• Development and Reproduction
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• v.22 no.3
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• pp.235-244
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• 2018

We investigate the effect of endoplasmic reticulum (ER) stress inhibitor treatment during parthenogenetic activation of oocytes on the ER stress generation, apoptosis, and in vitro development of parthenogenetic porcine embryos. Porcine in vitro matured oocytes were activated by 1) electric stimulus (E) or 2) $E+10{\mu}M$ Ca-ionophore (A23187) treatment (EC). Oocytes were then treated by ER stress inhibitors such as salubrinal (200 nM) and tauroursodeoxychloic acid (TUDCA, $100{\mu}M$) for 3 h prior to in vitro culture. Parthenogenetic embryos were sampled to analyze ER stress and apoptosis at the 1-cell and blastocyst stages. The x-box binding protein 1 (Xbp1) mRNA and ER stress-associated genes were analyzed by RT-PCR or RT-qPCR. Apoptotic gene expression was analyzed by RT-PCR. At the 1-cell stage, although no difference was observed in Xbp1 splicing among treatments, BiP transcription level in the E group was significantly reduced by salubrinal treatment, and GRP94 and ATF4 transcription levels in EC group were significantly reduced by all treatments (p<0.05) compared to control. In the EC group, both apoptotic genes were reduced by ER stress inhibitor treatments compared to control (p<0.05) except Caspase-3 gene by TUDCA treatment. These results suggest that the treatment of ER stress inhibitor during parthenogenetic activation can reduce ER stress, and thereby reduce apoptosis and promote in vitro development of porcine parthenogenetic embryos.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.3
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• pp.233-240
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• 2020

Autophagy regulators are often effective as potential cancer therapeutic agents. Here, we investigated paclitaxel sensitivity in cells with knockout (KO) of ATG5 gene. The ATG5 KO in multidrug resistant v-Ha-ras-transformed NIH 3T3 cells (Ras-NIH 3T3/Mdr) was generated using the CRISPR/Cas9 technology. The qPCR and LC3 immunoblot confirmed knockout of the gene and protein of ATG5, respectively. The ATG5 KO restored the sensitivity of Ras-NIH 3T3/Mdr cells to paclitaxel. Interestingly, ATG5 overexpression restored autophagy function in ATG5 KO cells, but failed to rescue paclitaxel resistance. These results raise the possibility that low level of resistance to paclitaxel in ATG5 KO cells may be related to other roles of ATG5 independent of its function in autophagy. The ATG5 KO significantly induced a G₂/M arrest in cell cycle progression. Additionally, ATG5 KO caused necrosis of a high proportion of cells after paclitaxel treatment. These data suggest that the difference in sensitivity to paclitaxel between ATG5 KO and their parental MDR cells may result from the disparity in the proportions of necrotic cells in both populations. Thus, our results demonstrate that the ATG5 KO in paclitaxel resistant cells leads to a marked G₂/M arrest and sensitizes cells to paclitaxel-induced necrosis.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.1011-1017
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• 2001

Streptomyces sp. Y-110 cytochrome P-450, induced by the addition of compactin -Na into the culture medium, was purified from the cell extract to apparent homogeniety, mainly by DEAE-Sepharose, hydroxyapatite, and Mono Q column chromatyography. The sepcific activity of purified enzyme on its substrate, compactin-Na, was determined to be 15 nmol of pravastatin per mg protein. The molecular mass of this enzyme on SDS-PAGE was $37{\pm}0.5$ kDa, pI was 4.5, and its CO difference spectrum showed maximum absorption peaks at 452 and 550nm, respectively. The N-terminal amino acid sequence was determined to be Met>Thr>Cys>Thr>Pro>Val>Thr>Val>The>Gly>Ala>Ala>Gly>Gln>Ile>Gly>Tyr>Ala>Leu. Its apparent $K_m$ on compactin-Na was $1.294{\mu}M{\cdot}min^-1,\;and\;V_{max}\;was\;1.028{\mu}M{\cdot}min^-1$. The maximum substrate concentration ($K_s$) for reaction was $270 {\mu}M$and thus $1/[K_s]$ was $3.7{\mu}M$. These physicochemical characteristics and kinetic behavior of this enzyme were compared and shown to be different from those of Streptomyces cytochrome P-450 enzymes reported, suggesting that this enzyme may be an additional member of the Streptomyces cytochrome P-450 family.

