Objective: To validate the hypothesis that camel pericardium could be more protected than bovine pericardium against calcification process according to the huge difference in their respective lifestyle and lifetime. M...Objective: To validate the hypothesis that camel pericardium could be more protected than bovine pericardium against calcification process according to the huge difference in their respective lifestyle and lifetime. Methods: Glutaraldehyde (GA) fixed bovine and camel pericardium samples (BP and CP respectively) were both implanted in 30 New Zealand white rats (2 BP and 2 CP matched specimens in each animal) and explanted after 60 days. Unimplanted GA-fixed samples of both species served as control. Matched implanted samples and unimplanted samples were randomly submitted to elemental analysis by spectroscopy, phospholipid extraction, macroscopic and X-ray examination and histology. Results: At 60 days, calcium and phosphorus content were respectively 9.54% ± 3.1% and 4.79% ± 1.4% of tissue dry weight in BP, and 12.52% ± 2.7% and 6.14% ± 1.3% of tissue dry weight in CP (ns). In X-ray analysis, the calcification score was 1.28 ± 0.45 and 2.14 ± 0.98 in BP and CP samples respectively without significant difference (p < 0.08). In histology, calcifications were lower in BP than in CP: 1.37 ± 0.85 vs 2.28 ± 0.83 (ns);collagen fibers were better conserved in BP than in CP: 2.4 ± 0.48 vs 1.87 ± 0.78 (ns), and less disoriented: 25% vs 62% (ns). In unimplanted samples, there was a higher but not significant rate of extracted lipids in CP: 5.7 ± 1.8 vs 9.5 ± 3.8 nanomoles in PS fraction and 11.3 ± 3.7 vs 19 ± 7.7 nanomoles in total fatty acids, in BP and CP samples respectively. All results were in conjunction and demonstrated a higher but not significant rate of mineralization in camel pericardium after implantation, which could be related to a higher but not significant basic rate of phospholipid and fatty acids. Conclusion: This experiment study in a subcutaneous rat model has failed to valid our hypothesis. Because the differences observed between bovine and camel pericardium did not reach the significance, at the best, there is no difference between both species and at the worst, camel pericardium has a higher rate of the phosphatidylserine fraction of phospholipid, and is more sensitive and prompt to calcification.展开更多
The lifespan of biological heart valve prostheses available in the market is limited due to structural alterations caused by calcium phosphate deposits formed from blood plasma in contact with the tissues.The objectiv...The lifespan of biological heart valve prostheses available in the market is limited due to structural alterations caused by calcium phosphate deposits formed from blood plasma in contact with the tissues.The objective of this work is to present a comparative methodology for the investigation of the formation of calcium phosphate deposits on bioprosthetic and tissue-engineered scaffolds in vitro and the influence of mechanical forces on tissue mineralization.Based on earlier investigations on biological mineralization at constant supersaturation,a circulatory loop simulating dynamic blood flow and physiological pressure conditions was developed.The system was appropriately adapted to evaluate the calcification potential of decellularized(DCV)and glutaraldehyde-fixed(GAV)porcine aortic valves.Results indicated that DCV calcified at higher,statistically nonsignificant,rates in comparison with GAV.This difference was attributed to the tissue surface modifications and cell debris leftovers from the decellularization process.Morphological analysis of the solids deposited after 20 h by scanning electron microscopy in combination with chemical microanalysis electron-dispersive spectroscopy identified the solid formed as octacalcium phosphate(Ca8(PO4)6H2·5H2O,OCP).OCP crystallites were preferentially deposited in high mechanical stress areas of the test tissues.Moreover,GAV tissues developed a significant transvalvular pressure gradient increase past 36 h with a calcium deposition distribution similar to the one found in explanted prostheses.In conclusion,the presented in vitro circulatory model serves as a valuable prescreening methodology for the investigation of the calcification process of bioprosthetic and tissue-engineered valves under physiological mechanical load.展开更多
