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        아세틸 콜린 유발 검사시 허혈성 심전도 변화와 흉통의 발생이 내피세포 기능장애에 미치는 영향

        최철웅(Cheol Ung Choi),나승운(Seung-Woon Rha),김선원(Sun Won Kim),나진오(Jin Oh Na),임홍의(Hong Euy Lim),김진원(Jin Won Kim),김응주(Eung Ju Kim),한성우(Seong Woo Han),박창규(Chang Gyu Park),서홍석(Hong Seog Seo),오동주(Dong Joo Oh) 대한임상노인의학회 2010 대한임상노인의학회지 Vol.11 No.4

        연구배경: 아세틸 콜린 유발 검사시 발생하는 흉통과 허혈성 심전도 변화가 아세틸 콜린에 의해 발생하는 관상동맥의 내피세포 기능에 어떤 영향을 주는지 알아보고자 했다. 방법: 흉통으로 내원하여 관상동맥 조영술과 아세틸 콜린 유발검사를 시행받은 1,085명의 환자를 대상으로 하였다. 아세틸 콜린 유발 검사를 하는 동안 허혈성 심전도 변화 및 흉통의 발생 유무에 따른 관상동맥 내피세포 기능의 특징을 비교하였다. 결과: 539명의 환자에서 아세틸 콜린 검사시 내피세포 기능 장애가 발생 하였다. 허혈성 심전도 변화가 있었던 그룹이 심전도 변화가 없었던 그룹보다 흉통이 더 많았고(78.1% vs. 60.8%, P=0.007), 관상동맥 조영술상 다발성 관상동맥 경련이 빈번하였고(59.4% vs. 40.6%, P=0.004), 관상동맥의 경련 정도도 더 심하였다(64.1% vs. 46.5%, P=0.006). 흉통이 있었던 그룹이 흉통이 없었던 그룹보다 허혈성 심전도 변화의 빈도가 더 높았다(14.7% vs. 7.5%, P=0.007). 또한 흉통이 있었던 그룹이 관상동맥 경련이 다발성으로 발생하는 경우가 많았고 (50.7% vs. 29.5%, P<0.001), 미만성으로 발생하는 경우가 많았고(87.1% vs. 75%, P<0.001), 관상동맥의 경련의 정도도 더 심하였다(51.6% vs. 43.5%, P=0.041). 결론: 아세틸 콜린 유발검사시 발생하는 허혈성 심전도 변화와 흉통은 관상동맥 경련의 정도와 경련이 발생하는 관상동맥 개수와 연관이 있다. Background: ECG changes and chest pain during acetylcholine (Ach) provocation tests may constitute important clinical parameters for Ach-induced endothelial dysfunction. We investigated the association between ischemic ECG changes and chest pain during the Ach-provocation test and angiographic characteristics of Ach-induced endothelial dysfunction. Methods: A total of 1,085 patients with anginal symptoms underwent diagnostic coronary angiography (CAG) and Ach-provocation tests. We compared angiographic characteristics of Ach-induced endothelial dysfunction according to the presence of ECG change and chest pain. Results: A total of 539 patients experienced Ach-induced endothelial dysfunction. Patients who experienced ECG change group suffered more frequent chest pain (78.1% vs. 60.8%, P=0.007), angiographically more frequent multiple coronary artery spasm (59.4% vs. 40.6%, P=0.004), and more severe coronary artery spasm (64.1% vs. 46.5%, P=0.006) than patients without ECG change. However, there was no difference in the length of endothelial dysfunction between the groups. The incidence of ischemic ECG changes in patients with chest pain was higher than in patients without chest pain (14.7% vs. 7.5%, P=0.007). Patients who experienced chest pain more often experienced multiple (50.7% vs. 29.5%, P<0.001), diffuse (87.1% vs. 75%, P<0.001), and severe coronary artery spasm (51.6% vs. 43.5%, P=0.041) than patients without chest pain. Conclusion: Ischemic ECG changes and chest pain during the Ach-provocation test are associated with multi-vessel involvement and severe coronary artery spasm. Chest pain is associated with the length of endothelial dysfunction, but ischemic ECG change is not.

