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At least 19 recordsLinked to original sources
PubMed1979

In vitro studies of gallstone dissolution using the scanning electron microscope.

Scanning electron microscope studies on cholesterol gallstones, which had been subjected to, but had not been completely dissolved by, chenodeoxycholate and deoxycholate salts, have indicated the presence of an insoluble organic matrix, probably a mucopolysaccharide. Solution of a gallstone in vitro is enhanced by the addition of heparin which dissolved this matrix, thus allowing complete dissolution of cholesterol in a gallstone.

Chenodeoxycholic Acid↗
PubMed1975

A comparative study in the transmission electron microscope and scanning electron microscope of intracellular structures in sheep heart muscle cells.

The internal cellular structures of the sheep ventricular myocardium have been comparatively studied in the transmission electron microscope (TEM) and in the scanning electron microscope (SEM). For TEM studies the tissue was prepared according to standard methods. Thick sections (10 mum) of paraffin embedded material were, after they had been deparaffinized in toluene, critical point dried, coated with gold and examined in the SEM. The comparative TEM and SEM investigations revealed very good correspondence, and it is evident that the described preparation procedure for SEM has preserved the fine structures of myofibrils, mitochondria, T-Tubules and sarcoplasmic reticulum in an excellent life-like pattern. Of special interest was the three-dimensional demonstration of triads and circumferentially arranged T-tubules.

Animals↗
PubMed1979

A semithin light microscopic, transmission electron microscopic and scanning electron microscopic study of macrophages in the lateral ventricle of mice from embryonic to adult life.

A developmental study of intraventricular macrophages was carried out from 11 days post-conception up to 90 days post-natum, using semithin sections, transmission electron microscopy and scanning electron microscopy. In semithin sections and in the TEM three main morphological types (and some transitional forms) were identified and are described as circular, irregular and flattened, respectively. In the SEM three corresponding types were identified, a relatively smooth spherical type, a highly ruffled type and a fairly smooth flattened type. A fourth, multi-blebbed type, was occasionally seen in late prenatal and early postnatal mice. It seemed most likely that these cells were mitotic. The likely sequence of development is that the spherical or circular type is the most primitive, although capable of phagocytosis; and that this differentiates into the ruffled or irregular variety, which in turn differentiates into the flattened type, which is by far the most common type found after birth.

Aging↗
PubMed1978

Abnormal "hair-like" filaments in chronic maxillary sinusitis . A scanning electron microscopic investigation.

Scanning electron microscopic investigations were performed on the maxillary sinus mucosa of five healthy persons and seven patients with chronic maxillary sinusitis. The occurrence of previously undescribed hair-like filaments in one case of chronic maxillary sinusitis is presented. These abnormal filaments are much longer (about 50--60 micron) and thinner (about 0.08 micron) than normal kinocilia (about 0.2 micron thick and 5--7 micron long), thus exhibiting a hair-like appearance. As the microvilli (cytofila) in maxillary sinus mucosa have the same thickness (about 0.08 micron), these hair-like filaments could be regarded as abnormally long microvilli. The possible significance of these abnormal filaments is discussed.

Humans↗
PubMed1979

[Light microscope and scanning electron microscope findings in acute keratoconus (author's transl)].

An acute keratoconus was examined for the first time using a scanning electron microscope. The alterations in the epithelium of the cornea consisted of a reduction in microvilli and microplicae structures, disruption of the intercellular spaces with raised protrusions of epithelial cells in the region of the peak of the keratoconus or even of the complete disappearance of all regular surface structures. In the stroma distinct irregularities in the lamellae, sometimes even the formation of cavities in the region of the cornea peak, could be seen. These findings correlate well with the light microscope pictures and with the published transmission electron microscopic results.

Acute Disease↗
PubMed1977

The epithelium in healing experimental standard lesions in the gastric mucosa of the rat. A light microscopical and scanning electron microscopical study.

In a series of experiments in rats, the movement of the advancing sheet of epithelial cells streaming from a border region into the woind bed of standardized defects in the glandular mucosa of the stomach was studied using the light microscope and the scanning electron microscope (SEM). A very high synthetic activity of mucus in gastric lining cells of the border region (with a typical shift in its reaction product towards a more acidly reacting product showing metachromasia with toluidine blue) was observed histochemically, together with a loss of characteristic features of glandular cells in the border region with an increase in mitotic activity. The SEM images enabled a detailed analysis of the advancing epithelial front in its relation to the border regions. Considerable local differences were noted in the moving pattern of the migrating epithelium, possibly in relation with the nature of the base on which it has to move. The lesion of 3 mm diameter appeared to close usually after 10 days; in some instances, however, small epithelial defects were later found which could easily be traced with the SEM.

