• Journal of Korean Neurosurgical Society
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• v.30 no.8
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• pp.963-969
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• 2001

Objectives : Cord blood stem cells have been widely used as donor cells for bone marrow transplantation recently. These cells can give rise to a variety of hematopoietic lineages to repopulate the blood. Recent observations reveal that some bone marrow cells and bone marrow stromal cells(MSCs) can grow to become either neurons or glial cells. It is, however, unclear whether or not there exists stems cells which can differentiate into neurons in the blood during the early stages of postnatal life. Methods : Human cord blood stem cells were prepared from human placenta after full term delivery. To induce neuronal differentiation of stem cells, ${\beta}$-mercaptoethanol was treated. To confirm the neuro-glial characteristics of differentiated stem cells, immunocytochemical stain for NeuN, neurofilament, glial fibrillary acidic protein(GFAP), microtubule associated protein2(MAP2) was performed. RT-PCR was performed for detecting nestin mRNA and MAP2 mRNA. Results : We showed in this experiment that neuro-glial markers(NeuN, neurofilament, MAP2, GFAP) were expressed and axon-like cytoplasmic processes are elaborated in the cultured human cord blood stem cells prepared from new born placenta after full term delivery. Nestin mRNA was also detected in fresh cord blood monocytes. Conclusions : These results suggest that human cord blood derived stem cells may be potential sources of neurons in early postnatal life.

• The Korean Journal of Nuclear Medicine
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• v.26 no.1
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• pp.116-123
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• 1992

$^{123}I$ has ideal half life of 13 hours, suitable 159 keV gamma energy for imaging, and easy labeling methods. In Korea Cancer Center Hospital, $^{123}I$ has been produced by MC-50 cyclotron. The purpose of this study is looking for good labeling condition of $^{123}I$ and $^{99m}Tc$ to nonspecific human polyclonal IgG, and comparing these with $^{67}Ga-citrate$ in the abscess bearing mice. Human polyclonal nonspecific IgG was labeled with 0.2 M phosphate buffer added $^{123}I$ by chloramine T method. Human polyclonat nonspecific IgG was labeled with $^{99m}Tc-gluconate$ after activation with $\beta-mercaptoethanol$. In the abscess bearing mice, the radioactivity in the abscess was higher in 24 hours than 6 hours after injection. In the abscess, $^{123}I$ nonspecific IgG had higher uptake than $^{99m}Tc-IgG\;or\;^{67}Ga-citrate$. There was no significant difference in absecess uptake of $^{123}I-IgG$ among 24, 72, 120 hours abscess age. Further clinical researches with $^{123}I-nonspecific$ IgG, and other immunoscintigraphies using $^{123}I$ are expected.

• Journal of Microbiology and Biotechnology
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• v.19 no.9
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• pp.873-880
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• 2009

A novel xylanase gene, Kxyn, was cloned from Kocuria sp. Mn22, a bacteria isolated from the deep sea of the east Pacific. Kxyn consists of 1,170 bp and encodes a protein of 390 amino acids that shows the highest identity (63%) with a xylanase from Thermohifida fusca YX. The mature protein with a molecular mass of approximately 40 kDa was expressed in Escherichia coli BL21 (DE3). The recombinant Kxyn displayed its maximum activity at $55^{\circ}C$ and at pH 8.5. The $K_m,\;V_{max}$, and $k_{cat}$ values of Kxyn for birchwood xylan were 5.4 mg/ml, $272{\mu}mol/min{\cdot}mg$, and 185.1/s, respectively. Kxyn hydrolyzed birchwood xylan to produce xylobiose and xylotriose as the predominant products. The activity of Kxyn was not affected by $Ca^{2+},\;Mg^{2+},\;Na^+,\;K^+$, ${\beta}$-mercaptoethanol, DTT, or SDS, but was strongly inhibited by $Hg^{2+},\;Cu^{2+},Zn^{2+}$, and $Pb^{2+}$. It was stable over a wide pH range, retaining more than 80% activity after overnight incubation at pH 7.5-12. Kxyn is a cellulase-free xylanase. Therefore, these properties make it a candidate for various industrial applications.

• Korean Journal of Microbiology
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• v.31 no.3
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• pp.230-236
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• 1993

The isocitrate lyase extracted from Micrococcus luteus was purified 38.8 folds with the overall yield of 10.2%, by the ammonium sulfate fractionation, DEAE-cellulose, 1st Sephadex G-200 and 2nd Sephadex G-200 column chromatography. The purified enzyme showed to be a single protein band by polyacrylamide gel electrophoresis. The molecular weight of the purified enzyme was estimated 60,000 by the SDS-polyacry]amide gel electrophoresis. The apparent Michaelis constant, Km value for isocitrate was 0.95 mM. The optimum pH and temperature of the purified enzyme were pH 7.5 and $40^{\circ}C$, respectively. The enzyme was activated by $Mg^{2+}$ and inhibited by $Mn^{2+}$, $Ca^{2+}$, $Cu^{2+}$, $Zn^{2+}$ and $CO^{2+}$. In addition, the activity of isocitrate lyase was increased by glutathione and 2-mercaptocthanol at 5 mM and cysteine at I mM.

