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Comparative Analysis Of Patch Lesions In The Chick Inner Ear Following Acoustic Trauma: Optical Versus Scanning Electron Microscopy, H. J. Adler, J. Mantooth, Y. Raphael

Scanning Microscopy

Neonatal chicks were exposed to an octave band noise with a center frequency of 1.5 kHz at 116 dB SPL for 4 hours. Seven days following overstimulation, the birds were sacrificed. Their basilar papillae were re-moved, fixed in 4% paraformaldehyde, and processed in two steps. First, the ears were immunostained with a supernatant of mouse anti-tectorial membrane antibodies, followed by a diaminobenzidine process. Examinations of the papillae under an optical stereo microscope revealed a patch site with a partially regenerated tectorial membrane (referred to as the honeycomb).

After the optical studies, the same ears were post-fixed in 1% osmium tetroxide, …

Consistency In Calibrated Backscattered Electron Images Of Calcified Tissues And Minerals Analyzed In Multiple Imaging Sessions, E. G. Vajda, J. G. Skedros, R. D. Bloebaum

Scanning Microscopy

Pure metal standards have been used to calibrate the operating environment in quantitative backscattered electron (BSE) imaging of mineralized tissue, allowing comparisons to be made between various mineralization states of bone at the microscopic level. It has not previously been documented that calibration procedures produce consistent, reliable results over multiple imaging sessions. In this study, BSE images were obtained from bones, pure metals, and a naturally occurring mineral in multiple imaging sessions over a six day period. The graylevel histogram profile (GHP) from each specimen was analyzed for changes in the shape and relative placement on the graylevel spectrum. Computer …

Backscattered Electron Imaging And Energy-Dispersive X-Ray Microanalysis Studies Of Evidence For Calcium Salt Heterogeneity In Fifteen Gallstones From An Elderly Human, Tetsuo Kodaka, Ryoichi Mori, Kazuhiro Debari, Reiji Takiguchi, Shohei Higashi

Scanning Microscopy

We examined 15 variably-sized gallstones, taken from an elderly male, by backscattered electron imaging and energy-dispersive X-ray microanalysis to learn the structural and distribution patterns of gallstone calcium (Ca-) salts. Of the 13 cholesterol-rich stones, nine stones had peripheral concentric layers of Ca-carbonate, whereas 2 stones had peripheral layers of Ca-phosphate. No Ca-salts were detected from 2 cholesterol-rich stones. The 2 stones containing Ca-phosphate had no Ca-salt cores, whereas the stones containing Ca-carbonate were separated into 3 different types: two stones with a Ca-carbonate core, four stones with several Ca-bilirubinate cores of glass-like structure, and 3 stones lacking Ca-salt cores. …

Confocal Laser Scanning Microscopic Studies On Alveolar Bone Remodeling With Orthodontic Tooth Movement And Retention, H. Yagishita, S. Iwatsubo, T. Aoba

Scanning Microscopy

Alveolar bone reconstruction in growing dog during the retention period following orthodontic tooth movement was studied. Three beagle dogs (8-10 kg body weight, about one-year-old) were used and two of the animals were subjected to histological observation. The upper 2nd and lower 3rd premolars on both sides were extracted prior to the orthodontic treatments. After a healing period of one month, the upper 3rd premolar and the lower 4th premolar on the right side were moved mesially with a conventional orthodontic force for 8 weeks, and then retained in their new position for 4 weeks. The contralateral corresponding premolars were …

Analysis Of Glycosaminoglycans Induced In Newly Formed Calcium Oxalate Crystals Using An Undiluted Urine System, Koji Suzuki, Ryuzo Tsugawa

Scanning Microscopy

The aim of this study was to examine the effect of sodium pentosan polysulfate (SPP) in an undiluted urine system and to study its relative affinity to calcium oxalate (CaOx) crystals in the presence or absence of heparan sulfate (HS). CaOx crystals were induced with an overload of oxalate above the metastable limit in spun and filtered urine (SF) and ultrafiltered urine (UF). Then, the crystals were dissolved with EDTA (ethylene-diaminetetraacetic acid), electrodialysed and lyophilized. The polyanions, HS or SPP were added to the UF prior to the addition of oxalate. Polyanions in crystal matrices were examined by cellulose acetate …

Improved Methods For Preserving Macromolecular Structures And Visualizing Them By Fluorescence And Scanning Electron Microscopy, Paul B. Bell Jr., Barbara Safiejko-Mroczka

