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2.
Ther Drug Monit ; 36(2): 218-24, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24067260

RESUMO

BACKGROUND: Recently, high-dose oral synthetic delta-9-tetrahydrocannabinol (THC) was shown to alleviate cannabis withdrawal symptoms. The present data describe cannabinoid pharmacokinetics in chronic, daily cannabis smokers who received high-dose oral THC pharmacotherapy and later a smoked cannabis challenge. METHODS: Eleven daily cannabis smokers received 0, 30, 60, or 120 mg/d THC for four 5-day medication sessions, each separated by 9 days of ad libitum cannabis smoking. On the fifth day, participants were challenged with smoking one 5.9% THC cigarette. Plasma collected on the first and fifth days was quantified by two-dimensional gas chromatography mass spectrometer for THC, 11-hydroxy-THC (11-OH-THC), and 11-nor-9-carboxy-THC (THCCOOH). Linear ranges (ng/mL) were 0.5-100 for THC, 1-50 for 11-OH-THC, and 0.5-200 for THCCOOH. RESULTS: During placebo dosing, THC, 11-OH-THC, and THCCOOH concentrations consistently decreased, whereas all cannabinoids increased dose dependently during active dronabinol administration. THC increase over time was not significant after any dose, 11-OH-THC increased significantly during the 60- and 120-mg/d doses, and THCCOOH increased significantly only during the 120-mg/d dose. THC, 11-OH-THC, and THCCOOH concentrations peaked within 0.25 hours after cannabis smoking, except after 120 mg/d THC when THCCOOH peaked 0.5 hours before smoking. CONCLUSIONS: The significant withdrawal effects noted during placebo dronabinol administration were supported by significant plasma THC and 11-OH-THC concentration decreases. During active dronabinol dosing, significant dose-dependent increases in THC and 11-OH-THC concentrations support withdrawal symptom suppression. THC concentrations after cannabis smoking were only distinguishable from oral THC doses for 1 hour, too short a period to feasibly identify cannabis relapse. THCCOOH/THC ratios were higher 14 hours after overnight oral dronabinol abstinence but cannot distinguish oral THC dosing from the smoked cannabis intake.


Assuntos
Canabinoides/sangue , Canabinoides/uso terapêutico , Dronabinol/sangue , Dronabinol/uso terapêutico , Abuso de Maconha/sangue , Abuso de Maconha/tratamento farmacológico , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Adolescente , Adulto , Canabinoides/farmacocinética , Relação Dose-Resposta a Droga , Método Duplo-Cego , Dronabinol/farmacocinética , Feminino , Humanos , Masculino , Fumar Maconha/sangue , Fumar Maconha/tratamento farmacológico , Pessoa de Meia-Idade , Síndrome de Abstinência a Substâncias/sangue , Adulto Jovem
3.
Anal Bioanal Chem ; 406(17): 4117-28, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24828976

RESUMO

Oral fluid (OF) enables non-invasive sample collection for on-site drug testing, but performance of on-site tests with occasional and frequent smokers' OF to identify cannabinoid intake requires further evaluation. Furthermore, as far as we are aware, no studies have evaluated differences between cannabinoid disposition among OF collection devices with authentic OF samples after controlled cannabis administration. Fourteen frequent (≥4 times per week) and 10 occasional (less than twice a week) adult cannabis smokers smoked one 6.8% ∆(9)-tetrahydrocannabinol (THC) cigarette ad libitum over 10 min. OF was collected with the StatSure Saliva Sampler, Oral-Eze, and Draeger DrugTest 5000 test cassette before and up to 30 h after cannabis smoking. Test cassettes were analyzed within 15 min and gas chromatography-mass spectrometry cannabinoid results were obtained within 24 h. Cannabinoid concentrations with the StatSure and Oral-Eze devices were compared and times of last cannabinoid detection (t(last)) and DrugTest 5000 test performance were assessed for different cannabinoid cutoffs. 11-nor-9-Carboxy-THC (THCCOOH) and cannabinol concentrations were significantly higher in Oral-Eze samples than in Stat-Sure samples. DrugTest 5000 t(last) for a positive cannabinoid test were median (range) 12 h (4-24 h) and 21 h (1- ≥ 30 h) for occasional and frequent smokers, respectively. Detection windows in screening and confirmatory tests were usually shorter for occasional than for frequent smokers, especially when including THCCOOH ≥20 ng L(-1) in confirmation criteria. No differences in t(last) were observed between collection devices, except for THC ≥2 µg L(-1). We thus report significantly different THCCOOH and cannabinol, but not THC, concentrations between OF collection devices, which may affect OF data interpretation. The DrugTest 5000 on-site device had high diagnostic sensitivity, specificity, and efficiency for cannabinoids.


