Objective To compare the characteristics of the SP-AP compound wave elicited by click and tone pip.Methods The electrocoehleogram was recorded with round window electrode,and waves were elicited by click and tone pips,respectively.Results The SP-AP compound waves were elicited 1,2,3,4 and 8 kHz tone pip and click.The amplitude of SP at each frequency was-13.56±8.7,-16.61±10.53,-10.13±14.75,-3.71±14.49,-2.99±5.4 and -4.44±10.81 μv,respectively.Conclusion Tone pip at 1,2,3,4,8 kHz can elicit SP,and produce frequency specific SP wave.This is helpful to identify the lesion site of auditory neuropathy.

Objective To explore the relationship between the duration of tone pip with Blackman envelop and morphology or latency of auditory brainstem responses.Methods ABRs were recorded using 0.5,1,2,4 and 8 kHz tone pips with Blackman envelope at different intervals.Results The longer the duration of stimulus was,the better the frequency specificity of stimulus was.However,the ABR morphology were affected and the latencies of wave Ⅲ were prolonged.Conclusion When using tone pips to evokes ABR,stimuli should be well considered in order to produce better frequency specificity and transient state.

0.05).② The VMCD group had a higher speech recognition threshold than the healthy aged group and the ARCD group(P

AIM: To quantify cyclooxygenase - 2 (COX - 2) mRNA in carcinoma of larynx and evaluate the correlation between the quantity of COX - 2 mRNA and clinical staging or histological grade. METHODS: The expression of COX - 2mRNA in 30 cases of carcinoma of larynx tissue and adjacent non - cancerous tissues were evaluated by PCR, which includes a fluorescence dye , SYBR green Ⅰ , and the sequence specific primer. The GAPDH was used as control. RESULTS: The specificity of products was proved to be COX - 2 and GAPDH by the analysis of the melting curve of the amplified products and agarose gel electrophoresis. The expression of COX - 2 mRNA was detected in all cancerous tissues of 30 patients (100%), but only in 12 adjacent non - cancerous tissues of 30 patients (40%). The NCOX value of carcinoma of larynx tissue and adjacent non - cancerous tissues was 16.54 ± 13.27 and 9.24 ± 6.91, respectively, and the expression levels of COX- 2 mRNA elevated significantly in laryngeal squamous cell carcinoma tissue and there were significant correlation between the expression levels of COX - 2mRNA and clinical stage or histological grade. CONCLUSION: The expression of COX - 2 mRNA in carcinoma of larynx can be determined by real - time PCR technique. An increase in COX - 2 mRNA may be associated with carcinogenesis of carcinoma of larynx, and it may be useful as a biomarker in laryngeal cancer.

Objective To study the distribution of the gap conjunction and connexin(Cx)26 and 32 in inner ear of guinea pig. Methods We investigated expression and distribution of gap conjunction and Cx 26 and Cx 32 in cochlea of guinea by immunohistochemistry, RT-PCR and electron microscopy. Results T The gap conjunction was easily seen between hair cells and supporting cells in cochlea of guinea pigs. Cx26 was widely distributed in the stria vascularis, the spiral ligament and between the supporting cells, and Cx32 appeared mainly among supporting cells, in the stria vascularris. Conclusion There exist lots of gap conjunctions in inner ear of guinea pig. Two kinds of connexins can be seen in guinea pig's cochlea, and the Cx 26 plays more important role than other Cx.

Objective To investigate whether apoptosis is invovled in the immune response of inner ear,and relation between the signal transduction of Caspase-3 and apoptosis. Methods Sixteen healthy,female guinea pigs were employed in this study. The animals in the experiment group were sensitized systematically with keyhole limpet hemocyanin(KLH),then were inoculated in inner ear with the same antigen, and the animals in the control group were injected with the same volume of PBS. The animals were sacrificed at the 5th day after inner ear vaccination. Paraffin sections of cochleas from animals were prepared, TUNEL assay was used to detect apoptotic cells in inner ears, and immunohistochemical method was applied to detect the expression of Caspase-3 in inner ears. Results TUNEL-positive cells are found in the inner ears of the experiment group, but did not in the inner ears of the control group except for a few TUNEL-positive cells in the supporting cells, the stria vascular cells and the spiral ganglion cells. The high expression of Caspase-3 could be detected in the inner ears of the experiment group, but no positive cells of Caspase-3 were found in the inner ears of the control group. Conclusion Apoptosis could be induced by the immune response of inner ear, and Caspase-3 cascade may be involved in the course of apoptosis.

