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PubMed1983

Surface morphology and membrane phenotype of cultured human leukemia-lymphoma cells. A scanning electron microscopic study of 36 cell lines.

Scanning electron microscopy and immunologic methods, to detect the expression of a variety of surface markers, were performed on cells from 36 established human leukemia-lymphoid cell lines. Attempts were made to correlate the surface morphologic findings with the membrane phenotype as determined by the presence or absence of a number of specific antigens and B- or T-cell markers. Thirteen of the cell lines were of the T-lymphoid type, 15 B-derived, and eight were defined as non-B non-T in nature. All the lines derived from patients with acute lymphoblastic leukemia (ALL) had similar surface topographies and generally displayed relatively smooth surfaces with few microvilli, while in some a proportion of moderately villous cells was evident. Burkitt's lymphoma cells tended to show more villous surfaces but, similar to circulating B-ALL cells, variable numbers of microvilli were frequently seen making consistent distinctions between this and other lymphoid leukemias difficult in individual cases. Two of the non-B non-T lines are known to be of erythroid (K-562) and myeloid origin (HL-60), respectively. In both these lines, cells with relatively few microprojections dominated; however, some showed transverse ridge-like profiles, a feature frequently encountered on circulating leukemic cells of myeloid type.

B-Lymphocytes↗
PubMed1976

Surface morphology of human aorta as revealed by the scanning electron microscope.

Human aorta was prepared for scanning electron microscopy using critical point drying. The aortic surface is lined by a continuous layer of squamous endothelial cells. The luminal surface of these cells contains many microvilli or microappendages and pinocytotic vesicles. In addition, at the periphery of each cell, larger marginal appendages or microfolds are present which allow the observer to see the cell boundaries clearly. The marginal folds are superficial to the cell junctions and could be observed without any staining procedures. These observations on human aorta are generally in agreement with our findings on the rabbit and guinea pig aorta and vena cava but in contrast to others who have reported the presence of ridges, intercellular bridges, and "hair-like" processes on the endothelial surfaces.

Aorta↗
PubMed1997

Scanning electron microscopic study of primary fracture healing.

Scanning electron microscopy was used to study primary bone healing. This technique, essential for a three-dimensional description, has provided excellent visualization and revealed new aspects of the micromorphology of primary bone healing. Calcifying collagen bundles were responsible for the first mechanical stability, bone healing took place later in fracture vaults generated by compressed fracture fragments which were partially nonvital. A direct bridging of the fracture fragments by sprouting osteons was not observed.

Animals↗
PubMed1980

[A scanning electron microscope study of the fine angioarchitecture of "punctation" and "atypical vessels" (author's transl)].

The present study was aimed to evaluate the correlation of histologic findings with colposcopic findings of "punctation" and "atypical vessels". The stereoscopic angioarchitectures of "punctation" and "atypical vessels" were observed clearly by scanning electron microscope, utilizing cast formation technique of blood vessels on hysterectomy specimens. Scanning electron microscopy revealed following characteristic findings. 1) The angioarchitecture of "punctation" is composed of three strata. (a) subepithelial capillary network, (b) capillaries rise into the stromal papillae from subepithelial capillary network. (c) stromal vessels ending in subepithelial capillary network. 2) Stratum (b) is observed as "punctation" on colposcopy. 3) Stratum (b) alterate morphologically as follows; hairpin-like capillaries correspond to "punctation" in inflammation, gathered & twisted hairpin-like capillaries in dysplasia, asparagus-like vessels in C.I.S., cauliflower-like vessels in early invasive cancer, respectively. 4) The mesh of stratum (a) become denser as the lesions advance, and in early invasive cancer, the destruction of stratum (a) begin to appear. 5) The branchings of stratum (c) increase as the lesions advance. 6) Chaotic angioarchitecture is observed in invasive cancer, with complete destruction of stratum (a). 7) The morphologic alteration of stratum (b) is the most remarkable in three strata. Colposcopically, these alterations of angioarchitecture are observed as follows; in "punctation", "red spot" become larger and irregularity increase both in size, shape and arrangement, as the lesions advance, in "atypical vessels", "vascular pattern" increase irregularity both in shape, caliber, continuation and arrangement. As a result, by analysing these scanning electron microscopic pictures and comparing them with their colpophotographs and histologic findings, it can be emphasized that, it might be possible to make histologic diagnosis merely by colposcopy.

Capillaries↗
PubMedDate not supplied

The myenteric plexus of the rat colon: a methodological approach for scanning electron microscopical study.

In the present research four different procedures were tested for the Scanning Electron Microscopic identification of Auerbach's myenteric plexus in the distal colon of the rat. The specimens were processed as follows: enzymatic and chemical digestion (trypsin and HCl); fixation with glutaraldehyde; fixation and staining with zinc iodide/osmium tetroxide (ZIO); fixation and staining with zinc iodide/osmium tetroxide (ZIO) followed by maceration in NaOH solution. All the procedures required microdissection to separate the different layers of the colonic wall. Light microscopic controls were prepared with the ZIO technique. Among the methods utilized, fixation and staining with ZIO appeared to be by far the best as regards the preservation of the architectural arrangement of the myenteric plexus as well as of the fine structural details.

