Interfacial Tension and Contact Angle Variations of SUS304 Melt in Contact with Solid Oxides and CaO - SiO2 - Al2O3 (CaF2) Slags at 1470℃

Kim, Dong Sik,SEO, Sung Mo,PAIK, Young Hyun,LEE, Won Pyo 대한금속재료학회(대한금속학회) 1996 METALS AND MATERIALS International Vol.2 No.2

Study on the interfacial properties of SUS304 melt in contact with pedestal oxides and also liquid slugs of varying chemistry was carried out by using a combination of the sessile drop method and a X-ray fluoroscopic technique at 1470℃. Interfacial tension and contact angle were obtained directly from a numerical solution of the Young-Laplace equation. Surface tension of SUS304 was found to be 1467 mN/m in Ar-atmosphere which was considerably lower than that of pure iron. This may be due to the existence of surface active elements such as Cr, Ni and Mn etc. in SUS304. Interfacial tensions of SUS304 in contact with CaO-SiO₂-Al₂O₃(CaF₂) slugs were in the range of 925 to 1148 mN/m. The contact angle between SUS304 and various pedestal was about 120° regardless of pedestal oxides, Al₂O₃, TiO₂ and SiO₂. Contact angles between SUS304 and the pedestal alumina coexisting with liquid CaO-SiO₂-Al₂O₃(CaF₂) were in the range of 125° to 142°.

The Influence of the Nucleotide Sequences of Random Shine-Dalgarno and Spacer Region on Bovine Growth Hormone Gene Expression

Paik Soon-Young,Ra Kyung Soo,Cho Hoon Sik,Koo Kwang Bon,Baik Hyung Suk,Lee Myung Chul,Yun Jong Won,Choi Jang Won The Microbiological Society of Korea 2006 The journal of microbiology Vol.44 No.1

To investigate the effects of the nucleotide sequences in Shine-Dalgarno (SD) and the spacer region (SD-ATG) on bovine growth hormone (bGH) gene expression, the expression vectors under the control of the T7 promoter (pT7-7 vector) were constructed using bGH derivatives (bGH1 & bGH14) which have different 5'-coding regions and were induced in E. coli BL21 (DE3). Oligonucleotides containing random SD sequences and a spacer region were chemically synthesized and the distance between the SD region and the initiation codon were fixed to nine bases in length. The oligonucleotides were annealed and fused to the bGH1 and bGH14 cDNA, respectively. When the bGH gene was induced with IPTG in E. coli BL21(DE3), some clones containing only bGH14 cDNA produced considerable levels of bGH in the range of $6.9\%\;to\;8.5\%$ of total cell proteins by SDS-PAGE and Western blot. Otherwise, the bGH was not detected in any clones with bGH1 cDNA. Accordingly, the nucleotide sequences of SD and the spacer region affect on bGH expression indicates that the sequences sufficiently destabilize the mRNA secondary structure of the bGH14 gene. When the free energy was calculated from the transcription initiation site to the +51 nucleotide of bGH cDNA using a program of nucleic acid folding and hybridization prediction, the constructs with values below -26.3 kcal/mole (toward minus direction) were not expressed. The constructs with the original sequence of bGH cDNA also did not show any expression, regardless of the free energy values. Thus, the disruption of the mRNA secondary structure may be a major factor regulating bGH expression in the translation initiation process. Accordingly, the first stem-loop among two secondary structures present in the 5'-end region of the bGH gene should be disrupted for the effective expression of bGH.

