K - 통로개방제가 배양심근세포와 생쥐 체내의 Thallium - 201 역동학에 미치는 영향

이규보(Kyu Bo Lee),이재태(Jae Tae Lee),안병철(Byeong Cheol Ahn),김은지(Eun Ji Kim),손상균(Kang Kyun Sohn),하정희(Jeoung Hee Ha),김천기(Chun K . Kim) 대한핵의학회 1996 핵의학 분자영상 Vol.30 No.4

N/A Background: Potassium channel opener (K-opener) opens ATP-sensitive K+-channel located at membrane and induces potassium efflux from cytosol, resulting in intracellular hyperpolarization. Newly synthesized K-opener is currently examined for pharmacologic potency by means of rubidium release test from smooth muscle strip pre-incubated with Rb-86. Since in-vive behavior of thallium is similar to that of rubidium, we hypothesized that K-opener can alter T1-201 kinetics in vivo. Purpose: This study was prepared to investigate the effects of pinacidil (one of potent K-openers) on the T1-201 uptake and clearance in cultured myocyte, and in-vivo biodi- stribution in mice. Methods: Spontaneous contracting myocytes were prepared to imitate in-vivo condition from 20 hearts of 3-5 days old Sprague-Dawley rat and cultured for 3-5 days before use (5×105 cells/ml). Pinacidil was dissolved in 10% DMSO solution at a final concentration of 100nM or 10uM and was co-incubated with T1-201 in HBSS buffer for 20-min to evaluate its effect on cellular T1-uptake, or challenged to cell preparation pre-incubated with T1-201 for washout study. Two, 40 or 100μg of pinacidil was injected intravenously into ICR mice at 10 min after 5μCi T1-201 injection, and organ uptake and whole body retention rate were measured at different time points. Results: Co-incubation of pinacidil with T1-201 resulted in a decrease in T1-201 uptake into cultured myocyte by 1.6 to 2.5 times, depending on pinacidil concentration and activity of T1-201 used. Pinacidil enhanced T1-201 washout by 1.6-3.1 times from myocyte preparations pre-incubated with T1-201. Pinacidil treatment appears to be resulted in mild decreases in blood and liver activity in normal mice, in contrast, renal and cardiac uptake were mildly decreased in a dose dependent manner. Whole body retention ratios of T1-201 were lower at 24 hour after injection with 100μg of pinacidil than control. Conclusion: These results suggest that treatment with K-opener may affect the interpretation of T1-201myocardial images, due to decreasing thallium accumulation and enhancing washout from myocardium.

[ $^1H$ ] Nuclear Magnetic Resonance Study of Ferroelectric $(NH_4)_3H(SO_4)_2$

Choi, S.H.,Han, K.S.,Kwon, S.K.,Nam, S.K.,Choi, H.H.,Lee, Moo-Hee,Lim, Ae-Ran Korean Magnetic Resonance Society 2007 Journal of the Korean Magnetic Resonance Society Vol.11 No.2

[ $^1H$ ] nuclear magnetic resonance (NMR) experiments have been performed at 30 - 300 K and 7 T to investigate dynamics of hydrogen bond network in the single crystal $(NH_4)_3H(SO_4)_2$. The two proton sites, ammonium proton and hydrogen-bond proton, are identified from the $^1H$ NMR MAS spectrum at 340 K. As temperature decreases, the $^1H$ NMR spectrum shifts to the higher frequency side with a larger linewidth. The spectrum at 65 K shows a distinctive change in line shape toward the ferroelectric transition at 63 K. The measured values of $T_1$ for ammonium and hydrogen-bond protons are similar in the whole range of temperature. $T_1$ of $^1H$ NMR shows a gradual decrease down to 120 K and starts to steeply increase below 100 K. Then $T_1$ shows abrupt decrease below 70 K with a sharp minimum at 63 K, where the ferroelectric transition occurs. This temperature dependence of spectrum and $T_1$ clearly prove that the large change in the dynamics of hydrogen bond network is associated with the ferroelectric phase transition at 63 K.

