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      • 운동 직후 고온 침수가 EPOC와 TG/ fatty acid cycling에 미치는 영향

        조현철,김종규,강민철,홍완표,박노혁 龍仁大學校 體育科學硏究所 2005 體育科學硏究論叢 Vol.15 No.1

        The purpose this study was to estimate effects of EPOC and TG/fatty acid cycling on warm water immersion of immediately after exercise. To elucidate the role of fatty metabolism, a sequence of five experiments was performed. Seven physically active, male subjects volunteered to participate in the presented study. The mean values for age, body mass and hight were 25±1.52 yr, 79.2±9.52kg, 177.2±4.62cm, respectively. After giving consent, participant visited the laboratory on six occasion: 1) 30min of treadmill exercise VO2max 55% and a further 60min recovery, 2) 30min partial body warm water immersion in a 39℃ and a further 60min recovery, 3) 30min whole body warm water immersion in a 39℃ and a further 60min recovery, 4) 30min of treadmill exercise VO2mas 55% and in 30min partial body warm water immersion in a 39℃, 5) 30min of treadmill exercise VO2max 55% and in 30min whole body warm water immersion in a 39℃. When compared by recover period within repeat on the base of changes of subjects average body temperature, not effective interactions among repeat. However, partial and whole body warm water immersion immediately after exercise shows it as the best effective exercise for VO2max 55%, partial and whole body warm water immersion. When compared by recover period within repeat on the base of changes of subjects EPOC, effective interactions among repeat(p<.05). Partial and whole body warm water immersion immediately after exercise shows it as the best effective exercise for VO2mas 55%, partial and whole body warm water immersion. The catecholamines concentration was significantly higher partial and whole body warm water immersion than exercise of VO2max 55%(p<.05). The TG concentration and free fatty acid was significantly higher partial and whole body warm water immersion immediately after exercise than exercise of VO2max 55% than Partial and whole body warm water immersion(p<.05). Based on the facts that we have discussed above, human metabolism is increased by both exercise and conditions of immersion and partial and whole body warm water immersion immediately after exercise than exercise of VO2maw 55% shows it as better effective treatment for increasing TG/Fatty acid cycling activation. Due to extremely heavy stress complained by subjects during whole body immersion, it is thought that more researches on it should be required.

      • 쿠싱증후군 환자에서 당 대사 이상 정도에 따른 인슐린 감수성과 인슐린 저항성의 변화

        정인경,김성훈,정재훈,민용기,이명식,이문규,유형준,안규정,노정현,김동준,김광원 대한내분비학회 2003 Endocrinology and metabolism Vol.18 No.4

