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1.
Clin Toxicol (Phila) ; 59(6): 506-514, 2021 06.
Article in English | MEDLINE | ID: mdl-33118434

ABSTRACT

CONTEXT: Detecting marijuana use is a component of most urine drug screens targeting a single Δ9-tetrahydrocannabinol metabolite. Recently, the non-intoxicating cannabinoid, cannabidiol (CBD), has gained popular acceptance for a myriad of reasons. Commercially available CBD products sold without purity regulations have become ubiquitous. Many products contain trace tetrahydrocannabinol. Long-term or high dose use of CBD products can result in tetrahydrocannabinol exposures, potentially producing a positive marijuana drug test. These results are not false positives since marijuana biomarkers are present, but inaccurately identify donors as marijuana users. Addressing this conundrum, we developed an assay discriminating marijuana use from the use of CBD contaminated with tetrahydrocannabinol. METHODS: Following the synthesis of a primary CBD metabolite, a LC-MS/MS assay was developed measuring the urinary metabolites tetrahydrocannabinol, 11-nor-carboxy-Δ9-tetrahydrocannabinol, CBD, and 7-carboxy-cannabidiol. The assay was utilized on 425 patients claiming CBD use, and sixteen samples from trusted users of commercial CBD products. RESULTS AND DISCUSSION: Clear data clusters enabled metabolic cut-points assignments. Forty-three percent of samples contained CBD metabolites in ten-fold excess to tetrahydrocannabinol metabolites which was then used as a set point to classify donors as CBD users. An excess of tetrahydrocannabinol metabolites classify donors as marijuana users. Additionally, urine samples were procured from donors personally known to use commercial CBD ad libitum, yet abstain from tetrahydrocannabinol. Results from trusted users substantiated the use of the resulting metabolic ratios despite 11-carboxy-tetrahydrocannabinol measured in 75% of these samples. CONCLUSION: A method has been developed and utilized to distinguish marijuana use from tetrahydrocannabinol exposure from contaminated CBD use.


Subject(s)
Cannabidiol/urine , Dronabinol/metabolism , Marijuana Use/urine , Humans
2.
Pain Manag ; 9(5): 441-447, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31496363

ABSTRACT

Aim: Marijuana use has been postulated to modulate opioid use, dependence and withdrawal. Broad target drug testing results provide a unique perspective to identify any potential interaction between marijuana use and opioid use. Materials & methods: Using a dataset of approximately 800,000 urine drug test results collected from pain management patients of a time from of multiple years, creatinine corrected opioid levels were evaluated to determine if the presence of the primary marijuana marker 11-nor-carboxy-tetrahydrocannabinol (THC-COOH) was associated with statistical differences in excreted opioid concentrations. Results & conclusion: For each of the opioids investigated (codeine, morphine, hydrocodone, hydromorphone, oxycodone, oxymorphone, fentanyl and buprenorphine), marijuana use was associated with statistically significant lower urinary opiate levels than in samples without indicators of marijuana use.


Subject(s)
Analgesics, Opioid/therapeutic use , Analgesics, Opioid/urine , Marijuana Use/urine , Pain/drug therapy , Dronabinol/urine , Humans , Pain Management , Retrospective Studies
3.
Methods Mol Biol ; 1872: 199-209, 2019.
Article in English | MEDLINE | ID: mdl-30350292

ABSTRACT

Meconium, the first stool of a newborn, can be analyzed to identify prenatal exposure to drugs of abuse. Meconium accumulates in a fetus during the second and third trimesters of pregnancy providing a wide window of exposure. Identification of in utero drug exposure is essential for the diagnosis and treatment of infants for dependency/withdrawal caused from the exposure. However, testing of meconium samples is often cumbersome and time-consuming. Unlike liquid samples, meconium is a viscous, semisolid, tar-like substance that needs to be individually weighed prior to extraction. Additionally, the meconium matrix is not homogeneous and not easily mixed or extracted. A method for analyzing cocaine and metabolites as well as amphetamines in meconium utilizing ceramic homogenizers prior to salt-assisted liquid-liquid extraction and liquid chromatography tandem-mass spectrometry (LC-MS/MS) is presented.


