• Journal of the Korean Magnetic Resonance Society
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• v.2 no.1
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• pp.41-49
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• 1998

A linear undecapeptide, Substance P (SP) is involved in a wide variety of physiological processes such as pain, inflammation, salivation, and hypertension. Tertiary structure of SP in dodecylphosphocholine (DPC) micelles has been investigated by CD, NMR spectroscopy, and DGII calculation. CD spectrum of SP in the presence of 7.5 mM DPC micelles does not show any favorable secondary structure. The tertiary structure determined by NMR spectroscopy and DGII calculation shows that the Phe7-Phr8-Gly9-Leu10 region adopts a turn structure, while the N-terminal region is quite flexible. Both prolines in SP exist preferentially as the trans isoforms and the aromatic ring of Phe7 protrudes outward. Conformation of SP may be restrained by the contact of the Phe7 aromatic ring with the hydrophobic side chains of the DPC micelles and this interaction induces a turn structure. Structure of SP in aqueous solution in the presence of DPC micelles can represent a good model to study the conformation recognized by the receptor near neutral membrane.

• Bulletin of the Korean Chemical Society
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• v.21 no.11
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• pp.1085-1089
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• 2000

The effect of 2-hydroxyacetophenone-aroyl hydrazone derivatives on the inhibition of copper corrosion in 3N nitric acid solution at 303 K was investigated by galvanostatic polarization and thermometric techniques. A significant decrease in the cor rosion rate of copper was observed in the presence of the investigated compounds. The corrosion rate was found to depend on the nature and concentrations of the inhibitors. The degree of surface coverage of the adsorbed inhibitors is determined from polarization measurements, and it was found that the results obey the Frumkin adsorption isotherm. The inhibitors acted as mixed-type inhibitors, but the cathode is more polarized. The relative inhibitive efficiency of these compounds has been explained on the basis of structure dependent electron donor properties of the inhibitors and the nature of the metal-inhibitor interaction at the surface. Also, some thermodynamic data for the adsorption process ( ΔGa* and f ) are calculated and discussed.

• Bulletin of the Korean Chemical Society
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• v.9 no.4
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• pp.191-195
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• 1988

The effect of some thiosemicarbazide derivatives on corrosion of aluminium in 2M sodium hydroxide has been studied using thermometric, weight loss and hydrogen evolution techniques. The rate of the corrosion depends on the nature of the inhibitor and its concentration, heated of hydrogenation, mode of interaction with the metal surface and formation of metallic complexes. The compounds are weakly adsorbed on the surface of aluminium and form a monolayer of the adsorbate. Values of the Arrhenius activation energies indicate agreement with those obtained for an activation controlled process.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.4
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• pp.277-286
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• 2006

In the present study, I investigated the effects of N-methyl-D-aspartate (NMDA), arachidonic acid (AA), and Nitric Oxide Synthase Inhibitor (NOS-I), alone or in combination, on the viability of cultured primary normal human oral keratinocytes (NHOK). Specifically, we examined whether AA and NOS-I could protect primary NHOK from glutamate cytotoxicity. The purpose of this study was therefore the preliminary study for the examination of the interaction between these agents and NHOK in order to elucidate the mechanisms by which epithelial growth and regeneration are regulated. NHOK were obtained from gingival tissue of 20 individuals aged 20 to 29, and third passage (P3) cells were used for this study. Cell viability was measured by the MTT assay. NMDA and NNA, a calcium dependent NOS inhibitor, induced an initial increase in cell number, which subsequently decreased by the $7^{th}$ day. Low concentration of AA ($0.5\;{\mu}M$ & $1\;{\mu}M$) induced an increase in cell number while high concentrations of AA ($5\;{\mu}M$ & $10\;{\mu}M$) induced a decrease in cell number. The decrease in cell number induced by NMDA at the $7^{th}$ day was abolished by the addition of low concentrations of AA ($0.5\;{\mu}M$ & $1\;{\mu}M$) or NOS inhibitors. Low concentrations of AA ($0.5\;{\mu}M$ & $1\;{\mu}M$) or NOS inhibitors may protect the NHOK from NMDA induced cytotoxicity. These reactions might be related to the NMDA receptor in the cell and the change of the intracellular calcium ion concentration.

