Objective To establish the mice model of AHL, to investigate the relationship between AHL and the cytoactive factors of the cochlear hair cells in C57BL/6J mice, and to classify the presbycusis models of the C57BL/6J mice. Methods C57BL/6J mice were divided into 6 experimental groups by age (A: 3 months old(m), B: 8 m, C: 9 m, D: 10 m, F: 17 m, G: 18 m) . The auditory functions mice were measured by auditory brainstem response (ABR) with the stimulus click and toneburst at 6 kHz and 8 kHz. 3 months later, Groups C , G, E and H were tested again for ABR. After ABR testing, the cytoactive of the hair cells was detected by succinate dehydrogenase staining and surface preparation technique(two mice from each group except groups C and G). Results The ABR thresholds elevated with age, and the marked change of the cochlea was the degeneration of the cytoactive of the cochlear hair cells, especially those of the outer hair cells. In the beginning, the basement of the basal membrane suffered from the mitochondrion degeneration in the outer hair cells, then it spread to the top region. Subsequently, the inner hair cells were involved. Conclusion C57BL/6J mouse was a typical animal model for the AHL,and the main change of the cochlea was the degeneration of the hair cells, especially the outer hair cells. Thus, C57BL/6J mice can be used as a suitable animal model for the study of presbycusis.

Objective Ryanodine receptor (RyR) is one of the Ca2+ release channels on the intracellular Ca2+ stores. RyR induced-Ca2+ release is activated by the voltage-dependent Ca2+ entry, that is, calcium-induced calcium release (CICR). Intracellular free Ca2+ concentration (ECa2+]i) plays a key role on cochlear function. Our study is to investigate the differential expression of RyR in the developing rat cochlea, and to analyze the relationship between the expression of RyR and auditory functional development. Methods Immature SD rats, which were 1 day (P1), 5 days (P5), 10 days (P10), 14 days (P14), 28 days (P28) after parturition, and adutl rats(5 rats for each age) were included in the study. Frozen cochlea sectioning and immunofluorescence were applied to observe the differential expression of RyR. Results The RyR expression in the Corti's organ increased during the cochlear development. It's not significant that the stain was observed on the hair cells and supporting cells in the Corti's organ of P1 and P5 rats. The appearance of the Corti's organ of P10 rats trended to maturity. In P14 rats the RyR expression on hair cells located in the synaptic area against the afferent or efferent nerve, and the strain on supporting cells was extensive. There was little different between the strain on cochlea of P14 and P28 rats. In postmature rat spiral ganglion neurons (SGN), the RyR expression verged gradually from extensive whole cell soma to the synaptic area near to the plasma membrane. Conclusion The RyR expression peaked the 14th day after parturition, which was close to that in the mature cochlea. The time course of the RyR expression during the cochlear development was coincident with that of the auditory functional development. The RyR expression on both hair cells and SGNs located in the synaptic area near to the plasmolemma, implying that RyR induced-CICR was related to the auditory functions such as neurotransmission. Extensive RyR expression in the soma of SGNs at the early stage possibly involved in apoptosis of SGNs during neuron development.

Objective This paper is to validate a speech intelligibility test in Chinese mandarin for the evaluation of speakers with cleft palate, and to determine the intelligibility deficit patterns based on minimal pairs. Methods Thirty cleft palate patients with dysarthria were included as speakers for the test. Then the speech intelligibility of each speaker was rated and the error proportions of each minimal pair were analyzed by SPSS 16.0. The stepwise multiple regression analysis was employed to determine which minimal pairs were the best predictors of reduced speech intelligibility. Results The intelligibility scores were obtained form the thirty speakers ranged from 37% to 92.4%. The error proportion of the minimal pairs was ranged from 0. 13 to 0. 80. The three most problematic pairs, from the most to least severe were dental versus retroflex pair (0.80), retroflex versus palatal pair(0.68), and aspirated versus un-aspirated affricative pair(0.66). The speech intelligibility from cleft palate patients could be predicted at 71.5% accuracy using two pairs, aspirated versus un-aspirated affricative pair, dentals versus palatal pair. Conclusion The speech intelligibility test for Chinese Mandarin speakers with cleft palate can be used as an effective evaluation method, both qualitatively and quantificationally.

