RÉSUMÉ Reprenant les trois argumentaires des rapports divergents de la commission le Dain de 1972, soit le moralisme juridique pour le maintien de la prohibition du cannabis, le paternalisme juridique pour la décriminalisation de sa possession simple et le libéralisme juridique pour sa légalisation, cette thèse mobilise ce triptyque inspiré par trois philosophes juridiques à l’aide de l’analyse de contenu afin de voir comment ces arguments se sont manifestés à nouveau dans le processus parlementaire d’adoption du projet de loi C-45 ayant mené à la légalisation du cannabis au Canada. De plus, elle mobilise aussi le concept de la rationalité pénale moderne dans le but de comprendre l’approbation chez les différents acteurs d’avoir recours au pénal dans ce projet de loi en acceptant l’inclusion de deux nouvelles infractions criminelles passibles de 14 ans d’emprisonnement. Ces infractions visent un adulte qui ferait participer un mineur au marché illégal de cannabis, ou encore vendrait ou donnerait du cannabis à un mineur. La clarification de ce paradoxe était importante considérant que ce projet de loi fut essentiellement justifié par ceux qui y étaient favorables sur la volonté de diminuer un recours au droit criminel identifié comme inefficace à la réduction de la consommation du cannabis, tout en créant de nouvelles infractions pénales pour éviter son accès aux mineurs. Les résultats de cette thèse ont démontré que si des philosophies de type moraliste et paternaliste demeurent bien présentes lors des débats parlementaires sur C-45, le libéralisme juridique l’est aussi, mais tend fortement à disparaitre dès qu’arrive la question de la santé et de la sécurité des mineurs. De plus, si la durée des nouvelles peines demeure contestée par certains, il semble qu’en aucun temps le recours au pénal en guise d’outil de gestion de ces infractions ne soit remis en question, ce qui s’est traduit entre autres par l’absence totale de débats en ce qui a trait à l’utilisation d’un mineur dans le marché illégal de cannabis. Ce dernier point pourrait s’expliquer par une volonté de réforme par contraste qui vise une meilleure efficacité du système en place plutôt qu’une réforme générative qui cherche l’innovation et le renouveau, ce qui aurait demandé la remise en question du paradigme dominant sur certaines drogues actuellement illégales, soit la prohibition. ABSTRACT By taking up the three arguments of the divergent reports of the Le Dain Commission of 1972, the legal moralism in favor of the maintenance of the prohibition of cannabis, the legal paternalism for the decriminalization of tis simple possession and the legal liberalism in favor of legalization, this thesis mobilize this triptych inspired by three legal philosophers by using content analysis in parliamentary debates to see how these arguments manifested themselves again in the process of passing Bill C-45 which led to the legalization of cannabis in Canada. Furthermore, it also mobilizes the concept of modern criminal rationality in order to understand the approval for the various actors to use the criminal law in this bill by accepting the inclusion of two new criminal offenses punishable by 14 years of imprisonment. These offenses target an adult who would involve a minor in the illegal cannabis market, or sell or give cannabis to a minor. The clarification of this paradox was important considering that this bill was essentially justified by those who were in favor of reducing the use of criminal law identified as ineffective in reducing the use of cannabis, while creating new offenses to prevent its access from minors. The results of this thesis have shown that while moralistic and paternalistic philosophies remain very much present during parliamentary debates on Bill C-45, legal liberalism is also present, but tends to disappear as soon as the question of health and safety of minors come up. Moreover, while the duration of the new sentences is still disputed by some, it appears that at no time is the use of the criminal law as a tool for managing these offenses is questioned, which has resulted in the total lack of debate regarding the use of a minor in the illegal cannabis market. This last point could be explained by a desire for the adoption of a reform by contrast which aims to improve the effectiveness of the system in place rather than a generative reform that seeks innovation and renewal, which would have asked a questioning of the dominant paradigm on some currently illegal drugs, the prohibition in itself.