        연구배경 당질 코르티코이드는 당 대사에 매우 중요한 호르몬으로 내인성 당질 코르티코이드 과다상태인 쿠싱증후군에서는 말초조직에서 인슐린 저항이 증가하고 이를 보상하고자 인슐린 분비의 증가로 고인슐린혈증이 동반된다고 보고되고 있다. 하지만 생체 내에서와 달리 시험관내에서는 췌도세포에 당질 코르티코이드를 장시간 처리하면, 인슐린 분비 및 생합성이직접적으로 억제됨이 확인된 바 있어 쿠싱증후군 환자에서 당뇨병의 원인으로는 아마도 말초조직에서 증가된 인슐린 저항성 뿐 아니라 이를 충분히 보상하지 못하는 췌장에서의 인슐린 분비 저하가 같이 동반되어있지 않을까 하는 가설을 세우게 되었고, 아직까지 당질코르티코이드가 당대사 이상을 일으키는 기전에 대해 쿠싱증후군을 당대사 정도에 따라 인슐린 감수성과 분비능을 분석한 연구는 없었기에 이를 알아보고자 하였다. 방법: 삼성서울병원에서 쿠싱증후군으로 진단 받은 환자 15명을 대상으로 하였다. 이에 대한 대조군으로는 쿠싱증후군 환자와 같은 성별 그리고 체질량지수를 갖은 15명의 건강한 성인을 대상으로 비교 하였다 쿠싱증후군 환자를 대상으로 경구당부하 검사를 통해 당대사 정도를 정상군, 내당능장애군, 그리고 당뇨병군으로 나눈 후 정맥 당부하 검사를 시행하여 각군의 인슐린 저항성과 인슐린 분비능의 지표를 비교하고, 수술 후 쿠싱증후군이 완치된 상태에서 수술 전후의 당대사 지표의 변화를 조사하였다. 결과: 1) 쿠싱증후군 환자 중 정상인은 20%, 내당능 장애는 27%, 그리고 당뇨병은 53%였다. 체질량지수, 나이, 그리고 발병 기간은 세 군간에 의미 있는 차이가 없었으나, 24시간 소변검사의 코르티솔 농도는 당뇨병군에서 의미있게 높았다. 2) 정맥당부하 검사 결과, 인슐린 감수성 지표인 Sl는쿠싱증추린」서 1.58±0.10[×10^(-4)(min^(-1)(μU/mL)^(-1)]로 정상 대조군의 3.37±0.49[×10^(-4)(min^(-1)(μU/mL)^(-1)]에 비해 의미있게 낮았으나(P=0.024), 쿠싱증후군 환자 중 NGT, IGT, DM 군간에 서로 통계적인 차이는 없었다. 3) SG는 정상 대조군과 쿠싱증후군 환자간에는 의미있는 차이가 없었고, 쿠싱 증후군에 있어서 당대사가 악화될수록 감소하는 경향을 보였으나 의미있는 차이는 없었다. 4) 인슐린 분비능의 지표인 AIRg는 정상인에 비해 전체 쿠싱증후군 환자의 경우 증가하는 경향을 보였으나 의미있는 차이는 없었다. 하지만 쿠싱증후군 환자중에서 당대사 상태에 따라 NGT군은 1299 (1297∼1310)(mu/g/min ×10^(-2))로 정상 대조군(368.9±98.6[mu/g/min ×10^(-2)]) 보다도 의미있게 높았고, DM군{202.2 (91.1~371.4) [mu/g/min ×10^(-2)}은 NGT군에 비해 의미있게 낮았다(P=0.0031). 5) 15명중 현재 완치 상태에 있는 6명에 대해 수술전과 후로 비교하였다. 수술 전 당대사 상태가 1명은정상, 1명은 내당능 장애, 그리고 4명은 당뇨병이었으나 수술 후 시행한 경구 당부하 검사상 모두 정상 당대사 상태를 보였다. 6) 수술 후 완치된 환자 6명에 있어 인슐린 감수성지표인 Sl는 수술전에 중앙값이 1.22[×10^(-4)(min^(-1)(μU/mL)^(-1)]로 대조군에 비해 의미있게 감고』어 있었으나(p.0.05), 수술후 10.95 [×10^(-4)(min^(-1)(μU/mL)^(-1)]로 정상 수준으로 회복되었고(P=0.0022), 인슐린 분비능을 나타내는 AIRg [mu/g/min ×10^(-2)] 값도 정상수준으로 회복되었다. 특히 인슐린 분비능의 회복양상은 혈당농도에 따라 판이하게 나타나서, 정상과 내당능장애 상태에 있던 2명은 수술전에 1201 [mu/g/min ×10^(-2)]로 증가되어 있던 AIRg 값이 수술 후 정상 수준으로 감소하였고, 수술 전에 당뇨병 상태에 있던 4명의 경우 245.9 [mu/g/min ×10^(-2)]로 인슐린 분비능이 감고il어 있었는데 이들은 수술 후 모두 정상 수준으로 증가되었다 (P=0.0286). 결론: 쿠싱증후군 환자에서 당대사 이상은 80%로 높은 유병률을 보였다. 모든 쿠싱증후군환자에서 인슐린 감수성은 정상인에 비해 저하되어 있어 말초조직의 인슐린 저항이 선행됨을 시사하며, 인슐린 분비능은 당대사의 정도에 따라 다르게 나타났는데, 정상 당대사군에서는 인슐린의 저항성을 극복할 만큼 정상 대조군보다 더 많은 양의 인슐린 분비를 하다가 고코르티솔혈증이 심할수록 인슐린 분비능의 감소로 당뇨병으로 진행됨을 확인할 수 있었고, 이런 인슐린 저항성과 인슐린 분비장애는 수술 후 다시 회복되는 가역적인변화를 보였다. Background: Glucocorticoid plays an important role in the control of carbohydrate metabolism. Patients with Cushing's syndrome have been reported to have an increased incidence of carbohydrate intolerance due to peripheral insulin resistance and hyperinsulinemia, although the exact incidence and nature of this disorder have remained unclear. Few results have