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1.
Electrophoresis ; 44(5-6): 521-528, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36640222

RESUMO

Statins are cholesterol-lowering medications which are widely prescribed as first-line treatment for hyperlipidemia, against high blood cholesterol aimed at reducing the risk of atherosclerotic diseases. Notwithstanding their undoubted efficacy, the needed long-term treatment with these drugs is characterized by a high percentage of dropout. Consequently, an effective tool to verify the patients' compliance to statin therapy is needed. In this context, the analysis for drugs and drug metabolites in the hair may represent an almost ideal tool because, according to a sound body of forensic toxicological literature, concentrations in the hair matrix reflect the chronic intake of drugs and pharmaceuticals. In this light, in the present study, a novel, specific and sensitive ultra-performance liquid chromatography-tandem mass spectrometry method has been developed to determine six statins and their metabolites (namely atorvastatin, (p)α-OH-atorvastatin-lactone, (o)α-OH-atorvastatin-lactone, rosuvastatin, N-desmethyl rosuvastatin and pravastatin) in human hair. After optimization, the method was successfully validated in terms of selectivity, linearity, sensitivity, precision, accuracy, stability and matrix effect. Moreover, the practical applicability of this method for verifying adherence to statin therapy was assessed by testing samples of hair collected from subjects under long-term therapy with statins.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Atorvastatina/uso terapêutico , Análise do Cabelo , Pravastatina/uso terapêutico , Colesterol
2.
Int J Legal Med ; 137(3): 887-895, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36799966

RESUMO

INTRODUCTION: The estimation of post-mortem interval (PMI) remains a major challenge in forensic science. Most of the proposed approaches lack the reliability required to meet the rigorous forensic standards. OBJECTIVES: We applied 1H NMR metabolomics to estimate PMI on ovine vitreous humour comparing the results with the actual scientific gold standard, namely vitreous potassium concentrations. METHODS: Vitreous humour samples were collected in a time frame ranging from 6 to 86 h after death. Experiments were performed by using 1H NMR metabolomics and ion capillary analysis. Data were submitted to multivariate statistical data analysis. RESULTS: A multivariate calibration model was built to estimate PMI based on 47 vitreous humour samples. The model was validated with an independent test set of 24 samples, obtaining a prediction error on the entire range of 6.9 h for PMI < 24 h, 7.4 h for PMI between 24 and 48 h, and 10.3 h for PMI > 48 h. Time-related modifications of the 1H NMR vitreous metabolomic profile could predict PMI better than potassium up to 48 h after death, whilst a combination of the two is better than the single approach for higher PMI estimation. CONCLUSION: The present study, although in a proof-of-concept animal model, shows that vitreous metabolomics can be a powerful tool to predict PMI providing a more accurate estimation compared to the widely studied approach based on vitreous potassium concentrations.


Assuntos
Mudanças Depois da Morte , Potássio , Ovinos , Animais , Potássio/análise , Corpo Vítreo/química , Reprodutibilidade dos Testes , Metabolômica
3.
J Antimicrob Chemother ; 77(3): 747-752, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-34849955

RESUMO

BACKGROUND: Short-cycle therapy (SCT) is the administration of ART for 4 or 5 consecutive days a week, followed by 3 or 2 days off therapy. Its benefits include improving patient satisfaction and reducing ART toxicity and costs. METHODS: In this observational study we included HIV-infected adults with a three-drug ART containing rilpivirine, a history of long-term virological suppression and no evidence of resistance to previous drug regimens. Patients switched to a SCT of 4 days on/3 days off and were followed for 48 weeks with regular check-ups. The primary outcome was virological suppression; secondary outcomes were changes in CD4+ cells and rilpivirine plasma concentration, the occurrence of adverse events and resistance in the case of failure, and patient satisfaction. RESULTS: At week 48 no virological failure was observed, with a virological suppression rate of 30/30 (100%). Three patients switched back to continuous therapy for other reasons, with an overall success rate of SCT of 30/33 (90.9%, 95% CI = 81.24% to 100%). The CD4+ mean value increased by +64 cells/mm3 (95% CI = -59 to +187 cells/mm3; P = 0.052). No adverse events were observed and the mean total score in the satisfaction questionnaire was 57.7/60 (96.22%). Rilpivirine plasma concentration was below the efficacy threshold in 71.3% of the samples, suggesting that the patients' characteristics, more than the drug's pharmacokinetics, played a role in maintaining virological suppression. CONCLUSIONS: SCT with rilpivirine-containing regimens could be an effective alternative to continuous therapy in selected HIV-infected patients with previous long-term virological suppression.


