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1.
Sud Med Ekspert ; 64(6): 39-42, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34814644

RESUMO

The objective of this work is to evaluate the possibility of biological fluids sample preparation in forensic toxicology using a molecularly imprinted sorbent based on acrylic acid derivatives. Phenylpiracetam has similar physicochemical properties to those of pyrrolidinophenone derivatives and reproduces their behavior during solid-phase extraction. The phenylpiracetam recovery from blood and urine model samples is 75% for concentration range of 100.0-6000.0 ng/ml. The accuracy of phenylpiracetam extraction does not exceed ±12% for blood samples and ±6% for urine samples. The repeatability is no more than 16% and 13% for blood and urine samples, respectively. A study of the cross-reactivity of the molecularly imprinted sorbent with some drugs showed the selectivity of the sample preparation procedure.


Assuntos
Impressão Molecular , Toxicologia Forense , Extração em Fase Sólida
2.
Sud Med Ekspert ; 64(5): 10-12, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34644026

RESUMO

Professor R.V. Babakhanyan - Head of the Department of Forensic Medicine and Law, Pavlov First Saint Petersburg State Medical University is one of the notable teachers and scientists among the St. Petersburg forensic experts. Author of 500 published works, co-author of 6 monographs. He trained 28 candidates of medical sciences. The range of scientific interests - topical issues of forensic toxicology and injuries from non-lethal self-defense weapons.


Assuntos
Medicina Legal , Toxicologia Forense , História do Século XX , Humanos , Masculino
3.
Molecules ; 26(17)2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34500772

RESUMO

Dried urine spots (DUS) represent a potential alternative sample storage for forensic toxicological analysis. The aim of the current study was to develop and validate a liquid chromatographic tandem mass spectrometric procedure for the detection and quantitative determination of cannabinoids and metabolites in DUS. A two-step extraction was performed on DUS and urine samples. An LC-MS/MS system was operated in multiple reaction monitoring and positive polarization mode. The method was checked for sensitivity, specificity, linearity, accuracy, precision, recovery, matrix effects and carryover. The method was applied to 70 urine samples collected from healthy volunteers and drug addicts undergoing withdrawal treatment. The method was successfully developed for DUS. LODs lower than 2.0 ng/mL were obtained for all the monitored substances. All the validation parameters fulfilled the acceptance criteria either for DUS or urine. Among the real samples, 45 cases provided positive results for at least one compound. A good quali-quantitative agreement was obtained between DUS and urine. A good stability of THC, THCCOOH and THCCOOH-gluc was observed after a 24 h storage, in contrast to previously published results. DUS seems to provide a good alternative storage condition for urine that should be checked for the presence of cannabinoids and metabolites.


Assuntos
Canabinoides , Toxicologia Forense , Detecção do Abuso de Substâncias , Urinálise , Canabinoides/metabolismo , Canabinoides/urina , Cromatografia Líquida , Humanos , Espectrometria de Massas em Tandem
4.
Forensic Sci Int ; 327: 110978, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34481114

RESUMO

Propranolol is a widely used beta-blocker mainly prescribed for the treatment of hypertension and other cardiac conditions. This medicine is also a frequent finding in drug screens, but little is known about its post-mortem toxicological profile. Our aim was to examine all post-mortem toxicology cases positive for propranolol in a three-year period, between 2016 and 2018 in Finland, and to compare these cases to those positive for metoprolol, another beta-blocker commonly used to treat cardiac diseases. There were 179 cases positive for propranolol and 416 for metoprolol in the study period. In the majority of propranolol cases (53%), the drug concentration in the blood was above the typical therapeutic range, but among the metoprolol cases this proportion was 18%. Propranolol was significantly more common than metoprolol in fatal poisonings, suicides and in cases with a history of drug abuse. Alcohol, benzodiazepines, antipsychotics and antidepressants were significantly more often detected in propranolol cases than in metoprolol cases. The deceased positive for propranolol were significantly younger than those positive for metoprolol. Cardiovascular diseases as the underlying cause of death were significantly more common among the metoprolol cases than among the propranolol cases. Our results showed significant differences between the propranolol group and the metoprolol group in post-mortem toxicology cases. The two drugs were used by two very different groups of people, with propranolol use being associated with psychiatric conditions.


