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The Application Of Physico-Chemical Procedures In The Analysis Of Urinary Calculi, Allen L. Rodgers Jun 1985

The Application Of Physico-Chemical Procedures In The Analysis Of Urinary Calculi, Allen L. Rodgers

Scanning Electron Microscopy

All physico-chemical techniques used in the analysis of urinary calculi have inherent advantages and limitations. Al though x-ray powder diffraction can identify constituents unambiguously, certain minor components can be missed. Infrared spectroscopy is more sensitive but band assignment at low concentrations is difficult. Scanning electron microscopy together with energy dispersive x-ray analysis permits the simultaneous investigation of morphology and chemical microstructure. However, microanalysis of elements lighter than sodium is not possible and constituents are prone to irradiation damage. With the electron microprobe, minor constituents can be detected but tedious sample preparation procedures are required. Transmission electron microscopy is extremely useful …


Microbial Degradation Of The Leachable And Lignocellulosic Components Of Leaves And Wood From Rhizophora Mangle In A Tropical Mangrove Swamp, Ronald Benner, Robert E. Hodson May 1985

Microbial Degradation Of The Leachable And Lignocellulosic Components Of Leaves And Wood From Rhizophora Mangle In A Tropical Mangrove Swamp, Ronald Benner, Robert E. Hodson

Faculty Publications

Preparations of uniformly [14C] labeled mangrove leaves and specifically radiolabeled [14C-lignin] lignocelluloses and [14C -polysaccharide]lignocelluloses from mangrove leaves and wood were used in experiments to determine the microbial rates of mineralization of the leachable and lignocellulosic components of mangrove detritus in aerobic and anaerobic sediments of a tropical mangrove swamp. The bulk of the leachable fraction from mangrove leaves was mineralized relatively rapidly and was assimilated into microbial biomass with high efficiency (30 %). In contrast, rates of mineralization of the lignocellulosic component of mangrove leaves and wood were 10fold lower than mineralization rates …


Calcium Oxalate Urolithiasis In The Rat: Is It A Model For Human Stone Disease? A Review Of Recent Literature, S. R. Khan, R. L. Hackett May 1985

Calcium Oxalate Urolithiasis In The Rat: Is It A Model For Human Stone Disease? A Review Of Recent Literature, S. R. Khan, R. L. Hackett

Scanning Electron Microscopy

Calcium oxalate stone disease is the most common human urinary stone disease in the Western Hemisphere. To understand different aspects of the disease, calcium oxalate urolithiasis in the rat is used as a model. Spontaneous calcium oxalate urolithiasis is very rare in rats. Thus the disease is experimentally induced and the rats are generally made hyperoxaluric either by administration of excess oxalate, exposure to the toxin ethylene glycol, or various nutritional manipulations. All the experimental models show renal injury associated with crystal deposition. Calcium oxalate crystals are in most cases intraluminal in renal tubules and often attached to the basal …


Relationship Between Glucose-6-Phosphate Dehydrogenase Activity And Hormone Dependency In Rat Mammary Cancer, Lila S. Berry May 1985

Relationship Between Glucose-6-Phosphate Dehydrogenase Activity And Hormone Dependency In Rat Mammary Cancer, Lila S. Berry

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 Lila S. Berry on May 2, 1985.


Structure And Surface Exposure Of Protein-Iis Of Neisseria-Gonorrhoeae Js3, Ralph C. Judd May 1985

Structure And Surface Exposure Of Protein-Iis Of Neisseria-Gonorrhoeae Js3, Ralph C. Judd

Biological Sciences Faculty Publications

Colonies of Neisseria gonorrhoeae JS3, each bearing a predominate protein II (PII) type, were derived from a progenitor transparent colony. Five distinct PIIs were identified and isolated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The PII bands were excised from gels of unlabeled whole cells and from gels containing lysates of surface-radioiodinated bacteria. These were subjected to alpha-chymotrypsin digestion and two-dimensional peptide mapping, which allowed for a comparison of both the primary structures of the PIIs and the identification of surface-exposed regions of the molecules. The results demonstrated that PIIs are unrelated to either Protein I or Protein III in structure …


Cellular Immunity In Children With Down Syndrome (Trisomy-21), Roger Lee Noble May 1985

Cellular Immunity In Children With Down Syndrome (Trisomy-21), Roger Lee Noble

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Individuals with Down syndrome (US) suffer from increased incidence of respiratory infections and lymphoblastic leukemia, and a death rate that is particularly high in the first 5 years of life. Relatively few studies have probed immune parameters in young US children. Primary immune defects in DS may be masked by a degree of immune maturity in adults, and hygienic factors may have an effect on immune capability throughout the years. A study of young children can give clearer evidence of the actual primary immune defects in DS.