Subject(s)
Amphetamines/pharmacokinetics , Chromatography, Liquid , Cocaine/pharmacokinetics , Liquid-Liquid Extraction/methods , Meconium/chemistry , Substance Abuse Detection/methods , Tandem Mass Spectrometry , Amphetamines/isolation & purification , Cocaine/isolation & purification , Humans , Salts
4.
J Anal Toxicol ; 42(6): 384-391, 2018 Jul 01.
Article in English | MEDLINE | ID: mdl-29471504

ABSTRACT

The recent increase in illicit opioids sold on the black market, cut into heroin and masqueraded as prescription pills prompts a significant public health concern. Most designer opioids possess unknown potencies and unknown pharmacokinetics and their unregulated, variable dosages lead to rashes of overdoses. Additionally, many of the designer opioids, especially the fentanyl analogs are significantly more potent than heroin. High-profile cases involving overdoses of U-47700 and carfentanil have been reported in the media; however, the true prevalence of these and other designer opioids is unknown. Independent LC-MS-MS screen and confirmation methods have been developed and validated to identify and quantify fentanyl, and 18 designer opioids and their metabolites; methods were then exercised on urine specimens from contract pain management clients. Assuming patients in a pain management program may have a higher probability to seek out self-medication, samples from pain management patients were investigated for designer opioids. Similarly, pain management patients identified as using heroin may be more likely to experiment with or be accidentally exposed to designer opioids, specimens screening positive for the heroin metabolite 6-acetylmorphine were specifically chosen for designer opioid screening. Within this small group of pain management and heroin-positive samples, nine designer opioids were detected at a total prevalence of 25%. When screening random pain management samples not positive for heroin, a considerably lower percentage of samples (<1%) were identified as positive for designer opioids. Furanyl fentanyl, fluorobutyryl fentanyl and acetylfentanyl were the most prevalent designer opioids detected in both test groups.


Subject(s)
Analgesics, Opioid/urine , Designer Drugs/analysis , Heroin Dependence/diagnosis , Pain Management/methods , Pain/drug therapy , Substance Abuse Detection/methods , Biotransformation , Chromatography, Liquid , Heroin Dependence/epidemiology , Heroin Dependence/urine , Humans , Pain/diagnosis , Pain/epidemiology , Pain/urine , Predictive Value of Tests , Prevalence , Reproducibility of Results , Tandem Mass Spectrometry , United States/epidemiology , Urinalysis
5.
J Anal Toxicol ; 41(5): 355-359, 2017 Jun 01.
Article in English | MEDLINE | ID: mdl-28379393

ABSTRACT

A wide range of concentrations are frequently observed when measuring drugs of abuse in urine toxicology samples; this is especially true for amphetamine and methamphetamine. Routine liquid chromatography-tandem mass spectrometry confirmatory methods commonly anchored at a 50 ng/mL lower limit of quantitation can span approximately a 100-fold concentration range before regions of non-linearity are reached deteriorating accurate quantitation and qualitative assessments. In our experience, approximately a quarter of amphetamine and methamphetamine positive samples are above a 5,000 ng/mL upper limit of quantitation and thus require reanalysis with dilution for accurate quantitative and acceptable qualitative results. We present here the development of an analytical method capable of accurately quantifying samples with concentrations spanning several orders of magnitude without the need for sample dilution and reanalysis. For each analyte the major isotopes were monitored for analysis through the lower concentration ranges (50-5,000 ng/mL), and the naturally occurring, low probability 13C2 isotopes were monitored for the analysis of the high concentration samples (5,000-100,000 ng/mL amphetamine and 5,000-200,000 ng/mL methamphetamine). The method simultaneously monitors transitions for the molecules containing only 12C and 13C2 isotopologues eliminating the need for re-extraction and reanalysis of high concentration samples.


