Expression of Nrf2 and Its Related Factors in the Cochlea of Rats with Noise Induced Hearing Loss / 听力学及言语疾病杂志

Objective To study the expression of Nuclear factor E2 related factor 2 (Nrf2) ,Superoxide Dis‐mutas 1 (SOD1) ,and Heme Oxygenase- 1( HO -1) factors related to Nrf2 signaling pathway in noise-induced cochlear injury of rats .Methods A total of 30 SD rats were randomly and equally assigned into the following 2 groups :noise group and normal control group .The rats in noise group were exposed to an 115 dB SPL continuous steady white noise for 12 hours ,then 1 day ,3 days ,and 7 days later ,the rats receveid the ABR and DPOAE testing after noise exposure .Both RT -PCR and Peggy Sue trace protein detection techniques were used to detect gene ex‐pression in Nrf2 /Keapl-ARE signaling pathway and the protein levels by cochlear tissue sampling after noise ex‐posure 7 days later .Results The ABR thresholds in the noise group was higher than those of in normal control group after noise exposure 1 ,3 ,and 7 days later (P<0 .05) .The DPOAE values of noise group were significantly lower than those of normal control group (P<0 .05) .The up -regulation of expression of Nrf2 ,SOD1 ,HO -1 mRNA(1 .11 ± 0 .05 ,1 .45 ± 0 .12 ,1 .15 ± 0 .03) in noise group were higher than those of in the normal control group after noise exposure 7 days later (1 .00 ± 0 .02 ,1 .10 ± 0 .12 ,0 .92 ± 0 .08) ,and the differences were statistically sig‐nificant (P<0 .05) .And in Peggy Sue trace detection system ,we also found SOD1 ,HO -1 protein levels in noise group were higher than those of in normal control group .Conclusion After the noise -induced cochlear injury in rat ,Nrf2 expression in the cochlea increased and up-regulatd expression of downstream gene and protein content such as antioxidant enzymes SOD1 and HO-1gene by regulating Nrf2 /Keapl-ARE signaling pathway ,which may be involved in protection against oxidative stress injury in noise-induced cochlear injury of rat .

Effect of retreatment on the end-stage sudden deafness.

Microcirculatory disturbance of inner ear is probably one of the important etiological factors of sudden deafness. The purpose of this study was to evaluate the effect of retreatment on the end-stage sudden deafness. For this purpose, the patients who met with the criteria for sudden deafness and showed poor response to conventional therapy over 2 months were assigned randomly to the retreatment group. Pure tone audiometry was conducted before and after retreatment among the 103 patients (112 ears). Sodium bicarbonate and dexamethasone were injected by intravenous drip for 2 days and batroxobin 5BU for 6 days. Data were analyzed using analysis of variance and t test to determine the efficacy of retreatment. These data show that the efficacy rate in retreatment group was 46.43% and the difference between before and after retreatment was significant (P < 0.01). It was, therefore, concluded that retreatment of the end-stage sudden deafness could improve the audition of the patients and should be valuable in clinics. In this regard, the combination of sodium bicarbonate and dexamethasone proved a rational therapeutic regimen for the end-stage sudden deafness. However, further large-size multicenter studies will be required for independent validation of these findings.

The Clinical Observation the Effects of the Re-Therapeutic on the Later Stage of Sudden Deafness / 听力学及言语疾病杂志

Objective To observe the effects of the re-therapeutic on later stage of sudden deafness.Methods Patients who met the criteria for sudden deafness and showed poor response tO conventional therapy over two months were recruited and assigned randomly for re-therapy.The pure tone audiometry was conducted before and after re-treatment in 103 patients(112 ears).Sodium bicarbonate and dexamethasone were iniected by intravenous drip for two days and batroxobin 5 BU for 6 days.Statistics were made in the effecency of the re-treatment.Results The effective rate of re-treatment group was 46.43% and the difference was significant before and after retreatment(P<0.01).Conclusion Combined use of sodium bicarbonate dexamethasone and batroxobin is effective in re-treating later sudden deafness.