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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Efeitos do uso de Cannabis sativa sobre o desenvolvimento do baço e timo em prole de camundongos (BalbC) durante a gestação / Effects of Cannabis sativa on the development of spleen and thymus in offspring mice (BalbC) during pregnancy

Daiana Aparecida Souza Lima 11 September 2018 (has links)
Cannabis sativa (maconha) é a droga ilícita mais conhecida e utilizada em todo o mundo. Recentemente, o uso recreativo da droga por jovens aumentou muito, especialmente entre as gestantes. Estudos indicam que seu uso na gestação causa efeitos fetotóxicos adversos, no entanto, poucos estudos avaliam esses efeitos durante este período crítico sobre o desenvolvimento do sistema imunológico. Neste estudo, avaliamos o impacto da exposição gestacional à fumaça de maconha resultante da queima de cigarros sobre o desenvolvimento do baço e do timo de proles de camundongos BalbC. Utilizamos um modelo que se aproxima das reais condições de uso humano (inalação) sob os aspectos de dose e média exposição. Camundongos fêmeas gestantes (n = 20) foram expostas ao fumo da maconha ou ao ar filtrado (grupo controle) do 5,5° ao 17,5° dia gestacional (DG) por 5 minutos diariamente. Para isso, foi utilizado um aparelho para inalação da fumaça desenvolvido em nosso laboratório, onde os cigarros de maconha (200mg de Cannabis sativa) foram queimados e a fumaça conduzida para a câmara de exposição dos animais (exposição somente inalatória). Os baços e timos das proles foram coletados no 18,5° dia gestacional (DG), 20° e 60° dias pós-natais (DPN) para a realização das análises histológica e histoquímica. Avaliações morfológicas e quantitativas dos órgãos foram realizadas utilizando-se métodos estereológicos e por meio da semi quantificação de fibras do sistema colágeno. Os resultados indicam um aumento no peso corporal dos animais com 60 DPN cujas mães foram expostas ao fumo de Cannabis sativa durante a gravidez. Os machos com 60 DPN expostos apresentaram redução no volume total do timo, assim como em seus principais compartimentos, medula e córtex, onde também foi observado um aumento de fibras do sistema colágeno, quando comparados aos animais controles. Além disso, o baço desses animais também apresentou redução significativa em seu volume, porém não houve redução significativa no volume total da polpa vermelha. Machos e fêmeas com 60 DPN do grupo exposto apresentaram redução no volume total da polpa branca e aumento de fibras do sistema colágeno na região das trabéculas do parênquima do baço. Em suma, a exposição gestacional à maconha causa efeitos fetotóxicos que podem ser observados por alteração no baço e no timo da prole (sendo os efeitos distintos para machos e fêmeas) e estas alterações se tornam mais marcantes com o avanço da idade do animal, com potencial comprometimento da resposta imune nesses indivíduos. / Cannabis sativa (marijuana) is one of the most well-known and used illicit drugs worldwide. Recently, recreational use of that drug among young people has increased greatly, especially among pregnant women. Studies indicate that its use in pregnancy causes adverse fetotoxic effects, however there are few studies evaluating the effects of marijuana use during this critical period on the developing immune system. In this study, we evaluated the impact of gestational exposure to smoke marijuana resulting from burning cigarettes on the spleen and thymus development of BalbC mice offspring. We have used a model that approximates the real conditions of human use (inhalation) under the dose and medium exposure aspects. Pregnant mice (n=20), were exposed to marijuana smoke or filtered air (control group) from 5.5° to 17.5° gestational day (GD) for 5 minutes daily. Thus, we used a smoke inhalation apparatus developed in our laboratory where the marijuana cigarettes (200mg of Cannabis sativa) were burned and conducted to exposure chamber reaching the animals (nose-only exposure). Spleen and thymus of the offspring were collected on the 18.5° gestational day (GD), 20° and 60° postnatal day (PND) for the histological and histochemical analysis. Morphological and quantitative evaluations of these organs were performed using stereological methods and semi quantification of collagen fibers. The results indicate an increase in the mice body weight at PND 60 whose mothers were exposed to Cannabis sativa smoke during pregnancy. The PND 60 males from exposed group showed lower thymus total volume, as well as its main compartments such as medulla and cortex, where collagen fibers was also observed, when compared with males from the control group. Also, the spleen of these animals also presented a significant reduction, however no significant reduction was showed in the total volume of the red pulp. In addition, males and females from the exposed group at PND 60 presented reduction in total volume in the white pulp and increased of collagen fibers in the trabeculae region of the spleen. In summary, gestational exposure to marijuana causes fetotoxic effects that can be observed due to alteration in the spleen and thymus of the offspring (the effects being different for males and females), and these changes being marked with the advancement of the age, with potential impairment of the immune response in these individuals.
142