When calcium phosphate forms in soft tissues such as blood vessels and heart valves, it causes disease. The abnormal formation of calcium phosphate is called pathogenic mineralization or pathogenic calcification. Cas...When calcium phosphate forms in soft tissues such as blood vessels and heart valves, it causes disease. The abnormal formation of calcium phosphate is called pathogenic mineralization or pathogenic calcification. Cases of rheumatic heart disease （RHD） always occur with fibrotic and calcified tissue of heart valve. In this article, samples taken from calcified human heart wdves were studied. The characterization was performend by scanning electronic microscope, X-ray Diffraction and transmission electron microscopy with selective diffraction patterns. It is found for the first time that calcium phosphate grains existing in the calcified human heart valves contain octacalcium phosphate （ OCP ）.展开更多
Objectives To investigate the effects of epoxy chloropropan on the expression of matrix metalloproteinases-9 (MMP-9) in creating tissue engineered heart valves (TEHV),on the tissue structures of TEHV,and to study the ...Objectives To investigate the effects of epoxy chloropropan on the expression of matrix metalloproteinases-9 (MMP-9) in creating tissue engineered heart valves (TEHV),on the tissue structures of TEHV,and to study the effects of epoxy chloropropan on the calcification of TEHV.Methods The porcine aortic valve leaflets were digested and decellularized by using detergent and trypsin.Those treated with 0.3% glutaraldehyde for 48 hours were the control group;those treated with 3% epoxy chloropropan for 24 hours were the experimental group.The cultured human bone marrow mesenchymal stem cells (hBMSCs) were seeded onto the decellularized scaffolds of TEHV.The histological studies were done with pathological sections and scanning electron microscopy.and reverse transcriptase-polymerase chain reaction (RT-PCR) were used to detect the expression of MMP-9.Results In the experimental group,the histology showed that the BMSCs grew well into the pores and formed a confluent layer in decellularized scaffolds;RT-PCR indicated significantly attenuated expressions of MMP-9,compared with the control(P<0.05).Conclusion The decellularized porcine aortic valves treated with 3% epoxy chloropropan may inhibit the expression of MMP-9;therefore epoxy chloropropan may prevent the calcification of tissue engineered heart valves.展开更多
目的探讨老年钙化性心脏瓣膜病患者颈动脉斑块积分(Crouse积分)、内膜中层厚度(intima media thickness,IMT)与瓣膜钙化程度的关系。方法回顾性分析2020年4月至2023年3月收治的106例老年钙化性心脏瓣膜病患者的临床资料(观察组)。另选...目的探讨老年钙化性心脏瓣膜病患者颈动脉斑块积分(Crouse积分)、内膜中层厚度(intima media thickness,IMT)与瓣膜钙化程度的关系。方法回顾性分析2020年4月至2023年3月收治的106例老年钙化性心脏瓣膜病患者的临床资料(观察组)。另选择90例颈动脉粥样硬化的非心脏瓣膜病患者作为对照组1、选取95例非老年钙化性心脏瓣膜病患者作为对照组2。单因素方差分析检验三组Crouse积分、IMT、管腔狭窄程度及老年钙化性心脏瓣膜病不同心瓣膜钙化程度患者Crouse积分、IMT。Pearson分析Crouse积分、IMT与心瓣膜钙化程度的相关性;受试者工作特征(ROC)曲线分析Crouse积分、IMT对老年钙化性心脏瓣膜病患者瓣膜钙化的预测价值。结果观察组Crouse积分、IMT、管腔狭窄程度均明显高于对照组1和对照组2(P<0.05)。老年钙化性心脏瓣膜病不同心瓣膜钙化程度患者Crouse积分、IMT比较:1级<2级<3级(P<0.05)。相关性分析结果显示,Crouse积分、IMT与老年钙化性心脏瓣膜病瓣膜钙化程度均呈明显正相关关系(r=0.585、0.623,P<0.05)。绘制Crouse积分、IMT预测老年钙化性心脏瓣膜病患者瓣膜钙化的ROC曲线示,Crouse积分、IMT联合预测的AUC为0.802(95%CI为0.738~0.867),明显高于各指标单一预测的AUC,最佳诊断敏感度和特异度分别为0.887、0.794(P<0.05)。结论老年钙化性心脏瓣膜病患者Crouse积分、IMT存在异常增高,且与瓣膜钙化程度呈正相关,测量上述指标有助于对心脏瓣膜钙化程度进行评估。展开更多
Objective To investigate the prevalence rate of heart valve calcification and its relativity with pathological changes and clinical pathogenic factors in elder patients at autopsy.Methods Pathology data at autopsy of ...Objective To investigate the prevalence rate of heart valve calcification and its relativity with pathological changes and clinical pathogenic factors in elder patients at autopsy.Methods Pathology data at autopsy of 1047patients with age from 60 to 106 years in Beijing Hospital from November 1954 to March 2016 were collected.Cases of heart valve calcification verified at autopsy展开更多
