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At least 1,279 records · Page 71Linked to original sources
PubMed1991

Three-dimensional architecture of the human myosalpinx isthmus. Scanning electron microscopy after NaOH digestion and ultrasonic microdissection.

The three-dimensional architecture of the human isthmic myosalpinx is directly visualized by means of scanning electron microscopy after removal of interstitial connective tissue through NaOH maceration and ultrasound microdissection. These investigations show that the myosalpinx is composed of irregularly running bundles of smooth muscle cells, changing their orientation within the myosalpinx and displaying longitudinal, oblique and circular directions. The muscular bundles anastomose and intermingle with other bundles running at different levels in the oviduct wall, and actually give rise to a wide and complex muscular network in which no distinct layers are readily discernible. These morphological data are consistent with the physiological findings that the transport of gametes and embryo in very early stages in the isthmic portion of the oviduct tube is the result of a discontinuous pattern of forward and backward movements.

Animals↗
PubMed1993

Morphological study by scanning electron microscopy of the lingual papillae in the common European bat (Pipistrellus pipistrellus).

There are many accounts of the tongues of mammals observed with scanning electron microscopy (SEM), but apparently only one article about the tongue of the Chiroptera. In the present study the tongue surface (after removing extracellular material) of the European common bat (Pipistrellus pipstrellus) was examined. The tongue is covered with papillae and has an elevation between its medial and posterior half. There are three types of papillae: filiform, fungiform and circumvallate, and the filiform can be classified as strictly filiform, conical and crown-like. The shapes and disposition of these papillae are related to function, which is principally to retain captured food during flight. At higher magnification the surface of the filiform papillae has many pores and microridges, which may serve for the production and distribution of mucus over the papillary surface.

Animals↗
PubMed1990

Scanning electron microscopy of male genitalia of Dermatobia hominis (Diptera: cuterebridae).

The male genitalia of Dermatobia hominis L. is described morphologically by the use of scanning electron microscopy (SEM) and compared, under light microscopy, with other Cuterebridae D. hominis differes from Metacuterebra apicalis (Guérin-Méneville) because it has longer gonopods, shorter parameter, a small crest and spines on the distiphallus a bellshaped gonopore with a prominent external outline, and surstyli with a spatulate distal region.

Animals↗
PubMed1991

Scanning electron microscopy of normal and vasospastic monkey cerebrovascular smooth muscle cells.

Normal cytoarchitecture of smooth muscle cells of monkey cerebral arteries was studied using scanning electron microscopy after removal of adventitial connective tissue by hydrolysis with HCl. Cerebral arteries were also examined after contraction in vitro with prostaglandin F2 alpha (PGF2 alpha). Anterior cerebral arteries were studied after exposure for 6 days in vivo to whole blood, oxyhemoglobin, methemoglobin, bilirubin, mock cerebrospinal fluid, or supernatant fluid from an incubated mixture of autologous blood and mock cerebrospinal fluid. Normal smooth muscle cells were spindle-shaped and oriented circumferentially around the vessel. They were often grouped into bundles of 5 to 10 cells; bundles were recognizable because cells within them were joined by multiple intercellular contacts. Groups of smooth muscle cells oriented longitudinally were present outside the circular layers of cells. The adventitial surface of muscle cells was smooth apart from fine longitudinal striations in some areas. Arteries contracted with PGF2 alpha had markedly convoluted and folded cell membranes. Muscle cells of vasospastic arteries and of arteries exposed to oxyhemoglobin and supernatant fluid appeared identical to cells contracted with PGF2 alpha. The outer surface of cells of arteries exposed to bilirubin, methemoglobin, and mock cerebrospinal fluid were normal. Marked similarity between vasospastic smooth muscle cells and smooth muscle cells from arteries contracted with PGF2 alpha suggest that smooth muscle contraction occurs during "vasospasm" due to whole blood and to intrathecal injection of oxyhemoglobin.

Animals↗
PubMed1977

Surface features of Sezary cells: A scanning electron microscopy study of 5 cases.

