Analysis of lung air from patients with bronchogenic carcinoma and controls using gas chromatography-mass spectrometry.

Volatile metabolites present in expired lung air were collected by odor sampling techniques and analyzed by gas chromatography-mass spectrometry. The study population included controls matched for age and smoking history with patients newly diagnosed with lung carcinoma. Significantly greater concentrations of o-toluidine were found in the lung air of patients with lung carcinoma than either age-matched or younger controls.

Characterization of wax esters, triglycerides, and free fatty acids of follicular casts.

The abnormal impactation of a sebaceous follicle (the follicular cast) has been implicated as the preclinical lesion of acne vulgaris. We have characterized the lipid composition of these structures in the first of a series of studies aimed at the identification of sebaceous lipids that may be associated and/or responsible for the initiation of clinical lesions. The lipid composition of follicular casts was analyzed using thin-layer chromatography, gas chromatography, and mass spectrometry.

Characterization of pathogenic bacteria by automated headspace concentration-gas chromatography.

Automated headspace concentration-gas chromatography (AHC-GC) was used to profile the volatile metabolites produced by Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa and Staphylococcus aureus. Bacterial cultures were incubated in trypticase soy broth and examined at 24 h. The profiles were consistent for each genus examined and variation observed among the different strains of each species was chiefly quantitative.

Pathogenic JK group corynebacteria and their similarity to human cutaneous lipophilic diphtheroids.

Aerobic diphtheroids from human skin (commonly referred to as lipophilic diphtheroids), pathogenic bacteria of the JK group, and classic species of the genus Corynebacterium were studied for their cellular fatty acids and mycolates, composition of their cell wall peptidoglycans, nutritional requirements, biochemical reactions, and antibiotic sensitivities. Lipophilic diphtheroids and JK strains were catalase positive and contained corynemycolic acid and meso-diaminopimelic acid in their cell walls, a characteristic shared with all corynebacteria. The lipophilic diphtheroid and JK strains were found to have a strict nutritional requirement for lipid and a similar composition of cellular fatty acid, mycolic acid, and peptidoglycan; they differed only in the multiple antibiotic resistance of the JK strains.