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PubMed1978

Scanning electron microscope study on flat type membrane oxygenator after prolonged extracorporeal circulation.

Despite adequate anticoagulation, thrombi may develop onto any foreign surface subjected to circulating blood. Although the efficiency of membrane oxygenators can decrease, distal embolization can be more critical and dangerous. Scanning electron microscope observations carried out on the Travenol Modulung oxygenator used both on dogs and on patients for prolonged partial cardiopulmonary by-pass pointed out the following observations. Caution must be observed when translating the results from dogs to human beings. Heparin management can be delicate and critical. The problem of blood transfusion can be extremely important and must be extensively investigated.

Adult↗

PubMedDate not supplied

Scanning electron microscopic demonstration of goblet cell discharge and mucous layer on nasal ciliated respiratory epithelium.

Respiratory cilia is covered by a layer of mucus. The manner in which the mucus makes its way to the cilia tips and distributes itself on the tips is not known. Scanning electron microscopic examination of nasal mucosa demonstrated cone-like goblet cell discharge as well as a thin layer of mucus enmeshed in the cilia tips. Further demonstration of mucus may demonstrate the differences in these two components.

Cilia↗

PubMed1982

[Micro-constructive studies of human digital flexor tendon and tendon sheath--observation by scanning electron microscope and light microscope (author's transl)].

This report concerns a micro-construction of the human digital flexor tendon and tendon sheath. Using fresh human tendons and tendon sheaths, the specimens were prepared as continuous as possible, and observed under a scanning electron microscope. The results obtained from these observations were compared with the histological and histochemical findings and some interesting conclusions were obtained. The tendon and tendon sheath are organized to transmit the muscle contraction most effectively to the finger as a reasonable finger motion. The tendon consists of the bundles of dense collagen fibers, the endotenon which divides each tendon bundles, the epitenon which surrounds all the tendon bundles as a whole and the visceral synovial layer which bundles the top of the tendon. The fiber of the epitenon originates from the paratenon at the proximal reflexion of the synovial layer, and remain around the tendon bundle in the tendon sheath cavity. The epitenon thickens itself at the dorsal side of the tendon, and the longitudinal dorsal tendon vessels are included in the thickened epitenon. Both the epitenon and the endotenon consist of loose connective fibers and these fibers are in continuation from one to the other. The endotenon divides a tendon into bundles and includes the intertendinous longitudinal vessels inside it. It also relieves the strain of tendon aroused in the process of finger motion. The synovial tendon sheath cavity is considered as a bursa formed in the paratenon, and the volar sides of the parietal layer of the synovial tendon sheath act chiefly as the pulley in co-operation with the ligamentous tendon sheath. The dorsal sides of the parietal layer, especially in the area near the volar plate, the tendon anchoring area, the reflexion area of the synovial layer and the origin of the tendon vinculum, form the areolar-type of synovial layer, and are concerned in production of the synovial fluid. Some of the synovial cells in the synovial layer are stained metachromatically with the histochemical stains, and they are considered to produce the synovial fluid mainly composing of the hyaluronic acid. The synovial fluid gives a biological activity and a biomechanical lubrication to the tendon function. The paratenon, the mesotenon and the vinculum are all paratendinous tissues, which function as the tendon anchor and provide the paths for vessels to the tendon. These structures have been modified into the individual forms through the adaptation to the needs of function and to the environments surrounding them. The paratenon locates in the area where the tendon runs straight in the shortest excursion, and the mesotenon in the area of the curved long excursion as in the case for carpal tunnel or tarsal tunnel where is covered by the tendon sheath or the retinaculum. The vinculum exists in a highly differentiated narrow space such as the no-man's land of finger, and has remained as the minimum unit to maintain the blood supply to the tendon.

Adult↗

PubMed1979

Scanning electron microscope study of Saccharomyces cerevisiae spheroplast formation.

A suspension of Saccharomyces cerevisiae NCY366 in buffered 1.2 M sorbitol containing Zymolyase-5000 (a beta-glucanase-containing preparation/showed maximum osmotic sensitivity after 30 min of incubation at 30 degrees C. A scanning electron microscope study of spheroplast formation, using a very high resolution (4-nm) machine, revealed several new morphological features. The surface of the plug in bud scars on intact cells appeared warty. The wall, which assumed a beady appearance as digestion proceded, ultimately sloughed off to reveal the furrowed surface of the plasma membrane. Bud scars were resistant to digestion and. as incubation proceeded, they became surrounded by an outer annulus, which may be the seconary septum. Wall material was completely removed from the majority of cells only after 60 min of digestion. The surface of spheroplasts was studded with particles, about 25 to 30 nm in diameter. Many spheroplasts had a single large indentation, which may be in that part of the plasma membrane originally underlying the birth scar.

