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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

Forensic analysis of the psychoactive alkaloids harmine and harmaline in peganum harmala seeds

Thompson, Alex Frances January 2013 (has links)
The Peganum harmala plant is a flowering shrub that produces small, dark brown seeds in pods. These seeds contain the hallucinogenic alkaloids harmine and harmaline. As such, they have been historically used for shamanic rites and folk medicine. Presently, P. harmala seeds are commercially available and subject to no legal restrictions in the United States. This has allowed for the recreational use and abuse of these hallucinogenic seeds or seed extracts made with household chemicals. Overdose cases from excessive consumption of seeds or seed extracts have been reported. Overdose patients present with hallucinations, tremors, agitation, tachycardia, and gastric distress. Severe overdose cases have resulted in hospitalization for respiratory depression and coma. The goal of this research was to develop a protocol for forensic analysis of suspected P. harmala seeds. Physical examination was selected as a quick, cost-effective preliminary method to screen seeds. P. harmala seeds are, on average, approximately 2.3 ± 0.3 mm long and 1.0 ± 0.2 mm thick, with an average Feret’s diameter of 2.8 ± 0.3 mm. The mean mass of one seed is 2.5 ± 0.2 mg. The seeds are dark brown, irregularly shaped, and have a pitted surface. Seeds matching these descriptors can be further analyzed to detect harmine and harmaline. Direct analysis in real time (DART) allows for very rapid mass spectral analysis of P. harmala seeds. Ions corresponding to harmine and harmaline can be detected when an intact seed is placed in front of the DART ion source, and higher levels of harmine and harmaline are observed when a seed cut in half to reveal interior surfaces is analyzed. Solvent extraction of crushed seeds using ethanol followed by gas chromatography – mass spectrometry allows for confirmation of the presence of harmine and harmaline in suspected seeds. When selected ion monitoring is used, this method is able to detect harmine and harmaline in a sample consisting of a single seed. Infrared spectra of harmine and harmaline standards, crushed P. harmala seeds, and solid material obtained from evaporating off the solvent from an extraction of crushed seeds were obtained. Infrared spectroscopy can be used to distinguish between pure harmine and harmaline, but is a poor choice for analysis of samples containing a mixture of harmine and harmaline, such as P. harmala seeds. In conclusion, physical characterization, direct analysis in real time, solvent extraction, and gas chromatography – mass spectrometry are recommended techniques for the forensic analysis of P. harmala seeds.
2

Probing the root exudation of harmala alkaloids from Syrian rue

Borton, Corianna M. January 2019 (has links)
No description available.
3

Naturens Läkemedel : Harmin mot cancer?

Berthelsen, Isabell January 2016 (has links)
Harmine is a beta-carboline present in medical plants such as Peganum harmala that have been used traditionally as anticancer therapy. In this study, the aim was to examine if it really does have an effect on cancer and if so, mechanism of action. To do so several earlier studies on the subject have been examined. The result is promising but there is still a lot to study on the subject. Harmine really does inhibit tumour growth. It has been tested on both cellcultures and mice and has proven to decrease tumourgrowth significantly with little effect on normal cells. There have also been studies were harmine has been modified to be more efficient and less harmful. One way to make Harmine more effective is to put a 2-amino-2deoxy-D-glucose on the molecule. Since the cancer cell uses a lot of energy for its growth a big proportion of the medicine will end up here. Another way is to attach a methionin-group to it. This is also taken up exccessively by the cancer cells. Substitution in different areas may reduce it’s toxicity; Substitution with a formiat at R3 for example decreased its toxicity so that no side effects were seen in the mice in the study whereas harmine in large doses gave neurotoxic symptoms. Harmines antitumour activity seems to be due to several mechanisms of action. For example a higher level of p53 has been observed efter treatment with harmine. P53 has been called ”the guardian of the genome” because of its role in preventing genome mutation. In some studies a decrease in vascular endothelial growth factor (VEGF) has also been seen. This is an important factor for the growth of new vessels toward the tumour-site. A reduction in COX-2 has also been seen. Inhibition of COX-2, for example by NSAID, is associated with lower risk for coloncancer. A fourth possible mechanism of action could be a decrease or inhibtion of CDKs/Cyklins wich are necessary for the cellcycle-progression. Although a promising substance, there is still a lot to study. It would be interesting to se comparations to established drugs on the market and also what the long term side effects of Harmine could be. The studies so far have only been done under a short period of time, i.e., weeks or months.
4

Identifying Aryl Hydrocarbon Receptor Modulators from a Natural Source

El Gendy, Mohamed, A M Unknown Date
No description available.

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