Caracterização química da planta Cannabis sativa L. a partir de sementes apreendidas pela Polícia Federal no Estado do Rio Grande do Sul

Borille, Bruna Tassi January 2016 (has links)
A Cannabis sativa L. (canábis) contém centenas de substâncias químicas em diferentes classes, contudo, a classe dos canabinoides é encontrada unicamente nesta espécie. Popularmente conhecida como maconha, a canábis é a droga ilícita mais consumida no mundo, sendo o Δ9-tetrahidrocanabinol (Δ9-THC), o principal canabinoide de interesse toxicológico, por ser o responsável pela maioria dos efeitos psicotomiméticos ocasionados e estar associado ao uso abusivo da planta. De outro modo, há alguns anos, vem crescendo significativamente o interesse em pesquisas científicas com a canábis, devido aos importantes efeitos terapêuticos que alguns canabinoides têm apresentado. O canabidiol (CBD), por exemplo, é um canabinoide que além de modular os efeitos eufóricos do Δ9-THC, tem apresentado importantes atividades farmacológicas. Embora haja um crescente aumento nas toneladas de apreensões de canábis realizadas no Brasil, não existem dados que caracterizem o perfil químico e a potência da droga que é utilizada ilegalmente no país. Outro aspecto singular com relação às apreensões de canábis refere-se à nova forma de tráfico internacional de drogas, que vem crescendo significativamente no país. Trata-se da remessa de sementes de canábis em pequenas quantidades através de empresas de transporte. Desta forma, este estudo foi realizado a partir de sementes de canábis apreendidas pela Superintendência de Polícia Federal no Rio Grande do Sul. As sementes foram germinadas e as plântulas foram cultivadas, secas e analizadas, sendo todos os passos em condições controladas. As metodologias analíticas utilizadas foram: espectroscopia no infravermelho próximo (NIRS), espectrometria de massas por ressonância ciclotrônica de íons com transformada de Fourier (FT-ICR MS) e cromatografia à gás com detector de massas (CG/EM). O elevado número de compostos presente nas plantas torna os dados obtidos muito complexos, onde pequenas diferenças entre amostras podem ser negligenciadas. Por isso, foram utilizadas as seguintes ferramentas quimiométricas: HCA, PCA, PLS-DA e SVM-DA. As diferentes metodologias de análise utilizadas neste trabalho, permitiram a análise de um total de 73 amostras de canábis que forneceram dados sob químicos, bem como aspectos distintos e relevantes em toxicologia. As informações obtidas por NIRS associadas às ferramentas quimiométricas HCA e PCA possibilitaram agrupar 29 amostras de canábis em diferentes períodos de crescimento; e as ferramentas quimiométricas PLS-DA e SVM-DA permitiram classificar 29 amostras de canábis em diferentes períodos de crescimento com 100% de acerto. O altíssimo poder de resolução da FT-ICR MS possibilitou a identificação 123 compostos canabinoides e metabólitos a partir das análises realizadas em 73 amostras de canábis, o que resultou na compilação de um abrangente perfil químico de canabinoides, até então não obtido. A eficiência de separação da CG acoplada à identificação dos compostos utilizando EM tornou possível a diferenciação de 73 amostras de canábis em tipo fibra ou tipo droga, além da caracterização do perfil químico de canabinoides e terpenoides presentes nas amostras, obtido pela análise em CG/EM. Desta forma, os dados gerados com o desenvolvimento desta tese possibilitaram a identificação e o conhecimento do perfil químico de amostras de canábis apreendidas no Brasil, apresentando informações até então desconhecidas pela polícia brasileira, bem como pelos profissionais da saúde, comunidade científica, órgãos governamentais e políticos do país e também para a população em geral. / Cannabis sativa L. (cannabis) contains hundreds of different classes of chemicals, however, the class of cannabinoids is found only in this plant. Popularly known marijuana, cannabis is the most used illicit drug worldwide, and the Δ9-tetrahydrocannabinol (Δ9-THC), the main cannabinoid regarding toxicological interest, being responsible by the majority of psychotomimetic effects and it is associated with the abuse of the plant. Otherwise, for a few years has grown significantly the interest and scientific research with cannabis due to significant therapeutic effects that certain cannabinoids have shown. The cannabidiol (CBD), for example, is a cannabinoid which in addition to modulate the euphoric effects of Δ9-THC, it has shown significant pharmacological activity. Although there is a growing increase in tons of cannabis seizures conducted in Brazil, there are no data which characterize the chemical profile and potency of the drug that is illegally used in the country. Another unique aspect regarding cannabis seizures refers to the new form of international drug trafficking that has grown significantly in the country. This is the shipment of cannabis seeds in small quantities by transportation companies. Thus, this study was based on samples from cannabis seeds seized by the Superintendence of the Federal Police in Rio Grande do Sul. The seeds were germinated and the seedlings were grown, dried and analyzed, all of the steps under controlled conditions. The analytical methods used were: near infrared spectroscopy (NIRS), Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) and gas chromatography coupled with mass spectrometry (GC/MS). The high number of compounds presente in plants renders them very complex data set, where small differences between samples may be wasted. Therefore, the following chemometric tools were used: HCA, PCA, PLS-DA and DA-SVM. The different methods of analysis used in this study allowed the analysis of a total of 73 samples of cannabis that provided data on chemical and distinct and relevant aspects in toxicology. Information obtained by NIRS chemometric tools associated with HCA and PCA group allowed 29 samples of cannabis in different periods of growth; and chemometric tools PLS-DA and SVM-DA can be classified 29 samples of cannabis in different periods of growth with 100% accuracy. The very high resolution power of FT-ICR MS possible to identify 123 compounds cannabinoids and metabolites from the analyzes carried out on 73 samples of cannabis, which resulted in the compilation of a comprehensive chemical profile of cannabinoids, has not been surpassed. The GC separation efficiency coupled with the identification of compounds using MS made it possible to differentiate 73 cannabis samples in type or fiber type drug, besides the characterization of the chemical profile of cannabinoids and terpenoids present in the samples obtained through the analysis on GC/MS. Thus, the data generated with the development of this thesis allowed the identification and knowledge of the chemical profile of cannabis samples seized in Brazil, presenting information previously unknown to Brazilian police as well as by health professionals, the scientific community, government agencies and politicians of the country and also to the general population.
143