Objective To investigate the appropri ate changes of the central masking effect(CME) when there were pathologies in d ifferent segment of auditory pathway,so as to give some instructions in cli nical masking test. Methods We tested the subjects with one ear normal and th e other ear diseased. The diseased ears included conductive deafness in 30 ca ses?sensory deafness in 27 cases and retrocochlear deafness in 7 cases. Results The pure conductive deafness had very little effect on CME; secretory otistis media and chronic suppurative otistis medi a made CME lower than normal due to the secondary cochlear impairment .When su dden deafness companied with vertigo,CME appeared much higher than the normal and appeared great difference individually;but CME appeared lower than normal at other kinds of cochlear deafness ears.CME appeared differently at retrocochlear deafness ears. Conclusion Audiometry results should be corrected when th e masker higher than 40 dB EM,because the masker can make the CME higher than 5 dB in the conductive impairment ears.In the sudden de afness companied with vertigo ears,CMEs were too high and too individually to fi nd a suitable correction for PTT.Insert earphone should be used in measuring the air-conduction PTT,and bone-conduction PTT test might be given up.

AIM: To quantify cyclooxygenase-2 (COX-2) mRNA in carcinoma of larynx and evaluate the correlation between the quantity of COX-2 mRNA and clinical staging or histological grade. METHODS: The expression of COX-2 mRNA in 30 cases of carcinoma of larynx tissue and adjacent non-cancerous tissues were evaluated by PCR, which includes a fluorescence dye , SYBR green Ⅰ, and the sequence specific primer. The GAPDH was used as control. RESULTS: The specificity of products was proved to be COX-2 and GAPDH by the analysis of the melting curve of the amplified products and agarose gel electrophoresis. The expression of COX-2 mRNA was detected in all cancerous tissues of 30 patients (100%), but only in 12 adjacent non-cancerous tissues of 30 patients (40%). The N_ COX value of carcinoma of larynx tissue and adjacent non-cancerous tissues was 16.54?13.27 and 9.24?6.91, respectively, and the expression levels of COX-2 mRNA elevated significantly in laryngeal squamous cell carcinoma tissue and there were significant correlation between the expression levels of COX-2 mRNA and clinical stage or histological grade. CONCLUSION: The expression of COX-2 mRNA in carcinoma of larynx can be determined by real-time PCR technique. An increase in COX-2 mRNA may be associated with carcinogenesis of carcinoma of larynx, and it may be useful as a biomarker in laryngeal cancer.

OBJECTIVE To study the expressions and significance of Fas/APO-1 protein and caspase-3 in human middle ear cholesteatoma and to investigate the relationship between their expressions and the apoptosis of cholesteatoma. METHODS The specimens from the middle ear cholesteatoma tissue of 20 cases and external ear skin of 10 cases were examined by immunohistochemical SP method and TUNEL method. RESULTS There was a significant difference in the expressions of Fas/APO-1 and caspase-3 positive cells between choleseatoma epithelium and normal external ear canal skin(P

The inhibitory effects of two kinds of selective cyclooxygenase-2 inhibitors on the proliferation of human carcinoma of larynx Hep-2 in vitro and their corresponding mechanisms were investigated. Hep-2 cells were cultured with two kinds of selective cyclooxygenase-2 inhibitors (Sc-58125 and Celecoxib) at various concentrations for 24 h. Morphological changes were observed under the phase microscopy and the growth suppression was detected by using MTT colorimetric assay. Apoptotic DNA fragments were observed by agarose gel electrophoresis, and the cell cycle and apoptotic rate were detected by flow cytometry (FCM) respectively. Hep-2 cells became rounded and detached from the culture dish after being treated with Celecoxib for 24 h, however, they remained morphologically unchanged with Sc-58125. Sc-58125 could increase G2 phase cells, whereas, Celecoxib rose G1 phase cells. Both of the two effects were dose-dependent. Moreover, the Hep-2 cells cultured with 50 micromol/L and 100 micromol/L Celecoxib showed obvious apoptosis, with the nuclear DNA of cells exhibiting characteristic DNA ladder. So Sc-58125 could inhibit the proliferation of Hep-2 cells by altering the G2 phase cells. However, Celecoxib had the same effect by changing the G1 phase cells and inducing apoptosis at higher concentration.
Antineoplastic Agents/pharmacology ; Apoptosis/drug effects ; Cell Proliferation/drug effects ; Cyclooxygenase 2 Inhibitors/*pharmacology ; Dose-Response Relationship, Drug ; Laryngeal Neoplasms/*pathology ; Pyrazoles/*pharmacology ; Sulfonamides/*pharmacology ; Tumor Cells, Cultured