방향성 연속주조된 Al-Cu합금의 연화처리에 따른 미세조직과 기계적 성질의 변화

제창웅,윤재홍,정동석 國立 昌原大學校 産業技術硏究所 1997 産技硏論文集 Vol.11 No.-

Directionally continuous casted Al-Cu alloys used the components of electronic and electric equipment need to specify the properties of them and optimum drawing condition in order to manufacture a fine wire. Therefore, the present investigation has been carried out for clarifying the changes of macrostructure, microstructure, mechanical properties, and the interrelations of them during annealing heat treatment in order to manufacture a fine wire in directionally continuous casted Al-Cu alloys. Recrystalized grains were not observed at below 200˚C in Al-1%Cu and Al-28%Cu alloys annealed, however recrystalized grains were observed with increasing annealing temperature. Recrystalization was occurred at inclusion/matrix interfaces and also appeared at the inclusions of smaller radius with increasing reduction ratio.

53BP1 is associated with replication protein A and is required for RPA2 hyperphosphorylation following DNA damage

Yoo, Eunjae,Kim, Byung U,Lee, Seung Youn,Cho, Chae Hyun,Chung, Jay H,Lee, Chang-Hun Nature Publishing Group 2005 Oncogene Vol.24 No.35

p53-binding protein 1 (53BP1) acts as an ‘adaptor/mediator’ for transducing DNA damage signals, especially following detection of DNA double-strand breaks. In an effort to broaden our understanding of the protein network surrounding 53BP1, we isolated possible 53BP1 binding partners by co-immunoprecipitation, and identified them via tandem mass spectrometric analysis. The 53BP1-associated proteins included RPA1 and RPA2, two components of the replication protein A (RPA) complex. The presence of RPA components in the immunoprecipitates was confirmed by immunoblotting, and we found that the association between 53BP1 and RPA2 was disrupted following DNA damage induced by treatment with camptothecin, a topoisomerase I inhibitor. To investigate the functional meaning of the 53BP1 and RPA interaction, we established U2OS osteosarcoma cell lines stably expressing dominant-negative fragments of 53BP1. We found that camptothecin-induced RPA2 phosphorylation was inhibited in these cells, and also following 53BP1 knockdown by siRNA transfection. On the cellular level, camptothecin-induced apoptosis was augmented in the dominant-negative cell lines, resulting in increased chemosensitivity to this drug. Taken together, these results suggest that 53BP1 is involved in DNA damage-induced RPA2 hyperphosphorylation, and inhibition of 53BP1 function may sensitize cancer cells to camptothecin treatment.Oncogene (2005) 24, 5423–5430. doi:10.1038/sj.onc.1208710; published online 18 April 2005

항진균물질을 생산하는 Streptomyces fimbriatus AF21-3의 분리 및 동정

장주현,김정완,이우윤,윤영준,이경림,김승곤,이태수 인천대학교 2000 基礎科學論文集 Vol.11 No.1

Actinomycetes were isolated from soil to find new antibiotics. An active antimicrobial compound was isolated from the culture filtrate of Actinomycetes AF 21-3. The Actinomycetes strain which showed strong antifungal activity against Candida tropicalis and Microsporum gypseum was identified as Streptomyces fimbriatus and named as Streptomyces fimbriatus AF 21-3.

RaRF confers RA resistance by sequestering RAR to the nucleolus and regulating MCL1 in leukemia cells

Youn, H,Lee, H-K,Sohn, H-R,Park, U-H,Kim, E-J,Youn, B,Um, S-J Macmillan Publishers Limited, part of Springer Nat 2018 Oncogene Vol.37 No.3

Retinoic acid (RA) has broad clinical applications for the treatment of various cancers, particularly acute promyelocytic leukemia. However, RA-based therapy is limited by relapse in patients associated with RA resistance, the mechanism of which is poorly understood. Here, we suggest a new molecular mechanism of RA resistance by a repressor, named RA resistance factor (RaRF). RaRF suppressed transcriptional activity of the RA receptor (RAR) by directly interacting with and sequestering RAR to the nucleolus in response to RA. RaRF was highly expressed in RA-resistant leukemia cells and its expression was strongly correlated with RA sensitivity. MCL1 was upregulated by RA treatment upon RaRF depletion, accompanying leukemic myeloblast differentiation, which is negatively regulated by ectopic RaRF expression. Collectively, we propose that RaRF may be a factor in the resistance mechanism and thus a potential target for leukemia therapy using RA.

