor/efeitos dos fármacos , Saliva/metabolismo , Privação do Sono/psicologia , Adulto , Distribuição Binomial , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Mucosa Bucal/metabolismo , N-Metil-3,4-Metilenodioxianfetamina/farmacocinética
8.
J Anal Toxicol ; 36(6): 405-12, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22589524

RESUMO

Δ9-Tetrahydrocannabinol (THC) is the illicit drug most frequently observed in accident and driving under the influence of drugs investigations. Whole blood is often the only available specimen collected during such investigations, yet few studies have examined relationships between cannabis effects and whole blood concentrations following cannabis smoking. Nine male and one female heavy, chronic cannabis smokers resided on a closed research unit and smoked ad libitum one 6.8% THC cannabis cigarette. THC, 11-hydroxy-THC and 11-nor-9-carboxy-THC were quantified in whole blood and plasma. Assessments were performed before and up to 6 h after smoking, including subjective [visual analog scales (VAS) and Likert scales], physiological (heart rate, blood pressure and respirations) and psychomotor (critical-tracking and divided-attention tasks) measures. THC significantly increased VAS responses and heart rate, with concentration-effect curves demonstrating counter-clockwise hysteresis. No significant differences were observed for critical-tracking or divided-attention task performance in this cohort of heavy, chronic cannabis smokers. The cannabis influence factor was not suitable for quantifying psychomotor impairment following cannabis consumption and was not precise enough to determine recent cannabis use with accuracy. These data inform our understanding of impairment and subjective effects following acute smoked cannabis and interpretation of whole blood cannabinoid concentrations in forensic investigations.


Assuntos
Dronabinol/sangue , Fumar Maconha/efeitos adversos , Fumar Maconha/sangue , Desempenho Psicomotor/efeitos dos fármacos , Detecção do Abuso de Substâncias , Adolescente , Adulto , Biotransformação , Estudos de Coortes , Dronabinol/análogos & derivados , Dronabinol/química , Dronabinol/farmacocinética , Tolerância a Medicamentos , Feminino , Toxicologia Forense/métodos , Frequência Cardíaca/efeitos dos fármacos , Humanos , Limite de Detecção , Masculino , Fumar Maconha/metabolismo , Pessoa de Meia-Idade , Estereoisomerismo , Adulto Jovem
9.
PLoS One ; 7(7): e40187, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22808116

RESUMO

UNLABELLED: MDMA induces positive mood and increases impulse control during intoxication, but only a few studies on the neuropharmacological mechanisms underlying these processes have been conducted. It was hypothesized that pretreatment with 5-HT(1) and 5-HT(2) receptor blockers would prevent MDMA effects on mood and impulsivity. Subjects (N = 17) participated in a double-blind, placebo controlled, within-subject design involving 6 experimental conditions consisting of pretreatment (T1) and treatment (T2). T1 preceded T2 by 30 minutes. T1-T2 combinations were: placebo-placebo, 20 mg pindolol-placebo, 50 mg ketanserin-placebo, placebo-75 mg MDMA, 20 mg pindolol-75 mg MDMA and 50 mg ketanserin-75 g MDMA. Subjects completed a Profile of Mood States (POMS) questionnaire and several impulsivity tasks (Stop signal task, Matching familiar figures task, Cue dependent reversal learning task) at 1.5 hrs post-treatment. MDMA alone increased both positive (vigor, arousal, friendliness, elation, positive mood) and negative affect (anxiety, confusion) as assessed by the POMS questionnaire. MDMA also increased stop reaction time in the Stop signal task and reaction time in the Matching familiar figures task. Pretreatment with ketanserin blocked MDMA effects on positive affect, but not negative affect. Ketanserin did not influence the effects of MDMA on impulsivity. Pindolol did not interact with MDMA on any of the measures. In conclusion, 5-HT(2) receptors mediate positive moods induced by MDMA but not negative moods or impulsivity. 5-HT(1) receptors do not appear to be involved in MDMA effects on mood and impulse control. TRIAL REGISTRATION: Nederlands Trial Register NTR2352.


Assuntos
Afeto/efeitos dos fármacos , Comportamento Impulsivo/tratamento farmacológico , Comportamento Impulsivo/metabolismo , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Receptores 5-HT1 de Serotonina/metabolismo , Receptores 5-HT2 de Serotonina/metabolismo , Adulto , Feminino , Humanos , Aprendizagem/efeitos dos fármacos , Modelos Lineares , Masculino , N-Metil-3,4-Metilenodioxianfetamina/administração & dosagem , N-Metil-3,4-Metilenodioxianfetamina/sangue , Antagonistas do Receptor 5-HT1 de Serotonina/farmacologia , Antagonistas do Receptor 5-HT1 de Serotonina/uso terapêutico , Inquéritos e Questionários , Análise e Desempenho de Tarefas , Adulto Jovem
10.
Addiction ; 107(10): 1837-44, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22553980

