• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.04a
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• pp.117-120
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• 2003

Electro-micromechanical techniques were applied using four-probe method for carbon nanotube (CNT) or nanofiber (CNF)/epoxy composites with their content. Carbon black (CB) was used to compare with CNT and CNF. The fracture of carbon fiber was detected by nondestructive acoustic emission (AE) relating to electrical resistivity for double-matrix composites test. Sensing for fiber tension was performed by electro-pullout test under uniform cyclic strain. The sensitivity for fiber damage such as fiber fracture and fiber tension was the highest for CNT/epoxy composites, and in CB case they were the lowest compared with CNT and CNF. Reinforcing effect of CNT obtained from apparent modulus measurement was the highest in the same content. The results obtained from sensing fiber damage were correlated with the morphological observation of nano-scale structure using FE-SEM. The information on fiber damage and matrix deformation and reinforcing effect of carbon nanocomposites could be obtained from electrical resistivity measurement as a new concept of nondestructive evaluation.

• Journal of Embryo Transfer
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• v.23 no.1
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• pp.19-24
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• 2008

The purpose of this study was to compare the efficiency of slow freezing with that of vitrification method for the cryopreservation of human embryos. Human embryos were derived from in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) and the mixed solution of propanedial (1.5, 1.0, 0.5M PROH) and sucrose (0.1M), ethylene glycol (7.5, 15%), dimethyl sulfoxide (7.5, 15% DMSO), sucrose (0.5, 1.0M) and SPS (Serum Protein Substitute) was used for a cryoprotectant for slow freezing and vitrification solution, respectively. Rates of recovery after thawing, morphological normality, post-thaw viability, arrest, morphological abnormality and preimplantation development were compared between two protocols. After freezing-thawing, recovery and survial rate of slow freezing was (88.6% and 73.4%), whereas vitrification was (99.2% and 96.2%) (p<0.05). The arrest rate of slow freezing was significantly lower compared with those of vitrification(8.7% vs 29.9%) (p<0.05). Preimplantation development to the 2-cell (83.8% vs 67.7%), 4-cell (69.0% vs 47.2%) and 8-cell (62.4% vs 37.8%) stages 24, 48 and 72 h after thawing, respectively, were higher in the slow freezing than the vitrification. After slow freezing and vitrification of human embryo at 2-8cell stage, the rate of recovery rate, survival rate and partial damage rate were 92.0% vs 100%, 80.4% vs 96.2% and 52.2% vs 19.0%, respectively. And partial damage rate was significantly lower than those of slow freezing method (p<0.05). These results demonstrate that a slow freezing using PROH is more efficient than a vitrification for cryopreserving the human zygotes, although the vitrification yielded better recovery, survival and partial damage of frozen-thawed 2-8 cell stage embryos than slow freezing method.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.2
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• pp.169-179
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• 2023

Purpose : Although human periodontal ligament stem cells (hPDLSCs) are a supportive factor for tissue engineering, oxidative stress during cell culture and transplantation has been shown to affect stem cell viability and mortality, leading to failed regeneration. The aim of this study was to evaluate the antioxidant and protective effects against cell damage of celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, and the antioxidant signal of hPDLSCs in H₂O₂-induced oxidative stress. Methods : To induce oxidative stress in cultured hPDLSCs, H₂O₂ was used as an exogenous reactive oxygen species (ROS). Dose-dependent celecoxib (.1, 1, 10, or 100 µM) was administered after H₂O₂ treatment. WST-1 assay was used to assess cell damage and western blot was used to observe antioxidant activity of hPDLSCs in oxidative stress. Immunohistochemistry was performed for inverting the localization of the SOD and Nrf2 antibody. Results : We found that progressive cell death was induced in hPDLSCs by H₂O₂ treatment. However, low-dose celecoxib reduced H₂O₂-induced cellular damage and eventually enhanced the SOD activity and Nrf2 signal of hPDLSCs. Oxidative stress-induced morphological change in hPDLSCs included lowered the survival and number of spindle-shaped cells, and shrinkage and shortening of cell fibers. Notably, celecoxib promoted cell survival function and activated antioxidants such as SOD and Nrf2 by positively regulating the cell survival signal pathway, and also reduced the number of morphological changes in hPDLS. Immunohistochemistry results showed a greater number of SOD- and Nrf2-stained cells in the celecoxib-treated group following oxidative stress. Conclusion : By increasing SOD and Nrf2 expression at the antioxidant system, the findings suggest that celecoxib enhanced the antioxidative ability of hPDLSCs and protected cell viability against H₂O₂-induced oxidative stress by increasing SOD and Nrf2 expression in the antioxidant system.

