Biology Commons^™

Effects Of Fractionated Irradiation On The Esophageal Mucosa: A Scanning And Transmission Electron Microscopic Study, M. Albertsson, C-H Hakansson, C. Mercke, H. Morner

Scanning Microscopy

The mucosa of rabbit esophagus was irradiated with daily fractions of 2 Gy to an accumulated dose of 20 Gy. Specimens were taken for scanning electron microscopy, transmission electron microscopy and light microscopy investigations. Examination was made 1-10 days after each fractionation schedule. Light microscopy showed dose-dependent edema of the irradiated mucosa which also could be seen and scored from SEM pictures. SEM investigations showed that this was accompanied by loosening of microridges and a slightly increased cell loss. By SEM, a varying amount of bacteria could be seen which did not make intimate contact with the surface cells.

During …

Effects Of Cis-Dichlorodiammineplatinum Alone And In Combination With Ionizing Radiation On The Esophageal Mucosa: A Scanning And Transmission Electron Microscopic Study, M. Albertsson, C-H Hakansson, C. Mercke

Scanning Microscopy

Cis-dichlorodiammineplatinum (cis-DDP) has for more than 20 years been part of the therapeutic arsenal of oncology. Most of the knowledge about its biological action is based on clinical investigations and therefore an examination of the influence of cis-DDP at the cellular and sub-cellular level is necessary. Five mg of cis-DDP was given intraperitoneally (i.p.) to ten rabbits. Ultrastructural examinations were performed on the upper and lower parts of the esophagus each day after the injection on the following ten days. Another 50 rabbits were given 5 mg cis-DDP and were irradiated in an area just beneath the hypopharynx. They were …

Characteristics Of An Electric/Magnetic Quadrupole Detector For Low Voltage Scanning Electron Microscopy, M. Brunner, R. Schmid

Scanning Microscopy

The electric/magnetic quadrupole detector allow's efficient detection of secondary electrons in low voltage scanning electron microscopy without introducing disturbing aberrations. The original detector of this type was built in 1986; it has now been equipped with scintillator-photomultiplier assemblies on both positive electrodes. Their signals, A and B, can be combined to A+B or A-B, thus enhancing or suppressing different types of contrast. The aberration disc produced by the present design of detector was estimated to have a diameter of 10 nm. Experimentally, no deterioration of image resolution was observed. The collection efficiency was predicted to be 26% and can be …

Scanning Electron Microscopy Of Vascular Smooth Muscle Cells From Rat Muscular Arteries, William J. Krizmanich, Robert M. K. W. Lee

Scanning Microscopy

The use of scanning electron microscopy (SEM) for the examination of medial smooth muscle cells (SMC) is limited by the presence of connective tissue mass in the adventitia obscuring the detailed structure of the SMC. This study deals with the description of a method which selectively removes the connective tissue, allowing three dimensional observation of SMC using SEM. A number of methods were tried. One method involving post fixation with 2% Os0₄ used in conjunction with HCl proved most successful in removing the extracellular matrix of large mesenteric arteries from spontaneously hypertensive rats (SHR) and age-matched Wistar-Kyoto normotensive rats …

Multiplane Sectioning And Scanning Electron Microscopy As A Method For Studying The Three-Dimensional Structure Of Mature Dental Enamel, S. Risnes

Scanning Microscopy

A method is described where teeth are sectioned/ground along at least two planes, etched, and viewed at various angles in the SEM in order to study the three-dimensional structure of enamel. This multiplane sectioning-scanning electron microscopy (MPS-SEM) method has been applied to the study of rat and human enamel. The method demonstrates in a direct way the complex three-dimensional structure of rat incisor enamel; the path of prisms and the distribution of interprismatic substance. The different appearance of alternate prism rows as seen in the longitudinal plane is seen to be due to prisms in alternate rows being inclined to …

The Fine Structure Of The Human Placental Villus As Revealed By Scanning Electron Microscopy, G. J. Burton

Scanning Microscopy

Scanning electron microscopy of the placenta has a history of only twenty years. During that time, however, there have been dramatic advances in instrument technology coupled with the refinement of preparative techniques designed to reduce fixation artifacts to a minimum. As a result many of the early claims must be amended or suitably qualified, and this is one aim of the present review.