      • Projections of summertime ozone concentration over East Asia under multiple IPCC SRES emission scenarios

        Lee, Jae-Bum,Cha, Jun-Seok,Hong, Sung-Chul,Choi, Jin-Young,Myoung, Ji-Su,Park, Rokjin J.,Woo, Jung-Hun,Ho, Changhoi,Han, Jin-Seok,Song, Chang-Keun Elsevier 2015 Atmospheric environment Vol.106 No.-

        <P><B>Abstract</B></P> <P>We have developed the Integrated Climate and Air Quality Modeling System (ICAMS) through the one-way nesting of global–regional models to examine the changes in the surface ozone concentrations over East Asia under future climate scenarios. Model simulations have been conducted for the present period of 1996–2005 to evaluate the performance of ICAMS. The simulated surface ozone concentrations reproduced the observed monthly mean concentrations at sites in East Asia with high R<SUP>2</SUP> values (0.4–0.9), indicating a successful simulation to capture both spatial and temporal variability. We then performed several model simulations with the six IPCC SRES scenarios (A2, A1B, A1FI, A1T, B1, and B2) for the next three periods, 2016–2025 (the 2020s), 2046–2055 (the 2050s), and 2091–2100 (the 2090s). The model results show that the projected changes of the annual daily mean maximum eight-hour (DM8H) surface ozone concentrations in summertime for East Asia are in the range of 2–8 ppb, −3 to 8 ppb, and −7 to 9 ppb for the 2020s, the 2050s, and the 2090s, respectively, and are primarily determined based on the emission changes of NO<SUB>x</SUB> and NMVOC. The maximum increases in the annual DM8H surface ozone and high-ozone events occur in the 2020s for all scenarios except for A2, implying that the air quality over East Asia is likely to get worse in the near future period (the 2020s) than in the far future periods (the 2050s and the 2090s). The changes in the future environment based on IPCC SRES scenarios would also influence the change in the occurrences of high-concentrations events more greatly than that of the annual DM8H surface ozone concentrations. Sensitivity simulations show that the emissions increase is the key factor in determining future regional surface ozone concentrations in the case of a developing country, China, whereas a developed country, Japan would be influenced more greatly by effects of the regional climate change than the increase in emissions.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Change in ozone level is determined by the combination of NO<SUB>x</SUB> and NMVOC emissions. </LI> <LI> Ozone level over East Asia would get worse in the near future (the 2020s) than far future. </LI> <LI> A high-concentration event generally increases and more frequently occurs in the future. </LI> <LI> Change in ozone air quality in a developing country depends more on emissions change. </LI> <LI> Change in ozone air quality in a developed country depends more on climate change. </LI> </UL> </P>

