• Title/Summary/Keyword: C-signal

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The Role of Protein Kinase C in Acute Lung Injury Induced by Endotoxin (내독소에 의한 급성폐손상에서 Protein Kinase C의 역할)

  • Kim, Yong-Hoon;Moon, Seung-Hyug;Kee, Sin-Young;Ju, Jae-Hak;Park, Tae-Eung;Im, Keon-Il;Cheong, Seung-Whan;Kim, Hyeon-Tae;Park, Choon-Sik;Jin, Byung-Won
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.2
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    • pp.349-359
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    • 1997
  • Background : The signal pathways and their precise roles for acute respiratory distress syndrome caused by endotoxin (ETX) has not been established. Since there has been several in vitro experiments suggesting that activation of protein kinase C (PKC) pathway may be responsible for endotoxin-induced inflammatory reaction, we performed in vivo experiments in the rats with the hypothesis that PKC-inhibition can effectively prevent endotoxin-induced acute lung injury. Methods : We studied the role of PKC in ETX-induced ALI using PKC inhibitor (staurosporine, STP) in the rat Specific pathogen free male Sprague-Dawley weighted from 165 to 270g were used for the study. Animals were divided into the normal control (NC)-, vehicle control (VC)-, ETX-, PMA (phorbolmyristateacetate)-, STP+PMA-, and STP+ETX-group. PMA (50mg/kg) or ETX (7mg/kg) was instilled through polyethylen catheter after aseptic tracheostomy with and without STP (0.2mg/kg)-pretreatment STP was injected via tail vein 30min before intratracheal injection (IT) of PMA or ETX. Bronchoalveolar lavage (BAL) was done 3-or 6-hrs after IT of PMA or ETX respectively, to measure protein concentration, total and differential cell counts. Results : The results were as follows. The protein concentrations in BALF in the PMA- and ETX-group were very higher than that of VC-group (p<0.001). When animals were pretreated with STP, the %reduction of the protein concentration in BALF was $64.8{\pm}8.5$ and $30.4{\pm}2.5%$ in the STP+PMA- and STP+ETX-group, respectively (p = 0.028). There was no difference in the total cell counts between the PMA-and VC-group (p = 0.26). However the ETX-group showed markedly increased total cell counts as compared to the VC- (p = 0.003) and PMA-group (p = 0.0027), respectively. The total cell counts in BALF were not changed after pretreatment with STP compared to the PMA- (p = 0.22) and ETX-group (p = 0.46). The percentage of PMN, but not alveolar macrophage, was significantly elevated in the PMA-, and ETX-group. Especially in the ETX-group, the percentage of PMN was 17 times higher than that of PMA (p < 0.001). The differential cell counts was not different between the PMA and STP+PMA On the contrary the STP+ETX-group showed decreased percentage of PMN (p = 0.016). There was no significant relationship between the protein concentration and the total or differential cell counts in each group. Conclusion : Pretreatment with PKC-inhibitor (staurosporine) partially but significantly inhibited ETX-induced ALI.

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Rough Set Analysis for Stock Market Timing (러프집합분석을 이용한 매매시점 결정)

  • Huh, Jin-Nyung;Kim, Kyoung-Jae;Han, In-Goo
    • Journal of Intelligence and Information Systems
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    • v.16 no.3
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    • pp.77-97
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    • 2010
  • Market timing is an investment strategy which is used for obtaining excessive return from financial market. In general, detection of market timing means determining when to buy and sell to get excess return from trading. In many market timing systems, trading rules have been used as an engine to generate signals for trade. On the other hand, some researchers proposed the rough set analysis as a proper tool for market timing because it does not generate a signal for trade when the pattern of the market is uncertain by using the control function. The data for the rough set analysis should be discretized of numeric value because the rough set only accepts categorical data for analysis. Discretization searches for proper "cuts" for numeric data that determine intervals. All values that lie within each interval are transformed into same value. In general, there are four methods for data discretization in rough set analysis including equal frequency scaling, expert's knowledge-based discretization, minimum entropy scaling, and na$\ddot{i}$ve and Boolean reasoning-based discretization. Equal frequency scaling fixes a number of intervals and examines the histogram of each variable, then determines cuts so that approximately the same number of samples fall into each of the intervals. Expert's knowledge-based discretization determines cuts according to knowledge of domain experts through literature review or interview with experts. Minimum entropy scaling implements the algorithm based on recursively partitioning the value set of each variable so that a local measure of entropy is optimized. Na$\ddot{i}$ve and Booleanreasoning-based discretization searches categorical values by using Na$\ddot{i}$ve scaling the data, then finds the optimized dicretization thresholds through Boolean reasoning. Although the rough set analysis is promising for market timing, there is little research on the impact of the various data discretization methods on performance from trading using the rough set analysis. In this study, we compare stock market timing models using rough set analysis with various data discretization methods. The research data used in this study are the KOSPI 200 from May 1996 to October 1998. KOSPI 200 is the underlying index of the KOSPI 200 futures which is the first derivative instrument in the Korean stock market. The KOSPI 200 is a market value weighted index which consists of 200 stocks selected by criteria on liquidity and their status in corresponding industry including manufacturing, construction, communication, electricity and gas, distribution and services, and financing. The total number of samples is 660 trading days. In addition, this study uses popular technical indicators as independent variables. The experimental results show that the most profitable method for the training sample is the na$\ddot{i}$ve and Boolean reasoning but the expert's knowledge-based discretization is the most profitable method for the validation sample. In addition, the expert's knowledge-based discretization produced robust performance for both of training and validation sample. We also compared rough set analysis and decision tree. This study experimented C4.5 for the comparison purpose. The results show that rough set analysis with expert's knowledge-based discretization produced more profitable rules than C4.5.

