Comparisons of Supine Roll Test and Alternative Positional Tests in HC-BPPV Lateralization.

OBJECTIVE: The purpose of the study was to evaluate the efficiency of the supine roll test (SRT) and alternative positional tests (APTs) including the bow and lean test (BLT), pseudo-spontaneous nystagmus (PSN), and lying down nystagmus (LDN) to identify the affected side in horizontal canal benign paroxysmal positional vertigo (HC-BPPV). METHODS: In our prospective study, we performed a testing profile (PSN, BLT, LDN, SRT) on 59 HC-BPPV patients using videonystagmography. We compared the accuracy and sensitivity of these tests in HC-BPPV lateralization. Data from 30 healthy patients were collected as the control group. RESULTS: When performing positional tests, the elicited nystagmus coinciding with Ewald's second law was defined as a "positive response". In 44 patients with geotropic nystagmus, the rates of positive response in LDN, PSN, and BLT were 22/44 (50%), 19/44 (43%), and 18/44 (41%), respectively, while in 15 patients with apogeotropic nystagmus, the positive response rates of these three tests were 10/15 (66.7%), 9/15 (60%), and 4/15 (27.00%), respectively. The sensitivity of LDN (54.38%) was higher than that of PSN (47.37%) and BLT (38.60%) but lower than that of SRT (89.47%). Notably, the accuracy rate of PSN (71.8%) was higher than that of the other APTs. In 6 patients with symmetrical nysgtamus during the roll test, 5 patients showed a positive response in both LDN and BLT (83.34%), whereas 4 patients showed a positive response in PSN (66.67%). CONCLUSION: All positional tests are helpful for determining the affected side of HC-BPPV, but SRT carries the highest accuracy of lateralization followed by PSN.

CircSOX9 acts as a molecular sponge of miR-485-3p to promote the progression of nasopharyngeal carcinoma.

Circular RNA (circRNA) plays a vital role in the occurrence and development of nasopharyngeal carcinoma (NPC). However, the role of certain specific circRNAs in NPC are still unknown. In this study, collect tumor samples and adjacent normal tissues from clinical NPC patients and detect the expression of circSOX9 by qRT-PCR. Use nucleoplasmic separation analysis, RNase R digestion assay and FISH to detect the characteristics of circSOX9. After knocking down circSOX9, clone formation experiment and transwell assay were used to detect the proliferation and invasion ability of nasopharyngeal carcinoma cells HONE1 and CNE2, and western blot was used to further detect the level of epithelial-mesenchymal transition (EMT). Use the database to screen for possible downstream target genes and verify them with dual-luciferase experiments. Bioinformatics analysis showed that circSOX9 was significantly up-regulated in NPC, and its expression level was positively correlated with the malignant progression of cancer. Data from function gain or loss studies showed that decrease of circSOX9 inhibited the invasion and proliferation of HONE1 and CNE2 cell lines. Further analysis proved that miR-485-3p was the downstream target of circSOX9. The luciferase test showed that by acting as a molecular sponge of miR-485-3p, circSOX9 promotes the proliferation and invasion of NPC cells, while miR-485-3p can target the expression of SOX9. In conclusion, circSOX9 acts as an oncogene in the progression of NPC through miR-485-3p/SOX9, indicating that circSOX9 can be used as a potential therapeutic target and predictive marker for nasopharyngeal carcinoma.

Chaos and subharmonic bifurcations of a soft Duffing oscillator with a non-smooth periodic perturbation and harmonic excitation.

Chaotic dynamics and subharmonic bifurcations of a soft Duffing oscillator with a non-smooth periodic perturbation and a harmonic excitation are investigated analytically in this paper. With the Fourier series, the system is expanded to the equivalent smooth system, and chaos arising from heteroclinic intersections is studied with the Melnikov method. The chaotic feature on the system parameters is investigated in detail. Some new interesting dynamic phenomena, such as chaotic bands for some excitation frequencies, are presented. The relationship between the frequency range of chaotic bands and the amplitude of the excitation as well as the damping is obtained analytically. Particularly, for some system parameters satisfying a particular relationship, chaos cannot occur for any excitation amplitudes or frequencies. Subharmonic bifurcations are investigated with a subharmonic Melnikov method. It is analytically proved that the system may undergo chaotic motions through infinite or finite odd order subharmonic bifurcations. Numerical simulations are given to verify the chaos threshold and revolution from subharmonic bifurcations to chaos obtained by analytical methods.

