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Scanning Electron Microscopic Evaluation Of The Fractured Surfaces Of Canine Calculi From Substrata With Different Surface Free Energy, H. M. W. Uyen, W. L. Jongebloed, H. J. Busscher

Cells and Materials

The strength of adhesion between dental calculus and enamel or dentin surfaces determines the ease with which the calculus can be removed by brushing or professional dental treatment. In this study, we examined the adhesion of canine calculi formed on substrata with different surface free energies (sfe) and roughness by means of scanning electron microscopy. In 4 beagle dogs fenestrated crowns were made on the upper fourth premolars. Subsequently, facings of glass (sfe = 120 mJ. m-2), bovine enamel (sfe = 85 mJ.m-2), bovine dentin (sfe = 92 mJ.m-2), polymethyl-methacrylate (PMMA, sfe = 56 mJ.m-2) and polytetrafluorethylene (PTFE, sfe = …

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 …

Adhesion Of Staphylococci To Breast Prosthesis Biomaterials: An Electron Microscopic Evaluation, T. A. Fassel, J. E. Van Over, C. C. Hauser, C. E. Edmiston, J. R. Sanger

Cells and Materials

Gram-positive coagulase-negative staphylococci have been implicated in breast prosthesis infection. Staphylococcus au re us, Staphylococcus epidermidis, and Staphylococcus hominis strains were examined for adhesion and proliferation morphology to polyurethane foam and smooth silicone rubber prosthetic biomaterials. Ruthenium red, alcian blue and ruthenium red-lysine in en bloc procedures were applied to optimally visualize the polysaccharide slime. Ruthenium red processing resulted in observation of additional outer material close to the cell wall, more than seen in the absence of cationic reagent. Alcian blue preserved fibrous or netlike strands or meshworks of material. Ruthenium red-lysine preserved considerable amounts of slime covering the cocci …

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.

Preservation Of The Cell-Biomaterial Interface At The Ultrastructural Level, J. M. Schakenraad, J. A. Oosterbaan, E. H. Blaauw

Cells and Materials

Studying the tissue-biomaterial interface at the ultrastructural level is not without problems. Dissolution of the biomaterial in one of the dehydration or embedding media causes holes and shatter during sectioning or dislodgement of the biomaterial. The fine tuning of the hardness of both biomaterial and embedding medium, as well as the introduction of butyl-2,3- epoxypropylether as an intermediate between the dehydration series and the Epon resin , improving the impregnation , will solve many of the problems mentioned. With this improved technique good results were obtained with materials ranging from teflon, poly(Lactic acid) and polyurethanes to tissue culture polystyrene. No …

1990-1991 Annual Report, Various Authors

Annual Reports

No abstract provided.

Surface Modification Of Polymers To Permit Endothelial Cell Growth, C. James Kirkpatrick, Detlef Mueller-Schulte, Marc Roye, Guenter Hollweg, Claudia Gossen, Horst Richter, Christian Mittermayer

Cells and Materials

The interaction between endothelial cells (EC) and polymers has become relevant to medicine as a result of attempts to improve the biocompatibility of vascular prostheses. In man, endothelialization is minimal, so that vascular surgeons have attempted to pre-seed vascular grafts with autologous EC. The poor results of EC seeding of commonly used materials for vascular grafts, such as expanded polytetrafluoroethylene (ePTFE) or woven polyester (Dacron) has led to attempts to modify the surface of these and other polymers. Three principal modification techniques have been employed : 1. adsorption of bioactive molecules from applied solutions. Examples are fibronectin, collagen types I …

Wyoming Statewide Wilderness Study Report Wilderness Study Area Specific Recommendations, United States Bureau Of Land Management

All U.S. Government Documents (Utah Regional Depository)

The recommendation for this WSA is to designate 17,150 acres of BLM land and 1,390 acres of State land as wilderness. This alternative is considered to be the environmentally preferable alternative as it would result in the least change in the natural environment over the long term. The entire 17,150 acres of federal land and 1,390 acres of state land within the WSA are recommended for wilderness designation and are shown on the Bobcat Draw Badlands WSA map. The state lands would be recommended for acquisition to enhance the manageability of the area as wilderness.

