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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.
1

Behavioral Deficits and Associated Alterations in the Proteome in the Amygdala of Adolescent Rats Exposed to Delta9-Tetrahydrocannabinol as Juveniles

Mohammed, Afzaal Nadeem 14 December 2018 (has links)
Delta9-tetrahydrocannabinol (THC) is an active component of marijuana. During recent years, the popularity of marijuana in the United States has increased tremendously. Marijuana edibles are a form of marijuana that has become very popular in recent years. These are easily accessible not only to adolescents but also to young children. According to recent statistical data, the consumption of marijuana edibles by children below the age of 5 has increased 600% in the states that have legalized marijuana. This has led to an adverse impact on children’s health as evidenced by a sudden increase in the number of children seeking emergency assistance in hospitals. In the current research, we addressed the issue of possible persistent effects on children’s behavior due to an earlier exposure to THC. Juvenile rats were treated with 10 mg/kg of THC from postnatal day 10 through 16. Once they reached adolescence, these rats were tested using several behavioral paradigms. To evaluate the biological basis for the behavioral deficits observed, brain samples obtained from these rats were subjected to proteomic analysis to determine any altered pathways related to the behavior. Our behavioral data indicated that juvenile exposure to THC has no effect on anxiety-related behavior in adolescents. However, we observed a significant effect of treatment on multiple parameters related to social interactions. Of these, episodes and time of social play were significantly increased in the THC treated rats suggesting alterations in the reward circuit function occurring as a result of developmental THC exposure. In the proteomics, we observed a significant effect on relevant canonical pathways such as the changes in thrombin and opioid signaling. Thrombin signaling in neurons is associated with processes involved in the connection between neurons and opioid signaling is involved in the activation processes of the reward circuit suggesting that juvenile THC exposure alters these processes in adolescence which could have detrimental effects on behavior. Overall, our data suggest that consumption of edibles by juveniles leads to altered behavioral and biochemical outcomes in adolescence. This may be detrimental in terms of the appropriate acquisition of skills necessary for meeting the challenges in future life.
2

Výběr chemotypů konopí vhodných pro léčebné použití s převládající účinnou látkou THC / Selection of cannabis chemotypes suitable for therapeutic use with predominant active substance THC

Michnová, Lenka January 2016 (has links)
During recent years the possible medical application of cannabis has been discussed more and more. It turns out, that the active substances (cannabinoids cannabidiol and tetrahydrocannabinol) have a significant potential in medicine and do not have to be only misused as a recreational drug. The Department of Crop Production (Faculty of Agrobiology, Food and Natural Resources) is the first institution with granted permission to legally cultivate cannabis, with higher THC content than 0,3 %, for research purposes. The first part of literate review recapitulates the basic knowledge about the cannabis, its biologically active substances and current legislation. The second part describes the endocannabinoid system and utilization of cannabis in the field of medicine. This thesis aims to evaluate the THC and CBD content in seven different cannabis cultivar strains (Nurse Jackie, Conspiracy Kush, Jillybean, Jack Cleaner 2, Jack Skellington, Nordle and National Health Service). The cannabis plants were cultivated in three cultivation cycles. The content of active substances in dried and homogenised inflorescence was analysed by gas chromatography with flame ionization detection (GC-FID) according to UN methodology. Based on the analysis, the appropriate genotypes were chosen, which are in accordance of Regulation 236/2015 Sb. and needs of the patients. According to results it was found, that all seven analysed cultivars are suitable for medical utilization regarding the content of THC and CBD. The highest average content of THC was measured by cultivar Jack Cleaner 2. On the other hand, the lowest THC content was established by cultivar Nordle. It was demonstrated, that the differences in THC content are connected rather to genotype variation than cultivation factors. The main goal of the thesis was to discover which of the seven cultivars will be stable regarding not only THC and CBD content, but also the crop yield. In those regards the research shows the cultivar Jack Cleaner 2 and Nurse Jackie as the most suitable. Preliminary results indicate that these two cultivar strains would be the most suitable for the therapeutic purposes.
3

