ISSN:0009-7322    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

BackgroundBlood flow characteristics influence endothelial cell apoptosis. However, little is known about the occurrence of endothelial cell apoptosis in human atherosclerosis and its relation to blood flow.Methods and ResultsA total of 42 human carotid atherosclerotic plaques were retrieved by endarterectomy; they were examined in the longitudinal axial direction. Plaques were included in this study when upstream and downstream parts were clearly visible, occlusion was absent, and immunostaining for luminal endothelium was present all along the plaque. Using these criteria, 13 plaques were processed for further immunohistochemical studies (using anti-CD31, anti-Ki-67, and anti-splicing factor antibodies) and in situ detection of apoptosis (terminal dUTP nick end-labeling and ligase assay). Eight plaques showed ≥1 apoptotic endothelial cell at the luminal surface. Quantitative analysis of endothelial cell apoptosis in these plaques showed a systematic preferential occurrence of apoptosis in the downstream parts of plaques, where low flow and low shear stress prevail, in comparison with the upstream parts (18.8±3.3% versus 2.7±1.2%, respectively,P<0.001). Endothelial cell apoptosis was barely detectable in plaque microvessels.ConclusionsOur results suggest that in vivo local shear stress influences luminal endothelial cell apoptosis and may be a major determinant of plaque erosion and thrombosis.

ISSN:0009-7322    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

BackgroundA high restenosis rate has been reported at the edges (“edge restenosis”) of32P radioactive stents with an initial activity level of 3 to 12 &mgr;Ci. This edge effect might be due to balloon injury and to a low dose of radiation at the stent margins. The aim of this study was to evaluate whether the implantation of32P radioactive stents with a higher activity level (12 to 21 &mgr;Ci) combined with a nonaggressive stent implantation strategy could solve the problem of edge restenosis.Methods and ResultsWe compared the results of lesions treated with single radioactive BX stents with an activity of 12 to 21 &mgr;Ci (group 2, n=54 lesions) with the results of lesions treated by single radioactive BX stents with an initial activity level of 3 to 12 &mgr;Ci (group 1, n=42 lesions). There were no procedural events. At the 6-month follow-up, no myocardial infarctions, deaths, or stent thromboses had occurred. Intrastent binary restenosis was 0% in group 1 versus 4% in group 2 (n=2, both at the ostium of the right coronary artery,P=NS). Intrastent neointimal hyperplasia was significantly lower in group 2 than in group 1. The intralesion (intrastent plus peri-stent) restenosis rate was 38% in group 1 versus 30% in group 2 (P=NS).ConclusionsSingle32P radioactive stents with an initial activity level of 12 to 21 &mgr;Ci reduced intrastent neointimal hyperplasia compared with stents of 3 to 12 &mgr;Ci, but they did not solve the problem of edge restenosis, even if a nonaggressive stent implantation strategy was used.

ISSN:0009-7322    

出版商:OVID    

年代:2000

数据来源: OVID