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Dallas, TX, United States

Schwaninger A.E.,Saarland University | Meyer M.R.,Saarland University | Barnes A.J.,U.S. National Institute on Drug Abuse | Kolbrich-Spargo E.A.,U.S. National Institute on Drug Abuse | And 5 more authors.
Biochemical Pharmacology | Year: 2012

The R-and S-enantiomers of racemic 3,4-methylenedioxymethamphetamine (MDMA) exhibit different dose-concentration curves. In plasma, S-MDMA was eliminated at a higher rate, most likely due to stereoselective metabolism. Similar data were shown in various in vitro experiments. The aim of the present study was the in vivo investigation of stereoselective elimination of MDMA's phase I and phase II metabolites in human urine following controlled oral MDMA administration. Urine samples from 10 participants receiving 1.0 and 1.6 mg/kg MDMA separated by at least one week were analyzed blind by liquid chromatography-high resolution-mass spectrometry and gas chromatography-mass spectrometry after chiral derivatization with S-heptafluorobutyrylprolyl chloride. R/S ratios at C max were comparable after low and high doses with ratios >1 for MDMA, free DHMA, and HMMA sulfate, and with ratios <1 for MDA, free HMMA, DHMA sulfate and HMMA glucuronide. In the five days after the high MDMA dose, a median of 21% of all evaluated compounds were excreted as R-stereoisomers and 17% as S-stereoisomers. Significantly greater MDMA, DHMA, and HMMA sulfate R-enantiomers and HMMA and HMMA glucuronide S-stereoisomers were excreted. No significant differences were observed for MDA and DHMA sulfate stereoisomers. Changes in R/S ratios could be observed over time for all analytes, with steady increases in the first 48 h. R/S ratios could help to roughly estimate time of MDMA ingestion and therefore, improve interpretation of MDMA and metabolite urinary concentrations in clinical and forensic toxicology. © 2011 Elsevier Inc. Source

Thompson M.P.,University of Texas Southwestern Medical Center | Pinckard J.K.,University of Texas Southwestern Medical Center | Pinckard J.K.,Southwestern Institute of Forensic science
American Journal of Forensic Medicine and Pathology | Year: 2011

Thyrotoxic periodic paralysis is a rare and dramatic complication of hyperthyroidism. Thyrotoxic periodic paralysis classically presents with proximal lower limb weakness in the setting of hypokalemia and thyrotoxicosis. Thyrotoxic periodic paralysis represents an endocrine emergency with a rapidly ascending paralysis that can result in respiratory insufficiency, cardiac arrhythmias, and death if not accurately and rapidly diagnosed. We report a case of undiagnosed fatal thyrotoxic periodic paralysis presenting to the medical examiner. The diagnosis was made primarily by review of the clinical history. © 2011 by Lippincott Williams & Wilkins. Source

Lann M.A.,University of Colorado at Denver | Lovell M.A.,Childrens Hospital | Lovell M.A.,Southwestern Institute of Forensic science | Kleinschmidt-Demasters B.K.,University of Colorado at Denver
American Journal of Forensic Medicine and Pathology | Year: 2010

Acute hemorrhagic leukoencephalopathy (AHLE) is a rare, acute disorder characterized by perivenular demyelination and diffuse hemorrhagic necrosis of the central nervous system. AHLE is thought to represent a hyperacute form of acute disseminated encephalomyelitis. AHLE is associated with a greater morbidity and mortality and, fortunately, is much less common than acute disseminated encephalomyelitis. Since most cases of AHLE result in patient demise, forensic pathologists should be cognizant of this entity and consider it in their differential diagnosis.Here we describe an interesting case of a previously healthy 11-year-old boy who initially complained of vague gastroenteritis-like symptoms while visiting a mountain lake. The boy's symptoms evolved to include severe headache and dizziness, necessitating a visit to a rural emergency department. He presented with focal neurologic findings, and head computed tomography (CT) scan confirmed thalamic edema. Cerebrospinal fluid analysis was suggestive of infectious etiology, and multiple empiric therapies were initiated. He was transferred to our institution, and his clinical status continued to worsen. Given the poor prognosis, the family requested withdrawal of supportive care. On day 14 of symptoms the boy succumbed to his illness. An autopsy was requested to further characterize the proximate cause of death.AHLE often presents with abrupt onset of fever, neck stiffness, seizure, and/or focal neurologic signs several days following a viral illness or vaccination. Thus, AHLE can clinically mimic a direct central nervous system infection or a toxic ingestion. AHLE has a very poor prognosis, with rapid deterioration and death usually occurring within days to one week after onset of symptoms. The cause for AHLE is unclear. An autoimmune pathophysiology is likely, with immune cross-reactivity between myelin basic protein moieties and various infectious agent antigens. Treatment for AHLE is not well-established; some authors describe in recent literature that a combination of immunosuppressant medications and/or therapeutic plasma exchange may be of benefit in treating AHLE. Copyright © 2010 by Lippincott Williams & Wilkins. Source

