• Korean Membrane Journal
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• v.1 no.1
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• pp.25-37
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• 1999

positron annihilation Lifetime Spectroscopy has been extensively applied in recent years to investigate the free volume in polymers owing to the capability of the electron-positron bound system (positronium) to probe the typical size of sub-nanometric cavities among the macromolecular chains. In this paper we show recent results obtained through this technique in some amorphous polymeric mem-branes(olyurethanes. PUs and polytrimethilsylilpropine PTMSP) after a brief survey of the general features of the annihilation process as well as of the experimental apparatus. Lifetime of o-ps decay({{{{ tau _3}}}}) in PUs increases going from sub {{{{ TAU _g}}}} to over {{{{ TAU _g}}}} temperatures following a sigmoid curve. The coefficient of dilatation of the free volume fraction is shown to be the sum of two contributes due to the variation with T of the number of holes and of their mean volume. PAL spectrum of PTMSP freshly prepared shows four lifetime components: {{{{ tau _3}}}} and {{{{ tau _4}}}}: only are useful for free volume study. Two kinds of holes of different equivalent radius are reported ({{{{ gamma _s}}}} 4.60 nm and {{{{ gamma _1}}}} 0.754) The equivalent volume does not change in a range of 100 K. however the physical aging increases density and decreases oxygen permeability while {{{{ gamma _s}}}} goes down to 0.374 and r1 to 0.735 The number of holes obtained from the intensities{{{{ IOTA _3}}}} and {{{{ IOTA _4}}}} of PAL spectra decreases with aging 21.7% and 3.5% for large and small holes respectively.

• Preventive Nutrition and Food Science
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• v.8 no.4
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• pp.390-394
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• 2003

In the post-genome period, the technique for identifying gene expression has been progressed to high throughput screening. In the field of molecular nutrition, the use of screening techniques to clarify molecular function of specific nutrients would be very advantageous. In this study, we have evaluated Zn-regulated gene expression in Zn-deficient, homocystein-treated EA.hy926 cells, using cDNA microarray, which can be used to screen the expression of many genes simultaneously. The information obtained can be used for preliminary assessment of molecular and signaling events modulated by Zn under pro-atherogenic conditions. EA.hy926 cells derived from human umbilical vein endothelial cells were cultured in Zn-adequate (control, 15 $\mu$M Zn) or Zn-deficient (experimental, 0 $\mu$M Zn) Dulbecco's MEM media under high homocysteine level (100 $\mu$M) for 3 days of post-confluency. Cells were harvested and RNA was extracted. Total RNA was reverse-transcribed and the synthesized cDNA was labeled with Cy3 or Cy5. Fluorescent labeled cDNA probe was applied to microarray slides for hybridization, and the slide was then scanned using a fluorescence scanner. The expression of seven genes was found to be significantly decreased, and one significantly increased, in response to treatment of EA.hy926 cells with Zn-deficient medium, compared with Zn-supplemented medium. The upregulated genes were oncogenes and tumor suppressor genes, cell cycle-related genes and transporter genes. The down-regulated gene was RelB, a component of the NF-kappaB complex of transcription factors. The results of this study imply the effectiveness of cDNA microarray for expression profiling of a singly nutrient deficiency, namely Zn. Furthur study, using tailored-cDNA array and vascular endothelial cell lines, would be beneficial to clarify the molecular function of Zn in atherosclerosis, more in detail.

• Restorative Dentistry and Endodontics
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• v.26 no.4
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• pp.285-295
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• 2001

The objective of this study was to investigate the inhibitory effect of taurine and alendronate on the osteoclast differentiation. Osteoblasts and bone marrow cells from 1-2 day old mouse were co-cultured in 10% fetal bovine serum - minimal essential media (FBS-MEM). Osteoclast differentiation was induced by adding the sonicated extracts of Porphyromonas gingivalis (P.gingivalis). Osteoclasts were identified using tartrate resistant acid phosphotase staining (TRAP). Alendronate of 10$^{-7}$, 10$^{-6}$, 10$^{-5}$M and taurine of 500, 1000, 1500$\mu\textrm{g}$/ml were added respectively. The cytotoxic effects of alendronate and taurine were examined using MTT(3-(4,5-dimethylthiazol -2-yl-2,5-diphenyltetrazo- lium bromide) method. After culturing with the sonicated extracts of P.gingivalis, the amounts of IL-6 in the culture supernatant were measured and compared using the ELISA method. The results were as follows : 1. Osteoclasts were differentiated at the concentration of 0.01~0.1$\mu\textrm{g}$/ml sonicated extracts of P.gingivalis. (P<0.05). 2. Alendronate inhibited osteoclasts differentiation at the concentration of 10$^{-5}$ M when the concentration of sonicated extracts of P.gingivalis was 0.01$\mu\textrm{g}$/ml. 3. Taurine inhibited osteoclasts differentiation at the concentration of 1500$\mu\textrm{g}$/ml when the concentration of sonicated extracts of P.gingivalis 0.01$\mu\textrm{g}$/ml. 4. In cytotoxic test (MTT test), no cytotoxic effect was evident in all concentrations of alendronate and taurine. 5. Taurine (10$^{-5}$M) and alendronate(1500$\mu\textrm{g}$/ml) did not change the amounts of IL-6 induced by sonicated extracts of P.gingivalis significantly.

