• Journal of Environmental Health Sciences
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• v.49 no.2
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• pp.89-98
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• 2023

Background: Organophosphorus flame retardants (OPFRs) are a group of chemical substances used in building materials and plastic products to suppress or mitigate the combustion of materials. Although OPFRs are generally used in mixed form, information on their mixture toxicity is quite scarce. Objectives: This study aims to elucidate the toxicity and determine the types of interaction (e.g., synergistic, additive, and antagonistic effect) of OPFRs mixtures. Methods: Nine organophosphorus flame retardants, including TEHP (tris(2-ethylhexyl) phosphate) and TDCPP (tris(1,3-dichloro-2-propyl) phosphate), were selected based on indoor dust measurement data in South Korea. Nine OPFRs were exposed to the luminescent bacteria Aliivibrio fischeri for 30 minutes and the human hepatocyte cell line HepG2 for 48 hours. Chemicals with significant toxicity were only used for mixture toxicity tests in HepG2. In addition, the observed EC_x values were compared with the predicted toxicity values in the CA (concentration addition) prediction model, and the MDR (model deviation ratio) was calculated to determine the type of interaction. Results: Only four chemicals showed significant toxicity in the luminescent bacteria assays. However, EC₅₀ values were derived for seven out of nine OPFRs in the HepG2 assays. In the HepG2 assays, the highest to lowest EC₅₀ were in the order of the molecular weight of the target chemicals. In the further mixture tests, most binary mixtures show additive interactions except for the two combinations that have TPhP (triphenyl phosphate), i.e., TPhP and TDCPP, and TPhP and TBOEP (tris(2-butoxyethyl) phosphate). Conclusions: Our data shows OPFR mixtures usually have additivity; however, more research is needed to find out the reason for the synergistic effect of TPhP. Also, the mixture experimental dataset can be used as a training and validation set for developing the mixture toxicity prediction model as a further step.

• Journal of Life Science
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• v.32 no.3
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• pp.241-248
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• 2022

NF-κB acts as a critical transcription factor in inflammation and innate immunity, and it is also closely involved in cell survival and tumorigenesis via induction of anti-apoptotic genes. In these processes, NF-κB cooperates with multiple other signaling molecules and pathways, and although many studies have demonstrated that Hsp90 regulates NF-κB activity, the exact mechanism is unclear. In this study, we investigated the relationship between Hsp90 and IKKγ in the regulation of NF-κB using expression plasmids of IKK complex components. Wild-type and deletion mutants of IKKγ were expressed together with Hsp90, and the combined regulatory effect of Hsp90 and IKKγ on NF-κB activation was assayed. The results show that Hsp90 activates NF-κB by promoting the phosphorylation and degradation of IκBα and that activation of NF-κB by NIK and LPS was increased by Hsp90. IKKγ elevated the effect of Hsp90 on NF-κB activation by increasing phosphorylation and degradation of IκBα. The positive regulation on NF-κB by Hsp90 and IKKγ was also proved in analysis with IKKβ-EE, the constitutively active form of IKKβ. In experiments with the deletion mutants of IKKγ, the N-terminal IKKβ binding domain, C-terminal leucine zipper, and zinc finger domains of IKKγ were found not necessary for the positive regulation of NF-κB activity. Additionally, the expression of pro-inflammatory cytokines was synergistically elevated by Hsp90 and IKKγ. These results indicate that inhibiting the interaction between Hsp90 and IKKγ is a possible strategic method for controlling NF-κB and related diseases.

• Journal of Veterinary Science
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• v.23 no.1
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• pp.8.1-8.15
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• 2022

Background: Brucella infection induces brucellosis, a zoonotic disease. The intracellular circulation process and virulence of Brucella mainly depend on its type IV secretion system (T4SS) expressing secretory effectors. Secreted protein BspJ is a nucleomodulin of Brucella that invades the host cell nucleus. BspJ mediates host energy synthesis and apoptosis through interaction with proteins. However, the mechanism of BspJ as it affects the intracellular survival of Brucella remains to be clarified. Objectives: To verify the functions of nucleomodulin BspJ in Brucella's intracellular infection cycles. Methods: Constructed Brucella abortus BspJ gene deletion strain (B. abortus ∆BspJ) and complement strain (B. abortus pBspJ) and studied their roles in the proliferation of Brucella both in vivo and in vitro. Results: BspJ gene deletion reduced the survival and intracellular proliferation of Brucella at the replicating Brucella-containing vacuoles (rBCV) stage. Compared with the parent strain, the colonization ability of the bacteria in mice was significantly reduced, causing less inflammatory infiltration and pathological damage. We also found that the knockout of BspJ altered the secretion of cytokines (interleukin [IL]-6, IL-1β, IL-10, tumor necrosis factor-α, interferon-γ) in host cells and in mice to affect the intracellular survival of Brucella. Conclusions: BspJ is extremely important for the circulatory proliferation of Brucella in the host, and it may be involved in a previously unknown mechanism of Brucella's intracellular survival.

