• The Korean Journal of Zoology
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• v.28 no.3
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• pp.194-208
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• 1985

The ultrastructure of the integumental epidermis of Korean planaria (Dugesia japonica) is studied by light microscope, scanning electron microscope and transmission electron microscope. The planaria has mono-layered integumental epidermis in which most of cells exhibit irregularly columnar shape. The epidermal cells of the integument are classified into six types on the basis of cytochemical and ultrastructural characteristics. 1) Ciliated epithelial cells: These cells have cilia in their free surfaces. The axonemes of cilia exhibits fundamental 9+2 microtubular pattern. 2) Eosinophilic cells: These cells contain a few large eosinophilic granules. The core of eosinophilic granule is consisted of sparsely dispersed fibrillar structures in relatively electron-lucent ground material. 3) Mucous cells: These cells are filled with irregularly shaped, PAS-positive mucous granules which have an average size of $0.8\\times0.3 \\muM$. 4) Rhabdite-forming cells: These cells possess a few strongly-eosinophilic large rhabdite granules. The rhabdite granules are synthesized either in the rhabdite-forming cells which constitute integumental epidermis or in the corresponding cells which are developed in the parenchyma and later transferred to epidermal cells of integumental epidermis through basement membrane. 5) A-type of basophilic granule cells: These granule cells possess round or irregularly-shaped granules which are strongly stained with Alcian blue. These electron-dense granules have an average size of $1.5\\times1.0 \\muM$. This type of cells is derived from parenchymal tissue. 6) B-type of basophilic granule cells: These basophilic granule cells with PAS-positive granules, are found in the epidermis of lateral body wall. The granules, which are about $0.7\\times0.4 \\muM$ in size, occupying most part of this cell type are originated from the parenchyma.

• Toxicological Research
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• v.7 no.2
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• pp.209-229
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• 1991

In the epidermis of skin, a fine balance exists between proliferating progenitor cells and terminally differentiating cells. We examined the effects of TGF-betas and retinoic acid (RA) on controlling this balance in normal human epidermal keratinocytes cultured under conditions where most morphological and biochemical features of epidermis in vivo are retained. Our results revealed marked and pleiotropic effects of both TGF-beta and RA on kerationcytes. In contrast to retinoids, TGF-betas acted on mitotically active basal cells to retard cell proliferation.

• Korean Journal of Weed Science
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• v.9 no.1
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• pp.46-55
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• 1989

Stomatal variation was observed at the Yeongnam Crop Experiment Station in 1988 using 42 rice cultivars and 30 weed species. The shape, density or size of stomata was varied depending on the species. Two general trends, however, were found that more number of stomata was found at lower leaf epidermis than upper leaf epidermis and stomata number was negatively correlated with stomata size. Aneilema japonica and Portulaca oleracea had the least number of stomata having 17-20 stomata per $m^2$ for upper leaf epidermis and 17-54 stomata for lower leaf epidermis while Polygonum conspicuum had the greatest number of stomata (449 for upper leaf epidermis and 511 for lower leaf epidermis). Soybean, Aeschynomene indica, Ludwigia prostrata and Lactuca indica had the smallest in stomata size while the biggest stomata was found at P. oleracea and A. Japonica that had the least number of stomata. Cyperus species such as C. difformis, C. iria and C. serotinus had no stomata at upper leaf epidermis. The stomata were distributed only at lower leaf epidermis for these species. Potamogeton distinctus, on the other hand, had stomata almost at upper leaf epidermis and thus, hardly found the stomata at lower leaf epidermis. Among rice cultivars, Tongil-type had the greatest number of stomata followed by Indica-type and Japonica-type, in order. Cultivars released after 1960 had more stomata than cultivars released before 1960 for Japonica-type cultivars while stomata size had reversed trend. Jinheung had the least number of stomata (${\fallingdotseq}$ 150 per $mm^2$) while Yushin had the greatest number of stomata (350 for upper and 449 for lower leaf epidermis, respectively) among rice cultivars. Other cultivars having more than 350 stomata per $mm^2$ were Samgangbyeo, Milyang 23, Woonbongbyeo, etc.