Animals↗
PubMed1977

[Light microscopic and scanning electron microscopic observations on phagocytosis of Plasmodium berghei infected erythrocytes by mouse macrophages [author's transl)].

Peritoneal macrophages from mice were cultured in Leighton tubes for 2 hours. Thereafter suspensions of washed red blood corpuscles originating from Plasmodium berghei-infected mice were offered to the cultured cells for phagocytosis. After 15 minutes of incubation 13,5% of the macrophages showed phagocytized parasites if the peritoneal cells came from malariaimmune mice. Cells from normal mice or from infected mice had lower rates (4,8/9,1%). After an incubation of 3 hours about 50% of the cells showed phagocytosis in all three groups. The system used allowed to estimate the halftimes for intracellular elimination of the parasites. The values are 27 minutes for cells from immune animals, 57 minutes for cells from normal animals, and 66 minutes for cells from infected animals. Details of the process of phatocytosis were recorded by scanning electron microscopic pictures.

Animals↗
PubMed1977

Vascularization of the pars intermedia of the hypophysis in the toad, , Bufo bufo (L.) (Amphibia, Anura). A comparative light microscopical and scanning electron microscopical study. II.

The vascularization of the pars intermedia of the hypophysis of the toad, Bufo bufo (L.) was studied by injection of a mixture of India-ink and gelatine into the circulatory system of the head via the arteria carotis communis. Further methyl-methacrylate corrosion casts of brains were made and the hypophysial region of the corrosion casts was examined with the scanning electron microscope. The results showed that the vascularization of the pars intermedia of the toad hypophysis consists of a single-layered vascular network, which is located on the ventral surface of the pars intermedia. The network is formed by capillaries, which primarily run caudally in a fan-like manner and which show only a few cross-connections. In the rostral region of the pars intermedia this network lies rather superficially, while in the caudal region it slightly penetrates the parenchyma. The vascular network originates from vessels of the neural stalk and from wide capillaries of the rostro-ventral region of the neurointermediate junction. The venous drainage of the pars intermedia is exerted by veins, which leave the caudal region and drain into the veins leaving the venous pole of the pars distalis. The flat, wide meshed vascular net on the ventral side of the pars intermedia, demonstrated in this study, fits into the concept that the pars intermedia of the anuran hypophysis is under the control of nerve fibers coming from the hypothalamus.

Animals↗
PubMed1977

Vascularization of the pars distalis of the hypophysis in the toad, Bufo bufo (L.) (Amphibia, Anura). A comparative light microscopical and scanning electron microscopical study. I.

The vascularization of the pars distalis of the hypophysis of the toad, Bufo bufo (L.), was studied by the traditional method of injecting a mixture of India-ink and gelatine into the circulatory system of the head via the arteria coratis communis. Further, methyl-methacrylate corrosion casts of the brains were made; the hypothalamo-adenohypophysial region of these corrosion casts was studied with the scanning electron microscope. The results showed that the portal vessels which arise from the median eminence do not supply distinct areas in the pars distalis as is supposed by the point-to-point-hypothesis. The portal vessels enter the ventro-median region of the pars distalis and branch off into a three-dimensional network of the secondary capillary plexus of the pars distalis. The plexus is made up mostly by four- to six-sided meshes. This angioarchitecture guarantees an optimal supply of the glandular cells of the pars distalis with nutritional factors and releasing hormones, on the one hand, and facilitates the removal of the hormones which are released by these cells, on the other hand. The venous drainage of the pars distalis is exerted mainly by two large veins, which bilaterally leave the dorso-lateral region (venous pole) of the pars distalis and by a few small veins, which drain into the wide, sinus-like vessel, which curves around the dorso-caudal region of the pars distalis and joins bilaterally the vena hypophysea transversa.

Animals↗
PubMed1977

Lesions of experimentally induced colibacillosis in neonatal gnotobiotic pigs: a scanning electron microscopic study.

Scanning electron and light microscopy were used in studies of stomach, duodenum, cranial, and caudal portions of the jejunum, ileum, cecum, and spiral colon from 18 gnotobiotic pigs. Five pigs were raised as controls and 13 were exposed at 6 days of age by oral administration of 1.6 X 10(6) colony-forming units of Escherichia coli O138:K81:NM. Infiltration of leukocytes into the mucosa of the stomach seen with the light microscope has not been previously reported. The irregular pattern of the mucosal surface of the stomach formed by the gastric pits and the mucosal extensions on the individual rugae revealed with scanning electron microscopy was different than anticipated. Sections of the ileum from control and infected pigs contained collapsed cells around the extrusion zone at the tips of the villi. These collapsed cells were more numerous in infected pigs and appeared to have sloughed from the area of the extrusion zone resulting in exposure of the lamina propria. Cecum and spinal colon were free of changes. Alterations of the mucosa of the intestinal tract of gnotobiotic pigs infected with E coli as visualized by scanning electron microscopy were considered too inconsistent to be of diagnostic significance.