• The Journal of Korean Obstetrics and Gynecology
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• v.18 no.4
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• pp.10-23
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• 2005

Purpose : This study is to examine the ability of Rhizoma Scirpi (RS) to induce HeLa cell viability. Methods : We culture HeLa cell which is human metrocarcinoma cell in D-MEM included 10% fetal bovine serum(Hyclone Laboratories) below $37^{\circ}C$, 5% CO2. Then we observed apoptosis of log phage cell which is changed cultivation liquid 24 Hours periodically. Results : 1. RS induces mitochondria membrane potential collapse. 2. P38 MAPK is involved in RS-induced death in HeLa cells. 3. P38 MAPK is involved in RS-induced apoptosis in HeLa cells. 4. P38 MAPK reguates RS-induced caspase-3, -8 and -9 activation in HeLa cells. 5. The inhibition of caspase regulates RS-induced cell death in HeLa cells. 6. RS induces mitochondria membrane potential collapse in HeLa cells. 7. P38 MPK is involved in the regulation of Bcl-2 and Bfu in HeLa cells.8. RS regulates the expression of Bcl-2 and Bax in HeLa cells. 9. SR induces p38 MAPK activation in HeLa cells. Conclusion : RS induces apoptosis in HeLa cells via p38 MAPK activation.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.1
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• pp.67-74
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• 2002

A phosphor for Plasma Display Panel, BaMgAl$_{10}$ O$_{17}$ :Eu$^{2+}$, showing a blue emission band at about 450nm was prepared by a solid-state reaction using BaCO$_3$, $Al_2$O$_3$, MgO, Eu$_2$O$_3$ as starting materials wish flux AlF$_3$. The study of the behaviour of Eu in BAM phosphor was carried out by the photoluminescence spectra and the Rietveld method with X-ray and neutron powder diffraction data to refine the structural parameters such as lattice constants, the valence state of Eu, the preferential site of Mg atom and the site fraction of each atom. The phenomenon of the concentration quenching was abound 2.25~2.3wt% of Eu due to a decrease in the critical distance for energy transfer of inter-atomic Eu. Through the combined Rietveld refinement, R-factor, R$_{wp}$, was 8.11%, and the occupancy of Eu and Mg was 0.0882 and 0.526 at critical concentration. The critical distance of Eu$^{2+}$ in BAM was 18.8$\AA$ at 2.25% Eu of the concentration quenching. Furthermore, c/a ratio was decreased to 3.0wt% and no more change was observed over that concentration. The maximum entropy electron density was found that the modeling of $\beta$-alumina structure in BaMgAl$_{10}$ O$_{17}$ :Eu$^{2+}$correct coincided showing Ba, Eu, O atoms of z= 1/4 mirror plane.e.ane.e.

• Macromolecular Research
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• v.15 no.5
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• pp.412-417
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• 2007

In the present study, crosslinked poly(vinyl alcohol) (PVA) membranes were prepared at different temperatures using poly(styrene sulfonic acid-co-maleic acid) (PSSA_MA) (PVA:PSSA_MA = 1:9). The hybrid mem-branes were prepared by varying the TEOS content between 5 and 30 wt%. The PSSA_MA was used both as a crosslinking agent and the hydrophilic group donor ($-SO_3H$ and/or-COOH). The proton conductivity increased with up to 20 wt% TEOS, but decreased above this level, although the water content decreased with increasing TEOS content. This result suggests that the silica doped into the membrane improved the formation of proton-conduction pathways due to the absorption of molecular water. The PVA/PSSA_MA/Silica containing TEOS 20% showed both high proton conductivity (0.026 S/cm at $90^{\circ}C$) and low methanol permeability ($5.55{\times}10^{-7}cm^2/s$).