Assuntos
Antagonistas Adrenérgicos beta/sangue , Bases de Dados Factuais , Toxicologia Forense/estatística & dados numéricos , Metoprolol/sangue , Propranolol/sangue , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/epidemiologia , Causas de Morte , Feminino , Finlândia/epidemiologia , Humanos , Masculino , Transtornos Mentais/epidemiologia , Pessoa de Meia-Idade , Detecção do Abuso de Substâncias/estatística & dados numéricos
5.
Forensic Sci Int ; 327: 110975, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34478894

RESUMO

Pholcodine is an opioid antitussive reputed for its low toxicity and absence of addictive effect. We report three cases of pholcodine intoxication with fatal outcome. Large concentrations of pholcodine were quantified by gas chromatography coupled to mass spectrometry (GC/MS) in peripheral postmortem blood (respectively 2890 ng/mL, 979 ng/mL and 12,280 ng/mL). Segmental hair analyses by GC/MS and detected pholcodine in three 1.5-2 cm segments (38-161 ng/mg, 8.54-41.6 ng/mg, and 0.26-2.66 ng/mg, respectively). These findings underline that pholcodine can be involved in fatal poisoning and raise the question of misuse or abuse and of taking account of this drug in opioid overdose prevention policies.


Assuntos
Antitussígenos/envenenamento , Codeína/análogos & derivados , Toxicologia Forense , Morfolinas/envenenamento , Antitussígenos/sangue , Antitussígenos/urina , Autopsia , Codeína/sangue , Codeína/envenenamento , Codeína/urina , Evolução Fatal , Feminino , Análise do Cabelo , Humanos , Pessoa de Meia-Idade , Morfolinas/sangue , Morfolinas/urina , Adulto Jovem
6.
Molecules ; 26(18)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34577109

RESUMO

One of the recently evolving methods for cyanide determination in body fluids is GC-MS, following extractive alkylation with pentafluorobenzyl bromide or pentafluorobenzyl p-toluenesulfonate. The aim of this study was to improve previous GC methods by utilizing a triple quadrupole mass spectrometer, which could enhance selectivity and sensitivity allowing for the reliable confirmation of cyanide exposure in toxicological studies. Another purpose of this study was to facilitate a case investigation including a determination of cyanide in blood and to use the obtained data to confirm the ingestion of a substance, found together with a human corpse at the forensic scene. The blood samples were prepared following extractive alkylation with a phase transfer catalyst tetrabutylammonium sulfate and the PFB-Br derivatization agent. Optimal parameters for detection, including ionization type and multiple reaction monitoring (MRM) transitions had been investigated and then selected. The validation parameters for the above method were as follows-linear regression R2 = 0.9997 in the range of 0.1 µg/mL to 10 µg/mL; LOD = 24 ng/mL; LOQ = 80 ng/mL and an average recovery of extraction of 98%. Our study demonstrates the first attempt of cyanide determination in blood with gas chromatography-tandem mass spectrometry. The established method could be applied in forensic studies due to MS/MS confirmation of organic cyanide derivative and low matrix interferences owning to utilizing negative chemical ionization.


Assuntos
Toxicologia Forense , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas em Tandem , Cianetos
7.
Fa Yi Xue Za Zhi ; 37(3): 402-401, 2021 Jun.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34379912

RESUMO

Abstract: Mass spectrometry imaging (MSI) is a new imaging technology that can simultaneously detect and record the spatial distribution information of multiple molecules on the sample surface without labeling. The main principle of MSI is to combine mass spectrometry with imaging technology and irradiate the sample slice with ion beam or laser to ionize the molecules on its surface, obtain the mass spectrometry signal through the detector, convert the obtained data into pixel points by the imaging software, and then construct the spatial distribution image of the target compound on the tissue surface. The sample preparation for MSI include: sample collection and storage, tissue section, tissue pretreatment, selection and application of matrix. At present, this technology has been widely used in the fields of biomedicine, new drug development and proteomics, and its application in the field of forensic toxicology has also gradually attracted attention. This article reviews the principles and sample preparation process of MSI, describes the application of MSI in abused substances and metabolites of various material matrices, herbal mixtures, latent fingerprints, hair and animal and plant tissues, and discusses the prospects of the application of this technology in forensic toxicology, in order to provide ideas and references for the application of MSI technology in forensic toxicology.