Exploring the relationship between cannabis and panic

Ward, David John Deen January 2010 (has links)
1.1 Background: Despite Cannabis being the most widely used recreational drug in the western world (Earlywine, 2002) little is known about its potential association with anxiety and panic pathology. 1.2 Literature Review: A systematic literature review was conducted with twenty-nine studies critically reviewed. Papers suggested contradictory and equivocal results across all research designs and anxiety disorders. Whilst a significant number of studies have observed an association between cannabis and anxiety/anxiety disorders, the nature and direction of that association is still a point of contention. 1.3 Research Report: No known British empirical research has focused on exploring relationships between cannabis and panic attacks. Also no known research has investigated the differential effects of consuming different types of cannabis on panic pathology. Inspired somewhat on established research (e.g. Zolvensky et al., 2006a) a cross-sectional study was undertaken to explore the potential relationship between cannabis and anxiety. A self-selecting opportunity sample of 306 students drawn from both of Leicester’s universities completed a battery of questionnaires concerning cannabis use, tobacco use, panic attack history, alcohol use, poly-substance use and various psychometrics. Significant levels of both cannabis use and panic attack history were reported among the sample. Survival analysis revealed cannabis users were of significant increased risk (OR 2.01) of experiencing a panic attack compared to non-users. Mann-Whitney analysis found cannabis users who use mainly high potency ‘sensimillia’ experienced significantly more lifetime panic attacks than those who used other types. Limitations are explored. 1.4 Implications: The research report concludes that cannabis use is a risk factor in experiencing panic attacks and experiencing more lifetime attacks. High potency cannabis further increases this risk. Education for substance misuse and mental health professionals is recommended along with cannabis use forming part of assessment for panic attacks/disorder. 1.5 Critical Appraisal: Reflective appraisal of the research process is presented alongside key learning points.
4

Population pharmacokinetics of ethanol and delta-9 tetrahydrocannabinol in human subjects

Jiang, Yu 01 August 2017 (has links)
The pharmacokinetics of ethanol and (-)-trans-isomer of 9-tetrahydrocannabinol (THC), and the pharmacokinetic interaction between them were characterized using statistical models in this thesis. In chapter II, a semi-mechanistic absorption rate dependent hepatic extraction model was developed to characterize ethanol pharmacokinetics. The statistical analysis conducted based on this model indicated no association between ethanol disposition and subject age or sex, and a 23% higher typical Vmax value, a 12.5% lower typical Km value for heavy drinkers compared with moderate drinkers. In chapter III, a parent-metabolite pharmacokinetic model was developed to simultaneously describe the concentration time profile of THC and its active metabolite 11-OH-THC. A parent-metabolite model with 3-compartment pharmacokinetic model for THC and a 2-compartment model for 11-OH-THC was found to best describe the pharmacokinetics of THC and 11-OH-THC simultaneously. In chapter IV, the pharmacokinetic interactions of ethanol on THC, 11-OH-THC and 11-nor-COOH-THC were evaluated using linear mixed effects models. The results suggested that co-administration of ethanol caused an increase in THC and 11-OH-THC systemic exposure, failed to influence the terminal elimination processes of THC and 11-OH-THC, and did not affect the pharmacokinetics of 11-nor-9-COOH-THC.
5

Action of CB1 and CB2 antagonists/inverse agonists on mantle cell lymphoma

Chui, Daniel January 2011 (has links)
In this study, the effects of antagonists to the cannabinoid receptors in MCL cell lines were studied. Results presented in this study show that signalling through cannabinoid receptor with antagonists such as SR141716, SR144528 decreases cell viability but hemopressin when analyzing with XTT. The decrease in cell viability by SR141716 is caused by apoptosis triggered after 5 hours of treatment. The CB1 expression was confirmed in all MCL cell lines tested via western blotting but the expression of CB2 and GPR55 – another receptor to which SR141716 has affinity - was not confirmed due to lack of reliable antibodies. Specific agonist to GPR55 – LPI (l-α-lysophosphatidylinositol) showed different response compared to SR141716 which suggests that the effect seen by SR141716 was not induced through GPR55. The effect induced by CB1/CB2 agonist AEA is shown to be neither through CB1 or CB2 alone but possibly on another receptor yet to be described.
6

EFFECTS OF ACUTE THC ADMINISTRATION ON EXTINCTION OF CONDITIONED FEAR RESPONSES IN HUMANS

Diggs, Herman Augustus 01 December 2010 (has links)
Skin conductance responses were used to assess the effects of THC on conditioned fear response amplitude and extinction using a fear conditioning and extinction paradigm that paired an aversive unconditioned stimulus (shock) with a conditioned stimulus (angry face). Participants (N = 10 males) exhibited conditioning to the CS+, as indicated by a larger CR to the CS+ than to the CS-. THC did not have a significant effect on extinction of the CR across trials, but there was a significant interaction of social anxiety with drug that suggests that THC may facilitate extinction of CR to fear-conditioned stimuli in more socially anxious individuals. These results provide support for the hypothesis that THC may act as an anxiolytic in fear-eliciting situations. The current study was limited by a small sample size and a potential confound that may have influenced the SCL during conditioned responding.
7

