• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.9 no.1
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• pp.15-19
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• 2013

The auxiliary feedwater is an important to remove the heat from the reactor core when the main feedwater system is unavailable. In most initiating events in Probabilistic Safety Assessment(PSA), the operaton of this system is required to mitigate the accidents. For one of domestic nuclear power plants, a design change of a turbine-driven auxiliary feedwater pump(TD-AFWP), pipe, and valves in the auxiliary system is implemented due to the aging related deterioration by long time operation. This change includes the replacement of the TD-AFWP, the relocation of some valves for improving the system availability, a new cross-tie line, and the installation of manual valves for maintenance. The design modification affects the PSA because the system is critical to mitigate the accidents. In this paper, the safety effect of the change of the auxiliary feedwater system is assessed with regard to the PSA view point. The results demonstrate that this change can supply the auxiliary feedwater from the TD-AFWP in the accident with the motor-driven auxiliary feedwater pump(MD-AFWP) unavailable due to test or maintenance. In addition, the change of MOV's normal position from "close" to "open" can deliver the water to steam generator in the loss of offsite power(LOOP) event. Therefore, it is confirmed that the design change of the auxiliary feedwater system reduces the total core damage frequency(CDF).

• Development and Reproduction
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• v.24 no.4
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• pp.297-306
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• 2020

Repetitive changes in the intracellular calcium concentration ([Ca²⁺]i) triggers egg activation, including cortical granule exocytosis, resumption of second meiosis, block to polyspermy, and initiating embryonic development. [Ca²⁺]i oscillations that continue for several hours, are required for the early events of egg activation and possibly connected to further development to the blastocyst stage. The sources of Ca²⁺ ion elevation during [Ca²⁺]i oscillations are Ca²⁺ release from endoplasmic reticulum through inositol 1,4,5 tri-phosphate receptor and Ca²⁺ ion influx through Ca²⁺ channel on the plasma membrane. Ca²⁺ channels have been characterized into voltage-dependent Ca²⁺ channels (VDCCs), ligand-gated Ca²⁺ channel, and leak-channel. VDCCs expressed on muscle cell or neuron is specified into L, T, N, P, Q, and R type VDCs by their activation threshold or their sensitivity to peptide toxins isolated from cone snails and spiders. The present study was aimed to investigate the localization pattern of N and P/Q type voltage-dependent calcium channels in mouse eggs and the role in fertilization. [Ca²⁺]i oscillation was observed in a Ca²⁺ contained medium with sperm factor or adenophostin A injection but disappeared in Ca²⁺ free medium. Ca²⁺ influx was decreased by Lat A. N-VDCC specific inhibitor, ω-Conotoxin CVIIA induced abnormal [Ca²⁺]i oscillation profiles in SrCl₂ treatment. N or P/Q type VDC were distributed on the plasma membrane in cortical cluster form, not in the cytoplasm. Ca²⁺ influx is essential for [Ca²⁺]i oscillation during mammalian fertilization. This Ca²⁺ influx might be controlled through the N or P/Q type VDCCs. Abnormal VDCCs expression of eggs could be tested in fertilization failure or low fertilization eggs in subfertility women.

• Journal of Ginseng Research
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• v.43 no.3
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• pp.452-459
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• 2019

Background: Ginsenoside compound K(C-K), a major metabolite of ginsenoside, exhibits anticancer activity in various cancer cells and animal models. A cell signaling study has shown that C-K inhibited nuclear factor-kappa B ($NF-{\kappa}B$) pathway in human astroglial cells and liver cancer cells. However, the molecular targets of C-K and the initiating events were not elucidated. Methods: Interaction between C-K and Annexin A2 was determined by molecular docking and thermal shift assay. HepG2 cells were treated with C-K, followed by a luciferase reporter assay for $NF-{\kappa}B$, immunofluorescence imaging for the subcellular localization of Annexin A2 and $NF-{\kappa}B$ p50 subunit, coimmunoprecipitation of Annexin A2 and $NF-{\kappa}B$ p50 subunit, and both cell viability assay and plate clone formation assay to determine the cell viability. Results: Both molecular docking and thermal shift assay positively confirmed the interaction between Annexin A2 and C-K. This interaction prevented the interaction between Annexin A2 and $NF-{\kappa}B$ p50 subunit and their nuclear colocalization, which attenuated the activation of $NF-{\kappa}B$ and the expression of its downstream genes, followed by the activation of caspase 9 and 3. In addition, the overexpression of Annexin A2-K320A, a C-K binding-deficient mutant of Annexin A2, rendered cells to resist C-K treatment, indicating that C-K exerts its cytotoxic activity mainly by targeting Annexin A2. Conclusion: This study for the first time revealed a cellular target of C-K and the molecular mechanism for its anticancer activity.

• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.993-1001
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• 2024

The TANDEM project is a European initiative funded under the EURATOM program. The project started on September 2022 and has a duration of 36 months. TANDEM stands for Small Modular ReacTor for a European sAfe aNd Decarbonized Energy Mix. Small Modular Reactors (SMRs) can be hybridized with other energy sources, storage systems and energy conversion applications to provide electricity, heat and hydrogen. Hybrid energy systems have the potential to strongly contribute to the energy decarbonization targeting carbon-neutrality in Europe by 2050. However, the integration of nuclear reactors, particularly SMRs, in hybrid energy systems, is a new R&D topic to be investigated. In this context, the TANDEM project aims to develop assessments and tools to facilitate the safe and efficient integration of SMRs into low-carbon hybrid energy systems. An open-source "TANDEM" model library of hybrid system components will be developed in Modelica language which, by coupling, will extend the capabilities of existing tools implemented in the project. The project proposes to specifically address the safety issues of SMRs related to their integration into hybrid energy systems, involving specific interactions between SMRs and the rest of the hybrid systems; new initiating events may have to be considered in the safety approach. TANDEM will study two hybrid systems covering the main trends of the European energy policy and market evolution at 2035's horizon: a district heating network and power supply in a large urban area, and an energy hub serving energy conversion systems, including hydrogen production; the energy hub is inspired from a harbor-like infrastructure. TANDEM will provide assessments on SMR safety, hybrid system operationality and techno-economics. Societal considerations will also be encased by analyzing European citizen engagement in SMR technology safety.

• Clinical and Experimental Pediatrics
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• v.52 no.4
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• pp.441-445
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• 2009

Purpose : Some patients develop side effects from theophylline even at low serum concentrations. We designed a prospective study to evaluate the side effects of theophylline. Methods : A Prospective, controlled trial study was conducted. The low-dose group received an intravenous continuous aminophylline dose of 5 mg/kg/day on the first day and subsequently 10 mg/kg/day on the following two days. The usual-dose group received 10 mg/kg/day for three days and the control group received normal saline for three days. Heart rate, respiratory rate, serum concentration of theophylline, and four adverse events (irritability, sleep disturbance, jitter, and vomiting) were checked at the time of admission and at 2, 12, 24, 48, and 72 h after the start of aminophylline infusions. Results : Nine patients out of 37 in the low-dose group and six of 21 in the usual-dose group dropped out because of uncontrolled irritability. The serum concentrations of theophylline in dropouts ($3.68{\pm}1.93$ ig/mL) and participants ($4.47{\pm}2.45$ ig/mL) were not significantly different. Irritability was a more frequent side effect in the usual-dose group at 12 h, but there was no difference between the low-dose and usual-dose groups in terms of vomiting, sleep disturbance, and jitter. Most of the severe adverse effects were observed in children below two years of age. Conclusion : Some patients dropped out regardless of the initiating aminophylline dose, especially patients under the age of two years.

• Toxicological Research
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• v.22 no.3
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• pp.283-291
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• 2006

The survival and growth of epithelial cells depends on adhesion to the extracellular matrix. An adhesion signal may regulate the initiation of differentiation, since epidermal keratinocytes differentiate as they leave the basement membrane. A metabolically dead cornified cell envelope is the end point of epidermal differentiation so that this process may be viewed as a specialized form of programmed cell death. In order to investigate the precise cellular signaling events loading to terminal differentiation of keratinocytes, we have utilized HaCaT cells to monitor the biological consequences of $Ca^{2+}$ stimulation and numerous downstream signaling pathways, including activation of the extracellular signal-regulated protein kinase(ERK) pathway and activation of phosphatidylinositol 3-kinase(PI3K). The results presented in this study show that $Ca^{2+}$ function as potent agents for the differentiation of HaCaT keratinocytes, and this differentiation depends or the activation of ERK, Protein kinase B(PKB) and p70 ribosomal protein S6 kinase(p70S6K). Finally, the results show that the expression of Activator protein 1(AP-1; c-Jun and c-Fos) increased following $Ca^{2+}$-mediated differentiation of HaCaT cells, suggesting that ERK-mediated AP-1 expression is critical for initiating the terminal differentiation of keratinocytes.

• Korean Journal of Clinical Pharmacy
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• v.19 no.1
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• pp.18-22
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• 2009

