置換 Trifluoroacetanilide類의 加水分解에 대한 Triamine-copper(Ⅱ)-imidazolate 錯和合物의 觸媒 效果

노재근,홍순영,김상진,김창석 漢陽大學校 環境科學硏究所 1994 環境科學論文集 Vol.15 No.-

Triamine이 tridentate ligand를 형성하는 triamine-copper(Ⅱ)-imidazolate complex와 triamine-copper(Ⅱ)-benzimidazolate complex를 합성하여 imidazole과 이 complex들의 촉매작용을 치환 trifluoroacetanilide의 가수분해에 대하여 UV spectrophotometric method로 조사하였다. p-Nitro-2,2,2-trifluoroacetanilide의 가수분해 반응속도는 pH 7, 8에서는 완만히 증가하다가 pH 9, 10에 이르러 급격히 증가하였고 다시 pH 11, 12에서는 서서히 증가하였다. 이때 triamine-copper(Ⅱ)-imidazolate complex는 pH 7∼9에서는 imidazole보다 촉매효과가 더 컸고, pH 10∼12에서는 imidazole보다 작은 촉매효과를 나타내었다. 또한 촉매의 농도가 커질수록 기질의 가수분해 반응속도값은 증가하였으나triamine-copper(Ⅱ)-benzimidazolate의 경우에는 농도가 커질수록 오히려 반응속도가 감소했다. 치환기와 반응속도 사이에는 Hammett rule이 잘 적용되었고 전자끄는 치환기에 의해 반응이 촉진되었다. p-Nitro-2, 2, 2-trifluoroacetanilide의 이들 촉매에 의한 가수분해 반응에서 solvent deuterium kinetic isotope effect(??/??)는 pH 7에서는 2.25∼2.27, pH 10에서는 1.44로서 중성 수용액 내에서는 general basecatalysis path로, 그리고 염기성 수용액 내에서는 nucleophilic catalysis로 진행하는 것을 알 수 있었다. Triamine-copper(Ⅱ)-imidazolate complex(C₂C₂CuIm) and triamine-copper(Ⅱ)-benzimidazolate complex(C₂C₂CuBzIm in which triamine serves as a tridentate ligand were synthesized. The catalytic actions of these complexres, comparing with imidazole, for the hydrolysis of substituted trifluoroacetanilide were observed by a UV spectrophotometric method. The rate of hydrolysis of p-nitro-2, 2, 2-trifluoroacetanilide(p-NO₂-TFA) was increased rapidly at pH 9 and 10 but slowly at pH 11 and 12. At pH 7∼9 the catalytic effect C₂C₂CuIm was larger than that of imidazole itself, however the effect of C₂C₂CuIm was smaller than that of imidazole at pH 10∼12. And hydrolysis rate of p-NO₂-TFA was increased with increasing concentration of catalysis, but in case of C₂C₂CuIm, hydrolysis rate of p-NO₂-TFA was decreased with increasing catalyst concentraration. The tate of hydrolysis was enhanced by electron-withdrawing substituents obeying well the Hammett rule. In the hydrolysis of p-NO₂-TFA with these catalysts, solvent deuterium kinetic isotope effect(??/??) was found to be 2.25∼2.27 at pH 7 and 1.44 at pH 10 suggesting that the catalytic hydrolysis proceeds by a general base catalysis path at a neutral teaction medium(pH 7) and proceeds by a mucleophilic catalysis path at an alkaline reaction medium(pH 10).

4-Nitrophenyl-α-D-glucopyranoside의 加水分解에 대한 Trimaine-copper(Ⅱ)-imidazolate 錯化合物의 觸媒 效果에 關한 硏究

