Study on the induced differentiation of bone marrow-derived mesenchymal stem cells into inner ear hair cell-like cells in vitro / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To investigate the feasibility of orientation-induced differentiation of rat bone marrow-derived mesenchymal stem cells (MSC) into cochlear hair cell-like cells in vitro.</p><p><b>METHODS</b>MSC were extracted, cultured and identified. The organ of Corti was isolated from post natal day 1-day 3 Sprague-Dawley rats. Then MSC were co-cultured with organ of Corti for 14 days in vitro. The expression of hair cell markers (myosin VIIa, math1 and calretinin) was detected by immunocytochemical analyses and by reverse transcription-polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>The differentiated cells were immunopositive for myosin VIIa, calretinin and math1. And RT-PCR results indicated that these differentiated cells expressed hair cell markers Math1 and myosin VIIa.</p><p><b>CONCLUSIONS</b>MSC cultured in vitro could be successfully induced to differentiate into hair cell-like cells with hair cell molecular markers.</p>

Diagnostic value of osseous diversity on CT to sinonasal inverted papilloma / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To evaluate the CT characteristics of osseous diversity in patients with sinonasal inverted papilloma (SIP) and to correlate these characteristics with the origins of tumors.</p><p><b>METHODS</b>Sinonasal CT images of 28 patients were reviewed retrospectively to detect areas within which there was focal hyperostosis. The correlation between the sites on the CT scans within which there was osseous diversity and the origin of the tumors in the surgery was analyzed.</p><p><b>RESULTS</b>Surgical evaluation of 22 lesions with focal hyperostosis in CT images revealed that 20 of these lesions coincided with the actual origin of tumor. The focal hyperostosis on CT images corresponded to the actual tumor origin in 71.4% of cases. It denotes the origin of SIP could be predicted from the focal hyperostosis site. The origin of the other 2 cases were disaccord with the focal hyperostosis site, one case had the origin of uncinate process but hyperostosis of anterior middle turbinate, another case had the origin of superior turbinate but hyperostosis of uncinate process. Nine lesions of 28 patients had air sign, 21 lesions had bone absorption and destruction and 19 lesions had bone displacement in CT images. The pressure from tumor growth can induce varied bone destruction and displacement, the source of SIP can be estimated by the bone destruction site and displacement direction.</p><p><b>CONCLUSIONS</b>There has a relatively high concordance between the origin of the SIP and focal hyperostosis on CT, The source of SIP could be discerned indirectly by bone destruction and displacement, these conduce to assess the disease before surgery and make pertinent operation.</p>

Cultivation, identification and ultrastructural observation of the proliferative cells from the newborn rat cochlea / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To explore whether there could be proliferative cells in the cochlea of the newborn rat or not and what kinds of cells should be differentiated from the proliferative cells while to study the effect of the growth factors on the proliferative cells and the ultrastructure of the proliferative cells.</p><p><b>METHODS</b>The Corti's organ were dissected from the cochlea of newborn SD rats and cultured. The proliferative condition of cells was tested by infusing the 5-bromo-2-deoxyuridine (BrdU) into the culture medium. And the variety of the spheres and differentiated cells were identified by immunohistochemistry. Corti's organ from forty-eight surface preparations was randomly divided into 4 groups: control group; epidermal growth factor (EGF) group; basic fibroblast growth factor (bFGF) group and EGF + bFGF group, with each group including 12 Corti's organ, and then the number of cell spheres of each Corti's organ was counted. The data was statistically analysed with ANOVE. Finally, the proliferative cells were observed under scanning electron microscope and transmission electron microscope.</p><p><b>RESULTS</b>(1) The cell spheres can be observed in the cell culture of the Corti's organ. In present experiment, 90.1% of cells in spheres were labeled by BrdU, while nestin of spheres, the marker of hair cells--myosin 7A, espin, and phalloidin of the differentiated cells were positive. The marker of neuron-microfilament-M was also positive, and some differentiated cells were labeled by myosin 7A and BrdU, espin and BrdU, NF-M and BrdU at the same time. (2) The average number (x +/- s) of spheres from single Corti's organ was: 45.3 +/- 23.00 in control group, 86.2 +/- 34.1 in EGF group, 96.5 +/- 33.6 in bFGF group and 131.2 +/- 47.00 in EGF + bFGF group. There were significant differences between other groups respectively (P < 0.05) but there was no significant differences between EGF group and bFGF group (P > 0.05). (3) Scanning electron microscopy and transmission electron microscopy showed that cells of the spheres were round and had the same size and many short and thin microvilli on the surface of these cells. The cytoplasm were rich of organellae such as endoplasmic reticulum, mitochondrion, and cytoskeleton such as microfilament, microtube, et al. Tight junction, desmosomes and gap junctions between two adjacent cells were seen.</p><p><b>CONCLUSIONS</b>The proliferative cells are observed in the cochlea of the newborn rats and proliferative cells could differentiated into hair cells with bundles-like structure and neuron. Both EGF and bFGF possess the promoting effects for proliferation on the proliferative cells while the proliferative cells have characters of earlier immature cells.</p>