• Korean Journal of Environmental Agriculture
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• v.7 no.2
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• pp.96-101
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• 1988

It is important to assess the effects of ionic strength and type of anions when studying the adsorption of heavy metals on zeolite because the background salt may complex with heavy metals and compete for adsorption sites. This experiment was carried out to determine the effect of ionic strength and anion species($Cl^-$, $SO^{2-}\;_4$, and $ClO^-\;_4$) on heavy metal adsorption. Heavy metal adsorption by zeolite from solutions in the range of 10 to 50ppm was studied in the presence of NaCl, $Na_2SO_4$ and $NaClO_4$, with different concentrations. The ionic strength ranged from 0.01 to 1.00. Adsorption of heavy metal cations could be described by the Freundlich isotherm equation. Increasing the ionic strength of equilibrium solutions, the amounts of heavy metal adsorbed on the zeolite surfaces decreased in all three of the anion systems. This fact could be attributed to the competition of background salt cation and the decrease in initial activity of heavy metal cations. In the presence of Cl anion, less adsorption resulted than in the presence of $SO_4$ or $ClO_4$ anions of the same ionic strength, indicating the presence of uncharged and negatively charged complexes of heavy metal with Cl ligands.

• Journal of Korean Neurosurgical Society
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• v.29 no.4
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• pp.477-484
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• 2000

Objective : Despite advances in the understanding of tumor biology and the tumor immunology, there has been no effective treatment. The Intercellular adhesion molecule-1(ICAM-1) has been shown to be important in interaction involving cells of the immune system and to be upregulated in a number of cell culture systems by cytokines, including immune interferon($IFN-{\gamma}$) and tumor necrosis $factor-{\alpha}$($TNF-{\alpha}$). ICAM-1 has been identified as one of the ligands for lymphocyte function-associated antigen-1(LFA-1). The effectiveness of various cytokines to ICAM-1 induction on cultured human glioblastoma cell lines and potential efficacy of immunotherapy were studied. Method : Human glioblastoma cell lines, U-251 MG, U-373 MG were trypsinized and suspended at $1{\times}10^5cells/ml$ and grown on 8 well chamber slide, the cells were incubated in 0.3ml medium alone or medium containing $IFN-{\gamma}$(1000U/ml) or $TNF-{\alpha}$(250U/ml) or $IFN-{\gamma}$ plus $TNF-{\alpha}$ for 6, 12, 24, 48 and 72 hours. The coverslip were then removed and stained with a 1/30 dilution of anti-ICAM-1 antibody. Result : Surface antigen expression of ICAM-1 was increased by incubating glioblastoma cell lines with $IFN-{\gamma}$ and $TNF-{\alpha}$. Combined effect of $IFN-{\gamma}$ and $TNF-{\alpha}$ has induced more ICAM-1 expression on glioblastoma cell lines. Upregulation of ICAM-1 expression in an established glioblastoma cell line was of greater magnitude and more rapid following incubation with $IFN-{\gamma}$ plus $TNF-{\alpha}$. Surface antigen expression of ICAM-1 was increased for up to 48 hours after cytokine treatment on both cell lines(p<0.05). There was no difference on both cell lines(p>0.05). Conclusion : The results of the present study indicate that ICAM-1 expression in glioblastoma cell lines, U-251 MG and U-373 MG, are induced and enhanced after treatment with $IFN-{\gamma}$ and $TNF-{\alpha}$. Combined effect of $IFN-{\alpha}$ and $TNF-{\gamma}$ is stronger and more rapid than $IFN-{\gamma}$ or $TNF-{\alpha}$ alone.

