[Show abstract][Hide abstract] ABSTRACT: Whether the low molecular weight heparin microcapsule coated occluder is helpful to endothelialization in atrial-septal defect models is uncertain. This study aimed to investigate the best conditions for low molecular weight heparin coated NiTi alloy occluder and provide the evidence of the efficacy and safety of atrial-septal defect occluders in vivo.
Low molecular weight heparin microcapsules were investigated using gelatin as microcapsule material. The prepared low molecular weight heparin gelatin particles were subjected to nickel and titanium alloy occluder coating by sodium hyaluronate. A dog model of atrial septal defects was established after treatment with low molecular weight heparin microcapsule coated occluder (n = 4) and uncoated occluder (n = 4). Endotheliocytes and fibroblastic cells in occluders were observed. And the rate of endothelialization was detected.
When the concentration of gelatin was 1%, the diameters of particles were mostly about 100 microm, and the particle size was uniform. The envelope efficiency of low molecular weight heparin microcapsule was about 80%. The endothelialization of occluder in the model was more obvious in the coated group than in the uncoated group (P < 0.0001).
Low molecular weight heparin can be prepared into microcapsules with their particle size in nanometric grade. The antithrombotic properties are kept in the nickel and titanium alloy occluder successfully coated with sodium hyaluronate. The endothelialization after the interventional occlusion in the coated group is obvious, indicating that low molecular weight heparin is helpful to the growth of endothelial cells in the occlude and the healing after the interventional occlusion.
Preview · Article · Jun 2009 · Chinese medical journal
[Show abstract][Hide abstract] ABSTRACT: To investigate the in vivo gene expression of adenovirus-mediated human tissue factor pathway inhibitor (hTFPI) and its inhibition effects on intimal proliferation in rabbit carotid arteries after balloon injury.
Rabbits underwent carotid artery balloon injuries were treated with Ad-TFPI (n = 25), Ad-LacZ (n = 25) or PBS (n = 10), respectively. Sham operated rabbits (n = 10) serve as normal controls. The expressions of human TFPI at mRNA and protein levels were detected by RT-PCR and ELISA respectively on the 3rd, 7th, 10th, 14th, 28th day after operation. Intimal proliferation was detected by angiograms and morphometric analysis.
TFPI mRNA and protein expressions were detected at 3 days and peaked at the 10th and 14th day after TFPI gene transfer. The expressions were still detectable on the 28th day. There was no TFPI expression in Ad-LacZ group. The carotid angiogram results indicated that the minimal lumen diameter in TFPI group was significantly larger and the lumina stenosis percentage was significantly lower in TFPI group compared those in Ad-LacZ and PBS groups (all P < 0.05). The morphometric analysis showed that the intimal area, the ratio of the intimal/media area, the lumina stenosis percentage in TFPI group were all significantly reduced compared with those in Ad-LacZ and PBS groups (all P < 0.01).
The TFPI gene could be effectively transferred by adenovirus vector to injured carotid arteries and transferred Ad-TFPI could significantly attenuate intimal proliferation in balloon injured carotid arteries in rabbits.
No preview · Article · Feb 2009 · Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases]