Using strain to uncover the interplay between two- and three-dimensional charge density waves in high-temperature superconducting YBa2Cu3Oy.

Uniaxial pressure provides an efficient approach to control charge density waves in YBa2Cu3Oy. It can enhance the correlation volume of ubiquitous short-range two-dimensional charge-density-wave correlations, and induces a long-range three-dimensional charge density wave, otherwise only accessible at large magnetic fields. Here, we use x-ray diffraction to study the strain dependence of these charge density waves and uncover direct evidence for a form of competition between them. We show that this interplay is qualitatively described by including strain effects in a nonlinear sigma model of competing superconducting and charge-density-wave orders. Our analysis suggests that strain stabilizes the 3D charge density wave in the regions between disorder-pinned domains of 2D charge density waves, and that the two orders compete at the boundaries of these domains. No signatures of discommensurations nor of pair density waves are observed. From a broader perspective, our results underscore the potential of strain tuning as a powerful tool for probing competing orders in quantum materials.

Alternative specimens for workplace drug testing.

Recent advances in analytical techniques have enabled the detection of drugs and drug metabolites in alternative biological specimens for the purposes of workplace testing. A wide variety of specimens are available, each providing valuable information concerning prior or current drug use. The present focus is on oral fluid (saliva), hair, and sweat. An extensive evaluation by the Division of Workplace Programs of the Department of Health and Human Services is underway to determine the utility of these specimens in federally regulated programs. In future years, the testing of alternative specimens will expand our ability to understand the patterns of drug use and will become routine in all areas of forensic toxicology.

The characterization of human urine for specimen validity determination in workplace drug testing: a review.

One challenge facing the laboratory forensic toxicologist today is verifying the validity of the random urine specimen submitted for workplace drugs of abuse analysis. Determining whether urine substitution has occurred is best accomplished through the inspection of the specimen's appearance and the performance of specific laboratory tests, such as determining the concentration of biochemical metabolic waste products and measuring indices of urine concentration. Criteria for classifying submitted urine as substituted are postulated after an extensive review of the published scientific literature. Relevant studies that were evaluated include normal random urine reference interval studies, clinical studies involving the analysis of random urine specimens, theoretical dilutional limits, medical conditions resulting in overhydration, and water-loading studies. After compilation of the study data, derived substituted criteria of urinary creatinine < or = 5.0 mg/dL and urinary specific gravity < or = 1.001 are suggested. A urine specimen meeting these criteria may be considered substituted because it is not consistent with the clinical characteristics associated with normal human urine.

Detection of methadone, methadone metabolites, and other illicit drugs of abuse in hair of methadone-treatment subjects.

The disposition of methadone, its metabolites, and other illicit drugs of abuse was investigated in head hair samples collected from heroin users (N = 20) enrolled in an outpatient detoxification study. Hair samples were assayed for methadone, methadone primary metabolite (2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine, EDDP), methadone secondary metabolite (2-ethyl-5-methyl-3,3-diphenylpyrroline, EMDP), cocaine, phencyclidine, heroin, and 6-acetylmorphine. Hair samples were cut, washed, and incubated in methanol. The methanolic hair wash and incubation fractions were purified with solid-phase extraction and assayed by gas chromatography-mass spectrometry. Methadone, methadone metabolites, cocaine, and phencyclidine were assayed quantitatively, and other drugs were measured qualitatively. The number of positive results and the corresponding concentration ranges were as follows: methadone, 0-15.0 ng/mg (N = 18); EDDP, trace (N = 13); EMDP, trace (N = 1); cocaine, 0->40 ng/mg (N = 14); phencyclidine, 0-1.5 ng/mg (N = 2); heroin, positive (N = 3); and 6-acetylmorphine, positive (N = 4). These data suggest that testing hair for methadone, methadone metabolites, and other illicit drugs of abuse may be useful to drug-treatment specialists as a means of verifying drug-use history, monitoring compliance, and providing a broad measure of drug exposure.

The storage of forensic urine drug specimens as dry stains: recovery and stability.

