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Letter To The Editor By M.C. Deruiter And A.C. Gittenberger-De Groot Relating To: "Technical Improvements In Corrosion Casting Of Small Specimens: A Study On Mesonephric Tubules And Vessels Of Chicken Embryos." [By A. Carretero, H. Ditrich, M. Navarro, H. Splechtna, J. Ruberte, Scanning Microscopy Vol. 7(4), P. 1333-1338 (1993)]., M. C. Deruiter, A. C. Gittenberger-De Groot

Scanning Microscopy

Dear Editor,

The topic of scanning electron microscopy (SEM) investigation of casting of vessels in the embryo still holds our interest. We are particularly focused on the possibilities of early injection as a method to support angiogenesis and vasculogenesis research in the embryo. It is questionable whether our technique leads to unreliable results because of severe trauma to the embryo as suggested by the above mentioned authors. The lower success yield might very well be the result of the higher friability of the embryo in general in this young stage.

Diluted And Undiluted Mercox Severely Destroy Unfixed Endothelial Cells. A Light And Electron Microscopic Study Using Cultured Endothelial Cells And Tadpole Tail Fin Vessels, J. Gassner, A. Lametschwandtner, T. Weiger, H. C. Bauer

Scanning Microscopy

Mercox is a methylmethacrylate-based resin which is widely used for vascular corrosion casting with subsequent scanning electron microscopic analysis. In the present study the effect of undiluted and diluted Mercox (4+1; volume + volume; Mercox: monomeric methylmethacrylate (MMA); 0.02 g catalyst MA/ml Mercox) and methylmethacrylate with and without catalyst MA (0.625 g/10 ml MMA) on fixed and unfixed endothelial cells was studied. Light microscopy (LM) of cultured capillary endothelial cells (ECs), which were replicated with diluted or undiluted Mercox shows degranulation and membrane perturbation of ECs, while no morphological changes occur in glutaraldehyde-prefixed ECs. Scanning electron microscopy (SEM) of replicas …

Electronic Trap Microscopy - A New Mode For Scanning Electron Microscopy (Sem), H. -J. Fitting, Th. Hingst, R. Franz, E. Schreiber

Scanning Microscopy

Insulating layers on conducting substrate are investigated by means of secondary electron field emission SEFE in a digital SEM. The kinetics of charge storage and release with time and temperature are controlled and recorded by an external computer.The evaluation is performed pixel-wise with respect to electronic trap concentration n_t0, trap capture cross section σ_c and thermal activation energy E_t. Mapping of these trap parameters indicates hidden inhomogenities, defects and pre-treatments of the dielectric layers as well as the pattern of thermal bleaching and release of electrons. The latter ones appear as inhomogeneous processes starting with …

Microvascular Corrosion Casting Of The Rat Mandibular Joint: A Technical Approach, Etienne Piette, Alois Lametschwandtner

Scanning Microscopy

The rat mandibular joint is a ginglymoarthrodial joint deeply hidden under the zygomatic process of the squamosal bone. This joint was studied by scanning electron microscopy (SEM) of microvascular corrosion casts in 47 adult rats. Six additional rats were injected with India ink and thick sections of the joint area were examined by light microscopy. The small size of the joint (2.5 mm x 1.5 mm in occlusion), the existence of two slit-like joint compartments, the close proximity of bones and soft tissues in a mobile structure, and the intimate relationships of the joint with adjacent skeletal muscles made the …

Detection Of Topographic Contrast In The Scanning Electron Microscope At Low And Medium Resolution By Different Detectors And Detector Systems, J. Hejna

Scanning Microscopy

Origins of topographic contrast in the scanning electron microscope (SEM) are different at different resolution levels. At low resolution, tilt contrast of large features dominates; at medium resolution, diffusion contrast of features smaller than an interaction volume of primary electrons dominates.