Evaluation of antioxidant, xanthine oxidase, tyrosinase inhibition activities, phenolic acids and flavonoid contents from the fruiting bodies of Pleurotus ciitrinopileatus

Youn Jeong Cha,Jeong Hwa Kim,Mi Ja Shim,Pyung Gyun Shin,Jong Chun Cheong,Young Bok Yoo,U Youn Lee,Tae Soo Lee 한국버섯학회 2010 한국버섯학회지 Vol.8 No.4

Pleurotus citrinopileatus was successfully cultivated and commercially available in Korea. The antioxidant, xanthine oxidase, tyrosinase inhibitory activities and polyphenol contents of fruiting bodies of Pleurotus citrinopileatus extracted with acetone, hot water and methanol (hereinafter referred to Fr. Ace, Fr. HW and Fr. MeOH). The antioxidant activities on β-carotene-linoleic acid in the Fr. Ace, Fr. HW and Fr. MeOH were 96.12%, 94.21% and 96.52%, respectively at the concentration of 20 mg/ml. Xanthine oxidase inhibition activity in the Fr. Ace, Fr. HW and Fr. MeOH were 30.12%, 35.42% and 29.02%, respectively at the concentration of 5 mg/ml. Tyrosinase inhibition activity in the Fr. Ace, Fr. HW and Fr. MeOH were 58.78%, 49.25% and 63.29%, respectively at the concentration of 1.0 mg/ml. Total polyphenol contents in the Fr. Ace, Fr. HW and Fr. MeOH were 18.99 mgGAEs/g, 16.73 mgGAEs/g and 18.66 mgGAEs/g. These experimental results suggested that fruiting bodies of P. citrinopileatus contained good physio-chemical substances for promoting human health.

Evaluation of antioxidant, xanthine oxidase, tyrosinase inhibition activities, phenolic acids and flavonoid contents from the fruiting bodies of Pleurotus ciitrinopileatus

Youn Jeong Cha,Jeong Hwa Kim,Mi Ja Shim,Pyung Gyun Shin,Jong Chun Cheong,Young Bok Yoo,U Youn Lee,Tae Soo Lee 한국버섯학회 2010 한국버섯학회 국제학술대회 Vol.6 No.-

보문 : 신령버섯(Agaricus brasiliensis) 자실체 추출 조다당류의 항암 및 면역증강 작용

차윤정 ( Youn Jeong Cha ),김정화 ( Jeong Hwa Kim ),이태수 ( Tae Soo Lee ),이우윤 ( U Youn Lee ) 한국균학회 2011 韓國菌學會誌 Vol.39 No.1

Agaricus brasiliensis, one of edible mushroom belonging to Basidiomycota, has been used for curing gastric ulcer and stomach cancer of human beings and also known to have good inhibitory effects on sarcoma 180 and Ehrlich carcinoma of mice. Neutral saline soluble (0.9% NaCl), hot water soluble and methanol soluble substances (hereinafter referred to Fr. NaCl, Fr. HW and Fr. MeOH, respectively) were prepared from fruiting body of the mushroom. β-glucan and total protein contents were identify from fractions of edible mushrooms extract. The β-glucan and protein contents of all fractions of the mushrooms ranged from 21.54~32.31% and 0.16~9.34%, respectively. In vitro cytotoxicity tests, crude polysaccharides were not cytotoxic against cancer cell lines such as Sarcoma 180, HT-29, NIH3T3 and RAW 264.7 at the concentration of 10~2000 μg/ml. Intraperitoneal injection with crude polysaccharides exhibited life prolongation effect of 18.8~50.6% in mice previously inoculated with Sarcoma 180. Fr. HW increased the numbers of spleen cell by 1.2 fold at the concentration of 200 μg/ml compared with control. Fr. MeOH and Na improved the immuno-potentiating activity of B lymphocyte by increasing the alkaline phosphatase activity by 1.6 fold compared with control at the concentration of 50~500 μg/ml. Fr. Na generated 15.9 μM of nitric oxide (NO) when cultured with RAW 264.7 at the concentration of 200 μg/ml, while lipopolysaccharide, a positive control, produced 3.7 μM. The Fr. NaCl, Fr. HW and Fr. MeOH increased the secretion of TNF-α, IL-1β, Il-2 and IL-6 by 2.2 times compared with the control group. Fr. Na increased the numbers of peritoneal exudate cells by 4 folds at the concentration of 50mg/kg compared with control. Circulating leukocytes increased by 2.7 folds when Fr. HW from A. brasiliensis was inoculated at the concentration of 50 mg/kg body weight. The hematological and blood chemical analysis of the 3 fractions did not show any difference in blood compositions and enzyme activities compared with the control group (p<0.05). Therefore, the experimental results suggested that crude polysaccharides extracted from A. brasiliensis contain antitumor and immuno-potentiating activities against Sarcoma 180 in ICR mice.