• Biomolecules & Therapeutics
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• v.3 no.3
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• pp.205-209
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• 1995

The novel compound KH 3218 was synthesized and evaluated for its ability to inhibit the gastric H$^{＋}$＋ $K^{＋}$ ATPase activity in vitro as well as to lessen gastric acid secretion in vivo. KH 3218 inhibited rabbit gastric H$^{＋}$＋ $K^{＋}$ ATPase in a concentration and time dependent manner. $IC_{50}$/ value was estimated to be about 15 $\mu$M. The inhibition of the H$^{＋}$＋ $K^{＋}$ ATPase by KH 3218 was blocked by sulfhydryl reducing agents, dithiothreitol or $\beta$-mercaptoethanol. The inhibition of the enzyme was not reversible by 50 fold dilution of the incubation mixtures, suggesting the irreversible nature of the inactivation. In the pylorus-ligated rift, KH 3218 reduced the total acid output as compared with the control. In addition, KH 3218 was capable of inhibiting H. pylori urease activity. These data suggest that KH 3218 is a potent inhibitor for H$^{＋}$＋ $K^{＋}$ ATPase activity as well as for gastric acid secretion, and has a potential to be developed as a novel antiulcer agent.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.142-142
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• 2003

본 연구에서는 kiwifruit 과육 속에 들어 있는 단백질분해효소의 gelatin분해활성을 조사하고 그 산업적 방안을 검토하였다. Kiwifruit 과육에서 3개의 단백질분해효소의 활성 밴드(PI, PII, PIII)가 관찰되었다. 단백질분해효소 PI은 220 kD, PII는 51 kD, PIII는 26 kD에 해당하는 것으로 추정할 수 있었다. 이들 단백질분해효소 PI, PII, PIII는 모두 pH 2.0~5.0 범위에서 높은 활성을 보였으며 pH 4.0에서 가장 높게 나타났다. 이들 단백질분해효소 PI, PII, PIII는 모두 cysteine proteinase 저해제인 E-64와 iodoacetate에 의해서 저해되었으며, cysteine proteinase를 촉진하는 DTT, cysteine 및 $\beta$-mercaptoethanol에 의해서 활성이 증가하였다. 그 중 단백질분해효소 PIII는 분자량과 효소의 특성으로 보아 actinidin (EC 3.4.22.14)과 동일한 것으로 판단되었다. 단백질분해효소 PI, PII, PIII는 모두 $Ca^{2+}$, $Mg^{2+}$과 $Mn^{2+}$에 의해 촉진되었으며, $Zn^{2+}$과 Hg$^{2+}$에 의해 완전히 저해되는 것으로 나타났다. 하지만, Co$^{2+}$, Cu$^{2+}$, $Al^{3+}$ , Fe$^{3+}$ 등 금속이온의 영향은 다소 다르게 나타났다. Kiwifruit 과육의 단백질분해효소 PI, PII, PIII 중에서 PI과 PII는 온도가 증가함에 따라 활성이 점차 낮아졌으나 PIII는 비교적 안정한 것으로 조사되었다. 특히, PIII는 5$0^{\circ}C$ 이내의 범위에서 48시간 경과시에도 75% 이상의 활성을 보여 이 범위의 온도에서는 상당 시간 동안 안정한 것으로 나타났다. 단백질분해효소의 산업적 가치를 고려해 볼 때 우선적으로 넓은 기질특이성과 열안정성이 높아야 한다. Kiwifruit에서 추출한 단백질분해효소는 4$0^{\circ}C$ 전후에서 최대의 활성을 보이고, 고온에서도 상당 시간 비교적 안정한 특성을 보여 식품제조, 식육연화 등 식품산업 분야에서의 활용가능성이 높을 것으로 보이며, 나아가 단백질이 갖는 식품학적 기능성을 높이는 데에도 사용할 수 있을 것으로 판단된다.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.606-612
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• 1989

A New lectin from baby clam, Tapes japonica, was isolated and purified through the following procedures; acetone powder, 0.15M NaCl extraction, ammonium sulfate fractionation, N-acetyl-D-galactosamine-agarose affinity column, and ion exchange Mono Q of FPLC. This lectin nonspecifically agglutinated human erythrocytes but didn't agglutinate mouse and rabbit erythrocytes. And the lectin neither stimulated human lymphocytes nor agglutinated Sarcoma 180 cells. On polyacrylamide gel electrophoresis, the lectin migrated as a major single band indicating homogeneous. A molecular weight was estimated to be about 131,000 daltons by Biogel P-300 and 125,000 daltons by SDS-PAGE without ${\beta}-mercaptoethanol$. This lectin is supposed to be a tetramer composed of heterogeneous subunits, about 30,000 and 33,000 daltons. Baby clam lectin was inhibited by EDTA and recovered agglutinating activity by $Ca^{++}\;and\;Mn^{++}$. This lectin is revealed as glycoprotein that contained about 4.2% neutral sugar.

