1.The role of protein kinase C to LPS-induced β-1,4-galactosyltransferase- Ⅰ expression in endothelial cells
Zhiyun BEN ; Chun CHENG ; Xiaolei SUN ; Ji QIAN ; Feng XIAO ; Dongmei ZHANG ; Yuhong JI
Chinese Journal of Microbiology and Immunology 2009;29(3):198-203
Objective To investigate the regulation of protein kinase C(PKC) to the expression of β-1,4-galactusyhransferase- Ⅰ ( β-1,4-GalT- Ⅰ ) and the influence on cytoskeleton and adherence ability of human umbilical vein endothelial cells(HUVECs) when stimulated by lipopolysaccharide (LPS). Methods Cultured HUVECs were pretreated by various PKC inhibitors or phorbol 12-myristate 13-acctate( PMA), an excitomotor of PKC respectively for 30 min, then stimulated by LPS for 4 h. β-1,4-GalT-Ⅰ expression were detected by RT-PCR and Western blot, expression of β-1,4-galactosylated carbohydrate chains and cytoskeleton were assayed by immumofluorescence, and adherence ability of HUVECs was observed by endothelialmonocyte cell adherence test. Results Up-regulated expression of β-1,4-GalT- Ⅰ and β-1,4-galactosylated carbohydrate chains in HUVECs stimulated by LPS were suppressed by PKC inhibitors and increased by PMA. F-actin and β-1,4-GalT- Ⅰ were partly co-localized in HUVECs. PKC inhibitor inhibited the effect of LPS on the distribution of F-actin and β-1,4-GalT- Ⅰ. Adherence ability of HUVECs enhanced by LPS was significantly suppressed by PKC inhibitor. Conclusion PKC signal transduction pathway may participate in regulating β-1,4-GalT-Ⅰ expression in endothelial cells stimulated by LPS. Furthermore, polytypes of PKC may participate in this regulating process; PKC might regulate cytoskeleton reorganization and adherence ability of EC through β-1,4-GalT-Ⅰ during inflammation.
2.Phosphorylcholine coating enhances biocompatibility of expanded polytetrafluoroethylene used in polymeric prosthetic heart valves
Ben ZHANG ; Dejun GONG ; Xiwu ZHANG ; Tongyi XU ; Lin HAN ; Hao TANG ; Fanglin LU ; Zhiyun XU
Chinese Journal of Tissue Engineering Research 2014;(34):5509-5514
BACKGROUND:Our preliminary study found that the monocusp valves made of ultramicropore expanded
polytetrafluoroethylene (ePTFE) revealed no significant thrombus, calcification, or degradation 20 weeks after implanted into the descending aorta and the left pulmonary artery in sheep, which verified the good property of ePTFE. However, the surface of ePTFE in the left pulmonary artery was covered with obvious neointima.
OBJECTIVE: To assess the biocompatibility of phosphorylcholine-coated ePTFE.
METHODS:ePTFE surface was modified by phosphorylcholine derivative. Then the changes of surface shape, tensile stress at yield and elasticity modulus, water contact angle, and protein absorption capacity of ePTFE after surface modification were observed. (1) Hemolytic test: the leaching solution of phosphorylcholine-coated ePTFE, leaching solution of uncoated ePTFE, normal saline, and distiled water were added to the diluted human blood, respectively. (2) Platelet count test: the phosphorylcholine-coated ePTFE, uncoated ePTFE, high density
polyethylene, and Zymosan A were added to the whole blood samples from healthy volunteers, respectively.
(3) Platelet activation test: the phosphorylcholine-coated ePTFE, uncoated ePTFE, γ-Globulins, and Zymosan A
were added to the whole blood samples from healthy volunteers, respectively.
RESULTS AND CONCLUSION: The mean micropore diameter of ePTFE was significantly decreased after
phosphorylcholine coating (P < 0.001). The hydrophilicity and the ability of suppressing protein adsorption were
significantly strengthened after phosphorylcholine coating (P < 0.001). Phosphorylcholine coating did not influence
ePTFE in biomechanical properties and hemolytic test. The platelet count test and platelet activation test demonstrated that phosphorylcholine coating significantly improved anti-thrombus function of ePTFE. So, phosphorylcholine coating can enhance anti-thrombus function, suppress protein adsorption, and improve biocompatibility of ePTFE.
3.Diagnosis and surgical treatment of cardiac tumors of the right ventricle
Ben ZHANG ; Tongyi XU ; Yang LIU ; Zhigang LI ; Lin HAN ; Zhiyun XU
Chinese Journal of Thoracic and Cardiovascular Surgery 2013;29(10):585-587
Objective To discuss the diagnosis and surgical treatment of the primary right ventricular tumors.Methods The results of surgical treatment of 7 patientss (5 males,2 females; median age,48 years,range,37 to 68 years) with primary right ventricular tumors hospitalized from Jan,1999 to May,2012 were analyzed.By preoperation echocardiography,cardiac myxoma was diagnosed in 2 cases,and cardiac space-occupying lesion was diagnosed in 5 cases.Median sternotomy were performed in all the 7 cases for biopsy or resection of tumor.when resection of tumor,extracorporeal circulation and cardiac arrest were performed.Results The 7 patients accounted for 4.96% of patients with cardiac tumors surgically treated in the corresponding period.Complete resection of tumor was performed in 5 cases,and only biopsy in 2 cases.The pathological diagnoses included myxoma in 2 cases,lipoma in 1 case,liomyoma in 1 case,undifferentiated sarcoma in 1 case,and mesenchymal sarcoma in 2 cases.There was no in-hospital death.During a follow-up of 1 ~ 51 months (median,38 months),the 3 cases of sarcoma died,and the other patients were good and showed no recurrence.Conclusion The incidence rate of primary right ventricular malignant tumor is relatively high.Echocardiography is the most important diagnosis method.The prognosis of right ventricular malignant tumor is poor.The results of surgical treatment of right ventricular benign tumor are satisfactory.