A Study on the RNA, DNA Contents at Each Part of Each Year Ginseng Root

LEE, U YOUN,LEE, GAPDUK,LEE, MYUNGSUN 동국대학교 대학원 1977 연구논집 Vol.7 No.

A Study on the RNA, DNA Contents at Each Part of Each Year Ginseng Root

LEE, U YOUN,LEE, GAPDUK,LEE, MYUNGSUN 동국대학교 대학원 1977 大學院硏究論集-東國大學校 大學院 Vol.7 No.-

This was to study the amount of Nutleic acid in three parts (head, trunk, tail) of each year (from two year roots to six year roots) ginseng cultivated in Kang Wha, Korea. The results were as follows; 1). In head parts, the highest content of RNA was contained in five year ginseng roots and the lowest in two year ginseng roots. RNA content of siz year ginseng roots falled down rapidly. DNA content was also same phenomenon as RNA content. 2). In trunk parts, the relative ratio of RNA and DNA contents for each year roots was as like in head parts. However the lowest amount of total Nucleic and was contained in this part among the three parts. 3). In tail parts, th amount of RNA and DNA was also as like the others. Total Nucleic acid content was the highest in this part among the three parts. Ginseng was recorded for the first time in the world as a name of Sam (蔘) at era of Won Dinasty (B.C.34-48), ancient China. Korean ginseng (Panax Ginseng C.A. Meyer) has ever increasing on its efficency since prehistoric era in the Orient. Especilly chemical components of ginseng has studied for a long time by scientists. The first report about ginseng components was by Garriques in 1854. He separated Saponin from American ginseng (Panax quinquefolium L.) and named it Panaquilon. Now among the various components of Korean ginseng, triterpene glycosides of dammarane series which were known to be the effective components and also known to be the ginseng specific component, were discussed with more interest. Lee, T.N. and T.W. Kwon reported in 1962 the composition of free sugars in Korean ginseng was determined by use of the ion exchange chromatography and anthrone reaction. The free sugars were sucrose(8.5%), fructose(0.5%), and glucose(0.4%), Takiura, K. and I. Nakagawa reported in 1963 that seperatory determination of moncsaccharides and disaccharides contained in the aqueous extract of Ginseng Radis was carried out. As the monosaccharide, D-fructose and D-glucose where identified, the total amount of these monosaccharides in the dried root was 1.5%, disaccharides were 3.8%, and maltcse were separated as crystals. These were identified by the partition column chromatography using powdered cellulose. Peter, A.M. partially analized American ginseng (Aralia quinquefolia) roots to determine the nitrogen(1.600%), phosphoric acid (0.535%), potash(0.776%), lime(0.856%), cruce ash (5.278%) in the roots. Basic components of ginseng were known as water(66.73%), ash(1.46%), fat(0.33%), cellulose(3.67%), nitrogen(0.80%), pure protein(5.04%), soluable non-nitrogen material (22.03%), sucrose (8.53%), fructose (0.50%), glucose (0.97%), fumaric, succinic, malic, citric, tartaric, oleic, linoleic, several other fatty acids, an essential oil(probably the sesquiterpene previously named panacene), several glucosides of unknown structure and a yellow pigment. Chromosomes consist predominantly of proteins and nucleic-acid. Most important group of chromosome constituents, the nucleic acids, were discovered by the Swiss scientist Meischer in Tubingen. Nucleic acids are the carriers of genetic information. The amount of RNA and DNA in the three parts(head, trunk, tail) of each year ginseng cultivated in Kang Wha, Korea is reported few.

The Spectral Characteristic of Far - infrared Radiant Ceramics

( U Hyon Park,Youn Shick Ha ) 한국광물학회 1997 ENVIRONMENTAL MINERALOGY Vol.- No.-