Imazethapyr 유도체의 제초활성에 미치는 3-(N-methyl-N-(X)-치환-phenylaminooxoacetyl) group의 영향

성낙도,김현재,장해성,김대황 충남대학교 생물공학연구소 1993 생물공학연구지 Vol.3 No.-

새로운 25종의 Imazethapyr 유도체, (2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)-3-(N-methyl-N-(X)치환 -phenylaminooxoacetyl)-5-methylpyridine)들을 합성하여 치환기(X) 변화에 따른 발아 전 후, 피(Echinochla crus-galli.)의 제초활성에 미치는 3-(N-methyl-N-(X)치환 -phenylaminoozoacetyl) group의 영향을 검토한 바, 발아 전보다 발아 후의 제초활성에 더 큰 영향을 미침을 알 수 있었다. 발아 후의 제초활성은 X-치환기의 전자밀게 효과와 입체상수(E_s)에 의존적이었으며 가장 큰 제초활성을 나타내는 화합물로는 bulky(E_s<O)하고 전자밀게 (б<O)가 치환된 화합물, 15(4-t-butyl group)와 20(3,5-dimethyl group)이었다. 그리고 높은 제초활성을 나타낼 것으로 예상되는 화합물의 조건들이 검토되었다. (1993년 9월 18일 접수, 1993년 9월 22일 수리). New twenty five Imazethapyr derivatives, [2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)-3-(N-methyl-N-X(sub.)-phenylaminooxoacetyl)-5-methylpyridine] were synthesized. and The quantitative structure activity relationships (QSARs) between their post-emergence herbicidal activity(pI_50) values in vivo against Barnyard grass (Echinochloa crus-galli) and physicochemical parameters of substituents(X) of 3-(N-methyl-N-X(sub.)-phenylaminoo-xoacetyl) group have been studied. From the basis on the findings, in case of post-emergence, the activities were dependent on the steric constant(E_s<θ)and electron donating (o<O) effect by subsitituents(X) of 3-(N-methyl-N-X(sub.)phenylaminooxacetyl) group. Therefore, The most effective compound, 15 (4-t-butyl group) and 20 (3,5-dimethyl group) were examined in this study. And the conditions on the compounds predicted to show higher herbicidal activity were also discussed.

Effect of annealing of graphene layer on electrical transport and degradation of Au/graphene/n-type silicon Schottky diodes

Kim, D.J.,Kim, G.S.,Park, N.W.,Lee, W.Y.,Sim, Y.,Kim, K.S.,Seong, M.J.,Koh, J.H.,Hong, C.H.,Lee, S.K. Elsevier Sequoia 2014 JOURNAL OF ALLOYS AND COMPOUNDS Vol.612 No.-

We have investigated the effect of annealing of graphene sheets on the electrical properties of Au/graphene/n-type silicon Schottky diode. Large scale graphene sheets were grown by chemical vapor deposition and then annealed at 300, 400, and 500<SUP>o</SUP>C; one sheet was left un-annealed as the control. The diodes were fabricated by transferring the graphene sheets directly onto n-type Si substrates and the current-voltage (I-V) and capacitance-voltage (C-V) characteristics were evaluated. The average values of the Schottky barrier height (SBH) and ideality factor (η) for the as-fabricated Au/graphene/n-type silicon Schottky diode from I-V measurements were determined to be ~0.8+/-0.01eV and ~1.79+/-0.05, respectively, whereas the SBH from C-V measurements was ~0.89+/-0.01eV. The electrical transport characteristics measured at room temperature indicated that annealing of graphene sheet prior to the transfer of the graphene onto the n-Si substrates significantly reduces the electric degradation of the Schottky diodes, even though no distinct differences in other electric properties, including ideality factors and SBHs, before or after annealing of the graphene sheets were observed. Thus, by simply annealing the graphene sheets at 500<SUP>o</SUP>C, we found that the Au/graphene/n-type silicon Schottky diode showed an approximately 3.3-fold lower series resistance as compared with the un-annealed Schottky diode under air exposure of up to 7days. These annealed diodes showed significantly reduced electrical degradation by removing the potentially trapped H<SUB>2</SUB>O and/or O<SUB>2</SUB> at the interface between the graphene layer and the n-Si substrate.

