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PubMed1994

Comparative studies of the same adenocarcinoma cells, macrophages, and mesothelial cells by light microscopy, scanning electron microscopy, and transmission electron microscopy.

The identification of cells in body cavities of cancer patients is sometimes difficult to make. In order to make a definite cytological diagnosis, we observed the same cells by using light microscopy (LM)-scanning electron microscopy (SEM)-transmission electron microscopy (TEM). In this study we first stained cells by the Papanicolaou method after fixation in 1% glutaraldehyde for LM, and then attempted to observe them successively by SEM-TEM after fixation in 1% paraformaldehyde and 1.25% OsO4. Our method and procedures in examining successively one and the same cells in body cavity fluids by using LM, SEM, and TEM ensured accurate discrimination among adenocarcinoma cells, mesothelial cells, and macrophages. The results of this study suggest that LM-SEM-TEM may be of diagnostic value in distinguishing among mesothelial cells, macrophages, and adenocarcinoma cells. This method also succeeded in disclosing differences between the ultrastructure of the cell surfaces, and those of the cytoplasm, and of the nuclei. It is desirable that LM-SEM-TEM observation can be introduced into various aspects in order to obtain an improvement in the diagnosis by cytologic examination, the judgment of therapeutical effects, drug selection, and prognostic presumption.

Adenocarcinoma↗
PubMed1979

Morphological studies of the spleen in idiopathic portal hypertension (so-called Banti's syndrome without liver cirrhosis) using light microscopy, scanning electron microscopy and histometry.

Morphological changes in the spleens of patients with idiopathic portal hypertension (IPH) were studied and compared with the normal spleen. The study used (1) light microscopy with histometry, (2) scanning electron microscopy (SEM) of the splenic tissue with histometry and (3) SEM of the spleen vascular replica. Histometrical studies by light microscopy showed that the volume of red pulp of IPH was increased in a unit area and to a total of 12 times the normal in the whole spleen. The white pulp was scanty of lymphocytes and decreased in a unit area but it was increased in the whole spleen. SEM of the white pulp of IPH demonstrated many channels formed by reticulum cells and running parallel with each other along the central artery. This finding presumably corresponds to periarterial fibrosis in light microscopy. SEM histometry demonstrated that the venous sinuses of IPH were small but increased in number and occupied the same percentage area in a unit red pulp area as in the normal spleen. The Billroth cord of IPH was narrowed and occupied by thickened reticulum cells, which may cause increased pooling and destruction of blood cells in the enlarged spleen (hypersplenism). SEM of the tissue and vascular replica demonstrated open arterial termination in the Billroth cord in the spleen of IPH as well as in the normal spleen. Venous sinuses in the replica of IPH ran parallel with each other forming bundles with fewer intercommunications than normal.

Adult↗
PubMed2003

Application of high-angle annular dark field scanning transmission electron microscopy, scanning transmission electron microscopy-energy dispersive X-ray spectrometry, and energy-filtered transmission electron microscopy to the characterization of nanoparticles in the environment.

A major challenge to the development of a fundamental understanding of transport and retardation mechanisms of trace metal contaminants (<10 ppm) is their identification and characterization at the nanoscale. Atomic-scale techniques, such as conventional transmission electron microscopy, although powerful, are limited by the extremely small amounts of material that are examined. However, recent advances in electron microscopy provide a number of new analytical techniques that expand its application in environmental studies, particularly those concerning heavy metals on airborne particulates or water-borne colloids. High-angle annular dark field scanning transmission electron microscopy (HAADF-STEM), STEM-energy-dispersive X-ray spectrometry (EDX), and energy-filtered TEM (EFTEM) can be effectively used to identify and characterize nanoparticles. The image contrast in HAADF-STEM is strongly correlated to the atomic mass: heavier elements contribute to brighter contrast. Gold nanocrystals in pyrite and uranium nanocrystals in atmospheric aerosols have been identified by HAADF-STEM and STEM-EDX mapping and subsequently characterized by high-resolution TEM (HRTEM). EFTEM was used to identify U and Fe nanocrystals embedded in an aluminosilicate. A rare, As-bearing nanophase, westerveldite (FeAs), was identified by STEM-EDX and HRTEM. The combined use of these techniques greatly expands the effective application of electron microscopy in environmental studies, especially when applied to metals of very low concentrations. This paper describes examples of how these electron microbeam techniques can be used in combination to characterize a low concentration of heavy metals (a few ppm) on nanoscale particles.