• Journal of the Korean Chemical Society
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• v.37 no.12
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• pp.1047-1052
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• 1993

The electronic spectra of enzyme-model organocobalt(Ⅲ) complexes containing completely or partially conjugated macrocyclic ligands were measured in various solvents to investigate the solvent effect on the charge transfer band for the axial cobalt-carbon bond by the extent of conjugation in the equatorial macrocyclic ring; completely conjugated, $CH_3CoL,\;C_6H_5CoL,\;CNCoL,\;CH_3CoL',\;CNCoL'$, partially conjugated $CH_3(py)Co(DH)_2, CH_3CoL＂$, unconjugated dienes, $[CH_3Co(1,4-CT)](ClO_4)_2$, and open ring, $CH_3Co(salen)$. The position of the charge transfer band which corresponds to the cobalt-carbon bond was shifted to a shorter wavelength as the polarity of solvent increased and the transition energy $(E_T)$ had a linear relationship with solvent polarity parameter, Z-value, only in the case of completely conjugated system. However, the linear correlation between $E_T$and Z was not observed for partially conjugated and open ring systems.

• Polymer(Korea)
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• v.36 no.1
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• pp.98-103
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• 2012

Poly(2,6-dimethyl-1,4-phenylene ether) (PPE) was synthesized using $Cu(NO_2)_2{\cdot}3H_2O$ or CuCl catalyst with various amounts of ligand and base in several different solvent systems. CuCl/1-methylimidazole/ammonium hydroxide was found to be an effective catalyst system which showed the highest polymer yield and molecular weight. The effects of catalyst/monomer ratio, different amine ligands, and the content of mono-functional reagent 2,4,6-trimethylphenol (TMP) additive on the polymer yield and molecular weight were investigated. Among the co-solvent systems used in this polymerization, chloroform/methanol 9/1(v/v) gave the highest polymer yield and molecular weight ($\overline{M_n}$ 55 K, $\overline{M_w}$ 92 K, PDI 1.7). The catalytic activity between CuCl and CuI was compared by oxygen-uptake experiments and the formation of sideproduct, 5,5'-tetramethyl-4,4'-diphenoquinone (DPQ), was analyzed by ultraviolet spectroscopy.

• Journal of Radiation Industry
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• v.10 no.4
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• pp.189-192
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• 2016

$^{68}Ga$ has emerged as a promising candidate for non-invasive diagnostic imaging within Positron Emission Tomography (PET) because of its advantageous radiochemical characteristics ($t_{1/2}=68min$, ${\beta}^+$ yield ~89%). $^{68}Ga$ forms a stable chelation with various ligands and it is possible to be quickly and easily study using a $^{68}Ge/^{68}Ga$ generator. Commercial $^{68}Ge/^{68}Ga$ generators are chromatographic system using the inorganic materials such as alumina and tin dioxide which are employed as column matrixes for $^{68}Ge$. In this study, we tried out to make $^{68}Ge/^{68}Ga$ generator system with the $^{68}GeO_2$ microstructures for column matrix. $^{68}Ge$ tends to have stable bond with oxide as $^{68}GeO_2$ microstructures. The $^{68}GeO_2$ has been synthesized by hydrolysis of $GeCl_4$ (sol-gel method) and characterized by X-ray diffraction and scanning electron microscope for geometrical analysis. The stability of $GeO_2$ was tested using eluents with diverse solvents(water, ethanol and 0.1 N HCl). The radioactivity of $^{68}Ga^{3+}$ in eluate through $GeO_2$ was measured to prove a function as column material for a generator.

• Journal of Life Science
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• v.31 no.10
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• pp.954-959
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• 2021