Assuntos
Infecções por HIV , HIV-1 , Infecções por HIV/tratamento farmacológico , Humanos , Rilpivirina/efeitos adversos
4.
Electrophoresis ; 43(9-10): 1019-1026, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35132652

RESUMO

Cardiac glycosides digoxin and digitoxin are used in therapy for the treatment of congestive heart failure. Moreover, these compounds can be responsible for intoxication cases caused by fortuitous ingestion of leaves of Digitalis. Due to the narrow therapeutic range of these drugs, therapeutic drug monitoring is recommended in the clinical practice. In this context, immunoassays-based methods are generally employed but digoxin- and digitoxin-like compounds can interfere with the analysis. The aim of this study was to develop and validate an original UPLC-MS/MS method for the determination of digoxin and digitoxin in plasma. The method shows adequate sensitivity and selectivity with acceptable matrix effects and very good linearity, accuracy, precision, and recovery. A simple liquid-liquid extraction procedure was used for sample clean-up. The method was applied for the analysis of n = 220 plasma samples collected in two different clinical chemistry laboratories and previously tested by the same immunoassay. The statistical comparison showed a relevant negative bias of the UPLC-MS/MS method versus the immunoassay. These results are consistent with an immunoassay overestimation of digoxin plasmatic levels due to cross-reaction events with endogenous digoxin-like substances.


Assuntos
Digitoxina , Digoxina , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Digitoxina/química , Digoxina/química , Imunoensaio , Espectrometria de Massas em Tandem/métodos
5.
Electrophoresis ; 42(4): 450-459, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33263181

RESUMO

The continuous introduction in the market of new psychoactive drugs (NPS) represents a well-known international emergency. Indeed, the European Monitoring Centre for Drugs and Drug Addiction and the United Nations Office on Drugs and Crime are paying great attention to the spread of NPS. In addition to the traditional analytical approaches based on GC-MS and HPLC-MS, also CE coupled with MS has proved to be a precious tool for the toxicological screening of biosamples. On these grounds, the aim of the present work was to test the application of CE-HRMS as a new screening tool for the rapid detection of these novel drugs in urine. Separations were performed in an uncoated fused-silica capillary with id of 75 µm with a total length of 100 cm, by applying a constant voltage of 15 kV. The QTOF-MS was implemented with an electrospray ion source operating in positive ionization full scan mode in the range of 100-1000 m/z. Under these conditions, different NPS has been tested, including eight cathinones, five phenethylamine, and seven tryptamines. The method was validated after optimization of the following analytical parameters: BGE composition and pH, separation voltage, sheath liquid composition, and flow rate and ESI source settings. The applicability of the method was successfully tested by analyzing a series of real urine samples obtained from drug users.


Assuntos
Alcaloides/urina , Aminas/urina , Eletroforese Capilar/métodos , Espectrometria de Massas/métodos , Psicotrópicos/urina , Humanos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Detecção do Abuso de Substâncias
6.
Int J Legal Med ; 135(3): 845-852, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33219398

RESUMO

Estimation of the post-mortem interval (PMI) remains a matter of concern in the forensic scenario. Traditional and novel approaches are not yet able to fully address this issue, which relies on complex biological phenomena triggered by death. For this purpose, eye compartments may be chosen for experimental studies because they are more resistant to post-mortem modifications. Vitreous humour, in particular, has been extensively investigated, with potassium concentration ([K+]) being the marker that is better correlated with PMI estimation. Recently, a 1H nuclear magnetic resonance (NMR) metabolomic approach based on aqueous humour (AH) from an animal model was proposed for PMI estimation, resulting in a robust and validated regression model. Here we studied the variation in [K+] in the same experimental setup. [K+] was determined through capillary ion analysis (CIA) and a regression analysis was performed. Moreover, it was investigated whether the PMI information related to potassium could improve the metabolome predictive power in estimating the PMI. Interestingly, we found that a part of the metabolomic profile is able to explain most of the information carried by potassium, suggesting that the rise in both potassium and metabolite concentrations relies on a similar biological mechanism. In the first 24-h PMI window, the AH metabolomic profile shows greater predictive power than [K+] behaviour, suggesting its potential use as an additional tool for estimating the time since death.


Assuntos
Humor Aquoso/química , Metabolômica , Mudanças Depois da Morte , Potássio/análise , Animais , Modelos Animais de Doenças , Eletroforese Capilar , Espectroscopia de Prótons por Ressonância Magnética , Análise de Regressão , Ovinos
7.
Clin Chem Lab Med ; 57(4): 504-509, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30157025

RESUMO

Background Although the post-mortem increase of ammonium in biological fluids is well known, ammonium analysis in vitreous humour has never been used in recent times for the determination of the post-mortem interval. The present work represents a new application of capillary electrophoresis with indirect UV detection in the field of forensic analysis. Methods The electrophoretic separation was carried out in a running buffer made of 5 mM imidazole, 5 mM 18-crown-6 ether and 6 mM d,l-α-hydroxybutyric acid (HIBA). To overcome the lack of optical absorption of ammonium, indirect UV detection was applied. The used wavelength was 214 nm. Results The method showed good linearity in the concentration range from 0.16 to 5.0 mM. The limit of detection, 0.039 mmol/L, was established on the basis of the linearity curve. Precision and bias studies carried out on the pure ammonium solutions and in real biological samples, revealed %RSDs well below 20%. A preliminary application to real cases where the death time was precisely known (14 bodies) was carried out plotting vitreous humour ammonium vs. post-mortem interval with a resulting good linear correlation until 100 h post-mortem. Conclusions After validation in real cases, the present method can become a powerful tool to unravel one of the most challenging issues of forensic investigation: determination of the time of death.


Assuntos
Compostos de Amônio/análise , Eletroforese Capilar/métodos , Medicina Legal , Espectrofotometria Ultravioleta/métodos , Corpo Vítreo/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Ig Sanita Pubbl ; 75(5): 377-384, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31971522

RESUMO

OBJECTIVE: The study compare two tests for evaluating the driving abilities of patients undergoing opioid therapy for chronic pain: the Vienna Test System (VTS), a software developed for this purpose, and a new free APP for smartphones (SafeDrive) measuring visual and auditory reaction times. METHODS: One hundred and five patients undergoing long term opioid therapy for chronic pain were enrolled. The driving abilities of study patients were evaluated using two tests, namely the Vienna test System (VTS) and the SafeDrive APP. The concordance between the two tests was evaluated through Cohen's test. In addition we evaluated the correlation between the results of both VTS and SafeDrive tests and prescribed Morphine Equivalent Doses (MEDs), sex, age and the specific drugs taken, by multivariate linear regression analysis. RESULTS: A statistically significant concordance (Cohen's K coefficient=0.476) was found between the SafeDrive APP and the VTS; multivariate linear regression analysis found no significant influences of dosage and type of opioid prescribed on test performances, but significant influences of sex and age. CONCLUSIONS: The Authors found a significant correlation between VTS with SafeDrive test results. The SafeDrive APP is cheaper, easier to use and faster than VTS, and is portable and "usable on the road". Complex behavioral tasks such as driving may be severely impaired by psychoactive drugs, and consequently SafeDrive could be considered a useful portable screening tool to identify drivers with drug associated psychomotor impairment.


Assuntos
Analgésicos Opioides/uso terapêutico , Condução de Veículo , Dor Crônica/tratamento farmacológico , Destreza Motora/efeitos dos fármacos , Humanos , Smartphone
9.
Eur J Clin Invest ; 48(2): e12870, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29235098

RESUMO

BACKGROUND: The liver hormone hepcidin regulates iron homoeostasis that is often altered in hepatocellular carcinoma (HCC). Epigenetic phenomena control gene expression through a dynamic fashion; therefore, considering the plasticity of both iron homoeostasis and epigenetic mechanisms and their role in liver carcinogenesis, we investigated whether hepcidin gene (HAMP) expression is modulated by DNA methylation, thus affecting iron status in human HCC. MATERIALS AND METHODS: Thirty-two patients affected by nonviral HCC were enrolled, and their main clinical and biochemical characteristics were obtained. Neoplastic and homologous non-neoplastic liver tissues were analysed for HAMP promoter DNA methylation, for HAMP gene expression and for iron content. An in vitro demethylation assay with a human hepatocarcinoma cell line was performed to evaluate the role of DNA methylation on HAMP transcriptional repression. RESULTS: Gene expression and DNA methylation analyses on tissues showed that HAMP was transcriptionally repressed in HCC tissues consensually with a promoter hypermethylation. Furthermore, patients with HCC had low serum hepcidin concentrations, and HCC tissues had relative iron depletion as compared to non-neoplastic liver tissues. The cell culture model showed the functional role of DNA hypermethylation by downregulating HAMP gene expression. Through a quantitative methylation analysis on HCC tissues, we then proved that methylation at definite CpG sites within consensus sequences for specific transcription factors is possibly the mechanism underlying HAMP repression. CONCLUSIONS: This study highlights a novel role for HAMP downregulation through DNA promoter hypermethylation and emphasises the significance of epigenetics in the regulation of iron metabolism in HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Metilação de DNA/fisiologia , Hepcidinas/metabolismo , Neoplasias Hepáticas/metabolismo , Regiões Promotoras Genéticas/fisiologia , Idoso , Análise de Variância , Proteínas de Transporte de Cátions/metabolismo , Regulação para Baixo/fisiologia , Feminino , Expressão Gênica/fisiologia , Hepcidinas/genética , Humanos , Deficiências de Ferro , Masculino , Proteínas de Membrana/metabolismo , Serina Endopeptidases/metabolismo , Transcrição Gênica/fisiologia
10.
Med Sci Law ; 54(1): 22-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23842479

RESUMO

The current analytical technology for the determination of New Psychoactive Substances in biological samples is still largely inadequate, because the immunoassays are unsuitable for the detection of most of these compounds and the use of traditional gas chromatography-mass spectrometry techniques is hampered by the lack of chromatographic standards and mass fragmentation patterns. Taking advantage of the molecular recognition capability of high-resolution mass spectrometry, the present work aimed to apply liquid chromatography-quadrupole-time of flight mass spectrometry for the rapid identification of New Psychoactive Substances in the hair, a peculiar tissue which "keeps memory" of the recent history of drug intake of the subject. All the samples were screened for the presence of 50 different New Psychoactive Substances (synthetic cannabinoids, cathinones and phenethylamines), substances that had been reported officially by the National Early Warning System in the period 2009-2011. Among the 435 samples analyzed, 8 were found "positive" for the following compounds: JWH-018, JWH-073, JWH-081, JWH-250, JWH-122, in a broad range of concentrations (0.010-1.28 ng/mg). Results strongly support the use of hair analysis to monitor the diffusion of new psychoactive drugs in the community.


Assuntos
Canabinoides/análise , Cabelo/química , Detecção do Abuso de Substâncias/métodos , Cromatografia Líquida , Humanos , Espectrometria de Massas/métodos
11.
Leg Med (Tokyo) ; 67: 102375, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38154312

RESUMO

INTRODUCTION: Carbon monoxide (CO) poisoning is a significant concern in forensic medicine, as it often presents unique challenges in terms of diagnosis, investigation, and determination of the cause of death. CO is a colourless, odourless, and tasteless gas that can be lethal when inhaled in high concentrations. It binds strongly to haemoglobin, forming carboxyhaemoglobin (COHb), which reduces the oxygen-carrying capacity of the blood, leading to tissue hypoxia and ultimately death. MATERIALS AND METHODS: Circumstantial data, medical history information, autopsy findings, and toxicological analysis results related to 24 CO poisoning cases at the Institute of Legal Medicine in Verona were collected and analysed. The data were examined in an integrated manner to identify correlations and common patterns. A comparison was also made with the data available in the literature. RESULTS: The male gender was confirmed to be the most frequently involved. COHb levels were found to be less than 50% in 6 cases. Three individuals had concurrent cardiovascular pathologies, while 11 subjects tested positive for various substances, including alcohol, benzodiazepines, and morphine. In most cases, the manner of fatal intoxication was accidental, although 6 suicides and 1 homicide are reported. CONCLUSIONS: The Verona case series demonstrates that deaths due to CO poisoning require a multidisciplinary approach. The integration of diverse expertise is essential for assessing the manner of death. This approach enables a comprehensive evaluation of the available data, aids in distinguishing between accidental, suicidal, and homicidal deaths, and ensures accurate and reliable forensic conclusions.


Assuntos
Intoxicação por Monóxido de Carbono , Suicídio , Humanos , Masculino , Monóxido de Carbono , Acidentes , Homicídio , Intoxicação por Monóxido de Carbono/diagnóstico , Intoxicação por Monóxido de Carbono/patologia
12.
Drug Test Anal ; 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37916273

RESUMO

The use of novel psychoactive substances (NPSs) has dramatically increased worldwide, and among them, synthetic opioids are one of the fastest growing groups, where cinnamylpiperazines and 2-benzylbenzimidazoles represent two of the most relevant subclasses. However, the data on their toxicity and metabolism are still limited. The aim of the present study was to evaluate the toxicity and metabolic pathways of some compounds belonging to these families, namely, AP-237, 2-methyl AP-237, isotonitazene, flunitazene, etodesnitazene, metonitazene, metodesnitazene, N-pyrrolidino etonitazene, and butonitazene. The study was performed using a zebrafish early life stages model. In fact, zebrafish (Danio rerio) embryos and larvae have recently been recognized as a suitable animal model in alternative to mammals, because they require less time and resources and do not need complex procedures for ethics approval. The cellular toxicity after a single administration was assessed at the fourth day post-fertilization with acridine orange staining. Possible morphological defects were evaluated with a light microscope after 24 h of exposure to 1 µmol/L concentration of each drug. Subsequently, the larvae were euthanized and underwent analysis of drug metabolites using UPLC coupled to an Orbitrap high-resolution mass spectrometer. High rates of morphological defects, as well as of cellular death, were detected, but no significant difference in mortality between treatment and control groups was observed. In addition, several metabolites, mainly produced through monohydroxylation, N-dealkylation, and O-dealkylation, were identified in the larvae extracts.

13.
Drug Test Anal ; 15(9): 980-986, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37154073

RESUMO

The work discusses the results of hair and urine testing performed in 51 cases of suspected in utero drug exposure handled at the University Hospital of Verona from 2016 to 2022. On the day of birth or the day after birth, urine from mother and newborn (UM and UN) and hair from mother (HM), newborn (HN) and father (HF), if possible, were collected. Urine underwent immunoassay and GC-MS analysis, whereas hair underwent LC-MS/MS and GC-MS/MS analysis. In 50 out of 51 cases, HM and/or HN were available. In 92% of them, hair testing resulted in a positive, often (>50% cases) for more than one class of substance. The most detected substances were cocaine, opiates, methadone and cannabinoids. Maternal segmental analysis showed a prevalent decreasing concentration trend during pregnancy in case of positivity for one class of substances, whereas, as expected, a neatly prevalent increasing trend in the case of positivity for more than one class of substances. In nine cases, HF was also available, resulting in all being positive, usually for the same classes of substances identified in HM, thus questioning parental responsibility. In 33 cases, urine samples from the mother or newborn were also collected. Of them, 27 cases (82%) tested positive, showing peri-partum drug consumption and then confirming the severity of the addiction. Hair testing showed to be a reliable diagnostic tool to investigate in utero drug exposure because of the possibility of obtaining a complete picture of maternal addictive behaviour and family background, thanks to segmental maternal hair analysis and father hair testing.


