The Composition and Productivity of a Grassland in Korea

Kim, Choon M.,Lee, Il K.,Park, Bong k.,Chang, Nam K. 서울대학교 교육대학원 1969 論文集 - 서울대학교 교육대학원 Vol.6 No.-

The vascular florae of the north, northwest and south sides of a stand in the piedmont on the Choon-sung area were composed of 50, 41, and 34 species respectively. The most important of these were Arundinella hirta and Miscanthus sinensis. These two species contributed greatly to the standing crop of live material, which was in excess of 308.66g/m² during the growing season. The peak net productions of organic matter of 61.53g/m, 231.40g/m², and 214.65g/m² for these grasslands were reached in July-August under abundant water conditions, and were largely due to the high productivity of the dominant species such as A. hirta and M. sinensis. The average standing crop of this grassland plant communities was in excess of 571.01g/m² for the one growing season. This value would be increased if the productivity of the moss and algal mats which cover the soil surface during the growing season were included.

Glucose와 Phosphate가 제거된 M-TALP 배지에서의 난구세포 공배양에 의한 임신율 향상에 관한 연구

정범식,장우현,이문희,김지연,방지호,김규현,서태광,Chung, B.S.,Chang, W.H.,Lee, M.H.,Kim, J.Y.,Bang, J.H.,Kim, K.H.,Suh, T.K. 대한생식의학회 1999 Clinical and Experimental Reproductive Medicine Vol.26 No.1

The beneficial effect of glucose and phosphate ions in culture medium on the development of human embryos in vitro has not been fully elucidated. The purpose of this study was to evaluate the influence of fertilization and culture of embryos in glucose/phosphate-free m-TALP medium on pregnancy rates in IVF-ET program. The patients in 244 IVF-ET cycles received GnRH agonist + HMG regimens. A does of 10,000 IU HCG was administered when two or more dominent follicles reached 18mm in diameter. Thirty-six hours after HCG, oocytes were recovered transvaginally using ultrasound guidance. Aspirated oocytes were matured for 4 to 6 h in TCM-199 supplemented with 10% follicular fluid (FF). Insemination was carried out with 50,000 motile spermatozoa in TCM-199 + 10% FF or m-TALP + 5% FF + 5% fetal cord serum (FCS) according to experimental design. After 6 h, oocytes were washed 3 to 4 times and cultured in each fresh medium. After 20 h, oocytes were freed from cumulus/corona cells and examined for the presence of pronuclei. Fertilized oocytes were transferred into each co-culture drops and cultured for further incubation. On day 3, embryo transfer was performed with grade 1 and 2 embryos. Monolayers for co-culture of embryos were prepared by plating $1{\times}10^5$ cumulus cells/ml in 10ul drop of TCM-199 + 10% FF or m-TALP + 5% FF + 5% FCS media 24 h prior to the onset of co-culture. Development to 4 to 16 cell stage was observed at 70x magnification following two days of incubation. Pregnancy was confirmed by detecting increasing serum ${\beta}$-hCG concentrations for 11 days following embryo transfer. Data were analyzed by ${\chi}^2$-test. Oocytes from 244 IVF-ET cycles were randomized. The number of cycles and mean age of patients were 97 and 147, 31.3 yrs and 31.2 yrs for TCM-199 (control) and m-TALP groups, respectively. The mean number of retrieved oocytes/cycle, fertilization rates, number of embryos transferred/ET and pregnancy rates were 11.1 and 10.3, 65.1% and 67.3%, 4.1 and 4.7, 28.9% and 43.8% for TCM-199 and m-TALP groups, respectively. Differences in the pregnancy rates were found between control and m-TALP groups (p<0.05). The pregnancy rate of patients divided according to maternal age groups of ${\leq}30$, 31-35, $36{\leq}$ were 44.4% and 49.0%, 26.1% and 41.3%, 29.2% and 41.2% for control and m-TALP groups, respectively. These data indicate that culture of human embryos in glucose/phosphate-free m-TALP medium improves pregnancy rates.

Photoluminescence Investigation of Thick GaN Films Grown on Si Substrates by Hydride Vapor Phase Epitaxy

M.Yang,H.S.Ahn,J.H.Chang,S.N.Yi,K.H.Kim,H.Kim,김석환 한국물리학회 2003 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.43 No.6

The optical properties of thick GaN lms grown by hydried vapor phase epitaxy (HVPE) using a low-temperature intermediate GaN buer layer grown on a (111) Si substrate with a ZnO thin lm were investigated by using photoluminescence (PL) measurement at 300 K and 77 K. The strong donor bound exciton (DBE) at 357 nm with a full width at half maximum (FWHM) of 15 meV was observed at 77 K. The value of 15 meV is extremely narrow for GaN grown on Si substrate by HVPE. An impurity-related peak was also observed at 367 nm. The origin of impurity was investigated using Auger spectroscopy.

