This study provides surgeons with a better understanding of the anatomy of the anterior ethmoidal canal.

We speculate that the posteroinferior end of the superior turbinate is the best landmark for identifying the natural ostium of the sphenoid sinus. Furthermore, the natural ostium should ideally be searched from a superior and medial aspect in relation to the posteroinferior end of the superior turbinate.

Recently, it was found that IL-13 is involved in allergic inflammation and mucus hypersecretion in in vivo animal models. However, the role of IL-13 in in vitro cellular models has yet to be determined. This study aimed to investigate the direct effect of IL-13 on mucin gene expression and mucin secretion in cultured normal human nasal epithelial cells. After treatment with IL-13, total mucin and MUC5AC mucin levels were measured using an immunoblotting assay. MUC2, MUC5AC and MUC8 mRNA expression were determined using reverse transcription-polymerase chain reaction. Also, immunostaining was performed using a MUC5AC antibody on histologic and cytospin slides. After treatment with > or = 5 ng/ml IL-13, the level of total mucin and MUC5AC mucin secretion decreased substantially. The expression of MUC2 and MUC8 mRNA increased with higher concentrations of IL-13, but the expression of MUC5AC mRNA decreased. On the 7th day after IL-13 treatment, a significant decrease in the number of MUC5AC-positive cells was confirmed by immunostaining. These findings indicate that IL-13 suppresses MUC5AC mucin gene expression and mucin secretion in cultured normal human nasal epithelial cells in vitro.

No abstract