BACKGROUND: The osteoblastogenetic function of stem cell and local vasoformation is an important influencing factor in bone tissue engineering restoration.OBJECTIVE: To investigate the function of osteoblast induced, cultured and differentiated from mesenchymal stem cells(MSCs) and the expression of vascular endothelial growth factors(VEGF) in rabbits in itro.DESIGN: A single sample study and repetitive observational measurement by using cells as subjects SETTING: Department of histology and embryology in a university MATERIALS: The study was conducted in the Department of Histology and Embryology of Guangdong Medical College between March and December of 2002. The subjects were rabbits' MSCs.METHODS: The MSCs of newborn rabbits ere isolated and cultured. The cultured cells were induced to osteoblastogenesis with an osteo-inductive medium containing dexamethasone, ascorbic acid and β-glycerophosphate to observe the coloration of alkaline phosphates(ALP) and the formation of mineralized nodule in the cultured cells.MAIN OUTCOME MEASURES: ① observation of cell morphology, ②identification of steoblastogenesis from the cultured cells ③ expression of VEGF in osteoblasts derived from the cultured cells RESULTS: fter MSCs osteo-inductive culture, cells had strong ALP staining with the formation of mineralized node, and the VEGF expression enhanced with the grey scale of 132.3 ± 4.6, which was significantly different from that of the VEGF expression in MSCs( 148.5 ± 5.3) ( P ＜ 0.05).CONCLUSION: MSCs can be induced into osteoblasts with enhanced expression of VEGF, which might participate in the formation of endothelial cells.

Objective: To explore the expression of epidermal growth factor receptor(EGFR) protein during benzo(a)pyrene (BaP) induced carcinogenesis. Methods: This study, we firstly utilized immunofluorescence assay and Western-blot to examine EGFR expression of the BaP which was constructed previously by project team induced malignant transformation human bronchial epithelial cell (BTC) and the control (16HBE cell). Then, we selected 36 healthy SD rats, divided into two groups according to simple random method, 18 rats each group. The constructed rat lung neoplasm model induced by pulmonary injection of BaP (10 mg/ml of BaP solution in 0.2 ml corn oil), contrast group use 0.2 ml corn oil, lung tissue was collected and the EGFR expression of lung tissue was detected by immunofluorescence assay and Western blot. T analysis was used to test the different of EGFR between two groups. Results: Immunofluorescence analysis showed that the EGFR expression in BTC was significantly higher than 16HBE cell. Meanwhile, Western blot also was used to confirmed this result, the relative expression of EGFR protein in the rats of the model group the control group were 1.04±0.13 and 2.32±0.12, respectively, and the difference was statistically significance (t=12.39, P<0.001). In vivo, well-defined tumor was found in the rat with pulmonary injection of BaP, and the lung showed diffuse alveolar septal thickening, alveolar wall destruction and pulmonary alveoli fusion, which suggested that the rat lung neoplasm model was constructive successfully. Furthermore, we found the EGFR expression of lung was increased dramatically in the rat lung neoplasm model by immunofluorescence detection and Western blot. The relative expression of EGFR protein in the rats of the model group the control group were 0.21±0.03 and 1.30±0.07, respectively, and the difference was statistically significance (t=12.84, P<0.001). Conclusion Expression of EGFR protein was increased during BaP carcinogenesis, and EGFR may play an important role in the carcinogenesis of BaP.

Objective The ammonia level in air and heavy metals in drinking water were explored in a cynomolgus monkey feedlot. Methods Air ammonia from different communities and feeding patterns of cynomolgus monkeys were collected at three time-points per day and determined by Nessler's reagent spectrophotometry. Inductively coupled plasma mass spectrometry was applied to detect the level of heavy metals in drinking water from 5 different sampling sites in the feedlot,incluing the outlet of underground water,the water tank,both monkey cages equipped with PVC or iron pipes and sewage lagoon,respectively. Results Air ammonia levels in quarantine inspection flock cages(0.59 ± 0.03 mg/m3)were significantly higher than in the cages of both reproductive flock(0.34 ± 0.03 mg/m3)and sale flock(0.27 ± 0.04 mg/m3). The ammonia level in air in different feeding patterns ranks as following:cage rearing of quarantine inspection flock(0.59 ± 0.03 mg/m3)>cage rearing of reproductive flock(0.48 ± 0.02 mg/m3)>captive bleeding of sale flock(0.30 ± 0.02 mg/m3)>cage rearing of sale flock(0.25 ± 0.01 mg/m3)> captive bleeding of reproductive flock(0.22 ± 0.02 mg/m3). The air ammonia concentrations of both former flocks were statistically higher than the latter three flocks. The highest air ammonia level among different flocks and feeding patterns occurred in the morning, before waste discharge clean-up. The iron concentration in drinking water in the cages equipped with iron pipes was higher than Chinese drinking water standard. Conclusions The air ammonia level was lower than the Chinese air quality standard. The iron concentration in drinking water in the cages equipped with iron pipes was higher than the Chinese drinking water standard.

OBJECTIVETo investigate the effect of poly-ADP-ribosylation in hexavalent chromium Cr(VI) induced cell damage.

METHODSThe study object, poly (ADP-ribose) glycohydrolase (PARG) deficient human bronchial epithelial cells (16HBE cells), was constructed previously by our research group. Normal 16HBE cells and PARG-deficient cells were treated with different doses of Cr (VI) for 24 h to compare the differences to Cr (VI) toxicity, meanwhile set up the solvent control group. On this basis, 5.0 µmol/L of Cr (VI) was selected as the exposure dose, after the exposure treatment, total proteins of both cells were extracted for two dimension fluorescence difference gel electrophoresis (2D-DIGE) separation, statistically significant differential protein spots were screened and identified by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS/MS), and further validated by Western blot.

RESULTSAfter Cr (VI) treatment, the survival rate of PARG-deficient cells was higher than normal 16HBE cells. When the doses reached up to 5.0 µmol/L, the survival rate of 16HBE cells and PARG-deficient cells were respectively (59.67 ± 6.43)% and (82.00 ± 6.25)%, the difference between which was significant (t = -4.32, P < 0.05). 18 protein spots were selected and successfully identified after 2D-DIGE comparison of differential proteins between normal 16HBE cells and PARG-deficient cells before and after exposure. The function of those proteins was involved in the maintenance of cell shape, energy metabolism, DNA damage repair and regulation of gene expression. The differential expression of cofilin-1 was successfully validated by Western blot. The expression level of cofilin-1 in the 16HBE cells increased after Cr (VI) exposure with the relative expression quantity of 1.41 ± 0.04 in treated group and 1.00 ± 0.01 in control group, the difference of which was statistically significant (t = -18.00, P < 0.05), while the expression level in PARG-deficient cells had no statistically significant difference (t = -8.61, P > 0.05).

CONCLUSIONMost of the identified differential proteins are closely related to tumorigenesis, suggesting that poly-ADP-ribosylation reaction may resist the cytotoxicity of Cr(VI) by inhibiting Cr (VI) induced tumorigenesis, which provides important reference data to clarify the mechanisms of poly-ADP-ribosylation in Cr (VI) induced cell damage.

Bronchi ; Cell Transformation, Neoplastic ; genetics ; Chromium ; Cofilin 1 ; DNA Repair ; Epithelial Cells ; Glycoside Hydrolases ; deficiency ; physiology ; Humans ; Tandem Mass Spectrometry

Objective To investigate the application value of extracellular volume fraction(ECV)obtained from enhanced CT in diagnosis and classification of acute pancreatitis.Methods The clinical data from patients with acute pancreatitis(acute pancreatitis group)and normal controls(control group)underwent enhanced CT were analyzed retrospectively.The CT values of pancreas and abdominal aorta in the same sclice on precontrast and equilibrium-phase images were measured,and then pancreatic ECV was calcu-lated.The measured parameters were compared between the groups of control and acute pancreatitis,and subgroups of non-severe and severe pancreatitis.The logistic regression analysis was used to identify the risk factors for acute pancreatitis and severe pancrea-titis,and the receiver operating characteristic(ROC)curve was used to analyze the diagnostic efficiency in diagnosis and classifica-tion of acute pancreatitis.Results The pancreatic CT value and ECV were independent risk factors for acute pancreatitis(P＜0.05),and the ECV was an independent risk factor for severe pancreatitis(P＜0.05).The area under the curve(AUC)of ECV was higher in acute pancreatitis group(0.81)and severe pancreatitis subgroup(0.68).Conclusion As a quantitative parameter,the ECV obtained from enhanced CT has higher clinical application value and higher popularity in the diagnosis and classification of acute pancreatitis.