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.809-819
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• 1996

This study was conducted to identify the effects of caffeine or combinations of caffeine and iron or vitamin E on the lipid and protein components in the MDBK(Mardin-Darby Bovine Kidney) cells. For the In vitro test, MDBK cells in ${\alpha}$-MEM(Minimum Essential Medium) were divided into 4 treatment groups according to drug types and dosages as follows; the control(group A), group B was treated with 0.3mM caffeine, group C was treated with 0.3mM caffeine and 0.3mM ferric chloride, group D was treated with 0.3mM caffeine and 0.3mM vitamin E. Those groups were further divided into 5 subgroups according to the time lapsed(control, 4hrs, 8hrs, 24hrs and 48hrs lapsed group). The concentrations of the carbonyl group and malondialdehyde(MDA) and the patterns of the SDS-PAGE(Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis) and fatty acid compositions were analyzed to determine the oxidative damages and metabolic changes on the lipid and protein components in the MDBK cells. The results obtained from this study were summarized as follows; 1. The concentrations of carbonyl group and malondialdehyde in MDBK cells of group C were significantly higher(p<0.01) in comparison to the control, and increased according to the time lapsed. But the results of groups B and D were little different in comparison to the group C. 2. As the analytical results of fatty acid compositions in MDBK cells, the proportions of palmitoleic acid and linoleic acid in groups B, C and D were lower in comparison to the control, while the proportion of arachidonic acid in groups B, C and D were significantly higher(p<0.01) in comparison to the control. 3. In order to determine the oxidative damages to the protein in MDBK cells, the patterns of the SDS-PAGE were examined and the patterns of SDS-PAGE in groups C and D were significantly different between 43kd and 200kd of molecular weight.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.204-204
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• 2018

수문 기상레이더는 강우량을 바로 추정하지 못하고 여러 단계의 정량적 강우량 추정과정을 거치게 되므로 많은 불확실성 발생요소가 존재한다. 불확실성 관련한 기존 연구들은 정량적 레이더 기반 강우량 추정과정에서 보정방법을 이용하여 각 단계별 불확실성을 줄이는 연구들을 수행하였다. 하지만 기존 연구들은 전체 과정에 대한 포괄적인 불확실성을 나타내지 못하고 각 단계별 불확실성의 상대적인 비율도 제시하지 못하는 단점이 있다. 본 연구에서는 정량적 레이더강우량 추정과정의 각 단계별 불확실성을 정량화하고 불확실성 전파를 나타낼 수 있는 적합한 방법을 제시하였다. 첫 번째로 초기와 최종 불확실성, 각 단계별 불확실성의 변동과 상대적인 비율을 나타낼 수 있는 새로운 개념을 제안하였다. 두 번째로 레이더기반 추정과정의 불확실성 정량화와 전파과정을 분석하기 위해 Maximum Entropy Method (MEM), Uncertainty Delta Method (UMD), Modified-Narrow Uncertainty Method (M-NUM)를 적용하였다. 세 번째로 레이더기반 강우량 추정과정의 불확실성 정량화를 위해 2개 품질관리 알고리즘, 2개 강우량 추정방법, 2개 후처리 강우량 보정방법을 2012년 여름철 18개 사례에 대하여 사용하였다. 적용결과, 최종 불확실성(후처리 강우량 보정 불확실성)이 초기 불확실성(품질관리 불확실성)보다 작게 나타나 불확실성이 감소하는 것으로 나타났다. 하지만 레이더강우량 추정단계의 불확실성은 증가하는 것으로 나타났다. 또한 레이더강우량 추정과정에서 각 단계별로 적합한 방법을 선정하는 것이 각 단계별로 불확실성이 감소시킬 수 있음을 확인하였다. 따라서 본 연구는 새로운 방법이 명확히 불확실성을 정량화할 수 있으며 정확한 정량적 레이더 강우추정에 기여할 것으로 판단한다.

• Korean Journal of Animal Reproduction
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• v.23 no.2
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• pp.105-111
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• 1999

