• Korean Journal of Human Ecology
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• v.12 no.2
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• pp.253-263
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• 2003

The purposes of this study were to find out an evaluation scale that could predict wear comfort and to investigate the effect of the skin-contacting fiber type on the subjective sensation and microclimate. Sensorial evaluation was basically followed by the Human Perception Analysis (HPA) interviewing 144 consumers. Sixteen female subjects were participated in the sleeve wear test with and without wearing vapor permeable water repellent outerwear. Experimental sleeves were constructed using the same double knit by turning inside out to control other material effects except the skin-contacting fiber type, hence each different side of double knit, cotton side and the cotton/polypropylene blend side, was next to skin in each trial of the experiment. As results, it was noted that the term representing a combined feeling of thermal and wetness sensation, and muggy appeared to be a powerful language to measure perceptual responses of human subject among five dimensions of evaluation. although the ordinary users did not use the term very often. As for the comfort properties of double knits, it seemed that subjects slightly more preferred polypropylene/cotton blend to cotton as the skin-contacting fiber type when they wore outerwear and their skin were covered with sweat, although the result was rot statistically significant and need to be confirmed under higher work load.

• Journal of Society of Preventive Korean Medicine
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• v.12 no.3
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• pp.47-58
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• 2008

The anticancer and antioxidant effect of different lengths of saturated fatty acids was tested on NIH3T3 fibroblasts and human skin melanoma cellsn in this study. The cell existence rate and antioxidizing capacity and optic reservation of cells were observed. This saturated fatty acid was concentration-dependent. IC50 Concentrations in NIH3T3 fibroblasts, human skin melanoma cells and DPPH radical scavenging activity of fatty acid was increasing the order of carbochain length ; caprylic acid < lauric acid < palmitic acid < stearic acid. The reduction in cell number and morphological change in human skin melanoma cells was increasing the order of carbochain length ; caprylic acid < lauric acid < palmitic acid < stearic acid. These results suggest that carbochain length of fatty acid can be used as structure-activity relationships for anticancer and antioxidant.

• Toxicological Research
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• v.26 no.1
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• pp.9-14
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• 2010

The evaluation of eye and skin irritation potential is essential to ensuring the safety of human in contact with a wide variety of substances. Despite this importance of irritation test, little is known with respect to the irritation potency of lomefloxacin, a fluoroquinolone antibiotic, which has been known to cause phototoxicity with an abnormal reaction of the skin. Thus, to investigate the tendency of lomefloxacin to cause eye and skin irritation, we carried out in vitro eye irritation test using Balb/c 3T3, and in vitro skin irritation test using $KeraSkin^{TM}$ human skin model system. 3T3 neutral red uptake assay has been proposed as a potential replacement alternative for the Draize Eye irritation test. In this study, the $IC_{50}$ value obtained for lomefloxacin was 375 ${\mu}g$. According to the classification model used for determining in vitro categories, lomefloxacin was classified as moderately irritant. For evaluation of skin irritation, engineered epidermal equivalents ($KeraSkin^{TM}$) were subjected to 10 and 25 mg of lomefloxacin for 15 minutes. Tissue damage was assessed by tissue viability evaluation, and by the release of a pro-inflammatory mediator, interleukin- 1${\alpha}$. Lomefloxacin increased the interleukin-1${\alpha}$ release after 15 minutes of exposure and 42 hours of post incubation, although no decrease in viability was observed. Therefore, lomefloxacin is considered to be moderately irritant to skin and eye.

• Clinical and Experimental Reproductive Medicine
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• v.32 no.2
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• pp.133-147
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• 2005

Objectives: This study was carried out to establish human embryonic stem cells derived from frozen-thawed embryos using mouse embryonic fibroblasts (mEFs), human fetal skin and muscle fibroblasts as feeder cells, and to identify the characteristic of embryonic stem cells. Methods: When primary mEFs, human fetal skin and muscle fibroblasts were prepared, passaging on 4 days from replating could have effective trypsinization and clear feeder layers. Eight of 23 frozenthawed 4~8 cell stage embryos donated from consenting couples developed to blastocysts. Inner cell mass (ICM) was isolated by immunosurgery. ICM was co-cultured on mEFs, human fetal skin or muscle fibroblasts. The ICM colonies grown on mEFs, human fetal skin or muscle fibroblasts were tested the expression of stage specific embryonic antigen-3, -4 (SSEA-3, -4), octamer binding transcription factor-4 mRNA (Oct-4) and alkaline phosphatase surface marker. Results: We obtained 1 ICM colony from 2 ICM co-cultured on mEFs as feeder cells and did not obtain any ICM colony from 6 ICM clumps co-cultured on human fetal skin or muscle fibroblasts. The colony formed on mEFs could be passaged 30 times every 5 days with sustaining undifferentiated colony appearance. When the colonies cultured on mEFs were grown on human fetal skin or muscle fibroblasts, the colonies could be passaged 15 times every 9 days with sustaining undifferentiated colony appearance. The colonies grown on mEFs and human fetal fibroblasts expressed SSEA-4 and alkaline phosphatase surface markers and positive for the expression of Oct-4 by reverse transcription-polymerase chain reaction (RT-PCR). The produced embryoid body differentiated spontaneously to neural progenitorlike cells, neuron-like cells and beating cardiomyocyte-like cells, and frozen-thawed embryonic stem cells displayed normal 46,XX karyotype. Conclusions: The human embryonic stem cells can be established by using mEFs and human fetal fibroblasts produced in laboratory as feeder cells.