Induction of Differentiation of the Cultured Rat Mammary Epithelial Cells by Triterpene Acids

Paik, Kee-Joo,Jeon, Seong-Sill,Chung, Hae-Young,Lee, Kyung-Hee,Kim, Kyu-Won,Chung, Joon-Ki,Kim, Nam-Deuk The Pharmaceutical Society of Korea 1998 Archives of Pharmacal Research Vol.21 No.4

We investigated the effects of triterpene acids (TAs), ursolic acid (UA) and oleanolic acid (OA), on the induction of proliferation and differentiation of normal rat mammary epithelial cells (RMEC) or organoids cultured in Matrigel or primary culture system. To elucidate the effects, we tested their differentiation inducing activities with intercellular communication ability, cell cycle patterns, induction of apoptosis, and morphological differentiation in the three dimensional extracellular culture system. To study the changes of RMEC subpopulation in culture, the cultured cells were isolated, immunostained with peanut lectin (PNA) and anti-Thy-1.1 antibody and then analyzed with flow cytometry. Four different subpopulations, such as PNA and Thy-1.1 negative cells (B-), PNA positive cells (PNA+), Thy-1.1 positive cells (Thy-1.1+), PNA and Thy-1.1 positive cells (B+), were obtained and the size of each subpopulation was changed in culture with time in the presence of TAs. Intercellular communication was observed in culture for 7 days in TAs-treated cells, but not in culture for 4 days with scrape-loading dye transfer technique. $G_2$/M phase cells and the number of apoptotic population were increased in TAs-treated groups in cell cycle analyses. S phase fractions were reduced and the change of $G_1$ phase cells was not observed. The colonies with distinct multicelfular structures, such as stellate, ductal, webbed, squamous, lobulo-ductal colonies, were observed in Matrigel culture and the frequencies of each colony were changed in the presence of TAs. These results suggest that UA and OA have differentiation inducing effects on rat mammary epithelial cells in primary or in Matrigel culture.

Purification and Characterization of Complement-activating Acidic Polysaccharides from the Fruits of Capsicum annuum

Paik, Soon-Young,Ra, Kyung-Soo,Chang, In-Seop,Park, Yoon-Chang,Park, Hee-Sung,Baik, Hyung-Suk,Yun, Jong-Won,Choi, Jang-Won Korean Society for Biochemistry and Molecular Biol 2003 Journal of biochemistry and molecular biology Vol.36 No.2

Hot water-soluble crude polysaccharide (HCAP-0) that was obtained from the fruits of Capsicum annuum showed potent anti-complementary activity. The activity was unchanged by pronase digestion, but decreased by periodate oxidation. The HCAP-0 was fractionated by DEAE ion-exchange chromatography to give two major fractions, HCAP-II and III. These two fractions were finally purified by gel filtration to give HCAP-IIa, HCAP-IIIa1, and IIIa2 fractions that had high anti-complementary activities. The HCAP-IIIa1 and IIIa2 consisted of homogeneous polysaccharides. The anti-complementary activities were unaffected by treatment with polymyxin B, indicating that the modes of complement activation were not due to preexisting lipopolysaccharide. The molecular weight and sugar content of HCAP-IIIa2 had potent anti-complementary activity. The highest yields were 55 kDa and 75.9%, and the molar ratio of galactose (Ara:Gal, 1.0:4.6) was higher than other sugars. The crossed immuno-electrophoresis showed that both classical and alternative pathways were activated by HCAP-IIIa2.

Optimization of culture media for the production of β-glucan by Saccharomyces cerevisiae JUL3

Young-Hawn Kim(김영환),Seong-Woo Kang(강성우),Yoon-Seok Song(송윤석),Hyo-Ihl Chang(장효일),Cheol-Won Yun(윤철원),Hyun-Dong Paik(백현동),Chang-Won Kang(강창원),Seung-Wook Kim(김승욱) 한국생물공학회 2005 한국생물공학회 학술대회 Vol.2005 No.10

Poster Session : PS 0975 ; Early Laparoscopic Cholecystectomy without Relief of Jaundice after Ercp is Feasible in Acute Cholangitis and Cholecystolithiasis

