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The Nucleation And Growth Of Calcium Oxalate Monohydrate On Self-Assembled Monolayers (Sams), Allison A. Campbell, Glen E. Fryxell, Gordon L. Graff, Peter C. Rieke, Barbara J. Tarasevich

Scanning Microscopy

A physical chemical approach was used to study calcium oxalate monohydrate (COM) nucleation and growth on various organic interfaces. Self-assembling monolayers (SAMs), containing derivatized organic functional groups, were designed to mimic various amino acid residues present in both urine and stone matrix macromolecules. Derivatized surfaces include SAMs with terminal methyl, bromo, imidazole, and thiazolidine-carboxylic acid functional groups. Pronounced differences in COM deposition were observed for the various interfaces with the imidazole and thiazolidine surfaces having the greatest effect and the methyl and bromo groups having little or no nucleating potential.

The Use Of Sonic Frequencies As A Cleaning Agent Of Specimens To Be Observed By Scanning Electron Microscopy, G. Familiari, A. Familiari, G. Macchiarelli, L. J. A. Didio, P. M. Motta

Scanning Microscopy

The presence of mucus and/or cellular debris can obscure the fine morphology of the gastrointestinal or respiratory luminal surface, when observed by scanning electron microscopy. With the intent of obtaining a good cleaning of the mucosal surface without altering the ultrafine morphology of epithelial cells, a new model of sonicator/ultrasonicator is presented.

The instrument is supplied with a control system for wave frequency, amplitude and form, and permits a precise regulation of the wave energy. With this instrument it is possible to produce a "cleaning effect" by using any kind of frequency (either sonic or ultrasonic) and/or amplitude and/or waveform …

Influence Of 17-B-Estradiol And Progesterone On The In Vitro Cultured Mouse Preimplantation Embryos, Matthew L. Offutt

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Arts and Sciences at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Matthew L. Offutt on December 10, 1992.

Cellular Interactions In Hemopoietic Progenitor Cell Homing: A Review, Cheryl L. Hardy, Jose J. Minguell

Scanning Microscopy

Within the bone marrow microenvironment, dynamic cellular interactions are constantly occurring. These interactions involve hemopoietic stem cells, progenitor cells and maturing cells, physically interacting with other cells, some of which may function as accessory cells, and others which comprise the stromal elements; hemopoietic cells also interact with non-cellular elements, such as glycoproteins and fibrous proteins of the extracellular matrix (ECM). These interactions serve to regulate normal hemopoiesis by allowing the communication of regulatory information, migration and subsequent homing of stem cells within specific organs, and presentation of hemopoietic growth factors in a biologically relevant fashion. The goal of this review …

Bacterial Numbers And Activity, Microalgal Biomass And Productivity, And Meiofaunal Distribution In Sediments Naturally Contaminated With Biogenic Bromophenols, Charles C. Steward, James L. Pinckney, Yvette Piceno, Charles R. Lovell

Faculty Publications

Sediment cores were collected inside and outside of a bed of a bromophenol-producing marine polychaete, Notomastus lobatus, and examined for impact of the bromophenols on sediment microflora and meiofauna around N. lobatus burrows. No significant differences were found between microbial parameters measured inside and outside of the N. lobatus bed. Integrated 6 cm cores taken adjacent to N. lobatus burrows contained 1.2 x 10⁹ bacteria ml^-1. Cell numbers were similar at control sites within the bed, but away from burrows, and not significantly different from cell numbers (1.0 X 10⁹ cells ml^-1) at a …

Sediment-Water Nutrient Flux In Tidal Creeks Of North Inlet, South Carolina, Michael Duane Quillen

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Arts and Sciences at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Michael Duane Quillen on December 7, 1992.

