• The Korean Journal of Nuclear Medicine
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• v.36 no.2
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• pp.102-109
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• 2002

Purpose : In gene therapy, tumor cells expressing the herpes simplex virus thymidine kinase are sensitive to prodrugs. Potential prodrugs IVDU and IVFRU were synthesized and radiolabeled with radioiodine for noninvasive imaging of herpes simplex virus type 1 gene expression. Material and Methods : 5-(2-trimethysilyl) vinyl-2'-deoxyuridine and 5-(2-trimethylsilyl)vinyl-2'-fluoro-2'-deoxyuridine, precursors of 5-(2--iodo)viny l-2'-deoxy uridine(IVDU) and 5-(2-iodo)-2'-vinyl-2'-deoxy-2'-fluororibofuranosyl uracil(IVFRU), were synthesized from reaction of trans-1-trimethylsillyl-2-tri-n-butylstannylethylene with 5-iodo-2'-deoxyuridine and 5-iodo-2'-fluoro-2'-deoxyuridine, respectively, on the condition of Pd catalyst. These precursors were separated from reaction mixture by silica gel column chromatography method. Each precursor was radioiodinated with radioiodine by mixing with ICI oxidizing agent. These radioiodinated compounds were purified with HPLC. Radiohalogen exchange has been shown to be effective for the synthesis of products with lower specific activity. Similarly, carrier-added and high specific activity products have been isolated in respectable radiochemical yields using ICI method. Results : Synthetic yield of precursors, IVDU and IVFRU were 43% and 18%, respectively. Radiochemical purity of both compunds was over 98%. Conclusion : We synthesized precursors of IVDU and IVFRU for monitoring of HSV1-tk gene expression. Radiotracers were radioiodinated with high radiolabeling yield by ICI method.

• Microbiology and Biotechnology Letters
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• v.10 no.3
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• pp.217-222
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• 1982

A lactic starter organism, Lactobaciilus casei YIT 9018 was treated with N-methyl-N'-nitro-N-nitrosoguanidine (NTG) to obtain phage-resistant mutants. Freshly grown cells suspended in citrate buffer were exposed to NTG of 50 g/$m\ell$ for 40 min. Among 88 colonies isolated eight colonies showed distinct resistance to phages isolated previously from milk plants. The eight new colonies showed character similar to the original L. casei except that they responded differently to phage of different sources and thus were designated as eight different mutants of L casei. From the phage resisting toaether with the fermentative ability equivalent to the mother organism the mutants may be considered to be used as starter cultures for fermented milk.

• Journal of the Korean Chemical Society
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• v.37 no.3
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• pp.327-333
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• 1993

A method was developed for the determination of trace elements in seawater by precipitate flotation preconcentration and subsequent flame atomic absorption detection. In order to quantitatively coprecipitate trace ions such as Cd(II), CuI(II), Fe(III), Mn(II), Pb(II) and Pd(II), 2.0 ml of 1.0M cerium(III) solution was added to 1.0l of seawater and the pH was adjusted to 9.5 with 5.0 M sodium hydroxide solution while stirring with a magnetic stirrer. The precipitate was floated with the aid of surfactant solution (1.0 ml of 0.3% sodium oleate) by bubbling nitrogen gas through a porous (No. 4) fritted glass disk. The floats was collected in a small Erlenmeyer flask by suction. The washed precipitate was dissolved in 8.0 M nitric acid and marked with deionized water in the volumetric flask of 10.0 ml. The analyte was determined by measuring the atomic absorbances in 100-fold concentrated solution. Above all analytes in Kangnung (East Sea) and Kanghwado (West Sea) sea waters were found to be under the detection limit of this method. The recoveries of over 92% for all analytes spiked into seawater samples showed that this method was applicable to the analysis of real seawater.

