Characterizations of Modified Silica Nanoparticles(I)

Min, Seong-Kee,Park, Chan-Young,Lee, Won-Ki,Seul, Soo-Duk Materials Research Society of Korea 2012 한국재료학회지 Vol.22 No.6

(3-mercaptopropyl)trimethoxysilane (MPTMS) was used as a silylation agent, and modified silica nanoparticles were prepared by solution polymerization. 2.0 g of silica nanoparticles, 150 ml of toluene, and 20 ml of MPTMS were put into a 300 ml flask, and these mixtures were dispersed with ultrasonic vibration for 60 min. 0.2 g of hydroquinone as an inhibitor and 1 to 2 drops of 2,6-dimethylpyridine as a catalyst were added into the mixture. The mixture was then stirred with a magnetic stirrer for 8 hrs. at room temperature. After the reaction, the mixture was centrifuged for 1 hr. at 6000rpm. After precipitation, 150 ml of ethanol was added, and ultrasonic vibration was applied for 30 min. After the ultrasonic vibration, centrifugation was carried out again for 1 hr. at 6000rpm. Organo-modification of silica nanoparticles with a ${\gamma}$-methacryloxypropyl functional group was successfully achieved by solution polymerization in the ethanol solution. The characteristics of the ${\gamma}$-mercaptopropyl modified silica nanoparticles (MPSN) were examined using X-ray photoelectron spectroscopy (XPS, THERMO VG SCIENTIFIC, MultiLab 2000), a laser scattering system (LSS, TOPCON Co., GLS-1000), Fourier transform infrared spectroscopy (FTIR, JASCO INTERNATIONL CO., FT/IR-4200), scanning electron microscopy (SEM, HITACHI, S-2400), an elemental analysis (EA, Elementar, Vario macro/micro) and a thermogravimetric analysis (TGA, Perkin Elmer, TGA 7, Pyris 1). From the analysis results, the content of the methacryloxypropyl group was 0.98 mmol/g and the conversion rate of acrylamide monomer was 93%. SEM analysis results showed that the organo-modification of ultra-fine particles effectively prevented their agglomeration and improved their dispensability.

Lumbricus rubellus에 존재하는 Lumbrokinase의 Ubiquitin-conjugate 분해활성에 관한 연구

우기민,이상한,조만희 순천향의학연구소 2004 Journal of Soonchunhyang Medical Science Vol.10 No.1

본 연구에서 Lumbricus rubellus에 존재하는 강력한 fibrinolytic 효소인 Lumbrokinse들을 여러 크로마토그래피법을 이용하여 부분정제하고 그들의 생화학적 성질들을 조사하고 비교하였다. L. rubellus의 단백질 추출물은 fibrinogen, lactalbumin, BSA, casein 등 다양한 단백질들을 분해하는 활성을 가졌으며, 그들의 활성은 poly-lysine같은 poly-cation들에 의하여 활성화되었다. 또한 이러한 활성화 정도는 poly-cation들의 길이에 의존적이며 poly-lysine의 경우 이성체에 상관없이 모두 활성화시켰다. DEAE-Sepharose를 통하여 확인된 3 종류의 분해활성으로부터 2 종류의 서로 다른 Lumbrokinse들을 Phenyl-Sepharose, Superose-12 크로마토그래피들을 통하여 부분정제하여 E-I, E-III라고 명명하였다. SDS-PAGE와 gel filtration을 시행하였을 때 그들은 각각 33 kD과 38 kDa의 폴리펩타이드로 구성된 단일체로 규명되었다. E-I의 fibrinogen을 분해하는 특이적 활성은 poly-lysine이 없을 경우 3.75 ng hydrolysis/ng enzyme/20 min으로 상대적으로 낮았으나 poly-lysine이 첨가될 경우 75 ng hydrolysis/ng enzyme/20 min로 활성이 20배가량 증가하였다. 반면 E-III는 poly-lysine이 없을 경우 20 ng hydrolysis/ng enzyme/20 min으로 상대적으로 높았지만 poly-lysine의 첨가시 129 ng hydrolysis/ng enzyme/20 min로 약 6.5배의 증가를 보였다. 0.2 M의 KCI은 poly-lysine에 의한 fibrinogen 분해활성을 강하게 억제하였으며 펩타이드 분해활성은 E-I와 E-III가 서로 다른 영향을 받았다. E-III는 poly-lysine에 의해 증가된 활성이 억제받는 반면, E-I는 오히려 펩타이드 분해활성이 KCI에 의하여 10배가량 증가되었다. 이러한 상반된 결과는 두 효소가 서로 다른 분해기작과 조절기작을 가짐을 의미한다. 정제된 E-I와 E-III는 놀랍게도 ubiquitin이 결합된 일련의 단백질들을 분해하였으며, 이 활성도 또한 poly-lysine에 의하여 증가되었다. 또한 ubiquitin-conjugate의 분해활성은 PMSF에 의하여 억제받으므로 serine계의 단백질 분해효소이며 IAA에 의하여 억제받지 않으므로 활성화 부위에 sulfide 기가 관여하지 않는 것으로 판명되었다. 또한 fibrinogen의 분해에서와 같이 이들의 활성도 KCI에 의해 억제되었다. Ubiquitin-conjugate들은 분해된 후 자유 ubiquitin이 반응산물로 나타났으므로 E-I과 E-III는 포유동물들에 존재하는 ubiquitin C-terminal hydrolase (UCH)의 새로운 종류이거나 26S proteasome을 대신할 수 있는 또 다른 형태의 단백질 분해효소일 가능성을 제공해준다.