Observation of a d-wave gap in electron-doped Sr₂IrO₄

Kim, Y. K.,Sung, N. H.,Denlinger, J. D.,Kim, B. J. NATURE PUBLISHING GROUP 2016 NATURE PHYSICS Vol.12 No.1

<P>High-temperature superconductivity in cuprates emerges out of a highly enigmatic 'pseudogap' metal phase. The mechanism of high-temperature superconductivity is probably encrypted in the elusive relationship between the two phases, which spectroscopically is manifested as Fermi arcs-disconnected segments of zero-energy states-collapsing into d-wave point nodes upon entering the superconducting phase. Here, we reproduce this distinct cuprate phenomenology in the 5d transition-metal oxide Sr2IrO4. Using angle-resolved photo-emission, we show that the clean, low-temperature phase of 6-8% electron-doped Sr2IrO4 has gapless excitations only at four isolated points in the Brillouin zone, with a predominant d-wave symmetry of the gap. Our work thus establishes a connection between the low-temperature d-wave instability and the previously reported high-temperature Fermi arcs in electron-doped Sr2IrO4 (ref. 1). Although the physical origin of the d-wave gap remains to be understood, Sr2IrO4 is the first non-cuprate material to spectroscopically reproduce the complete phenomenology of the cuprates, thus offering a new material platform to investigate the relationship between the pseudogap and the d-wave gap.</P>

Pulse Shape Discrimination of Nuclear Recoil and Electron Recoil Events With a NaI(Tl) Crystal for Dark Matter Search

Kim, K. W.,Adhikari, G.,Adhikari, P.,Choi, S.,Ha, C.,Hahn, I. S.,Jeon, E. J.,Joo, H. W.,Kang, W. G.,Kim, H. J.,Kim, N. Y.,Kim, S. K.,Kim, Y. D.,Kim, Y. H.,Lee, H. S.,Lee, M. H.,Leonard, D. S.,Oh, S. Y IEEE 2016 IEEE transactions on nuclear science Vol.63 No.2

<P>In order to investigate discrimination between nuclear recoil and electron recoil events for the KIMS-NaI dark matter search experiment, we measured the pulse shapes produced by neutrons and gamma rays in a NaI(Tl) crystal. Relatively good pulse shape discrimination (PSD) power due to high light output of recently developed crystals makes it possible to test whether the annual modulation signal observed by the DAMA/LIBRA experiment is caused by nuclear recoil events. We applied the PSD to underground data taken with a 9.15 kg low-background and high-light-output NaI(Tl) crystal for 134 days. Good agreement between underground data and electron recoil events was observed.</P>

Disposition and metabolism of (2S,3S,4R)-N''-cyano-N-(6-amino-3,4-dihydro-3-hydroxy-2-methyl-2-dimethoxy methyl-2H-benzopyran-4-yl)-N'-benzylguanidine, a novel neuroprotective agent for ischemia-reperfusion damage, in rats

Kim, N. S.,Yoo, H. H.,Lee, M. W.,Kim, H. S.,Kim, D. H. Taylor & Francis 2007 Xenobiotica Vol.37 No.5

