Biomedical subjects

Chao-Gang Wei

Publications and source records attributed to Chao-Gang Wei.

3 recordsLinked to original sources

PubMed2005

[Voice analysis in pre-lingual cochlear implant adults].

OBJECTIVE: To observe voice characteristic of pre-lingual cochlear implant adults for cochlear implantation and phoniatrics. METHODS: 3s-sustained voice of vowel [ a: ] of 28 pre-lingual cochlear implant adults, 18 pre-lingual deafness adults and 10 adults with normal hearing were analyzed. Specifically, the Voice analyses include fundamental frequency, first formant, second formant, frequency perturbation quotient (FPQ), amplitude perturbation quotient (APQ) and harmonic noise ratio (HNR). The outcomes of 3 groups were compared. RESULTS: The fundamental frequency was lower in cochlear implant group [(175.42+/-25. 31) Hz] than that in deafness group [(210.84+/-54.300) Hz] (P = 0.02). The position of formant of cochlear implant group [F2 = (1264. 64 +/- 152.19) Hz] was more access to normal than that of normal hearing group[ F2 = (1422.44 +/- 232. 37) Hz, P = 0. 02]. FPQ of cochlear implant group (2.09 +/- 1.15) was more access to normal than that of deafness group (5.32+/-4.29, P=0.006). The voice of cochlear implanted and deafness adults were much more different individually. CONCLUSIONS: In the aspect of acoustic characteristic of voice, pre-lingual cochlear implant adults could benefit cochlear implantation finitely. As speech perception of pre-lingual cochlear implant adults was far worse than that of children and post-lingual cochlear implant adults, the general outcome of pre-lingual cochlear implant adults was very limited. Cochlear implant of those candidate should be cautious.

Adolescent↗

PubMed2004

Mandarin tone recognition in cochlear-implant subjects.

This study examined tone recognition in five cochlear-implant subjects who were native speakers of Mandarin and used a Nucleus-22 device. Psychophysical experiments were conduced to measure rate discrimination in individual electrodes from the most apical to the most basal electrodes. The rate range was from 100 to 200 Hz, which corresponded to the range of variation in fundamental frequency for the tonal tokens used in this study. Speech recognition experiments were also conducted to measure tone recognition as function of the number of electrodes from a 1-electrode map to a 20-electrode map. Large individual variability was observed for both rate discrimination and tone recognition result: Average rate discrimination ranged between 0.2 and 1.2 (Weber's fraction) whereas tone recognition ranged between 30% and 70% correct. A highly significant correlation was found between rate discrimination and tone recognition with the 20-electrode map, but a non-significant correlation was observed with the 1-electrode map due to a floor effect in tone recognition. The present result supports the hypothesis that both spectral and temporal cues contribute to tone recognition. In addition, the present result shows that current cochlear-implant subjects produced significantly lower performance than acoustic simulations in normal-hearing subjects, suggesting that neither temporal nor spectral cues have been adequately and appropriately extracted and encoded in current cochlear implants. New designs are discussed to improve tone recognition in cochlear implant subjects.

Adult↗

PubMed2003

[The transduction of neurotrophin-3/GDNF attenuates the SGNC damage in deaf mice].

OBJECTIVE: To investigate the attenuation of cisplatin-induced toxicity in the spiral ganglion neuron (SGNC) by the localized expression of the neurotrophin-3 (NT-3) and glial cell line-derived nerutrophic factor (GDNF) via HSV-Amplicon. METHODS: We constructed the HSV-Amplicon vectors, which could express the NT-3 and GDNF under separate transcriptional control. Helper virus-free amplicon stocks were assessed in vitro for their capacity in the cultured inner ear cells. The ELISA was used to detect the production of NT-3 and GDNF. Three groups of mice were injected with cisplatin (8 mg/kg), followed by instillation of HSVnt-3myc/gdnf, HSVnt-3myc/lac or HSVlac. The numbers of SGNC were analyzed 4 weeks later. RESULTS: The HSVnt-3myc/gdnf transduction resulted in production of NT-3 up to 11.44 micro g/ml and GDNF up to 1.79 ng/ml in cultured medium over 48 h. There were significant differences among three groups (P < 0.01). Cochleae transduced with HSVnt-3myc/gdnf and HSVnt-3myc/lac harbored from the mice had greater number of surviving SGNC. The ratio of SGNC survival (%) in HSVnt-3myc/gdnf, HSVnt-3myc/lac and HSVlac was 88%, 77% and 22%, respectively. CONCLUSION: The transduction of NT-3/GDNF by HSV-Amplicon greatly attenuated SGNC the cisplatin-induced ototoxicity in mice.

Animals↗