Biomedical subjects

B D Paul

Publications and source records attributed to B D Paul.

At least 19 recordsLinked to original sources

PubMed2001

Urinary excretion profiles for total morphine, free morphine, and 6-acetylmorphine following smoked and intravenous heroin.

Heroin is one of the major target drugs in workplace drug-testing programs because of its history of abuse, liability, and continued negative social impact. This study was a comprehensive examination of pharmacokinetics, pharmacodynamics, detection times, opiate immunoassay performance, and urine excretion profiles following single doses of heroin administered to human subjects via smoking and intravenous routes. Studies of the first four components of this investigation were previously published. This article describes the urine excretion profiles. Total morphine (Tmor), free morphine (Fmor), and 6-acetylmorphine (6-AM) were measured by gas chromatography-mass spectrometry (GC-MS) in 920 urine samples collected from 11 male human subjects following single doses of heroin. Eight received intravenous doses of 3, 6, and 12 mg heroin HCI and four smoked 3.5-, 5.2-, 7-, 10.5-, or 13.9-mg doses of heroin (base). In addition, 183 urine-based blind quality-control samples were added to the study set to assess assay performance. Creatinine was also measured in each sample by a colorimetric technique. The parameters studied were not significantly dependent on route of administration. Excretion half-life mean +/- SD for Tmor was 3.11 +/- 0.30 h. Range (median) of peak urine concentrations, time to peak, time to last positive sample for low cutoff (300 ng/mL) and high cutoff (2000 ng/mL) for Tmor following lower doses (< or = 7 mg) were, respectively, 1392-9250 (3620) ng/mL, 1.2-6.2 (2.3) h, 7.4-31.9 (7.4) h, and 0-10.1 (4.3) h. Following higher doses (> 10 mg) they were 2065-29,030 (16,470) ng/mL, 2.3-9.3 (4.5) h, 10.7-53.5 (34.4) h, 2.3-22.3 (8.3) h. Fmor peaked in the same sample as Tmor. Range (median) of peak Fmor concentrations and time to last positive using a cutoff of 100 ng/mL for low and high doses were, respectively, 117-1160 (415) ng/mL, 1.2-10.1 (4.5) h and 150-2580 (1400) ng/mL, 2.3-29.1 (9.3) h. The range (median) of peak urine concentrations for 6-AM was 6.1-568 (124) ng/mL. In general, the first urine void had the peak 6-AM concentration and was the only specimen positive at a 10-ng/mL cutoff. As previously reported urine concentrations varied greatly between subjects and within subjects with time after dosing but were much more predictable when values were reported as amount of drug per unit of creatinine. The range (median) values for percent of heroin excreted into urine as Tmor was 12.8-88.5% (51.0).

Administration, Inhalation↗

PubMed2001

Cathinone (Khat) and methcathinone (CAT) in urine specimens: a gas chromatographic-mass spectrometric detection procedure.

A gas chromatographic-mass spectrometric procedure for detection of cathinone (Khat) and methcathinone (CAT) in urine was developed. The compounds were detected as 4-carboethoxyhexafluorobutyryl derivatives. Three ions for the drugs and two ions for the internal standards were monitored. The drugs were identified by comparing retention times and ion ratios with that of reference compounds. The concentrations were measured by using amphetamine-d6 as internal standard for cathinone and methamphetamine-d9 as internal standard for methcathinone, and were linear over the range of 25-5000 ng/mL for cathinone and 12.5-5000 ng/mL for methcathinone. The overall recoveries of cathinone and methcathinone were 86 and 78%, respectively. Intrarun and inter-run variations were < 20%. To verify that the drugs are not metabolites of over-the-counter medications, cathinone and methcathinone were tested in urine specimens collected from individuals who ingested phenylpropanolamine and pseudoephedrine. None of the specimens showed the keto-amines as the metabolic products. When the procedure was applied to test 66 amphetamine-immunoassay-positive specimens containing no amphetamine or methamphetamine, two specimens were found positive for cathinone (118 and 3266 ng/mL) and six specimens were found positive for methcathinone (13-91 ng/mL).

Alkaloids↗

PubMed2001

Examination of postmortem fluids and tissues for the presence of methylecgonidine, ecgonidine, cocaine, and benzoylecgonine using solid-phase extraction and gas chromatography-mass spectrometry.