Vliv externích faktorů na produkci vybraných sekundárních metabolitů u konopí

Palíšek, Ondřej January 2017 (has links)
Presented diploma thesis is focused on production of secondary metabolites under influence of external factors.in cannabis (Cannabis sativa L.). Theoretival part contains phylogenetical, morphological and botanical characterization of the given species. The part is further expanded by description of major cannabis constituents and their biosynthetic pathways. In the end of the chapter, methods for elicitation are described. Main goal of the experimental part was to compare influence of vaious fertilizers and product containing coloid silver on morphological characteristics and selected secondary metabolites content. Highest yield was observed within plants fertilized by Powder Feeding. Highest THC content was observed in plants fertilized by Jungle in da Box. Variation of height, yield and secondary metabolites within experimental population was observed, however was not statistically conclusive. Influence of Altron Silver was not statistically proven.
8

Vliv skladování na změny obsahových látek konopí

Vomáčka, Vít January 2017 (has links)
This thesis deals with the effect of storage of cannabis on the level of content of its active substances. The theoretical portion focuses on a botanical characteristics sum-mary. It further describes the growing needs and options of cannabis on the fields and of medical cannabis in covered areas. Portion of the thesis deals with the use of each individual parts of the cannabis plant. The thesis contains detailed description of canna-binoids and other substances. It further describes the effect of individual external factors on the stability of cannabinoids in cannabis products. The last part of the theore-tical section deals with the ability to analyze cannabinoids. The goal of the experimental section was to discover effects of different type of storage on the level of content of cannabidiol and delta-9-tetrahydrocannabinol in cannabis samples. The setting included a gas chromatograph GC Fisons instruments with FID detector. These samples were regularly collected and ex-tracted during the period of one year. Retention periods of individual cannabinoids and calibration curves were created. The results showed a reduction of cannabinoids in higher temperatures. The results further confirmed storage of vacuumed materials at -20 °C temperature as the most appropriate type of storage for female inflorescence of can-nabis.
9

Prevalence of alcohol and drugs in New York City drivers

Kazaryan, Ani 24 October 2018 (has links)
PURPOSE: The purpose of this study was to investigate the potential relationship between alcohol and drug prevalence in drunk- and drug-impaired driving cases in New York City (NYC) between January 1, 2015 and December 31, 2017 and to determine how this prevalence has changed over time. The study also investigated the demographic characteristics of drivers to determine if there are certain groups who are consistently involved in alcohol and/or drug abuse while operating a motor vehicle. METHODS: This retrospective study determined the alcohol and drug prevalence in individual drivers represented as cases per year over three consecutive years. A total of 613 cases were included in the study for individuals, age 16 to 75 years old arrested for suspicion of driving while intoxicated (DWI) in NYC. Individual data collected included basic demographic information, time and day of incident, borough in which incident occurred, type of matrix used for toxicological analysis and the presence and absence of alcohol and/or drugs. Drug findings were combined into classes based on their likely effect and included the following categories: alcohol, antidepressants, cannabinoids, narcotic analgesics, sedatives, stimulants and other. RESULTS: Results from the study compared data over three consecutive years from DWI cases (2015 to 2017). In comparing prevalence of drug classes by year, the percent of cases tested positive for cannabinoids, narcotic analgesics and stimulants changed significantly from 2015 to 2017. Delta-9-tetrahydrocannabinol (THC), the active component of marijuana, was the most frequent individual drug identified using a screening method. The prevalence rate of cannabinoids increased significantly in 2017 to 43.0% from 32.5% the previous year and 29.3% in 2015. The narcotic analgesics prevalence rate increased significantly in 2016 to 28.5% from 13.4% in the previous year and slightly decreased to 26.9% in 2017. Comparison of stimulants by year showed a significant increase in 2017, 28.1% versus 19.0% (2016) versus 18.3% (2015). When comparing the 2017 results to the drugs tested for in 2015 and 2016, significantly higher daytime drug prevalence was found between the previous years and 2017. In evaluating race and drug use, white drivers were significantly more likely to test positive for sedatives and stimulants than other races. In Manhattan, there was a significantly higher alcohol detection rate compared to the other boroughs and in Staten Island there was a significantly higher narcotic analgesics detection rate. In comparing the top five individual drugs identified by borough, cannabinoids were the most common drug across all of the boroughs. Alprazolam and cocaine (identified by its metabolite, benzoylecgonine, 98% of the time) were the next most frequently encountered drugs alternating as the top two and three drugs identified in the following four boroughs: Manhattan, Queens, the Bronx, and Staten Island. Phencyclidine (PCP) (“angel dust”) was identified in the top five for Manhattan, the Bronx and Staten Island. A statistically significant negative association was found between cannabinoid-positive and alcohol-positive drivers. The percentage of drivers with a BAC greater than .08 g/dL was significantly lower among cannabinoid-positive drivers than those who tested negative for cannabinoids. Although there were no strong correlations between drug classes, sedatives were associated (according to significant correlations) most to other drugs (correlated to 6 out of 6 categories). CONCLUSIONS: This study summarizes the results of the first OCME FTL of NYC toxicological findings in DWI cases to estimate alcohol and drug-involved driving prevalence. It is important to note that this is a prevalence study and not a study that reports the risks associated with drugged-driving. Since many drugs may be detected long after its impairing effects are gone, the focus of this study was to merely convey the use of particular drugs in the driving population.
10

