Forensic Toxicology最新文献

Purpose: Serum caffeine concentration is an indicator of caffeine intoxication; however, it is difficult to measure it in most emergency departments. We developed a simple estimation method using a point-of-care test kit for urinary caffeine.

Methods: Caffeine-spiked human serum (100, 50, 25, and 10 µg/mL) was diluted 10-, 20-, 50-, and 100-fold with phosphate-buffered saline and applied to the kit. After 5 min incubation, the kit was scanned by a flatbed scanner and the membrane image was processed with ImageJ.

Results: When the 20-fold diluted serum was applied, serum samples with initial caffeine concentration ≤ 25 and ≥ 50 µg/mL were caffeine-negative and -positive, respectively. When the 100-fold diluted serum was applied, none of the caffeine-spiked serum samples gave positive results. Therefore, we proposed the following test procedure: (i) 20-fold diluted serum was initially tested and (ii) 100-fold diluted serum was additionally tested when the initial result was caffeine positive. Using this procedure, caffeine concentration is expected to be classified into three levels: ≤ 25, > 25- ≤ 100, and > 100 µg/mL, which almost correspond to no or mild, severe, and potentially fatal intoxication, respectively. The test procedure was validated using postmortem heart blood from two cases of fatal caffeine intoxication (caffeine concentration: 276 and 175 µg/mL) and two cases of other intoxication.

Conclusions: Our developed method using point-of-care urinary caffeine test kits enabled simple estimation of serum caffeine concentration.

Purpose: The abusive consumption of illegal E-cigarettes containing etomidate (ET) can have a significant impact on public mental and physical well-being. The purpose of this study is to establish a rapid quantitative method using ultra-high-performance liquid chromatography/tandem mass spectrometry (UHPLC-MS/MS) for the targeted screening of etomidate (ET) and its metabolite etomidate acid (ETA) in hair samples.

Methods: A 1 mL methanol solution containing the internal standard ET-d₅ at a concentration of 50 pg/mg was added to 20 mg of hair and milled below 4 °C. After centrifugation, 5 μL of the supernatant was injected into a UHPLC-MS/MS system.

Results: The limit of detection (LOD) and limit of quantification (LOQ) were determined to be 1 pg/mg and 10 pg/mg, respectively, for ET, and 10 pg/mg and 25 pg/mg, respectively, for ETA. Calibration curves for all analytes showed good linearity (r > 0.997), indicating a reliable method. Accuracies were between 92.12% and 110.72%. Intra-day and inter-day precision for all analytes at all concentration levels were below 10.13%. Analyte recoveries ranged from 86.90% to 101.43%, with a matrix effect ranging from -18.55% to -14.93%.

Conclusions: The validated method was successfully used to analyze 105 hair samples from suspected ET users. Of these, 50 tested positive for ET and 43 tested positive for ETA above the LOQ. This demonstrates the effectiveness of the developed UHPLC-MS/MS method in detecting ET and ETA in hair samples, which could be instrumental in addressing the issue of illegal E-cigarette abuse and its impact on public health.

Purpose: The most commonly associated substance found in Ecstasy tablets is MDMA (3,4-methylenedioxymethamphetamine). In our study, we showed how the composition of psychoactive ingredients in Ecstasy tablets seized on the drug market in Poland has changed in the years 2005-2020.

Methods: The study material consisted of nearly 20,000 single Ecstasy tablets seized by representatives of law enforcement (the police, prosecutors) from 2005 to 2020 and analysed by the Institute of Forensic Research, Krakow, Poland. The analysis of the tablets was carried out by gas chromatography-mass spectrometry (GC-MS), high-performance liquid chromatography with diode array detection (HPLC-DAD) and ultra-high-performance liquid chromatography with photodiode array detection (UHPLC-PDA).

Results: Currently, new types of MDMA tablets are introduced onto the market, available in various colours and shapes. Our study showed that tablets sold on the street as Ecstasy have variable purity and sometimes contain little or no MDMA. The mean content of MDMA in one tablet seized in 2005-2011 decreased from 90 to 50 mg. In 2013, Ecstasy tablets with a very high MDMA content (average 195 mg per tablet) appeared on the market, but in the next 2 years, the MDMA content decreased again. From 2016, the average MDMA content began to rise again, ranging from 60 to 280 mg.

