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Location And Identification Of Colloidal Gold Particles On The Cell Surface With A Scanning Electron Microscope And Energy Dispersive Analyzer, Sinikka Eskelinen, Raija Peura

Scanning Microscopy

The use of colloidal gold particles for locating cell surface components by scanning electron microscopy (SEM) has been restricted due to difficulties in the identification of these gold particles under SEM. It is shown here how the gold particles bound to cell surfaces can be located and identified under SEM using the secondary electron imaging (SEI) mode with an energy dispersive X-ray microanalyzer (EDS). This enables reliable identification of gold particles and good quality micrographs of the cells to be achieved at the same time. The distribution of receptors for two lectins, concanaval in A (ConA) and wheat germ agglutinin …

Polarized Epithelial Cysts In Vitro: A Review Of Cell And Explant Culture Systems That Exhibit Epithelial Cyst Formation, J. A. Mcateer, G. S. Dougherty, K. D. Gardner Jr., A. P. Evan

Scanning Microscopy

The purpose of this paper is to review in vitro cell and explant culture systems that exhibit epithelial cyst formation and that are used as models of polarized epithelial function. We examine a number of culture systems derived from a variety of cell and organ types, briefly describe the methodology and conditions used to establish these cultures and discuss aspects of the experimental application of each system. We conclude that the characteristics of epithelial cyst-forming cultures are dependent upon the origin and identity of the cell population, as well as the multiple factors that define the culture environment. Culture systems …

The Role Of Scanning Electron Microscopy In Ophthalmic Science, P. Versura, M. C. Maltarello

Scanning Microscopy

The eyeglobe is one of the classical domains of Scanning Electron Microscopy (SEM) in biology as it exposes several inner and outer surfaces. Both corneal and conjunctival epithelia towards the tear film as well as the corneal endothelial cells facing the anterior chamber may be accurately evaluated. The architecture of the angle and particularly the morphology of the Schlemm's canal inner wall are clarified by SEM more than by TEM serial reconstruction. The surfaces of the iris and ciliary body, the zonula and the choroidal vessel arrangement are described in great detail. Three distinct types of membrane anchoring devices are …

Extracellular Matrix Production By Osteoblasts On Bioactive Substrata In Vitro, J. E. Davies, T. Matsuda

Scanning Microscopy

Some bone-substitute biomaterials have been classified as bioactive since they allow direct biological bonding to their surface in vivo. Using in vitro techniques, we have re-created the first stages of this biological bonding phenomenon and compared the initial, fibrillar, extracellular matrices produced by migrated primary osteoblast cell populations in contact with both dense and macroporous calcium phosphate substrata, apatite/bioactive glass composite (ABC) and 45S5 bioactive glass (BAG). The first formed fibrils in contact with these materials may be identified as collagen from their morphology as observed by scanning electron microscopy (SEM). However, the organization of this fibrillar material is …

Preparation Of Cytoskeletons Of Cells In Culture For High Resolution Scanning And Scanning Transmission Electron Microscopy, Paul B. Bell Jr., Margaretha Lindroth, Bengt-Arne Fredriksson

Scanning Microscopy

In this tutorial we describe our methods for preparing detergent-extracted cytoskeletons for observation by high resolution scanning (SEM) and scanning transmission (STEM) electron microscopy. We both discuss the theoretical background and provide practical procedures for each of the following steps: cell culture on Formvar-coated gold grids; prefixation with aldehydes or protein crosslinking reagents (homobifunctional N-hydroxy-succinimide esters); extraction with Triton X-100 or Brij 58 detergent in microtubule stabilizing buffer; postfixation in formaldehyde and glutaraldehyde; dehydration; critical point and freeze drying; sputter coating with 1-2 nm of platinum or tungsten; and examination by SEM and both normal and inverted contrast STEM. These …

Preparation Of Cultured And Isolated Cells For X-Ray Microanalysis, K. Zierold, D. Schäfer

