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1.
Anal Bioanal Chem ; 406(14): 3497-506, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24682233

RESUMO

A multi-analyte method for the detection and quantification of 87 psychoactive drugs (antidepressants, antipsychotics, benzodiazepines, and z-drugs) in human hair has been developed and fully validated using the liquid chromatography-tandem mass spectrometry system. Due to the remarkable increase in requests of hair sample tests (such as for driver's license renewals, child custody, DFA cases, and postmortem toxicology), we focused on the development of a rapid sample preparation. About 20 mg of hair samples, previously washed and cut into snippets, was ultrasonicated with 700 µl of methanol. Samples were then directly analyzed using a 4000 QTRAP (AB SCIEX, Foster City, CA, USA) with an electrospray ionization (ESI) Turbo V(TM) Ion Source. The validation criteria parameters were satisfactory and in accordance with the international guidelines. All the compounds tested were successfully detected. One important aspect is the LODs in the low picogram per milligram concentration which may suggest a potential use of this method in cases of detection of single drug exposure. However, the LC-MS/MS method has been successfully applied for the analysis of postmortem cases (n = 9).


Assuntos
Cromatografia Líquida , Cabelo/química , Psicotrópicos/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Autopsia , Toxicologia Forense/métodos , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Detecção do Abuso de Substâncias/instrumentação , Detecção do Abuso de Substâncias/métodos , Tecnologia Farmacêutica
2.
Int J Digit Libr ; 22(4): 339-364, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34776774

RESUMO

Inferring the magnitude and occurrence of real-world events from natural language text is a crucial task in various domains. Particularly in the domain of public health, the state-of-the-art document and token centric event detection approaches have not kept the pace with the growing need for more robust event detection in public health. In this paper, we propose UPHED, a unified approach, which combines both the document and token centric event detection techniques in an unsupervised manner such that events which are: rare (aperiodic); reoccurring (periodic) can be detected using a generative model for the domain of public health. We evaluate the efficiency of our approach as well as its effectiveness for two real-world case studies with respect to the quality of document clusters. Our results show that we are able to achieve a precision of 60% and a recall of 71% analyzed using manually annotated real-world data. Finally, we also make a comparative analysis of our work with the well-established rule-based system of MedISys and find that UPHED can be used in a cooperative way with MedISys to not only detect similar anomalies, but can also deliver more information about the specific outbreak of reported diseases.

3.
Artigo em Inglês | MEDLINE | ID: mdl-26209771

RESUMO

The increasing number of new psychoactive substances (NPS) present in the illicit market render their identification in biological fluids/tissues of great concern for clinical and forensic toxicology. Analytical methods able to detect the huge number of substances that can be used are sought, considering also that many NPS are not detected by the standard immunoassays generally used for routine drug screening. The aim of this work was to develop a method for the screening of different classes of NPS (a total of 78 analytes including cathinones, synthetic cannabinoids, phenethylamines, piperazines, ketamine and analogues, benzofurans, tryptamines) from blood samples. The simultaneous extraction of analytes was performed by Dispersive Liquid/Liquid Microextraction DLLME, a very rapid, cheap and efficient extraction technique that employs microliters amounts of organic solvents. Analyses were performed by a target Ultrahigh Performance Liquid Chromatography tandem Mass Spectrometry (UHPLC-MS/MS) method in multiple reaction monitoring (MRM). The method allowed the detection of the studied analytes with limits of detection (LODs) ranging from 0.2 to 2ng/mL. The proposed DLLME method can be used as an alternative to classical liquid/liquid or solid-phase extraction techniques due to its rapidity, necessity to use only microliters amounts of organic solvents, cheapness, and to its ability to extract simultaneously a huge number of analytes also from different chemical classes. The method was then applied to 60 authentic real samples from forensic cases, demonstrating its suitability for the screening of a wide number of NPS.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Microextração em Fase Líquida/métodos , Psicotrópicos/sangue , Espectrometria de Massas em Tandem/métodos , Humanos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
4.
J Chromatogr A ; 1372C: 145-156, 2014 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-25465012