Early Behavior Formation In Larval Fathead Minnows, Pimephales Promelas, Shamali Salgado

Masters Theses & Specialist Projects

This study was undertaken in order to identify the approximate times of recruitment of the senses of vision, mechanoreception and chemoreception into the feeding behavior of the fathead minnow, Pimephales promelas, during the first 15 days of life. Larvae were reared on diets of live or freshly killed brine shrimp nauplii and their feeding activity observed daily under light and dark conditions. On every third day during the feeding trials, the larvae were reverse-fed the type of food upon which they were reared. The first evidence of feeding occurred on Day 3, when larvae conditioned on dead food ingested …

The Expression Pattern Of The Tonoplast Intrinsic Protein Γ-Tip In Arabidopsis Thaliana Is Correlated With Cell Enlargement, Edward Himelblau, Herman Hofte, Dolors Ludevid, Maarten J. Chrispeels

Biological Sciences

The vacuolar membrane (tonoplast) contains an abundant intrinsic protein with six membrane-spanning domains that is encoded by a small gene family. Different isoforms of tonoplast intrinsic protein (TIP) are expressed in different tissues or as a result of specific signals. Using promoter-β-glucuronidase (GUS) fusions and in situ hybridization, we have examined the expression of γ-TIP in Arabidopsis thaliana. GUS staining of plants transformed with promoter-GUS fusions showed that γ-TIP gene expression is high in recently formed tissues of young roots. In the shoot, γ-TIP gene expression was highest in the vascular bundles of stems and petioles, as well as …

Elucidation Of The Complete Azorhizobium Nicotinate Catabolism Pathway, Christopher Kitts, Jerome P. Lapointe, Van Thai Lam, Robert A. Ludwig

Biological Sciences

A complete pathway for Azorhizobium caulinodans nicotinate catabolism has been determined from mutant phenotype analyses, isolation of metabolic intermediates, and structural studies. Nicotinate serves as a respiratory electron donor to O₂ via a membrane-bound hydroxylase and a specific c-type cytochrome oxidase. The resulting oxidized product, 6-hydroxynicotinate, is next reduced to 1,4,5,6-tetrahydro-6-oxonicotinate. Hydrolytic ring breakage follows, with release of pyridine N as ammonium. Decarboxylation then releases the nicotinate C-7 carboxyl group as CO₂, and the remaining C skeleton is then oxidized to yield glutarate. Transthioesterification with succinyl coenzyme A (succinyl-CoA) yields glutaryl-CoA, which is then oxidatively decarboxylated to …

Gene Probe Analysis Of Soil Microbial Populations Selected By Amendment With 2,4-Dichlorophenoxyacetic Acid, William Holben, B. M. Schroeter, V. G.M. Calabrese, R. H. Olsen, J. K. Kukor, V. O. Biederbeck, James M. Tiedje

Biological Sciences Faculty Publications

Soils with a history of 2,4-dichlorophenoxyacetic acid (2,4-D) treatment at field application rates and control soils with no prior exposure to 2,4-D were amended with 2,4-D in the laboratory. Before and during these treatments, the populations of 2,4-D-degrading bacteria were monitored by most-probable-number (MPN) enumeration and hybridization analyses, using probes for the tfd genes of plasmid pJP4, which encode enzymes for 2,4-D degradation. Data obtained by these alternate methods were compared. Several months after the most recent field application of 2,4-D (approximately 1 ppm), soils with a 42-year history of 2,4-D treatment did not have significantly higher numbers of 2,4-D-degrading …

Progress In Scanning Electron Microscopy Of Frozen-Hydrated Biological Specimens, René Hermann, Martin Müller

Scanning Microscopy

Modem scanning electron microscopy yields structural information down to 2 to 5 nm from thin, beam transparent biological specimens. This paper examines the possibilities of garnering this level of structural information from bulk, frozen-hydrated samples.

Freeze-fractured, frozen-hydrated yeast cells, frequently taken as a yardstick to monitor progress in low-temperature scanning electron microscopy, have been used to optimize both metal shadowing methods and observation parameters (e.g. accelerating voltage, electron beam irradiation of the specimen).

