Decellularized tissue engineering scaffolds appear to have the properties of similar structure and mechanical characteristics to native tissues，good biocompatibility，suitability for cell adhesion，growth and angiogenesis induction，and non-immunogenicity. Genipin has anti-inflammatory，antithrombotic and antioxidative features which can considerably suppress vascular and endothelial inflammatory activation，increase mechanical strength of biological scaffolds，inhibit inflammatory response and decrease degradation rate of biological scaffolds. By cross-linking with decellularized matrices，Genipin can further improve corresponding performance of tissue engineering matrices，which is very helpful to promote the application of tissue engineering into clinical practice of cardiothoracic surgery. This review focuses on recent research process and possible prospects of Genipin cross-linking in tissue engineering in the field of cardiothoracic surgery.
Objective To study the release properties of basic fibroblast growth factor (bFGF) chitosan microspheres prepared by cross-linking-emulsion method using chitosan as a carrier material so as to lay a foundation for further study. Methods Using 0.6% sodium tripolyphosphate solution as a crosslinking agent and 1.5% solution of chitosan as a carrier material, bFGF chitosan microspheres were prepared by cross-linking-emulsion method. Laser particle size analyzer and Zeta electric potential analyzer were used to measure the particle diameter distribution, scanning electronic microscope to observe the morphology, and ELISA to determine the drug loading, the encapsulation rate, and the drug release properties. Results The particle size of bFGF chitosan microspheres ranged 20.312-24.152 μm. The microspheres were round with a smooth surface and uniform distribution, and it had no apparent porosity. The drug loading and encapsulation rate of microspheres were (7.57 ± 0.34) mg/g and 95.14% ± 1.58%, respectively. The bFGF chitosan microspheres could continuously release bFGF for 24 days; the bFGF level increased gradually with time and reached (820.45 ± 21.34) ng/mL at 24 days; and the microspheres had a burst effect, and the burst rate was 18.08%, and the accumulative release rate of the microspheres reached 82.05% during 24 days. Conclusion It is easy-to-operate to prepare the bFGF chitosan microspheres with the cross-linking-emulsion method. The bFGF chitosan microspheres have smooth surface, uniform distribution, and no apparent porosity.
Objective To review the recent advances of cross-linking reagent for producing hyaluronic acid(HA) derivative so as to provide more advice for thedevelopment of HA reagent. Methods Recent original articles related to the species, characteristic, cross-linking methodology and mechanism of the cross-linking reagent to producing HA derivative were summarized and systematically analyzed. Results The derivatives after special kinds of reagents modification would remain their own good biocompatibility and change their original rheololgical characterization and obtain relative long organism residence time. Conclusion Development of hyaluronic derivatives may widen their medical application.
ObjectiveTo review the research progress of novel cross-linking methods applied in bio-derived materials. MethodsThe literature about the latest progress in the cross-linking methods of bio-derived materials was reviewed and analyzed. ResultsThe novel cross-linking methods of the bio-derived materials can be divided into chemical methods, physical methods, and biological methods, whose available application and cross-linking properties are greatly depended on their mechanisms. So proper methods should be developed to meet the various application requirements of the materials. A series of studies shows the feasibility and availability of the cross-linked bio-derived materials in the repair and reconstruction of the tissue. ConclusionBio-derived materials modified by novel cross-linking methods are proved to obtain excellent biocompatibility and tissue repair ability, better mechanical properties and degradation properties, and so on. Those methods provide researchers more choices to cross-linking materials, which are help to obtain the clinical tissue engineering products.
ObjectiveTo investigate whether lysyl oxidase(LOX) has significant relation to persistent atrial fibrillation(AF) with mitral valvular diseases. MethodsWe included 184 consecutive lone mitral valvular disease patients who needed surgery in our hospital between March 2012 and February 2014. Patients who had persistent AF formed the AF group, and those who still kept sinus rhythm(SR) comprised the SR group. In the AF group, patients were separated into two groups by the subgroup of mitral valvular disease(mitral stenosis and mitral regurgitation), then formed a MS+AF group and a MR+AF group. There were 97 patients with 44 males and 53 females at age of 52.76±11.35 years in the AF group and 90 patients with 48 males and 42 females at age of 47.95±14.22 years in the SR group. Blood specimens were obtained from patients for the first time peripheral venous blood after admitted to hospital. LOX levels were measured by ELISA test kits of LOX. ResultsAF was diagnosed in 51.87%(97/187) of lone mitral valvular disease patients. Mitral stenosis patients were easy to have AF(60.31% vs. 34.43%, P<0.05). The plasma level of LOX was significantly higher in the AF group than that in the SR group(73.78±25.42 IU/L vs. 51.05±18.96 IU/L，P<0.05). In the AF group, the LOX level in the mitral stenosis group was higher than that in the mitral regurgitation group(84.21±32.15 IU/L vs. 59.74±35.21 IU/L， P<0.05). Mitral stenosis patients more frequently had a history of stroke than mitral regurgitation patients did. AF correlated significantly with the level of LOX(r=0.124， P=0.036) and left atrial dimension(r=0.531，P=0.042). ConclusionWe validate and extend the hypothesis that increasing LOX level predicts an increasing risk of AF in mitral valvular diseases. Lysine oxidase is a potential diagnostic biomarker for AF. It is expressed significantly in mitral stenosis patients with AF especially.