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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.
71

The "e" in rave : a profile of young ecstasy users and its implication for educators

Zervogiannis, Fanitsa Helen 11 1900 (has links)
The use of methylenedioxymethamphetamine (MDMA) or Ecstasy is a phenomenon that has established itself in the widespread Rave culture. Ecstasy use causes not only physical, social and psychological problems in the development of the adolescent but may also influence his concentration and learning abilities. To prevent these problems educators should be well informed regarding current drug use trends and also be capable of assisting adolescents. Research regarding the nature of Ecstasy use and the characteristics of its users is lacking nationally. The increase in use amongst school going adolescents and young adults and the fact that there are side effects and unknown long term effects has made it imperative that educators learn as much as possible about this drug. The purpose of this research is therefore to furnish the educator with accurate information that will enable him to obtain a reference point from which assistance can be offered to the young Ecstasy user. / Psychology of Education / M.Ed.(Guidance and Counselling)
72

Interacció farmacològica entre la 3.4-Metilendioximetamfetamina (MDMA, Èxtasi) i la paroxetina en humans

Segura Agulló, Mireia 09 July 2004 (has links)
La 3,4-metilendioximetamfetamina (MDMA, èxtasi) és una droga de síntesi que es consumeix entre els joves de forma recreativa. S'ha postulat que la 3,4-dihidroximetamfetamina (HHMA), metabòlit que es forma a partir de l'O-demetilenació de la MDMA a través majoritàriament de l'isoenzim CYP2D6, podria tenir un paper important en el desenvolupament de la neurotoxicitat atribuïda a la MDMA. Així, un dels objectius de la tesi ha estat establir quin paper juga i quina importància té, des d'un punt de vista quantitatiu, aquest metabòlit HHMA en el metabolisme global de la MDMA in vivo. Per altra banda, el CYP2D6 és un enzim polimòrfic, i potencialment els subjectes metabolitzadors lents per aquesta acitivitat enzimàtica podrien tenir un risc més alt de patir toxicitat aguda. La MDMA es consumeix sovint concomitantment amb inhibidors selectius de la recaptació de serotonina (SSRI). Alguns SSRI, com la paroxetina i la fluoxetina, són inhibidors del CYP2D6 i es pot preveure una interacció metabòlica entre aquests tipus de substàncies. Mitjançant un assaig clínic (aleatori, doble cec, creuat i controlat amb placebo) en humans, s'ha estudiat la rellevància de la inhibició de l'activitat del CYP2D6, la seva contribució en el metabolisme de la MDMA i els efectes farmacològics que resulten de la co-administració de la MDMA i la paroxetina.Han estat determinades les concentracions plasmàtiques i urinàries de la MDMA i dels metabòlits més importants de la MDMA, així com les concentracions plasmàtiques de paroxetina juntament amb el seu metabòlit principal.Dels resultats obtinguts, la tesi conclou que l'HHMA és un metabòlit rellevant en la disposició metabòlica de la MDMA. L'estudi d'interacció mostra que la MDMA veu reduït el seu metabolisme oxidatiu al voltant d'un 30% i que ambdós compostos mostren una interacció metabòlica. El CYP2D6 podria contribuir in vivo en l'O-demetilenació de la MDMA en un 30%. / 3,4-methylenedioxymethamphetamine (MDMA) is a synthetic amphetamine derivative misused among youths for recreational purposes. It has been postulated that 3,4-dihydroxymethamphetamine (HHMA), a metabolite resulting from the O-demethylenation of MDMA through CYP2D6 may play a role in the development of the neurotoxicity. Thus, one of the major aims of the thesis was to establish HHMA relevance, from a quantitative point of view, in MDMA metabolism. Moreover, CYP2D6 is a polymorphic enzyme and the participation of CYP2D6 in the oxidative metabolism of MDMA may suggest an increased risk for acute toxicity in poor metabolizers for this enzymatic activity. MDMA is sometimes consumed concomitantly with selective serotonin reuptake inhibitors (SSRI). Some SSRI are potent CYP2D6 inhibitors such as paroxetine or fluoxetine and a metabolic interaction between these drugs and MDMA could be expected. Thus, interaction studies of MDMA with SSRI may be an in vivo approach to evaluate the contribution of CYP2D6 on MDMA disposition and the effects of the co-administration of both compounds. The major objective was to assess the contribution of CYP2D6 to MDMA disposition using paroxetine as a metabolic probe inhibitor. It was carried out a clinical trial in humans. The study was randomized, double blind, crossover, and controlled with placebo. Plasma concentration-time profiles and urinary recoveries of MDMA and main metabolites including HHMA were obtained. Paroxetine and its main metabolite (hydroxy-methoxy-paroxetine) plasma concentrations were also determined. From the results obtained, it is conclude that HHMA is a relevant metabolite on MDMA disposition in humans. The interaction study shows a 30% reduction of MDMA metabolic disposition and both MDMA and paroxetine show a pharmacodynamic interaction. It is estimated that CYP2D6 may accounts for a 30% of MDMA O-demethylenation in humans.
73