Assuntos
Diagnóstico por Imagem , Proteômica , Animais , Toxicologia Forense , Humanos , Espectrometria de Massas , Plantas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
8.
J Forensic Leg Med ; 82: 102231, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34375840

RESUMO

In forensic toxicology, alternative biological materials are very useful and important, e.g. in the case of lack of basic body fluids. One alternative biological material is cerebrospinal fluid (CSF). The procedures of the collection of biological material during the autopsy are performed in accordance with local, usually national recommendations, which most often require updating. It is very difficult to assess the possibility of using CSF as an alternative biological material for toxicological studies for the presence of drugs, intoxicants, including new psychoactive substances (commonly known as designer drugs), psychotropic substances, and ethyl alcohol, based on current data. Previous research suggests that CSF may be useful in toxicological studies, but these aspects need to be investigated more carefully because studies have collected CSF from different sites and often the results of different authors are not comparable. It would be necessary to prepare guidelines, e.g. the site of CSF collection that may influence the results of quantitative analysis. It would also be necessary to replicate some studies with a different collection site or a more recent analytical technique, e.g. for comparative testing of blood ethanol and cerebrospinal fluid. Cerebrospinal fluid can be a valuable information carrier in the absence of classic biological material from an autopsy. Investigating these aspects in more detail could allow the future use of this alternative material for routine toxicology analyzes in a forensic laboratory.


Assuntos
Líquido Cefalorraquidiano , Toxicologia Forense/métodos , Detecção do Abuso de Substâncias/métodos , Autopsia , Humanos
9.
Molecules ; 26(15)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34361564

RESUMO

Unintended pesticide pollution in soil, crops, and adjacent environments has caused several issues for both pesticide users and consumers. For users, pesticides utilized should provide higher yield and lower persistence while considering both the environment and agricultural products. Most people are concerned that agricultural products expose humans to pesticides accumulating in vegetation. Thus, many countries have guidelines for assessing and managing pesticide pollution, for farming in diverse environments, as all life forms in soil are untargeted to these pesticides. The stable isotope approach has been a useful technique to find the source of organic matter in studies relating to aquatic ecology and environmental sciences since the 1980s. In this study, we discuss commonly used analytical methods using liquid and gas chromatography coupled with isotopic ratio mass spectrometry, as well as the advanced compound-specific isotope analysis (CSIA). CSIA applications are discussed for tracing organic pollutants and understanding chemical reactions (mechanisms) in natural environments. It shows great applicability for the issues on unintended pesticide pollution in several environments with the progress history of isotope application in agricultural and environmental studies. We also suggest future study directions based on the forensic applications of stable isotope analysis to trace pesticides in the environment and crops.


Assuntos
Poluentes Ambientais/análise , Poluição Ambiental/análise , Toxicologia Forense , Resíduos de Praguicidas/análise , Isótopos/análise
10.
Molecules ; 26(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34361667

RESUMO

Examination of fentanyl levels is frequently performed in certain scientific evaluations and forensic toxicology. It often involves the collection of very variable blood samples, including lipemic plasma or serum. To date, many works have reported the methods for fentanyl detection, but none of them have provided information about the impact on the assay performance caused by an excessive amount of lipids. This aspect may be, however, very important for highly lipophilic drugs like fentanyl. To address this issue, we developed the liquid chromatography method with mass spectrometry detection and utilized it to investigate the impact of lipids presence in rabbit plasma on the analytical method performance and validation. The validation procedure, conducted for normal plasma and lipemic plasma separately, resulted in good selectivity, sensitivity and linearity. The limits of detection and quantification were comparable between the two matrices, being slightly lower in normal plasma (0.005 and 0.015 µg/L) than in lipemic plasma (0.008 and 0.020 µg/L). Liquid-liquid extraction provided a low matrix effect regardless of the lipid levels in the samples (<10%), but pronounced differences were found in the recovery and accuracy. In the normal plasma, this parameter was stable and high (around 100%), but in the lipemic matrix, much more variable and less efficient results were obtained. Nevertheless, this difference had no impact on repeatability and reproducibility. In the present work, we provided reliable, convenient and sensitive method for fentanyl detection in the normal and lipemic rabbit plasma. However, construction of two separate validation curves was necessary to provide adequate results since the liquid-liquid extraction was utilized. Therefore, special attention should be paid during fentanyl quantification that involves lipemic plasma samples purified by this technique.