The secondary electron (SE) signal, commonly used in the SEM, does not give a good tilt contrast; better contrast can be obtained with backscattered electron (BSE) signal of a converter and a sector-shaped ring detector. For obtaining topographic images from signals containing topographic and material contrast, signals of detector systems containing two or more detectors are mixed. Detector systems …

Stereometry Of Crystalline Phases Observed In Scanning Electron Microscopy, M. A. Martínez, J. M. Gómez De Salazar, A. J. Criado

Scanning Microscopy

A study of edges and angles of known samples has been performed by means of stereoscopic pairs with electron microscopy in two and three dimensional systems. The derived equations have been included in a computer program. Measurements on stereoscopic pairs with different tilt angles using several crystals of galena, calcite and other objects with known dimensions have been performed. The optimum tilt angles have been obtained by comparison with the actual values, and a logarithmic ratio between these angles and the stereoscopic pairs magnification has been found. The errors obtained using this system of calculation are lower than 6% in …

Scanning Electron Microscopy And Energy-Dispersive X-Ray Microanalysis Studies Of Several Human Calculi Containing Calcium Phosphate Crystals, Tetsuo Kodaka, Kazuhiro Debari, Tsuneyoshi Sano, Masayuki Yamada

Scanning Microscopy

Human calcium phosphate calculi: two sialoliths, a urolith, a rhinolith, and a tonsillolith were investigated by scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX). The sialoliths and urolith had appositional shells with thick cortices, respectively, around several nuclei composed of calcospherulites and a rubber-film fragment. The rhinolith had a thin cortex with appositional laminations around a glomerulus-like mass of calcified cotton-like strings. The tonsillolith had a rough cortex with appositional laminations. Its porous interior was composed of numerous calcified conglomerates with microorganisms and calcified masses with fine appositional laminations around the conglomerates. The major crystals were identified as biological …

Scanning Electron Microscopic Study Of The Three-Dimensional Structure Of The Collagen Networks Of Gastric Cancer, Masuki Iyoki, Keijiro Araki, Takuro Ogata

Scanning Microscopy

The three-dimensional structure of the collagen networks in human gastric carcinoma was examined by scanning electron microscopy (SEM) after treatment with the cell-maceration method using a low temperature NaOH solution. Based on stromal content, the poorly differentiated adenocarcinoma can be divided into the medullary carcinoma area and the scirrhous carcinoma area. In the medullary carcinoma, the collagen sheath around the small tumor cell acinus formed spherical chambers (20-30 μm in diameter) with fenestrations (about 5 μm in diameter) connecting the chambers. The collagen sheath was composed of fine collagen fibrils (about 50 nm in diameter). In the scirrhous area, there …

Collagen Fiber Arrangement In Temporo-Mandibular Joint (Tmj) Disks From Human Subjects With Functional Diseases. Scanning Electron Microscopy Investigations, C. Piacentini, C. Marchetti, G. Bernasconi, P. Menghini, U. Baciliero, C. Brusotti

Scanning Microscopy

Twelve articular disks from patients with temporo-mandibular joint (TMJ) arthropathy were studied and compared with two normal disks. Scanning electron microscopy (SEM) examination of the surfaces and of longitudinal and cross-sections of the disks allowed the observation of the arrangement of the collagen fiber component in different parts of the disk. The superficial part of the articular disks appears to be formed by rather compact fibers. The internal portion is usually formed by bundles of collagen fibers in sheets, alternating with isolated fibers arranged in a parallel or irregular way.

In some samples, blood vessels were observed. Our investigations suggested …

Influence Of A Corpus Luteum Tissue Extract On Rabbit Ovarian Mesothelial Cells, S. V. Nicosia, R. J. Narconis, B. O. Saunders

Scanning Microscopy

This study investigates rabbit ovarian mesothelial (OM) cells exposed in vitro to a crude corpus luteum extract (CLE; 60 μg/ml). The growth of OM cells was evaluated by measuring the change in cell number (mean % ± standard error of mean, SEM), the number of cell population doublings (CPD ± SEM), and the cell population doubling time in hours (CPDT ± SEM) after 7.5 days of culture in a serum-poor medium. Quantitative estimates of surface morphology changes were obtained by analyzing the total number (mean no. ± SEM), density (mean no./100 μ.m² ± SEM), and length-to-diameter ratio (mean L/D …

