• Journal of the Optical Society of Korea
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• v.11 no.1
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• pp.26-33
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• 2007

We demonstrate the capability of differential-phase optical coherence tomography (DP-OCT) to detect superparamagnetic iron oxide (SPIO) nanoparticles taken up by liver parenchymeal macrophages (Kupffer cells). We apply an external time-varying high-intensity focused magnetic field. Our experiments demonstrate a novel diagnostic modality to detect macrophages that have taken up SPIO nanoparticles. Magnetic force acting on the nanoparticles was varied by applying a sinusoidal current to a solenoid containing a conical iron core that substantially increased and focused the magnetic field strength ($B_{max}$ = 2 Tesla). $ApoE^{-/-}$ mice were sacrificed 2 days post intravenous injections of different SPIO doses (1.0, and 0.1 mmol Fe/kg body weight). Livers of $ApoE^{-/-}$ mice with and without injection of SPIO nanoparticles were investigated using DP-OCT, which detects tissue movement with nanometer resolution. Frequency response of iron-laden liver movement was twice the stimulus frequency. Movement was not observed in livers of control mice. Results of our experiments indicate DP-OCT is a candidate methodology to detect tissue based macrophages containing SPIO nanoparticles excited by an external focused magnetic field.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.4
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• pp.342-348
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• 2004

Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the $60\%$ isopropanol extract of soybean(Glycine max [L.] Merr.) seed revealed two abundant proteins with molecular masses of 19 and 10 kDa. Amino acid analysis revealed that the isopropanol-extractable protein fraction was rich in cysteine. Two-dimensional gel electro-phoretic analysis indicated that the 19kDa and 10kDa proteins had pI of 4.2 and 4.0 respectively. Peptide mass fingerprints of trypsin digests of the two proteins obtained using matrix-assisted, laser desorption/ionization-time of flight (MALDI-TOF) mass spectroscopy revealed the 19kDa protein was Kunitz trypsin inhibitor and the 10kDa protein was Bowman-Birk proteinase inhibitor. When resolved under non-denaturing conditions, the isopropanol-extracted proteins inhibited trypsin and chymotrypsin activity. Results presented in this study demonstrate that isopropanol extraction of soybean seed could be used as a simple and rapid method to obtain a protein fraction enriched in Kunitz trypsin and Bowman-Birk proteinase inhibitors. Since proteinase inhibitors are rich in sulfur amino acids and are putative anticarcinogens, this rapid and inexpensive isolation procedure could facilitate efforts in nutrition and cancer research.

• Proceedings of the KIEE Conference
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• 2005.11a
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• pp.48-50
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• 2005

As technology is developed, customers want to use many functions in one system. Manufacturers want to reach the customer's needs, make systems more small, thin, light-weight. To make them real, it is necessary to make components to be small and thin. But components of power stage are big, thick and heavy-weighted yet. especially power inductor is the most significant component. This paper proposed a novel chip-type power inductor I-type inductor. Inductor that proposed has 3225-size, 5.6uH and 1.3A of max saturation current. And it has $R_{DC}$ of $0.25{\Omega}$ which is smaller than $0.45{\Omega}$ of chip-type inductor and $0.9{\Omega}$ of coil-type inductor.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.12
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• pp.1742-1746
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• 2014

In order to develop a overhead catenary system for the maximum speed of 400 km/h on Honam high-speed line, increasing tension of contact wire, changing dropper distributions, reducing a hard point and etc. should be considered. And it is also essential to develop core components taking account of the increased tension. Therefore we developed a new steady arm for the max. speed of 400 km/h in this study. FEM (Finite Elements Method) analysis was performed to ensure the strength of the arm. An oval shape was applied to the arm, so that 25 % of strength was increased and 9 % of weight was decreased. And a type test according to the code KRSA-3012 was performed to ensure the performance. Fatigue test in KRRI (Korea Railroad Research Institute)'s test-bed was also performed to evaluate its performance. Some section of the Honam High-speed line was constructed with the developed steady arm.

• BMB Reports
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• v.34 no.4
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• pp.310-315
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• 2001

The uneven distribution of acidic and basic chitinases in different parts of rice seed, and also the characterization of hull-specific chitinases, are reported here. After extraction of chitinases from polished rice, bran, and rice hulls, the chitinases were separated into acidic and basic fractions, according to their behavior on an anion exchanger column. Both fractions from different parts of rice seed showed characteristic activity bands on SDS-PAGE that contained 0.01% glycol chitin. The basic chitinases from rice hulls were further purified using chitin affinity chromatography. The chitinase, specific to rice hulls (RHBC), was 88-fold purified with a 1.3% yield. RHBC has an apparent molecular weight of 22.2 kDa on SDS-PAGE. The optimal pH and temperature were 4.0 and $35^{\circ}C$, respectively. With [$^3H$]chitin as a substrate, RHBC has $V_{max}$ of 13.51 mg/mg protein/hr and $K_m$ of 1.36 mg/ml. This enzyme was an endochitinase devoid of ${\beta}$-1,3-glucanase, lysozyme, and chitosanase activities.