Assuntos
Analgésicos Opioides/sangue , Fentanila/sangue , Toxicologia Forense/métodos , Hiperlipidemias , Extração Líquido-Líquido/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Coelhos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Artigo em Inglês | MEDLINE | ID: mdl-34333215

RESUMO

The past decades have seen a rise in the prescription of antipsychotic drugs in the European population, despite the risk of extra-pyramidal, metabolic and cardiac side effects. A multi-analyte liquid chromatography - triple quadrupole mass spectrometry method was developed for the quantification of 38 antipsychotic drugs in plasma. Samples were extracted by a straightforward liquid-liquid extraction with methyl-tertiary-butyl-ether and the compounds of interest were chromatographically separated within 6 min. Calibration curves covered the recommended therapeutic range for all compounds, in addition to sub- and supratherapeutic concentrations for most. The method was successfully validated according to the European Medicines Agency guidelines on bioanalytical method validation. Analysis of medico-legal samples confirmed the relatively common use of the second generation antipsychotics quetiapine and olanzapine, as well as the continued presence of the first generation antipsychotic haloperidol.


Assuntos
Antipsicóticos/sangue , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Antipsicóticos/química , Antipsicóticos/isolamento & purificação , Antipsicóticos/metabolismo , Monitoramento de Medicamentos , Toxicologia Forense , Humanos , Extração Líquido-Líquido , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
J Forensic Sci ; 66(6): 2104-2112, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34405898

RESUMO

Cannabis sativa L. is a substance widely used around the world for recreational and medicinal purposes. Oral fluid has been investigated as an alternative biological matrix for demonstrating the illegal use of cannabis, particularly in situations where its recent use needs to be identified. In the last two decades, many methods have been developed to detect and quantify cannabinoids in oral fluid, especially for Δ9 -tetrahydrocannabinol, the primary psychoactive substance of cannabis. However, some aspects must be considered in the use of these techniques, such as cannabinoids recoveries or extraction efficiency from different oral fluid collection devices/containers. Pharmacokinetic studies have shown that the presence of minor cannabinoids and metabolites in the analysis of oral fluid may be valuable in interpreting tests, which indicates the need to improve the sensitivity of detecting low concentrations. The aim of this review is to summarize and to describe the methodologies for the quantitative analysis of cannabinoids in oral fluid that have previously been investigated. A systematic search for articles was performed of four different databases, using the descriptor "cannabinoids and oral fluid". Forty-seven studies that examined quantitative methods were identified. The analytical data described in these articles, including oral fluid collection, sample preparation, cannabinoids recovery and extraction efficiency, detection instruments, and quantification limits, were analyzed. The discussion of these particular features of cannabinoid analysis in oral fluid could help to improve or to develop methods for use in Forensic Toxicology.


Assuntos
Canabinoides/análise , Saliva/química , Detecção do Abuso de Substâncias/métodos , Cromatografia Gasosa , Cromatografia Líquida , Toxicologia Forense/métodos , Humanos , Extração Líquido-Líquido , Espectrometria de Massas , Extração em Fase Sólida
13.
J Forensic Sci ; 66(6): 2532-2538, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34405913

RESUMO

Metomidate and etomidate belong to the non-barbiturate imidazole family of sedative-hypnotics and elicit little analgesic action when used alone. Metomidate, in particular, has little analgesic activity in humans and is, therefore, used for veterinary purposes. In 2019, a Korean woman in her twenties was found unconscious in a motel bath and eventually died. Etomidate, alprazolam, escitalopram, and metomidate were detected in the postmortem specimens. To our knowledge, this is the first case of human metomidate abuse reported in the Republic of Korea. In this research, a simple and reliable method was developed for the analysis of metomidate and etomidate in human blood samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Blood samples were deproteinized with acetonitrile, filtered, and analyzed by LC-MS/MS. Linear calibration curves were obtained with six concentrations ranging from 1 to 50 ng/ml for metomidate and 10 to 500 ng/ml for etomidate. The method was validated by assessing the selectivity, linearity, limit of detection (LOD), limit of quantitation (LOQ), intra- and inter-day precision and accuracy, matrix effect, and stability and successfully applied to the analysis of metomidate and etomidate in human blood samples. In a postmortem case, the concentrations of metomidate and etomidate were found to be 8 and 110 ng/ml in femoral blood and 6 and 210 ng/ml in cardiac blood, respectively.


