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At least 289 records · Page 16Linked to original sources
PubMed1976

A scanning electron microscope study of mouse peritoneal mesothelium.

As seen in the scanning electron microscope, peritoneal mesothelial cells of the mouse diaphragm, anterior abdominal wall and intestinal serosa carry numerous microvilli. These microvilli are absent over certain areas of the cell surface and are sometimes, interlocked in meshwork patterns or coronal formation. The apical cell membranes of the mesothelium at the base of the microvilli, are invaginated by many plasmalemmal vesicles and vacuoles and carry a number of protruding spherical structures. Deep circular craters, giving the impression of stomata, are also visible.

Abdomen↗
PubMed1978

Tinea versicolor: a scanning electron microscopic view.

Tinea versicolor (TV) infections were studied in the scanning electron microscope utilizing several different sampling and preparatory techniques. Scalpel scrapings provided information only on the morphology of individual spores and hyphae, while biopsies and cyanoacrylate adhesive slides demonstrated the topography of the disease as well as providing information on how the infection spreads and recurs. Critical point drying was necessart to maintain the fine ultrastructure previously described. The deep follicular location of the spores seen in this study probably explains the tendency for TV to recur. The follicular packing was specific, since the eccrine pores seem to be exempt from the infection.

Humans↗
PubMed2003

A practical method for the remote control of the scanning electron microscope.

We have developed a remote control system for the scanning electron microscope (SEM). It is called Web-SEM and can be accessed by anyone through the Web browser. It is not necessary to install special software to control the SEM. Because the operating performance changes with the amount of traffic on the Internet, we have connected the Web-SEM to a LAN/Internet in order to overcome this. We have checked the performance of the remote control operation and we were able to perform focus adjustment, stage movement, etc. over the Internet by improving the method of operation and image transfer.

Data Display↗
PubMed1998

A scanning electron microscopic study of the rete testis of the guinea pig.

Scanning electron microscopic (SEM) observations of the structure of the rete testis (RT) of guinea pigs preceded by and complemented with stereomicroscopy and light-microscopic studies showed that the RT of this species is predominantly cavitary. An axial and labyrinth-like morphological pattern was also observed in the RT complex, with partially interconnected chambers and epithelium-lined channels accompanying a connective axis observed in the middle portion of the cranial end of the testis. Characteristics of the chordaeretis and bullaeretis were also visualized in the guinea pig RT and the results are discussed in terms of the morphological patterns observed in the RT of other mammals and of man.

Animals↗
PubMed1983

Scanning electron microscopic study of Dacron degradation by ocular tissue extracts.

A scanning electron microscopic study showed that the surface of Dacron thread became significantly roughened after treatment with bovine iris-ciliary body extracts. The Dacron-degrading factor in the extract was nondialysable, heat-labile, and active at an acidic pH, suggesting that lysosomal enzymes may be a factor in this phenomenon. Bovine extracts from the iris, ciliary body, and sensory retina degraded the surface of Dacron most substantially, while the Dacron surface was moderately digested by extracts from the cornea and retinal pigment epithelium. Lenticular and choroidal extracts did not affect the Dacron surface. Possibly the factor that degrades Dacron may be different from that which affects nylon, and the Dacron suture may not be preferable for corneal surgery.

Animals↗
PubMedDate not supplied

The role of induced contrast in images obtained using the environmental scanning electron microscope.

Generation of contrast in images obtained using the environmental scanning electron microscope (ESEM) is explained by interpretation of images acquired using the gaseous secondary electron detector (GSED), ion current, and the Everhart-Thornley detector. We present a previously unreported contrast component in GSED and ion current images attributed to signal induction by changes in the concentration of positive ions in the ESEM chamber during image acquisition. Changes in positive ion concentration are caused by changes in electron emission from the sample during image acquisition and by a discrepancy between the drift velocities of negative and positive charge carriers in the imaging gas. The proposed signal generation mechanism is used to explain contrast reversal in images produced using the GSED and ion current signals and accounts for discrepancies in contrast observed, under some conditions, in these types of images. Combined with existing models of signal generation in the ESEM, the proposed model provides a basis for correct interpretation of ESEM images.

Aluminum Oxide↗
PubMed1998

Low-voltage backscattered electron imaging of non-coated biological samples in a low-vacuum environment using a variable-pressure scanning electron microscope with a YAG-detector.

A variable-pressure scanning electron microscope (VP-SEM) equipped with a high-sensitive backscattered electron (BSE) detector of the YAG type was applied to studies of biological tissue samples. The rat kidney and trachea were fixed, dehydrated in ethanol, critical point-dried and examined in the VP-SEM under a specimen chamber pressure of 1 to 150 Pa. The high-resolution surface images of the non-coated specimens were obtained in a low-vacuum (1-20 Pa) environment at an accelerating voltage of 5 kV, while the images at 10-20 kV contained information beneath the surface of the specimens. The observation in the VP-SEM equipped with YAG detector in a low-vacuum (1-20 Pa) environment at low (3-5 kV) accelerating voltages is useful for the three-dimensional analysis of the surface morphology of biological non-coated samples.