been published about insulin resistance and insulin secretion according to the level of glucose concentration, or about the reversibility of such defects in patients with Cushing's syndrome. Methods: To assess the effect of glucocorticoid on the insulin sensitivity and insulin secretion in Cushing's syndrome, 15 patients with Cushing's syndrome were classified into 3 groups (normal glucose tolerance: NGT, impaired glucose tolerance: IGT, diabetes: DM) according to the degree of glucose tolerance based on the oral glucose tolerance test (OGTT). Insulin modified, frequently sampled, intravenous glucose tolerance test (FSIGT) was performed before and after curative surgery on these patients and on 15 healthy control subjects. Data were evaluated by non-parametric statistical analysis. Results: 1) Among the 15 patients with Cushing's syndrome, 3 (20%) were NGT, 4 (27%) IGT, and 8 (53%) DM, based on OGTT. Twenty-four hour urinary free cortisol (UFC) was significantly higher in the DM group. 2) Insulin sensitivity index (SI) of Cushing's syndrome was significantly lower than that of the control group p=0.0024), but was not significantly different among the three Cushing's syndrome groups of NGT, IGT and DM. 3) Glucose mediated glucose disposal (SG) (Ed- confirm this abbreviation; it does not seem to match the definition) of Cushing's syndrome was not significantly different from that of the control group. 4) Insulin secretion (AIRg) of Cushing's syndrome tended to be high, but it was not significantly different from that of control. However, according to the level of glucose concentration there was significant difference in AlRg among the three Cushing's syndrome groups p=0.0031); AIRg of DM was significantly lower than that of NGT. 5) After surgical treatment, parameters of insulin sensitivity and insulin secretion were normalized in 6 cured patients; 1 with NGT, 1 with IGT, and 4 with DM, preoperatively. Median SI of all 6 patients was significantly improved up to the normal range postoperatively p=0.0022). Median AIRg of these 6 patients was balanced around that of normal control postoperatively p=0.0286). Conclusion: Eighty percent of patients with Cushing's syndrome had abnormality of carbohydrate metabolism. Insulin sensitivity was significantly decreased in Cushing's syndrome. Insulin secretion was significantly higher only in the NGT and IGT groups of Cushing's syndrome. As the hypercortisolemia is exacerbated, insulin secretion is significantly decreased and causes DM, suggesting that glucocorticoid has a direct or indirect toxic effect on the pancreatic beta cell (J Kor SOC Endocrinol 18:392-403, 2003).