The feasibility of storing forensic urine drug specimens as dry stains on Whatman #3 paper was studied by evaluating the stability of the drugs and recovery from the stains. Drug stains prepared from urine (3 mL) were stores at -20 degrees C, 4 degrees C, and at room temperature for a period of 12 weeks. The study included: amphetamine, benzoylecgonine, 11-nor-delta-9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH), morphine, and phencyclidine (PCP) as examples of the HHS regulated drug classes. Drugs were eluted from the stains as follows: methanol:saline (1:1) for PCP and THC-COOH, saline for benzoylecgonine and carbonate/bicarbonate buffer pH 9.2 for amphetamine and morphine. Stains were eluted from the support matrix (Whatman #3 filter paper), extracted and analyzed by gas chromatography/mass spectrometry. All drugs were stable under all of the storage conditions except the THC-COOH urine stain stored at room temperature that degraded to zero after 12 weeks. Therefore, drug stains when kept frozen or refrigerated appear to provide a viable means for storing positive urine specimens.

Fluoxetine and violent death in Maryland.

A retrospective Medical Examiner case review of all deaths in Maryland where either fluoxetine or tricyclic antidepressant (TCA) use was forensically detected was conducted for the time period January 1987-July 1991. Case records and toxicology reports from the Office of the Chief Medical Examiner were reviewed to determine cause and manner of death, circumstances of death, demographic information on the decedent, prior medical history of the decedent, and presence and level of either fluoxetine or TCA in various body fluids/tissues. Suicide was the manner of death most frequently associated with TCA and fluoxetine detection. Violent methods were more often associated with fluoxetine suicides than with TCA suicides (65% v. 23%, P < 0.001). Demographic characteristics of antidepressant-related deaths in Maryland were similar to those of the entire USA. Possible explanations for the results obtained include the inherent lower lethality of fluoxetine compared to the TCAs, necessitating the use of additional means to complete the act of suicide; that physicians may have switched more impulsive, high risk patients to this new agent as it became available, thus creating a selection bias for more violence-prone individuals in the fluoxetine group; or that fluoxetine may be associated with induction of violence and/or suicidal ideation. Further research examining the possible association of these agents with violent acts is warranted.

Disposition of heroin and its metabolites in heroin-related deaths.

Although many deaths occur annually from heroin intoxication, the presence of heroin has not been reported in postmortem tissues. Recognizing heroin's susceptibility to rapid chemical and metabolic hydrolysis, extraction procedures were developed for the efficient recovery of heroin, 6-acetylmorphine, and morphine from postmortem tissue utilizing solid-phase extraction coupled with gas chromatography/mass spectrometry. From heroin-related deaths, 21 sets of blood and urine specimens were collected. The mode of death in these cases was categorized as rapid, delayed, or undetermined. Compared with delayed deaths, rapid deaths were characterized by the following trends: higher mean concentrations of 6-acetylmorphine, free morphine, and total opiates in blood; a higher ratio of free morphine concentrations to total opiate concentrations in blood; lower mean concentrations of 6-acetylmorphine and morphine in urine; greater likelihood of 6-acetylmorphine detection in blood; and lesser likelihood of heroin detection in urine. The study also included analysis of multiple tissue specimens from two subjects who died of heroin intoxication. Heroin was identified in urine and injection-site tissue. Concentrations of 6-acetylmorphine in cerebrospinal fluid, spleen, and brain were substantially higher than in blood, liver, lung, and kidney. All specimens were positive for morphine. Heroin metabolites were detected in hair specimens. The identification of heroin and 6-acetylmorphine in biological tissues effectively established the presence of heroin in cases of acute narcotic intoxication. These studies demonstrated that measurement of heroin and its metabolites provides useful information for the differential diagnosis of heroin-related deaths.

Interpretation of low postmortem concentrations of ethanol.

