• Nuclear Engineering and Technology
• /
• v.52 no.3
• /
• pp.568-574
• /
• 2020

The feasibility of the particle-in-cell (PIC) method is assessed to simulate the non-collective phenomena like non-collective Thomson scattering (TS). The non-collective TS in the laser-plasma interaction, which is related to the single-particle behavior, is simulated through a 2D relativistic PIC code (XOOPIC). For this simulation, a non-collective TS is emitted from a 50-50 DT plasma with electron density and temperature of n_e = 3.00 × 10¹³ cm^-3 and T_e = 1000 eV, typical for the edge plasma at ITER measured by ETS system, respectively. The wavelength, intensity, and FWHM of the laser applied in the ETS system are λ_i,0 = 1.064 × 10^-4 cm, I_i = 2.24 × 10¹⁷ erg=s·㎠, and 12.00 ns, respectively. The electron density and temperature predicted by the PIC simulation, obtained from the TS scattered wave, are n_e,TS = 2.91 × 10¹³ cm^-3 and T_e,TS = 1089 eV, respectively, which are in accordance with the input values of the simulated plasma. The obtained results indicate that the ambiguities rising due to the contradiction between the PIC statistical collective mechanism caused by the super-particle concept and the non-collective nature of TS are resolved. The ability and validity to use PIC method to study the non-collective regimes are verified.

• Proceedings of the Korean Biophysical Society Conference
• /
• 2003.06a
• /
• pp.69-69
• /
• 2003

Human CD99 is a ubiquitous 32-kDa transmembrane protein encoded by the mic2 gene. The major cellular functions of CD99 protein are related to homotypic cell adhension, apoptosis, vesicular protein transport, and differentiation of thymocytes or T cells. Recently it has been reported that expression of a splice variant of CD99 transmembrane protein (Type I and Type II) increases invasive ability of human breast cancer cells. To understand structural basis for cellular functions of CD99 (Type I), we have initiated studies on hCD99$^{TMcytoI}$ and hCD99$^{cytoI}$ using circular dichroism (CD) and multi-dimensional NMR spectroscopy. CD spectrum of hCD99$^{TMcytoI}$ in the presence of 200mM DPC and CHAPS displayed an existence $\alpha$-helical conformation. The solution structure of hCD99$^{cytoI}$ determined by NMR is composed of one N-terminal $\alpha$-helix, $\alpha$A, two C-terminal short $\alpha$-helix segments, $\alpha$B and $\alpha$C. While $\alpha$A and $\alpha$B are connected by the long flexible loop, $\alpha$B and $\alpha$C connected by type III$\beta$-turn. Although it has been rarely figured out the correlation between structure and functional mechanism of hCD99$^{TMcytoI}$ and hCD99$^{cytoI}$, there is possibility of dimerization or oligomerization. In addition, the feasible mechanism of hCD99$^{cytoI}$ is that it could have intramolecular interaction between the N- and C- terminal domain through large flexible AB loop.

• Clinical and Experimental Reproductive Medicine
• /
• v.26 no.1
• /
• pp.1-8
• /
• 1999

In order to study the implantation mechanism various methods for culture of endometrial cells in vitro have been attempted. However, a disadvantage is that primary cultures of stromal and epithelial cells do not have the ability to differentiate, and therefore cannot be reproduced in the same manner as in vivo endometrium. The object of this study is to establish a three dimensional culture of endometrial cells which are both morphologically and functionally identical to in vivo endometrium. Endometrial tissues obtained after hysterectomies were cut into thin slices and treated with collagenase and trypsin-EDTA. The stromal cells and the epithelial cells were separated by centrifugation and cultured for 24 hours in DMEM media containing 10% FCS, 100 nM progesterone, and 1 nM estradiol. The cultured stromal cells were mixed with collagen gel and solidified, after which it was covered with matrigel. Epithelial cells were inoculated on the top and then cultured for 3 days. The three dimensionally cultured endometrial cells were stained for integrin ${\alpha}1,\;{\alpha}4,\;{\beta}3$, and cyclooxygenase-l, -2 by immunohistochemistry, which all showed strong expression. The cultured epithelial cells showed the formation of microvilli, tight junctions and pinopodes by electron microscopy. Studies are currently under way utilizing this three dimensional culture model to ascertain the interaction between the embryo and human endometrial cells at the time of implantation, and it is thought that further studies into a new culture environment which would allow longer periods of culture will be necessary.

• Journal of Microbiology and Biotechnology
• /
• v.10 no.5
• /
• pp.587-594
• /
• 2000

Monoclonal antibodies against glutamate dehydrogenase (GDH) from Sulfolobus solfataricus were produced and characterized using epitope mapping and biosensor technology, Five monoclonal antibodies raised against S. solfataricus GDH were each identified as a single protein band that comigrated with purified S. solfataricus GDH on the SDS-polyacrylamide gel electrophoresis and immunoblot. Epitope mapping analysis showed that only one subgroup among the antibodies tested recognized the same peptide fragments of GDH. Using the anti-S. solfataricus GDH antibodies as probes, the cross-reactivities of GDHs from various sources were investigated and it was found that the mammalian GDH is not immunologically related to S. solfataricus GDH. The structural differences between the microbial and mammalian GDHs were further investigated using biosensor technology (Pharmacia BIAcore) and monoclonal antibodies against S. solfataricus and bovine brain. The binding affinity of S. solfataricus glutamate dehydrogenase anti-S. solfataricus for GDH ($K_D$=11 nM) was much tighter than that of anti-bovine for GDH ($K_D$=450 nM). These results, together with the epitope mapping analysis, suggest that there may be structural differences between the two GDH species, in addition to their different biochemical properties.

• Journal of Chest Surgery
• /
• v.35 no.3
• /
• pp.171-176
• /
• 2002

Background: Blood-foreign interaction cause activation of coagulation and inflammatory process that may lead to multiorgan dysfunction and determine the surgical outcomes. Of the methods for assessing the biocompatibility, the platelet adhesion study is considered as the most valuable evaluation step in blood-foreign interaction. As the most studies have used in-vitro or ex-vivo conditions, we have developed a technique of quantification for platelet adhesion on the blood contact surface by using in-vivo injection of radioactive platelets. Material and Method: A coupled bypass circuit was designed to connect the proximal and descending thoracic aorta in 6 piglets(20∼25 Kg). One side of the circuit tube was consisted of a heparin coated PVC tube(10mm in ID, n=6, Experimental group), and the other, a non-heparin coated PVC tube(10mm in ID, n=6, Control group). After cannulation, the blood was circulated through the circuit for 2 hours. Platelet concentrate was prepared from homologous pig blood 24 hours before the experiment. The platelet concentrate was incubated with Tc-99m-HMPAO for 30 min and then centrifuged for 10 min. The supernatant was discarded and the radio-labeling efficacy was measured. The radio-labeled platelet concentrate was mixed with the autologous plasma to make the volume 5 ml, and the mixture was injected intravenously into the experimental animal. After 2 hour circulation, 5 pieces of the specimen(10mm in length each) were obtained from each PVC tube. The radioisotopes were counted with a gamma counter(Cobra ll, Packard, USA), and the ratio of radioisotope count was compared between the control and experimental group. Result: The radioisotope count number was 537.3221.1 Ci/min in the control group and 311.1 184.5 Ci/min in the experimental group(p=0.0104). The ratio between the groups was 1 to 0.58 (p=0.004). Conclusion: In vivo quantification using technetium-99m-HMPAO labeled platelets is simple and reproducible in evaluating platelet adhesion on a foreign surface. We suggest this technique to be a useful tool for blood compatibility test.

• Asian-Australasian Journal of Animal Sciences
• /
• v.18 no.9
• /
• pp.1310-1319
• /
• 2005

This experiment was conducted to determine the effects of cage density (CD) and humate supplementation (HS) on laying performance, metabolic profile, and egg quality during the peak production period in hens. Lohman layers (n = 180, 46 wks of age) were blocked according to the location of cages and then allocated randomly to two levels of CD (4 or 6 hens per cage or 540 vs. 360 $cm^2$/hen) and three levels of HS (0, 0.15, and 0.30%). Egg production (EP) and feed consumption (FC) were measured daily; egg weight was measured bi-weekly; and BW was measured before and after the experiment. Blood and additional egg samples were obtained at the end of the experiment for determination of metabolic profile and egg quality. The data were analyzed using two-way ANOVA as repeated measures. Except for FC, CD did not affect laying performance parameters. Hens placed in high-density cages had lower FC than hens placed in normal-density cages. Increasing HS level linearly increased FC, EP, and feed conversion ratio (FCR). There was a CD by HS interaction effect on FC and EP. Hens placed in high-density cages had greater serum glucose, total protein, albumin, globulin, Ca, and P concentrations and tended to have greater serum corticosterone concentration than hens placed in normaldensity cages. Increasing HS level linearly increased serum glucose, total protein, albumin, globulin, creatine, and Ca concentrations and linearly decreased serum triglyceride and very low-density lipoprotein concentrations. There was a CD by HS interaction effect on serum glucose and albumin concentrations. There were no alterations in egg quality parameters in response to increasing CD. Albumen index and Haugh unit decreased linearly and other egg quality parameters did not change as HS level increased. In conclusion, increased caging density adversely affected metabolic profile, despite insignificantly deteriorating laying performance. Moreover, benefits from humate supplementation seem to be more noteworthy for hens housed in stressing conditions than for hens housed in standard conditions.