Assuntos
Métodos Analíticos de Preparação de Amostras/métodos , Canabinoides/química , Drogas Ilícitas/química , Saliva/química , Adulto , Métodos Analíticos de Preparação de Amostras/instrumentação , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Imunoensaio/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
J Appl Lab Med ; 9(3): 573-578, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38300648

RESUMO

BACKGROUND: An erroneously high tacrolimus level was reported to a clinician. A root cause analysis investigation failed to determine the cause of the error. It was suspected that the incorrect preanalytical extraction reagent and procedure was used during testing; however, how this would affect the assayed drug concentration was unclear. Here we investigated the effect of the substitution of sirolimus, tacrolimus, and cyclosporine extraction reagents on assayed drug concentration. METHODS: Tacrolimus, sirolimus, and cyclosporine concentration were measured on the Abbott Architect i2000 analyzer. Each assay requires a preanalytical extraction step, with a distinct reagent. We investigated the effect of the substitution of the extraction reagents and procedure between the 3 assays on the measured drug concentration. Two experiments were performed, one on samples of known drug concentration and one on samples with no drug present. RESULTS: Substituting cyclosporine and sirolimus extraction procedures increased assayed tacrolimus concentrations from 5.6 to 8.47 (+51.25%) and 8.13 (+45.18%) ng/mL, respectively. Extraction procedure substitutions decreased assayed sirolimus from 13.63 to 4.60 (-66.25%) and 8.07 (-40.79%) ng/mL for cyclosporine and tacrolimus. Cyclosporine concentration increased from 274.60 to 391.30 (+42.50%) ng/mL using sirolimus extraction reagents and to 757.30 (+175.78%) ng/mL using tacrolimus extraction reagents. Cross-reactivity was observed between the tacrolimus assay and sirolimus and cyclosporine extraction reagents. CONCLUSIONS: Significant changes, both positive and negative, are observed in assayed drug concentration when incorrect extraction procedures are used in the Abbott i2000 tacrolimus, sirolimus, and cyclosporine assays. Preanalytic extraction procedures should be investigated when performing root cause analysis for erroneous therapeutic drug values.


Assuntos
Ciclosporina , Imunossupressores , Sirolimo , Tacrolimo , Tacrolimo/sangue , Tacrolimo/análise , Sirolimo/sangue , Sirolimo/análise , Ciclosporina/sangue , Ciclosporina/análise , Humanos , Imunossupressores/sangue , Imunossupressores/análise , Monitoramento de Medicamentos/métodos , Automação Laboratorial
5.
Clin Chem ; 59(12): 1770-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23938457

RESUMO

BACKGROUND: Oral Δ(9)-tetrahydrocannabinol (THC) is effective for attenuating cannabis withdrawal and may benefit treatment of cannabis use disorders. Oral fluid (OF) cannabinoid testing, increasing in forensic and workplace settings, could be valuable for monitoring during cannabis treatment. METHODS: Eleven cannabis smokers resided on a closed research unit for 51 days and received daily 0, 30, 60, and 120 mg of oral THC in divided doses for 5 days. There was a 5-puff smoked cannabis challenge on the fifth day. Each medication session was separated by 9 days of ad libitum cannabis smoking. OF was collected the evening before and throughout oral THC sessions and analyzed by 2-dimensional GC-MS for THC, cannabidiol (CBD), cannabinol (CBN), 11-hydroxy-THC (11-OH-THC), and 11-nor-9-carboxy-THC (THCCOOH). RESULTS: During all oral THC administrations, THC OF concentrations decreased to ≤ 78.2, 33.2, and 1.4 µg/L by 24, 48, and 72 h, respectively. CBN also decreased over time, with concentrations 10-fold lower than THC, with none detected beyond 69 h. CBD and 11-OH-THC were rarely detected, only within 19 and 1.6 h after smoking, respectively. THCCOOH OF concentrations were dose dependent and increased over time during 120-mg THC dosing. After cannabis smoking, THC, CBN, and THCCOOH concentrations showed a significant dose effect and decreased significantly over time. CONCLUSIONS: Oral THC dosing significantly affected OF THCCOOH but minimally contributed to THC OF concentrations; prior ad libitum smoking was the primary source of THC, CBD, and CBN. Higher cannabinoid concentrations following active oral THC administrations vs placebo suggest a compensatory effect of THC tolerance on smoking topography.