Electron Probe Microanalysis↗
PubMed1986

Assembly of chromatin fibers into metaphase chromosomes analyzed by transmission electron microscopy and scanning electron microscopy.

The higher-order assembly of the approximately 30 nm chromatin fibers into the characteristic morphology of HeLa mitotic chromosomes was investigated by electron microscopy. Transmission electron microscopy (TEM) of serial sections was applied to view the distribution of the DNA-histone-nonhistone fibers through the chromatid arms. Scanning electron microscopy (SEM) provided a complementary technique allowing the surface arrangement of the fibers to be observed. The approach with both procedures was to swell the chromosomes slightly, without extracting proteins, so that the densely-packed chromatin fibers were separated. The degree of expansion of the chromosomes was controlled by adjusting the concentration of divalent cations (Mg2+). With TEM, individual fibers could be resolved by decreasing the Mg2+ concentration to 1.0-1.5 mM. The predominant mode of fiber organization was seen to be radial for both longitudinal and transverse sections. Using SEM, surface protuberances with an average diameter of 69 nm became visible after the Mg2+ concentration was reduced to 1.5 mM. The knobby surface appearance was a variable feature, because the average diameter decreased when the divalent cation concentration was further reduced. The surface projections appear to represent the peripheral tips of radial chromatin loops. These TEM and SEM observations support a "radial loop" model for the organization of the chromatin fibers in metaphase chromosomes.

Calcium↗
PubMedDate not supplied

[A comparison between phase-contrast optical microscopy and scanning electron microscopy for the analysis of air-borne asbestos fibers in an office environment].

There is no general agreement on the relationship between results obtained by optical microscopy (PCOM) and electron scanning microscopy (SEM) or electron transmission microscopy (TEM) for airborne asbestos fibres. However, a considerable amount of data has been produced in latter years indicating that a general correlation factor, not differing greatly from unity, can be established between the two analytical techniques if counts are limited to fibres longer than 5 microns. A study was made of the relationship between SEM and PCOM when used simultaneously for determination of background concentrations of asbestos in office buildings. Twenty-four couples of samples were collected in parallel for PCOM and SEM in different locations distributed over the various floors of two buildings containing amosite sprayed on structural parts. Asbestos and total fibre counts by SEM were performed following the Verein Deutscher Ingenieure (VDI) method 3492. For total fibre counts the European PCOM method was mainly used. Discrimination of asbestos from non-asbestos fibres was performed using criteria based on birefringence and morphological characteristics of fibres. Counts included only those fibres longer than 5 microns, diameter less than 3 microns and aspect ratio greater than 3. Both total fibres and asbestos fibres were recorded separately by PCOM and SEM. the arithmetic and geometric means of the ratio between PCOM and SEM were 1.3 and 1.1 respectively for total fibres and 1.2 and 1.1 for asbestos fibres (excluding one outlying value). The regression study showed a significant linear correlation (P = 0.01) with correlation coefficients of 0.84 for asbestos fibres and 0.52 for total fibres.

Air Pollution, Indoor↗
PubMed1990

Correlative light microscopy, scanning electron microscopy, and transmission electron microscopy of osmium-macerated biological tissues.

A method facilitating correlation of light microscopic (LM), scanning electron microscopic (SEM) and transmission electron microscopic (TEM) images was developed. Rat kidney and heart were initially subjected to the osmium maceration procedure and then embedded in acrylic resin. Semithin sections of the tissue blocks were first provided for LM and then examined by SEM after resin removal. Furthermore, the ultrathin sections adjacent to the semithin sections were observed by TEM. The three-dimensional images of intracellular organelles provided an informative adjunct to LM and TEM.

Animals↗
PubMed2002

[Morphogenesis of media calcinosis in Mönckeberg disease. Light microscopy, scanning electron microscopy and roentgen microanalysis findings].