RESUMO

AIMS: The acute and chronic effects of dronabinol [medicinal Δ(9) -tetrahydrocannabinol (THC)] on actual driving performance and the Standard Field Sobriety Test (SFST) were assessed. It was hypothesized that occasional users would be impaired on these tests and that heavy users would show less impairment due to tolerance. DESIGN, SETTING AND PARTICIPANTS: Double-blind, placebo-controlled, randomized, three-way cross-over study. Twelve occasional and 12 heavy cannabis users (14 males/10 females) received single doses of placebo, 10 and 20 mg dronabinol. MEASUREMENTS: Standard deviation of lateral position (SDLP; i.e. weaving) is the primary measure of road-tracking control. Time to speed adaptation (TSA) is the primary reaction-time measure in the car-following test. Percentage of impaired individuals on the SFST and subjective high on a visual analogue scale were secondary measures. FINDINGS: Superiority tests showed that SDLP (P = 0.008) and TSA (P = 0.011) increased after dronabinol in occasional users. Equivalence tests demonstrated that dronabinol-induced increments in SDLP were bigger than impairment associated with BAC of 0.5 mg/ml in occasional and heavy users, although the magnitude of driving impairment was generally less in heavy users. The SFST did not discriminate between conditions. Levels of subjective high were comparable in occasional and heavy users. CONCLUSIONS: Dronabinol (medicinal tetrahydrocannabinol) impairs driving performance in occasional and heavy users in a dose-dependent way, but to a lesser degree in heavy users due possibly to tolerance. The Standard Field Sobriety Test is not sensitive to clinically relevant driving impairment caused by oral tetrahydrocannabinol.


Assuntos
Condução de Veículo , Dronabinol/farmacologia , Abuso de Maconha/psicologia , Desempenho Psicomotor/efeitos dos fármacos , Psicotrópicos/farmacologia , Administração Oral , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Dronabinol/administração & dosagem , Feminino , Humanos , Masculino , Abuso de Maconha/diagnóstico , Psicotrópicos/administração & dosagem , Detecção do Abuso de Substâncias , Adulto Jovem
11.
PLoS One ; 6(9): e24253, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21935391

RESUMO

Neuropsychological and imaging studies have shown that the left supramarginal gyrus (SMG) is specifically involved in processing spatial terms (e.g. above, left of), which locate places and objects in the world. The current fMRI study focused on the nature and specificity of representing spatial language in the left SMG by combining behavioral and neuronal activation data in blind and sighted individuals. Data from the blind provide an elegant way to test the supramodal representation hypothesis, i.e. abstract codes representing spatial relations yielding no activation differences between blind and sighted. Indeed, the left SMG was activated during spatial language processing in both blind and sighted individuals implying a supramodal representation of spatial and other dimensional relations which does not require visual experience to develop. However, in the absence of vision functional reorganization of the visual cortex is known to take place. An important consideration with respect to our finding is the amount of functional reorganization during language processing in our blind participants. Therefore, the participants also performed a verb generation task. We observed that only in the blind occipital areas were activated during covert language generation. Additionally, in the first task there was functional reorganization observed for processing language with a high linguistic load. As the visual cortex was not specifically active for spatial contents in the first task, and no reorganization was observed in the SMG, the latter finding further supports the notion that the left SMG is the main node for a supramodal representation of verbal spatial relations.


Assuntos
Idioma , Córtex Visual/fisiologia , Pessoas com Deficiência Visual , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
12.
Psychopharmacology (Berl) ; 209(1): 69-76, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20084368

RESUMO

INTRODUCTION: 3,4-methylenedioxymethamphetamine (MDMA) is known to improve psychomotor function and mood when measured during daytime. However, MDMA users tend to take this drug at dance parties while staying awake for prolonged periods of time. SUBJECTS AND METHODS: This study was designed to assess dose-related residual effects of MDMA on psychomotor function and mood after a night without sleep. Sixteen recreational MDMA users received single doses of 25, 50, and 100 mg MDMA in a randomized, double-blind, placebo-controlled cross-over study. RESULTS: Results showed that sleep loss significantly impaired psychomotor function. MDMA generally did not affect performance but did improve rapid information processing at the highest dose in the morning after administration. In the evening, MDMA also increased subjective ratings of positive mood at every dose and subjective arousal at the highest dose. These subjective effects were no longer present after a night of sleep loss. DISCUSSION: It is concluded that sleep deprivation impairs psychomotor function and that stimulant effects of MDMA are not sufficient to compensate for this impairment.


Assuntos
Alucinógenos/toxicidade , N-Metil-3,4-Metilenodioxianfetamina/toxicidade , Desempenho Psicomotor/efeitos dos fármacos , Afeto/efeitos dos fármacos , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Alucinógenos/administração & dosagem , Humanos , Masculino , N-Metil-3,4-Metilenodioxianfetamina/administração & dosagem , Privação do Sono , Fatores de Tempo , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA