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Lanaro R.,University of Campinas | Costa J.L.,University of Campinas | Costa J.L.,Criminalistics Institute of Sao Paulo | Fernandes L.C.,University of Campinas | And 3 more authors.
Journal of Analytical Toxicology | Year: 2011

The aim of this work was to develop a simple and fast method for the detection of paraquat in oral fluid, plasma, and urine by capillary electrophoresis with diode-array detection (CE-DAD), to diagnose of acute poisoning related to this herbicide. The use of oral fluid in analytical toxicology has been established for drugs of abuse, but not for diagnosis of pesticides poisoning. Oral fluid was collected without stimulation using absorbent cotton swabs. Sample preparation included diluting, vortex mixing, and centrifuging of biological fluid, using ethyl paraquat as internal standard. CE-DAD analyses were performed in a fused-silica capillary, and separation was performed under constant voltage condition of 21 kV, with detection at 195 nm. The electrolyte was a 40 mmol/L phosphate buffer at pH 2.50. The proposed method provided a fast and simple assay for the determination of paraquat in human oral fluid, plasma, and urine. To our knowledge, this is the first mention of use of oral fluid as a biological fluid diagnosis of quaternary ammonium herbicide poisoning. After validation, the method was applied to two cases of acute poisoning by this herbicide. Source


Alvarenga T.A.,University of Sao Paulo | Polesel D.N.,University of Sao Paulo | Matos G.,University of Sao Paulo | Garcia V.A.,Grande Rio University | And 3 more authors.
Behavioural Processes | Year: 2014

The ingestion of the beverage Ayahuasca usually occurs in religious ceremonies that are performed during the night leading to sleep deprivation. The purpose of the present study was to characterize the acute effects of Ayahuasca upon the sexual response of sleep deprived male rats. One group of sexually experienced male Wistar rats were submitted to a paradoxical sleep deprivation (PSD) protocol for 96h, while another group spent the same amount of time in the home cage (CTRL). After this period, either saline or Ayahuasca drink (250, 500 and 1000μgmL-1) was administered by gavage and sexual behavior and hormonal concentrations were measured. Ayahuasca alone significantly decreased sexual performance at all doses. However, in sleep deprived rats, the lower dose increased sexual performance while the intermediate dose produced a detrimental effect on sexual response compared to the CTRL rats at the same dose. Regarding the hormonal analyses, a lower testosterone concentration was observed in sleep-deprived saline rats in relation to the CTRL group. Progesterone was significantly lower only in PSD rats at the dose 500μgmL-1 compared with CTRL-500μgmL-1 group. Corticosterone was unchanged among the groups evaluated. Our results suggest that Ayahuasca intake markedly impaired sexual performance alone, but, when combined with sleep deprivation, had significant, but heterogeneous, effects on male sexual response. © 2014. Source


Newmeyer M.N.,U.S. National Institute on Drug Abuse | Newmeyer M.N.,University of Maryland, Baltimore | Concheiro M.,U.S. National Institute on Drug Abuse | Concheiro M.,John Jay College of Criminal Justice | And 6 more authors.
Forensic Toxicology | Year: 2015

Opiates are included in drug testing programs because of their psychoactive properties and abuse potential, but excluding poppy seed ingestion is necessary to correctly interpret positive opiate results. There are few available data for plasma and oral fluid (OF) following poppy seed ingestion, and most do not report opiate content in the ingested poppy seeds. We quantified plasma and OF morphine and codeine concentrations via a fully validated liquid chromatography–tandem mass spectrometry method after controlled administration of two doses (8 h apart) of raw, uncooked poppy seeds (45-g) each containing 15.7 mg of morphine and 3.1 mg of codeine. Simultaneous specimens were collected before and up to 32 h after the first dose. Maximum OF morphine and codeine concentrations (3.6–110 and 2.1–22.4 µg/l, respectively) were significantly greater than simultaneously collected maximum plasma concentrations (2.8–9.3 and 1.1–2.0 µg/l, respectively). OF and plasma morphine and codeine concentrations were significantly correlated, but large variabilities preclude plasma concentration estimations from OF results. The median OF morphine time of first detection (tfirst) and time of last detection (tlast) were both 0.5 h with cutoffs from 20 to 40 µg/l, with 0.9–6.7 % positive specimens. Codeine was detected only at low 15–20 µg/l OF cutoffs; median tfirst and tlast were 0.5–1.3 h and 0.5–2.3 h, respectively, with only 0.4–1.8 % specimens positive. After two large, raw, uncooked poppy seed doses, significant differences between plasma and OF opiate pharmacokinetics were observed. Less than 6.7 % positive OF tests and a median morphine OF detection time of only 0.5 h with cutoffs from 20 to 40 µg/l suggest that few OF positive morphine tests can be explained by poppy seed ingestion. © 2015, Japanese Association of Forensic Toxicology and Springer Japan (outside the USA). Source


