• Korean Journal of Clinical Laboratory Science
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• v.50 no.3
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• pp.354-358
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• 2018

When preparing for a blood transfusion, the presence and types of unexpected antibodies should be identified through screening tests. Using the DiaMed-ID system, antibody identification among unexpected antibody screening tests performed at a university hospital in Daejeon area for two years from January 2016 to December 2017 were limited to 55 patients and were predominantly women. A total of 36 patients (65.5%) belonged to the Rh group, 7 (12.7%) patients to the Lewis group, 4 (7.3%) patients to the Kidd and Duffy groups, 3 patients (5.5%) to the MNS group, and 1 (1.8%) to the Rh+Kidd combined group. In the Rh group, 19 (34.5%) patients had Anti-E single antibody, 5 (9.1%) patients had Anti-D single antibody, 4 (7.3%) patients had Anti-E/-c, 4 (7.3%) patients had Anti-C/-e, and 1 (1.8%) patient had $Anti-E/-c/-Jk^b$. In the Lewis group, three (5.5%) patients had both $Anti-Le^a$ and $Anti-Le^b$. In the Kidd group, one (1.8%) patient had $Anti-Jk^a$ and three (5.5%) patients had $Anti-Jk^b$. In the Duffy and MNS groups, only single antibody was found: one (1.8%) patient with $Anti-Fy^a$, three (5.5%) patients with $Anti-Fy^b$, two (3.6%) patients with Anti-M, and one (1.8%) patient with Anti-S. This study reflects the recent frequencies and distributions of unexpected antibodies in Daejeon, which would be helpful for the efficient preparation for transfusions.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2741-2747
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• 2012

A new series of 2,5-disubstituted-1,3,4-thiadiazoles 6a-i was synthesized by overnight stirring various 1,4-disubstituted thiosemicarbazides 5a-i in polyphosphoric acid followed by neutralization. The structures of newly synthesized compounds 5a-i and 6a-i were characterized by IR, $^1H$ and $^{13}C$ NMR, elemental analysis and mass spectrometric studies. All the synthesized compounds were evaluated for their urease and acetylcholine esterase inhibition activities. Thiosemicarbazides 5a-i are found to possess excellent potential for urease inhibition, more than the standard drug. Thiosemicarbazides 5a-i are more potent urease inhibitor than their cyclic analogues thiadiazoles 6a-i. Almost all of the compounds are excellent inhibitors of acetylcholine esterase. The inhibition of acetylcholine esterase of compounds 5a, 5c, 5d, 5g, 5i, 6e, 6f, 6g, and 6i is much more than that of standard drug.

• Journal of the Korean Magnetics Society
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• v.5 no.1
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• pp.58-63
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• 1995

The crystallographic and magnetic properties of the ferrimagnetic $Ni_{0.5}Co_{0.5}Fe_{2}O_{4}$ have been studied by X-ray and $M\"{o}ssbauer$ measurements. The Crystal structure is found to be spinel structure with the lattice constant $a_{0}=8.346{\pm}0.005\;{\AA}$. $M\"{o}ssbauer$ spectra of $Ni_{0.5}Co_{0.5}Fe_{2}O_{4}$ have been taken at various temperatures rallging from 13 to 780 K. The isomer shifts indicate that the valence states of the Fe ions for tetrahedral(A) and octahedral(B) sites have ferric character. Debye temperatures for the A and B sites are found to be $441{\pm}5\;K$ and $321{\pm}5\;K$, respectively. Atomic migration from the A to the B sites starts near 500 K and increases rapidly with increasing temperature to such a degree that 51 % of the ferric ions at the A sites have moved over to the B sites by 700 K.