Animals↗
PubMed1994

Luminal epithelium of Warthin's tumours: a scanning electron microscopic study.

Three cases of papillary cystadenoma lymphomatosum were examined by light and scanning electron microscope to declare the morphology of the luminal epithelial surface. It was found that ciliated cells were present in one case. This finding explains the origin of ciliated cells as a development included in the neighbouring lymph node with a tendency of metaplastic change and exfoliation.

Adenolymphoma↗
PubMed1997

Immuno-scanning electron microscope characterization of large tubules in human deciduous dentin.

BACKGROUND: This study was undertaken to elucidate the type and origin of collagen fibrils which construct the large tubules in deciduous coronal dentin by scanning electron microscope and anti-types I and III collagen antibody procedures. METHODS: The studies were performed on human deciduous teeth. The teeth were fixed in 4% paraformaldehyde solution and then fractured either mesio-distally parallel to the long axis of the tooth or transversely perpendicular to the long axis of the tooth crown. The specimens were three-dimensionally observed employing the scanning electron microscope to distinguish the content of large tubules. Polyclonal antibodies of anti-type I and anti-type III collagen with 20 nm colloidal gold, and secondary electron imaging and backscatter electron imaging of high-resolution field emission scanning electron microscopy were used to examine the types of collagen fibrils. RESULTS: The large tubules extended from the vicinity of the incisal edge of the dentino-enamel junction to the pulp cavity. Inside the large tubules, fibers in compact bundles run parallel to the longitudinal axis of the tubules. The fiber bundles consisted of collagen fibrils which were 50-150 nm in diameter with typical cross striation. Immuno-scanning electron microscopy showed type I collagen-labelling gold particles and type III collagen-labelling gold particles to be abundant on the fibrils. Types I and III collagen-labelling gold particles were present on the banded collagen fibrils regardless of their diameter. CONCLUSIONS: It was found that type III collagen is present together with type I collagen on the fibrils constructing the large tubules of the human deciduous dentin. This immunohistochemical study suggested that the fibrils constructing the large tubules were derived from the von Korff fibers, and types I and III collagens formed copolymers.

Child↗
PubMed1989

[Scanning electron microscopic observation on odontogenic keratocysts].

Five odontogenic keratocysts were examined by using a scanning electron microscope (SEM) on the three-dimensional ultrastructure of epithelial lining cells. The fractured surface of the specimens showed a single row of columnar or cuboidal cells perpendicular to the flat basal lamina, a four- to five-cell layer of spinous cells, and a superficial layer of flattened parakeratinized cells. At high magnification of superficial cell surface, microvillis, short discontinuous branched or anastomosing microridges were observed.

Humans↗
PubMed1986

Scanning electron microscopic studies of the membranous labyrinth after transtympanic infusion of local anesthetics (lidocain).

Scanning electron microscopic observation of the transtympanic infusion of 10% xylocain revealed twisting and disorders of outer hairs especially from the 2nd and 3rd rows of the basal to the 2nd turn of the organ of Corti, and adhesion and fusion of the sensory hairs of the crista ampullaris and otolith organ 1 and 4 days after injection. Four percent xylocain however demonstrated very minor alteration of the sensory hairs and no missing sensory hairs were detected from any cases. The authors hypothesized from electron microscopic observation that adhesion and fusion of vestibular sensory hairs or twisting and disorders of the sensory hairs of the organ of Corti might act to intercept harmful circulation of exclusion of abnormal excitement of hair cells and the innovation of electrical discharge of sensory hairs due not only to the pharmacological effects of xylocain but also to osmotic pressure.

Animals↗
PubMed1978

Scanning electron microscopic studies on cultured heart cells after the induction of arrhythmias and fibrillation.

Scanning electron microscopic observations were made of mouse embryonic heart cells in culture to clarify the interrelationship between morphological damage and cardiac arrhythmias and fibrillation induced by changes of ion concentrations. They were studied with particular reference to the abnormalities in the heart cell and the intercellular connections. The cells exhibited arrhythmias with any alteration in ion concentration (MgSO4, CaCl2, KCl, NaCl) in the culture medium, and they developed fibrillation-like beating under certain conditions of lowered potassium, or sodium, and increased sodium with a reduction in calcium or potassium. The heart cells showing arrhythmias were revealed by scanning electron microscopy to have more or less fine morphological changes in their slender processes, and detached or raised cell edges. Fold-like undulations in the cell body and cell ledge were also numerous in cells exhibiting fibrillation-like beating. These cell body changes may, however, be characteristic of cells maintained in cultures with lowered potassium content, since only these cultures showed such changes. Changes of cell ledge were also demonstrable in cultures with altered MgSO4, CaCl2 content or increased KCl or NaCl content although the cells in these cultures did not develop fibrillation. It was noted that there was a tendency for the changes of cell body and cell edge to be conspicuous in cells exhibiting fibrillation. The results obtained indicated that fibrillation developed only in the presence of altered concentrations of certain ions, in association with subtle morphological changes in the cells and intercellular connections.