• IMMUNE NETWORK
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• v.11 no.5
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• pp.227-244
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• 2011

MicroRNAs (miRNAs) are small noncoding RNA molecules that negatively regulate gene expression via degradation or translational repression of their target messenger RNAs (mRNAs). Recent studies have clearly demonstrated that miRNAs play critical roles in several biologic processes, including cell cycle, differentiation, cell development, cell growth, and apoptosis and that miRNAs are highly expressed in regulatory T (Treg) cells and a wide range of miRNAs are involved in the regulation of immunity and in the prevention of autoimmunity. It has been increasingly reported that miRNAs are associated with various human diseases like autoimmune disease, skin disease, neurological disease and psychiatric disease. Recently, the identification of miRNAs in skin has added a new dimension in the regulatory network and attracted significant interest in this novel layer of gene regulation. Although miRNA research in the field of dermatology is still relatively new, miRNAs have been the subject of much dermatological interest in skin morphogenesis and in regulating angiogenesis. In addition, miRNAs are moving rapidly center stage as key regulators of neuronal development and function in addition to important contributions to neurodegenerative disorder. Moreover, there is now compelling evidence that dysregulation of miRNA networks is implicated in the development and onset of human neruodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, Tourette's syndrome, Down syndrome, depression and schizophrenia. In this review, I briefly summarize the current studies about the roles of miRNAs in various autoimmune diseases, skin diseases, psychoneurological disorders and mental stress.

• Korean Journal of Pharmacognosy
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• v.39 no.4
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• pp.300-304
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• 2008

The root of Astragalus membranaceus Bunge (Leguminosae) has been used in the Korean oriental medicine for strengthening the vital energy. UV irradiation has been suggested as a major cause of photo aging in skin. In order to investigate protective effects against UV induced cellular damage, Astragali Radix was extracted with 70% ethanol and dissolved in DMSO. The protective effect was detected by MTT assay, LDH assay, and Comet assay in immortalized human keratinocyte cell line, HaCaT cell system after UV irradiation. Astragli Radix 70% EtOH extract reduced UV induced cellular damage in cell survival, membrane integrity and DNA damage.

• Korean Journal of Human Ecology
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• v.23 no.6
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• pp.1205-1215
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• 2014

The purpose of this study was to investigate the effect of local heating and cooling of various body parts on the skin temperature of the exposed extremities including neck. Hot pack was used to warm up the body of seven participants for 15 minutes and it was removed as the temperature of the hot pack decreased after 15minutes of warming. Thermograms of body surface with and without hot pack were analyzed intensively to observe the efficiency of the local heating of shoulder, abdomen, back waist, and foot on the skin temperature of ten area of the subjects' body. The results indicated that the absolute skin temperature of front upper arm and thigh was significantly higher depending on the area of heating, especially, in case of abdomen and foot heating, which was not observed at the back of the body. The rate of skin temperature of extremities such as finger, palm and foot was significantly different depending on the body area of local heating. Generally, it was found that back waist heating was not efficient to warm up and maintain the skin temperature of the body after removing the hot pack.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.3
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• pp.63-90
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• 2002

Quantitative measurement of melanin is the best method to evaluate whitening effect of cosmetics on human skin. However, non-invasive method to quantify human skin melanin with high precision has not been established. Whitening effect of cosmetics on the skin results in lightening of skin color. Therefore, it is reasonable to measure skin color in a reproducible manner for the assessment of whitening effect. Several Instruments or methods, such as colorimeter, mexameter, and visual assessments by experts , have been used for this purpose. In this lecture I will review the details of various assessment methods for the evaluation of whitening effect and discuss the pros and cons of each method. Then I will present briefly the results of clinical trial. Finally I will introduce new non-invasive modalities to quantify melanocytes.

• International Journal of CAD/CAM
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• v.3 no.1_2
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• pp.61-66
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• 2003

This paper describes a novel experiment that measures skin movement with respect to the flexional motion of a hand. The study was based on MR images in conjunction with CAD techniques. The MR images of the hand were captured in 3 different postures with surface markers. The surface markers attached to the skin where employed to trace skin movement during the flexional motion of the hand. After reconstructing 3D isosurfaces from the segmented MR images, the global registration was applied to the 3D models based on the particular bone shape of different postures. Skin movement was interpreted by measuring the centers of the surface markers in the registered models.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.277.2-277.2
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• 2014

For next-generation electronic applications, human-machine interface devices have recently been demonstrated such as the wearable computer as well as the electronic skin (e-skin). For integration of those systems, it is essential to develop many kinds of components including displays, energy generators and sensors. In particular, flexible sensing devices to detect some stimuli like strain, pressure, light, temperature, gase and humidity have been investigated for last few decades. Among many condidates, a pressure sensing device based on organic field-effect transistors (OFETs) is one of interesting structure in flexible touch displays, bio-monitoring and e-skin because of their flexibility. In this study, we have investigated a flexible e-skin based on highly sensitive, pressure-responsive OFETs using microstructured ferroelectric gate dielectrics, which simulates both rapidly adapting (RA) and slowly adatping (SA) mechanoreceptors in human skin. In SA-type static pressure, furthermore, we also demonstrate that the FET array can detect thermal stimuli for thermoreception through decoupling of the input signals from simultaneously applied pressure. The microstructured highly crystalline poly(vinylidene fluoride-trifluoroethylene) possessing piezoelectric-pyroelectric properties in OFETs allowed monitoring RA- and SA-mode responses in dyanamic and static pressurizing conditions, which enables to apply the e-skin to bio-monitoring of human and robotics.