• Journal of Korean Medicine for Obesity Research
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• v.23 no.1
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• pp.1-9
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• 2023

Objectives: Noni fruit juice (NFJ) is liquor extracted from Morinda citrifolia (noni) fruit and has been used as an herbal remedy in many countries. However, the NFJ's anti-adipogenic and anti-inflammatory effects on adipocytes are poorly understood. The purpose of this study was to explore the commercially standardized NFJ effects on lipid accumulation throughout 3T3-L1 preadipocytes differentiation and interleukin-1β (IL-1β)-mediated inducible nitric oxide synthase (iNOS) expression in 3T3-L1 preadipocytes. Methods: Cellular lipid accumulation and triglyceride (TG) content in differentiating 3T3-L1 preadipocytes were assessed subsequently via the Oil Red O staining and AdipoRed assay. MTS assay was used to examine NFJ cytotoxicity in (differentiating) 3T3-L1 preadipocytes. Immunoblotting and reverse transcriptase polymerase chain reaction analysis were used to measure the expression levels of target protein and mRNA in (differentiating) 3T3-L1 preadipocytes, respectively. Results: NFJ treatment at 150 μL/mL led to a substantial reduction of fat accumulation and TG content during 3T3-L1 adipogenesis with no discernable impact on the cell viability. Of note, while NFJ treatment (150 μL/mL) largely inhibited the CCAAT/enhancer-binding protein-α (C/EBP-α) and peroxisome proliferator-activated receptor-β (PPAR-β) protein expressions, it did not influence PPAR-γ in differentiating 3T3-L1 preadipocytes. Of interest, treatment with IL-1β at 20 ng/mL for 4 hours elicited in firm induction of iNOS mRNA expression in 3T3-L1 preadipocytes. However, NFJ treatment at 100 or 200 μL/mL greatly attenuated the IL-1β-induced iNOS mRNA expression in 3T3-L1 preadipocytes. Conclusions: NFJ has anti-adipogenic and anti-inflammatory effects on (differentiating) 3T3-L1 preadipocytes which are in part intervened via control of the expression of C/EBP-α, PPAR-β, and iNOS.

• Journal of Korean Medicine Rehabilitation
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• v.33 no.3
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• pp.47-65
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• 2023

Objectives We evaluated the wound healing effects of Dangguijakyak-san (DJ) using C57BL/6 mice that were generated open wound. Methods The study was conducted with seven C57BL/6 mice assigned to each group, divided into the normal group, control group, vitamin E group, DJ low-dose group, DJ high-dose group. We measured total polyphenol, flavonoid contents, the size of the wound, liver function, pro-inflammatory cytokine activity in serum, inflammation-related proteins, adhesion molecules and chemokine proteins, collagen-related proteins in skin tissue and histopathological changes by H&E and Masson's staining. Results DJ treatment significantly reduced the area of the wound compared to the control group. Also, inflammatory cytokines were reduced and the expression of anti-inflammatory-related factors (interleukin-4 [IL-4] and IL-10) was significantly increased in the DJ treatment group. We identified that DJ treatment inhibits both pathways of inflammation, the mitogen-activated protein kinases and nuclear factor-κB pathway. Moreover, the protein expressions of Sirt1 (sirtuin 1), MCP-1 (monocyte chemoattractant protein 1), ICAM-1 (intercellular adhesion molecule 1), and VCAM-1 (vascular cell adhesion molecule 1) were decreased by DJ administration. Also, the expression of α-smooth muscle actin and collagen type I alpha 1, collagen-related proteins, that help skin recovery was significantly increased in the DJ treatment group. Histopathologically, a relatively thin epithelial layer could be observed in the DJ administration group, as well as an increase in fibroblasts and collagen fibers. Conclusions These data suggest that DJ treatment is effective in wound healing, suppressing inflammatory proteins, increasing skin repair factors and improving histopathological changes caused by wounds.

