Joseph J. Saady

Postinjury scopolamine administration in experimental traumatic brain injury

A single bolus dose of scopolamine (1.0 mg/kg) or saline (equal volume) was injected (i.p.) at 15, 30 or 60 min after fluid percussion traumatic brain injury in the rat. Scopolamine administered at 15 min postinjury significantly reduced beam walking deficits and body weight loss assessed for 5 days after injury. Scopolamine treatment at 30 or 60 min postinjury had no effect on behavioral outcome assessed for 5 days after injury. Plasma concentrations of scopolamine were measured with a radioreceptor assay. The plasma half-life for scopolamine was 21.6 min in injured rats and 17.3 min in normal rats (P less than 0.05). These results, along with evidence from previous studies, suggest that a brief period of excessive neuronal excitation can produce relatively long-lasting behavioral deficits. The temporal effectiveness of receptor antagonist intervention in this process appears to be brief.

Production of Urinary Ethanol After Sample Collection

As the interest in urine drug testing grows, ethanol is frequently included in drug-abuse screening. Collection of urine for drug testing is less invasive than blood collection and is used to screen employees in a large cross-section of occupations. Because alcohol can be produced from carbohydrates via fermentation, our interest was to determine: (1) if ethanol could be produced in glucose-positive urine (2) under what microbiological conditions would this process occur, and (3) would the urine ethanol concentration be significant. Fourteen urine specimens were selected from the Urinalysis Laboratory of a large medical center. All specimens were tested for ethanol concentration on the day of voiding and were found to be negative (< 0.01 mg/100 mL). Urine glucose concentrations ranged from 0 to > or = 2000 mg/dL. Microbiological examinations were performed on all specimens. Storing the samples at room temperature, five of the specimens produced ethanol over the time course of the study (1 to 21 days) in concentrations ranging from 0.036 to 2.327 g/100 mL. Yeast was identified in the five glucose positive urine samples producing ethanol. Six glucose positive urine samples that did not produce ethanol were found to be yeast negative. Findings indicate that significant ethanol concentrations can develop from glucose and yeast positive urine, after the day of voiding.

Urinary excretion of benzoylecgonine following ingestion of health inca tea

Four males ingested one cup of Health Inca Tea which contained 1.87 mg of cocaine. Urine specimens collected for 36 h post-ingestion were analyzed for benzoylecgonine (BE) by EMIT-d.a.u., TDx and gas chromatography/mass spectrometry (GC/MS). Positive immunoassay results were obtained for 21-26 h post tea ingestion. Discrepant immunoassay results occurred with only one specimen: EMIT positive; TDx negative, 0.25 mg/l; GC/MS, 0.273 mg/l. Quantitative TDx results were well correlated with GC/MS results, r2 = 0.963, n = 45. Maximum urinary BE concentrations ranged from 1.4-2.8 mg/l, occurring from 4-11 h, post ingestion. Total BE excretion in 36 h ranged from 1.05 to 1.45 mg, 59-90% of the ingested cocaine dose. Urinary excretion rate constant (Km) ranged from -0.073 to 0.111/h. Health Inca Tea ingestion should be considered when interpreting urinary BE concentrations.

EMIT-d.a.u. monoclonal amphetamine/methamphetamine assay. II. Detection of methylenedioxyamphetamine (MDA) and methylenedioxymethamphetamine (MDMA)

The cross-reactivity, stereoselectivity and clinical performance of the EMIT-d.a.u. monoclonal amphetamine/methamphetamine immunoassay (EM) for the detection of methylenedioxyamphetamine (MDA) and methylenedioxymethamphetamine (MDMA) in urine was evaluated. The cut-off concentrations of racemic MDA and MDMA were found to be approximately 800 ng/ml and 3000 ng/ml, respectively. The EM assay demonstrated a high selectivity for the S(+) isomer of both MDA and MDMA. Urines collected over a 24-h period from rats administered 20 mg i.v. racemic MDMA were all positive when analyzed by the EM assay. The EM was found vastly superior to the EMIT d.a.u. polyclonal amphetamine/methamphetamine assay for the detection of MDA and MDMA. The EM assay displayed sufficient sensitivity for detection of these drugs following clinical intoxication.

Demonstration of physical dependence following chronic continuous methadone delivery via osmotic minipumps in pregnant rats

The effects of a 14-day (gestation days 7-20) chronic methadone (6.3-9.0 mg/kg/day) infusion via osmotic minipumps were studied on the induction of physical dependence in both pregnant and nonpregnant female rats. Following continued methadone exposure, an acute injection of naloxone (2.0 mg/kg, SC) produced the following symptoms of withdrawal in both pregnant and nonpregnant methadone-exposed rats: increased frequency of head shakes, teeth-chattering and face-rubbing episodes, as well as the induction of burrowing, diarrhea, facial tremor, squeaking and vaginal sniffing. Increased fetal movement in the maternal abdomen was also observed in the pregnant rats. In the saline-exposed pregnant controls, naloxone failed to induce a significant effect. In addition, brain and plasma methadone levels during the various stages of pregnancy (gestation days 8-20) were determined. The methadone levels in plasma were initially variable (gestation days 8-12) but became more constant (approximately 50 ng/ml) from gestation day 14 to 20. Methadone brain levels also followed a similar pattern, except that the brain methadone content was at least 20-fold greater than plasma concentrations at any given time. Thus, relative to the high brain levels, the present data suggest that acute changes in methadone plasma concentration may not be a good index of pharmacological effect.