4.Transcatheter pulmonary valve replacement in sheep : 1-month evaluation of a novel polymeric prosthetic heart valve
Ben ZHANG ; Tongyi XU ; Xin LI ; Xiang CHEN ; Zhigang ZHANG ; Lin HAN ; Zhiyun XU
Chinese Journal of Thoracic and Cardiovascular Surgery 2014;30(4):238-241
Objective To evaluate valvular functionality after transcatheter pulmonary valve replacement in sheep using a novel polymeric prosthetic pulmonary valve.Methods In this study,we designed a novel polymeric trileaflet transcatheter pulmonary valve with a balloon-expandable stent,and the valve leaflet was made of 0.1 mm expanded polytetrafluoroethylene (ePTFE).We chose bovine pericardium valve as control.Pulmonary valve stents were implanted in situ by right ventricular apical approach in 8 healthy sheep(6 for polymeric valve and 2 for bovine pericardium valve) weighing an average of(22.8 ± 2.2) kg.Angiography was performed after implantation to assess immediate valvular function.Color Doppler echocardiography and 64-row computed tomography were used to assess valvular function 4 weeks after implantation.Results Implantation was successful in 8 sheep.Angiography at implantation showed one polymeric valve was located below the ideal position and most of the stent was in the outflow tract of right ventricle.While,all the other prosthetic valves demonstrated orthotopic position and exhibited normal open and close functionality.Echocardiography 4 weeks after implantation showed all the prosthetic valves exhibited normal functionality and no significant insufficiency.The peak-peak transvalvular pressure gradient of the polymeric valves was (18.8 ± 6.0) mmHg,while that of two bovine pericardium valves were 9 mmHg and 20 mmHg.CT 4 weeks after implantation demonstrated orthotopic position of the stents except the above-mentioned one and all the stents had no deformation.Conclusion The success rate of transcatheter pulmonary valve replacement by right ventricular apical approach is satisfactory.The early valvular functionality of the novel ePTFE pulmonary valve after transcatheter pulmonary valve replacement in sheep is good.
5.Transcatheter pulmonary valve replacement in sheep:medium-term evaluation of a novel polymeric prosthetic heart valve
Ben ZHANG ; Tongyi XU ; Xiang CHEN ; Xianyue WANG ; Guang TONG ; Xin LI ; Weida ZHANG ; Zhiyun XU
Chinese Journal of Thoracic and Cardiovascular Surgery 2017;33(12):747-751
Objective To evaluate medium-term valvular functionality after transcatheter pulmonary valve replacement in sheep using a novel polymeric prosthetic pulmonary valve(PPHV). Methods In this study, we designed a novel polymeric trileaflet transcatheter pulmonary valve with a balloon-expandable stent, and the valve leaflet was made of 0. 1mm expanded polytetrafluoroethylene( ePTFE) . We chose bovine pericardium valve as control. Pulmonary valve stents were implanted in situ by right ventricular apical approach in 12 healthy sheep(10 for polymeric valve and 2 for bovine pericardium valve) weighing anaverageof(22.1±2.3)kg. Echocardiography,angiography,64-rowcomputedtomography(CT),andautopsywereusedto assess valvular function 12 weeks after implantation. Results Two PPHVs failed to be implanted in situ of pulmonary valve po-sition. Implantation was successful in the other 10 sheep. One sheep died of pneumonia, and the other 9 sheep survived at the end of follow-up. Echocardiography 12 weeks after implantation showed all the PPHVs exhibited good functionality and no sig-nificant insufficiency. The peak-peak transvalvular pressure gradient of the PPHVs was(28.2 ±8.0)mmHg(16-38 mmHg) (1 mmHg=0. 133 kPa), while that of two bovine pericardium valves were 16 and 21 mmHg. Angiography and CT 12 weeks after implantation demonstrated orthotopic position and normal operation of the valves,and no deformation of the valved stents. Pathological examination of the explanted PPHVs 12 weeks after implantation showed no degradation or damage of the ePTFE leaflets and most of the leaflets were thin and pliable, without significant thrombus or calcification, while visible pannus over-growth was found at the bottom of the valve leaflets, in the commissural areas and on the sealing cuff. Conclusion The medi-um-term effects of the novel ePTFE pulmonary valve after transcatheter pulmonary valve implantation in sheep is good. The no-vel PPHV exhibits good anti-adhesion, anti-degradation, anti-thrombus, anti-calcification performance and good biomechanical property. The hemodynamic parameter of PPHV is comparable to bovine pericardium valve. Optimizing the valve design might eliminate the problem about pannus overgrowth.