Inégalités de genre et inégalités sociales dans les usages de drogues en France / Gender inequalities and social inequalities in drug use in France

Legleye, Stéphane 17 November 2011 (has links)
Les usages de produits psychoactifs contribuent fortement aux inégalités sociales de santé et sont aussi inégalement distribués suivant le sexe. En utilisant des enquêtes en population générale et adolescente, ce travail montre que les écarts de consommations d’alcool, de tabac, de cannabis et d’autres drogues illicites entre hommes et femmes varient suivant le milieu social, la génération de naissance, le statut scolaire et professionnel et les conditions de travail. Parmi les adolescents, les écarts de consommations entre garçons et filles dépendent moins du milieu social qu’à l’âge adulte, mais les risques d’expérimenter puis de progresser vers des usages fréquents ou problématiques en dépendent au contraire fortement. Ces résultats montrent que les différences d’usages entre hommes et femmes sont des différences de genre, socialement construites et en lien avec le système des inégalités sociales ; ils présentent également quelques déterminants des trajectoires d’usages de drogues. / Licit and illicit drug consumptions are strong contributors to the social inequalities in health, but they are also unevenly distributed among men and women. Using general population and adolescent surveys, this work shows that the differences between men and women in alcohol, tobacco, cannabis and other illicit drugs vary according to the social position, age and birth cohort, occupational and school status as well as according to working conditions. Among adolescents, the variation of the differences between boys and girls with the family socio-economic status are rather low, but the affluence of the family is a key factor for experimenting alcohol and drugs whereas it lowers the risk of transition to frequent and problematic drug use. These results show that the differences in drug use between men and women are gender differences, socially constructed and linked with the system of social inequalities; they also point out some key determinants of the drug use trajectories.
144