Restoration And Expansion Of Bear River Migratory Bird Refuge, Brigham City, Utah, Environmental Assessment, U.S. Fish And Wildlife Service

Environmental Assessments (UT)

This Environmental Assessment is designed to evaluate possible actions for preserving and managing the wetland habitat on Bear River Migratory Bird Refuge (Refuge) and to consider additional wetlands for protection of environmental, wildlife, and recreational values.

Economic Impact Of Proposed Public Land Grazing Fee, Darwin Nielsen

Economic Research Institute Study Papers

No abstract provided.

Rural Utah Economic Survival -- Federal Land Grazing, Darwin Nielsen

Economic Research Institute Study Papers

No abstract provided.

Preservation And Immunogold Localization Of Lipids By Freeze-Substitution And Low Temperature Embedding, Wim Voorhout, Ida Van Genderen, Gerrit Van Meer, Hans Geuze

Scanning Microscopy

The success of postembedding immunocytochemistry depends largely on the preparation methods. The requirements for structural preservation and immunocytochemistry are in some cases contradictory. This is especially the case in the study of lipid-rich structures and the localization of lipid components. Earlier work on freeze-substitution has shown that this method is very promising for the preservation of lipids and the immunocytochemical localization of lipids at the electron microscopical level.

In this study we show that freeze-substitution in combination with low temperature embedding in Lowicryl HM20 has fulfilled this promise. Lamellar bodies in alveolar type II cells contain about 90% lipids and …

Reliability Of Intracellular Water And Ion Distributions As Measured By X-Ray Microanalysis - A Review, Thomas Von Zglinicki

Scanning Microscopy

X-ray microanalysis can be an important tool to reveal the spatial relationships between polyelectrolytes, ions, and water as they occur within cells and tissues in vivo. To reach this goal, at least two of these three closely interrelated variables should be measured independently. Moreover, the absence of systematic errors should be proven.

The present review discusses the probability of artificial ion and water shifts between intracellular compartments due to the growth of dendritic ice crystals much larger than the cross-sectioned remnants commonly seen in frozen-dried sections. Considering the possible mechanism of ice crystal growth it is concluded that ions and …

Cryopreparation Of Tissue For Clinical Applications Of X-Ray Microanalysis, Godfried M. Roomans

Scanning Microscopy

A number of diseases is associated with changes in ion and/or water distribution at the tissue or cell level, and X-ray microanalysis can be used to investigate the relationship between the disease process and the changes in elemental distribution. For analysis of diffusible elements by X-ray microanalysis, the tissue has to be prepared by cryotechniques. To carry out studies of this kind in a clinical environment poses a number of problems. Some of these problems occur already before the tissue is frozen, others are caused by the practical and ethical limitations that are imposed on the freezing method itself when …

Rainbow Bridge National Monument General Management Plan, Development Concept Plan, Resource Management Plan, Interpretive Prospectus, And Environmental Assessment, United States, Department Of The Interior, National Park Service

Resource Management Plans (UT)

This General Management Plan provides the National Park Service with direction for long-range management, development, and use of the Rainbow Bridge National Monument. The plan responds to new issues identified during the planning process when the draft plan was published in September of 1990. A main concern expressed during public review of the draft plan was diverse public expectations for visitor experience, crowding, and the high number of visitors accessing a limited area of Rainbow Bridge. In addition, the plan and environmental assessment address these diverse public expectations along with the issues of a visitor experience, protection of natural and …

Base Fee Adjustment Alternative, Darwin Nielsen

Economic Research Institute Study Papers

No abstract provided.

Public Lands Grazing Fees Important To Utah, Darwin Nielsen

Economic Research Institute Study Papers

No abstract provided.

