Model Simulation of a HF Chemical Laser and Numerical Analyses of It's Behaviors

김양미,김웅,조웅인,Yang Mee Kim,Ung Kim,Ung-In Cho Korean Chemical Society 1989 대한화학회지 Vol.33 No.2

화학 레이저 모델의 이론적 연구를 화학 반응속도론, gain 과정과 유도 방출과정을 고려하여 수행하였다. 우선 F+$H_2$비 연쇄반응 HF 화학 레이저를 진동준위가 v = 3 까지 pumping되는 것으로 생각하고 관련된 rate equation을 풀어서 출력을 산출하였다. 여기서 조화진동자를 가정한 계산과 비조화성 보정을 해준 계산결과의 비교로부터 그 차이가 거의 없음을 확인하였다. 또한 여러가지 온도와 초기농도를 택하여 산출되는 laser 축력의 변화를 검토하였다. 그리고 $H_2$+$F_2$ 연쇄반응 HF 화학 레이저에 관한 비교적 단순한 model simulation을 수행하였다. 이 계산 결과는 이미 보고된 상당히 복잡한 계산결과와 비교하여 만족할 정도이었다. Theoretical analysis of HF chemical laser models are performed through chemical reaction kinetics, gain process and stimulated emission process. A chemical laser of F+$H_2$ nonchain reaction is investigated through V-R transitions of excited HF for vibrational levels up to v = 3 and rate equations including nonchain pumping and deactivation. On this analysis, harmonic and anharmonic vibrational levels are considered separately and the results of the corresponding power calculations are showed very small difference between the two. Output powers are calculated with variation of temperature and initial concentrations of $H_2$. A HF chemical laser of $H_2$+$F_2$ chain reaction is also simulated with a premixed initial condition. Results of present model calculations are satisfactory through comparison with detailed calculations reported by others.

미국 사회복지정책의 경과와 특징

김양미 ( Yang Mi Kim ) 한국민족연구원 2012 민족연구 Vol.0 No.51

The purposeof the study was to analyze structural background of American social welfare policy to examine features of American social welfare policy, to examine that the structural background was disclosed in the development process of American social welfare in anyway through concrete cases and to examine features and implication of American social welfare. America kept passive attitude for development to a welfare country, differing from European countries, while advanced countries including Europe had realized a welfare country by developing a welfare system during the period of earlier centuries. The results of the study were as follows. In features of American social welfare policy, public social welfare development led by federal government was low, but the discretionary power of state government or local government was strong. And there are distinct differences in American people`s preference between programs operated by contribution and by non-contribution by separating social welfare system to double structure. In the problem of poverty, a racial prejudice has a negative effect on developing American social welfare. It causes the above features that individualistic liberalism which was American values had a continuous effect on formation and development of social welfare policy.

