An enzyme combination assay for serum sphingomyelin: Improved specificity through avoiding the interference with lysophosphatidylcholine.

Serum sphingomyelin (SM) has predictive value in the development of atherosclerosis. Furthermore, SM plays important roles in cell membrane structure, signal transduction pathways, and lipid raft formation. A convenient enzymatic method for SM is available for routine laboratory practice, but the enzyme specificity is not sufficient because of nonspecific reactions with lysophosphatidylcholine (LPC).

An autopsy case of fatal repellent air freshener poisoning.

We describe a first fatal case of repellent air freshener ingestion. A 79-year-old Japanese man with Alzheimer-type senile dementia orally ingested repellent air freshener containing three surfactants: polyoxyethylene 9-lauryl ether, polyoxyethylene (40) hydrogenated castor oil, and lauric acid amidopropyl amine oxide (weight ratio of 1.3%).

Differences in reaction specificity toward lipoprotein X and abnormal LDL among 6 homogeneous assays for LDL-cholesterol.

Background: We investigated the reaction specificity toward cholesterol in lipoprotein X (Lp-X) and abnormal LDL among 6 homogeneous assays for low-density lipoprotein cholesterol (LDL-C) based on different measurement principles.

Methods: The homogeneous LDL-C assays used were based on the liquid selective detergent, selective solubilization, elimination, enzyme-selective protection, calixarene complex, and phosphate complex inhibition methods. The fraction with a density of 1.

[Development of the HDL-C and LDL-C direct methods and the subsequent evolution].

Today, more than a decade after the development of direct methods for determining HDL-cholesterol (HDL-C) and LDL-cholesterol (LDL-C) concentrations, there are calls to review the reagents in response to discrepancies in patient samples with increased levels of atypical lipoproteins, such as apoE-rich HDL, IDL, Lp-X, and Lp-Y. Seven direct HDL-C assays showed different reactions toward apoE-rich HDL in sera from patients with CETP deficiency and cholestasis. On the other hand, the reactivity of the direct LDL-C assays to serum samples with elevated levels of IDL, Lp-X, and Lp-Y varied considerably between assay kits from each manufacturer.

Simultaneous identification of the enantiomers and diastereomers of N,O-di-trifluoroacetylated ephedrine and norephedrine in blood plasma using chiral capillary gas chromatography-mass spectrometry with selected ion monitoring.

A method for identifying the enantiomers of N,O-di-trifluoroacetylated ephedrine (EP) and norephedrine (NE) and the enantiomers of pseudoephedrine (PEP) and pseudonorephedrine (PNE) in plasma was developed using chiral capillary gas chromatography-mass spectrometry (GC-MS) with selected ion monitoring (SIM). N,O-Di-trifluoroacethyl (TFA) derivatization was accomplished in a dried hydrochloride extract of plasma (minimum quantity of 0.2 mL).

Stereoisomeric identification of norephedrine derived from methamphetamine or amphetamine: urinalysis results of 33 methamphetamine abusers and 1 amphetamine abuser in Japan.

Stereoisomeric identification of norephedrine (NE) derived from methamphetamine (MA) or amphetamine (AM) was investigated by SIM-GC/MS assay using the urine of 33 MA abusers and 1 AM abuser. The assay simultaneously identified TFA-derivatized MA and AM metabolites, including AM, p-hydroxyl-MA (p-HMA), and p-hydroxyl-AM (p-HAM). The analysis lasted approximately 43 min, with a signal-to-noise ratio of >or=3 and a detection limit of 50 ng/mL.

Accidental strangulation of a mentally retarded patient by a clothing collar: a case report.

A 40-year-old mentally retarded woman died of accidental strangulation in a nursing home. She was found in a kneeling position with her hands on her knees and the collar of her clothing compressing the front and sides of the neck. Before the accident, a nurse had dressed the patient in one-piece overall-style pyjamas put on back to front so that she could not remove the garment herself.

Enantiomer analysis of a new street drug, 3,4-methylenedioxy-N-methyl-butanamine, in rat urine.

A new street drug, 3,4-methylenedioxy-N-methyl-butanamine (MBDB), has been found in Japan recently. The stereoisomer monitoring and the urinary excretion kinetics are not determined in biological fluids even though abused MBDB is a racemic form [enantiomer ratio (-/+) = 1.00].