Much new data on the internal structure of the placental villus is also presented. By means of the partial digestion technique it is now possible to describe the three dimensional configuration of the various components of the …

Intrauterine Device (Iud) Associated Pathology: A Review Of Pathogenic Mechanisms, Waldemar A. Schmidt, Karmen L. Schmidt

Scanning Electron Microscopy

This paper summarizes our studies of IUD-related disease with those previously published by others. Our data are based upon 51 IUDs and 42 index cases of IUD-related disease demonstrating specific processes. Gross, dissecting microscope, scanning electron microscope and X-ray microanalysis examinations were made of selected IUDs and associated tissues. Tissue associated with the IUDs revealed inflammation in 59.4%, calcific material in 6.3% and no abnormality in 34.4%. JUD-associated tissue responses were accompanied by changes of the IUD; these changes involved deposition of substances upon the IUD surface and degradation of the JUD itself. Disintegration of the IUD, its string or …

Scanning And Transmission Electron Microscopic Study Of Recovered Porcine Aortic Valved Conduits, D. J. Allen, I. H. Fentie, J. T. Davis, Angela Lineen

Scanning Electron Microscopy

Four explanted porcine aortic valved conduits were examined using scanning and transmission electron microscopy. Sources of obstruction such as neointima or "peel" and calcification were observed. In one sample the neointima was found to possess an unusually large expanse of squamous cells partially lining the luminal surface. This lining much resembled a normal endothelium, which is not an expected feature of neointima. Cells, presumably of host origin, were noted upon the leaflet surfaces. They did not seem as well organized as those found on the neointima. Calcification did not seem greatly advanced but was clearly apparent. Certain treatments proposed by …

Intracellular Structure Of The Outer Hair Cell Of The Organ Of Corti, Y. Harada, T. Sakai, N. Tagashira, M. Suzuki

Scanning Electron Microscopy

The intracellular structure of the outer hair cells of the normal guinea pig organ of Corti was investigated three dimensionally by scanning electron microscope. Freeze fracturing technique followed by maceration with a 0.1% OsO₄ solution (osmic maceration method) was used. Among the cell organelles, the endoplasmic reticulum (ER) showed the most interesting features, such as subsurface cisternae and lamellar bodies. The subsurface cisterna which formed a stratiform network covered the inner surface of the cell membrane and the stratiform structure disappeared at the infranuclear region. Variously shaped mitochondria (spherical, cylindrical and branched) were found on the innermost layer of …

Scanning Electron Microscopic Observation Of The Crista Ampullaris, Y. Harada, M. Takumida, N. Tagashira

Scanning Electron Microscopy

The crista ampullaris of the guinea pig and the bull frog were investigated by scanning electron microscopy. The crista ampullaris were freeze fractured or sheared followed by maceration with 0.1% OsO₄ solution. Following this, three-dimensional intracellular structures were observed. The mitochondria of the sensory cells varied in shape from globular to long and slender. Golgi apparatus and endoplasmic reticulum of the sensory cells were also demonstrated clearly. Nerve elements, nerve endings and synaptic structures were also observed stereoscopically.

Ultrasonic Microdissection Of Immature Intermediate Human Placental Villi As Studied By Scanning Electron Microscopy, Gregory J. Highison, F. Donald Tibbitts

Scanning Electron Microscopy

The human placenta during the first 20 weeks of gestation undergoes rapid and extensive morphological changes. Near the end of this period, the most predominant type of villus present is the immature intermediate placental villus. In order to visualize this complex structure with scanning electron microscopy (SEM), we have developed a microdissection technique to expose tissue components of the placental villus while retaining its normal histological architecture. Placental villi were initially fixed in Karnovsky's fixative, buffered formalin, or 2% osmium tetroxide solution prior to exposure to connective tissue enzymes or detergents alone or in combination. Samples were dehydrated through 100% …

Urolithiasis In A Patient Ingesting Pure Silica: A Scanning Electron Microscopy Study, D. B. Leusmann, J. Pohl, G. Kleinhans

Scanning Electron Microscopy

A patient who repeatedly produced urinary calculi, had consumed about 3g of cristobalite (SiO₂) per day for many years. Investigations using scanning electron microscopy revealed minute particles containing silicon in the core of the stone as well as in urine sediment. A mechanism similar to that proposed for the effect of silicon-containing drugs against gastric ulcer, may play a role in this formation of silicon-containing urinary stones.