A Study of Characteristics of MicroLion Liquid Ionization Chamber for 6 MV Photon Beam (6 MV 광자빔에 대한 MicroLion 액체이온함의 특성 연구)

  • Choi, Sang-Hyoun;Huh, Hyun-Do;Kim, Seong-Hoon;Ji, Young-Hoon;Kim, Kum-Bae;Kim, Woo-Chul;Kim, Hun-Jeong;Shin, Dong-Oh;Kim, Chan-Hyeong
    • Progress in Medical Physics
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    • v.22 no.4
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    • pp.216-223
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    • 2011
  • Recently PTW developed a MicroLion liquid ionization chamber which is water_equivalent and has a small sensitive volume of $0.002cm^3$. The aim of this work is to investigate such dosimetric characteristics as dose linearity, dose rate dependency, spatial resolution, and output factors of the chamber for the external radiotherapy photon beam. The results were compared to those of Semiflex chamber, Pinpoint chamber and Diode chamber with the sensitive volumes of $0.125cm^3$, $0.03cm^3$ and $0.0025cm^3$, respectively and evaluated to be suitable for small fields. This study was performed in the 6MV photon energy from a Varian 2300 C/D linac accelerator and the MP3 water phantom (PTW, Freiburg) was used. Penumbras in the varios field sizes ranged from $0.5{\times}0.5cm^2$ to $10{\times}10cm^2$ were used to evaluate the spatial resolution. Output factors were measured in the field sizes of $0.5{\times}0.5$ to $40{\times}40cm^2$. Readings of the chamber was linearly proportional to dose. Dose rate dependency was measured from 100 MU/min to 600 MU/min, showed a maximum difference of 5.0%, and outputs decreased with dose rates. The spatial resolutions determined with comparing profiles for the field sizes of $0.5{\times}0.5cm^2$ to $10{\times}10cm^2$ agreed between every detector except the Semiflex chamber to within 2%. Outputs of detectors were compared to that of Semiflex chamber and showed good agreements within 2% for every chamber. This study shows that MicroLion chamber characterized by a high signal-to-noise ratio and water equivalence could be suitable for the small field dosimetry.

Dosimetric Characterization of an Ion Chamber Matrix for Intensity Modulated Radiation Therapy Quality Assurance (세기변조방사선치료 선량분포 확인을 위한 2차원적 이온전리함 배열의 특성분석)