Blood samples were drawn from 20 DS children under 6 years old and …


Energetics Of The American Kestrel (Falco Sparverius) During Three Seasons In Northern Utah, Lucinda Haggas May 1985

Energetics Of The American Kestrel (Falco Sparverius) During Three Seasons In Northern Utah, Lucinda Haggas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Behavioral activities and predatory behavior of 18 American Kestrels (Falco sparverius, 9 males and 9 females) were observed for 350+ hours during 3 seasons (nonbreeding = Jan-Feb , breeding = mid-Mar-Apr, and postbreeding = late-Aug-Sept) in northern Utah. Daily energy expenditure (DEE) of male and female kestrels was estimated with a model that incorporated flight activity data from free-living birds and laboratory measurements on daytime and nighttime metabolic rates and energy costs of tissue production derived from captive kestrels. Production costs were included in the DEE for breeding and postbreeding kestrels.

The energy cost of gonadal growth for males (0.02 …


Production Of Monoclonal Antibodies Specific For The Microgametocytes Of Eimeria Tenella, Marc A. Laxer May 1985

Production Of Monoclonal Antibodies Specific For The Microgametocytes Of Eimeria Tenella, Marc A. Laxer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this study was to produce a monoclonal antibody specific for the microgametocytes of Eimeria tenella, examine the site and stage specificity of the antibody, and investigate the immunopotency of the antibody. BALB/c mice were immunized with antigen containing Eimeria tenella microgametocytes isolated from in vitro systems. After three intraperitoneal immunizations with the antigen and one booster immunization administered by tail vein injection, the mice were sacrificed and their spleen cells fused with SP2/0 mouse myeloma cells using polyethylene glycol as a fusing agent. Resultant hybridomas were screened by immunoelectrophoresis, indirect immunofluorescent antibody assay, and immunoelectron microscopy …


Structural Changes In Mouse Small Intestinal Villi Following Lower Body Hyperthermia, H. M. H. Kamel, K. E. Carr, S. P. Hume, J. C. L. Marigold Apr 1985

Structural Changes In Mouse Small Intestinal Villi Following Lower Body Hyperthermia, H. M. H. Kamel, K. E. Carr, S. P. Hume, J. C. L. Marigold

Scanning Electron Microscopy

Heating an exteriorised loop of mouse small intestine resulted in marked changes in the shape of the villi as reported earlier. However, the exteriorisation techniques resulted in non-uniformity in both temperature and effect around circumference of intestine and, in addition, the extent to which handling contributed to the observed damage was not known. The work has therefore been extended using lower-body heating in the temperature range 37.5° - 43.0°C.

Heating in the temperature range 37.5° to 41.0°C produced minimal to moderate structural changes, manifested as scattered, vertically collapsed villi amongst predominantly "normal" villi. No villi showed conical or rudimentary forms …


Integration Of X-Ray Microanalysis And Morphometry Of Biological Material, W. C. De Bruijn Apr 1985

Integration Of X-Ray Microanalysis And Morphometry Of Biological Material, W. C. De Bruijn

Scanning Electron Microscopy

It was investigated how to extract both morphometrical and X-ray elemental information from scanning electron microscopical (SEM) or scanning transmission electron microscopical (STEM)-images and how to integrate these two information streams either on line or off-line after storage.

Cytochemical reaction products in cell organelles in ultrathin sections are the biological structures of interest. In such organelles four different situations can be met: morphologically the structures are homomorph or heteromorph; chemically the elements are distributed either homogeneously or heterogeneously. A new program has been proposed and described, which permits determination of both the area and the mean net-intensity value of chemical …


Histochemical And Physiological Characteristics Of The Rat Diaphragm, Joseph Mark Metzger, K. B. Scheidt, Robert H. Fitts Apr 1985

Histochemical And Physiological Characteristics Of The Rat Diaphragm, Joseph Mark Metzger, K. B. Scheidt, Robert H. Fitts