Conclusion: Tablets sold as Ecstasy also contained completely different psychoactive substances, including new psychoactive substances (NPS) (found in almost 20% of all examined tablets sold as Ecstasy) belonging to different chemical groups or their dangerous combinations (i.e. phenylethylamines, piperazines, tryptamines, cathinones, arylalkylamines, arylcyclohexylamines and piperidines). Such a large variety of psychoactive substances in Ecstasy tablets is associated with a high risk for users unaware of their composition.

Background: The widespread misuse of synthetic cannabinoids (SCs) has led to a notable increase in reported adverse effects, raising significant health concerns. SCs use has been particularly associated with acute kidney injury (AKI). However, the pathogenesis of SCs-induced AKI is not well-understood.

Methods: We investigated the nephrotoxic effect of acute administration of N-[(1S)- 1-(aminocarbonyl)-2-methylpropyl]-1-[(4-fluorophenyl)methyl]-1H-indazole-3-carboxamide (AB-FUBINKA) (3 mg/kg for 5 days) in mice. Various parameters of oxidative stress, inflammation, and apoptosis have been quantified. The expressions of mitochondrial complexes (I-V) in renal tissues were also assessed.

Results: Our findings showed that AB-FUBINACA induced substantial impairment in the renal function that is accompanied by elevated expression of renal tubular damage markers; KIM-1 and NGAL. Administration of AB-FUBINACA was found to be associated with a significant increase in the expression of oxidative stress markers (iNOS, NOX4, NOX2, NOS3) and the level of lipid peroxidation in the kidney. The expression of pro-inflammatory markers (IL-6, TNF-alpha, NF-kB) was also enhanced following exposure to AB-FUBINACA. These findings were also correlated with increased expression of major apoptosis regulatory markers (Bax, caspase-9, caspase-3) and reduced expression of mitochondrial complexes I, III, and IV.

Conclusion: These results indicate that AB-FUBINACA can trigger oxidative stress and inflammation, and activate caspase-dependent apoptosis in the kidney, with these processes being possibly linked to disruption of mitochondrial complexes and could be an underlying mechanism of SCs-induced nephrotoxicity.

Purpose: Diagnosis of drug intoxication in the medico-legal autopsy is challenging due to many factors such as non-specific clinical features and non-specific, inconclusive autopsy findings, etc. Thus, deaths due to drug intoxication can be misclassified in a low-resource setting where post-mortem toxicology testing is selective. The paper presents a fatal case of unrecognized nifedipine intoxication in an adult where the manner of death was undetermined after extensive investigation.

Method: The liquid-liquid extraction using chloroform was carried out on a blood sample spiked with nifedipine. Subsequently, the post-mortem blood sample was analyzed and quantified using gas chromatography-mass spectrometry with electron ionization technique.

Results: The patient before death had symptoms, such as trismus, vomiting, and dizziness. The initial blood pressure and pulse rate were 94/56 mm Hg and 110 beats per minute, respectively. The respiratory rate was 20 breaths per minute. The post-mortem examination revealed no pathological changes or injuries in any organs. Upon histopathological examination, no significant findings that could have led to death were observed in any of the organs. The level of nifedipine in the peripheral blood, 0.645 μg/ml was determined to be either  close to or exceeding the reported fatal dose. The cause of death was ascertained as acute nifedipine intoxication.

Conclusion: It is crucial to accurately determine the cause of death in cases that pose a significant threat to public health. This case highlights the challenges faced by forensic pathologists in scientifically ascertaining the cause of death accurately, especially in intoxication deaths, and the importance of comprehensive toxicology testing services including analytical toxicology for the integrity of the medico-legal death investigation system.

Purpose: The metabolic pathways of APP-CHMINACA were characterized to select the markers of intake for implementation into analytical assays used by the clinical and forensic communities. We have combined the evidences obtained by both in vitro experiments and administration studies on mice.

Methods: APP-CHMINACA was incubated with either human or mouse liver microsomes. Urine and blood samples were collected at different time points from mice after injection of a 3 mg/kg dose of the test compound. Samples were analyzed using liquid chromatography-tandem mass spectrometry.

Results: The in vitro studies allowed to isolate eight different metabolic reactions, formed by two metabolic routes, with no differences between human and mouse liver microsomes. The main biotransformation route involved the hydrolysis of the distal amide group and the subsequent hydroxylation on the cyclohexyl-methyl ring. The second route involved multiple hydroxylation of the parent compound, followed by reduction to generate minor metabolites. In blood samples, the most abundant substances identified were APP-CHMINACA unchanged and the metabolites formed by the hydrolysis of the distal amide together with its hydroxylated products. In urine samples, four metabolites formed following the hydroxylation of the distal amide hydrolysis metabolite were detected as the most abundant and long-term metabolites.