• Journal of Life Science
• /
• v.27 no.6
• /
• pp.673-679
• /
• 2017

Microtubules are long rods in the cytoplasm of cells that plays a role in cell motility and intracellular transport. Microtubule-based transport by motor proteins is essential in intracellular transport. Kinesin 1 is a molecular motor protein that mediates the intracellular transport of various membranous vesicles, mRNAs, and proteins along microtubules. It is comprised of two heavy chains (KHCs, also called KIF5s) and two light chains (KLCs). KIF5s bear a motor domain in their amino (N)-terminal regions and interact with various cargoes through the cargo-binding domain in their carboxyl (C)-terminal regions. To identify proteins interacting with KIF5B, yeast two-hybrid screening was performed, and a specific interaction with the cytoplasmic linker protein 170 (CLIP-170), a plus end microtubule-binding protein, was found. The coiled-coil domain of CLIP-170 is essential for interactions with KIF5B in the yeast two-hybrid assay. CLIP-170 bound to the cargo-binding domain of KIF5B. Also, other KIF5s, KIF5A and KIF5C, interacted with CLIP-170 in the yeast two-hybrid assay. In addition, glutathione S-transferase (GST) pull-downs showed that KIF5s specifically interacted with CLIP-170. An antibody to KIF5B specifically co-immunoprecipitated CLIP-170 associated with KIF5B from mouse brain extracts. These results suggest that kinesin 1 motor protein may transport CLIP-170 in cells.

• Environmental Mutagens and Carcinogens
• /
• v.24 no.1
• /
• pp.15-18
• /
• 2004

There are significant differences in the extent of drug interactions between subjects. The influence of the genetic make up of drug metabolizing enzyme activities (CYP3A5, CYP2C19 and UDP-glucuronosyl transferase) on the pharmacokinetic drug interaction potential were studied in vivo. Nineteen healthy volunteers were grouped with regard to the $CYP3A5^{*}3$ allele, into homozygous wild-type (CYP3A5^{*}1/1^{*}1$, n=6), heterozygous $(CYP3A5^{*}1/^{*}3$, n=6), and homozygous variant-type $(CYP3A5^{*}3/^{*}3$, n=7) subject groups. The pharmacokinetic profile of intravenous midazolam was characterized before and after itraconazole administration (200 mg once daily for 4 days), and also following rifampin pretreatment (600 mg once daily for 10 days), with a washout period of 2 weeks in between. For omeprazole and moclobemide pharmacokinetic interaction study 16 healthy volunteers were recruited. The volunteer group comprised 8 extensive metabolizers and 8 poor metabolizers of CYP2C19, which was confirmed by genotyping. Subjects were randomly allocated into two sequence groups, and a single-blind, placebo-controlled, two-period crossover study was performed. In study I, a placebo was orally administered for 7 days. On the eighth morning, 300 mg of moclobemide and 40 mg of placebo were coadministered with 200 mL of water, and a pharmacokinetic study was performed. During study n, 40 mg of omeprazole was given each morning instead of placebo, and pharmacokinetic studies were performed on the first and eighth day with 300 mg of moclobemide coadministration. In the UGT study pharmacokinetics and dynamics of 2 mg intravenous lorazepam were evaluated before and after rifampin pretreatment (600 mg once daily for 10 days), with a washout period of 2 weeks in between. The subjective and objective pharmacodynamic tests were done before and 1, 2, 4, 6, 8, and 12 hrs after lorazepam administration. The pharmacokinetic profiles of midazolam and of its hydroxy metabolites did not show differences between the genotype groups under basal and induced metabolic conditions. However, during the inhibited metabolic state, the $CYP3A5^{*}3/^{*}3$ group showed a greater decrease in systemic clearance than the $CYP3A5^{*}1/^{*}1$ group $(8.5\pm3.8$ L/h/70 kg vs. $13.5\pm2.7$ L/h/70 kg, P=0.027). The 1'-hydroxymidazolam to midazolam AUC ratio was also significantly lower in the $CYP3A5^{*}3/^{*}3$,/TEX> group $(0.58\pm0.35,$ vs. $1.09\pm0.37$ for the homozygous wild-type group, P=0.026). The inhibition of moclo-bemide metabolism was significant in extensive metabolizers even after a single dose of omeprazole. After daily administration of omeprazole for 1 week, the pharmacokinetic parameters of moclobemide and its metabolites in extensive metabolizers changed to values similar to those in poor metabolizers. In poor meta-bolizers, no remarkable changes in the pharmacokinetic parameters were observed. The area under the time-effect curves of visual analog scale(VAS), choice reaction time, and continuous line tracking test results of lorazepam was reduced by 20%, 7%, 23% respectively in induced state, and in spite of large interindividual variablity, significant statistical difference was shown in VAS(repeated measures ANOVA, p=0.0027).