Scanning Microscopy

Various electron microscopical preparation techniques are compared with regard to the preservation of the intracellular element distribution as determined by X-ray microanalysis in scanning and scanning transmission electron microscopy. By use of chemical agents for fixation and dehydration ions are redistributed and washed out. This is also true for freeze-substitution. Whole cells are prepared by cryofixation followed by freeze-drying. Interference of intracellular measurements by extracellular elements can be avoided by appropriate washing the cells before cryofixation. The washing medium has to be carefully selected in order to avoid distortions of the original intracellular element content. These problems are circumvented by …

Scanning Electron Microscope And Intragingival Microorganisms In Periodontal Diseases, F. R. Saglie

Scanning Microscopy

During the past two decades there has been an increased understanding of bacterial invasion as a pathogenic mechanism of periodontal diseases. Scanning Electron Microscope (SEM) has played a key role in supporting the idea that bacterial invasion may be another pathogenic mechanism in periodontal disease. This has been due to the fact that SEM has a larger depth of focus and better resolving power than the Light Microscope (LM) and also allows for observation of rather large areas of tissue showing in depth the surface of the sample.

This review deals with information obtained by using SEM as the fundamental …

Evidence Of Variable Zn/Fe In Zinc-Ferrites Produced From Roasting Of Zinc Sulphide Concentrate, R. Lastra, N. Rowlands, J. A. Finch

Scanning Microscopy

Zn-Fe-O phases formed during roasting of concentrates from zinc sulfide ores produce soluble zinc oxide, oxy-sulfates and insoluble ferrite compounds. The ferrites have a general formula ZnOFe₂O₃. However, these ferrites have a range of magnetic properties, suggesting variable stoichiometry. Scanning electron microscopy has been used to obtain the general relationship between the Zn/Fe ratio of the ferrites and their magnetic susceptibility.

Enamel Of Yalkaparidon Coheni: Representative Of A Distinctive Order Of Tertiary Zalambdodont Marsupials, K. S. Lester, M. Archer, C. F. Gilkeson, T. Rich

Scanning Microscopy

The enamel of an incisor and a premolar of Yalkaparidon coheni was examined by scanning electron microscopy in fractured and in sectioned, polished surfaces. The enamel of both teeth demonstrated: complete, ovoid and horse-shoe shaped prisms in a Pattern 2 arrangement; a simple parallel prism course; and, enamel tubules in abundance in the premolar but restricted to the innermost enamel in the incisor. Overall, the enamel ultrastructure supports the marsupial affiliation proposed for Yalkaparidon coheni but does not unambiguously ally it with any other order of marsupials.

The observation of a significant ultrastructural difference between the anterior and posterior teeth …

Pastoral Development Strategies In The Sahel And East Africa: Can The Mistakes Be Corrected?, Ahmed Musa Haji Ahmed

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

There is much controversy on the definition given to those people who raise livestock on the natural vegetation. Differences in the degree of their dependence on livestock and livestock products for food, as well as differences in the patterns of their movements, create the controversy. "Pure-pastoralists", "nomadic pastoralists", "semi - pastoralists", "semi-nomadic", "transhumant", and "semisedentary" are but some of the many terms used in the literature to describe them (see, for example, Johnson, 1969; Jacobs, 1965; McGee, 1986; Horowitz, 1981). To avoid much of the confusion created by the use of these terms, we use the definition of pastoralists as …

Cloning And Expression Of An Epstein-Barr Virus-Associated Dna Polymerase, Bruce D. Parker

Biology

Cells infected with Epstein-Barr virus (EBV) express a DNA polymerase that is distinguishable from the host DNA polymerases. The amino acid sequence encoded by the BALF5 open-reading frame (ORF) of the EBV genome was found to contain regions of strong similarity to the amino acid sequence of the herpes simplex (HSV-1) DNA polymerase. The putative amino acid sequence of BALF5 contains a potential 'leucine zipper' DNA binding domain. The BALF5 ORF was expressed in Escherichia coli using a pUC19 vector. The expressed DNA polymerase activity could be neutralized using EBV-specific antisera. The expressed protein had a size of approximately 108 …

Characterization Of Wolbachia Postica Which Causes Hybrid Incompatibility In Alfalfa Weevil, Sy-Jye Christine Leu