Uncoated frozen-hydrated yeast cells do not charge electrically at an accelerating voltage of 30 kV. Increasing charging effects are however observed with decreasing accelerating voltages. Very thin …

Scanning Laser Microscopic Surface Profiles Of Human Enamel And Dentin After Brushing With Abrasive Dentifrice In Vitro, Tetsuo Kodaka, Masaru Kuroiwa, Megumi Kobori

Scanning Microscopy

Automatic brushing with and without commercial dentifrice containing calcium hydrogenphosphate as an abrasive, commonly available in Japan, was performed on the tangential ground surfaces of sound enamel and dentin in human young premolar teeth with loading of about 120 g for 10 minutes in vitro. Their brushed surfaces were observed with a scanning electron and a scanning laser microscope. Brushing with abrasive dentifrice caused rough surfaces to appear and the abrasion of the enamel and the dentin was measured to be about 0.1 and 1.5 μm/min in mean depth, respectively. Under brushing with only distilled water, however, the enamel …

Retinol Deficiency And Urinary Stone Disease: Clinical Evidence Is Missing, P. P. Singh, R. Kiran

Scanning Microscopy

Serum retinal levels were studied in : (a) 95, 56 and 43 normal subjects belonging to lower, middle and upper socio-economic groups respectively, (b) 35 adult males suffering from night blindness, (c) 27 subjects with low retinal levels, (d) 8 retinal deficient subjects (e) 17 male infants suffering from overt retinal deficiency, (f) 43 radiologically confirmed stone patients and (g) age and sex matched controls (infants 20; adults 120). The subjects included in groups b to f were clinically and radiologically examined for stone disease. Some inhibitors and promoters of stone disease were estimated in urine in groups b to …

The Tale Of Parathyroid Function In Idiopathic Hypercalciuria, Bernhard Hess, Philippe Jaeger

Scanning Microscopy

At the origin, idiopathic hypercalciuria has been described as a syndrome consisting of normocalcemia, low plasma phosphate levels and abnormally high urinary calcium excretion. The cause of this syndrome was subject to many investigations throughout the years. Two main pathophysiologic hypotheses have been proposed: a) primary intestinal hyperabsorption of calcium, leading to depression of parathyroid hormone (PTH) secretion ("absorptive" hypercalciuria); and b) primary renal tubular leak of calcium which stimulates PTH secretion (secondary hyperparathyroidism). Most of the published studies indicate that intestinal hyperabsorption of calcium with subsequent relative hypoparathyroidism is the primary event causing idiopathic hypercalciuria, and that …

Study Of Surface Modified Poly(Ethylene) Yarns, Samuel H. Cohen, Heidi Schreuder-Gibson, John T. Stapler

Scanning Microscopy

Spectra® fibers and fabrics have been treated to enhance surface friction to determine if ballistic penetration resistance of Spectra fabric can be increased with improved interfiber friction. Scanning electron microscopy (SEM) has shown the extent of surface modification for plasma treated Spectra yarns and the uniformity of coverage for dip-coated yarns and fabrics. Of particular interest is the observation by SEM that plasma gases etch the surface of the polyethylene, producing varying effects on the fiber surface friction. While difficult to measure spectroscopically, the presence of coatings that affect fiber friction are confirmed by SEM.

Strontium, A Tracer To Study The Transport Of Calcium In Mineralizing Tissues By Electron Probe Microanalysis, Ernst-Rudolf Krefting, Kai Frentzel, Jörg Teßarek, Hans-Jürgen Höhling

Scanning Microscopy

In growth plate cartilage the mineralization starts extracellularly in the lower hypertrophic zone. The mineral formed is the calcium phosphate apatite. Enough calcium and phosphate must be available at the mineralization front as well as in regions with proceeding mineralization. There must be a transport of Ca (and phosphate) to these sites.

Electron probe X-ray microanalysis is a well established method to analyze element concentrations in small volumes, but it cannot discriminate isotopes. Strontium is similar to Ca in its chemical and biological behaviour and is therefore a suitable tracer to investigate the transport of Ca.