<P> The metabolism and disposition of KR31378 (a benzopyran derivative and a novel neuroprotective agent) were investigated following single oral or intravenous administration of [14C]-KR31378 to rats. [14C]-KR31378 was rapidly absorbed after oral dosing with an oral bioavailability of greater than 71%. The maximum plasma concentration and area under the curve of total radioactivity in rat plasma increased proportionally to the administered dose. KR31378 was distributed over all organs and tissues except for brain, eyeball and testis, and declined by first order kinetics up to 24 h after dosing. Excretion of the radioactivity was 29.5% of the dose in the urine and 58.5% in the feces within 2 days after oral administration. Biliary excretion of the radioactivity in bile duct-cannulated rats was about 66.0% for the first 24 h. KR31378 was extensively metabolized by ring hydroxylation, O-demethylation, oxidation and reduction with subsequent N-acetylation and O-glucuronide conjugation. N-acetylated conjugates (M2, M10, M11, M12, M14, and M15) were identified as the predominant metabolites in rats.</P>

군장병의 헌혈을 통한 말라리아 전파의 위험성에 대한 조사

임채승,김영기,이갑노,염용태,김순덕,김대성,황유성,오홍범,김두성 대한감염학회 1997 감염 Vol.29 No.2

목적:국내 헌혈 혈액에서 전염병 감염 방지를 위해 시행하는 감염표지자 중 말라리아를 검출하려는 노력은 최근의 비무장지대 내의 군장병에서의 말라리아 재발생에도 불구하고 활성화 되어 있지 않다. 일반적으로 말라리아가 토착화 된 지역을 거주하거나 여행한 사람 중 말라리아에 걸렸거나 치료한 경력 있는 사람은 치료가 끝난 후라도 3년내에는 헌혈을 금지하도록 규정하고 있다. 저자들은 국내 헌혈의 중요 부분(57.8%)을 차지하는 군인에서 헌혈시 말라리아 전파의 위험성을 파악하고자 본 조사를 실시하였다. 방법:1995년 5월에서 1996년 10월까지 군병원에 입원한 환자중 말라리아로 확진된 174명의 환자에서 면담 및 입원 기록을 추적하여 병력과 헌혈 기록을 확인 한 뒤 헌혈장소, 헌혈일, 헌혈 기록을 확인 한 뒤 헌혈장소, 헌혈일, 헌혈 횟수를 조사하여 환자의 증상 발병일과의 간격 및 연관성 분석하였고 이를 기준으로 공혈 혈액의 수혈시 말라리아의 전파 위험성을 평가하였다. 결과:전체 174명의 환자중에서 1회라도 헌혈을 시행한 사람은 70.7%인 123명에 해당하였고 환자의 증상 시작일과 헌혈일과의 간격은 2일에서 평균 2750일(평균 377알, 표준편차 488일)의 분포를 보였다. 증상시작일과 헌혈일의 간격이 3년 이내인 경우는 전체의 87.8%에 해당하였다. 말라리아 치료후 헌혈을 실시한 경우는 (n=18) 모두 치료 후 3년 이내에 헌혈을 하였다. 헌혈장소는 토착형 말라리아의 호발 지역과 동일하였는데 경기도 파주시(40%)와 연천군(29%) 및 철원(15.5%) 기타(15.5%)순이었다. 결론:한국에서 토착형 말라리아 군인 환자들의 병력조회에서 헌혈에 의한 전염가능성이 존재하는 기간 내에 헌혈이 적지 않게 실시되고 있어서 이들 지역에서의 군헌혈을 실시하는 경우 엄격한 헌혈자 선별기준 적용되어야 할 것으로 생각된다. Background: Screening of donor blood for malaria has not been activated in Korea yet in spite of the recent resurgence of tertian malaria among Korean army soldiers in Delimited Militarized Zone areas. Prospective donors(travellers, immigrants, refugees, citizens or residents) following a visit to or coming from and endemic area who have had malaria or taken antimalarial prophylaxis should be deferred for 3 years after cessation of therapy or after depature from malarial area. We studied the risk of the transmission of malaria, especially through army blood donation which comprised up to 57.8% of whole blood donation in Korea. Methods: The data were collected by personal interview and review of donation records of Korea Red Cross Center and medical records from 174 army soldiers with malaria who admitted to Army Hospital from May 1995 to October 1996. We analysed the time interval between onset of illness and blood donation, and geographic distribution of the patients. Results: About 70.7%(123/174) of the patients donated blood before the onset of illness, and the internal between blood donation and onset of illness ranged from 2 days to 2,750 days (mean 377, standard deviation488). Patients who donated blood within 3 years before onset of illness were 87.8%(n=108) of the total blood donation. All donation (n=18) after treatment were within 3 years from 46 days to 342 days(mean 138, standard deviation 80.7). The frequent of blood donations were from the prevalent areas of malaria such as Pajoo City(40%), Younchon Kun(29%), Cholwon Kun(15.5%) and others(15.5%). Conclusion: We showed that donated army blood a risk of malaria transmission. Therefore the blood bank needs to set strict guidelines for blood donation especially from Korean army soldiers to control malaria transmission.

