• Korean Journal of Metals and Materials
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• v.50 no.3
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• pp.212-217
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• 2012

This study was carried out to investigate the effect of the hot forging ratio on the microstructure and mechanical properties of ultra high carbon steel. The microstructure of ultra high carbon steel with 1.5%wt.C consisted of a proeutectoid cementite network and acicular microstructure in pearlite matrix. With increasing hot forging ratio, the volume and thickness of the network and acicular proeutectoid cementite decreased. Lamella spacing and the thickness of eutectoid cementite decreased with increasing hot forging raito, and were broken up into particle shapes, which then became spheroidized. When the forging ratio was over 65%, the network and acicula shape of the as-cast state disappeared. With increasing hot forging ratio, hardness, tensile strength, elongation and impact value were not changed up to 50%, and then rapidly increased with the increase of the forging ratio.

• Journal of fish pathology
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• v.35 no.2
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• pp.231-239
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• 2022

In this study, imported ornamental goldfish (Oranda and black moor) with high mortality was investigated with histopathological analysis. Fishes showed clinical symptoms characterized by gill necrosis and cumulative mortality ranging from 60% to 90% within a month after import from Thailand and China in 2021. CyHV-2 was detected in gill, kidney, spleen and liver of goldfishes. Histopathological analysis revealed epithelial necrosis, intranuclear inclusion bodies associated with viral symptoms in epithelial cell, macrophage infiltration and vacuolation in secondary lamella. In addition, disseminated granuloma formation was observed in various organs such as kidney, heart and mesenchymal membranes. These lesions refer to coinfections with CyHV-2 and other pathogens that cause chronic inflammation, which leads to mortality. Therefore, early disease monitoring needs to reduce the mortality when ornamental goldfish is imported.

• Korean Journal of Environmental Biology
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• v.42 no.1
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• pp.1-14
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• 2024

This study evaluated the risk of single and combined exposure to microplastics in zebrafish (Danio rerio) through biomarkers, such as survival rate, excretion rate, and histological alterations of organ systems. The experimental groups were the control(Cont.), single microplastics exposure group(MPs, 1.83%/fish total weight(g)), the copper group(Cu, 21.6 ㎍ L^-1), and a group with combined exposure to MPs and copper (MPs^*Cu). The experiment was conducted with individual exposure (7 days) for MP excretion rate analysis and group exposure (14 days) for biomarker analysis. The daily excretion rate of MPs tended to decrease in a time-dependent manner. The copper concentration in the body was not significantly different between single and combined copper exposure. The degeneration of mucous cells in the skin, capillary dilation of the gill lamella, increased intestinal mucous, hepatocyte hypertrophy, and the degeneration of glomeruli and renal tubules were observed in all exposure groups. These histological alterations showed the highest tendency in the MPs^*Cu group. In this study, the changes in biomarkers were attributed to the single effect of copper or the combined effect of copper and MPs rather than being solely influenced by MPs.

• Applied Microscopy
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• v.39 no.4
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• pp.319-324
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• 2009

Morphology of the gill in Lateolabrax japonicus was investigated after staining the gill, as a result, we found the gill is composed of gill raker, gill arch, gill filament and gill lamellae. The number of gill raker was 7~10 in the upper and 13~18 in the lower. Ultrastructure of the gill in Lateolabrax japonicus were examined by means of the light and transmission electron microscopes. The gill have primary filament and secondary filament (lamellae). The following cells are identified and described: pavement cell, pillar cell, blood cell, mucose cell and chloride cell etc. Simple epithelial layer consists of squamous epithelium contained large nucleus, intracellular organelles etc. and the surface is covered with some of microridges. The lamella pillar structures are characterized by the axial microtubules and lateral membrane interdigitations. The mucous cells were globular in shape, and had almost the mucous granules of same size with various electron density. Chloride cells contain a lot of mitochondria and specifically developed tubular systems.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.23 no.3
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• pp.92-96
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• 1997

