• Molecules and Cells
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• v.27 no.6
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• pp.635-640
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• 2009

Testis-derived germline stem (GS) cells can undergo reprogramming to acquire multipotency when cultured under appropriate culture conditions. These multipotent GS (mGS) cells have been known to differ from GS cells in their DNA methylation pattern. In this study, we examined the DNA methylation status of the H19 imprinting control region (ICR) in multipotent adult germline stem (maGS) cells to elucidate how epigenetic imprints are altered by culture conditions. DNA methylation was analyzed by bisulfite sequencing PCR of established maGS cells cultured in the presence of glial cell line-derived neurotrophic factor (GDNF) alone or both GDNF and leukemia inhibitory factor (LIF). The results showed that the H19 ICR in maGS cells of both groups was hypermethylated and had an androgenetic pattern similar to that of GS cells. In line with these data, the relative abundance of the Igf2 mRNA transcript was two-fold higher and that of H19 was three fold lower than in control embryonic stem cells. The androgenetic DNA methylation pattern of the H19 ICR was maintained even after 54 passages. Furthermore, differentiating maGS cells from retinoic acid-treated embryoid bodies maintained the androgenetic imprinting pattern of the H19 ICR. Taken together these data suggest that our maGS cells are epigenetically stable for the H19 gene during in vitro modifications. Further studies on the epigenetic regulation and chromatin structure of maGS cells are therefore necessary before their full potential can be utilized in regenerative medicine.

• Composites Research
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• v.34 no.3
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• pp.148-154
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• 2021

Carbon/epoxy composite bipolar plate (BP) is a BP that is likely to replace existing graphite bipolar plate of vanadium redox flow cell (VRFB) due to its high mechanical properties and productivity. Multi-functional carbon/epoxy composite BP requires graphite coating or additional surface treatment to reduce interfacial contact resistance (ICR). However, the expanded graphite coating has the disadvantage of having low durability under VRFB operating conditions, and the surface treatments incur additional costs. In this work, an excessive resin absorption method is developed, which uniformly removes the resin rich area on the surface of the BP to expose carbon fibers by applying polyester fabric. This method not only reduces ICR by exposing carbon fibers to BP surfaces, but also forms a unique ditch pattern that can effectively hold carbon felt electrodes in place. The acidic environmental durability, mechanical properties, and gas permeability of the developed carbon/epoxy composite BP are experimentally verified.

• Korean Journal of Veterinary Research
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• v.31 no.2
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• pp.229-234
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• 1991

Thc chimeric morulae were produced following aggregation of the half embryos which were microsurgically bisected at 8-cell and early morula stage. Different phenotypic embryos were obtained by mating ICR female mice with ICR or CBA male mice. The early morula stage was thc desirable stage for the aggregation of mouse embryos after bisection. The post-thawed survival rates of bisected-aggregated embryos that developed into normal blastocyst after conventional freezing in DMSO and ethylene glycol were 30.5 and 32.896, respectively. One offspring was produced by transferring the 67 frozen-thawed bisected-aggregated embryos.

• Corrosion Science and Technology
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• v.15 no.2
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• pp.92-107
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• 2016

Graphene was coated on austenitic and martensitic stainless steels to simulate the metallic bipolar plate of proton exchange membrane fuel cell (PEMFC). Graphene oxide (GO) was synthesized and was reduced to reduced graphene oxide (rGO) via a hydrazine process. rGO was confirmed by FE-SEM, Raman spectroscopy and XPS. Interfacial contact resistance (ICR) between the bipolar plate and the gas diffusion layer (GDL) was measured to confirm the electrical conductivity. Both ICR and corrosion current density decreased on graphene coated stainless steels. Corrosion resistance was also improved with immersion time in cathodic environments and satisfied the criteria of the Department of Energy (DOE), USA. The total concentrations of metal ions dissolved from graphene coated stainless steels were reduced. Furthermore hydrophobicity was improved by increasing the contact angle.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1177-1182
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• 2012

The corrosion resistance of 316L stainless steel coated with NiO-YSZ (Ni added yttria stabilized zirconia) was examined in a proton exchange membrane fuel cell (PEMFC) environment. The NiO-YSZ coating was carried out using a sol-gel dip coating method, and the corrosion resistance and interfacial contact resistance (ICR) were determined by the composition and morphology of the NiO-YSZ film. The corrosion resistance increased with increasing Ni content in the NiO-YSZ film, but rapid corrosion was observed when the YSZ film contained more than 15 wt % Ni due to surface cracks. The polarization resistance was improved by several orders of magnitude when 316L stainless steel was coated with a 15 wt % NiO-YSZ film compared to bare 316L. The ICR of the NiO-YSZ film was decreased to that of bare 316L when the YSZ film contained 25 wt % NiO, suggesting the possible application of NiO-YSZ coated stainless steel for a bipolar plate.