The Market For Cull Cows: Ground Beef And Economic Development, Donald L. Snyder, Richard A. Wilde

Economic Research Institute Study Papers

No abstract provided.

Project Reports, Various Authors

Other Documents

No abstract provided.

Scanning Electron Microscopy Studies Of The Prevention Of Bioprosthetic Heart Valve Calcification With Controlled Release Polymeric Matrices, Yashwant V. Pathak, James Boyd, Thomas P. Johnston, Judith T. Levy, Gershon Golomb, Frederick J. Schoen, Robert J. Levy

Cells and Materials

Pathologic calcification is the principal failure mode of bioprosthetic heart valves fabricated from glutaraldehyde pretreated porcine aortic valves. Bovine pericardial bioprosthetic valves also fail frequently by calcification. This review covers the novel uses of the scanning electron microscope (SEM) for investigating the pathology and prevention of bioprosthetic heart valve calcification. The progression and growth of calcific lesions in the bioprosthetic heart valve tissues has been documented using SEM with elemental localization by energy dispersive X-ray analysis (EDX). Controlled release polymeric matrices consisting of either ethanehydroxydiphosphonate, FeC13 or Al(N0₃) 3 coimplanted with bioprosthetic tissue prevent experimental bioprosthetic calcification. SEM …

An Electron Microscopical Study Of The Interaction Of Bone With Growth Hormone Loaded Bone Cement, S. Downes, M. V. Kayser, G. Blunn, S. Y. Ali

Cells and Materials

Growth hormone was incorporated into Polymethylmethacrylate (PMMA) with a view to improving the quality of the bone-cement interface. Growth hormone was released from the PMMA and delivered to the cells at the bone-cement interface. The in vivo response to the growth hormone loaded cement was compared to the plain cement, using light microscopy, transmission electron microscopy and scanning electron microscopy, in a rabbit model. The results indicate that growth hormone released at the bone-cement interface stimulated osteogenesis and the reorganization of the tissue components. An advancing mineral front was observed in the direction of the bone cement with new bone …

Peripheral Nerve Regeneration Within Tubular Prosthesis: Effects Of Laminin And Collagen Matrices On Cellular Ingrowth, Ivar J. Kljavin, Roger D. Madison

Cells and Materials

Bridging a severed peripheral nerve with a tubular conduit, "entubulation repair" , allows manipulation of the microenvironment encountered by regenerating axons. In the present study, we placed the ends of severed mouse sciatic nerves into nonpermeable Tygon tubes to bridge a 4 mm nerve gap. The tube lumen was filled with either a collagen or laminin matrix. The matrices formed a stable 3-D structure connecting both proximal and distal stumps, and provided a scaffolding for the regenerating axons and their supporting cells. We examined with scanning electron microscopy (SEM), transmission electron microscopy (TEM) and light microscopy, the initial events of …

Ultrastructural Study Of Bone Formation On Synthetic Hydroxyapatite In Osteoblast Cultures, J. M. Sautier, J. R. Nefussi, N. Forest

Cells and Materials

Collagenase isolated rat calvaria cells forming a mineralized matrix in vitro were cultured in the presence of synthetic hydroxyapatite. Interactions between bone cells and hydroxyapatite biomaterial were followed by transmission electron microscopy. The appearance of a granular, collagen free, electron-dense layer at the periphery of the material was noted initially. Progressively, an amorphous, granular material formed and extended between the hydroxyapatite aggregates. Osteoblastic cells then synthesized an osteoid matrix which mineralized on the first formed granular collagen free layer, following a classical pattern of calcification . Demineralization of ultrathin sections confirmed the presence of this interface between the material and …

Interactions Of Bacteria And Amoebae With Ocular Biomaterials, Thomas John

Cells and Materials

The use of biomaterials in periocular and intraocular sites has resulted in some ocular inflammations and infections which can result in vision-threatening ocular disease. This review addresses bacterial interactions with, and adherence to ocular biomaterials such as soft contact lenses, surgical suture materials, and intraocular lenses. In addition, adherence of Acanthamoeba to soft contact lenses is described, and the role of these lenses in the development of Acanthamoeba keratitis is discussed.