Background: The current study examines the association of perceived racial and social class discrimination with cannabis involvement among Black youth and young adults. Methods: This secondary analysis used data from the Missouri Family Study (MOFAM), a high-risk longitudinal family study of alcohol use disorder, oversampled for Black families. Offspring (n = 806) and their mothers were interviewed by telephone. Cox proportional hazards regression analyzes were used to examine associations of racial and social class discrimination (experienced by offspring and their mothers) with offspring cannabis involvement. Two stages of cannabis involvement were analyzed: timing of 1) initiation and 2) transition from initiation to first cannabis use disorder (CUD) symptom. Results: The study found that offspring report of experiencing racial (HR: 1.28, CI: 1.01–1.62) and social class discrimination (HR: 1.45, CI: 1.14–1.84) were associated with cannabis initiation in our fully adjusted model. Mothers’ report of discrimination predicted a lower hazard of cannabis initiation among offspring (HR: 0.79, CI: 0.64–0.98). Offspring social class discrimination (HR: 2.45, CI: 1.71–3.51) predicted an increased hazard of transition from initiation to first CUD symptom, while offspring racial discrimination (HR: 0.57, CI: 0.39–0.85) was associated with lower hazard of transition in our fully adjusted model. Conclusions: As rates for cannabis use among Black youth are disproportionately rising, there is a critical need to identify pathways to its use among Black youth. These findings suggest racial and social class discrimination may be important targets in efforts to prevent cannabis involvement among Black youth and emerging adults.

No description available.

The association between extent of chronic cannabis use (CCU-extent) and cognitive impairment among adolescents has been the subject of controversial debate. Linking DNA methylation to CCU-extent could help to understand cannabis associated changes in cognitive performance. We analyzed cognitive task performances, CpG methylation in peripheral whole-blood samples and self-reported past-year CCU-extent of n = 18 adolescents (n = 9 psychiatric outpatients with chronic cannabis use (CCU), n = 9 without) who were matched for age, gender and psychiatric disorders. Patients with CCU were at least 24 h abstinent when cognitive tasks were performed. A Principal Component Analysis (PCA) was carried out to identify group differences in whole genome DNA methylation. Mediation analyses were performed between CCU-extent associated CpG sites and CCU-extent associated variables of cognitive tasks. PCA results indicated large differences in whole genome DNA methylation levels between the groups that did not reach statistical significance. Six CpG sites revealed reduced methylation associated with CCU-extent. Furthermore, CCU-extent was associated with lower scores in verbal learning. All six CpG sites mediated the effects between CCU-extent and verbal learning free recall. Our results indicate that CCU is associated with certain patterns in the methylome. Furthermore, CCU-extent associated impairments in memory function are mediated via differential methylation of the six CCU-associated CpG sits. Six identified CpG are located in genes previously described in the context of neurodegeneration, hippocampus-dependent learning and neurogenesis. However, these results have to be carefully interpreted due to a small sample size. Replication studies are warranted.

Social control theory focuses on why some people do not commit deviant behaviours, such as illicit drug use. It proposes that bonding to conventional society constrains deviant conduct. In the book Causes of Delinquency, Hirschi distinguished four elements of social bonds: attachment, commitment, involvement, and belief. This study draws upon data from the 2012 Canadian Alcohol and Drug Monitor Survey to examine the effect of social control theory, specifically the element of attachment, on controlling cannabis use. This study also uses the element of attachment to interpret gender and rural/non-rural area differences in cannabis use. Two hypotheses are offered: (1) females are less likely to use cannabis than males because females have greater attachment to others; (2) rural residents are less likely to use cannabis than non-rural residents because rural residents have greater attachment to others. The research methods in the study are cross-tabulation analysis and binary logistic regression. The statistical analysis results support both hypotheses: females have a significantly lower rate of cannabis use than males and rural residents have a significantly lower rate of cannabis use than non-rural residents. Having greater attachment to others may be associated with a decreased rate of cannabis use. Policy and further research recommendations are made.

We have read and analyzed the article entitled “Prevalence of marijuana use among university students in Bolivia, Colombia, Ecuador and Peru”. We propose some objective points which could enhance the internal validity of the study (i.e., we suggest to report participation proportions).