BACKGROUND: During the smoking of crack cocaine (COC), methyl ecgonidine (MED) is formed as one of the pyrolysis products. Once in the body, MED is converted to ecgonidine (ED) through several processes that include spontaneous hydrolysis and enzymatic hydrolysis. The presence of MED and/or ED could provide valuable information to help determine antemortem conditions in cases where COC is involved. Our goal was to examine postmortem tissues and fluids for the presence of MED, ED, COC, and benzoylecgonine (BZ). METHODS: Liver, brain, blood, and urine specimens obtained from 15 postmortem cases were extracted using solid-phase extraction, derivatized, and analyzed using gas chromatography-mass spectrometry with selective-ion monitoring. RESULTS: Median concentrations (range) of drugs observed in postmortem liver, brain, blood, and urine were 0 (0-10) ng/g, 7 (0-92) ng/g, 0 (0-42) microg/L, and 62 (0-2030) microg/L, respectively, for MED; 655 (90-3274) ng/g, 22 (0-52) ng/g, 119 (13-773) microg/L, and 456 (109-7452) microg/L, respectively, for ED; 57 (0-503) ng/g, 187 (0-1403) ng/g, 12 (0-88) microg/L, and 1208 (37-28 062) microg/L, respectively, for COC; and 821 (45-4980) ng/g, 524 (46-5153) ng/g, 458 (30-2071) microg/L, and 6768 (917-116 430) microg/L, respectively, for BZ. MED was detected in 12 of 15 postmortem cases. The concentrations were highest in urine compared with liver, brain, and blood. The hydrolysis product ED was detected in all postmortem cases, and the concentrations were substantially higher than MED in all liver, blood, and urine specimens. CONCLUSION: ED may be a more useful indicator of crack COC smoking.

Body Fluids↗

PubMed2000

Detection times and analytical performance of commercial urine opiate immunoassays following heroin administration.

The Federal Workplace Drug Testing Program changed urine screening and confirmation cutoff concentrations for opiate testing from 300 to 2000 ng/mL in 1998. Morphine was the designated target compound. An additional heroin metabolite, 6-acetylmorphine (6-AM), was added to the testing procedure with a cutoff concentration > or = 10 ng/mL. Testing of 6-AM was required if morphine was positive to assist in medical review. A comparison of the new opiate cutoff concentrations was made with the older cutoff concentration at 300 ng/mL. Six commercial opiate immunoassays, four with a 300-ng/mL cutoff, ONLINE, EMIT, CEDIA and AxSym, and two with 2000-ng/mL cutoffs, ONLINE and EMIT, were selected to test 920 urine samples collected from 11 male human subjects following single doses of heroin. Eight received intravenous doses of 3, 6, and 12 mg heroin HCl and four smoked 3.5-, 5.2-, 10.5-, or 13.9-mg doses of heroin (base). In addition, 183 urine-based blind quality-control specimens were added to the study set to assess linearity, cross-reactivity, and interference. Total morphine, free morphine, and 6-AM were measured in each sample by gas chromatography-mass spectrometry (GC-MS). Linearity, cross-reactivity, and interference results for each immunoassay are described. Detection times, sensitivity, specificity, and efficiency of each assay were determined using data from the specimens collected after heroin administration. Detection times for morphine using the 300-ng/mL cutoff assays was approximately 12 h for low dose and 24 to 48 h for higher doses of heroin. For the two 2000-ng/mL cutoff concentration assays detection time was about 12 h. This was also the detection time for 6-AM by GC-MS. ONLINE had the lowest sensitivity, 60-74%, highest specificity, 98.8-100%, and least interference from a selection of common over-the-counter drugs and opioids. Increasing the cutoff to 2000 ng/mL from 300 ng/mL increased efficiencies of the assays from 72.7 to 82.6% to over 97%.

Administration, Inhalation↗

PubMed1999

Electron ionization mass fragmentometric detection of urinary ecgonidine, a hydrolytic product of methylecgonidine, as an indicator of smoking cocaine.

