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Biomedical subjects

D J O'Neil

Publications and source records attributed to D J O'Neil.

5 recordsLinked to original sources

Differentiation of side chain isomers of ring-substituted amphetamines using gas chromatography/infrared/mass spectrometry (GC/IR/MS).

Common analytical methods used for identifying samples obtained from clandestine laboratories were evaluated for their ability to differentiate between possible amphetamine isomers and homologs. A series of ring-substituted (4-methyl, 4-methoxy, and 3,4-methylenedioxy) amphetamine and N-methylphenethylamine isomers was analyzed using color tests, thin-layer chromatography, gas chromatography/mass spectrometry (GC/MS) and GC/infrared (GC/IR). The N-acetyl derivatives of the isomers were analyzed using GC/IR/MS. GC/IR/MS readily differentiated the 4-methylphenylalkylamine isomers. MS and IR spectra were also obtained for each pair of the 4-methoxyphenylalkylamine isomers and the 3,4-methylenedioxyphenylalkylamine isomers, but differentiation via GC/IR/MS was difficult. The N-acetyl derivatives of each pair of isomers could be readily differentiated using GC/IR/MS. Good library researchable spectra for N-acetylamphetamine could be obtained for IR identification with 10 ng (on-column) and MS identification with 2 ng. The spectrometrically independent IR and MS data obtained for the N-acetyl derivatives indicated that the combination of GC/IR/MS can add a significant level of confidence in the analysis of ring-substituted arylalkylamines.

Amphetamines

Crohn's disease with pelvic abscess appearing as lumbar disc herniation.

Crohn's disease (regional enteritis) is a chronic inflammatory disease of the bowel with well-documented clinical manifestations and complications. This report of a 35-year-old woman with Crohn's disease outlines the clinical presentation and studies illustrating "quiescent" regional enteritis. The patient was treated for one of the complications of this disease entity. She was referred to the orthopedic clinic with symptoms of lumbar disc syndrome, as well as a painful hip. Crohn's disease was diagnosed and assumed to be well controlled. Physical examination revealed a subgluteal abscess, ostensibly caused by Crohn's disease. The abscess fistulized through the greater sciatic notch. The capricious nature of this disease entity is self-evident.

Abscess

Contamination of illicit phencyclidine with 1-piperidinocyclohexanecarbonitrile.

A retrospective study of illicit phencyclidine (PCP), which consisted of 94 different cases or 213 individual samples, has shown that one third of both the powder/tablets and green plant material contained the synthetic contaminant 1-piperidinocyclohexanecarbonitrile (PCC). The mole % PCC/PCP ranged from 1 to 68%. The method of analysis was gas chromatography (3% OV-7, 205 degrees C) and in preparation for analysis the sample was dissolved directly in chloroform or extracted from a strongly acidic solution (0.1 N HCl). Using these extraction conditions PCC was found not to undergo measurable decomposition.

Chromatography, Gas