조혈모세포이식을 받은 급성 골수 백혈병 환자에서 발생한 cyclosporine에 의한 양측 시신경병증

정진권,김한조,박명진,하승주,최경식,이성진,박성희,이상철,이남수,박희숙,원종호 순천향대학교 의학연구소 2007 Journal of Soonchunhyang Medical Science Vol.13 No.2

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공공정보의 이용활성화 현황분석과 정책제안

이회광(Hee-K때ng Lee),양제민(Jemin Yang),박재천(Jaechon Park) 한국통신학회 2006 한국통신학회 학술대회논문집 Vol.2006 No.11

Block of hERG K⁺ channel and prolongation of action potential duration by fluphenazine at submicromolar concentration

Hong, H.K.,Hoon Lee, B.,Park, M.H.,Ho Lee, S.,Chu, D.,Jin Kim, W.,Choe, H.,Hee Choi, B.,Jo, S.H. North-Holland ; Elsevier Science Ltd 2013 european journal of pharmacology Vol.702 No.1

Fluphenazine is a potent antipsychotic drug that can increase action potential duration and induce QT prolongation in several animal models and in humans. As the block of cardiac human ether-a-go-go-related gene (hERG) channels is one of the leading causes of acquired long QT syndrome, we investigated the acute effects of fluphenazine on hERG channels to determine the electrophysiological basis for its proarrhythmic potential. Fluphenazine at concentrations of 0.1-1.0μM increased the action potential duration at 90% of repolarization (APD<SUB>90</SUB>) and action potential duration at 50% of repolarization (APD<SUB>50</SUB>) in 5min when action potentials were elicited under current-clamp conditions in guinea pig ventricular myocytes. We examined the effects of fluphenazine on hERG channels expressed in Xenopus oocytes and HEK293 cells using two-microelectrode voltage-clamp and patch-clamp techniques. The IC<SUB>50</SUB> for the fluphenazine-induced block of hERG currents in HEK293 cells at 36<SUP>o</SUP>C was 0.102μM at +20mV. Fluphenazine-induced a concentration-dependent decrease of the current amplitude at the end of the voltage steps and hERG tail currents. The fluphenazine-dependent hERG block in Xenopus oocytes increased progressively relative to the degree of depolarization. Fluphenazine affected the channels in the activated and inactivated states but not in the closed states, and the S6 domain mutation from tyrosine to alanine at amino acid 652 (Y652A) attenuated the hERG current block. These results suggest that the antipsychotic drug fluphenazine is a potent blocker of hERG channels, providing a molecular mechanism for the drug-induced arrhythmogenic side effects.

Brillouin Light Scattering Study of the Magnetic Anisotropy in bcc-Fe(100) Ultrathin Films Grown on GaAs(100) Surfaces With Different Reconstructions

Seung-Seok Ha,Nam-Hee Kim,Chun-Yeol You,Sukmock Lee,Ohta, K.,Maruyama, T.,Konishi, K.,Nozaki, T.,Suzuki, Y.,Van Roy, W. IEEE 2009 IEEE transactions on magnetics Vol.45 No.6

<P>We investigated the magnetic anisotropy of ultrathin bcc-Fe (001) films with a fcc-Au(001) cover layer, grown onto GaAs (001) (4 times 1) and (2 times 6)/(3 times 6) reconstructed surfaces. The magneto-optical Kerr effect hysteresis loops revealed existence of a strong in-plane uniaxial magnetic anisotropy in the Fe films grown on both the surfaces. Details of the in-plane uniaxial anisotropy (K<SUB>U</SUB>), cubic anisotropy (K<SUB>C</SUB>), and effective demagnetization field (4piM<SUB>eff</SUB>) were studied by Brillouin light scattering method. We observed a stronger reduction of K<SUB>U</SUB>, K<SUB>C</SUB>, and 4piM<SUB>eff</SUB> in thinner Fe layers (below 1.3 nm) grown on both the surfaces. In the case of Fe films grown on GaAs (4 times 1) surface, anisotropies observed were smaller than that for the (2 times 6)/(3 times 6) surface. This reflects the role of surface structure in determining the magnetic anisotropies.</P>

Aerosol delivery of urocanic acid-modified chitosan/programmed cell death 4 complex regulated apoptosis, cell cycle, and angiogenesis in lungs of K-ras null mice.