Cell Membrane↗

PubMed1990

Scanning electron microscopic evidence for neural differentiation in Ewing's sarcoma cell lines.

A number of recent studies have suggested a relationship between Ewing's sarcoma (ES) and other small round cell tumours of childhood such as peripheral neuroepithelioma (PN). We report scanning electron microscopic studies on the character of induced neural differentiation in ES, neuroblastoma, PN, osteosarcoma and colon carcinoma. We found evidence of neural differentiation in both neural lines and in one of two Ewing's lines before treatment. After differentiation, both Ewing's and neural lines developed neuritic processes with varicosities and little arborization, except for the initially undifferentiated Ewing's line (A4573) which displayed extensive lateral sprouting from neuritic processes after differentiation. Neither treated nor untreated osteosarcoma or colon carcinoma displayed any evidence of neural differentiation. Further, neuroblastoma cells are easily distinguished from ES and PN by virtue of their single, unbranched neurites and lack of lateral sprouting or filopodia. These results provide further evidence for the neural character and close relationship between ES and PN.

Adenocarcinoma↗

PubMed1998

[Observation on trachea inner walls of six species of Sect. Stenophora by scanning electronic microscope].

OBJECTIVE: To probe and identify the ultramicro characteristics of trachea inner walls(TIW) of six species of Sect. Stenophora, i.e., Rhizoma Dioscoreae Spongiosae, Rhizoma Dioscoreae Hypoglaucae, Rhizoma Dioscoreae Futschauensis, Rhizoma Dioscoreae Gracillimae, Rhizoma Dioscoreae Tokoro and Rhizoma Dioscoreae Zingiberensis, by scanning electron microscope (SEM). METHOD: The vertical microscopical sections are stuck on the platform of species and metal plated. TIW were observed and photographed by SEM. RESULT: The ultramicro characteristics of TIW, i.e., the smoothnesss of TIW, the existence of separation bands, the density, arrangement types, shapes and sizes of pits, etc., can be seen clearly under SEM. Further, there exist differences in the ultramicro characteristics of each species. CONCLUSION: The above six species of crude drugs can be identified according to their ultramicro characteristics of TIW. SEM can be used to study the ultramicro characteristics of crude drug rhizomas thus creating a new area for identifying crude drugs.

Magnoliopsida↗

PubMed1982

Stereociliary pathology and noise-induced threshold shift: a scanning electron microscopic study.

Cats were exposed unilaterally to narrow-band noise at an intensity of 118-120 dB SPL for two hours. After long survival times thresholds of single auditory units were measured and the organ of Corti examined with a scanning electron microscope (SEM). The purpose of the study was to correlate pathologies of the hair cell stereocilia seen with the SEM with permanent hearing loss measured by elevated thresholds of single auditory nerve units. Pathological changes in inner hair cell (IHC) stereocilia were more severe and more numerous near the lesion focus diminishing progressively with increasing distance from it. Increasingly elevated thresholds correlated with increased damage to stereocilia of IHCs. Thresholds of nerve fibers innervating IHCs with missing or fused stereocilia were greatly elevated. Thresholds of fibers to IHCs with disarrayed stereocilia also seemed to be elevated but to a lesser degree.

Acoustic Stimulation↗

PubMed1985

[Scanning electron microscopic observations on gastric cancer].

On the basis of transmission electron microscopy of the gastric cancer, 10 cases with various types of the same tumor were further observed by Hitachii S-450 scanning electron microscope (SEM). The mucosa of the gastric cancer, para-cancer area and the perigastric lymph nodes were taken and fixed with penta-aldehyde and osmic acid, then processed into scanning specimens. By SEM, the para-cancer mucosa was quite similar to the "normal" gastric mucosa. Its free surface looked like strawberry. The gastric papule and fovea could be seen and the border of the cells was distinct. There was an uneven spacial structure similar to mountains and valleys at the border between the mucosa of the cancer and the non-cancer area. The mucosa of gastric adenocarcinoma showed wornout cotton-like erosion and destruction losing the normal tissue structures. The mucous epithelium was arranged disorderly adhered with marked dyskaryotic cancer cells. In the 2 cases of poorly differentiated adenocarcinoma and 1 undifferentiated carcinoma, metastatic cancer cells were found in the marginal sinuses of the perigastric lymph nodes. The scanogram of SEM showed a cluster of metastatic cancer cells neared and were adhering to the target organ. Some of the cells were observed stretching out their filament pseudopodia and invading the target organ. It implies a subsequent distant metastasis. Further study on the stereostructural changes of the surface membrane of cancer cells would help to explain the pathogenesis and development of gastric cancer.

