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Characterization Of Chemical And Radiation-Induced Dna Damage In The Mdbk Cell Culture System, Jeffrey R. Hincks

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A mechanism common to many carcinogens and mutagens is the interaction with cellular DNA. Alkaline elution is a sensitive and commonly used technique to detect cellular DNA damage in the form of DNA single-strand breaks (SSB), DNA-protein cross-links (DPC), and DNA interstrand cross-links (ISC). In the present study, gravity-flow alkaline elution was developed and validated to rapidly detect DNA damage in the MDBK cell culture system by genotoxic agents.

The system was first validated by detecting a dose dependent induction of DNA SSB in cells exposed to 25-1500 rad of X-ray. The assay reliably detected the DNA damage of seven …

Surface And Sub-Surface Composition And Properties Of Ion-Bombarded Lithium Alloys, A. R. Krauss, D. M. Gruen, N. Q. Lam, A. B. Dewald, M. G. Valentine, A. Sagara, K. Kamada

Scanning Microscopy

Lithium-bearing alloys such as Si-Li, Al-Li and Cu-Li are of importance in a variety of technological applications, many of them depending on the fact that the surface composition of these alloys differs significantly from that of the bulk, both at thermal equilibrium and under ion bombardment. During ion sputtering, these materials exhibit a variety of phenomena which affect the surface composition and concentration depth profile in a complex manner. We present here experimental measurements of the surface and near-surface composition profiles of sputtered Cu-Li and Al-Li alloys. The experimental results are interpreted in terms of surface loss and radiation-induced segregation …

Multiphoton Ionization Followed By Time-Of-Flight Mass Spectroscopy Of Sputtered Neutrals, M. J. Pellin, C. E. Young, D. M. Gruen

Scanning Microscopy

Multiphoton ionization (MPI) by pulsed, tunable lasers provides a sensitive means for detection of neutral atoms, resulting from the high probability achievable in both the ionization and subsequent detection steps. Substantial selectivity is achieved by excitation between energy levels of the atom of interest. This resonant MPI technique can access all atomic states including ground and metastable levels.

The high efficiency of MPI technique permits detailed sputtering data to be obtained with minimal target damage. The goal is to obtain velocity and angular distributions for each energy level of every sputtered species. In practice, two types of experimental configurations have …

A New Method For Finishing Minicavities, A. Lussi, M Gygax, P. Hotz, D. Lüthi

Scanning Microscopy

Minicavities were prepared in 26 caries-free teeth. Cavity preparation and the finishing of the occlusal area and the gingival floor was done with diamond burs (diameter 1 mm, grain sizes 90 μm and 15 μm, respectively). For the finishing of the axial box margin and the proximo-cervicaI curved border, a new set was developed: It is composed of an EVA-system with the total amplitude reduced to 0.34 mm, and a highly flexible file (Cavishape, grain 15 μm). The shape of this file had to be modified in order to follow the proximo-cervical curvature. The efficiency of the new device was …

Proton Microprobe And Particle Induced X-Ray Emission (Pixe) Analysis For Studies Of Pathological Brain Tissue, K. G. Malmqvist, A. Brun, K. Inamura, E. Martins, L. G. Salford, B. K. Siesjö, U. A. S. Tapper, K. Themner

Scanning Microscopy

Particle Indiced X-ray Emission and proton microprobe analyses have been applied for the investigation of regional elemental distributions in connection with various pathological states in the brain. Malignant brain tumours and adjacent histologically intact tissue removed during surgery were analysed with PIXE. Systematic elemental variations, e.g., for calcium and selenium, were observed in the tumour front. The proton microprobe was applied to study the Ca and K concentrations in various cell strata in hippocampus following transient ischaemia in rat brain. Significant increases in the Ca level occurred in selectively vulnerable cells within 48 h after the ischaemia.

The Growth Of Calcium And Strontium Sulfates On Barium Sulfate Surfaces, L. Perez, G. H. Nancollas

Scanning Microscopy

The crystallization of calcium sulfate dihydrate (gypsum) and strontium sulfate (celestite) induced by the presence of barium sulfate (barite) surfaces has been studied using a Constant Composition kinetic method. In contrast to calcium sulfate, strontium sulfate appears to grow epitaxially on barium sulfate surfaces. However, barium sulfate induces calcium sulfate dihydrate precipitation from meta stable supersaturated solutions of the salt. Following nucleation, the rate of growth of strontium sulfate was found to be a second order with respect to supersaturation indicating a surface dislocation growth mechanism. The observed epitaxial growth is in agreement with calculations based on crystal lattice mismatch.

