• Molecules and Cells
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• v.46 no.3
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• pp.165-175
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• 2023

The transcription factor Nrf2 was originally identified as a master regulator of redox homeostasis, as it governs the expression of a battery of genes involved in mitigating oxidative and electrophilic stress. However, the central role of Nrf2 in dictating multiple facets of the cellular stress response has defined the Nrf2 pathway as a general mediator of cell survival. Recent studies have indicated that Nrf2 regulates the expression of genes controlling ferroptosis, an iron-and lipid peroxidation-dependent form of cell death. While Nrf2 was initially thought to have anti-ferroptotic function primarily through regulation of the antioxidant response, accumulating evidence has indicated that Nrf2 also exerts anti-ferroptotic effects via regulation of key aspects of iron and lipid metabolism. In this review, we will explore the emerging role of Nrf2 in mediating iron homeostasis and lipid peroxidation, where several Nrf2 target genes have been identified that encode critical proteins involved in these pathways. A better understanding of the mechanistic relationship between Nrf2 and ferroptosis, including how genetic and/or pharmacological manipulation of Nrf2 affect the ferroptotic response, should facilitate the development of new therapies that can be used to treat ferroptosis-associated diseases.

• Korean Journal of Childcare and Education
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• v.19 no.2
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• pp.1-20
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• 2023

Objective: The present study aimed to investigate the sequential mediation effects of creative home environment and preschoolers' playfulness on the relationship between mothers' play beliefs and preschoolers' happiness. Methods: The subjects of this study were 233 preschoolers between the ages of 3 and 5 and their mothers. Mothers were asked to complete a questionnaire that assessed their beliefs about play, the creative home environment they provided, as well as their child's playfulness and happiness. The data collected were analyzed using the SPSS Process Macro program to investigate the sequential mediating effects. Results: The study found that the mothers' play support beliefs were directly associated with their preschoolers' happiness. Additionally, the creative home environment was found to mediate the relationship between the mother's play beliefs and their preschooler's happiness. The children's playfulness was also identified as a mediator in the relationship between the mother's play beliefs and their preschooler's happiness. Furthermore, the findings of this study indicated that the relationship between the mother's play beliefs and preschoolers' happiness was sequentially mediated by the creative home environment and preschoolers' playfulness. Conclusion/Implications: Findings of this study provide insights into the potential development of a parent education program aimed at modifying mothers' play beliefs and the home environment.

• The Journal of Pediatrics of Korean Medicine
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• v.11 no.1
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• pp.249-273
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• 1997

Hyunggyeyungyotang has been used for treatment of sinusitis and otitis media in oriental medicine since ancient times. It is reported that Hyunggyeyungyotang has good effects on inflammatory and allergic diseases of otorhinolaryngology in clinical medicine. Kamihyunggyeyungyotang was made by adding several herbs to Hyunggyeyungyotang which has such good effects. To investigate the effects of Hyunggyeyungyotang and Kamihyunggyeyungyotang on inflammatory, algesic and allergic diseases, the author examined the analgesic effect by acetic acid reaction, studied the anti-inflammatory effect through the experiments of the protein thermo-denaturation and circumscribed edema. Besides researched the anti-allergic effect through the vascular permeability response to Chemical Mediator and the delayed type hypersensitivity response to Picryl Chloride. The obtained results were as follows ; 1. In the analgesic effect of Hyunggyeyungyotang and Kamihyunggyeyungyotang extract by acetic acid method, both of the sample groups showed the analgesia, but didn't show useful effect. 2. In the anti-inflammatory effect on the protein thermo-denaturation, the sample groups revealed the inhibitory effect in proportion to concentration as compared with the control group. 3. In the inhibitory action on circumscribed edema induced by Caraggeenin, both of Hyunggyeyungyotang and Kamihyunggyeyungyotang administration showed the significant effect after 4 hours in comparison to the control group. 4. In the delayed type hypersensitivity response to Picryl Chloride, both of the sample groups revealed the significant effects. 5. Both of the sample groups decreased the vascular permeability induced by Histamine in comparison with the control group, but the significancy was admitted in only Hyunggyeyungyotang administration. According to above results, Hyunggyeyungyotang and Kamihyunggyeyungyotang are considered to be used for treament of the inflammatory diseases including sinusitis.

