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Morphological And Chemical Properties Of Plastic Residues In Composts, Charles R. Krause, Leona E. Horst, Harry A. J. Hoitink Oct 1996

Morphological And Chemical Properties Of Plastic Residues In Composts, Charles R. Krause, Leona E. Horst, Harry A. J. Hoitink

Scanning Microscopy

The relative quantity of plastic film residues and other man-made materials in composts prepared from municipal solid wastes (MSW), biosolids, yard wastes, and pine bark was evaluated utilizing light and scanning electron microscopy equipped with energy dispersive X-ray analyzer. MSW composts screened through a 4 mm screen contained significant but highly variable quantities of plastic film residues and other man-made materials that escaped detection with the unaided eye. The other composts were free of such particles. We conclude that the database for evaluation of man-made materials in MSW composts is inadequate and must be developed further.


Pre-Embedding Staining Of Single Muscle Fibers For Light And Electron Microscopy Studies Of Subcellular Organization, Evelyn Ralston, Thorkil Ploug Jul 1996

Pre-Embedding Staining Of Single Muscle Fibers For Light And Electron Microscopy Studies Of Subcellular Organization, Evelyn Ralston, Thorkil Ploug

Scanning Microscopy

Skeletal muscle fibers are large, multinucleated cells which pose a challenge to the morphologist. In the course of studies of the distribution of the glucose transporter GLUT4, in muscle, we have compared different preparative procedures, for both light (LM) and electron microscopy (EM) immunocytochemistry. Here we show that pre-embedding staining of single teased fibers, or of single enzymatically dissociated fibers, has several advantages over the use of sections for observing discrete patterns that extend over long distances in the cells. We report on an optimization study carried out to establish fixation and permeabilization conditions for EM immunogold labeling of the …


Abundant Protein-Containing Particles In The Sea, Richard A. Long, Farooq Azam Jun 1996

Abundant Protein-Containing Particles In The Sea, Richard A. Long, Farooq Azam

Faculty Publications

The interaction of bacteria with particulate organic matter has implications for organic matter cycling and bacterial ecology in the ocean. Until recently, the focus has been on 'classical' particles visible by unaided eye (marine snow) or light microscopy. Recent discoveries of several new types of abundant particles, from sub-micrometer to sub-marine snow, are changing our ideas of the physical and chemical nature of the particle field with which pelagic bacteria interact. Previous workers have discovered polysaccharide-containing (Alcian Blue stainable) transparent exopolymer particles (TEP) ranging from 3 to 100s of micrometers. Looking for additional components of the sub-marine snow particle field, …


Common Epidermal Lesions Of The Bowhead Whale, Balaena Mysticetus, William G. Henk, Dianna L. Mullan Jun 1996

Common Epidermal Lesions Of The Bowhead Whale, Balaena Mysticetus, William G. Henk, Dianna L. Mullan

Scanning Microscopy

Samples of common skin abnormalities from 23 subsistence-harvested bowhead whales (Balaena mysticetus) were examined. Most lesions fell into three broad classes: shallow lacerations, circular depressions, and epidermal sloughing. Both circular depression lesions and epidermal sloughing lesions may be divided into more than one subgroup based on morphological criteria. Examination of each of the subgroups using light and scanning electron microscopy suggests relationships among the subgroups of a class. These proposed relationships are discussed, as are some possible etiologies. Scanning electron microscopy reveals abundant bacteria and diatoms present in association with each lesion class but no evidence of a particular association …


Temperature-Driven Variation In Substrate Oxygenation And The Balance Of Competition And Facilitation, Ragan M. Callaway, Leah King Jun 1996

Temperature-Driven Variation In Substrate Oxygenation And The Balance Of Competition And Facilitation, Ragan M. Callaway, Leah King

