Low molecular weight heparin microcapsule coated occluder for atrial-septal defects / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSIONS</b>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.</p>

Comparison of characteristics of SVCV strains isolated in China and in Europe / 病毒学报

In the nationwide epidemiological investigation, SVCV-741 was for the first time isolated in Beijing region, China in 2003, and designated as SVCV Asian strain. In this paper, we compared SVCV-741 (Asian strains isolated in China) with SVCV-10/3 (Europe reference strain) on their physico-chemical, biological and morphological characteristics. The results indicated that there were no distinct differences between two SVCV strains on phycico-chemical and morphological characteristics. The main existing differences were: (1) The stability of SVCV-741 to temperature in cell culture was higher than that of SVCV-10/3, which might have some evolutionary and biological implication of SVCV; (2) No SVC outbreak ever occurred caused by SVCV-741;Furthermore we found that both SVCV-741 and SVCV-10/3 grew faster and produced higher virus titer in CO cells than other cell lines. It indicated that CO cell lines might be useful tool for SVCV research.