• Tuberculosis and Respiratory Diseases
• /
• v.46 no.5
• /
• pp.636-644
• /
• 1999

Background : Tumor necrosis factor(TNF) has been considered as an important candidate for cancer gene therapy based on its potent anti-tumor activity. The mechanisms of TNF cytotoxicity are not clearly understood and some has reported that reactive oxygen species(ROS) might be associated with them, but there is controversy about antioxidant effect on TNF cytotoxicity. This study was designed to compare the TNF cytotoxicity after antioxidant pretreatment with that of control to evaluate the role of ROS in the mechanism of TNF cytotoxicity. Method : We compared the TNF cytotoxicies to WEHI164(murine fibrosarcoma cell line) and ME180(human cervix cancer cell line) after antioxidant pretreatment with those of control by MIT(dimethylthiazolyl-diphenyltetrazolium bromide) assay. Results : In the control group, the TNF cytotoxicities were $92.2{\pm}2.8%$(WEHI164) and $59.9{\pm}7.0%$(MEl80). In the TMTU(tetramethyl thiourea) pretreatment group, those were $91.4{\pm}3.7%$ and $74.6{\pm}7.0%$. In the PMZ(promethazine) pretreatment group, those were $90.2{\pm}2.5%$ and $62.5{\pm}5.7%$. In the BHT(butylated hydroxytoluene) pretreatment group, those were $93.2{\pm}1.3%$ and $66.3{\pm}6.1%$. So there was no reduction in TNF cytotoxicity after antioxidants pretreatment. Conclusion : The ROS may not have major role in the mechanisms of TNF cytotoxicity.

• 한국공간정보시스템학회:학술대회논문집
• /
• 2004.12a
• /
• pp.169-181
• /
• 2004

SK Telecom has already constructed GIMS system as the base common framework of LBS/GIS service system based on OGC(OpenGIS Consortium)'s international standard for the first mobile vector map service in 2002, But as service content appears more complex, renovation has been needed to satisfy multi-purpose, multi-function and maximum efficiency as requirements have been increased. This research is for preparation ion of GML3-based platform to upgrade service from GML2 based GIMS system. And with this, it will be possible for variety of application services to provide location and geographic data easily and freely. In GML 3.0, it has been selected animation, event handling, resource for style mapping, topology specification for 3D and telematics services for mobile LBS multimedia service. And the schema and transfer protocol has been developed and organized to optimize data transfer to MS(Mobile Stat ion) Upgrade to GML 3.0-based GIMS system has provided innovative framework in the view of not only construction but also service which has been implemented and applied to previous research and system. Also GIMS channel interface has been implemented to simplify access to GIMS system, and service component of GIMS internals, WFS and WMS, has gotten enhanded and expanded function.

• Journal of Life Science
• /
• v.26 no.6
• /
• pp.633-639
• /
• 2016

Biomaterials including polymer, metal, ceramic, and composite have been widely applied for medical uses as medical fibers, artificial blood vessels, artificial joints, implants, soft tissue, and plastic surgery materials owing to their physicochemical properties. However, the biocompatibility and toxicity for film- and plate-form biomaterials is difficult to measure in mammalian cells because there is no appropriate incubation system. To solve these problems, we developed a novel mammalian cell culture system consisting of a silicone ring, top panel, and bottom panel and we applied two polymer films (PF) and one metal plate (MP). This system was based on the principal of sandwiching a test sample between the top panel and the bottom panel. Following the assembly of the culture system, SK-MEL-2 cells were seeded onto Styela Clava Tunic (SCT)-PF, NaHCO₃-added SCT (SCTN)-PF, and magnesium MP (MMP) and incubated at 37℃ for 24 hr and 48 hr. An MTT assay revealed that cell viability was maintained at a normal level in the SCT-PF culture group at 24 or 48 hr, although it rapidly decreased in the SCTN-PF culture group at 48 hr. Furthermore, the cell viability in the MMP culture group was very similar to that of the control group after incubation for 24 hr and 48 hr. Together, these results suggest the sandwich-type mammalian culture system developed here has the potential for the evaluation of the biocompatibility and toxicity of cells against PF- and MP-form biomaterials.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 2007.11a
• /
• pp.79-92
• /
• 2007