Scanning Microscopy

To determine the optimal procedures to preserve cytoskeletal and other macromolecular structures for microscopic studies we have evaluated the effects of various methods to extract cultured cells. In this report, we compare results using different fixatives, crosslinking reagents, and permeabilization methods on (1) the labeling of cells for fluorescence microscopy with phalloidin or antibody against tubulin; and (2) the morphological preservation of macromolecular structures for scanning electron microscopy. Maximal labeling of F-actin with phalloidin was obtained by fixing cells in 4% para formaldehyde (PFA) and labeling the unextracted cells with methanolic phalloidin, whereas maximal labeling of tubulin required prefixation with …

Optimal Pumping Strategies To Maximize Dissolved Tce Extraction At Central Base Area, Norton Afb, California, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Norton Air Force Base (NAFB) is located in the San Bernardino Valley, part of the California Peninsular Range geomorphic province (Figure 1). The elevation at NAFB is about 1,100 feet above mean sea level (msl). The ground slopes gradually to the southwest.

Noxious Weeds...A Biological Wildfire, Steven A. Dewey

All Current Publications

Invasive noxious weeds have been described as a raging biological wildfire—out of control, and spreading rapidly. The devastation from these alien plants includes enormous economic losses to agriculture and irreparable ecological damage to wildlands

Scanning Electron Microscopy And Energy Dispersive Spectroscopy Analysis Of Calciotraumatic Lines In Rat Labial Dentin After Acute Exposure To Strontium Chloride, Hiroyuki Mishima, Toshiro Sakae, Yukishige Kozawa

Scanning Microscopy

Rats were given strontium chloride (SrCli) intraperitoneally at a dose of 500 mg/kg. The upper incisors were removed after injection of strontium. These incisors were studied by scanning electron microscopy - energy dispersive spectroscopy analysis (SEM-EDS) and light microscopy to examine the calciotraumatic lines of strontium in the rat incisor labial dentin.

At 24 hours after injection of strontium, the calciotraumatic response was observed in the predentin using hematoxylin and eosin (H-E) staining. At 5 days, three layers of calciotraurnatic lines were present in the labial dentin using an H-E staining and backscattered electron imaging in the SEM. The external …

Tip-Induced Modifications In Scanning Tunneling Microscopy And Atomic Force Microscopy, K. Cho, J. D. Joannopoulos

Scanning Microscopy

Tip-induced modifications of microscopic processes in scanning tunneling microscopy (STM) and atomic force microscopy (AFM) of the Si(l00) surface are investigated with ab initio total energy pseudopotential calculations. The results of the calculations lead to a new understanding of the microscopic STM measurement process and the micro-mechanical changes (hysteresis and plastic deformation) in the AFM process. In particular, in the latter case, the results predict that the tip can be used to flip dimers on the surface, from one buckled configuration to the other, reversibly, and without inducing damage to either the intrinsic surface or the tip.

The Morphological Effects Of Two Antimicrobial Peptides, Hecate-1 And Melittin, On Escherichia Coli, William G. Henk, William J. Todd, Frederick M. Enright, Pamela S. Mitchell

Scanning Microscopy

The effects of the 26 amino acid, cationic, amphipathic, antibacterial peptide melittin and hecate-1, a 23 amino acid analog of it, on the gram negative bacterium Escherichia coli were investigated using scanning electron microscopy (SEM), transmission electron micros-copy (TEM), and freeze-fracture. Both peptides killed virtually all bacteria at the peptide concentration and cell density used. TEM and SEM revealed aggregates of bacteria entangled with material extruded from the bacterial surfaces. SEM revealed irregular bacterial surfaces with bleb-like projections. TEM and freeze-fracture indicate that the bacterial inner and outer membranes, as well as the peptidoglycan layer between, were extensively damaged. The …

Use Of Colloidal Gold And Neutron Activation In Correlative Microscopic Labeling And Label Quantitation, B. J. Darien, P. A. Sims, K. T. Kruse-Elliott, T. S. Homan, R. J. Cashwell, A. J. Cooley, R. M. Albrecht

Scanning Microscopy

Albumin was conjugated to 16 nm gold particles (Alb-Au16) and infused into anesthetized pigs to determine if plasma, tissue and bronchoalveolar lavage (BAL) fluid concentrations of gold could be quantitated by neutron activation (Au198). Additionally, transmission electron microscopy (TEM) of lung and liver samples was evaluated for sites of gold distribution and morphological changes. The minimum concentration of gold detected by neutron activation ranged between 1.4 and 1.9 ppb (ng/gm of sample). No gold was detected in the plasma of pigs prior to Alb-Au16 infusion, while mean post infusion concentrations were 1.037 ± 0.69 ppm (μg/gm plasma, ±SD). The concentrations …

