Yu G.-D.,Tianjin Medical University |
Li T.,Third Center Hospital of Tianjin |
Gao W.-Q.,Third Center Hospital of Tianjin |
Yu M.-L.,Key Laboratory of Artificial Cells |
And 3 more authors.
Chinese Journal of Tissue Engineering Research | Year: 2013
BACKGROUND: Dexamethasone as coating is fixed to the surface of cardiopulmonary bypass pipe, which can maintain sustainable anti-inflammatory effects and avoid adverse reactions due to excessive blood concentration, thereby maximizing the anti-inflammatory action of dexamethasone. OBJECTIVE: To develop a new coating method of dexamethasone sodium phosphate, which has anticoagulation activity, and to evaluate the performance of the coated pipeline, including the stability, anticoagulant and antiplatelet activity. METHODS: The surface of polyvinyl chloride pipelines in the extracorporeal circulation was successively pretreated with strong sulfuric acid and polyethylene imines. Dexamethasone sodium phosphate coated pipelines were made through two methods: ionic blond and premix. Then, a quantitative analysis was performed to evaluate anticoagulation, antiplatelet, resistance of protein adhesion and antithrombosis function. Non-coated polyvinyl chloride pipeline served as control group. RESULTS AND CONCLUSION: The biggest drug loadings were (2.06 ±0.68) and (3.33±0.75) μg/cm2 for dexamethasone sodium phosphate coated polyvinyl chloride pipelines prepared by premix and ionic blond, respectively. In the anticoagulation, antiplatelet, and resistance of protein adhesion experiment, dexamethasone sodium phosphate coated polyvinyl chloride pipelines prepared by premix were superior to those prepared by ionic blond and control group (P < 0.05). Release in vitro experiment showed that dexamethasone sodium phosphate coated polyvinyl chloride pipelines prepared by premix were also superior to those prepared by ionic blond. The findings indicate that the dexamethasone sodium phosphate coating prepared by premix shows better release and anticoagulation performance, as well as forms antiplatelet adhesion and antithrombosis function, to meet the short-term extracorporeal circulation requirements.
Yu M.-L.,Third Center Hospital of Tianjin |
Du Z.,Third Center Hospital of Tianjin |
Han T.,Third Center Hospital of Tianjin |
Wang Y.-R.,Third Center Hospital of Tianjin |
And 4 more authors.
Chinese Journal of Tissue Engineering Research | Year: 2013
Background: During the three-dimensional culture in vitro, hepatocytes can grow well in the pores of the scaffold, but enzymatic digestion for decellularization severely affects cell survival rate and activity. Objective: To prepare a macroporous scaffold, N-poly-isopropyl acrylamide-aldehyde seaweed polysaccharides, and to investigate the feasibility of this scaffold as a cell carrier for artificial liver bioreactor. Methods: Sodium alginate as the porogen was used to synthesize the macroporous N-poly-isopropyl acrylamide that was then cross-linked with aldehyde seaweed polysaccharides to prepare the macroporous three-dimensional cytoskeleton. Scaffold aperture and porosity were measured. (1) Cytotoxicity test: 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to detect absorbance values of mouse fibroblasts cultured in fresh cell culture medium, high-density polyethylene extract, high-density polyvinyl chloride extract and N-poly-isopropyl acrylamide-aldehyde seaweed polysaccharide extract. (2) Non-enzymatic acellular performance tests: The third generation of mouse fibroblasts cell line was inoculated into 6-well plates containing N-poly isopropylacrylamide-aldehyde seaweed polysaccharide scaffolds. In the experimental group, cells were recovered by cooling desorption, while in the control group, the cells were recovered using trypsin digestion method. Results and Conclusion: The aperture and porosity of the macroporous scaffold were (180.23±62.30) μm and (89.67±2.40)%, respectively. Cytotoxicity test showed that the macroporous scaffold of N-poly-isopropyl acrylamide-aldehyde seaweed polysaccharide had no cytotoxicity. The cell survival rate in the experimental group was increased 26.24% than that in the control group. These findings indicate that the three-dimensional macroporous cytoskeleton, N-poly-isopropyl acrylamide-aldehyde seaweed polysaccharide, has a macroporous structure suitable for cell growth, and thermo-responsive acellular performance overcomes cellular damage resulting from traditional enzymatic digestion and promotes the number of quality of cultured cells.
Zhang S.-H.,Third Center Hospital of Tianjin |
Feng Q.-S.,Third Center Hospital of Tianjin |
Lian F.,Third Center Hospital of Tianjin |
Gao X.-J.,Third Center Hospital of Tianjin |
And 2 more authors.
Chinese Critical Care Medicine | Year: 2013
Objective: To trace pressure-volume curves (P-V curves) with quasi-static technique in acute respiratory distress syndrome (ARDS) patients, and using it to explain the relationship between the end point of the expiratory limb and the change in the dead space of expiration. Methods: A prospective study was conducted. Fourteen ARDS patients receiving mechanical ventilation were included in the study. When P-V curves was traced with quasi-static technique, the spirometer was connected to the flow sensor. The start point of the expiratory limb was defined as tidal volume 1 (VT1) and the end point as V T2, and the difference between them (ΔVT=V T1-VT2) was calculated. The VT of spirometer (named VT3) and the predetermined VT (VT4) were recorded. Correlations of ΔVT and VT3, as well as VT4 and VT1, were analyzed with correlation analysis. Results: ΔVT was (417.40 ± 119.68) ml, and V T3 was (399.29 ± 121.36) ml, ΔVT and V T3 showed a good correlation (r=0.99, P=0.000), demonstrating that the ΔVT of the expiratory limb was correlated with the volume trapped in lung. VT4 was (908.21 ± 106.52) ml, and V T1 was (892.26 ± 106.32) ml, and they showed a good correlation (r=0.99, P=0.000). Conclusion: Because of part of the gas trapped at the end of expiration in ARDS patients, the dead space is increased, showing that the expiratory limb of the P-V curve cannot return to the base points, and the ΔVT of the expiratory limb is inversely proportional to the gas volume trapped in lung.