• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.11
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• pp.855-858
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• 2011

In this paper, in order to suppress unwanted current paths originating from adjacent cells in a passive crossbar array based on resistive random access memory (RRAM) without extrinsic switching devices, 1-diode type RRAM which consists of a 0.2% chromium-doped strontium titanate (Cr-$SrTiO_3$) film deposited on a silicon substrate, was proposed for high packing density, and intrinsic rectifying characteristics from the current versus voltage characteristics were successfully demonstrated.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.6 no.2
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• pp.116-130
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• 2020

The aging society is globally one of biggest issue because it is related with various degenerative brain disease such as dementia, Parkinson's disease, Alzheimer's disease, multiple sclerosis, and cerebrovascular disease. These diseases are characterized by misfolded-protein aggregation; another pathological trait is "neuroinflammation". In physiological state, the resting microglia cells are activated and it removes abnormal synapses and cell membrane debris to maintain the homeostasis. In pathological state, however, microglia undergo morphological change form 'resting' to 'activated amoeboid phenotype' and the microglia cells are accumulated by neuronal damage, the inflammatory reactions induced nerve metamorphosis with a variety of neurotoxic factors including cytokines, chemokines, and reactive oxygen species. Thus, the activated microglia cell with various receptors (TSPO, COX, CR, P2XR, etc.) was perceived as important biomarkers for imaging the inflammatory progression. In this review, we would like to introduce the current status of the development of radiotracers that can image activated microglia.

• Applied Chemistry for Engineering
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• v.30 no.2
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• pp.205-211
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• 2019

Over the past several decades, the polymer dispersed liquid crystal (PDLC) has received particular attention as a material for developing smart window due to their electro-optical switchable properties. In this study, PDLC cells were fabricated using acrylate monomers, namely 2-hydroxyethyl acrylate (2-HEA) and ethylene glycol phenyl ether acrylate (EGPA), and the effect of the monomer composition on their electro-optical properties was investigated. The monomer mixture with a low viscosity (~10 cps) was easily filled between indium tin oxide (ITO) glasses by capillary action at room temperature. PDLC cells prepared using the mixture ratio of 1 : 9 (2-HEA : EGPA) did not show a complete opaque state at a 0 V condition but exhibited unstable electro-optical properties under an electric field. As the LC composition increased in the reaction mixture for PDLC cell preparation, the $V_{th}$ (threshold voltage) and $V_{sat}$ (saturation voltage) values as well as contrast ratio (CR) increased. $V_{th}$ and $V_{sat}$ values also increased with the cell gap thickness. PDLC cells with a $20{\mu}m$ cell gap thickness exhibited higher CR than those with 10 and $40{\mu}m$ cell gap thicknesses. Particularly, PDLC cells prepared using the mixture ratio of 7 : 3 (2-HEA : EGPA) showed excellent electro-optical properties such as a low driving voltage and high contrast ratio.

• Natural Product Sciences
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• v.2 no.1
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• pp.29-36
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• 1996

This study was to evaluate the antitumor and immunopotentiation effects of Manda Enzyme (ME). Oral administration of ME (0.2ml/mouse) to tumor bearing mice significantly prolonged survival rate compared to the control group with the prolongation ratio of 40%. The inhibition ratios for the first and the second experiments were 51.8% and 26.4%, respectively. Only the spleen index was significantly increased in the MEF-treated group, but not in the control group. Gamma globulin level of the MEF-treated group was elevated when mice were injected with sarcoma-180 cells on the left groin. Activities of natural killer (NK) and lymphokineactivated killer (LAK) cells were observed by $^{51}Cr-release$ method. Activities of NK cell against YAC-1 cells were significantly increased in the MEF treated group. And LAK cell activities against P815 cells were also significantly increased in the experimental group. These observations, therefore, suggest that ME may have an anticancer effect and immunopotentiating effect in vivo.

• Molecules and Cells
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• v.43 no.12
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• pp.1023-1034
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• 2020

Complement fragment iC3b serves as a major opsonin for facilitating phagocytosis via its interaction with complement receptors CR3 and CR4, also known by their leukocyte integrin family names, αMβ2 and αXβ2, respectively. Although there is general agreement that iC3b binds to the αM and αX I-domains of the respective β2-integrins, much less is known regarding the regions of iC3b contributing to the αX I-domain binding. In this study, using recombinant αX I-domain, as well as recombinant fragments of iC3b as candidate binding partners, we have identified two distinct binding moieties of iC3b for the αX I-domain. They are the C3 convertase-generated N-terminal segment of the C3b α'-chain (α'NT) and the factor I cleavage-generated N-terminal segment in the CUBf region of α-chain. Additionally, we have found that the CUBf segment is a novel binding moiety of iC3b for the αM I-domain. The CUBf segment shows about a 2-fold higher binding activity than the α'NT for αX I-domain. We also have shown the involvement of crucial acidic residues on the iC3b side of the interface and basic residues on the I-domain side.

