• Journal of Korea Technology Innovation Society
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• v.15 no.3
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• pp.481-499
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• 2012

This paper shows a empirical results by adopting Kauffman' NK model. First, we find interdependence parameter K is nine in the technological ecosystem Landscape. According to principal component analysis, our technological ecosystem landscape is based on K=N-1 technology structure. Second, to Kauffman NK model, our technological ecosystem landscape is completely uncorrelated each other and contains a large number of local optima. As additional technology rises, the number of local optima rises rapidly. Our results mean that the more complexity in the technological ecosystem landscape, the less effective technology innovation will be in our country's technology system.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.4039-4044
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• 2014

Background: The aim of this study was to investigate the anti-cancer effects and mechanisms of immunochemotherapy of 5-fluorouracil (5-FU) and interleukin-2 (IL-2) on non-small cell lung cancer (NSCLC) A549 cells. Materials and Methods: In order to detect whether 5-FU+IL-2 could effectively inhibit tumor growth in vivo, we established an A549-bearing nude mouse model. The cytotoxicity of natural killer (NK) cells was evaluated using a standard chromium release assay. To evaluate the relevance of NK cells in 5-FU+IL-2-mediated tumor inhibitory effects, we depleted NK cells in A549-bearing mice by injecting anti-asialo-GM-1 antibodies. Effects of 5-FU+IL-2 on the expression and promoter activity of NKG2D ligands (MICA/MICB) in A549 cells in vitro were also assessed. Results: In A549-bearing nude mice, combination therapy significantly inhibited tumor growth in comparison with monotherapy with 5-FU or IL-2 and enhanced the recognition and lysis of tumor cells by NK cells. Further study of mechanisms showed that NK cells played a vital role in the anticancer immune response of 5-FU+IL-2 immunochemotherapy. In addition, the combination therapy synergistically stimulated the expression and promoter activity of MICA/MICB. Conclusions: 5-FU and IL-2 immunochemotherapy significantly inhibited tumor growth and activated NK cytotoxicity in vivo, and these effects were partly impaired after depleting NK cells in tumor-bearing mice. Combination treatment of 5-FU and IL-2 upregulated the expression and the promoter activity of MICA/MICB in A549 cells, which enhanced the recognition of A549 cells by NK cells. All of the data indicated that immunochemotherapy of 5-FU and IL-2 may provide a new treatment option for patients with lung cancer.

• IMMUNE NETWORK
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• v.8 no.4
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• pp.130-136
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• 2008

Background: Human cytomegalovirus UL18, a MHC class I homologue, has been considered a natural killer (NK) cell decoy. It ligates LIR-1/ILT2 (CD85j), an NK inhibitory receptor, to prevent lysis of infected target cells. However, precise role of UL18 to NK cell cytotoxicity is yet elusive. Difficulty in clarifying the function of UL18 lies in complication in detecting UL18 mainly due to low level expression of UL18 on the surface and gradual loss of its expression. Methods: To overcome this hurdle, cDNA of cytoplasmic tail-less UL18 was constructed and expressed in swine endothelial cell (SEC). The expression level and its stability in the cell surface were monitored with FACS analysis. Results: Surface expression of UL18 is up-regulated by removing cytoplasmic tail portion from UL18F (a full sequence of UL18). SECs transfected with a cDNA of UL18CY (a cytoplasmic tail-less UL18) stably expressed UL18 molecule on the surface without gradual loss of its expression during 6 week continuous cultures. In the NK cytotoxicity assay, UL18 functions either inhibiting or activating NK cell cytotoxicity according to the source of NK cells. We found that there is individual susceptibility in determining whether the engagement of NK cell and UL18 results in overall inhibiting or activating NK cell cytotoxicity. Conclusion: In this study, we found that cytoplasmic tail is closely related to the regulatory function for controlling surface expression of UL18. Furthermore, by constructing stable cell line in which UL18 expression is up-regulated and stable, we provided a useful tool to clarify exact functions of UL18 on various immune cells having ILT2 receptor.

