• Nuclear Engineering and Technology
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• 제40권3호
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• pp.183-190
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• 2008

Pyroprocessing is the optimal means of treating spent metal fuels from metal fast fuel reactors and is proposed as a potential option for GNEP in order to meet the requirements of the next generation fuel cycle. Currently, efforts for research and development are being made not only in the U.S., but also in Asian countries. Electrorefining, cathode processing by distillation, injection casting for fuel fabrication, and waste treatment must be verified by the use of genuine materials, and the engineering scale model of each device must be developed for commercial deployment. Pyroprocessing can be effectively extended to treat oxide fuels by applying an electrochemical reduction, for which various kinds of oxides are examined. A typical morphology change was observed following the electrochemical reduction, while the product composition was estimated through the process flow diagram. The products include much stronger radiation emitter than pure typical LWR Pu or weapon-grade Pu. Nevertheless, institutional measures are unavoidable to ensure proliferation-proof plant operations. The safeguard concept of a pyroprocessing plant was compared with that of a PUREX plant. The pyroprocessing is better adapted for a collocation system positioned with some reactors and a single processing facility rather than for a centralized reprocessing unit with a large scale throughput.

• Journal of Microbiology and Biotechnology
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• 제31권3호
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• pp.475-482
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• 2021

Prodigiosins, which are natural tripyrrole red pigments and synthetic derivatives, reportedly have multiple biological effects mainly on various types of cancer cells. However, the effects of bacterial prodigiosin on non-cancerous HaCaT human skin keratinocytes have not been reported. Therefore, the present study aimed to investigate the functional activities of prodigiosin derived from cultures of the bacterium Hahella chejuensis in HaCaT cells. Cell viability, the cell proliferation rate, and reactive oxygen species (ROS) production in vitro were assayed following treatment of HaCaT cells with prodigiosin. Prodigiosin did not cause cytotoxicity and notably increased proliferation of HaCaT cells. Furthermore, prodigiosin reduced ultraviolet (UV) irradiation-induced ROS production and the inflammatory response in HaCaT cells. More importantly, prodigiosin reduced matrix metalloproteinase-9 expression and increased collagen synthesis in UV-irradiated HaCaT cells, demonstrating that it elicits anti-aging effects. In conclusion, our results reveal that H. chejuensis-derived prodigiosin is a potential natural product to develop functional cosmetic ingredients.

• 산업경영시스템학회지
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• 제39권3호
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• pp.47-55
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• 2016

The proliferation of the Internet and related technologies has led to a new form of distribution channels, namely online retailers. The conventional offline and the new online retailers have different transaction costs perceived by the consumers in the following perspectives: the accessibility to the product information, the traffic cost and the opportunity cost for the time to visit the store, the delivery time and the possibility of 'touch and feel' to test the quality of the product. In particular, the online retailers have lower distribution cost structure in that they do not have physical stores, which results in lower selling price. Thus they continuously offer price competition against offline retailers using the lower selling cost as competitive weapon. Moreover the emergence of the social commerce is likely to intensify the competition between the online and offline retailers. To survive in this fierce competition, the offline retailers are trying to defend their business interests by sticking to offline transaction in anticipation of increased customer loyalty, customer's preference for 'touch and feel' style shopping, and others. Despite of these efforts, customers who touch and feel a product in an offline store but purchase the product through an online retailer are increasing. To protect such customers, recently, some of the offline retailers began to provide the mobile discount service (MDS) which enables the offline customers to purchase a product at a discounted price through the mobile applications. In business competitions, the price discount strategy is usually considered to secure more market share at the cost of lower profit. In this study, however, we analyze the effect of MDS as a weapon for securing more profit. To do this, we set up a game model between the online and offline retailers which incorporates the effect of the MDS. By numerically analyzing the Nash equilibrium of the game, some managerial implications for using the MDS for more profit are discussed.

• 한국산학기술학회논문지
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• 제10권11호
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• pp.3373-3383
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• 2009

본 연구는 성공적으로 제품 다양성을 증가시키기 위한 신제품 개발 조직의 특성을 분석하는 데 있다. 본 연구는 플랫폼 및 파생제품 개발을 위한 조직의 구조적 특성을 개별적으로 고려하여, 제품군 (product family) 전체의 성과에 미치는 영향을 분석하고자 한다. 본 연구에서는, 조직 내 구성원 및 그룹간의 관계를 규정짓는 3가지 요인(분권화, 공식화, 전문화)과 함께, 개발 관련 조직 간 공간적 근접성 (spatial proximity)을 조직의 구조적 특성을 파악하는 요인으로 사용하고자 한다. 본 연구는 국내 103개 제조업체로부터 수집한 설문응답 분석에 기초하였다. 조직 구조적 특성은 기업의 제품 다양성 정도와 신제품 개발 성과 간의 관계를 매개하는 것으로 나타났다. 특히 본 연구결과는 기존 신제품 개발 조직 연구와 상반되는 몇 가지 결과를 보고 주고 있다. 제품 다양성을 증가시키는 기업에게 있어, 플랫폼 제품 개발 과정의 공식화 및 파생 제품 개발과정의 분권화는 제품군 전체의 성과를 향상시켜 준다. 본 연구는 개발 조직의 공간적 근접성이 성공적으로 제품 다양성을 증가시키는 데 중요한 조직요소라는 것을 증명하였다.

