• Journal of Korea Foundry Society
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• v.35 no.6
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• pp.147-154
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• 2015

The effects of Sc and Sr elements on the modification of the eutectic $Mg_2Si$ phase and the castability were investigated in the Al-4wt%Mg-0.9wt%Si-0.3wt%Mn-0.15wt%Fe alloy. Measurements of the cooling curve and microstructure observations were performed to analyze the additional effects of Sc and Sr minor elements during the solidification process. A prominent effect found on the modification of the eutectic $Mg_2Si$ phase with additions of the Sr and Sc elements. Here, a fine eutectic $Mg_2Si$ phase and a decrease in the growth temperature of the eutectic $Mg_2Si$ phase were evident with an addition of Sc element up to 0.2 wt%. The growth temperature of the eutectic $Mg_2Si$ phase decreased and the effect on the modification of the eutectic $Mg_2Si$ phase increased with the addition of Sr element up to 0.02 wt%. The addition of 0.02wt%Sr had the strongest effect on the modification of the eutectic $Mg_2Si$ phase, and the resulting microstructure of the eutectic $Mg_2Si$ phase was found to have a fibrous morphology with a decreased aspect ratio and an increased modification ratio. Fluidity and shrinkage tests were conducted to evaluate the castability of the alloy. The addition of 0.02wt%Sr effectively increased the fluidity of the alloy, while an addition of Sc did not show any effect compared to when nothing was added. The maximum filling length was recorded for 0.01wt%TiB-0.02wt%Sr owing to the effect of the fine ${\alpha}$-Al grains. The macro-shrinkage ratio decreased, while the micro-shrinkage ratio increased with the addition of various eutectic modifiers. The highest ratio of micro-shrinkage was recorded for the 0.02wt%Sr condition. However, the total shrinkage ratio was nearly identical regardless of the amounts added in this study.

• Korean Journal of Clinical Pharmacy
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• v.8 no.2
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• pp.107-112
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• 1998

Lovastatin is a lipid lowering agent for the treatment of hypercholesterolemia and belongs to a new class of pharmacologic compounds called the 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase inhibitors. By competitively inhibiting HMG CoA reductase, lovastatin disrupts the biosynthesis of cholesterol in hepatic and peripheral cells and increases the synthesis of high-density-lipoprotein HDL) receptors. Following oral administration, the lactone ring of lovastatin is hydrolysed to the active inhibitor of HMG CoA reductase, lovastatin acid. Lovastatin is known to have poor oral absorption and wide individual variation. In this study, bioequivalence test of two lovastatin formulations, the test drug ($Lovaload^{TM}$, Chong Kun Dang Pharmaceutical Co.) and the reference drug ($Mevacor^{TM}$, Chung Wae Pharmaceutical Co.) were conducted according to the guidelines of Korea Food and Drug Administration (KFDA). A total of 18 healthy male volunteers, $31.90\pm3.60$ years old and $72.17\;7.88$ kg of body weight in average, were evaluated in a randomized crossover manner with a 2-week washout period. Concentrations of lovastatin acid in plasma were measured upto 12 hours following a single oral administration of eight tablets (20 mg of lovastatin per tablet) by high-performance liquid chromatography with UV detection at 238 nm. The area under the concentration-vs-time curve from 0 to 12 hours $(AUC_{0-12h})$ was calculated by the trapezoidal summation method. The statistical analysis showed that there are no significant differences in $AUC_{0-12h),\;C_{max}\;and\;T_{max}$ between the two formulations ($6.72\%,\;1.52\%,\;and\;0.88\$, respectively). The least significant differences between the formulations at $\alpha$=0.05 were less than $20\%\;(11.65\%,\;19.73\%,\;and\;14.81\%\;for\;AUC_{0-12h},\;C_{max}\;and\;T_{max}$, respectively). The $90\%$ confidence intervals for these parameters were also within $\pm20\%\;(-1.50{\leq}{\delta}{\leq}15.00$, $-12.50{\leq}{\delta}{\leq}15.50,\;and\;-9.64{\leq}{\delta]{\leq}11.40{\leq}\;for\;\;AUC_{0-12h}$ ,$C_{max}\;and\;T_{max}$, respectively). In conclusion, the new generic product $Lovaload^{TM}$ was proven to be bioequivalent with the reference drug.