• Journal of Digital Convergence
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• v.15 no.9
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• pp.533-541
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• 2017

In the rapidly changing 21st century, image management has become more important. Under these circumstances, as a lot of hair colors and beaching agents are used to create diverse hair colors, hair damage resulting from frequent chemical hair coloring has been inevitable. This study investigated how to reduce morphological changes in hair and hair damage after dividing hair into healthy hair('Group A') and damaged hair('Group B'), using the following bleaching agents: basic bleaching agent(a), beaching agent diluted with water(b), oil ingredient-added bleaching agent(c), water-shampoo mixed bleaching agent(d). The results found that even though hair damage can be prevented by a bleaching agent diluted with a mixture of diverse additives, there were better effects on hair texture in both 'Group A(4.83)' and 'Group B(4.41)' at a sensory test when hair was bleached with an addition of Camellia oil, according to blinded experiment, in particular. As a result, hair damage could be reduced. Therefore, this study expects that hair bleaching with an addition of Camellia oil to the mixture of a bleaching agent would bring the development of diverse new materials which can minimize hair damage as well as regulate hair brightness and make a contribution to the development of cosmetology market.

• Journal of Life Science
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• v.11 no.2
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• pp.126-132
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• 2001

Effect of Quartz porphyty(QP) on functional and morphological changes of the liver and kidney was studied in male common finch and white java sparrow fed with the basal diet(Control group) or experimental diet containing 3.0% QP(QP group) for 14 days. There was not significantly different morphological change of the liver upon light microscopic examination in common finch and white java sparrow between control group and QP group. Morphological change of renal tissue upon light microscopic examination in common finch and white java sparrow was not also significantly different between control group and QP group. The concentrations of serum creatinine, blood urea nitrogen, and nric acid as renal functional parameters of common finch and white java sparrow were not significantly different in the both groups. The activity of glutamic oxaloacetic transaminase(GOT) as hepatic functional parameter in common finch was significantly higher in the QP group($\rho$<0.05), whereas the activity of glutamic pyruvic transaminase(GPT) as hepatic functional parameter in common finch was not significantly different in the both groups. The activities of GOP and GPT in white java sparrow were not significantly different in the both groups. The morphologic findings and functional parameters of the liver and kidney observed in common finch and white java sparrow fed with 3.0% QP diet showed evidence of slightly liver damage accompanied with increased release of enzyme and fatty change of the hepatocytes in common finch, suggested that the tissues in some animals can be damaged by feeding a diet supplemented with 3.0% QP.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.3
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• pp.217-225
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• 2021

Neuropathic pain (NP) that contributes to the comorbidity between pain and depression is a clinical dilemma. Neuroinflammatory responses are known to have potentially important roles in the initiation of NP and depressive mood. In this study, we aimed to investigate the effects of paeoniflorin (PF) on NP-induced depression-like behaviors by targeting the hippocampal neuroinflammation through the toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) signaling pathway. We used a murine model of NP caused by unilateral sciatic nerve cuffing (Cuff). PF was injected intraperitoneally once a day for a total of 14 days. Pain and depression-like behavior changes were evaluated via behavioral tests. Pathological changes in the hippocampus of mice were observed by H&E staining. The levels of proinflammatory cytokines in the hippocampus were detected using ELISA. Activated microglia were measured by immunohistochemical staining. The TLR4/NF-κB signaling pathway-associated protein expression in the hippocampus was detected by western blotting. We found that the PF could significantly alleviate Cuff-induced hyperalgesia and depressive behaviors, lessen the pathological damage to the hippocampal cell, reduce proinflammatory cytokines levels, and inhibit microglial over-activation. Furthermore, PF downregulated the expression levels of TLR4/NF-κB signaling pathway-related proteins in the hippocampus. These results indicate that PF is an effective drug for improving the comorbidity between NP and depression.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.247-247
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• 2017