Biological Sciences Faculty Publications

Emergent wetland plants often alleviate the effects of anaerobic soils on root respiration by passively transporting oxygen belowground through continuous air spaces (aerenchyma) in leaves and roots. Oxygen leaked from the roots into the rhizosphere may oxidize minerals in the soil or become available to other plants. Some spatial patterns in marsh plant communities suggest interspecific facilitative interactions, but there is little experimental evidence for interplant facilitation via soil oxygenation. We investigated the capability of the widespread, highly aerenchymous wetland plant, Typa latifolia, to aerate sediments and affect the growth of two non—aerenchymous neighbors, Salix exigua and Myosotis laxa, both …


Low Calcium Diet In Hypercalciuric Calcium Nephrolithiasis: First Do No Harm, Bernhard Hess Jun 1996

Low Calcium Diet In Hypercalciuric Calcium Nephrolithiasis: First Do No Harm, Bernhard Hess

Scanning Microscopy

Many studies indicate that up-regulated production of 1,25(OH)2-vitamin D3 (calcitriol) with increased intestinal absorption of calcium is the primary event causing idiopathic hypercalciuria. Thus, a low calcium diet appears to be a straightforward strategy in calcium stone formers with hypercalciuria (HCSF). However, the efficacy of such a regimen has never been established, and lowering calcium intake from 1000 to 400 mg/day further enhances calcitriol production. On a diet chronically restricted in calcium, many stone formers increase their intake of animal flesh protein. The latter is known to increase renal mass, and calcitriol levels indeed are positively correlated with renal mass …


Touch-Plate And Statolith Formation In Graviceptors Of Ephyrae Which Developed While Weightless In Space, Dorothy B. Spangenberg, Elisa Coccaro, Russell Schwarte, Brian Lowe May 1996

Touch-Plate And Statolith Formation In Graviceptors Of Ephyrae Which Developed While Weightless In Space, Dorothy B. Spangenberg, Elisa Coccaro, Russell Schwarte, Brian Lowe

Scanning Microscopy

Ultrastructural studies of the statocysts and touch-plates of graviceptors (rhopalia) of Aurelia ephyrae revealed that (1) touch-plate hair cells are present; and (2) cytoplasmic strands from the hair cell bases extend from the neurite plexus to touch similar strands from the lithocytes. This close association of hair cell neurites and statocysts may have important implications regarding the transmitting and processing of positional information with respect to the gravity vector.

Graviceptors of ephyrae which developed while weightless in microgravity were compared with controls at the ultrastructural level. We found that hair cells of ephyrae which developed in microgravity had fewer lipid …


A Correlative Study Of An At-Risk Population And Low Birth Weight/Infant Mortality In A Northeast Oklahoma City Community, Estacia D. Thrower May 1996

A Correlative Study Of An At-Risk Population And Low Birth Weight/Infant Mortality In A Northeast Oklahoma City Community, Estacia D. Thrower

McCabe Thesis Collection

Studies show that numerous and complex variables influence pregnancy outcomes and infant mortality rates. These variables include demographic, medical, physical, environmental, behavioral, and attitudinal factors and prenatal care. Improving the health of mothers and infants is a national challenge. In 1987, more than 3.8 million infants were born in the United States. Of these, 38,408 died before their first birthday. Although the infant mortality rate is at an all-time low, the pace of progress has slowed. According to Dr. Robert Deppen of the Oklahoma State Health Department, "In 1992, Oklahoma ranked 29th in the United States for infant mortality and …


The Influence Of Bull Exposure And Bull Presence On Postpartum Reproductive Physiology And Behavior Of High-Producing Dairy Cows, Milan P. Shipka May 1996

The Influence Of Bull Exposure And Bull Presence On Postpartum Reproductive Physiology And Behavior Of High-Producing Dairy Cows, Milan P. Shipka

Biology

Bull exposure has been shown to hasten the onset of estrous cyclicity in postpartum beef cattle but has not been examined in high producing dairy cattle. This investigation was carried out to examine effects of bull presence on postpartum reproductive characteristics in dairy cattle. Forty-five multiparous dairy cattle were randomly allocated into three groups at the time of calving. Treatments consisted of no bull exposure (NBE), twice daily bull exposure (2xdBE), and continuous bull exposure (CBE). Estrus detection was carried out for all groups for one-half hour twice daily following milking. Systemic progesterone (P4) was determined from blood …