The interpretation of postmortem blood ethanol concentrations (BAC), especially those less than 0.05 g/dL can be complicated by postmortem ethanol formation. One method used by the toxicologist to respond to this possibility is to analyze multiple specimens for ethanol. Two useful specimens to analyze are vitreous humor and urine, because they are less susceptible to the putrefaction process. A negative vitreous humor and/or urine ethanol would suggest that the measured ethanol resulted from postmortem formation. Data were collected from the Office of the Chief Medical Examiner, State of Maryland and the Armed Forces Institute of Pathology on blood specimens with ethanol concentrations less than 0.05 g/dL to develop a reasonable threshold for interpretation in the absence of other specimens. A total of 381 cases with a BAC between 0.01 and 0.04 g/dL were studied over a 2 year period. Urine and vitreous humor specimens were tested where available. At a BAC of 0.01 g/dL, 54% of the cases were associated with a positive vitreous humor and/or urine ethanol concentration. This percentage increased to 63% when BAC equals 0.02 g/dL. Seventy-three percent and 92% of the cases had a positive alternate specimen if the BAC was 0.03 g/dL and 0.04 g/dL, respectively. In addition, 90% of the cases where both vitreous humor and urine were analyzed showed consistent results, that is both specimens were positive or negative. This suggests that in the absence of additional information, a BAC of 0.04 g/dL or higher probably resulted from ethanol consumption.

Measurement of heroin and its metabolites by isotope-dilution electron-impact mass spectrometry.

A solid-phase extraction procedure was developed for the isolation of heroin, 6-acetylmorphine, and morphine from blood, plasma, saliva, and urine with subsequent assay by gas chromatography/mass spectrometry. Aprotic solvents, mild elution conditions, and an enzyme inhibitor were used to ensure maximum analyte stability. Samples were extracted and the extract was divided into two equal portions. One portion was assayed directly for heroin; detector response was linear over a concentration range of 1.0 to 250 micrograms/L. The second part of the extract was reacted with N-methyl-bis-trifluoroacetamide and assayed for the trifluoroacetyl derivatives of 6-acetylmorphine and morphine; detector response was linear over a concentration range of 1.0 to 500 micrograms/L. The limit of sensitivity was 1.0 microgram/L for each analyte. Hydrolysis of heroin to 6-acetylmorphine during extraction and analysis was < 5%. The method can be used to corroborate heroin use and to study the pharmacological effects of heroin and its metabolites.

Serial capillary gas chromatography/Fourier transform infrared spectrometry/mass spectrometry (GC/IR/MS): qualitative and quantitative analysis of amphetamine, methamphetamine, and related analogues in human urine.

A method using serial capillary gas chromatography/Fourier transform infrared spectroscopy/mass spectrometry (GC/IR/MS) for the analysis of derivatized amphetamine, methamphetamine, and related analogues was developed. The GC/IR/MS was configured and optimized with a Hewlett-Packard (HP) 5890A gas chromatograph with a 12-m x 0.32-mm i.d. HP-5 capillary column serially interfaced through an HP 5965A infrared detector to an HP 5970 mass selective detector with a fused-silica 1.2-m x 0.10-mm i.d. column. Urine samples are extracted and derivatized as heptafluorobutyryl (HFBA) derivatives. For quantitation GC/MS in the selected ion monitoring (SIM) mode was used, with D,L-amphetamine-D5 as the internal standard. Gas chromatography/Fourier transform infrared spectrometry (GC/FT-IR) quantitation uses a selected wavelength chromatogram, spectral subtraction, double internal standard method using both D,L-amphetamine-D5 and 4-phenyl butylamine. Sensitivity for the combined GC/MS and GC/FT-IR system for amphetamine and methamphetamine shows limits of linearity of 100 to 5000 ng/mL, a limit of detection of 25 ng/mL, and a limit of quantitation of 98 ng/mL. The overall recovery for amphetamine and related analogues was greater than 85%. Precision studies for concentrations over the range of 200 to 1500 ng/mL showed coefficients of variations ranging from 2.8 to 13.0%. Correlation studies for quantitative GC/MS SIM and GC/FT-IR are greater than 0.98 for amphetamine, methamphetamine, and related analogues. Each analysis includes GC/MS SIM and GC/FT-IR quantitation, qualitative nonselective full spectra GC/FT-IR, and GC/MS scans of HFBA derivatives cross-referenced with an internal drug library, which provides high confidence and a means for the surveillance of amphetamine-like chemical analogues.