( Young Doo Kim ),( Woo Hyun Paik ),( June Sung Lee ),( Kyung Ah Kim ),( Nam Hoon Kim ),( Won Ki Bae ),( Jong Wook Kim ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: In patients with acute cholangitis and cholecystolithiasis, laparoscopic cholecystectomy (LC) is recommended after endoscopic clearance of choledocholithiasis. We aimed to evaluate the optimal time of LC after ERCP Methods: A retrospective review of electronic medical records in single center was performed for 166 patients who underwent elective LC after ERCP between January 2010 and April 2014. We compared the hospital stay, perioperative morbidity and the rate of surgical conversion to open cholecystectomy according to the resolution of jaundice before surgery. Results: The mean age of enrolled patients was 58.6 ± 17.0 years. The enrolled patients were divided into two groups; resolution of jaundice before surgery (group 1, n =72) or not (group 2, n = 94). Initially, there were no signifi cant differences between the groups in terms of age, sex distribution, American Society of Anesthesiologists score, previous surgical history, white blood cell, c-reactive protein, operative time. However, there was no signifi cant difference in postoperative hospital stay between two groups (4.6 ± 3.2 vs. 5.8 ± 4.8 days, p=0.069). Also, there were not statistical differences in conversion rate (1.3% vs. 4.2%, p=0.390) and perioperative morbidity (8.3% vs. 12.7%, p= 0.454). Conclusions: LC wound not be delayed until resolution of jaundice after ERCP since there were no signifi cant differences of perioperative morbidity and surgical conversion rate to open cholecystectomy. Early LC after ERCP may be feasible and safe in patients with acute cholangitis and cholecystolithiasis.

Sequence Analysis of NS4 Region of HCV Isolated from Korean Patient

Paik, Sang-Hoon,Lee, Young-Ik,Kim, Won-Bae,Yang, Jai-Myung The Microbiological Society of Korea 1995 The journal of microbiology Vol.33 No.3

Hepatitis C virus (HCV) has been considered as a mojor causative agent of post-transfusion related non-A, non-B hepatitis. In this study, the cDNA sequence of NS4 region of HCV (HCV-S) obtained from a Korean patient's plasms was determined. Comparative nucleotide sequence analysis between to type II. 67.2% homology to type III, and 66.4% homology to type IV. The putative amino acid sequence homologies to types I, II, III, and IV were 82.8-84.7%, 92.5-95.1%. 72.5, and 71.1%, respectively. This data strongly suggests that HCV-S should be classified as type II. Significant similarities of hydrophobicity profiles and putative transmembranous domains were found in HCV-S and four major prototypes, indicating that the protein structure is similar in spite of the heterogeneities of intertype homologies at the level of the psrimary nucleotide and amino acid sequences.

Defective Interfering HIV - 1 Pseudotypes Carrying Chimeric CD4 Protein

Paik, Soon Young,Park, Seung Won,Ye, Zhi Ping,Schubert, Manfred 생화학분자생물학회 1998 BMB Reports Vol.34 No.6

Chimeric CD4 proteins were assembled. They contained the entire CD4 ectodomain that is linked to different membrane anchors. Membrane anchors consisted of either glucosyl phosphatidyl inositol (gpi), the transmembrane and cytoplasmic regions of HIV -1 Env protein, or the vesicular stomatitis virus G glycoprotein, respectively. The HIV -1 co-receptor CXCR4 and CD4 were independently inserted into viral envelopes. We compared the insertion of six different CD4/CXCR4 constructs into HIV -1 envelopes, as well as their functionality in targeting and specific infection of cells that constitutively express the HIV-1 Env protein. All of the six different HIV-1 (CD4/CXCR4) pseudotypes were able to transduce Env (+) cells at similar efficiency. In addition, stable transduction of the Env (+) recipient cells demonstrated that all chimeric proteins were functional as receptors for Env when inserted into HIV-1 envelopes. In fact, these results demonstrate for the first time a stable transduction by a targeted HIV-1 pseudotype virus.

