Objective To study the dynamic changes in the secretion of neurotransmitters glutamic acid(Glu)and γ-aminobutyric acid(GABA)in the central auditory brain area,in order to explore the effects of sodium salicy-late on different locations of the auditory pathway.Methods A total of 126 SD rats were injected intraperitoneally with salicylate,and were divided into 10 groups including injection groups for 1,2,4,8,and 24 hours,chronic in-jection groups for 3,7,and 14 days,and chronic recovery groups for 21 and 28 days with 6 rats in each group,as well as their corresponding blank control groups.Rats in each group were anesthetized and materials were collected for further use.High-performance liquid chromatography(HPLC)was performed to detect and compare the dynam-ic changes in the levels of Glu and GABA in the auditory cortex,inferior colliculus,cochlear nucleus,and hippocam-pus of the auditory center of rats in each group at different time points.Results Compared with the control group,within 24 hours of acute injection of salicylate,the Glu content in the auditory cortex reached the peak in 1 hour,and the hippocampus reached the peak at the 4th hour after injection,and then decreased slowly.The GABA con-tent in the four brain regions showed a slow upward trend in the chronic injection period,reached the peak on the 7th day,decreased and approached normal level on the 14th day,and basically returned to the normal level in the re-covery period.Conclusion These findings indicate that salicylate has a certain short-term excitatory and stimulating effect on the central auditory system.Under the mechanism of central plasticity,after long-term injection of salicy-late,the release of neurotransmitters reaches a new excitation/inhibition balance in the central area.Glu and GABA may each play a different role that may ultimately lead to the development of tinnitus.

Objective To study the dynamic changes in the secretion of neurotransmitters glutamic acid(Glu)and γ-aminobutyric acid(GABA)in the central auditory brain area,in order to explore the effects of sodium salicy-late on different locations of the auditory pathway.Methods A total of 126 SD rats were injected intraperitoneally with salicylate,and were divided into 10 groups including injection groups for 1,2,4,8,and 24 hours,chronic in-jection groups for 3,7,and 14 days,and chronic recovery groups for 21 and 28 days with 6 rats in each group,as well as their corresponding blank control groups.Rats in each group were anesthetized and materials were collected for further use.High-performance liquid chromatography(HPLC)was performed to detect and compare the dynam-ic changes in the levels of Glu and GABA in the auditory cortex,inferior colliculus,cochlear nucleus,and hippocam-pus of the auditory center of rats in each group at different time points.Results Compared with the control group,within 24 hours of acute injection of salicylate,the Glu content in the auditory cortex reached the peak in 1 hour,and the hippocampus reached the peak at the 4th hour after injection,and then decreased slowly.The GABA con-tent in the four brain regions showed a slow upward trend in the chronic injection period,reached the peak on the 7th day,decreased and approached normal level on the 14th day,and basically returned to the normal level in the re-covery period.Conclusion These findings indicate that salicylate has a certain short-term excitatory and stimulating effect on the central auditory system.Under the mechanism of central plasticity,after long-term injection of salicy-late,the release of neurotransmitters reaches a new excitation/inhibition balance in the central area.Glu and GABA may each play a different role that may ultimately lead to the development of tinnitus.

Objective To investigate the prevalence and correlates of depression in residents aged 15 and older in Hainan province.Methods Stratified multistage random sampling methods were utilized to identify 12 117 individuals (≥15 years old) from 59 villages (neighborhoods) in 24 towns (streets) within 6 counties (cities) in Hainan Province from September 2010 to November 2011.The subjects were screened with an expanded version of the General Health Questionnaire (GHQ-12) and the respondents were divided into three groups by high risk,moderate risk and low risk of mental disorder,followed by formal diagnosis according to the Structured Clinical Interview for DSM-IV-TR (SCID-I/P) by psychiatrists among 100％ subjects in group with high risk,40％ subjects in group with moderate risk and 10％ subjects in group with low risk.The adjusted rate,standardized rate,and 95％ confidence interval (95％CI) of the one-month and lifetime prevalence were also calculated among the 3 groups of individuals who were diagnosed with depressive disorder.The difference in whether they suffered depression was determined by the chi-squared test.Correlations to depressive disorder and the odds ratio (OR) were explored with multiple regression analysis.Results There were 97 cases of depressive disorders (1-month) and 166 cases of lifetime depressive disorders finally confirmed.The adjusted rate of 1-month prevalence was 1.38％ (95％CI:1.12-1.59) and the life-time adjusted prevalence rate was 2.80％ (95％CI:2.51-3.09).Female (OR=1.55,95％CI:1.12-2.14),mid-age(50-64 y,OR=1.84,95％CI:1.13-2.99),being divorced or living separated (OR=4.87,95％CI:1.86-12.73),suffering chronic diseases (OR=2.19,95％CI:1.56-3.07),and low family income were significantly associated with suffering depressive disorder.Conclusions The prevalence of the depressive disorder among residents aged 15 and older in Hainan province is lower than the nationwide prevalence.People who are female,mid-age,being divorced or not living with the partner,earning a low income,and suffering chronic diseases have more predisposition to develop the depressive disorder in Hainan province.

