Guo Weiwei

Isolation and Induction of Differentiation of Seine Adipose-Derived Mesenchymal Stem Cells

Abstract Objectives To establish a method for high yield mesenchymal stem cells collection, as well as a culture method for identifying mesenchymal stem cells from the swine adipose-derived mesenchymal stem cell (ADMSC). Methods Swine ADMSCs were isolated from fat tissue with collagenase, followed by induction of differentiation to osteogenic, adipogenic and chondrogrnic cells. The survival curve of the ADMSC at the 37°C and 38°C were measured using WST-1Cell Proliferation Assay Reagent. Result ADMSCs isolated with collagenase from swine neck fat tissue generated a stable uniform appearance after the second generation. The passage period was five days. ADMSC could differentiate into osteogenic, adipogenic or chondrogrnic cells under different culture conditions. The highest growth rate was achieved at 38°C in this study. Conclusion Swine ADMSCs have the potential to differentiate into osteogenic, adipogenic or chondrogrnic cells, and they may be appropriate for transplantation for both research and clinical purpose.

MICRODISSECTION OF MINIATURE PIG EAR

Abstract Objective To investigate the suitability of miniature pigs as an animal model for otological research. Methods Microdissection of the temporal bone was performed on 10 miniature pigs and recorded on photographs. Results The morphology and measurement of the external, middle and inner ear and the lateral recess of the miniature pigs were obtained by microdissection. Conclusion Compared to traditional animal models, the miniature pig may be a better model for biomedical research because of its many similarities in physiological functions with humans. Similarities of the temporal bone structures, including the external, middle and inner ear and the lateral recess, between the miniature pig and human make the animal a potentially useful model for otological research.

A Method for Establishing an Animal Model of Like-Auditary Neuropathy

Abstract Objective: To establish an animal model of like-auditory neuropathy in neonatal rat. Methods The animals were injected with phenylhydrazine hydrochloride or saline at 7-day of age. ABR and DPOAE were performed to assess the auditory function. The cochlea basilar membrane stretched preparation and cochlear frozen sections were prepared for immunohistochemical staining to examine the morphological change of hair cells and spiral ganglion cells (SGNs). Results At 7-day age the ABR waveI, III, V, latencies andI- III,I-V IWIs in the experimental group were significantly prolonged compared with those in the control group. The ABR thresholds were also elevated in the experimental group. We found there is no significant difference in DPOAE in phenylhydrazine hydrochloride exposure group compare to control group. The cochlear hair cells showed no signs of loss in both group, but the total number of neurofilaments positive cells in SGNs were significantly reduced in the phenylhydrazine treated animals. Conclusion Our study suggests that phenylhydrazine hydrochloride can change the auditory function and induce peripheral nerve pathology by targeted mainly the SGNs in neonatal rat.

Effects of combined administration of furosemide and kanamycin on rat auditory nerve

Abstract Objective To determine the effects of combined administration of furosemide and kanamycin on inner ear structures and the auditory nerve in rats. Methods The rats in the treatment group received intravenous injections of combined furosemide and kanamycin sulfate, and the rats in the normal control group received no treatment. The auditory brainstem response (ABR) test was carried out 7 days after drug administration to determine the effects of drug administration on hearing. Cochlear slice and cochlear wholemount were prepared after 7 days of drug treatment. Results After 7 days of drug administration, ABR thresholds were significantly higher in the treatment group than in the control group and neurofilaments were significantly reduced, although the number of spiral ganglia showed no decrease and there were no signs of supporting cell injury. Conclusions Combined administration of furosemide and kanamycin sulfate has an apparent synergistic ototoxic effect. Although spiral ganglion damage may not be apparent within a short time period of drug administration, damage to auditory nerve fibers is obvious.