Biological Sciences Faculty Research and Publications

The histochemical and contractile characteristics of the adult rat diaphragm were determined. Based on enzyme histochemistry, the rat diaphragm contained 40% type I, 27% type IIa, and 34% type IIb fibers. There were significantly more type I fibers in the ventral costal (VEN) compared with the crural (CRU) region of the muscle and a slightly higher percentage of type I's on the thoracic relative to the abdominal surface. The contractile properties and the effect of temperature (Q10) were similar in the VEN and CRU regions. Increasing temperature produced higher isometric peak tetanic tension, whereas twitch tension, contraction, and …


X-Ray Microanalysis Of Biological Tissues - An Examination Of Comparative Specimen Preparation Techniques Using Prostatic Tissue As A Model, J. A. Chandler Mar 1985

X-Ray Microanalysis Of Biological Tissues - An Examination Of Comparative Specimen Preparation Techniques Using Prostatic Tissue As A Model, J. A. Chandler

Scanning Electron Microscopy

A number of reproductive tissues have been investigated by X-ray microanalysis for a large number of elements. These elements occur both free and with many different forms of binding to tissue proteins and cellular constituents. The prostate tissue studied here represents a glandular tissue with both parenchymal and stromal components having different cell types. While no general rule can be applied to the preparative technique for all tissues, it would seem that of all the methods examined here freeze substitution or the use of dehydration fluids combined with subsequent embedding offer the most promising compromise between cryoultramicrotomy and aqueous fixation.


Limits Of Quantitative Microanalysis Using Secondary Ion Mass Spectrometry, Peter Williams Feb 1985

Limits Of Quantitative Microanalysis Using Secondary Ion Mass Spectrometry, Peter Williams

Scanning Electron Microscopy

The limitations on secondary ion micro-analytical performance imposed by ionization probabilities, mass spectrometer transmission, requirements for standards and sputtering artifacts have been investigated. The sensitivity of a modern magnetic mass spectrometer for sputtered B+ from oxidized Si is ~ 10-2 ions detected/atom sputtered. For this sensitivity, it is shown that ion microscopy of a part-per-million impurity is limited in lateral resolution to ~ 1 μm. For a 1% impurity, lateral resolution of ~ 30 nm is achievable. Depth profile analysis at the ppm level requires sample areas ~ 10 μm2. Isotope abundance determinations in volumes ~ …


Freeze-Drying And Related Preparation Techniques For Biological Microprobe Analysis, Romuald Wróblewski, Joanna Wróblewski, Matti Anniko, Lars Edström Jan 1985

Freeze-Drying And Related Preparation Techniques For Biological Microprobe Analysis, Romuald Wróblewski, Joanna Wróblewski, Matti Anniko, Lars Edström

Scanning Electron Microscopy

An X-ray microanalytical and morphological investigation has been carried out on rapidly frozen, freeze-dried or freeze-substituted tissues. A comparison was made between different embedding and polymerisation procedures following freeze-substitution and freeze-drying. The investigation also included an analysis of specimens infiltrated, embedded and polymerised by ultraviolet irradiation at low temperatures with Lowicryl HM20. The morphological preservation of Lowicryl embedded tissue was adequate for the identification of different cell structures like nuclei, mitochondria, lysosomes and different types of endoplasmic reticulum. X-ray microanalytical investigation of low temperature embedded material displayed an elemental composition of cells and organelles similar to that found in freeze-dried …


Applications Of Scanning Electron Microscopy And X-Ray Microanalysis In Inner Ear Pathology, M. Anniko, D. J. Lim, A. Sobin, R. Wróblewski Jan 1985

Applications Of Scanning Electron Microscopy And X-Ray Microanalysis In Inner Ear Pathology, M. Anniko, D. J. Lim, A. Sobin, R. Wróblewski

Scanning Electron Microscopy

Surface pathology of inner ear structures so far described in detail concern cochlear and vestibular hair cells and the stria vascularis. In man, surgical intervention into the inner ear is very uncommon and when performed is in general with the primary objective of destroying the diseased peripheral end organs. The vast majority of inner ear tissue available for use with scanning electron microscopy (SEM) is therefore obtained from animals.

The present paper reviews the progression of surface pathology caused by aminoglycoside antibiotics, acoustic overstimulation and in a guinea pig strain with genetic inner ear disease. The primary site of onset …


Ultrastructural Studies Of Crystal-Organic Matrix Relations In Renal Stones, P. -T. Cheng, A. D. Reid, K. P. H. Pritzker Jan 1985

Ultrastructural Studies Of Crystal-Organic Matrix Relations In Renal Stones, P. -T. Cheng, A. D. Reid, K. P. H. Pritzker

Scanning Electron Microscopy

Biochemically the organic matrix of kidney stones contains mucoproteins, mucopolysaccharides, inorganic material and bound water. Morphologically, the organic matrix exists as either amorphous or fibrous forms. We have attempted to critically evaluate results from analytical and morphological studies on stone matrices using light microscopy, histochemistry, x-ray diffraction, scanning electron microscopy, x-ray energy dispersive spectrometry, transmission electron microscopy and selected area electron diffraction.