Jin, Hua,Kim, Tae Hee,Hwang, Soon-Kyung,Chang, Seung-Hee,Kim, Hyun Woo,Anderson, Hanjo K,Lee, Han-Woong,Lee, Kee-Ho,Colburn, Nancy H,Yang, Hsin-Sheng,Cho, Myung-Haing,Cho, Chong Su American Association for Cancer Research, Inc 2006 Molecular cancer therapeutics Vol.5 No.4

<P>The low efficiency of conventional therapies in achieving long-term survival of patients with lung cancer calls for development of novel treatment options. Although several genes have been investigated for their antitumor activities through gene delivery, problems surrounding the methods used, such as efficiency, specificity, and toxicity, hinder application of such therapies in clinical settings. Aerosol gene delivery as nonviral and noninvasive method for gene therapy may provide an alternative for a safer and more effective treatment for lung cancer. In this study, imidazole ring-containing urocanic acid-modified chitosan (UAC) designed in previous study was used as a gene carrier. The efficiency of UAC carrier in lungs was confirmed, and the potential effects of the programmed cell death protein 4 (PDCD4) tumor suppressor gene on three major pathways (apoptosis, cell cycle, and angiogenesis) were evaluated. Aerosol containing UAC/PDCD4 complexes was delivered into K-ras null lung cancer model mice through the nose-only inhalation system developed by our group. Delivered UAC/PDCD4 complex facilitated apoptosis, inhibited pathways important for cell proliferation, and efficiently suppressed pathways important for tumor angiogenesis. In summary, results obtained by Western blot analysis, immunohistochemistry, and terminal deoxynucleotidyl transferase-mediated nick end labeling assay suggest that our aerosol gene delivery technique is compatible with in vivo gene delivery and can be applied as a noninvasive gene therapy.</P>

Mechanistic insights into the interaction between energetic oxygen ions and nanosized ZnFe₂O₄: XAS-XMCD investigations

Singh, Jitendra Pal,Kaur, Baljeet,Sharma, Aditya,Kim, So Hee,Gautam, Sanjeev,Srivastava, Ramesh Chandra,Goyal, Navdeep,Lim, Weol Cheol,Lin, H.-J.,Chen, J. M.,Asokan, K.,Kanjilal, D.,Won, Sung Ok,Lee, The Royal Society of Chemistry 2018 Physical Chemistry Chemical Physics Vol.20 No.17

<P>The interactions of energetic ions with multi-cation compounds and their consequences in terms of changes in the local electronic structure, which may facilitate intriguing hybridization between O 2p and metal d orbitals and magnetic ordering, are the subject of debate and require a deep understanding of energy transfer processes and magnetic exchange mechanisms. In this study, nanocrystals of ZnFe2O4 were exposed to O<SUP>7+</SUP> ions with an energy of 100 MeV to understand, qualitatively and quantitatively, the metal-ligand field interactions, cation migration and magnetic exchange interactions by employing X-ray absorption fine structure measurements and X-ray magnetic circular dichroism to get deeper mechanistic insights. Nanosized zinc ferrite nanoparticles (NPs) with a size of ∼16 nm synthesized in the cubic spinel phase exhibited deterioration of the crystalline phase when 100 MeV O<SUP>7+</SUP> ions passed through them. However, the size of these NPs remained almost the same. The behaviour of crystal deterioration is associated with the confinement of heat in this interaction. The energy confined inside the nanoparticles promotes cation redistribution as well as the modification of the local electronic structure. Prior to this interaction, almost 42% of Zn<SUP>2+</SUP> ions occupied AO4 tetrahedra; however, this value increased to 63% after the interaction. An inverse effect was observed for metal ion occupancies in BO6 octahedra. The L-edge spectra of Fe and Zn reveal that the spin and valence states of the metal ions were not affected by this interaction. This effect is also supported by K-edge measurements for Fe and Zn. The t2g/eg intensity ratio in the O K-edge spectra decreased after this interaction, which is associated with detachment of Zn<SUP>2+</SUP> ions from the lattice. The extent of hybridization, as estimated from the ratio of the post-edge to the pre-edge region of the O K-edge spectra, decreased after this interaction. The metal-oxygen and metal-metal bond lengths were modified as a result of this interaction, as determined from extended X-ray absorption fine structure measurements. These measurements further support the observation of cation migration from AO4 tetrahedra to AO6 octahedra and <I>vice versa</I>. The Fe L-edge magnetic circular dichroism spectra indicate that Fe<SUP>3+</SUP> ions occupying sites in AO4 tetrahedra and BO6 octahedra exhibited antiferromagnetic-like ordering prior to this interaction. The NPs that interacted with energetic O ions displayed a different kind of magnetic ordering.</P>