노재근,홍순영,고상연,김창석 漢陽大學校 基礎科學硏究所 1994 基礎科學論文集 Vol.13 No.-

Triamine이 tridentate ligand를 형성하는 몇가지 triamine-copper(Ⅱ)-imidazolate complex들을 합성하여 이 complex들의 촉매작용을 4-nitrophenyl-α-D-glucopyranoside의 가수분해에 대하여 UV spectrophotometric method로 조사하였다. 이 complex들은 imidazole이나 imidazolate자체에 비해서 비교적 좋은 촉매 효과를 나타내었다. 4-nitrophenyl-α-D-glucopyranoside의 가수분해 반응속도는 반응 매체의 pH가 증가할 수록 또한 촉매의 농도가 커질수록 증가하였다. Triamine-copper(Ⅱ)-imidazolate complex는 imidazole 그 자체에 비하여 1.99∼2.84배의 비교적 큰 촉매효과를 나타내었다. 또한 imidazole 및 triamine-copper(Ⅱ)-imidazolate complex의 촉매효과는 imidazole ring의 전자 주는 기에 의해서 증가하고, 전자 끄는 기에 의해서는 감소하였다. Triamine-copper(Ⅱ)-imidazolate-complex는 triamine이 copper(Ⅱ)와 6-membered ring을 이룰 때 보다 5-membered ring을 이룰 때가 촉매 효과가 약간 향상되는 것으로 보아 이 구조로 형성된 complex가 보다 안정한 구조를 하고 있음을 알 수 있다. 4-nitrophenyl-α-D-glucopyranoside의 구조가 acetal의 구조를 가짐에도 불구하고 일반적인 acetal과는 달리 높은 pH에서 가수분해 반응이 더 잘 진행되었으며 이 현상은 설명할 수 있는 반응 메카니즘을 제시하였다. Several triamine-copper(Ⅱ)-imidazolate complexes in which triamine serves as a tridentate ligand were synthesized. Catalytic action of these complexes for the gydrolysis of 4-nitrophenyl-α-D-glucopyranoside were observed by a UV spectrophotometric method. These complexes showed a marked catalytic action enhacing the hydrolysis of 4-nitrophenyl-α-D-glucopyranoside in comparison with imidazole or imidazolate alone. It was observed that the higher the pH and the concentration of catalyst, the faster the rate of hydrolysis of 4-nitrophenyl-α-D-glucopyranoside, and triamine-copper(Ⅱ)-imidazolate complex showed 1.99-2.84 times bigger catalytic effect than imidazole. The catalytic effects of imidazole and triamine-copper(Ⅱ)-imidazolate complex were increased by an electron releasing substituent, meanwhile decreased by an electron-withdrawing substituent of imidazole ring. The triamine-copper(Ⅱ)-imidazolate which composed of two fused five-membered rings showed slightly more effective catalytic action than composed of one fused five-membered ring and one fused six-membered ring. This fact implies that the Cu(Ⅱ) complex containing tridentate ligand of five-membered ring is more stable than the complex containing tridentate ligand of six-membered ring. In contrast with a general acetal molecule, 4-nitorphenyl-x-D-glucopyranoside was readily hydorlyzed at high pH reaction media. A plausible mechanism for this observation is proposed.

사람 뇌척수액중 Transthyretin의 항산화작용

양성렬,최기오,박종근,류문희,홍석노,김수한,안봉환,이제혁,이민화 대한신경외과학회 1994 Journal of Korean neurosurgical society Vol.23 No.4

Protective effects of human cerebrospinal fluid antioxidants against enzyme inactivation caused by metal-catalyzed oxidation systems were investigated. When purified glutamine synthetase(GS) was incubated with human cerebrospinal fluid(CSF), the enzyme was progressively inactivated. Catalase and EDTA could inhibit the enzyme inactivation by 50-80%. Small-molecular(Mr< -10,000) fraction of CSF inactivated the exogenous GS, but large-molecular(Mr> -10,000) fraction did not. The GS inactivation by the small-molecular fraction was also markedly inhibited by catalase and EDTA. These results suggested that metal-catalyzed oxidation is involved in the GS inactivation by the small-molecular fraction of CSF. Dithiothreitol(DTT) was shown to inhibit almost completely the oxidative inactivation of GS by CSF. However, DTT inhibited only partially the oxidative inactivation of GS caused by small-molecular fraction of CSF. When large-molecular fraction of CSF was separated by anion-exchange HPLC chromatogrpahy, there was a peak of antioxidant activity inhibiting the small-molecular fraction-induced GS inactivation in the presence of DTT. The antioxidant activity was neutralized by monoclonal antibodies to transthyretin. Purified transthyretin was found to efficiently inhibit ascorbate/Cu^(2+)-induced GS inactivation in the presence of DTT. Uric acid and glucose did not show any protective effect on the GS inactivation in the same condition. The above results suggest that metal-catalyzed oxidation occurs normally in human CSF, and that transthyretin may play an important role as a CSF antioxidant in protecting proteins from metal-catalyzed oxidation.