• Asia Marketing Journal
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• v.14 no.3
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• pp.27-48
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• 2012

Temperature and weather are all around us, quite literally. Furthermore, temperature and weather not only permeate our atmosphere, constantly affecting our visceral states of warmth and coldness, but they metaphorically permeate our language. People, products, and ideas can all be "hot" or "cold." Given this ubiquity, it is perhaps surprising that relatively little research has systematically examined the influence of temperature on choice and judgment. Temperature-related words such as "hot" and "cold" are often used to describe impulsive and calculated behaviors, respectively. These metaphoric connotations of thermal concepts raise the question as to whether temperature, psychological states and decision making are related to each other, and if so, how. The current research examines these questions and finds support for a relationship. Across one field study and one laboratory experiment, I demonstrate that both hot ambient room temperature (Spa) and hot temperature primes (words) trigger decision outcomes in line with the metaphoric association between hot temperature and impulsivity. In the field study, participants were recruited in hot (40-50 degrees Celsius) and cold (10 degrees Celsius) rooms at a spa. Participants were simply asked to indicate their willingness-to-pay (WTP) for three product categories (travel package, birthday dinner, and cell phone). The results showed that participants in the hot room in comparison to those in the cold room were willing to pay more for the same products. Next, I tested if our results would go beyond ambient temperature and would hold if I were to prime temperature concepts by using a different priming method (i.e., subliminal vs. supraliminal). In line with the previous findings in the spa, participants in the hot priming condition were more likely to choose the wrong answer for the bat and baseball question than those in the cold priming condition. In addition, product type (e.g., pleasure vs. necessity) can moderate the effect of hot temperature on impulsivity. Mood and arousal did not mediate participants' responses. My findings seem to suggest that the effects of temperature on decision outcomes can be attributed to metaphoric associations rather than incidental mood or arousal. The current research applies a novel perspective in understanding the relationship between temperature and judgment and decision making. Also, the results have practical implications for packaging, advertising, merchandising, and pricing of goods and services, as well as for public policy and awareness. One of the most natural implications of my findings would be that retailers would be better off carrying more impulse purchase items on hot days. Furthermore, point-of-purchase promotions encouraging impulse purchase is more likely to be effective in retail environments with higher temperature than with lower temperature. In addition, advertisements and product packages evoking hot temperature associations (e.g., beach, sunshine, summer) might lead consumers to pay higher price for the advertised product than those with cold temperature associations.

• Applied Chemistry for Engineering
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• v.34 no.5
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• pp.534-540
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• 2023

The high-rate performance is limited by several factors, such as polarization generation, low electrical conductivity, low surface energy, and low electrolyte permeability of CF_X, which is widely used as a cathode active material in the lithium primary battery. Therefore, in this study, we aimed to improve the battery performance by using carbon fluoride modified by surface treatment using oxygen plasma as a cathode for lithium primary batteries. Through XPS and XRD analysis, changes in the surface chemical characteristics and crystal structure of CF_X modified by oxygen plasma treatment were analyzed, and accordingly, the electrochemical characteristics of lithium-ion primary batteries were analyzed and discussed. As a result, the highest number of semi-ionic C-F bonds were formed under the oxygen plasma treatment condition (7.5 minutes) with the lowest fluorine to carbon (F/C) ratio. In addition, the primary cell prepared under this condition using carbon fluoride as the active material of the cathode showed the highest 3 F/C(3 C rate-performance) rate-performance and maintained a relatively high capacity (550 mAh/g) even at high rates. In this study, it was possible to produce lithium primary batteries with high-rate performance by adjusting the fluorine contents of carbon fluoride and the type of carbon-fluorine bonding through oxygen plasma treatment.

