Quantitative and isomeric determination of amphetamine and methamphetamine from urine using a nonprotic elution solvent and R(-)-alpha-methoxy-alpha-trifluoromethylphenylacetic acid chloride derivatization.
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Forensic Urine Drug Testing Laboratories often requires two confirmatory methods for a methamphetamine positive screen. First, methamphetamine is identified and quantitated using gas chromatography-mass spectrometry. If the total methamphetamine concentration is above the administrative cutoff level, the isomeric composition must be determined. This eliminates a possible contribution by over-the-counter cold medications that contain l-methamphetamine (Vick's inhalers). Products that contain only the l-isomer of methamphetamine must be distinguishable from prescription or illicitly manufactured methamphetamine, which consists mainly of the d-isomer. Optically impure derivatizing reagents will produce an impure mixture from a pure isomeric compound. Therefore, methods utilizing impure reagents can prove problematic when interpreting results. Use of an optically pure chiral derivatizing reagent, such as R(-)-alpha-methoxy-alpha-trifluoromethylphenylacetic acid chloride, allows for the creation and measurement of chromatographically separable isomeric compounds. The novel method described here utilizes a polymer-based solid-phase column adapted to a positive pressure manifold extraction system and a one-step derivatization process that occurs directly in the elution solvent. This methodology eliminates an elution solvent dry-down step that may adversely affect recovery of volatile amphetamine compounds. Although the method was designed for the quantitative analysis of the isomers of amphetamine and methamphetamine, it can be adapted for use with a wide range of phenethylamines including methylenedioxyamphetamine, N-methylenedioxymethamphetamine, and possibly N-methylenedioxyethylamphetamine. The linear range for quantitation was 25-10,000 ng/mL for d,l-methamphetamine and d,l-amphetamine, and correlation coefficients were 0.997 or better. The coefficient of variation for all four analytes did not exceed 2.8%. Concentrations analyzed ranged from 500 to 4000 ng/mL (n=40). The method allows for a simple and accurate quantitation and isomeric determination of amphetamine and methamphetamine using a process that eliminates extraction and derivatization complications common in current methods. (+info)
Rapid simultaneous determination of amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, and 3,4-methylenedioxyethylamphetamine in urine by fast gas chromatography-mass spectrometry.
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The use of fast gas chromatography-mass spectrometry (FGC-MS) was investigated to improve the efficiency of analysis of urine specimens that previously screened presumptively positive for amphetamine (AMP), methamphetamine (MAMP), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), and/or 3,4 methylenedioxyethylamphetamine (MDEA) by immunoassay testing. Specimens were pretreated with basic sodium periodate, extracted using a positive-pressure manifold/cation-exchange solid-phase cartridge methodology, and derivatized using 4-carbethoxyhexafluorobutyryl chloride (4-CB). The analytical method was compared to traditional GC-MS analysis and evaluated with respect to assay chromatography, linearity, sensitivity, precision, accuracy, and reproducibility. The limits of detection were 62.5 ng/mL for MDA and 31.25 ng/mL for AMP, MAMP, MDMA, and MDEA. All of the target analytes were linear to 12,000 ng/mL with the exception of MAMP which was linear to 10,000 ng/mL. The intra-assay precision of a 500 ng/mL multiconstituent control (n=15) ranged from 522.6 to 575.9 ng/mL with a coefficient of variation of less than 3.8%. Authentic human urine specimens (n=187) previously determined to contain the target analytes were re-extracted and analyzed by both FGC-MS and the currently utilized GC-MS method. No significant differences in specimen concentration were observed between these analytical methods. No interferences were seen when the performance of the FGC-MS method was challenged with ephedrine, pseudoephedrine, phenylpropanolamine, and phentermine. When compared to traditional GC-MS analysis, FGC-MS analysis provided a dramatic reduction in retention time for amphetamine (1.8 min vs. 4.12 min). For example, the FGC-MS method reduced overall run time for a batch of 56 specimens from 12.0 h to 7.25 h. This reduction in analysis time makes FGC-MS an attractive alternative to traditional GC-MS by allowing a laboratory greater flexibility in the purchase and use of capital equipment and in the assignment of laboratory personnel, all resulting in greater overall efficiency by decreasing reporting times for AMP, MAMP, and designer amphetamine positive specimens. (+info)
National Drugs Campaign--the GP's role in reducing illicit drug use.
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BACKGROUND: According to the most recent National Drug Strategy Household Survey, almost two in every 5 Australians have used an illicit drug at some time in their life. OBJECTIVE: This article outlines the components of the second phase of the Australian Government National Drugs Campaign, launched in April 2005, and provides specific drug information on cannabis, amphetamines, and ecstasy for general practitioners. DISCUSSION: Medical practitioners play an important role as a first point of contact for parents, carers and young people. As the campaign raises awareness of the issue of illicit drugs, medical practitioners may be asked for information and advice about drugs. They may also play a wider role in identifying drug related problems, providing interventions, referrals, and coordinating care. (+info)
Methamphetamine use and HIV risk behaviors among heterosexual men--preliminary results from five northern California counties, December 2001-November 2003.