• Archives of Pharmacal Research
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• v.24 no.5
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• pp.390-396
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• 2001

Synthesized 6-arylamino-5,8-quinolinediones 4a-4j and 6-chloro-7-arylamino-5,8-isoquinolinediones 5a-5g were evaluated for effects on NAD(P)H quinone oxidoreductase (NQOl ) activity with the cytosolic fractions derived from cultured human lung cancer cells and their cytotoxicity in cultured several human solid cancer cell lines. The 5,8-quinolinediones 4 and 5,8-isoquinolinediones 5 affected the reduction potential by NQO1 activity and showed a potent cytotoxic activity against human cancer cell lines. The tested compounds 4a, 5c, 5f, and 5g were considered as more potent cytotoxic agents. The compounds 4d, 5b, 5c, 5e and 5g were comparable modulators of NQO1 activity.

• Proceedings of the IEEK Conference
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• 2000.06b
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• pp.20-23
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• 2000

We have investigated a process for the preparation of high-quality tantalum oxynitride ( $T_{a}$ $O_{x}$ $N_{y}$) via the N $H_3$ annealing of 7$_{a2}$ $O_{5}$, for use in gate dielectric applications. Compared with tantalum oxide (7$_{a2}$ $O_{5}$), a significant improvement in the dielectric constant was obtained by the N $H_3$ treatment. In addition, light reoxidation in a wet ambient at 45$0^{\circ}C$ resulted in a significantly reduced leakage current. We confirmed nitrogen incorporation in the tantalum oxynitride ( $T_{a}$ $O_{x}$ $N_{y}$ by Auger Electron Spectroscopy. By optimizing the nitridation and reoxidation process, we obtained an equivalent oxide thickness as thin as 1.6nm and a leakage current of less than 10mA/$\textrm{cm}^2$ at 1.5V..5V..5V..5V..5V..5V.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.5
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• pp.585-595
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• 2018

Amitriptyline, a tricyclic antidepressant, is commonly used to treat depression and neuropathic pain, but its mechanism is still unclear. We tested the effect of amitriptyline on 5-hydroxytryptamine 3 ($5-HT_3$) receptor currents and studied its blocking mechanism because the clinical applications of amitriptyline overlapped with $5-HT_3$ receptor therapeutic potentials. Using a whole-cell voltage clamp method, we recorded the currents of the $5-HT_3$ receptor when 5-HT was applied alone or co-applied with amitriptyline in cultured NCB-20 neuroblastoma cells known to express $5-HT_3$ receptors. To elucidate the mechanism of amitriptyline, we simulated the $5-HT_3$ receptor currents using Berkeley $Madonna^{(R)}$ software and calculated the rate constants of the agonist binding and receptor transition steps. The $5-HT_3$ receptor currents were inhibited by amitriptyline in a concentration-dependent, voltage-independent manner, and a competitive mode. Amitriptyline accelerated the desensitization of the $5-HT_3$ receptor. When amitriptyline was applied before 5-HT treatment, the currents rose slowly until the end of 5-HT treatment. When amitriptyline was co-applied with 5-HT, currents rose and decayed rapidly. Peak current amplitudes were decreased in both applications. All macroscopic currents recorded in whole cell voltage clamping experiments were reproduced by simulation and the changes of rate constants by amitriptyline were correlated with macroscopic current recording data. These results suggest that amitriptyline blocks the $5-HT_3$ receptor by close and open state blocking mechanisms, in a competitive manner. We could expand an understanding of pharmacological mechanisms of amitriptyline related to the modulation of a $5-HT_3$ receptor, a potential target of neurologic and psychiatric diseases through this study.

• Journal of the Korean Chemical Society
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• v.31 no.1
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• pp.94-97
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• 1987

In a converting reaction of $p-bromo-\alpha-diethylaminoacetophenone$ (1a) and $p-bromo-\alpha-piperidinoacetophenone$ (1b) with KCN and $(NH_4)_2CO_3$, to hydantoin, the expected 5-(p-bromophenyl)-5-diethylaminomethylhydantion (2a) and 5-(p-bromophenyl)-5-piperidinomethylhydantoin (2b) were not formed. Diethylaminomethyl group and piperidinomethyl group were eliminated and p,p'-dibromodiphenylhydantil (4), which might be formed through dimerization of 5-(bromophenyl)-hydantoin (3), and p-bromobenzoic acid (5), which was formed through a degradation of 5-(bromophenyl)-hydantoin, were obtained. In the case of $p-bromo-\alpha-morpholinoacetophenone$ (1c), the expected 5-(p-bromophenyl)-5-morpholinomethylhydantoin (2c) was formed.