• 한국축산식품학회지
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• 제34권1호
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• pp.88-98
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• 2014

Total spleen lymphocytes, lymphocyte proliferation, tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and interleukin-10 (IL-10) in spleen lymphocyte culture were studied in malnourished Wistar rats fed with goat milk yoghurt. Malnourished rats were created by using standard feed restriction as much as 50% of normal rats for 21 d. Goat milk yoghurt containing three types of microorganism e.g., Lactobacillus acidophilus, Sterptococcus thermophilus and Bifidobacterium longum derived from Lacto-B culture in powder form. After 21 d, the rats continued to receive restricted feeding and supplemented with goat milk yoghurt for 7 d. Total splenocytes were counted by hemocytometer. Splenocytes proliferation was expressed as stimulation index, whereas the TNF-${\alpha}$ and IL-10 of spleen lymphocyte culture were measured by ELISA technique. The total number of splenocytes and stimulation index of splenocytes in moderate malnourished and normal rats supplemented with goat milk yoghurt was not significantly different. The level of TNF-${\alpha}$ in the rat supplemented with goat milk yoghurt was lower (p<0.05) than the control group, whereas the level of IL-10 in the rat supplemented with goat milk yoghurt was higher (p<0.05) than the control group. In conclusion, goat milk yoghurt supplementation in malnourished rats could decrease TNF-${\alpha}$ as a representation of the pro-inflammatory cytokine, while it increases IL-10 as a representation of the anti-inflammatory cytokine.

• KSBB Journal
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• 제16권6호
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• pp.579-591
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• 2001

The cell growth inhibitor effect of cervical cancer cells was investigated by liposome mediated transfection (pRcCMVp53/lipofectin) and by transfection using adenovirus (AdCMVp57). The papilloma virus cancer cell lines we used in this study were HPV16 positive, having inhibiter gene, wild p53 gene, CaSki, SiHa, HPV18 positive HeLa, HeLaS3 and HPV negative C33A, HT3. LacZ gene of E.coli was used as the marker gene for the transfection efficiency. The effect on the inhibition of tumor cell growth was measured by cell count and cell viability though ELISA analysis and MTT assay. The inhibition of tumor cell growth was confirmed by measuring each assay for six days, comparing with the normal control cell growth. The cell growth of cervical cancer calls by transfection was significantly reduced and showed tittle differences among the cell lines. To eliminate the potential problem of Ad(adenovirus) contamination during rAAV production, rAAV can be produced by a triple transfection of vector plasmic, packaging plasmid, and adenovirus helper plasmid. To examine the helper functions of Ad plasmids on the production of rAAV vector, we carried out cotransfection of three plasmids, AAV vector, packaging construct, and Ad helper plasmids. The optimized transfection condition for calcium phosphate method is 25ug of total DNA per 10-cm-diameter plate of 293 cell. We found that rAAV yields peaked at 48hr after Ad infection. The titer of rAAV was measured by the dot blot analysis to measure the number of particles/ml based on the quantification of viral DNA. Recent1y, Kombucha(fungi) was identified as a very potent antileukefic agent. In the present study, effect of natural toxin(plankton) and Kombucha is PSP(GTXI-3, neoSTX), on various MTT assay cervical cancer cell line. Toxin(GTX 1-3, neoSTX) also inhibited the proliferation in primary cervical cancer calls in a dose-dependent toxin concentration. These results showed that toxin was very potent in inhibiting the proliferation of cervical cancer calls in vitro. Toxins and Kombuoha exhibited a dose dependent inhibition of cellular proliferation in cancer cell line.

• Natural Product Sciences
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• 제26권2호
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• pp.136-143
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• 2020

Psoriasis is one of the most common inflammatory skin disorders, with a global prevalence of 2% - 3%. It is an autoimmune skin disorder characterized by excessive generation of plaques on the skin with typical long-lasting red, itchy, and scaly lesions. In this study, we aimed to elucidate the anti-psoriatic effect of the methanolic extract of Persicaria senticosa (PS), a bioactive edible plant extract used in traditional medicine, using a mouse model of imiquimod (IMQ)-induced psoriasis. The daily topical application of IMQ could induce human psoriasis-like lesion. The extract ameliorated IMQ-induced psoriasis. Furthermore, hematoxylin and eosin staining and the Psoriasis Area and Severity Index (PASI) scores indicated that topical application of PS led to an improvement in erythema, scaling, and thickness scores of the mouse dorsal skin and a considerable decrease in the epidermal thickness of the ear and dorsal skin in the IMQ-induced psoriatic mouse model. We also studied the effect of PS on the proliferation of keratinocytes using HaCaT cells. The extract inhibited cell proliferation and IL-6 and pSTAT3 expression induced by M5 cocktail (comprising interleukin [IL]-1α, IL-17A, IL-22, oncostatin M, and tumor necrosis factor-α) in HaCaT cells. Thus, PS might serve as a potential therapeutic agent for the treatment of psoriasis.