• Anxiety and mood
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• v.11 no.1
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• pp.54-60
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• 2015

Objective : To translate Center for Epidemiologic Studies Depression Scale (CES-D) into North Korean language and to examine its reliability and validity Methods : North Korean defectors (n=207) recruited from the call center for North Korean defectors participated. Psychiatrists and psychiatric residents interviewed the participants and made the psychiatric diagnoses. Subsequently, the participants completed the CES-D, Impact of Event-Scale-Revised-North Korea (IES-R-NK), Alcohol Use Disorders Identification Test-North Korea (AUDIT-NK), and Brief Psychological State Inventory for North Korean Refugees (BPSI-NKR) questionnaires. Of the original participants, 143 subjects participated in test-retest reliability study after one week. Results : Cronbach's alpha coefficient of CES-D-NK was superior in both males (0.91) and females (0.93). The test-retest correlation coefficient was high (males, 0.64 ; femals, 0.79). Good convergent validity was evident by significant correlations with IER-R-NK, BPSI-NKR-Depression and BPSI-NKR-PTSD, respectively. CES-D-NK had no or weak correlations with AUDIT-NK and BPSI-NKR-Alcohol, showing its discriminant validity. Conclusion : CES-D-NK could be a reliable and valid tool for screening and assessing depressive symptoms of North Korean defectors.

• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.600-606
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• 2012

A Bacillus sp. that produces fibrinolytic enzyme was isolated from Cheonggukjang, a traditional Korean soybean-fermented food. According to 16S rRNA gene base sequencing, the bacillus was identified as a variety of Bacillus subtilis, and named Bacillus subtilis IDCC 9204. Fibrinolytic enzyme NK-IL9204 was stable up to $60^{\circ}C$ and within pH range of 5-10. Purified NK-IL9204 was detected through fibrin zymography. The molecular weight and isoelectric point of the enzyme were estimated to be 27.7 kDa and 6.7 by SDS-PAGE and 2D electrophoresis, respectively. Its amino acid sequence was similar to that of nattokinase (identities 99.5%) and different from that of nattokinase BPN (identities 86.4%). The plasma fibrinolytic activity of NK-IL9204 was measured by euglobulin clot lysis times (ECLT). The NK-IL9204 was orally administered to SD rats for 3 weeks (1,000 FU/rat/day). The ECLT was significantly shortened by supplementation of NK-IL9204.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.2
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• pp.233-238
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• 2002

Moxibustion is one of major healing technique in oriental medicine. It has been widely used in many diseases such as rheumatoid arthritis, Hashimoto disease, breech presentation, etc. However, till now, effects of moxibustion on NK cell activity and relations between sympathetic nerve system(SNS) and the immune alteration induced by moxibustion were not well studied. This study was designed to evaluate effects of moxibustion on NK cell activity and the intervention of SNS in the alteration of NK cell activity induced by moxibustion. Splenic NK cytotoxity was measured in a standard 4-h 51Cr release assay. We measured the NK cytotoxity at after moxibustion stimulation for 1,3,5, and 7 days, and also measured the NK cell cytotoxity after 3 and 7 days burn stimulation with similar temperature. IL-2, IL-4, INF-γ in serum were measured by rat IL-2, IL-4, INF-γ ELISA TEST KIT. To evaluate the effects of sympathectomy on alteration of NK cell cytotoxity, 6-hydroxydopamine(6-OHDA : 5Omg/kg) was used. We showed that NK cell activity of moxibustion stimulation group increased at the 3rd day, and declined at 7th day in comparison with that of contol group. In moxibustion stimulation group, NK cell activity of 3 day stimulation group was significantly higher than sham group. On the contrary, in burn stimulation group, NK cell activity was significantly higher than that of sham groups at 3rd, 7th days. Patterns between moxibustion and burns were different. INF- γ level of 3 days moxibustion stimulation group significantly higher than sham group. IL 2 level among groups were not different. IL-4 was not detected in serum with this method. Sympathectomy abolished the NK cell activity alteration induced by moxibustion. The results suggest that moxibustion induces the alteration of NK cell activity, along with INF-γ and SNS is related to these effects.

• Archives of Pharmacal Research
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• v.28 no.11
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• pp.1282-1286
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• 2005

The in vivo immunomodulatory function of the activity of murine natural killer (NK) cells induced by high mannuronic acid-containing alginate (HMA) was examined. HMA was injected i.p at doses of 25 and 100 mg/kg. The NK activity was 3 times higher with 100 mg/kg HMA than the baseline. In addition, in vitro studies of splenocytes cultured with HMA for 20 h showed a significant increase in NK activity at E:T ratio of 100: 1; a 160$\%$ and 210$\%$ increase at 10 and 100 $\mu$g/mL, respectively. There was a six fold increase in interferon-$\gamma$ production in a postculture of splenocytes with 100 $\mu$g/mL HMA. HMA had no suppressive effects on the lymphocyte function in the presence or absence of mitogens. This suggests that HMA is useful in cancer immunotherapy.

• Nutrition Research and Practice
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• v.11 no.1
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• pp.43-50
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• 2017

BACKGROUND/OBJECTIVES: The present study investigated the hypothesis that a highly pure linear ${\beta}$-1,3-glucan produced by Agrobacterium sp. R259 enhances human natural killer (NK) cell activity and suppresses pro-inflammatory cytokines. SUBJECTS/METHODS: In an eight-week, double-blind, randomized, placebo-controlled clinical trial, 83 healthy adults with white blood cell counts of $4,000-8,000cells/{\mu}L$ were participated and randomly assigned to take two capsules per day containing either 350 mg ${\beta}$-1,3-glucan or placebo. Six participants withdrew their study consent or were excluded due to NK cell activity levels outside the normal range. NK cell activity and serum levels of immunoglobulin G (IgG) and cytokines, such as interferon (IFN)-${\gamma}$, interleukin (IL)-2, IL-4, IL-6, IL-10, IL-12 and tumor necrosis factor (TNF)-${\alpha}$ were measured. RESULTS: NK cell activity and the serum levels of IL-10 were significantly higher from baseline to week 8 in the ${\beta}$-glucan group compared with the placebo group (P = 0.048, P = 0.029). Consumption of ${\beta}$-1,3-glucan also significantly increased NK cell activity compared with placebo after adjusting for smoking and stress status (P = 0.009). In particular, the effect of ${\beta}$-1,3-glucan on NK cell activity was greater in participants with severe stress than in those experiencing mild stress. However, the administration ${\beta}$-1,3-glucan did not significantly modulate the levels of IFN-${\gamma}$, IL-2, IL-4, IL-6, IL-12, TNF-${\alpha}$ and IgG compared with the placebo. CONCLUSION: The results showed that supplementation with bacterial ${\beta}$-1,3-glucan significantly increased NK cell activity without causing any adverse effects. Additionally, the beneficial effect of ${\beta}$-1,3-glucan on NK cell activity was greater in participants experiencing severe stress.

• Journal of Life Science
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• v.8 no.3
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• pp.257-262
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• 1998

Benzo(a)pyrene(B(a)P), an extensively studied polycyclic aromatic hydrocarbon(PAH), is a common contaminant produced through the burning of fossil fuels, particularly coal, and from the exhaust products of internal combustion engines. It produces a wide range of toxicities, including carcinogenicity in experimental animals. B(a)P has been shown to suppress systemic immunity in experimental animals, which may contribute to the growth of the chemical-induced tumors. Using colorimetric MTT assay natural killer(NK) cell-mediated growth inhibition of tomor cell was measured in normal and B(a)P-exposed C57BL/6 mice. Non-adherent splenocytes of normal or B(a)P-exposed mice were cultured with Yac-1 cells at four different effector/target(E/T) cell ratios ranging from 200/1, 100/1, 50/1, and 25/1 in an assay volume of 0.1 ml. After the optical density of culture wells containing MTT solution was measured at a wavelength of 540 nm, the percentage of dead cells relative to the control target cell number was calculated. The NK activity of B(a)P-exposed mice was markedly lower than that of non-exposed mice group at all E/T ratios. These results indicated that suppression of NK cell activity may play a role in allowing for the growth of tumors.

• The Korea Journal of Herbology
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• v.23 no.4
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• pp.81-89
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• 2008

Objectives: In this study, the pharmacological effects of the ethylacetate extract of Ostericum koreanum(North Kangwhal; NK) on allergic inflammation were investigated in activated human mast cells. Methods: North Kangwhal was extracted with 80% methanol for 24 h, and then fractionated with ethylacetate(NK-EtOAc extract). HMC-1 cells, an human mast line, were pre-incubated with different concentrations of NK-EtOAc extract for 30 min, and then stimulated with PMA(50 nM/ml) and A23187($1{\mu}M/ml$) at indicated times. The cell toxicity was determined by MTT assay. The concentrations of prostaglandin E2(PGE2) and cytokines(TNF-${\alpha}$, IL-8) were measured by enzyme-linked immunosorbant assay. Results: NK-EtOAc extract($10{\sim}50{\mu}g/ml$) significantly inhibited the productions of $PGE_2$, TNF-${\alpha}$ and IL-8 in PMA/A23187-stimulated HMC-1 cells without cell toxicity($0{\sim}50{\mu}g/ml$). NK-EtOAc extract also inhibited PMA/A23187-induced phosphorylation of ERK1/2 MAPK and the NF-${\kappa}B$ p65 subunit translocation into the nuclear of HMC-1 cells. Conclusions: This study suggests that NK-EtOAc extract may have an anti-inflammatory property through suppressing the production of inflammatory mediators in activated mast cells and its molecular mechanism underlies the blocking of NF-${\kappa}B$ pathway.