Life Sciences Commons^™

The Secondary Blood Vessel System Of Segmental Arteries And Dorsal Aorta In Blennius Pavo And Zosterisessor Ophiocephalus. Histology, Fine Structure And Sem Of Vascular Corrosion Casts., F. Lahnsteiner, A. Lametschwandtner, R. A. Patzner

Scanning Microscopy

The secondary blood vessel system of the segmental arteries and of the dorsal aorta of the teleost fish Blennius pavo and Zosterisessor ophiocephalus are examined by light microscopy, transmission electron microscopy and by scanning electron microscopy of appropriately processed tissue and of vascular corrosion casts. Dorsal, lateral and ventral segmental arteries and the caudal portions of the dorsal aorta have a secondary vessel system. The secondary vessels are formed by capillaries which arise from the proximal portions of the segmental arteries and from the caudal parts of the dorsal aorta. In Z. ophiocephalus these capillaries are strongly dilated at their …

The Use Of Scanning Electron Microscopy In The Analysis Of Pathological Hairs, Bo Forslind

Scanning Microscopy

The potentials of the scanning electron microscope (SEM) have only to a certain degree been exploited in the study of pathological hair fibers. In this review brief viewpoints on aspects of preparation and interpretation are discussed. It is shown that SEM will reveal important facts on the morphology of pathological hairs is appropriate experiment are performed, such as forming a knot on the fiber. Such a simple experiment will provide information on the fiber cross section, and on the tensile strength of the cuticle and the fiber. Complementary methods for qualitative and quantitative analysis of pathological hair fibers are suggested.

Properties Of A New Dental Porcelain, T. K. Vaidyanathan, J. Vaidyanathan, A. Prasad

Scanning Microscopy

A high strength dental porcelain OPTEC, HSP™ has recently been introduced for use in the fabrication of crowns, three-unit anterior bridges with a single pontic, inlays, on lays, veneers, etc., without a metal substrate. This investigation reports the results of our research involving the characterization of the structure properties and thermally induced transformations of this porcelain. It has been found that the material possesses superior strength and other properties relative to conventional porcelains. The improved properties appear to result from the presence of a very fine and relatively dense distribution of leucite crystals. Scanning electron microscopy indicates, however, that the …

Bone Ingrowth Into Porous Coated Canine Total Hip Replacements. Quantification By Backscattered Scanning Electron Microscopy And Image Analysis, Murali Jasty, Charles R. Bragdon, Steven Schutzer, Harry Rubash, Teresa Haire, William H. Harris

Scanning Microscopy

Bone ingrowth into titanium fiber mesh porous-surfaced canine total hip replacement prostheses was evaluated and quantified using a computer assisted image analysis system attached to a scanning electron microscope equipped with a back scattered electron detector. Excellent contrast between the bone, the porous metal and the soft tissues resulted in the backscatter mode, allowing easy differentiation of these components in real time by the image analysis based on gray scales. By three weeks the mean (± standard deviation) amount of bone ingrowth expressed as a percentage of porous layer measured 7.2% (± 1.5%) for the acetabular components, and 3.9% (± …

A Stereoscopic Scanning Electron Microscope Study Of Pulmonary Hypoplasia In Chondrodystrophic Mice, W. Bradford Hepworth, Robert E. Seegmiller

Scanning Microscopy

Pulmonary hypoplasia is a life threatening condition in newborns resulting from a generalized underdevelopment of the lungs. The lung disorder is usually secondary to conditions outside the lung such as thoracic volume reduction. The precise mechanism by which thoracic volume reduction prevents normal lung development and growth is unknown. As a model for human pulmonary hypoplasia associated with lethal skeletal dysplasia, a stereoscopic SEM study of chondrodystrophic (cho) fetal mouse lungs fixed by intratracheal instillation with 3% glutaraldehyde was conducted. In comparison with lungs of phenotypically normal littermates, the mutant's lungs appeared unaffected with respect to structure of major …

Changes In The Esophageal Epithelium In Rabbits Treated By Cis-Dichlorodiammineplatinum As Studied By Electron Microscopy, M. Albertsson, C. -H. Hakansson, M. Palmegren

Scanning Microscopy

The esophageal mucosa of the rabbit was investigated after a single dose of 5 mg Cis-Dichlorodiammineplatinum (Cis-DDP). Specimens were taken for scanning electron microscopy, transmission electron microscopy, and light microscopy. Examination was performed daily for 20 consecutive days. A cytotoxic effect was observed already the first day after injection with an intracellular oedema. Thereafter the height of the esophageal epithelium and the basal cell layer steadily decreased to a minimum day 11. This parallels the damaged microridges and an increased cell loss as revealed by scanning electron microscopy. At the end of the observation period the esophageal mucosa had completely …

The Effect Of 10 And 20 Gy Single Dose Irradiation On The Esophageal Mucosa Of The Rabbit. An Electron Microscopic Study, C. H. Hakansson, M. Albertsson, M. Palmegren

Scanning Microscopy

The mucosa of rabbit esophagus was irradiated with single doses of 10 and 20 Gy respectively. Specimens were taken for scanning electron microscopy (SEM), and light microscopy investigations. Examinations were made 1-14 days after 10 Gy and 1-17 days after 20 Gy. Irradiation resulted in edema during the first days. The thickness of the epithelium was at its lowest value around day 5 after the administration of 10 Gy, and on days eight to ten after the administration of 20 Gy. Damage of the epithelium surface, as scored on SEM micrographs, was most pronounced on days eight to eleven after …

Scanning Electron Microscopy Of Chromosomes And Chromosome Fragments In Transgenic Rainbow Trout, Jane E. Disney, Christine M. Davitt, Gary H. Thorgaard

Scanning Microscopy

Chromosomes and chromosome fragments from embryonic offspring of a transgenic rainbow trout were examined using scanning electron microscopy (SEM). SEM is an extremely useful technique for studying the structure of chromosome fragments since little morphological detail is revealed by conventional staining methodologies and light microscopy. The chromosome preparations were processed for SEM by combining an osmium-thiocarbohydrazide-osmium (OTO) technique with 2-4 nm of gold deposition. This technique revealed the organization of individual chromatin fibers in chromosome fragments and intact chromosomes. Both a linear chromosome fragment with a width similar to that of an intact chromatid (approximately 0.60 micrometers) and a spherical …

Scanning Electron Microscopy Of The Small Intestine Mucosa In Children With Celiac Disease After Long-Term Dietary Treatment, M. Morroni, A. Sbarbati, G. D'Angelo, C. Catassi, P. L. Giorgi, S. Cinti

Scanning Microscopy

Jejunal mucosal specimens from twenty children with celiac disease were studied by light microscopy (LM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) after one year of dietary treatment. An ultrastructural morphometric study was performed in five patients who had an intestinal permeability (IP) test. Seventeen patients were tested for serum antigliadin antibodies (AGA). In ten children, in whom LM showed partial villous atrophy, SEM and TEM examination confirmed the lesion. In the second group (10 children) with normal morphology at routine LM, SEM showed lesions of variable degree in 70% of cases. The morphological ultrastructural investigation showed good …

Backscattered Electron Imaging Using Single Crystal Scintillator Detectors, R. Autrata

Scanning Microscopy

The image obtained by the detection of backscattered electrons (BSE) becomes an indispensable complement to the correct interpretation and more precise reconstruction of the surface of the specimen and its material composition. The BSE are carriers of information which is dependent on their angular and energy distribution. The choice of a certain type of BSE and their efficient detection make it possible to record the desired information with a different grade of quality. The knowledge of the angular and energy distribution of BSE is necessary for the adjustment of the correct position of the BSE detector with regard to the …

Osteoclast Features Of Cells That Resorb Demineralized And Mineral-Containing Bone Implants In Rats, Cedo M. Bagi, Scott C. Miller

Scanning Microscopy

The comparative temporal tissue response to demineralized bone matrix powder (DBP) and devitalized mineral containing bone powder (MCP) implanted subcutaneously in rats was studied. The tissue response to implanted DBP followed the well described endochondral osteogenic pathway and included the appearance of osteoblasts and osteoclasts. On the other hand, implanted MCP resulted in the appearance of a large population of giant cells that resorbed the implants. At later times (3-4 weeks), most of the cells in the MCP implants appeared as typical foreign body giant cells with extensive membrane foldings, usually away from bone surface. Some cells did, however, have …