Adenocarcinoma↗

PubMed1987

Fine structural changes in the articular cartilage of the rat's knee following short-term immobilisation in various positions: a scanning electron microscopical study.

The knee joints of 36 rats were immobilised in a padded plaster cast (18 in the flexed and 18 in the extended position) for 1, 2 and 3 weeks. The femoral articular cartilage was then examined under the scanning electron microscope. After 1 week's immobilisation in the flexed position, the surface layer of the cartilage showed disruption and the superficial chondrocytes were necrotic. The sites of the necrotic chondrocytes were seen as pits on the cartilage surface. In the animals whose knees were immobilised in the extended position, the changes were not so great in severity or extent. After 2 weeks, more advanced changes could be detected in both groups, but they were more severe in the flexed group. After 3 weeks the changes in articular cartilage were diffuse in the flexed, but focal in the extended group. Diffuse necrosis of chondrocytes, with pit formation on the surface and disruption and disintegration of the collagen fibres, was seen to some extent in all the animals. In the flexed group the changes extended to the whole weightbearing surface of the articular cartilage of the femur, except the intercondylar sulcus. In the extended group, a superficial fibre network was found without the formation of closely packed collagen fibre bundles, and the changes in the chondrocytes were seen only in localised zones. The authors suggest that during immobilisation, especially in the flexed position, articular hypoxia occurs due to a decreased amount of synovial fluid, the increased compression of the cartilage surfaces and the increased intra-articular pressure. This causes degeneration and necrosis of the superficial chondrocytes and the superficial cartilage layer.

Animals↗

PubMed2000

Morphological characteristics of neuromuscular junctions of the opossum (Didelphis albiventris) extraocular muscles: a scanning-electron-microscopic study.

Three types of neuromuscular junctions were described in the extraocular muscles of the opossum. The present study demonstrates the three-dimensional characteristics of these neuromuscular junctions after HCl connective tissue digestion. Adult opossum of both sexes were used and the neuromuscular junctions of the extraocular muscles were examined after removal of the intramuscular connective tissue and basal layer. This material was examined with a scanning electron microscope. Two types of 'en plaque' neuromuscular junction were described: the continuous type revealed elongated and branched primary synaptic grooves separated from each other by sarcolemma protuberances with different sizes, and the discontinuous or punctiform type which presents very shallow and discontinuous grooves when compared with the former. The multiple neuromuscular junctions were observed as two or three junctions associated with the same muscular fiber. The multiple junctions were present in thin fibers (around 11 microm caliber); the en plaque junctions were associated with large diameter fibers (around 21 microm). This study confirms and reveals the detailed morphological characteristics of the three neuromuscular junction types previously described by transmission electron microscope in the extraocular muscles of opossum.

Animals↗

PubMed1988

Scanning electron microscopic observations on vascular casts of ciliary processes in normal and topical epinephrine-treated rats.

Existence of neurohumoral control of the ciliary process blood flow was investigated in normal adult Wistar albino rats, utilizing the vascular casting method with a scanning electron microscope, comparing the ciliary process vessels in epinephrine-treated eyes to those in control eyes. The ciliary process microvasculature consisted of marginal capillaries, intraprocess capillaries and collecting veins. The supplying arterioles of the ciliary processes were derived from the iridociliary arterial circle. The arterioles were constricted or annularly impressed just before connecting with the marginal capillaries in the controls. The epinephrine instillation resulted in significant constriction of all the ciliary process vessels. Especially the ciliary process arterioles were narrowed in their full length in contrast to the focal constrictions in the controls. The diameter of the constricted arterioles in the epinephrine-treated eyes was the same as the focal constrictions in the controls. These results suggested that sphincter muscles existed in the wall of the ciliary process arterioles of the rat and that neurohumoral blood flow control was related to the constriction of the ciliary process arterioles resulting from the epinephrine administration.

Administration, Topical↗

PubMed1982

Development of a latex-conjugated immunocytological marker for scanning electron microscopic analysis of quail-chick chimeras.