Arrhythmias, Cardiac↗
PubMed1991

Scanning electron microscopic study of odontoblasts and circumpulpal dentin in a human tooth.

Two combined scanning electron microscopic methods including modified fixative procedures were used for studying the morphologic aspects of the odontoblasts and the corresponding dentinal wall at different endodontic levels. The odontoblasts were tightly packed in the pulp horn, where they assumed pear-shaped profiles and, from crown to apex, successively looked spindle shaped, club shaped, and globular. Their number decreased in the pulp radicular portion, where the interglobular spaces were enlarged. The filling fibrillar material varied from crown to apex. A globular circumpulpal dentin was observed at all levels of the root canal. The tubule openings varied in number and size.

Adult↗
PubMed1975

Scanning electron microscopic observations of common carotid artery endothelium in the rat. II. Sutured arteries.

Scanning electron microscopic findings in 26 rats with sutured 1 to 1.2 mm segments of carotid artery indicate a difference in morphological changes beneath clamped areas and areas 2 to 3 mm adjacent to the suture line. Craters similar to those observed in control specimens were seen beneath clamped sites without significant platelet aggregation or platelet adherence to the endothelial wall. In contrast, areas adjacent to the suture line exhibited a pattern of fibrin and platelet adherence to the vessel endothelial wall. These changes appeared to be consistent after one to four hours of observation in most animals. Sutures, although attracting some platelets, did not exhibit platelet and fibrin adherence as marked as that of the adjacent endothelial wall.

Animals↗
PubMed1975

The distal ommatidium of the compound eye of the housefly (Musca domestica): a scanning electron microscope study.

The distal aspect of the housefly ommatidium was surveyed by the scanning electron microscope. Attention was directed to the somal eminence of the superior central cell and the lens to large pigment cell junction. The underside of each lens facet exhibits six hexagonally arranged incisures. Into each of these indentations are fitted several large pigment cells. This hexagonal indentation appears to be a tenacious anchorage. Two corneal pigment cells laterally encircle the pseudocone and at their proximal extension they enclose the Semper cells and neck of the retinula. The somal eminence of the superior central cell is about 10 mum from the base of the corneal pigment cell enclosure. Micrographs were used to construct a diagram of the ommatidium above the basement membrane. Suggestions are made as to the functional correlates of the observed ommatidial structures.

Animals↗
PubMed1992

Selenite nuclear cataractogenesis: a scanning electron microscope study.

The sequential changes during selenite nuclear cataractogenesis were examined with a scanning electron microscope (SEM) and correlated with slit lamp observations. A posterior opacity, visible with the slit lamp 1-2 days after injection of sodium selenite, was found to consist of masses of vacuoles in the superficial posterior cortex by SEM. 2-3 days post injection, a biomicroscopic refractile ring around the nucleus was represented by SEM abnormalities suggesting membrane damage and possible loss of cytosol in the perinuclear region. All normal structure in this region was lost by 5 days after injection when the central nucleus had become opaque. SEM also showed evidence for damage in areas which were still clear by slit lamp examination. Changes, characteristic of aging, were found near selenite induced damage in peripheral (younger) fibers.

Animals↗
PubMed1981

[Effect of prodigiozan on the surface structures of peritoneal macrophages under the scanning electron microscope].

The surface structures of peritoneal macrophages of mice were investigated with a scanning electron microscope RZEM-500. The study revealed 3 types of the macrophages. Macrophages of type 1 predominated in intact mice. These macrophages are cells rounded or oval in shape with a great number of compact finger-like excresences differing in size and form. In the animals treated with prodigiozan in a single dose of 150 mg/kg, the majority of the macrophages were larger in size and had a changed surface: spread, with many branches, "train", undulated membranes. Formation of a great number of macrophagal and macrophagal-lymphocytic clusters evident of the increased cell cooperation under the effect of prodigiozan was shown. The morphological changes in the surface structures of the macrophages under the effect of prodigiozan in vivo indicate an increase in their functional activity.

Animals↗
PubMed1984

Three-dimensional architecture of cerebral microvessels with a scanning electron microscope: a cerebrovascular casting method for fetal and adult rats.

Vascular casting for scanning electron microscopic studies on microvascular architecture is in common use for various visceral organs in the field of anatomy. However, only a few studies have been performed on the brain using the previously reported casting method, and no detailed descriptions deal with suitable methodology for producing brain vascular casts. Our casting method, introduced here, for the CNS from the fetal to the adult stage involves the following modifications: (1) Perfusion fixation of the brain is carried out before injecting the plastic resin for casting into the cerebral blood vessels; (2) digestion of nervous tissue is accomplished with a sodium hydroxide and sodium hypochlorite solution; and (3) vascular casts are dried by a freeze-drying method, while the nondigested brain slices opposite the casts can be investigated with light microscopy and transmission electron microscopy. This modified casting method enables one to represent the microvascular system of the rat brain three-dimensionally from embryonal day 17 onward. It is hoped that this method will prove to be a useful tool in morphological vascular research on the nervous system.

Animals↗