Small amounts of Sr …

Strained And Relaxed Semiconducting Silicide Layers Heteroepitaxially Grown On Silicon, J. Chevrier, Le Thanh Vinh, J. Derrien

Scanning Microscopy

The semiconducting silicide ß-FeSi₂, which can be grown epitaxially on silicon, is potentially an interesting material for integrated optoelectronic devices. Its semiconducting state stabilised by a solid state Jahn Teller effect is very unusual. Indeed the epitaxial growth of FeSi₂ on silicon (111) in a Molecular Beam Epitaxy (MBE) chamber has revealed the existence of a metallic strained FeSi₂ phase which is the result of a simultaneous electronic and structural transition. The stability and the relaxation of this strained phase which is specifically due to the epitaxy of FeSi₂ on the silicon (111) face …

Effects Of Citrate On The Different Phases Of Calcium Oxalate Crystallization, H. -G. Tiselius, C. Berg, A. -M. Fornander, M. -A. Nilsson

Scanning Microscopy

Urinary citrate appears to be an important factor in the crystallization process of calcium oxalate and calcium phosphate. The urinary excretion of citrate was found to be significantly lower in patients with calcium oxalate stone disease as compared with normal subjects, and about 30 per cent of the calcium stone formers can be considered as hypocitraturic. The lowest excretion of citrate was recorded in urine collected during the night. Citrate has significant effects on supersaturation with respect to both calcium oxalate and calcium phosphate, it also inhibits the growth of these crystals. In addition, citrate appears to be capable of …

Review: Morphological Changes Associated With Endolymphatic Hydrops, K. C. Horner

Scanning Microscopy

Endolymphatic hydrops of the inner ear is identified as a swelling of the endolymphatic spaces. This morphopathology in man can only be confirmed at postmortem examination although it is believed to underlie the auditory dysfunction and vestibular disturbances associated with Menière's disease. This is an illusive inner ear disorder characterized typically by the fluctuant hearing loss, tinnitus and episodes of vertigo. Menière's disease remains a major problem in otorhinolaryngology since the cause of the disease is not known and various treatments are recommended, often with unsatisfactory results. Experimentally induced endolymphatic hydrops in the animal model has been developed in order …

Long Term Mobidity And Mortality Of Adolescent Obesity: A Follow-Up Of Third Harvard Growth Study Participants Of 1922 To 1935, Aviva Must Ph.D., Paul F. Jacques Sc.D., Gerard E. Dallal Ph.D., Carl J. Bajema Ph.D., William H. Dietz M.D., Ph.D

Peer Reviewed Publications

Background. Overweight in adults is associated with increased morbidity and mortality. In contrast, the long-term effect of overweight in adolescence on morbidity and mortality is not known.

Methods. We studied the relation between overweight and morbidity and mortality in 508 lean or overweight adolescents 13 to 18 years old who participated in the Harvard Growth Study of 1922 to 1935. Overweight adolescents were defined as those with a body-mass index that on two occasions was greater than the 75th percentile in subjects of the same age and sex in a large national survey. Lean adolescents were defined as those with …

Mercox®-Methylmethacrylic Acid Mixture Penetrates Into Cells. A Scanning And Transmission Electron Microscopic Study, S. Aharinejad, P. Böck

Scanning Microscopy

During preparation of vascular casts using mixtures of Mercox® and methylmethacrylic acid for scanning electron microscopy, occasionally irregular structures were observed adhering to otherwise well prepared corrosion casts. These artifacts were further analyzed in sections of cast preparations. The bizarre-shaped structures varied in size and were often tightly connected to vascular casts; they withstood KOH maceration and cleaning with formic acid. The persistence of biological material, connective tissue fibers and cells or cellular fragments, became obvious in ultrathin sections. Transmission electron microscopy also showed inhomogeneity of the polymerized casting medium (Mercox®-methylmetbacrylate mixture; v/v: 4:1). An unidentified com-pound of this resin …