Heterogeneous Nucleation Of Calcium Oxalate Crystals In Mammalian Urine, Saeed R. Khan

Scanning Microscopy

It is generally recognized that calcium oxalate crystal formation in urine is induced by heterogeneous nucleation. However, there is no consensus as to the nature of the nucleation substrate. Evidence is provided in this paper that membranous cellular degradation products are the most likely candidates because they: (1) are ubiquitous in urine and urinary stones; (2) are found in close association with crystal deposits in the kidneys; and (3) can induce nucleation of crystals from a meta-stable solution of calcium oxalate in vitro and metastable urine in vivo.

Imaging Of The Cytoplasmic Leaflet Of The Plasma Membrane By Atomic Force Microscopy, C. Le Grimellec, E. Lesniewska, M. -C. Giocondi, C. Cachia, J. P. Schreiber, J. P. Goudonnet

Scanning Microscopy

The cytoplasmic face of ventral cell membranes of Madin-Darby canine kidney (MDCK) cells grown on glass coverslips was imaged by atomic force microscopy (AFM) in air and under aqueous medium, in "contact" mode. Micrometer range scans on air-dried samples revealed a heterogeneous structure with some filaments, likely corresponding to actin filaments that abut the inner leaflet of the membrane, and a few semi-organized lattice structures that might correspond to clathrin lattices. Experiments in phosphate-buffered saline confirmed the heterogeneity of the inner membrane surface with the presence of large (> 100 nm) globular structures emerging from the surface. Using sub-micrometer scan …

Heterogeneous Distribution Of Ecto-Ca-Atpases In Primary Cultures Of Human Adenohypophyseal Cells, A. Kittel, I. Miklos, E. Bacsy

Scanning Microscopy

The aim of this study was to investigate the localization of ecto-Ca-adenosine-triphosphatase (ecto-Ca-ATPase) in different parenchymal cells of the human pituitary in tissue culture. The distribution of ecto-ATPases on the surface membrane of a particular parenchymal cell varied with the type of cells in contact with this parenchymal cell; the membrane portions immediately exposed to the medium showed low if any ecto-ATPase activity. These results suggest that ecto-Ca-ATPases of the parenchymal cells may be involved in cell adhesion processes and may be of crucial importance in the organization (in vivo) and reorganization (in vitro) of human …

Scanning Electron Microscope Study Of The Healing Molar Tooth Extraction Socket In The Rat, M. D. Mcmillan

Scanning Microscopy

Healing molar tooth extraction wounds in rats were examined by scanning electron microscopy from 15 minutes to 40 days following tooth removal. The wound epithelium, which was derived mainly from the gingiva but also from the cheek and hard palate, migrated be-neath the superficial socket contents. The contents were lost between 5 to 11 days, thus leaving a central epithelial-lined depression. This decreased in width with time as the level of the wound epithelium approached that of the hard palate but was still present at 40 days. Between 5 and 7 days, the wound epithelium became more regular. However, from …

The Interaction Of Laser Energy With Ureter Tissues In A Long Term Investigation, U. Stratmann, K. Schaarschmidt, R. R. Lehmann, A. Heinze, G. H. Willital, E. Unsold

Scanning Microscopy

This study investigates tissue responses after laser irradiation of the rabbit ureter, which serves as an experimental model for rectourogenital fistulae of children. Twenty-five rabbit ureters were irradiated intraluminally by a Nd:YAG laser 1320 nm (2 Watt, 20 seconds and 3 Watt, 8 seconds) via an applicator with radialsymmetrical light distribution. Immediately, 2 weeks, 4 weeks, 8 weeks, and 16 weeks after irradiation, the ureters were X-rayed with contrast solution and prepared for light and transmission electron microscopy. For the parameters employed, no apparent morphological differences could be observed. Immediately, the central laser zone showed a transmural therrnonecrosis prevailed by …

Imaging Of Single Antigens, Antibodies, And Specific Immunocomplex Formation By Scanning Force Microscopy, Arjan P. Quist, Anna A. Bergman, Curt T. Reimann, Sven O. Oscarsson, Bo U. R. Sundqvist