Morphology And Chemical Composition Of Dental Calculi Mainly Composed Of Whitlockite, Toshiro Sakae, Hirotsugu Yamamoto, Hiroyuki Mishima, Takashi Matsumoto, Yukishige Kozawa

Scanning Microscopy

The morphology and chemical composition of two subgingival calculus samples, which were composed of magnesium-whitlockite with a Mg/Ca molar ratio of approximately 0.1 as shown by X-ray powder diffraction, were analyzed semiquantitatively using energy-dispersive spectroscopy (EDS) combined with scanning electron microscopy (SEM). The Ca/P molar ratio values for 33 EDS-analyzed materials ranged from 1.24 to 2.03 with an average of 1.49, and the (Mg+Ca)/P molar ratio values ranged from 1.43 to 2.28 with an average of 1.63. The average Mg/Ca molar ratio was 0.10, a value very close to that obtained by X-ray diffraction analysis.

The EDS-analyzed materials were grouped …

Scanning Electron Microscopy Of Lung Following Alpha Irradiation, C. L. Sanders, K. E. Lauhala, K. E. Mcdonald

Scanning Microscopy

Pulmonary aggregation of inhaled ²³⁹PuO₂ particles leads to a cellular evolution of focal inflammation, fibrosis, epithelial dysplasia and lung tumor formation. Female Wistar rats were exposed to an aerosol of high-fired ²³⁹PuO₂ (initial lung burden, 3.9 kBq) and the lungs examined at intervals from 1 day to 700 days after exposure by light and scanning electron microscopy and autoradiography. Peribronchiolar Pu particle aggregation increased with time, resulting in well-defined focal inflammatory lesions after 120 days and fibrotic lesions after 180 days. A generalized hypertrophy and hyperplasia of nonciliated bronchiolar cells was seen at 15 days and …

Biuret Staining And X-Ray Microanalysis For Locating Grafted Poly(Methyl Acrylate) On Wool Fibers, R. R. Bresee, P. A. Annis

Scanning Microscopy

Biuret reagent was used to stain wool fibers with copper so the location of a small amount of poly(methyl acrylate) grafted onto the fibers could be determined by energy dispersive x-ray microanalysis of copper. The grafted polymer was determined to be located in regions of the fibers where cuticle had been previously damaged. The amount of grafted polymer present was too small for secondary electron imaging to be useful for locating the polymer grafts.

A Contribution To The Scanning Electron Microscope Based Microcharacterization Of Semi-Insulating Gallium Arsenide Substrates, D. Köhler, G. Koschek, E. Kubalek

Scanning Microscopy

The macroscopic behaviour of semiconducting materials is determined by the distribution of microscopic defects like dislocations, impurities and intrinsic defects. Therefore, microanalytical methods are necessary to control the influence of technological process parameters on the materials properties. In the case of GaAs substrates, measurements of the cathodoluminescence (CL) and the electron beam induced voltage (EBIV) as well as the new charging technique seem to be promising methods to perform this task. CL-micrographs of as-grown GaAs substrates show bright cellular structures, which correspond to dislocation networks. Comparative investigations by use of the new charging contrast technique indicate an increased conductivity in …

Recent Uses Of Electron Microscopy In The Study Of Physico-Chemical Processes Affecting The Reactivity Of Synthetic And Biological Apatites, J. D. B. Featherstone, D. G. A. Nelson

Scanning Microscopy

Studies which used scanning electron microscopy (SEM) to investigate subsurface demineralization of dental enamel have recently been well reviewed. The purpose of the present paper was to review several studies, carried out in our laboratories, which have used electron microscopy to examine physicochemical properties of synthetic and biological apatites, to relate these results to previous studies, and to present new data.

Aspects of the ultrastructure of hydroxyapatite and carbonated-apatites have been observed by high resolution transmission electron microscopy, and related to shape and growth of these crystals.

