RESUMO
Currently, as the key raw material of artificial biological heart valve, bovine pericardium is mainly depend on import and has become a "bottleneck" challenge, greatly limiting the development of domestic biological heart valve. Therefore, the localization of bovine pericardium is extremely urgent. In this study, the pericardium of Sichuan yak was compared with that of Australian cattle in terms of fundamental properties and anti-calcification performance. The results demonstrated that the appearance and thickness of yak pericardium were more advantageous than the Australian one. Sichuan yak pericardium and Australian cattle pericardium had comparable performance in shrinkage temperature, mechanical test and anti-calcification test. This study preliminarily verifies the feasibility of substitution of Australian cattle pericardium by Sichuan yak pericardium and promotes the progression of bovine pericardium localization with data support.
Assuntos
Animais , Bovinos , Austrália , Bioprótese , Próteses Valvulares Cardíacas , PericárdioRESUMO
Objective To explore the feasibility of the application of yak pericardium as anti-calcified heart valve materials in transcatheter aortic valve replacement (TAVR). Cattle pericardium and commercial Sino products were used as controls. Methods Yak and cattle pericardium was decellularized, and then the acellular extent was qualitatively and quantitatively analyzed with hematoxylin-eosin (HE) staining and DNA detection kit respectively. Two cross-linking agents, i.e. glutaraldehyde and genipin, were used to cross-link the acellular pericardium, respectively. After testing the mechanical property, thermodynamic stability and biocompatibility of the pericardium, the cross-linked pericardium was subcutaneously implanted in juvenile Wistar rats. After 2～4 weeks of the implantation, histological staining and tissue calcification analysis were conducted. Results The nuclei of the yak pericardium were almost invisible after decellularized treatment, and the DNA content decreased from (0.90±0.13)μg/mg to (0.09± 0.02)μg/mg that was significantly lower than that of Sino product (P<0.001). The mechanical strength of the acellular yak pericardium, glutaraldehyde or genipin cross-linked yak pericardium was higher than that of the cattle pericardium (all P<0.05). The maximum stress value, obtained in the glutaraldehyde cross-linked yak pericardium, was (8.44±2.61) MPa, which was higher than (7.92±1.81) MPa of the Sino product (P<0.05). The shrinkage temperature of non- and cross-linked yak pericardium was slightly higher than that of cattle pericardium, but difference was not statistically significant (all P>0.05). For the two cross-linked yak pericardium, the hemolysis rate and cell proliferation ratio was similar with that of cattle pericardium (all P>0.05), the tissue regeneration ability of subcutaneous implantations was inferior, and the calcification level was higher than that of cattle pericardium with an no statistically significant difference (all P>0.05). After 4 weeks of the subcutaneously implantation, the calcium content of the glutaraldehyde cross-linked pericardium was 32.62～65.49μg/mg. Conclusions Yak pericardium has better mechanical properties and thermodynamic stability than cattle pericardium, and the biocompatibility can meet the requirements of transcatheter aortic valve replacement.
RESUMO
Objective:To compare the properties between decellularized rabbit carotid artery with different cross-linked technologies.Methods:The decellularized rabbit carotid arteries were randomly divided into a photo-oxidation group and a procyanidins group.One group was cross-linked with photo-oxidation and the other group was cross-linked with procyanidins.The in vitro or in vivo properties of the two groups were evaluated by testing heat-shrinking temperature,max tensile strength and the max elongation or by testing tissue structure,inflammatory reaction and calcification degree.Results:The heat-shrinking temperature,max tensile strength and the max elongation were similar in the two groups (P＞0.05).The tissue structure and inflammatory reaction were also similar in the two groups.Mthough the result of Von-Kossa calcium salt stain was slightly different,the calcium content was lower in the procyanidins group than that in the photo-oxidation group (P＜0.05).Conclusion:The grafts by two cross-linked technologies show excellent mechanical capability,lower immunogenicity,good biological stability and anti-calcification ability.The procyanidins group shows a better anti-calcification property than the photo-oxidation group.
RESUMO
Calcification of silicone rubber is a pathologic mineralization phenomenon which occurs on the surface after it is implanted in vivo,and there is no effective prevention method.The important process of calcification including these steps:phosphate ions combined with calcium ions to promote nucleating aggregation,slow increasing,fusion,and gradually form a larger accumulation of hydroxyapatite calcium.The research had been developed to the level of cells and genes,such as matrix Gla protein clusters is a calcification inhibitor of the tissues around silastic prosthesis.It is necessary to obtain a theoretical breakthrough in the aspect of organic template modulation of inorganic crystals.Silicone elastomer having its own local anti-calcification property had been paid more attention.Fully revealing the mechanism of calcification and calcification-resistant of silicone rubber will probably provide the basis for building a new anti-calcification material.