Bupropion and alcohol fatal intoxication: case report.

A fatality due to the ingestion of bupropion and ethanol is presented. Bupropion and its metabolites were extracted from several tissues and identified using gas chromatography with nitrogenphosphorus and mass spectrometry detection. The concentrations of bupropion, hydroxybupropion and the erythroamino and threoamino alcohol metabolites in heart blood were 4.2, 5.0, 0.6 and 4.6 mg/l, respectively. The heart blood ethanol concentration was 0.27 g/dl. In addition, bupropion was distributed as follows: subclavian blood, 6.2 mg/l; bile, 1.4 mg/l; kidney, 2.4 mg/l; liver, 1.0 mg/kg; stomach contents, 16 mg and urine, 37 mg/l.

Concentration of cocaine and metabolites in plasma of humans following intravenous administration and smoking of cocaine.

Plasma was obtained from 10 human subjects at various intervals after administration of two rapid doses of cocaine, either intravenously or by smoking, and multiple doses by smoking and intravenously. The plasma was analyzed for COC and its metabolites, benzoylecgonine (BE) and ecgonine methyl ester (EME). Plasma concentrations of COC were found to be dose-dependent. For patients receiving two successive doses of COC intravenously (IV) or by smoking (SM), the average half-life of COC was found to be between 38 and 39 minutes, regardless of the dose or route of administration. Considerable interindividual variation was observed. Multiple doses of both SM and IV COC were administered to three patients in a manner consistent with COC abuse. The maximum COC concentration observed was 1.2 mg/L following a total administration of 316 mg of COC over 90 min. Analysis of BE and EME confirmed that BE is the principle metabolite of COC in blood. All COC was accounted for by BE. EME, when present, did not exceed 5% of the BE concentration.

Detection of cocaine and its metabolites in human amniotic fluid.

The dramatic rise in maternal drug abuse and the incidence of positive drug findings during neonatal testing has increased the need for prenatal toxicological testing for drugs of abuse. Human amniotic fluid samples collected after 13-39 weeks of pregnancy were screened for cocaine metabolite (benzoylecgonine) by fluorescence polarization immunoassay (FPIA). All positive samples, as well as any accompanying maternal serum, were confirmed by gas chromatography/mass spectrometry (GC/MS) for cocaine and its metabolites. Five samples out of 450 were positive for cocaine, benzoylecgonine, and ecgonine methyl ester by GC/MS. In addition, one sample was also positive for cocaethylene. Two maternal serum samples were positive for benzoylecgonine and ecgonine methyl ester. The presence of cocaine, benzoylecgonine, ecgonine methyl ester, and cocaethylene in the amniotic fluid suggests that the fetus is exposed to cocaine and its metabolites through maternal circulation. The impact of this exposure on the health of the newborn is unknown.

The role of ecgonine methyl ester in the interpretation of cocaine concentrations in postmortem blood.

A study of the metabolism of in vivo cocaine (COC) and the stability of in vitro COC suggests that the presence of benzoylecgonine (BE) in unpreserved blood arises from in vivo COC metabolism and that ecgonine methyl ester (EME) in unpreserved blood arises from in vitro COC hydrolysis. Postmortem cases positive for COC were studied to determine if molar concentrations of EME in unpreserved blood could be used to estimate the blood COC concentration at the time of death when added to the molar COC concentrations. COC was analyzed in 10 postmortem blood specimens between 1 and 8 days following death and again 10 to 70 days after further storage. The COC lost was accounted for by its hydrolysis to EME. Good correlation (r = 0.9677, p < 0.001) was observed when the blood COC concentrations in postmortem cases were compared to blood COC concentrations predicted by the addition of blood COC and EME concentrations; hence, analysis for EME and estimation of perimortem COC concentrations can assist in defining deaths associated with COC use.