• Journal of Korean Medicine Rehabilitation
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• v.23 no.2
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• pp.49-61
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• 2013

Objectives : This study was conducted to determine whether or not Kangwhaldoche-tang(Qianghuodaozhi-tang) (KDT) aqueous extracts can protect articular cartilage losses on the Freund's complete adjuvant(FCA)-induced rat rheumatoid arthritis. Methods : 520, 260 or 130 mg/kg of KDT were orally administered once a day for 14 days from 14 days after FCA treatments, and 15 mg/kg of dexamethasone was intraperitoneally administered as reference drug in this experiment. Changes on the body weight, knee circumferences, gross arthritis score, inflammatory tissue prostaglandin(PG) $E_2$ levels were monitored with cartilage collagen components and glucosaminoglycans(GAGs) compositions - chondroitin sulphate, heparin sulphate and hyaluronic acid in the present study. Results : As results of FCA treatment, classic rheumatoid arthritis featuring dramatic decreases of the body weights, cartilage collagen and GAGs contents with increases of the knee circumferences, gross arthritis scores and inflammatory tissue $PGE_2$ levels, were demonstrated in the present study. However, these changes from FCA - induced rheumatoid arthritis were clearly inhibited by treatment of dexamethasone and all three different dosages of KDT. Although overall anti-inflammatory effects of KDT 520 mg/kg were lowered than those of dexamethasone 15 mg/kg treated rats, KDT 520 mg/kg showed more favorable preserve effects on the cartilage GAGs and KDT 260 mg/kg treated rats showed similar preserve effects as compared with dexamethasone 15 mg/kg in this experiment. Conclusions : The present results supported that over 75 mg/kg of KDT showed favorable anti-arthritic effects on the FCA-induced arthritis mediated by suppression of $PGE_2$, representative inflammatory mediator, and may help improve rheumatoid arthritis.

• Journal of Korean society of Dental Hygiene
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• v.18 no.4
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• pp.489-499
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• 2018

Objectives: The purpose of this study was to investigate the mediating effects of burnout and to identify the moderating effects of individual factors and organizational factors on the relationship between emotional dissonance and job satisfaction. Methods: This cross-sectional study included 270 dental hygienists working full-time at dental care facilities. The data on the socio-demographic characteristics, emotional dissonance, burnout, job satisfaction, and individual and organizational factors were collected. The individual (self-efficacy and ego resilience) and organizational (social support, organizational support and wage satisfaction) factors were considered as the moderating variable. For statistical analyses, t-test, one-way ANOVA and multiple linear regression were used. Results: Burnout was found to be a significant mediator on the relationship between emotional dissonance and job satisfaction(p<0.001). The variables moderating the relationship between emotional dissonance and burnout were identified as social support, organizational support and wage satisfaction (p<0.05), while the variables moderating the relationship between burnout and job satisfaction were wage satisfaction and ego resilience (p<0.05). Conclusions: To prevent the decrease in job satisfaction due to emotional dissonance, the management of dental care facilities should have a better understanding of burnout in dental hygienists, which requires individual and organizational efforts to be moderated. In addition, as organizational support has been identified as the factor mitigating the negative effects of emotional dissonance, it is highly necessary to adopt the preceptor system, improve communication systems and expand welfare policies of organizations.

