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To detect the expression of Math1, Hes1 and Hes5 in greater epithelial ridge (GER) cells of rat cochlear and explore their influence on hair cell differentiation.Postnatal day 0 (P0), day 1 (P1) , day 3 (P3) day 4 (P4) and day 5 (P5) rat cochlear were dissected respectively and then pure GER cells were separated by a combinatorial approach of attachment and mechanical separation. The total RNA of GER cells was extracted by Trizol one step method and the expression of Math1, Hes1 and Hes5 in GER cells was detected with reverse transcription polymerase chain reaction.Math1 was expressed in P0 - P5 rat GER cells and Hes1 was expressed only in PO - P3 rat GER cells, while there was no expression of Hes5 in P0 - P5 rat GER cells.Probably only when the expression of Math1 reaches a certain level can it induce GER cells to differentiate into hair cells. Meanwhile this process might controlled by Hes1 to some extent.

In studying genetic factors in hearing loss among Chinese hearing-impaired population, a Chinese family with deaf-mute that had been reversion inherited through five generations was found (named pedigree L021). X linked recessive inheritance was hypothesized to be the transmission in this family. A total of 64 members in this family were investigated. Of these, audiometric evaluation was performed on 31 members, including 8 males with deaf-mute. Most affected individuals showed deafness or profound sensorineural hearing loss. Blood samples were obtained from 31 consented individuals in this family. Pedigree analysis indicates a X-linked recessive inheritance pattern in pedigree L021. The pedigree described herein provides an excellent model for further study on the molecular mechanism of congenital deaf-mute.

To investigate if auditory neuropathy have inferior vestibular nerve (IVN) lesion and to explore the relation between AN and the IVN lesion by vestibular evoked myogenic potentials (VEMPs).VEMPs were observed in 13 patients with auditory neuropathy. And the relation among the duration, hearing threshold of lower frequency and speech discrimination score with VEMPs were observed.Fifty-four percent patients in auditory neuropathy had abnormal VEMPs. They took the form of lower amplitude and no response. The statistical analysis showed that the abnormality of VEMPs had no correlation with lower frequency hearing loss, the duration and speech discrimination score.The IVN dysfunction may coexist with auditory neuropathy, having lesion in the IVN. However, there was no significant relation between the severity of AN and VEMPs, which meant that AN and inferior vestibular neuropathy had their independence to some extent.

Vestibular evoked myogenic potential (VEMP) has been utilized in clinic to test the function of saccule. In the present study, 3 stimulus modes were applied to 21 normal adults and intended to draw in a clinical test protocol.The normal latency and amplitude of VEMPs of 21 normal subjects were recorded and the ratio of bilateral amplitudes and asymmetry were calculated.The response to binaural clicks were similar to the response of the monaural clicks. The interindividual variation in amplitude were large, but the latency varied little.VEMPs is a stable myogenic potentials. Monaural and binaural clicks stimulus can be used in clinical practice. The latter is appropriate for normal hearing subjects. Amplitude measurement is probable to evaluate the asymmetry of bilateral saccular function and may reveal saccule lesion.

Numerous studies have shown that the health of spiral ganglion neurons is highly important for hearing. As a trophic factor of spiral ganglion neurons, neurotrophin 3 (NT3) is a potential candidate for prevention of spiral ganglion neuron degeneration in human. In our experiments, efficient transduction and long term expression of foreign gene of cochlea cells has been found with adenovirus carried lacZ gene (Ad-lacZ). A model of guinea pig deafness was made by intense noise exposure, which destroyed the entire organ of Corti in the middle part of the cochlea. Seven days after noise exposure, the animals were anesthetized and 1 10(8) recombinant adenoviral particles were injected into the scala tympani through the round window membrane. Animals inoculated with neurotrophin 3 adenovirus(Ad-NT3) were designated as the experimental group, animals inoculated with Ad-lacZ vector served as the control group. Four weeks after the inoculation of the virus, NT3 immunoreactivity was observed in the Ad-NT3 inoculated group. HE histochemical staining results showed that in the Ad-lacZ injected group, the neuronal degeneration was severer and the density of spiral ganglion neurons was significantly lower than those in the Ad-NT3 injected group. Our results demonstrate that with adenovirus-mediated overexpression NT3 may be developed into a new treatment to prevent secondary spiral ganglion degeneration following the damage to Corti organ.

Background Controversy still exists in the indication and timing of surgical treatment of pulmonary hamartoma (PH). The objective of this study is to summarize the experience and the outcome of the surgical treatment for pulmonary hamartomas, and to assess the effectiveness and necessity of surgical therapy administered in patients with pulmonary hamatoma as well as clinical and pathological features and long-term follow-up results. Methods This retrospective report has reviewed a 20-years clinical history of surgical treatment for 39 patients with PH from 1985 to 2006. These thirty-nine patients underwent 40 operations as follows: wedge resection (23), enucleation (10), segmentectomy (3), lobectomy (3), and pneumonectomy (1). Results The PH occurred most frequently (78.1%) in the patients aged 40 to 60 years and the sex ratio (male/female) was 2.25/1 in our series. No postoperative death was encountered. One patient with pleural effusion was cured after thoracentesis. All of these 39 patients were proved with pathologic diagnosis of PH and the popcorn calcification was found in 6 cases before operation. In 38 cases having the mean follow-up of 7.3 years, a patient was operated thrice for regional recurrence. Conclusion Fast frozen section in operation is critical for acquire accurate pathological diagnosis. Due to potential trend of recurrence or malignance, patients with hamartoma should be submitted to a complete evaluation and a regular follow-up.