Functional Magnetic Resonance Imaging Reveals Early Connectivity Changes in the Auditory and Vestibular Cortices in Idiopathic Sudden Sensorineural Hearing Loss With Vertigo: A Pilot Study.

The underlying pathophysiology of idiopathic sudden sensorineural hearing loss (ISSNHL) with vertigo has yet to be identified. The aims of the current study were (1) to elucidate whether there are functional changes of the intrinsic brain activity in the auditory and vestibular cortices of the ISSNHL patients with vertigo using resting-state functional magnetic resonance imaging (rs-fMRI) and (2) whether the connectivity alterations are related to the clinical performance associated with ISSNHL with vertigo. Twelve ISSNHL patients with vertigo, eleven ISSNHL patients without vertigo and eleven healthy subjects were enrolled in this study. Rs-fMRI data of auditory and vestibular cortices was extracted and regional homogeneity (ReHo) and seed-based functional connectivity (FC) were evaluated; the chi-square test, the ANOVA and the Bonferroni multiple comparison tests were performed. Significantly decreased ReHo in the ipsilateral auditory cortex, as well as increased FC between the inferior parietal gyrus and the auditory cortex were found in the ISSNHL with vertigo groups. These findings contribute to a characterization of early plastic changes in ISSNHL patients with vertigo and cultivate new insights for the etiology research.

Expression of α2-Na/K-ATPase in C57BL/6J Mice Inner Ear and Its Relationship with Age-related Hearing Loss.

K+ cycling in the cochlea is critical to maintain hearing. Many sodium-potassium pumps are proved to participate in K+ cycling, such as Na/K-ATPase. The α2-Na/K-ATPase is an important isoform of Na/K-ATPase. The expression of α2-Na/K-ATPase in the cochlea is not clear. In this study, we used C57BL/6 mice as a model of presbycusis and implemented immunohistochemistry staining and quantitative real time-PCR, and the α2-Na/K-ATPase expression pattern was confirmed in the inner ear. It was found α2-Na/K-ATPase was expressed widely in cochlea and its mRNA and protein expression was gradually reduced with aging (4-, 14-, 26- and 48-weeks old mice). We suspected that, the down-regulation of α2-Na/K-ATPase expression might be associated with the remodeling of K+ cycling, degeneration of morphological structure and decrease of hearing function in aging C57 mice. In conclusion, we speculated that the reduction of α2-Na/K-ATPase might play an important role in the pathogenesis of age-related hearing loss.

A Comparison of Triamcinolone Acetonide Econazole Cream and Nystatin Suspension in Treatment of Otomycosis.

OBJECTIVES/HYPOTHESIS: To compare the efficacy and adverse effects of triamcinolone acetonide econazole cream and nystatin suspension in the treatment of otomycosis, and to determine the clinical features, predisposing factors, and etiology of otomycosis. STUDY DESIGN: A prospective study. METHODS: A prospective clinical trial was conducted on 786 patients diagnosed with otomycosis. The study population was randomly divided into two treatment groups of triamcinolone acetonide econazole cream (TAEC) and nystatin suspension in a 1:1 ratio. After clearing all fungal deposits in the external auditory canal, the antimycotic drugs were locally applied for at least 2 weeks. The efficacy and adverse effects were compared between the two antifungal reagents by statistical analysis. Meanwhile, patient clinical data were collected to find out the clinical features, predisposing factors, and etiology. RESULTS: Pruritis was the most common symptom and Aspergillus niger was the leading fungal pathogen. There was high association (44.5%) of otomycosis with a history of unclean ear picking. The cure rate was 97.6% in the TAEC group and 73.5% in the nystatin group (P < .01). Treatment with TAEC resulted in 2.4% of patients complaining of discomforts (irritant dermatitis, otalgia, or headache) versus 59.8% of patients complaining discomforts treated with nystatin (P < .01). The residue rate of antifungals was 1.9% in the TAEC group and 89.9% in the nystatin group (P < .01) at the end of treatment. CONCLUSIONS: Thoroughly cleaning of the external auditory canal followed by local use of TAEC under endotoscope is an effective, convenient, and well-tolerated treatment for otomycosis. LEVEL OF EVIDENCE: 1 Laryngoscope, 131:E1640-E1646, 2021.