Quail-chick chimeras are created by transplanting pieces of quail tissue to chick. We have used antibodies combined with a cell surface marking technique [modified after Molday et al.('75)], to facilitate scanning electron microscopic (SEM) identification of quail cells in such chimeras. First, antibodies to quail RBCs were raised in rabbits by intravenous injection. Rabbit anti-quail RBC serum was precipitated by ammonium sulfate, purified by DEAE chromatography, and cross-absorbed with chicken RBCs. Second, sheep anti-rabbit IgG was purchased commercially and further purified by affinity chromatography. Third, 900-A-diameter latex beads were synthesized by aqueous emulsion copolymerization of methacrylates. Spheres were bound with diaminoheptane to create an extension arm which was further derivatized in a two-step glutaraldehyde procedure. Purified sheep IgG was bound to the aldehyde-activated spheres, with uncoupled sheep IgG removed by sucrose density centrifugation. To test the marker, rabbit anti-quail IgG was added to 1% diluted quail RBCs. After washing, sheep anti-rabbit IgG bound spheres were introduced. Washed cells were fixed in one-half strength Karnovsky's and processed for SEM. Quail RBCs were uniformly decorated with beads, containing 2,000 beads per cell. Similarly treated chick RBCs show no binding to beads. Likewise, quail RBCs not pre-treated with the rabbit IgG do not bind beads. Prefixed quail RBCs still bind latex-conjugated beads, although at somewhat reduced levels. When mixtures of quail and chick RBCs were processed for identification: (1) sphere labeling was an "all or none" phenomenon; (2) the proportion of bead-decorated cells observable in the SEM was the same as the proportion of quail RBCs provided in the initial mix; and (3) morphologically distinguishable embryonic chick RBCs did not label whereas under the same conditions, quail RBCs do. We further demonstrate that rabbit antibodies prepared by injection of stage 4 quail primitive streaks can be used to specifically label quail epiblast and mesoblast cells, providing markers for at least two germ layers. It is now possible to combine grafting techniques of known success, with SEM analysis of the chimera.

Animals↗

PubMed1984

Effect of different aspirin doses on arterial thrombosis after canine carotid endarterectomy: a scanning electron microscope and indium-111-labeled platelet study.

Although it is widely accepted that aspirin inhibits platelet aggregation in arterial thrombosis, the appropriate dosage of aspirin remains quite controversial. The purpose of this study was to determine the effect of different doses of aspirin (0.5 mg/kg vs. 10 mg/kg) on mural thrombus formation after carotid endarterectomy. Eighteen hours after oral aspirin administration, 20 endarterectomies were performed on mongrel dogs with the use of the operating microscope. Blood flow was then restored for 3 hours and the vessels were prepared for investigation with the scanning electron microscope. Ten endarterectomies were also performed on unmedicated dogs as controls. Five minutes before vessel unclamping, autologous indium-111-labeled platelets were administered intravenously, and the endarterectomized portions of the vessels were studied with a gamma counter system after harvesting. Group 1, the control group, revealed extensive mural thrombus consisting of platelet aggregates, fibrin, red blood cells, and white blood cells. Six of the 10 vessels in Group 2, premedicated with 0.5 mg of aspirin per kg, demonstrated varying amounts of mural thrombus. Group 3 (10 vessels), premedicated with 10 mg of aspirin per kg, revealed a platelet monolayer completely covering the exposed vessel wall media, with scattered white blood cells and infrequent fine fibrin strands overlying the platelet surface. The mean (+/- SD) radioactivity per group expressed as counts/minute/mm2 was: Group 1--2055.3 +/- 1905.5, log = 7.253 +/- 0.926; Group 2--1235.6 +/- 1234.3, log = 6.785 +/- 0.817; Group 3--526 +/- 433.06, log = 5.989 +/- 0.774.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1983

[A scanning electron microscope study of the fine angioarchitecture of the uterine cervix - the process of mosaic formation and analysis of mosaic patterns].