Surface morphologies of discs prepared from precipitated carbonated-apatites and from ceramic carbonated-apatites were …

Solution-Mediated Transformation Of Octacalcium Phosphate (Ocp) To Apatite, R. Z. Legeros, G. Daculsi, I. Orly, T. Abergas, W. Torres

Scanning Microscopy

OCP crystals were hydrolyzed in solutions containing Ca²⁺, Mg²⁺, HPO₄^2-, CO₃^2-, F^-, citrate or P₂O₇ ions. Products of hydrolysis were analyzed using scanning (SEM) and transmission (TEM) electron microscopy, infrared spectroscopy and x-ray diffraction.

Results demonstrated that the OCP to Apatite (AP) transformation is influenced by: (1) types of ions in solution: inhibited by Mg²⁺, citrate or P₂O₇^4-; facilitated by F^-, CO₃^2-, HPO₄^2- or Ca²⁺ ions; (2) ionic concentrations; (3) …

The Vascularization Of The Skin Of The Atlantic Hagfish, Myxine Glutinosa L. As Revealed By Scanning Electron Microscopy Of Vascular Corrosion Casts, A. Lametschwandtner, T. Weiger, U. Lametschwandtner, V. Georgieva-Hanson, R. A. Patzner, H. Adam

Scanning Microscopy

The vascularization of three different (A, B, C) skin regions (from the level of the heart to the cloaca including dorsal, lateral and ventral skin areas) of the Atlantic hagfish, Myxine glutinosa L. was studied by scanning electron microscopy of vascular corrosion casts. Vessel variables were measured either from semithin sections (diameters) or from vascular corrosion casts (diameters, lengths) and total blood capacities as well as vessel surfaces per unit skin area (mm²) were calculated. There are no significant differences in the number of subepidermal capillary meshes (ranging from 164 to 185 meshes per micrograph) in areas A, …

Ranking Corrosion Efficiency: A Latin Square Study On Rat Lung Microvascular Corrosion Casts, Dean E. Schraufnagel

Scanning Microscopy

Scanning electron microscopy of corrosion casts is an important tool for the study of microvascular structure but few systematic studies on methods of specimen preparation have been reported. This study sought to determine the relative importance of factors involved in corrosion. It compared potassium hydroxide, sodium hydroxide and water as major corrosive agents. It tested the size of the tissue sample, and the use of prealkali autolysis, detergent, and proteolytic enzymes in a Latin square designed study. The main findings were that sodium and potassium hydroxide were better than water (P < 0.0001) and the longer the corrosion time the better corroded the samples were (P < 0.0001 ). Although not a controlled factor, higher room temperature was also associated with better corrosion. The use of proteolytic enzymes, detergent, and warm tap water alone before the alkali treatment did not significantly improve the corrosion in this study, although this does not preclude an effect with another experimental design.

Scanning Electron Microscopy In The Study Of Campylobacter Pylori Associated Gastritis, F. Bonvicini, P. Versura, S. Pretolani, G. Gasbarrini, R. Laschi

Scanning Microscopy

The close association between Campylobacter pylori (CP), gastritis and peptic ulcer is now well established. Moreover increasing evidence has been collected of a major etiological role of CP in type B chronic gastritis. For this reason, searching for CP is essential in all patients with upper gastrointestinal symptoms.

Scanning electron microscopy (SEM) is a most reliable technique for studying the distribution of microorganisms and their relationship to the gastric mucosal surface.

The aim of this paper is to compare SEM to other routine methods of detection for CP, such as Giemsa staining on histological sections and Urease Microtiter Test (MT) …

Architecture Of The Medial Smooth Muscle Of The Arterial Vessels In The Normal Human Brain: A Scanning Electron-Microscopic Study, Toshitaka Shiraishi, Saburo Sakaki, Yasuo Uehara

Scanning Microscopy

The architecture of the medial smooth muscle of arterial vessels in normal human brains was investigated using scanning electron microscopy. We could divide the arterial vessels into four subdivisions according to the number of the circular muscle cells. The arteries ( > 100 μm in diameter) had 4-20 layers of circular smooth muscle cells; individual circular muscle cells were spindle-shaped and occasionally had branches at their ends. Multidirectional muscle cells were observed in the medio-adventitial border only at the branching sites in large arteries (>300 μm), but at both branching and non-branching sites in the small arteries (100-300 μm). The …