TREK2-채널 과발현 세포주에서 에피갈로카테킨-3-갈레이트의 세포 증식 억제 효과

김양미(Kim, Yang-Mi),김경아(Kim, Kyung-Ah) 한국산학기술학회 2016 한국산학기술학회논문지 Vol.17 No.3

Two-pore 도메인 포타슘 채널(two-pore domain K+ channel, K2P channel)은 세포내 pH, 생리 활성 지질, 신경 전달 물질과 같은 생리학적 자극의 표적이며 안정막전압(resting membrane potential)을 설정하는 것으로 알려져 있다. 일부 유형의 K2P 채널들은 세포 사멸 및 종양 형성 등에서 중요한 역할을 한다. K2P 채널 중 TREK2 채널의 길항제는 보고되지 않았다.본 연구의 목적은 TREK2 채널을 과발현시킨 HEK293 세포(HEKT2)에서 플라보노이드에 의해 TREK2 채널이 억제되는지 그리고 HEKT2 세포의 증식이 플라보노이드에 의해 영향을 받는지 알아보고자 하였다. 전기생리학적 전류는 단일 채널 patch clamp 방법을 사용하여 기록하였고 세포 증식은 XTT 에세이방법을 이용하여 측정하였다. HEKT2 세포에서 전기생리학적 TREK2 채널 활성도는 에피갈로카테킨-3-갈레이트(EGCG) 및 케르세틴과 같은 플라보노이드에 의해 각각 91.5±13.1%(n=5), 82.2±13.7%(n=5)까지 억제되었다. 반면, EGCG 유사체인 에피카테킨(EC)는 TREK2 단일 채널 활성도에 현저한 억제 효과는 없었다. 또한 HEKT2 세포에서 세포 증식이 EGCG에 의해 69.4±14.0%(n=4)까지 감소되었음을 확인하였다. 결과로부터 EGCG와 케르세틴이 TREK2 채널 억제제임을 처음으로 확인하였고, EGCG만 HEKT2 세포의 증식을 감소시킨다는 결론을 얻었다. 본 연구의 결과는 EGCG 및 케르세틴이 TREK2 채널을 억제함으로써 막전압의 변화 유도와 세포 증식에 필요한 세포내 신호 변화의 시작을 트리거하는데 일차적으로 작동할 수 있음을 시사한다. Two-pore domain potassium (K2P) channels are the targets of physiological stimuli, such as intracellular pH, bioactive lipids, and neurotransmitters, and they set the resting membrane potential. Some types of K2P channels play a critical role in both apoptosis and tumoriogenesis. Among the K2P channels, no antagonists of the TREK2 channel have been reported. The aim of the present study was to determine if the TREK2 channel is blocked and whether cell proliferation is influenced by flavonoids in the TREK2 overexpressing HEK293 cells (HEKT2). The electrophysiological current was recorded using single channel patch clamp techniques and cell proliferation was measured using a XTT assay. The electrophysiological results showed that the TREK2 channel activity was reduced to 91.5±13.1% (n=5) and 82.2±13.7% (n=5) by flavonoids, such as epigallocatechin-3-gallate (EGCG) and quercetin in HEKT2 cells, respectively. In contrast, the EGCG analogue, epicatechin (EC), had no significant inhibitory effects on the TREK2 single channel activity. In addition, cell proliferation was reduced to 69.4±14.0% (n=4) by ECGG in the HEKT2 cells. From these results, EGCG and quercetin represent the first known TREK2 channel inhibitors and only EGCG reduced HEKT2 cell proliferation. This suggests that the flavonoids may work primarily by inhibiting the TREK2 channel, leading to a change in the resting membrane potential, and triggering the initiation of a change in intracellular signaling for cell proliferation. TREK2 channel may, at least in part, contribute to cell proliferation.