• Molecules and Cells
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• v.24 no.3
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• pp.351-357
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• 2007

Regions (about 3.7-3.8 kb) of the mitochondrial genomes (rrnL-cox1) of two tardigrades, a heterotardigrade, Batillipes pennaki, and a eutardigrade, Pseudobiotus spinifer, were sequenced and characterized. The gene order in Batillipes was $\underline{rrnL}-\underline{V}-\underline{rrnS}-\underline{Q}-\underline{I}$-M-nad2-W-$\underline{C}-\underline{Y}$-cox1, and in Pseudobiotus it was $\underline{rrnL}-\underline{V}-\underline{rrnS}-\underline{Q}$-M-nad2-W-$\underline{C}-\underline{Y}$-cox1. With the exception of the trnI gene, the two tardigrade regions have the same gene content and order. Their gene orders are strikingly similar to that of the chelicerate Limulus polyphemus (rrnL-V-rrnS-CR-I-Q-M-nad2-W-C-Y-cox1), which is considered to be ancestral for arthropods. Although the tardigrades do not have a distinct control region (CR) within this segment, the trnI gene in Pseudobiotus is located between rrnL-trnL1 and trnL2-nad1, and the trnI gene in Batillipes is located between trnQ and trnM. In addition, the 106-bp region between trnQ and trnM in Batillipes not only contains two plausible trnI genes with opposite orientations, but also exhibits some CR-like characteristics. The mitochondrial gene arrangements of 183 other protostomes were compared. 60 (52.2%) of the 115 arthropods examined have the M-nad2-W-C-Y-cox1 arrangement, and 88 (76.5%) the M-nad2-W arrangement, as found in the tardigrades. In contrast, no such arrangement was seen in the 70 non-arthropod protostomes studied. These are the first non-sequence molecular data that support the close relationship of tardigrades and arthropods.

• The Korean Journal of Nuclear Medicine
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• v.1 no.1
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• pp.21-35
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• 1967

Anemia is a usual finding in advanced malignant diseases. Various mechanisms were reported as to be involved in the development of anemia of this kind, and they may differ in individual cases. Tumor anemias may be due, for instance, to chronic blood loss, shortened life span of the red blood cells or a decreased hemopoiesis in the bone marrow. The serum iron and copper levels, total iron binding capacity, apparent half survival of $^{51}Cr$-labelled red blood cells were measured along with the ferrokinetic studies using $^{59}Fe$ in 64 patients with various malignant tumors. Following were the results: 1. The serum iron levels were decreased in all cases. There existed no correlation between the serum iron levels and the severity of the diseases. 2. The serum copper levels were increased, particularly in lung cancer, rectal cancer, hepatoma and various sarcomas. There was also no correlation between the serum copper levels and the severity of the diseases. 3. The serum iron levels appeared to be inversely proportional to the serum copper levels. 4. The total iron binding capacities were within normal limits in all cases. There were also no correlations between the total iron binding capacities, serum iron levels and the severity of the diseases. 5. The patients could be classified according to the ferrokinetic patterns, namely, that of iron deficiency anemia in 10 cases, that of refractory anemia in 6 cases, normal in 1 case and that of atypical abnormal in 9 cases. 6. Apparent half survival time of $^{51}Cr$-labelled red blood cells were definitely shortened in half of the cases.

• Korean Journal of Animal Reproduction
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• v.20 no.2
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• pp.163-170
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• 1996