• Journal of Sasang Constitutional Medicine
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• v.4 no.1
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• pp.221-230
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• 1992

In order to investigate the effects of shipjuntaepotang (少陰人 十全大補湯) on immune response, the author performed this experimental study. Delayed type hypersensitivity (DTH) and rosette forming cells (RFC) for cell-mediated immune response, hemagglutinin (HA) titers, hemolysin (HL) titers, and carbon clearance for phagocytic function of MPS (mononuclear phagocyte system) were measured in ICR mice. The results were summarized as follows. 1. DTH in the experimental group was increased, as compared with the control group, with statistical significance. 2. RFC in the experimental group was increased, as compared with the control group, with statistical significance. 3. HA-titers were increased in the experimental group, as compared with the control group, with statistical significance. 4. HL-titers were increased in the experimental group, as compared with the control group, with statistical significance. 5. Carbon clearance was increased in the experimental group, as compared with the control group, with statistical significance. Through invivo experimental study in ICR mice, these findings suggest that shipjuntaepo-tang enhance both cellmediated and humoral immune responce.

• Journal of the Korean institute of surface engineering
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• v.48 no.3
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• pp.87-92
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• 2015

Carbon thin films were deposited on STS 316L sheets by inductively coupled plasma enhanced magnetron sputtering with or without substrate bias voltage. Typical Raman spectrum for amorphous diamond-like carbon (DLC) was obtained, and the interfacial contact resistance (ICR) was measured to show its conductive nature. The electrochemical impedance spectroscopy (EIS) was used to investigate the corrosion mechanism of the carbon coating under the polymer electrolyte membrane fuel cell (PEMFC) condition. According to the pore-corrosion mechanism, the electrolyte penetrates the carbon coating through the pores and reacts with the substrate. As the substrate corrosion proceeds, the pore enlargement occurs and the surface area of the substrate exposed to the electrolyte. Applicability of the carbon coating for the PEMFC bipolar plate was evaluated by potentiodynamic polarization experiments. Finally, an adhesion problem was briefly considered.

• Bulletin of the Korean Chemical Society
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• v.20 no.10
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• pp.1181-1185
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• 1999

The reaction of FeC5H5+ ion with ferrocene molecule is investigated using FT-ICR mass spectrometry. FeC5H5+ ions are generated by dissociative ionization of ferrocenes using an electron beam. The reaction gives rise to the formation of the adduct ion, Fe2(C5H5)3+, in competition with charge transfer reaction leading to the formation of ferrocene molecular ion, Fe(C5H5)2+·. The branching ratio of the adduct ion increases as the internal energy of the reactant ion decreases and correspondingly the branching ratio for the charge transfer reaction product decreases. The observed rate of the addition reaction channel is slower than that of the charge transfer reaction. The observation of the stable adduct ions in the low-pressure ICR cell is attributed to the radiative cooling of the activated ion-molecule complex. The mechanism of the reaction is presented to account for the observed experimental results.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.125.1-125.1
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• 2003

Effects of Compound-A, a phenylpropanoid isolated from Arctium lappa fruit, on sheep red blood cells (sRBC)-induced arthus reaction (AR) were studied in ICR male mice and determined the plaque forming cells (PFC) numbers and hemagglutinin (HA) titer. Two weeks after sensitization of i.p. injection of sRBC (4x10$^{8}$ cells), ICR male mice were challenged by i.p. injection of sRBC (2$\times{10}^8$ cells). Five days after the challenge of antigen, paw edema induced three hours after the last challenge by Arthus reaction. (omitted)

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.1
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• pp.137-147
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• 2004

In order to evaluate the antitumor activity and immunomodulatory effects of Seoleosojong-tang(SST), studies were done. We measured the cytotoxic activity for various kinds of cancer cells, inhibitory effect on activity of DNA topoisomerase I, cell adhesion to complex extracellular matrix, survival time in ICR bearing S-180, pulmonary colonization and histological changes of lung in C57BL/6 injected i.v. with B16-F10, CAM assay, expression of CD4/sup +/, CD8/sup +/, B220/sup +/, cytokine gene in spleen cell. The results were obtained as follows: 1. In cytotoxicity against A549, HT1080, 816-F10, NCL-H661 was showed cytotoxicity as compared with control. 2. The inhibitory effect on adhesion of A549, 816-F10 to complex extracellular matrix was over 40% at 100 ㎍/㎖ of SST. 3. In DNA topoisomerase I assay, SST has inhibitory effect. 4. The T/C% was 120.8 in SST treated group in S-180 bearing ICR mice. 5. In pulmonary colonization assay, a number of colonies were decreased significantly and histological changes were showed that infiltration area of cancer cells were inhibited effectively in SST treated group. 6. In CAM Assay, SST has antiangiogenic effect. 7. On the expression of positive cell to CD4/sup +/, CD8/sup +/ and 8220/sup +/ in spleen cells, CD4/sup +/ cells were increased significantly in SST treated group. 8. Effect of SST on IL-1β gene expression in splenic cell was significantly increased as function of whole concentration. 9. The gene expression of IL-4, IL-6, IL-10, IL-12, IFN-γ, TNF-α were increased in SST treated group. From above results SST could be usefully applied for antitumor activity and immunomodulatory effects, but further research of SST should be required.