RESUMO

In the latest years, many new psychoactive substances (NPS) from several drug classes have appeared in the illicit drug market. Their rapid, sensitive and specific identification in biological fluids is hence of great concern for clinical and forensic toxicologists. Here is described a multi-analyte method for the determination of NPS, pertaining to different chemical classes (synthetic cannabinoids, synthetic cathinones, ketamine, piperazines and amphetamine-type substances-ATS) in human hair using ultrahigh performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) in electrospray ionization mode. We focused on a sample preparation able to extract the different classes of NPS. About 30mg of hair was decontaminated and incubated overnight under sonication in different conditions depending on the type of analytes to be extracted: (a) with 300µL of HCOOH 0.1% for cathinones, piperazines and ATS; (b) with 300µL of MeOH for synthetic cannabinoids. Ten microliter of the extracts were then injected in UHPLC-ESI-MS/MS in MRM mode. The LODs varied from 2pg/mg to 20pg/mg. The method was linear in the range from the LOQ to 500pg/mg and showed acceptable precision (%RSD<15) and accuracy (%E<15) for all the analytes. The method was finally applied on 50 samples from real forensic cases (driving license re-granting, postmortem toxicological analyses, workplace drug testing). In three samples we detected synthetic cannabinoids, in four samples cathinones or ephedrines, in two samples ketamine.

5.
J Forensic Leg Med ; 20(5): 555-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23756535

RESUMO

Tramadol is a synthetic opioid, widely used for post-surgical and chronic pain. Lethal overdose due only to tramadol is not common; more often the poisoning is due to tramadol in combination with other substances. Reported is a suicidal case of lethal tramadol poisoning in a 48-year-old woman. Tramadol and its metabolites O-desmethyltramadol (M1), N-desmethyltramadol (M2), N,N-didesmethyltramadol (M3), N,O-didesmethyltramadol (M5) were detected by GC/MS in biological fluids (femoral blood, bile, urine, gastric content) and viscera (brain, lung, liver and kidney). The tramadol concentration in femoral blood was 61.83 mcg/ml which is approximately 30 times higher than that believed to be lethal. According with other Authors, a preferential formation of M1 over M2 (M1/M2 ratio >1) is indicative of acute death, while M1/M2 ratio <1 suggests that death occurred after a longer time lapse from ingestion.


Assuntos
Analgésicos Opioides/intoxicação , Suicídio , Tramadol/intoxicação , Analgésicos Opioides/análise , Bile/química , Feminino , Toxicologia Forense , Cromatografia Gasosa-Espectrometria de Massas , Conteúdo Gastrointestinal/química , Humanos , Pessoa de Meia-Idade , Tramadol/análogos & derivados , Tramadol/análise
6.
Ital J Anat Embryol ; 116(1): 30-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21898971

RESUMO

As it is well known, bone tissue is characterized by a calcified extracellular matrix which makes this tissue suitable to support the body and protect the inner organs. Lamellar bone tissue is organized in lamellae, 3-7 microm in thickness, and arranged concentrically around vascular channels: the basic structure in this type of organization is called Haversian system or osteon and the diameter of osteons depends on the number of lamellae. Shape and regional density of osteons are related to the bone segment and the specific functional requirements to meet. Aim of this study is to correlate the compact bone tissue microstructure in various classes of mammals, including humans, and birds in order to find an adequate identification key. The results of our study show that in bone tissue samples from various classes of mammals, including humans, and birds the osteonic structure shows peculiar features, often depending on the rate of bone remodelling, different in different animal species. We conclude that a careful microscopic analysis of bone tissue and the characterization of distinctive osteonic features could give a major contribution to forensic medicine to obtain a more reliable recognition of bone findings.


Assuntos
Extremidades/anatomia & histologia , Fêmur/citologia , Ósteon/citologia , Animais , Bovinos , Galinhas , Extremidades/fisiologia , Fêmur/irrigação sanguínea , Fêmur/fisiologia , Ósteon/fisiologia , Humanos , Microcirculação/fisiologia , Projetos Piloto , Roedores , Carneiro Doméstico , Sus scrofa
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