몰리브덴인산화물 촉매에 의한 메틸피라진의 가암모니아 산화반응

신채호,장태선,조득희,이동구,이영길 ( Chae Ho Shin,Tae Sun Chang,Deug Hee Cho,Dong Koo Lee,Young K . Lee ) 한국공업화학회 1997 공업화학 Vol.8 No.5

몰리브덴산암모늄염과 인산의 반응으로 P/Mo=0.6의 비율을 가진 몰리브덴인산화물을 제조하고 이를 촉매로 사용하여 메틸피라진의 가암모니아 산화반응에 대한 메틸피라진, 산소, 암모니아의 각각의 분압과 반응온도 등의 반응변수의 영향을 살펴보았다. 표준실험조건하의 반응에서 300시간까지의 촉매활성은 안정상태를 유지하였다. 안정화 상태에서의 메틸피라진의 가암모니아 산화반응 속도식은 -r=kP_MPP_NH3 °P_02^γ(γ=2.2;1.3≤P_02(kPa)≤4)으로 메틸피라진에 대해서는 1차, 암모니아에 대해서는 0차, 산소에 대해서는 분압 4kPa이하에서 2.2차로 나타났다. 623 K이하의 반응온도 하에서의 겉보기 활성화에너지는 29.6㎉/㏖이었다. 메틸피라진의 주생성물은 시아노피라진으로서 선택도는 전환율에 관계없이 항상 90%이상을 유지하였다. Molybdenum phosphate(P/Mo = 0.6) has been synthesized with ammonium molybdate and phosphoric acid under aqueous solution. The kinetics of the ammoxidation of methylpyrazine over molybdenum phosphate catalyst was investigated with the variation of reaction temperature and partial pressure of methylpyrazine, oxygen and ammonia, respectively at atmospheric pressure. The catalytic activity was constant for 300hrs operation under our experimental conditions. Under the steady-state condition, the rate equation of methylpyrazine was shown as -r=kP_MPP_NH3 °P_02^γ(γ=2.2;1.3≤P_02(kPa)≤4). The apparent activation energy was 29.6㎉/㏖ below 623K. The main product obtained in the ammoxidation of methylpyrazine is cyanopyrazine whose selectivity was kept always over 90% regardless of conversion.

수요자 참여형으로 육성된 최고품질 벼 ‘알찬미’

현웅조(Ung-Jo Hyun),원용재(Yong-Jae Won),정응기(Eung-Gi Jeong),안억근(Eok-Keun Ahn),이정희(Jeong-Heui Lee),정국현(Kuk-Hyun Jung),박향미(Hyang-Mi Park),전용희(Yong-Hee Jeon),곽지은(Jieun Kwak),성낙식(Nak-Sig Sung),김정천(Jeong-Cheon K 한국육종학회 2021 한국육종학회지 Vol.53 No.2

Alchanmi’, a japonica rice variety, was developed from a cross between ‘Junam’ and ‘Chilbo’ by a rice breeding team at the NationalInstitute of Crop Science and Icheon, Agricultural Technology Center in 2018. The heading date of ‘Alchanmi’ was August 10 in the middleplain area-two days later than that of ‘Hwaseong’. ‘Alchanmi’ had a culm length of 69 cm, 16 cm shorter than that of ‘Hwaseong’, and 103spikelets per panicle. The viviparous germination rate of ‘Alchanmi’ was 24.4%. It showed resistance to blast, bacterial blight (K1, K2, K3race), and stripe virus, but was susceptible to the K3a race of bacterial blight, dwarf and black streak dwarf viruses, and plant hoppers. Themilled rice of this variety exhibited a translucent and medium short grain shape. The cooked rice grains of ‘Alchanmi’ had an excellent palatabilityindex (0.7) and showed lower amylose content (18.6%) than that of ‘Hwaseong’. The grain milling characteristics of ‘Alchanmi’ were betterthan those of ‘Hwaseong’, especially the head rice milling recovery ratio and head rice ratio (96.2%). ‘Alchanmi’ showed 5.83 MT/ha of milledrice productivity at 6 sites under ordinary cultivation (Registration No. 8132).