BACKGROUND: The restenosis occurs up to 20%-30% following metal coronary stent implantation. Under the support of the 863 program, the feasibility to treat coronary artery stenosis using a novel drug-eluting stent (DES) has been investigated to reduce restenosis. OBJECTIVE: A drug-eluting stent (rapamycin as drug mode) was implanted into porcine models of coronary stenosis. The safety and efficacy of the drug-eluting stent were observed and compared with bare-metal stent. DESIGN, TIME AND SETTING: A randomized controlled animal experiment was performed in the Fu Wai Hospital for Cardiovascular Disease between November 2003 and April 2004. MATERIALS: A novel bioinspired phospholipid copolymer was synthesized by free radical polymerization of stearyl methacrylate, β-hydroxypropyl methacrylateand 3-(trimethoxysilyl) propylmethacrylate. METHODS: Twenty-one pigs were randomly divided into 3 groups: bare-mental stent, drug-eluting stent, and polymer-coated stent. The treated stents pre-loaded onto a delivery system through the use of crimping instrument were implanted into pig's coronary artery, with 2 stents per pig. MAIN OUTCOME MEASURES: Determination of luminal diameter, luminal area, mean intimal thickness on and between the stents, neointimal area, percentage of luminal area restenosis, and damage index using an image analysis instrument. RESULTS: At 28 days after implantation, there was significant difference in mean intimal thickness on and between the stents, as well as neointimal area, between the DES and bare-metal stent groups (P < 0.05). The neointimal area was reduced by 44.87% in the DES group compared with the bare-metal stent group. No significant difference in percentage of luminal area restenosis was found between the DES and bare-metal stent groups, but P value equaled to 0.053, which was close to 0.05. In addition, no restenosis was found in the DES group. CONCLUSION: Rapamycin DES can markedly resist intravascular intimal hyperplasia and restenosis following stenting.

Chromosomal mosaicism (CM) is a common phenomenon in preimplantation genetic testing (PGT). In embryos with CM, genetic contents of trophoblastic ectodermal (TE) cells may be different from that of the inner cell mass (ICM) which will develop into the fetus. Embryos with low mosaic proportion could give rise to healthy live births after transplantation, but are accompanied with high pregnancy risks such as high abortion rate. In order to provide a more comprehensive understanding for CM embryos, this article has systematically summarized the recent progress of research on the definition, mechanism, classification, PGT techniques, self-correction mechanism, transplantation outcome and treatment principles for CM embryos.
Pregnancy ; Female ; Humans ; Preimplantation Diagnosis/methods* ; Mosaicism ; Aneuploidy ; Genetic Testing/methods* ; Blastocyst

A novel bioinspired phospholipid copolymer has been synthesized by the radical polymerization of poly2-Methacryloyloxyethylphosphorylcholine (MPC), stearyl methacrylate (SMA), hydroxypropyl methacrylate (HPMA) and trimethoxysilylpropyl methacrylate (TSMA). Contact angle results indicated that the coating surface rearranged to get a more hydrophilic surface at the polymer/water interface. The membrane mimic phosphorylcholine coating surface could resist the platelet adhesion and prolong plasma recalcification time significantly. Rapamycin was used as model drugs to prepare drug-eluting coating. The animal experiments showed that this novel drug-eluting stent could effectively prevent the phenomena of restenosis.
Angioplasty, Balloon, Coronary ; instrumentation ; Animals ; Coated Materials, Biocompatible ; Coronary Restenosis ; prevention & control ; Drug-Eluting Stents ; Female ; Humans ; Male ; Materials Testing ; Methacrylates ; chemistry ; Phosphorylcholine ; analogs & derivatives ; chemistry ; Pilot Projects ; Polymers ; chemistry ; Prosthesis Design ; Random Allocation ; Sirolimus ; chemistry ; Swine ; Swine, Miniature