      • 사이클링 선수의 슬관절각에 따른 하지동작의 운동학적 분석

        류창엽,최성진,박종진,강순용 한국운동역학회 2001 한국운동역학회지 Vol.11 No.3

        This study set out to evaluate the appropriateness of the height of a cycle saddle which was usually set based on a cyclist's experience and simple judgment. For this purpose, there was aroused a need to study what a cyclist's leg movements were according to the knee joint angle, that is, to study how a cyclist's leg joint angles and angular velocity would change at each pedaling. Seven male college cyclists were selected, and their pedaling movements were divided into four phases. The images were taped at 60fields/sec, using two video cameras. The KWON 3D 2.1 program was adopted to calculate and synchronize the 3D coordinates values which were calculated with DLT(Direct Liner Transformation), in order to analyze kinematical factors. The results were as follows: 1) There was found no difference between foot joint angles according to changes of knee joint angles in each phase. But it became clear that Phase 1 and 2 where the foot angle got bigger were the area where the foot joint was expanded and that Phase 3 and 4 where the foot angle got smaller were the area where the foot joint was bent. Accordingly, the area which gives a great indirect impact to the changes of foot joint angles is considered to be the first part of Phase 3 at which point the cycle of pedaling starts. 2) In terms of the difference of foot joint angular velocity according to knee joint angles, there was found a relatively stable deceleration in the decelerating area(Phase 3 and 4) while you could detect faster changes in the acceleration area(Phase 1 and 2) than in the decelerating area. 3) The changes in the angle difference of knee joints according to each knee joint angle showed almost similar patterns for every knee joint. But the patterns had the graph model of the opposite shape to that of the angle difference of foot joints. 4) The research went on to see what kind of difference the knee joint angle made as knee joint angular velocity changed. The changes were unlike the foot joint angular velocity and thus showed relatively slow deceleration and acceleration. And the higher the saddle was set, the bigger the difference of the angular velocity was. 5) The difference of hip joint angles according to knee joint angles made a graph pattern which showed no big correlation with the height of a saddle. 6) In considering how hip joint angular velocity would change according to knee joint angles, the higher a saddle was set, the bigger angular velocity was found in Phase 1 and 2, the area of joint expansion and the smaller angular velocity in Phase 3 and 4, the area of joint bending. Comparisons and analysis were made based on the results above mentioned. The conclusion was that the lower a saddle which was one of the three experiment conditions was set, the smoother the pedaling turned and the bigger the angular velocity was resulted. In other words, when you take a long road cycling with your saddle fixed at a little lower height than the average one, you will consume less physical strength and expect better performance.

      • SCIESCOPUSKCI등재

        Changes of Sugar Composition and Related Enzyme Activities during Fruit Development of Asian Pear Cultivars ‘Niitaka’ and ‘Whangkeumbae’

        Jin-Ho Choi,Jang-Jeon Choi,Chang-Seok Bang,Jung-Sup Lee,Dong-Woog Choi,Hye-Sun Cho,Jun Cheul Ahn 한국원예학회 2009 Horticulture, Environment, and Biotechnology Vol.50 No.6

        We report on the seasonal changes of soluble sugar accumulation and several enzyme activities related to sugar metabolism, in two Asian pear cultivars (Pyrus pyrifolia) cultivars ‘Niitaka’ and ‘Whangkeumbae’. Soluble sugar content increased as the fruit developed and its total contents in matured fruits were 104.6 and 95.1 ㎎ㆍg?¹ fresh weight for ‘Niitaka’ and ‘Whangkeumbae’, respectively. However, the fructose-glucose-sucrose-sorbitol ratio was not significantly changed. Sorbitol-6-phosphate dehydrogenase activity was maintained at high level in leaves and low in fruits throughout the fruit development, although the enzyme activity highly fluctuated in young and mature fruits. NAD-dependent sorbitol dehydrogenase activity increased sigmoidally in both leaves and fruits during fruit development, and correlated with accumulation of total sugar in fruits. Sucrose synthase and sucrose phosphate synthase (SPS) activities remained low in leaves, but higher with two peak fluctuations in fruits. The change of soluble sugar contents positively correlated with SPS activity, based on the seasonal fluctuation of SPS activity and soluble sugar accumulation.

      • KCI등재후보
      • Rat의 복강내에 투여한 5-fluorouracil-polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

        강대영,송규상,최정목,노승무,정경수,오정연,김진향,양준묵,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