An Experimental Scanning Electron Microscopic Study Of Human Cerebellar Cortex Using The T-Butyl Alcohol Freeze-Drying Device, Teruyuki Hojo

Scanning Microscopy

Specimen preparation methods are very important in scanning electron microscopy (SEM) of nerve tissues. In the present study, a t-butyl alcohol freeze-drying device was used to prepare cerebellar cortex of the human and that of the rat at 15°C and 160 mm Hg. This method has been previously used with success in the preparation of other tissues, such as pancreas and trachea. Relatively large specimens (about 10 mm x 15 mm x 1 mm) of formalin-fixed human and glutaraldehyde-Millonig buffer perfused (1 hour) Wistar rat were rinsed in water, dehydrated in a series of ethanols, immersed in t-butyl …

Conventional And High Resolution Scanning Electron Microscopy And Cryofracture Techniques As Tools For Tracing Cerebellar Short Intracortical Circuits, Orlando J. Castejón, Robert P. Apkarian, Consuelo Valero

Scanning Microscopy

The present paper shows the potential contribution of conventional and high resolution scanning electron microscopy (SEM) to trace short intracortical circuits in cryofractured fish, primate and human cerebelli. Conventional SEM slicing technique allowed us to identify afferent mossy and climbing fibers and their synaptic relationship in the granular layer. SEM freeze-fracture method exposed the mossy glomerular synapses and the axo-dendritic connections of climbing fibers. At the Purkinje cell layer, the cryofracture process removed the satellite Bergmann glial cell layer, displaying a partial view of the supra-and infra-ganglionic plexuses of Purkinje cells and the ascending pathways of climbing fibers. High resolution …

Scanning Electron Microscopic Examination Of The Putative Olfactory Structures Possessed By The Phorid Fly, Megaselia Halterata (Diptera, Phoridae), R. M. Pfeil, R. A. Walsh, R. O. Mumma

Scanning Microscopy

The antennae, palps, and mouth parts sheath of Megaselia halterata (Wood) (Diptera, Phoridae) were examined by scanning electron microscopy to locate putative olfactory sensilla (POS). Most POS were found on the third antenna! segment (Johnston's organ). These POS included a lanceolate peg, a bulbous peg, and two types of pit sensilla. Female flies could be distinguished from males by the predominance of the lanceolate peg on the female Johnston's organ. One type of pit sensillum with a single exterior opening was located below the cuticular surface and housed several pegs. The other type of pit sensillum was domed with a …

The Microvasculature Of Human Infant Oral Mucosa Using Vascular Corrosion Casts And India Ink Injection Ii. Palate And Lip, Q. X. Yu, K. M. Pang, W. Ran, H. P. Philipsen, X. H. Chen

Scanning Microscopy

The microvasculature of human hard and soft palate and lip originating from four infant males and six females, aged 6 months to 2 years was studied by scanning electron microscopy of vascular corrosion casts and light microscopy of India ink injected specimens. The capillary loops of the hard palate mucosa and vermilion border of the lips were found to be tall, numerous and consisted of primary, secondary and tertiary loops. Those of the soft palatal and labial mucosa were short, few in number and demonstrated a simple hair-pin shape originating directly from the subpapillary vascular network. It was concluded that …

The Microvasculature Of The Larynx: A Scanning Electron Microscopic Study, Peter Franz, Seyedhossein Aharinejad

Scanning Microscopy

In ten adult guinea pigs, the microvascular architecture of the larynx was evaluated using microvascular corrosion casts and scanning electron microscopy. The vocal cords were provided with a subepithelial capillary network. The capillaries, freely anastomosing with each other, were supplied and drained via strongly undulating arteries and veins. The undulation of the latter vessels may explain their adaptability to volume changes of the larynx during phonation. The vasculature of the internal perichondrium of the thyroid cartilage was interrupted at the anterior commissure where an avascular zone was present at the origin of the vocal cords. This avascular area is common …