Zinc Deficiency: Specific Scalp Hair Defects Seen By Scanning Electron Microscopy May Provide A Valuable New Test, D. W. Gregory, L. Stankler

Scanning Microscopy

Zinc deficiency in man results in multisystem disease. It may be acquired or hereditary; the latter can be fatal if left untreated. Premature babies are particularly susceptible to zinc deficiency. Unfortunately no simple, reliable test for zinc status exists at present.

Short, newly-emerging scalp hair samples from 3 classical cases of zinc deficiency all showed the same characteristic abnormalities when examined by scanning electron microscopy, i.e. straight, blunt tips bearing scales, unusually thick cuticular scales with jagged free-edges, and very fine longitudinal corrugations in individual scales. These abnormal features occurring together appear to be specific for zinc deficiency; they also …

Insites, Spring 1988, Utah State University

inSites

Magazine of the Department of Landscape Architecture and Environmental Planning

Utah Science Vol. 49 No. 1, Spring 1988

Utah Science

2 THE BLUE ORCHARD BEE: AN ALTERNATIVE POLLINATOR OF APPLES P. Torchio The blue orchard bee could be the answer to a threatened honeybee shortage.

10 BEATING THE ODDS-IDENTICAL TWINS FOR CA TILE RESEARCH C. W. Arave, T. D. Bunch, C. H. Mickelsen and D. Purcell Methods of splitting embryos to obtain more identical twin calves will facilitate research and may eventually lead to techniques to clone embryos on a commercial scale.

17 IRON DEFICIENCY IN PLANTS: GENOTYPIC MODIFICATION OF SOIL FERTILITY J. H. Bennett, N. J. Chatterton, P. A. Harrison and W. R. Thornely A review of recent research …

Scanning Electron Microscopy Of The Spermatheca Of Plethodon Larselli (Amphibia: Plethodontidae): Changes In The Surface Morphology Of The Spermathecal Tubule Prior To Ovulation, Christine M. Davitt, John H. Larsen Jr.

Scanning Microscopy

Spermathecae from eight mature female Larch Mountain salamanders (Plethodon larselli) were used to study cellular changes accompanying the administration of ovulation-inducing pregnant mare serum gonadotropin (PMSG). Animals injected daily with 25 IU of PMSG were sacrificed on day 2 or day 4. Ultrastructural alterations of the spermathecal tubules include an increase in the synthesis and release of product into the lumen and hypertrophy of two epithelial cell types by day 4. One cell type exhibits apocrine blebs and is covered with microvilli; the other contains large spherical vesicles and has only a few, short microvilli on its surface. These changes …

Developmental And Radiobiologic Characteristics Of Canine Multinucleated, Osteoclast-Like Cells Generated In Vitro From Canine Bone Marrow, T. M. Seed, L. V. Kaspar, F. Domann, G. K. Niiro, D. A. Lebuis

Scanning Microscopy

We report here our initial observations on the growth and morphology, and developmental radiosensitivity of giant, multinucleated, osteoclast-like cells (MN-OS} generated through in vitro cultivation of hematopoietic progenitor-enriched canine bone marrow samples. Maximum cell densities of 5.5 x 10³ to 6.5 x 10³ MN-OS per cm² of growth area were achieved following 10 to 14 days of culture at 37°C. Acute gamma irradiation of the initial marrow inocula resulted in significant, dose-dependent perturbations of MN-OS formation, growth, and development. Attempts to estimate radiosensitivity of MN-OS progenitors from canine marrow yielded a range of D_O values from …

Sem Of Canine Chromosomes: Normal Structure And The Effects Of Whole-Body Irradiation, G. K. Niiro, T. M. Seed

Scanning Microscopy

Canine chromosomes are not only numerous (38 autosomal pairs), but they are small (compared to human chromosomes) and morphologically similar as well. Analysis of the canine karyotype by light microscopy (LM) of banded chromosomes is, thus, difficult, and the literature on the canine karyotype is scanty. In this study, we describe examination of chromosomes from normal and chronically irradiated dogs with the scanning elect ran microscope (SEM). Metaphase chromosomes from bone marrow aspirates were Giemsa-banded with either 0.025% trypsin alone or 0.1% trypsin preceded by 10% H2O2 and prepared for SEM. Examination of chromosomes from normal dogs revealed cylindrical chromosome …