文摘Objective: To validate the hypothesis that camel pericardium could be more protected than bovine pericardium against calcification process according to the huge difference in their respective lifestyle and lifetime. Methods: Glutaraldehyde (GA) fixed bovine and camel pericardium samples (BP and CP respectively) were both implanted in 30 New Zealand white rats (2 BP and 2 CP matched specimens in each animal) and explanted after 60 days. Unimplanted GA-fixed samples of both species served as control. Matched implanted samples and unimplanted samples were randomly submitted to elemental analysis by spectroscopy, phospholipid extraction, macroscopic and X-ray examination and histology. Results: At 60 days, calcium and phosphorus content were respectively 9.54% ± 3.1% and 4.79% ± 1.4% of tissue dry weight in BP, and 12.52% ± 2.7% and 6.14% ± 1.3% of tissue dry weight in CP (ns). In X-ray analysis, the calcification score was 1.28 ± 0.45 and 2.14 ± 0.98 in BP and CP samples respectively without significant difference (p < 0.08). In histology, calcifications were lower in BP than in CP: 1.37 ± 0.85 vs 2.28 ± 0.83 (ns);collagen fibers were better conserved in BP than in CP: 2.4 ± 0.48 vs 1.87 ± 0.78 (ns), and less disoriented: 25% vs 62% (ns). In unimplanted samples, there was a higher but not significant rate of extracted lipids in CP: 5.7 ± 1.8 vs 9.5 ± 3.8 nanomoles in PS fraction and 11.3 ± 3.7 vs 19 ± 7.7 nanomoles in total fatty acids, in BP and CP samples respectively. All results were in conjunction and demonstrated a higher but not significant rate of mineralization in camel pericardium after implantation, which could be related to a higher but not significant basic rate of phospholipid and fatty acids. Conclusion: This experiment study in a subcutaneous rat model has failed to valid our hypothesis. Because the differences observed between bovine and camel pericardium did not reach the significance, at the best, there is no difference between both species and at the worst, camel pericardium has a higher rate of the phosphatidylserine fraction of phospholipid, and is more sensitive and prompt to calcification.
基金This research was funded by the People Program(Marie Curie Actions)of the European Union’s Seventh Framework FP7/2007–2013/under REA grant agreement n°317512.
文摘The lifespan of biological heart valve prostheses available in the market is limited due to structural alterations caused by calcium phosphate deposits formed from blood plasma in contact with the tissues.The objective of this work is to present a comparative methodology for the investigation of the formation of calcium phosphate deposits on bioprosthetic and tissue-engineered scaffolds in vitro and the influence of mechanical forces on tissue mineralization.Based on earlier investigations on biological mineralization at constant supersaturation,a circulatory loop simulating dynamic blood flow and physiological pressure conditions was developed.The system was appropriately adapted to evaluate the calcification potential of decellularized(DCV)and glutaraldehyde-fixed(GAV)porcine aortic valves.Results indicated that DCV calcified at higher,statistically nonsignificant,rates in comparison with GAV.This difference was attributed to the tissue surface modifications and cell debris leftovers from the decellularization process.Morphological analysis of the solids deposited after 20 h by scanning electron microscopy in combination with chemical microanalysis electron-dispersive spectroscopy identified the solid formed as octacalcium phosphate(Ca8(PO4)6H2·5H2O,OCP).OCP crystallites were preferentially deposited in high mechanical stress areas of the test tissues.Moreover,GAV tissues developed a significant transvalvular pressure gradient increase past 36 h with a calcium deposition distribution similar to the one found in explanted prostheses.In conclusion,the presented in vitro circulatory model serves as a valuable prescreening methodology for the investigation of the calcification process of bioprosthetic and tissue-engineered valves under physiological mechanical load.