La Influència de l'estereroquímica en el metabolisme de la 3,4-metilendioximetamfetamina (MDMA, èxtasi)

Pizarro Lozano, Mª Nieves 15 October 2004 (has links)
La MDMA és cap de sèrie dels entactògens. El seu consum provoca toxicitat aguda i neurodegeneració a mig/llarg termini del sistema serotoninèrgic. Es postula que la bioactivació metabòlica podria ser responsable del desenvolupament de neurotoxicitat.La MDMA té un centre estereogènic. Es consumeix com a racemat, però els enantiòmers tenen perfils farmacològics diferenciats. A més, la MDMA té una depuració metabòlica enantioselectiva i autoinhibible (CYP2D6). Aquesta tesi presenta l'enantioselectivitat de la depuració metabòlica de la MDMA en consumidors recreatius participants d'un assaig clínic (dosi: 100 mg).Es sintetitzà material de referència i es desenvolupà metodologia per a l'anàlisi enantioselectiu i diastereoselectiu dels compostos.S'estudià l'enantioselectivitat en el metabolisme fins a 48h post-administració, obtenint-se raons (R)-MDMA/(S)-MDMA>1 i en augment amb el temps. Les raons del metabòlits majoritaris foren pràcticament constants i properes a 1, possiblement degut a la inhibició metabòlica del CYP2D6 i a la participació d'altres enzims no enantioselectius. / La MDMA es la cabeza de serie de los entactógenos. Su consumo provoca toxicidad aguda y neurodegeneración serotonérgica a medio/corto plazo. Se postula que una bioactivación metabólica podría ser responsable del desarrollo de neurotoxicidad.La MDMA tiene un centro estereogénico. Se consume como racemato, pero los enantiómeros tienen perfiles farmacológicos diferenciados. Además, presenta depuración metabólica enantioselectiva y autoinhibible (CYP2D6).Esta tesis presenta la enantioselectividad de la depuración metabólica de la MDMA en consumidores recreativos participantes de un ensayo clínico (dosis: 100 mg).Se sintetizó material de referencia y se desarrolló metodología para el análisis enantioselectivo y diastereoselectivo de los compuestos.Se estudió la enantioselectividad en el metabolismo hasta 48h post-administración, obteniéndose relaciones (R)-MDMA/(S)-MDMA>1 y en aumento con el tiempo. Las relaciones de los metabolitos mayoritarios fueron prácticamente constantes y cercanas a 1, posiblemente debido a la inhibición metabólica del CYP2D6 y a la participación de otros enzimas no enantioselectivos. / MDMA is the head of entactogenic compounds. Its consumption causes acute toxicity and mid/long term serotonergic neurodegeneration. It is postulated that a metabolic bioactivation may be responsible for development of neurotoxicity.MDMA has a stereogenic center. It is consumed as a racemate, but its enantiomers have different pharmacological profiles. Also, MDMA presents an enantioselective and self-inhibited metabolic disposition (CYP2D6).The present thesis shows data about enantioselective metabolic disposition of MDMA in recreative consumers that participated in a clinical trial (dose: 100 mg).It was synthesised reference material and it was developed methodology for both enantioselective and diastereoselective analysis MDMA and its main metabolites.It was studied the enantioselectivity in the metabolism after 48h post-administration. (R)-MDMA/(S)-MDMA ratios were >1 and increasing over time. Major metabolites ratios were practically constant and close to 1, possibly because of the metabolic inhibition of CYP2D6 and the role of other non-enantioselective enzymes.
74

Coping with Acculturative Stress: MDMA Usage among Asian American Young Adults in the Electronic Dance Music Scene

Chan, Michelle Stephanie 01 January 2017 (has links)
The intersection of Asian American identity and illicit substance use is greatly understudied in psychological literature, especially with matters of mental health and drug use being stigmatized by Asian cultural norms. However, with an increasingly alarming number of fatal drug overdoses by Asian Americans at electronic dance music (EDM) events, attention must be drawn to the needs of this unique population. The present study characterizes this community by drawing from data of 1,290 Asian American young adults who participate in the EDM scene. This study also hypothesizes the impact of acculturative stress and feelings of social belonging on MDMA usage patterns. Analysis reveals a population of largely East and Southeast Asian, 2nd generation, college-educated young adults with strikingly high usage rates of MDMA, an illicit drug linked to the EDM scene. Multiple regression models were created that could predict MDMA use through various measures related to acculturative stress and social belonging. Findings revealed the significant impact of acculturation, acculturative stress, mental health, peer relationships, and desires for social belonging on this population’s MDMA usage patterns, providing an important platform from which future research may launch much-needed additional studies of Asian American young adults and illicit drug use.
75