Conclusions: The outcomes of our study showed that the most suitable markers to detect the intake of APP-CHMINACA in blood and urine samples in the framework of toxicological, clinical and forensic investigations were the metabolite formed by the hydrolysis of the distal amide and its hydroxylated products.

Purpose: The goal of the current study was to clarify the potential molecular mechanism underlying the protective effects of silymarin (SIL) administration against diazinon-induced subacute nephrotoxicity, with a special emphasis on the role of the Kelch-like-associated protein-1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2)-heme oxygenase-1 (HO-1) signaling pathway in minimizing the oxidative stress induced by diazinon (DZN).

Methods: Five equal groups of thirty adult male Wistar rats were created at random. Group 1 (G1) was maintained under typical control conditions and administered saline intragastrically (I/G) once daily for 4 weeks; G2 was administered olive oil I/G for 4 weeks; G3 was I/G administered silymarin daily for 4 weeks; G4 was I/G administered diazinon daily for 4 weeks. G5 was I/G administered silymarin daily 1 h before the I/G administration of the diazinon for 4 weeks. Blood samples were collected at the end of the experiment for the determination of complete blood cell count, and kidney function tests. Kidney specimens were collected for the evaluation of the oxidative markers, mRNA gene expression, protein markers, and histopathological examination.

Results: SIL reduced the renal dysfunction caused by DZN by restoring urea and creatinine levels, as well as oxidative indicators. Although the expression of Keap-1 was also elevated, overexpression of Nrf2 also enhanced the expression of HO-1, a crucial target enzyme of Nrf2.

Conclusions: SIL is hypothesized to potentially aid in the prevention and management of nephrotoxicity caused by DZN.

Purpose: This study examines the interaction between benzoylmesaconine (BMA) and hen egg white lysozyme (HEWL) under various physiological conditions, aiming to determine how BMA affects the HEWL's structure and function.

Methods: Several analytical techniques were used, including tryptophan assay, light scattering, thioflavin T (ThT)-binding assay, dynamic light scattering, 8-anilino-1-naphthalenesulfonic acid (ANS)-binding assay, circular dichroism (CD) spectroscopy, enzyme activity assay, and molecular docking.

Results: The tryptophan assay displayed a concentration-dependent decrease in tryptophan fluorescence, showing an interaction between BMA and HEWL. Light scattering and ThT-binding assays confirmed increased protein aggregation and amyloid fibril formation, while the ANS-binding assay demonstrated altered exposed hydrophobic regions, implying structural changes. CD spectroscopy showed a reduction in α-helix content, indicating conformational alterations, and enzyme activity assays showed a loss of lytic function due to structural distortion. Finally, molecular docking identified significant bonds and hydrophobic interactions between BMA and HEWL residues.

Conclusions: BMA binding induces structural changes in proteins, forming small oligomers and amyloid fibrils that decrease HEWL enzymatic activity and disrupt functional integrity.

Purpose: Cytisine is the active ingredient in preparations used for smoking cessation. Its popularity is attributed to its low cost, efficacy, and low incidence of adverse effects. Additionally, its easy over-the-counter availability is also significant. This accessibility makes it a potential substance for use in suicidal attempts. The aim of this study was to develop a method for the determination of cytisine in biological material for use in clinical and forensic toxicology, and to apply this method in authentic cases.

Methods: Biological samples were subjected to liquid-liquid extraction using cytisine-d₄ as an internal standard. Analyses were performed using a Hydrophilic Interaction Liquid Chromatography (HILIC) column with the technique of ultra-high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry.

Results: For both matrices (blood and urine), the linear concentration range was 5-1000 ng/mL. The method met all validation requirements. The concentration of cytisine in a man taking it for smoking cessation in post-mortem materials was 21.4 ng/mL in blood, 958.9 ng/mL in urine, ca. 30 ng/mL in vitreous humor, and ca. 40 ng/mL in bile. In contrast, for a man with cytisine intoxication, the concentration was 174.6 ng/mL in blood and > 10,000 ng/mL in urine. In both cases, no N-methylcytisine was detected.

Conclusions: The developed method can be used for the determination of cytisine in post-mortem biological matrices as well as for clinical purpose. We presented the concentrations of cytisine in the post-mortem biological samples of a man taking cytisine for smoking cessation and of a man with suicidal cytisine poisoning.