• Environmental Analysis Health and Toxicology
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• v.11 no.1_2
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• pp.49-57
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• 1996

The production of reactive oxygen species on addition of hexavalent chromium (potassium dichromate, $K_2Cr_2O_7$ ) to lung cells in culture was studied using flow cytometer analysis. A Coulter Epics Profile flow cytometer was used to detect the formation of reactive oxygen species after $K_2Cr_2O_7$ was added to A549 cells grown to confluence. The cells were loaded with the dye, 2',7'-dichlorofluorescein diacetate, after which cellular esterases removed the acetate groups and the dye was trapped intracellularly. Reactive oxygen species oxidized the dye, with resultant fluorescence. Increased doses of Cr(VI) caused increasing fluorescence (10-fold higher than background at 200 gM). Addition of Cr(III) compounds, as the picolinate or chloride, caused no increased fluorescence. Electron paramagnetic resonance (EPR) spectroscopic studies indicated that three (as yet unidentified) spectral "signals" of the free radical type were formed on addition of 20, 50, 100 and 200 gM Cr(VI) to the A549 cells in suspension. Two other EPR 'signals" with the characteristics of Cr(V) entities were seen at field values lower than the standard free radical value. radical value.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6121-6125
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• 2014

Background: Prostate-specific antigen (PSA) is a potential biomarker for early detection of prostate cancer (PCa) but its level is known to be affected by many background factors and roles of ubiquitous toxicants have not been determined. Endocrine disrupting chemicals (EDCs) are ubiquitous reproductive toxicants used in consumer products, which promote tumor formation in some reproductive model systems by binding to AhR, but human data on its expression in prostate cancer as well as its association with PSA levels are not clear. This study aimed to evaluate the expression levels of AhR and its association with serological levels of PSA and to detect possible effects of background factors and EDC exposure history on PSA levels in PCa cases. Materials and Methods: A cross-sectional study was conducted on the tissue levels of AhR and serum levels of PSA in 53 PCa cases from 2008-2011 and associations between each and background and lifestyle related factors were determined. Results: Although the AhR was overexpressed in PCa and correlated with the age of patients, it did not correlate with PSA levels.Of nutritional factors, increased intake of polysaturated fats and fish in the routine regimen of PCa cases increased the PSA levels significantly. Conclusions: AhR overexpression in PCa pontws to roles of EDCs in PCa but without any direct association with PSA levels. However, PSA levels are affected by exposure to possible toxicants in foods whichneed to be assessed as possible risk factors of PCa in future studies.

• Journal of Chest Surgery
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• v.50 no.1
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• pp.30-35
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• 2017

Background: Tapered grafts, which have a smaller diameter on the arterial side, have been increasingly used for arteriovenous fistula (AVF) formation. We compared the outcomes of 4-6-mm tapered and 6-mm straight forearm loop arteriovenous grafts. Methods: A total of 103 patients receiving forearm loop arteriovenous grafts between March 2005 and March 2015 were retrospectively analyzed and separated into 2 groups (group A, 4- to 6-mm tapered grafts, n=78; group B, 6-mm straight grafts, n=25). In each group, complications and patency rates after surgery were assessed. Results: Clinical characteristics and laboratory results, except for cerebrovascular disease history (group A, 7.7%; group B, 28.0%; p=0.014), were similar between the groups. No significant differences were found for individual complications. Kaplan-Meier survival analysis revealed no significant differences in 1-year, 3-year, and 5-year patency rates between groups (61.8%, 44.9%, and 38.5% vs. 62.7%, 41.1%, and 35.3%, respectively). Conclusion: We found no significant differences in complication and patency rates between the tapered and straight graft groups. If there are no differences in complication and patency between the two graft types, tapered grafts may be a valuable option for AVF formation in light of their other advantages.