Assuntos
Etomidato/análogos & derivados , Etomidato/sangue , Hipnóticos e Sedativos/sangue , Cromatografia Líquida , Etomidato/envenenamento , Feminino , Toxicologia Forense , Humanos , Hipnóticos e Sedativos/envenenamento , Transtornos Relacionados ao Uso de Substâncias , Espectrometria de Massas em Tandem , Adulto Jovem
14.
Molecules ; 26(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34443578

RESUMO

The misuse of fentanyl, and novel synthetic opioids (NSO) in general, has become a public health emergency, especially in the United States. The detection of NSO is often challenged by the limited diagnostic time frame allowed by urine sampling and the wide range of chemically modified analogues, continuously introduced to the recreational drug market. In this study, an untargeted metabolomics approach was developed to obtain a comprehensive "fingerprint" of any anomalous and specific metabolic pattern potentially related to fentanyl exposure. In recent years, in vitro models of drug metabolism have emerged as important tools to overcome the limited access to positive urine samples and uncertainties related to the substances actually taken, the possible combined drug intake, and the ingested dose. In this study, an in vivo experiment was designed by incubating HepG2 cell lines with either fentanyl or common drugs of abuse, creating a cohort of 96 samples. These samples, together with 81 urine samples including negative controls and positive samples obtained from recent users of either fentanyl or "traditional" drugs, were subjected to untargeted analysis using both UHPLC reverse phase and HILIC chromatography combined with QTOF mass spectrometry. Data independent acquisition was performed by SWATH in order to obtain a comprehensive profile of the urinary metabolome. After extensive processing, the resulting datasets were initially subjected to unsupervised exploration by principal component analysis (PCA), yielding clear separation of the fentanyl positive samples with respect to both controls and samples positive to other drugs. The urine datasets were then systematically investigated by supervised classification models based on soft independent modeling by class analogy (SIMCA) algorithms, with the end goal of identifying fentanyl users. A final single-class SIMCA model based on an RP dataset and five PCs yielded 96% sensitivity and 74% specificity. The distinguishable metabolic patterns produced by fentanyl in comparison to other opioids opens up new perspectives in the interpretation of the biological activity of fentanyl.


Assuntos
Fentanila/urina , Toxicologia Forense , Metabolômica , Urinálise/métodos , Cromatografia Líquida , Fentanila/metabolismo , Células Hep G2 , Humanos , Limite de Detecção
15.
J Forensic Sci ; 66(6): 2369-2380, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34459514

RESUMO

As seized drug casework becomes increasingly complex due to the continued prevalence of emerging drugs, laboratories are often looking for new analytical approaches including developing methods for the analysis of specific compounds classes. Recent efforts have focused on the development of targeted gas chromatography mass spectrometry (GC-MS) confirmation methods to compliment the information-rich screening results produced by techniques like direct analysis in real time mass spectrometry (DART-MS). In this work, a method for the confirmation of synthetic opioids and related compounds was developed and evaluated. An 11-component test solution was used to develop a method that focused on minimizing overlapping retention time acceptance windows and understanding the influence of instrument parameters on reproducibility and sensitivity. Investigated settings included column type, flow rate, temperature program, inlet temperature, source temperature, and tune type. Using a DB-200 column, a 35-min temperature ramped method was created. It was evaluated against a suite of 222 synthetic opioids and related compounds, and successfully differentiated all but four compound pairs based on nonoverlapping retention time acceptance windows or objectively different mass spectra. Compared to a general confirmatory method used in casework, the targeted method was up to 25 times more sensitive and provided at least a two-fold increase in retention time differences. Analysis of extracts from actual case samples successfully demonstrated utility of the method and showed no instance of carryover, although the high polarity column required wider retention time windows than other columns.


Assuntos
Analgésicos Opioides/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Medicamentos Sintéticos/química , Toxicologia Forense/métodos , Humanos , Reprodutibilidade dos Testes
16.
J Forensic Sci ; 66(6): 2156-2166, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34431514