• Molecules and Cells
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• v.23 no.2
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• pp.207-214
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• 2007

lant ${\beta}$-1, 3-glucanases are involved in plant defense and in development. Very little data are available on the expression of rice glucanases both in developmental tissues and under various stresses. In this study, we cloned and characterized twenty-seven rice ${\beta}$-1, 3-glucanases (OsGlu) from at total of 71 putative glucanases. The OsGlu genes were obtained by PCR from a cDNA library and were classified into seven groups (Group I to VII) according to their DNA or amino acid sequence homology. Analysis of the expression of the twenty-seven OsGlu genes by Northern blotting revealed that they were differentially expressed in different developmental tissues as well as in response to plant hormones, biotic stress, high salt etc. OsGlu11 and 27 in Group IV were clearly expressed only in stem and leaf and were also induced strongly by SA (5 mM), ABA ($200{\mu}M$), and M. grisea. OsGlu1, 10, 11, and 14 were induced earlier and to higher levels in incompatible M. grisea interaction than in compatible one. Taken together, our findings suggest that the twenty-seven rice OsGlu gene products play diverse roles not only in plant defense but also in hormonal responses and in development.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.6
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• pp.842-844
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• 2000

Changes in respiration rate (RR), rectal temperature (RT), respiratory moisture loss (RML), packed cell volume (PCV) and haemoglobin (Hb) were monitored in 2 adults female goats each of the Saanen (S) and Toggenburg (T) breeds during 60 min of exercise (walking at 3 km/h) on a moving-belt treadmill on each of 6 alternate days. A significant $time{\times}breed$ interaction was observed for RR; mean values in Sand T after 60 min of exercise were 130 and 223 /min ($p{\leq}0.01$). The observed time x breed interaction for RT indicated that S was less stressed by exercise than T; mean values after 60 min exercise were 40.4 and $40.8^{\circ}C$ respectively ($p{\leq}0.01$). For RML, the $day{\times}breed$ interaction ($p{\leq}0.001$) indicated that while S had higher values on day 1, thereafter the values for T were higher. The $time{\times}breed$ interaction for RML/breath indicated that values for T declined more rapidly (from 9.4 to 3.1 mgjbreath) than those for S (from 8.3 to 4.1 mgjbreath; ($p{\leq}0.01$). PCV declined during exercise ($p{\leq}0.05$) by 5.5 percentage points. The exercise imposed was stressful in that it led to increases in RR, RT and RML. S was most tolerant of exercise in that it recorded lower values of RT. The fact that the RML/breath was higher during exercies in S apparently allowed it to compensate for a lower RR. Despite higher RR and RML, T also had a higher RT, suggesting either higher muscular heat production during exercise in that breed, or higher sweating losses in S.

• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.503-511
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• 2008

An edible marine red alga, Grateloupia filicina, collected from Jeju Island of Korea was hydrolyzed by cheap food-grade carbohydrases (Viscozyme, Celuclast, AMC, Termamyl, and Ultraflo) to investigate its anticoagulant activity. Among the tested enzymatic extracts of G. filicina, a Termamyl extract showed the highest anticoagulant activity. Anion-exchange chromatography on DEAE-cellulose and gel-permeation chromatography on Sepharose-4B were used to purify the active polysaccharide from the crude polysaccharide fraction of G. filicina. The purified sulfated polysaccharide (0.42 sulfate/total sugar) showed ${\sim}1,357kDa$ molecular mass and was comprised mainly of galactose(98%) and 1-2% of glucose. The sample showed potential anticoagulant activity on activated partial thromboplastin time (APTT) thrombin time (TT) assays. The purified G. filicina anticoagulant (GFA) inhibited the coagulation factor X (92%), factor II (82%), and factor VII (68%) of the coagulation cascade, and the molecular interaction (protein-polysaccharide) was highly enhanced in the presence of ATIII (antithrombin III). The dissociation constant of polysaccharide towards serine proteins decreased in the order of FXa (58.9 nM) >FIIa (74.6 nM) >FVII (109.3 nM). The low/less cytotoxicity of the polysaccharide benefits its use in the pharmaceutical industry; however, further studies that would help us to elucidate the mechanism of its activity are needed.