Chloral hydrate overdose: trichloroethanol detection by gas chromatography/mass spectrometry.

A case is presented where an individual ingested a fatal dose of chloral hydrate. Trichloroethanol (TCE), the metabolite of chloral hydrate, was initially identified by the Fujiwara reaction and quantified by gas chromatography/mass spectrometry in blood )127 mg/l), urine (128 mg/l) and stomach contents (25 mg total).

Analysis of spleen specimens for carbon monoxide.

Crucial to the investigation of aircraft fatalities is the analysis of biological specimens for carbon monoxide (CO). In many cases, blood specimens are unavailable or unsuitable for analysis, and the testing of an alternate specimen for CO becomes necessary. Spleen specimens provide a rich source of red blood cells and hence can be a primary substitute for blood. To verify this, 40 paired blood and spleen specimens were analyzed for CO by using a gas chromatographic method. Ten specimens with a spleen CO saturation level (sat.) of less than 10% were associated with corresponding blood specimens with CO sat. less than 10%. Fifteen of the 18 spleen specimens with CO sat. greater than 29% were associated with blood specimens with greater than 48% sat. Results were inconclusive when the spleen CO sat. was between 10 and 29%. We concluded that spleen CO sat. can reflect blood CO sat. in certain situations, particularly when spleen CO sat. is high.

Distribution of isoniazid in an overdose death.

A fatality due to the ingestion of isoniazid, a tuberculostatic agent, is presented. Isoniazid was extracted by a single step extraction procedure, derivatized with trifluoroacetic anhydride, and identified and quantified by gas chromatography/mass spectrometry (GC/MS). The distribution of isoniazid was as follows: heart blood 43 mg/L, subclavian blood 94 mg/L, urine 470 mg/L, bile 900 mg/L, liver 650 mg/Kg, kidney 110 mg/Kg, and stomach contents 4 mg.

Testing human hair for drugs of abuse. III. Identification of heroin and 6-acetylmorphine as indicators of heroin use.

Hair samples from 20 documented heroin users contained 6-acetylmorphine, a unique metabolite of heroin, in all samples. Heroin was identified in smaller amounts in seven of these samples. The identity of 6-acetylmorphine and heroin was established by comparison of full scan spectra of extracts to standard reference materials. The presence of 6-acetylmorphine generally predominated over heroin, morphine, and codeine. The mean concentrations of analytes were as follows: 6-acetylmorphine, 0.90 ng/mg, N = 20; heroin, 0.17 ng/mg, N = 7; morphine, 0.26 ng/mg, N = 20; codeine, 0.18 ng/mg, N = 15. Analysis of hair samples obtained from 10 drug-free control subjects were negative for 6-acetylmorphine, morphine, and codeine. However, a small interfering peak was observed at the retention time for heroin. Control samples soaked in aqueous solutions of heroin and 6-acetylmorphine were found to be contaminated, even though an initial wash step was included in the analysis. These data suggest that hair analysis for 6-acetylmorphine can be used to differentiate heroin users from other types of opiate exposure (e.g., poppy seed, licit morphine, and codeine); however, environmental contamination can potentially produce false positives during opiate testing.

Two fatalities involving haloperidol.

Two cases are presented in which haloperidol was identified in postmortem toxicological analysis. One case was a suicidal overdose of the drug; the blood concentrations of haloperidol and reduced haloperidol were 1.9 and 1.4 mg/L, respectively. Bile, liver, and urine concentrations were 3.4 mg/L, 44 mg/Kg and 6.6 mg/L for haloperidol and 1.6 mg/L, 43 mg/Kg, and 5.7 mg/L for reduced haloperidol, respectively. The second case was believed to be a natural cardiac death with a blood haloperidol concentration of 0.6 mg/L. The distribution of haloperidol and reduced haloperidol in this case was bile, 0.4 and 0.5 mg/L; kidney, 0.7 and 2.3 mg/Kg; liver, 5.0 and 13 mg/Kg; and urine, 0.4 and 2.3 mg/L.