Apoptosis is an important mechanism that regulates cellular populations to maintain homeostasis, and the caspases, a family of cysteine proteases, are key mediators of the apoptosis pathway. Caspase-8 is an initiator caspase of the extrinsic apoptotic pathway, which is initiated by extracellular stimuli. Caspase-8 have two conserved domains, N-terminal tandem death effector domains (DED) and C-terminal two catalytic domain, which are important for this extrinsic apoptosis pathway. In extrinsic apoptosis pathway, death receptors which members of TNF superfamily are activated by binding of death receptor specific ligands from cell outside. After the activated death receptors recruit adaptor protein Fas-associated death domain protein (FADD), death domains (DD) of death receptor and FADD bind to each other and FADD combined with death receptor recruits procaspase-8, a precursor form of caspase-8. The DED of FADD and procaspase-8 bind to one another and FADD-bound procaspase-8 is activated by cleavage of the prodomain. This death receptor-FADD-caspase-8 complex called death inducing signaling complex (DISC). Cellular FLICE-inhibitory proteins (c-FLIPs) regulate caspase-8 activation by acting both anti- and pro-apoptotically, and caspase-8 activation initiates the activation of executioner caspases such as caspase-3. Finally activated executioner caspases complete the apoptosis by acting critically DNA degradation, nuclear condensation, plasma membrane blebbing, and the proteolysis of certain caspase substrates.

• Journal of Breast Cancer
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• v.21 no.4
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• pp.371-381
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• 2018

Purpose: Immune suppression is common in patients with advanced breast cancer but the mechanisms underlying this phenomenon have not been sufficiently studied. In this study, we aimed to identify B7 family members that were able to predict the immune status of patients, and which may serve as potential targets for the treatment of breast cancer. We also aimed to identify microRNAs that may regulate the expression of B7 family members. Methods: The Cancer Genome Atlas data from 1,092 patients with breast cancer, including gene expression, microRNA expression and survival data, were used for statistical and survival analyses. Polymerase chain reaction and Western blot were used to measure messenger RNA and protein expression, respectively. Luciferase assay was used to investigate direct microRNA target. Results: Bioinformatic analysis predicted that microRNA (miR)-93, miR-195, miR-497, and miR-340 are potential regulators of the immune evasion of breast cancer cells, and that they exert this function by targeting CD274, PDCD1LG2, and NCR3LG1. We chose CD274 for further investigations. We found that miR-195, miR-497, and CD274 expression levels were inversely correlated in MDA-MB-231 cells, and miR-195 and miR-497 expressions mimic inhibited CD274 expression in vitro. Mechanistic investigations demonstrated that miR-195 and miR-497 directly target CD274 3' untranslated region. Conclusion: Our data indicated that the level of B7 family members can predict the prognosis of breast cancer patients, and miR-195/miR-497 regulate CD274 expression in triple negative breast cancer. This regulation may further influence tumor progression and the immune tolerance mechanism in breast cancer and may be able to predict the effect of immunotherapy on patients.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.4 no.2
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• pp.65-72
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• 2018

Prostate specific membrane antigen (PSMA) is a cell surface membrane protein, which is overexpressed in most prostate cancer. Recently, PET imaging with $[^{68}Ga]$PSMA-HBED-CC has been widely used for the diagnosis of recurrent prostate cancer and the studies on the diagnostic potential of $^{64}Cu$-labeled PSMA ligands reported actively. In this study, we monitored with biological evaluation in vivo and PET imaging of $^{64}Cu$-labeled PSMA ligand ($[^{64}Cu]$PSMA-617). The radiolabelling efficiency and stability of $[^{64}Cu]$PSMA-617 were confirmed by radio-thin layer chromatography. The radiolabeling efficiency of $[^{64}Cu]$PSMA-617 showed over 95%, and stabilities of intact remained over 98% in both human and mouse serum for 48 h. In normal male mice, in vivo uptake of $[^{64}Cu]$PSMA-617 in several organs was measured at 2, 4, 6, 24, 48 h after injection. Rapid blood clearance was observed for $[^{64}Cu]$PSMA-617. The high uptake was observed in the lung, liver, intestines and kidneys at 2 h postinjection, but was low in the other organs (1-2 %ID/g) at 4 h. The dynamic PET/CT images of 22RV1 tumor-bearing nude mice were acquired during 60 min and additionally acquired 24 h and 48 h after injection. In dynamic PET images, $[^{64}Cu]$PSMA-617 uptake ratio in tumors versus muscle was increased as time elaplsed until 60 minutes and remained in tumors at 48 h. In these results, the PET/CT imaging using $[^{64}Cu]$PSMA-617 in prostate cancer is expected to be useful for the diagnosis and treatment of prostate cancer patients.