A hydromorphone and ethanol fatality

A case report is presented of a fatality where death is attributed to the combined central nervous system-depressing effects of ethanol and hydromorphone. Blood and tissue levels of hydromorphone are reported and the concentrations are compared to previously reported data.

EMIT-d.a.u. monoclonal amphetamine/methamphetamine assay. I. Stereoselectivity and clinical evaluation.

The stereoselectivity, cross-reactivity and clinical performance of the EMIT-d.a.u. monoclonal amphetamine(A)/methamphetamine (MA) immunoassay (EM) were evaluated. The cut-off calibrator of the assay was 1000 ng/ml S(+)MA. Analysis of drug-added urines and 72 clinical specimens demonstrated a cut-off for S(+)-amphetamine of approximately 400 ng/ml. The stereoisomeric selectivity of the assay was determined in a concentration vs. response manner by adding pure S(+) or R(-)isomers of A and MA, to drug free urine. The EM assay demonstrated a high selectivity for S(+)-isomers with only one of 16 urine specimens collected following excessive use of nasal inhalers yielding a positive result. This specimen contained 6000 ng/ml R(-)MA. Five-hundred clinical urine specimens were simultaneously analyzed for A or MA by the EM and EMIT-d.a.u. polyclonal (EP) amphetamine assay with 131 positive results confirmed by GC/MS. In five specimens negative by EM while positive by EP, MA was present at concentrations below the 1000 ng/ml cut-off. Two ME false positive results were apparently caused by chlorpromazine (CPZ) metabolites. A study of other phenothiazines or their metabolites gave no false positive results. The possible cross reactivity of the EM assay was further studied for phenyl-isopropylamine analogs or drugs previously reported to react with the EP assay. The EM assay showed much less cross-reactivity than EP to all drugs tested.

A comparison of plasma and serum levels of two tricyclic antidepressants: imipramine and desipramine.

This study was performed to determine the difference, if any, between serum and plasma levels of the tricyclic antidepressant drugs imipramine and desipramine. Serum and plasma samples were drawn simultaneously from patients taking either of these drugs. Statistical analysis indicated no difference in the drug levels; that is, serum and plasma levels were identical.

Cocaine-induced rausch: overt behaviour and plasma concentrations in rhesus monkeys

SummaryThis study was designed to characterize the cocaine-induced rausch or hyperarousal syndrome in rhesus monkeys. This syndrome mimics the stage observed in human abusers bingeing on cocaine and its considered crucial in the progression from recreational use to compulsive abuse. However, little research has focused on this important aspect of cocaine use. Cocaine was administered i.v. at doses of 0.0, 0.5, 1.0 and 2.0 mg/kg. Plasma concentrations were determined by gas chromatograph mass spectrometry (GC/MS) using deuterated internal standards d3 cocaine and d3 benzoylecgonine (BE). Mean plasma concentrations of cocaine, were on samples collected 1 min after infusion, 46 ± 31, 88 ± 15 and 275 ± 116 mg/μl in the 0.5, 1.0 and 2.0 mg/kg dose groups, respectively. There were no detectable concentrations of BE in any of the specimens nor was cocaine detected in the saline controls. Analysis of the behavioural data revealed that the 0.5 and 1.0 mg/kg results were intermediate between the results obtained at doses of 0.0 and 2.0 mg/kg and that the 1.0 mg/kg dose produced a higher response than the 0.5 mg/kg dose up to the 12 min. Regarding individual behavioural signs, those designated escape attempts, checking, feinting, restlessness, searching, vocalizing, chewing, crouching and wide-eyed were noted most frequently. The results showed dose-response relationships for both plasma concentrations of cocaine and for the total number of overt behavioural signs. The plasma concentrations were in the range reported for human cocaine abusers.

EVALUATION OF THE ACCULEVEL THEOPHYLLINE ASSAY

Abstract As a quality assurance study, we evaluated the rapid on-site AccuLevel theophylline assay and compared the results to the reference method of High Performance Liquid Chromatography (HPLC). The rapid result was needed in order to provide more timely treatment for patients presented to the Emergency Medical Department (EMD) who required a quantitative serum theophylline determination early in the course of treatment. A good correlation between the theophylline concentrations simultaneously determined by AccuLevel and HPLC was observed; r2 =0.916, n=96. A slight positive bias by AccuLevel was noted with the mean of concentrations being 11.7 mg/L and 13.2 mg/L for HPLC and AccuLevel, respectively. Precision of the assay was found to be 4.6%. Because of the delay in transporting specimens from the EMD to the Clinical Laboratories at our Medical Center, the EMD was able to obtain quantitative theophylline serum values from 30 minutes to 1.5 hours sooner by using the AccuLevel, on-site test.