과학 영재를 위한 캠프 운영과 교육 프로그램의 개발 준거

여상인,노석구,강호감,이희순,홍석인,송상헌,정동권 인천교육대학교 과학교육연구소 2003 과학교육논총 Vol.15 No.-

본 연구는 영재 프로그램과 그 운영의 적절성과 타당성을 판단하는데 기초 자료가 될 수 있는 준거를 추출하기 위한 연구이다. 과학캠프 활동 프로그램에 대한 학생들의 흥미와 유익성, 영재캠프 운영에 관련된 문항으로 구성된 설문지를 캠프에 참가한 학생과 그 학부모에게 실시하여 분석하였다. 영재 캠프에 참가한 학생은 직접 참여할 수 있으면서 지적 호기심을 자극하는 활동에 흥미를 느꼈고, 놀이 요소가 포함된 프로그램을 많이 선호하였다. 학생들이 모르거나, 중요하다고 생각하거나, 일상생활에 적용할 수 있는 과학 지식이나 원리를 배웠다고 인식하는 경우, 유익한 프로그램으로 인식하였다. 과학 영재 캠프의 운영에 있어서 많은 학생이 방학 중에 1주일 정도의 기간으로 합숙하는 프로그램 운영 방식을 선호하였다. 이러한 연구 결과를 토대로 본 연구에서는 캠프 활동 프로그램과 운영에 대한 몇 가지 시사점을 제안하였다. This study is to find out criteria and basic data to evaluate effectiveness and validity of program for gifted children in science. To this purpose, a questionnaire to investigate the perception of interest and usefulness for camp activities was administered to the gifted children registered to science camp. By analyzing their responses, we could conclude that the gifted children thought the activities, which stimulating their curiosity or providing opportunities to participate, to be interesting to them. They preferred the activities like a play or a game and considered that a useful activities should have something worth-learning. They and their parents preferred to stay in a camp for a week. Based on this research, we suggested some implications about academic camp program for gifted children in science.

9/11 테러와 미국의 정보공동체 변화

장노순,박수홍,조상태 한라대학교 2007 論文集 Vol.10 No.-

The emergence and broad spread of transnational threats since the collapse of the Soviet Union have emphasized the need of efficient intelligence agencies as well as military forces as means of national security. The attack of September 11, 2001 upon the United States brought on a drastic transformation of its domestic security policy and governmental structure. This study is aimed at exploring how the 9/11 attack has influenced America's intelligence community and how such an intelligence failure has changed the security policy. One of the biggest reforms is to establish the National Security Agency (NSA) that is designed to control and coordinate all members of the intelligence community. However, the adaptation of America's intelligence community to the current security environment is not sufficient to maintain its leadership in the global society from new threats such as terrorists. Agents with skill of foreign languages and local informants will play a key role of collecting and analyzing information concerning the adversary.

