2 resultados para change detection analysis

em Glasgow Theses Service


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New psychoactive substances (NPSs) have appeared on the recreational drug market at an unprecedented rate in recent years. Many are not new drugs but failed products of the pharmaceutical industry. The speed and variety of drugs entering the market poses a new complex challenge for the forensic toxicology community. The detection of these substances in biological matrices can be difficult as the exact compounds of interest may not be known. Many NPS are sold under the same brand name and therefore users themselves may not know what substances they have ingested. The majority of analytical methods for the detection of NPSs tend to focus on a specific class of compounds rather than a wide variety. In response to this, a robust and sensitive method was developed for the analysis of various NPS by solid phase extraction (SPE) with gas chromatography mass spectrometry (GCMS). Sample preparation and derivatisation were optimised testing a range of SPE cartridges and derivatising agents, as well as derivatisation incubation time and temperature. The final gas chromatography mass spectrometry method was validated in accordance with SWGTOX 2013 guidelines over a wide concentration range for both blood and urine for 23 and 25 analytes respectively. This included the validation of 8 NBOMe compounds in blood and 10 NBOMe compounds in urine. This GC-MS method was then applied to 8 authentic samples with concentrations compared to those originally identified by NMS laboratories. The rapid influx of NPSs has resulted in the re-analysis of samples and thus, the stability of these substances is crucial information. The stability of mephedrone was investigated, examining the effect that storage temperatures and preservatives had on analyte stability daily for 1 week and then weekly for 10 weeks. Several laboratories identified NPSs use through the cross-reactivity of these substances with existing screening protocols such as ELISA. The application of Immunalysis ketamine, methamphetamine and amphetamine ELISA kits for the detection of NPS was evaluated. The aim of this work was to determine if any cross-reactivity from NPS substances was observed, and to determine whether these existing kits would identify NPS use within biological samples. The cross- reactivity of methoxetamine, 3-MeO-PCE and 3-MeO-PCP for different commercially point of care test (POCT) was also assessed for urine. One of the newest groups of compounds to appear on the NPS market is the NBOMe series. These drugs pose a serious threat to public health due to their high potency, with fatalities already reported in the literature. These compounds are falsely marketed as LSD which increases the chance of adverse effects due to the potency differences between these 2 substances. A liquid chromatography tandem mass spectrometry (LC-MS/MS) method was validated in accordance with SWGTOX 2013 guidelines for the detection for 25B, 25C and 25I-NBOMe in urine and hair. Long-Evans rats were administered 25B-, 25C- and 25I-NBOMe at doses ranging from 30-300 µg/kg over a period of 10 days. Tail flick tests were then carried out on the rats in order to determine whether any analgesic effects were observed as a result of dosing. Rats were also shaved prior to their first dose and reshaved after the 10-day period. Hair was separated by colour (black and white) and analysed using the validated LC-MS/MS method, assessing the impact hair colour has on the incorporation of these drugs. Urine was collected from the rats, analysed using the validated LC-MS/MS method and screened for potential metabolites using both LC-MS/MS and quadrupole time of flight (QToF) instrumentation.

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Background: Autoimmune encephalitis (AE) occurs in response to an antibody-mediated central nervous system disease and can lead to significant neurodisability. Prior research on family adjustment has described a reciprocal relationship between caregiver functioning, distress and clinical outcome in parents and children with encephalitis. There has been no previous research exploring the experiences of caregivers with a child with AE. Aims: To explore the perspectives of parents and/or caregivers with a child diagnosed with AE regarding (i) their own adjustment from hospital admission to post-discharge, and (ii) their experiences of care and service provision. Methods: A purposive sampling approach was used. Five parents of children with AE participated in a semi-structured interview exploring their experiences of caring for their child and service provision during acute care and post-discharge. Interpretative Phenomenological Analysis (IPA) was used to analyse the transcripts. Main findings and conclusions: Four shared super-ordinate themes with related subthemes emerged: (a) uncertainty, (b) managing our recovery, (c) changes in my child, (d) experiences of service provision. Participants reported emotional distress, often underpinned by recurrent experiences of uncertainty, and ‘loss’ of the previous child, and mediated by coping strategies and social support. While an overall positive experience of inpatient services was reported, parents often perceived post-discharge services as lacking in co-ordination, communication and formal follow-up, resulting in unmet support needs. Implications and recommendations for services, practitioners and future research are discussed.