Time-Resolved Scanning Electron Microscopy Analysis Of Nanodynamical Structures, J. Jason Yao, Noel C. Macdonald

Scanning Microscopy

We have developed and characterized a time-resolved scanning electron microscopy (SEM) operational mode which provides non-destructive mechanical characterization of nanodynamical structures with 8-bit image resolution and 200 ns time resolution. This time-resolved SEM scheme does not require blanking plates, nor does it require any hardware modification to a commercially available scanning electron microscope. Both time-resolved images and line scan profiles of nanofabricated single crystal silicon tweezers are obtained. This time-resolved SEM operational mode can be used to evaluate a number of important mechanical properties of nanodynamical structures, including time response and resonance mode-shapes.

Cytogenetics Of Delphinium (Ranunculaceae) Species Native To Oregon, Jill Yeatman Turner

Dissertations and Theses

Evidence of hybridization, known to occur in the genus Delphinium (Ranunculaceae ), has recently been discovered among certain Delphinium species native to Oregon. This issue was investigated by cytogenetic analysis of four native species of Oregon, D. trolliifolium, D. menziesii, D. pavonaceum and D. leucophaeum, and an unidentified purple delphinium, which is possibly a hybrid. Although many species in this genus are karyotypically similar, any variations found among the karyotypes of these Oregon species might be used to identify parental chromosomes in the purple delphinium (proposed hybrid). Meiotic analysis was used to detect structurally heterozygous homologues that …

The Occurrence And Effect Of A Protozoan Parasite, Ophryocystis Elektroscirrha (Neogregarinida: Ophryocystidae) On Overwintering Monarch Butterflies, Danaus Plexippus (Lepidoptera: Danaidae) From Two California Winter Sites, Kingston L. H. Leong, H. K. Kaya, Michael A. Yoshimura, Dennis F. Frey

Biological Sciences

1. Monarch butterflies, Danaus plexippus, from two overwintering populations, were found to have Ophryocystis elektroscirrha spores on their scales at rates between 53% and 68%. The frequency of butterflies with O.elektroscirrhaspores remained about the same between sites and throughout the winter.

2. The spores, recovered from all parts of the body of the butterfly, were most numerous on the abdomen, particularly near the posterior third.

3. Butterflies with spores survived as long as those without detectable spores at 10.1°C ±0.4 SE and 78.3% r.h. ±0.6SE. Insects with spores held at 19.4°C ±0.4SE and 44.9% r.h. ±1.5SE showed a …

Heterochromatin Protein 1, A Known Suppressor Of Position-Effect Variegation, Is Highly Conserved In Drosophila, Robert F. Clark, Sarah C.R. Elgin

Biology Faculty Research

The Su(var)205 gene of Drosophila melanogaster encodes heterochromatin protein 1 (HP1), a protein located preferentially within beta-heterochromatin. Mutation of this gene has been associated with dominant suppression of position-effect variegation. We have cloned and sequenced the gene encoding HP1 from Drosophila virilis, a distantly related species. Comparison of the predicted amino acid sequence with Drosophila melanogaster HP1 shows two regions of strong homology, one near the N-terminus (57/61 amino acids identical) and the other near the C-terminus (62/68 amino acids identical) of the protein. Little homology is seen in the 5' and 3' untranslated portions of the gene, as well …

Southern Nevada Effluent Wetlands: A Proposed Cooperative Venture Between The Bureau Of Reclamation & City Of Las Vegas, Bureau Of Reclamation

Publications (WR)

Throughout North America there is a growing interest in constructed wetlands, both as relatively inexpensive, low-maintenance systems for removing nutrients from wastewater, and as a means of using municipal wastewater to enhance wildlife habitat and create public use opportunities. Because wetlands appear to have good potential as a component in the overall management of scarce water resources, the Bureau of Reclamation (Reclamation) has undertaken several cooperative research and demonstration projects to evaluate their effectiveness in a variety of local environments. While a number of projects have demonstrated that wetlands can be beneficially employed to improve water quality, few such projects …

Renal Stone Formation In Patients With Inflammatory Bowel Disease, R. Caudarella, E. Rizzoli, L. Pironi, N. Malavolta, G. Martelli, G. Poggioli, G. Gozzetti, M. Miglioli

Scanning Microscopy

Kidney stones are more common in patients with inflammatory bowel disease (IBD) than in the general population. The main lithogenetic risk factors were evaluated in patients affected by Crohn's disease and ulcerative colitis. Our results show the presence of several factors, besides hyperoxaluria, in patients with IBD although their behaviour appears different in Crohn's disease and ulcerative colitis at pre- and post-operative stages. Before surgery in patients with Crohn's disease we found a decreased citrate (p < 0.001) and magnesium (p < 0.005) excretion together with a low urinary volume (p < 0.001) and pH (p < 0.005). After surgery patients with Crohn's disease showed a further reduction of magnesium and citrate. Patients with ulcerative colitis before surgery showed a reduced citrate excretion (p < 0.05) and a more acidic pH (p < 0.05) than healthy subjects. Surgical treatment of proctocolectomy with ileal pouch-anal anastomosis seems to increase the risk of stone formation; in fact, after surgery we observed a relevant decrease of urinary volume (p < 0.001), pH (p < 0.0001) and urinary excretion of citrate (p <0.0001) as well as magnesium (p < 0.005). Patients with IBD seem to be at greater risk of stone formation than patients with idiopathic calcium lithiasis; in fact, they show a lower excretion of citrate (p < 0.001) and magnesium (p < 0.001) together with a low urinary pH (p < 0.001) and volume (p < 0.001). Urinary volume reduction is probably one of the major risk factors together with the decrease of small molecular weight inhibitors that is a constant finding in all patients with IBD.

Evaluation And Management Of Dietary Habits In Japanese Renal Stone Formers, Haruo Ito, Tadashi Kotake, Naoto Miura

Scanning Microscopy

To elucidate the relationship between the formation of kidney stones and diet, we carried out a dietary investigation in patients with urinary tract stones. Dietary intakes were estimated for 36 patients (24 men, 12 women) with calcium stones, and compared with the official dietary requirements for the Japanese.

Total protein intake, animal protein intake and animal protein ratio were significantly higher for patients with stones in both men and women. Dietary salt intake was significantly higher for male patients and the total group. Dietary calcium and carbohydrate intakes were significantly lower for patients with stones in men and the total …

Renal Tubular Hypouricemia And Calcium Urolithiasis, Tadashi Kotake, Naoto Miura, Haruo Ito

Scanning Microscopy

The information concerning the relationship of hypouricemia with urinary tract stones is limited. We investigated the incidence and types of hypouricemia, and also studied its relationship to urinary tract stones. Hypouricemia was detected in 3 out of 1520 outpatients (0.20%). The loading tests using pyrazinamide, probenecid and benzbromarone showed that uric acid absorption was impaired before tubular secretion in two cases and incomplete postsecretory reabsorption in one case. Complication of urinary tract stone was found in two cases. The composition of the stones was mixed calcium oxalate and uric acid. Hypouricemia should be recognized as one of the causes of …

Microanalysis Of Individual Silver Halide Microcrystals, Shijian Wu, A. Van Daele, W. Jacob, R. Gijbels, A. Verbeeck, R. De Keyzer

Scanning Microscopy

Elemental distributions and contents of tabular and cubic silver halide microcrystals were analyzed by backscattered electron imaging, scanning transmission electron imaging, X-ray mapping and X-ray analysis in the spot mode by scanning transmission electron microscopy (STEM) combined with energy-dispersive X-ray spectrometry (EDXS). By using a liquid nitrogen cryostage, damage to the microcrystals and drift of the sample under electron bombardment were minimized. Monte Carlo simulation shows the electron trajectories in the silver halide microcrystals for different experimental conditions and directs the selection of the beam position for X-ray spot analysis. The backscattered electron images, scanning transmission electron images and X-ray …