• Applied Microscopy
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• v.21 no.2
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• pp.96-116
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• 1991

The authors studied the morphological distinctions of each of the epidermal layers and the time of appearance of the keratohyalin granules and tonofilaments by the processing of development. The skins were obtained from fetal rats at the age of 14th, 16th, 17th, 18th, 19th and 20th day of gestation, of 1st and 3rd day of neonatal life and of 4th week after birth. The specimens were staind with uranyl acetate and lead citrate. The results obtained were as follows. 1. On the 16th-gestation day, the intermediate layer which contained numerous ${\alpha}-and\;{\beta}$-glycogen particles was appeared, and hemidesmosomes and desmosome were observed as well. 2. Tonofilaments were first observed on the 17th gestation day. 3. Above-mentioned intermediate layer was differentiated into the granular layer and the spinous layer on the 18th-gestation day. Keratohyaline granules were appeared in association with the ribosomes and the tonofilaments and the compound granules were lipoid granules which were surrounded by ribosomes at the periphery. 4. Ultimately, keratinization began to take place from the 20th-gestation day. At the age of 4th week, the thickeness of epidermis and the amount of keratohyaline granule and tonofibrils were decreased. It is consequently suggested that in the differentiation process of the rat epidermis, keratinization begins after formation of hemidesmosomes and desmosomes, from which the tonofilaments are formed and after keratohyaline granules are formed. Therefore appearance of the keratohyaline granules and formation of the tonofilament appears to have a close relations with the keratinization process of the rat epidermis.

• Korean Journal of Veterinary Research
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• v.34 no.4
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• pp.787-799
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• 1994

To elucidate morphologic lesion of porcine exudative epidermitis which is occurred sporadically in Korea, Staphylococcus hyicus subsp. hyicus isolated from the naturally affected pigs was inoculated to suckling pigs. The infected piglets were observed grossly and histopathologically. Although affected piglets were taking acute, subacute, or chronic course, some piglets suffered from chronic disease showed poor prognosis and marked growth depression. Affected peglets had erythematous skin on the face, ear, and abdomen and these localized lesions appear as brownish spots of exudative epidermitis and fromed crust in the early stage. But, after this stage, the skin were covered by viscous greasy exudate and formed blackish brown crust and appeared fissures and hypertrophy. Grossly, there has been hemorrhage with the removal of crust-like materials of epidermis and edematous subcutis. The superficial lymph nodes were edematous and swollen or congested and hemorrhagic. Some piglets had swollen ureters, cysts in the renal cortex, or polyarthritis. A few cases had mild edematous swelling of kidney, intestinal catarrh and congestion of brain. Microscopically, skin lesions had detachment of keralinized layer and parakeratosis of epidermis, hydropic degeneration of epidermal cell, and retrogressive degeneration of hair root sheath. Dermis had edema, and infiltration of neutrophils and mononuclear cells. As the disease was proceeded, there was marked perivasculitis with lots of mononuclear inflammatory cells. More chronic lesions formed granuloma-like bodies(nodules) due to more mononuclear, perivascular inflammatory cell infiltration and proliferation of fibroblast. Lots of plasma cells and eosinophils were also present in dermis. Epidermis was hyperplastic by proliferation of basal cells stratum germinativum and epidermal pegs often extended into the dermis. In secondary infection, lots of neutrophils could be seen in epidermis and derms. Kidney had neutrophilic infiltration, necrotic and cystic glomeruli, and dilation of renal tubules and ureters. Purulent arthritis was sometimes observed in joints. Three days old mice administrated Staphylococcus hyicus subsp hyicus subcutaneously before had focal congestion and hemorrhage, necrosis, and subcutaneous edema of the skin. This observation was also seen in the study of mice administrated exfoliatin toxin of Staphylococcus which evoked human staphylococcal scalded skin syndrome.

• Korean Journal of Ichthyology
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• v.19 no.2
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• pp.120-127
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• 2007

To investigate the skin of the flat-headed goby, Luciogobius guttatus, it was used 8 body regions such as the head, the upper and lower jaw, the chin, the back, lateral region, abdomen, and the operculum. The epidermis consisted of three layers: the outermost layer, middle layer and stratum germinativum (basal layer). The outermost layer consisted of rather flattened cells arranged in 1 to 4 layers and mucous cells. The middle layer consisted of large epidermal cells occupying the height of the epidermis with 1 to 10 layers, causing a web-shaped structure. Due to the large epidermal cells of the middle layer, L. guttaus had a thick epidermis. The large epidermal cell contains tonofilaments, lucent contents, and desmosome. The basal layer was comprised of a single layer having cuboidal cells. A large number of fine blood capillaries were found just under the basal layer. The dermis consisted mostly of stratum compactum with numerous blood capillaries but had no scale.