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Methamphetamine (meth) is a highly addictive stimulant that gained widespread popularity in California in the 1980s and has since spread to most regions of the United States, including rural areas. Analyses of survey data among noninjection-drug users from California in the mid-1990s determined that, among heterosexual persons and among men who had sex with men (MSM), meth users reported more sex partners, were less likely to report condom use, and were more likely to report sex in exchange for money or drugs, sex with an injection-drug user, and history of a sexually transmitted disease (STD). Subsequent studies among MSM have indicated an association between meth use and sexual risk behaviors, syphilis infection, and incidence of human immunodeficiency virus (HIV) infection. Subsequent studies among heterosexual populations have been less extensive than those among MSM and often have not used population-based samples nor adjusted for possible confounders. To further assess the association between meth use and high-risk sexual behaviors among heterosexual men, the California Department of Health Services, Office of AIDS, analyzed population-based data from five northern California counties in the HEY-Man (Health Evaluation in Young Men) Study. This report summarizes the results of that analysis, which determined that recent meth use was associated with high-risk sexual behaviors, including sex with a casual or anonymous female partner, anal intercourse, and sex with an injection-drug user. The results suggest the need for states to consider including referrals to meth prevention and treatment programs in their HIV prevention programs and for broader assessment of the relation between meth use and high-risk sexual behaviors. (+info)
Repeated amphetamine administration decreases D1 dopamine receptor-mediated inhibition of voltage-gated sodium currents in the prefrontal cortex.
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Adaptations in dopamine (DA) transmission in the prefrontal cortex (PFC) are thought to be critical to the development and persistence of drug addiction. Our previous findings showed that medial PFC (mPFC) neurons in rats treated repeatedly with amphetamine exhibit a decreased inhibitory response to iontophoretically applied DA, demonstrating altered DA receptor transmission. To determine the role postsynaptic DA D1 receptors play in this effect, we used whole-cell patch-clamp recordings of acutely dissociated pyramidal mPFC neurons and inhibition of transient voltage-sensitive sodium current (INaT) as a measure of D1 receptor function. After 3 d of withdrawal, neurons recorded from amphetamine-treated rats (5 mg/kg for 5 d) demonstrated a significant decrease in whole-cell INaT density and in the ability of D1 receptor stimulation to inhibit INaT. Application of a protein kinase A (PKA) inhibitor blocked the ability of D1 receptor activation to inhibit INaT and increased the current density of both groups to similar values. These results suggest that repeated amphetamine exposure results in subsensitivity of the INaT to D1 receptor-mediated inhibition because of a possible increase in basal PKA activity. This adaptation may contribute to perseverative behaviors in animals that self-administer psychostimulants as well as compromised PFC-dependent behaviors in human addicts. (+info)
Direct determination of p-hydroxymethamphetamine glucuronide in human urine by high-performance liquid chromatography.
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High-performance liquid chromatography (HPLC) with UV detection for the simultaneous determination of the free form of p-hydroxymethamphetamine (p-OHMA) and its metabolite, glucuronide (p-OHMAG) was accomplished for the first time. We achieved this by employing 1) an ion pair reagent for retention of sample to a solid-phase extraction (SPE) cartridge, Sep-Pak Light C18 and 2) a simple two-step stepwise elution technique for subsequent ion pair RP-HPLC. The proposed method was optimized for resolution of p-OHMAG, p-OHMA and MA. The method was successfully applied to urine samples collected from MA abusers. (+info)
Differences in club drug use between heterosexual and lesbian/bisexual females.
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Although there has been much empirical research documenting current trends in club drug use among gay and bisexual men, little research has addressed the variance among lesbian, bisexual, or heterosexual women. Using data collected through time-space sampling from dance clubs in New York City during 2005 (N=1104), this study explored sexual identity variance among women in the reported use of six club drugs: methamphetamine, cocaine, MDMA, ketamine, GHB, and LSD. Significant differences were found in that younger women were more likely to be active club drug users. Lesbian and bisexual women reported significantly higher lifetime rates of ecstasy, cocaine, methamphetamine, and LSD use compared to heterosexual women. These data suggest a need to better understand the influence of sexual orientation and sexual culture in relation to club drug use and to tailor health promotion efforts to meet the needs of various groups of club drug using women. (+info)
Methamphetamine-induced cell death: selective vulnerability in neuronal subpopulations of the striatum in mice.
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Methamphetamine (METH) is an illicit and potent psychostimulant, which acts as an indirect dopamine agonist. In the striatum, METH has been shown to cause long lasting neurotoxic damage to dopaminergic nerve terminals and recently, the degeneration and death of striatal cells. The present study was undertaken to identify the type of striatal neurons that undergo apoptosis after METH. Male mice received a single high dose of METH (30 mg/kg, i.p.) and were killed 24 h later. To demonstrate that METH induces apoptosis in neurons, we combined terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining with immunohistofluorescence for the neuronal marker neuron-specific nuclear protein (NeuN). Staining for TUNEL and NeuN was colocalized throughout the striatum. METH induces apoptosis in approximately 25% of striatal neurons. Cell counts of TUNEL-positive neurons in the dorsomedial, ventromedial, dorsolateral and ventrolateral quadrants of the striatum did not reveal anatomical preference. The type of striatal neuron undergoing cell death was determined by combining TUNEL with immunohistofluorescence for selective markers of striatal neurons: dopamine- and cAMP-regulated phosphoprotein, of apparent Mr 32,000, parvalbumin, choline acetyltransferase and somatostatin (SST). METH induces apoptosis in approximately 21% of dopamine- and cAMP-regulated phosphoprotein, of apparent Mr 32,000-positive neurons (projection neurons), 45% of GABA-parvalbumin-positive neurons in the dorsal striatum, and 29% of cholinergic neurons in the dorsal-medial striatum. In contrast, the SST-positive interneurons were refractory to METH-induced apoptosis. Finally, the amount of cell loss determined with Nissl staining correlated with the amount of TUNEL staining in the striatum of METH-treated animals. In conclusion, some of the striatal projection neurons and the GABA-parvalbumin and cholinergic interneurons were removed by apoptosis in the aftermath of METH. This imbalance in the populations of striatal neurons may lead to functional abnormalities in the output and processing of neural information in this part of the brain. (+info)