Fuyuki Enomoto

EFFECT OF ERYTHROMYCIN ON OTITIS MEDIA WITH EFFUSION IN EXPERIMENTAL RAT MODEL

To understand the mechanism of erythromycin (EM) on otitis media with effusion, we examined its effects on leukocyte accumulation and expression of adhesion molecules L-selectin and Mac-1, using a rat experimental model Administration of EM inhibited leukocyte (neutrophil) accumulation in the middle ear cavity after LPS stimulation. Moreover, EM downregulated L-selectin expression and inhibited interleukin (IL)-8-induced upregulation of Mac-1 on peripheral blood neutrophils. These finding suggests that EM may improve otitis media with effusion by inhibiting neutrophil accumulation in the middle ear cavity through modulating the expression of adhesion molecules L-selectin and Mac-1 on peripheral blood neutrophils.

Effect of new macrolides on the expression of adhesion molecules on neutrophils in chronic sinusitis.

To elucidate the mechanisms involved in the action of new macrolides on chronic sinusitis, we examined the effects of clarithromycin (CAM) and roxiythromycin (RXM) on the expression of adhesion molecules (L-selectin and Mac-1) on peripheral blood neutrophils of individuals with chronic sinusitis. The administration of CAM and RXM slightly inhibited the down-regulation of L-selectin expression on neutrophils induced by interleukin (IL)-8 stimulation. Furthermore, the administration of CAM strongly inhibited the IL-8-induced up-regulation of Mac-1 expression on neutrophils. These observations suggest that the new macrolides such as CAM and RXM may affect the functions of neutrophils in chronic sinusitis by modulating the expression of L-selectin and Mac-1 molecules on neutrophils, thereby attenuating the adhesion of neutrophils.

Modulation of neutrophil adhesion to vascular endothelial cells in rat experimental otitis media treated with a macrolide

OBJECT We previously reported that erythromycin (EM) affected the adhesion molecules that interact with neutrophils and inhibited neutrophil infiltration in a rat experimental otitis media model. PURPOSE The purpose of the present study was to examine whether EM affects the adhesion of rat neutrophils to endothelial cells. METHODS The adhesion of neutrophils to WK-5 endothelial cells was evaluated. One group of rats was given EM for 2 weeks, while the other group received no treatment. The adhesion of peripheral-blood neutrophils and neutrophils accumulated in the middle ear from these two groups were compared. RESULTS Two-week EM pretreatment inhibited adhesion of neutrophils to WK-5 cells. The adhesion of neutrophils accumulated in the middle ear cavity to WK-5 cells was significantly higher than that of peripheral-blood neutrophils from control rats. CONCLUSION The results suggest that EM affects the adhesion of neutrophils to endothelial cells.

Distribution and role of mast cells in human tonsil

Abstract Mast cells (MC) are an important component in inflammation and immune surveillance mechanisms, and play a key role in defense against bacterial infection. Since tonsils are involved in inflammatory and allergic reactions, and because mast cells are also part of these reactions, this study was to clarify the local distribution of human mast cells in tonsils. Tonsillar tissues were from patients suffering from chronic tonsillitis or hyperplastic tonsils, divided into atopy and non-atopy groups. The localization and distribution of mast cells was determined by immunohistological study using anti-tryptase and anti-C-kit antibodies. Furthermore, the expression of IgE was also investigated. We revealed that in both groups, mast cells were distributed in perivascular and interfollicular areas. However, the expression of tryptase and C-kit in interfollicular areas was more significant in non-atopy group rather than atopy group. In addition, IgE was significantly expressed in perivascular areas, crypt and subepithelial tissue of tonsils from atopy group. In contrast, there was no remarkable increase of IgE expression in interfollicular areas. The finding that mast cells are differently distributed in the tonsillar tissues incited us to investigate the possible new role of mast cells in the tonsillar tissues in inflammatory or allergic conditions.

Effects of Erythromycin on Neutrophil Chemotaxis in Rats

Background: Erythromycin showed an inhibitory effect on neutrophil exudation to the middle ear cavity in a rat model of otitis media. Methods: Erythromycin (EM) was administered intraperitoneally into male Splague-Dawley rats at 10 mg/kg once daily for 7 or 14 days. A purified neutrophil suspension was employed in the neutrophil chemotaxis experiment using the Boyden chamber method. Results: A significant increase in migration was observed at 50 and 100 ng/ml growth-related gene product (GRO) as compared to the assay with the addition of serum alone. Strong migration activity was also seen in the presence of zymosanactivated C5a in the assay medium. Treatment with EM for both 7 and 14 days suppressed the enhanced migration of neutrophils induced by 50 and 100 ng/ml GRO. In contrast, C5a significantly enhanced neutrophil migration under the treatment of EM for both 7 and 14 days. Conclusion: The present study first revealed that EM administration to animals selectively inhibited the GRO-induced migration of neutrophils, which may contribute to its antiinflammatory effect on the upper respiratory mucosa.

Study of Expression of L-Selectin and Mac-1 in Pre- and Post-Operative Patients with Obstructive Sleep Apnea Syndrome

In obstructive sleep apnea syndrome (OSAS), it has recently been reported that complications such as hypertension, ischemic heart disease, and cerebral disease occur at high rates. In this study we assessed the function of neutrophils in patients with OSAS. By taking blood samples before and after operative treatment, we measured the levels of neutrophil-adhesive molecules, L-selectin and Mac-1.

Benign Lymphoepithelioma of Parotid Gland; A Case Report.

Benign lymphoepithelioma is a comparatively rare disease which shows sialaden tissue findings which are pathohistologically similar to those seen in Sjogrens syndrome. We recently treated 27-year-old female with a benign lymphoepithelioma in the parotid gland. She had no signs or symptoms other than a tumor in the right parotid gland. There was no xerostomia. A definite diagnosis was reached from the pathohistological appearance of resected tissue. Since benign lymphoepithelial lesions may become malignant lymphomas, this patient must be followed carefully.