The Cytotoxic Mechanisms of Hepatotoxicity Induced by Methamphetamine and 3,4-Methylenedioxy-Methamphetamine Under Normothermic and Hyperthermic Conditions

Frommann, Nicole P. January 2020 (has links)
No description available.
76

Study of the interaction between 3,4 methylenedioximethamphetamine and the endocannabinoid system

Touriño Raposo, Clara 17 February 2009 (has links)
La 3,4-metilendioximetamfetamina (MDMA, èxtasi) i el cannabis són dues drogues les quals es consumeixen conjuntament de manera habitual. Malgrat que tots dos compostos presenten propietats reforçant i potencial addictiu, també tenen propietats farmacològiques oposades. La MDMA es una droga psicoestimulant, la qual causa hiperlocomoció, hipertèrmia, resposted de tipus asiogènic i neurotoxicitat. Per altra banda el Δ9-tetrahydrocannabinol (THC), principal compost psicoactiu del cannabis, posseeix efectes relaxants, hipolocomotors, hipotèrmics i neuroprotectors. Els efectes de la MDMA i el THC al sistema nerviós central es troben mediats per dos mecanismes notablement diferents. La MDMA augmenta els nivells extracel·lulars de dopamina i serotonina, mentre que el THC produeix l'activació del receptor cannabinoide CB1. Cal destacar a més que les interaccions entre els sistemes monoaminèrgic i endocannabinoide s'observa de manera freqüent en l'organisme.En el present estudi hem explorat la implicació del sistema endocannabinoide i la MDMA en diversos aspectes. Per una banda el receptor cannabinoide CB1 juga un important paper en els efectes hiperlocomotors i hipertèrmics, i en les respostes de tipus ansiogènic produïdes per la MDMA. Curiosament, encara que el receptor CB1 no participa en els efectes recompensants primaris de la MDMA, és imprescindible per que tinguin lloc els seus efectes reforçants. Així mateix, l'alliberació de serotonina per part de la MDMA redueix de manera dosi-depenent la simptomatologia física causada pel síndrome d'abstinència a cannabinoides precipitada per un antagonista del receptor CB1. Finalment, el tractament amb THC era capaç de prevenir la hipertèrmia, activació glial, estrès oxidatiu i pèrdua de terminals causada per la MDMA. Com a conseqüència el THC exerceix un efecte neuroprotector contra la neurotoxicitat induïda per la MDMA. / 3,4-methylenedioximethamphetamine (MDMA, ecstasy) and cannabis are two drugs frequently consumed in combination. Despite both compounds have rewarding properties and abuse liability, they show opposite pharmacological properties. On the one hand, MDMA is a psychostimulant drug with hyperlocomotor, hyperthermic, anxiogenic-like and neurotoxic effects. On the other hand, Δ9-tetrahydrocannabinol (THC), the main psychoactive compound of cannabis, has relaxant, hypolocomotor, hypothermic and neuroprotective properties. The effects of MDMA and THC in the central nervous system are mediated by two different mechanisms. MDMA enhances the extracellular levels of dopamine and serotonin, whereas THC activates the CB1 cannabinoid receptor. Likewise, interactions between the monoaminergic and the endogenous cannabinoid system have been frequently observed.In the current study, we explored the involvement of CB1 cannabinoid receptor on the hyperlocomotor, hyperthermic, anxiogenic-like, rewarding and reinforcing effects of MDMA. We also studied the effect of acute and chronic administration of MDMA on rimonabant-precipitated THC withdrawal syndrome. Furthermore, we explored the neuroprotective effects of THC on MDMA-induced neurotoxicity.As a result of this study we may conclude that endocannabinoid system and MDMA interact in a wide variety of aspects. CB1 receptor plays an important role on the hyperlocomotor, hyperthermic, and anxiogenic-like effects of MDMA. Interestingly, CB1 receptor is essential for the reinforcing but not the primary rewarding properties of MDMA. In addition, the release of serotonin by MDMA dose-dependently reduced the severity of THC withdrawal syndrome triggered by a CB1 antagonist. Finally, pretreatment with THC prevented the hyperthermia, glial activation, oxidative stress and terminal loss caused by MDMA. Consequently, THC exerts a neuroprotective effect against MDMA-induced neurotoxicity.

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