TREK-1 채널에 대한 플라보노이드의 효과

김양미(Kim, Yang-Mi),김경아(Kim, Kyung-Ah) 한국산학기술학회 2011 한국산학기술학회논문지 Vol.12 No.6

TREK-1 채널은 two-pore 도메인 포타슘 (K2P) 채널로서 세포내 pH, 세포막의 신전, 불포화 지방산, 온도, 휘발성 마취제, 신경세포방어물질에 의해 잘 조절된다. TREK-1 채널은 포타슘 이동에 의해 신경세포의 흥분성과 안 정막전압을 조절한다. 최근 TREK-1은 전립선 암세포에서도 과발현됨이 확인되었다. 이러한 중요성에도 불구하고, TREK-1 채널에 대한 플라보노이드 효과는 거의 알려지지 않았다. 본 연구의 목적은 전기생리학적 방법 중의 하나인 excised inside-out patch기법을 이용하여 TREK-1 채널을 조절하는 플라보노이드를 탐색하는 것이다. TREK-1 채널이 발현된 CHO 세포에서 단일채널 팻취고정 방법을 이용하여 커큐민 (curcumin), EGCG (epigallocatechin-3-gallate), 퀘르 세틴 (quercetin)에 의한 TREK-1 채널의 차단효과를 증명하였다. 퀘르세틴과 커큐민의 차단효과는 가역적으로 회복되 었으나 EGCG는 거의 회복되지 않았다. 퀘르세틴, EGCG, 커큐민의 상대적 채널 활성도 (relative channel activity)는 73 ± 2.3% (n=5), 91 ± 3.2% (n=7), 94 ± 5.6% (n=4)까지 감소하였다. CHO 세포에 발현된 TREK-1 채널에 대한 커 큐민, 퀘르세틴, EGCG의 IC50는 각각 1.04 ± 0.19 μM, 1.13 ± 0.26 μM, 13.5 ± 2.20 μM 이었다. 이러한 결과는 플 라보노이드가 TREK-1 채널을 억제하며, 이 조절은 신경계 또는 종양세포에서 플라보노이드의 약리학적 작용 중의 하 나임을 제시한다. TREK-1 channel is a member of the two-pore domain potassium (K2P) channel family that is regulated by intracellular pH, membrane stretch, polyunsaturated fatty acids, temperature, and some neuroprotectant agents. TREK-1 channel can influence neuronal excitability by regulating leakage of potassium ions and resting membrane potential. TREK-1 channel has been shown to be overexpressed in prostate cancer cells. Although the importance of these properties, relatively little is known about flavonoid effects in the regulations of TREK-1 channel. The purpose of the study was to screening of flavonoids as the TREK-1 channel modulator using one of electrophysiological techniques such as excised inside-out patch configuration. We demonstrated blocking effect on TREK-1 channel by flavonoids such as epigallocatechin-3-gallate (EGCG), curcumin and quercetin in CHO cells transiently expressing TREK-1 channel. The inhibition of TREK-1 channel by quercetin and curcumin was reversible, whereas EGCG was little reversible. Quercetin, EGCG and curcumin decreased the relative channel activity to 73%, 91% and 94%, respectively. The half-inhibitory concentration (IC50) of curcumin, quercetin and EGCG was 1.04 ± 0.19 μM, 1.13 ± 0.26 μM and 13.5 ± 2.20 μM in CHO cells expressing TREK-1 channel, respectively. These results indicate that flavonoids might regulate TREK-1 and this regulation might be one of the pharmacological actions of flavonoid in nervous systems and cancer cells.

팔, 손가락, 정맥에서 채취한 혈액의 혈당검사결과 비교 분석

김경아(Kim, Kyung-Ah),이인광(Lee, In-Kwang),신은영(Shin, Eun-Young),김양미(Kim, Yang-Mi),김경옥(Kim, Kyoung-Oak),차은종(Cha, Eun-Jong),박경순(Park, Kyung-Soon) 한국산학기술학회 2012 한국산학기술학회논문지 Vol.13 No.4

팔부위에서 혈당을 측정하는 것은 모세혈관에서 혈액을 채취하는 동안 느끼는 통증을 줄일 수 있다. 본 연 구에서는 팔부위 혈당검사의 임상적 유효성을 평가하기 위해 팔부위 혈당검사결과를 손가락 및 정맥에서의 혈당검사 결과와 각각 비교하였다. 당뇨환자 61명이 포함된 555명의 피검자를 대상으로 금식 상태에서 휴대형 혈당계로 손가락 과 팔 안쪽 부위에서 혈당검사를 수행하였으며, 1시간 이내에 피검자 514명의 정맥혈액으로 혈당검사를 수행하였다. 측정값들에 대해 선형회귀분석, 급내 상관분석(intraclass correlation), Passing-Bablok 회귀분석 기법으로 다양하게 비교 분석해 보았다. 팔부위 혈당값은 환자군에서 손가락 및 정맥 혈당값과의 상관계수(r)가 0.97(P<0.0001)로 높은 선형관 계를 나타내었으며, 정상군에서도 r값이 약간 작았지만 유사하였다. 채혈 부위에 따른 혈당값의 평균 차이는 두 집단 에서 모두 ±10mg/dL 이내이었다. 급내 상관계수는 r값에 비교하여 약간 작았지만 두 집단이 유사한 수치를 나타내었 다. Passing-Bablok 분석에서 기울기의 95% 신뢰구간과 절편은 각각 <±20%, <±20mg/dL로서 임상 허용범위 이내의 값을 나타내었다. 본 연구에서 사용한 세 가지 통계분석 결과 팔부위 혈당값이 손가락과 정맥에서 측정한 혈당값과 충분히 일치함이 입증되었다. 팔부위 혈당검사가 표준방법인 손가락 혈당검사와 높은 일치성을 나타내었으므로 금식 상태에서의 임상적용 가능성을 확인할 수 있었다. Capillary blood sampling on the forearm reduces pain caused by skin puncture. The present study compared the blood glucose test results performed at different sampling sites of the forearm, finger, and vein to evaluate clinical validity of this alternative site blood sampling technique. Subjects numbered 555 including 61 diabetic patients participated to measure the glucose concentration on the finger (GF) and the forearm (GA) with a portable glucometer under overnight fasting state. Then, the venous glucose concentration (GV) was measured in 514 subjects in less than 1 hour. The test results were analyzed by simple linear regression, intraclass correlation, and Passing-Bablok regression techniques. GA was highly correlated with GF or GV showing the correlation coefficients (r) of approximately 0.97 (P<0.0001) in the normal group. The patient group also resulted similarly high correlation with only slightly lower r value. The mean differences in glucose concentration were less than ±10mg/dL regardless of the sampling sites. Intraclass correlation coefficients were slightly smaller than r but very much similar in value in both groups. The 95% confidence intervals of the slope as well as the intercept in the Passing-Bablok regression analysis were <±20% and <±20mg/dL, respectively, which were within the clinically acceptable ranges. These three statistical techniques introduced in the present study well demonstrated the consistency of GA with GF and GV. Therefore, the forearm blood glucose test could be considered as clinically valid under fasting condition. Key Words : Blood glucose test, Alternative blood sampling, Comparative analysis