Subject(s)
Amphetamine/urine , Methamphetamine/urine , Substance Abuse Detection/methods , Biological Assay , Humans , Probability
6.
J Anal Toxicol ; 41(5): 367-375, 2017 Jun 01.
Article in English | MEDLINE | ID: mdl-28369517

ABSTRACT

The illicit drug market has seen an increase in designer opioids, including fentanyl and methadone analogs, and other structurally unrelated opioid agonists. The designer opioid, furanyl fentanyl, is one of many fentanyl analogs clandestinely synthesized for recreational use and contributing to the fentanyl and opioid crisis. A method has been developed and validated for the analysis of furanyl fentanyl and furanyl norfentanyl in urine specimens from pain management programs. Approximately 10% of samples from a set of 500 presumptive heroin-positive urine specimens were found to contain furanyl fentanyl, with an average concentration of 33.8 ng/mL, and ranging from 0.26 to 390 ng/mL. Little to no furanyl norfentanyl was observed; therefore, the furanyl fentanyl specimens were further analyzed by untargeted high-resolution mass spectrometry to identify other metabolites. Multiple metabolites, including a dihydrodiol metabolite, 4-anilino-N-phenethyl-piperidine (4-ANPP) and a sulfate metabolite were identified. The aim of the presented study was to identify the major metabolite(s) of furanyl fentanyl and estimate their concentrations for the purpose of toxicological monitoring.


Subject(s)
Analgesics, Opioid/metabolism , Fentanyl/analogs & derivatives , Furans/metabolism , Illicit Drugs/metabolism , Substance Abuse Detection , Fentanyl/metabolism , Mass Spectrometry
7.
J Anal Toxicol ; 41(2): 121-126, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-27881620

ABSTRACT

Urine drug testing is common for workplace drug testing, prescription management, emergency medicine and the criminal justice system. Unsurprisingly, with the significant consequences based upon the results of urine drug testing, a donor in need of concealing the contents of their sample is highly motivated to cheat the process. Procedures and safeguards ensuring sample validity are well known, and include measuring sample temperature at the time of collection, and laboratory measurements of creatinine, specific gravity and pH. Synthetic urine samples are available and are designed to deceive all aspects of urine drug testing, including validity testing. These samples are sophisticated enough to contain biological levels of creatinine, and are at a physiological pH and specific gravity. The goal of our research was to develop new procedures designed to distinguish authentic samples from masquerading synthetic samples. We aimed to identify substances in commercial synthetic urines not expected to be present in a biological sample distinguishing fake specimens. Additionally, we aimed to identify and employ endogenous compounds in addition to creatinine for identifying biological samples. We successfully identified two compounds present in synthetic urines that are not present in biological samples and use them as markers of invalidity. Four new endogenous markers for validity were successfully evaluated. Validity assessment was further aided by monitoring metabolites of nicotine and caffeine. When the method was applied to patient samples, 2% of samples were identified as inconsistent with natural urine samples, even though they met the current acceptance criteria for creatinine, pH and specific gravity.


Subject(s)
Drug Monitoring/methods , Pharmaceutical Preparations/urine , Specimen Handling/standards , Substance Abuse Detection/methods , Urinalysis/standards , Biomarkers/urine , Creatinine/urine , Drug Monitoring/standards , Ethylene Glycols/urine , Humans , Substance Abuse Detection/standards , Thiazoles/urine
8.
J Anal Toxicol ; 36(9): 616-25, 2012.
Article in English | MEDLINE | ID: mdl-23024321

ABSTRACT

The leaves of the South Asian plant kratom are described as having stimulating effects at low doses, and opiate-like analgesic and euphoric effects at high doses. A long history of use and abuse has led to the classification of kratom as a controlled substance in its native Thailand and other South Asian countries. However, kratom is not controlled in the United States, and the ready availability of kratom has led to its emergence as an herbal drug of abuse. With the growing popularity of kratom, efficient procedures are needed to detect kratom use. In the current study, both ultra-high-performance liquid chromatography and high-performance liquid chromatography-tandem mass spectrometry methods have been developed and validated for monitoring the major alkaloids and metabolites found in urine following kratom use. The primary unique alkaloid mitragynine is quantified in human urine from 1.00-500.00 ng/mL using mitraphylline as an internal standard. In addition, two metabolites (5-desmethylmitragynine and 17-desmethyldihydromitragynine) and the related active, alkaloid 7-hydroxy-mitragynine, are simultaneously qualitatively monitored. The presence of analytes are confirmed by an information-dependent acquisition-enhanced product ion procedure generating full fragmentation data used to positively identify detected analytes. The validated method has been utilized for clinical and forensic analyses of urine for the detection of kratom use.