UNLABELLED: This study was designed to analyze the process of mosaic formation by a newly established cast formation technique utilizing the scanning electron microscope. RESULTS: 1) The angioarchitecture of the mosaic pattern in squamous metaplasia shows only a loop in the minute vessel. 2) The angioarchitecture of the mosaic pattern in neoplastic lesions shows various types of basket-like structures protruding into the epithelial layer from the subepithelial capillary network. 3) The basket formation begins in low degree dysplasia when the interconnection of the hairpin-like vessels protruding into the epithelial layer from the capillary network takes place. 4) The basket is almost completely formed in high degree dysplasia and become much firmer in carcinoma in situ. 5) With advancement of the neoplastic change the basket becomes bigger and deeper, especially at the rim of basket where it becomes much thicker due to the proliferation, conglutination and enlargement of superficial vessels. 6) The destructive changes in the basket appear in early invasive carcinoma and is observed at first on the bottom and rim. This study has elucidated the fine angioarchitecture of various types of mosaic patterns and made it possible to estimate the histological change by colposcopy.

Carcinoma, Squamous Cell↗

PubMed1980

Scanning electron microscopic studies on blood vessels in cancer of the larynx.

The injection replication method was used in a study of the vascular system in cancer of the larynx. Following maceration, clean microcorrosion casts of the blood vessels of larynx cancer were examined in a scanning electron microscope (SEM). The effective filling of the whole vasculature, including its finest capillaries, makes it possible to obtain really three-dimensional pictures of the tumor blood vessels in the SEM. These SEM pictures allow a more detailed and profound analysis of the behavior and arrangement of blood vessels in three basic, angioarchitectonically differentiated zones of the tumor.

Blood Vessels↗

PubMed1980

A scanning electron microscope study of myoepithelial cells in exocrine glands.

By removing connective tissue components with enzymatic digestion followed by HCl-hydrolysis, myoepithelial cells (MECs) of the terminal portion in a variety of exocrine glands of the rat were examined with the scanning electron microscope. The profile of MECs varied considerably from gland to gland; MECs in the lactating mammary gland have a few long cytoplasmic processes in close contact with those of adjacent cells forming a continuous network around the terminal portion. Those of the exorbital lacrimal gland are stellate with many thin radiating processes with tapered ends that terminate freely. MECs in the sublingual gland are characterized by a number of broad and extensive cellular processes. MECs in the submandibular gland are similar in appearance to those of the exorbital lacrimal gland, but with more extensive cellular processes that form a more or less continuous network with those of the adjacent cells. No MECs were observed on the terminal portion of the parotid gland where the cells appear to be lodged on the intercalated duct. The relative surface area covered by MECs per terminal portion was also found to vary significantly, being 24% in the lactating mammary, 17% in the exorbital lacrimal, 48% in the sublingual, and 25% in the submandibular glands. The findings are discussed in relation to the physical properties of secretions in different glands.

Animals↗

PubMed1980

A scanning electron microscopic study of the atrioventricular bundle of the ferret.

Scanning electron microscopy was used to examine the three-dimensional morphology of atrioventricular (AV) bundle cells in the ferret heart. These cells are organized into fascicles with extensive intercellular contact between cells within a fascicle and less contact between cells of different fascicles. The cell surface shows conspicuous ridges and depressions, as well as smooth regions. The distribution of myofibrils within an AV bundle cell is not uniform. Mitochondria of these cells are oval to round, and randomly distributed throughout the sarcoplasm. Junctions between cells within a fascicle are often complex with processes at the end of one cell interdigitating with those of another. In the proximal AV bundle, located above the anulus fibrosus, a small number of large cells are interspersed among the AV bundle cells.

Animals↗

PubMed1977

Rabbit ileal mucosa exposed to fatty acids, bile acids, and other secretagogues. Scanning electron microscopic appearances.

Segments of rabbit ileum were examined by scanning electron microscopy (SEM) after exposure to various compounds known to stimulate fluid secretion in the small intestine. After perfusion with ricinoleate (castor oil) at a 10 mM concentration, striking changes were observed at villus tips and on the apicolateral surfaces of villi; erosions at tips were confirmed by light microscopy of the same pieces of tissue examined by SEM. The appearances after ricinoleate were reversed in part during perfusion with control buffer for 2 hr. Statistical comparisons between control perfused, treated, and reversal tissues showed that the "damage" produced by ricinoleate, and its reversal, was significant statistically. Tissues treated with other intestinal secretagogues, oleic acid (10 mM), deoxycholic acid (4 mM), cholic acid (4 mM), dioctyl sodium sulfosuccinate (6 mM), and cholera toxin (1 microgram/ml) also showed surface changes by SEM. Fluid secretion, produced by an osmotic agent (mannitol) was not associated with "damage." Changes in structure of the mucosal surface after exposure to intestinal secretagogues should be considered as one possible mechanism of impaired fluid transport.

Animals↗