• Journal of the Korean Society for Marine Environment & Energy
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• v.3 no.2
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• pp.11-17
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• 2000

The drift and movement of oil slick in the sea are closely related to the flows at the sea surface (at 0m depth) because specific gravity of an oil is lighter than that of sea water. As an effort toward a development of realistic model for oil spill drift on the sea surface, a study on sea surface wind-induced drift (skin drift) at 4 coastal regions of Korea was carried out. In this study, skin drifts were inferred from difference between the flow at the sea surface and that in underwater (at 1.5m depth). The average speed of skin drift in our experiments was 2.9% of wind speeds and the average direction of skin drift to wind was deflected to the right by 18.6°. The results of this experiment were used in the modelling of the skin drift as a prompt response of time-variable wind. The modelled skin drift, which corresponds to observed wind, successfully reproduced the observed trajectories of sea surface flows.

• The Korean Journal of Pain
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• v.30 no.4
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• pp.250-257
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• 2017

Vitamin D is a cofactor responsible for autoimmune disorders. There is no agreement in the studies investigating the association between vitamin D and fibromyalgia. This study aims to combine the conflicting results of the primary studies which compared these patients with control groups regarding the serum concentration of vitamin D. This meta-analysis has been designed based on PRISMA guidelines. Relevant keywords were searched in PubMed, Science direct, Scopus, Cochrane, and Google scholar and primary studies were selected. After screening the eligible studies according to inclusion/exclusion criteria, we investigated the risk of bias in the selected studies and also the heterogeneity between the primary results using Cochrane (Q) and I-squared ($I^2$) indices. The primary results were combined using inverse variance method and Cohen statistics as well as a random effects model. Publication bias was assessed using Egger test. Sensitivity analysis was applied to investigate the influence of each primary study on the final result of the meta-analysis. Suspected factors in the heterogeneity were assessed using meta-regression models. We entered 12 eligible studies in the meta-analysis including 851 cases compared with 862 controls. The standardized mean difference of Vitamin D between the two groups was -0.56 (95% confidence interval: -1.05, -0.08). Our meta-analysis showed that vitamin D serum levels of patients with fibromyalgia was significantly lower than that of control group.

• The Journal of the Korea Contents Association
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• v.9 no.5
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• pp.314-321
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• 2009

The main purpose of this paper is to examine the relationship between employment relations characteristic and job involvement according to employment type in hotel corporations. Using data from 238 employees from hotel corporations, this research shows the results in the below. First, there is a significant difference in the employment relations characteristic(employment security and peer relationships) and job involvement. Second, the employment type does not moderates the relationships between employment relations characteristic and job involvement. Third, employment security and peer relationships are powerful factors to predict job involvement in both form of worker.

• Journal of Oral Medicine and Pain
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• v.39 no.2
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• pp.63-68
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• 2014

Purpose: This study was designed to evaluate the sex and age differences in the Korean oral malodor patients. Methods: Subjects were the patients with oral malodor (male, 2,239; female, 3,496) visited the Department of Oral Medicine, Kyung Hee University Dental Hospital from January 2007 to December 2012 were recruited to this study and measured the volatile sulfur compounds (VSCs) in the oral cavity with Halimeter. Results: There were slightly more female than male (female : male=3 : 2), and the mean values of Halimeter result were 65.79 ppb (female) and 79.94 ppb (male), which was more higher in male. Total patients showed normal age distribution in both gender, and the peak was the age of 26-35 in female, the age of 36-45 in male. The percentages of pseudo-halitosis were 74.7% in female and 69.3% in male, which was more higher in female. Conclusions: Therefore, it was revealed that women are more likely to have oral malodor than men, and there was a difference in the largest age group between men and women. Also women had more pseudo-halitosis patient than men.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.4
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• pp.551-561
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• 1998