• Nutrition Research and Practice
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• 제11권4호
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• pp.275-280
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• 2017

BACKGROUND/OBJECTIVES: Re-epithelialization has an important role in skin wound healing. Astaxanthin (ASX), a carotenoid found in crustaceans including shrimp, crab, and salmon, has been widely used for skin protection. Therefore, we investigated the effects of ASX on proliferation and migration of human skin keratinocyte cells and explored the mechanism associated with that migration. MATERIAL/METHOD: HaCaT keratinocyte cells were exposed to $0.25-1{\mu}g/mL$ of ASX. Proliferation of keratinocytes was analyzed by using MTT assays and flow cytometry. Keratinocyte migration was determined by using a scratch wound-healing assay. A mechanism for regulation of migration was explored via immunocytochemistry and western blot analysis. RESULTS: Our results suggest that ASX produces no significant toxicity in human keratinocyte cells. Cell-cycle analysis on ASX-treated keratinocytes demonstrated a significant increase in keratinocyte cell proliferation at the S phase. In addition, ASX increased keratinocyte motility across the wound space in a time-dependent manner. The mechanism by which ASX increased keratinocyte migration was associated with induction of filopodia and formation of lamellipodia, as well as with increased Cdc42 and Rac1 activation and decreased RhoA activation. CONCLUSIONS: ASX stimulates the migration of keratinocytes through Cdc42, Rac1 activation and RhoA inhibition. ASX has a positive role in the re-epithelialization of wounds. Our results may encourage further in vivo and clinical study into the development of ASX as a potential agent for wound repair.

• Journal of Animal Science and Technology
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• 제64권1호
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• pp.123-134
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• 2022

Toll-like receptors (TLRs), as a part of innate immunity, plays an important role in detecting pathogenic molecular patterns (PAMPs) which are structural components or product of pathogens and initiate host defense systems or innate immunity. Precise negative feedback regulations of TLR signaling are important in maintaining homeostasis to prevent tissue damage by uncontrolled inflammation during innate immune responses. In this study, we identified and characterized the function of the pancreatic progenitor cell differentiation and proliferation factor (PPDPF) as a negative regulator for TLR signal-mediated inflammation in chicken. Bioinformatics analysis showed that the structure of chicken PPDPF evolutionarily conserved amino acid sequences with domains, i.e., SH3 binding sites and CDC-like kinase 2 (CLK2) binding sites, suggesting that relevant signaling pathways might contribute to suppression of inflammation. Our results showed that stimulation with polyinosinic:polycytidylic acids (Poly [I:C]), a synthetic agonist for TLR3 signaling, increased the mRNA expression of PPDPF in chicken fibroblasts DF-1 but not in chicken macrophage-like cells HD11. In addition, the expression of pro-inflammatory genes stimulated by Poly(I:C) were reduced in DF-1 cells which overexpress PPDPF. Future studies warrant to reveal the molecular mechanisms responsible for the anti-inflammatory capacity of PPDPF in chicken as well as a potential target for controlling viral resistance.

• The Korean Journal of Physiology and Pharmacology
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• 제26권5호
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• pp.389-396
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• 2022

The increased expression of receptors for advanced glycation end-product (RAGE) is known as a key player in the progression of vascular remodeling. However, the precise signal pathways regulating RAGE expression in vascular smooth muscle cells (VSMCs) in the injured vasculatures are unclear. Given the importance of mitogen-activated protein kinase (MAPK) signaling in cell proliferation, we investigated the importance of MAPK signaling in high-mobility group box 1 (HMGB1)-induced RAGE expression in VSMCs. In HMGB1 (100 ng/ml)-stimulated human VSMCs, the expression of RAGE mRNA and protein was increased in association with an increase in AGE-induced VSMC proliferation. The HMGB1-induced RAGE expression was attenuated in cells pretreated with inhibitors for ERK (PD98059, 10 μM) and p38 MAPK (SB203580, 10 μM) as well as in cells deficient in ERK and p38 MAPK using siRNAs, but not in cells deficient of JNK signaling. In cells stimulated with HMGB1, the phosphorylation of ERK, JNK, and p38 MAPK was increased. This increase in ERK and p38 MAPK phosphorylation was inhibited by p38 MAPK and ERK inhibitors, respectively, but not by JNK inhibitor. Moreover, AGE-induced VSMC proliferation in HMGB1-stimulated cells was attenuated in cells treated with ERK and p38 MAPK inhibitors. Taken together, our results indicate that ERK and p38 MAPK signaling are involved in RAGE expression in HMGB1-stimulated VSMCs. Thus, the ERK/p38 MAPK-RAGE signaling axis in VSMCs was suggested as a potential therapeutic target for vascular remodeling in the injured vasculatures.