[Short-term postoperative outcome of laser-assisted stapedotomy in patients with otosclerosis].

Objective:To assess the short-term efficacy of laser-assisted stapedotomy in patients with otosclerosis. Method:The clinical data of twenty-one patients with otosclerosis who underwent laser-assisted stapedotomy were retrospectively analyzed . Preoperative and 3-month postoperative standardized audiometric evaluations were carried out in all patients. The occurrence of surgical complications was observed. Result:The mean preoperative and postoperative air conduction （AC） thresholds were （58.2±12.7） dB HL and （43.0±23.1）dB HL respectively; the postoperative AC threshold decreased by 15.2 dB HL which was statistically significant at 0.5, 1, 2, and 4 kHz （P<0.01）. The mean preoperative and postoperative bone conduction （BC） thresholds were （31.4±10.3）dB HL and （33.3±16.6）dB HL, and there was not significant difference between them as well as BC thresholds at each frequency. Overclosure >10 dB HL was occured in 3 ears （14.3%） while sensorineural hearing loss>10 dB HL was found in 2 ears （9.5%）. The mean ABG decreased by 17.4 dB HL （P<0.01） from preoperative （27.0±9.1） dB HL to postoperative （9.6±9.9） dB HL, and the ABG at each frequency had significant decrease. Fourteen ears （66.7%） had postoperative ABG of ≤10 dB HL while 18 ears （85.7%） had postoperative ABG of ≤20 dB HL. Sensorineural hearing loss occurred in 2 ears （9.5%） after surgery, tinnitus in 15 ears （71.4%） and vertigo in 3 ears （14.3%）. But all were relieved on the third day after operation. Conclusion:Laser-assisted stapedotomy is a safe and effective treatment of otosclerosis. Although BC thresholds was slightly increased after surgery, it did not affect the overall hearing outcomes.

Expression Patterns and Implications of LaminB1 in Rat Cochleae.

LaminB1, a major component of the nuclear lamina, is a potent regulator of cellular proliferation and senescence and also known to be essential for neuronal migration and brain development. However, the expression patterns of LaminB1 in the rat cochleae are still not fully revealed. Utilizing immunofluorescence, Western blotting, and quantitative real-time PCR, we identified the distribution and expression of LaminB1 in the rat cochleae. Immunofluorescence staining indicated that LaminB1 was mainly localized in the auditory hair cells (HCs), spiral ganglion cells (SGC), stria vascularis (STV, including spiral ligament), Reissner's membrane (RM), and limbus laminae spiralis (LLS). Western blotting analysis illustrated that the distribution of LaminB1 in rat cochleae was characterized by tissue specificity. The LaminB1 protein was expressed more in SGC and basilar membrane (BM) than in STV. Meanwhile, the mRNA expression of LaminB1 displayed difference in cochlear tissues. These observations preliminarily revealed the expression patterns of LaminB1, providing a theoretical basis for further study on the role of LaminB1 in auditory function.

Sudden Sensorineural Hearing Loss in Children: Clinical Characteristics, Etiology, Treatment Outcomes, and Prognostic Factors.

OBJECTIVE: To investigate the clinical characteristics, etiology, treatment outcomes, and prognostic factors of sudden sensorineural hearing loss (SSNHL) in children to guide the clinical diagnosis and treatment of SSNHL in the pediatric population. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: Patients diagnosed with SSNHL from November 2011 to December 2017 with relatively complete clinical data. INTERVENTION: Diagnosis and systemic treatment of SSNHL. MAIN OUTCOME MEASURES: Patients' clinical characteristics, etiology, laboratory tests, imaging, pure-tone audiometry at admission, and discharge were analyzed. RESULTS: A total of 25 children and 149 adults with SSNHL were included. Recent or previous viral infection rates (81.8%) and fasting blood glucose level (5.23 + 1.47 mmol/L) in children with SSNHL were lower than those in adult SSNHL patients (p = 0.033, p = 0.033). Autoimmune abnormalities (90.0%) and plasma fibrinogen abnormalities (27.3%) were higher in children with SSNHL than those in adult SSNHL patients (40.0%, 8.8%, respectively, p < 0.05). The recovery rate in children (38.4%) with SSNHL is comparable to that in adults (22.6%), but children have a higher complete rate compared to adults (26.9%, 11.3%, respectively, p < 0.05). Children with a profound audiometric curve had a worse prognosis in comparison to other types of audiometric curves (p = 0.041). CONCLUSIONS: Children with SSNHL have a lower rate of viral infection in comparison to adults with SSNHL. Fasting blood glucose levels, complement C3, C4, and fibrinogen may be closely related to childhood SSNHL. The recovery rate in children with SSNHL is comparable to that in adults, but children have a higher complete rate compared to adults. A profound hearing curve is an unfavorable prognostic factor in both children and adults with SSNHL.