Assuntos
Canabinoides/análise , Dronabinol/uso terapêutico , Fumar Maconha , Saliva/química , Administração Oral , Adulto , Estudos Cross-Over , Dronabinol/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Anal Bioanal Chem ; 405(23): 7269-79, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23831756

RESUMO

Oral fluid (OF) is a valuable biological alternative for clinical and forensic drug testing. Evaluating OF to plasma (OF/P) cannabinoid ratios provides important pharmacokinetic data on the disposition of drug and factors influencing partition between matrices. Eleven chronic cannabis smokers resided on a closed research unit for 51 days. There were four 5-day sessions of 0, 30, 60, and 120 mg oral ∆(9)-tetrahydrocannabinol (THC)/day followed by a five-puff smoked cannabis challenge on Day 5. Each session was separated by 9 days ad libitum cannabis smoking. OF and plasma specimens were analyzed for THC and metabolites. During ad libitum smoking, OF/P THC ratios were high (median, 6.1; range, 0.2-348.5) within 1 h after last smoking, decreasing to 0.1-20.7 (median, 2.1) by 13.0-17.1 h. OF/P THC ratios also decreased during 5-days oral THC dosing, and after the smoked cannabis challenge, median OF/P THC ratios decreased from 1.4 to 5.5 (0.04-245.6) at 0.25 h to 0.12 to 0.17 (0.04-5.1) at 10.5 h post-smoking. In other studies, longer exposure to more potent cannabis smoke and oromucosal cannabis spray was associated with increased OF/P THC peak ratios. Median OF/P 11-nor-9-carboxy-THC (THCCOOH) ratios were 0.3-2.5 (range, 0.1-14.7) ng/µg, much more consistent in various dosing conditions over time. OF/P THC, but not THCCOOH, ratios were significantly influenced by oral cavity contamination after smoking or oromucosal spray of cannabinoid products, followed by time-dependent decreases. Establishing relationships between OF and plasma cannabinoid concentrations is essential for making inferences of impairment or other clinical outcomes from OF concentrations.


Assuntos
Canabinoides/sangue , Dronabinol/sangue , Alucinógenos/sangue , Fumar Maconha , Saliva/química , Adulto , Calibragem , Canabinoides/farmacocinética , Dronabinol/farmacocinética , Cromatografia Gasosa-Espectrometria de Massas , Alucinógenos/farmacocinética , Humanos , Limite de Detecção
7.
J Biol Chem ; 286(31): 27494-505, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21680731