• Journal of Life Science
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• v.34 no.6
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• pp.426-433
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• 2024

The environmental stress that plants are most susceptible to is water stress. Abscisic acid (ABA) is a plant hormone synthesized by plants to counteract environmental stress. The role of stomata in plants is to allow the synthesis of sucrose by absorbing CO₂, which greatly affects photosynthetic activity. In addition, stomata are pathways for transpiration, which releases H₂O and help establish a water potential gradient that allows plant roots to continuously absorb water and inorganic substances from the soil. Plants have a mechanism to minimize water loss by closing their stomata when exposed to water-stressed environments. The most well-studied hypothesis concerning the mechanism of stomatal closure is the response to water stress. When a plant receives sufficient water, its stomata open during the day and close at night due to its circadian rhythm. In addition, stomatal closure occurs when the concentration of CO₂ in the intercellular space increases. However, the mechanism of stomatal closure due to circadian rhythm and increased CO₂ concentration in the intercellular space is not well understood. When plants undergo water stress, the increased concentration of ABA in the guard cell cytoplasm induces an increase in Ca²⁺ concentration, resulting in cytoplasmic depolarization. As a result, the outward K⁺-channel of the tonoplast and the slow-type anion channels SLAC1 and SLAH3 are activated, releasing K⁺, Cl^-, and malate^2-, causing the stomata to close. Therefore, in this paper, the mechanism of stomatal closure caused by water stress was investigated.

• IMMUNE NETWORK
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• v.22 no.5
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• pp.40.1-40.24
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• 2022

Mesenchymal stem cells (MSCs) are attractive alternatives to conventional anti-asthmatic drugs for severe asthma. Mechanisms underlying the anti-asthmatic effects of MSCs have not yet been elucidated. This study evaluated the anti-asthmatic effects of intravenously administered MSCs, focusing on macrophages and monocytes. Seven-week-old transgenic (Tg) mice with lung-specific overexpression of IL-13 were used to simulate chronic asthma. MSCs were intravenously administered four days before sampling. We examined changes in immune cell subpopulations, gene expression, and histological phenotypes. IL-13 Tg mice exhibited diverse features of chronic asthma, including severe type 2 inflammation, airway fibrosis, and mucus metaplasia. Intravenous administration of MSCs attenuated these asthmatic features just four days after a single treatment. MSC treatment significantly reduced SiglecF^-CD11c^-CD11b⁺ monocyte-derived macrophages (MoMs) and inhibited the polarization of MoMs into M2 macrophages, especially M2a and M2c. Furthermore, MSCs downregulated the excessive accumulation of Ly6c^- monocytes in the lungs. While an intravenous adoptive transfer of Ly6c^- monocytes promoted the infiltration of MoM and Th2 inflammation, that of MSC-exposed Ly6c^- monocytes did not. Ex vivo Ly6c^- MoMs upregulated M2-related genes, which were reduced by MSC treatment. Molecules secreted by Ly6c^- MoMs from IL-13 Tg mice lungs upregulated the expression of fibrosis-related genes in fibroblasts, which were also suppressed by MSC treatment. In conclusion, intravenously administered MSCs attenuate asthma phenotypes of chronic asthma by modulating macrophages. Identifying M2 macrophage subtypes revealed that exposure to MSCs transforms the phenotype and function of macrophages. We suggest that Ly6c^- monocytes could be a therapeutic target for asthma management.

• IMMUNE NETWORK
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• v.22 no.2
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• pp.16.1-16.20
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• 2022

The gastrointestinal tract is the first organ directly affected by fasting. However, little is known about how fasting influences the intestinal immune system. Intestinal dendritic cells (DCs) capture antigens, migrate to secondary lymphoid organs, and provoke adaptive immune responses. We evaluated the changes of intestinal DCs in mice with short-term fasting and their effects on protective immunity against Listeria monocytogenes (LM). Fasting induced an increased number of CD103⁺CD11b^- DCs in both small intestinal lamina propria (SILP) and mesenteric lymph nodes (mLN). The SILP CD103⁺CD11b^- DCs showed proliferation and migration, coincident with increased levels of GM-CSF and C-C chemokine receptor type 7, respectively. At 24 h post-infection with LM, there was a significant reduction in the bacterial burden in the spleen, liver, and mLN of the short-term-fasted mice compared to those fed ad libitum. Also, short-term-fasted mice showed increased survival after LM infection compared with ad libitum-fed mice. It could be that significantly high TGF-β2 and Aldh1a2 expression in CD103⁺CD11b^- DCs in mice infected with LM might affect to increase of Foxp3⁺ regulatory T cells. Changes of major subset of DCs from CD103⁺ to CD103^- may induce the increase of IFN-γ-producing cells with forming Th1-biased environment. Therefore, the short-term fasting affects protection against LM infection by changing major subset of intestinal DCs from tolerogenic to Th1 immunogenic.