Assuntos
Cocaína , Transtornos Relacionados ao Uso de Substâncias , Gravidez , Recém-Nascido , Feminino , Humanos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida , Cocaína/análise , Cabelo/química , Hospitais , Detecção do Abuso de Substâncias/métodos
14.
Electrophoresis ; 33(4): 599-606, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22451052

RESUMO

The present work is aimed at investigating the influence of the background electrolyte composition and concentration on the separation efficiency and resolution and mass spectrometric detection of illicit drugs in a capillary zone electrophoresis-electrospray ionization-time of flight mass spectrometry (CZE-ESI-TOF MS) system. The effect of phosphate, borate and Tris buffers on the separation and mass spectrometry response of a mixture of 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, methadone, cocaine, morphine, codeine and 6-monoacetylmorphine was studied, in comparison with a reference ammonium formate separation buffer. Inorganic non-volatile borate and Tris buffers proved hardly suitable for capillary electrophoresis-mass spectrometry (CE-MS) analysis, but quite unexpectedly ammonium phosphate buffers showed good separation and ionization performances for all the analytes tested. Applications of this method to real samples of hair from drug addicts are also provided.


Assuntos
Eletroforese Capilar/métodos , Toxicologia Forense/métodos , Drogas Ilícitas/análise , Espectrometria de Massas/métodos , Soluções Tampão , Cabelo/química , Humanos , Fosfatos/química
15.
Drug Test Anal ; 14(10): 1773-1778, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35855505

RESUMO

Adherence to therapy is the key to a successful therapeutic intervention, especially in cardiovascular diseases in which a lack of adherence may have serious consequences in terms morbidity and/or mortality. In this context, hair analysis can be an excellent tool to monitor adherence to therapy. Indeed, drugs present in blood are incorporated into the hair matrix, where drugs and metabolites can stay unaltered for a long time protected from metabolism and degradation. In the present study, a simple, specific, and sensitive ultra-high performance liquid-chromatography-tandem mass spectrometry (UHPLC-MS/MS) method set up to determine in human hair seven beta-blockers (viz., metoprolol, sotalol, labetalol, atenolol, nebivolol, bisoprolol, and nadolol) and two calcium-channel blockers (lercanidipine and amlodipine), which are widely prescribed to treat medium-to-severe hypertensive conditions. The optimized method was successfully validated in terms of accuracy, repeatability, reproducibility, matrix effect and extraction recovery. Moreover, the applicability of the method was evaluated by analyzing 34 real samples of hair obtained from patients under long-term therapy with calcium channel blockers and beta-blockers.


Assuntos
Labetalol , Espectrometria de Massas em Tandem , Antagonistas Adrenérgicos beta/uso terapêutico , Anlodipino , Anti-Hipertensivos/uso terapêutico , Atenolol , Bisoprolol/uso terapêutico , Cálcio , Bloqueadores dos Canais de Cálcio/uso terapêutico , Cromatografia Líquida/métodos , Análise do Cabelo , Humanos , Metoprolol , Nadolol , Nebivolol , Reprodutibilidade dos Testes , Sotalol , Espectrometria de Massas em Tandem/métodos
16.
J Pharm Anal ; 11(3): 292-298, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34277117

RESUMO

In the present work, dispersive liquid-liquid microextraction (DLLME) was used to extract six synthetic cannabinoids (JWH-018, JWH-019, JWH-073, JWH-200, or WIN 55,225, JWH-250, and AM-694) from oral fluids. A rapid baseline separation of the analytes was achieved on a bidentate octadecyl silica hydride phase (Cogent Bidentate C18; 4.6 mm × 250 mm, 4 µm) maintained at 37 °C, by eluting in isocratic conditions (water:acetonitrile (25:75, V/V)). Detection was performed using positive electrospray ionization-tandem mass spectrometry. The parameters affecting DLLME (pH and ionic strength of the aqueous phase, type and volume of the extractant and dispersive solvent, vortex and centrifugation time) were optimized for maximizing yields. In particular, using 0.5 mL of oral fluid, acetonitrile (1 mL), was identified as the best option, both as a solvent to precipitate proteins and as a dispersing solvent in the DLLME procedure. To select an extraction solvent, a low transition temperature mixture (LTTM; composed of sesamol and chlorine chloride with a molar ratio of 1:3) and dichloromethane were compared; the latter (100 µL) was proved to be a better extractant, with recoveries ranging from 73% to 101 % by vortexing for 2 min. The method was validated according to the guidelines of Food and Drug Administration bioanalytical methods: intra-day and inter-day precisions ranged between 4 % and 18 % depending on the spike level and analyte; limits of detection spanned from 2 to 18 ng/mL; matrix-matched calibration curves were characterized by determination coefficients greater than 0.9914. Finally, the extraction procedure was compared with previous methods and with innovative techniques, presenting superior reliability, rapidity, simplicity, inexpensiveness, and efficiency.