Subject(s)
Mitragyna/chemistry , Plant Leaves/chemistry , Secologanin Tryptamine Alkaloids/urine , Substance Abuse Detection/methods , Calibration , Chromatography, High Pressure Liquid/methods , Humans , Indole Alkaloids/urine , Oxindoles , Plant Extracts/chemistry , Reproducibility of Results , Tandem Mass Spectrometry/methods , Thailand
9.
Bioanalysis ; 3(16): 1837-46, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21877893

ABSTRACT

BACKGROUND: Patients with iron-deficiency anemia benefit from intravenous iron therapies. Development of these pharmaceutical agents requires pharmacokinetic studies monitoring levels of both the administered agent and transferrin-bound iron (TBI). Successful pharmacokinetic methods must discriminate iron species. RESULTS: Routine colorimetric procedures were used to reliably measure total iron and TBI following iron-sucrose administration. Iron was liberated from iron-sucrose allowing the determination of all circulating iron. Solid-phase sample processing allowed the measurement of TBI. Circulating iron-sucrose could then be calculated as the difference between total iron and TBI. CONCLUSION: A reproducible and robust spectrophotometric method was developed and validated for measuring total iron and TBI in human serum following iron-sucrose therapy.


Subject(s)
Anemia, Iron-Deficiency/drug therapy , Ferric Compounds/blood , Ferric Compounds/chemistry , Iron/blood , Iron/chemistry , Transferrin/metabolism , Colorimetry/methods , Female , Ferric Compounds/administration & dosage , Ferric Oxide, Saccharated , Glucaric Acid , Humans , Iron/administration & dosage , Reproducibility of Results , Spectrophotometry/methods
10.
Cell Cycle ; 8(17): 2802-9, 2009 Sep 01.
Article in English | MEDLINE | ID: mdl-19652536

ABSTRACT

Cdk2 was once believed to play an essential role in cell cycle progression, but cdk2(-/-) mice have minimal phenotypic abnormalities. In this study, we examined the role of cdk2 in hepatocyte proliferation, centrosome duplication and survival. Cdk2(-/-) hepatocytes underwent mitosis and had normal centrosome content after mitogen stimulation. Unlike wild-type cells, cdk2(-/-) liver cells failed to undergo centrosome overduplication in response to ectopic cyclin D1 expression. After mitogen stimulation in culture or partial hepatectomy in vivo, cdk2(-/-) hepatocytes demonstrated diminished proliferation. Cyclin D1 is a key mediator of cell cycle progression in hepatocytes, and transient expression of this protein is sufficient to promote robust proliferation of these cells in vivo. In cdk2(-/-) mice and animals treated with the cdk2 inhibitor seliciclib, cyclin D1 failed to induce hepatocyte cell cycle progression. Surprisingly, cdk2 ablation or inhibition led to massive hepatocyte and animal death following cyclin D1 transfection. In a transgenic model of chronic hepatic cyclin D1 expression, seliciclib induced hepatocyte injury and animal death, suggesting that cdk2 is required for survival of cyclin D1-expressing cells even in the absence of substantial proliferation. In conclusion, our studies demonstrate that cdk2 plays a role in liver regeneration. Furthermore, it is essential for centrosome overduplication, proliferation and survival of hepatocytes that aberrantly express cyclin D1 in vivo. These studies suggest that cdk2 may warrant further investigation as a target for therapy of liver tumors with constitutive cyclin D1 expression.