Associação do uso recreacional da maconha durante a gestação com desfechos gestacionais e comportamentais em camundongos / Association of the recreational use of marijuana during pregnancy with gestational outcomes and behavior in mice

Benevenuto, Sarah Gomes de Menezes 20 July 2016 (has links)
A maconha é a droga ilícita mais consumida entre gestantes. Entretanto, os efeitos do uso materno sobre a gestação e o desenvolvimento fetal não são bem esclarecidos. Estudos experimentais e epidemiológicos apresentam resultados conflitantes devido à via de administração, tempo de exposição, dose e como a toxicidade da Cannabis é testada. Neste estudo experimental foram investigados os efeitos da inalação materna da fumaça de Cannabis sativa, aproximando as reais condições de uso da droga por humanos. Camundongas gávidas (n=20) foram expostas diariamente durante 5 minutos à fumaça decorrente da queima de maconha ( 0,2 g de Cannabis), ou ao ar filtrado, a partir do 5,5° dia gestacional (DG) ao 17,5° DG. A ingestão de alimentos e o peso materno foram registrados. Análise por ultrassom foram realizadas entre o 10,5° e o 16,5° DG. No 18,5° DG metade das fêmeas foram eutanasiadas para a a avaliação dos fetos a termo, reabsorções e placentas. A duração da gestação, desfechos neonatais e comportamentais (reflexo, força muscular, ansiedade e memória) em neonatos e adultos foram avaliados na outra metade das fêmeas. A exposição diária de 5 min (dose baixa) durante a gestação resultou em redução do peso ao nascer mas o tamanho da prole não foi alterado; No entanto, o número de filhotes machos por prole foi maior. Além disso, o peso líquido da placenta foi aumentado e a proporção feto/placenta foi diminuída em machos, mostrando um efeito específico do sexo. A exposição também alterou a força muscular e reflexos em neonatos, além de causar prejuízos na memória e efeito ansiolítico na prole exposta. Em conclusão, os resultados indicam que o fumo da maconha durante a gestação, mesmo em doses baixas, pode ser embriotóxico, fetotóxico e pode alterar o comportamento em neonatos e adultos / Marijuana is the most used illegal drug among pregnant women. However, the effects of maternal use on pregnacy and fetal development are not well understood. Experimental and epidemiologicals studies have show conflicting results due to the route of administration, duration of exposure, dose, and a toxicity of Cannabis is tested. In this experimental study we investigated the effects of maternal inhalation of smoke Cannbis sativa , approaching the actual drug use conditons for humans. Pregnant mice (n=20) were exposed (only noise) daily for 5 min to smoke resulting from burning marijuana (0.2g Cannabis), or filtered air, from gestational day (GD) 5.5° to GD 17.5°. Food intake and maternal weight were recorded. Ultrasound analysis was performed on 10.5 and 16.5° GD. On 18.5° GD half the mice were euthanized for evaluation of term fetus, resorptions and placenta. The duration of pregnancy , neonatal outcomes and behavioral reponses (reflex,muscle strenght, anxiety and memory) were assessed in the other half of the females. The daily exposure of 5 min (low dose) during pregnancy resulted in reduced brth weiht but the size of the offspring was not changed; however, the number of males per offspring pups was higher. In addition, placental weight was increased and fetus/placenta ratio was decreased in males, showing a particular effect of sex.The exposure also altered muscle strength and reflexes in newborns and cause impars in memory and anxiolytic effects in exposed offspring. In conclusion, the results indicate that smoking marijuana during pregnancy, even in low doses, can be embryotoxic, foetotoxic and may change in the behavior in neonates and adults
145