No Evidence Of Linkage Between 35 Genetic Markers And The Spider Lamb Syndrome Gene In Sheep, Sarah Thornell South May 1996

No Evidence Of Linkage Between 35 Genetic Markers And The Spider Lamb Syndrome Gene In Sheep, Sarah Thornell South

Undergraduate Honors Capstone Projects

Spider Lamb Syndrome (SLS) is a semi-lethal congenital disorder affecting the Suffolk and Hampshire sheep breeds. The clinical manifestations of the syndrome include severe skeletal and muscular abnormalities with long, fine-boned legs, curvature of the spine and nasal septum, minimal muscling and severe muscle atrophy. The affected animals have a difficult time walking and most lambs do not survive past the first six months of life. A single autosomal recessive gene causes the disorder. Researchers believe the SLS gene arose as a single source mutation in a popular Suffolk blood line in the 1970s. Heterozygous carriers of the SLS gene …


Association Of The Major Histocompatibility Complex With Autism, Wayne W. Daniels May 1996

Association Of The Major Histocompatibility Complex With Autism, Wayne W. Daniels

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The pathogenesis of autism has proven difficult to characterize. However, in many recent studies, it is suggested that the onset of this disorder is the result of multiple etiological factors, which include genetic, immunologic, and viral elements.

Possible immunological influences found in subpopulations of patients with autism include decreased lymphocyte responsiveness, reduced natural killer cell activity, abnormal response to rubella vaccine, abnormal immune response to brain tissue, and decreased plasma levels of the fourth component of complement(C4). These aberrations and others imply a possible autoimmune mechanism in some cases for the development of autism.

C4 deficiencies have been found in …


The Competition Of Pityopsis Ruthii With Liatris Microcephala And Andropogon Temarius, Helen Lee Apr 1996

The Competition Of Pityopsis Ruthii With Liatris Microcephala And Andropogon Temarius, Helen Lee

Capstone Research Projects

Pityopsis ruthii (Small) Small, currently listed as an endangered species by the State of Tennessee and the U.S. Fish and Wildlife Service, is a perennial plant belonging to the family Asteraceae. The distribution of P. ruthii is limited to soil that has accumulated in cracks and crevices of phyllite or graywacke boulders along the Ocoee and Hiwassee Rivers. Analysis of both the soil and the boulders indicate neither the absence nor the presence of any unusual nutrient. P. ruthii is most likely restricted to this habitat mainly because of its inability to compete with other more vigorously growing associates. The …


Effects Of Insulin And Insulin-Mimetics On Mrna Levels Of C-Fos And C-Jun In Primary Rat Hepatocytes In Culture, Guangmin Li Apr 1996

Effects Of Insulin And Insulin-Mimetics On Mrna Levels Of C-Fos And C-Jun In Primary Rat Hepatocytes In Culture, Guangmin Li

Masters Theses

Insulin is capable of regulating cellular and metabolic processes as well as gene expression. Selenate and vanadate are two compounds that have been found to mimic the action of insulin in several tissue and cell types. cFos and cJun are the products of immediate early responsive genes c-fos and c-jun. They are members of the family of the AP-1 (Activator Protein-1) transcription factors. AP-1 transcription factors bind as cJun.cJun homodimer or cJun.cFos heterodimer to the TRE found in the promoter regions of several genes. AP-1 is characterized by its ability to alter gene expression in response to various peptide …


Effects Of High-Molecular-Weight Dissolved Organic Matter On Nitrogen Dynamics In The Mississippi River Plume, Wayne S. Gardner, Ronald Benner, Rainer M.W. Amon, James B. Cotner Jr., Joann F. Cavaletto, Jeffrey R. Johnson Mar 1996