  • Lee, Jeong-Woo;Hong, Se-Mie;Kim, Yon-Lae;Choi, Kyoung-Sik;Jung, Jin-Beom;Lee, Doo-Hyun;Suh, Tae-Suk
    • Progress in Medical Physics
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    • v.17 no.3
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    • pp.131-135
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    • 2006
  • A commercial ion chamber matrix was examined the characteristics and its performance for radiotherapy qualify assurance. The device was the I'mRT 2D-MatriXX (Scanditronix-Wellhofer, Schwarzenbruck, Germany). The 2D-MatriXX device consists of a 1020 vented ion chamber array, arranged in $24{\times}24cm^2$ matrix. Each ion chamber has a volume of $0.08cm^3$, spacing of 0.762 cm and minimum sampling time of 20 ms. For the investigation of the characteristics, dose linearity, output factor, short-term reproducibility and dose rate dependency were tested. In the testing of dose linearity. It has shown a good signal linearity within 1% in the range of $1{\sim}800$cGy. Dose rate dependency was found to be lower than 0.4% (Range: 100-600 Mu/min) relative to a dose rate of 300 Mu/min as a reference. Output factors matched very well within 0.5% compared with commissioned beam data using a ionization chamber (CC01, Scanditronix-Wellhofer, Schwarzenbruck, Germany) in the range of field sizes $3{\times}3{\sim}24{\times}24cm^2$. Short-term reproducibility (6 times with a interval of 15 minute) was also shown a good agreement within 0.5%, when the temperature and the pressure were corrected by each time of measurement. in addition, we compared enhanced dynamic wedge (EDW, Varian, Palo Alto, USA) profiles from calculated values in the radiation planning system with those from measurements of the MatriXX. Furthermore, anon-uniform IMRT dose fluence was tested. All the comparison studies have shown good agreements. In this study, the MatriXX was evaluated as a reliable dosimeter, and it could be used as a simplistic and convenient tool for radiotherapy qualify assurance.

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Microarray profile of hypothalamic gene expression with acupuncture at acupoint ST36 in carrageenan induced inflammation in Stat 6 knockout mice (Carrageenan으로 염증을 유도한 Stat 6 유전자제거 생쥐의 족삼리 침치료에 대한 시상하부 유전자의 마이크로어레이 프로파일)

  • Park, Hi-Joon;Um, Yoon-Kyung;Jung, Kyung-Hee;Kim, Soo-Cheol;Han, Mi-Young;Hong, Mee-Suk
    • Korean Journal of Acupuncture
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    • v.24 no.2
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    • pp.129-139
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    • 2007
  • 목적 : Signal transducers and activators of transcription 6 (Stat 6) 유전자는 면역세포의 발달에 있어서 중요한 유전인자이며, IL-4와 같은 사이토카인에 의해 유전자 발현이 조절된다. 본 연구에서는 Stat 6 유전자 제거 생쥐와 정상 (wild type, W/T) 생쥐에 carrageenan으로 염증을 유도한 후 족삼리에 침치료를 시행하여 시상하부에서의 유전자 발현 양상을 분석하고자 하였다. 방 법 : BALB/c (W/T, n=12) and BALB/c-Stat 6 유전자 제거 생쥐 (n=12)의 발뒤꿈치 표피에 1% carrageenan을 30 ul 주사하여 염증을 유도하였다. 침은 염증 유도 30분 후에 족삼리(ST36)에 시침하였으며, 염증유도에 의한 부종 증가율을 매 시간마다 측정하여 총 5시간동안 측정하였다. 마이크로에러이는 Stat 6 유전자 제거 생쥐를 염증 유발 군과 염증유발 후 침을 처치한 군으로 나누고, 시상하부를 적출하여 RNA를 분리한뒤 마이크로어레이 프로파일을 분석하였다. 결 과 : 염증에 의한 부종증가율을 비교한 결과, Stat 6 유전자 제거 생쥐 그룹의 부종증가율이 W/T 생쥐의 부종 증가율보다 약 50 % 정도 감소하였으며, 각 3, 4, 5시간째에 유의한 차이를 나타내었다. (각 p<0.05). W.T생쥐군과 Stat 6 유전자 제거 생쥐군 모두에서, 침 처치군이 염증 유발 군에 비해, 염증 유발 2시간 후부터 유의한 감소를 나타내었다. 시상하부의 유전자 발현을 관찰한 결과, 39개의 유전자가 3배 이상 감소하였으며, 19개의 유전자는 3배 이상 증가하였다. 결 론 : W/T 생쥐군과 Stat 6 유전자 제거 생쥐 모두에서 침의 진통효과는 나타나며, 이의 기전에는 시상하부에서의 침 치료에 의한 염증관련 유전자들의 감소와, 항염증과 관련된 유전자들이 증가가 관여하는 것으로 보인다., 10, 11), 내측전완피신경(TE5, 6, 7, 8, 9, 10, 11), 후상완피신경(TE12, 13), 상외측상완피신경(TE13), 외측쇄골상신경(TE14, 15),대이개신경(TE16, 17, 18, 19), 소후두신경(TE19, 20), 이개측두신경(TE20, 21, 22), 안면신경측두지(TE22, 23), 관골측두신경(TE23), 중층에 견갑상신경(TE15), 견갑배신경(TE15), 경상설골근신경(TE17), 후이개신경(TE18, 19, 20), 안면신경측두지(TE20, 21, 22), 심층에 후골간신경(TE5, 6, 7), 요골신경심지(TE8, 9, 12, 13), 견갑상신경(TE14), 액와신경가지(TE14), 부신경(TE16), 안면신경과 부신경가지(TE17), 설인신경(TE17), 설하신경(TE17), 경신경고리(TE17), 미주신경(TE17), 안면신경 (TE18). 3) 혈(血) 관(管) : 천층에 척측정맥배측지(TE1, 2), 고유수장지동맥배측지(TE1), 배측중수골동맥배측지(TE2), 배측중수골정맥(TE3), 척측피정맥(TE4, 5, 6, 7, 8, 9, 10, 11), 배측정맥궁(TE4), 부요측피정맥(TE6, 8, 9),요측피정맥(TE10, 11), 후견봉정맥가지(TE13, 14), 후이개동 ${\cdot}$ 정맥(TE16, 17, 18, 19, 20), 전이개동 ${\cdot}$ 정맥(TE20), 천측두동 ${\cdot}$ 정맥(TE22, 23), 중층에 후상완회선동맥(TE14), 견갑배동맥(TE15), 견갑상동맥(TE15),천측두동 ${\cdot}$ 정맥(TE21), 관골측두동 ${\cdot}$ 정맥(TE23), 심층에 배측중수골동맥(TE3), 배측수근동맥궁(TE4), 후골간동맥(TE4, 5, 6, 7, 8, 9), 전골간동맥(TE6, 7, 9)

