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PubMed2005

[Scanning electron microscopic observation of the fetal stria vascularis].

OBJECTIVE: To get full appreciation of the ultrastructural features in the stria vascularis of human fetal cochlea. METHOD: The Stria vascularis in human fetal cochlea were observed by scanning electron microscope. RESULT: The cells of the fetal stria vascularis present round. All cell surfaces are covered with a thick layer of microvilli. The transition zone is between the stria vascularis and the spiral prominence. The shape of cells gradually changes on the spiral prominence and becomes more irregular. Several cells have a structure of elongated hexagons. The structure of the intermediate cells, basal cells and capillary were also observed from the fractural surface in the stria vascularis. CONCLUSION: The surface structures of the whole stria vascularis were observed by scanning electron microscope, especially the surface appearance of the marginal cells. New information will be provided for understanding the structure and function in the stria vascularis.

Cochlea↗
PubMed1975

Observation of the secretion on the surface of the bronchioles with the scanning electron microscope.

The secretion covering the surface of the bronchioles can be demonstrated with the scanning electron microscope if fixative is introduced into the pulmonary artery or directly into the lung rather than through the trachea. Buffered glutaraldehyde, ethanol, or an ethanol-ether mixture can be used as a fixative. With this method of preparation the surface secretion appears as a smooth coating covering the cilia and cells. The secretion is insoluble in ethanol ether or chloroform methanol, suggesting that there is little lipid contained in it. Reasons are cited for believing that the major component of the secretion is a protein that arises from the Clara cell.

Animals↗
PubMed1993

[Scanning electron microscopic observations on the copulatory spicules of the male Necator americanus and Ancylostoma duodenale].

Scanning electron microscopic observations were made on the morphological structures of the two copulatory spicules of the male Necator americanus and Ancylostoma duodenale. In both species, one of the two copulatory spicules was in the shape of a concave groove and the other, in the shape of an oblate tube. Owing to the difference in the concavity of the groove shaped copulatory spicule between the two species as shown by the cross sections, Necator americanus usually appear to have only one copulatory spicule whereas Ancylostoma duodenale usually show two separate copulatory spicules in appearance (Figs 1-10).

Ancylostoma↗
PubMed1988

Scanning electron microscope studies of Agrobacterium tumefaciens attachment to Zea mays, Gladiolus sp., and Triticum aestivum.

Scanning electron microscope studies demonstrated that cells of Agrobacterium tumefaciens strains attach to cells on the cut surfaces of corn and wheat seedlings and to gladiolus disks. Bacterial cells attached to these monocots in the same manner as they attached to the dicots tested. Of the strains tested, A66 and T37 covered more of the cut surfaces of these monocots in a nonrandom fashion than did cells of other isolates. These bacteria attached to cells of intact monocotyledonous plants and had the greatest affinity for tissues located within the vascular bundles. They attached in large numbers to cells in these areas in all three monocots tested.

Bacterial Adhesion↗
PubMed1977

A scanning electron microscopic study of IAA-induced tumors in bean (Phaseolus vulgaris L.) embryos.

A scanning electron microscopic study of indole-3-acetic acid (IAA) induced tumour in the hypocotyl region of bean embryos shows a distinct morphological, structural and topographical change from the non-treated bean embryos. The IAA-induced tumour surface, in the hypocotyl region, shows distinct cell enlargement, some cellular proliferation in the parenchymatous tissue, total destruction of the epidermis and stomata and some variation in trichome structures. In dole-3-acetic acid inhibits the normal growth of the epicotyl, and, as age progresses, adventitious roots appear all over the surface. When IAA-depletion occurs, epicotyl growth resumes, which indicates that this tumour formation in bean embryos is an IAA-dependent tumour.

Indoleacetic Acids↗
PubMed1983

Scanning electron microscopic study of epiplexus cells in the lateral ventricles of the monkey (Macaca fascicularis).

Scanning electron microscopic study of epiplexus cells in the monkey revealed their diverse morphological forms. These pleomorphic cells were round, bipolar or stellate in shape. Their cell body was smooth or displayed various types of microappendages: microvilli, filopodia, pseudopodia and it was sometimes ruffled. Examination of the ventricular surface of the choroidal epithelium showed that the cell membrane of some of the epithelial cells was ruptured. Within these ruptured cells one or two cellular elements could be found which resembled epiplexus cells. The inclusion cell sometimes appeared to be migrating out of the epithelial cell. It is speculated that these cells represent the precursors of epiplexus cells before their release into the ventricle lumen.

Animals↗
PubMed1997

Nondiseased dentinal root surface following citric acid or tetracycline hydrochloride conditioning: a scanning electron microscopic study on the effects of ultrasonic irrigation before and after root conditioning.

The scanning electron microscope was used to evaluate the effects of ultrasonic irrigation before and after root conditioning. Six groups of five specimens each received saline irrigation; ultrasonic irrigation; saline irrigation followed by root conditioning with either citric acid or tetracycline hydrochloride; or ultrasonic irrigation followed by root conditioning with either citric acid or tetracycline hydrochloride. After immersion in citric acid or tetracycline hydrochloride solutions, root dentin was rinsed again with saline or irrigated ultrasonically. Control specimens exhibited an amorphous, irregular surface smear layer. Ultrasonic irrigation, citric acid, and tetracycline hydrochloride were effective in removing the smear layer. Use of ultrasonic irrigation before and after acid application improved the exposure of dentinal fibrils.