When cocaine is smoked, methylecgonidine (anhydroecgonine methyl ester) is also consumed as a pyrolytic product. Methylecgonidine, on incubation with human liver homogenate, was metabolized to a stable compound, ecgonidine. The compound was also formed when methylecgonidine was exposed to a urine pH > or = 8.0. Ecgonidine is a zwitterion and highly water soluble. A method was developed to identify ecgonidine quantitatively in urine. After removal of cocaine, benzoylecgonine and methylecgonidine from urine at pH 5.5 +/- 0.5 using a solid-phase extraction (SPE) technique, the pH of the solution was readjusted to 2.0-3.0. The acidic solution reduced the dissociation of the carboxylic acid and improved the lipophilic and cationic character of ecgonidine. The compound was extracted from the solution with the SPE technique with an 89-99% yield. Ecgonidine was then detected as a tert-butyldimethylsilyl derivative by a gas chromatographic/electron ionization mass spectrometric method. Quantitation was linear over the concentration range 7-2000 ng ml-1. Concentrations as low as 7 ng ml-1 can be detected by this procedure. Ecgonidine was detected in > 95% of benzoylecgonine-positive urine specimens from a random drug testing program, indicating smoking as the major route of cocaine administration.

Cocaine↗

PubMed1999

A practical approach to determine cutoff concentrations for opiate testing with simultaneous detection of codeine, morphine, and 6-acetylmorphine in urine.

BACKGROUND: Both the Department of Defense (DoD) and the Department of Health and Human Services (DHHS) currently require two confirmation tests to verify use of heroin, one test for total morphine and a separate test for 6-acetylmorphine (6-AM). Our aim was to determine appropriate free-codeine, free-morphine, and 6-AM cutoff concentrations that could be substituted for total-morphine, total-codeine, and 6-AM cutoff concentrations and to develop a less labor-intensive method for measuring codeine, morphine, and 6-AM. METHODS: Urine samples containing opiates were extracted, derivatized, and analyzed using gas chromatography-mass spectrometry with selective ion monitoring. RESULTS: The limits of detection for codeine, morphine, and 6-AM were 6, 5, and 0.5 microg/L, respectively. Recoveries were >90%. Quantification was linear over the concentration range of 6-1000 microg/L for codeine, 5-5000 microg/L for morphine, and 0.5-800 microg/L for 6-AM. Cutoff concentrations for confirmation of opiates were 100, 100, and 10 microg/L for free codeine, free morphine, and 6-AM. CONCLUSION: The proposed cutoff concentrations for free morphine and 6-AM provide better detection windows for morphine and heroin use than the cutoff concentrations for total morphine and 6-AM used at present. Detection of free codeine, instead of total codeine, simplifies interpretation of codeine use. The single-extraction method enables simultaneous, less labor-intensive analysis of morphine, codeine, and 6-AM.

Codeine↗

PubMed1998

The MCMI-II and race.

In this study, we investigated MCMI-II profile differences in a sample of 65 Black and 164 White psychiatric inpatients. A multivariate analysis of variance (MANOVA) yielded a significant multivariate effect associated with race, with Black patients scoring significantly higher on the Histrionic, Narcissistic, Paranoid, Drug Dependent and Delusional Disorder scales. A second MANOVA was conducted on these 5 scales with a smaller sample of 46 Black and 46 White patients, who were matched for primary Axis I discharge diagnosis and matched for substance abuse comorbidity. This MANOVA did not yield a significant multivariate effect associated with race, and scale differences were attenuated.

Adult↗

PubMed1998

Clients' positive and negative expressiveness within their families and alexithymia.

49 prospective clients from a midwestern urban community, who sought counseling at a university training clinic, completed the Self-expressiveness in the Family Questionnaire and the 20-item Toronto Alexithymia Scale. As predicted, the positive self-expressiveness scores were significantly negatively correlated -.52 with scores on alexithymia, and the negative self-expressiveness scores were significantly positively correlated .34 with alexithymia. These results support the premise that mental health clients' self-reported lack of positive expressiveness and abundance of negative expressiveness within their family context may be attributes associated with their tendency to be alexithymic.

Adult↗

PubMed1998

Effective GC-MS procedure for detecting iso-LSD in urine after base-catalyzed conversion to LSD.

A sensitive method is described to detect isolysergic acid diethylamide (iso-LSD) in urine. The compound was extracted from urine and converted to a C-8 carbanion by sodium ethoxide in ethanol. Protonation of the carbanion by water selectively produced LSD. The conversion of iso-LSD to LSD was almost quantitative (98%). The product was purified by solid-phase fractionation and acid-base separation techniques. The trimethylsilyl derivative of LSD was detected by a gas chromatography-mass spectrometry method. The overall recovery of the procedure was approximately 69%. Quantification of iso-LSD was linear over the concentration range 50-2000 ng/L. In specimen analysis, iso-LSD was detected when the LSD concentration was below the limit of the detection (50 ng/L) of the procedure. Because iso-LSD is a byproduct of illicit preparation of LSD, presence of iso-LSD in urine is an indication of LSD use.