Do they get high? The effects of Amsterdam\'s coffeeshops on Air Bnb renting prices / Preços chapados ?os efeitos de coffeshops em alugués de Air Bnb em Amsterdam

Castro, Igor Gonçalves Koehne de 26 September 2018 (has links)
The drug issue has a massive impact on almost every society nowadays. It has deep influences in people\'s quotidian and an almost ubiquitous growth in consumption. This study aims at assessing whether the textitde facto legal sale of cannabis influences real estate prices. Evaluating how these prices change gives us some notion of the externalities involved in those sales and how people regard it. We organized a panel with georeferenced data from Air Bnb lodgings offered in Amsterdam, from May 2014 until July 2017. During this period, several coffeeshops were closed due to new legislation. We estimate that losing the closest coffeeshop, when it is within a 250m radius from the lodging, decreases the renting price, on average, on 3%, and when it is farther has no significant impact. / A questão das drogas hoje em dia possui impacto massivo em praticamente todas as sociedades. Ela possui influências profundas no cotidiano das pessoas e um ubíquo crescimento no consumo. Esse estudo visa investigar se a venda legal de maconha influencia preços de imóveis. Avaliando como esses preços mudam nos dá uma noção tanto das externalidades envolvidas no processo de venda, quanto de como as pessoas se sentem com relação a elas. Organizamos um painel com dados georeferenciados de apartamentos do Air Bnb ofertados em Amsterdam, de Maio de 2014 à Julho de 2017. Durante esse período, diversos coffeeshops foram fechados devido a nova legislação local. Nós estimamos que este fechamento, quando ocorrido a menos de 250m de um apartamento, diminui o preço do aluguel, em média, em quase 3%, e não possui influências significantes para maiores distâncias.
146

The Cannabis Use Problems Identification Test (CUPIT) : development and psychometrics : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Psychology at Massey University, Palmerston North, New Zealand

Bashford, Janet Lorraine January 2007 (has links)
Lack of a brief empirically-verified screener for problematic and potentially problematic cannabis use has hampered implementation of a proactive opportunistic cannabis screening and early intervention (SEI) initiative in New Zealand. Addressing this instrumentation need was the primary aim of this thesis. This thesis also investigated the nature, prevalence, severity, and natural history of cannabis-related problems among a heterogeneous sample of 212 ‘at risk’ adolescent and adult users recruited from the community. In a 3-phase developmental design the CUPIT question candidates were first generated employing an Expert Panels methodology. The CUPIT structure, crosssectional, and longitudinal psychometric properties were then systematically tested, incorporating measures of cannabis-related pathology and DSM-IV/ICD-10 diagnoses of cannabis use disorders as criterion standard. High levels of cannabis consumption and related health and psychosocial problems reported portrayed a highly-disordered sample, most marked among adolescents. DSMIV/ICD-10 diagnoses were almost universal with no significant adolescent/adult differences in dependence symptoms count or severity. The two CUPIT subscales (Impaired Control, Problems) derived from principal components analyses exhibited good test-retest and internal consistency reliability and highly significant ability to discriminate diagnostic subgroups along the severity continuum (nonproblematic, risky, problematic use). At the 12-month follow-up, 194 adolescents and adults reported significantly increased cannabis consumption (adolescents), symptoms, and dependence severity. Baseline CUPIT subscale scores demonstrated highly significant longitudinal predictive utility for respondents’ diagnostic group membership, health and psychosocial problems, and significantly improved prediction of other measured outcomes in conjunction with age and gender. ROC analyses identified a CUPIT score of 12 to be the optimal cut-point for maximum sensitivity for both currently diagnosable cannabis use disorder and those ‘at risk’ in this sample. The empirical findings of this thesis research provide a compelling rationale for systematic implementation of opportunistic SEI among consumers of publicly-funded health and social services in New Zealand. Data confirmed that the vast majority of those needing help are unaware, or do not perceive, they need help. This thesis argues that, facilitated by the CUPIT, reliable proactive detection and appropriate intervention for early-stage cannabis use problems has potential for enormous cumulative impact on public health gains and the individual’s quality of life.
147