Objective To investigate the prevalence and correlates of depression in residents aged 15 and older in Hainan province.Methods Stratified multistage random sampling methods were utilized to identify 12 117 individuals (≥15 years old) from 59 villages (neighborhoods) in 24 towns (streets) within 6 counties (cities) in Hainan Province from September 2010 to November 2011.The subjects were screened with an expanded version of the General Health Questionnaire (GHQ-12) and the respondents were divided into three groups by high risk,moderate risk and low risk of mental disorder,followed by formal diagnosis according to the Structured Clinical Interview for DSM-IV-TR (SCID-I/P) by psychiatrists among 100％ subjects in group with high risk,40％ subjects in group with moderate risk and 10％ subjects in group with low risk.The adjusted rate,standardized rate,and 95％ confidence interval (95％CI) of the one-month and lifetime prevalence were also calculated among the 3 groups of individuals who were diagnosed with depressive disorder.The difference in whether they suffered depression was determined by the chi-squared test.Correlations to depressive disorder and the odds ratio (OR) were explored with multiple regression analysis.Results There were 97 cases of depressive disorders (1-month) and 166 cases of lifetime depressive disorders finally confirmed.The adjusted rate of 1-month prevalence was 1.38％ (95％CI:1.12-1.59) and the life-time adjusted prevalence rate was 2.80％ (95％CI:2.51-3.09).Female (OR=1.55,95％CI:1.12-2.14),mid-age(50-64 y,OR=1.84,95％CI:1.13-2.99),being divorced or living separated (OR=4.87,95％CI:1.86-12.73),suffering chronic diseases (OR=2.19,95％CI:1.56-3.07),and low family income were significantly associated with suffering depressive disorder.Conclusions The prevalence of the depressive disorder among residents aged 15 and older in Hainan province is lower than the nationwide prevalence.People who are female,mid-age,being divorced or not living with the partner,earning a low income,and suffering chronic diseases have more predisposition to develop the depressive disorder in Hainan province.

Objective: To explore the effects of bimodal intervention on the development of auditory and speech ability in the infants with unilateral cochlear implantation(CI). Methods: Total 35 bilateral profound sensorineural hearing loss infants with unilateral CI, aged 0.7 to 2.8 years old, were selected. The subjects were divided into two groups: the group with unilateral CI(cochlear implant alone, n= 15), and the bimodal group with CI and contralateral fitting hearing aid(n= 20). Their auditory and speech abilities were estimated at the different time points after switch-on(the 0th, 0.5th, 1st, 3rd, 6th, 12th, 18th, and 24th month, respectively) using Infant Toddler-Meaningful Auditory Integration Scale(IT-MAIS), Meaningful Use of Speech Scale(MUSS), Categories of Auditory Performance(CAP), and Speech Intelligibility Rating(SIR) scores. Results: The IT-MAIS scores of bimodal group after switch-on were higher than unilateral CI group(the 0.5th, 1st, 3rd, 6th, 12th, and 18th month), the statistical significances were identified at the 0.5th, 1st, 3rd, 6th, and 12th month, respectively(P<0.05). The CAP scores of bimodal group before CI operation and after switch-on(the 0.5th, 1st, 3rd, 6th, 12th, 18th and 24th month)were higher than unilateral CI group, the statistical significances were seen at the 3rd, 6th, 12th, 18th and 24th month after switch-on(P<0.05). The MUSS scores of bimodal group after switch-on were higher than unilateral CI group(the 1st, 3rd, 6th, 12th, 18th and 24th month), the statistical significances were found at the 12th, 18th and 24th month, respectively(P<0.05). The SIR scores of bimodal group after switch-on were higher than unilateral CI group(the 3rd, 6th, 12th, 18th and 24th month), and significant differences appeared at the 12th, 18th and 24th month after switch-on(P<0.05). Conclusion Bimodal intervention could be helpful to the development of auditory and speech ability of infants.