Ethanol↗

PubMed1997

An artificial regulatory circuit for stable expression of DNA-binding proteins in a T7 expression system.

We had earlier overproduced the transcription activator protein C of bacteriophage Mu in a phage-T7 expression system. Although we achieved a high level of overproduction, the expression was not consistent. This could be due to the leaky expression of T7 RNA polymerase in the uninduced state. Introduction of pLysS, a plasmid encoding T7 lysozyme, a natural inhibitor of T7 RNA polymerase, resulted in consistent, but extremely low production of the C protein. To overcome this problem, we have devised an artificial regulatory circuit to obtain stabilised, consistent overproduction of C protein. The C-binding site was cloned downstream from the transcription start point of T7 lys. Upon induction, the C protein produced binds to its site with a very high affinity, possibly acting as a transcriptional roadblock for lys. This would overcome the inhibitory effect of T7 lysozyme on T7 RNA polymerase.

Bacteriophage T7↗

PubMed1997

Use of protein A gene fusions for the analysis of structure-function relationship of the transactivator protein C of bacteriophage Mu.

A sensitive dimerization assay for DNA binding proteins has been developed using gene fusion technology. For this purpose, we have engineered a gene fusion using protein A gene of Staphylococcus aureus and C gene, the late gene transactivator of bacteriophage Mu. The C gene was fused to the 3' end of the gene for protein A to generate an A-C fusion. The overexpressed fusion protein was purified in a single step using immunoglobulin affinity chromatography. Purified fusion protein exhibits DNA binding activity as demonstrated by electrophoretic mobility shift assays. When the fusion protein A-C was mixed with C and analyzed for DNA binding, in addition to C and A-C specific complexes, a single intermediate complex comprising of a heterodimer of C and A-C fusion proteins was observed. Further, the protein A moiety in the fusion protein A-C does not contribute to DNA binding as demonstrated by proteolytic cleavage and circular dichroism (CD) analysis. The assay has also been applied to analyze the DNA binding domain of C protein by generating fusions between protein A and N- and C-terminal deletion mutants of C. The results indicate a role for the region towards the carboxy terminal of the protein in DNA binding. The general applicability of this method is discussed.

Amino Acid Sequence↗

PubMed1996

Gas chromatographic/mass spectrometric detection of narcotine, papaverine, and thebaine in seeds of Papaver somniferum.

In addition to codeine and morphine, three more compounds: narcotine (noscapine), papaverine, and thebaine were found in Indian and Netherlands poppy seeds (Papaver somniferum L). The compounds were detected by a GC/MS technique and the identities were confirmed by comparing retention times and ion ratios with the known references. The concentrations of codeine, morphine, thebaine, papaverine, and narcotine were 44, 167, 41, 67, and 230 micrograms/g in Indian poppy seeds, and were 1.8, 39, 1.0, 0.17, 0.84 micrograms/g in Netherlands poppy seeds, respectively. Because these compounds may be urinary products after poppy seed consumption, the lowest detectable concentrations of codeine, morphine, thebaine, papaverine, and narcotine in urine are of interest and were found to be 4, 4, 5, 0.4, and 4 ng/ml, respectively. The detection of urinary narcotine, papaverine, or thebaine may be utilized to differentiate poppy seed consumption from illicit codeine, morphine, or heroin use.

Gas Chromatography-Mass Spectrometry↗

PubMed1996

One-step esterification of benzoylecgonine with dimethylformamide-dipropylacetal or dimethylformamide-diisopropylacetal in the presence of pyridine.

A simple procedure was developed to derivatize benzoylecgonine extracted from urine for subsequent confirmation by gas chromatography-mass spectrometry. The compound was esterified with dimethylformamide-dipropylacetal (DMF-DPA) or dimethylformamide-diisopropylacetal (DMF-DIPA) to the corresponding propyl and isopropyl esters. The optimum reaction condition was found to be heating the reaction mixture in the presence of pyridine at 100 degrees C for 30 min. The procedure is a one-step esterification followed by evaporation of excess reagents. When benzoylecgonine was extracted from urine using a solid-phase extraction technique and derivatized with this procedure, the compound was detected at a level as low as 10 ng/mL. Quantitation was linear over the concentration range 10-8000 ng/mL.