• Korean Journal of Applied Biomechanics
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• v.31 no.3
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• pp.205-213
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• 2021

Objective: The aim of this study was to analyze body stability Joint coordination pattern though as bending stiffness of shoes during stance phase of running. Method: 47 male subjects (Age: 26.33 ± 2.11 years, Height: 177.32 ± 4.31 cm, Weight: 65.8 ± 3.87 kg) participated in this study. All subjects tested wearing the same type of running shoes by classifying bending stiffness (A shoes: 3.2~4.1 N, B shoes: 9.25~10.53 N, C shoes: 20.22~21.59 N). They ran 10 m at 3.3 m/s (SD ±3%) speed, and the speed was monitored by installing a speedometer at 3 m intervals between force plate, and the measured data were analyzed five times. During running, ankle joint, MTP joint, coupling angle, inclination angle (anterior-posterior, medial-lateral) was collected and analyzed. Vector coding methods were used to calculate vector angle of 2 joint couples during running: MTP-Ankle joint frontal plane. All analyses were performed with SPSS 21.0 and for repeated measured ANOVA and Post-hoc was Bonferroni. Results: Results indicated that there was an interaction between three shoes and phases for MTP (Metatarsalphalangeal) joint angle (p = .045), the phases in the three shoes showed difference with heel strike~impact peak (p1) (p = .000), impact peak~active peak (p2) (p = .002), from active peak to half the distance to take-off until take-off (p4) (p = .032) except for active peak~from active peak to half the distance to take-off (p3) (p = .155). ML IA (medial-lateral inclination angle) for C shoes was increased than other shoes. The coupling angle of ankle angle and MTP joint showed that there was significantly difference of p2 (p = .005), p4 (p = .045), and the characteristics of C shoes were that single-joint pattern (ankle-phase, MTP-phase) was shown in each phase. Conclusion: In conclusion, by wearing high bending stiffness shoes, their body instability was increased during running.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.39.4-40
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• 2016

We aim to investigate formation of satellite sub-galactic structures around isolated dwarf galaxies using cosmological hydrodynamic zoom simulations. For this, we modify a cosmological hydrodynamic code, GADGET-3, in a way that includes gas cooling down to T~10K, gas heating by universal reionization when z < 8.9, UV shielding for high density regions of $n_{shield}$ > $0.014cm^{-3}$, star formation in the dense regions ($n_H$ > $100cm^{-3}$), and supernova feedback. To get good statistics, we perform three different simulations for different target galaxies of the same mass of ${\sim}10^{10}M_{sun}$. Each simulation starts in a cubic box of a side length of 1Mpc/h with 17 million particles from z = 49. The mass of dark matter (DM) and gas particle is $M_{DM}=4.1{\times}10^3M_{sun}$ and $M_{gas}=7.9{\times}10^2M_{sun}$, respectively, thus each satellite sub-galactic structure can be resolved with more than hundreds or thousands particles. We analyze total 90 sub-galactic structures that have formed outside of the main halos but infall the main halos. We found that 1) mini halos that interact more with the other mini halos tend to accrete the more mass, 2) mini halos that interact more before the reionization tend to form more stars, 3) mini halos with the more interaction tend to approach closer to the galactic center and have the lower orbital circularity, 4) survivals even in the strong tidal fields evolve baryon dominated system, such as globular clusters.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.52.2-52.2
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• 2013

We explore the relative importance of the role of small-scale environment and large-scale environment in triggering nuclear activity of the local galaxies using a volume-limited sample with $M_r$ < -19.5 and 0.02 < z < 0.0685 selected from the Sloan Digital Sky Survey Data Release 7. The active galactic nuclei (AGN) host sample is composed of Type II AGNs identified with flux ratios of narrow emission lines with S/N > 6 and the central velocity dispersion of the sample galaxies is limited to have a narrow range between 130 < ${\sigma}$ < 200($km\;s^{-1}$), corresponding to 7.4 < $log(M_{BH}/M_{\odot})$ < 8.1 in order to fix the mass of the supermassive black hole at the center of its host galaxy. In this study, we find that the AGN fraction ($f_{AGN}$) of late-type galaxies are larger than of early-type galaxies and that for target galaxy with late-type nearest neighbor, $f_{AGN}$ starts to increase as the target galaxy approaches the virial radius of the nearest neighbor (about a few hundred kpc scale). The latter result may support the idea that the hydrodynamic interaction with the nearest neighbor as well as tidal interaction and merger also plays an important role in triggering the nuclear activity of galaxy. We also find that early-type cluster galaxies show decline of AGN activity compared to ones in lower density regions, whereas the direction of dependence of AGN activity for late-type galaxies is opposite.