Expression of programmed cell death 5 and apoptosis during atrophy of the parotid gland cells / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the expression and relationship of programmed cell death 5 (PDCD5) and cell apoptosis in the parotid gland after leading duct ligation in rat and elucidate the role of PDCD5 on the atophy of parotid gland.</p><p><b>METHODS</b>The Wistar rat model of leading duct ligation was established, and the samples of parotid gland were obtained from different time point (0, 1, 3, 5, 7, 14, 21, 30, 60, 90 and 120 d). The expression of PDCD5 protein was examined by immunohistochemistry. Cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL).</p><p><b>RESULTS</b>The distribution of PDCD5 protein in normal parotid was in cytoplasm with uniformity. The expression of PDCD5 protein was significantly increased and reached the peak at 3 d (1.261 ± 0.048) following main duct ligation. PDCD5 was located both in cytoplasm and nuclear of parotid gland cells. The PDCD5 density in acinar cells was higher than that in duct cells at day 1 and 3 after duct ligation (P < 0.01). The apoptotic cells were obviously upregulated at 3 d after duct ligation. The apoptosis index observed in acinar cells [(21.750 ± 0.119)%] was more than that in duct cells [(5.720 ± 0.205)%]. The difference of apoptosis index between acinar cells and duct cells was statistically significant (P < 0.01). The increased PDCD5 levels were positively correlated with cell apoptosis induced by duct ligation.</p><p><b>CONCLUSIONS</b>The expression of PDCD5 is associated with the atophy of the parotid gland after rat parotid duct ligation, indicating that PDCD5 might play an important role in apoptotic pathways after parotid duct ligation.</p>

Use of allogenic acellular dermal matrix combined with autologous epidermal cells for the repair of tissue defect / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate a method for the repair of tissue defect.</p><p><b>METHODS</b>Allogenic acellular dermal matrixes (ADM) were implanted to full-thickness skin defects made on the dorsa of rats. Two weeks later, autologous suspended epidermal cells were transplanted on to the surface of vascularized ADM. Respectively, neoepidermis was macroscopically observed 2, 3, 5 weeks after grafting, and samples were taken to make routine paraffin sections for microscopical examination, and immunohistochemical staining for type IV collagen was also performed.</p><p><b>RESULTS</b>The vascularized ADM could support proliferation and differentiation of epidermal cells, and also could promote the formation of dermal-epidermal junction. Suspended epidermal cells in an artificial culture system in vivo could develop into mature epidermis. The reconstructed skin not only looked like the normal one in appearance in which hair was removed, but also revealed a better function.</p><p><b>CONCLUSIONS</b>Full-thickness skin defect can be repaired by transplanting autologous epidermal cell suspension on to vascularized ADM.</p>