• Journal of Korea Society of Industrial Information Systems
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• v.11 no.5
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• pp.225-235
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• 2006

Not a few nations have tried to copy the success of Silicon Valley since 1980's. Research of information communication industry cluster has emerged in Korea since 1990. In this background this paper thoroughly reviewed scholarly literature related to industry cluster with an attempt to extract dominant factors for cluster formation, and designed a survey instrument to measure the status-quo of cluster formation of software industry in Chungbuk Province Korea, as an example. Based on the results from statistical analysis a strategic scheme was proposed to propel software industry cluster formation in the region.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.1
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• pp.82.2-82.2
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• 2011

Infra-Red Dark Clouds (IRDCs) seen silhouette against the bright Galactic background in mid-IR are a class of interstellar clouds that are dense and cold with very high column densities. While IRDCs are believed to be the precursors to massive stars and star clusters, individual IRDCs show diverse star forming activities within them. We report a remarkable example of such cloud, the IRDC at ${\Gamma}53.2^{\circ}$, and star formation activity in this cloud. The IRDC was previously identified in part as three separate, arcmin-size clouds in the catalogue of MSX IRDC candidates, but we found that the IRDC is associated with a long, filamentary CO cloud at 2 kpc from the Galactic Ring Survey data of $^{13}CO$ J = 1-0 emission, and that its total extent reaches ~ 30pc. The Spitzer MIPSGAL 24mm data show a number of reddened mid-IR sources distributed along the IRDC which are probably young stellar objects (YSOs), and the UWISH2 $H_2$ data (2.122mm) reveal ubiquitous out flows around them. These observations indicate that the IRDC is a site of active star formation with YSOs in various evolutionary stages. In order to investigate the nature of mid-IR sources, we have performed photometry of MIPSGAL data, and we present a catalogue of YSOs combining other available point source catalogues from optical to IR. We discuss the evolutionary stages and characteristics of YSOs from their IR colors and spectral energy distributions.

• Journal of People, Plants, and Environment
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• v.23 no.4
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• pp.465-473
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• 2020

Background and objective: Aronia melanocarpa, called black chokeberry, is a natural product belonging to the family rosaceae, and is known to contain polyphenolic antioxidants including cyanidin-3-galactoside, cyanidin-3-arabinoside, cyanidin-3-xyloside, and cyanidin-3-glucoside Because of the abundance of anthocyanins, Aronia has been studied to be used in various industries. Methods: Aronia melanocarpa extract was treated 24 hours a day to RAW 264.7 cells with inflammations induced by LPS. After extracting total RNA, the amount of inflammatory cytokine expression was measured using RT-PCR. After processing the Aronia liposome using Aronia extract and the layer-by-layer electrostatic deposition method in keratinocyte cells at the same time, we checked the synthesis of Hyaluronic acid enhanced through the formation of Aronia liposome using ELISA. Results: The treatment of Aronia extract in inflammation-induced RAW 264.7 cells conducted to check the anti-inflammatory efficacy of Aronia extract inhibited inflammatory cytokines including TLR4, TNF-α, IL-1β, COX-2, and iNOS and increased the mRNA expression of HAS2 genes related to moisturizing. Based on the anti-inflammatory and moisturizing effect of Aronia extract, the Aronia liposome technology was introduced to Aronia extract to produce Aronia liposome. Conclusion: The liposome formation of Aronia extract is expected to be used as a functional material in treating various inflammatory skin diseases by controlling the moisture content of the corneocytes by increasing the expression rate of genes associated with the synthesis of hyaluronic acid, while retaining the efficacy of its components.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.20 no.1
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• pp.36-41
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• 2009

Background and Objectives: Topical administration of mitomycin-C (MMC) has been reported to reduce or delay scar formation in airway surgery. However, it is not infrequent to experience recurrent stenosis or adhesion of operative wound even after a meticulous MMC application during the laryngeal surgery. Therefore we aimed to evaluate the effectiveness of repeated postoperative MMC applications and the technical feasibility of MMC applications to the laryngeal wound at an outpatient clinic. Methods: We reviewed medical records of 13 consecutive patients who received office-based MMC applications after laryngeal airway surgery at Samsung Medical Center, Seoul, Korea. The patients were grouped into 3 categories according to the site of surgical wound and the purpose of MMC application; group I : supraglottic stenosis (n=5), group II : cordectomy and arytenoidectomy site granulation prevention (n=3), Group III : laryngeal web prevention (n=5). Outcomes in each group and adverse effects of repeated MMC applications were evaluated. Results: Office-based MMC application was successfully performed one to four times with a week interval for each patient. No significant complications were observed except slightly decreased mucosal wave in one female patient who received 4 times of MMC application at the anterior commissure of vocal fold. Repeated MMC applications at the outpatient clinic resulted in wide or acceptable supraglottic airway in group I, clean wound healing without granulation formation in group II, and negligible or no web formation at the anterior commissure in group III. Conclusion : Office-based topical administration of MMC to the larynx was technically feasible. Postoperative repeated MMC applications were effective to reduce recurrent stenosis or adhesion of supraglottic structures, to prevent granuloma formation after laser arytenoidectomy and glottic web formation after anterior commissure resection.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.3 no.3
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• pp.1-15
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• 2008