조직 구성원의 비윤리적 행위에 대한 도덕적 용인의 조절효과 분석

민기 ( Min¸ Kee ),박철민 ( Park¸ Cheol-min ) 대한정치학회 2021 大韓政治學會報 Vol.29 No.3

행정서비스의 수준은 행정의 주체인 공무원들의 의식 여하에 따라서 좌우됨은 재론을 요하지 않는다. 선후진국을 통틀어 정도 차이는 있어도 관료들은 공복으로서 사명감이 부족할 뿐 아니라 국가에 따라서 부정과 부패의 온상으로 여겨지기도 한다. 본 연구는 공무원들의 비윤리적 행위의 억제는 행정 능률성에 직결된다는 판단하에, 부산 지역 근무 공무원들을 대상으로 비윤리적 행위에 영향을 미치는 변수, 크기 및 조절 변인 분석에 목적을 둔다. 그간 조직 성과에 영향을 미치는 변수들에 대해서는 다수 연구들이 이루어져 왔지만, 처벌, 비윤리적 행위 등 부정적인 행동 변수들간 관계에 대해서는 그다지 많은 연구가 이루어지고 있지는 않다. 이 연구는 현재의 통제 지향적 관리체제하에서 그 동안 경시되어 온 비윤리적 행위 등 부정적인 행동을 억제하는 것이 조직 성과 제고 나아가 조직 혁신의 중요 과제라는 가정하에, 변인들간의 관계를 실증 분석하는 데 목적을 두었다. 분석 결과, 원인변수인 처벌 및 동료는 도덕적 용인과 비윤리적 행위의 중요 영향 변인의 역할을 수행하는 것으로 나타났다. 동시에 도덕적 용인은 원인변수인 처벌 및 동료를 자극하여 비윤리적 행위를 더욱 감소시키는 것으로 나타나서 이들 사이에서 조절변수로서 기능하는 것이 확인되었다. 본 연구는 외생변인들을 처벌, 동료에 한정한 한계는 있지만, 구성 변인들이 요인분석을 통해서 체계적으로 구성되었으며, 비윤리적 행위에 미치는 영향 변인들을 실증분석을 통해서 규명함으로써 분석 결과의 합리화를 추구하고 있는 점에서 연구 가치가 있는 것으로 본다. Nowdays, moral approbation and unethical behavior are expected to negatively related each other, and effect many highly valued organization outcomes in various work contexts respectively. Many previous studies support the belief by suggesting that unfavorable unethical behavior is negatively concerned with organization effectiveness as well as organization competitiveness, members’ job satisfaction, and quality of life. In spite of the discording role of the unethical behavior and moral approbation on organization outcomes, the relative contribution of the two concepts to organization outcomes has not been fully tested yet. Suggesting the relationship between antecedents and outcome variable, ie, punishment, colleague, moral approbation, and unethical behavior, therefore, this study analyzed the relationship between the constructs of over 238 public employees working in Busan City of Korea. Findings based on the moderating regression analysis supported the significantly negative impact between antecedents(punishment, colleague), and unethical behavior with moral approbation as a moderating variable.

