• Title/Summary/Keyword: AC Plasma

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Plasma B-type natriuretic peptide (BNP): a useful marker for anthracycline-induced cardiotoxicity in Korean children with cancer (한국인 소아암 환자에서 anthracycline 유발 심독성에 대한 지표로서 BNP 혈장농도의 유용성)

  • Lee, Hyun Dong;Lee, Jae Min;Lee, Yong Jik;Lee, Young Hwan;Hah, Jeong Ok
    • Clinical and Experimental Pediatrics
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    • v.50 no.8
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    • pp.774-780
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    • 2007
  • Purpose : The anthracyclines (AC) are widely used chemotherapeutic agents for pediatric cancers. However, the therapeutic use of these agents is limited by their cardiotoxicity. The aim of the present study was to investigate the usefulness of plasma B-type natriuretic peptide (BNP) levels as a marker for AC-induced cardiotoxicity compared to echocardiography in Korean children with cancer. Methods : Fifty-five pediatric cancer patients who had received chemotherapy including AC were enrolled. The cumulative AC doses, clinical symptoms, and two echocardiography parameters, left ventricular fractional shortening (LVFS) and left ventricular ejection fraction (LVEF), were studied and compared with plasma BNP levels. Results : In 55 patients, plasma BNP levels were measured 115 times and echocardiographies were performed 64 times. The median cumulative dose of AC was $325mg/m^2$ (range 120-600; mean 345) and the median plasma BNP level was 10 pg/mL (range 5-950; mean 31). The cumulative AC doses correlated significantly with the plasma BNP levels (P=0.002). The plasma BNP levels correlated significantly with LVFS (P=0.018) and LVEF (P=0.025). Dilated cardiomyopathies were identified in three patients. LVFS and LVEF decreased and plasma BNP levels increased in a patient with acute dilated cardiomyopathy and in that with symptomatic chronic dilated cardiomyopathy. However, LVFS, LVEF and plasma BNP levels were normal in a patient with asymptomatic chronic dilated cardiomyopathy. Conclusion : The results of this study demonstrated that plasma BNP levels could be used as a marker for AC-induced cardiotoxicity; they showed good correlation with echocardiography findings in pediatric cancer patients. Plasma BNP levels may be used for the detection and management of AC-induced cardiotoxicity in Korean children with cancer.

The Effect of Allium Vegetable Intake on the Redistribution of Pyridoxal 5'-phosphate Levels in Exercising Rats

  • Cho Youn-Ok;Yoon Mi-Kyung
    • Nutritional Sciences
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    • v.8 no.3
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    • pp.169-174
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    • 2005
  • This study investigated the effect of allium vegetable intake on the storage and utilization of energy substrates before, during, and after exercise in tissues of rats. Ninety mts were fed either a control diet or a diet with added allium sativum (AS), allium cepa (AC), allium fistulosum (AF), or allium tuberosum (AT) for 4 weeks and then subdivided into 3 groups: before-exercise (BE) during-exercise (DE) after-exercise (AE). The DE group exercised on treadmill for 1 hour just before being sacrificed at the end of the 4th week of the dietary treatment Rats in the AE group were allowed to recuperate for 2 horns after being exercised like the DE group. Pyriooxal 5'-phospwe (PLP) levels were compared in plasma, liver and skeletal muscle of rats. There was no difference between AS animals and control animals in plasma PLP levels regardless of exercise. The plasma PLP levels of AC animals were higher than those of control animals before exercise but this PLP was decreased with exercise and lower than that of control animals after exercise. The plasma PLP levels of AF animals were higher than those of control animals during exercise but there was no difference before and after exercise. The plasma PLP levels of AT animals were higher than those of control animals regardless of exercise. Compared to those of control mts, the PLP levels of liver and muscle were significantly lower in AS, AC, AF and AT mts before exercise. The levels of liver PLP were significantly decreased in control mts while not changed in AS, AC, AF and AT mts during exercise. The levels of liver PLP tended to decrease in AS, AC and AF mts after exercise. The levels of muscle PLP were significantly decreased in control rats, while not changed in AS, AC and AF mts during exercise. The levels of muscle PLP were decreased in control mts but not changed in AS, AC and AF mts after exercise. Thus, it is suggested that the changes of PLP concentrations in plasma and tissues induced by exercise are affected by allium vegetable diet and demonstrated that allium vegetable intake induced an alteration in the redistribution of PLP among tissues.