Silver As A Removable Conductive Coating For Scanning Electron Microscopy, A. A. Mills

Scanning Microscopy

A thin film of silver, applied by sputtering or vacuum evaporation, provides an excellent conformal conductive coating for scanning electron microscopy of insulating specimens. When no longer required it is easily removed with Farmer's reducer a dilute aqueous solution of potassium ferricyanide and sodium thiosulphate. No damage was apparent to fine structure in the calcite matrix of ostracode shells, or to other biological tissues. No problems have been encountered with grain in the silver film at magnifications up to 15,000 X, or in the storage of coated specimens in a desiccator for periods exceeding 6 months.

Enamel Structure In Primates: A Review Of Scanning Electron Microscope Studies, L. B. Martin, A. Boyde, F. E. Grine

Scanning Microscopy

Comparative studies of dental enamel microstructure have involved three main areas of enquiry, with structural features having been investigated in relation to developmental mechanisms, function and/or phylogeny. The phylogenetic, or taxonomic aspect has been emphasized in the majority of studies involving the Order Primates, where efforts have focused upon attempts to recognise structural differences among various hierarchical groups.

Studies of primate enamel microstructure by SEM are reviewed here, with emphasis on what has been learned concerning the most suitable preparative techniques that can be employed, and with particular emphasis to the relevance of enamel microstructure in taxonomic analyses of living …

The Capabilities Of The Microprobe Kontron Image Analysis System: Application To Mineral Beneficiation, W. Petruk

Scanning Microscopy

Image analysis is a technique for determining quantities, grain size distributions, grain orientations, intergrowths, associations, liberations and degrees of alteration of minerals or phases in naturally occurring and processed materials. It is performed by analysing images of polished or thin sections of the material under study. To obtain accurate results the images must be faithful reproductions of the material, and each mineral or phase displayed in the images must be distinct enough to be automatically discriminated and identified without operator interaction. An image analysis system that meets these requirements was developed in the Process Mineralogy Section at CANMET by interfacing …

The Effects Of Polepiece Saturation On The Electron Optical Properties Of Asymmetric Condenser - Objective Lenses, Wenxiong Chen

Scanning Microscopy

The electron optical properties of an asymmetric magnetic condenser-objective lens are determined not only by its geometric structure and shape parameters, but also by the degree of saturation of its polepieces. A systematic investigation has been carried out for a series of asymmetric magnetic condenser-objective lenses. Results show that, owing to its small bore, the lower polepiece of such an asymmetric condenser-objective lens has considerable effects on the electron optical properties. When this polepiece is appropriately highly saturated, an asymmetric condenser-objective lens possesses low spherical aberration and chromatic aberration coefficients. On the other hand, the large bore of the upper …

Microscopic Effects Of Predator Digestion On The Surfaces Of Bones And Teeth, John M. Rensberger, Hartmut B. Krentz

Scanning Microscopy

Concentrations of small fossil mammals are frequently encountered in Cenozoic deposits, but the causes for such accumulations have seldom been determined. In many cases the tooth, jaw, and limb fragments appear to be well-preserved under light microscopy, and it is difficult to differentiate damage due to predator digestion from breakage and abrasion due to physical agents. In order to find more specific evidence of predator digestion, we used a scanning electron microscope (SEM) to examine the surface microstructure of bones and teeth consumed by Bubo virginianus (great horned owl) and Canis latrans (coyote), which prey upon similar species. Effects …

Biomedical Applications Of Proton Induced X-Ray Emission, R. D. Vis

Scanning Microscopy

Apart from studies on aerosols, the majority of applications of proton induced X-ray emission (PIXE) with a normal beam or a microprobe (micro-PIXE) is found in biology and medicine. Two aspects of broad beam PIXE are often decisive for the choice of this analytical technique. Compared to other techniques capable of analysis down beyond the ppm level, PIXE can be carried out with a very small amount of material and minute fractions of the composite samples, even in the scale of micrometers and quite often with minimal sample preparation, which are important requirements for biomedical investigations. Secondly, the speed of …

A Physical Theory Of The Living State: Application To Water And Solute Distribution, G. N. Ling

