OBJECTIVE: To evaluate the characteristics and application prospect of tissue-engineered blood vessel stent materials. METHODS: Using "tissue engineering, tissue engineering blood vessel, intravascular stent" both in Chinese and English as key words to search documents published between January 1993 and October 2009. Literatures concerning biomaterials and tissue engineered blood vessel were included. Repetitive research or Meta analysis was excluded. After selection, 30 documents were included to discuss the kinds and characteristics of tissue-engineered blood vessel materials. RESULTS: Cellular tissue matrix is a kind of ideal material for intravascular engineering, which had widely applied in tissue-engineered stent. The fibrin-based stents are characterized by good biocompatibility, biodegradation, compatibility, as well as promote vascularization and tissue repair. Gelatin can implement its own "vascularization" due to less antigenicity and can be fully biodegraded. Accordingly, both the natural biomaterials and synthetic polymeric material have certain limitations, thus, the combination of these two materials would construct a tissue-engineered blood vessel stent that has good characteristics.Nano-modifled technology is hopeful to be applied in the future transplantation of tissue-engineered blood vessel stent.CONCLUSION: The tissue-engineered blood vessel developed rapidly in these years. However, as yet, there is not an ideal intravascular stent material. The natural biomaterials arose more attention, but the mechanical function of which is far from the stent requirement. Thus, to reach the aims of repair and reconstruction, new materials are the urgent need in tissue-engineered intravascular stent.

Objective To assess apoptosis mediated by the cell death receptor Fas in peripheral T lymphocytes of patients with abdominal aortic aneurysm. Methods The apoptotic pathway was triggered by anti-Fas monoclonal antibody in cultured and activated peripheral T-cells from 20 AAA patients. Control groups consisted of 15 patients with aortic atherosclerotic occlusive disease(AOD)and 25 healthy individuals. Cell survival and death rate were assessed. Results Cross-linkage of Fas receptor exerted a strong apoptotic response on T cells from AOD patients and healthy controls, while the effect on T cells was very limited from that of AAA patients. The evaluation of cell Survival rate showed a significantly higher percentage in AAA group(98.9%±10.3%)than in the AOD subjects(58.9%±15.2%)or the healthy group(59.4%±12.9%;P＜0.001＝.Apoptosis assessment by annexin V and propidium iodide staining and flow cytometry showed similar results. The defect in AAA group was not due to decreased fas expressed at normal levels. Moreover,it specifically involved the Fas system because cell death was induced in the normal way by methylprednisolone. Conclusions Fas-induced apoptosis in activated T cell from AAA patients is impaired. This may disturb the normal down-regulation of the immune response and thus provide a new insight into possible mechanisms and routes in the pathogenesis of AAA.

Changes in structure of oral solid dosage forms (OSDF) elementally determine the drug release and its therapeutic effects. In this research, synchrotron radiation X-ray micro-computed tomography was utilized to visualize the 3D structure of enteric coated pellets recovered from the gastrointestinal tract of rats. The structures of pellets in solid state and in vitro compendium media were measured. Pellets in vivo underwent morphological and structural changes which differed significantly from those in vitro compendium media. Thus, optimizations of the dissolution media were performed to mimic the appropriate in vivo conditions by introducing pepsin and glass microspheres in media. The sphericity, pellet volume, pore volume and porosity of the in vivo esomeprazole magnesium pellets in stomach for 2 h were recorded 0.47, 1.55 × 10⁸ μm³, 0.44 × 10⁸ μm³ and 27.6%, respectively. After adding pepsin and glass microspheres, the above parameters in vitro reached to 0.44, 1.64 × 10⁸ μm³, 0.38 × 10⁸ μm³ and 23.0%, respectively. Omeprazole magnesium pellets behaved similarly. The structural features of pellets between in vitro media and in vivo condition were bridged successfully in terms of 3D structures to ensure better design, characterization and quality control of advanced OSDF.