Biology

The rickettsia Wolbachia postica is the cause of hybrid incompatibility between males of the western alfalfa weevil and females of eastern or Egyptian weevils. Studies were carried out to obtain information about the biochemical and immunological characteristics of this microorganism. Because of the similarity between rickettsia and mycoplasma under the electron microscope, hybridization of DNA from this microorganism with a mycoplasma-specific gene probe confirmed a previous observation that this microorganism is a rickettsia. A rapid and accurate diagnostic assay for the infection of alfalfa weevils by wolbachia has been accomplished by the production of a polyclonal antibody against Wolbachia postica …

Effects Of Macrocyclic Trichothecene Mycotoxins On The Murine Immune System, Brian J. Hughes

Biology

The macrocyclic trichothecenes are a unique group of toxins which have some antileukemic properties. In the first study, verrucarin A and roridin A were examined. Both mycotoxins were administered intraperitoneally at an equitoxic dose of 0.35 mg/kg to CD-1 mice. Lymphocyte proliferation was studied on days 2, 4, and 7 after animals were dosed with verrucarin A. After day 2, no differences in ³HThymidine (³H-TdR) incorporation were observed using concanavalin A (Con A), phytohaemagglutinin (PHA), pokeweed mitogen (PWM), or lipopolysaccharide (LPS). On day 4, DNA synthesis induced by Con A, PHA, and PWM increased significantly. On day …

Biochemical Purification Of Nuclear Antigens And A Possible Autoimmune Reaction Against These Antigens In Autism, Mohamed Maroof Middib

Biology

Autism is a severe behaviorally defined disorder with a cause (or causes) that is still unknown. The objective of this study was to explore the possibility that autoreactivity against nuclear antigens is associated with this severe developmental disorder. Sera of autistic patients were tested for the presence of antibodies which were reactive with one or more of eight nuclear antigens including double-stranded deoxyribonucleic acid (DS-DNA), single-stranded deoxyribonucleic acid (SS-DNA), histone, deoxyribonucleoprotein (DNP), ribonucleoproteins Ro/SS-A and La/SS-B, RNP, and Smith's antigen (SM). Sera of autistic patients were found to be reactive with four of the nuclear antigens. These antigens included RNP, …

National List Of Plant Species That Occur In Wetlands: Intermountain (Region 8), Porter B. Reed, Jr., National Ecology Research Center

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

The National List of Plant Species That Occur in Wetlands represents the combined efforts of many biologists over the last decade to define the wetland flora of the United States. The U.S. Fish and Wildlife Service initially developed the list in order to provide an appendix to the Classification of Wetlands and Deepwater Habitats of the United States (FWS/OBS 79/31) to assist in the field identification of wetlands. Plant species that occur in wetlands, as used in the National List are defined as species that have demonstrated an ability to achieve maturity and reproduce in an environment where all or …

Intracellular Water Distribution And Aging As Examined By X-Ray Microanalysis, Thomas Von Zglinicki

Scanning Microscopy

The results reviewed here demonstrate that 1. the distribution of dry mass as observed in frozen-dried cryosections might be used as an unbiased measure of intracellular dry mass resp. water distributions in the tissue in vivo and 2. the well-known loss of water from cells during aging is solely due to a water loss from mitochondria without changes in the water content of all other components of the cell in the case of rat liver and heart muscle.

The reason for the water loss might be increased counter ion binding by membrane-bound enzymes due to decreased fluidity of the inner …

Elicitor Activity From The Ectomycorrhizal Fungus Rhizopogon Vinicolor, Margaret E. Coleman

Biology

Culture filtrate and mycelial surface components of the ectomycorrhizal fungus Rhizopogon vinicolor were partially purified by ion exchange and gel filtration chromatography and characterized. These Rhizopogon vinicolor components induced accumulations of condensed phenolics in treated conifer and benn calli and bean cotyledons. The treated issues became visibly brown relative to control tissues. The accumulation of phenolics in plant tissues suggests that certain components from the fungus possessed elicitor activity. Elicitor activity on treated been cotyledons was quantified by measurement of accumulations of low molecular weight and condensed phenolics. Data quantifying elicitor activity with intact conifer seedling roots and conifer calli …