RESUMO

Herbal blends containing synthetic cannabinoids have become popular alternatives to marijuana. The number of synthetic cannabinoids and speed of their emergence enable this group of compounds particularly challenging in terms of detection, monitoring, and responding. In this work, both gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR) methods were developed for the identification and quantification of synthetic cannabinoids in herbal blends. Ten types of indole/indazole carboxamide synthetic cannabinoids, which showed different types of substitutions connected to nitrogen of the indole/indazole carboxamide, were detected in 36 herbal blends. The GC-MS fragmentation routes of indole/indazole carboxamide synthetic cannabinoids were discussed in detail for structure identification purpose. The concentration range of synthetic cannabinoid in 36 herbal blends was 1.9-50.6 mg/g using GC-MS method, while 1.5-49.0 mg/g by NMR method. Nicotine in herbal blends was quantified by NMR method without using reference material, and showed a variation of 5.3-44.7 mg/g. For quantitative analysis, NMR method showed great advantage in the absence of reference material, while GC-MS method showed great merit for multiple-compound analysis when reference material was available. Therefore, for the quantitative analysis of new emerged synthetic cannabinoid in herbal blends, different methods could be chosen by considering whether reference material is available, as well as the number and types of synthetic cannabinoids detected in a single sample.


Assuntos
Canabinoides/química , Indazóis/análise , Indóis/análise , Preparações de Plantas/química , Medicamentos Sintéticos/química , Toxicologia Forense/métodos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Espectroscopia de Ressonância Magnética
17.
Forensic Sci Int ; 327: 110959, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34454378

RESUMO

Sharp force fatalities may have a homicidal, suicidal or accidental manner of death. To aid in such differentiation this study aimed to identify medico-legal elements which were predictors of a given manner of death as well as to describe the characteristics of these deaths. A retrospective review was performed on all homicides and suicides due to sharp force injury admitted at the South Branch of the National Institute of Legal Medicine and Forensic Sciences between January 2012 and December 2019. Deaths with a performed external examination or forensic autopsy and with available demographic, circumstantial or necroscopic information were included. Each case was reviewed to collect said information and inferential analysis was employed with both parametric and non-parametric tests as well as binary logistic regression to identify independent predictors, with significance defined at α = 0.05. A total of 57 homicides and 20 suicides were identified, with the obtained demographic and circumstantial profile of the homicide victim being that of a young foreign male whose body was found outside home, with no weapon nearby and without a known psychiatric background. Homicides presented more prominently stab wounds, with these being conspicuous on the thorax and neck. Conversely suicides notably presented cut wounds, being critically present in the neck and upper limbs. Oblique thoracic stab wounds conveyed a homicidal death. Other findings that suggested homicide included the presence of clothing damage, additional traumatic lesions and injured lungs or bone/cartilage. Toxicologically, alcohol presence was associated with homicides while psychiatric drugs suggested suicide. The logistic regression identified the presence of additional traumatic lesions (OR 14.8, p = 0.032) and the absence of lethal neck (OR 0.109, p = 0.043) and lethal upper limb (OR 0.022, p = 0.015) wounds as independent autopsy predictors of a homicidal death. However, no single feature is infallible in establishing manner of death. To achieve a cogent conclusion, all investigative elements must be considered while attending to the specifics of each case.


Assuntos
Homicídio , Suicídio , Ferimentos Penetrantes/epidemiologia , Adulto , Idoso , Autopsia , Causas de Morte , Feminino , Patologia Legal , Toxicologia Forense , Humanos , Masculino , Pessoa de Meia-Idade , Portugal/epidemiologia , Estudos Retrospectivos
18.
Forensic Sci Int ; 325: 110901, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34245938

RESUMO

Whole blood is most often the matrix of choice for postmortem analysis but it is not always available. In these cases, muscle tissue can be used as an alternative matrix. Therefore, an ultra-high-performance liquid chromatography-tandem mass spectrometry method for the quantification of 29 drugs and metabolites of toxicological interest in postmortem muscle tissue was developed and validated. Additionally, a validation of whole blood was carried out to compare the results from the two matrices. Solid-phase extraction was performed by an automated robotic system to minimize manual labour and risk of human errors, and increase robustness, sample throughput and sample traceability. The method was validated in terms of selectivity, matrix effect, extraction recovery, process efficiency, measuring range, lower limit of quantification, carry-over, stability, precision and accuracy. To correct for any inter-individual variability in matrix effects on analyte accuracy and precision, deuterated analogues of each analyte were used as internal standards. The lower limit of quantification in both blood and muscle homogenate ranged between 0.002 and 0.005 mg/kg, while the upper limit of quantification spanned from 0.20 to 1.0 mg/kg. Corrected with the 4-fold dilution factor, the corresponding concentrations in muscle tissue were 0.008-0.02 mg/kg at the lower limit of quantification and 0.80-4.0 mg/kg at the upper limit of quantification. The method showed acceptable precision and accuracy, with precision below 12% and accuracies ranging from 87% to 115% at up to 6 levels for all analytes in both matrices. In addition, comparison between calibration standards in spiked muscle homogenate and spiked blood showed that analyte concentrations in muscle samples could be quantified by using spiked blood samples as calibration standards with acceptable precision and accuracy when using deuterated analogues as internal standards. The investigation of matrix effects showed no great difference between blood and homogenates of non-decomposed and decomposed muscle tissue for most analytes. In the samples where high ion suppression or enhancement was observed, the results were corrected by the internal standards. Statistical comparison of quality control samples in blood and muscle tissue showed no obvious differences, and therefore muscle tissue was included in the routine method for analysis of blood samples and used in autopsy cases where no blood was available. By adding a semi-automated homogenization step before the remaining automated sample preparation, muscle tissue samples were easily incorporated into the workflow of the existing routine method. The present method has been successfully implemented in routine analysis of blood and muscle tissue since 2019.