OBJECTIVE: In contrast to granular mediacalcinosis of the aorta, Mönckeberg's disease is characterized by the occurrence of sheet-like calcification. It is usually said that the pathogenesis of this calcification is unknown. MATERIAL AND METHODS: To obtain some insight into the mechanism leading to this calcification, we performed light microscopic, scanning electron microscopic and X-ray microanalysis investigations on femoral arteries from autopsies. RESULTS: By light microscopy preferentially sheet-like calcifications of different size appeared. In the alizarin red S stain in the neighborhood of these compact structures calcified globules were observed. By SEM in the neighborhood of the compact areas calcified granules were found; the compact structures themselves consisted of granules sticking one onto the other. X-ray microanalysis exhibited high contents of calcium and phosphorus in the compact calcifications; they also showed a minor content of magnesium. Isolated granules inside the compact calcifications showed a nearly identical composition, while granules outside in the surrounding media consisted preferentially from calcium and phosphorus, but they exhibited a slight higher magnesium content. CONCLUSIONS: It is concluded that Mönckeberg's media calcification is due to dystrophic calcification. Calcified matrix vesicles from necrotic cells, as it is assumed for the pathogenesis of the calcification of arteriosclerotic plaques (31), are interpreted as precursors of the solid calcifications which may develop by confluence and sticking one onto the other of calcified globules.

Aged↗
PubMed1980

Light microscopy, scanning electron microscopy, and microprobe analysis of bone response to zinc and nonzinc amalgam implants.

Freshly mixed, unset zinc-free and zinc-containing analgam was implanted in the right tibia of 32 rats. Half of the specimens were examined by the light microscope and the other half by the scanning electron microscope and x-ray microprobe analysis. It was found that amalgam is well tolerated by the rat osseous tissue, and there were no histologic reaction differences between zinc and zinc free amalgam. The surfaces of the implants were covered by an organic film at 3 weeks and with bone at later intervals. Very little corrosion products containing sulfur were observed on the amalgam surface at all intervals. Bone adjacent to the amalgam contained tin and sulfur irrespective of the presence of zinc in the alloy, indicating outward migration of specific components of the alloy.

Animals↗
PubMed1998

Compatibility study between ibuproxam and pharmaceutical excipients using differential scanning calorimetry, hot-stage microscopy and scanning electron microscopy.

Differential scanning calorimetry (DSC) was used as a screening technique for assessing the compatibility of ibuproxam with some currently employed pharmaceutical excipients. The influence of processing effects (simple blending, cogrinding or kneading) on drug stability was also evaluated. On the basis of DSC results, ibuproxam was found to be compatible with corn starch, avicel and sodium carboxymethylcellulose. Some drug-excipient interaction was observed with polyethyleneglycol 4000, palmitic acid, stearic acid, Ca and Mg stearate. Actual solid-phase interactions of the drug with polyvinylpolypyrrolidone and polyvinylpirrolidone K30 were induced by mechanical treatments. Hot-stage microscopy (HSM) and scanning electron microscopy (SEM) were of help in interpreting the DSC results and excluding in all cases relevant pharmaceutical incompatibilities.

Benzeneacetamides↗
PubMed1976

Study on development of Agaricus bisporus by fluorescent microscopy and scanning electron microscopy.

Two strains of Agaricus bisporus have been investigated by fluorescent microscopy and scanning electron microscopy. Somatic nuclei, stained with auramin O and examined by fluorescent microscopy, appear to be randomly distributed, divide asynchronously, and assume a nonclassical or "two-track" configuration during mitotic metaphase. A similar configuration has been observed for nuclei during meiosis, but early meiosis in A. bisporus appears to be classical, usually with nine pairs of chromosomes evident during prophase I. Scanning electron microscopy has been used to document developmental stages in the formation and germination of basidiospores. Two-spored basidia were predominant, but occasionally one- or three-spored forms were observed. Four-spored basidia were absent, and uninucleated basidiospores were exceedingly rare to absent.

Basidiomycota↗
PubMed1987

The infected hairs of tinea capitis due to Microsporum canis: demonstration of uniqueness of the hair cuticle by scanning electron microscopy.

Scanning and transmission electron microscopic studies were done on scalp hairs of four patients infected with ectothrix Microsporum canis. Both freeze fracture and cross-sectioning of hairs revealed a thick sheath of fungal spores encircling the hair shaft beneath an intact cuticle. These spores were not visible on surface inspection but became apparent only where the cuticle had been rubbed off or broken. Daily selenium sulfide shampoos removed all of the spores from these sites. The cuticle is viewed as being an effective barrier to the penetration of fungi, so that the hair is vulnerable to fungus infection only deep within the hair follicle below the level of the mature cuticle. Once the fungus enters the hair cortex just above the hair bulb, it produces myriads of spores that remain trapped and hidden beneath the cuticle for the length of the intact hair.

Child↗
PubMedDate not supplied

Scanning electron microscopy in the study of lung cancer. New technique of comparative studies on the same lung cancer cells by light microscopy and scanning electron microscopy.

