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레이저 회절발법에 의한 네마틱상 MBBA의 비선형 광학성 동력학
윤보형,이일근,김성규 성균관대학교 기초과학연구소 1997 論文集 Vol.48 No.-
170㎛ 두께의 네마틱 MBBA film에 레이저 여기빔을 교차시켜 회절발을 형성시켰을 때 회절 신호를 시간적으로 추적하여 비선형 광학 동력학적 정보를 얻었다. 여기빔의 파장이 355nm이고 펄스의 세기가 10mJ/㎠일 때 회절신호의 시간적인 모양은 sub-ms, ms이 시간대에서 구분할 수 있는 4개 성분으로 구성되어 있다. 회절발의 간격이 8㎛일 때 가장 빠른 성분은 실험기기의 한계시간(~20ns)내에서 발생하고 약 10㎲시간으로 사라지는데 이는 계면의 열확산에 기인한다. 이 성분은 탐사빔의 편광에 크게 의존해서 나타난다. 네마틱상-등방상 상전이 지점에 접근하는 온도가 되면 이 편광의존성은 감소한다. 가장 약하고 느린 성분은 100ms의 시간대에서 관찰되어지는데 cis-MBBA의 질량확산이라 볼 수 있다. sub-ms 와 ms 시간대에서 회절신호의 지배적인 중간의 두 성분은 각각 지수함수적으로 증가하고 지수함수적으로 감소함을 보여준다. 두 성분의 원인은 각각 레이저 조사에 의한 온도변화로 인해 질서도의 파괴 및 회복, 레이저에 의해 형성된 광변형 상태에 의한 질서도의 파괴 및 회복에 기인한 것으로 판단된다. 온도가 상전이 점에 가까워지면 물질의 광학 비선형도는 다차회절이 눈으로도 관측될 정도로 증가한다. 다차회절신호를 휴리에 변환하여 회절발의 모양을 합성함으로써 주로 광변형상태의 존재가 다차회절의 원인, 즉 비이상적으로 높은 비선형 광학성의 중요한 원인으로 생각할 수 있다.
김윤철,이정우,김보영,강정아,임대승,이민수,김정희,성보영,최성준,성인환,전은석 충남대학교 의과대학 지역사회의학연구소 2000 충남의대잡지 Vol.27 No.1
Coronary stent implacement is known as an effective treatment in the intimal dissection after percutaneous transluminal coronary angioplasty and the prevention of restenosis. However, In-stent restenosis still remains a major concern in clinical stenting. The stents were placed in 103 patients from July 1996 to March 1999 and performed follow-up coronary angiograms in 59(57.3%) patients. To identify the clinical, angiographic and procedurerelated variables 'which predict late restenosis within the stented artery, 59 patients(58.3±9.9, M:F= 41:18) were studied. The clinical characteristics of the patients were stable angina in 23(39.0%), unstable angina in 14(23.7%), acute myocardial infarction in 21(35.6%) and old myocardial infarction in 1(1.7%). Coronary stenting was performed in 1 patient(1.7%) for primary lesion, 50 patients(84.7%) for suboptimal results after PTCA, 6 patients(10.2%) for bail-out procedure, and 2 patients(3.4%) for restenotic lesions. All patients were treated with aspirin and ticlopidinc. The follow-up angiograms were obtained at 7±4 months. The overall in-stent restenosis rate was 27.1%. The coronary angiographic findings were 32 single vessel(54.2%), 19 two vessel(32.2%) and 8 three vessel disease(13.6%). The angiographic morphological characteristics were type A in 33(55.9%), type B in 14(23.7%), type C in 12(20. 3%) cases. Variables of 16 patients with restenosis were compared with those of 43 patients without restenosis. Previously known predictors for in-stent restenosis were multiple stenting, stenting for restenotic lesions, residual stenosis after stenting, stenting for total occlusion lesions, reference diameter, balloon to vessel ratio, acute gain and minimal luminal diameter after procedure, design and characteristics of stents, ostial lesion of aorta, high pressure method for stenting, lesion length, diabetes mellitus, size of artheroma, saphenous vein grafts, ulcerlating lesions and calcified lesions. In this study, Reference diameter before stenting(2.43±0.54mm vs. 2.88±0.65mm, p=0.016) and balloon-to-artery ratio(1.28±0.26 vs. 1.11±0.18, p=0.006) were predictors for in-stent restenosis. 1) The overall in-stent restenosis rate was 27.1%. 2) In the analysis of predictors for in-stent restenosis, there was no significant differences in clinical, angiographic factors between group with restenosis and without restenosis. But, Only reference diameter before stenting and balloon-toartery ratio were predictors of late in-stent restenosis. In conclusion, stenting is effective revascularisation method for selected patients with ischemic heart disease, and to minimize in-stent restenosis rate, stent implanting is achieved in a large vessel on the basis of an artery-to-stnet ration of 1:1, if possible.