Clinical Characteristics of Long Term Survivors Following Sorafenib Treatment for Unresectable Hepatocellular Carcinoma: Korean National Multi-Center Retrospective Cohort Study

( Young Youn Cho ),( Su Jong Yu ),( Hye Won Lee ),( Do Young Kim ),( Wonseok Kang ),( Yong-han Paik ),( Pil Soo Sung ),( Si Hyun Bae ),( Su Cheol Park ),( Young Seok Doh ),( Kang Mo Kim ),( Eun Sun Ja 대한간학회 2018 춘·추계 학술대회 (KASL) Vol.2018 No.1

Aims: Sorafenib is the standard systemic therapy for treatment of advanced stage hepatocellular carcinoma (HCC), and progressive HCC after locoregional therapy. The efficacy and safety of the drug in clinical practice have been addressed by several real world studies. However, little data are available regarding clinical factors of good responders following sorafenib treatment. This study aimed to evaluate prognostic factors of long term survivors. Methods: This multi-center retrospective cohort study included 1,605 unresectable HCC patients who received sorafenib treatment between 2007 and 2014 in 9 tertiary centers in Korea. The patients were classified into long-term survivor group (survival longer than 2 years, n=246) or control group (n=1,359). The primary endpoint was prognostic factors on survival for overall patients. Secondary endpoints included time-to-progression and other safety profiles. Results: The patients were predominantly male (83.8%), chronic hepatitis B (77.3%), and Barcelona Clinic of Liver Cancer stage C (78.3%). The median overall survival was 9.0 months. After treatment, 12 patients (0.7%) achieved complete response, and 146 patients (9.1%) achieved partial response by mRECIST criteria. The prognostic factors predicting long-term survival were metformin use (hazard ratio [HR]=2.44; P=0.004), hand foot skin reaction (HR=1.77; P=0.001), and concomittent treatment with chemoembolization or radiotherapy (HR =2.59; P<0.001). Prognostic factors against long-term survival were child pugh score B (HR=0.375; P< 0.001), presence of extrahepatic metastasis (HR=0.625; P=0.002), main portal vein invasion (HR=0.625; P=0.002), and elevated AFP ( >1,000 ng/mL; HR=0.393; P<0.001). Conclusions: This large multi-center retrospective study showed that the objective response was 9.8%, and the proportion of long-term survivors was 15.3% in Korean patients. The prognostic factors predicting long-term survival after sorafenib treatment were hand foot skin reaction, metformin use, concomittent treatment, good liver function, absence of extrahepatic metastasis, low degree of portal vein thrombosis, and low AFP.

Influence of the vitrification solution on the angiogenic factors in vitrificated mouse ovarian tissue

( Won Jun Choi ),( Ji Hye Lee ),( Mi Hyun Park ),( In Young Choi ),( Ji Kwon Park ),( Jeong Kyu Shin ),( Soon Ae Lee ),( Won Young Paik ),( Jong Hak Lee ) 대한산부인과학회 2013 Obstetrics & Gynecology Science Vol.56 No.6

Objective To investigate the effect of the dimethyl sulfoxide (DMSO) and EFS-40 during vitrification on the expression of angiogenic factors in vitrified mouse ovarian tissue. Methods The ovarian tissues were obtained from 5 or 6 weeks aged ICR mouse. Ovarian tissues were divided into four groups: ovarian tissue without cryopreservation (control, group I), ovarian tissue vitrified with 15% DMSO (group II), ovarian tissue vitrified with EFS-40 (group III), and ovarian tissue slowly frozen with 10% DMSO (group IV). Thawing was carried out at room temperature. Levels of messenger RNA (mRNA) and protein for vascular endothelial growth factor-A (VEGF-A) and angiopoietin-2 (Angpt-2) were checked in ovarian tissues of four groups recovered on day 7 after cryopreservation. Reverse transcription-polymerase chain reaction and Western blot analysis were used to identify the levels of angiogenic factors in mouse ovarian tissues. Results Levels of mRNA and protein for VEGF-A and Angpt-2 were significantly decreased in cryopreserved group (group II, III and IV) than control group (group I) (P < 0.05). The significant differences of levels of mRNA and protein for VEGF-A and Angpt-2 between cryopreservation methods were observed (P < 0.05). Group III showed highest expression of mRNA and protein for VEFG-A and Angpt-2 than other cryopreservation groups (P < 0.05). Conclusion These findings suggest that EFS-40 is more efficient vitrification solution for preservation of angiogenic factors than 15% DMSO during vitrification of mouse ovarian tissue. Future studies should investigate to improve the vitrification solution for ovarian tissue vitrification.