Predictive factors for complications associated with penetrated fish bones outside the upper gastrointestinal tract.

PURPOSE: To investigate predictive risk factors for complications associated with migrating fish bones in the surrounding tissue of upper gastrointestinal tract. METHODS: A retrospective analysis over 12 years was conducted of 45 cases of buried fish bones in the surrounding tissue of upper gastrointestinal tract with complications. Meanwhile, a control group, including 39 cases of prolonged buried fish bones in the surrounding tissue of upper gastrointestinal tract without complications, was set. Patient clinical data were collected and analyzed to predict the risk factors for complications. RESULTS: The results of Chi-square test and univariate analysis both showed a significant difference in length of fish bone (> 2 cm), a history of concurrent medical illness (diabetes mellitus and renal hypofunction), symptoms (medium or heavy pain and dysphagia), and duration of significant symptoms (> 7 days) between the complication group and non-complication group. Multivariate analysis further identified length (> 2 cm), diabetes mellitus, medium or heavy pain, dysphagia, and duration of significant symptoms (> 7 days) as independent risk factors for complications. CONCLUSIONS: The consequences of fish bones migrating outside the upper gastrointestinal tract are various in different people. Awareness should be raised when encountering a patient ingesting a long fish bone, having a history of diabetes mellitus, presenting with significant discomforts, or these discomforts lasting for a long time. This study will help practitioners counsel their patients on the risks and `benefits of surgery versus observation of this condition.

Transauricular vagus nerve stimulation at auricular acupoints Kindey (CO10), Yidan (CO11), Liver (CO12) and Shenmen (TF4) can induce auditory and limbic cortices activation measured by fMRI.

The purpose of this study was to explore the central mechanism of transauricular vagus nerve stimulation (taVNS) to human by fMRI and to find a suitable taVNS site for potential tinnitus treatment. 24 healthy subjects aged between 28 and 38 years were enrolled in the experiment. 8 subjects were stimulated in the auricular acupoints Kindey (CO10), Yidan (CO11), Liver (CO12) and Shenmen (TF4) in the left ear, 8 subjects were stimulated at the anterior wall of the auditory canal and left lower limb as an anterior stimulation group; 8 persons who were arranged in a sham group received taVNS at the left ear lobe and tail of the helix. Functional magnetic resonance imaging (fMRI) data from the cortices was collected and an Alphasim analysis was performed. We found that taVNS at auricular acupoints CO10-12, TF4 can instantly and effectively generate blood oxygenation level dependent (BOLD) signal changes in the prefrontal, auditory and limbic cortices of healthy subjects by fMRI. When comparing the acupoints group and the sham group in the left brain, the signals from the prefrontal cortex, the auditory ascending pathway including superior temporal gyrus, middle temporal gyrus, thalamus and limbic system regions such as putamen, caudate, posterior cingulate cortex, amygdala and parahippocampal gyrus were increased under our stimulation. The difference of the BOLD signal in the left brain between acupoints group and anterior group was in the superior temporal gyrus. We could also find signal differences in several regions of right brain among the groups. In conclusion, taVNS at acupoints CO10-12, TF4 could activate the prefrontal, auditory and limbic cortices of healthy brain and this scheme could be a promising tool for tinnitus treatment.

Elevated expression of yes­associated protein is associated with the malignant status and prognosis of laryngeal squamous cell carcinoma.