The effects of exogenous spleen cells on the progesterone and insulin like-growth factor-I (IGF-I) secretions in luteal cells were studied by using in vitro luteal cell culture system in the Hanwoo luteal cells. The corpora lutea(CL) were collected and pooled from the Korean native cattle(Hanwoo) ovaries from a local slaughter house. After enzymatic dissociation, combined large and small luteal cells(LLC and SLC)(1.0$\times$10$^{6}$ cells/$m\ell$) were incubated in D-MEM media containing antibiotics and 10% FCS. Spleen cells (1.0$\times$10$^{6}$ cells/$m\ell$) obtained from castrated adult male Hanwoo were added to luteal cells and co-cultured for 24 h in the absence or presence of luteinizing hormone (LH) (100 ng). Progesterone contents from luteal tissues were increased at CL-3 stage during each stage of estrous cycle. Progesterone secretion from luteal cell culture by the presence of LH (100 ng/$m\ell$) was positively stimulated compared with control. However, progesterone secretion was not changed by the addition of 5, 10 and 20% of spleen cells in the absence of LH. Co-culture of luteal cells with 10% of spleen cells in the presence of LH(l00ng/$m\ell$) significantly. enhanced after 24 h of culture. IGF-Isecretion from in vitro luteal cells co-culture by the addition of spleen cells (5%, 10% and 20%) was not significantly effected. Besides, in the presence of LH (100ng/$m\ell$), IGF-Isecretions from luteal cells by addition of spleen cells were higher than control media. However, LH alone significantly increased IGF-I secretion at 24 h of culture. These data provide the demonstrate that spleen cells can enhance LH action so as to stimulate progesterone secretion from Hanwoo luteal cells but have no effect to stimulate IGF-I secretion.

• Clinical and Experimental Reproductive Medicine
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• v.28 no.2
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• pp.95-103
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• 2001

연구목적: 본 연구는 생쥐 preantral follicles의 체외 배양 조건을 확립하고 이를 기초로 높은 체외 발달률 그리고 산자 생산률을 얻고자 하였다. 연구재료 및 방법 : Preantral follicles의 oocyte-granulosa cell complexes (OGCs)는 생후 12일된 FI ($C57BL{\times}CBA$)으로부터 난소를 적출하여 효소를 이용한 방법을 통해 획득하였다. 회수된 complexes는 10일 또는 12일 동안 체외 성장을 위해 Transwell-COL membrane insert로 옮겨졌고 5% FBS, 100 mIU/ml FSH, 100 mIU/ml hMC가 첨가된 ${\alpha}MEM$에서 배양되었다. 체외 성숙을 위해 1.5 IU/ml hCG가 첨가된 ${\alpha}MEM$에서 18 hrs 배양을 실시하였다. 그 후 M16에서 수정능력이 획득된 정자와 수정을 하여 4 hrs, 7 hts, 9 hrs 후에 10% FBS가 첨가된 modified M16 배양액에서 4일간 배양하거나 또는 bovine cumulus cell과 co-culture를 실시하였다. 그리고 형태적으로 정상적인 22개의 상실배와 포배를 2마리의 위임신 대리모 (ICR)의 자궁에 이식하여 산자 생산을 유도하였다. 결과: 1) OGCs 크기가 mouse preantral follicles의 핵 및 세포질 성숙에 미치는 영향을 조사하였을 때 $120{\sim}150{\mu}m$의 preantral follicles (MII: 33.0%, 난할률: 36.7%, 상실배 이상; 20.9%)은 핵 및 세포질 성숙에 있어서 $70{\sim}110{\mu}m$ (MII: 12.2%, 난할률: 10.2%, 상실배 이상: 4.8%)보다 더 높았다(p<0.001). 2)체외 성장기간의 연장이 mouse preantral follicles의 핵 및 세포질 성숙에 미치는 영향을 조사하였을 때 10일 (난할률: 38.2%)은 12일 (난할률: 20.0%)보다 난할률에서만 더 높았다 (p<0.01). 3) 체외 수정 시간의 연장이 mouse preantral follicle의 세포질 성숙에 미치는 영향을 조사하였을 때 9 hrs (난할룰 31.5%, 상실배 이상: 14.3%)은 4 hrs (난할률: 17.5%, 상실배 이상: 4.8%), 7 hrs (난할률: 20.4%, 상실배 이상: 6.1%) 보다 세포질성숙에 있어서 유의하게 높은 발달률을 나타냈다 (p<0.01). 4) 공배양이 mouse preantral follicle의 세포질성숙에 미치는 영향을 조사하였을 때 공배양 (상실배 이상: 17.4%)을 실시했을 때와 M16 (상실배 이상17.4%)에서 배양되었을 때는 차이가 없었다. 5)preantral follicle의 크기 ($120{\sim}150{\mu}m$), 체외 성장기간 (10일), 체외 수정 기간 (9시간), 배양 환경 (단지 medium만 존재)의 적절한 결과들을 종합하여 수행하였을 때 MII 성숙률, 난할률, 상실배 이상의 발달률은 30.2%, 39.3%, 22.5%이었고 총 22개의 상실배 및 포배를 2마리의 대리모에 이식했을 때 1마리가 임신했고 1마리의 산자를 생산했다. 결론: 따라서, 본 실험은 preantral follicle을 이용한 체외 배양 시스템이 생쥐 oocyte를 공급하는 또 다른 방법으로 효과적으로 이용될 수 있다는 것을 시사한다.