Byobusan area of Aomori prefecture in Japan was a marshy sand dune and had developed for agricultural land use with a large-scale sprinkler system. Recently, it becomes an agricultural problem at this area that distinctive damage with browning maculation and fissures frequently occurs in Chinese yam tubers. Acetaldehyde is one of the factor candidates of underground part damage in plants. In this study, incidence rate of the tuber damage, and the morphological character and elemental composition of the damage parts in tubers were investigated with applications of excessive irrigation water or acetaldehyde water solution into the yam field. The incidence rate of the distinctive tuber damage increased as the input amount of irrigation water was increased. At the browning maculation parts of the tubers, many fissures and damages of cork layer were observed under scanning electron microscopy. In addition, the periderm of tubers was significantly thicker in damaged parts than in non-damaged parts. Funguses, bacterium and nematodes were not observed in the damaged part under scanning electron microscopy. The weight ratio of each constituent element in an analyzed area relative to the total weight of major essential elements was measured with energy dispersive X-ray spectrometry. The results showed that the weight ratios of boron, carbon, phosphorus, sulfur and calcium were higher in damaged parts than in non-damaged parts whereas the weight ratios of oxygen and chlorine were lower in damaged parts than in non-damaged parts. It was also shown by this spectrometry that iron, cadmium, lead and zinc were not directly involved in occurrence of the tuber damage. In this study, there was no remarkable difference of tuber appearance between non-acetaldehyde and acetaldehyde application treatments. From the above results, it is shown that the damage would be a physiological disorder induced by the input of a large quantity of water in the sandy field.

• Textile Coloration and Finishing
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• v.24 no.3
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• pp.213-220
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• 2012

In this study, we investigated the effect of natural vegetable treatment agent on the bleaching and damage of human hair during permanent wave formation. The vegetable treatment agent was prepared by fermenting the mixture of tea leaves (10g), black rice (100g), black bean (100g), corn (100g), malt (50g), and water(500g) at room temperature for 1 week. The degree of bleaching and damage was checked by Munsell value 'L' and morphological changes of hair in FE-SEM. When the hair was bleached, the Munsell value 'L' was almost same regardless of adding the vegetable treatment to the bleaching solution. But when the hair was permanently waved, the curl formation ability was high and the damage was low in the case of adding the vegetable treatment. This means that the vegetable treatment covers the scale of hair and protects the hair from the chemicals.

• Textile Coloration and Finishing
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• v.24 no.4
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• pp.305-312
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• 2012

In this study, we investigated the effects of oxidative permanent hair coloring agents on the dyeability and the damage of human hair. p-phenylenediamine and toluene-2.5-diamine sulfate were used as a hair coloring agent precursers. The degree of dyeability was checked by the change of CIELAB $L^*$ value according to dyeing time. And the damage of hair was evaluated by the tensile strength and morphological change of hair in SEM. When the hair was dyed, the CIELAB $L^*$ value was decreased with dyeing time regardless of the type of precursers. But when the hair was dyed after nutritional treatment, the CIELAB $L^*$ value showed lower level. This means that the nutritional treatment covers the scale of hair and protects the hair from the chemicals.

• Journal of Nutrition and Health
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• v.29 no.2
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• pp.159-165
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• 1996

This study was performed to investigate the effects of concentration and degree of unsaturation of fatty acids on cellular proliferation and lipid peroxide production, using primary skin fibroblasts from neonate rats Fibroblasts (CPD : 2.8-5.4). Cells were cultured either in control medium (Dulbecco's modified Eagle's medium supplement with 10% fetal bovine serum) or in media supplemented with various kinds (stearic, oleic, linoleic, arachidonic, linolenic, eicosapentaenoic acid) and amounts (5, 10, 25, 50, 100, 150uM)of fatty acids. Cellular proliferation ratio and lipid peroxice production were measured and morphological changes were observed. Cellular proliferation was inhibited and morphological changes were observed. Cellular proliferation was inhibited and morphological changes were observed in cells grown in stearic containing media. Oleic, arachidonic, and eicosapentaenoic aicd tend to stimulate cellualar proliferation, and linolenic acid had no effects. Lipid peroxide concentrations in fibroblasts increased in proportion to the contents and unsaturation of fatty acids in media. Especially supplementation of arachidonic acid accelerated cellualr lipid peroxidation. Free radicals may cause severs damage to biological molecules, so lipid peroxidation probably contributes cellular membrane damages. However there were little relationship between lipid peroxide production and cellular proliferation in this study. (Korean J Nutrition 29(2) : 159~165, 1996)