BACKGROUND: After tissue-engineering products transplantation, angiogenesis played an important role in the function restoring of defective organs. The natural tissue-engineering materials had a wide application in tissue engineering due to its favorable biocompatibility and degradability, at the same time its pro-angiogenic function enhanced the achievement ratio of tissue-engineering products transplantation. Therefore, they attract much attention during recent years. OBJECTIVE: To summarize the research status of incubating induced angiogenesis of tissue-engineered natural scaffold, so as to give some theoretical basis for further study on clinical application of natural tissue engineering materials. METHODS: Relevant literatures in PubMed and Springerlink published between January1995 and June 2009 were searched by compute with the key words of "tissue-engineering products, natural materials" in English. While relevant Chinese articles in CKNI published between January1999 and June 2007 were also searched with the key words of "tissue-engineering natural materials, collagen, chitosan, fibrin" in Chinese. After primary selection, inclusive articles were those about study and experimental study of induced angiogenesis of tissue-engineered natural scaffold. Exclusive criteria: repetitive and obsolescent articles. A total 35 literatures were finally analyzed in accordance with the criteria. RESULTS AND CONCLUSION: The natural tissue engineering materials were synthesized by macromolecules out of normal tissue, whose multiple bioinformation provided signal for cells and benefited for cellular adhesion and maintenance. Collagen protein, fiber gel protein, and chitosan summarized in this study were beneficial for inducing angiogenesis but limited to mechanical characteristics. Therefore, to construct natural materials inducing angiogenesisis is prospect.

Some different membranes were prepared by Chitosan with the degree of deacetylation (DD) of 63.7%, 73.7%, 83% and 97% respectively. To study the biocompatibility of Chitosan membrane toward corneal stromal cells, the rabbit cells were cultured on the surface of different DD chitosan membranes. The morphological characteristics, the cell-adhesion, the cell proliferation and the activity of LDH in the medium were investigated. The results of experiment shows that the DD of Chitosan has very significant effect on the biocompatibility of Chitosan membrane toward corneal stromal cells. The more DD of Chitosan, the less injury was made to corneal stromal cells by the chitosan membrane, which is favor of the growing and adhesion of corneal stromal cells. The biocompatibility of the membrane made with low DD Chitosan with corneal stromal cells became worse.
Acetylation ; Animals ; Biocompatible Materials ; chemistry ; pharmacology ; Cell Adhesion ; drug effects ; Cell Division ; drug effects ; Chitosan ; chemistry ; pharmacology ; Cornea ; cytology ; Materials Testing ; Membranes, Artificial ; Rabbits ; Stromal Cells ; drug effects

Objective: To assess the efficacy and safety of thrombolytic treatment with reteplase in patients with intermediate-risk acute pulmonary embolism. Methods: Ten consecutive patients with intermediate-risk acute pulmonary embolism who received thrombolytic treatment with reteplase at Thrombosis and Vascular Medicine Center, Fuwai Hospital from March to November in 2016 were included.Vital signs, right ventricular diameter, systolic pulmonary artery pressure, and biochemical markers were assessed before and after thrombolytic therapy with reteplase, and bleeding complications were also observed during 3 months follow up. Results: (1) For the efficacy outcomes: at 48 hours after thrombolytic treatment with reteplase, echocardiography-derived diameter of right ventricular was significant reduced from (27.9±3.8) mm to (24.8±2.6) mm (P=0.03), systolic pulmonary artery pressure decreased from (63.9±21.6) mmHg(1 mmHg=0.133 kPa) to (34.4±19.8) mmHg (P=0.02). Heart rate and breathing rate were also decreased significantly (both P<0.05), blood pressure remained unchanged post therapy.Hypoxemia was quickly corrected with an significant elevation of PaO₂ and SaO₂ ((65.2±14.3) mmHg vs. (80.0±9.6) mmHg, P=0.006; (90.8±3.5)% vs. (95.2 ±1.6)%, P=0.002 respectively). PaCO₂ was also increased significantly (P<0.05). Serum NT-proBNP and cTnI were decreased significantly (both P<0.05). There was no recurrent pulmonary embolism or deep-vein thrombosis during the 3 months follow-up. (2) For the safety outcomes: a thrombolytic relevant hemoptysis (about 70 ml) occurred in 1 patient, and was controlled by PCC therapy.No other clinically relevant events were observed during thrombolytic treatment. Eight patients were followed more than 3 months, there was no major bleeding complication or death during the follow up period. Conclusion Treatment of intermediate-risk acute pulmonary embolism with reteplase is effective and safe and there are no obvious side effects.