The paper discusses application of soft OR methodologies, which have been developed for last decades centered in European OR communities, to strategy formation process. It is shown that there is strong similarity in understanding of strategy formation between descriptive school of strategy and the research trend of soft OR. The focus and philosophical background of cognitive school of strategy, in particular, share much in common with soft OR school. The analysis and overview of several soft OR methodologies are introduced. It is also proposed that SODA can be utilized more directly to the strategy formation process. However, it is also noted in this paper that the epistemological issues should be considered and resolved for fluent investigation of soft OR methodologies in relation with existing rich strategic research works, for soft OR adopts interpretative research methods while strategy research generally lies on positivistic approaches.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2007.11a
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• pp.153-158
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• 2007

Background: Naturally occurring antioxidants were used to regulate the skin damage caused by ultraviolet (UV) radiation because several antioxidants have demonstrated that they can inhibit wrinkle formation through prevention of matrix metalloproteinases (MMPs) and/or increase of collagen synthesis. We examined the effect of oral administration of the antioxidant mixture ("L-Skin Care") on UVB-induced wrinkle formation. In addition, we investigated the possible molecular mechanisms of photoprotection against UVB through inhibition of collagen-degrading MMP activity or through enhancing of pro collagen synthesis in mouse dorsal skin. Methods: Female SKH-l hairless mice were orally administrated "L-Skin Care" (test group) or vehicle (control group) for 10 weeks with UVB irradiation by three times a week. The intensity of irradiation was gradually increased from 30 to $180mJ/cm^2$. Microtopographic and histological assessments of the dorsal skins were carried out at the end of 10 weeks to evaluate wrinkle formation. Western blot analysis and EMSA were also carried out to investigate the changes in the balance of collagen synthesis and collagen degradation. Results: Our "L-Skin Care" significantly reduced UVB-induced wrinkle formation, accompanied by significant reduction of epidermal thickness, and UVB-induced hyperplasia, acanthosis and hyperkeratosis. Oral administration of "L-Skin Care" significantly prevented UVB-induced expressions of MMPs, mitogen-activated protein (MAP) kinases and activation of activator protein (AP)-1 transcriptional factor in addition to enhanced type I procollagen and transforming growth factor-$\beta$ (TGF-$\beta$) expression. Conclusion: Oral administration of "L-Skin Care" significantly inhibited wrinkle formation caused by chronic UVB irradiation through significant inhibition of UVB-induced MMP activity accompanied with enhancement of collagen synthesis.

• Journal of Ginseng Research
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• v.47 no.2
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• pp.246-254
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• 2023

Background: Here, we aimed to assess the inhibitory effect of a new compound from Panax ginseng on the migration of human ovarian cancer cells and tube formation of human umbilical vein endothelial cells (HUVECs). Methods: A new compound, ginsenglactone A (1), was isolated from ginseng roots, together with seven known compounds (2-8). Spectroscopic data were used to elucidate the chemical structure of 1. The tubular structure formation in HUVECs was assessed by Mayer's hematoxylin staining. The migration of A2780 cells was evaluated using the scratch wound healing assay. Results: HUVECs treated with 1 had the statistically significant decrease in tubular structure formation compared to the HUVECs treated with compounds 2-8. This effect was enhanced by co-treatment with inhibitors for phosphatidylinositol 3-kinase (PI3K) (LY294002) and extracellular signal-regulated kinase (ERK) (U0126). Treatment with 1 decreased the expression of phosphorylation of ERK, PI3K, vascular endothelial growth factor receptor2 (VEGFR2), Akt, and mammalian target of rapamycin (mTOR). In addition, the ability of A2780 cells to cover the scratched area were also decreased. This effect was enhanced by co-treatment with U0126. Lastly, treatment with 1 decreased the phosphorylation of ERK, matrix metalloproteinase-9 (MMP-9), and MMP-2. Conclusion: These results suggest that ginsenglactone A is a potential inhibitor of HUVEC tubular structure formation and A2780 cellular migration, which may be helpful for understanding its anticancer mechanism.