文摘When calcium phosphate forms in soft tissues such as blood vessels and heart valves, it causes disease. The abnormal formation of calcium phosphate is called pathogenic mineralization or pathogenic calcification. Cases of rheumatic heart disease （RHD） always occur with fibrotic and calcified tissue of heart valve. In this article, samples taken from calcified human heart wdves were studied. The characterization was performend by scanning electronic microscope, X-ray Diffraction and transmission electron microscopy with selective diffraction patterns. It is found for the first time that calcium phosphate grains existing in the calcified human heart valves contain octacalcium phosphate （ OCP ）.
文摘Objectives To investigate the effects of epoxy chloropropan on the expression of matrix metalloproteinases-9 (MMP-9) in creating tissue engineered heart valves (TEHV),on the tissue structures of TEHV,and to study the effects of epoxy chloropropan on the calcification of TEHV.Methods The porcine aortic valve leaflets were digested and decellularized by using detergent and trypsin.Those treated with 0.3% glutaraldehyde for 48 hours were the control group;those treated with 3% epoxy chloropropan for 24 hours were the experimental group.The cultured human bone marrow mesenchymal stem cells (hBMSCs) were seeded onto the decellularized scaffolds of TEHV.The histological studies were done with pathological sections and scanning electron microscopy.and reverse transcriptase-polymerase chain reaction (RT-PCR) were used to detect the expression of MMP-9.Results In the experimental group,the histology showed that the BMSCs grew well into the pores and formed a confluent layer in decellularized scaffolds;RT-PCR indicated significantly attenuated expressions of MMP-9,compared with the control(P<0.05).Conclusion The decellularized porcine aortic valves treated with 3% epoxy chloropropan may inhibit the expression of MMP-9;therefore epoxy chloropropan may prevent the calcification of tissue engineered heart valves.
文摘目的探讨老年钙化性心脏瓣膜病患者颈动脉斑块积分(Crouse积分)、内膜中层厚度(intima media thickness,IMT)与瓣膜钙化程度的关系。方法回顾性分析2020年4月至2023年3月收治的106例老年钙化性心脏瓣膜病患者的临床资料(观察组)。另选择90例颈动脉粥样硬化的非心脏瓣膜病患者作为对照组1、选取95例非老年钙化性心脏瓣膜病患者作为对照组2。单因素方差分析检验三组Crouse积分、IMT、管腔狭窄程度及老年钙化性心脏瓣膜病不同心瓣膜钙化程度患者Crouse积分、IMT。Pearson分析Crouse积分、IMT与心瓣膜钙化程度的相关性;受试者工作特征(ROC)曲线分析Crouse积分、IMT对老年钙化性心脏瓣膜病患者瓣膜钙化的预测价值。结果观察组Crouse积分、IMT、管腔狭窄程度均明显高于对照组1和对照组2(P<0.05)。老年钙化性心脏瓣膜病不同心瓣膜钙化程度患者Crouse积分、IMT比较:1级<2级<3级(P<0.05)。相关性分析结果显示,Crouse积分、IMT与老年钙化性心脏瓣膜病瓣膜钙化程度均呈明显正相关关系(r=0.585、0.623,P<0.05)。绘制Crouse积分、IMT预测老年钙化性心脏瓣膜病患者瓣膜钙化的ROC曲线示,Crouse积分、IMT联合预测的AUC为0.802(95%CI为0.738~0.867),明显高于各指标单一预测的AUC,最佳诊断敏感度和特异度分别为0.887、0.794(P<0.05)。结论老年钙化性心脏瓣膜病患者Crouse积分、IMT存在异常增高,且与瓣膜钙化程度呈正相关,测量上述指标有助于对心脏瓣膜钙化程度进行评估。
文摘Objective To investigate the prevalence rate of heart valve calcification and its relativity with pathological changes and clinical pathogenic factors in elder patients at autopsy.Methods Pathology data at autopsy of 1047patients with age from 60 to 106 years in Beijing Hospital from November 1954 to March 2016 were collected.Cases of heart valve calcification verified at autopsy