De Souza Eller S.C.W.,University of Sao Paulo | Flaiban L.G.,University of Sao Paulo | Paranhos B.A.P.B.,University of Sao Paulo | Da Costa J.L.,Criminalistics Institute of Sao Paulo | And 2 more authors.
Forensic Toxicology | Year: 2014

Marijuana abuse can be detected by means of toxicological analysis of the most important metabolite 11-nor-9-carboxy-Δ9- tetrahydrocannabinol (THC-COOH) in urine samples. The aim of this study is the establishment of the detailed procedure for analysis of THC-COOH in urine by combination of hollow fiber-liquid phase microextraction (HF-LPME) and gas chromatography-mass spectrometry (GC-MS). The conditions of hydrolysis and extraction were optimized. The method was shown to be very simple and rapid, and a low amount of organic solvent was necessary for extraction. The limit of detection was 1.5 ng/ml. The calibration curves were linear over the specified range (2.0-170 ng/ml; r2 > 0.99). The main sources of uncertainty were found to be analyte concentration, accuracy, method precision and sample volume. The effect of the analyte concentration on the overall combined uncertainty was most significant. The developed method was successfully applied to a human urine standard reference material at two levels of concentration. The obtained relative combined uncertainty was 8 %, which can be considered acceptable according to international guidelines. The present method seems very useful in clinical and forensic toxicology, because of its simplicity, rapidness and inexpensiveness. © 2014 Japanese Association of Forensic Toxicology and Springer. Source


Concheiro M.,U.S. National Institute on Drug Abuse | Newmeyer M.N.,U.S. National Institute on Drug Abuse | Newmeyer M.N.,University of Maryland, Baltimore | da Costa J.L.,U.S. National Institute on Drug Abuse | And 5 more authors.
Drug Testing and Analysis | Year: 2015

Opiates are an important drug class in drug testing programmes. Ingestion of poppy seeds containing morphine and codeine can yield positive opiate tests and mislead result interpretation in forensic and clinical settings. Multiple publications evaluated urine opiate concentrations following poppy seed ingestion, but only two addressed oral fluid (OF) results; neither provided the ingested morphine and codeine dosage. We administered two 45g raw poppy seed doses, each containing 15.7mg morphine and 3.1mg codeine, 8h apart to 17 healthy adults. All OF specimens were screened by on-site OF immunoassay Draeger DrugTest 5000, and confirmed with OF collected with Oral-Eze® device and quantified by liquid chromatography-tandem mass spectrometry (1μg/L morphine and codeine limits of quantification). Specimens (n=459) were collected before and up to 32h after the first dose. All specimens screened positive 0.5h after dosing and remained positive for 0.5-13h at Draeger 20μg/L morphine cut-off. Maximum OF morphine and codeine concentrations (Cmax) were 177 and 32.6μg/L, with times to Cmax (Tmax) of 0.5-1h and 0.5-2.5h post-dose, respectively. Windows of detection after the second dose extended at least 24h for morphine and to 18h for codeine. After both doses, the last morphine positive OF result was 1h with 40μg/L 2004 proposed US Substance Abuse and Mental Health Services Administration cut-off, and 0.5h with 95μg/L cut-off, recently recommended by the Driving under the Influence of Drugs and Medicines project. Positive OF morphine results are possible 0.5-1h after ingestion of 15.7mg of morphine in raw poppy seeds, depending on the cut-off employed. © 2014 John Wiley & Sons, Ltd. Source

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