우울증 환자 치료에 있어서 Tianeptine과 Sertraline의 효과와 안전성 비교

이민수,강성민,기백석,연병길,오병훈,이철,채정민,백인호 大韓神經精神醫學會 2001 신경정신의학 Vol.40 No.2

연구목적: 주요 우울증의 치료에 있어서 티아넵틴과 써트랄린의 임상적 효과와 안정성을 비교하기 위하여 연구를 시행하였다. 방법: DSM-IV 진단 기준에 의거하여 주요 우울증의 진단기준에 부합되고 17항목 해밀턴 우울척도 점수가 14점 이상인 환자를 대상으로 하였다. 총 40명의 환자를 무작위적 방식에 따라 티아넵틴 치료군과 써트랄린 치료군으로 분류하였다. 선탠된 환자에서 다른 항우울제를 복용하고 있는 경우 7일 이상의 약물 배설기간을 가진 후 티아넵틴과 써트랄린을 각각 6주간 투여하였으며, 기준점, 1주후, 2주 후, 4주 후, 6주 후에 HAM-D, MADRS, 그리고 CGI, COVI 등을 사용하여 평가하였다. 본 연구기간 중 발생된 모든 부작용은 부작용의 발생 및 소실 시기, 심한 정도, 발생 빈도, 관련 조치 및 결과에 대하여 증례기록서에 기록하도록 하였다. 결과: 30명(티아넵틴군 15명 ; 써트랄린군 15명)이 6주간의 연구를 완결하였고 티아넵틴 치료군에서는 1일 37.5mg을 투여하였으며 써트랄린군에서는 1일 평균 64.0±22.5mg을 투여하였다. 본 연구 결과 HAM-D, MADRS, CGI 상에서 두 군 모두에서 치료 1주 후부터 유의한 감소를 나타내었으며 이는 2주 후, 4주 후, 6주 후에도 지속적인 감소를 보였고 두 군간에 항우울 효과의 차이는 없었다. 활력징후, 일반 혈액학, 생화학, 심전도 검사 등에서는 두 군 모두 유의한 변화는 없었다. 티아넵틴과 관련된 부작용으로 흔히 보고한 증상은 오심(33.3%), 복부 불쾌감(26.7%), 구강 건조(20.0%), 두통(13.3%)등 이었고 써트랄린 치료군에서는 구강 건조(53.3%), 두통(46.7%), 오심(33.3%), 그리고 식욕 부진(33.3%)등으로 티아넵틴군에서 보다 적은 발현빈도를 보였다. 결론: 티아넵틴은 우울증의 치료에 있어서 효과적이고, 내약성이 우수한, 안전한 항우울제이다. Objective: This study was designed to evaluate the efficacy and safety of tianeptine and sertraline in the treatment of patients with depression. Method: The study was done on the patients with major depression diagnosed by DSM-IV, who had aHamilton Rating Scale for Depression(HAM-D) score ≥ 14 on the first 17 items of the HAM-D. A total of 40 patients were randomly assigned to tianeptine group and sertraline group. Tianeptine and sertraline were prescribed to each group. 6 weeks of each medication was carried out after 7 days of drug excretion period. Evaluation using 17 item HAM-D, Montgomery and Åsberg Depression Rating Scale(MADRS), Clinical Global Impression Scale (CGI), and Covi Scale was done on the baseline and after 1 week, 2 weeks, 4 weeks, and 6 weeks. Regrding all side effects that had occurred during the period of our study such as their developed/disappeaed time, severitien, incidences, managements and results have been recorded. Results: A total of 30 patients(tianeptine group 15 ; sertraline froup 15) finished the 6 weeks of research. 37.5mg of the daily dose was regularly prescribed to the tianeptine group, the average amount of 64.0±22.5mg of the final daily dose was prescribed to the sertraline group. Total 17 item HAM-D scores, total points of MADRS and CGI showed significant decrease after 1 week in each treatment froup and continous decrease after 2, 4 and 6 weeks ; and no difference was found between tianeptine group and sertaline group in the antidepressant efficacy. Also there were no significant changes in vital sign, CBC, chemistry, and EKG in each treatment group. The common reported side effects of tianeptine were nausea(33.3%), epigastic distress(26.7%), dry mouth(20.0%), headache(13.3%) and those of sertraline were dry mouth (53.3%), headache(46.7%), nausea(33.3%), anorexia(33.3%). Conclusion: According to the results, tianeptine was effective in improvement of depressive symptoms and was well tolerated and safe in patients with depression.