Objective To investigate the neural activity in the central auditory pathway by using a tinnitus an-imal model .Methods Twenty -four rats were randomly divided into the control ,acute salicylate treatment ,chronic salicylate treatment ,and recovery groups .The gap prepulse inhibition of acoustic startle test was used to confirm tinnitus -like behavior .After delivery of an intravenous bolus of fluorine -18 fluorodeoxyglucose (18F -FDG ) , small animal positron emission tomography scans were performed on rats .Results Only rats in chronic salicylate -treatment group showed evidence of experiencing tinnitus .The SUV ratios of the AC were significantly greater in the acute salicylate treatment group than in the control group (P<0 .01) ,suggesting relatively increased metabolism in the two brain regions of the rats in this group .The SUV ratios of the IC and AC (P<0 .01) ,but not of the CRB (P>0 .05) were greater in the chronic salicylate treatment group than in the control groups .There was a significant difference in whole brain SUVs between the control and acute salicylate treatment groups (P<0 .01) ,the whole brain SUVs in chronic salicylate treatment group were a little higher but showed no significant difference (P>0 .05) .There was no significant difference in the SUVs between the control and recovery groups (P>0 .05) .Conclu-sion These findings indicate that long -term salicylate administration induced tinnitus in rats and may have en-hanced neural activity corresponded to the up -regulated metabolic rate in our study .Alterations to neuroplasticity of the CNS may lead to tinnitus .

Objective To investigate the correlation between incidence rate of tinnitus and noise exposure time,age,hearing condition in noise exposure workers.Methods A total of 1 985 noise exposure workers (age between 20～60 years old;working length between 1 ～30 years) in a large dockyard were randomly selected as the subject of this study with 1 831 male workers and 154 female workers in average 36.3±8.25 years old.The average noise exposure time was 9.1±6.50 years and pure tone threshold of final candidates in sound-proofed environment was evaluated (at 0.25～8 kHz).The subjects were divided into four groups according to the subjective tinnitus level:mild tinnitus,moderate tinnitus,severe tinnitus and no tinnitus to analysis the correlation among incidence rate of tinnitus and noise exposure time,age,hearing condition,etc.Results Among all 1 985 subjects enrolled the occurrence rate of tinnitus was 20.55％ (408/1 985),with 367 acquired mild tinnitus(89.95％),39 acquired moderate tinnitus (9.56％) and 2 for severe tinnitus (0.49％).Mild tinnitus and moderate tinnitus showed a multi-step raising according to noise exposure time.Mild tinnitus increased continually with age while moderate tinnitus showed an accumulation in age group over 55 years old.Female was less likely to be annoyed by tinnitus than male.Conclusion Tinnitus can be early warning of auditory damage by noise exposure;older male group with longer noise exposure time is more vulnerable to tinnitus.Tinnitus acquired in noise environment is more likely to be mild.

OBJECTIVE To observe the changes of synaptic ultrastructures in the rat auditory center after long-term salicylate administration and to elucidate the role of neuroplasticity in some areas of the CNS and its involvement in tinnitus. METHODS The rats were divided into 4 groups: the control group, the acute treatment group, the chronic treatment group, and the recovery group. We investigated ultrastructural alterations in the synapses of inferior colliculus (IC), auditory center (AC) and cerebellum (CRB) by transmission electron microscopy. RESULTS There were more synaptic vesicles (tIC=-4. 61, tAC=-7. 00, P＜0. 01), with greater postsynaptic densities(tIC=-4. 72,P＜0. 01; tAc=-3. 15, P＜0. 05), longer synaptic active zone (tIC=-4. 89, tAC=-3. 48, P＜ 0. 01), and increased synaptic interface curvature (tIC=-2. 32, tAC=-3. 17, P＜0. 05) in the chronic treatment group, as compared with the control group. There were more synaptic vesicles but no other changes in the acute salicylate-treatment group(tIC=-10. 57, tAC=-8. 34, tCRB=-9. 18,P ＜0. 01). CONCLUSION These findings showed that long-term salicylate administration have induced synaptic ultrastructural changes in the IC and AC because of neuroplasticity. These structural changes may result in increased speed and efficacy of chemical synaptic transmission. Alterations to neuroplasticity of the auditory center pathway may lead to tinnitus.

Objective To investigate the relationship between pure -tone audiometry (PTA ) ,speech dis‐crimination abilities in quiet or in noise and the international outcome inventory for hearing aids (IOI-HA) in pres‐bycusis patients .Methods Twenty presbycusis subjects were tested in this study .Pure-tone audiometry (PTA) and speech discrimination threshold were obtained before being fitted with hearing aids .They weared hearig aids more than six months ,and pure-tone audiometry ,speech discrimination scores in quite(the level = 65 dB SPL) and in noise(signal to noise ratio = 10 dB) were carried out in sound field .A stepwise forward multiple-regression analysis was performed to investigate the impact of PTA and speech discrimination scores to IOI-HA .Results The PTAs before or after hearing aid fittings showed a negative association with IOI-HA ,while speech discrimination scores in quiet or in noise before or after hearing aid fittings showed a positive association with IOI-HA .Speech discrimination threshold in noise was identified as a single predictor of IOI-HA(P<0 .001) .Conclusion The relation between speech discrimination scores in noise and IOI-HA suggests that a poor score might limit the hearing aids outcome .The speech discrimination scores in noise help the clinicians predict the outcomes of hearing aid in real‐ities .