Objective To explore the use of auditory steady-state response (ASSR) for threshold evaluation in neonates. Methods 30 neonates 60 ears) were included in the study who passed distortion product otoacoustic emission (DPOAE) screening and 45 neonates (78 ears) who failed DPOAE. The ASSR thresholds were evaluated screening, the significant difference was found between the ASSR thresholds at 250 Hz and the ABR thresholds (P ＜0.05), however the ASSR thresholds at 4 000 Hz and average thresholds were not different from the ABR thresholds (P＞0.05). For the neonates whose DPOAE screening results were abnormal, the ASSR thresholds from 250 to 4 000 Hz and average thresholds were not significant different from the ABR thresholds respectively (P＞0.05). olds were not correlated, but there were significant correlations at 2 000 and 4 000 Hz. For the neonates whose DPOAE screening results were abnormal, the ASSR thresholds and the ABR thresholds were significantly correlated at all the carrier frequencies. Conclusion Reliable and frequency specific results could be obtained by ASSR,so it could be a promising audiometry to evaluate the hearing of neonates.

Objective To study the characteristic of acoustically short latency negative response (ASNR) in auditory brainstem response (ABR) evoked by tone burst in children with hearing loss. Methods ABRs to click and tone burst were recorded from 0～6 years old children with hearing loss using SmartEP auditory evoked potential system. The threshold and latency was analyzed if ASNR was recorded. Results Among all the 80 ears tested, ASNR were recorded in 7 ears (8.75%) when using click, and in 40 ears (50%) when using tone burst. ASNR was most frequently evoked by 1 kHz tone burst (in 37 ears), and 2 kHz (in 25 ears) was the second. Among the ears with ASNR, the lowest threshold of ABR wave V was 65 dB nHL. The lowest threshold of ASNR was 80dB nHL. The latencies of ASNR for 0.5,1,2 and 4 kHz tone burst was 6～8, 5～7,3～5 and 3～4 ms, respectively. The latency decreased along with the increase of intensity. Conclusion ASNR can be recorded while recording tone-burst ABR, but it has no effect in predicting hearing level using the wave V threshold of tone-burst ABR.

Objective To undertake a survey on the prevalence, pathogenic factors and treatment needs of hearing impairment in children under 14 years old in Guizhou province. Methods Using the probability proportion to size (PPS) method, 2 068 children aged 0～14 years were included in the study and in 30 clusters in Guizhou province based on the WHO protocol. Results For children aged 0～14 years, the prevalence of hearing impairment was 3.48% and the prevalence of hearing disability was 1.84 %. There were statistically differences of the prevalence of hearing disability between children aged 7～ 14 years (2.66 %) and 0～ 6 years (0. 51%), and the differences also in hearing impairment between male children (4.22%) and female children (2.54%). The main causes of hearing impairment were ear diseases (50.00%), non-infective conditions (11.11%), genetic conditions (20.83 %) and unknown causes (27. 77%). 3. 58% of all subjects needed medical or surgical treatment and 2. 32% needed hearing aids. Conolusion The prevalence of hearing disability of children under 14 years old in Guizhou province was higher than that of other cities. The main cause of the hearing impairment of children was otitis media with hereditary deafness also ranked in top.

Objective Base on the neighborhood activation model(NAM), to develop the Mandarin monosyllable lexical neighborhood test(M-LNT-monosyllable), which is expected to be useful for evaluating speech perception performance in children with hearing loss. Methods Test items were based on the lexical characteristics of word frequency and neighborhood density which addressed in the neighborhood activation model (NAM). M-LNT -monosyllable consisted of two parts: Lexically "easy" words with high word frequency, which were low phonemically similar to the target word and lexically "hard" words with low word frequency, which were high phonemically similar to the target word. 34 children of 3～5 year old with normal hearing were choosed as subjects to verify easy word and hard word lists. Results 1 979 words for children contained 487 easy words and 419 hard words. Three easy word lists and three hard word lists were developed to estimate the performance of word recognition among normal- hearing children. There were no differences among scores of three easy words lists(P＞0.05), and no difference among scores of three hard words lists(P＞0.05). But there were significant differences between scores of easy and hard words lists(P＜0.01). Conclusion The development of the lexicon was affected by the lexical characteristics. Normal-hearing children with some lexical techniques were affected by the lexical characteristics when they recognized the spoken words, but children with less lexical technique didn't show the same result because the recognition was processed on the phonetic level.