The effect of several potential antioxidants and amino acids were examined as a means of increasing the development of in vitro matured and in vitro fertilized oocytes into morulae or blastocysts. Bovine embryos developed to the 2~8 cell stage after in vitro fertilization were cultured for 5 to 6 days at 39$^{\circ}C$ in CR1aa containing varing concentraton of the antioxidants and amino acid in a gas phase consisting of 5% CO2, high humidified air. At 5~6 days, embryo developments were reduced, and embryos were fixed and stained with Hochest 33342 DNA stain to facilitate counting of cells. In experiment 1, the proportion of embryos developed to morulae and blastocysts in CR1aa containing 1mM, 2.5mM taurine (22.6% and 20.4%) was slightly higher than those of 0, 5 and 10mM Taurine (5.7, 5.7 and 3.9%, P<0.05). In experiment 2, addition of glutathione did not improve blastocyst development (P>0.05). In experiment 3, concentations of superoxide dismutase(SOD) ranging from 300 to 1,000 U did not affect the propotion of embryos developing into blastocysts (P>0.05). In experiment 4, addition of 250 U catalase(38.5%) was slighty higher than those of 0, 500 and 1,000U. In experiment 5, the proportion of embryo developed beyond morula stage in CR1aa with taurine plus EDTA was slighty higher than other treatments(15.7, 26.0 and 29.2%), there were no significantly increases in cell number among treatments(P>0.05). These results are indicating that antioxidants and amino acids can increase the proportion of embryos that develop into morulae and blastocysts, but did not increas in cell number of blastocysts.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.5
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• pp.671-676
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• 2008

Forty-eight Naemi lambs (avg. BW 31.7 kg) were transported by truck for a distance of 1,450 km from Al-Jouf to Riyadh, Saudi Arabia. On arrival day, the lambs were randomly allocated to four groups receiving diets supplemented with 0.0, 0.3, 0.6 and 0.9 ppm organic chromium (Cr). Each group consisted of four separately housed replicates of three lambs each. The animals were fed ad libitum on a grower diet for 84 days. Blood samples were obtained shortly before transportation, upon arrival and at weekly intervals thereafter from all lambs for analysis of plasma and serum. Plasma glucose and serum cortisol, total protein, albumin, urea-N and total cholesterol concentrations were determined. A cursory clinical examination of the lambs, along with rectal temperature, was undertaken at different intervals during the experiment. The lambs were inoculated each with 2 ml i.v. chicken red blood cells (CRBC) on days 0, 21, and 42. Serum total, IgG and IgM antibody titers were determined at weekly intervals post-immunization. An in vivo intradermal hypersensitivity test was carried out on 6 lambs from each group on days 10 and 70. Transportation of the lambs resulted in a significant (p<0.001) elevation of serum cortisol, total protein and albumin levels, as well as increased plasma glucose concentration, with corresponding decrease in total cholesterol, while blood urea-N remained largely unchanged. These constituents returned to normal levels during subsequent weeks, with no significant differences in their concentrations being observed between the Cr-supplemented groups and controls. Rise in rectal temperature after transportation was reduced to a greater extent (p<0.05) in Cr-supplemented versus control lambs. Total, IgG and IgM antibody titers against CRBC rose significantly (p<0.05) during immunizations in all groups, with significantly and linearly higher (p<0.05) total and IgG titers in Cr-supplemented versus control lambs. By contrast, no significant effect due to Cr supplementation was recorded in IgG titers, which increased equally in Cr-fed and control groups. Skin thickness in response to intradermal inoculation of phytohaemagglutinin (PHA) was also significantly (p<0.01) increased as a result of Cr supplementation. These results indicate that dietary Cr supplementation might be useful during stress especially for enhancing immune responses in transport-stressed lambs.

• Molecules and Cells
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• v.44 no.1
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• pp.26-37
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• 2021

Human papillomaviruses (HPVs) cause cellular hyperproliferation-associated abnormalities including cervical cancer. The HPV genome encodes two major viral oncoproteins, E6 and E7, which recruit various host proteins by direct interaction for proteasomal degradation. Recently, we reported the structure of HPV18 E7 conserved region 3 (CR3) bound to the protein tyrosine phosphatase (PTP) domain of PTPN14, a well-defined tumor suppressor, and found that this intermolecular interaction plays a key role in E7-driven transformation and tumorigenesis. In this study, we carried out a molecular analysis of the interaction between CR3 of HPV18 E7 and the PTP domain of PTPN21, a PTP protein that shares high sequence homology with PTPN14 but is putatively oncogenic rather than tumor-suppressive. Through the combined use of biochemical tools, we verified that HPV18 E7 and PTPN21 form a 2:2 complex, with a dissociation constant of 5 nM and a nearly identical binding manner with the HPV18 E7 and PTPN14 complex. Nevertheless, despite the structural similarities, the biological consequences of the E7 interaction were found to differ between the two PTP proteins. Unlike PTPN14, PTPN21 did not appear to be subjected to proteasomal degradation in HPV18-positive HeLa cervical cancer cells. Moreover, knockdown of PTPN21 led to retardation of the migration/invasion of HeLa cells and HPV18 E7-expressing HaCaT keratinocytes, which reflects its protumor activity. In conclusion, the associations of the viral oncoprotein E7 with PTPN14 and PTPN21 are similar at the molecular level but play different physiological roles.