The surface features of circulating cells from 5 patients with typical Sezary's Syndrome (SS) are described using scanning electron microscopy (SEM). Sezary cells prepared by different methods, with and without prior fixation in cell suspension, showed similar surface architectures. SS cells were mostly spherical and moderate to markedly villous in appearance, and in this respect, resembled the majority of circulating lymphocytes from patients with chronic lymphocytic leukaemia (CLL). A proportion of cells were larger and more irregular in shape while others had small extensions of cytoplasm resembling small uropods with clusters of polarised microvilli. Despite the latter findings, most SS cells cannot be distinguished from CLL cells on the basis of their surface architecture under the SEM.

Cell Membrane↗
PubMed1985

Scanning electron microscopy of normal human corneal epithelium obtained by scraping-off in vivo.

The surface of normal human corneal epithelium was examined by scanning electron microscopy (SEM). The study was carried out on specimens obtained by scraping-off in vivo, and immediately fixed. Four different types of microprojections were observed on the epithelial surface: microridges, microvilli, tufted microvilli and knobs. Detailed high magnification of surface microprojections showed that they consist of subunits. Our data suggest a correlation between surface morphology and maturity of the corneal epithelial cell. An evolutive sequence is proposed, from the youngest cell, provided with microridges, to the oldest exfoliating one, with knobs.

Cornea↗
PubMed1975

Fruiting-body formation and myxospore differentiation and germination in Mxyococcus xanthus viewed by scanning electron microscopy.

Streaming cells, fruiting bodies, and single cells undergoing myxospore differentiation and germination were examined in the FB strain of Myxococcus xanthus by scanning electron microscopy. Myxospores differentiated in fruiting bodies differed in size, in kinetics of germination, in the fate of the myxospore capsule, and in the external structure of the walls of newly emerged cells when compared with myxospores differentiated in liquid medium after glycerol induction. Vegetative cells outgrowing from glycerol-induced myxospores were regularly pleomorphic, a condition that persisted through the first cell division.

Cell Aggregation↗
PubMed1984

Scanning electron microscopy studies of erythrocytes in spinocerebellar degeneration.

Spinocerebellar degeneration is a heredofamilial disease of unknown aetiology. The shape of erythrocytes as revealed by scanning electron microscopy was studied in this disease. Echinocytes I, as defined by Bessis, were seen more frequently in spinocerebellar degeneration than in age and sex matched controls (7.2 +/- 1.5% in spinocerebellar degeneration, 3.4 +/- 1.2% in controls, p less than 0.001), Parkinson's disease, motor neuron disease, myopathy, and Huntington's chorea. Erythrocyte deformability was impaired to a greater extent in spinocerebellar degeneration than in the controls when the pH was raised from 7.2 to 8.0; Echinocytes I in spinocerebellar degeneration increased from 8.4 +/- 0.6 to 15.4 +/- 2.4%, in the control group from 2.8 +/- 1.2 to 13.3 +/- 2.1%. In spinocerebellar degeneration no significant correlation was found between the level of serum low density lipoprotein and the number of Echinocytes I. In both groups there was a significant correlation between the occurrence of Echinocytes I and age, and the difference of Echinocytes I was greater in aged subjects in spinocerebellar degeneration. The data suggest that membrane abnormality in erythrocytes exists in spinocerebellar degeneration and may be accelerated with the advance of age.

Adult↗
PubMed1995

Retinal vascular changes during aging in Wistar Kyoto rats. Application of corrosion cast and scanning electron microscopy.

Retinal vasculature changes during aging in normal Wistar Kyoto rats maintained to longevity without known diseases were studied by corrosion casts and scanning electron microscopy (SEM). Six-month-old rat retina showed regular running and arrangement of retinal blood vessels. In 18-month-old rats, a definite morphological change was moderate tortuosity of the vessels, especially at the posterior pole of the retina. In 24-month-old rats, the retinal arteries and veins were very tortuous and narrow, and their calibers were irregular. In some animals occlusion of the veins and localized constriction of the arteries and veins were evident in the vascular casts. Neither arteriovenous crossing defects nor microaneurysms were seen. Retinal capillaries showed marked changes: localized narrowing, constriction, bead-like features, caliber irregularity and occlusion. The corrosion cast method with SEM can demonstrate the details of the capillary networks in the rat retina. The findings demonstrated appear to be related to aging.

