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Ming-min Dong

Publications and source records attributed to Ming-min Dong.

5 recordsLinked to original sources
PubMed2006

[Observation of auditory brainstem response and distortion product otoacoustic emission on the animal model of autoimmune auditory neuropathy].

OBJECTIVE: To set up an animal model of autoimmune auditory neuropathy and to observe the auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) in guinea pigs. METHODS: The spiral ganglion and the cochlear nerve were obtained and purified by electrophoresis from 250 normal guinea pigs. The purified cochlear nerve antigen was mixed with an equal volume of complete Freunds adjuvant for immunization. Seventy guinea pigs were divided into three groups: experiment group (50 guinea pigs), control group (10 guinea pigs), normal group (10 guinea pigs). ABR, DPOAE, serum IgG levels, and morphological changes of spiral ganglion cells and the cochlear nucleus were observed. The protein expressions of the antigen were examined by immunohistochemistry and the super-structure of the auditory nerve were observed. RESULTS: The threshold of ABR response increased ranged from 10 to 25 dB in 32% (32/100 ears) of the guinea pigs. The peak latencies of waves I , III and the interpeak latency I approximately III were prolonged in the hearing loss group of guinea pigs. Prolonged peak latency of wave III was noted in hearing loss group at 2 and 3 weeks post immunization and slowly decreased to normal peak latency. The amplitude of DPOAE was no difference in the guinea pigs. The levels of serum IgG increased significantly compared with those of the control group. Inflammatory cell infiltration was observed in the cochlear nerve and the number of spiral ganglion cells detected. On the contrary, inflammatory cell infiltration was not observed in the cochlear nucleus. The cell densities and the across-sectional areas of neurons in anteroventral cochlear nucleus and posteroventral cochlear nucleus were no difference in the guinea pigs. The antigen protein distributed strictly in cochlear nerve and the spiral ganglion. Some demyelinated areas in cochlear nerve was observed in this group. The threshold of ABR response in 68% guinea pigs (68/100 ears) did not increase. The data of DPOAE and the serum IgG levels show no difference compared with the control group. There were not pathological observation in spiral ganglion cells, cochlear nucleus and cochlear nerve. CONCLUSION: An animal model of autoimmune auditory neuropathy has been set up successfully and the character of the ABR and DPOAE was observed.

Animals↗
PubMed2005

[Structure and function influence of cochlear after dexamethasone intratympanic application].

OBJECTIVE: To study the changes of the structure and function of cochlear after dexamethasone intratympanic application. METHODS: Forty-five guinea pigs were divided into three groups as normal group, 0.9% sodium chloride injection group and 0.5% dexamethasone group. By using the auditory brainstem response (ABR), the superoxide dismutase (SOD) activity, the nitric oxide (NO) value and cochlear surface preparation technique, the changes of structure and function of cochlear after intratympanic Dexamethasone application has been investigated in this study. RESULTS: There was not significant difference among three groups in ABR thresholds of wave III (F = 0.5, P = 0.5). There was not significant difference among three groups in SOD activity (F = 2.45, P = 0.96). There was not significant difference among three groups in NO value (F = 3.1, P = 0.3). There was not significant difference among three groups in necrotic values of hair cells on the cochlear surface specimens in 15 mm from basal turn (F = 0.93, P = 0.45). CONCLUSION: There is no change of cochlear construction and function after intratympanic Dexamethasone application.

Administration, Topical↗
PubMed2003

[Construction of bicistronic eukaryotic vector containing basic fibroblast growth factor and study of their functions in gene therapy for hearing impairment].

OBJECTIVE: To construct basic fibroblast growth factor(bFGR) and enhance green fluorescence protein(EGFP) fusion gene eukaryotic expression vector internal ribosome entry site (pIRES)-bFGF-GFP and to evaluate the effect of transduction bFGF gene on noise induced hearing-loss in inner ear hair cells of guinea pigs. METHODS: Human bFGF cDNA was inserted into mammalian expressed plasmid pIRES-EGFP. The recombinant expression plasmid pIRES-bFGF-EGFP was transfected into inner ear of guinea pigs, using lipofectin method. The transduced bFGF gene was mediated by SA lipidsome. IRES- bFGF-GFP was administered into the round window as rescue agent at the same time of noise exposure or as a protective agent 7 days before. RESULTS: SA liposome-mediated bFGF expressed at a high level in the cochlea of guinea pigs, and in the rescue group, a significant lower hearing thresholds was displayed. pIRES- bFGF-EGFP could protect hair cells. It demonstrated that pIRES- bFGF-GFP could protect the inner ear both structurally and functionally. bFGF/EGFP gene could be transcripted and translated into inner ear hair cells of guinea pig. bFGF/EGFP gene could express a specific protein. The recombinant bFGF/EGFP had significant protective effect as well as manifestation of autonomous fluorescence. CONCLUSION: bFGF/EGFP fusion protein not only expressed in hair cells of guinea pig but also showed significant bFGF activity and autonomous fluorescence. IRES induced exogenous gene could enter the hair cells.

Animals↗
PubMed2002

[Improved three-dimension reconstruction of serial frozen tissue sections of the temporal bone of guinea pigs].

OBJECTIVE: To improve the serial frozen tissue sections of the temporal bone of guinea pigs for better three-dimension reconstruction of the computer images. METHODS: The temporal bone of the guinea pigs was first decalcified by formate before embedding with lines marking the position of the specimen in glutin at low temperature. RESULT AND CONCLUSION: Thinner slices, shorter period and more accurate orientation were achieved to highlight the spatial features of the temporal bone, thus facilitating the anatomical study of the temporal bone.

Animals↗