Scanning Microscopy

The most sensitive analytical techniques available today for detecting immuno assay complexes are radio or enzyme immuno analytical techniques, by which quantities of 10⁷-10⁸ analyte molecules can be detected. With the introduction of scanning force microscopy, a new method for detecting biological processes became available. Here, we examine the feasibility of using scanning force microscopy as a biosensitive tool. We demonstrate that single or multiple rabbit anti-human serum albumin molecules form complexes with preadsorbed single human serum albumin molecules on mica. However, no interaction is observed between human immunoglobulin G molecules and preadsorbed single albumin molecules; only …

Simulation Of Electron Emission From Beryllium Under Electron And Ion Bombardments, Kaoru Ohya, Jun Kawata

Scanning Microscopy

A Monte Carlo simulation model of particle-induced electron emission from beryllium, a candidate material for use on the wall in thermonuclear fusion devices, is developed. Comparative studies between secondary electron emission by electron bombardment and kinetic electron emission by proton bombardment reveal some interesting similarities and differences. The kinetic emission of electrons under heavy-ion bombardment is simulated as well for analyzing the effect of the initial charge state and mass of projectile ions on the kinetic emission. Furthermore, the model is applied to bowl-and-ripple structures for the study of surface roughness effects on the energy and angular distributions of secondary …

Dynamics Of Vortices In Superconductors Observed By Electron Waves, Akira Tonomura

Scanning Microscopy

Although, in electron microscopy, an object is usually observed by using the intensity of an electron beam transmitted through it, the phase distribution of the electron beam also provides different information about the object. It has been difficult, however, to obtain the phase information because of the low coherence of an electron beam. Recent development of a "coherent" field emission electron beam and related techniques, such as electron holography, has provided a way to observe microscopic objects and fields by precisely measuring the phase information of an electron beam. It has, for example, become possible to observe the dynamics of …

Scanning Force Microscopy Of Chromatin, Wolfgang Fritzsche, James Vesenka, Eric Henderson

Scanning Microscopy

Scanning force microscopy (SFM) is a new method to obtain the topography of surfaces with nanometer-resolution. The ability to image under liquids makes the technique attractive for biological applications, especially for the determination of the ultrastructure of biomolecules under native conditions. One growing field of interest is the investigation of chromatin and chromatin-related structures. Different levels of chromatin condensation were the subject of several previous SFM investigations, from the nucleosomal chain, to the 30-nm fiber, ending with the metaphase chromosome. The SFM yielded new information on such fundamental problems as the core spacing of the nucleosomal chain, the internal structure …

The Ampullae Of The Inner Ear In The Lizard Podarcis S. Sicula. Ultrastructural Aspects, G. Balsamo, B. Avallone, D. Calabro, F. Marmo

Scanning Microscopy

The inner ear ampullae of the lizard Podarcis s. sicula were studied to determine better the ultrastructure of ampullar epithelial cells.

Our study confirmed that the ampullae of the membranous labyrinth of this lizard are similar to those of other vertebrates in their ultrastructural aspect.

Moreover, our observations revealed a special type of dark cells, restricted to a small area of the crista. They appeared similar to type II sensory cells and showed a dark, finely granular cytoplasm, containing numerous mitochondria and ribosomes, extensive Golgi apparatus and abundant glycogen.

The morphology of these cells suggests that they may be …

Scanning Tunneling Microscopy Studies Of Chloroplasts In Solution, Douglas C. Dahn, Katrina Cake, T. Lynn Macdonald, Lawrence R. Hale

Scanning Microscopy

Previous work has shown that it is possible to image whole uncoated chloroplasts using scanning tunneling microscopy (STM), provided this is done in solution using tunnelling currents below about 100 pA.

More recent images include some which suggest that the STM is sensitive to dynamic processes occurring on chloroplast surfaces. Current-versus-distance curves and dI/ds measurements are consistent with tunnelling between the tip and sample surface, and relatively small deformations of the sample surface due to tip-sample forces. Attempts to use the same imaging conditions on bacteria were unsuccessful.