Scanning Microscopy

This review begins with a summary of the disproof of the membrane-pump theory and the alternative theory of the living cell, the association-induction (AI) hypothesis. Being alive in the AI hypothesis represents the maintenance of a high (negative) energy-low entropy state in which the two major components K⁺ and water of the living cell are closely associated with the third major component of the living cells, proteins. K⁺ is adsorbed singly on 𝜷-and γ-carboxyl groups and the bulk of cell water in multilayers on the exposed NHCO groups of fully extended polypeptide chains of cell proteins. These adsorptions …

Solute Exclusion By Polymer And Protein-Dominated Water: Correlation With Results Of Nuclear Magnetic Resonance (Nmr) And Calorimetric Studies And Their Significance For The Understanding Of The Physical State Of Water In Living Cells, G. N. Ling

Scanning Microscopy

According to the polarized multilayer (PM) theory of cell water proteins with their back-bones fully extended and their NHCO groups directly exposed to bulk water, polarize water in multilayers. Experimental testing of the theory led to a new understanding of the uniqueness of gelatin, due to its permanently maintained fully extended conformation and its ability to polarize the bulk phase water in multilayers with reduced solubilities for solutes in a size dependent manner ("size rule"). Other models which behave like gelatin are urea-denatured proteins, synthetic polymers like polyethylene oxide (PEO), and polyvinylpyrrolidine (PVP), but not native proteins. NMR studies showed …

Scanning Electron Microscope Diagnosis Of Wear Patterns Versus Artifacts On Fossil Teeth, Mark F. Teaford

Scanning Microscopy

Recent work with modern mammalian teeth has shown that, during an animal's lifetime, microscopic wear patterns are generally laid down in a regular fashion at specific locations on the teeth. These regularities make it possible to distinguish real dental microwear (resulting from behaviors during life) from artifacts of preservation and preparation (postmortem wear) on fossil teeth. The size, shape, location, and orientation of microscopic wear features can all aid in making such distinctions.

Several types of postmortem wear are identifiable on fossil teeth. Since some of these effects are intimately tied to the taphonomic history of the fossil, some postmortem …

Structure And Function Of Connective Tissue In Cardiac Muscle: Collagen Types I And Iii In Endomysial Struts And Pericellular Fibers, Thomas F. Robinson, Leona Cohen-Gould, Stephen M. Factor, Mahboubeh Eghbali, Olga O. Blumenfeld

Scanning Microscopy

Heart myocytes and capillaries are enmeshed in a complex array of connective tissue structures arranged in several levels of organization: epimysium, the sheath of connective tissue that surrounds muscles; perimysium, which is associated with groups of cells; and endomysium, which surrounds and interconnects individual cells. The present paper is a review of work in this field with an emphasis on new, unpublished findings, including composition of endomysial fibers and disposition of newly described perimysial fibers. The role of scanning electron microscopy in the development of current understanding is also outlined. Biaxially arranged epimysial fibers form a sheath around papillary muscles …

Bioapplication Of Colloidal Gold In Microbiological Immunocytochemistry, Julian E. Beesley

Scanning Microscopy

Microbiological organisms are an ubiquitous group of animals encompassing bacteria, viruses, protozoa, algae and fungi. They are adapted for survival in many diverse habitats and exert a profound effect on man and his environment. Colloidal gold electron immunocytochemistry is a useful technique for studying these organisms and may be applied in several ways. The post-embedding technique is used to detect internal antigens, whilst the pre-embedding technique is employed for the detection of external antigens. In contrast the immuno-negative stain technique is applied to detect antigens on structures such as viruses or bacterial pili which may be dried down onto an …

Metal Ion And Cluster Beams For Microelectronic Research And Development: A Review, G. Ben Assayag, P. Sudraud

Scanning Microscopy

Applications of focused ion and cluster beams emitted by liquid metal ion sources are particularly attractive in microelectronic engineering. We overview this area of research and development adding recent results concerning repair, tuning and characterization obtained either by focusing ions or droplets on a microcircuit controlled by in-situ SEM observation of the process.