17.
Forensic Sci Int ; 325: 110855, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34098473

RESUMO

In recent years, a significant increase of reports about suicidal cases due to intentional sodium nitrite intake has been described. In the forensic pathology context, the strategy to approach intoxication cases by sodium nitrite, without any preliminary information or hint, is not straightforward. Indeed, in a number of cases the lack of crime scene data and/or specific pathological signs makes difficult the identification of nitrite poisoning. Moreover, the analytical determination of nitrite in blood is challenging, due to its rapid oxidization to nitrate by hemoglobin. Although several methods have been proposed for the clinical analysis of nitrate and/or nitrite in biological samples, none of these is specifically focused on the determination of these ions in cadaveric samples. Consequently, the diagnosis of nitrite fatal intoxication is still based on methemoglobin analysis. The present paper reports the optimization and validation of an analytical method of capillary ion analysis (CIA) with UV detection, for the determination of nitrite and nitrate in biological fluids and its application to two authentic cases of death by nitrite intake. The analyses were carried out in a bare fused-silica capillary (75 µm inner diameter) using 100 mM sodium tetraborate (pH 9.24) as background electrolyte and applying a voltage of - 15 kV between the capillary ends. The detection was obtained by direct UV absorption recorded at 214 nm wavelength. Bromide was used as the internal standard. Linearity was established in the range of 0.25-5 mmol/L). Reproducibility (intraday and day-to-day) was characterized by relative standard deviations (RSDs) 14.7% for peak areas. The method was applied to the determination of nitrite and nitrate in two real forensic cases, where high concentrations of nitrate were found in cadaveric blood samples (6.5 and 4.4 mmol/L, respectively). Nitrite was found only in trace amounts, due to the instability of this ion in cadaveric blood where it is oxidized to nitrate. The present method represents a new tool for the direct and rapid determination of nitrite and nitrate in cases of forensic interest, and thus offers a diagnostic tool more sensitive and precise than the need methemoglobin analysis.


Assuntos
Eletroforese Capilar/métodos , Nitratos/sangue , Nitrito de Sódio/intoxicação , Adulto , Toxicologia Forense/métodos , Humanos , Masculino , Intoxicação/diagnóstico , Reprodutibilidade dos Testes , Raios Ultravioleta
18.
Front Psychiatry ; 12: 646038, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33815177

RESUMO

An effective approach in the treatment of benzodiazepine (BZD) overdosing and detoxification is flumazenil (FLU). Studies in chronic users who discontinued BZD in a clinical setting suggested that multiple slow bolus infusions of FLU reduce BZD withdrawal symptoms. The aim of this study was to confirm FLU efficacy for reducing BZD withdrawal syndrome by means of continuous elastomeric infusion, correlated to drugs plasma level and patients' compliance. Methods: Seven-day FLU 1 mg/day subcutaneously injected through an elastomeric pump and BZDs lormetazepam, clonazepam, and lorazepam were assessed by HPLC-MS/MS in serum of patients before and after 4 and 7 days of FLU continuous infusion treatment. Changes in withdrawal severity were assessed by using the BZD Withdrawal Scale (BWS). Results: Fourteen patients (mean age ± SD 42.5 ± 8.0 years, 5 male and 9 female), admitted to the hospital for high-dose BZD detoxification, were enrolled in the study. Serum FLU concentrations significantly decreased from 0.54 ± 0.33 ng/ml (mean ± SD) after 4 days of treatment to 0.1 ± 0.2 ng/ml at the end of infusion. Lormetazepam concentrations were 502.5 ± 610.0 ng/ml at hospital admission, 26.2 ± 26.8 ng/ml after 4 days, and 0 at the end of treatment. BWS values decreased during FLU treatment temporal period. FLU was well-tolerated by patients. Conclusions: Elastomeric FLU infusion for BZD detoxification is a feasible administration device to maintain adequate, constant, and tolerated FLU concentrations for reducing BZD withdrawal symptoms.