Nowadays, ceramides have been found to be an important component in the outermost layer of the skin - the stratum corneum. It is undersrood that ceramides play an important role in structure and maintenance of the interellular lipid lamella structure in the SC layer. Thus, many efforts have been made by the cosmetics and pharmaceutical industries to get human skin-identical ceramides or pseudoceramides which show similar performance with natural ceramides. The purpose of our study was to systhesize new pseudoceramides via an effective and economical systhetic pathway and to show their performance of skin restoratio. Four kinds of the new pseudoceramides were synthesized by the reaction of alcoholic amine and alkyl ketene dimer. First of all, PC-4 and PC-5 were synthesized by the reaction of 3-amino-1,2-propanidiol and serinol with alkyl ketene dimer respectively. After that, PC-4R and PC-5R were produced by changign kitone group at $\beta$-position to amide bond of above synthesized PC-4 and PC-5 into hydroxyl group using NaBH4 respectively. Their expected structures were conformed by the NMR, IR spectra, and elemental analysis. A study to show the restoration effectiveness was performed in which human skin was pretreated with high concentration of SDS surfactant solution. Using 0.5% solution of above synthesized pseudoceramides, there was the significantly faster restoration of the damaged than that of placebe itself treatment.

• Journal of Yeungnam Medical Science
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• v.33 no.2
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• pp.146-149
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• 2016

Heterotopic bone formation in the gastrointestinal tract is a rare phenomenon. Most reported cases were associated with benign and malignant neoplasms, except for a case in which heterotopic bone formation was found in a patient with Barrett's esophagus. The exact pathogenesis of the disease has not yet been established. However, most heterotopic bones found in the gastrointestinal tract were associated with mucinproducing tumors of the appendix, colon, and rectum. Inflammation may also play a role in osseous metaplasia in a case with bone formation at the base of an ulcer in Barrett's esophagus. Here, we report on a patient with heterotopic bone formation in normal gastric cardiac mucosa. A 50-year-old female visited our hospital for a routine health examination. She had no gastrointestinal symptoms, and her physical examination, blood test, X-ray, urine, and stool examination results were normal. A 0.3 cm sized polypoid lesion located just below the squamocolumnar junction was observed on upper gastrointestinal endoscopy. A piece of biopsy was taken. Histologically, a lamella bone trabecula and chronic inflammatory cells were observed in the gastric cardiac mucosa. The follow-up endoscopy performed one month later showed no residual lesion.

• The Journal of Pediatrics of Korean Medicine
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• v.32 no.3
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• pp.90-99
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• 2018

Objectives Hwangnyeonhaedok-tang is a Korean herbal medical treatment that removes toxic heat, fever and inflammation. The purpose of this study was to investigate the effect of Hwangnyeonhaedok-tang treatment on the relief of atopic dermatitis (AD) through regeneration of skin lipid barrier. Methods Male NC/Nga mice (20 g, 6 week age) were used. Each 10 mice were allocated to the control group (Ctrl), the AD-induced with no treatment group (AE), and the group which induced AD after administering Hwangnyeonhaedok-tang extract (HT). To induce AD-like skin lesions, sodium dodecyl sulfate (SDS) (Sigma-Aldrich, USA) was rubbed on the back of each mouse to remove the lipid lamella of the stratum corneum, and Dermatophagoides (D.) farinae crude extract was applied. HT group was orally administered Hwangnyeonhaedok-tang after induction of AD. IL-4 IL-13, $p-I{\kappa}B$, iNOS, Sudan Black B (SB), loricrin, and filaggrin were observed to confirm the effect. Results In HT group, AD skin score was decreased by 46%. The cytokine IL-4 and IL-13, which can identify Th2 differentiation, was reduced by 73% and 58% each. Anti-inflammatory effects were observed in $p-I{\kappa}B$ and iNOS by 69% and 54%, respectively. Finally, SB showed that the regeneration of the lipid layer and the increase of the regeneration power of loricrin and filaggrin were increased by 437% and 464%, respectively. Conclusions From the study result, we observed that Hwangnyeonhaedok-tang treatment alleviates AD by decreasing skin score, reducing Th2 differentiation, inducing anti-inflammatory, and increasing skin lipid barrier regeneration. Thus, Hwangnyeonhaedok-tang treatment would be considered as an effective AD relieving treatment.