Objective To summarize the clinical diagnosis and treatments of 55 reflux laryngitis (RL) pa-tients, and to study the relationship between gastroesophageal reflux disease (GERD) and RL. Methods The pa-tients went through the following diagnostic process consisting of the collection of medical history, laryngoscopy, gastroscope, X-ray barium meal examination, vocal evaluation, therapy of anti-acid and anti-reflux. Results The laryngeal manifestations of RL mainly consisted of laryngeal discomfort or foreign body sensation (89. 1%), chronic cough (36.4 % ), hoarseness (20 % ), laryngeal pain (18. 2 %), even severe aspiration or laryngismus (10.9%) and so on. With the laryngoscopy we could see congestion in arytenoids area (67.3%), swelling or pachynsis of a mucosal fold in interarytenoid area (43.6%), edema of true or false vocal cord(40%), a little dropsy staying in piriform sinus (32.70% ), contact ulcer or granuloma on posterior extremity of a vocal cord (20 % ), artificial sulcus under vocal cords (16.4 %). RL patients might have mild voice disorder, among whom 65.5 percent displayed ten-sion dysphonia. Fundamental frequency (F0), jitter, shimmer and normalized noise energy (NNE) of RL patients increased. Compared with the controls, there were significant differences (P<0. 05) except for the F0 of female pa-tients. The manifestation and physical symptoms were improved or disappeared after the treatment with proton pump inhibitor (PPI). Conclusion RL is one of the important manifestations of GERD out of digestive tract. Typi-cal RL manifestation is mainly a pathological process in the postero-glottis. Clinically, PPI can be used as not only a treatment but also a tentative diagnosis of RL.

Objective To investigate plasma pharmacokinetics profiles of compound betameth in guinea pig after postaurieal and systemic administrations,and to explore the possible pathway for postaurical injection. Methods 1 ml compound-betameth was injected postaurieally and intramuscularly into the guinea pig. Blood were samples obtained 0. 5,1,1.5,2,3,5,7 h and 1,2,4 w after the administration of contralateral sigmoid sinus blood and circulatory blood respectively. High performance liquid chromatography was used to dectet compound betameth in the samlowing postaurieal administration. The Cmax(peak concentration) in sigmoid sinus of postaurieal group was 2.56 and 3.03 higher than those in the contralateral and the systemic group. The AUC((area under the ct curve) was 2.41 postaurieal administration. The Cmax and AUC in postaurieal group were 0. 13 and 0. 32 higher than systemic group. Conclusion The postaurieal injection reached a higher concentration of drugs in the sigmoid sinus blood, and remained a lower concentration in circulatory blood.

Objective The light and electron-microscopic examination was utilized to study the tissue from middle ears diagnosed as having tympanosclerosis. The main purpose of this article is to understand the clinicopathologic and electron-microscopic characteristics of 68 patients with tympanosclerosis. Methods The material for histopathologic and electron-microscopic studies were taken from the tympanic mucosa in various localities, especially from the whitish sclerotic masses in the tympanum of the patients with tympanosclerosis, during middle ear surgeries between 2006 and 2008. Specimens were divided into two groups: one group of 68 specimens was fixed and stained for light microscopic study with hematoxylin-eosin; the second group of 12 specimens was viewed in the electron microscope. Results The specimens from tympanic mucosa showed granulation tissue with infiltration of chronic inflammatory cells, and slight fibrosis in the submucosal layer. The histopathology of the plaques after haemaoxylin and eosin staining revealed dense bundles of collagen with hyaline degeneration and scattered areas of calcification. An ultrastructural examination of these specimens revealed fibrocytes that were irregularly shaped, elongated, and degenerating. The osmiophilic cytoplasm contained vesicles and collagen bundles. There were clusters of mitochondria in perinuclear cytoplasm and lots of electron dense calcareous deposits within lysosomes and degenerated mitochondria in fibrocyte cells. Conclusion The histopathologic examinations of tympanosclerosis revealed dense fibrous and collagenous connective tissues, poor in cell, with hyaline degeneration and occasional calcification in the tympanic mucosa. Electron-microscopic studies further revealed marked proliferation of collagen fibers and electron dense calcareous deposits within lysosomes and degenerated mitochondria in fibrocyte cells.