Diazinon이 계배(鷄胚)의 기형 유발에 미치는 효과 I. 계배(鷄胚) 형태와 콜린성 봉쇄약물에 미치는 효과

김종수,김곤섭,김양미,최원영,손성기,허정호,이주홍,Kim, Jong-shu,Kim, Gon-sup,Kim, Yang-mi,Choi, Wong-young,Son, Sung-gi,Heo, Jung-ho,Lee, Ju-hong 대한수의학회 1994 大韓獸醫學會誌 Vol.34 No.1

Teratogenic effects of diazinon were assessed on morphology of chick embryos cholinergic blocking agents. Diazinon at doses ranging from 25 to $2000{\mu}g/egg$, was injected on Day 3 of incubation. $TD_{50S}$, were different for the various teratogenic sings such as wry neck, micromelia, abnormal feathering, abnormal beak and curled claws. The threshold dose for wry neck was higher than the threshold dose for other signs; $40{\mu}g/egg$ produced substantial micromelia, abnormal feathering, abnormal beak and curled claws, but gave no sings of wry neck. In contrast to the teratogenic doses, the $LD_{50}$ of diazinon was very high(above $2000{\mu}g/egg$). One of the characteristics of diazinon-induced teratogenesis was reduction of body weight(78.8%) and body length(73.8%). Maximal teratogenic effects, scored as sings of retarded growth, wry neck, micromelia, abnormal feathering, abnormal beak, and curled claws, were produced when the insectcide was administered on the third or fourth day. The threshold dose for type II teratogenic sings including wry neck and short neck was higher than for type I including micromelia and abnormal feathering. Morphorlogical studies, using atropine and gallamine, suggested that nicotinc but not muscarinic receptors may be involved in the mechanism of diazinon-induced type II malformations.

Xylazine의 진정효과와 α-adrenergic 수용체 봉쇄약물의 길항효과

김충희,하대식,김양미,김종수,Kim, Chung-hui,Hah, Dae-sik,Kim, Yang-mi,Kim, Jong-shu 대한수의학회 1993 大韓獸醫學會誌 Vol.33 No.1