• Journal of Microbiology and Biotechnology
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• v.8 no.3
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• pp.270-276
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• 1998

Extracellular ${\alpha}$-glucosidase was purified to homogeneity from moderately thermophilic Bacillus sp. DG0303. The thermostable ${\alpha}$-glucosidase was purified by ammonium sulfate fractionation, ion-exchange chromatography, preparative polyacrylamide gel electrophoresis (PAGE), and electroelution. The molecular weight of the enzyme was estimated to be 60 kDa by SDS-PAGE. The optimum temperature for the action of the enzyme was at $60^{\circ}C$. It had a half-life of 35 min at $60^{\circ}C$. The enzyme was stable at the pH range of 4.5~7.0 and had an optimum pH at 5.0. The enzyme preparation did not require any metal ion for activity. The thermostable ${\alpha}$-glucosidase hydrolyzed the ${\alpha}$-1,6-linkages in isomaltose, isomaltotriose, and panose, and had little or no activity with maltooligosaccharides and other polysaccharides. The $K_m$ (mM) for p-nitrophenyl-${\alpha}$-D-glucopyranoside (pNPG), panose, isomaltose, and isomaltotriose were 4.6, 4.7, 40.8, and 3.7 and the $V_{max}$(${\mu}mol{\cdot}min^-1$$mg^-1$) for those substrates were 5629, 1669, 3410, and 1827, respectively. The N-terminal amino acid sequence of the enzyme was MERVWWKKAV. Based on its substrate specificity and catalytic properties, the enzyme has been assigned to be an oligo-1,6-glucosidase.

• Journal of Applied Biological Chemistry
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• v.50 no.4
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• pp.196-201
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• 2007

An intracellular invertase was purified to homogeneity from the cell extract of an alkalophilic and thermophilic Bacillus sp. TA-11, which was classified as a new species belonging to Bacillus cereus based on chemotaxanomic and phylogenetic analyses. The purified enzyme with a recovery of 26.6% was determined to be a monomeric protein with a molecular weight of 23 kDa by SDS-PAGE and 26 kDa by gel filtration. The maximum enzyme activity was observed at pH 7.0 and $50^{\circ}C$, and the purified enzyme was stable at the pH range of 5.0 to 8.0 and below $60^{\circ}C$. $K_m$ and $V_{max}$ values of the enzyme for sucrose were 370 mM and 3.0 ${\mu}M$ per min, respectively. The enzyme activity was significantly inhibited by bivalent metal ions ($Hg^{2+}$, $Cd^{2+}$ and $Cu^{2+}$) and sugars (glucose and fructose).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.5
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• pp.566-570
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• 2018

This study determined the acoustic target strength (TS; dB) of black seabream Acanthopagrus schlegeli off the southern coast of Korea. For the ex-situ measurements, 200 kHz split beam transducers were used, and a Kirchhoff-ray mode (KRM) model acoustic model was used for the calculation. The fork length and total weight of the black seabream ranged from 6.4 to 30.8 cm and 6.4 to 683.8 g. respectively 200 kHz, the TS could beexpressed as a function of fork length as: $TS_{max}=20log_{10}(FL)-60.35(R=0.92)$ and $TS_{avg.}=20log_{10}(FL)-66.89(R=0.88)$. These TS results for black seabream can be used for estimating the biomass of fish in acoustic surveys in coastal areas.

• Microbiology and Biotechnology Letters
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• v.23 no.4
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• pp.446-453
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• 1995

$\alpha $-Arabinofuranosidase was produced by E. coli HB101 haboring the recombinant plasmid pKMG11 which contained the arfI gene of Bacillus stearothermophilus. The maximum production of the enzyme was observed when E. coli HB101 cells were grown at 37$\circ$C for 20 hours in the medium containing 0.5% arabinose, 1.0% tryptone, 0.5% yeast extract, and 1% NaCl. The $\ALPHA $-arabinofuranosidase produced was purified to homogeneity using a combination of 20-50% ammonium sulfate precipitation, DEAE-Sepharose CL-6B ion exchange column chromatography and Sepharose 6B-100 gel filtration. The purified enzyme was most active at 55$\circ$C and pH 6.5. The K$_{m}$ and V$_{max}$ values of the enzyme on $\rho $-nitrophenyl-$\alpha $-arabinofuranoside was determined to be 2.99 mM and 0.43 $\mu $mole/min (319.74 $\mu $mole/min/mg), respectively. The pI value was 4.5. The molecular weight of the native protein was estimated to be 289 kDa. The SDS-polyacrylamide gel clectrophoresis analysis suggested that the functional protein was a trimer of the 108 kDa identical subunits. The N-terminal amino acid sequence of the a-arabinofuranosidase was identified as X-Ser-Thr-Ala-Pro-Arg( \ulcorner )-Ala-Thr-Met-Val-Ile-Asp-X-Ala-Phe.

• Archives of Pharmacal Research
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• v.19 no.5
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• pp.423-428
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• 1996

Optimum conditions for hydrolysis were investigated to enhance water-solubilities of protein-bound polysaccharides in the basidiocarps of Ganoderma lucidum by treating chymotrypsin. We also attempted with Ganoderma lucidum residue remaining after extracting hot water-soluble compoents in Ganoderma lucidum. After hydrolyzing under optimum conditions (20 ppm chymotrypsin, 2% Gampderma lucidum or 6% Ganoderma lucidum residue, at pH 10 and at $ 40^{\circ}C$), the amounts of total protein and carbohydrate of hydrolysate were measured. Michaelis constant, $K_{m}$, and maximum rate, $V_{max}$, calculated by Lineweaver-Buck plot for the hydrolysis of Ganoderma lucidum were 1.73% and 0.073%/min respectively and those for hydrolysis of Ganoderma lucidum residue were 2.40% and 0.033%/min respectively. The amount of polysaccharide isolated from Ganoderma lucidum (100 g) treated with chymotrypsin was only 3.07 g, but significantly increased amount (14.34 g) of polysaccharides was isolated from Ganoderma lucidum residue (100 g) treated with chymotrypsin. The protein-bound polysaccharide was isolated from the non-hydrolyzed and hydrolyzed sample and molecular weights of the polysaccharide were measured by Sepharose CL-48 gel filtration.