The Identification And Characterization Of Metal Wrappings In Historic Textiles Using Microscopy And Energy Dispersive X-Ray Spectrometry: Problems Associated With Identification And Characterization, N. Indictor, R. J. Koestler

Scanning Electron Microscopy

Scanning electron microscopy-energy dispersive x-ray spectrometry (SEM-EDS) has been employed for the description of metal wrapped yarns. Although considerable detail is obtainable as microphotographs, and elemental analysis is obtained with ease, caution should be exercised in interpreting results. Several unravelled samples should be examined; light microscopy should be employed prior to SEM-EDS analysis. Examination of eight specimens (six from the textile collection of the Metropolitan Museum of Art, New York; two from private collections) is described. The samples were Chinese (5), German (1), Spanish (1), Turkish (1). Difficulties encountered in describing this set of samples are enumerated.

Lack Of Regional Surface Differences In Mouse Bladder Urothelium: A Scanning Electron Microscopic Study, Kari Feren, Jon B. Reitan

Scanning Electron Microscopy

The surface structures of mouse urinary bladder epithelium, the urothelium, were examined in SEM. The entire surface area of both a moderately and a well stretched bladder were studied. No regional differences were found in either case. The moderately stretched bladder showed deep folds, while the well stretched bladder had only small folds giving the bladder an accordion-like appearance. In both bladders the typical surface structures were microridges arranged in a honeycomb-like pattern. The present study indicates that focal or regional differences found in bladders treated with chemicals or exposed to radiation are a result of the treatment itself, and …

Scanning Electron Microscopy Of The Irradiated Mouse Bladder Urothelium, Jon B. Reitan, Kari Feren

Scanning Electron Microscopy

The luminal surface of mouse bladder urothelium was studied by scanning microscopy 1 year after irradiation with 0, 10 and 20 Gy respectively. The controls that were anaesthetized only displayed surface characteristics indistinguishable from normal urothelium.

Irradiation with 10 Gy did not result in marked overall changes in the scanning electron microscopic features of the luminal aspect, but in some areas alterations comparable to the alterations after 20 Gy were observed. After irradiation with 20 Gy focal hyperplastic areas, superficial early ulceration and dedifferentiation of cover cells were seen. The dedifferentiation to featureless cells is probably not associated with increased …

Functional Aspects Of Renal Glomeruli Based On Scanning Electron Microscopy Of Corrosion Casts, With Special Emphasis On Reptiles And Birds, H. Ditrich, H. Splechtna

Scanning Electron Microscopy

The glomerular complexity of several species of birds and reptiles is investigated in this study by scanning electron microscopy of vascular corrosion casts. Comparing these results with those of a freshwater teleost and a mammalian species, a trend towards small, simple glomeruli of the avian type, beginning with large, well vascularized glomeruli resembling the type found in fish, can be observed in reptiles.

A close correlation between glomerular size and habitat can be established comparing related species having a similar physiological mode of renal function.

Entirely different from this sauropsidian evolutionary line of development is the highly complex, large differentiation …

Computer Simulation And Experimental Performance Data For An Electron Spectrometer For Electron Beam Testing Of Integrated Circuits, D. Deutges, S. Görlich, E. Kubalek

Scanning Electron Microscopy

Electron beam testing using voltage contrast in the scanning electron microscope has been established as a useful tool for nondestructive and nonloading functional testing and failure analysis of integrated circuits (IC). The accuracy of quantitative voltage measurements within the IC with the electron beam probe is determined by the performance of the secondary electron (SE) spectrometer used.

For simulating the performance of SE-spectrometers a program-package has been developed by aid of which the voltage-and field-distributions within the spectrometers can be evaluated using a finite element method. Thus it is possible to trace electron trajectories throughout the spectrometer. By considering a …

Scanning Electron Microscopic Studies On Microvascular Architecture Of Human Coronary Vessels By Corrosion Casts: Normal And Focal Necrosis, T. Ono, Y. Shimohara, K. Okada, S. Irino

Scanning Electron Microscopy

Microvascular architecture of the normal human heart and myocardial focal necrosis were studied by scanning electron microscopy of corrosion casts. Casts macroscopically identical in form to the left ventricular posterior wall were prepared.