Are All THC-Dominant Cannabis Varieties the Same? Comparing the Phytochemistry and Bioactivity of Different THC-Dominant Cannabis Samples

Waldbillig, Adam 29 August 2022 (has links)
Cannabis sativa has a complex history of classification and traditional use. Cannabis sativa ssp. sativa and spp. indica are the two major lineages of cannabis and, through artificial selection, many strains or cultivars are found within each group are bred together to yield hybrid plants. New methods of classification based on Δ⁹-Tetrahydrocannbinol (THC) and Cannabidiol (CBD) content as well as minor cannabinoids and terpenes have emerged as a more effective classification of cannabis. However, the fidelity of cannabis varieties relative to their respective strain names and lineages (indica, sativa and hybrid) based on chemistry has been brought into question. THC and more recently CBD are collectively responsible for the psychoactive and therapeutic effects of cannabis and minor cannabinoids and terpenes are emerging as having their own unique bioactivity or synergistic effects in vitro. Considering the variation in cannabis chemical profile and infidelity to strain names or lineages, we investigated the cannabinoid, terpene and metabolomic profiles of 33 THC-dominant strains (113 samples) to evaluate existing and alternative chemistry-based classification systems using multivariate analyses. Here, we conclude that Indica-Sativa-Hybrid designations are insufficient in describing variation in cannabinoid, terpene and metabolomic data, and that a terpene-based profile classification revealed robust groupings in cannabinoid-terpene data. However, terpene profiles were not discernable in metabolomic data. To investigate how chemical complexity and variability impacts bioactivity, we compared the activity of cannabis extracts to that of pure THC (and CBD) to determine if THC alone is driving activity. THC, CBD, and plant extracts were tested in vitro for cytotoxicity in BEAS-2Bs cells and for cannabinoid receptor signalling activity using a human CB₁-HEK293 cell model. THC did not completely dictate 24-hour toxicity in BEAS-2B cells suggesting that other extract components (beyond THC and CBD) are contributing to cytotoxicity. While CBD alone was 2x more toxic than THC alone, THC:CBD do no predict toxic concentration. THC within extracts appeared to drive efficacy at CB₁ receptors by reducing intracellular cAMP accumulation but did not dictate variation in EC₅₀. THC in extract also appeared to increase percent cAMP reduction in cells regardless of low CBD content but a 1:1 balanced THC/CBD extract revealed reduced percent cAMP reduction. Pure compounds compared to extracts of the same THC/CBD ratio performed very similarly at CB1 receptors besides 1:1 extract preparation having reduced % reduction of cAMP compared to 1:1 pure compounds suggestive of NAM by extract components. Regression modelling of THC within extract revealed a significant positive relationship in % cAMP reduction (Emax) but no significance in TC₅₀ and EC₅₀. This work demonstrates the importance of rigorous analysis of cannabis chemistry as well as evaluation of extracts in bioactivity assays.

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