Changes on the Inbreeding Coefficient and Selection Response by Mating Plan of MOET

Lee, K. J 韓國酪農學會 1999 韓國酪農學會誌 Vol.21 No.1

Cordycepin inhibits vascular smooth muscle cell proliferation

Chang, W.,Lim, S.,Song, H.,Song, B.W.,Kim, H.J.,Cha, M.J.,Sung, J.M.,Kim, T.W.,Hwang, K.C. North-Holland ; Elsevier Science Ltd 2008 european journal of pharmacology Vol.597 No.1

Percutaneous transluminal coronary angioplasty (PTCA) is a common procedure for treating atherosclerosis, but its efficacy is limited because of the occurrence of restenosis within 3-6 months after angioplasty. Restenosis is induced by the remodeling of the vessel wall and/or the accumulation of cells and extracellular matrix (ECM) in the intimal layer. Therefore, the matrix metalloproteinase (MMP) system may be a potential therapeutic target for the treatment of restenosis or atherosclerosis. Cordycepin is reported to possess many pharmacological activities including immunological stimulating, anti-cancer, antioxidant, and anti-inflammatory activities. The effect of cordycepin on restenosis has not yet been clearly elucidated. Therefore, in the present study, we tested the role of cordycepin on the MMP system in vascular smooth muscle cells. In the carotid artery of a balloon-injured Sprague-Dawley (SD) rat, neointimal formation was reduced by treatment with cordycepin (20 μM/day, i.p), which inhibited the proliferation of rat aortic smooth muscle cells (RaoSMCs). To investigate the mechanism by which cordycepin inhibits the remodeling of the vessel wall and/or the accumulation of cells and ECM, we examined the activation of MMP systems in collagen type I-activated RaoSMCs. Cordycepin markedly inhibited the activation of MMP-2 and -9 as well as the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) in a dose-dependent manner in collagen type I-activated RaoSMCs. Moreover, cordycepin suppressed cycloxygenase-2 (COX-2) expression related to hyperplasia of RAoSMCs. Taken together, these data suggest that cordycepin may induce antiproliferation in RAoSMCs via the modulation of vessel wall remodeling. Therefore, cordycepin may be a potential therapeutic approach to treat restenosis.

유연(柔軟) 포장재료를 이용한 분말(粉末) 간장의 포장에 관한 연구

장규섭,윤한교,김만수 한국농화학회 1978 Applied Biological Chemistry (Appl Biol Chem) Vol.21 No.3

Fermented soy sauce was dehydrated by spray drying to form powder, and moisture sorption properties of powdered soy sauce with or without cover of the flexible films were examined on different relative humidity by using saturated salt solutions at 30℃. The results obtained were summarized as follows: The equilibrium moisture content of spray-dried soy sauce containing 18.3% moisture was determined to 52% by graphical interpolation method, and E.M.C. of powdered soy sauce covered with plastic films decreased at low relative humidity whereas sharply increased curves were seen at high relative humidity. The rate constant of moisture adsortion K for the power covered with films were 66.2×10^(-5) to 225×10^(-5)/hr., and K' became greater when film having higher water vapo transmission rate was used. The shelf-life of powdered soy sauce covered with Al. foil/P.E. film by Brown formula at the accelerated condition of 38℃, 92% R. H. was the longest period, 164 days compared with any other films used, and the shortest period, 18 days in P.V.C. film.

A Molecular Dynamics Study on the Liquid - Amorphous - Crystalline Transition in a Lennard - Jonesian FCC System : 1. Bulk Crystal

Chang, H . K .,Kim, S . G .,Cheong, B .,Kim, W . M .,Chung, M .,Lee, T . S .,Lee, J . K . 대한금속재료학회(대한금속학회) 1998 METALS AND MATERIALS International Vol.4 No.6

Constant-pressure molecular dynamics simulations are carried out to study the liquid-amorphous-crystalline transition behavior in a model system composed of 500 Leonard-Jones particles under three-dimensional periodic boundary conditions. The critical quenching rate (CQR) for amorphization, i.e., the minimum rate above which no crystallization occurs on quenching, is found to be about 5.52 × 10^(12) K/s for a one-component, unary system. For lower quenching rates, the amorphous phase transforms to a crystalline phase with 0.30.5 of the melting point as the transition temperature. A binary system with a misfit in atomic size shows a smaller CQR, while a system with a higher bond strength for solute atoms requires a greater CQR. A crystallizakion behavior of an amorphous phase on repeating is also studied. Its crystallization temperature depends on the history: the higher the quenching rate for amorphization, the higher the crystallization temperature.