• Korean Journal of Clinical Pharmacy
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• v.10 no.1
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• pp.13-18
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• 2000

The bioequivalence of two clarithromycin tablets, the $Klaricid^{TM}$ (Ciba-Geigy Korea Ltd.) and the $Pylocin^{TM}$ (Kyungdong Pharmaceutical Co., Ltd.), was evaluated according to the Korean Guidelines for Bioequivalence Test (KGBT 1998). Sixteen healthy male volunteers ($20\sim26$ years old) were randomly divided into two groups and a randomized $2\times2$ cross-over study was employed. After one tablet containing 250 mg of clarithromycin was orally administered, blood sample was taken at predetermined time intervals, and the concentrations of clarithromycin in serum were determined using high-performance liquid chromatographic method with electrochemical detector. The pharmaco-kinetic parameters (area under the concentration-time curve: $AUC_t$, maximum concentration; $C_{max}$ and time to maximum concentration; $T_{max}$) were calculated and analysis of variance (ANOVA) was utilized for the statistical analysis of parameters. The results showed that the differences in $AUC_t,\;C_{max}\;and\;T_{max}$ between two tablets based on $Klaricid^{TM}$ tablet were $-0.22\%,\;-0.48\%\;and\;-1.63\%$, respectively. The powers $(1-\beta)\;for\;AUC_t,\;C_{max}\;and\;T_{max}\;were\;99.07\%,\;88.15\%\;and\;99.99\%$, respectively. Detectable differences $(\Delta)\;and\;90\%$ confidence intervals ($\alpha$=0.10) were all less than $\pm20\%$ All the parameters above met the criteria of KGBT 1998, indicating that $Pylocin^{TM}$ tablet is bioequivalent to $Klaricid^{TM}$ tablet.

• Journal of Life Science
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• v.26 no.8
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• pp.921-927
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• 2016

Postprandial hyperglycemia is an early defect of type 2 diabetes and one of primary anti-diabetic targets. The alpha-glucosidase inhibitors regulate postprandial hyperglycemia by impeding the rate of carbohydrate (such as starch) digestion in the small intestine. This study was designed to investigate the inhibitory actions of mulberry fruit extract (MFE) on α-glucosidase and α-amylase activities, and its alleviating effect on postprandial hyperglycemia activities in vitro and in vivo. Male four-week old ICR mice and streptozotocin (STZ)-induced diabetic mice were treated with mulberry fruit extract. MFE showed strong inhibitory effects against α-glucosidase and α-amylase activities, with half-maximal inhibitory concentration (IC₅₀) values of 0.16 and 0.14 mg/ml, respectively, and was more effective than acarbose, which was used as a positive control. The increase in postprandial blood glucose levels was more significantly attenuated in the MFE-administered group mice than in the control group mice of both STZ-induced diabetic and normal mice. Moreover, the area under the glucose response curve significantly decreased following MFE administration in diabetic mice. These results indicate that MFE may be a potent inhibitor of α-glucosidase and α-amylase, and helpful in suppressing postprandial hyperglycemia in diabetic mice. The mulberry fruit extracts may be considered as a potential candidate for the management of diabetes.

• Journal of the Korean Data and Information Science Society
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• v.25 no.3
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• pp.567-578
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• 2014

PEAS (performance enhancement attitude scale) has been used to measure attitude and disposition toward doping in elite athlete. It is constructed of 17-item, 6-point scale. The purpose of this study was to verify validity of the PEAS for Korean elite player through Rasch model. The scale was administered to 438 Korean elite players. Principal component analysis was used to verify unidimensionality using SPSS program. Rasch measurement computer program, WISTEPS, was used to estimate goodness-of-fit of items and category structure. Differenctial item functioning by gender was also estimated by the WINSTEPS program. All alpha level was set at 0.05. First, principal component analysis showed that unidimensionality is satisfied as over 20.0% of variance of eigenvalue. Second, category probabilities curve showed 5-point scale was better than 6-point scaled statistically. Third, seven items (1, 9, 10, 12, 13, 14, 17) in the 17-item were not good model fit and three items (3, 12, 13) were estimated as the differential item functioning. This study showed that 9-item, 5-point scale is better PEAS to Korean elite player.

