[Radiographic study on the efficacy of mandibular advancement in patients with obstructive sleep apnea syndrome].

PURPOSE: To investigate the efficacy and mechanism of mandibular advancement device (MAD) treatment on obstructive sleep apnea syndrome (OSAS) patients. METHODS: Eighty OSAS patients treated with a mandibular protraction appliance were included in the study. Three-dimensional reconstruction technique was used as to measure the changes of upper airway structure and volume before and after MAD treatment. The data was analyzed using SPSS 17.0 software package. RESULTS: The anatomic structure and the reinforcement of soft tissue's collapse in the upper airway changed after application of MAD in OSAS patients; velopharyngeal and laryngopharynx configuration was significantly increased (P<0.01), while oropharyngeal configuration was significantly decreased (P<0.05). CONCLUSIONS: This study demonstrated that pathogeny of OSAS based on morphological characteristics may be removed by mandibular advancement device, the mechanism of efficacy of MAD treatment can be the reduction of airway internal fluctuation and vortex of air.

[The effect of GDNF on matrix-degrading and cell-adhesion during perineural invasion of salivary adenoid cystic carcinoma].

PURPOSE: To investigate the possible contribution of GDNF in matrix-degrading, cell-adhesion during perineural invasion (PNI) of salivary adenoid cystic carcinoma (ACC). METHODS: Totally 42 ACCs and 5 normal salivary tissues were included in the present study．Immunohistochemical staining SP method was used to detect the expression of GDNF,MMP-9,NF-κB,integrin ß1 in ACC specimens and normal salivary tissues. Statistical analysis was performed using SPSS16.0 software package. RESULTS：GDNF was strongly expressed in ACC tumor cells and nerve fibers adjacent to ACC tumor cells. NF-κB, MMP-9, integrin ß1 were positively expressed in ACC cell cytoplasm, integrin ß1 was also found in ACC cell membrane, and NF-κB in nuclei occasionally. The positive expression rate was 69.05%（29/42）,66.67%（28/42）,61.90%（26/42）, respectively. The differences between the expression of NF-κB, MMP-9, integrinß1 in PNI group and non-PNI group were significant (P=0.005,P=0.011,P=0.001, respectively). Expression of NF-κB, MMP-9, integrin ß1 was correlated to that of GDNF(r=0.443, P=0.003; r=0.401, P=0.009; r=0.535, P=0.000, respectively). Expression of MMP-9 and integrin ß1 was positively correlated to that of NF-κB(r=0.501, P=0.001; r=0.429, P=0.005). Expression of MMP-9 was correlated positively to that of integrin ß1 (r=0.381, P=0.013). CONCLUSIONS：GDNF may increase the matrix-degrading and cell-adhesion of ACC in the process of PNI. NF-κB, MMP-9 and integrin ß1 involve in ACC cells invading nerves.