Aerosol delivery of eukaryotic translation initiation factor 4E-binding protein 1 effectively suppresses lung tumorigenesis in K-ras^LA1 mice

Chang, S-H,Kim, J-E,Lee, J-H,Minai-Tehrani, A,Han, K,Chae, C,Cho, Y-H,Yun, J-H,Park, K,Kim, Y-S,Cho, M-H Nature America, Inc. 2013 Cancer gene therapy Vol.20 No.6

Conventional radiotherapy or chemotherapy for the long-term survival of patients with lung cancer is still difficult for treatment in metastatic and advanced tumors. Therefore, the safe and effective approaches to the treatment of lung cancer are needed. In this study, the effect of delivered eukaryotic translation initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1) on lung cancer progression was evaluated. Recombinant adeno-associated virus (rAAV)-M3/4E-BP1 was delivered into 6-week-old K-ras<SUP>LA1</SUP> lung cancer model mice through a nose-only inhalation system twice a week for 4 weeks. Long-term repeated delivery of 4E-BP1 effectively reduced tumor progression in the lungs of K-ras<SUP>LA1</SUP> mice. Reduction of eIF4E by overexpression of 4E-BP1 resulted in suppression of cap-dependent protein expression of basic fibroblast growth factor (bFGF or FGF-2) and vascular endothelial growth factor (VEGF). In addition, delivered 4E-BP1 inhibited the proliferation of lung cancer cells in K-ras<SUP>LA1</SUP> mice model. Our results suggest that long-term repeated viral delivery of 4E-BP1 may provide a useful tool for designing lung cancer treatment.

生藥製劑의 藥劑學的 硏究(Ⅷ) : 當歸 및 그 含有製劑 處方에 따른 成分抽出量에 關한 硏究 Studies on the extraction quantities of the specific components of Angelicae Gigantis Radix

諸今連,崔寶慶,金成煥,崔明姬,張京愛,朴案圭,元奉必,朴萬基 국립보건연구원 1994 국립보건원보 Vol.31 No.2

항균제 내성 대장균의 생태적 분포 Ⅲ. : Rifampicin, nalidixic acid, oxolinic acid와 sulfa 제제에 관하여

이광호,차창룡,국윤호,최명식,김익상,장우현,이승훈,신정식 대한화학요법학회 1983 대한화학요법학회지 Vol.1 No.1

We studied the differences in the MIC distribution of E. coli isolates, from a doctorless remote arwqwang Won. Do province+WD), a leprosarium (So Rock Do=SRD) and Seoul National University Gospital (SNUH> against rifampicin. nalidixic acid, oxolinic acid &a sulfa drags including co-trinoxawle. . So the widespread and prolonged- use of antimicrobial agents is presumed to facilitate the increase of drng-resistapt strains among the normal flora of the residents in a comunity that .the isolates from SNUH- were further divided into two groups, SNUH in-patient (IP) and SNUH out-patient(OP) and the isolates f p m SRD into DDS (isolates. from.leprosy patients.who are taking DDS only) and R f (isolates from leprosy patients who are taking rifampicin-.and DQS) grougs. Nnmber of, E. coli isolates studied were 93 st;ains from SNUH patients (SNUH-IP, 46; SNUF-OP, 43, 150 strains from SRD patients (SRD-DDS, 102; SRD-Rf,' 48) and 119 strains from 'KWD residents. DisLribntion of E. mli- strains a.mording to thir respective MTC's shows that E. coli possesses not only an intrinsic component in resistance (or susceptibility) to the drugs (rif-ampicin, 2-32 pg/ml; nafii%Xic a,cid, 1-16 pg/d; oxolinic acid, * 0.13-2 pg/ml; DDS, 32-1024 pg/ml; sulfadiazine, 2-256 pg/d, sulfamera&& 4-256 pg/ml; sulfadimethoxine, .16~1024 pg/ml; sdfamonornethoxine, ~-12~,pg&d; sulfamethoxazde, 2-128 pg/m&. trimetk0p-Irim, 0.06-2 pg/fnl; co-trimoxwole, 0,. 25-4 pg/ml) but also distinct MIC values of acquired resistance quite different from the intrinsic ones. The .carriage rate of rifampicin resistant strains in the SRD-Rf patients was the higheest among the study:groups while t m e , of SNUH patients and of the KWD residents were equally negligible, as expectediy. Drug-resistant E. coli strains against nalidixic acid and oxolinic acid were uncommon i n the SNUH, SRD and KWD isolates. However, resistance to sulfa drugs were prevalent in the SNUH, SRD and KWD isolates in the decreasing order. Taken together, these results strongly suggest that drug resistznce in Korea is a localized problem in some community under a high selection pressure of antimicrobial agents rather than a nation-wide one. Trimethoprim resistance gave rise to the high-level resistance 'to co-trimoxazde while the sulfamethoxazole resistance t o the low level resistance against the co-trimoxazole.