Effects of Plasma Lipoproteins on Expression of Vasular Cell Adhesion Molecule- in Human Microvasuclar Endothelial Cells (혈관내피세포에서 Vascular Cell Adhesion Molecule-1 발현에 대한 혈장 지단백의 효과)

  • 박성희
    • Journal of Nutrition and Health
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    • v.31 no.8
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    • pp.1235-1243
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    • 1998
  • Although an elevated plasma level of high density lipoprotein (HDL) is known as a protective component against the development of atherosclerosis and ensuing coronary heart diseases, the related mechanisms are still not established . It has been clearly demonstrated in the early stages of atherogenesis that adhesion of monocytes and lymphocytes to the vascular endothelium is enhanced via adhesion molecules, and that monocytes and macrophages accumulate in the subendothelial space. The present study has investigated whether isolated plasma HDL plays a role in protection against atherogenesis by inhibiting the expression of vascular cell adhesioin molecule-1(VCAM-1) on the endothelial cells. Effects of plasma native low density lipoprotein (LDL) and ac ethylated LDL(AcLDL) on VCAM-1 expression were also examined by using an immunocytochemical technique. While plasma HDL did not alter the basal expression of VCAM-1 , lipopolysaccharide(LPS) induction of this adhesion modlecule was markedly inhibited at a phyaiological concentration of HDL. In contrast, 30$\mu\textrm{g}$ protein/ml AcLDL increased sifnificantly both basal VCAM-1 expression and its LPD induction , suggesting that this modified LDL enhances leukocyte adhesiion to endothelial cells. Unlike AcLDL , plasma native LDL inhibited significantly VCAM-1 expression. This indicates that LDL did not undergo oxidative modificantion while incubated with endothelial cells. These results suggest that plasam HDL may inhibit atherogenesis by reducing the expression of adhesion molecules, which is a protective mechanism independent of tis reverse cholesterol transport function . Modified LDL is a potent iducer for adhesion molecules in vascular endothelical cells and could play a role in the pathogenesis of atherosclerosis by adhering to blood cells.

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Comparison of Operation and Driving Characteristics of Energy Recovery Circuit for an AC Plasma Disaplay Panel (AC Plasma Display Panel용 에너지 회수 회로의 동작과 구동 특성비교)

  • 최병조
    • Proceedings of the KIPE Conference
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    • 2000.07a
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    • pp.674-677
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    • 2000
  • Operational principles and driving characteristics of two well-known energy recovery circuits for ac plasma display panels Weber and Sakai circuits are investigated Efficiency of two circuits is analyzed by comparing the in put current of the circuits with different operating conditions. Driving characteristics of the Weber circuit are studied when the magnitude and pulse width of the driving boltage very.

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Influence of Image Sticking on Electra-Optical Characteristics in Alternating-Current Plasma Display Panels

  • Choi, J.H.;Jung, Y.;Jung, K.B.;Kim, S.B.;Choi, E.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.760-763
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    • 2003
  • We have investigated the electro-optical characteristics of image sticking in AC PDP. Although Image sticking is one of major factors to determine display quality in AC PDP, so far, it has not being reported why it is occurred and how we can prevent it. In this experiment, we have analyzed the effect of MgO protective layer and phosphor on the image sticking and we have measured the difference of firing voltage, brightness and discharge current between sticking image and normal image in AC PDP. As a result, Phosphor degradation is a more major factor than MgO protective layer and the firing voltage of gas discharge in sticking image is higher than that of normal discharge.

