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This paper describes four investigations of the olfactory mucosa of the brown trout: 1) the ultrastructure of the olfactory mucosa as revealed by scanning (SEM), conventional transmission (TEM), and high voltage (HVEM) electron microscopy; 2) light and electron-microscopic investigations of retrograde transport of the tracer macromolecule horseradish peroxidase (HRP) when applied to the cut olfactory nerve; 3) SEM and TEM investigations of the effects of olfactory nerve transection on cell populations within the olfactory epithelium; and 4) ultrastructural investigations of reversible degeneration of olfactory receptors caused by elevated copper concentrations. The trout olfactory epithelium contains five cell types: ciliated epithelial cells, ciliated olfactory receptor cells, microvillar olfactory receptor cells, supporting cells, and basal cells. The ciliated and microvillar olfactory receptor cells and a small number of basal cells are backfilled by HRP when the tracer is applied to the cut olfactory nerve. When the olfactory nerve is cut, both ciliated and microvillar olfactory receptor cells degenerate within 2 days and are morphologically intact again within 8 days. When wild trout are taken from their native stream and placed in tanks with elevated copper concentrations, ciliated and microvillar cells degenerate. Replacement of these trout into their stream of origin is followed by morphologic restoration of both types of olfactory receptor cells. Ciliated and microvillar receptor cells are primary sensory bipolar neurons whose dendrites make contact with the environment; their axons travel directly to the brain. Consequently, substances can be transported directly from the environment into the brain via these "naked neurons." Since fish cannot escape from the water in which they swim, and since that water may occasionally contain brain-toxic substances, the ability to close off--and later reopen--this anatomic gateway to the brain would confer a tremendous selective advantage upon animals that evolved the "brain-sparing" capacity to do so. Consequently, the unique regenerative powers of vertebrate olfactory receptor neurons may have their evolutionary origin in fishes.
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PMID:Ultrastructural neurobiology of the olfactory mucosa of the brown trout, Salmo trutta. 139 70

The lymphocytes and antigen presenting cells in lymph node of rats stimulated by He-Ne laser acupuncture were observed by using TEM and SEM to investigate the ultrastructural changes of them. There were numerous activated T-cells which showed deeply indented nucleus, abundant small void mitochondria and free ribosomes in the paracortex area. The B-cells were gradually differentiated into large lymphocytes, immature and mature plasmatic cells which with a lot of rough endoplasmic reticulum. They were prominently increased in the pulp area. The macrophages had short processes with numerous folds and microvilli and tended to neighboring lymphocytes. The nucleus pores were increased. There were a lot of pinocytosomes, phagosomes, lysosomes in various size of macrophages. The bundles (5-6 nm in diameter) of microfilaments of the macrophages were extended from the cytoplasm to the processes. The interdigitating cells which contained the characterized single layer of rER, numerous polysomes, mitochondria and well-developed Golgi-complex were closed to macrophages and lymphocytes. In conclusion the activities of the cellular immunity and humoral immunity were enhanced by laser.
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PMID:[Effect of He-Ne laser acupuncture on lymph-nodes in rats]. 139 58

Patients with chorea-acanthocytosis exhibit symptoms of self-biting, choreic movement, and acanthocytosis, but not dementia. The mechanism of choreic movements is still unknown. In order to clarify the etiologic mechanism underlying these movements, we evaluated the erythrocyte membrane in one patient with chorea-acanthocytosis. A 35-year-old female was admitted to Saitama Medical School Hospital because of involuntary movements. She was alert, well-oriented, and had no gross memory defects. She had slurred speech, choreic movements and lip biting. Laboratory examination showed acanthocytes in her peripheral red blood cells, normal serum lipid values, and caudate atrophy on her brain CT scan. In analyzing the acanthocytes, we initially evaluated the size of the acanthocyte population by incubating her red blood cells with plasma. The cell population approximately doubled after 2 hours incubation. Next we examined the protein composition of erythrocyte ghost by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). There was no significant difference between the patient's erythrocyte ghosts and those of a control. Then we investigated morphological changes in the patient's erythrocyte by scanning and transmission electron microscopy (SEM and TEM). SEM showed the typical acanthocyte shape. The quick-freeze, freeze-substitution method confirmed that the routine TEM section was not artifactual, and was in fact in accurate reflection of the actual features of acanthocytes. TEM of the sections prepared from erythrocyte ghosts demonstrated that spectrin tended to be accumulated in the thorn region. Furthermore, TEM of quick-freeze, deep-etched replica of the ghost revealed more clearly a spectrin network densely packed on the inner hydrophilic surface.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Studies on the erythrocyte membrane skeleton in a patient with chorea-acanthocytosis--theoretical speculation on the mechanism of neurological involvement]. 141 52

