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Hurley J.M.,University of Utah | Hurley J.M.,Sports Medicine Research and Testing Laboratory | West J.B.,University of Utah | West J.B.,Texas AgriLife Research Center | Ehleringer J.R.,University of Utah
International Journal of Drug Policy | Year: 2010

Background: Although cannabis is the most readily available and widely used illicit drug in the United States, there remains significant uncertainty about the importance of different production regions and trafficking patterns. Methods: We analysed 628 " retail" cannabis seizures from over 50 municipalities across the United States for hydrogen and carbon isotope ratios to predict their growth locations and environments. Results: Results are presented for 22 consolidated retail locations across the United States. Evaluation of specimens from within these retail areas suggested that cannabis seizures had region-dependent origins, often from both domestic and foreign sources, and although indoor growth was common in many areas, there was also regional dependence in the proportions cultivated under indoor versus outdoor conditions. Conclusion: Street-available cannabis exhibits region-specific trafficking patterns, both Mexican- and Canadian-grown cannabis are apparently widely available, and indoor-grown cannabis appears to be cultivated and trafficked in both warm and cool weather localities throughout the United States. © 2009 Elsevier B.V.

Cox H.D.,Sports Medicine Research and Testing Laboratory | Lopes F.,Kings College London | Woldemariam G.A.,University of California at Los Angeles | Becker J.O.,University of Washington | And 7 more authors.
Clinical Chemistry | Year: 2014

BACKGROUND: Insulin-like growth factor 1 (IGF-1)7 is a key mediator of growth hormone (GH) action and a well-characterized biomarker of GH abuse. Current immunoassays for IGF-1 suffer from poor concordance between platforms, which makes comparison of results between laboratories difficult. Although previous work has demonstrated good interlaboratory imprecision of LC-MS/MS methods when plasma is supplemented with purified proteins, the interlaboratory imprecision of an endogenous protein in the nanogram-per- milliliter concentration range has not been reported. METHODS: We deployed an LC-MS/MS method to quantify serum IGF-1 in 5 laboratories using 5 different instruments and analyzed 130 healthy human samples and 22 samples from patients with acromegaly. We determined measurement imprecision (CV) for differences due to instrumentation, calibration curve construction, method of calibration, and reference material. RESULTS: Instrument-dependent variation, exclusive of digestion, across 5 different instrument platforms was determined to be 5.6%. Interlaboratory variation was strongly dependent on calibration. Calibration materials from a single laboratory resulted in less variation than materials made in individual laboratories (CV 5.2% vs 12.8%, respectively). The mean imprecision for 152 samples between the 5 laboratories was 16.0% when a calibration curve was made in each laboratory and 11.1% when a single-point calibration approach was used. CONCLUSIONS: The interlaboratory imprecision of serum IGF-1 concentrations is acceptable for use of the assay in antidoping laboratories and in standardizing results across clinical laboratories. The primary source of variability is not derived from the sample preparation but from the method of calibration. © 2013 American Association for Clinical Chemistry.

Cox H.D.,Sports Medicine Research and Testing Laboratory | Smeal S.J.,Sports Medicine Research and Testing Laboratory | Hughes C.M.,Sports Medicine Research and Testing Laboratory | Cox J.E.,University of Utah | Eichner D.,Sports Medicine Research and Testing Laboratory
Drug Testing and Analysis | Year: 2015

AOD9604 is a peptide consisting of the C-terminal fragment of human growth hormone from amino acids 177-191 with an additional tyrosine residue at the N-terminus of the peptide. It is reported to mimic the lipolytic properties of growth hormone without the diabetogenic side effects. Therefore, AOD9604 may be used as a performance enhancing drug and is banned by the World Anti-doping Agency (WADA). The peptide is available on several Internet websites and was recently identified in confiscated vials in the USA. To detect abuse of the peptide in athletes, a solid-phase extraction method was validated in urine with a limit of detection of 50pg/mL. The method has good linearity, precision (<20%), specificity and recovery (62%). Six potential metabolites of the peptide were identified after incubation of AOD9604 in serum and urine. Quantification of the metabolites in serum identified a single metabolite, consisting of amino acids CRSVEGSCG, which is significantly more stable than the other metabolites or the parent compound. Screening for AOD9604 and the stable metabolite may potentially allow an increased window of detection. © 2014 John Wiley & Sons, Ltd.

Van Wagoner R.M.,Sports Medicine Research and Testing Laboratory | Satake M.,University of Tokyo | Wright J.L.C.,University of North Carolina at Wilmington
Natural Product Reports | Year: 2014

Covering: up to 2013 Dinoflagellates produce unique polyketides characterized by their size and complexity. The biosynthesis of a limited number of such metabolites has been reported, with studies largely hampered by the low yield of compounds and the severe scrambling of label in the isotopically-labeled precursors. Nonetheless, of the successful biosynthetic experiments that have been reported, many surprising and unique processes have been discovered. This knowledge has been accessed through a series of biochemical labeling studies, and while limited molecular genetic data has been amassed, it is still in the early stages of development. In an attempt to meet this challenge, this review has compared some of the biosynthetic processes with similar ones identified in other microbes such as bacteria and myxobacteria, with the idea that similar genes and enzymes are employed by dinoflagellates. This journal is © the Partner Organisations 2014.

Cox H.D.,Sports Medicine Research and Testing Laboratory | Eichner D.,Sports Medicine Research and Testing Laboratory
Rapid Communications in Mass Spectrometry | Year: 2013

RATIONALE Reported incidents of the use of nutritional supplements containing deer antler velvet by athletes has increased significantly in recent years. The supplements have been reported to contain insulin-like growth factor-1 (IGF-1), which is a banned substance included on the World Anti-Doping Agency (WADA) prohibited list. The presence of deer and human IGF-1 was tested in six commercially available supplements. METHODS IGF-1 was extracted from the six deer antler velvet supplements using chloroform and acetonitrile precipitation methods. Ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) methods were developed to measure intact IGF-1 protein and IGF-1 trypsin peptides using a triple quadrupole mass spectrometer. Five deer-specific and five human-specific multiple-reaction monitoring (MRM) transitions for intact IGF-1were measured as well as six deer-specific and seven human-specific MRM transitions for an IGF-1 trypsin peptide. RESULTS The peak area from each MRM transition was used to calculate the product ion ratios relative to the most abundant transition. Product ion ratios measured in the supplements were matched to ratios measured in purified protein standards. A match to human IGF-1 was identified for all the MRM transitions measured in four of the supplements tested. CONCLUSIONS The presence of a pharmaceutical protein, human IGF-1, was confirmed in four commercially available products sold as all natural, nutritional supplements. These methods can be used to screen additional products to further prevent the illegal sale of adulterated supplements. Copyright © 2013 John Wiley & Sons, Ltd.

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