The central nervous system depressant effect of xylazine and xylazine-ketamine was studied in chicken and mice. Intraperitoneal injection of xylazine(1~30 mg/kg) and xylazine(1~30 mg/kg)-ketamine(100 mg/kg) induced a loss of the righting reflex in chicken and mice, respectively. These effects of xylazine were dose-dependent. The results obtained were as follows; 1. The effect of xylazine-induced depression was antagonized by adrenergic antagonists having ${\alpha}_2$-blocking activity(yohimbine, tolazoline, piperoxan and phentolamine). 2. Yohimbine was most effective in the reduction of the CNS depression by xylazine. 3. Phenoxybenzamine and prazosin did not reduced CNS depression by xylazine in both species. 4. Labetalol (${\alpha}_1$, ${\beta}_1$-adrenergic antagonist) and propranolol(${\beta}$-adrenergic blocking agent) were not effective in reducing xylazine induced depression. 5. Cholinergic blocking agents (atropine and mecamylamine), a dopaminergic antagonist (Haloperidol), a histamine $H_1$-antagonist(chlorpheniramine), a histamine $H_2$-antagonist(cimetidine), a serotonergic-histamine $H_1$ antagonist(cyproheptadine) were not effective in reducing xylazine-induced depression. 6. Xylazine-induced depression is mediated by ${\alpha}_2$-adrenergic receptors and appears not to be involved in cholinergic, dopaminergic, serotonergic or histaminergic pathways.

The Biflavonoid Amentoflavone Induces Apoptosis via Suppressing E7 Expression, Cell Cycle Arrest at Sub-G1 Phase, and Mitochondria-Emanated Intrinsic Pathways in Human Cervical Cancer Cells

Sojung Lee,Heejong Kim,Jung-Hee Kim,이동훈,Man-Sub Kim,양영,우은란,김양미,홍진태,강정우,윤도영 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.7

Amentoflavone, a biflavonoid from Selaginella tamariscina, is known to possess several bioactivities such as antitumor, anti-inflammatory, and antifungal effects. However, the mechanism of the anticancer effects of amentoflavone on human cervical cancer cells has not been studied in detail. In this study, we demonstrated that amentoflavone induces apoptosis in SiHa and CaSki cervical cancer cells by suppressing human papillomavirus protein E7 expression. The cyclins and tumor suppressors were modulated by amentoflavone in SiHa and CaSki human cervical cancer cells: cyclin and hyperphosphorylated retinoblastoma (p-pRb) were down-regulated, whereas cyclin-dependent kinase inhibitors and p53 were enhanced. Amentoflavone up-regulated peroxisome proliferator-activated receptor γ (PPARγ) and phosphatase and tensin homolog deleted on chromosome 10 (PTEN) expression levels while inhibiting E7-mediated cyclooxygenase-2 (COX-2)/interleukin-32 (IL-32) expressions were downregulated, and Akt phosphorlylation was decreased in an amentoflavone-induced apoptotic process, suggesting that amentoflavone may be a PPARγ activator. Additionally, the expression of the anti-apoptotic factor Bcl-2 was decreased, whereas that of the well-known apoptotic factor Bax was increased, thereby releasing cytochrome c into cytosol in amentoflavone-treated cervical cancer cells. Furthermore, amentoflavone treatment led to the activation of caspase-3 and -9 and proteolytic cleavage of poly(ADP-ribose) polymerase. The expression level of the extrinsic death receptor Fas (CD95) was not altered by amentoflavone treatment. When these findings are taken together, the biflavonoid amentoflavone activates PPARγ/PTEN expressions and induces apoptosis via suppressing E7 expression, cell cycle arrest at sub-G1 phase, and mitochondria-emanated intrinsic pathways in SiHa and CaSki human cervical cancer cells. These findings suggest that amentoflavone has potential for development as a therapeutic agent for human cervical cancer.

쥐(rats)의 full-thickness skin grafts에 대한 hyperbaric oxygen과 α-tocopherol의 효과

김종수,김충희,김곤섭,하대식,박성근,김양미,Kim, Jong-shu,Kim, Chung-hul,Kim, Gon-sup,Hah, Dae-sik,Park, Sun-gun,Kim, Yang-mi 대한수의학회 2000 大韓獸醫學會誌 Vol.40 No.3