Animals↗
PubMed1979

Surface configuration of mesothelial cells in effusions. A comparative light microscopic and scanning electron microscopic study.

Surface configuration of mesothelial cells identified by light microscopy (LM) has been studied by scanning electron microscopy (SEM). It has been shown that mesothelial cells may have a variable SEM appearance. The surfaces of a small proportion of mesothelial cells are covered by regular microvilli (MV) and show openings of the pinocytotic vesicles. The surfaces of the majority of these cells are covered by vesicles or blebs. An intermediate population of mesothelial cells, i.e., cells displaying side-by-side blebs and MV, has also been observed. The latter cells no longer display pinocytotic vesicles. Occasional mesothelial cells have smooth surfaces. It has been shown by LM and transmission electron microscopy that cells with blebs are viable and capable of mitotic activity. It is concluded that mesothelial cells, detached from their epithelial setting, lose microvilli and pinocytotic vesicles and acquire surface blebs. The possible relationship between mesothelial cells and macrophages based on surface features has been discussed.

Animals↗
PubMed1979

Crohn's disease: a scanning electron microscopic study.

A scanning electron microscopic study of Crohn's disease was done using surgically resected specimens. Grossly normal resection margins as well as nonulcerated portions from diseased areas were selected for study. Scanning electron microscopic findings in Crohn's disease included changes in villous size and shape, villous fusion and epithelial bridge formation, goblet cell hypertrophy and hyperplasia, and increased secretion of mucus. These changes were marked in involved areas, and many were also present in six of seven margins of resection available for study in the ileal group. The abnormalities found in grossly normal margins of resection suggest a more widespread involvement than can be appreciated by gross and light microscopic examination of the specimen. Formation of the increased coat of mucus observed may be stimulated by a number of agents and could contribute to an enhanced barrier function in areas of early involvement in Crohn's disease, thereby decreasing the uptake of toxic or antigenic macromolecules. A decrease in bacterial superinfections would also be facilitated. Later lesions, with severe villous changes and hypersecretion of mucus, may favor the uptake of toxic and antigenic macromolecules as well as aid in the establishment of bacterial superinfections.

Adolescent↗
PubMed1977

The vascularization of the neural stalk and the pars nervosa of the hypophysis in the toad, Bufo bufo (L.) (amphibia, anura). A comparative light microscopical and scanning electron microscopical study.

The angioarchitecture of the neural stalk and the encephaloposthypophysial portal system of the hypophysis of the toad, Bufo bufo (L.), was studied using three different methods. The neural stalk is mainly supplied by branches of the arteria infundibularis superficialis which form a widemeshed vascular network. Dorsally this network continues into the plexus of the pars nervosa. The vascularization of the pars nervosa is made up of the encephalo-posthypophysial portal system. This portal system consists of a hypothalamic branch (=portion), a mesencephalic and a mesencephalicbulbar branch (=portion). The hypothalamic branch was found to drain the pars ventralis of the tuber cinereum as well as more dorsal regions of the diencephalon. The mesencephalic-bulbar trunk enters the hypothalamic branch. The resulting common stem of the encephalo-posthypophysial portal vein the curves around the retroinfundibular communicating artery, crosses its ventral side and runs caudally. The secondary capillary plexus of the pars nervosa is characterized by well defined capillary plexus of the pars nervosa is characterized by well defined capillary networks which are located at the periphery of the parenchyma of the pars nervosa, thus forming a rostral, dorsal and ventro-caudal net. The central region of the parenchyma of the pars nervosa is supplied only by main branches of the encephalo-postpophysial portal vein. The venous drainage of the pars nervosa is via the vena hypophysea transversa.

Animals↗
PubMed1975

[The enamel-dentin membrane in the scanning electron microscope].

In the scanning electron microscope in detailed structure of the dentino-enamel membrane can be investigated. This membrane is mineralized. After partial demineralization it covers the bottom of prism margins and enables their firm anchoring on the surface of dentin. Here the prism bundles are anchored in dishlike formations, on the bottom of which a network of fibers is found, covered by the dentin-enamel membrane. Through artificial fissures in the membrane the above mentioned network of fibers can be seen.

Bicuspid↗