Effects Of High-Molecular-Weight Dissolved Organic Matter On Nitrogen Dynamics In The Mississippi River Plume, Wayne S. Gardner, Ronald Benner, Rainer M.W. Amon, James B. Cotner Jr., Joann F. Cavaletto, Jeffrey R. Johnson

Faculty Publications

The dynamics of N and its interactions with labile dissolved organic C (DOC), bacteria, and phytoplankton were studied to determine potential effects of dissolved organic matter (DOM) and light on N dynamics in surface waters of the Mississippi River (USA) plume in the Gulf of Mexico. Bacterial uptake of added labeled N compounds ( 15NH4+ or 15N-labeled dissolved free amino acids. DFAA) was stimulated more by high-molecular-weight (HMW, >l kDa) DOM than by low-molecular-weight (LMW, < l kDa) DOM. An index that inversely indicated the presence of labile DOC was defined as the fraction of assimilated Amino acid-15N that was Recovered as 15N -Ammonium (ANRA), following the additions of high-levels (4 µM) of 15N -DFAA. …


Use Of The (3)H-Tetracycline Rat Model In The Study Of Skeletal Compartmentalization And Metabolism Of Calcium In The Maturing Male And Female Rat And The Role Of The Skeleton In Calcium Homeostasis In The Adolescent Male Rat, Darrin Lee Demoss Jan 1996

Use Of The (3)H-Tetracycline Rat Model In The Study Of Skeletal Compartmentalization And Metabolism Of Calcium In The Maturing Male And Female Rat And The Role Of The Skeleton In Calcium Homeostasis In The Adolescent Male Rat, Darrin Lee Demoss

Theses, Dissertations and Capstones

The (3)H-tetracycline bone labeling procedure was employed to monitor bone resorption from urinary loss curves in male and female rats of various ages. In addition, whole body dry skeletal mass and the loss of (3)H-tetracycline from individual bones was determined. It was found that the dry skeletal mass/body mass ratio of 24-week-old females was 30-40% greater than that for males. The urinary loss of (3)H-tetracycline was described by a double exponential equation indicating the presence of two distinct and independent exchangeable bone compartments. Both compartments decrease in size with age, but their label loss activities were different. The label loss …


The Potential For Ontogenetic Vertical Migration By Larvae Of Bathyal Echinoderms, William Jaeckle, Craig M. Young, Michael G. Devin, Suki U.K. Ekaratne, Sophie B. George Jan 1996

The Potential For Ontogenetic Vertical Migration By Larvae Of Bathyal Echinoderms, William Jaeckle, Craig M. Young, Michael G. Devin, Suki U.K. Ekaratne, Sophie B. George

Scholarship

Planktotrophy is a relatively common developmental mode among bathyal and abyssal echinoderms, but the sources of food used by deep-sea planktotrophic larvae remain generally unknown. Very few deep-sea echinoderm larvae have been collected in plankton samples, so we do not know whether larvae migrate to the euphotic zone to feed or if they rely on bacteria or detritus at greater depths. We approached this question indirectly by investigating whether larvae of bathyal echinoids can tolerate the temperatures they would encounter in the euphotic zone and whether they possess sufficient energy stores to migrate to the euphotic zone without feeding. Twenty-four …


Communities Of Cloacal Bacteria In Tree Swallow Families, Michael P. Lombardo, Patrick A. Thorpe, R. Cichewicz, M. Henshaw, C. Millard, C. Steen, T. K. Zeller Jan 1996

Communities Of Cloacal Bacteria In Tree Swallow Families, Michael P. Lombardo, Patrick A. Thorpe, R. Cichewicz, M. Henshaw, C. Millard, C. Steen, T. K. Zeller

Peer Reviewed Publications

Our aim in this study was to survey the communities of bacteria found in the cloacae of adult and nestling Tree Swallows (Tachycineta bicolor), determine if there were familial patterns of prevalence, and determine if there were relationships between bacteria loads and nestling size when 12 days old and fledging success.