To document that effects of hyperbaric oxygen(HBO) and ${\alpha}-tocopherol$ on full-thickness skin grafts in rat, we performed full-thickness skin grafts bilaterally on each rats. The HBO-treated rats were received HBO twice daily for 90 minutes at 2 ATA. Surgical control rats were not treated with HBO. ${\alpha}-tocopherol$ treated rats were received the agent via oral gastric tube daily for 3 days preoperative and a fourth dose 1 to 2 hours postoperative. HBO plus ${\alpha}-tocopherol$ treated rats were received HBO and ${\alpha}-tocopherol$ as mentioned above. Biopsy specimens were taken from each rat at the time of grafting and on days 2, 4, 7, 10, 14, 21, and 28, then were processed for tissue-concentration of total glutathione(GSHt), oxidized/reduced glutathione level, and thiobarbituric acid-reactive substance(TBARS) levels. The percentage of viable graft on day 10 ranged from 67 to 93%, and was not significantly different among the each other groups. The percentage of viable graft were, however, higher in HBO plus ${\alpha}-tocopherol$ treated rats(78.6%) than in HBO alone treated rats(59.1%), ${\alpha}-tocopherol$ alone treated rats(66.7%) and surgical control rats(58.2%). TBARS concentration had a significant increase from preoperative concentration at day 2, and peak concentration at day 4(p<0.01). Concentration then decreased to preoperative concentration at day 28. GSHt concentration of free skin graft had a similar patteren of change in four groups and decreased significantly from preoperative concentration at day 2, returning to preoperative concentration by day 7(surgical control, HBO-treated, and ${\alpha}-tocopherol-treated$, alone) and 28(HBO plus ${\alpha}-tocopherol-treated$). Percentage of the concentration of reduced glutathione decreased in surgical control, HBO-treated and, ${\alpha}-tocopherol-treated$(p<0.05), and HBO plus ${\alpha}-tocopherol-treared$(p<0.01) on day 7 after surgery, whereas the concentration of oxidized increased significantly in HBO-treated(p<0.05), ${\alpha}-tocopherol-treated$(p<0.05), and HBO plus ${\alpha}-tocopherol-treated$(p<0.01).

심장세포에서 세포내 Ca²⁺ 증가에 의해 활성화되는 Cl^- 통로의 특성과 역할

박춘옥,김양미,한재희,홍성근,Park, Choon-ok,Kim, Yang-mi,Haan, Jae-hee,Hong, Seong-geun 대한수의학회 1994 大韓獸醫學會誌 Vol.34 No.1

The inward tail current after a short depolarizing pulse has been known as Na-Ca exchange current activated by intracellular calcium which forms late plateau of the action potential in rabbit atrial myocytes. Chloride conductance which is also dependent upon calcium concentration has been reported as a possible tail current in many other excitable tissues. Thus, in order to investigate the exsitance of the calcium activated chloride current and its contribution to tail current, whole cell voltage clamp measurement has been made in single atrial cells of the rabbit. The current was recorded during repolarization following a brief 2 ms depolarizing pulse to +40mV from a holding potential of -70mV. When voltage-sensitive transient outward current was blocked by 2 mM 4-aminopyridine or replacement potassium with cesium, the tail current were abolished by ryanodine$(1{\mu}M)$ or diltiazem$(10{\mu}M)$ and turned out to be calcium dependent. The magnitudes of the tail currents were increased when intracellular chloride concentration was increased to 131 mM from 21 mM. The current was decreased by extracellular sodium reduction when intracellular chloride concentration was low(21 mM), but it was little affected by extracellular sodium reduction when intracellual chloride concentration was high(131 mM). The current-voltage relationship of the difference current before and after extracellular sodium reduction, shows an exponential voltage dependence with the largest magnitude of the current occurring at negative potentials, with is similar to current-voltage relationship at negative potentials, which is similar to current-voltage relationship of Na-Ca exchange current. The current was also decreased by $10{\mu}M$ niflumic acid and 1 mM bumetanide, which is well known anion channel blockers. The reversal potentials shifted according to changes in chloride concentration. The current-voltage relationships of the niflumic acid-sensitive currents in high and low concentration of chloride were well fitted to those predicted as chloride current. From the above results, it is concluded that calcium activated chloride component exists in the tail current with Na-Ca exchange current and it shows the reversal of tail current. Therefore it is thought that in the physiologic condition it leads to rapid end of action potential which inhibits calcium influx and it contributes to maintain the low intracellular calcium concentration with Na-Ca exchange mechanism.