Induction Of Selective Inner Hair Cell Damage By Carboplatin, S. Takeno, R. V. Harrison, R. J. Mount, M. Wake, Y. Harada

Scanning Microscopy

Carboplatin (diammine [1,1 cyclobutane dicarboxylato (2)-0,0'] platinum) is an anti-cancer agent which can be toxic to the inner ear. We have explored the nature of this ototoxicity in the chinchilla. In this species, initial degenerative changes appear to be restricted to the inner hair cell (IHC) regions of the organ of Corti. This finding is intriguing and unusual since all other known ototoxic drugs, such as aminoglycosides, are predominantly associated with outer hair cell damage.

In the present study, the mechanism of ototoxicity was investigated by comparing two different routes of carboplatin administration. Carboplatin was administered either intravenously (i.v.) or …

Ultrastructural Observations Of The Argonaut Shell, P. R. Mitchell, P. P. Phakey, W. A. Rachinger

Scanning Microscopy

An examination of the ultrastructure of the shell of the cephalopod Argonauta Nodosa was carried out using scanning electron microscopy, transmission electron microscopy and polarised light microscopy. The structure of the Argonaut shell was found to consist of an inner and outer prismatic layer separated by a thin central zone which was sparsely occupied by spherulitic crystals. Fluctuations in the width and porosity of the central zone resulted in changes in the shell's opacity and gave rise to the fibrous lines visible in the structure. The central zone was the region of initial growth and was the nucleating point for …

Calcium Phosphate In Aspergillosis Of The Maxillary Sinus, Hidekuni Tanaka, Toshiro Sakae, Hiroyuki Mishima, Hirotsugu Yamamoto

Scanning Microscopy

The unique appearance of apatite in fungus balls of aspergillosis in the maxillary sinus was investigated using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), X-ray microdiffraction and Fourier transform infrared spectroscopy (FT-IR). Rod-shaped fragments with tubular structures, and globular vesicles covered with conidia were observed in the fungus balls. Massive fragments of a solid substance were demonstrated inside the fungus balls. Calcium and phosphate were detected in necrotic areas of the fungus balls by EDS. X-ray microdiffraction and FT-IR showed the presence of an apatite-like substance, but failed to demonstrate the presence of calcium oxalate crystals usually found in such …

Migration Of Epithelium During Phenytoin-Dependent Gingival Overgrowth In Mice, S. H. Ashrafi, B. Atassi, R. Erickson, T. Sabet

Scanning Microscopy

A small cavity was made in the mesiopalatal area of the maxillary first molar adjacent to the gingiva. Mice were maintained on 40 mg/kg phenytoin (or on diluent for control) by daily intraperitoneal injections. After 9 weeks, light microscopic observations revealed that in experimental mice, epithelial cells migrated towards the cavity and covered it. In controls, epithelial cell migration towards the cavity did not occur. For scanning electron microscopic (SEM) studies, specimens were fixed in 4% glutaraldehyde in 0.1 M phosphate buffer, pH 7.2, for 2 hours, dehydrated, critical point dried and coated with gold. The surface of the outer …

A Simple Empirical Calibration Of Energy Dispersive X-Ray Analysis (Edxa) On The Cornea, N. F. Schrage, K. Benz, P. Beaujean, W. -G. Burchard, M. Reim

Scanning Microscopy

Monitoring of the corneal electrolyte content is important for the study of chemical eye burns. This paper describes quantitative measurements on gelatin standards, corneas and a cornea homogenate with an energy dispersive X-ray analyzer (EDX) in the scanning electron microscope (SEM). Ten micrometers thick cryosections were freeze-dried and mounted on solid carbon supports. The applied quantification procedure was a local peak background analysis with a specifically designed computer program. Similar chemical and physical properties of gelatin, cornea homogenate, and cornea were proven by EDX-analysis and wet chemical analysis. Gelatin standards with known concentrations of different added salts showed linear correlations …