19.
Med Sci Law ; 61(1_suppl): 96-104, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32588729

RESUMO

Post-mortem changes of ions in the body fluids have been proposed as an objective tool for inferring the time of death. In particular, the post-mortem increase of potassium concentrations in the vitreous humour has gained great attention in the literature. On the other hand, ammonium, another ion released in post-mortem processes, has received much less attention, potentially due to unresolved analytical issues using current clinical chemistry methods. This paper presents an application of a new analytical approach based on capillary electrophoresis providing the simultaneous analysis of potassium and ammonium ions in the vitreous humour. In addition, to assess the consistency of the post-mortem increase of ammonium concentrations in the vitreous humour, the determination of this ion in the vitreous humour of the two eyes of the same body at the same post-mortem interval has been verified. Vitreous humour was collected from 33 medico-legal cases where the time of death was known exactly. Prior to analysis, all samples were diluted 1:20 with a 40 µg/mL solution of BaCl2 (internal standard). In the study of the variability of the ammonium concentration between the two eyes, no statistically significant differences were found, supporting the hypothesis of an even post-mortem increase of the ion concentrations in this particular biological fluid. Significant correlations of potassium and ammonium ions with the post-mortem interval were found, with r2 of 0.75 and 0.70, respectively.


Assuntos
Compostos de Amônio/análise , Eletroforese Capilar , Mudanças Depois da Morte , Potássio/análise , Corpo Vítreo/química , Humanos
20.
Electrophoresis ; 31(7): 1256-1263, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20209571

RESUMO

This article describes a method for the separation and determination of nine drugs of abuse in human urine, including amphetamines, cocaine, codeine, heroin and morphine. This method was based on SPE on a strong cation exchange cartridge followed by CEC-MS. The CEC experiments were performed in fused silica capillaries (100 microm x 30 cm) packed with a 3 mum cyano derivatized silica stationary phase. A laboratory-made liquid junction interface was used for CEC-MS coupling. The outlet capillary column was connected with an emitter tip that was positioned in front of the MS orifice. A stable electrospray was produced at nanoliter per minute flow rates applying a hydrostatic pressure (few kPa) to the interface. The coupling of packed CEC columns with mass spectrometer as detector, using a liquid junction interface, provided several advantages such as better sensitivity, low dead volume and independent control of the conditions used for CEC separation and ESI analysis. For this purpose, preliminary experiments were carried out in CEC-UV to optimize the proper mobile phase for CEC analysis. Good separation efficiency was achieved for almost all compounds, using a mixture containing ACN and 25 mM ammonium formate buffer at pH 3 (30:70, v/v), as mobile phase and applying a voltage of 12 kV. ESI ion-trap MS detection was performed in the positive ionization mode. A spray liquid, composed by methanol-water (80:20, v/v) and 1% formic acid, was delivered at a nano-flow rate of approximately 200 nL/min. Under optimized CEC-ESI-MS conditions, separation of the investigated drugs was performed within 13 min. CEC-MS and CEC-MS(2) spectra were obtained by providing the unambiguous confirmation of these drugs in urine samples. Method precision was determined with RSDs values or=0.995). The developed CEC-MS method was then applied to the analysis of drugs of abuse in spiked urine samples, obtaining recovery data in the range 80-95%.


Assuntos
Eletrocromatografia Capilar/métodos , Drogas Ilícitas/urina , Espectrometria de Massas/métodos , Anfetaminas/isolamento & purificação , Anfetaminas/urina , Cocaína/isolamento & purificação , Cocaína/urina , Humanos , Drogas Ilícitas/isolamento & purificação , Modelos Lineares , Morfina/isolamento & purificação , Morfina/urina , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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