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Oxidation of Soot Particles with O Radicals Generated in a AC Streamer Corona Discharge (AC 스트리머 코로나 방전으로 생성된 O 라디칼과 매연 입자의 산화반응)

  • Kim, Pil-Seung;Lee, Kyo-Seung;Hwang, Jung-Ho
    • Journal of the Korean Society of Combustion
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    • v.8 no.1
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    • pp.9-16
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    • 2003
  • Carbon soot emission from combustion processes, especially from diesel engines, is a subject of growing concern since soot is known to seriously affect human health. Efforts have been made to oxidize soot particles utilizing Non-Thermal Plasma(NTP) techniques. When oxygen is carried into a plasma device, electrons generated by the plasma dissociate the oxygen, resulting in the formation of oxygen atoms. These highly activated atoms, called O radicals, are known as strong oxidizing agent. This paper presents concentration variations of CO and $CO_2$ at the exit of the plasma device, resulting from the soot oxidation by O radicals, with variations of inlet oxygen concentration, gas temperature, and gas flow rate. Based on the data, Arrehenious rate constants of reactions between C(s)+O and C(s)+O+O were proposed.

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Spatiotemporal behavior of excited Xe atoms density in Counter discharged type AC-PDP

  • Hong, Young-June;Oh, Phil-Yong;Jeong, Se-Hoon;Hong, Jong-Hwa;Kim, Jung-Hyun;Gyu, Yong;Cho, Seok-Ho;Hong, Sung-Hee;Hong, Byoung-Hee;Choi, Eun-Ha
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08a
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    • pp.574-577
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    • 2007
  • We have measured the excited Xe atoms density in the $1s_5$ metastable states by laser absorption spectroscopy in counter discharged type AC-PDP. This experiment has shown the characteristic of the excited Xe atoms density which is relation to the visible light efficiency of PDP. The density of counter discharged AC-PDP have measured to be $9.47\;{\times}\;10^{13}\;cm{-3}$. The result has been shown to higher value than $1.45\;{\times}\;10^{13}\;cm^{-3}$ of conventional AC-PDP.

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Effect of form of applied current on the formation behavior of PEO films on Al6082 alloy

  • Moon, Sungmo;Kim, Juseok;Shin, Heon-Cheol
    • Journal of the Korean institute of surface engineering
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    • v.55 no.1
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    • pp.9-17
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    • 2022
  • This work is concerned with the formation behavior of PEO (Plasma Electrolytic Oxidation) films on Al6082 alloy under the application of direct current (DC) and alternating current (AC) in an alkaline solution. Arc initiation voltage became much lower by the application of AC than DC, and arc initiation time became shorter under DC than AC. The number of pores present in the PEO films was much larger than that on the surface, irrespective of DC and AC. It was also found that the number of pores in the PEO films formed under AC was more than that under DC and the size of pores is smaller under AC than DC. During the formation of PEO films, a lot of heat was generated and solution temperature increased more rapidly under DC than under AC which is attributed to high PEO film formation voltage under DC than AC.

High Efficient Energy Recovery Circuit for AC Plasma Display Panel (AC Plasma Display Panel 구동 장치의 고효율 전력 회수 회로에 관한 연구)

  • 윤원식;강필순;김철우
    • The Transactions of the Korean Institute of Power Electronics
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    • v.6 no.6
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    • pp.481-488
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    • 2001
  • The sustaining driver for color AC Plasma Display Panel should provide alternating high voltage pulses and recover the energy discharged from the intrinsic capacitance between the scanning and sustaining electrodes inside the panel In this paper a novel efficient energy recovery circuit employing boost-up function is proposed to achieve a faster rise-time and in order to obtain a stable sustain voltage The principle of operation. features simulated results and experiment results are illustrated and verified on a 7.5-inch-panel with 200[kHz]switch frequency.

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