The eggshell structure of four sandfly species: Phlebotomus perniciosus Newstead, P.perfiliewi Parrot, P.papatasi Scopoli and P.duboscqi Neveu-Lemaire, was examined by scanning and transmission electron microscopy (SEM and TEM). At the TEM level, the eggshell appears to have a homogeneous vitelline envelope and a thick chorion. At SEM level, the eggshell of all species is characterized by the outer chorion forming a series of fifteen to twenty longitudinal sinuous ridges, cross-linked in places to form a pattern of polygons, each line of the chorion consisting of columns arranged in a palisade. The aeropyle region of the egg is described for the first time in phlebotomine sandflies. Specific characters of the eggshell topography are described for distinguishing between these and other species of Phlebotomus.
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PMID:Ootaxonomy and eggshell ultrastructure of Phlebotomus sandflies. 142 99

Cytolysis of host cells by pathogenic Entamoeba histolytica can be blocked by specific lysozyme inhibitions and is recently reported to be enhanced by phosphoinositide (PI) signal transduction activation. However the mechanistic relationship between PI second messenger targets and massive lysosomal secretion needed to achieve rapid host cell lysis is unclear. We have previously shown that intracellular alkalinization associated with activated PI hydrolysis produces a massive endocytosis of huge proportions which would force a corresponding exocytosis for the maintenance of overall cell dimensions. These endosomes are processed by primary lysosomes. Apparently then, the massive exocytosis secretory pathway could provide the means for the ejection of lysozymes over target cells. We show here using human Chang liver cells that intracellular alkalinization produced large surface pittings similar to those seen in pathogenic E. histolytica in a rounded state. The SEM profile is correlated with the TEM profile of large endosomes containing extracellular debris and endosomes associated with primary lysosomal vesicles, which could support the notion that some of the pittings seen in the rounded Chang cells and the pathogenic amoebae are exit portals for endosome-lysosomes.
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PMID:Human Chang liver cells show large surface openings and endocytic channels that resemble those in the amoeba. 142 18

The effect of biomaterials on the activation of human neutrophils was studied. Human neutrophils were incubated with F-75 cobalt-based alloy or polystyrene microspheres of a nonphagocytosable size with two times total neutrophil plane surface area. Scanning and transmission electron microscope (SEM, TEM), energy dispersive x-ray microanalysis (EDX), and graphite furnace atomic absorption spectroscopy (GFAAS) were used to analyze changes in cellular morphology and metal content. This report presents evidence that human PMNs display morphological changes related to foreign material challenge, including activation on F-75 bead surfaces, pinocytosis of corrosion products, formation of intracellular vacuoles, degranulation, etc. Moreover, when PMNs were present, the corrosion release rate of F-75 increased as much as three times over cell-free controls.
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PMID:Human neutrophil response to short-term exposure to F-75 cobalt-based alloy. 142 68

We examined the fine structure of the upper and lower surfaces of stratified squamous epithelial cells in the skin of frogs (Hyla japonica). SEM revealed the upper surface of superficial cells covered with ramified microridges (type 3). The width of the microridges was 0.20-0.24 microns. Microridges found at the cell boundary were about 0.30 microns in width and a narrow furrow was seen between the two cells. The numerous oval disk-like structures (0.23 x 0.32 microns in diameter) covered the lower surface of these superficial cells. The upper surface of cells in the 2nd layer was covered with baculiform or ramified microridges (type 2 or 3). On the cell boundary, two linear microridges (0.23-0.27 microns in width) were parallelly arranged. The width of the microridges covering the upper cell surface was 0.09-0.10 microns. Microvilli-like processes with a height of 0.32-0.37 microns were interspersed among the microridges. Their tip formed an oval plane (0.23 x 0.31 microns), which corresponded to the size of the disk-like structures on the lower surface of the superficial cells. Desmosomes were observed on the tip by TEM. These findings show that the disk-like structures on the lower surface of the superficial cells are the sites of binding with the microvilli-like processes on the upper surface of the 2nd layer cells. The disk-like structures observed in the present study seem to be equivalent to the binding site on the upper surface of the surface cell layer of mammalian stratified squamous epithelium.
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PMID:Scanning and transmission electron microscopic studies on the upper and lower surfaces of the frog skin epidermal cells. 143 70