Predicting teenage drug use is key to understanding the etiology of substance abuse. However, classic predictive modeling procedures are prone to overfitting and fail to generalize to independent observations. To mitigate these concerns, cross-validated logistic regression with elastic-net regularization was used to predict cannabis use by age 16 from a large sample of fourteen year olds (N=1,319). High-dimensional data (p = 2,413) including parent and child psychometric data, child structural and functional MRI data, and genetic data (candidate single-nucleotide polymorphisms, "SNPs") collected at age 14 were used to predict the initiation of cannabis use (minimum six occasions) by age 16. Analyses were conducted separately for males and females to uncover sex-specific predictive profiles. The performance of the predictive models were assessed using the area under the receiver-operating characteristic curve ("ROC AUC"). Final models returned high predictive performance (generalization mean ROC AUCmales=.71, mean ROC AUCfemales=.81) and contained psychometric features common to both sexes. These common psychometric predictors included greater stressful life events, novelty-seeking personality traits of both the parent and child, and parental cannabis use. In contrast, males exhibited distinct functional neurobiological predictors related to a response- inhibition fMRI task, whereas females exhibited distinct neurobiological predictors related to a social processing fMRI task. Furthermore, the brain predictors exhibited sex- specific effects as the brain predictors of cannabis use for one sex failed to predict cannabis use for the opposite sex. These sex-specific brain predictors also exhibited drug- specific effects as they failed to predict binge-drinking by age 16 in an independent sample of youths. When collapsed across sex, a gene-specific analysis suggested that opioid receptor genetic variation also predicted cannabis use by age 16. Two SNPs on the gene coding for the primary mu-opioid receptor exhibited genetic risk effects, while one SNP on the gene coding for the primary delta-opioid receptor exhibited genetic protective effects. Taken together, these results demonstrate that adolescent cannabis use is reliably predicted in males and females from shared and unique biobehavioral features. These analyses also underscore the need for refined predictive modeling procedures as well as sex-specific inquiries into the etiology of substance abuse. The sex-specific risk-profiles uncovered from these analyses might inform potential etiological mechanisms contributing to substance abuse in adolescence as all predictors were measured prior to the onset of cannabis use.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

<p>The most robust neurocognitive effect of marijuana use is memory impairment. Memory deficits are also high among persons living with HIV/AIDS, and marijuana use among this population is disproportionately common. Yet research examining neurocognitive outcomes resulting from co-occurring marijuana and HIV is virtually non-existent. The primary aim of this case-controlled study was to identify patterns of neurocognitive impairment among HIV patients who used marijuana compared to HIV patients who did not use drugs by comparing the groups on domain T-scores. Participants included 32 current marijuana users and 37 non-drug users. A comprehensive battery assessed substance use and neurocognitive functioning. Among the full sample, marijuana users performed significantly worse on verbal memory tasks compared to non-drug users and significantly better on attention/working memory tasks. A secondary aim of this study was to test whether the effect of marijuana use on memory was moderated by HIV disease progression, but these models were not significant. This study also examined whether the effect of marijuana use was differentially affected by marijuana use characteristics, finding that earlier age of initiation was associated with worse memory performance. These findings have important clinical implications, particularly given increased legalization of this drug to manage HIV infection.</p> / Dissertation

Thesis deals with currently discussed topic -- the medical use of cannabis -- the missing possibility in the current medicine state in the Czech republic. Despite the fact that cannabis seems to be very effective for medical use, official medical use of cannabis permitted by law can be observed in only few countries. Czech republic doesn't belong among these countries, however there are some tendencies to change current situation. The goal of the thesis is to stand up for medical use of cannabis in the Czech republic and to contribute to above mentioned tendencies to change current situation. To reach the goal thesis introduces theoretical background of medical use of cannabis which explains advantages of its use, but primarily in the empirical part in which compares current (without the use of cannabis) and potential costs (with the use of cannabis) of the treatment of multiple sclerosis comes with the conclusion that with the use of cannabis is possible to save 1 931 923 444,- CZK.