• Journal of Korean Society of Forest Science
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• v.109 no.1
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• pp.31-40
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• 2020

This study aimed to investigate the effects of climate change on the survival and growth performance of Pinus densiflora and Larix kaempferi seedlings using open-field experimental warming and precipitation manipulation. We measured the survival rate, root-collar diameter, and height, and then calculated the seedling quality index (SQI) of 2-year-old seedlings under 6 treatments [2 temperatures (TC: Control; TW: Warming) × 3 precipitation manipulations (PC: Control; PD: Decreased; PI: Increased)] and performed a two-way ANOVA to test for differences.The air temperature of the warming plots was 3℃ higher than that of the control plots, while the precipitation manipulation plots received ±40% of the precipitation received by the control plots. Temperature and precipitation treatments did not significantly affect the survival rate of P. densiflora; however, the SQI of P. densiflora decreased with increasing precipitation. In contrast, the mortality rate of L. kaempferi increased with increasing temperature and decreasing precipitation. Furthermore, in L. kaempferi, TC × PI treatment resulted in the lowest SQI with a significant interaction effect observed between the two factors. In summary, low seedling production and quality should be expected in P. densiflora as precipitation increases and in L. kaempferi as temperature increases or precipitation decreases. These results indicate species-specific sensitivities to climate change of two plant species at the nursery stage. With the occurrence of global warming, the frequencies of drought and heavy rainfall events are increased, and this could affect the survival and seedling quality of tree species. Therefore, it is necessary to improve nursery techniques by establishing new adaptation strategies based on species-specific growth performance responses.

• Molecules and Cells
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• v.46 no.3
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• pp.142-152
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• 2023

Nuclear factor erythroid 2-related factor 2 (Nrf2) mediates the cellular antioxidant response, allowing adaptation and survival under conditions of oxidative, electrophilic and inflammatory stress, and has a role in metabolism, inflammation and immunity. Activation of Nrf2 provides broad and long-lasting cytoprotection, and is often hijacked by cancer cells, allowing their survival under unfavorable conditions. Moreover, Nrf2 activation in established human tumors is associated with resistance to chemo-, radio-, and immunotherapies. In addition to cancer cells, Nrf2 activation can also occur in tumor-associated macrophages (TAMs) and facilitate an anti-inflammatory, immunosuppressive tumor immune microenvironment (TIME). Several cancer cell-derived metabolites, such as itaconate, L-kynurenine, lactic acid and hyaluronic acid, play an important role in modulating the TIME and tumor-TAMs crosstalk, and have been shown to activate Nrf2. The effects of Nrf2 in TIME are context-depended, and involve multiple mechanisms, including suppression of proinflammatory cytokines, increased expression of programmed cell death ligand 1 (PD-L1), macrophage colony-stimulating factor (M-CSF) and kynureninase, accelerated catabolism of cytotoxic labile heme, and facilitating the metabolic adaptation of TAMs. This understanding presents both challenges and opportunities for strategic targeting of Nrf2 in cancer.

• Journal of the Korean Chemical Society
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• v.34 no.2
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• pp.179-183
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• 1990

New synthesis and electroanthennogram (EAG) responses of the pheromones of the diamond back moth Plutella xylostella L. are described. Lithium dianion of propargyl alcohol was alkylated with 1-bromononane to give 2-dodecyn-1-ol, which was converted to 11-dodecyn-1-ol by acetylene-zipper reaction. Dianion of 11-dodecyn-1-ol was alkylated with 1-bromobutane to provide 11-hexadecyn-1-ol, which was in turn reduced over Pd/BaSO4 to afford (Z)-11-hexadecen-1-ol (3). (Z)-11-Hexadecen-1-ol was oxidized and acetylated to (Z)-11-hexadecen-1-al (1) and (Z)-11-hexadecen-1-yl acetate (2), respectively. The electroantennogram (EAG) responses of the diamond back moth to the pheromone compouds thus synthesized were measured.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.1079-1085
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• 2008

The chemopreventive activity of sulforaphane (SFN) occurs through its inhibition of carcinogen-activating enzymes and its induction of detoxification enzymes. However, the exact mechanisms by which SFN exerts its anti-carcinogenic effects are not fully understood. Therefore, the mechanisms underlying the cytoprotective effects of SFN were examined in MCF-7 breast cancer cells. Exposure of cells to SFN (10 ${\mu}M$) induced a transcriptional change in the AKR1C3 gene, which is one of aldo-keto reductases (AKRs) family that is associated with detoxification and antioxidant response. Further analysis revealed that SFN elicited a dose- and time-dependent increase in the expression of both the NRF2 and AKR1C3 proteins. Moreover, this up-regulation of AKR1C3 was inhibited by pretreatment with antioxidant, N-acetyl-L-cysteine (NAC), which suggests that the up-regulation of AKR1C3 expression induced by SFN involves reactive oxygen species (ROS) signaling. Furthermore, pretreatment of cells with LY294002, a pharmacologic inhibitor of phosphatidylinositol 3-kinase (PI3K), suppressed the SFN-augmented Nrf2 activation and AKR1C3 expression; however, inhibition of PKC or MEK1/2 signaling with $G\ddot{o}6976$ or PD98059, respectively, did not alter SFN-induced AKR1C3 expression. Collectively, these data suggest that SFN can modulate the expression of the AKR1C3 in MCF-7 cells by activation of PI3K via the generation of ROS.