        For more effective intraperitoneal chemotherapy, the authers made 5-fluorouracil-polyglycolic acid composite disks(FU-PGA disks) with 5-fluorouracil and polyglycolic acid, a biodegradable polymer. We inserted the FU-PGA disk into the peritoneal cavites of Sprague-Dawley male rats, the control and three experimental groups; one FU-PGA disk insert group(300mg/kg), two FU-PGA disk insert group(600mg/kg), and three FU-PGA disk insert group(900mg/kg). The control group received a similar number of PGA disk inserts. A pharmacokinetic study was performed to measure the 5-fluorouracil concentration in the peritoneal fluid, blood, and tissues(liver, kidney and heart) at 24 hours, 72hours and 168 hours after insertion of the FU-PGA disk. Light and electron microscopic studies were done. The results were as follows: 1) The number of white blood cells and platelets decreased after FU-PGA insertion. The degree was proportional to the duration and amounts inserted. The change in the number of red blood cells varied slightly. 2) Light microscopically, slight changes were noted at 168 hours in the 3 disk insert group (900mg/kg). Mild fatty change and hepatocyte degeneration around the central veins of the liver were noted, with vacuolar degeneration in the proximal convoluted tubules of the kidney. 3) Electron microscopically,the liver showed focal increases of lipid droplets in the hepatocytes, and irregular nuclear membrane with focal nucleolar segregation of the fibrillar and granular elements. Also the double membranous structure of the hepatocytes and Kupffer cells was widened with bleb formation. The kidney showed wide separation of the nuclear double membrane in the proximal convoluted tubular cells and mesangial cells, with vacuolation and myelin figure formation in the mitochondria of the proximal convoluted tubular cells, at 72 hours and 168 hours in the 2 to 3 FU-PGA insert groups. The heart showed focal loss of cristae,vacuolation and myelin figure formation in the mitochondria of the 2 to 3 FU-PGA insert groups. In conclusion, despite the large amont of FU-PGA inserted, the histopathological changes in the liver, kidney and heart were slight, and consonant with the very low amount of 5-fluorouracil concentrations detected in the liver, kidney and heart. The above results suggest that the FU-PGA composite can serve as a new device for releasing drugs in a controlled manner and easily targeted to intraperitoneal organs. This device can improve the efficacy of intraperitoneal chemotherapy for gastric cancer.

      • SCOPUSKCI등재

        급성 췌장염으로 발현된 낭성 변화를 이릉킨 종격동 부갑상선 선종 1예

        이준호,최영식,박진홍,허갑도,윤설영,최소진,권태헌,이창렬,손성표,박영효 대한내분비학회 1998 Endocrinology and metabolism Vol.13 No.3

        Hypercalcemia due to hyperparathyroidism is rarely associated with acute pancreatitis. But, the relationship between hypercalcemia and pancreatitis still remains controvesial. Ectopic parathyroid adenoma with cystic change is one of the rare causes of hyperparathyroidism, and is usually located in neck and mediastinum. We report a case of mediastinal parathyroid adenoma with cystic change associated with acute pancreatitis. A 54-year-old male presented with epigastric pain for 3 days. The serum calcium, phosphate, elastase were 16.8mg/dL, 1.1 mg/dL, 2772.0 ng/mL respectively and his parathyroid hormone level in serum was 651.84 pg/mL. Chest CT showed a mediastinal mass with well defined inhomogenously enhanced density located between SVC and aorta. The patient was diagnosed to hyperparathyroidism with acute pancreatitis due to mediastinal parathyroid adenoma with cystic change, and was surgically removed. The surgical biopsy showed parathyroid adenoma with cystic change. After operation his general condition was improved and serum calcium, phosphate, amylase, lipase level were normalized (J Kor Soc Endocrinol 13:473-479, 1998).

      • SCOPUSSCIEKCI등재

        척수손상후 운동 유발전위와 지각 유발전위의 비교

        지철,이재수,하영수,최창락,송진언 대한신경외과학회 1987 Journal of Korean neurosurgical society Vol.16 No.4