Fate Of Biological Control Introductions: Monitoring An Australian Fungal Pathogen Of Grasshoppers In North America, Michael J. Bidochka, Scott R. A. Walsh, Mark E. Ramos, Raymond J. St. Leger, Julie Cl Silver, Donald W. Roberts Jan 1996

Fate Of Biological Control Introductions: Monitoring An Australian Fungal Pathogen Of Grasshoppers In North America, Michael J. Bidochka, Scott R. A. Walsh, Mark E. Ramos, Raymond J. St. Leger, Julie Cl Silver, Donald W. Roberts

Biology Faculty Publications

In North America there are two generally recognized pathotypes (pathotypes 1 and 2) of the fungus Entomophaga grylli which show host-preferential infection of grasshopper subfamilies. Pathotype 3, discovered in Austra- lia,hasabroadergrasshopperhostrangeandwasconsidered to be a good biocontrol agent. Between 1989 and 1991 patho- type3wasintroducedattwofieldsitesinNorthDakota.Since resting spores are morphologically indistinguishable among pathotypes, we used pathotype-specific DNA probes to con- firm pathotype identification in E. grylli-infected grasshop- pers collected at the release sites in 1992, 1993, and 1994. In 1992, up to 23% of E. grylli-infected grasshoppers of the subfamilies Melanoplinae, Oedipodinae, and Gomphocerinae were infected by pathotype 3,with no infections >1 km …


Development Of A New Hydroseeding Process For Soil Stabilisation And Vegetation, Eileen T. Keane Jan 1996

Development Of A New Hydroseeding Process For Soil Stabilisation And Vegetation, Eileen T. Keane

Theses

A variety of mechanical and chemical extraction procedures were used to produce crude alginate gels from 3 seaweed species. These viscous hydrocolloidal substances had excellent adhesive properties but did however prove phytotoxic to germinating seeds. Experimental gels were subsequently refined and germination trials were carried out to determine optimum gel types. Pilot field trials were set up to compare the 2 most favourable gels with existing commercial hydroseeding products imported from Norway and Sweden. These tests involved the use of experimental plots on loam and sand substrates with slopes of 0^, 22^ and 45^. A number of biodegradable organic substances …


Channel Catfish, Ictalurus Punctatus, T-Lymphocyte Mitogenic Responses To Outer Membrane Proteins And Lps Of The Gram Negative Rod Bacterium, Edwardsiella Ictaluri, Barry Revis Hamilton Dec 1995

Channel Catfish, Ictalurus Punctatus, T-Lymphocyte Mitogenic Responses To Outer Membrane Proteins And Lps Of The Gram Negative Rod Bacterium, Edwardsiella Ictaluri, Barry Revis Hamilton

Morehead State Theses and Dissertations

A thesis presented to the faculty of the Department of Biological and Environmental Sciences at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Barry Revis Hamilton on December 8, 1995.


Feeding And Nesting Ecology Of The Great Kiskadee, Pitangus Sulphuratus Texanus (Passeriformes: Tyrannidae) In The Lower Rio Grande Valley, Texas, Robert Luis Gorena Dec 1995

Feeding And Nesting Ecology Of The Great Kiskadee, Pitangus Sulphuratus Texanus (Passeriformes: Tyrannidae) In The Lower Rio Grande Valley, Texas, Robert Luis Gorena

Theses and Dissertations - UTB/UTPA

The foraging and nesting ecology of the Great Kiskadee was studied in the Lower Rio Grande Valley, Texas during 1994 and 1995. Adult kiskadees were found to be omnivorous, feeding mainly on fleshy fruits, fish, and dragonflies, and capturing animal prey mainly by surface gleaning into water or hawking prey out of midair. Nests are constructed mainly during March and April and are built at heights between 6 and 10 meters apparently without preference to tree species. Of 29 nests observed, 66% (19) were active during at least part of the breeding season. Nestlings are fed a diet very similar …


In Vivo Metal Substitutions In Metal Sequestering Subcellular Compartments: X-Ray Mapping In Cryosections, A. J. Morgan, C. Winters, A. Yarwood, N. Wilkinson Nov 1995