• Korean Journal of Applied Biomechanics
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• v.16 no.4
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• pp.135-145
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• 2006

The aim of this study was to find out the differences of biomechanical factors from touching down the vaulting board to landing when techniques of 1/1Turn, stretched, and Tucked were performed on the old vaulting horse and on the new vaulting table. Three national representative men gymnasts were sampled for this study. Three dimension motion analyses by means of six Sony PD-150 video cameras with the velocity of 60 fps were used. As a result of analyzing the kinetic data from two kind of vaulting table, the following conclusions were made. 1. There was not significant differences of angular momentum between the old and the new vaulting table in all three techniques except the phase of stepping on the vaulting board and contacting the vaulting horse in the Tucked technique. IN the two phases above, the angular momentum in the new vaulting table was greater than that of the old vaulting horse. 2. There were few significant differences between the old and the new vaulting horses in the horizontal and vertical reaction force according to techniques when stepping was performed. However, it appeared tendency that the horizontal and vertical reaction force in the new vaulting table was a little greater than that of the old vaulting horse when the 1/1Turn, the Stretched and the Tucked were performed.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.771-774
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• 2003

Passivation Ledge's device is taken possession on one-side to the Emitter in this Paper. contact used in this paper Pt as Passivation Ledge of device to use Schottky Diode which has leitmotif, It is accomplished Current Modulation that we wish to do purpose using this device. Space Charge acts as single device which is becoming Passivation to know this phenomenon. This device becomes floating as well as Punched-through. V$_{L}$ (Voltage for Ledge) = - 0.5V ~ 0.5V variable values , PD(Partially Depleted ; Λ＞0), as seeing FD(Fully Depleted ; A = 0) maximum electric current gains and Gummel Plot of I-V characteristics (V$_{L}$ = 0.1/ V$_{L}$ = -0.1 ). Becomming Degradation under more than V$_{L}$ = 0.1 , less than V$_{L}$ =-0.05 and Maximum Gain(=98.617076 A/A) value in the condition V$_{L}$ = 0.1. A Change of Modulation is electric current gains by using Schottky Diode and Extrinsic Base PN Diode of Passivation Ledge to Emitter Depletion Layer in HBT of Gummel-Poon I-V characteristics and the RF wide-band electric current gains change the Modulation of CE(Common-Emitter) amplifier description, and it had accomplished Current Gain Modulation by Ledge Bias that change in high frequency and wide bands. wide bands.s.

• BMB Reports
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• v.45 no.5
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• pp.287-292
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• 2012

FGF-2 is involved in cell survival, proliferation, apoptosis, and angiogenesis in a wide variety of cells. FRGRs, PI3K and MAP kinases are well known mediators of FGF signaling. Despite its known roles during many developmental processes, including osteogenesis, there are few known targets of FGF-2. In the present study, we identified Bcl2-A1 and Bcl-xL as two prominent targets involved in promoting cell survival. Pretreatment of ATDC5 cells with FGF-2 increased cell survival, while siRNAs specific for Bcl2-A1 and Bcl-xL compromised the anti-apoptotic effect of FGF-2, sensitized the cells to apoptosis triggered by TNF-${\alpha}$. Chemical inhibition of FGFR, NFkB, and PI3K activity by PD173074, pyrrolidine dithiocarbamate, and LY294002 respectively abrogated the FGF-2-mediated induction of Bcl2-A1 and Bcl-xL expression. Taken together, our data demonstrate that a subset of Bcl2 family proteins are the targets of FGF-2 signaling that promotes the survival of ATDC5 cells.