Vanadate가 사람의 제대혈관의 장력에 미치는 효과

김민경,김기순,이경로 建國大學校基礎科學硏究所 1998 理學論集 Vol.23 No.-

혈관작용성 물질의 연구에 이상적이라고 알려진 제대혈관의 장력에 미치는 vanadate의 효과와 그 작용기작을 규명하기 위하여 실험하였다. Vanadate는 사람의 제대정맥과 동맥 모두에서 농도의존적인 수축을 일으켰으며, 모든 농도에서 제대정맥이 제대동맥보다 더 큰 수축반응을 나타내었고, Methylene blue ( )를 혈관 절편에 전처리하거나 화학적으로 제대혈관을 탈내피 시킨 후 (saponin 0.03㎎/ml, 45min) verapamil ( )으로 전처리한 경우 vanadate의 수축반응은 제대정맥과 동맥 모두에서 유의한 차이가 없었으며, Indomethacin ( )으로 혈관 단편을 전처리한 후에는 vanadate에 의한 수축반응은 제대정맥과 동맥 모두에서 현저히 억제 (각각 97.6±0.02%, 97.3±0.01%)되었고 제대혈관 절편을 OKY046 ( )으로 전처리시킨 후 vanadate,의 수축 효과를 관찰한 결과 전처리 전과 유의한 반응의 차이를 볼 수 없었다. 사람의 제대혈관에서 vanadate에 의해 유발된 수축은 내피세포 비의존성 수축으로 제대동맥보다 정맥에서 수축 반응이 더 컷으며 ,vanadate에 의한 수축은 TXA₂가 아닌 prostanoid계의 다른 수축 물질에 의해 일어남을 알 수 있었다. Vanadium is a trace element essential for the normal development and growth of the human and animals. Under physiological conditions, it is present in small concentrations in serum and tissues of the different animals. This anion is able to inhibit ATPase and ATPase of different tissues, including the cardiac and vascular smooth muscle. These enzymes play an important role in the regulation of the vascular tone. In fact, it was recently reported that vanadate induced contractions of the vascular and non vascular smooth muscles. On the other hand, human umbilical vessels are known to be ideal for the study of vasoactive substances because of poor innervation of autonomic nerves to these vessels. The aim of present study was to investigate effect of vanadate on the vascular tension of the isolated human umbilical vein (HUV) and artery (HUA) obtained from full-term deliveries after cesarean section and to elucidate the mechanism of these vanadate-induced vascular response. Vanadate ( ) induced concentration-dependent contraction of HUV and HUA preparations. At all concentrations, contracting effect of vanadate was greater in vein than artery. Pretreatment with methylene blue ( ), soluble guanylate cyclase inhibitor and verapamil ( ), L-type channel blocker, did not affect vanadate-induced contractions of umbilical vessels. After chemical denudation with saponin (0.03㎎/ml, 45min), the contractile response to vanadate was not changed. To test whether prostanoid is related to this contraction, vascular preparations were pretreated with indomethacin ( ), cyclooxygenase inhibitor. Indomethacin suppressed the contracile response by 97.6±0.02% in the umbilical vein and by 97.3±0.01% in the umbilical artery. In both types of preparations, vanadate-induced contractions were not altered by OKY046( ), TXA₂(thromboxan A₂) inhibitor. These results suggest that vanadate produces contracions both in the isolated HUV and HUA, and that the vanadate-induced contractions are mediated, at least in part, through prostanoids other than TXA₂.