Amorolfine inhibited the in-vitro growth of Trichophyton mentagrophytes to some extent at a low drug concentration of 0.8 ng/ml. Corresponding to the growth inhibition, SEM studies revealed a slight modification of hyphal morphology, i.e. a waving of the hyphal surface. These morphological alterations were more extensive with increases in drug concentration and treatment period: collapsed and distorted hyphae and exfoliation of the surface of T. mentagrophytes occurred at 8 ng/ml and marked deformation and disruption of the hyphal structure at 80 ng/ml of amorolfine. TEM revealed thickening of the cell walls and the accumulation of electron-dense granular structures in both the wall and cytoplasm in thin-sectioned cells pretreated with 8 ng/ml or more of amorolfine, although the nuclear and mitochondrial architecture was not noticeably influenced. Cytoplasmic membranes and other membranous structures of organelles such as nuclei and mitochondria were disrupted or fused, thereby losing their essential physiological activity in hyphal cells pretreated with 80 ng/ml of amorolfine. The ultrastructural study thus supports the observation that morphological changes of T. mentagrophytes caused by amorolfine were associated with its growth-inhibitory and killing activity, which depended on the drug concentration and treatment time.
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PMID:Morphological changes associated with growth inhibition of Trichophyton mentagrophytes by amorolfine. 145 57

Research into improved adhesion of resins to tooth substrates has found that methacrylates with both hydrophobic and hydrophilic groups, like 4-methacryloxyethyl trimellitate anhydride (4-META), enhance monomer penetration into dentin pretreated with 10% citric acid and 3% ferric chloride (10-3). Scanning and transmission electron microscope (SEM and TEM) examinations revealed the formation of a transitional zone of resin-reinforced dentin, termed the hybrid layer. The 4-META adhesive resin impregnated the exposed collagen bundles with which it entangled to create the hybrid, essential to attaining high tensile bond strengths.
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PMID:Adhesive bonding with 4-META. 147 May 41

To evaluate and compare the pathogenesis of pseudo-intimal hyperplasia (PH) of venous and arterial prostheses, a segment of the inferior vena cava (n = 16) or abdominal aorta (n = 16) was substituted by a 3 mm internal diameter polytetrafluoroethylene tube graft (PTFE, 3 cm long, 30 microns in nodal distance) in albino rabbits. At designated time intervals (3-28 days) after the replacement, graft patency was examined and the dry weights of the intraluminal deposits measured as an indicator of the degree of PH. The harvested grafts were then subjected to an ultrastructural analysis by means of light microscopy (LM), and scanning electron and transmission electron microscopy (SEM, TEM). All the grafts remained patent during the entire observation period. The PH judged by the dry weight was significantly more extensive in the venous than in the arterial prostheses. The PH on day 28, observed by light microscopes was apparently most extensive in the mid-portion of venous prostheses but in the arteria prostheses it was mostly seen at the anastomotic sites. The lining of the intraluminal surface of the prostheses with endothelial-like cells observed by SEM was faster and more extensive in venous than in arterial prostheses. The process of PH in venous prostheses observed by TEM may be divided into the following steps: early thrombosis, phagocytosis of the thrombus, appearance of fibroblasts, growth of endothelial-like cells, appearance of smooth muscle cells, and pseudointimal thickening and proliferation of fibroblasts producing collagen fibrils. The process in arterial prostheses was essentially identical to that in venous prostheses but was much slower and less extensive. From these observations, it was concluded that the formation of PH occurs much faster in venous than in arterial prostheses, although the mechanism of PH is mostly identical in venous and arterial prostheses.
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PMID:Ultrastructural analysis of pseudo-intimal hyperplasia of polytetrafluoroethylene prostheses implanted into the venous and arterial systems. 149 39


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