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Effect of Noise on Density Differences of Tissue in Computed Tomography (컴퓨터 단층촬영의 조직간 밀도차이에 대한 노이즈 영향)

  • Yang, Won Seok;Son, Jung Min;Chon, Kwon Su
    • Journal of the Korean Society of Radiology
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    • v.12 no.3
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    • pp.403-407
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    • 2018
  • Currently, the highest cancer death rate in Korea is lung cancer, which is a typical cancer that is difficult to detect early. Low-dose chest CT is being used for early detection, which has a greater lung cancer diagnosis rate of about three times than regular chest x-ray images. However, low-dose chest CT not only significantly reduces image resolution but also has a weak signal and is sensitive to noise. Also, air filled lungs are low-density organs and the presence of noise can significantly affect early diagnosis of cancer. This study used Visual C++ to set a circle inside a large circle with a density of 2.0, with a density of 1.0, which is the density of water, in which five small circle of mathematics have different densities. Gaussian noise was generated by 1%, 2%, 3%, and 4% respectively to determine the effect of noise on the mean value, the standard deviation value, and the relative noise ratio(SNR). In areas where the density difference between the large and small circles was greatest in the event of 1 % noise, the SNR in the area with the greatest variation in noise was 4.669, and in areas with the lowest density difference, the SNR was 1.183. In addition, the SNR values can be seen to be high if the same results are obtained for both positive and negative densities. Quality was also clearly visible when the density difference was large, and if the noise level was increased, the SNR was reduced to significantly affect the noise. Low-density organs or organs in areas of similar density to cancers, will have significant noise effects, and the effects of density differences on the probability of noise will affect diagnosis.

Relationship between Movements of the Foot and Electromyographic Activities of Lower Leg Muscles in Young Women (젊은 여성의 발동작과 몇몇 하퇴근 근전도와의 관계)