Imazethapyr 유도체의 제초활성에 미치는 3 - ( N - methyl - N - ( X ) - 치환 - phenylaminooxoacetyl ) group 의 영향

성낙도(N . D . Sung),김현재(H . J . Kim),장해성(H . S . Chang),김대황(D . W . Kim) 한국응용생명화학회 1993 Applied Biological Chemistry (Appl Biol Chem) Vol.36 No.5

New twenty five Imazethapyr derivatives, [2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)-3-(N-methyl-N-X(sub.)-phenylaminooxoacetyl)-5-methylpyridine] were synthesized. and The quantitative structure activity relationships (QSARs) between their post-emergence herbicidal activity(pI_(50)) values in vivo against Barnyard grass (Echinochloa crus-galli) and physicochemical parameters of substituents(X) of 3-(N-methyl-N-X(sub.)-phenylaminooxoacetyl) group have been studied. From the basis on the findings, in case of post-emergence, the activities were dependent on the steric constant(E_s$lt;0) and electron donating (σ$lt;0) effect by subsitituents(X) of 3-(N-methyl-N-X(sub.)phenylaminooxoacetyl) group. Therefore, The most effective compound, 15 (4-t-butyl group) and 20 (3,5-dimethyl group) were examined in this study. And the conditions on the compounds predicted to show higher herbicidal activity were also discussed.

Genome-wide transcriptome analysis of expression in rice seedling roots in response to supplemental nitrogen

Chandran, A.K.N.,Priatama, R.A.,Kumar, V.,Xuan, Y.,Je, B.I.,Kim, C.M.,Jung, K.H.,Han, C.d. G. Fischer 2016 Journal of plant physiology Vol.200 No.-

<P>Nitrogen (N) is the most important macronutrient for plant growth and grain yields. For rice crops, nitrate and ammonium are the major N sources. To explore the genomic responses to ammonium supplements in rice roots, we used 17-day-old seedlings grown in the absence of external N that were then exposed to 0.5 mM (NH4)(2)SO4 for 3 h. Transcriptomic profiles were examined by microarray experiments. In all, 634 genes were up-regulated at least two-fold by the N-supplement when compared with expression in roots from untreated control plants. Gene Ontology (GO) enrichment analysis revealed that those upregulated genes are associated with 23 GO terms. Among them, metabolic processes for diverse amino acids (i.e., aspartate, threonine, tryptophan, glutamine, L-phenylalanine, and thiamin) as well as nitrogen compounds are highly over-represented, demonstrating that our selected genes are suitable for studying the N-response in roots. This enrichment analysis also indicated that nitrogen is closely linked to diverse transporter activities by primary metabolites, including proteins (amino acids), lipids, and carbohydrates, and is associated with carbohydrate catabolism and cell wall organization. Integration of results from omics analysis of metabolic pathways and transcriptome data using the MapMan tool suggested that the TCA cycle and pathway for mitochondrial electron transport are co-regulated when rice roots are exposed to ammonium. We also investigated the expression of N-responsive marker genes by performing a comparative analysis with root samples from plants grown under different NH4+ treatments. The diverse responses to such treatment provide useful insight into the global changes related to the shift from an N-deficiency to an enhanced N-supply in rice, a model crop plant. (C) 2016 Elsevier GmbH. All rights reserved.</P>