A new technique for observing the same lung cancer cells by light microscope and SEM was developed. By this technique it was clarified that the surface ultrastructures of epidermoid carcinoma, adenocarcinoma and oat-cell carcinoma cells are different from each other. Those of adenocarcinoma and mesothelial cells were quite different. This technique might be of use, adding new information into the ordinary cytologic diagnosis of cancer cells.

Adenocarcinoma↗
PubMed1984

Esophageal dysplasia. Assessment by light microscopy and scanning electron microscopy.

This study was performed to determine the characteristics of esophageal dysplasia by scanning electron microscopy. A total of 82 esophageal biopsy specimens were taken from 30 patients who were divided into three groups. Group 1 patients had no known esophageal disease. Group 2 patients had squamous cell cancer. Group 3 patients had esophagitis. Mucosal biopsy specimens that had been diagnosed by light microscopy as normal, esophagitis, or dysplastic mucosa were examined by scanning electron microscopy. A characteristic appearance for each type of mucosa was recognized by scanning electron microscopy. A quantitative analysis of the scanning electron microscopy feature of microridge density showed a statistically significant difference not only between normal and dysplastic mucosa, but also between esophagitis and dysplastic mucosa. The addition of scanning electron microscopy to light microscopy may prove helpful in the diagnosis of dysplasia as well as in the understanding of the biologic behavior of dysplastic cells and possibly their relationship to esophageal carcinoma.

Adult↗
PubMed1999

Discrimination of morphological findings in dentine from osteogenesis imperfecta patients using combinations of polarized light microscopy, microradiography and scanning electron microscopy.

OBJECTIVES: The aim of this study was to investigate the morphological appearance of dentine in teeth from individuals with osteogenesis imperfecta type I, III and IV using different histological techniques, and to correlate morphological findings to different types of osteogenesis imperfecta. SAMPLE AND METHODS: Extracted or exfoliated primary and permanent teeth were collected from 15 patients with the osteogenesis imperfecta diagnoses I, III or IV, with or without the additional diagnosis dentinogenesis imperfecta. Ground and decalcified sections were prepared from the teeth. Histo-morphological studies of the dentine were performed utilizing light and polarized light microscopy, microradiography and scanning electron microscopy. RESULTS: Characteristic findings were irregular tubules, remnants of capillary inclusions and obliterated pulps. All types of osteogenesis imperfecta exhibited similar types of dentine aberrations, but patients with type III or IV had a higher frequency of aberrations when compared to type I. CONCLUSIONS: The combination of either polarized light microscopy or micro-radiography, together with scanning electron microscopy, gave the most amount of morphological information from dentine samples. In addition, aberrations in dentine structure were more clearly observable. Light microscopy was not critical for the analyses.

Adolescent↗
PubMed1981

Topographic examination of sister chromatid differential staining by Nomarski interference microscopy and scanning electron microscopy.

BrdU-substituted Chinese hamster chromosomes were treated with a hog Na2HPO4 solution and stained with Giemsa to produce sister chromatid differential staining (SCD). The process of SCD was examined with the Nomarski differential interference microscope and the scanning electron microscope. After the Na2HPO4 treatment alone, unifilarly BrdU-substituted (TB) chromatids appeared somewhat more severely collapsed than the bifilarly substituted (BB) chromatids. Subsequent Giemsa staining, however, brought about pronounced piling up of the Giemsa dye on the TB-chromatids but not on the BB-ones, causing highly distinct differential Giemsa staining as well as a marked differentiation in surface topography between the sister chromatids. Removal of the Giemsa dye from the differentially Giemsa stained chromosomes resulted in a disappearance of such a pronounced topographic differentiation.

Animals↗
PubMed1983

Scanning electron microscopy and X-ray microanalysis of foreign bodies associated with Silastic implants in humans.

Polydimethylsiloxane (Silastic) capsules containing megestrol acetate have been implanted in subcutaneous tissue as a method of long-term contraception. Histological studies revealed a granulomatous foreign body reaction around these capsules with birefringent crystals in multinucleated giant cells. Although several authors had interpreted these crystals as steroids, this seemed unlikely since the tissue had been processed with organic solvents. Analysis of these crystals by polarization microscopy, scanning electron microscopy, and X-ray microanalysis demonstrated that the material was talc. The talc was probably introduced as a contaminant from gloves during the implantation. Further analysis showed that capsule fragmentation could not have produced the material since Silastic particles could not be detected.

Contraceptive Agents↗