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 …

Aldehyde Fixation Causes Membrane Vesiculation During Platelet Exocytosis: A Freeze-Substitution Study, E. Morgenstern

Scanning Microscopy

Despite a plethora of reports on the ultrastructure of secretory granule release by exocytosis, the release of coagulant activity from stimulated platelets is still being attributed to membrane vesiculation. Membrane vesiculation and the formation of myelin figures have been shown to be artifacts of glutaraldehyde GA fixation. Cells fixed by direct osmium or rapid freezing are free of such structures. Yet there is still doubt that rapid freezing interferes with vesiculation process. This study has addressed this issue by examining: (1) whether freezing and freeze-substitution affects membrane vesiculation, (2) whether paraformaldehyde-fixation also induces the phenomenon, and (3) whether the aldehyde …

Utah Science Vol. 52 No. 4, Winter 1991

Utah Science

128 A message to the Dairy Industry: Don’t Be Cowed by Surplus Milk

130 Cheesecake Lovers Take Heart

131 Super Sleuthing to Maintain Milk’s Purity

133 Letting milk Be Milk

134 Microbes Confer Healthful Benefits on Ice Cream and Yogurt

136 Improving the Mozzarella-Pizza Partnership

138 The Commerce of Good Ideas

139 Processing to Improve Yogurt

140 Cheesemaking: Simple Accidents Create a Complex Science

142 Developing Safer Food That Protects Itself

144 Sustainable Agriculture: A New Challenge for Land Grant Universities John E. Ikerd

150 Agricultural Research: A strategy for Success G.W. Bird

156 Trends in Chinese Agriculture Sylvan H. …

Predation Risk And The Importance Of Cover For Juvenile Rainbow Trout In Lentic Systems, R. A. Tabor, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Juvenile rainbow trout Oncorhynchus mykiss stocked in midelevation reservoirs in Utah inhabit shallow nearshore areas and are vulnerable to predation from piscivorous fish and birds. We determined the use and importance of nearshore habitats by (1) measuring habitat selection by, prey availability to, and feeding of juvenile rainbow trout in two reservoirs with populations of predators, and (2) measuring survival and growth rates in the presence and absence of cover in a pond experiment where adult brown trout Salmo trutta were predators. In the reservoirs juvenile rainbow trout (60–120 mm standard length) were abundant in complex inshore habitats but avoided …

High Voltage Electron Microscopy And Low Voltage Scanning Electron Microscopy Of Human Neoplastic Cell Culture, Marek Malecki

Scanning Microscopy

Improved procedures were developed to correlate cell culture data with the images provided by advanced ultrastructural technologies. These procedures were compatible with the two main types of cellular behavior: adherent, spreading (melanomas, rhabdomyosarcomas) and non-adherent in suspension (leukemias).

The ultrastructure and function of spreading neoplastic cells primarily depend on surface properties of the attaching substrates. Therefore, the films used for cultured cell whole-mount ultrastructural analysis must have adherence features identical to those of standard cell culture vessels. Improved procedures were developed to produce the polystyrene films of required qualities. These films allowed processing of cells for electron microscopy including chemical …

Structures And Properties Of Stabilized Vitamin And Carotenoid Dry Powders, Victor E. Colombo, Francoise Gerber

Food Structure

The development of special formulated forms of vitamin and carotenoid dry powders solved most of the technical problems encountered in handling the original pure crystalline or oily compounds. Various procedures to obtain stabilized products have been introduced on an industrial scale for feed , food and pharmaceutical purposes. Proven modes of manufacture of formulated dry powders includes the numerous spraying processes for emulsions, dispersions or solutions, and the production of adsorbates of fat-based products.

The objective of this paper is to provide an overview of stabilized vitamin and carotenoid dry powders. This contribution is intended to demonstrate the usefulness of …