Subject(s)
Cell Cycle , Cyclin D1/metabolism , Cyclin-Dependent Kinase 2/physiology , Hepatocytes/enzymology , Animals , Cell Proliferation , Cell Survival , Cells, Cultured , Centrosome/metabolism , Cyclin A/metabolism , Cyclin E/metabolism , Cyclin-Dependent Kinase 2/genetics , Cyclin-Dependent Kinase 2/metabolism , Hepatocytes/cytology , Hepatocytes/metabolism , Liver Regeneration , Mice , Mice, Inbred BALB C , Mice, Knockout , Purines/pharmacology , Roscovitine , Time Factors , Transfection
11.
Cell Cycle ; 7(14): 2215-24, 2008 Jul 15.
Article in English | MEDLINE | ID: mdl-18635970

ABSTRACT

The D-type cyclins (D1, D2 and D3) are components of the cell cycle machinery and govern progression through G(1) phase in response to extracellular signals. Although these proteins are highly homologous and conserved in evolution, they contain distinct structural motifs and are differentially regulated in various cell types. Cyclin D1 appears to play a role in many different types of cancer, whereas cyclins D2 and D3 are less frequently associated with malignancy. In this study, we transiently expressed cyclin D1, D2 or D3 in hepatocytes and analyzed transcriptional networks regulated by each. All three D-type cyclins promoted robust hepatocyte proliferation and marked liver growth, although cyclin D3 stimulated less DNA synthesis than D1 or D2. Accordingly, the three D-type cyclins similarly activated genes associated with cell division. Cyclin D1 regulated transcriptional pathways involved in the metabolism of carbohydrates, lipids, amino acids, and other substrates, whereas cyclin D2 did not regulate these pathways despite having an equivalent effect on proliferation. Comparison of transcriptional profiles following 70% partial hepatectomy and cyclin D1 transduction revealed a highly significant overlap, suggesting that cyclin D1 may regulate diverse cellular processes in the regenerating liver. In summary, these studies provide the first comparative analysis of the transcriptional networks regulated by the D-type cyclins and provide insight into novel functions of these key cell cycle proteins. Further study of the unique targets of cyclin D1 should provide further insight into its prominent role in proliferation, growth and cancer.


Subject(s)
Cyclins/metabolism , Transcription, Genetic , Animals , Cell Cycle Proteins/genetics , Cell Proliferation , Cyclin D , Cyclin D1/genetics , Cyclin D1/metabolism , Cyclin D2 , Cyclin D3 , Cyclins/genetics , Gene Expression Profiling , Gene Expression Regulation , Hepatectomy , Hepatocytes/cytology , Hepatocytes/metabolism , Liver/growth & development , Liver/metabolism , Male , Mice , Mice, Inbred BALB C , Rats
12.
J Biol Chem ; 282(29): 21244-52, 2007 Jul 20.
Article in English | MEDLINE | ID: mdl-17517888

ABSTRACT

The control of hepatocyte growth is relevant to the processes of liver regeneration, development, metabolic homeostasis, and cancer. A key component of growth control is the protein kinase Akt, which acts downstream of mitogens and nutrients to affect protein translation and cell cycle progression. In this study, we found that transient transfection of activated Akt triggered a 3-4-fold increase in liver size within days but only minimal hepatocyte proliferation. Akt-induced liver growth was associated with marked up-regulation of cyclin E but not cyclin D1. Analysis of liver polyribosomes demonstrated that the post-transcriptional induction of cyclin E was associated with increased translational efficiency of this mRNA, suggesting that cell growth promotes expression of this protein through a translational mechanism that is distinct from the cyclin D-E2F pathway. Treatment of Akt-transfected mice with rapamycin only partially inhibited liver growth and did not prevent the induction of cyclin E protein, indicating that target of rapamycin activity is not necessary for this response. In the enlarged livers, cyclin E-Cdk2 complexes were present in high abundance but were inactive due to increased binding of p21 to these complexes. Akt transfection of p21(-/-) mice promoted liver growth, activation of Cdk2, and enhanced hepatocyte proliferation. In conclusion, growth promotes cyclin E expression through a novel translational mechanism in the liver, suggesting a new link between cell growth and the cell cycle machinery. Furthermore, p21 suppresses proliferation in the overgrown livers and may play a role in preventing cell cycle progression in response to organ size homeostatic mechanisms.