An Experimental Analysis Of The Two-String Problem, Mary Ann Henneman

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The two-string problem (Maier, 1931) was used in an analysis of the contribution of experience in problem solving. In the two string problem subjects are shown two strings hanging from the ceiling and are instructed to tie the strings together. The strings are placed apart so that subjects are unable to grasp both strings simultaneously. The solution involves the use of items which are available in the vicinity of the strings. For example, a hammer can be used as a weight to make one string swing. The research comprised three separate experiments. The objective was to investigate environmental contributions, as …

Utah State University Commencement, 1988 – Main Campus, Utah State University

Commencement Programs

Ninety-Fifth Annual Commencement of Utah State University

Transverse Membrane Topography And Possible Precursors Of The B875 Light-Harvesting Polypeptides Of Wild-Type Rhodobacter Sphaeroides, Ron L. Peterson

Biology

The purpose of this work was to determine the membrane topography of the B875 light-harvesting complex of wild-type Rhodobacter sphaeroides and to determine if any precursors to the B875 polypeptides exist. To investigate the membrane topography of the B875 complex, I purified the B875 light-harvesting complex and membrane vesicles (chromatophores, and spheroplast-derived vesicles) from the intracellular photosynthetic membrane (ICM) of wild-type R. sphaeroides and treated each with proteinase K or trypsin. The B875-⍺ and -β polypeptides were analyzed by electrophoretic, and immunochemical methods. Proteinase K digested both polypeptides in the purified complex and completely eliminated the A875 spectral peak, characteristic …

The Distribution Of Utah Grasshopper Species (Order: Orthoptera) In Relation To The Distributions Of Community Types And Abiotic Factors, Catherine A. B. Gilbert

Biology

The practice of describing and mapping communities as community types assumes that all the organisms of a community have similar distributions. This assumption is counter to the hypothesis that organisms are distributed by their individualistic environmental tolerances and requirement (Gleason, 1926, 1939). Three major North American systems used to describe community-types are the biome (Clements and Shelford, 1939), the biotic area (Dice, 1943) and the life zone (sensu Holdridge, 1949). While these systems differ in the bases for community classification, they all use the distributions of 'key' species to predict the distributions of the remaining species in a community. …

Colonization Of Roots By Pseudomonas Putida And Its Role In Control Of Fusarium Wilt, Pouran Habibzadegah-Tari

Biology

Pseudomonas putida is a soil saprophyte that suppresses certain fungal root pathogens. The bacterium is an aggressive colonizer of plant root surfaces and the bacterial cells are agglutinated by a root surface glycoprotein, termed an agglutinin. To study the relationship between agglutination and root surface colonization, mutants of P. putida were derived which demonstrated enhanced or decreased agglutinability. In short-term binding studies, non-agglutinability. In short-term binding studies, non-agglutinable (Agg^-) mutants obtained by ethyl-methanesulfonate mutagenesis adhered to sterile bean seedling roots at levels 10-15 fold less than parental cells. Tn5-Agg^- mutants adhered at levels comparable to that of …

Gene Amplification And Cobalt Resistance In The Eukaryote Dictyostelium Discoideum, Hassan Ashktorab

Biology

The cob-354 cobalt resistance trait of the cellular slime mold Dictyostelium discoideum was shown to be associated with a DNA amplification. The amplified DNA was present in all cob-354 strains and absent from all cobalt sensitive strains. Cured strains, derived by passage of cob-354 strains in the absence of cobaltions, lost both the amplification and the cobalt resistance. The copy number of the amplified DNA was determined to be about 50 in cobalt resistant strain HU1628 by both Southern blot and slot blot analyses. Using transverse alternating field electrophoresis and a cloned portion of the amplification as probe, a band …

Morphometric Variation In Accipiter Hawks With Emphasis On Western North America, Jeff P. Smith