Comparison of Bradykinin- and Platelet-Derived Growth Factor-Induced Phosphoinositide Turnover in NIH 3T3 Cells

Lee, Kee-Ho,Ryu, Yong-Wun,Yoo, Young-Do,Bai, Dong-Hoon,Yu, Ju-Hyun,Kim, Chang-Min Korean Society for Biochemistry and Molecular Biol 1996 Journal of biochemistry and molecular biology Vol.29 No.6

Phosphoinositide turnover in response to platelet-derived growth factor, epidermal growth factor, and bradykinin was evaluated in NIH 3T3 cells. Platelet-derived growth factor and bradykinin induced a significant increase in incorporation of $^{32}P$ into phosphatidylinositol (PI), phosphatidylinositol 4-monophosphate (PIP), and phosphatidylinositol 4.5-bisphosphate ($PIP_2$) in serum-starved NIH 3T3 cells. However, epidermal growth factor increased incorporation of $^{32}P$ into these phosphoinositides by only a small amount. Stimulation with platelet-derived growth factor, not bradykinin, caused a rapid elevation of PI and PIP kinase activities that were maximally activated within 10 min. The maximal levels of their elevation in cells with plateletderived growth factor stimulation were 3.2-fold for PI kinase, and 2.1-fold for PIP kinase. Short term pretreatment of NIH 3T3 cells with phorbol 12-myristate 13-acetate, activator of protein kinase C. caused an approximately 60% decrease in platelet-derived growth factor-induced PI kinase activities, indicating the feedback regulation of phosphoinositide turnover by protein kinase C. These results suggest that although the enhancement of phosphoinositide turnover is a rapidly occurring response in platelet-derived growth factor- or bradykinin-stimulated NIH 3T3 cells, phosphoinositide kinases may be associated with initial signal transduction pathway relevant to platelet-derived growth factor but not to bradykinin.

Comparison of Bradykinin - and Platelet - Derived Growth Factor - Induced Phosphoinositide Turnover in NIH 3T3 Cells

Kim, Chang Min,BAI, DONG HOON,Yu, Ju Hyun,Lee, Kee Ho,Ryu, Yong Wun,Yoo, Young Do 생화학분자생물학회 1982 BMB Reports Vol.29 No.6

Phosphoinositide turnover in response to platelet-derived growth factor, epidermal growth factor, and bradykinin was evaluated in NIH 3T3 cells. Platelet-derived growth factor and bradykinin induced a significant increase in incorporation of ^(32)P into phosphatidylinositol (PI), phosphatidylinositol 4-monophosphate (PIP), and phosphatidylinositol 4,5-bisphosphate (PIP₂) in serum-starved NIH 3T3 cells. However, epidermal growth factor increased incorporation of BHP into these phosphoinositides by only a small amount. Stimulation with platelet-derived growth factor, not bradykinin, caused a rapid elevation of PI and PIP kinase activities that were maximally activated within 10 min. The maximal levels of their elevation in cells with plateletderived growth factor stimulation were 3.2-fold for PI kinase, and 2.1-fold for PIP kinase. Short term pretreatment of NIH 3T3 cells with phorbol 12-myristate 13-acetate, activator of protein kinase C, caused an approximately 60% decrease in platelet-derived growth factor-induced PI kinase activities, indicating the feedback regulation of phosphoinositide turnover by protein kinase C. These results suggest that although the enhancement of phosphoinositide turnover is a rapidly occurring response in platelet-derived growth factor- or bradykinin-stimulated NIH 3T3 cells, phosphoinositide kinases may be associated with initial signal transduction pathway relevant to platelet-derived growth factor but not to bradykinin.