On the surface of calcium oxalate stones, there are usually large masses of randomly deposited calcium oxalate crystals each coated with organic matrix. Transmission electron microscopy shows these large surface crystals are composed of rows of smaller crystallites …


In Vivo Light Microscopy Of Organs, Robert S. Mccuskey Jan 1985

In Vivo Light Microscopy Of Organs, Robert S. Mccuskey

Scanning Electron Microscopy

High resolution, brightfield and fluorescence, light microscopic methods have been developed for examining living organs in situ. The methods permit study of the rate, duration, magnitude and direction of dynamic histologic, pathologic, physiologic and pharmacologic events. In addition, morphometric analyses of such living preparations can provide basic information needed to evaluate alterations induced by fixation and processing of these organs for electron microscopy. Most organs are amenable to such investigations. In anesthetized animals, the selected organ is trans-and/or epi-illuminated with selected wavelengths of monochromatic light, imaged with water immersion objectives and the resulting monochromatic optical images televised using silicon …


On The Application And Possibilities Of In Vivo Microscopy In Liver Research, E. Wisse, R. S. Mccuskey Jan 1985

On The Application And Possibilities Of In Vivo Microscopy In Liver Research, E. Wisse, R. S. Mccuskey

Scanning Electron Microscopy

In vivo microscopy (IVM) provides a valuable method for studying the histophysiology of the living liver. The method allows observation of living cells in the intact organ of an anesthetized animal with an undisturbed microcirculation, at a magnification and a resolution comparable to normal light microscopy of sectioned material. Due to the absence of preparative procedures, the image differs substantially from histological sections, but it has the advantage of providing us with a reference preparation free of artifacts. In the case of the liver, we have the opportunity to observe directly such details as bile capillaries, intracellular fat droplets, lysosomes, …


Tandem Scanning Reflected Light Microscopy, Mojmir Petran, Milan Hadravsky, Alan Boyde, Martin Mueller Jan 1985

Tandem Scanning Reflected Light Microscopy, Mojmir Petran, Milan Hadravsky, Alan Boyde, Martin Mueller

Scanning Electron Microscopy

Most attempts at optical microscopy of bulk living objects have failed because of reflections from optical components and the object surface, and overlapping of unsharp out-of-focus images with the one (weak) sharp in-focus image. The optical signal in the image plane thus consists of a strong d.c. component, a weak noise and a still weaker signal. Most of the first two components can be suppressed by scanning in concordance with both the illuminating and the image-forming rays. In the first scan the focussed-on-object plane is illuminated only in several very fine discrete spots. In the second scan only that light …


Effects Of Temperature And Crowding On The Pathogenicity Of Edwardsiella Ictaluri In Channel Catfish (Ictalurus Punctatus), Sharon L. Johnson, Lawrence W. Hinck Jan 1985

Effects Of Temperature And Crowding On The Pathogenicity Of Edwardsiella Ictaluri In Channel Catfish (Ictalurus Punctatus), Sharon L. Johnson, Lawrence W. Hinck

Journal of the Arkansas Academy of Science

Channel catfish were injected with Edwardsiella ictaluri and stocked at increasing temperatures and densities. Bacteriological examination of kidney, liver and spleen revealed the greatest numbers of organisms in fish from the highest temperature and stocking density tested. Survival time was the shortest for fish held at the highest temperature and stocking density. Increased temperature and crowding were directly proportional to the number of organisms recovered from the organs and inversely proportional to fish survival time.


