Biomedical Engineering and Bioengineering Commons^™

Development Of A Rotation Device For Microvascular Endothelial Cell Seeding, G. Pasquinelli, P. Preda, M. Vici, G. N. Martinelli, A. Freyrie, T. Curti, M. D'Addato

Cells and Materials

A rotation device (RD) specifically designed to achieve sterile endothelial cell (EC) seeding of vascular grafts has been developed. The basic characteristics of the RD include: small dimensions, fully autoclavable components, and perfectly sealed graft holders. These features make it possible to maintain sterility during all the steps of EC seeding. This was documented by negativity of all bacteriological assays performed . Moreover, the RD can simultaneously support three vascular grafts with different lengths (20, 40, and 60 cm) and diameters (4-8 mm). EC seeding is performed in the climatized chamber (37 °C; 5 % C02) with constant rotation (0.1 …

Apatite - Cholesterol Agglomerates In Human Atherosclerotic Lesions, Sara Sarig, Danielle Hirsch, Reuven Azoury, Teddy A. Weiss, Iony Katz, Howard S. Kruth

Cells and Materials

The purpose of this study was to examine the ultrastructural relationships of cholesterol crystals and apatite deposits in human atherosclerotic lesions. Segments of human aortic atherosclerotic lesions were obtained at autopsy , fixed in glutaraldehyde and dehydrated without using any organic solvents. The aortic segments were coated with carbon and subjected to various scanning electron microscope analyses. These included secondary electron imaging, back scattering of primary electrons, energy dispersive X-ray analysis of selected spots followed by area mapping of calcium and phosphorus , and cathodoluminescence.

The information gathered from scanning of selected areas in the lesions by all the techniques …

Evaluation Of The Images Of Specular Microscopy Of The Cells On Implanted Intraocular Lenses In Vivo, Kiyoshi Okada, Keiko Takahashi, Hiroaki Sagawa, Kuniomi Abe

Cells and Materials

Specular microscopy , an optical method to study the anterior segment of the eye, was applied to observe the cells on implanted intraocular lenses in vivo. The images from specular microscopy were evaluated by comparing the morphology of the same cells on intraocular lenses implanted in rabbit eyes by specular microscopy , light microscopy and scanning electron microscopy (SEM). The time lapse study in living human eyes and the optical evaluation of jts interference images were performed to elucidate its image formation.

The same giant cells, as observed in vivo by specular microscopy, proved to be multinucleated cells. It …

Polylysine Stimulation Of Ectopic Cartilage Formation, Rocky S. Tuan, Dina M. Turchi, David S. Kreitzer

Cells and Materials

Cartilage development, or chondrogenesis, is a process which involves the condensation of prechondrogenic mesenchymal cells, followed by the expression of the cartilage phenotype characterized by the biosynthesis of cartilage-specific, extracellular matrix components. We have previously shown that the cationic biopolymer, polylysine (PL), is able to stimulate chondrogenesis by embryonic limb bud mesenchymal cells in vitro. In this study, we have evaluated the chondrogenesis-stimulating activity of PL in vivo using an experimental system consisting of chick embryonic muscle explants, which were grafted onto the chorioallantoic membrane of chick embryos maintained in long-term shell-less culture. The muscle grafts were treated with PL …

Fracture Toughness And Fractography Of Dental Ceramics, H. J. Mueller

Cells and Materials

Chevron-notch short-rod fracture toughness (KIv) and scanning electron microscopy analyses of leucite-, tetrasilicic fluormica-, and alumina- reinforced dental ceramics and control materials were investigated. Short-rod fracture toughness is a measure of the bulk resistance to crack propagation but not of the surface resistance to crack initiation. Results indicated significant differences in KIv among the following six groups (from lowest to highest (a) Dicor and Optec, (b) Optec, Excelco's Incisal, Macor and Excelco's Gingival, (c) Excelco's Brush-O-Paque, (d) Vitadur-N core, (e) Coming's 9606 glass-ceramic, and (t) Vita Hi Ceram. Good agreement occurred with published data for Macor and 9606. Comparisons of …

The Articular Cartilage Of The Rabbit Knee: A Scanning Electron Microscopy Study, Daniel Levanon, Haim Stein

Cells and Materials

The surface morphology of eight sectors in the rabbit knee articular cartilage was studied using scanning electron microscopy. Cartilage surfaces showed wide variation in the shape, dimensions , and density of gaps and acellular processes. Patellas and load-bearing condyles revealed a relatively higher density of processes than did load-free condyles. Surface processes and gaps were abundant. They might represent a condensation product(s) of hyaluronic acid/protein complex that accrues during cycles of loading/weight bearing.