  • Choe, Myoung-Ae;Shin, Dong-Hoon
    • The Korean Journal of Physiology
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    • v.18 no.1
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    • pp.81-96
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    • 1984
  • As the crippled persons work mostly in a sitting position and would be engaged in a foot-pressing job, it is necessary to assess their degree of participation of important muscles in various modes of foot activities. In this regard, it deems to be urgent to establish the reference standards for healthy persons. The present study has been undertaken to determine the degree of participation of the M. tibialis anterior, M. gastrocnemius and M. soleus in heel pressing, foot-flat pressing and forefoot pressing motion under varying forces, and in order to compare the electrical activities of three muscles with each other, and to analyse the time sequence between force and appearance or disappearance of EMG recording. Sixty-three healthy young women ranging from age of 18 to 23 were examined. The results obtained were as follows: 1. Participation of three muscles in foot movement under varying forces: A) Both gastrocnemius muscles or left soleus muscle did not contribute to heel pressing motion. Activity of both tibialis anterior muscles was the greatest among three muscles at heel pressing motion and the degree of their activities was proportional to force. B) Activities of left tibialis anterior muscle and both gastrocnemius muscles were negligible under 3 kg force at foot-flat pressing movement. Left gastrocnemius muscle did not contribute to foot-flat pressing under 6 or 9 kg force. Although activities of both soleus muscles and both tibialis anterior muscles were small, the degree of their activities increased with force at foot-flat pressing movement. C) Activities of both tibialis anterior muscles were negligible under 3 kg force at forefoot pressing motion. Activity of both soleus muscles was the greatest among 3 muscles and the degree of their activities increased with force at forefoot pressing motion. Both tibialis anterior muscles participated in forefoot pressing motion with severe exertion. 2. Electrical activities by foot movement under varying forces : A) Electrical activities were prominent in both tibialis anterior muscles and the level of their activities was linear with force at heel pressing motion. The degree of participation of both soleus muscles was small at heel pressing motion. B) Electrical activity of tibialis anterior muscle was the greatest among 3 muscles at foot-flat pressing movement and was followed by that of soleus muscle. Level of electrical activities increased with force in left soleus muscle and right tibialis anterior muscle at foot-flat pressing movement. C) Electrical activity of both soleua muscles was the greatest among 3 muscles at forefoot pressing movement and that of tibialis anterior muscle was next to soleus muscle. Level of electrical activities was proportional to force in left tibialis anterior muscle, right gastrocnemius muscle and both soleus muscles at forefoot pressing movement. 3. Time between starting signal and initiation of contraction of heel pressing and forefoot pressing motion in 3 muscles was longer than that of foot-flat pressing movement. Time of relaxation in 3 muscles was longer than that of contraction under varying forces. EMG recording appeared before initiation of contraction in both tibialis anterior muscles at heel pressing motion and in both soleus muscles at forefoot pressing movement under varying forces. Time of initiation of contraction was similar in both sides of tibialis anterior muscles under varying forces and time of onset of contraction at foot-flat pressing motion was the shortest. 4. Forefoot pressing movement would be encouraged in paralysis of tibialis anterior muscle, while heel pressing motion would be encouraged in paralysis of triceps surae muscle.

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Effect of Cosmetics Contained Isotonic Water Mimicked Body Fluid on Cell Activities and Skin (생체 모사수 화장품이 세포 활성과 피부에 미치는 효과)

  • Park, Sun Young;Lee, Sung Hoon;Kim, Eun Joo;Choi, So Woong;Kim, Ji Young;Cho, Seong A;Cho, Jun Cheol;Lee, Hae Kwang
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.40 no.2
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    • pp.195-201
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    • 2014
  • Body fluid has been studied for diverse fields like Ringer's solutions, artificial joint fluids, cell growth culture media because it plays a crucial role in controlling body temperature and acts as a solvent for diverse metabolite processes in the body and delivery media of mineral, energy source, hormone, signal and drug from and to cell via blood or lymphatic vessel by osmotic pressure or active uptake. Stratum corneum containing extracellular lipids and NMF (natural moisturizing factor) absorbs atmospheric water residing outside of cells and utilize it to hydrate inside of their own. This process is related to skin barrier function. In this study, we conducted the cell viability test with Cell Bio Fluid $Sync^{TM}$, which mimicks body fluids including amino acids, peptides, and monosaccharides to strengthen skin barrier, and the clinical skin improvement test with cosmetics containing Cell Bio Fluid $Sync^{TM}$. In the cell viability test, HaCaT cell was treated with PBS for 3 hours, followed by the treatment of a cell culture medium (DMEM) and isotonic solution (PBS) and Cell Bio Fluid $Sync^{TM}$ for 3 hours each. Then, MTT assay and image analysis were conducted. In the clinical skin improvement test, twenty-one healthy women participated. Participants applied cosmetics containing Cell Bio Fluid $Sync^{TM}$ on their face for a week and evaluated the skin hydration, skin roughness, brightness and evenness. All measurements were conducted after they washed off their face and took a rest under the constant temperature ($22{\pm}2^{\circ}C$) and constant humidity conditions ($50{\pm}5%$) for 20 minutes. All the data were analyzed by SPSS (version 21) software program. Results showed that Cell Bio Fluid $Sync^{TM}$ improved both the cell viability and in vivo skin conditions such as skin hydration, roughness, brightness and evenness.