Rabbit And Human Non-Keratinising Stratified Squamous Oesophageal Epithelium Displays Similar Microridge Structure By Scanning Electron Microscopy, S. Shasha'a, G. R. Dickson, R. St. C. Gilmore, G. C. Crean, M. M. Butt, K. E. Carr

Scanning Microscopy

Since the oesophageal epithelium of common laboratory animals, rats and mice, is keratinized it is unsuitable for comparison with typical non-keratinized stratified squamous human epithelium. It is thus important to find a suitable animal model for the study of human oesophageal tissue changes. This study investigated the microridge structure of immature and adult rabbit specimens, and adult human biopsies by scanning electron microscopy and morphometry. The investigation revealed a similarity between typical squamous human and adult rabbit oesophageal mucosal epithelium. While human epithelium specimens subdivided into two other groups (non-typical squamous and non-squamous); all typical squamous human biopsies were from …

Contributions Of Electron Microscopy To The Study Of The Hypertrophic Scar And Related Lesions, C. Ward Kischer

Scanning Microscopy

Prior to 1969, only one study of the hypertrophic scar had been done using electron microscopy, and that one used electron diffraction. Since that time, studies using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) have been integral in establishing not only the characteristics of this lesion but in formulating the reasons why the scar develops and how it resolves. The first SEM studies demonstrated a homogeneous, dense dermal matrix which supported the conclusion that the hypertrophic scar and keloid reflected excess collagen. These same studies were integral in identifying the collagen nodule as the basic anatomical unit of …

Observations On The Enamel Of Odontomas, Carla Marchetti, Cesare Piacentini, Paolo Menghini, Marcella Reguzzoni

Scanning Microscopy

The morphological study of odontomas provides an alternative model for observing the formation of dental tissues, since different maturing stages are present simultaneously. Investigations were performed on decalcified samples (using light microscopy and transmission electron microscopy) and on undecalcified samples of complex odontoma enamel (using transmission electron microscopy). Simultaneous presence of prismatic enamel at various maturing stages with different structural characteristics was observed. Such enamel was sometimes associated with layers of ameloblastic cells with characteristics of cells in functional activity. In other sites, the enamel did not present a prismatic structure but it appeared as unstructured material clusters with abundant …

Scanning Electron Microscopy Of Human Esophageal Mucosa In Patients With Carcinoma Of The Esophagus, M. Cwikiel, M. Q. Yang, M. Albertsson, C. -H. Håkansson, M. Palmegren

Scanning Microscopy

Specimens taken at surgery from 15 patients with carcinoma of the esophagus were examined with scanning electron microscopy. Nine patients were treated with chemotherapy (cisplatin + 5-fluorouracil), surgery and radiotherapy; one received preoperative radiotherapy only; and the remaining five primary surgery only. Scanning electron microscopy was performed on specimens of both tumor tissue and the mucosa at least 5 cm from the tumor. In adjacent non-tumor tissue, damage due to treatment was observed in the form of changes in microridges and increased cell loss. In tumor tissue, the degree of damage was correlated to tumor response to treatment. For patients …

Characterization Of The Complex Sulfide Ore Of Sotiel (Spain) By Scanning Electron Microscopy And Electron Microprobe Analysis, Giuseppe Bonifazi, Roberto Gorga

Scanning Microscopy

This study complements a more exhaustive examination on the complex sulfide mineralization of Sotiel, (Spain), by optical microscopy and multispectral digital analysis of images. Electron microscopy analyses were carried out to document specific associations which are difficult to detect with conventional optical microscopy. This study utilizes the application of digital techniques to image processing, in an attempt to define microstructural and microtextural characteristics of the ore, since they play an important role in the subsequent beneficiation operations (i.e., flotation).

Scientific and economic information bound to complex metallogenic phenomenology and referred to particular paragenetic scenes was acquired by the study in …

Scanning Electron Microscopic Examination Of Intracanal Wall Dentin: Hand Versus Laser Treatment, H. E. Goodis, J. M. White, S. J. Marshall, G. W. Marshall Jr.

