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To explore the feasibility of interleukin 1 receptor associated kinase-4 (IRAK-4) as gene therapy target for liver ischemia/reperfusion injury (I/RI) and effective approach in vivo for short hairpin RNA (shRNA) interference used to gene therapy in liver graft hqappened.Sprague-Dawley rats were randomly divided into three groups: the control group, the in vivo transfection group (IVT) and the cold ischemia transfection group (CIT). Experiments of orthotopic liver transplantation were performed by two-cuff method. CIT were perfused with IRAK-4-shRNA plasmid (pSIIRAK-4) during cold ischemia phase, IVT received the equivalent volumes (2 mL) of pSIIRAK-4 after portal vein inosculated, and the control group leaved without any treatment. At 0 min, 60 min and 180 min after reperfusion, the expression of IRAK-4 gene and protein level were determined by RT-PCR and Western blot. The serum TNF-alpha level was detected by ELISA. Liver histopathological changes and cell apoptosis were observed by electron microscope and TUNEL.After reperfusion, the expression of IRAK-4 were largely depressed in CIT than that of IVT and the control group (P0.01), and furthermore, the serum TNF-alpha level, proportion of hepatocyte apoptosis and severity of hepatocyte injury were also lower than the latter.These results indicate that depression IRAK-4 expression with IRAK-4-shRNA through portal vein perfusion during cold ischemia phase could effectively blunt graft hepatic I/RI.

This experiment was designed to develop an experimental model of mandibular distraction osteogenesis in goats for determining the principle and the process of distraction osteogenesis.Eight 3-month-old, healthy domestic goats were randomly divided into four groups (n = 2 per group). The animals from each group were killed at 1, 2, 4, and 6 weeks after bone distraction, respectively. The sections of newly formed bone were obtained and evaluated with histologic and radiographic study. We also assessed the newly formed bone with bone density examination.The specimens of right mandible increased averagely 10 mm after distraction. The Newly formed bone was demonstrated histologically. The X-ray examination and bone density measurements showed that the bone density increased with the time of fixation.Goat is a proper experimental animal for modeling mandibular distraction osteogenesis, and in this regal, it is important to keep the direction of distracter force in conformity with the direction of the expected distraction osteogenesis for avoiding the side force and thus ensuring successful distraction and good quality of newly formed bone.

To make sure whether super-high molecular weight polylactate is toxic to the body after it has been implanted into the body for a long period.We implanted super-high molecular weight polylactate into the rats and took the specimens of blood at 3, 6, 9, 12 months after the operation. The changes of proteins, electrolyte, enzyme and other indices were observed. At the same time, the tissue around the implants were taken out to carry out the histological observation.At 3, 6, 9, 12 months after the operation, the levels of albumin, globulin, total bilirubin, direct bilirubin, triglyceride, glucose, K+, Na+, Cl-, Ca2+, alkaline phosphatase, glutamic-pyruvic transaminase in the blood plasma were all in the normal range; there were no significant differences between the experimental group and the control group. The level of lactate dehydrogenase increased slightly, but there was no statistically significant difference between the experimental group and the control group. There were no non-reversible immune rejection around the implants in the histological observation.Super-high molecular weight polylactate is not toxic to the body after it has been implanted into the animals for a long period.

To study the stress distribution of intact mandible, especially that of the mandibular angle under different muscle loading and biting condition.Develop a more accurate, more objective mandibular model, measure the different stress patterns on the outer surface of the mandible by strain gauges due to different biting sites (INC and ICP) and different loading methods (masseter, temporalis and four pairs of muscles).It was found that the strain in the zone of mandibular angle is more markedly under masseter loading; that the strain in the zone of anterior mandibular ramus is more markedly under temporalis loading; and that the stress in the zone of mentum becomes a tension because of the medial pterygoid under the load of four pairs of muscles. During anterior teeth biting, the stress of mandible angle is larger than that of the bilateral molar biting. When an occlusal load is on the ipsilateral molars, there is a reversal result of the stress direction in the upper line of the mandibular angle.Different muscular loading and biting condition can change the stress distribution of the mandible. It is important to develop a functional model of human mandible to study its complex biomechanics behavior.

To study the differential expression of transforming growth factor beta 1 (TGF beta 1) in oral carcinoma and stroma lymphocytes by induction chemotherapy and inquire into the mechanism of TGF beta 1 information transmission.Forty cases of oral tumor were treated with MTX, CDDP and PYM via subcutaneous implantable drug pump, in situ hybridization method was adopted to detect the expression of TGF beta 1 mRNA.The positive expression of TGF beta 1 mRNA was enhanced in oral carcinoma (P0.05). After the induction chemotherapy via subcutaneous implantable drug pump, not only the expression level of TGF beta 1 in malignant cells of invading front zone was up-regulated (P0.05), but the expression level of stroma lymphocytes was higher than before.These data demonstrated that TGF beta 1 not only has transforming potential, but also enhances the malignant progression of oral carcinoma. It was clear that TGF beta 1 can act as a tumor suppressor and a significant stimulator of T-cell-mediated tumor cytotoxity as well.