• Journal of The Korean Astronomical Society
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• v.55 no.4
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• pp.123-130
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• 2022

We present the analysis of a planetary microlensing event OGLE-2019-BLG-0362 with a shortduration anomaly (~0.4 days) near the peak of the light curve, which is caused by the resonant caustic. The event has a severe degeneracy with ∆𝜒² = 0.9 between the close and the wide binary lens models both with planet-host mass ratio q ≃ 0.007. We measure the angular Einstein radius but not the microlens parallax, and thus we perform a Bayesian analysis to estimate the physical parameters of the lens. We find that the OGLE-2019-BLG-0362L system is a super-Jovian-mass planet $M_p=3.26^{+0.83}_{-0.58}M_J $ orbiting an M dwarf $M_h=0.42^{+0.34}_{-0.23}M_{\odot}$ at a distance $D_L=5.83^{+1.04}_{-1.55}kpc$. The projected star-planet separation is ${\alpha}_{\bot}= 2.18^{+0.58}_{-0.72}AU$, which indicates that the planet lies beyond the snow line of the host star.

• Animal Bioscience
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• v.36 no.9
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• pp.1336-1349
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• 2023

Objective: The study was conducted to screen differentially expressed miRNAs in sows at early pregnancy by high-throughput sequencing and explore its mechanism of action on embryo implantation. Methods: The blood serum of pregnant and non-pregnant Landrace×Yorkshire sows were collected 14 days after artificial insemination, and exosomal miRNAs were purified for high throughput miRNA sequencing. The expression patterns of 10 differentially expressed (DE) miRNAs were validated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The qRT-PCR quantified the abundance of serum exosomal miR-192 in pregnant and control sows, and the diagnostic power was assessed by receiver operating characteristic (ROC) analysis. The target genes of DE miRNAs were predicted with bioinformatics software, and the functional and pathway enrichment analysis was performed on gene ontology and the Kyoto encyclopedia of genes and genomes terms. Furthermore, a luciferase reporter system was used to identify the target relation between miR-192 and integrin alpha 4 (ITGA4), a gene influencing embryo implantation in pigs. Finally, the expression levels of miRNAs and the target gene ITGA4 were analyzed by qRT-PCR, and western blot, with the proliferation of BeWo cells detected by cell counting kit-8 (CCK-8). Results: A total of 221 known miRNAs were detected in the libraries of the pregnant and non-pregnant sows, of which 55 were up-regulated and 67 were down-regulated in the pregnant individuals compared with the non-pregnant controls. From these, the expression patterns of 10 DE miRNAs were validated. The qRT-PCR analysis further confirmed a significantly higher expression of miR-192 in the serum exosomes extracted from pregnant sows, when compared to controls. The ROC analysis revealed that miR-192 provided excellent diagnostic accuracy for pregnancy (area under the ROC curve [AUC]=0.843; p>0.001). The dual-luciferase reporter assay indicated that miR-192 directly targeted ITGA4. The protein expression of ITGA4 was reduced in cells that overexpressed miR-192. Overexpression of miR-192 resulted in the decreased proliferation of BeWo cells and regulated the expression of cell cycle-related genes. Conclusion: Serum exosomal miR-192 could serve as a potential biomarker for early pregnancy in pigs. miR-192 targeted ITGA4 gene directly, and miR-192 can regulate cellular proliferation.

• Journal of Gastric Cancer
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• v.8 no.4
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• pp.232-236
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• 2008

Purpose: Laparoscopic surgery for gastric cancer was introduced in the past decade because it was considered less invasive than open surgery, and this results in less postoperative pain, faster recovery and an improved quality of life. Several studies have demonstrated the safety and feasibility of this procedure. We examined the outcome of performing laparoscopic surgery for gastric cancer over the last two year. Materials and Methods: From April 2004 to December 2006, 329 patients with gastric adenocarcinoma underwent a laparoscopy-assisted distal gastrectomy with lymph node dissection. The data was retrospectively reviewed in terms of the clinicopathologic findings, the perioperative outcomes and the complications. Results: The total patient group was comprised 196 men (59.6%) and 133 women (40.4%). The mean BMI was 23.6 and the mean tumor size was 2.7 cm. The mean number of harvested lymph node was 22.7, and this was 18.6 before 30 cases and 23.1 after 30 cases, and the difference was significant (P=0.02). The mean operation time was 180.9 min, and this was than 287.9 min before 30 cases and 170.2 min after 30 cases. After 30 cases, there was a significant improvement of the operation time (P<0.01). The mean incision length after 30 cases was shorter than that before 30 cases (P<0.01). Postoperative complications occurred in 24 (7.3%) of 329 patients and there was no conversion to open surgery. Conclusion: Even though the LADG was accompanied by a difficult learning curve, we successfully performed 329 LADG procedures over the past 2 years and we believe that LADG is a safe, feasible operation for treating most early gastric cancers (EGC).