In Vitro Phosphorylation of Nuclear Proteins in Isolated Liver Nuclei from Rats Maintained in a Starvation State, Following Refeeding, and from Diabetic Rats with Insulin Injection (단식(斷食), 재급식(再給食) 및 인슈린 투여(投與) 후(後)에 쥐의 간(肝)으로부터 분리된 세포핵의 핵단백질 인산화)

  • Lee, Hyo-Sa;Gibson, David M.
    • Applied Biological Chemistry
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    • v.23 no.1
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    • pp.23-30
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    • 1980
  • Labelling of chromatin proteins with 32P was observed after incubating isolated liver nuclei with $[{\gamma}-32P]$ ATP for 5 minutes at $37^{\circ}C$. The pattern of labelling with 32P was examined on SDS polyacrylamide gel electrophoresis with nuclei from rats maintained in a starvation state for 48 hours, following refeeding for 12 hours; and from fed streptozotocin-diabetic rats with insulin injection 6 hours before sacrifice. With 48h starved rat liver nuclei the level of phosphorylation for 0.14M NaCl soluble proteins was decreased in the molecular weights between 41,000 and 200,000 daltons relative to normal controls. Refeeding the starved rats reversed the change of phosphorylation pattern over 12 hour The level of phosphorylation for five phenol soluble non-histone proteins with molecular weights above 59,000 daltons was somewhat decreased with 48h starved rat liver nuclei as compared with that of normal controls. Starvation also decreased the phosphorylation level of major histones in relation to normal controls. The experiment with insulin injection into fed streptozotocin-diabetic rats showed the tendency to increase phosphorylation of 0.14M NaCl soluble proteins (130,000 dalton protein) and phenol soluble non-histone proteins (155,000 dalton protein). The phosphorylation level of histones appeared to be invariant under the experimental conditoins employed here. These results suggest the possibility that the phosphorylation and dephosphorylation of 0.14M NaCl soluble proteins and $H_1$ histone precede those of other chromatin associated nuclear proteins, It is of interest to find that insulin signal was correlated to phosphorylation of nuclear proteins while glucagon signet dephosphorylated nuclear proteins.

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The Photovoltaic Effect of Iodine-Doped Metal Free Phthalocyanine/ZnO System (Ⅰ) (요오드가 도핑된 무금속 프탈로시아닌/산화아연계의 광기전력 효과(Ⅰ))

  • Heur, Soun-Ok;Kim, Young-Soon;Park, Yoon-Chang
    • Journal of the Korean Chemical Society
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    • v.39 no.3
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    • pp.163-175
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    • 1995
  • Metal free phthalocyanine($H_2Pc$) partially doped with iodine, $H_2Pc(I)x$, has been made to improve photosensitizing efficiency of ZnO/$H_2Pc$. The content of iodine dopant level(x) for $H_2Pc(I)x$ upon $H_2Pc$ polymorphs was characterized as ${\chi}-H_2Pc(I)_{0.92}$ and ${\beta}-H_2Pc(I)_{0.96}$ by elemental analysis. Characterization of iodine-oxidized $H_2Pc$ were investigated by TGA (thermogravimetric analysis), UV-Vis, FT-IR, Raman and ESR (electron spin resonance) spectrum, and the adsorption properties of $H_2Pc(I)x$ on ZnO were characterized by means of Raman and ESR studies. TGA for $H_2Pc(I)x$ showed a complete loss of iodine at approximately 265$^{\circ}C$ and the Raman spectrum of $H_2Pc(I)x$ and ZnO/$H_2Pc(I)x$ at 514.5 nm showed characteristic $I_3^-$ patterns in the frequency region 90∼550 $cm^{-1}$. ZnO/$H_2Pc(I)x$ exhibited a very intense and narrow ESR signal at $g=2.0025{\pm}0.0005$ compared to $H_2Pc$/ZnO. Iodine doped ZnO/$H_2Pc(I)x$ showed a better photosensitivity compared to iodine undoped ZnO/$H_2Pc$. That is, the surface photovoltage of ${\chi}-H_2Pc(I)_{0.92}$/ZnO was approximately 31 times greater than that of ZnO/${\chi}-H_2Pc$ and ZnO/${\beta}-H_2Pc(I)_{0.96}$ was 5 times more efficient than ZnO/${\beta}-H_2Pc$ at 670 nm. And the dependence of photosensitizing effect upon $H_2Pc$ polymorphs was exhibited that the surface photovoltage of ZnO/${\chi}-H_2Pc(I)_{0.92}$ was approximately 5 times greater than ZnO/${\beta}-H_2Pc(I)_{0.96}$ at 670 nm. Therefore Iodine doping of H_2Pc$ resulted in increase in photoconductivity of $H_2Pc$ and photovoltaic effect of ZnO/$H_2Pc$ in the visible region.

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