• Korean Journal of Materials Research
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• v.30 no.5
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• pp.246-251
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• 2020

The annealing characteristics of cold-rolled Al-6.5Mg-1.5Zn-0.5Fe-0.5Mn alloy, newly designed as an automobile material, are investigated in detail, and compared with those of other aluminum alloys. Using multi-pass rolling at room temperature, the ingot aluminum alloy is cut to a thickness of 4 mm, width of 30 mm, and length of 100 mm to reduce the thickness to 1 mm (r = 75 %). Annealing after rolling is performed at various temperatures ranging from 200 to 500 ℃ for 1 hour. The specimens annealed at temperatures up to 300 ℃ show a deformation structure; however, from 350 ℃ they have a recrystallization structure consisting of almost equiaxed grains. The hardness distribution in the thickness direction of the annealed specimens is homogeneous at all annealing temperatures, and their average hardness decreases with increasing annealing temperature. The tensile strength of the as-rolled specimen shows a high value of 496 MPa; however, this value decreases with increasing annealing temperature and becomes 338 MPa after annealing at 400 ℃. These mechanical properties of the specimens are compared with those of other aluminum alloys, including commercial 5xxx system alloys.

• Bulletin of the Korean Chemical Society
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• v.27 no.6
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• pp.886-892
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• 2006

The interaction between tetraethylammonium chloride (TEACl) with ICl and tetraethylammonium iodide (TEAI) and aza-15-crown-5 (A15C5) with $I_2$ and ICl have been examined spectrophotometrically in acetonitrile solution. The results of TEACl-ICl indicate the formation of $ICl_2$ - through equilibrium reaction. In the case of TEAI-$I_2$ and A15C5-$I_2$, the equilibrium formation of $I_3$ - is confirmed. The interaction of TEAI-ICl begins with the simultaneous production of $I_2$ and IC$I_2$ - (at TEAI/ICl < 0.5) as well as continues with the simultaneous consumption of $I_2$ and formation of I$I_3$ - (at TEAI/ICl > 0.5). Similar behavior is also observed for A15C5-ICl system. However, the changes are seen at A15C5/ICl mole ratios less and more than 0.66. Several equations have been suggested for the formation of detected species. The formation constants of various reactions were evaluated from the computer fitting of the absorbance-mole ratio data. IR spectra of A15C5 and 1:1 A15C5:ICl or A15C5:$I_2$ complexes are compared and the effect of complexation on absorption bands is discussed.

• Journal of Ceramic Processing Research
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• v.21 no.1
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• pp.5-13
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• 2020

(K0.5Na0.5)NbO3-based ceramic powders for lead-free piezoelectric applications are usually prepared by solid state synthesis. This generally involves wet ball milling in an organic liquid such as ethanol, which is a drawback for industrial production. In the present work, a method for the preparation of NaNbO3 nanopowders is modified to produce a simple method of preparing (K0.5Na0.5)NbO3 nanopowders by an aqueous route. K2CO3, Na2CO3 and NH4[NbO(C2O4)2].xH2O are mixed in water and dried to form a gel, which is then calcined at temperatures between 400 ~ 650 ℃ for 1 h. The uncalcined gel and calcination products are analysed using Thermogravimetric Analysis/Differential Thermal Analysis, X-ray Diffraction, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, Transmission Electron Microscopy and Raman Scattering. A single phase tetragonal (K0.5Na0.5)NbO3 nanopowder with a particle size of ~ 30 nm can be produced after calcination at 650 ℃ for 1 h.