• Journal of Life Science
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• v.15 no.5 s.72
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• pp.819-825
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• 2005

The Antioxidative accvities of the cell free extracts containing high glutathione by Saccharomyces cerevisiae FF-8 were tested in vitro experimental models : DPPH method for radical scavenging activity, ferric TBA method and ferric thiocyanate method using linoleic acid and tissue microsome for lipid peroxidation inhibitions. The concentration of intercellular glutathione by cultivating S. cerevisiae FF-8 in the YM optimal medium obtained $204\mug/ml$, which was increased by 2.76-fold from $74\mug/ml$ in the YM basal medium. A comparition between the YM basal medium and the YM optimal medium on antioxidative substance produced by S. cerevisiae FF-8 was investigated. In DPPH ($\alpha, \alpha-diphenyl-\beta-picrylhydrazyl$) method, the electron donating activity of the glutathione produced by S. cerevisiae FF-8 cultured in the YM optimal medium was as high as that of BHT ($ 0.05\%w/v $). The antioxidative a.tivity was measured by inhibition against lipid peroxidation of rat tissues' microsomes. The results of anti-oxidant activity of the cell free extracts by S. rerevisiae FF-8 cultured in the YM optimal medium was shown in the following order . $ liver 60.98\% > kidney 56.43\% > heart 52.91\% > brain 52.13\% > testis 45.57\% > spleen 42.95\% $. In antioxidative activities determined by ferric thiocyanate method and TBA methods against lipid peroxidation, the lipid peroxidation in the control mixture increased more rapidly than the typical peroxidation curve of linoleic acid from one day. The antioxidative activity of the cell free extracts by cultivating S. cerevisine FF-8 in the YM optimal medium were higher than that of the YM basal medium. These data indicate that the cell free extracts containing a high intercellular glutathione of S. cerevisiae FF-8 cultured in YM optimal medium showed strong antioxidative capacities by DPPH radical scavenging activity and ferric thiocyanate and TBARS measurements.

• Journal of Life Science
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• v.19 no.9
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• pp.1218-1225
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• 2009

Difractose anhydrides (DFAs) is studied as a sweetener for diabetics because of its structural property. DFAs have four types: DFA I, III, IV (degradation of levan) and V (degradation of inulin). Especially, DFA IV has been shown to enhance the absorption of calcium in experiments using rats. Levan fructotransferase is an enzyme for producing di-d-fructose-2,6':6,2-dianhydride (DFA IV). To identify structural characterization, we purified wild-type and mutants (D63A, D195N and N85S) of levan fructotransferase (LFTase) from Microbacterium sp. AL-210. These proteins were purified to apparent homogeneity by Ni-NTA affinity column, Q-sepharose ion exchange and gel filtration chromatography and detected by SDS-PAGE. They were also analyzed by circular dichroism (CD) measurements, JNET secondary structure prediction, activity measurements at various temperatures, and pH analysis. The optimum pH for the enzyme-catalyzed reaction was pH 7.5 and optimum temperature was observed at $55^{\circ}C$. Along with wild-type LFTase, mutants were analyzed by CD measurement, fluorescence analysis and differential scanning calorimetry (DSC). N85S showed less $\alpha$-helix and more $\beta$ strand than others. Also, N85S showed almost the same curve as wild-type in their steady-state fluorescence spectra, whereas mutant D63A and D195N showed higher intensity than wild-type. The amino acid sequence of wild-type LFTase was compared to the sequences of exo-inulinase from Aspergillus awamori, a plant fructan 1-exohydrolase from Cichorium intybus, and Thermotogo maritime (Tm) invertase and showed a high identity with Exo-inulinase from Aspergillus awamori.