Assuntos
Preparações Farmacêuticas/análise , Músculos Psoas/química , Automação Laboratorial , Cromatografia Líquida de Alta Pressão , Toxicologia Forense , Humanos , Robótica , Extração em Fase Sólida , Espectrometria de Massas em Tandem
19.
J Forensic Sci ; 66(6): 2484-2492, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34250598

RESUMO

Dual-column headspace gas chromatographic analysis with two flame-ionization detectors is a commonly used analytical technique for forensic blood ethanol quantitation. This technique is also applicable to the identification and quantitation of other volatile organic compounds such as methanol in biological samples. Compound identification by retention time is limited to those compounds with known retention times programmed into the instrument method. Historically, an early-eluting peak from an unidentified compound has been observed in both chromatograms from antemortem blood samples analyzed for ethanol concentration with this technique. The unidentified compound's retention time matches that of methanol on one column but not on the second column. This previously unidentified compound has been identified as isobutylene. The proposed source of the isobutylene contamination historically observed in antemortem blood samples collected in 10-ml gray-top blood collection tubes is the conventional rubber stopper. Isobutylene was detected in deionized water stored in each of the seven lots of 10-ml blood tubes tested; the expiration dates of the tubes tested spanned the years 2002-2022. Misidentification of isobutylene as methanol is possible when using a single-column gas chromatographic system. The presence of isobutylene in blood collected in a gray-top collection tube does not represent laboratory contamination, is not an interferent with blood ethanol quantitation, and does not affect the ethanol concentration in the blood. A 0.150 g/dl aqueous ethanol standard was stored in a gray-top tube to evaluate the potential impact of isobutylene on ethanol quantitation. The solution's average ethanol concentration measured after storage was 0.150 g/dl.


Assuntos
Alcenos , Coleta de Amostras Sanguíneas/instrumentação , Contaminação de Equipamentos , Depressores do Sistema Nervoso Central/sangue , Etanol/sangue , Toxicologia Forense , Humanos , Borracha
20.
J Forensic Sci ; 66(5): 1862-1870, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34302366

RESUMO

For years, a number of professional groups have warned forensic and clinical toxicologists against calculating an administered dose of a drug based on postmortem blood drug concentrations. But to date, there has been limited information as to how unreliable these dose calculations may actually be. Using amitriptyline as a model drug, this study used empirically determined pharmacokinetic variables for amitriptyline from clinical studies coupled with clinical overdoses (where the individual survived), and death case studies (ascribed to amitriptyline toxicity) in which the dose of amitriptyline was known. Using these data, standard pharmacokinetic equations, and general error propagation, it was possible to estimate the accuracy of calculated doses of amitriptyline, compared with the doses that were consumed. As was expected in postmortem cases, depending on the pharmacokinetic equation used, the accuracy (mean +128% to +2347%) and precision (SD ± 383% to 3698%) were too large to allow reliable estimations of the dose of amitriptyline consumed prior to death based on postmortem blood drug concentrations. This work again reinforces that dose calculations from postmortem blood drug concentrations are unreliable.


Assuntos
Cálculos da Dosagem de Medicamento , Toxicologia Forense , Farmacocinética , Mudanças Depois da Morte , Amitriptilina/sangue , Amitriptilina/farmacocinética , Humanos
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