        Electrical monitoring of the nervous system offers the potential for the detection of injury, intraoperatively. The relationship of MEP(Motor Evoked Potential) and SEP(Sensory Evoked Potential) taken in 30 rats before and after spinal cord injury is reported. MEP was obtained from distal portion to the site of spinal cord injury by electrical stimulation of the cerebral motor cortex after insertion of a ball electrode in the cerebral motor cortex. SEP was collected at the cerebral somatosensory cortex during the sciatic nerve stimulation. Experimental animals were divided into a 20g㎝ spinal cord-trauma group and 50g㎝ spinal cord-trauma group. Changes of cardiopulmonary function after cerebral motor cortex stimulation and pre-and post-injury MEP and SEP were obtained at constant time interval. The results were follows : 1) Significant changes in blood pressure, pulse rate, and respiratory rate were noted to be elevated after stimulation of cerebral motor cortex and these were returned to normal in 10 minutes after stimulation. 2) MEP in control group showed that the latency was 8.6±1.54msec and the amplitude was 20.60±3.2㎶. In MEP of 20g㎝ spinal cord trauma group, the latency was increased to 30% (11.26±1.76msec) compared to control group at 10 minutes after the injury and the amplitude was decreased to 29% (14.60±2.99㎶). The latency was slowly decreased with the passage of time, to 21% increase. (10.42±1.84msec) at 1 hour after injury but the amplitude was not changed. In 50 g㎝ spinal cord-trauma group the latency was decreased to 75%(4.9±1.52㎶) compared to control group. With the passage of time, no change was revealed in latency but amplitude was decreased. The amplitude was decreased to 80%(4.00±1.49㎶) compared to control group. Change of MEP was marked in 50g㎝ spinal cord-trauma group. With the passage of time MEP was slightly improved in 20g㎝ spinal cord-trauma group but deteriorated in 50g㎝ spinal cord-trauma group. 3) The latency of SEP in control group was 12.22±0.7msec and the amplitude of those was 20.00±2.21㎶. No significant statistical change was recorded in the SEP of each spinal cord-trauma group compared to control group. MEP might be more important indicator than SEP in estimation and evaluation of the functional change of spinal cord injury.

      • KCI등재

        Sphingosine 1-Phosphate and Sphingosine Kinase Activity during Chicken Embryonic Development

        Chang-Hwan Choi,정지선,Bo-im Yoo,You-Xun Jin,문동철,유환수,오세관,홍선표,이용문 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.4

        The chicken embryo has been well used in studies of the developmental process, and during development sphingosine and sphingosine 1-phosphate (So1P) are considered critical mediators of cell death and survival. In this study, we compared the sphingolipid contents of chicken embryos during the early embryonic development period from day 3 to day 6. HPLC analyses of sphingosine and So1P in chicken embryos revealed that sphingosine levels were greatly reduced on day 4 whereas So1P levels were not significantly changed. Sphingosine kinase (Sphk) activities, which require sphingosine as substrate to produce So1P, were also greatly reduced on day 4. Collectively, we found sphingosine levels and Sphk activities, but not So1P levels are changed in early stage of chicken embryos development.

      • Investigation of high contrast and reversible luminescence thermochromism of the quantum confined Cs<sub>4</sub>PbBr<sub>6</sub> perovskite solid

        Choi, Jin Woo,Cho, Namchul,Woo, Hee Chul,Oh, Byeong M.,Almutlaq, Jawaher,Bakr, Osman M.,Kim, Sung-Hoon,Lee, Chang-Lyoul,Kim, Jong H. The Royal Society of Chemistry 2019 Nanoscale Vol.11 No.12

        <P>Thermochromism of organic/inorganic halide perovskites has attracted particular interest due to their potential applications as photoluminescence (PL)-based temperature sensors. However, despite the outstanding PL characteristics, their use as a thermochromic material in practical temperature ranges has been limited because of their poor thermal stability. In this study, we used the quantum confinement effect and exceptional PL quantum efficiency of the Cs4PbBr6 perovskite to demonstrate their high on/off ratio (20) and reversible PL thermochromism in the solid state in practical temperature ranges including room temperature (RT). Systematic photophysical and optical characterization studies, including exciton-phonon scattering, exciton binding energy, exciton decay dynamics, and crystal structure change, were performed to investigate the origin of this unique thermochromic PL property. The results showed that the efficient and highly reversible thermochromic PL emission of the Cs4PbBr6 perovskite is due to its desirable optical properties such as highly luminescent emission, efficient PL quenching at high temperatures, and thermally reversible structural changes.</P>

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