      • KCI등재

        모과내 기능성 유용성분 용매추출공정의 최적화

        전주영 ( Ju Yeong Jeon ),조인희 ( In Hee Jo ),경현규 ( Hyun Kyu Kyung ),김현아 ( Hyun A Kim ),이창민 ( Chang Min Lee ),최용희 ( Yong Hee Choi ) 한국산업식품공학회 2010 산업 식품공학 Vol.14 No.2

        본 연구에서는 모과내의 여러 가지 기능성 유용성분을 효과적으로 추출하기 위해서, 모과나무의 익은 열매로 만든 약재인 모과를 사용 하였다. 모과의 기능성 유용성분용매 추출 공정의 최적 조건을 확립하고자 하였다. 모과를 에탄올에 추출하여 반응표면 분석법으로 모니터링하여 최적 용매 조건을 설정하였다. 중심합성계획법에 따라 시료에 대한 용매비(X1)와 추출온도(X2), 추출시간(X3)을 요인변수로 하고 추출수율(Y1), 총페놀 함량(Y2), 전자공여능(Y3), 갈색도(Y4), 환원당(Y5)을 종속변수로 하여 시행하였다. 실험 결과 추출수율은 추출 온도와 추출 시간에 유의하게 영향을 받음을 알 수 있었다. 안장점에서 추출조건은 시료에 대한 용매비는 26.38mL/g, 추출온도는 72.82oC, 추출시간은 74.86 min에서 최대값을 나타내었다. 총페놀 함량은 용매비와 시간에 영향을 거의 받지 않았고 추출시간에는 영향을 받았으며, 최대값은 20.70mg/mL 로 나타났다. 이때의 추출조건은 시료에 대한 용매비는 22.61mL/g, 추출온도는 84.49oC, 추출시간은 77.25 min으로 나타났다. 전자공여능은 추출온도에 따라 유의하게 영향을 받은 것으로 나타났다. 안장점에서의 추출조건인 시료에 대한 용매비 10.65mL/g, 추출온도 67.78oC, 추출시간 96.75 min에서 추출수율은 94.12%로 예측되었다. 갈색도에 대한 추출조건은 시료에 대한 용매비 23.77mL/g, 추출온도 87.27oC, 추출시간 96.68 min 일 때 안장점이 나타났다. 환원당은 시료에 대한 용매비 26.83mL/g, 추출온도 82.167oC, 추출시간 81.94 min에서 10.55mg/mL로 최대값을 나타내었고 추출시간에 영향을 받았다. In this study, various active functional components in Chinese Quince were extracted by solvent extraction method. A central composit design for optimization was applied to investigate the effects of independent variables such as solvent to sample ratio (X1), extraction temperature (X2), and extraction time (X3) on the soluble solid contents (Y1), total phenols (Y2), electron donating ability (Y3), browning color (Y4) and reducing sugar contents (Y5). It was found that extraction temperature and extraction time were the main effective factors in this extraction process. The maximum soluble solid contents of 35.77% was obtained at 26.38mL/g (X1), 72.82oC (X2) and 74.86 min (X3) in saddle point. Total phenols were rarely affected by solvent ratio and extraction time, but it was affected by extraction temperature. The maximum total phenols of 20.70% was obtained at 22.61mL/g (X1), 84.49oC (X2), 77.25 min (X3) in saddle point. The electron donating ability was affected by extraction time. The maximum electron donating ability of 94.12% was obtained at 10.65mL/g (X1), 67.78oC (X2), 96.75 min (X3) in saddle point. The maximum browning color of 0.32% was obtained at 23.77mL/g (X1), 87.27oC (X2), 96.68 min (X3) in saddle point. The maximum value of reducing sugar content of 10.55% was obtained at 26.83mL/g (X1), 82.167oC (X2), 81.94 min (X3). Reducing sugar content was affected by extraction time.

      • Development of Simultaneous Analytical Method for ImidazolinoneHerbicides from Livestock using LC-MSMS

        Hyo-Min Heo,Hyeong-WookJo,Kyu-Won Hwang,Jung-Hun Sun,Joon-Kwan Moon 한국농약과학회 2021 한국농약과학회 학술발표대회 논문집 Vol.2021 No.11

        Simultaneous analytical method using LC/MSMS for imidazolinone herbicides from livestock (egg, milk, beef, pork and chicken) for monitoring was developed with QuEChERS preparation. Sample weighing (5g) in a 50mL conical tube, added 0.1 M potassium phosphate dibasic solution (5mL) was shaken for 10min. After 0.5mL 6 NHCl, 10mL acetonitrile were added, it was shaken for 10min. And QuEChERS extraction salt (Original method, 4g MgSO₄, 1g NaCl) were added to the sample in the 50 mL conical tube. The mixture was strongly shaken for 1 min and was centrifuged at 3,000g for 10 min. The acetonitrile layer was purification with dSPE (150mg MgSO₄, 25mg C18) and was centrifuged at 13,000g for 5min. The supernatant was filtered with a membrane filters (pore size: 0.2um) before analysis. ME (%, Matrix effect) for almost analytes range were -6.56 to 5.70%. MLOD (Method LOD) and MLOQ (Method LOQ) was calculated by S/N ratio. MLOQs were 0.01 mg/kg. The linear correlation coefficients (r2) were > 0.99 within the range of 2 ~ 100 ug/kg for all of the 3 imidazolinone herbicides. The percentages (of imidazolinone herbicides) recovers were in the range of 84.1 ~ 110.6% (0.01mg/kg level), 90.8 ~ 97.1% (0.1mg/kg level) and 94.4 ~ 102.1% (0.5mg/kg level) within the validation criteria (recover; 70-120% with RSD < 20%)

