Purification and properties of fatty acid synthetase from a human breast cell line

A human mammary epithelial cell line (SKBr3) has been identified in which fatty acid synthetase constitutes up to 28%, by weight of the cytosolic proteins. The enzymes has been purified to near homogeneity from this cell line and some of its properties studied. In common with fatty acid synthetases from other animal tissues, the enzyme is a 480 000 dalton dimer of similar molecular weight subunits, it synthesizes predominantly palmitic acid and is inactive in the absence of free coenzyme A. The kinetic properties and amino acid composition of the enzyme are also similar to those of fatty acid synthetases from various tissues of other animals. Appreciable structural resemblance between human and rodent fatty acid synthetases is indicated by studies on the immunological cross-reactivities of these enzymes.     

Caveat emptor

Inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase are very common and effective treatments for hyperlipidemia. Epidermal cholesterol synthesis has been shown to be essential for maintaining the cutaneous barrier function. We present two patients who experienced cheilitis after beginning treatment of hyperlipidemia with simvastatin (Zocor). The rash resolved after discontinuation of medication and subsequent treatment with topical moisturizers and topical corticosteroids. We suspect that skin barrier dysfunction may occur in the mucosa from inhibitors of HMG-CoA reductase in a manner analogous to the epidermis.     

Patterns of Cryptosporidium oocyst shedding in calves and a comparison of two diagnostic methods

Cryptosporidium spp. oocyst shedding was observed in calves from approximately 1 to 30 days of age. Oocysts were detected by either the Kinyoun acid-fast staining technique (microscopic examination--ME) or a commercially produced enzyme immunoassay EIA). Test concordance between the two detection methods was determined. The mean (+/- SD) number of days to detection of cryptosporidial oocysts was 9.52 +/- 1.92 for the ME and 9.83 +/- 3.19 for the EIA. No significant difference between the means was found (P = 0.17). The period prevalence of cryptosporidiosis was 100% in calves from 1 to 30 days of age. The overall agreement between the ME and EIA was 72%, with a kappa value of 0.42 (SE +/- 0.05). McNemar's test indicated that the proportion of tests determined positive by the two methods was not equal (P < 0.01). The findings or this study indicate moderate agreement between the two diagnostic methods, with the EIA being the more sensitive of the two. However, in most cases the herd-level determination of cryptosporidiosis requires minimal sample sizes and is more economically and easily accomplished by the ME method of detection.