Biotic Interactions Among Estuarine Infaunal Opportunistic Species, Roman Zajac, R. B. Whitlatch Jan 1985

Biotic Interactions Among Estuarine Infaunal Opportunistic Species, Roman Zajac, R. B. Whitlatch

Biology and Environmental Science Faculty Publications

Biotic interactions among soft-sediment infauna were investigated in a small New England estuary in order to determine what effect(s) established opportunistic species had on subsequent recolonization. Interactions were defined according to successional models developed by Connell and Slatyer (1977), e.g. facilitation, tolerance and inhibition. Adults of the opportunistic polychaetes Streblospio benedicti, Polydora ligni and Hobsonia florida were added at 2 densities to separate cores containing defaunated sediment. These cores and control cores containing no worms were sampled at 10 d intervals for 40 d. Cores containing capillary tubes to simulate polychaete tubes were also deployed and sampled at 10 d …


Concanavalin A-Binding Enzymes Of Crotalus Scutulatus Scutulatus Venom, Michael W. Hinson, C. K. Childs, Bob D. Johnson, Dewey H. Sifford Jan 1985

Concanavalin A-Binding Enzymes Of Crotalus Scutulatus Scutulatus Venom, Michael W. Hinson, C. K. Childs, Bob D. Johnson, Dewey H. Sifford

Journal of the Arkansas Academy of Science

Crotalus scutulatus scutulatus crude venom was separated into two fractions by Concanavalin A Sepharose 4B affinity chromatography. The proteins binding to Con A exhibited phosphomonoesterase (orthophosphoric monoester phosphohydrolase EC 3.1.3.2), phosphodiesterase, 5'-nucleotidase (5'-ribonucleotide phosphohydrolase EC 3.1.3.5), phospholipase A(phosphatidate 2-acylhydrolase EC 3.1.1 .4), hyaluronidase (hyaluronate glycanohydrolase EC 3.2.1 d), N-benzoyl-L-arginine ethyl esterase, p-toluenesulfonyl-L-arginine methyl esterase, L-amino acid oxidase (L-amino acid: 02 oxidoreductase [deaminating] EC 1.4.3.2), and caseinolytic activities. Thrombin-like and NAD nucleosidase (5'-ribonucleotide phosphohydrolase EC 3.1.3.5) activities were not observed. The crude venom and the fraction containing the glycoproteins which bound to Con A were fractionated by DEAE Sephadex A-50 ion …


The State Of Water In The Cell, William Negendank Jan 1985

The State Of Water In The Cell, William Negendank

Scanning Electron Microscopy

A number of scientists in the early 20th century conceived cell water and ions as existing in unique "colloidal" or "bound" states. Work in the 1930's, however, established the assumption that most of cell water and of K exist in a free state like that of a dilute aqueous solution, so that the osmotic activity of cell K serves to balance that of the high concentration of extracellular Na. This assumption underlies theoretical concepts of membrane pumps, Donnan equilibria, and cell potentials, and led to the now classical membrane-osmotic-pump-leak concept of cell ionic distributions and volume maintenance. Nevertheless, the results …


Demonstrable Fixative Interactions, Keith M. Meek, John A. Chapman Jan 1985

Demonstrable Fixative Interactions, Keith M. Meek, John A. Chapman

Scanning Electron Microscopy

Electron-optical examination of reconstituted collagen fibrils fixed with tannic acid and/or glutaraldehyde and positively stained with heavy metal anions and cations reveals distinct changes in the high resolution staining patterns seen in TEM. Correlation with the known sequence data demonstrates that these changes are caused by (a) interaction of the fixative with certain charged groups in the collagen and (b) localized stain-exclusion effects following fixation. We have analysed the positive and negative staining patterns from glutaraldehyde-treated collagen in detail. In positive staining, uptake of staining ions is shown to be inhibited not only at residues known to interact with glutaraldehyde …


Cell Volume Regulation Studies With The Electron Microprobe, Mary Jo Ingram, F. Duane Ingram Jan 1985

Cell Volume Regulation Studies With The Electron Microprobe, Mary Jo Ingram, F. Duane Ingram

Scanning Electron Microscopy

Lumbricals from the hind feet of young rats are dissected free, stretched to approximately 125% of resting length, and mounted on individual, simple plastic forms. After recovery in physiological saline, the isolated muscles are incubated for periods of 40 to 60 min. in one of a series of hypertonic bathing solutions. The composition of each bathing solution is identical, except for osmolality which is increased with lactose. At least one muscle from each animal is incubated in a control solution to serve as a control muscle for that particular set of 5 to 8 muscles. Mounted muscles are removed from …


Two Opposing Theories Of The Cell: Experimental Testing By Cryomethods And Electron Microscopy, L. Edelmann Jan 1985

Two Opposing Theories Of The Cell: Experimental Testing By Cryomethods And Electron Microscopy, L. Edelmann