      • SCIESCOPUSKCI등재
      • KCI등재후보

        실험적 급성 허혈성 신부전에서 Verapamil 이 혈중 Polyamine 동태에 미치는 영향

        원동준(Dong Jun Won),권현민(Hyun Min Kwon),김용섭(Yong Seop Kim),구자룡(Ja Ryong Gu),권영주(Young Ju Kwon),조원용(Won Yong Cho),김형규(Hyung Kyu Kim) 대한내과학회 1991 대한내과학회지 Vol.40 No.6

        N/A It has been proposd that calcium entry from an external medium increases intracellular free calcium to toxic levels during ischemic acute renal failure, and verapamil (ARF) has been suggested as the agentblocking calicium entry into renal cells and protecting renal function during ischemic injury. Polyamines, anorganic cations that play various roles in normal cellular proliferation and differentiation, accumulate in renal failare. Alsa it has been suggested tht the synthesis and metabolism of polyamine are influence by acute changes of the general condition, such as acute renal failure, and are mediated by a calcium influx into the cells. The study was designed to study the protective effects of systemic verapamil pretreatment on renal function and the influence on polyamine metabolism in experimental ischemic ARF in cats. For these purpose, the experimental animals were divided into 2 groups. While Group I (n=5) was an ischemic ARF model by renal artery clamping for 60 minutes, Group II (n=5) was ischemic ARF with systemic verapamil (5 ml/min/kg) pretreatment. The creatinine clearance and plasma and urinary polyamine were measured in each group before and after the renal artery clamp. The results were as follows: 1) Creatinine clearance before and after the renal artery clamp were 10.64±7.18 ml/min/kg and 2.09±1. 70 ml/min/kg in Group I, 4.47±3.38 ml min/kg and 0.60±0.79ml/min/kg in Group II, respectively, So creatinine clearance decreased more significantly in Group II campared with Group I. 2) Plasma polyamine increased after ischemia in Group I. In group I, plasma levels of putrescine, spermidine, and spermine before ischemia were 4.75±0.40 nmol/ml, 0.69±0.09 nmol/ml, and 0.83±0.63 nmol/ml, were elevated to 7.17±2.91 nmol/ml, 9.83±1.46 nmol/ ml, and 2.64±1.14nmol/ml after ischemia. But in Group II, the plasma level of polyamine was not changed, and especially, spermine decreased significantly from 0.83±0.27 before ischemia to 0.49±0.23 nmol/ml after ischenmine (p=0.033). 3) Urine polyamine excretion decreased after ischemia in Group I and Group II. In Group II, urinary excretion of spermidine and spermine before ischemia, 0.13±0.10 nmol/min and 0.17±0.13nmol/min, decreased after ischemia to 0.01±0.01nmol/min (p=0.019) and 0.032±0.26 nmol/min (p=0.0257). 4) In renal tissue, spermine content vas highest. In Group II, preischemic spermine were 397.20 nmol/g and increased to 646.66nmol/g after ischema, But there were no significant changes in the polyamine contents in Group II. From these data, it was suggested that systemic verapamil pretreatment exerts no protective effect on ischemic ARF. Plasma polyamines are elevated in ischemic ARF, and verapamil may protect these elevations.