Oxidative stress have known to be a risk factor for the degenerative processes and closely related to a lot of diseases. It is well established that antioxidants are good in protection and therapeutic means against oxidative damage. There is increasing interest in natural antioxidants and many natural antioxidants have been found and utilized as the possible protection for various diseases and skin aging. We have screened natural antioxidant agents for cosmeceuticals, nutraceuticals, and drugs as therapeutic and preventive means against oxidative stress, and have developed a number of novel antioxidants from various natural sources. A novel melanin synthesis inhibitor, Melanocin A, isolated from the metabolite of a fungal strain Eupenicillium shearii F80695 inhibited mushroom tyrosinase and melanin biosynthesis of B16 melanoma cells with $IC_{50}$ value of 9.0 nM and MIC value of $0.9\;{\mu}M$, respectively. Melanocin A also exhibited potent antioxidant activity by scavenging of DPPH and superoxide anion radicals. UV was found to increase the level of hydrogen peroxides and other reactive oxygen species (ROS) in skin tissues. This increase in ROS may not only alter the structure and function of many genes and proteins directly but may also modulate their expressions through signal transduction pathways and, ultimately, lead to skin damage. We investigated the effect of Melanocin A on UV-induced premature skin aging. Firstly, the effect of Melanocin A on UV-induced matrix metalloproteinase (MMP)-9 expression in an immortalized human keratinocyte cell line, HaCaT in vitro was investigated. Acute UV irradiation induced MMP-9 expression at both the mRNA and protein levels and Melanocin A suppressed this expression in a dose-dependent manner. We then investigated UV-induced skin changes in hairless mice in vivo by Melanocin A. Chronic exposure of hairless mouse dorsal skin to UV increased skin thickness and induced wrinkle formation and the gelatinase activities of MMP-2 and MMP-9. Moreover, Melanocin A significantly suppressed UV-induced morphologic skin changes and MMP-2 and MMP-9 expression. These results show that Melanocin A can prevent the harmful effects of UV that lead to skin aging. Therefore, we suggest that Melanocin A should be viewed as a potential therapeutic agent for preventing and/or treating premature skin aging. Terrein is a bioactive fungal metabolite isolated from Penicillium species. Terrein has a relatively simple structure and can be easily synthesized. However, the biologic effects of terrein are comparatively unknown. We found for the first time that terrein potently inhibit melanin production in melanocytes and has a strong hypopigmentary effect in a spontaneously immortalized mouse melanocyte cell line, Mel-Ab. Treatment of Mel-Ab cells with terrein (10-100 mM) for 4 days significantly reduced melanin levels in a dose-dependent manner. In addition, terrein at the same concentration also reduced tyrosinase activity. We then investigated whether terrein influences the extracellular signal-regulated protein kinase (ERK) pathway and the expression of microphthalmia-associated transcription factor (MITF), which is required for tyrosinase expression. Terrein was found to induce sustained ERK activation and MITF down-regulation, and luciferase assays showed that terrein inhibits MITF promoter activity in a dose-dependent manner. To elucidate the correlation between ERK pathway activation and a decreased MITF transcriptional level, PD98059, a specific inhibitor of the ERK pathway, was applied before terrain treatment and found to abrogate the terrein-induced MITF attenuation. Terrein also reduced the tyrosinase protein level for at least 72 h. These results suggest that terrain reduces melanin synthesis by reducing tyrosinase production via ERK activation, and that this is followed by MITF down-regulation.

• Journal of Digital Convergence
• /
• v.11 no.8
• /
• pp.251-263
• /
• 2013

To explore the device to allow the marriage immigrants' family to take jobs in our country, the social and economic environments that they face are investigated and analyzed through literature survey and field inquiry. The principal motive of the marriage to Korean is economic problem. But their actual economic conditions are inferior, and other legal problems, such as getting jobs and remitting money to their home country, drive them to unstable status. The present hiring policy is applied only to foreign workers with no domestic relations(E-9), hence the marriage immigrants are excluded from the domestic employment. To make institutional devices for giving them the employment opportunity, the modification of the existing laws are proposed. For examples, the 'Act on employment of foreign workers' can be revised to permit immigrant's relatives to get jobs, and 'Immigration control law' can be amended to guarantee legal qualification for taking jobs. It is desirable that the overall control be made by the Prime Minister's Office, and operation as well as surveillance be performed by the Ministry of Gender Equality and Family (MGEF) and the Ministry of Employment and Labor (MEL).

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.6
• /
• pp.679-686
• /
• 2020

In this thesis, an enhanced method for the feature extraction of vocal source signals and score combination using an MCE-Based weight estimation of the score of multiple feature vectors are proposed for the performance improvement of speaker recognition systems. The proposed feature vector is composed of perceptual linear predictive cepstral coefficients, skewness, and kurtosis extracted with lowpass filtered glottal flow signals to eliminate the flat spectrum region, which is a meaningless information section. The proposed feature was used to improve the conventional speaker recognition system utilizing the mel-frequency cepstral coefficients and the perceptual linear predictive cepstral coefficients extracted with the speech signals and Gaussian mixture models. In addition, to increase the reliability of the estimated scores, instead of estimating the weight using the probability distribution of the convectional score, the scores evaluated by the conventional vocal tract, and the proposed feature are fused by the MCE-Based score combination method to find the optimal speaker. The experimental results showed that the proposed feature vectors contained valid information to recognize the speaker. In addition, when speaker recognition is performed by combining the MCE-based multiple feature parameter scores, the recognition system outperformed the conventional one, particularly in low Gaussian mixture cases.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.42 no.11
• /
• pp.1744-1752
• /
• 2013