Mammalian Enamel Prism Patterns And Enamel Deposition Rates, Elizabeth R. Dumont

Scanning Microscopy

Enamel prism patterns and enamel deposition rates were compared for specimens representing six mammalian orders. Enamel samples were characterized by either pattern 1 or pattern 3 prisms. Each prism pattern cate-gory contained prisms from at least two mammalian orders. Enamel deposition rate was estimated for each sample by measuring prism cross striation repeat intervals. Statistical analysis of cross striation repeat intervals illustrates significant differences in deposition rate between prism patterns 1 and 3. No statistically significant differences were found in deposition rate between the higher-level taxa represented within each prism pat-tern category. That enamel deposition rate is not taxon-specific reinforces …

Low Concentrations Of Mercury Induce Changes In Ion Composition Of Cultured Myoblasts, Joanna Wroblewski, Jan Ekstrand, Romuald Wroblewski

Scanning Microscopy

The effects of low concentrations (1 pM, 1 nM, 1 μM) of mercuric chloride on ion distribution in cultured myoblasts were analysed by energy dispersive X-ray microanalysis. An increase in intracellular sodium concentration was observed five minutes after addition of HgC12 to the culture medium. This increase was dose dependent and accompanied by a transient decrease in potassium concentration. Exposure to 1 nM and 1 μM HgC12 led to a two-fold increase in the cytoplasmic chlorine concentration. The higher HgC12 concentration (1 μM) induced morphological alterations in the form of cell membrane blebs, perforations and shrinkage or flattening of the …

Aspen Decline In The Inland Northwest: A Review Of Some Relevant Literature, M. Brown

Aspen Bibliography

This paper reviews recent scientific literature about the biology and management of quaking aspen (Populus tremuloides Michx.) and relates it to the current decline of aspen in Oregon and Washington.

Cross-Linking Of Cell Surface Receptors As A Trigger Of Cell Apoptosis And Proliferation, Yuri N. Korystov

Scanning Microscopy

A hypothesis of the mechanism by which the protein cross-linking agents trigger apoptosis of lymphoid cells and proliferation of other cell types is proposed. It is assumed that both effects are triggered by aggregation of receptors on cell surface, which results from their cross-linking. This idea is substantiated by the example of one of these agents, ionizing radiation. As in the case of physiological agents, such as, antigens and growth factors, the aggregation of receptors induced by radiation activates receptor protein tyrosine kinases from which the signal is transduced to genes through protein kinase C. The hypothesis is consistent with …

From Scattering And Recoiling Spectrometry To Scattering And Recoiling Imaging, M. M. Sung, V. Bykov, A. Al-Bayati, C. Kim, S. S. Todorov, J. W. Rabalais

Scanning Microscopy

A new ion scattering technique, called scattering and recoiling imaging spectrometry (SARIS), is being developed. The SARIS technique uses a large, position sensitive microchannel plate (MCP) and time-of-flight methods to capture images of scattered and recoiled particles from a pulsed ke V ion beam. These images combine the advantage of atomic scale microscopy and spatial averaging simultaneously since they are created from a macroscopic surface area but they are directly related to the atomic arrangement of the surface. This paper de-scribes the basis of the SARIS technique, the instrument which is under development, and the scattering and recoiling …

Characterization Of Aspen Isoprene Synthase, An Enzyme Responsible For Leaf Isoprene Emission To The Atmosphere, Gary M. Silver, Ray Fall

Aspen Bibliography

Isoprene (2-methyl-1,3-butadiene) is a volatile hydrocarbon emitted from many plant species to the atmosphere, where it plays an important role in atmospheric chemistry. An enzyme extracted from aspen (Populus tremuloides) leaves was previously found to catalyze the Mg2+-dependent elimination of pyrophosphate from dimethylallyl diphosphate (DMAPP) to form isoprene (Silver, G. M., and Fall, R.(1991) Plant Physiol. 97, 1588-1591). This enzyme, isoprene synthase, has now been purified 4000-fold to near homogeneity. The enzyme had a native molecular mass of 98-137 kDa and isoelectric point of 4.7 and contained 58- and 62-kDa subunits, implying that it is a heterodimer. …

Brine Shrimp Ecology In The Great Salt Lake, Utah, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Hypersaline lakes are noted for their simple communities which facilitate understanding ecological interactions (Williams et al. 1990; Wurtsbaugh 1992; Jellison and Melack 1988). Nevertheless, we still cannot easily predict how environmental changes will effect the population dynamics in these lakes, at least in part because even these simple ecosystems may be more complex than we .realize. Many hypersaline lakes are dominated by the brine shrimp Artemia spp. The production of brine shrimp is often very high because the terminal, saline lakes accumulate nutrients that make them rich, and because the short food chains in them (nutrients-->phytoplankton-->brine shrimp) minim …