• Journal of Embryo Transfer
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• v.14 no.3
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• pp.185-193
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• 1999

To improve the efficiency of in vitro production of embryos with follicular oocytes in pig, the recovery rates, in vitro fertilization and development. The results obtained were as fellows: The number of oocytes recovered 37 ovary was 1,365 by aspiration, 1,884 by slicing and 3,830 aspiration post slicing, per ovary was averaged 103.5 aspiration post slicing than 30.7 by aspiration and 50.8 by slicing (P<0.05). The percentage of grade I and II oocytes recovered was 0.05∼0.2% and 1.7∼2.3% respectively(p<0.05). The fertilization rates of ejaculate and epididymis sperm was 83.0 and 83.1%. And cleavaged rate was 60.8 and 69.0% respectively(P<0.05). However, there were no significant differences between sperm sources. The clevage rates of fertilized oocyte was significantly(P<0.05) higher as B.O(92.8%) than TALP (90.1%) or mTBM (80.1%). And in vitro developed to blastocyst rates of mTBM media used for fertilization was significantly (P<0.05) higher as 12.4%, compared with the results using the media of TALP(1.6%) or B.O (0.0%). The embryos developed 2-cell stage after in vitro fertilization were co-cultured with or without POEC and BOEC in NCSU-23 and TCM-199 media. In vitro developed to blastocyst rates was NCSU-23 with POEC(2.3%) or BOEC(1.2%), but in vitro cultured in TCM-199 medium with POEC or BOEC was not developed to blastocyst. The percentage of embryos that developed to morula stage in 0, 50, 100, 200 and 250uM was 16.6, 22.0, 13.5, 19.0 and 22.0%, respectively.

• Journal of Embryo Transfer
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• v.12 no.1
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• pp.67-74
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• 1997

This study was carried out to increase the viability of bovine frozen4hawed in vitro produced (IVP) embryos and pregnancy rate by direct transfer method. Cumulus-oocyte complexes were aspirated from excised Hanwoo ovaries and matured in TGM 199 for 20~22 hours at 38.5$^{\circ}C$ in 2% $CO_2$ in air. Matured oocytes were fertilized with capacitated sperm for 6 hours and then co-cultured with cumulus cells for 9 days. 63% of the oocytes cultured was deaved and 29% out of them developed into blastocysts. Good or excellent grade of blastocysts on D 7 or 8 were frozen with 1.8M ethylene glycol as a cryoprotectant for direct transfer. Frozen embryos were thawed at 2$0^{\circ}C$ water for 10 sec following 4~5 second in air. For the survival assay of frozen4hawed lVP blastocysts, they were cultured in TCM 199 supplemented with 100$\mu$M $\beta$-mercaptoethanol and 20% FCS for 72 hours. The percentage of embryos developed to re-expanded or hatched after 72 hours culture was 95. 5 and 77.3%, respectively. When frozen-thawed Ivp embryos were transferred to 43 synchronized recipients by direct transfer method, eighteen recipients (41.8%) was pregnant. The highest pregnant was in naturafly synchronized recipients (71.4%), but induced estrus by using PRID(29.2%) and PGF$_2$$\alpha$(20.0%) was showed lower pregnancy rate. The pregnancy rate was higher in day 7 blastocysts(56.0%) than day 8 blastocysts(22.2%). (Key words: in vitro produced, blastocyst, frozen-thawed, direct transfer)

• Journal of Microbiology and Biotechnology
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• v.22 no.7
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• pp.930-938
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• 2012

High levels of xylanase activity (143.98 IU/ml) produced by the newly isolated Paenibacillus campinasensis G1-1 were detected when it was cultivated in a synthetic medium. A thermostable xylanase, designated XynG1-1, from P. campinasensis G1-1 was purified to homogeneity by Octyl-Sepharose hydrophobic-interaction chromatography, Sephadex G75 gel-filter chromatography, and Q-Sepharose ion-exchange chromatography, consecutively. By multistep purification, the specific activity of XynG1-1 was up to 1,865.5 IU/mg with a 9.1-fold purification. The molecular mass of purified XynG1-1 was about 41.3 kDa as estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Sequence analysis revealed that XynG1-1 containing 377 amino acids encoded by 1,134 bp genomic sequences of P. campinasensis G1-1 shared 96% homology with XylX from Paenibacillus campinasensis BL11 and 77%~78% homology with xylanases from Bacillus sp. YA-335 and Bacillus sp. 41M-1, respectively. The activity of XynG1-1 was stimulated by $Ca^{2+}$, $Ba^{2+}$, DTT, and ${\beta}$-mercaptoethanol, but was inhibited by $Ni^{2+}$, $Fe^{2+}$, $Fe^{3+}$, $Zn^{2+}$, SDS, and EDTA. The purified XynG1-1 displayed a greater affinity for birchwood xylan, with an optimal temperature of $60^{\circ}C$ and an optimal pH of 7.5. The fact that XynG1-1 is cellulose-free, thermostable (stability at high temperature of $70^{\circ}C{\sim}80^{\circ}C$), and active over a wide pH range (pH 5.0~9.0) suggests that the enzyme is potentially valuable for various industrial applications, especially for pulp bleaching pretreatment.