Acid Etching, Dental↗
PubMed1997

A study of glass-ionomer cement and its interface with enamel and dentin using a low-temperature, high-resolution scanning electron microscopic technique.

This report describes a method of immobilizing the water contained in glass-ionomer cement and dental hard tissues and stabilizing the delicate organic component of dentin. With this method, the intact interface between glass-ionomer and dental hard tissues can be observed under scanning electron microscope with few of the artifacts that are caused by the desiccation associated with conventional scanning electron microscopic studies. There was a distinct zone of interaction between the glass-ionomer cement and enamel and dentin. Under severe thermal stress, glass-ionomer cement failed cohesively, leaving an intact interface with enamel and dentin. Machine-mixed glass-ionomer cements displayed a high level of porosity. Some glass particles were separated from the matrix, and there was evidence that some are dislodged from the matrix during specimen preparation.

Dental Enamel↗
PubMed1981

The cloaca of Myxine glutinosa (Cyclostomata): a scanning electron microscopical and histochemical investigation.

The cloaca of Myxine glutinosa was examined by histochemical and scanning electron microscopical methods. No copulation organ could be found in Myxine and no detectable differences in the anatomy of the cloaca between male and female Myxine glutinosa. The anal gland which is the only gland in the cloacal region is situated between rectum and ductus coelomaticus. Like the lateral mucous glands in the epidermis it consists of large mucous gland cells, thread cells and undifferentiated cells. The cloacal epithelium neither develops a spatial separation by folds nor a ciliation is present in the caudal and dorsal part of the cloacal chamber. Therefore female and male myxinoides do not show any structures which would allow transportation of sperm into the abdominal cavity or out of it.

Animals↗
PubMed2003

Light and scanning electron microscopic evaluation of Glyde File Prep in smear layer removal.

AIM: To evaluate the effectiveness of Glyde File Prep used in conjunction with sodium hypochlorite irrigation in the removal of smear layer produced during root canal instrumentation. METHODOLOGY: Thirty-nine extracted human teeth with single root canals were used. Access cavities were prepared and the teeth divided into three groups of 13 teeth each. Each group was treated by one of the three different regimes of irrigation and conditioning during root canal instrumentation. Group A: 0.5 mL of 1% NaOCl irrigation after each file size with an additional final irrigation of 10 mL 1% NaOCl; group B: 0.5 mL of 1% NaOCl irrigation after each file size with an additional final irrigation of 10 mL 17% EDTA; group C: Glyde File Prep coated on each instrumentation file used in conjunction with 0.5 mL 1% NaOCl irrigation after each file size and an additional final irrigation of 10 mL 1% NaOCl. The teeth were then longitudinally grooved and sectioned. Root canal cleanliness was evaluated with the aid of a Nikon light microscope (x40 and x100) and scanning electron microscope (x1000 and x3000). The debris scores obtained at three canal regions were compared statistically within the same group and among different groups using repeated measurements of analysis of variance (anova) with Bonferroni adjustments and anova with posthoc Tukey HSD, respectively. RESULTS: The canals treated with EDTA and Glyde File Prep were significantly cleaner than those treated with NaOCl alone. The apical region of the root canals generally displayed more residual smear layer, but the difference was not significant. CONCLUSIONS: Used in conjunction with NaOCl irrigation, Glyde File Prep was effective in removing smear layer produced during root canal instrumentation.

Analysis of Variance↗
PubMed1975

Neuronal migration during the early development of the cerebral cortex: a scanning electron microscopic study.

Fixed cerebral vesicles of mouse foetuses were fractured and examined with the scanning electron microscope. This method provides a study of the three dimensional developmental features of the pseudostratified columnar epithelium up to the formation of the early cortex plate. Matrix cells are a cell population of homogeneous shape, however, mitotic cells are easily identified by their spherical form. The external surface of the brain is formed by the closely packed end feet of these cells covered by a basal membrane. The formation of the cortical plate is the result of a continuous cell migration in columnar arrangement towards the pia. Glioependymal cells extend along the whole brain wall and most likely provide guidance for the migrating cell cords. The formation of the so-called migratory zone is a consequence of the growth of the basal and the horizontal prolongations of emigrating cells. The significance of the cell to cell contacts for the neuronal migration processes is discussed.

Animals↗
PubMed2000

A reconstruction method of surface morphology with genetic algorithms in the scanning electron microscope.

A reconstruction method of surface morphology with genetic algorithms from a line scan in the scanning electron microscope (SEM) has been developed. This method is an application of genetic algorithms, which are search algorithms based on the mechanics of natural selection and genetics, to surface morphology in SEM. To reconstruct the microstructures of a specimen surface on a substrate, the system requires only a line scan taken by a conventional SEM. To deal with statistical fluctuations in the grey level of each pixel on the experimental line scan, the reduced chi-square distribution is used as the objective function and a scheme for minimizing the number of vertices in the reconstructed surface profile is adopted. The resolution in the Z-direction tends to be statistical and independent of the angle of the specimen surface.

