AST-120, an Adsorbent of Uremic Toxins, Improves the Pathophysiology of Heart Failure in Conscious Dogs.

Purpose: Several lines of evidence suggest that renal dysfunction is associated with cardiovascular toxicity through the action of uremic toxins. The levels of those uremic toxins can be reportedly reduced by the spherical carbon adsorbent AST-120. Because heart failure (HF) causes renal dysfunction by low cardiac output and renal edema, the removal of uremic toxins could be cardioprotective.

Construction of 3 animal experimental models in the development of honeycomb microporous covered stents for the treatment of large wide-necked cerebral aneurysms.

The treatment of large or wide-necked cerebral aneurysms is extremely difficult, and carries a high risk of rupture, even when surgical or endovascular methods are available. We are developing novel honeycomb microporous covered stents for treating such aneurysms. In this study, 3 experimental animal models were designed and evaluated quantitatively before preclinical study.

Development of an in vivo tissue-engineered valved conduit (type S biovalve) using a slitted mold.

In autologous valved conduits (biovalves) using in-body tissue architecture, the limited area available for leaflet formation is a concern. In this study, we designed a novel biovalve mold with slits to enhance in vivo cell migration, regardless of size. As a control, the original mold without slits was used.

Successful implantation of autologous valved conduits with self-expanding stent (stent-biovalve) within the pulmonary artery in beagle dogs.

Objectives: To evaluate the functionality of an autologous heart valve with stent (Stent-biovalve or SBV) after implantation in the pulmonic valve position in beagle dogs.

Animals: Five beagle dogs.

Methods: A mold with an aperture of a tri-leaflet structure was constructed from a pair of concave and convex rods to which a nitinol (NiTi) stent was mounted.

Development of self-expanding valved stents with autologous tubular leaflet tissues for transcatheter valve implantation.

In this study, self-expanding valved stents were prepared by in-body tissue architecture technology. As molds, plastic rods (outer diameter; 14 or 25 mm), mounted with specially designed self-expanding stents, whose strut was a combination of two wavy rings and three pillars, were embedded into the subcutaneous pouches of goats or beagles for 1 month. Upon harvesting, the molds were fully encapsulated with membranous connective tissues, in which the stent strut was completely embedded.

In situ observation and enhancement of leaflet tissue formation in bioprosthetic "biovalve".

Biovalves, autologous tri-leaflet valved conduits, are formed in the subcutaneous spaces of animals. The valves are formed using molds encapsulated with autologous connective tissues. However, tissue migration into the small apertures in the molds for leaflet formation is generally slower than that for conduit formation around the molds.

Plasma atrial natriuretic peptide is an early diagnosis and disease severity marker of myxomatous mitral valve disease in dogs.

The aim of this study was to retrospectively assess the clinical usefulness of plasma atrial natriuretic peptide (ANP) concentrations for determining the severity of myxomatous mitral valve disease (MMVD) in dogs. Plasma ANP levels were found to be significantly higher in dogs with MMVD compared to healthy dogs, and plasma ANP levels increased significantly in dogs with progressive heart failure. In dogs with MMVD, stepwise regression analysis revealed that the left atrium/aorta ratio and fractional shortening could be used to predict the plasma ANP concentration.