Scanning Electron Microscopy

A main controversial issue in cell biology concerns the molecular mechanism responsible for K+ accumulation in living cells and Na+ exclusion from them. The alternative theoretical descriptions of these phenomena are based on different assumptions about the physical state of cellular Na+, K+ and H2O. In this article it is shown with striated muscles how cryomethods and microanlytical electron microscopy may be used to test the opposing theories. It is concluded that these methods may yield more realistic informations about the physical state of cellular K+ and Na+ than measurements with …


Immunocytochemical Labeling Of Enzymes In Low Temperature Embedded Plant Tissue: The Precursor Of Glyoxysomal Malate Dehydrogenase Is Located In The Cytosol Of Watermelon Cotyledon Cells, C. Sautter Jan 1985

Immunocytochemical Labeling Of Enzymes In Low Temperature Embedded Plant Tissue: The Precursor Of Glyoxysomal Malate Dehydrogenase Is Located In The Cytosol Of Watermelon Cotyledon Cells, C. Sautter

Scanning Electron Microscopy

The Lowicryl-technique in combination with protein A gold was used in order to localize the precursor of glyoxysomal malate dehydrogenase in watermelon cotyledons. Preservation of the antigen was evaluated by a preembedding technique in isolated organelles. The glyoxysomal malate dehydrogenase was localized in tissue sections by a postembedding technique. Antigens of glyoxysomal malate dehydrogenase were found in the glyoxysomal matrix and in the cytosol, whereas the endoplasmic reticulum was completely free of labeling. Controls are presented by preimmunserum, by a serum against various proteins of the glyoxysomal membrane and by application of cycloheximide in order to inhibit translation at cytosolic …


Working At Higher Magnifications In Scanning Electron Microscopy With Secondary And Backscattered Electrons On Metal Coated Biological Specimens And Imaging Macromolecular Cell Membrane Structures, Klaus-Ruediger Peters Jan 1985

Working At Higher Magnifications In Scanning Electron Microscopy With Secondary And Backscattered Electrons On Metal Coated Biological Specimens And Imaging Macromolecular Cell Membrane Structures, Klaus-Ruediger Peters

Scanning Electron Microscopy

Membrane structures of macromolecular dimensions were imaged with high resolution secondary electron type I (SE-I) signal contrasts on metal coated biological specimens. The quality of the surface information was strongly dependent on the signal used for microscopy and on the properties of metal films, i.e., thickness, continuity, structure and decoration effects. Films of 10 nm thickness produced so much type II electrons that identical images were obtained with the conventional SE-II and BSE-II signals. In such images, the type I SE signal was so low that only very weak contrasts were recognizable. If the films - continuous or discontinuous - …


Preparation Of Cryosections For Biological Microanalysis, Karl Zierold Jan 1985

Preparation Of Cryosections For Biological Microanalysis, Karl Zierold

Scanning Electron Microscopy

The element distribution in biological cells and tissues can be revealed by electron probe microanalysis from ultrathin cryosections. In particular, the distribution of physiologically important and often mobile elements such as Na, Mg, P, S, Cl, K, and Ca can be studied in cryosections on an ultrastructural level. The cryopreparation technique required for this purpose consists of 1. cryofixation, 2. cryosectioning, 3. cryotransfer including freeze-drying and carbon coating if necessary, 4. energy dispersive X-ray microanalysis in a cold stage equipped scanning transmission electron microscope. The lateral analytical resolution of this method is less than 50 nm in freeze-dried ultrathin (about …


Problems Associated With The Preparation Of Cell Suspensions For X-Ray Microanalysis Highlighted By The Comparison Of Results With Those Obtained From Tissue Sections, A. Warley, M. D. Kendall, I. W. Morris Jan 1985

Problems Associated With The Preparation Of Cell Suspensions For X-Ray Microanalysis Highlighted By The Comparison Of Results With Those Obtained From Tissue Sections, A. Warley, M. D. Kendall, I. W. Morris

Scanning Electron Microscopy

Fully quantitative X-ray microanalysis of freeze dried frozen sections allowed the concentration of monovalent ions in the nuclei of mouse thymocytes in tissue sections to be compared with those from thymocytes which had been isolated by a simple preparation procedure. Isolated cells showed increased concentrations of Na and Cl. This was further investigated in the rat where the size of the thymus a 11 owed comparison between different isolation media using cells derived from the same animal. Use of autologous serum as the final suspending medium gave reproducible results, whereas with suspension in BSS, or 20% dextran the results were …