Aging↗
PubMed1978

Scanning electron microscopy of the spreading of barium sulfate suspensions on the gastric mucosa of the rat. Effect of wetting agents, bile salt and lecithine.

Scanning electron microscopy was performed on the rat stomach mucosa after application of BaSO4 and three barium-containing commercial contrast media. The degree of flocculation was assessed; flocculation could be prevented by using synthetic wetting agents and by physiologic, natural emulsifiers, sodium taurocholate and lecithine.

Animals↗
PubMed1990

The three-dimensional organization and ultrastructure of lymphatics in the rat intestinal mucosa as revealed by scanning electron microscopy after KOH-collagenase treatment.

The three-dimensional organization and ultrastructure of lymphatics in the rat intestinal mucosa were studied by scanning electron microscopy using the KOH-collagenase digestion method (to remove extracellular connective tissue matrices) and by conventional transmission electron microscopy. Each villus possessed three or more lymphatics in the deeper layer of the lamina propria. These initial lymphatics were 5-15 microns in diameter and ran parallel to each other in the longitudinal direction of the villus. These lymphatics were free from adhering periendothelial cells, but had numerous cytoplasmic folds and projections of the endothelium on their abluminal surface. At the villous base, the lymphatics emptied into several thicker (about 70-80 microns) lymphatics, which further connected together to form a flat and wide sinus (intra-villous lymphatic sinus). This sinus was relatively smooth in abluminal surface. From the bottom of each sinus, several lymphatics descended perpendicularly to drain into lymphatics in the submucosa. The villous lymphatics described above seemed to be partially accompanied by bundles of smooth muscle cells, which ran longitudinally in the villous core. The submucosal lymphatics were smooth in abluminal surface and possessed no periendothelial cells. These lymphatics ran in a transverse direction just beneath the muscularis mucosae to form a two-dimensional mesh-work by anastomosing with one another. This submucosal lymphatic network was often closely associated with the muscle cells of the muscularis mucosae, but was not accompanied by submucosal arteries.

Animals↗
PubMed2000

Hexamethyldisilazane for scanning electron microscopy of Gastrotricha.

We evaluated treatment with hexamethyldisilazane (HMDS) as an alternative to critical-point drying (CPD) for preparing microscopic Gastrotricha for scanning electron microscopy (SEM). We prepared large marine (2 mm) and small freshwater (100 microm) gastrotrichs using HMDS as the primary dehydration solvent and compared the results to earlier investigations using CPD. The results of HMDS dehydration are similar to or better than CPD for resolution of two important taxonomic features: cuticular ornamentation and patterns of ciliation. The body wall of both sculpted (Lepidodermella) and smooth (Dolichodasys) gastrotrichs retained excellent morphology as did the delicate sensory and locomotory cilia. The only unfavorable result of HMDS dehydration was an occasional coagulation of gold residue when the solvent had not fully evaporated before sputter-coating. We consider HMDS an effective alternative for preparing of gastrotrichs for SEM because it saves time and expense compared to CPD.

Animals↗
PubMed2001

The tubulovesicular system of gastric parietal cells is connected to the intracellular canaliculus, rough endoplasmic reticulum and Golgi complex. A study by high resolution scanning electron microscopy.

The three-dimensional configuration of the tubulovesicular system of resting rat gastric parietal cells was determined by ultra-hihg-resolution scanning electron microscopy (SEM). Rat gastric mucosae were fixed in 1.0% glutaraldehyde and 0.5% formaldehyde in cacodylate buffer, (334 milliosmoles/kgH2O (mOsm)). To render cytoplasmic membranes visible by SEM, fixed mucosae were frozen and fractured, and the cytoplasm of fractured parietal cells was macerated by the aldehyde-osmium-DMSO-osmium procedure. With much of the cell matrix and filaments removed, SEM revealed numerous 30-60 nm tubukes, which formed a meshwork and also small cisternae about 100 nm. Some cisternae had a small, central 10 nm fenestration. The cytoplasmic surface of the tubules was smooth surfaced but some cisternal areas had attached polyribosomes. Isolated vesicles or tubules were not found in adequately macerated parietal cells. The tubulocisternal network was also connected to the Golgi apparatus. In favorable sites connections of the tubular membranes to the canaliculi were clearly visible. Continuity between these two membrane compartments suggests the probability of rapid membrane transposition when cells are stimulated to secrete acid.

Animals↗
PubMed1990

Scanning electron microscopy of the celloidin-embedded inner ear sections.

The nerve fibers running inside the organ of Corti were studied in cats by scanning electron microscopy (SEM). The fixed temporal bones were decalcified and embedded in celloidin according to the conventional method. Thick serial sections (100-150 microns) were cut parallel to the basilar membrane. After removing the celloidin, the sections were freeze-dried in t-butyl alcohol. Though some outer hair cells had been deformed, the nerve fibers were well preserved for analysis. Some new findings were observed in the present SEM study. The tunnel spiral bundle in a kitten took an atypical course on the floor of Corti's tunnel apart from the previously reported site. In the barely-patent tunnels of Corti in kittens, nerve fibers were stuck together into thick bundles and took different courses compared to those in the mature cochleas. Filiform projections of nerve fibers were climbing around the first row of the outer hair cells in the immature cochlea. These were thought to be growing ends of efferent nerves which would later grow into nerve endings.

Animals↗
PubMed1989

Scanning electron microscopy of 'normal' urothelium in patients with infiltrating bladder carcinoma.

'Normal' dome biopsies from 20 cystectomies for infiltrating bladder carcinomas were studied with scanning electron microscopy (SEM). All cases showed alterations ranging from minimal changes to numerous pleomorphic microvilli, and were classified according to Herd and Jacobs. The SEM findings and grades were correlated with dome histology and the results were quite good. However, in our opinion, the Herd and Jacobs classification and subclassifications are poorly reproducible without morphometric analysis. Nevertheless the SEM study is useful to strengthen the diagnosis of dysplasia/carcinoma in situ in 'healthy'-looking urothelium.

Aged↗
PubMed1989

Cardiac myxomas correlative study by light, transmission, and scanning electron microscopy.

A correlative morphologic study of 17 cardiac myxomas surgically excised or observed at autopsy was performed by light (LM), transmission (TEM), and scanning electron microscopy (SEM). Tumor cells occurred singly (frequently in lacunae), in cords, as vascular-like aggregates, and in complex interdigitating clusters. By TEM, myxoma cells were predominantly undifferentiated mesenchymal cells. The surface topography by SEM revealed numerous clefts and crevices and a continuous cellular lining which, by TEM, appeared to be derived from underlying myxoma cells. The myxoid stroma by SEM was interspersed by numerous reticular fibers that appeared as a sponge-like supportive framework. Complex patterns of interdigitating myxoma cells corresponded well with similar patterns by LM and TEM, demonstrating the advantage of SEM in correlative morphologic studies.

Adolescent↗
PubMed1986

Scanning electron microscopy of Bunostomum phlebotomum (Railliet, 1900).

Live specimens of Bunostomum phlebotomum were collected from the small intestine of a calf and processed for scanning electron microscopy using standard methods. This paper describes the surface morphology of adult worms. All these hookworms showed a dorsally bent anterior end with its buccal capsule, which opens antero-dorsally with a pair of chitinous cutting plates on the ventral margin. Prominent cervical papillae and a well developed male bursa with a dorsal and 2 lateral lobes, were observed. The female tail is slender and pointed with the anal opening close to the tip. Further studies are necessary to demonstrate morphological differences from other hookworms and to obtain more detail of the male bursa and female tail.

Ancylostomatoidea↗