Pathways into ecstasy use: The role of prior cannabis use and ecstasy availability

Zimmermann, Petra, Wittchen, Hans-Ulrich, Waszak, Florian, Nocon, Agnes, Höfler, Michael, Lieb, Roselind 10 April 2013 (has links) (PDF)
Aim: To explore the role of cannabis use for the availability of ecstasy as a potential pathway to subsequent first ecstasy use. Methods: Baseline and 4-year follow-up data from a prospective-longitudinal community study of originally 3021 adolescents and young adults aged 14–24 years at baseline were assessed using the standardized M-CIDI and DSM-IV criteria. Results: Baseline cannabis users reported at follow-up more frequent access to ecstasy than cannabis non-users. Higher cannabis use frequencies were associated with increased ecstasy availability reports. Logistic regression analyses revealed that cannabis use and availability of ecstasy at baseline are predictors for incident ecstasy use during the follow-up period. Testing simultaneously the impact of prior cannabis use and ecstasy availability including potential confounders, the association with cannabis use and later ecstasy use was confirmed (OR = 6.3; 95% CI = 3.6–10.9). However, the association with ecstasy availability was no longer significant (OR = 1.2; 95% CI = 0.3–3.9). Conclusions: Results suggest that cannabis use is a powerful risk factor for subsequent first onset of ecstasy use and this relation cannot be sufficiently explained by availability of ecstasy in the observation period.
148

Gröna utsikter : En analys av hampas (Cannabis sativa L.) förutsättningar som energigröda i Sverige

Johansson, Martin, Martell, Philip January 2015 (has links)
Hemp is a versatile plant with many uses that has been around for thousands of years. The plant is highly adaptable andwill cultivate in almost any soil. It has excellent remediation properties and has shown to be relatively consistent when itcomes to crop yields. The aim of this literature survey is to examine how hemp can be used to be considered asustainable energy crop in Sweden through database searches and interviews. Hemps characteristics as an energy cropand its remediation properties is evaluated and compared with other plants that are used in Sweden. The result showsthat hemp is a competitive crop when used for solid fuel and that a closed-loop solution is achievable. Further studiesare needed for a closed-loop solution to be possible when using hemp as a biogas crop, mainly for establishing asustainable waste treatment.
149

Non-replication of interaction between cannabis use and trauma in predicting psychosis

Kuepper, Rebecca, Henquet, Cécile, Lieb, Roselind, Wittchen, Hans-Ulrich, van Os, Jim 26 November 2013 (has links) (PDF)
Cannabis use is considered a component cause of psychotic disorder interacting with genetic and environmental risk factors in increasing psychosis risk (Henquet et al., 2008). Recently, two cross-sectional and one prospective study provided evidence that cannabis use interacts additively with trauma to increase psychosis risk (Houston et al., 2008, Harley et al., 2010 and Konings et al., 2011). In an attempt at further replication, we examined prospective data from the German Early Developmental Stages of Psychopathology (EDSP) study (Wittchen et al., 1998b and Lieb et al., 2000).
150

Det problematiska bruket : En diskurspsykologisk analys av fyra cannabisbrukares resonemang

Borgström, Jonas January 2012 (has links)
This study examines negative issues that cannabis users have experienced associated with cannabis use. The author made qualitative interviewsto unveil four cannabis users’ life stories. These stories were analyzed through the discourse psychologicalperspective interpretive repertoirein order to explore and identify analogies among the users. The author found that the respondents, despite their seemingly diverse backgrounds and personalities, carry a collective repertoire of similar experience and reasoning around cannabis and society which can be defined as a cannabis discourse; a discourse grounded in facts as well as speculations, arguments which separately may seem reasonable but altogether often appear contradictory, and real-life anecdotes that sometimes reflect paradoxical conclusions. It's suggested that the respondents, through their repertoire, construct and maintain this discourse while social stigma and legal retaliation strengthens it. These findings may be useful for social workers in order to understand cannabis users’ situation, societal vulnerability and sometimes controversial values, including the origins of such.

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