An appraisal of intermediate filament expression in adult and developing pancreas: vimentin is expressed in alpha cells of rat and mouse embryos.

Intermediate filaments are frequently used in studies of developmental biology as markers of cell differentiation. To assess whether they can be useful to identify differentiating pancreatic endocrine cells, we examined the pattern of expression of nestin, cytokeratin 20, and vimentin on acetone-fixed cryosections of rat adult and developing pancreas. We also studied vimentin expression in mouse embryonic pancreas at E19. Cytokeratin 20 was found in all pancreatic epithelial cell lineages during the entire development of the rat gland and in the adult animals. Under our experimental conditions, therefore, cytokeratin 20 is not an exclusive marker of rat duct cells. Nestin was detected exclusively in stromal cells either in the adult or developing rat pancreas. Vimentin was observed within cells located in the primitive ducts of rat pancreas starting from E12.5. Their number rapidly increased, reaching its highest level in newborn animals. Vimentin was also spotted in alpha cells starting from E12.5 but disappeared soon after birth, likely identifying immature or recently differentiated alpha cells. In addition, vimentin was observed in duct and alpha cells of mouse developing pancreas showing that its expression in such cells is not an event restricted to the rat. This manuscript contains online supplemental material at http://www.jhc.org. Please visit this article online to view these materials.

Treatment of acute bacterial conjunctivitis with topical netilmicin.

PURPOSE: This study compares the clinical and microbiologic value of topical netilmicin with that of gentamicin in the treatment of acute bacterial conjunctivitis. METHODS: A double-blind, randomized, prospective, controlled study was performed in 209 patients. One to two drop(s) of either antibiotic was applied to the affected eye(s) four times a day for up to 10 days. Patients were examined at the time of diagnosis and after 3, 5, and 10 days. Clinical efficacy was measured as the cumulative sum score (CSS) of the key signs and symptoms of acute bacterial ocular infection. Sensitivity/resistance was evaluated using the disk diffusion method. RESULTS: Drug efficacy assessment was restricted only to patients with positive baseline culture results (n = 121). Of the isolated organisms, 96.9% were sensitive to netilmicin, whereas only 75.0% were sensitive to gentamicin (p = 0.00001). Netilmicin provided a broad-spectrum coverage comparable with that of ciprofloxacin, ofloxacin, and norfloxacin. Netilmicin also was more effective than gentamicin in eradicating infections (p = 0.001 at day 5 and p = 0.037 at day 10) and in ameliorating the CSS (p = 0.037 at day 3, p = 0.001 at both day 5 and day 10). Only minor adverse events occurred in patients treated with either netilmicin or gentamicin. CONCLUSIONS: This study demonstrates that netilmicin is a safe and effective antibiotic that can be used as first-line therapy for the treatment of acute bacterial conjunctivitis.