We investigated the protective effect of UVB inducing photodamage from mulberry extract (ME) and Lithospermum erythrorhizon extract (LE). The contents of total anthocyanin and shikonin as a color compound of ME and LE were 4.92 mg/g and 9.58 mg/g, respectively. The electron donating ability and superoxide radical scavenging activity of ME were 84.32% and 76.34%, respectively. The oxygen radical absorbance capacity of the ME ($545.37{\mu}moles$ TE/g) was higher than LE ($427.18{\mu}moles$ TE/g). MMP-1 production in the HS68 cells were exposed to UVB suppressed by treatment with $200{\mu}g/mL$ of ME (68.6%) and LE (32.7%). ME and LE were applied to a skin aging mouse model, which was induced by the irradiation of UVB to the backs of hairless mice. The value of skin erythema index, wrinkle depth and thickness, epidermis thickness, and collagenous fiber damage in the experiment groups (MEL: ME 3%, MEM: ME 5%, MEH: ME 7%, LEL: LE 3%, LEM: LE 5%, LEH: LE 7%) were remarkably reduced than in the control group (only UVB exposure group), while water capacity increased. The level of total wrinkles depth in the skin was decreased to be 30% of the control group by MEH and LEM. These results suggest that ME and LE are useful cosmetic materials for skin protection against UVB-inducing.

• Textile Coloration and Finishing
• /
• v.27 no.1
• /
• pp.70-79
• /
• 2015

To establish the optimal conditions for the manufacture of high absortive cellulose film(CF) originated from Styela clava tunic(SCT), the physicochemical properties included absorption was measured in CFs prepared under the various conditions. The highest absorption was observed for SCT-CF20 prepared from the cellulose solution dissolved at $80^{\circ}C$ for 20min, although the filtration treatment did not induce any significance alteration. Also, the absorption was higher in SCT-CF20-F prepared by the freeze drying than SCT-CF20-N(ambient air drying) and SCT-CF20-H(heat drying). The addition of porogen($NaHCO_3$) induced an increase of absorption in SCT-CF20-PF relative to SCT-CF20-F, while the number of interconnected porous structures was enhanced in SCT-CF20-PF. Furthermore, a high level of SK-MEL-2 cells viability was observed in SCT-CF20-PN and SCT-CF20-PF cultured group. These results show that SCT-CF may have high absorption and biocompatibility when prepared from SCT cellulose solution dissolved at $80^{\circ}C$ for 20min after addition of porogen and then subjected to freeze drying.

• The Journal of the Acoustical Society of Korea
• /
• v.23 no.2
• /
• pp.180-186
• /
• 2004

The presence of noise in speech signals degrades the performance of recognition systems in which there are mismatches between the training and test environments. To make a speech recognizer robust, it is necessary to compensate these mismatches. In this paper, we studied about an improvement of stochastic feature extraction based on band-SNR for robust speech recognition. At first, we proposed a modified version of the multi-band spectral subtraction (MSS) method which adjusts the subtraction level of noise spectrum according to band-SNR. In the proposed method referred as M-MSS, a noise normalization factor was newly introduced to finely control the over-estimation factor depending on the band-SNR. Also, we modified the architecture of the stochastic feature extraction (SFE) method. We could get a better performance when the spectral subtraction was applied in the power spectrum domain than in the mel-scale domain. This method is denoted as M-SFE. Last, we applied the M-MSS method to the modified stochastic feature extraction structure, which is denoted as the MMSS-MSFE method. The proposed methods were evaluated on isolated word recognition under various noise environments. The average error rates of the M-MSS, M-SFE, and MMSS-MSFE methods over the ordinary spectral subtraction (SS) method were reduced by 18.6%, 15.1%, and 33.9%, respectively. From these results, we can conclude that the proposed methods provide good candidates for robust feature extraction in the noisy speech recognition.

• The Korea Journal of Herbology
• /
• v.21 no.2
• /
• pp.151-158
• /
• 2006

Objectives : The purpose of the present study is to observe the neuroprotective effect of the $NeuBo153^{\circledR}$ on transient focal cerebral ischemia in rats. Methods : $NeuBo153^{\circledR}$ was made by mixing the herbs, mainly the root of Panax ginseng, the root of Rehmannia glutinosa and Poria cocos, the stem bark of Acanthopanax senticosus, the root of Scutellaria baicalensis and Mel, and heating for 96 hours. Transient Focal cerebral ischemia (2 h of ischemia, 22 h of reperfusion) was induced by intraluminal suture method with SD rats. Sensory motor function was tested by rotarod test, prehensile traction test, beam balance test and foot fault test at 24 h after ischemia. The brain slices were stained by 2% 2, 3, 5-triphenyltetrazolium chloride and the infarct volume was measured by graphic analyzer at 24 h after ischemia. Results : $NeuBo153^{\circledR}$ treated group did not show significant differences compared with vehicle treated group in body temperature. Oral administration of $NeuBo153^{\circledR}$ reduced brain infarct volume by 29.7% compared with vehicle treated group. $NeuBo153^{\circledR}$ also showed protective effects on sensory motor functional deficits. Conclusion : $NeuBo153^{\circledR}$ treatment reduced brain damage and improved functional deficits induced by MCAo. It showed neuroprotective effects even when treatment was relayed 2 h after injury. Further research is required to evaluating long term functional recovery am accurate therapeutic range and mechanisms.