This paper was studied to understand the characteristics of heat transfer coefficients and surface temperature distributions around a circular combustion chamber within the heat-intercept duct of kerosene fan heater. The experiment was carried out in the heat-intercept duct of kerosene fan heater attached to the blow-down-type subsonic wind tunnel with a test section of 240 mm * 240 mm * 1200 mm. The purpose of this paper was to obtain the basic data related with normal combustion for new design from conventional kerosene fan heater, and to investigate the effect of surface temperature, local and mean heat transfer coefficients versus flow-rate of convection axial fan according to the variations of heat release conditions from kerosene fan heater during normal combustion. Consequently it was found that (i) the revolution of convection axial fan during combustion had a smaller value than that of non-combustion because of the thermal resistance due to the high temperature in the heat-intercept duct, (ii) the pressure ratio P$_{2}$/P$_{1}$ had a comparatively constant value of 0.844 according to the revolution increase of turbo fan and the heating performance of kerosene fan heater had a range of 1,494 ~ 3,852 kcal/hr, (iii) the local heat transfer coefficient around a circular combustion chamber had a comparatively larger scale in the range of 315 deg. < .theta. < 45 deg. than that in the range of 90 deg. < .theta. < 270 deg. as a result of heat transfer difference between front and back of a circular combustion chamber, and (iv) the mean heat transfer coefficient around a circular combustion chamber increased linearly like a H$_{m}$=95.196Q+104.019 in condition of high heat release according to the increase of flow-rate of axial fan.n.

• Archives of Plastic Surgery
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• v.38 no.1
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• pp.1-6
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• 2011

Purpose: Currently, soft tissue filler products based on hyaluronic acid are widely used. They are safe, effective, and convenient to use compared with bovine collagens. However, all commercially available hyaluronic acid based fillers in Korea are imported ones. The purpose of this study is to evaluate efficacy of a new hyaluronic acid filler (HyaFilia; CHA bio&Diostech Co., Seoul), which has been recently developed in Korea. Methods: Three kinds of soft tissue fillers, including Restylane (Q-Med, Uppsala, Sweden), HyaFilia (CHA bio & Diostech Co., Seoul), Juvederm (Allergan, CA, USA), were injected subdermally into the back of hairless mice at six sites. The 2 cephalic sites composed Restylane groups, the 2 middle sites HyaFilia groups, and the 2 caudal sites Juvederm groups. Six hairless mice were included in the study, therefore, a total of 12 injections per group were performed. After 16 weeks after injection, the nodular swellings that resulted from the injections were excised wide enough to include skin beyond the swelling points down to the panniculus carnosus layer using 8mm punches. Volumes and weights were measured using a stereoimage optical topometer system and a weighting machine. Histologic comparisons were also carried out. Results: The mean volumes of the Restylane, HyaFilia and Juvederm groups were $3698{\times}103$, $4820{\times}103$, and $1435{\times}103$ PI, respectively. The mean weights of the Restylane, HyaFilia and Juvederm groups were 36.08, 37.83, and 24.66 mg, respectively. Histologic examination between the 3 groups showed no significant difference in tissue compositions and inflammatory reactions. Conclusion: The results of this study shows that HyaFilia is superior to Restylane and Juvederm in longavity of filling effect. Therefore, HyaFilia may be an effective replacement for the imported materials including Restylane and Juvederm.

• Smart Structures and Systems
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• v.25 no.5
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• pp.605-617
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• 2020

The existence of damages in structures causes changes in the physical properties by reducing the modal parameters. In this paper, we develop a two-stages approach based on normalized Modal Strain Energy Damage Indicator (nMSEDI) for quick applications to predict the location of damage. A two-dimensional IsoGeometric Analysis (2D-IGA), Machine Learning Algorithm (MLA) and optimization techniques are combined to create a new tool. In the first stage, we introduce a modified damage identification technique based on frequencies using nMSEDI to locate the potential of damaged elements. In the second stage, after eliminating the healthy elements, the damage index values from nMSEDI are considered as input in the damage quantification algorithm. The hybrid of Teaching-Learning-Based Optimization (TLBO) with Artificial Neural Network (ANN) and Particle Swarm Optimization (PSO) are used along with nMSEDI. The objective of TLBO is to estimate the parameters of PSO-ANN to find a good training based on actual damage and estimated damage. The IGA model is updated using experimental results based on stiffness and mass matrix using the difference between calculated and measured frequencies as objective function. The feasibility and efficiency of nMSEDI-PSO-ANN after finding the best parameters by TLBO are demonstrated through the comparison with nMSEDI-IGA for different scenarios. The result of the analyses indicates that the proposed approach can be used to determine correctly the severity of damage in beam structures.