Analyses Of Dental Pulp In Restored Teeth, D. L. Lentz, J. T. Buchanan, D. R. Basinger

Scanning Microscopy

Restored teeth were extracted from test animals at four time intervals (1 hour, 1 day, 1 week, and 3 months) following amalgam insertion. Extracted teeth were frozen in liquid nitrogen, cryo-fractured so as to expose the pulps and then freeze-dried. Pulps were analyzed for mercury content by energy dispersive spectrometry (EDS) and atomic absorption spectrophotometry (AAS). Mercury levels appeared below the detection limits of EDS but could be detected by AAS which showed the highest readings seven days after amalgam insertion.

Scanning Electron Microscope And X-Ray Diffraction Investigations Of Mudrock Fabrics, Textures And Mineralogy, J. M. Huggett

Scanning Microscopy

Mudstones from a broad range of depositional environments have been investigated to determine whether fabric, texture or mineralogy may (1) be used to identify the environment of deposition and (2) be correlated with poroperm. The diversity of fabrics and textures reflects features of the detrital mudstone composition, compaction and diagenesis, rather than environment of deposition. Preferred orientation has been disturbed by bioturbation and growth of post-compactional authigenic minerals; these factors have reduced to nil any correlation which may have existed between fabric, measured as the illite orientation ratio (O/R) and environment of deposition.

It is mineralogy rather than fabric or …

Preparation Of Dipteran Larvae For Scanning Electron Microscopy With Special Reference To Myiasigen Dipteran Species, I. Ruiz-Martinez, M. D. Soler-Cruz, R. Benitez-Rodriguez, M. Diaz Lopez, J. M. Perez-Jimenez

Scanning Microscopy

Although controversy exists concerning the role of chemical fixatives in scanning electron microscopy (SEM) studies of Dipteran larvae, we have observed that filtered 10% formaldehyde solution gives excellent results as a preservative. After immersing in vivo in formaldehyde, the larvae material is preserved for prolonged periods (up to 8 months), before examination with SEM. As a fixative, formaldehyde preserves the structure of the larval cuticle and produces no visible artifacts. Moreover, postfixation is not necessary.

Due to pecularities of the way of life of Wohlfahrtia magnifica (principally the accumulations of necrotic tissue, purulent particles, and other types of substances that …

The Vascular System Of Xenotransplanted Tumors -Scanning Electron And Light Microscopic Studies-, M. A. Konerding, F. Steinberg, V. Budach

Scanning Microscopy

A widely used model for investigating basic tumor characteristics and different treatment modalities preclinically is the immune-deficient, athymic nude mouse. This model offers many morphological parallelisms to the clinical situation.

The aim of this study is to demonstrate the vascularization pattern of xenotransplanted human melanomas and sarcomas using different methods. Xenotransplanted tumors of 62 congenital thymusaplastic nude mice were examined ultrastructurally and topographically after corrosion cast and tissue preparation. Quantitative measurements of tumors injected with India ink were carried out to obtain comparable information on the vascular densities in the tumors.

Quantitative measurements showed that there is no zonal, topographic …

Vascular "Sphincter" And Microangioarchitecture In The Central Nervous System: Constriction Of Intraparenchymal Blood Vessels Following A Treatment Of Vasoconstrictive Neurotransmitter, K. Nakai, Y. Naka, H. Yokote, T. Ikatura, H. Imai, N. Komai, T. Maeda

Scanning Microscopy

The site of action of neuropeptide Y (NPY), a potent vasoconstrictive neurotransmitter, on the intraparenchymal blood vessels in the rat parietal cortex was demonstrated using a corrosion cast technique with scanning electron microscopy. Our observations were confined to the cortical area where the regional cerebral blood flow (rCBF) had been reduced significantly by in situ application of NPY. A striking finding in that area was the diffuse narrowing of the perforating arteries in the upper cortical layers. Ring-like compressions on the corrosion casts, presumably formed by active vascular sphincters along the arteries, capillaries and venules within the brain parenchyma, seemed …