• Journal of dental hygiene science
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• v.20 no.4
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• pp.213-220
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• 2020

Background: The leaves of Perilla frutescens, commonly called perilla and used for food in Korea, contain components with a variety of biological effects and potential therapeutic applications. The purpose of this study was to identify the components of 70% ethanol extracted Perilla frutescens (EEPF) and determine its inhibitory effects on oral microbial activity and production of nitric oxide (NO) and prostaglandin E2 (PGE2) in lipopolysaccharides (LPS)-stimulated Raw264.7 macrophages, consequently, to confirm the possibility of using EEPF as a functional component for improving the oral environment and preventing inflammation. Methods: One kg of P. frutescens leaves was extracted with 70% ethanol and dried at -70℃. EEPF was analyzed using high-performance liquid chromatography analysis, and antimicrobial activity against oral microorganisms was revealed using the disk diffusion test. Cell viability was elucidated using a methylthiazolydiphenyl-tetrazolium bromide assay, and the effect of EEPF on LPS-induced morphological variation was confirmed through microscopic observation. The effect of EEPF on LPS-induced production of pro-inflammatory mediators, NO and PGE2 was confirmed by the NO assay and PGE2 enzyme-linked immunosorbent assay. Results: The main component of EEPF was rosemarinic acid, and EEPF showed weak anti-bacterial and anti-fungal effects against microorganisms living in the oral cavity. EEPF did not show toxicity to Raw264.7 macrophages and had inhibitory effects on the morphological variations and production of pro-inflammatory mediators, NO and PGE2 in LPS-stimulated Raw264.7 macrophages. Conclusion: EEPF can be used as a functional material for improving the oral environment through the control of oral microorganisms and for modulating inflammation by inhibiting the production of inflammatory mediators.

• The Korean Journal of Pharmacology
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• v.29 no.2
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• pp.263-274
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• 1993

Potassium $(K^+)$ channels are present in airway smooth muscle cells, and their activation results in hyperpolarization and relaxation. Because these effects may have therapeutic relevance to hypersensitivity and asthma, we examined the effect of a potassium channel activator, cromakalim (BRL 34915, CK) on the release of mediators from superfused tracheal and parenchymal strips after passive sensitization with $IgG_1$ antibody. Both tissues were superfused with CK $(2{\times}10^{-6}\;M)$ for 30 min and challenged with CK and antigen (Ox-HSA). Using monodispersed, partially purified, highly purified guinea pig lung mast cells, we also examined the effect of CK on mediator release from these cells after passive sensitization with $IgG_{1}$ antibody $({\alpha}-OA)$. Guinea pig lung mast cells were purified using enzyme digestion method, count current elutriation, and discontinuous Percoll density gradient. After CK pretreatment, passively sensitized mast cells were challenged with varying concentration of antigen (OA, immunological stimuli) or with varying concentration of calcium ionophore (CaI, non-immunological stimuli). Histamine (Hist) release was determined by spectrophotofluorometry, and leukotrienes (LT) by radioimmunoassy. CK pretreatment decreased Hist by 35% and LT release by 40% in the antigen-induced tracheal tissue after $IgG_1$ sensitization but did not decrease the contractile response. In the antigen-induced parenchymal tissue CK decreased Hist release by 25% but poorly decreased LT. Both immunologic and non-immunologic stimuli caused a dose-dependent release of Hist and LT from monodispersed, partially purified and highly purified lung mast cells. Verification of LT release was obtained by the use of 5-lipoxygenase inhibitor, A64077 (Zileuton). CK decreased Hist and LT release by 20% respectively in the OA-induced guinea pig lung mast cells after $IgG_1$ sensitization. The inhibitory effects of CK on the Hist and LT release in the Ox-HSA-induced airway smooth muscle tissues or in the OA-induced and CaI-induced mast cells after $IgG_1$ sensitization were completely blocked by TEA and GBC. These studies show that guinea pig lung mast cells seem to be an important contributor to LT release, and that CK (which has been known as an airway smooth muscle relaxant) can in part act to inhibit mediator release in the antigen-induced airway smooth muscle, and that CK may also act to inhibit mediator release in the OA-induced and CaI-induced highly purified mast cells. These results suggest that Hist and LT release evoked by mast cell activation might in part be associated with $K{^+}4 channel activity.

