Publications by authors named "Warren C Samms"

4 Publications

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Corrigendum to "Case Reports of Fatalities Involving Tianeptine in the United States".

J Anal Toxicol 2019 03;43(2):e1

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http://dx.doi.org/10.1093/jat/bky086DOI Listing
March 2019

Case Reports of Fatalities Involving Tianeptine in the United States.

J Anal Toxicol 2018 09;42(7):503-509

Harris County Institute of Forensic Sciences, 1861 Old Spanish Trail, Houston, TX, USA.

Tianeptine is a tricyclic anti-depressant that is also known to have opioid receptor activity. We present two fatal cases of tianeptine intoxication in Texas in which tianeptine was used recreationally. The first case involved a 28-year-old white male found alone on the floor of his locked residence. He had a history of drug abuse but no other toxicological findings. The second case involved a 30-year-old white male found on the floor of the bathroom in his home. Drug paraphernalia and bags labeled as tianeptine powder were found at both scenes. In response to the first case, our laboratory developed a method for quantitation of tianeptine by LC-MS-MS. This method was then validated according to SWGTOX guidelines for specificity, calibration model, limit of detection, limit of quantitation, accuracy, precision, ion suppression, and carryover. This method was successfully used to determine tianeptine concentrations in postmortem blood in two cases. In these cases, tianeptine was measured at 2.0 mg/L and 8.4 mg/L. These represent the first known tianeptine fatalities in Texas and in the United States.
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http://dx.doi.org/10.1093/jat/bky023DOI Listing
September 2018

Analysis of alprazolam by DART-TOF mass spectrometry in counterfeit and routine drug identification cases.

J Forensic Sci 2011 Jul 6;56(4):993-8. Epub 2011 Apr 6.

Harris County Institute of Forensic Sciences, 1885 Old Spanish Trail, Houston, TX 77054, USA.

The high prevalence of alprazolam abuse translates to an increased workload for crime laboratories in characterizing seized tablets. These tablets may originate as diverted pharmaceuticals or counterfeited mimics, so efficient analytical techniques should provide confirmatory data while minimizing destruction of evidence. We offer the first report of a validated forensic method for confirming alprazolam tablets by direct analysis in real time-time of flight (DART-TOF) mass spectrometric analysis. This technique provides rapid identification of target analytes with minimal sample preparation, allowing direct analysis in the atmospheric sample gap. Selectivity is achieved through high resolution and mass accuracy, unique ion fragments, and chlorine isotopic ratios. This method utilizes fragmentation in two separate voltage functions to observe the alprazolam pseudo molecular ion at 309.09070 using 40 V and major ion fragments of 281.07197 and 205.07657 at 120 V. These parameters allow our laboratory to confirm alprazolam tablets efficiently, without compromising quality forensic standards.
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http://dx.doi.org/10.1111/j.1556-4029.2011.01767.xDOI Listing
July 2011

Perturbation of dopamine metabolism by 3-amino-2-(4'-halophenyl)propenes leads to increased oxidative stress and apoptotic SH-SY5Y cell death.

Mol Pharmacol 2007 Sep 18;72(3):744-52. Epub 2007 Jun 18.

Department of Chemistry, Wichita State University, Wichita, Kansas, USA.

We have recently characterized a series of 3-amino-2-phenyl-propene (APP) derivatives as reversible inhibitors for the bovine adrenal chromaffin granule vesicular monoamine transporter (VMAT) that have been previously characterized as potent irreversible dopamine-beta-monooxygenase (DbetaM) and monoamine oxidase (MAO) inhibitors. Halogen substitution on the 4'-position of the aromatic ring gradually increases VMAT inhibition potency from 4'-F to 4'-I, parallel to the hydrophobicity of the halogen. We show that these derivatives are taken up into both neuronal and non-neuronal cells, and into resealed chromaffin granule ghosts efficiently through passive diffusion. Uptake rates increased according to the hydrophobicity of the 4'-substituent. More importantly, these derivatives are highly toxic to human neuroblastoma SH-SY5Y but not toxic to M-1, Hep G2, or human embryonic kidney 293 non-neuronal cells at similar concentrations. They drastically perturb dopamine (DA) uptake and metabolism in SH-SY5Y cells under sublethal conditions and are able to deplete both vesicular and cytosolic catecholamines in a manner similar to that of amphetamines. In addition, 4'-IAPP treatment significantly increases intracellular reactive oxygen species (ROS) and decreases glutathione (GSH) levels in SH-SY5Y cells, and cell death is significantly attenuated by the common antioxidants alpha-tocopherol, N-acetyl-l-cysteine and GSH, but not by the nonspecific caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone. DNA fragmentation analysis further supports that cell death is probably due to a caspase-independent ROS-mediated apoptotic pathway. Based on these and other findings, we propose that drastic perturbation of DA metabolism in SH-SY5Y cells by 4'-halo APP derivatives causes increased oxidative stress, leading to apoptotic cell death.
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http://dx.doi.org/10.1124/mol.107.035873DOI Listing
September 2007