• Environmental Mutagens and Carcinogens
• /
• v.23 no.4
• /
• pp.131-134
• /
• 2003

There are significant differences in the extent of drug interactions between subjects. The influence of the genetic make up of drug metabolizing enzyme activities (CYP3A5, CYP2C19 and UDP-glucuronosyl transferase) on the pharmacokinetic drug interaction potential were studied in vivo. Nineteen healthy volunteers were grouped with regard to the $CYP3A5^{*}3$ allele, into homozygous wild-type (CYP3A5^{*}1/1^{*}1$, n=6), heterozygous $(CYP3A5^{*}1/^{*}3$, n=6), and homozygous variant-type $(CYP3A5^{*}3/^{*}3$, n=7) subject groups. The pharmacokinetic profile of intravenous midazolam was characterized before and after itraconazole administration (200 mg once daily for 4 days), and also following rifampin pretreatment (600 mg once daily for 10 days), with a washout period of 2 weeks in between. For omeprazole and moclobemide pharmacokinetic interaction study 16 healthy volunteers were recruited. The volunteer group comprised 8 extensive metabolizers and 8 poor metabolizers of CYP2C19, which was confirmed by genotyping. Subjects were randomly allocated into two sequence groups, and a single-blind, placebo-controlled, two-period crossover study was performed. In study I, a placebo was orally administered for 7 days. On the eighth morning, 300 mg of moclobemide and 40 mg of placebo were coadministered with 200 mL of water, and a pharmacokinetic study was performed. During study n, 40 mg of omeprazole was given each morning instead of placebo, and pharmacokinetic studies were performed on the first and eighth day with 300 mg of moclobemide coadministration. In the UGT study pharmacokinetics and dynamics of 2 mg intravenous lorazepam were evaluated before and after rifampin pretreatment (600 mg once daily for 10 days), with a washout period of 2 weeks in between. The subjective and objective pharmacodynamic tests were done before and 1, 2, 4, 6, 8, and 12 hrs after lorazepam administration. The pharmacokinetic profiles of midazolam and of its hydroxy metabolites did not show differences between the genotype groups under basal and induced metabolic conditions. However, during the inhibited metabolic state, the $CYP3A5^{*}3/^{*}3$ group showed a greater decrease in systemic clearance than the $CYP3A5^{*}1/^{*}1$ group $(8.5\pm3.8$ L/h/70 kg vs. $13.5\pm2.7$ L/h/70 kg, P=0.027). The 1'-hydroxymidazolam to midazolam AUC ratio was also significantly lower in the $CYP3A5^{*}3/^{*}3$,/TEX> group $(0.58\pm0.35,$ vs. $1.09\pm0.37$ for the homozygous wild-type group, P=0.026). The inhibition of moclo-bemide metabolism was significant in extensive metabolizers even after a single dose of omeprazole. After daily administration of omeprazole for 1 week, the pharmacokinetic parameters of moclobemide and its metabolites in extensive metabolizers changed to values similar to those in poor metabolizers. In poor meta-bolizers, no remarkable changes in the pharmacokinetic parameters were observed. The area under the time-effect curves of visual analog scale(VAS), choice reaction time, and continuous line tracking test results of lorazepam was reduced by 20%, 7%, 23% respectively in induced state, and in spite of large interindividual variablity, significant statistical difference was shown in VAS(repeated measures ANOVA, p=0.0027).

• Journal of the Korean Chemical Society
• /
• v.42 no.3
• /
• pp.306-314
• /
• 1998

Acetolactate synthase (ALS) is the common enzyme in the biosynthesis of branched chain amino acids, Val, Leu, and Ile in bacteria, yeast, and higher plants. The enzyme is target site of several classes of structually diverse herbicides, including the sulfonylureas, the imidazolinones, the triazolopyrimidines, and the primidyl-oxy-benzoates. We have synthesized new triazolopyrimidine (TP) derivatives, and determined their inhibitory activities on barley ALS. $lC_{50}$ values for the active compounds were 3.2 nM-0.62 mM, and some of them appeared to be potent inhibitors. The progress curves for inhibition of ALS by TP4, a representative derivative, indicated that the extent of inhibition increased with incubation time. The inhibition of ALS by TP4 showed mixed-type inhibition with respect to pyruvate. Dual inhibition analyses of TP4 versus imidazolinone Cadre and feedback inhibitor Leu suggested that three different classes of inhibitors bind to ALS in a mutually exclusive manner. Chemical modification of tyrosyl residues of ALS decreased sensitivity of ALS to TP4, while modification of tryptophan and cysteine did not affect the sensitivity.