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Structural characterization of a series of novel bio-polyamides based on renewable raw materials-PA 4.10, PA 6.10, PA 10.10, and PA 10.12-was performed by Fourier transform infrared spectroscopy (FTIR) and wideangle X-ray diffraction (WAXD). Infrared spectra and the WAXD patterns indicate the coexistence of different crystalline forms, a-and c-triclinic and b-pseudohexagonal. Thermal properties in the glass transition (T g ) and melting region were then investigated using temperaturemodulated DSC (TOPEM Ò DSC). The melting point (T m ) was found to increase with increasing amide/methylene ratio in the polymer backbone, which is consistent with the increase in linear density of hydrogen bonds. Studies on the molecular dynamics by dynamic mechanical analysis show three distinct regions associated with the c-and the b-relaxation and the dynamic glass transition. TOPEM Ò DSC data reveal that at low frequency/long timescales, the materials with significantly different amide/methylene ratios have similar segmental dynamics.

Objective-We compared the antithrombotic effects in vivo of 2 chemically different carbon monoxide-releasing molecules (CORM-A1 and CORM-3) on arterial and venous thrombus formation and on hemostatic parameters such as platelet activation, coagulation, and fibrinolysis. The hypotensive response to CORMs and their effects on whole blood gas analysis and blood cell count were also examined. Methods and Results-CORM-A1 (10-30 µmol/kg, i.v.), in a dose-dependent fashion, significantly decreased weight of electrically induced thrombus in rats, whereas CORM-3 inhibited thrombosis only at the highest dose used (30 µmol/kg). CORM-A1 showed a direct and stronger inhibition of platelet aggregation than CORM-3 in healthy rats, both in vitro and in vivo. The antiaggregatory effect of CORM-A1, but not CORM-3, correlated positively with weight of the thrombus. Concentration of active plasminogen activator inhibitor-1 in plasma also decreased in response to CORM-A1, but not to CORM-3. Neither CORM-A1 nor CORM-3 had an effect on plasma concentration of active tissue plasminogen activator. CORM-3, but not CORM-A1, decreased the concentration of fibrinogen, fibrin generation, and prolonged prothrombin time. Similarly, laser-induced venous thrombosis observed intravitally via confocal system in green fluorescent protein mice was significantly decreased by CORMs. Although both CORM-A1 and CORM-3 (30 µmol/kg) decreased platelets accumulation in thrombus, only CORM-A1 (3-30 µmol/kg) inhibited platelet activation to phosphatidylserine on their surface. Conclusion-CORM-3 and CORM-A1 inhibited thrombosis in vivo, however CORM-A1, which slowly releases carbon monoxide, and displayed a relatively weak hypotensive effect had a more pronounced antithrombotic effect associated with a stronger inhibition of platelet aggregation associated with a decrease in active plasminogen activator inhibitor-1 concentration. In contrast, the fast CO releaser CORM-3 that displayed a more pronounced hypotensive effect inhibited thrombosis primarily through a decrease in fibrin generation, but had no direct influence on platelet aggregation and fibrynolysis. (Arterioscler Thromb Vasc Biol. 2012;32:2149-2157.)Key Words: carbon monoxide ◼ carbon monoxide-releasing molecules ◼ fibrin generation ◼ green fluorescent protein mice ◼ intravital microscopy ◼ plasminogen activator inhibitor-1 ◼ platelet aggregation ◼ rat ◼ thrombosis