Animals↗
PubMed1982

Myofiber branching in idiopathic cardiomyopathy under the scanning electron microscope.

Myofiber changes in idiopathic cardiomyopathy were examined by the scanning electron microscope in order to elucidate the three-dimensional architecture. Muscle specimens were sampled from the ventricular walls of 13 autopsy cases (7 with the congestive type, 3 with the hypertrophic type and 3 controls), and observed according to the Evan's method. In addition, the same samples were investigated histopathologically using the tribasic staining originated by Kurotaki, and the muscle cell diameters were analyzed with a pendigitizer computer system. In congestive cardiomyopathy, the hypertrophic myofibers branched more frequently and varied more in thickness than in the controls. The complex myofiber architecture seemed to be the result of the compensation for muscle weakness. On the other hand, hypertrophic cardiomyopathy revealed three-dimensional myofiber disarray, which was fundamentally constituted from a ring formation of the myofiber branches, but only at the ventricular septal wall. The structure appeared only to promote muscle stiffness.

Adult↗
PubMedDate not supplied

Transmission and scanning electron microscopic studies of cells in effusions.

The transmission (TEM) and scanning electron microscopic (SEM) features of cancer cells and benign cells from human effusions were described. Both in the TEM and the SEM the following cell types were indentified; mesothelial cells, histiocytes, lumphocytes, eosinophilic leukocytes, neutrophilic leukocytes, plasma cells, erthrocytes and cancer cells. The ultrastructure of malignant cells originating from cancers most commonly metastisizing to the serous body cavities was described in detail. Both the TEM and the SEM clearly demonstrated fundamental differences between the surfaces of the cancer cells and benign cells in body cavity fluids: cancer cells were covered by numerous microvilli, while non-neoplastic cells were not. The approach described in this paper can be used for purposes of cytologic diagnosis in difficult preselected cases and may also have some important theoretical implications.

Adenocarcinoma↗
PubMed2004

A study of recrystallization in single-phase aluminium using in-situ annealing in the scanning electron microscope.

In-situ annealing experiments were performed in the scanning electron microscope on a single-phase Al-0.13Mg alloy cold rolled to different strain levels. Once the validity of the technique had been verified by comparison of the recrystallization kinetics and final grain size with bulk annealed samples, the method was used in combination with electron back-scattered diffraction (EBSD) to study the potential mechanisms for recrystallization in this alloy. During annealing of material rolled to moderate strains (epsilont < 0.7), the primary mechanism was strain-induced boundary migration (SIBM). In material rolled to higher true strains (epsilont > 1.4), recrystallization occurred extensively along pre-existing cube bands and EBSD measurements showed that the mean size of cells within the cube bands was larger than for all other orientations measured, suggesting a size advantage was responsible for the strengthening of cube texture during recrystallization. SIBM was shown to occur concurrently with the nucleation along cube bands but this contributed a lower proportion of nucleation sites during recrystallization.

Alloys↗
PubMed1982

A scanning electron microscopic study of nylon degradation by ocular tissue extracts.

A scanning electron microscopic study showed that the surface of the nylon used for corneoscleral wound closure was smooth, while the nylon suture thread used to fix the intraocular lens against the iris showed cracks and roughness on its surface. The surface of the nylon thread was also roughened after treatment with bovine iris-ciliary body extracts. The nylon-degrading factor in the extract was nondialyzable, heat-labile, active at acidic pH, and inhibited in part by leupeptin, suggesting that lysosomal enzymes may be a factor in this phenomenon. Of the bovine ocular tissues, ciliary body extract degraded the surface of the nylon thread most significantly. The nylon surface was moderately digested by the retinal pigment epithelial extract, and slightly eroded by the extracts from the iris, sensory retina, and choroid. Corneal and lenticular extracts did not affect the nylon surface. Nylon suture thread may be hydrolyzed by lysosomal enzymes and should be considered a late-degrading suture.

Animals↗
PubMed1987

Three-dimensional organization of the connective tissue fibers of the human pancreas: a scanning electron microscopic study of NaOH treated-tissues.

A method for scanning electron microscope (SEM) study of reticular fibers in their original shapes and locations is described. This technique was employed to demonstrate the three-dimensional organization of the reticular fibers of the human pancreas. The cellular elements were effectively removed by treatment of the tissue pieces with a 10% aqueous solution of NaOH for 3-4 days at room temperature. Thin layers of the reticular fibers surrounding the acini and ducts formed a three-dimensional interstitial compartment. The reticular fiber sheaths for the blood vessels coursed through the compartment. In the lobule, there were scattered round or oval capsules for the islets of Langerhans. The capsule also consisted of reticular fibers. Within the capsule, reticular fiber sheaths for accommodating islet capillaries, representing the pericapillary spaces, formed a three-dimensionally anastomosing network. The channels for the capillaries ensheathed by the reticular fibers in the islet were continuous with those in the surrounding exocrine pancreas; thus, the insulo-acinar portal system was confirmed to exist in the human pancreas. This study also maintains that the present method is useful for examining the microvascular organization of the islet.

Aged↗
PubMed1990

[Scanning electron microscopic observations on larvae and young adults of Angiostrongylus cantonensis].