RESUMO

Ewing sarcoma family of tumors (ESFT) is a group of aggressive pediatric malignancies driven by the EWS-FLI1 fusion protein, an aberrant transcription factor up-regulating specific target genes, such as neuropeptide Y (NPY) and its Y1 and Y5 receptors (Y5Rs). Previously, we have shown that both exogenous NPY and endogenous NPY stimulate ESFT cell death via its Y1 and Y5Rs. Here, we demonstrate that this effect is prevented by dipeptidyl peptidases (DPPs), which cleave NPY to its shorter form, NPY(3-36), not active at Y1Rs. We have shown that NPY-induced cell death can be abolished by overexpression of DPPs and enhanced by their down-regulation. Both NPY treatment and DPP blockade activated the same cell death pathway mediated by poly(ADP-ribose) polymerase (PARP-1) and apoptosis-inducing factor (AIF). Moreover, the decrease in cell survival induced by DPP inhibition was blocked by Y1 and Y5R antagonists, confirming its dependence on endogenous NPY. Interestingly, similar levels of NPY-driven cell death were achieved by blocking membrane DPPIV and cytosolic DPP8 and DPP9. Thus, this is the first evidence of these intracellular DPPs cleaving releasable peptides, such as NPY, in live cells. In contrast, another membrane DPP, fibroblast activation protein (FAP), did not affect NPY actions. In conclusion, DPPs act as survival factors for ESFT cells and protect them from cell death induced by endogenous NPY. This is the first demonstration that intracellular DPPs are involved in regulation of ESFT growth and may become potential therapeutic targets for these tumors.


Assuntos
Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo , Sarcoma de Ewing/metabolismo , Linhagem Celular Tumoral , Humanos , RNA Interferente Pequeno , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sarcoma de Ewing/enzimologia , Sarcoma de Ewing/patologia
8.
J Pathol Inform ; 13: 2, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35136670

RESUMO

BACKGROUND: Pandemics are unpredictable and can rapidly spread. Proper planning and preparation for managing the impact of outbreaks is only achievable through continuous and systematic collection and analysis of health-related data. We describe our experience on how to comply with required reporting and develop a robust platform for surveillance data during an outbreak. MATERIALS AND METHODS: At Mount Sinai Health System, New York City, we applied Visiun, a laboratory analytics dashboard, to support main response activities. Epic System Inc.'s SlicerDicer application was used to develop clinical and research reports. We followed World Health Organization (WHO); federal and state guidelines; departmental policies; and expert consultation to create the framework. RESULTS: The developed dashboard integrated data from scattered sources are used to seamlessly distribute reports to key stakeholders. The main report categories included federal, state, laboratory, clinical, and research. The first two groups were created to meet government and state reporting requirements. The laboratory group was the most comprehensive category and included operational reports such as performance metrics, technician performance assessment, and analyzer metrics. The close monitoring of testing volumes and lab operational efficiency was essential to manage increasing demands and provide timely and accurate results. The clinical data reports were valuable for proper managing of medical surge requirements, such as healthcare workforce and medical supplies. The reports included in the research category were highly variable and depended on healthcare setting, research priorities, and available funding. We share a few examples of queries that were included in the designed framework for research projects. CONCLUSION: We reviewed here the key components of a conceptual surveillance framework required for a robust response to COVID-19 pandemics. We demonstrated leveraging a lab analytics dashboard, Visiun, combined with Epic reporting tools to function as a surveillance system. The framework could be used as a generic template for possible future outbreak events.

9.
Clin Chem ; 57(1): 122-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21097676

RESUMO

BACKGROUND: Accurate measurement of free thyroxine (FT(4)) is important for diagnosing and managing thyroid disorders. Most laboratories measure FT(4) by direct analogue immunoassay methods. The validity of these methods have recently been questioned. The inverse log-linear relationship between FT(4) and thyroid-stimulating hormone (TSH) is well described and provides a physiological rationale on which to base an evaluation of FT(4) assays. METHODS: The study included 109 participants for whom FT(4) measurement was requested by their clinician. Samples were selected for inclusion to reflect a wide spectrum of TSH and albumin results. FT(4) and TSH were measured by use of the Siemens Immulite immunoassay (IA). FT(4) was also measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) (MS-FT(4)). RESULTS: The inverse log-linear correlation coefficient between TSH and FT(4) was significantly better (P < 0.0001) for MS-FT(4) (0.84, 95% CI, 0.77-0.88) than for IA-FT(4) (0.45, 95% CI, 0.29-0.59). IA-FT(4) showed a significant correlation with albumin (Spearman correlation coefficient 0.45, 95% CI, 0.29-0.5, P < 0.0001) and thyroxine-binding globulin (TBG) (Spearman correlation coefficient 0.23, 95% CI, 0.05-0.41, P = 0.02). In contrast, FT(4) measurement by LC-MS/MS did not show a significant correlation with albumin or TBG. CONCLUSIONS: The inverse log-linear relationship between FT(4) and TSH was significantly better for FT(4) measured by LC-MS/MS than by IA. The MS-FT(4) method therefore provides FT(4) results that agree clinically with those obtained for TSH. Additionally, the significant correlation between IA-FT(4) with albumin and TBG suggests that this FT(4) method depends on binding protein concentrations and consequently does not accurately reflect FT(4).