Biology

Measurements from more than 5,000 Sharp-shinned Hawks, Accipiter striatus, Cooper's Hawks, A. cooperii,, and Northern Goshawks, A. gentilis, trapped on the Goshute Mountains of eastern Nevada, were compiled. New species identification and sexing criteria were derived for accipiters in western North America. Goshute migrants averaged proportionately the longest wings and tails but weighed Jess than migrants from Marin Headlands, CA, Cedar Grove, WI, and Cape May Point, NJ. Interior migrants averaged less weight and longer wings and tails than coastal migrants. It is suggested that low flight-loading might be adaptive for migrating long distances, inhabiting open country, or …

The Effects Of Prey Vulnerability, Density, And Patch Replenishment In An Operant Analogue Of Foraging, Michael James Dewulf

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Foraging behavior has recently become a popular area of research with which ethologists, behavioral ecologists, and experimental psychologists converge their traditionally separate disciplines into a more multidisciplinary framework. Ethologists and behavioral ecologists usually study foraging as it occurs in the natural environment or the "field," while experimental psychologists contrive laboratory simulations of foraging and make the assumption, sometimes incorrectly, that generalization occurs across settings, situations, and species. Scientific advances are now beginning to occur in the ability of laboratory researchers to better simulate foraging as it occurs in the field. Field researchers are also becoming more willing to accept these …

Kinetics Of Two-Substrate Reactions Using Integrated Rate Equations, Leonard D. Holmes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The usual procedure employed in enzyme kinetic analysis is the method of initial rates. However, it has been appreciated for years that the analysis of enzyme-catalyzed reactions could, in principle, be more efficiently performed by examining the entire time course. There is much more information contained in a progress curve than in a simple initial rate. With the appearance of the computer, the formidable computations necessary for the use of integrated-rate equations are quite possible. The intention of this research was to develop the analytical and statistical methodology for applying an integrated-rate equation to a two-substrate reaction. I have analyzed …

Deer And Forestry In Germany: Half A Century After Aldo Leopold, Michael L. Wolfe, Friedrich-Christian V. Berg

Aspen Bibliography

No abstract provided.

Structure-Activity Relationships Of Retinoids In Developmental Toxicology, W. Brian Howard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The teratogenic potency of retinoid analogs was determined in Syrian hamsters and compared to the teratogenic potency of all-trans-retinoic acid (all-trans-RA, ED₅₀ = 10.5 mg/kg). A total of 15 analogs having variations in the cyclohexene ring were evaluated following various amounts of single oral doses on day 8 of gestation. Retinoids containing a five- or six-membered ring were as teratogenic as all-trans-RA, provided they had sufficient lipophilic substituents on the ring. The same pattern emerged for retinoids that had six-membered aromatic ring substitution for the natural cyclohexene ring of vitamin A. Incorporation of a supplementary …

Winter Ecological Energetics Of Blue Grouse, Peter Jeffrey Pekins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study investigated relationships between blue grouse (Dendragapus obscurus) winter habitat and blue grouse adaptive strategies and overwinter survival. Blue grouse metabolism, physical characteristics of use-trees and roost sites , microclimatic parameters at roost sites, daily winter energy costs, and specific energy-saving behaviors were studied. Blue grouse have a relatively low standard metabolic rate (SMR; 0.835 ml 0₂ · g^-1 · hr^-1) and lower critical temperature in comparison to other northern tetraonids . Metabolic rate did not significantly increase from -5 to -20 C. Ambient temperature (T_a) and the square root of …

Studies On Encephalomyocarditis Virus-Induced Diabetes In Mice, John Henry Huffman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The D-variant of encephalomyocarditis (EMC-D) virus was given to SJL/J mice by the artificial, intraperitoneal (ip) route of infection, or by the natural routes of infection per os (po) or intranasal (i.n.), in comparable concentrations. The po route of infection was found to be ineffective. Mice given virus by either the ip or i.n. routes of infection became diabetic. Mice were more resistant to the infectious and diabetogenic properties of the virus when given by the i.n. than when given by the ip route. Glycosuria in mice given virus i.n. usually lagged one day behind that in mice given virus …