Scanning electron microscopic observations on the structure of the body surface of various larval stages and young adults of Angiostrongylus cantonensis were made. The mouth opening of the first and second stage larvae closes in "Y" form until well developed young adult stage. There are two rows of 6 sensory papillae each around the mouth. With development of the worm, the papillae of the outer row gradually degenerated and could hardly be seen in adult worms. A pair of amphidial pores was present on the external side of lateral papillae of the inner row, being conspicuous in the fourth-stage larvae. There was one excretory pore on the ventral side of the anterior end. The copulatory bursa of the male worms began to develop in the third stage larvae and became well developed in the 25-day young adults. The processes of the development of copulatory bursa were described. The gonopore could be seen in the female worm as early as in the first-stage larvae but the anal pore appeared only in the fourth-stage larvae, both of them did not develop completely until the young adult stage of 11 day old (Figs. 1-18).

Angiostrongylus↗
PubMed1989

Scanning electron microscopic observations on the endothelial healing mechanism of vessels.

Systematic scanning electron microscopic observations of the healing mechanism in the endothelium of rat carotid arteries were carried out at the site of anastomosis. The site of needle holes and stitches are the main locations for thrombocyte adhesion and aggregation in normal vascular anastomosis. The repair process in endothelial injury can be divided into three stages. A thrombocyte-adhesion and filling stage is apparent at 1 hr postoperatively; this is also the period when thrombus is most likely to occur. A fibrin-covering stage is apparent at 2 hr after operation and reaches its peak in 24 hr. The formation of fibrin provides a framework for endothelial growth. In this period, there is still the possibility of thrombus formation. At 48 hr postoperatively, endothelial growth can be seen at the site of some needle holes. At 72 hr after operation, 47 percent of needle holes have endothelial growth, and the possibility of thrombus formation at the anastomotic site declines. The data suggest that eversion of the intima in vascular anastomosis and minimization of endothelial injury by considering the size of the needle hole, the duration of ischemia time, and perfection of surgical technique, are keys to the prevention of thrombus formation at the anastomotic site.

Anastomosis, Surgical↗
PubMedDate not supplied

A high-resolution add-on in-lens attachment for scanning electron microscopes.

A compact add-on objective lens for the scanning electron microscope (SEM) has been designed and tested. The lens is < 35 mm high and can be fitted on to the specimen stage as an easy-to-use attachment. Initial results show that it typically improves the spatial resolution of the SEM by a factor of three. The add-on unit is based upon a permanent magnet immersion lens design. Apart from the extra attachment to the specimen stage, the SEM with the add-on lens functions in the normal way. The in-lens unit can comfortably accommodate specimen heights up to 10 mm. The new add-on lens unit opens up the possibility of operating existing SEMs in the high-resolution in-lens mode. By using a deflector at the top of the add-on lens unit, it can also operate as a quantitative multichannel voltage contrast spectrometer, capable of recording the energy spectrum of the emitted secondary electrons. Initial experiments confirm that a significant amount of voltage contrast can be obtained.

Journal Article↗
PubMed1988

Light and scanning electron microscopic observations of the canalicular system in human cellular cementum.

A scanning electron microscopic cast technique was used to determine the nature of the canalicular system in human cellular cementum. Prior light microscopic observations suggested the presence of two distinct types of lacunae: bone-like and a large irregular type generally confined to the interradicular region. Only the bone-like lacunae were visualized in the SEM cast preparations. The canalicular system associated with the bone-like lacunae was usually continuous from the surface of the dentin to the surface of the cementum in newly-erupted teeth. Casts having a sponge-like configuration were observed near the cementodentinal junction in some of the specimens from the interradicular region. The presence of these casts could not be predicted from prior light microscopic observations and it was concluded that they may represent infiltration of hypomineralized matrix rather than lacunae.

Dental Cementum↗
PubMed2006

[Scanning electron microscope of for endophthalmitis case].

PURPOSE: The purpose of this study was to demonstrate the usefulness of the scanning electron microscope in examining the posterior capsule and an intraocular lens (IOL) in an endophthalmitis patient. METHODS: The patient was a 77-year-old man with diabetes mellitus undergoing radiotherapy for prostatic carcinoma, and having a history of esophageal cancer. Phacoemulsification, aspiration and IOL insertion by keratotomy were carried out. The operation was performed without complications. The IOL was a one-piece acrylic type. However, after 24 hours, we diagnosed acute bacterial endophthalmitis, because the patient showed visual loss, high intraocular pressure, fibrin formation, and an increase of cells in the anterior chamber. Vitrectomy to remove the IOL and posterior capsule was carried out on the same day. The removed samples were observed by scanning electron microscope. RESULTS: Enterococcus faecalis was detected in the vitreous and aqueous humor. The bacteria adhered to the optic and haptic surfaces and showed biofilm formation. The traces of the end mill cutting line were recognized beside the haptics. However, the posterior capsule showed no bacterial adhesion but had an unusual shape. CONCLUSIONS: We observed the biofilm formation in an IOL removed from an acute bacterial endophthalmitis case. An IOL may be an important canse of bacterial proliferation and adhesion.

Aged↗