Biomaterial Database

Ultrastructural substrates of dystrophic calcification in porcine bioprosthetic valve failure. 1985

M Valente, and U Bortolotti, and G Thiene

Calcific degeneration is the main cause of porcine bioprosthetic valve failure. This dystrophic phenomenon has been studied by transmission electron microscopy in 26 explants; six normally processed unimplanted xenografts and a pig aortic valve from the slaughterhouse served as controls. Loss of endothelial lining and proteoglycans were a regular finding in all the commercially processed valves. In order to detect initial calcifications, we investigated in particular areas apparently devoid of mineralization at x-ray. Three main ultramicroscopic features were found: 1) intracytoplasmic and interstitial calcospherulae in 22 explants, 2) calcified collagen fibrils in 15, and 3) platelike calcium deposits upon amorphous material in 3. X-ray diffraction and energy-dispersive microanalysis identified Ca2+ deposits as crystals of hydroxyapatite. From these findings there is evidence that debris and membrane fragments of the pig cusp cells represent one of the initial nuclei of calcification.

UI	MeSH Term	Description	Entries
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D002114	Calcinosis	Pathologic deposition of calcium salts in tissues.	Calcification, Pathologic,Calcinosis, Tumoral,Microcalcification,Microcalcinosis,Pathologic Calcification,Calcinoses,Calcinoses, Tumoral,Microcalcifications,Microcalcinoses,Tumoral Calcinoses,Tumoral Calcinosis
D003094	Collagen	A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of SKIN; CONNECTIVE TISSUE; and the organic substance of bones (BONE AND BONES) and teeth (TOOTH).	Avicon,Avitene,Collagen Felt,Collagen Fleece,Collagenfleece,Collastat,Dermodress,Microfibril Collagen Hemostat,Pangen,Zyderm,alpha-Collagen,Collagen Hemostat, Microfibril,alpha Collagen
D006349	Heart Valve Diseases	Pathological conditions involving any of the various HEART VALVES and the associated structures (PAPILLARY MUSCLES and CHORDAE TENDINEAE).	Heart Valvular Disease,Valvular Heart Diseases,Disease, Heart Valvular,Heart Disease, Valvular,Heart Valve Disease,Heart Valvular Diseases,Valve Disease, Heart,Valvular Disease, Heart,Valvular Heart Disease
D006350	Heart Valve Prosthesis	A device that substitutes for a heart valve. It may be composed of biological material (BIOPROSTHESIS) and/or synthetic material.	Prosthesis, Heart Valve,Cardiac Valve Prosthesis,Cardiac Valve Prostheses,Heart Valve Prostheses,Prostheses, Cardiac Valve,Prostheses, Heart Valve,Prosthesis, Cardiac Valve,Valve Prostheses, Cardiac,Valve Prostheses, Heart,Valve Prosthesis, Cardiac,Valve Prosthesis, Heart
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001021	Aortic Valve	The valve between the left ventricle and the ascending aorta which prevents backflow into the left ventricle.	Aortic Valves,Valve, Aortic,Valves, Aortic
D001705	Bioprosthesis	Prosthesis, usually heart valve, composed of biological material and whose durability depends upon the stability of the material after pretreatment, rather than regeneration by host cell ingrowth. Durability is achieved 1, mechanically by the interposition of a cloth, usually polytetrafluoroethylene, between the host and the graft, and 2, chemically by stabilization of the tissue by intermolecular linking, usually with glutaraldehyde, after removal of antigenic components, or the use of reconstituted and restructured biopolymers.	Glutaraldehyde-Stabilized Grafts,Heterograft Bioprosthesis,Porcine Xenograft Bioprosthesis,Xenograft Bioprosthesis,Bioprostheses,Bioprostheses, Heterograft,Bioprostheses, Porcine Xenograft,Bioprostheses, Xenograft,Bioprosthesis, Heterograft,Bioprosthesis, Porcine Xenograft,Bioprosthesis, Xenograft,Glutaraldehyde Stabilized Grafts,Glutaraldehyde-Stabilized Graft,Graft, Glutaraldehyde-Stabilized,Grafts, Glutaraldehyde-Stabilized,Heterograft Bioprostheses,Porcine Xenograft Bioprostheses,Xenograft Bioprostheses,Xenograft Bioprostheses, Porcine,Xenograft Bioprosthesis, Porcine
D013552	Swine	Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).	Phacochoerus,Pigs,Suidae,Warthogs,Wart Hogs,Hog, Wart,Hogs, Wart,Wart Hog