The following results were obtained in the normal human heart. (I) Most of the arterioles communicated with capillary plexuses smoothly and straight forwardly in the left ventricular posterior free wall. (2) Arterioles which branched from the arteries ran in various directions and continued into capillaries either at right angles or obliquely in the trabeculae carneae. (3) capillaries running parallel with the cardiac muscle fibers ran in different …

Surface Studies Of Duodenal Lesions Induced By Thoracic Irradiation, K. E. Carr, S. Ellis, A. Michalowski

Scanning Electron Microscopy

Acute duodenal ulcers are produced in mice as a remote ("abscopal") effect of irradiation to the lower mediastinum. Such lesions have been examined with scanning electron microscopy at 5, 8 and 28 days after irradiation with 18 Gy of X-rays. All the ulcers occur within the first 1 cm long segment of the duodenum which is endowed with Brunner's glands. The single lesions vary in size, shape and position. The damaged area often includes much of the duodenal circumference and is distinguished by conical or rudimentary villi, or even by the complete absence of villi. In contrast, around the periphery …

Scanning Electron Microscopy Of Human Metaphase Chromosomes, T. D. Allen, E. M. Jack, C. J. Harrison, D. Claugher

Scanning Electron Microscopy

Preparative methods for scanning electron microscopy of chromosomes are dependent on the original source of material. Chromosomes extracted from unfixed metaphase cells via isolation buffers tend to show topography and surface morphology which may have been induced by the choice of isolation buffer itself. Furthermore, this type of preparation often precludes any chromosome identification, as many metaphases have been pooled, and also the chromosomes from these preparations are not suitable for the banding techniques regularly used in clinical cytogenetics. Our own approach has been to use the standard cytogenetic approach, starting with methanol-acetic acid fixed, air dried metaphase spreads, allowing …

Analytical Ultra High Vacuum Scanning Electron Microscopy With Field Emission Gun For Surface Study, P. Morin, P. Abraham, C. Bablet, M. Tholomier

Scanning Electron Microscopy

Surface studies can be carried out with a scanning electron microscope (SEM) having an ultra high vacuum specimen chamber. The main application of this SEM was the micro Auger analysis, but it is also interesting to combine the usual surface study technique with SEM observations. Indeed, these latter give valuable in formation about the topographic, chemical and crystallographic aspects of the surface when the secondary, backscattered and transmission SEM modes are used. The SEM performances are increased by the use of a field emission gun, the high brightness beam of this gun gives new observation possibilities such as the imaging …

The Cathodoluminescence Mode Of The Scanning Electron Microscope: A Powerful Microcharacterization Technique, D. B. Holt, F. M. Saba

Scanning Electron Microscopy

By detecting cathodoluminescence (CL) in a scanning electron microscope (SEM), pan and monochromatic micrographs and CL spectral analyses analogous to x-ray mode point analyses can be obtained. Complete microcharacterization requires alternate examination of both micrographs and spectra. New techniques for near infra-red CL and low-temperatures to produce sharp spectra are of increasing importance. CL emission is due to electron transitions between quantum mechanical states so the radiative defects present can be unambiguously identified at liquid helium temperatures. Strongly luminescent impurities can be detected to below one part in 10⁸. This is 10⁴ times as sensitive as the …

Clinical Applications Of Scanning Electron Microscopy In Gastrointestinal Diseases, F. Bonvicini, G. Zoli, M. C. Maltarello, D. Bianchi, G. Pasquinelli, P. Versura, G. Gasbarrini, R. Laschi