전자충돌이 Mo/Pd(100)계의 저에너지 전자회절 pattern에 미치는 영향

김홍직,신용상,노창완,진원배 東亞大學校附設基礎科學硏究所 1999 基礎科學硏究論文集 Vol.16 No.1

Mo 재질의 평판 위에 Pd(100) 결정시료를 놓고 3 keV의 Ar 이온선으로 동시에 bombardment 시킬때, Mo 원자들이 Pd(100)상에 증착 되는 현상을 발견하였다. 이렇게 증착된 Mo 원자들의 덮임율과 흡착구조, 그리고 이들 흡착구조들이 전자선 충격에 의해 받는 영향을 LEED와 AES를 이용하여 조사하였다. 흡착된 Mo 원자의 덮임율이 0.1일 때, Mo/Pd(100)로부터 어닐링(annealing) 온도 300℃와 500℃이상에서 각각 c(4×2)와 c(4×2)3+(√5×√5)R arctan 1/2 pattern이 관측되었다. 이들 pattern중 안정된 흡착구조인 (√5×√5)R arctan 1/2 는 3 keV의 전자선 충격에 의한 영향이 매우 적으나 불안정한 흡착구조인 c(4×2)는 민감하게 영향을 받고 있음을 알 수 있었다. Pd(100) sample was mounted on Mo plate in ultra high vacuum chamber, and both of Pd(100) sample and Mo plate were bombarded by 3 keV Ar ion beam. It was found that this bombardment gave rise to deposition of Mo atoms on Pd(100). The coverage and overlayer structure of Mo adatom, and an effect of the electron impact on this Mo/Pd(100) system were investigated by LEED and AES. When the coverage of Mo was 0.1, c(4×2) and c(4×2)+(√5×√5)R arctan 1/2 pattern were observed from this system at annealing temperature of 300℃ and above 500℃, respectively. When irradiating 3 keV electron beam on these surface structures, the c(4×2) corresponding to unstable overlayer structure from both LEED patterns was sensitively influenced but the (√5×√5)R arctan 1/2 not sensitively by 3 keV electron impact.

외과계 감염증에 대한 Sulperazon(Sulbactam/cefoperazone) 및 Cefoperazone의 임상효과 비교연구

박규주,노동영,김상준,권오중,정중기,홍인규 대한화학요법학회 1990 대한화학요법학회지 Vol.8 No.2

Despite recent advances in development of antibiotics and antiseptic techniques, infection still remains to be one of the major problems in the surgical field. Due to development of bacterial resistance to commonly used antibiotics, there is always a need to develop a new antimicrobial agent which would overcome such resistance. Sulperazon (Sulbactam/Cefoperazone) is a combination drug of potent β-lactamase inhigitor, sulbactam, and cefoperazone which has broad antibacterial spectrum, which was developed to combat against β-lactamase producing microorganisms. In an effort to evaluate the efficacy and safety of sulperazone, we have randomly divided 40 patients (12 with perforated appendicitis, 10 with peritionitis, 6 with GB empyema, 6 with periproctal abscess, 3 with wound infection, 1 liver abscess, 1 pancreatic abscess, and 1 acute cholangitis) into 2 groups (20 patients in each group). One group received daily dose of 2 to 3 grams of sulperazon and the other group received daily dose of 2 to 3 grams of cefoperazone. Following results were obtained : 1. Clinical effect of sulperazon was cure in 16 patients (80%), improvement in 3 patients (15%), compaired to cure in 14 patients (70%), improvement in 4 patients (20%) for the cefoperazone group. 2. Using disc diffusion method, sulperazon was sensitive to all of the isolated microorganisms except β-hemolytic streptococci, which was moderately sensitive. Cefoperazone was sensitive to only E. coli, Pseudomonas aeruginosa and Serratia. 3. Microbiological effect of sulperazon was eradication of offending microorganisms in 16 patients (80%), compared to 14 patients (70%) in Cefoperazone group. 4. Overall clinical efficacy of sulperazon was 95%, compared to 80% for cefoperazone. 5. Adverse effects due to sulperazon was nausea and diarrhea which occurred in 1 patient respectively. 2 patients receiving cefoperazone experienced diarrhea. It can be concluded that sulperazon is a safe and effective antibiotic agent which can be used in surgical infection patients.

cDNA array 방법을 이용한 망간에 노출된 흰쥐 뇌기저핵의 유전자발현 분석

이채관,노성민,문덕환,,김정호,손병철,김대환,이창희,김휘동,김정원,김종은,안진홍,이채언 大韓産業醫學會 2005 대한직업환경의학회지 Vol.17 No.4