• Korean Journal of Plant Resources
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• v.14 no.2
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• pp.102-107
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• 2001

This study was carried out to explore for the possibility of recycling the pine wood sawdusts for the substrate for enokitake (Flammulina velutipes) cultivation. The wood species of sawdusts cultivated for enokitake mushroom were identified mostly as hard pine (Pinus spp.). Distribution of enokitake hyphae was restricted to ray parenchymas and tracheids exposed to fungi. Nevertheless, degree of cell wall degradation by enokitake was slight. Light microscopic observation showed the thinning of secondary cell wall in some tracheids. Under polarized microscopy the 1()ss of birefringence was observed only in a few latewood tracheids. All the middle lamella remained intact. The present work showed clearly that pine sawdusts used as substrate for enokitake cultivation held enough cell wall materials for mushroom cultivation. The relative resistance of softwood cell walls against enokitake fungus was also discussed.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.20 no.2
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• pp.173-183
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• 1998

$TGF-{\beta}$ is one of growth factors that may be involved in the formation of bone and cartilage. Multiple studies demonstrate that $TGF-{\beta}$ is involved in regulating cell proliferation, differentiation and matrix synthesis, events observed in frature healing. The apperance of $TGF-{\beta}$ in the fracture during healing was evaluated by immunohistologic localization of $TGF-{\beta}$ using antibody. Twenty Sprauge-Dawley strain white male rats, each weiging about 150grams were used and divided two groups. The one group, the $2{\times}2mm$ bony defect was formed in the right femur. The other group, $4{\times}2mm$ bony defect was formed in right femur. Both group were sacrificed at 3day, 1, 2, 3, 4 week and femur were harvested, paraffin sections were stained with H & E, MT stain, immunihistochemical staining with $TGF-{\beta}$ antibody and observed under light microscope. The result were as follows: 1. New bone formation and cartilagenous tissue was seen at 3day. And in the $2{\times}2mm$ bony defect group, $TGF-{\beta}$ stained the cell surounding new bone. 2. The osteoclast and trabecular was seen at 1week. $TGF-{\beta}$ stained the osteoblast and in the $2{\times}2mm$ bony defect group was stained more than $4{\times}2mm$ bony defect group. 3. The lamella bone and trabecule was seen from 3, 4week, and $TGF-{\beta}$ stained almost negative. From the above finding, we could concluded that $TGF-{\beta}$ stained the osteoblast at early stage and 1week, the peak stain was seen from 1week, and then decreased, almost negative stain was seen at 3, 4week.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.3
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• pp.281-285
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• 2011

Sinus floor elevation is a predictable and standard procedure for the treatment of the posterior maxilla before insertion of dental implants. Although overall complication rates are low, complications can occur including sinus membrane perforation, infection of sinus, swelling and hemorrhage. The most common complication is membrane perforation. Recently, various techniques and materials for repair of perforation to the sinus membrane have been proposed. The purpose of this article is to report on various techniques and materials that can be used for repair of perforations to the sinus membrane. The search protocol used was the following electronic database: Pubmed, with a time limit from 1998 to 2009. The key words such as 'sinus lift', 'sinus augmentation', 'sinus floor elevation', 'sinus graft', 'sinus perforation', 'repair of sinus perforation' and 'repair of sinus membrane' were used, alone and in combination, when searching the database. Various techniques have been proposed to manage of perforation of sinus membranes. These include that the use of collagen membranes, demineralized freeze-dried human lamellar bone sheets, processed human allografts, lamella bone, buccal fat pads and suturing. Implant success rate ranges from 69.9% to 98.9%.