Scanning Microscopy

Conventional cleaning and shaping of root canal spaces involves the use of hand and rotary instruments with irrigation. The procedure results in the formation of a smear layer consisting of dentin shavings, organic tissue remnants and microorganisms. The laser has been suggested as an aid in root canal preparation. In this study, pulsed and continuous wave 1.06 μm wavelength Nd:YAG lasers were used to compare their abilities to clean and shape root canal spaces to conventional methods. After preparation, the test teeth were sectioned longitudinally and examined by scanning electron microscopy. The results demonstrated that the laser was capable of …

Three-Dimensional Cytoskeletal Structures Of The Chinchilla Organ Of Corti: Scanning Electron Microscopy Application Of The Polyethylene Glycol Method, A. Nagasawa, R. V. Harrison, R. J. Mount, Y. Harada

Scanning Microscopy

We describe the application of a polyethylene glycol (PEG) embedding technique to examine the sensory and supporting structures of the inner ear. The chinchilla organ of Corti was exposed by cracking PEG embedded cochleas. A range of PEG molecular weights (2000-8000) were utilized; PEG 2000, with a melting point of 57°C was preferred. After removal of the PEG, the three-dimensional aspects of intracellular structures were observed using scanning electron microscopy. Filamentous elements in the hair cell cuticular plate and in the supporting cells were clearly observed, as was the mesh work of cross-linked actin filaments in the cuticular portion of …

Sample Preparation Techniques For Conventional And High Resolution Scanning Electron Microscopy Of The Central Nervous System. The Cerebellum As A Model, Orlando J. Castejon

Scanning Microscopy

In the present paper some basic sample preparation techniques for scanning electron microscopy of nervous tissue are described. These basic preparative methods include conventional scanning electron microscopy or slicing technique, ethanol-cryofracturing technique, freeze-fracture method using either liquid nitrogen (slow freezing) or Freon 22 cooled by liquid nitrogen (fast freezing), improved freeze-fracture method with delicate specimen preparation and chromium coating, ultrasonic microdissection, and "creative tearing" technique. Some basic principles, advantages and limitations are critically considered. In addition, some specific applications in neurobiological research are reported. Emphasis is placed upon understanding the sources and nature of artifacts that are likely to be …

Scanning Electron Microscopy Of 2,8-Dihydroxyadenine Crystals And Stones, P. Winter, A. Hesse, K. Klocke, R. M. Schaefer

Scanning Microscopy

The lack of purine salvage enzyme, adenine phosphoribosyltransferase (APRT), leads to 2,8-dihydroxyadenine stone formation and/or crystalluria because it is insoluble in urine. Urolithiasis composed of 2,8-dihydroxyadenine is not only formed in a complete defect of APRT, but also in a partial deficiency of this enzyme. The defect is inherited as an autosomal recessive trait, the homozygous state is associated with high urinary levels of 2,8-dihydroxyadenine and with crystalluria, calculus formation, and potential nephrotoxicity. Determination of the APRT activity will facilitate quantification of the enzyme deficiency and elucidation of the hereditary history. 2,8-dihydroxyadenine excretion in the 24-hour urine and its circadian …

Casting With Mercox-Methylmethacrylic Acid Mixtures Causes Plastic Sheets On Elastic Arteries. A Scanning And Transmission Electron Microscopic Study, Seyedhossein Aharinejad, Peter Böck

Scanning Microscopy

Lungs and systemic vessels of rats were cast with Mercox, both undiluted and diluted with monomeric methylmethycrylate (MMA; v:v/4:1), and studied by scanning electron microscopy (SEM). A sheet, less than 5 μm thick, surrounded the surface of cast pulmonary arteries and the aorta, when using diluted Mercox. This envelope was absent when casts were prepared with undiluted Mercox. Transmission electron microscopy (TEM) of unmacerated cast arteries showed all constituents of the vascular wall. Sections of thoroughly macerated vascular casts, however, still showed elastic lamellae in the vascular wall region, whereas muscular components and endothelial lining were completely digested. It is …