Previous studies have demonstrated that elevated yes­associated protein (YAP) expression is associated with tumor aggression and poor prognosis in various types of human cancer. However, the clinicopathological significance and the prognostic value of YAP in laryngeal squamous cell carcinoma (LSCC) is unknown. The aim of the present study was to identify the expression pattern and prognostic significance of YAP in patients with LSCC. YAP mRNA and protein expression levels were examined in fresh and archived LSCC samples using the reverse transcription­quantitative polymerase chain reaction, immunohistochemistry (IHC) and western blotting. The association between YAP expression levels with the malignant status and prognosis of patients with LSCC was analyzed. Upregulated protein and mRNA expression levels of YAP were detected in LSCC tissues compared with paired healthy surgical margin tissues. Positive expression of YAP was identified in 84/121 (69.4%) LSCC tissues and in 4/30 (13.3%) healthy surgical margin tissues by IHC. Positive YAP protein expression was significantly associated with clinical stage, TNM classification, lymph node metastasis and differentiated degree. Patients with positive YAP expression exhibited a significantly decreased overall survival time compared with patients with negative YAP expression (P=0.0002). Multivariate analysis indicated that the level of YAP expression was an independent prognostic factor for poor survival in patients with LSCC (P=0.012). In conclusion, the expression level of YAP was significantly increased in LSCC and associated with the malignant status of LSCC. Therefore, YAP may represent a novel biomarker for predicting the prognosis of patients with LSCC.

Downregulation of inwardly rectifying potassium channel 5.1 expression in C57BL/6J cochlear lateral wall.

Age-related hearing loss (AHL) is one of the most common sensory disorders among elderly persons. The inwardly rectifying potassium channel 5.1 (Kir5.1) plays a vital role in regulating cochlear K(+) circulation which is necessary for normal hearing. The distribution of Kir5.1 in C57BL/6J mice cochleae, and the relationship between the expression of Kir5.1 and the etiology of AHL were investigated. Forty C57BL/6J mice were randomly divided into four groups at 4, 12, 24 and 52 weeks of age respectively. The location of Kir5.1 was detected by immunofluorescence technique. The mRNA and protein expression of Kir5.1 was evaluated in mice cochleae using real-time polymerase-chain reactions (RT-PCR) and Western blotting respectively. Kir5.1 was detected in the type II and IV fibrocytes of the spiral ligament in the cochlear lateral wall of C57BL/6J mice. The expression levels of Kir5.1 mRNA and protein in the cochleae of aging C57BL/6J mice were down-regulated. It was suggested that the age-related decreased expression of Kir5.1 in the lateral wall of C57BL/6J mice was associated with hearing loss. Our results indicated that Kir5.1 may play an important role in the pathogenesis of AHL.

Down-regulation of the large conductance Ca(2+)-activated K(+) channel expression in C57BL/6J cochlea.

CONCLUSION: The large conductance Ca(2+)-activated K(+ )channels (BK) expression is decreased in the cochleae of age-related hearing loss (AHL) mice. BK channel may be associated with AHL. OBJECTIVE: AHL is the most common among elderly persons. BK channels act as sensors for membrane voltage and intracellular Ca(2+ )and are essential for hearing. To investigate the distribution of BK channel in the cochleae of C57BL/6J mice, and the relationship between the expression of BK channel and the etiology of AHL. METHODS: BK expression was studied in the cochleae of C57BL/6J mice at various ages (4, 12, 26, 52 weeks). The expressions of BK at the protein and mRNA levels were detected by immunofluorescence technique, western blot and quantitative real time PCR. RESULTS: In comparison with 4-week-old mice, BK expressions in the cochleae at 12, 26 and 52 weeks of age were significantly and gradually decreased at both the protein and the mRNA levels. The immunofluorescence technique showed the BK channel was located in the hair cells and cells of the spiral ganglion, spiral ligament and stria vascularis and its expression also decreased with aging.

Evaluation of cochlear nerve diameter and cross-sectional area in ANSD patients by 3.0-Tesla MRI.