Cytoprotective Effect of Hispidin Against Hyperglycemia Induced Oxidative Cell Damage on Mouse Insulin Producing Cells(MIN6)

Jae Soon Jang,Min Kyoung Min,Eock Kee Hong 한국생물공학회 2007 한국생물공학회 학술대회 Vol.2007 No.10

Simulated Moving Bed를 이용한 Bupivacaine 키랄분리 : (1) Preparative Chromatography를 이용한 기본조건 결정 (1) Optical Separation Conditions for Preparative Chromatography

윤지연,이중기,서성섭,최민호,박태진 한국화학공학회 2003 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.41 No.6

Racemate Bupivacaine의 키랄분리를 위한 크로마토그래피의 최적분리조건을 조사하였다. Kromasii^(�) 키랄고정상에서 최적이동상조성 성분은 n-hexane/2-propanol/acetic acid/triethylamine, 99/1/0.3/0.05(vol.%)이였다. 이동상 조성성분인 2-propanol의 부피비가 증가할수록 체류시간과 분리도가 동시에 감소되었다. 이동상 성분 중에서 미량으로 존재하는 triethylamine이 증가할수록 피크의 sharpness가 증가하고 체류시간 역시 감소하였다. 또한, acetic acid가 없으면, 크로마토그래피 광학분할이 불가능하였으며 부피 0.3%에서 분리도가 가장 높음을 확인할 수 있었다. 한편, 키랄의약품의 대량분리방법중의 하나인 SMB(simulated moving bed)크로마토그래피 시스템(직경 1.0cm×10cm×8개 칼럼으로 구성)의 최적분리조건을 전산모사에 의해 구하였으며, 이를 실험으로 확인하였다. 그 결과 switching time 15분, feed의 유량 0.1 ml/min, desorbent 0.86 ml/min, raffinate 0.3 ml/min, extract 0.66 ml/min, recycle 1.0 ml/min일 때 100% 순도의 R-form과 S-form을 얻을 수 있었으며, 실험치와 전산모사치간의 오차는 ??2%이내였다. The chiral separation of racemate Bupivacaine was carried out to find the optimum condition for chromatographic system. The optimum species and composition for mobile phase were n-hexane/2-propanol/acetic acid/triethylamine, 99/1/0.3/0.05(vol.%) in case Kromasil� chiral stationary phase was employed. The retention time and resolution decreased with the increase in the ratio of 2-propanol in the mobile phase. The sharpness of peak and retention time decreased, as the content of triethylamine increased. Without the existence of acetic acid, the chromatographic separation didn't occur, and the resolution was the highest at the acetic acid volume ratio of 0.3%. The optimum condition of SMB (simulated moving bed) was determined by simulation and its results was compared with exprimental data from lab-scale SMB (10 mm 1D×8 ea). Rased on the SMB simulation and experimental results, 100% purity of R and S Bupivacaine were obtained and the error between the calculated and experimental value was within ±2%.

간질환환자의 위내용물 배출시간에 관한 연구

함준수(Joon Soo Hahm),이동후(Dong Hoo Lee),박경남(Kyung Nam Park),이민호(Min Ho Lee),이종철(Jong Chul Rhee),기춘석(Choon Suck Kee),유대현(Dae Hyun Yoo) 대한소화기학회 1989 대한소화기학회지 Vol.21 No.2

N/A Gastric emptying time(GET) is influenced by several factors, such as neura), hormonal and composi- tion and physiochemical properties of food. The patients with delayed GET have some upper gastrointestinal symptoms such as recurrent nausea, vomiting, postprandia! Bloating, anorexia, and iveight loss. And also, almost of acute hepatitis and a part of chronic ]iver disease patients have similar symptoms of the patients with delayed GET. Therefore We performed GET measurement in liver disease patients to identify the relationship between nonspecific upper gastrointestinal symp- toms and gastric emptying function. The resu]ts are as followings; 1) Total ]iver disease patients are 28 in number, composed of acute hepatitis 3, chronic hepatitis 18, liver cirrhosis 7. 2) The GET(T1/2) of liver disease patients was delayed significantly than that of the normal volunteers. (Mean+SE;120.8+6.6 vs 89.4+5.9 mins.) 3) The GET of the symptomatic patients (N = 20 ) ivas 128.3+6.8 mins (Mean+SE), and that of the asymptomatic patients (N =8) was 101.8+13.2 mins. The symptomatic patients have delayed GET in 10 patients and asymptomatic patients have delayed GET in 3. 4) The GET of the patients who have elevated serum transaminase level higher than twice of normal is delayed significantly than that of the patients who have serum transaminase level lower than twice of normal. (Mean+SE; 143.4+2.6 vs 110.0+7.4 mins.)