[Effect of StarD7 and Wnt/ß-catenin signal pathway on the testosterone secretion stimulated by Annexin 5 in rat Leydig cells].

OBJECTIVE: This research aims to study the internal mechanism that promotes the testosterone synthesis by StarD7 and Wnt/ß-catenin, and explores a new regulatory pathway of testosterone synthesis. METHODS: After treated with 1 nmol/L Annexin 5 for 24 h, the culture media were collected for testosterone measurement by chemiluminescence assay. The expressions of StarD7 and ß-catenin at mRNA and protein levels were detected by RT-PCR and western blot respectively. The cellular location of ß-catenin was identified by immunofluorescence. RESULTS: Comparing with the control groups, under the treatment with Annexin 5, the level of testosterone raised 176%[(7.83±0.32)vs.(21.6±1.1), P<0.05], StarD7 mRNA in the experimental groups increased 55%[(1.12±0.08)vs.(1.74±0.11), P<0.05], and ß-catenin mRNA increased 48%[(1.15±0.08)vs.(1.70±0.05), P<0.05]. At the level of protein, the expression of StarD7 in the experimental groups increased 42%[(1.06±0.09)vs.(1.51±0.07), P<0.05], and ß-catenin increased 55%[(1.02± 0.01)vs.(1.58±0.02), P<0.05]. Immunofluorescence identified that ß-catenin was accumulation in the nuclear of the rat Leydig cells in the experiment groups cultured with Annexin 5. CONCLUSION: StarD7 and ß-catenin have both increased significantly at the mRNA and protein levels under treatment with the Annexin 5, and ß-catenin were accumulation in the nuclear of the rat Leydig cells. It suggests that StarD7 and ß-catenin both regulate the effect of Annexin 5 in testosterone production of rat Leydig cells. This regulation may active the Wnt/ß-catenin signal pathway, then increase the expression of the StarD7, eventually raise the progress of the testosterone secretion in rat Leydig cells.

[Study of three dimensional reconstruction and visualization of human mandible].

PURPOSE: This study is designed to reconstruct 3-D digital visible mandibular model using digital human database. METHODS: An appropriate cadaver was fixed, and fused through arterial infusion, then embedded and sliced. The 2-D imaging data of mandible were obtained from this virtual human, and the virtual mandible was reconstructed using Amira software. RESULTS: Complete and accurate data of the mandible sections were collected, with which the virtual mandible was reconstructed three dimensionally. This virtual mandible displayed accurately the anatomical structure of the actual mandible, including the location and direction of the mandibular teeth and the mandibular canal. CONCLUSION: The 3-D mandible was constructed through the database of the digital human. The visible mandibular model will be an important learning tool in oral and maxillofacial anatomy and surgery, diagnosis and operation of mandibular diseases, and mandibular dental implantation.