title: Application of computer taxonomic techniques to the study of cutaneous propionibacteria and skin-surface lipid.
abstract: Colonisation of the forehead by propionibacteria and the composition of both free fatty acid and fatty acid of the triglyceride fraction of skin-surface lipid were studied, and the results were analysed using numerical taxonomic techniques. The density and prevalence of propionibacteria increased with age in a population of 230 children aged 5-18 years. The fatty-acid composition of casual sebum on the forehead changed with age, suggesting that the prevalence and density of organisms may be related to lipid composition. Cluster-analysis techniques revealed groups of individuals who resembled each other with respect to their triglyceride and free-fatty-acid profiles. These groups tended to consist of subjects who were of a similar age and maturity, and who were similarly colonised with propionibacteria. However, no relationship was evident between the composition of lipid and clinical acne.
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D002784:Cholesterol / Q000502:physiology; D003201:Computers; D004075:Diglycerides / Q000032:analysis; D005230:Fatty Acids, Nonesterified / Q000032:analysis; D005260:Female; D006801:Humans; D008055:Lipids / Q000032:analysis*; D008297:Male; D011424:Propionibacterium / Q000302:isolation & purification*; D012867:Skin / Q000032:analysis* / Q000382:microbiology; D014280:Triglycerides / Q000032:analysis
chemical_list: D004075:Diglycerides; D005230:Fatty Acids, Nonesterified; D008055:Lipids; D014280:Triglycerides; D002784:Cholesterol