Assuntos
Tireotropina/sangue , Tiroxina/sangue , Albuminas/análise , Humanos , Imunoensaio , Conceitos Matemáticos , Estudos Prospectivos , Curva ROC , Espectrometria de Massas em Tandem , Globulina de Ligação a Tiroxina/análise
10.
J Clin Neuromuscul Dis ; 22(4): 228-231, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34019009

RESUMO

ABSTRACT: Elsberg syndrome is a rare cause of lumbosacral radiculitis with concomitant thoracic and lumbosacral myelitis that can be seen after an acute or reactivated viral infection. After the initial coronavirus surge in New York City, a 68-year-old man developed progressive lower extremity weakness and a defined sensory level at the lower abdomen. He had highly elevated SARS-CoV-2 IgG antibodies despite an absence of preceding COVID-19 symptoms. Serial electrodiagnostic testing revealed absent lower extremity late responses, with otherwise normal distal sensorimotor conductions. Electromyography revealed active neurogenic changes and reduced motor unit recruitment in the L3-L4 myotomes. Treatment with methylprednisolone and intravenous immunoglobulin was followed by minimal clinical improvement but re-emergence of the lower extremity late responses on electrodiagnostic testing. We report here, to the best of our knowledge, the first case of suspected COVID-19-associated Elsberg syndrome, which expands the spectrum of neuromuscular manifestations associated with SARS-CoV-2 infection and sheds light on ways to approach diagnostic and treatment options for these patients.


Assuntos
COVID-19/complicações , Mielite/etiologia , Radiculopatia/etiologia , Idoso , Anti-Inflamatórios/uso terapêutico , Eletrodiagnóstico , Eletromiografia , Humanos , Imunoglobulina G/análise , Imageamento por Ressonância Magnética , Masculino , Metilprednisolona/uso terapêutico , Debilidade Muscular/etiologia , Mielite/diagnóstico , Condução Nervosa , Radiculopatia/diagnóstico , Coluna Vertebral/diagnóstico por imagem , Síndrome , Resultado do Tratamento
11.
FEBS J ; 275(3): 458-69, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18167139

RESUMO

IbeA of Escherichia coli K1 was cloned, expressed and purified as a His(6)-tag fusion protein. The purified fusion protein inhibited E. coli K1 invasion of human brain microvascular endothelial cells and was heat-modifiable. The structural and functional aspects, along with equilibrium unfolding of IbeA, were studied in solution. The far-UV CD spectrum of IbeA at pH 7.0 has a strong negative peak at 215 nm, indicating the existence of beta-sheet-like structure. The acidic unfolding curve of IbeA at pH 2.0 shows the existence of a partially unfolded molecule (molten globule-like structure) with beta-sheet-like structure and displays strong 8-anilino-2-naphthyl sulfonic acid (ANS) binding. The pH dependent intrinsic fluorescence of IbeA was biphasic. At pH 2.0, IbeA exists in a partially unfolded state with characteristics of a molten globule-like state, and the protein is in extended beta-sheet conformation and exhibits strong ANS binding. Guanidine hydrochloride denaturation of IbeA in the molten globule-like state is noncooperative, contrary to the cooperativity seen with the native protein, suggesting the presence of two domains (possibly) in the molecular structure of IbeA, with differential unfolding stabilities. Furthermore, tryptophan quenching studies suggested the exposure of aromatic residues to solvent in this state. Acid denatured unfolding of IbeA monitored by far-UV CD is non-cooperative with two transitions at pH 3.0-1.5 and 1.5-0.5. At lower pH, IbeA unfolds to the acid-unfolded state, and a further decrease in pH to 2.0 drives the protein to the A state. The presence of 0.5 m KCl in the solvent composition directs the transition to the A state by bypassing the acid-unfolded state. Additional guanidine hydrochloride induced conformational changes in IbeA from the native to the A-state, as monitored by near- and far-UV CD and ANS-fluorescence.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Proteínas de Membrana/metabolismo , Western Blotting , Encéfalo/irrigação sanguínea , Encéfalo/citologia , Células Cultivadas , Dicroísmo Circular , Células Endoteliais/microbiologia , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/genética , Microscopia de Fluorescência , Dobramento de Proteína , Prótons
12.
Artigo em Inglês | MEDLINE | ID: mdl-28222335