CONCLUSIONS: The size of cochlear nerve (CN) is atrophic in adult auditory neuropathy spectrum disorder (ANSD) patients compared with non-ANSD sensorineural hearing loss (SNHL) patients and normal hearing subjects, and CN deficiency is one of the lesions for ANSD patients. OBJECTIVES: To evaluate the dimensions of CN in adult ANSD patients on magnetic resonance imaging (MRI) and confirm the hypothesis that CN deficiency is one of the lesions for ANSD patients. METHODS: Medical records and MRI of 24 adult ANSD patients reviewed retrospectively and 20 non-ANSD SNHL and 24 volunteers with normal hearing were recruited as control groups. The long diameter (LD), short diameter (SD), and cross-sectional area (CSA) of CN and facial nerve (FN) were measured. RESULTS: Among the 24 ANSD patients, this study was able to reconstruct and measure the CN of 91.7% (22/24, total 43 ears) of patients and FN of 83.3% (20/24, total 38 ears) of patients. The mean values and standard deviations of LD, SD, and CSA of CN in ANSD patients were 0.65 ± 0.20 mm, 0.44 ± 0.15 mm, and 0.30 ± 0.19 mm(2), respectively. They were significantly smaller in ANSD patients than in control groups (p < 0.001).

Cortical Bone Mineralization in the Human Femoral Neck in Cases and Controls from Synchrotron Radiation Study.

To compare the degree and distribution of mineralization in femoral neck cortex from 23 women with hip fractures (age 65-96 years) and 17 female controls (age 72-103 years), we obtained 3D data by synchrotron radiation microtomography (SRµCT). Variables were degree of mineralization of bone (DMB) in total cortex (cDMBSRMEAN), osteons (oDMBSRMEAN), and pure interstitial tissue (intDMBSRMEAN). The cortex on SRµCT images was divided into nine to twelve 50-µm zones from the periosteum to the endosteum; cDMBSRMEAN, oDMBSRMEAN, and intDMBSRMEAN were measured in each zone. We used descriptive statistics and t tests, general linear model analyses to compare DMBSR values across zones and individuals, one-way analysis of variance for within-group comparisons of zones. In patients, the variance of mineral content value was not different than in controls, but mean values of degree of mineralization varied across zones. These cross-sectional data suggest that bone fragility may be related to a greater heterogeneity of the distribution of mineralization in femoral neck cortex.

17-DMAG induces Hsp70 and protects the auditory hair cells from kanamycin ototoxicity in vitro.

Heat shock protein 70 (Hsp70) has been known to be able to play a protective role in the cochlea. The aim of this study was to investigate whether geldanamycin hydrosoluble derivative 17-(dimethylaminoethylamino)-17-demethoxygeldanamycin (17-DMAG) has the ability to induce Hsp70 up-regulation to protect hair cells from kanamycin-induced ototoxicity in vitro. The organ of Corti (OC) explants were isolated from mice at postnatal day 3-5. Then, the explants were exposed to kanamycin with or without pre-incubation with 17-DMAG. The expression of Hsp70 was assessed by reverse transcription-quantitative polymerase chain reaction, ELISA, and immunofluorescent staining. The surviving hair cells were examined by phalloidin labeling and were counted. We found that Hsp70 expression in the explants after pre-incubation with 17-DMAG was significantly increased at both mRNA and protein levels. Immunofluorescent staining showed that Hsp70 was mainly located in the auditory hair cells. Compared with kanamycin group, the loss of hair cells was inhibited significantly in 17-DMAG+kanamycin group. Our study demonstrated that 17-DMAG induces Hsp70 in the hair cells, and has a significant protective effect against kanamycin ototoxicity in vitro. 17-DMAG has the possibility to be a safe and effective anti-ototoxic drug.

[Age-related expression of plasma membrane Ca(2+) -ATPase isoform 2 in the cochleas of C57BL/6J mice].