Implication of intracellular ROS formation, caspase-3 activation and Egr-1 induction in platycodon D-induced apoptosis of U937 human leukemia cells

Shin, D.Y.,Kim, G.Y.,Li, W.,Choi, B.T.,Kim, N.D.,Kang, H.S.,Choi, Y.H. Masson Pub. USA, Inc 2009 BIOMEDICINE AND PHARMACOTHERAPY Vol.63 No.2

Platycodon D is a major constituent of triterpene saponins found in the root of Platycodon grandiflorum, Platycodi Radix, which is widely used in traditional Oriental medicine for the treatment of many chronic inflammatory diseases. The results of previous studies have shown that this compound has in vitro growth-inhibitory activity in human cancer cells, however, the mechanism by which this action occurs is poorly understood. In this study, we examined the effects of platycodon D on the production of reactive oxygen species (ROS) and evaluated the association of these effects with apoptotic tumor cell death using a human leukemic U937 cell line. The results of this study demonstrate that platycodon D mediates ROS production, and that this mediation is followed by a decrease in mitochondrial membrane potential (MMP, ΔΨ<SUB>m</SUB>), activation of caspase-3, and cleavage of poly (ADP-ribose) polymerase (PARP). Both the cytotoxic effects and apoptotic characteristics induced by platycodon D treatment were significantly inhibited by z-DEVD-fmk, a caspase-3 inhibitor, which demonstrates the important role that caspase-3 plays in the observed cytotoxic effect. Additionally, the transcription factor early growth response-1 (Egr-1) gene was transcriptionally activated and the levels of non-steroidal anti-inflammatory drug (NSAID)-activated gene-1 (NAG-1) protein were elevated in platycodon D-treated U937 cells. However, the quenching of ROS generation in response to treatment with a ROS scavenger, N-acetyl-l-cysteine, reversed the platycodon D-induced apoptosis effects via inhibition of Egr-1 activation, ROS production, MMP collapse, and the subsequent activation of caspase-3. Although further studies are needed to demonstrate that increased expression of Egr-1 by platycodon D leads directly to NAG-1 induction and subsequent apoptosis, our observations clearly indicate that ROS induced through Egr-1 activation are involved in the early molecular events involved in the platycodon D-induced apoptotic pathway.

Imazapyr 유도체의 제초활성에 미치는 3 - ( N - methyl - N ( X ) - 치환 - Phenylaminooxoacetyl ) Group 의 영향

성낙도(N . D . Sung),유택승(T . S . Ryu),장해성(H . S . Chang),김대황(D . W . Kim) 한국응용생명화학회 1994 Applied Biological Chemistry (Appl Biol Chem) Vol.37 No.6

New seventeen imazapyr derivatives, 2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)-3-(N-methyl-N-X(sub.)-phenylaminooxoacetyl)pyridine, 6 were synthesized and their pre-emergence herbicidal activity(pI_(50) in vivo against Corn (Zea mays L.) and Pigweed (Amaranthus viridis L.) were studied by the pot test under paddly conditions. (quantitative structure activity relationships (QSARs) were analyzed using the physicochemical parameters of substituent(X) on the phenyl ring of 3-(N-methyl-N-X(sub.)-phenylaminooxoacetyl) group and regression analysis. The herbicidal activities were related to the steric effect of X-substituent. The effect was rationalized by paraholic function of MR and L₁, where the optimal values were MR=5.56 (Zea mays L.) and L₁=3.34 Å (Amaranthus viridis L.). Among them, 2,5-difluoro substituted compound, 6i showed good herbicidal activity against Pigweed with excellent tolerance to Corn.