• Applied Microscopy
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• v.42 no.2
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• pp.95-103
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• 2012

The cell surface sculpture of the plant epidermis has received great interest recently. It has also been an active area of research, as the biological microstructures of the surface, such as papillae and waxes, exhibit several unique properties, including self-cleaning character; namely the "Lotus effect" first described in the leaves of the lotus, Nelumbo nucifera. The Lotus effect is the phenomenon in which the super-hydrophobic and water-repellent nature of lotus leaves allow water drops to run off easily on the surface in a rolling and sliding motion thereby facilitating the removal of dirt particles. It is well-known that surface roughness on the micro- and nanoscale is a primary characteristic allowing for the Lotus effect. This effect is common among plants and is of great technological importance, since it can be applied industrially in numerous fields. In the present study, Nelumbo nucifera leaf and stem epidermal surfaces have been examined with a focus on the features of papillae and wax crystalloids. Both young and mature Nelumbo nucifera leaf epidermis demonstrated the Lotus effect on their entire epidermal surface. The central area of the upper epidermis, in particular, formed extremely papillose surfaces, with an additional wax layer, enabling greater water repellency. Despite the presence of wax crystalloids, epidermal surfaces of the lower leaf and stem lacking papillae, were much more easily wetted.

• Applied Microscopy
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• v.32 no.2
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• pp.121-129
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• 2002

The structure of integumentary epidermis is studied in the bastard halibut, Paralichthys olivaceus based on the light and transmission electron microscope. Epidermal layer consists of supporting cells, unicellular glands and accessory cells. The supporting cells were classified into superficial cell, intermediated cell and basal cell. Superficial cell of epidermal layer is squamous or cuboidal and the surface is covered with numerous microridges. The supporting cells are connected to another cell with membrane interdigitations and desmosmes. And tonofilaments are developed in the cortical cytoplasm. Gland cells are classified into mucous cell and club cell. By the histochemical studies of the epidermal secretions the mucous materials are identified as neutral polysaccharides. Club cell has numerous vacuoles and microfilaments in the cytoplasm. Also chloride cells are observed in the epidermis, it cytoplasm is occupied numerous mitochondria.

• Korean Journal of Plant Resources
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• v.8 no.3
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• pp.303-318
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• 1995

Microscopic structures of epidermis and palynology and isozyme analysis were examined to find out the intergeneric and interspecific relationships and consequently to confirm the position of Hanabusaya aiatica as an endemic genus among 4 genera and 9 species belonging to the Hanabusaya asiatica, Korean endemic, and its allied groups. In the examination of microscopic structures of epidermis, cell patterns of perianth and ultrastructure of seed coat were found to be useful characters for the identification of the 4 genera and 9 species. Palynological characters such as microscopic structure and overall morphology of pollen grains were, however, not enough to distinguish them because of the great variabilities in these traits. Isozyme analysis showed that H. asiatica was very closly related to Campanula punctata and C. takesimana, though there were variations among populations and collected areas in some classified groups, depending on classified groups. Based on these results, the position of H. asiatica as an endemic genus was well confirmed.

• Journal of radiological science and technology
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• v.43 no.4
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• pp.259-264
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• 2020

Radiation causes radiation hazards in the human body. In Korea, a case of radiation necrosis occurred in 2014. In this study, the scatter and shielding efficiency according to lead shielding were classified into epidermis and dermis for 0.511 MeV used in nuclear medicine. In this study, experiments were conducted using the slab phantom that represents calibration and the dose of human trunk. Experimental results showed that the shielding rate of 0.25 mmPb was 180% in the epidermis and 96% in the dermis. Shielding at 0.5mmPb showed shielding rates of 158%in the epidermis and 82% in the dermis. As a result of measuring the absorbed dose by subdividing the thickness of the dermis into 0.5 mm intervals, when the shielding was carried out at 0.25 mmPb, the dose appeared to be about 120% at 0.5 mm of the dermis surface, and the dose was decreased at the subsequent depth. Shielding at 0.5 mmPb, the dose appeared to be about 101% at the surface 0.5 mm, and the dose was measured to decrease at the subsequent depth. This result suggests that when lead aprons are actually used, the scattering rays would be sufficiently removed due to the spaces generated by the clothes and air, Therefore, the scattered ray generated from lead will not reach the human body. The ICRU defines the epidermis (0.07), in which the radiation-induced damage of the skin occurs, as the dose equivalent. If the radiation dose of the dermis is considered in addition, it will be helpful for the evaluation of the prognosis for radiation hazard of the skin.