2-Amino-1-cyclopentene-1-dithiocarboxylate 유도체들의 전극 반응메카니즘
金映辰,金祐聖,沈允補,崔星洛 부산대학교 기초과학연구소 1990 부산대학교 기초과학연구소 연구논문집 Vol.10 No.-
N-methyl-2-amino-1-cyclopentene-1-dithiocarboxylic acid(N-CH₃acdc)와 2-amino-1-cyclopentene-1-dithiomethyl ester(S-Ch₃acdc)의 전기화학적 거동을 직류롤라로그래피, 순환전압전류법 및 조절전위 전기량법을 사용하여 dimethylformamide(DMF) 용매 중에서 조사하였다. N-CHacdc의 이합체는 +0.98V에서 2전자 산화반응을 거쳐 s가 한 원자 유리된 다섯원자 고리를 형성하는 전극반응이 일어남을 알았다. 그러나, S-CH₃acdc의 경우에 있어서는 N-CH₃acdc 화합물과는 달리 다섯원자 고리를 형성하지 않았으므로 N-CH₃acdc와는 다른 전극반응을 일으킴을 확인하였다. The electrochemical behavior of N-methyl-2-amino-1-cyclopotent-1-dithiocarboxylic acid (N-CH₃acdc) and 2-amino-1-cyclooptent-1-dithiomethyl ester (S-CH₃acdc) in DMF have been investigated by the use of polyargraphy, cyclic voltammetry and colometry. The dimer of N-CH₃acdc is further oxidized at +0.98 V via 2-electron process to produce free sulfur atom and cyclization product. The ring formation between two dithio group occurs along with the elimination of one sulfur atom. The elimination of sulfur atom occurs via two electron oxidation process at +0.98V vs. Ag/AgCl electrrode. However, the cyclization does not occur in the S-CH₃acdc.
한국인에서 혈소판 당단백 Ⅱb/Ⅲa 유전자 다형성과 관동맥 성형술 후 재 협착과의 관계
이민수,이정우,김보영,임대승,강정아,김정희,김윤철,성보영,최성준,성인환,전은석 충남대학교 의과대학 지역사회의학연구소 2000 충남의대잡지 Vol.27 No.2
Platelet aggregation is the final pathway of acute coronary syndrome such as acute myocardial infarction and unstable angina. Platelet glycoprotein IIb/IIIa is a membrane receptor for fibrinogen and yon Willebrand factor and it plays an important role in platelet aggregation and in the pathogenesis of acute coronary syndrome. It is known that polymorphism of the gene that encoding platelet glycoprotein IIb/IIIa(PI^A1/A2) is strongly related to acute coronary syndrome in Caucasian, but not in Koreans. We investigated relationship between platelet glycoprotein llb/Illa gene polymorphism and restenosis of coronary artery after angioplasty in Koreans. Total 371 patients(M=251. F=120) were enrolled. Angioplasty group comprised 143 patients who underwent coronary angioplasty, and in the angioplasty group, restenosis group comprised with the 65 patients who had restenotic lesion over 50% of luminal diameter in follow-up coronary angiography. Normal group comprised 153 patients who had no significant angiographic lesion and variant angina group comprised 75 patients who were positive in ergonovine test. Genomic DNA was extracted from peripheral arterial blood. To determine the frequency of P1^A1/A2 genotype, polymerase chain reaction(PCR) was done and the product was restricted with Mspl. 3%. agarrose gel electrophoresis showed restriction fragment length polymorphism. Clinical profile and risk factor were also reviewed. Among all 371 patients of study group, genotype of only one patients in restenosis group if is proven to be PI^A1/A2 heterozygote. All patients of normal study group, no restenosis group, and the other patients in restenosis group have an PI^A1 homozygote genotype. In our study, platelet glycoprotein IIb/Illa polymorphism has no relationship with restenosis of the coronary artery after angioplasty in Koreans. But the genotypic frequency of platelet glycoprotein IIb/IIIa gene polymorphism in Koreans is concordant with that of previous studies.