• Journal of the Korean Society of Child Welfare
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• no.56
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• pp.133-164
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• 2016

This study investigated the effect of housing poverty in childhood on adolescents' subjective well-being. Specifically, this study examined whether the major factors that have been known to affect adolescents' well-being (i.e., family relationships, peer relationships, school adjustment etc.) mediated the relationship between housing poverty and adolescents' well-being. And then this study aimed to present an empirical evidence for establishing policies against housing poverty in order to enhance adolescent's subjective happiness. Data were derived from the $1^{st}$, $4^{th}$, and $7^{th}$ surveys of the Korea Welfare Panel Study(KOWEPS), and the sample included. 512 high school children in the $7^{th}$ survey. This study utilized structural equation modeling. Housing poverty was measured by the sub-minimum standard housing condition and the household's burden of housing expenditure. Family relationship, as a mediator, was measured by parental involvement in education, parental monitoring, and family conflicts. Another mediator, school adjustment was measured by school environment and school bonding, and the last mediator, peer relationship was measured by friend attachment and peer attachment. The results showed that housing poverty had significant negative effects on the adolescents' subjective well-being. The sub-minimum standard housing condition with inadequate size and facilities negatively affected adolescents' relationships with family directly and subjective well-being indirectly. In addition, the negative family relationships due to the sub-minimum standard housing condition negatively affected adolescents' subjective well-being through school adjustment and peer relationships. The greater the proportion of income a household spends on housing expenditure, the less likely for adolescents to report positive well-being. The sub-minimum standard housing condition had indirect effects through family relationships, whereas the household's housing expenditure directly affected adolescents' subjective well-being. This study suggested the necessity of interventions to alleviate housing poverty for adolescents' families and lays the groundwork for housing poverty policies in Korea.

• Journal of Korea Soil Environment Society
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• v.5 no.2
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• pp.87-97
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• 2000

The effects of environmental conditions, initial dissolved oxygen concentrations, pH, and the presence of electron carrier vitamin $B_{12}$, on the reduction rate of Tn by $Fe^0$ was quantitatively analyzed using a batch reactor In all experiments, TNT reduction was best described with a first order reaction and the reduction rate decreased with the increase in the initial DO concentration. However, the specific reaction rate did not decrease linearly with the increase in the initial DO concentration. In the presence of HEPES buffer 0.2 and 2.0 mM(pH 5.7$\pm$0.2), the specific reaction rate increased more than 5.8 times, which showed reduction rate is rather significantly influenced by the pH of the solution. To test the possibility of reaction rate enhancement, well-known electron carrier(or mediator) , vitamin $B_{12}$, has augmented besides $Fe^0$. In the presence of 8.0 $mu\textrm{g}$/L of vitamin $B_{12}$, the specific reaction rate increased as much as 14.6 times. The results indicate that the addition of trace amount of vitamin $B_{12}$ can be a promising rate controlling option for the removal of organics using a $Fe^0$ filled permeable reactive barrier.

• The Journal of the Korea Contents Association
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• v.18 no.2
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• pp.592-601
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• 2018

The purpose of this study is to investigate the relationship among empathy ability, gratitude tendency, helping behavior, and happiness of college students and whether gratitude tendency and help behaviors are mediators in the relationship between empathy ability and happiness. For this purpose, Date were collected from 559 college students in S and K city. The SPSS 20.0 program was used to analyze the statistical data such as the mean and standard deviation of the data. To analyze the validity of the study, it conducted confirmatory factor analysis using AMOS. Finally, we analyzed the effect of empathy on happiness by using the bootstrap procedure in order to investigate the mediating effects of gratitude tendency and helping behavior. The results of the study are as follows. First, the correlation of each was positive. Second, in the relationship between empathy ability and happiness, the gratitude tendency was a statistically significant mediator. Third, helping behavior was a statistically significant mediator between empathy and happiness. Fourth, in the relationship between empathy ability and happiness, it did not do dual mediate to the gratitude tendency and help behavior. The implications and limitations of this study are discussed.