The remodeling of cardiovascular bioprostheses under influence of stem cell homing signal pathways.

Optimizing current heart valve replacement strategies by creating living prostheses is a necessity to alleviate complications with current bioprosthetic devices such as calcification and degeneration. Regenerative medicine, mostly in vitro tissue engineering, is the forerunner of this optimization search, yet here we show the functionality of an in vivo alternative making use of 2 homing axes for stem cells. In rats we studied the signaling pathways of stem cells on implanted bioprosthetic tissue (photooxidized bovine pericardium (POP)), by gene and protein expression analysis.

Use of a Codman microsensor intracranial pressure probe: effects on near infrared spectroscopy measurements and cerebral hemodynamics in rats.

Intracranial pressure (ICP) monitoring is indispensable in the assessment of neurotrauma in humans and animal models. It was shown that cerebellar ICP, leaving the cortical area intact, can replace cerebral ICP in rats. While cerebral probes may induce spreading depression, the effects of a miniature cerebellar probe on near infrared spectroscopy (NIRS) measurements and cerebral hemodynamics are not known.

Functional and biomechanical evaluation of a completely recellularized stentless pulmonary bioprosthesis in sheep.

Objective: In a previous study we showed that recellularization of a stentless bioprosthetic valve is stimulated 1 month after implantation in the pulmonary position, when its matrix (acellular photo-oxidized bovine pericardium) was preseeded by intraperitoneal implantation during a 3-day period.

Methods: The present study reports on the functional and biomechanical properties of such valves (n = 19) in sheep up to 5 months after implantation. Similar valves (n = 20) that were not intraperitoneally preseeded served as controls.