The microstructure of collagen type I gel cross-linked with gold nanoparticles.

Scanning electron microscopy, transmission electron microscopy, rheometry, and electrochemistry were used to provide insight into the microstructure of collagen type I gel (1%, w/v) modified with the tiopronin-protected (N-(2-mercaptopropionyl)glycine) gold nanoparticles (TPAu), a multivalent crosslinker. The cross-linking reaction, performed via EDC (1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide) coupling, results in compliant, mechanically stable and continuous gels. The gels contain unusual interconnected collagen-TPAu particles.

Use of contrast echocardiography to detect displacement of the needle during pericardiocentesis.

Bedside pericardiocentesis is a safe and routinely practiced procedure. We report a case in which echocardiography-guided pericardiocentesis was performed urgently for cardiac tamponade. In this case, there was displacement of the periocardiocentesis needle that was only detected by change in the color of aspirated fluid and confirmed by the use of contrast echocardiography.