In Vivo Metal Substitutions In Metal Sequestering Subcellular Compartments: X-Ray Mapping In Cryosections, A. J. Morgan, C. Winters, A. Yarwood, N. Wilkinson

Scanning Microscopy

Qualitative digital X-ray mapping techniques were employed to determine the distributions of essential and non-essential elements in three invertebrate "models": (1) Pb, Zn, Cd, Cu, Fe in thin cryosections of the hepatopancreas of the terrestrial isopod, Oniscus asellus; (2) Pb, Zn, Cd, Ca in thin cryosections of the chloragogenous tissue of the earthworm, Lumbricus rubellus; and (3) As in air-dried smears and thin cryosections of chloragogen in L. rubellus. Four general conclusions were drawn from the results of these studies: (a) non-essential elements can accumulate, distribute and be compartmentalized because they, or the organo-complexes that they form, …


Zinc Deficiency Produces Time-Related Ultrastructural Changes In Rat Cheek Epithelium, Shahid H. Ashrafi, Nasser A. H. Said-Al-Naief Nov 1995

Zinc Deficiency Produces Time-Related Ultrastructural Changes In Rat Cheek Epithelium, Shahid H. Ashrafi, Nasser A. H. Said-Al-Naief

Scanning Microscopy

The subject of this study was whether the ultrastructural changes in cheek epithelium of zinc-deficient rats are time related. Weanling male Sprague Dawley rats were fed a zinc-deficient diet containing 0.4 ppm zinc (ZD) ad libitum and controls were pair-fed zinc adequate diet containing 40 ppm zinc. After 9, 18, and 27 days of zinc deficiency, specimens from cheek epithelium of both groups were processed for transmission electron microscopy. Partial conversion of the orthokeratinized cheek epithelium to parakeratinized was seen as early 9 days. An electron-lucent band surrounding the nucleus was observed in ZD cells. Mitochondria, tonofilaments, keratohyalin granules and …


Alterations In Intestinal Transport Of Oxalate In Disease States, Marguerite Hatch, Robert W. Freel Nov 1995

Alterations In Intestinal Transport Of Oxalate In Disease States, Marguerite Hatch, Robert W. Freel

Scanning Microscopy

Normally, absorption of oxalate from dietary sources can occur in all segments of the intestinal tract. However, alterations in both the magnitude and direction of oxalate fluxes across the intestine can occur in disease states. In enteric hyperoxaluria, enhanced absorption of oxalate by the large intestine is caused by increased permeability of a shunt conductance induced by malabsorbed bile salts and fatty acids. In this condition, the contribution of a paracellular passive flux of oxalate moving along its electrochemical gradient will predominate when intraluminal concentrations of free oxalate are high. In contrast, in chronic renal failure, secretion of oxalate can …


Dietary Oxalate And Its Intestinal Absorption, Ross P. Holmes, Harold O. Goodman, Dean G. Assimos Oct 1995

Dietary Oxalate And Its Intestinal Absorption, Ross P. Holmes, Harold O. Goodman, Dean G. Assimos

Scanning Microscopy

Dietary oxalate is currently believed to make only a minor contribution (< 20%) to urinary oxalate excretion. A recent prospective study of stone disease suggested that dietary oxalate may be a significant risk factor. This observation led us to re-evaluate the contribution of dietary oxalate to urinary oxalate excretion. Previous studies have been hampered by inaccurate food composition tables for oxalate and inadequate methods for studying intestinal oxalate absorption. This evidence as well as factors that modify oxalate absorption are reviewed. New approaches to measure food oxalate and intestinal oxalate absorption have been examined. Capillary electrophoresis appears to be well suited for the analysis of the oxalate content of food. Two individuals consumed an oxalate-free formula diet for 7 days. This diet decreased urinary oxalate excretion by an average of 67% (18.6 mg per 24 hours) compared to oxalate excretion on self-selected diets. The absence of detectable oxalate in feces by day 6 of the diet suggested that the intestinal absorption was minimal. However, an effect of the formula diet on endogenous oxalate synthesis cannot be excluded. Restoring oxalate to the formula diet increased urinary oxalate excretion and illustrates that this experimental protocol may be well-suited for studying oxalate absorption and factors that modify it. Our results suggest that the intestinal absorption of dietary oxalate makes a substantial contribution to urinary oxalate excretion and that this absorption can be modified by decreasing oxalate intake or increasing the intakes of calcium, magnesium, and fiber.