Schwaninger A.E.,Saarland University | Meyer M.R.,Saarland University | Barnes A.J.,U.S. National Institute on Drug Abuse | Kolbrich-Spargo E.A.,U.S. National Institute on Drug Abuse | And 5 more authors.
Clinical Chemistry | Year: 2011

BACKGROUND: 3,4-Methylendioxymethamphetamine (MDMA) is excreted in human urine as unchanged drug and phase I and II metabolites. Previous urinary excretion studies after controlled oral MDMA administration have been performed only after conjugate cleavage. Therefore, we investigated intact MDMA glucuronide and sulfate metabolite excretion. METHODS: We used LC-high-resolution MS and GC-MS to reanalyze blind urine samples from 10 participants receiving 1.0 or 1.6 mg/kg MDMA orally. We determined median C max, t max, first and last detection times, and total urinary recovery; calculated ratios of sulfates and glucuronides; and performed in vitro-in vivo correlations. RESULTS: Phase II metabolites of 3,4-dihydroxymethamphetamine (DHMA), 4-hydroxy-3-methoxymethamphetamine (HMMA), 3,4-dihydroxyamphetamine (DHA), and 4-hydroxy-3-methoxyamphetamine were identified, although only DHMA sulfates, HMMA sulfate, and HMMA glucuronide had substantial abundance. Good correlation was observed for HMMA measured after acid hydrolysis and the sum of unconjugated HMMA, HMMA glucuronide, and HMMA sulfate (R 2 = 0.87). More than 90% of total DHMA and HMMA were excreted as conjugates. The analyte with the longest detection time was HMMA sulfate. Median HMMA sulfate/glucuronide and DHMA 3-sulfate/4-sulfate ratios for the first 24 h were 2.0 and 5.3, respectively, in accordance with previous in vitro calculations from human liver microsomes and cytosol experiments. CONCLUSIONS: Human MDMA urinary metabolites are primarily sulfates and glucuronides, with sulfates present in higher concentrations than glucuronides. This new knowledge may lead to improvements in urine MDMA and metabolite analysis in clinical and forensic toxicology, particularly for the performance of direct urine analysis. © 2011 American Association for Clinical Chemistry. Source

Lann M.A.,Southwestern Institute of Forensic science | Martin A.,Denver Office of the Medical Examiner
Journal of Forensic Sciences | Year: 2010

Deaths involving sensory deprivation tanks are very rare. We describe a unique case in which a previously healthy 50-year-old woman apparently died while floating in a sensory deprivation tank at her residence. Autopsy failed to reveal definitive anatomical abnormalities pointing to the cause of death. A thorough scene investigation, full medicolegal autopsy to include toxicological analyses, and a complete investigation into the equipment at the scene, were conducted. Blood toxicologic studies were significant for the presence of ethanol (0.27%) and a mixture of over-the-counter sedating medications and prescription drugs. The cause of death was ruled as acute mixed drug and ethanol toxicity combined with probable environmental hyperthermia; manner was accident. This case report will help the forensic community understand the intended use of flotation tanks, as well as possible risks associated with improper use. © 2010 American Academy of Forensic Sciences. Source

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