18세 남자 환자에서 좌주간지 혈전이 동반된 급성 심근 경색
윤성보 ( Seong Bo Yoon ),이상학 ( Sang Hak Lee ),박광혁 ( Kwang Hyuk Park ),한권우 ( Kweon Woo Han ),정재헌 ( Jae Hun Jung ),최승혁 ( Seung Hyuk Choi ),이남호 ( Nam Ho Lee ) 대한내과학회 2005 대한내과학회지 Vol.69 No.-
Acute myocardial infarction in the adolescence is unusual. Moreover, the prevalence of left main coronary artery stenosis is rare in this population. We describe a case of acute ST elevation myocardial infarction in an 18 year-old male. He did not have history of congenital heart disease or other traditional risk factors for premature coronary disease. He was mildy overweight and showed normal laboratory tests except low high-density lipoprotein cholesterol level and modestly elevated plasma homocysteine level. Coronary angiography revealed totally occluded left anterior descending artery and thrombus at the bifurcation of left main coronary artery. He underwent emergency coronary stenting at distal left main coronary artery and proximal left anterior descending artery. He was discharged without in-hospital cardiac event. (Korean J Med 69:S807-S811, 2005)
연구노트 : 3T3-L1 지방세포내 ROS 생성에 대한 천년초 열수 및 에탄올 추출물의 항산화 효과
윤보라 ( Bo Ra Yoon ),이영준 ( Young Jun Lee ),김선구 ( Sun Gu Kim ),장중영 ( Jung Young Jang ),이효구 ( Hyo Ku Lee ),이성갑 ( Seong Kap Rhee ),홍희도 ( Hee Do Hong ),최현선 ( Hyeon Son Choi ),이부용 ( Bo Yong Lee ),이옥환 ( Ok Hw 한국식품저장유통학회 ( 구 한국농산물저장유통학회 ) 2012 한국식품저장유통학회지 Vol.19 No.3
Recently, NADPH oxidase 4 (NOX4)-mediated generation of intracellular reactive oxygen species (ROS) was proposed to accelerate adipogenesis of 3T3-L1 cell. We have previously shown that Cheonnyuncho (Opuntia humifusa) extract significantly inhibited adipocyte differentiation via downregulation of PPARγ (peroxisome proliferator-activated receptor gamma) gene expression. In this study, we focused on the molecular mechanism(s) of NOX4, G6PDH (glucose-6-phosphate dehydrogenase) and antioxidant enzymes in anti-oxidative activities of 3T3-L1 adipocytes. Our results indicate that Cheonnyuncho extracts markedly inhibits ROS production during adipogenesis in 3T3-L1 cells. Cheonnyuncho extracts suppressed the mRNA expression of the pro-oxidant enzyme such as NOX4 and the NADPH-producing G6PDH enzyme. In addition, treatment with Cheonnyuncho extract was found to upregulate mRNA levels of antioxidant enzymes such as Mn-SOD (manganese-superoxide dismutase), Cu/Zn-SOD (copper/zinc-SOD), glutathione peroxidase (GPx), glutathion reductase (GR), and catalase, all of which are important for endogenous antioxidant responses. These data suggest that Cheonnyuncho extract may be effective in preventing the rise of oxidative stress during adipocyte differentiation through mechanism(s) that involves direct down regulation of NOX4 and G6PDH gene expression or via upregulation of endogenous antioxidant responses.