      • KCI등재

        Process Design and Fabrication of Sample for Non‑contact Liquid Crystal Alignment with High Yield

        Minkyu Seo,Jeong‑min Han,Jin‑geun Shon 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.1

        In this study, we report the results of an experiment for aligning liquid crystals (LCs) by irradiating ultraviolet rays that are not polarized to an alignment layer, and a simulation result on the alignment principle. In the case of irradiating un-polarized ultraviolet rays to the substrate coated with the alignment flm, there have been many experimental reports on the alignment mechanism of the LC due to the anisotropy generated in the substrate, but the theoretical approach is somewhat lacking. As a result of the experiment, the best orientation was observed at around 45°. As a result of the simulation, it was found that the maximum diference between the p-polarization and the s-polarization was within the range of similar angles there was. The theoretical approach to the alignment mechanism of LC was possible. And we have experimentally confrmed that the mechanism of liquid crystal alignment by conventional Groove theory is possible by irradiation of unpolarized UV light. The AFM analysis confrmed that the surface anisotropy that causes this orientation principle actually occurs in the unpolarized UV light. It is expected that this non-contact orientation method can realize higher production yield than the conventional contact type rubbing method, and the result of this study could contribute to the improvement of the yield.

      • 해도 정보를 이용한 선박의 최적 항로 생성

        김민규(Min-Kyu Kim),김종화(Jong-Hwa Kim),양현(Hyun Yang) 한국항해항만학회 2022 한국항해항만학회 학술대회논문집 Vol.2022 No.2

        Min-Kyu Kim*․Jong-Hwa Kim**․†최근 자율 운항 선박에 대한 관심이 높아지고 있다. 특히, MUNIN (Maritime Unmanned Navigation through Intelligence in Networks) 프로젝트를 계기로 자율 운항 선박에 대한 개발과 연구가 활발히 진행되고 있다. 또한 국제해사기구 IMO는 자율 운항 선박 시대에대응하기 위해 자율 선박을 MASS (Maritime Autonomous Surface Ship)라 정의하고 선박 자율화 정도에 따라 4단계 등급을 제시하고 있다. 완전한 자율 운항 선박에 대한 요구조건을 만족하기 위해서는 항로 결정과 제어기술이 필수적이다. 본 연구에서는 여러 가지 기술 중 선박의최적경로를 생성하는 기법을 다룬다. 기존에 최적항로를 생성하기 위한 방법으로는   , Dijkstra와 같은 알고리즘들이 주로 사용되었다. 그러나 이와 같은 알고리즘은 섬이나 육지에 대한 충돌 회피는 고려하고 있지만 수심 및 연안 선박에 대한 규정들은 고려하지 않고 있어실제로 적용하기에는 한계점이 있다. 따라서 본 연구에서는 안전을 위해 선박의 선저 여유 수심과, 해도에 규정되어 있는 선박 운항에 대한여러 규정들을 반영하여 최적 항로를 생성하고자 한다. 최적 항로를 생성하기 위한 알고리즘으로는 강화학습 기반의 Q-learning 알고리즘을적용하였다.

      • Enhanced Extraction of trans-Resveratrol from Polygonum cuspidatum by a Combination of Thermal and Enzymatic Treatment

        Kyu Hyun Kim,Min Ju Kim,Yu Jin Lee,Eun Jeong Kwon,Chan Ho Jang,Jong-Sang Kim 한국식품영양과학회 2021 한국식품영양과학회 학술대회발표집 Vol.2021 No.10

        Resveratrol (RES), a naturally occurring phytoalexin, has been known for health beneficial functions, such as cardioprotective, antihypertensive, and antiaging properties. The root of Polygonum cuspidatum Sieb. et Zucc. (P. cuspidatum) is extensively used as a good source of trans-RES, the most bioavailable form of RES. Our previous study showed an improved conversion rate of piceid (PD) present in grape peel into RES by pre-heating at 95°C for 10 min, followed enzymatic hydrolysis at 50°C for 60 min. In this study, we examined if combined thermal and enzymatic treatment could maximize extractability of PD and RES from P. cuspidatum. Results from this study showed that the treatment of P. cuspidatum with Viscozyme dramatically increased the conversion of PD into RES as well as the entire extractability of RES and PD among several enzymes tested. Furthermore, 60% and 80% ethanolic solvents showed the best extraction yield of RES. The extraction method established in this study is a low-cost green processing strategy and could be applied to maximize extraction of bioactive trans-RES from P. cuspidatum.

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