Acetals↗

PubMed1994

Amphetamine as an artifact of methamphetamine during periodate degradation of interfering ephedrine, pseudoephedrine, and phenylpropanolamine: an improved procedure for accurate quantitation of amphetamines in urine.

During periodate degradation of interfering ephedrine, pseudoephedrine, and phenylpropanolamine in the extraction of methamphetamine from urine, it was observed that a small amount of methamphetamine was demethylated to amphetamine. although all three interfering phenylpropanolamines could be degraded by periodate at pH 5.2 and above, this periodate-mediated transformation of methamphetamine to amphetamine was observed only at pH 9.1 and above. Therefore, to avoid this transformation, a pH of 6.2 was used for the oxidative degradation of phenylpropanolamines. The excess periodate was then reduced with thiosulfate or ascorbic acid prior to the extraction of methamphetamine using a basic pH.

Amphetamine↗

PubMed1993

Effect of freezing on the concentration of drugs of abuse in urine.

Benzoylecgonine, 11-nor-delta 9-tetrahydrocannabinol-9-carboxylic acid (THC-acid), phencyclidine, codeine, morphine, amphetamine, methamphetamine, and lysergic acid diethylamide were dissolved in urine, stored frozen in plastic tubes at -16 to -18 degrees C, defrosted, transferred to other tubes, and analyzed by gas chromatography/mass spectrometry (GC/MS); no significant loss of compound was observed, except for THC-acid, which showed an average loss of 11%, ranging from 0 to 34% of the total concentration. The loss is attributed to the decrease in solubility of the compound and to adherence to the side of the container during freezing.

Freezing↗

PubMed1990

Gas chromatographic-electron-impact mass fragmentometric determination of lysergic acid diethylamide in urine.

A sensitive method for the detection and quantitation of lysergic acid diethylamide (LSD) in urine was developed. After initial solvent extraction, the compound was further purified by liquid-liquid extraction or by solid-phase extraction. The trimethylsilyl derivative of LSD was detected by gas chromatography-mass spectrometry (GC-MS) operated in the electron-impact mode with selected-ion monitoring. The presence of LSD was confirmed by comparing retention times and relative abundances of ions of unknowns with that of a standard. The recovery of this procedure was greater than 89%. The intra-run and inter-run coefficients of variation were less than 5% and less than 7%, respectively. This procedure allows detection of LSD concentrations as low as 29 pg/ml. Quantitation of LSD was linear over the concentration range 50-2000 pg/ml.

Gas Chromatography-Mass Spectrometry↗

PubMed1989

Validity testing of commercial urine cocaine metabolite assays: I. Assay detection times, individual excretion patterns, and kinetics after cocaine administration to humans.

A validity study of eight commercial urine assays for detection of cocaine metabolite was performed on clinical specimens collected from human subjects who received single 20-mg intravenous doses of cocaine hydrochloride. The specimens were collected under controlled conditions and analyzed in random order under blind conditions. Benzoylecgonine concentration in each specimen also was determined by gas chromatography/mass spectrometry (GC/MS). Mean times of detection of the last positive specimen (greater than or equal to 300 ng/mL of benzoylecgonine equivalents) after cocaine administration varied among seven of the commercial tests from 16.9 to 52.9 h in the following ascending order: Toxi-Lab less than TDx = EMIT dau = EMIT st less than Abuscreen less than Coat-A-Count = Double Antibody. In contrast, a commercial spot test (KDI Quik Test) which was evaluated for detection of cocaine metabolite produced both false positives and false negatives for benzoylecgonine and was not considered to be a valid test for detection of cocaine metabolite. Half-lives of excretion of benzoylecgonine among four subjects varied from 5.9 to 7.9 h, and overall recovery of benzoylecgonine varied from 15.0 to 34.3% of the administered dose of cocaine.

Adult↗

PubMed1986

Rotavirus infection among children in hospital in Nigeria.

Faecal samples of 139 Nigerian infants and young children admitted to hospital for gastro-enteritis and of 169 admitted for various other illnesses were tested for rotaviruses by an ELISA technique. Rotaviruses were detected significantly more often in those with gastro-enteritis (20.1%) than in those with other illnesses (3.6%). By contrast, in a representative sample of the population from which the patients had been derived no difference was observed between two similar groups in either isolation or detection rates of recognised enteric bacterial pathogens or intestinal parasites. Hence, as elsewhere, rotaviruses are the most significant enteric pathogens associated with gastro-enteritis among infants and young children in this locality.

Age Factors↗