The identification of a third fragile site, FRAXF, in Xq27--q28 distal to both FRAXA and FRAXE

PURPOSE: Use of fluoroquinolone agents as single drug treatment for severe bacterial keratitis requires that adequate stromal drug concentrations are achievable that exceed the MIC90 for common corneal pathogens. The purpose of this study, therefore, is to document the human stromal penetration of the fluoroquinolone, ciprofloxacin, in human tissue obtained from patients undergoing penetrating keratoplasty. METHODS: Twelve patients, all with intact corneal epithelia, received 0.3% ciprofloxacin (Ciloxan) eyedrops every 15 minutes for the first hour and then every hour for 10 hours before their scheduled keratoplasty. Corneal tissue samples obtained from the excised buttons at the time of surgery were frozen and subsequently analyzed for drug concentration using high-pressure liquid chromatography. RESULTS: A mean corneal tissue concentration of 5.28 +/- 3.4 micrograms/g tissue (mean +/- standard deviation) of ciprofloxacin was determined. Tissue levels ranged from 1.43 micrograms/g of tissue to 10.58 micrograms/g of tissue. CONCLUSION: Ciprofloxacin penetration was variable in patients with an intact epithelium and, in some cases, did not exceed the MIC90 for some gram-positive organisms. The presence of an epithelial defect is expected to potentiate the penetration of ciprofloxacin to most likely exceed the MIC90 for most corneal pathogens.     

Antioxidant from maize and maize fermented by Marasmiellus sp. as stabiliser of lipid-rich foods

Mycelia of Marasmiellus sp. (KUM 50061) were grown on maize for antioxidant production. This formed the mycelial biomass which was then extracted with methanol. Antioxidant activity of methanolic extract was analysed by the TBARS assay, using egg yolk or palm cooking oil as a source of lipid, rather than the conventional rat liver microsomes or linoleic acid. Results showed that at low concentrations of extracts, inhibition of lipid peroxidation in buffered egg yolk was marginal, but significant inhibitory response was evident as the concentrations was increased. The concentration of extract of fermented maize that caused 50% inhibition of lipid peroxidation of buffered egg yolk was 6 mg/ml. Results also indicated a decrease in peroxidation in heated cooking oil supplemented with dried extract compared to unsupplemented cooking oil. The concentration range of dried extract supplementation was 0.2–5 mg/ml. Increasing the extract concentration did not significantly alter the inhibition of peroxidation. The inhibition effect was still evident even at the lowest concentration tested, and was found to be better than catechin and BHA. This pattern of observation was consistent over the 12-day period of observation. Therefore, the possibility of substituting synthetic antioxidants such as BHA and BHT, which are known to be carcinogenic, with antioxidants of natural origin is suggested.