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Biomedical subjects

R O Hughes

Publications and source records attributed to R O Hughes.

16 recordsLinked to original sources
PubMed1978

Acute pancreatitis and vitamin K deficiency in pregnancy.

Two patients with acute pancreatitis in pregnancy are described. In both, bleeding from vitamin K deficiency occurred after the initial attack of pancreatitis and the bleeding tendency was successfully treated with vitamin K.

Acute Disease↗
PubMed1975

Reduced carbohydrate intake in the preparatory diet and the reliability of the oral glucose tolerance test.

Two USAF flying populatins of 622 subjects each were subjected to the oral glucose tolerance test. One of these populations was prepared for the test by the ingestion of at least 300 grams per day (g/d) of dietary carbohydrate for the 3 d preceding the test; the other by 150 g/d of dietary carbohydrate. Statistical analysis of the data obtained from these populations revealed no change in the reliability of the oral glucose tolerance test as a diagnostic tool. Thaf school of Aerospace Medicine Consultation Service on all patients undergoing oral glucose tolerance tests.

Adult↗
PubMed1969

Exercise-induced asthma.

Tests in three patients with asthma occurring only on exertion showed that F.E.V.(1) fell progressively on exercise, to reach a minimum after 10 minutes. All patients showed a striking metabolic acidosis, with an accumulation of the products of anaerobic metabolism.

Acidosis, Respiratory↗
PubMedDate not supplied

Detection of amphetamine and methamphetamine in urine by gas chromatography/mass spectrometry following derivatization with (-)-menthyl chloroformate.

A gas chromatography/mass spectrometry assay was developed for the detection of amphetamine and methamphetamine in urine. These drugs were detected as carbamate derivatives following reaction with (-)-menthyl chloroformate. Selected ion monitoring of the 226, 182, and 227 dalton ions for amphetamine and the 240, 102, and 196 dalton ions for methamphetamine provided positive analyte identification. Quantitative values obtained by isotope dilution mass spectrometry displayed a linear response from below 50 to above 6,000 ng/mL. Differentiation of over-the-counter (R)-methamphetamine from illicit (S)-methamphetamine was accomplished by chromatographic separation of the diastereomeric derivatives on an achiral column. No interferences were observed from ephedrine, pseudoephedrine, phentermine, phenylpropanolamine, or 2-phenylethylamine.

Amphetamine↗
PubMedDate not supplied

Forensic drug testing for opiates. VI. Urine testing for hydromorphone, hydrocodone, oxymorphone, and oxycodone with commercial opiate immunoassays and gas chromatography-mass spectrometry.

Opiate testing for morphine and codeine is performed routinely in forensic urine drug-testing laboratories in an effort to identify illicit opiate abusers. In addition to heroin, the 6-keto-opioids, including hydromorphone, hydrocodone, oxymorphone, and oxycodone, have high abuse liability and are self-administered by opiate abusers, but only limited information is available on detection of these compounds by current immunoassay and gas chromatographic-mass spectrometric (GC-MS) methods. In this study, single doses of hydromorphone, hydrocodone, oxymorphone, and oxycodone were administered to human subjects, and urine samples were collected before and periodically after dosing. Opiate levels were determined in a quantitative mode with four commercial immunoassays, TDx opiates (TDx), Abuscreen radioimmunoassay (ABUS), Coat-A-Count morphine in urine (CAC), and EMIT d.a.u. opiate assay (EMIT), and by GC-MS. GC-MS assay results indicated that hydromorphone, hydrocodone, oxymorphone, and oxycodone administration resulted in rapid excretion of parent drug and O-demethylated metabolites in urine. Peak concentrations occurred within 8 h after drug administration and declined below 300 ng/mL within 24-48 h. Immunoassay testing indicated that hydromorphone, hydrocodone, and oxycodone, but not oxymorphone, were detectable in urine by TDx and EMIT (300-ng/mL cutoff) for 6-24 h. ABUS detected only hydrocodone, and CAC failed to detect any of the four 6-keto-opioid analgesics. Generally, immunoassays for opiates in urine displayed substantially lower sensitivities for 6-keto-opioids compared with GC-MS. Consequently, urine samples containing low to moderate concentrations of hydromorphone, hydrocodone, oxymorphone, and oxycodone will likely go undetected when tested by conventional immunoassays.

Enzyme Multiplied Immunoassay Technique↗
PubMedDate not supplied

MDA-MDMA concentrations in urine specimens.

Urine specimens collected from active-duty U.S. Army personnel were submitted for analysis to the Tripler Army Medical Center, Forensic Toxicology Drug Testing Laboratory as part of the random drug testing program. During an 18-month drug-screening period, 34 specimens tested positive for amphetamines with the Roche Abuscreen Radioimmunoassay for Methamphetamine (High Specificity); based on gas chromatographic-mass spectrometric (GC-MS) analysis, the presence of 3,4-methylenedioxymethamphetamine (MDMA) was suspected. These samples were subsequently submitted to the Division of Forensic Toxicology, Office of the Armed Forces Medical Examiner, Armed Forces Institute of Pathology for further testing. All 34 samples screened positive using both the Abbott TDx Amphetamine/ Methamphetamine II assay and the Amphetamine class assay. Confirmation and quantitation by GC-MS revealed the presence of both MDMA and 3,4-methylenedioxyamphetamine (MDA) in all samples. The MDMA concentrations ranged from 0.38 to 96.2 mg/L (mean, 13.4 mg/L) and the MDA concentrations ranged from 0.15 to 8.6 mg/L (mean, 1.6 mg/L). The mean ratio of MDA, the N-demethylation metabolite of MDMA, to MDMA was 0.15, similar to the ratio of amphetamine, the N-demethylation metabolite of methamphetamine, to methamphetamine of 0.10. The presence of MDA in urine specimens at a concentration approximately 10-15% that of the MDMA present is consistent with MDMA metabolism, which may be indicative of the use of MDMA only, as compared with the combined use of both drugs.

3,4-Methylenedioxyamphetamine↗