Calcium Pyrophosphate Crystal Deposition: The Effect Of Monosodium Urate And Apatite Crystals In A Kinetic Study Using A Gelatin Matrix Model, Gretchen S. Mandel, Paul B. Halverson, Neil S. Mandel

Scanning Microscopy

The kinetics of calcium pyrophosphate dihydrate (CPPD) crystal growth was studied by allowing calcium and pyrophosphate (PPi^-4) ions to diffuse through a denatured collagen matrix (biological grade gelatin) in the presence of either monosodium urate monohydrate (MSU) or hydroxyapatite (HA) crystals. In this in vitro model system, MSU crystals significantly altered the kinetics of PPi^-4 ionic diffusion through the gelatin matrix by allowing the [PPi^-4] gradient to fall off much more rapidly, suggesting an increased level of scavenging of PPi^-4 ions into crystalline materials. Even more significantly, the presence of MSU crystals markedly influenced the …

Calcium Pyrophosphate Crystal Deposition: The Effect Of Soluble Iron In A Kinetic Study Using A Gelatin Matrix Model, Gretchen S. Mandel, Paul B. Halverson, Neil S. Mandel

Scanning Microscopy

The kinetics of calcium pyrophosphate dihydrate (CPPD) crystal growth was studied by allowing calcium and pyrophosphate (PPi^-4) ions to diffuse through a denatured collagen matrix (biological grade gelatin) in the presence of either ferric or ferrous ions. Ferric and, to some extent, ferrous ions blocked the migration of the PPi^-4 diffusion gradient. This retardation in the [PPi^-4] gradient led to numerous changes in the patterns of CPPD crystal formation. At the initial stages of crystal growth, the iron ions induced more crystal growth compared to control. At later incubation times, ferrous and ferric ions enhanced …

Assessments Of Pulmonary Macrophage Clearance Responses To Inhaled Particulates, David B. Warheit, Mark A. Hartsky

Scanning Microscopy

An integrated bioassay program is being developed to evaluate the toxicity of inhaled particulate materials. The multi-disciplined approach combines studies on lung clearance mechanisms with pulmonary macrophage functional assessments based on cellular biology, biochemical and cytochemical evaluations on lung specimens from exposed animals. To validate this method, animals were exposed to asbestos, iron-treated asbestos, fiberglass, Mt. St. Helens ash or carbonyl iron particles. Deposition patterns, macrophage migration and phagocytosis were monitored in vivo at selected time periods after exposure. Our results showed that chemotactic factor generation by particles in vitro correlated with the corresponding macrophage recruitment responses in vivo. …

Clinical Applications Of Scanning Electron Microscopy And Energy Dispersive X-Ray Analysis In Dermatology - An Up-Date, Bo Forslind

Scanning Microscopy

Dermatological papers comprising scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis data published 1983 through 1986 in international journals are reviewed, as an update to our 1984 paper on Clinical applications of scanning electron microscopy and X-ray microanalysis in dermatology. The present paper not only deals with a review of recent publications in this area but also presents the application of microincineration to hair and cryosectioned freeze-dried skin specimens. Examples of the increased contrast obtained in hair cross sections are presented and a discussion on the feasibility of microincineration at analysis of hair and skin cross sections is …

Three Dimensional Secondary Ion Mass Spectrometry, J. D. Brown

Scanning Microscopy

The determination of the three dimensional distributions of impurities and dopants at low concentrations in solid materials is possible using either ion probes or ion microscopes. The potential depth resolution in such determinations is of the order of 1 nm while the lateral resolution is limited to about 10-100 nm by collision processes. Ion microprobes are approaching these limits while ion microscope lateral resolution is currently ~ 0.5 μm. Ion microprobes have the advantage of a relatively simple ion detection and image formation system but at the expense of speed of data accumulation. Ion microscopes accumulate image information simultaneously over …

The Dento-Gingival Junction As Seen With Light Microscopy And Scanning Electron Microscopy, J. J. Garnick, R. D. Ringle

Scanning Microscopy

The purpose of this paper is to review the anatomical relationship of the Dento-Gingival Junction as seen in the human dentition. The junction is described under light microscopy and then reviewed as seen in the SEM with the authors' unpublished findings. The authors' material was derived from extracted human teeth with remaining marginal gingival tissue. The specimens were fixed with 2% glutaraldehyde in O.15M sodium cacodylate buffer (pH 7.2) for 24 h. The specimens were then washed and freeze-fractured in Freon 113 using liquid nitrogen. Afterwards they were processed by freeze-drying or CPD methods, coated with gold, and placed in …