Objectives: This study investigated the gene expression profile in basal ganglia of manganese-exposed rats based on cDNA array analysis. Methods: For cDNA array, 25 male Sprague-Dawley rats (250±25 g) were intraperitoneally injected with 25 ㎎/㎏ B. W./day of MnCl2 (0.3 ㎖) for 10 days. For dose-related gene expression analysis, rats were intraperitoneally injected with 0.2, 1.0, and 5.0 ㎎/㎏ B. W/day of MnCl2 for 10 days. Control rats were injected with an equal volume of saline. RNA samples were extracted from brain tissue and reverse-transcribed in the presence of [α^(32)P]-dATP. Membrane sets of the Atlas Rat 1.2 array Ⅱ and Toxicology array 1.2 kit (Clontech, Palo Alto, CA) were hybridized with cDNA probe sets. Northern blot hybridization method was employed to assess the dose-related gene expression. Results: Fifty-two genes showed significant changes in expression of more than two-fold. Twenty-eight were up-regulated and 24 were down-regulated in the manganese-exposed group compared to the control. Among the 52 genes, 28 genes including nuclear factor I-X1 (NF1-X1), neuroligin 2 and 3, mitochondrial stress-70 protein (MTHSP70), neurodegeneration-associated protein 1 (Neurodap 1), multidrug resistance protein (MDR), and endoplasmic reticulum stress protein 72 (ERP72), were reported for the first time related to the manganese-induced neurotoxic-metabolism in the rat basal ganglia. According to the dose-related gene expression analyses, MTHSP70, Neurodap 1 and ERP72 genes were up-regulated compared to the control even in the group exposed to low manganese dose ( 0.2 ㎎/㎏ B.W./day). Conclusions: Twenty-eight genes detected for the first time in this study were closely related to the manganese-induced neurotoxic-metabolism in the rat basal ganglia and further study of these genes can give some more useful information about the manganese metabolism.

생체용 Ti합금의 양극분극특성에 미치는 Zr 및 Pd의 영향

정종현,이길홍,최칠남,노학,백승남,이상열 대한치과기재학회 1999 대한치과재료학회지 Vol.26 No.2

The corrosion resistance of Ti-Zr-Pd-Cr alloys were investigated in order to reveal their possible use for new biomedical implant materials. Titanium alloys consisting of 10∼20%Zr, 0.0∼0.4%Pd and 0.15%Cr were prepared by vacuum arc-melting as alloying elements instead of using hardness Al and V in response to recent concerns about the long term safety of Ti-6%Al-4%V ELI alloys. The Ti-Zr-Pd-Cr alloys were heat-treated at 1000℃ for 2hrs under a vacuum atmosphere. The effect of Zr and Pd Ti alloys on the corrosion resistance for biomedical implant was investigating the anodic polarization curve at 37℃ in 5%HCI solution deaerated by high-purity N₂gas bubbling. The critical current density for passivation(I ) of Ti-Zr-Pd-Cr alloys didn't reveal markedly. Passive current density(I ) at 1.0V vs. SCE of this alloys decreased with increasing Zr in the contents from 10 to 20% and decreased with containing Pd in the range from 0.2 to 0.4%. Potential(E ) at 0.1A * m-² of this alloys increased with increasing Zr in the contents from 10 to 20% and increased with containing Pd in the range from 0.2 to 0.4%. For the Co-30%Cr-6%Mo alloy, passivity zone is narrow, and rapid increase of current density result from the low potential in comparison with Ti and Ti alloys. The corrosion resistance by the anodic polarization of Ti-20%Zr-0.2%Pd-0.15%Cr alloy was found to be superior to those of the Ti, Ti-6%Al-4%V alloy and Co-30%Cr-6%Mo alloy. The passive films formed on the Ti-20%Zr-0.2%Pd-0.15%Cr and Ti-6%Al-4%V alloys in the anodic polarization test consist mainly of TiO₂, Ti compound, ZrO₂, Al₂O₃and V₂O₃.

회전근 개 파열 관절중에서 시행한 역구형 관절 치환술 : 2례 보고

문영래,이상홍,노경환 朝鮮大學校 附設 醫學硏究所 2009 The Medical Journal of Chosun University Vol.34 No.1