Scanning Electron Microscopy

We considered the role of scanning electron microscopy (SEM) in clinical investigation of different gastrointestinal diseases. The following clinical applications of SEM may be suggested on the basis of our original data and those reported in literature:

in peptic ulcer: assessment of the completeness of healing, by observing the mucosal surface architecture of the scars; identification of mucosal changes, namely enterocytic surface membrane alterations, predictive of recurrence;

in coeliac disease: early assessment of the response to gluten-free diet and follow-up of the patients by staging the process of mucosal repair in cerebriform, intermediate and villous patterns;

in ulcerative …

Scanning Electron Microscopy Of The Human Myocardium, S. Siew

Scanning Electron Microscopy

Owing to the impossibility of fixation, in the human being, by means of perfusion in vivo and the rare availability of fresh comparatively intact hearts resected at transplantation, the possibility was explored of using post-mortem material in instances where the autopsies were performed within 2 hours of demise of the patients. Four cases were examined: 2 normal adult hearts and 2 hearts of hypertensive patients in the stage of decompensation. The hearts were fixed by means of perfusion with 2.5% glutaraldehyde in phosphate buffer, pH 7.4. Contiguous blocks were taken for light microscopy (LM) and scanning electron microscopy (SEM) from …

Use Of Polymer Casts Or Metal Particle Infusion Of Ducts To Study Antigen Uptake In The Guinea Pig Mammary Gland, D. I. Schenkman, D. T. Berman, R. M. Albrecht

Scanning Electron Microscopy

Microcorrosion casts were made of the duct system of guinea pig mammary glands by intramammary infusion of Mercox® polyester resin following involution of the glands after the first lactation. The acinar configuration of the involuted gland was apparent on examination of the casts by scanning electron microscopy (SEM). Surface features, which were readily identified as those of imprints of duct al epithelium, were visible at higher magnifications. The morphology of these casts corresponded to the patterns observed by SEM of ethanol cryofractured specimens of mammary tissue.

Cryofractured specimens of guinea pig mammary glands were also examined by SEM following intramammary …

Sputter Crater Contour Mapping With Multilayered Films, L. L. Levenson, T. P. Massopust, J. Dick, M. C. Jaehnig, D. Griffith

Scanning Electron Microscopy

Multilayered films composed of alternating 200 Å Al and 267 Å Al203 layers are made by physical vapor deposition. Twenty-two pairs of these films are deposited on a polished Si wafer. Ion beam sputtering is used to form craters in the multilayered film. When a crater is viewed or photographed in situ by scanning electron microscopy, the Al₂O₃ layers appear bright and the Al layers appear dark. In the scanning electron microscope (SEM) the Al₂O₃ layers have a high secondary electron yield compared to Al. In secondary ion mass spectrometry (SIMS), using Cs^{+ …}

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 …

The Ballistic Phonon Signal In Low Temperature Scanning Electron Microscopy, R. P. Huebener, W. Metzger

Scanning Electron Microscopy

By scanning the surface of a specimen cooled to liquid-helium temperature with the electron beam, ballistic phonons are generated which can be used for acoustic imaging. The anisotropy of the ballistic phonon propagation caused by the phonon focusing effect has been observed in recent experiments. The simultaneous operation of two or more small-area phonon detectors during the scanning process appears promising for three-dimensional acoustic imaging of structural inhomogeneities even far from the specimen surface. The principles of this scheme for acoustic imaging are discussed and the spatial resolution limits are estimated.

The Use Of The Scanning Electron Microscope In Studying The Heat Treatment Of Prehistoric Lithic Artifacts From The North Florida Weeden Island Period Mckeithen Site, G. Michael Johnson

Scanning Electron Microscopy

In this paper, I discuss a study in which I attempted to determine whether or not the inhabitants of the McKeithen site, a Weeden Island Period mound and village complex in what is today northern Florida, employed heat treatment as part of their lithic reduction technology, and if so, at what point in the reduction sequence it was conducted. I used a scanning electron microscope (SEM) to photograph raw and heat treated control samples of northern Florida chert, then debitage and tools of chert and silicified coral from the McKeithen site which represented the range of colors and luster present …

Microprobe Analysis In Human Pathology, D. Baker, K. G. Kupke, P. Ingram, V. L. Roggli, J. D. Shelburne

Scanning Electron Microscopy

This tutorial paper reviews the literature on the application of microprobe analysis to practical problems in diagnostic human pathology. The goal is to allow the reader ready access to the literature on specific clinical problems. Specimen preparation and commonly encountered artifacts are also considered. It is concluded that energy dispersive x-ray microanalysis and backscattered electron imaging are at present the most generally useful microprobe techniques for clinical work, and are no longer solely research tools. The findings often have diagnostic, therapeutic, and/or legal implications.