OBJECTIVE: To investigate the location and distribution of plasma membrane Ca²âº -ATPase isoform 2(PMCA2) in the cochleas of C57BL/6J mice at various ages (4w, 14w, 22w, 45w), and to reveal the relationship of PMCA2 and age-related hearing loss (AHL). METHODS: The distribution of PMCA2 in the cochleas of C57BL/6J mice was detected by immunohistochemistry at various ages (4w, 14w, 22w, 45w). Real-time polymerase chain reaction (Rt-PCR) was used to detect the level of PMCA2 mRNA in the cochleas of C57BL/6J mice at the ages of 4, 14, 22 and 45 weeks old respectively. Using SPSS17.0 software for statistical analysis. RESULTS: PMCA2 was mainly located in the hear cells, stria vascularis, and spiral ganglion cells. Faint labeling of PMCA2 was also observed in spiral ligament. Hair cells missed and the number of spiral ganglion cells reduced with age. Expression of PMCA2 in the cochleas of C57BL/6J mice also showed age-related decreasing. The results of Rt-PCR demonstrated the expression of mRNA of gene (Atp2b2) at 14 weeks age was significantly less than 4 week-old mice cochlears (P<0.05). The expression of mRNA of gene (Atp2b2) at 22 weeks age was significantly less than 14 week-old mice cochlears (P<0.05). The expression of mRNA of gene (Atp2b2) at 45 weeks age was significantly less than 14 week-old mice cochlears (P<0.01). CONCLUSIONS: PMCA2 is mainly located in the hear cells, stria vascularis, and spiral ganglion cells. Faint labeling of PMCA2 is also observed in spiral ligament. The expression of PMCA2 demonstrates an age-related decrease with age. The mRNA expression level of PMCA2 gene(Atp2b2) in the cochleas of C57BL/6J mice displayed an age-related decrease. PMCA2 transporters may play a critical role in maintaining the normal morphology of the inner ear and it may be related to AHL.

Age-related change in the expression of NKCC1 in the cochlear lateral wall of C57BL/6J mice.

CONCLUSIONS: Na(+)-K(+)-2Cl(-) co-transporter isoform 1 (NKCC1) mRNA and protein decrease with increasing age in the cochlear lateral wall of C57BL/6J (C57) mice. The down-regulation of NKCC1 may influence the K(+) transport efficiency and the homeostasis of ion transport cells, and cause the irreversible damage of cochlear cells in old C57 mice. Our results indicate that NKCC1 may play an important role in the pathogenesis of age-related hearing loss (AHL). OBJECTIVES: The aim of the present study was to investigate the relationship between the functional expression of NKCC1 transporter and the etiology of AHL. METHODS: C57 mice were used and randomly divided into four groups according to age (4 weeks, 14 weeks, 26 weeks, and 52 weeks). Immunofluorescence technique, quantitative real-time PCR, and western blot were applied to detect the expression of NKCC1 in the cochlear lateral wall of C57 mice at the various ages. RESULTS: In all four groups, the expression of NKCC1 was observed in the stria vascularis and type II fibrocytes of the spiral ligament. Also, the expression of NKCC1 appeared to decrease with age at both the transcriptional level and the protein level.

[Electrocochleography in the diagnosis of Meniere's disease].

OBJECTIVE: To evaluate clinical value of electrocochleography in diagnosing the Meniere's disease. METHOD: Patients were saperated as having definite, probable and possible Meniere's disease according to the 1995 AAOHNS guidelines. Then set the probable and possible Meniere's disease as a suspected group. We used four different stimulus (clicks, 1000 Hz tone burst, 2000 Hz and 4000 Hz tone burst) to record electrocochleo-graphy. Those patients in each group received electrocochleography examination, and summating potential (SP)/action potential (AP) ratios were calculated. A prolonged action potential latency shift (AP shift) evoked by rarefaction and condensation clicks was also measured. RESULT: The click SP/AP positive rate in definite Meniere's disease group was 41.2%, tone burst at 1,000 Hz. 2,000 Hz,4,000 Hz were respectively 80.4%, 72.5%, 37.3%, AP shift positive rate was 45.1%. Using McNemar test, the positive rate of tone burst 1000 Hz (chi2 = 15.04, P < 0.01) and that of tone burst 2,000 Hz (chi2 = 8.65, P < 0.01) were statistically significant different when compared with that of click SP/AP, besides the tone burst at 1,000 Hz yielded has the highest sensitivity. The click SP/AP positive rate in suspected group and definite group were respectively 12% and 45.1% (chi2 = 6.610, P < 0.05) and AP shift positive rate of them were respectively 8.0% and 41.2% (chi2 = 10.460, P < 0.01). By chis-quare test, the positive rates of click SP/AP and AP shift between these two groups were statistically significant different. CONCLUSION: Electrocochleography is a reliable test in the diagnosis of Meniere's disease. Compared with clicks, tone burst significantly has a higher sensitivity, especially at 1000Hz and 2000Hz frequencies. A prolonged action potential latency shift evoked by rarefaction and condensation clicks is also a useful addition to diagnosis Meniere' disease.