Journal Article↗
PubMed1986

The value of external morphology in the identification of larval anisakid nematodes: a scanning electron microscope study.

We studied larval nematodes of four genera of the Anisakidae using a scanning electron microscope (SEM). The anterior and posterior extremities and cuticular structures of the 3rd-stage larvae (L3) of Anisakis type I, Pseudoterranova decipiens, Contracaecum type B and Hysterothylacium were examined. The 4th-stage larvae (L4) of Anisakis type I, P. decipiens, recovered after infection into laboratory rats, and the L3 and L4 of Anisakis type I larvae from human were also examined in the same way. There were generic differences in the shape and size of the lip bulges, external papillary structures, the appearance of the boring tooth, the width and depth of the grooves and ridges of the cuticle and the caudal structures of the L3. In Anisakis type I and P. decipiens L3, changes were seen in the anterior extremity, cuticle and posterior extremity after molting to the L4. Similar changes can be expected in larvae infecting man. The L4 of Anisakis type I from rat and man were similar, while the L4 of Anisakis type I and P. decipiens showed differences. These ultrastructural differences might be of value in the identification of fragments recovered during endoscopy in man.

Animals↗
PubMed1976

[Preparation of biological specimens for the scanning electron microscope (author's transl)].

Three methods usually applied in preparing biological material for the scanning electron microscope were tested by the investigation of two species of amoebae with different content of water (Amoeba proteus, Vannella simplex). Air drying resulted in both the production of cell shrinkage and cell distortion. When the specimens were dryed from media with increasing vapour-pressure, more satisfactory preservation of surface structures could be obtained. The sequence of potency was: Ethanol, chloroform, isopentane, ethyl ether, freon 11 and freon 13. Short drying periods proved to be more favourable than long ones. Critical-point drying provided much better details of cell surface morphology in both amoebae species. However, some arteficial changes were still detectable as small breaks and destruction of the mucous layer. They must be attributed to the fixation and dehydration procedure. Freeze drying turned out to be superior to both air drying and critical-point drying. Specimens prepared by this method showed no visible differences in cell surface morphology compared to living cells. As a consequence of the relatively high content of water the preparation of A. proteus was more difficult than that of V. simplex.

Amoeba↗
PubMed1988

Effects of tracheostomy on human tracheobronchial mucosa: a scanning electron microscopic study.

The protective functions missing in the upper airways of tracheostomy patients lead to functional and morphological changes in the lower respiratory tract. To obtain detailed data from the surface of the tracheobronchial mucosa, a scanning electron microscopic study was performed. Mucosal biopsies were taken from different sites of the tracheobronchial tree in 5 healthy control subjects, 5 patients with tracheostomy after laryngectomy, and 5 tracheostomy patients not affected by a history of smoking. Following scanning electron microscopic examination, the specimens were evaluated morphometrically. The percentage ciliary border and the individual mucosal surface changes depended on the biopsy site and the degree of previous damage. Individual structural alterations consisted of squamous metaplasia, giant cilia, compound cilia, and microplicae. Giant cilia represented an impressive form of differentiation in chronic bronchitis recognizable by scanning electron microscopy.

Bronchi↗
PubMed1984

[Sequential changes of vascular intimal ultrastructure in experimental cerebral vasospasm induced by oxyhemoglobin. Scanning electron microscopic study].

Organic changes of vessel wall may play an important role in the pathophysiology of vasospasm after subarachnoid hemorrhage. Sequential changes of intimal ultrastructure in experimental vasospasm induced oxyhemoglobin were investigated by scanning electron microscope. Thirty-four cats were used for this study. The basilar artery was exposed by transcervico-transclival approach. Oxyhemoglobin solution was applied under the arachnoid membrane around the artery in 16 cats at hourly intervals. Of 16 cats, 3 were sacrificed at 1 hour after the first application of the solution, 3 at 3 hours, 3 at 6 hours, 3 at 12 hours, 4 at 24 hours. Three sham-operated cats treated by artificial CSF were used as the control together with 5 untreated normal cats. All procedures were performed under aseptic condition. Perfusion fixation was done. The luminal surface and the cut surface made by freeze-fracture method were investigated by scanning electron microscope. As oxyhemoglobin solution, oxyhemoglobin-rich hemolysate was used and the concentration was 5.5 mM. By hourly application, continuous vasoconstriction of about 70% of the control diameter was obtained. In the control, the endothelial cell layer was flat. The elastic lamina had mild waving, and the luminal surface was smooth. In 1- and 3-hour groups, the elastic lamina was corrugated and the endothelial cells were protruded into the lumen in the depressed portion of corrugation. In 6- and 12-hour groups, degenerative changes of the endothelial cells, crater-formation and ballooning, were seen. Some blood-born cells adhered to the luminal surface in such cases. In 24-hour group, the changes of the endothelial cells became more remarkable.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