Microvascular Corrosion Casting In The Study Of Tumor Vascularity: A Review, M. A. Konerding, A. J. Miodonski, A. Lametschwandtner Sep 1995

Microvascular Corrosion Casting In The Study Of Tumor Vascularity: A Review, M. A. Konerding, A. J. Miodonski, A. Lametschwandtner

Scanning Microscopy

Tumor blood flow is dependent on the structure and three-dimensional (3-D) architecture of the vascular network. The latter can be best studied by scanning electron microscopy of microvascular corrosion casts. However, literature reviews show that nearly all studies using this technique render comparisons of different tumors more difficult since they are mainly based on descriptive terms that might lead to misunderstandings. Qualitative comparisons of 13 experimental and 3 human primary tumors of different origin show a high degree of similarity in the vasculature. Quantitative analysis of these casts reveals similar ranges of parameters such as diameters, intervascular and interbranching distances. …


Apoptosis And Calcification, Kookmin M. Kim Sep 1995

Apoptosis And Calcification, Kookmin M. Kim

Scanning Microscopy

Calcification in necrosis has long been known. Of the tissue components, the cells are most vulnerable. Nevertheless, little attention has been paid to the role of cell death in calcification. This review attempts to update the mechanism of calcification with an emphasis on the role of apoptosis in calcification. A brief review on the basic sciences relevant to calcification is followed by a discussion of abnormal Ca2+ and Pi homeostasis in cell injury and apoptosis. Concomitant increases in Ca2+ and Pi in blebs (and matrix vesicles) formed by apoptotic and/or necrotic cells are apparently the primary …


Low Temperature Techniques As A Tool In Plant Pathology, Sigrun Hippe-Sanwald Sep 1995

Low Temperature Techniques As A Tool In Plant Pathology, Sigrun Hippe-Sanwald

Scanning Microscopy

In plant pathology, low temperature preparation techniques now appear to be feasible methods to stabilize the dynamic ultrastructure of the host-(plant)-pathogen (fungi) interaction for an analysis by transmission electron microscopy. A well defined ultrastructure of small organisms (fungi) and large biological samples such as plant material and as well as the plant-pathogen (fungus) infection sites are presented. The mesophyll tissue of Arabidopsis thaliana is characterized by homogeneously structured cytoplasm closely attached to the cell wall. Infection sites of stem rust (Puccinia graminis f. sp. tritici) on primary leaves of wheat (Triticum aestivum) and powdery mildew (Erysiphe …


Vitamin B6 Deficiency And Galactose Induced Alterations In Morphology And Osmotic Fragility Of Rat Erythrocytes, P. Kaul, H. Sidhu, S. K. Thind, S. K. Sharma, R. Nath Aug 1995

Vitamin B6 Deficiency And Galactose Induced Alterations In Morphology And Osmotic Fragility Of Rat Erythrocytes, P. Kaul, H. Sidhu, S. K. Thind, S. K. Sharma, R. Nath

Scanning Microscopy

Recently, red blood cells have been investigated mainly for alterations in ion transporting capacity, membrane bound enzymes or modifications in the structure of its individual constituents in clinical and experimental urolithiasis. However, the implication of such modifications on the physical state or morphology of cells has not been investigated. Scanning electron microscopic studies performed in vitamin B6 deficient and/or galactose fed rat (established hyperoxaluric models) erythrocytes, showed the presence of large number of stomatocytes, spherocytes and other variously deformed cells as compared to discocytic cells seen in normal control group. These changes in shape were in concurrence with red …


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 Jun 1995

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 …