No abstract

Keloids are proliferative fibrous growths that result from an excessive tissue response to skin trauma. They often occur sporadically, but in some families a genetic predisposition to keloids has been observed. Here we studied two families with an autosomal dominant inheritance pattern of keloids. One African-American family showed a high degree of variability in the extent of keloid formation between family members, whereas the second family from Japan showed a pattern of full penetrance and the formation of only small keloids. We performed a genome-wide linkage search for genes predisposing to keloid formation in these two families. We identified linkage to chromosome 2q23 (maximal two-point LOD score of 3.01) for the Japanese family. The African-American family showed evidence for a keloid susceptibility locus on chromosome 7p11 (maximal two-point LOD score of 3.16). The observed locus heterogeneity in autosomal dominant keloid disease is consistent with the clinical heterogeneity of this scarring disorder. Dense microsatellite analysis in these two loci was performed and candidate genes were identified. This study provides the first genetic evidence for keloid susceptibility loci and serves as a basis for the identification of responsible genes.

To date, this is the largest experience with a tissue-engineered skin product in acute wounds, and this study suggests that tissue therapy may be safe and useful.

No abstract

Sources of bias in the National Institute of Standards and Technology ozone Standard Reference Photometer (SRP) maintained by the Bureau International des Poids et Mesures have been investigated. A relative bias of −0.4% in the ozone mole fraction measurement caused by a temperature gradient in the gas cells of the instrument was characterized and corrected for in a modified version of the instrument. A second relative bias of +0.5% due to the multiple reflections of light within the gas cells was also corrected. The Guide to the Expression of Uncertainty in Measurement approach was used to develop an uncertainty budget for the modified SRP, including a relative value for the ozone absorption cross-section uncertainty of 2.1% (k = 2). The measurement uncertainty for the bias-corrected SRPs is enlarged compared with earlier studies, but their comparability improved.