RESUMO

BACKGROUND: Very sensitive measurements of serum estrogens and testosterone are important in adult and pediatric endocrinology and immunoassays are known to lack the required performance at very low levels. Our aim was to develop a sensitive HPLC-MS/MS assay for both estradiol (E2) and testosterone (Te) in serum without the need for chemical derivatization and using commercially available calibrators. METHODS: Serum samples were prepared by the addition of internal standards followed by extraction using hexane:ethyl acetate. Chromatographic separation was achieved using a C18 column and mass spectrometry was performed in both positive and negative ion modes. RESULTS: The lower limits of quantitation (LLOQs) of E2 and Te were 5pg/mL and 1ng/dL, respectively. The analytical measurement range (AMR) for E2 was 5-600pg/mL and 1-1,170ng/dL for Te. Assay accuracy was determined both by comparison with a LC-MS/MS method performed at a national laboratory and the CDC HoSt program. Comparison with samples analyzed by both methods showed excellent correlation. Within-day (N=10) and between-day (N=20) CVs at concentrations spanning the AMR were less than 7% for both analytes. CONCLUSION: We have developed an accurate and highly sensitive assay to measure E2 and Te levels in serum by HPLC-MS/MS without chemical derivatization and using commercially available calibrators.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Estradiol/sangue , Espectrometria de Massas em Tandem/métodos , Testosterona/sangue , Acetatos/química , Adulto , Estradiol/isolamento & purificação , Hexanos/química , Humanos , Limite de Detecção , Testosterona/isolamento & purificação
13.
Drug Test Anal ; 7(6): 494-501, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25220020

RESUMO

Oral fluid (OF) offers a simple, non-invasive, directly observable sample collection for clinical and forensic drug testing. Given that chronic cannabis smokers often engage in drug administration multiple times daily, evaluating OF cannabinoid pharmacokinetics during ad libitum smoking is important for practical development of analytical methods and informed interpretation of test results. Eleven cannabis smokers resided in a closed research unit for 51 days, and underwent four, 5-day oral delta-9-tetrahydrocannabinol (THC) treatments. Each medication period was separated by 9 days of ad libitum cannabis smoking from 12:00 to 23:00 h daily. Ten OF samples were collected from 9:00-22:00 h on each of the last ad libitum smoking days (Study Days 4, 18, 32, and 46). As the number of cannabis cigarettes smoked increased over the study days, OF THC, cannabinol (CBN), and 11-nor-9-carboxy-THC (THCCOOH) also increased with a significant effect of time since last smoking (Δtime; range, 0.0-17.4 h) and ≥88% detection rates; concentrations on Day 4 were significantly lower than those on Days 32 and 46 but not Day 18. Within 30 min of smoking, median THC, CBN, and THCCOOH concentrations were 689 µg/L, 116 µg/L, and 147 ng/L, respectively, decreasing to 19.4 µg/L, 2.4 µg/L, and 87.6 ng/L after 10 h. Cannabidiol and 11-hydroxy-THC showed overall lower detection rates of 29 and 8.6%, respectively. Cannabinoid disposition in OF was highly influenced by Δtime and composition of smoked cannabis. Furthermore, cannabinoid OF concentrations increased over ad libitum smoking days, in parallel with increased cannabis self-administration, possibly reflecting development of increased cannabis tolerance.