• Korean Journal of Poultry Science
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• v.46 no.3
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• pp.185-191
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• 2019

Nucleoporin 210 (Nup210) is associated with several physiological processes including muscle and neural cell differentiation, autoimmune diseases, and peripheral T cell homeostasis. Chicken Nup210 (chNup210) gene was originally identified as one of the differentially expressed genes (DEGs) in the kidney tissues of chicken. To elucidate the role of Nup210 in metabolic disease of chicken, we studied the molecular characteristics of chNup210 and analyzed its gene expression under the stimulation of Toll-like receptor 3 (TLR3) ligands. The Nup210 genomic DNA and amino acid sequences of various species including fowls, fishes, and mammals were retrieved from the Ensemble database and subjected to bioinformatics analyses. The expression of Nup210 from several chicken tissues was probed through qRT-PCR, and chicken fibroblast DF-1 cell line was used to determine the change in expression of chNup210 after stimulation with TLR3 ligand, polyinosinic-polycytidylic acid (poly (I:C)). The chNup210 gene was highly expressed in chicken lung and spleen tissues. Although highly conserved among the species, chNup210 was evolutionary clustered in the same clade as that of duck compared to other mammals. Furthermore, this study revealed that chNup210 is expressed in TLR3 signaling pathway and provides fundamental information on Nup210 expression in chicken. Future studies that offer insight into the involvement of chNup210 in the chicken innate immune response against viral infection are recommended.

• Bulletin of the Korean Chemical Society
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• v.9 no.6
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• pp.338-341
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• 1988

Two crystal structures of fully dehydrated silver and potassium exchanged zeolite A, stoichiometries of $Ag_{9.3}K_{{2.7}^-}A$ (${\alpha}$ = 12.282(2) ${\AA}$) and $Ag_{10.7}K_{{1.3}^-}{\AA}$ (${\alpha}$ = 12.287(2) A) per unit cell, have been determined from 3-dimensional x-ray diffraction data gathered by counter methods. All structures were solved and refined in the cubic space group Pm3m at 21(1)$^{\circ}C$ . The crystals of $Ag_{9.3}K_{{2.7}^-}A$ and $Ag_{10.7}K_{{1.3}^-}A$ were prepared by flow method using exchange solutions in which mole ratios of $AgNO_3$ and $KNO_3$ were 1:10 and 1:5, respectively, with total concentration of 0.05M. The structures of the dehydrated $Ag_{9.3}K_{{2.7}^-}A$ and $Ag_{10.7}K_{{1.3}^-}A$ were refined to yield the final error indices $R_1$ = 0.037 and $R_2$ = 0.040 with 321 reflections, and $R_1$ = 0.042 and $R_2$ = 0.043 with 371 reflections, repectively, for which I > 3${\sigma}$(I). In both structures, eight $Ag^+$ ions are found nearly at 6-ring centers and each $Ag^+$ ion is nearly in the (1 1 1) plane at its O(3) ligands. The 8-ring sites are preferentially occupied by $K^+$ ions in both structures. 1.3 and 1.7 reduced silver atoms per unit cell were found inside of sodalite units of $Ag_{9.3}K_{{2.7}^-}A$ and that of $Ag_{10.7}K_{{1.3}^-}A$, respectively. These reduced silver species were presumably formed from the reduction of $Ag^+$ ions by oxide ions of residual water molecule or of the zeolite framework. These two crystals may be presented as hexasilver cluster in 21.7% and 28.3% of sodalite unit cells for $Ag_{9.3}K_{{2.7}^-}A$ and $Ag_{10.7}K_{{1.3}^-}A$, repectively.