Subject(s)
Cyclin E/biosynthesis , Liver/metabolism , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Animals , Cell Cycle , Cell Proliferation , Cyclin D1/metabolism , Cyclin E/metabolism , Hepatocytes/metabolism , Male , Mice , Mice, Inbred BALB C , Mice, Transgenic , Models, Biological , Protein Biosynthesis , p21-Activated Kinases
13.
J Biol Chem ; 280(1): 768-76, 2005 Jan 07.
Article in English | MEDLINE | ID: mdl-15509582

ABSTRACT

In normal cells, cyclin D1 is induced by growth factors and promotes progression through the G(1) phase of the cell cycle. Cyclin D1 is also an oncogene that is thought to act primarily by bypassing the requirement for mitogens during the G(1) phase. Studies of clinical tumors have found that cyclin D1 overexpression is associated with chromosome abnormalities, although a causal effect has not been established in experimental systems. In this study, we found that transient expression of cyclin D1 in normal hepatocytes in vivo triggered dysplastic mitoses, accumulation of supernumerary centrosomes, abnormalities of the mitotic spindle, and marked chromosome changes within several days. This was associated with up-regulation of checkpoint genes p53 and p21 as well as hepatocyte apoptosis in the liver. Transient transfection of cyclin D1 also induced centrosome and mitotic spindle abnormalities in breast epithelial cells, suggesting that this may be a generalized effect. These results indicate that cyclin D1 can induce deregulation of the mitotic apparatus and aneuploidy, effects that could contribute to the role of this oncogene in malignancy.


Subject(s)
Aneuploidy , Centrosome/metabolism , Cyclin D1/genetics , Spindle Apparatus/metabolism , Animals , Cell Transformation, Neoplastic , Cells, Cultured , Cyclin D1/biosynthesis , Gene Expression Regulation , Hepatocytes/metabolism , Hepatocytes/ultrastructure , Male , Mice , Mice, Inbred BALB C , Spindle Apparatus/ultrastructure
14.
Hepatology ; 40(3): 537-44, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15349891

ABSTRACT

Following acute injuries that diminish functional liver mass, the remaining hepatocytes substantially increase overall protein synthesis to meet increased metabolic demands and to allow for compensatory liver growth. Previous studies have not clearly defined the mechanisms that promote protein synthesis in the regenerating liver. In the current study, we examined the regulation of key proteins involved in translation initiation following 70% partial hepatectomy (PH) in mice. PH promoted the assembly of eukaryotic initiation factor (eIF) 4F complexes consisting of eIF4E, eIF4G, eIF4A1, and poly-A binding protein. eIF4F complex formation after PH occurred without detectable changes in eIF4E-binding protein 1 (4E-BP1) phosphorylation or its binding eIF4E. The amount of serine 1108-phosphorylated eIF4G (but not Ser209-phosphorylated eIF4E) was induced following PH. These effects were antagonized by treatment with rapamycin, indicating that target of rapamycin (TOR) activity is required for eIF4F assembly in the regenerating liver. Rapamycin inhibited the induction of cyclin D1, a known eIF4F-sensitive gene, at the level of protein expression but not messenger RNA (mRNA) expression. In conclusion, increased translation initiation mediated by the mRNA cap-binding complex eIF4F contributes to the induction of protein synthesis during compensatory liver growth. Further study of factors that regulate translation initiation may provide insight into mechanisms that govern metabolic homeostasis and regeneration in response to liver injury.


Subject(s)
Eukaryotic Initiation Factor-4E/biosynthesis , Liver Regeneration , Liver/metabolism , Sirolimus/pharmacology , Adaptor Proteins, Signal Transducing , Animals , Carrier Proteins/metabolism , Cell Cycle Proteins , Cyclin D1/genetics , Eukaryotic Initiation Factors , Male , Mice , Mice, Inbred BALB C , Phosphoproteins/metabolism , Phosphorylation , RNA, Messenger/analysis
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