Expression profile of fas-fas ligand in spiral ganglion cells during apoptosis.

OBJECTIVES: To examine the expression profile of Fas-Fas ligand (FasL) during glutamate (Glu)-induced spiral ganglion cell (SGC) apoptosis. METHODS: Cultured SGCs were treated with 10-mM, 25-mM, and 50-mM concentrations of Glu and incubated for 24 or 48 hours. The expression intensity of FasL, Fas, caspase 3, and morphology of single SGC were evaluated using immunofluorescence staining. RESULTS: In semiquantitative analysis of the Glu-treated SGC, FasL, and caspase 3 expression intensity were increased with concentration- and time-dependent manner. Fas expression intensity did not change with different concentration at 48 hours. In morphologic analysis of the Glu-treated SGC, number of apoptotic cells were increased with concentration- and time-dependent manner. CONCLUSION: FasL was expressed in apoptotic SGCs, suggesting that the Fas-FasL signaling pathway may be involved in the Glu-induced apoptosis of dissociated SGCs.

Epitympanoplasty with mastoid obliteration technique: a long-term study of results.

OBJECTIVE: To report the long-term results of epitympanoplasty with mastoid obliteration technique. SUBJECTS AND METHODS: Two hundred adult cases had undergone epitympanoplasty with mastoid obliteration from December 1994 to May 2003. The mean postoperative observation period was 91 months, with a minimum of five years. Epitympanoplasty with mastoid obliteration technique has four major procedures: the widening of the external auditory canal and removal of the scutum; preservation of the posterior canal wall; epitympanoplasty; and mastoid obliteration. We examined postoperative complications and hearing outcomes. RESULTS: There was no retraction pocket formation and recurrence of cholesteatoma. Residual cholesteatoma in the tympanic cavity was seen in 10 cases (5%) and three cases were seen in the mastoid cavity (1.5%). Other complications were otorrhea (15 cases), perforation (8 cases), material extrusion (6 cases), and posterior auricular infection (4 cases). The average preoperative pure tone air-bone gap, postoperative pure tone air-bone gap, and air-bone gap closure were 31.5 +/- 12.4 dB, 25.3 +/- 12.2 dB, and 6.2 +/- 12.6 dB, respectively. There were significant differences between the preoperative and postoperative values (P < 0.01). CONCLUSIONS: The authors believe that epitympanoplasty with mastoid obliteration technique can combine the advantages of canal wall down and canal wall up techniques while improving their shortcomings.