Assuntos
Canabinoides/análise , Fumar Maconha/metabolismo , Saliva/química , Detecção do Abuso de Substâncias/métodos , Administração Oral , Adulto , Canabidiol/análise , Canabinol/análise , Dronabinol/administração & dosagem , Dronabinol/análogos & derivados , Dronabinol/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autoadministração , Fatores de Tempo
14.
Drug Test Anal ; 6(10): 1002-10, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24652685

RESUMO

Oral fluid (OF) is an increasingly popular alternative matrix for drug testing, with cannabinoids being the most commonly identified illicit drug. Quantification of multiple OF cannabinoids and understanding differences in OF cannabinoid pharmacokinetics between frequent and occasional smokers improve test interpretation. The new Oral-Eze® OF collection device has an elution buffer that stabilizes analytes and improves drug recovery from the collection pad; however, its performance has not been independently evaluated. After controlled smoking of a 6.8% Δ(9) -tetrahydrocannabinol (THC) cannabis cigarette by frequent and occasional smokers, OF was collected with the Oral-Eze device for up to 30 h. Samples were analyzed for multiple cannabinoids by a validated 2D-GC-MS method. Frequent smokers had significantly greater OF THCCOOH concentrations than occasional smokers at all times, and showed positive results for a significantly longer time. We evaluated multiple cannabinoid cut-offs; the shortest last detection times were observed when THC ≥ 1 µg/L was combined with CBD or CBN ≥ 1 µg/L. With these cut-offs, last detection times(1-13.5 h) were not significantly different between groups, demonstrating suitability for short-term cannabinoid detection independent of smoking history. Cut-offs utilizing THC alone or combined with THCCOOH showed significantly different last detection times between groups. The widest detection windows were observed with THC ≥ 1 or 2 µg/L or THCCOOH ≥ 20 ng/L. Our data illustrate the effectiveness of the Oral-Eze® device for OF collection, the impact of self-administered smoked cannabis history on OF cannabinoid results, and the ability to improve interpretation and tailor OF cannabinoid cut-offs to fulfill the detection window needs of a given program.


Assuntos
Canabinoides/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Fumar Maconha/metabolismo , Detecção do Abuso de Substâncias/métodos , Adulto , Canabinoides/metabolismo , Dronabinol/análise , Dronabinol/metabolismo , Feminino , Humanos , Masculino , Fumar Maconha/epidemiologia , Saliva/química , Fatores de Tempo , Adulto Jovem
15.
Clin Chim Acta ; 411(11-12): 806-11, 2010 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-20188087

RESUMO

BACKGROUND: Cyclosporine (CsA) monitoring is essential for transplant success. We report a performance study of the recently released, fully automated Siemens ADVIA Centaur CsA assay. METHODS: Whole blood samples from 248 transplant patients were prepared using a new 1-step extraction method. Performance evaluations vs. HPLC-tandem MS (LC-MS/MS), Abbott TDx and AxSYM assays were conducted according to CLSI EP5-A2 and EP9-A2 guidelines. RESULTS: The correlation coefficient for LC-MS/MS and ADVIA Centaur was > or = 0.97 at each site, and for each transplant type. Regression analysis yielded y=0.94x+19 for all sites: 95% CI=0.91-0.96 (slope) and 10-28 (intercept). Absolute and relative bias was minimal for C0 and C2 sampling. Centaur vs. Abbott TDx and AxSYM assays: y = 0.72x+6, r = 0.98, 95% CI = 0.70-0.73 (slope), 3-9 (intercept); and y = 0.69x+18, r = 0.97, 95% CI = 0.67-0.71 (slope), 8-27(intercept). Within run CVs were 4.5%-7.1%, total CVs were 5.3%-7.7%. CONCLUSIONS: The ADVIA Centaur assay compared favorably with LC-MS/MS and Abbott assays, displaying good correlation for all transplant types and methods.


Assuntos
Ciclosporina/sangue , Monitoramento de Medicamentos/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ligação Competitiva , Ciclosporina/isolamento & purificação , Monitoramento de Medicamentos/métodos , Feminino , Imunoensaio de Fluorescência por Polarização/métodos , Imunoensaio de Fluorescência por Polarização/normas , Humanos , Imunossupressores/sangue , Imunossupressores/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Valores de Referência , Transplante/normas , Adulto Jovem
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