Oxaliplatin is a tolerable and effective drug of choice in the treatment of advanced or metastatic gastric cancer. However, it has many dose-limiting neurotoxicities. This study was performed to assess the incidence and types of oxaliplatin-related neurotoxicities. Sixty-four patients receiving oxaliplatin-involved regimen as salvage therapy on metastatic gastric cancer or as the first-line therapy on advanced gastric cancer were evaluated during the period between September 1, 2006 and February 29, 2008. The patients were treated with oxaliplatin 100 $mg/m^2$ and leucovorin 100 $mg/m^2$ simultaneously as 2-hour-lasting infusion on Day-1 followed by 5-FU 1200 $mg/m^2$ as a 22-hour-lasting continuous infusion both on Day-1 and Day-2 by every other week. We developed questionnaires to evaluate patient-recognized neurotoxic symptoms rather than the observer-described events. Surveys were completed at bedside or via telephone interview. Acute and chronic neurotoxicities were graded according to the National Cancer Institute Common Toxicity Criteria (NCI-CTC, version 3) as well as the Oxaliplatin-specific Neurotoxicity Scale. The Grade-3 neuropathy was reported in 19% of the patients (n=12) and grade-1/2 neuropathy occurred in 70% (n=45). The most common symptom was cold-related dysesthesia (83%) regarded as nociperception by the patients. Some patients (19%) experienced functional impairment affecting activities of daily living such as writing, buttoning, and walking. Even though 74% of the patients (42/57) were prescribed with gabapentin to reduce these peripheral symptoms, it did not appear to derive any benefit from this medication. It is suggested that notify the patients about their oxaliplatin-associated, debilitating symptoms, and educate them any self-care strategy at the initiating phase of the chemotherapy. Moreover, it needs to design the intervention studies regarding the prevention and management of the peripheral neuropathy.

• The Journal of Internal Korean Medicine
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• v.27 no.3
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• pp.639-652
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• 2006

Objective : The etiology of chronic prostatitis is likely multifactorial, resulting from either a cascade of events after an initiating factor or from a variety of etiologic mechanisms. There is substantiating evidence to support the role of the inflammatory responses in its pathogenesis, and the clinical value in the evaluation of therapeutic efficacy. Forsythiae Frucus has been traditionally used in treatment of inflammatory diseases, including of prostatitis and urinary tract inflammation. In this study, we investigated the effects of Forsythiae Frucus on inflammatory cytokines and cyto-pathological alternation in the rat model of chronic non-bacterial prostatitis induced by castration and $17{\beta}$-estradiol treatment. Methods : Two-month-old rats were treated with $17{\beta}$-estradiol after castration for induction of experimental non-bacterial prostatitis. which is similar to human chronic prostatitis in histopathological profiles. Forsythiae Frucus as an experimental specimen, and testosterone as a positive control, were administered orally. The prostates were evaluated by histopathologlcal parameters including the epithelial score and epithelio-stromal ratio for glandular damage. and the expression of inflammatory cytokine genes including interleukin (IL)-$1{\beta}$, IL-5, IL-12, tumor necrosis factor (TNF)-$\alpha$. eotaxin, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2(cox-2). Results : While prostates of control rats revealed severe acinar gland atrophy and stromal proliferation. the rats treated with Forsythiae Frucus showed a diminished range of tissue damage. Epithelial score was improved in the Forsythiae Frucus group over that of the control (P<0.05). The epithelia-stromal ratio was lower in the Forsythiae Frucus group when compared to that of the control (P<0.05). In the reverse transcription-polymerase chain reaction (RT-PCR) of inflammatory cytosine genes. Forsythiae Frucus inhibited the expression of IL-$1{\beta}$, TNF-$\alpha$, iNOS, cox-2 genes, while it modulated the expression of IL-5, which is an anti-inflammatory cytokine. Conclusions : These findings suggest that Forsythiae Frucus may protect the glandular epithelial cells and also inhibit stromal proliferation in association with the immune modulation including the suppression of inflammatory cytokines and increase of anti-inflammatory cytokines. From theses results. we suggest that Forsythiae Frucus could be a useful remedy agents for treating chronic non-bacterial prostatitis.

• Clinical and Experimental Pediatrics
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• v.49 no.9
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• pp.966-971
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• 2006

Purpose : 'Programming' describes the process that stimulus at a critical period of development has lifelong effects. The fact that low birth weight links to the risk of elevated blood pressures in adult life is well known. This study aims to examine whether this link is evident in the newborn by investigating the relationship of the intrauterine growth indices and neonatal blood pressure(BP). Methods : We studied 127 neonates who were born at Ewha Womans' Hospital and their mothers enrolled our cohort study during pregnancy. Data on the mothers and details of the birth records were tracked and collected from medical charts. Neonatal BP was measured within 24 hours after birth. Results : Neonatal SBP was positively correlated to intrauterine growth indices; birth weight(BW)(r=0.4), head circumference(HC)(r=0.4), and birth height(r=0.3). However, an inverse relationship existed, between HC/BW ratio and neonatal SBP(r=-0.4). After adjusting for the baby's sex, maternal BP, and gestational age, neonatal SBP still associated with intrauterine growth indices. SBP was 7 mmHg higher in the highest BW group(${\geq}90percentiles$) compared to the lowest group(<10 percentiles). On the other hand, SBP was 17 mmHg lower in the highest HC/BW group(${\geq}90percentiles$) compared in the lowest group(<10 percentiles). Conclusion : This study could not find the evidence that intrauterine growth retardation affect on elevated neonatal BP. It suggests that the initiating events of BP programming may occur during postnatal growth period. To identify the critical starting period that intrauterine growth retardation leads to elevated BP, a study tracking BP changes from birth to childhood is required.