Effect on secretory function of rat submandibular glands caused by ischemia reperfusion / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the injury stress responses caused by ischemia reperfusion and its effects on the salivary secretory function of rat submandibular glands.</p><p><b>METHODS</b>An in situ ischemia reperfusion experimental model of rat submandibular glands was developed. The rat submandibular glands were subjected to 90 min of ischemia without denervation followed by reperfusion for 1, 12, 24, and 72 h. Salivary secretion, histological changes, reactive oxygen species (ROS) levels, and cellular apoptosis of the involved submandibular glands were detected after reperfusion.</p><p><b>RESULTS</b>The secretory function of the glands decreased at 1 and 12 h, and the saliva secretion gradually had the same value as that of the control sample 72 h after reperfusion. Increasing inflammatory cells infiltration, cellular atrophy, and tissue edema were observed especially after reperfusion for 12 h. The level of ROS and the number of apoptotic cells exhibited the same tendency, and higher ROS levels and more apoptosis cells 1 and 12 h after reperfusion were observed.</p><p><b>CONCLUSION</b>Our study suggests that ischemia reperfusion can cause a series of injury stress responses in submandibular glands, which might have an important function in the early phase dysfunction of transplanted submandibular glands.</p>

Influence of carbon monoxide on the expression of adhesion molecules stimulated with tumor necrosis factor-alpha and interleukin-1beta on human gingival fibroblasts / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the influence of carbon monoxide on the expression of adhesion molecules stimulated by inflammatory cytokines on human gingival fibroblasts.</p><p><b>METHODS</b>Human gingival fibroblasts were stimulated with 50 ng x mL(-1) tumor necrosis factor (TNF)-alpha and 10 ng x mL(-1) interleukin (IL)-1beta concurrently in the presence or absence of 500 micromol x L(-1) carbon monoxide releasing molecule (CORM). Expression of intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1 at protein and mRNA level was examined by Western blot and reverse transcription polymerase chain reaction (RT-PCR), respectively. Activity of transcription factor NF-kappaB was evaluated by reporter gene assay.</p><p><b>RESULTS</b>Expression of ICAM-1 and VCAM-1 on human gingival fibroblasts increased dramatically after concurrent stimulation of TNF-alpha and IL-1beta, while CORM inhibited the upregulation of ICAM-1 and VCAM-1. CORM decreased the activity of NF-KB stimulated by TNF-alpha and IL-1beta.</p><p><b>CONCLUSION</b>Carbon monoxide could be a promising way in treating of periodontitis.</p>

Establishment of a green fluorescent protein-labeled mouse model of adenoid cystic carcinoma / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To establish a novel nude mice model which can be visualized in real time and detected in a continuous and dynamic way for the development and metastasis of adenoid cystic carcinoma.</p><p><b>METHODS</b>Human adenoid cystic carcinoma cells, ACCM cell line, were infected with retroviral vector of pLEGFP-N1 and then screened for a single colony of ACCM-GFP cells. Cell proliferation and morphological analysis were conducted for ACCM and ACCM-GFP cells. Nude mice lingual carcinoma model was set up with ACCM-GFP cells injection and real time observation with fluorescence imaging on ACCM-GFP tumors was performed subsequently. Histological assay was analyzed for ACCM and ACCM-GFP tumors as well.</p><p><b>RESULTS</b>ACCM-GFP cells were able to express GFP stably in the long term. ACCM and ACCM-GFP cells showed no significant difference in cell proliferation and morphology, and no significant difference of histological characteristics in vivo could be found between ACCM and ACCM-GFP tumors. Tumor development could be monitored in real time with fluorescence imaging system in vivo.</p><p><b>CONCLUSION</b>GFP-expressing ACCM tumor model can be applied to detect and observe its development in the long term in a noninvasive, real time and dynamic way. It is also a kind of ideal in vivo mouse model for adenoid cystic carcinoma research.</p>

Immunogenicity of osteoblasts prior to and after liquid nitrogen cryopreservation / 中国组织工程研究

BACKGROUND: Cryopreservation can decrease tissue and organ immunogenicity. The effects of cryopreservation on cell immunogenicity are disputed.OBJECTIVE: To investigate the effects of liquid nitrogen cryopreservation on osteoblast immunogenicity. DESIGN: Randomized,controlled ,paired-sample experiment. SETTING: This study was performed in the Laboratory Center, Qilu Hospital Affiliated to Shandong University between July 2003 and March 2004. MATERIALS: Four New Zealand rabbits of either gender were included for this study. 3H-TdR was provided by Nuclear Medicine Institute of Shandong University. METHODS: Osteoblasts were cultured from the tibial periosteum of New Zealand rabbits and then cryopreservated in the liquid nitrogen for 3 months and defrosted. Cryopreservated and thawn osteoblasts were set as cryopreserved group and freshly cultured osteoblasts were set as non-cyropreserved group. Major histocompatibility complex (MHC)-I positive rate was examined by flow cytometry assay prior to and after cryopreservation. Simultaneously, mixed lymphocyte-osteoblast cultures were established. Lymphocyte stimulation index was calculated after counting the flares using β liquid scintilloscope. MAIN OUTCOME MEASURES: MHI-I antigen positive rate and lymphocyte stimulation index prior to and after cryopreservation of osteoblasts. RESULTS: MHI-I antigen positive rate and lymphocyte stimulation index of osteoblasts was significantly higher in the non-cryopreserved group than in the cryopreserved group (P＜0.01). CONCLUSION: The immunogenicity of cryopreserved osteoblasts was significantly decreased. Liquid nitrogen cryopreservation is an ideal method to decrease the immunogenicity of osteoblasts.

Construction of Recombinant Adenoviral Vector Carrying the Human BMP-2 Gene with the Technology of in vitro Ligation / 中国肿瘤生物治疗杂志

Objective: To provide an efficeut protocol for constructing recombinant adenovirus, an in vitro ligation was used instead of homologous recombination. Methods: Gene BMP-2 was ligated into pShuttle 2 vector ( pShuttle 2-BMP-2 ) and then fragment containing BMP-2 gene and promoter pcmvie excised by PI-SCe Ⅰ and Ⅰ-Ceu Ⅰ endonuclease. The fragment was further combined with adenovirus vector (Adeno-X-BMP-2) , which was finally linearized with Pac Ⅰ and trans-fered to HEK293 to package adenovirus particles. Results: Both PCR assay and restiction analysis showed that the recombined rectors pShuttle2-BMP-2 and Adeno-X-BMP-2 contains the target BMP-2 gene. THe packaged adenovirus was also i-dentified by PCR assay with specific primers for BMP-2. Conclusions: The BMP-2 incorporated recombinant adenovirus was obtained and this laid a foundation for further study on BMP-2 mediated gene therapy. The in vitro ligation method de-scinbed here for constructing recombined adenovirus was more efficient than traditional homologous recombination.