• Title/Summary/Keyword: modifier

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Preparation of MA-PLA Using Radical Initiator and Miscibility Improvement of PLA/PA11 Blends (라디칼 개시제를 이용한 MA-PLA 제조 및 바이오플라스틱 PLA/PA11 블렌드의 상용성 개선)

  • Lee, Jong-Eun;Kim, Han-Eol;Nam, Byeong-Uk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.4
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    • pp.76-85
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    • 2019
  • Recently, various investigation of vegetable oil which is extracted from natural resources is being progressed because of its low cost and environmental aspect. However, double bonds in vegetable oil should be substituted to other high reactive functional group due to its low reactivity for synthesizing bio-polymeric materials. ${\alpha}$-eleostearic acid, which is consist of conjugated triene, is the main component of tung oil, and the conjugated triene allows tung oil to have higher reactivity than other vegetable oil. In this study, tung oil is copolymerized with styrene and divinylbenzene to make thermoset resin without any substitution of functional group. Thermal and mechanical properties are measured to investigate the effects of the composition of each monomer on the synthesized thermoset resin. The result shows that the products have only one Tg, which means the synthesized thermoset resins are homogeneous in molecular level. Mechanical properties show that tung oil act as soft segment in the copolymer and make more elastic product. On the other hand, divinylbenzene acts as hard segment and makes more brittle product.

Zearalenone regulates key factors of the Kelch-like erythroid cell-derived protein with CNC homology-associated protein 1-nuclear factor erythroid 2-related factor 2 signaling pathway in duodenum of post-weaning gilts

  • Cheng, Qun;Jiang, Shu zhen;Huang, Li bo;Yang, Wei ren;Yang, Zai bin
    • Animal Bioscience
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    • v.34 no.8
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    • pp.1403-1414
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    • 2021
  • Objective: This study explored the mechanism of the Kelch-like erythroid cell-derived protein with CNC homology-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway under conditions of zearalenone (ZEA)-induced oxidative stress in the duodenum of post-weaning gilts. Methods: Forty post-weaning gilts were randomly allocated to four groups and fed diets supplemented with 0, 0.5, 1.0, or 1.5 mg/kg ZEA. Results: The results showed significant reductions in the activity of the antioxidant enzymes total superoxide dismutase and glutathione peroxidase and increases the malondialdehyde content with increasing concentrations of dietary ZEA. Immunohistochemical analysis supported these findings by showing a significantly increased expression of Nrf2 and glutathione peroxidase 1 (GPX1) with increasing concentrations of ZEA. The relative mRNA and protein expression of Nrf2, GPX1 increased linearly (p<0.05) and quadratically (p<0.05), which was consistent with the immunohistochemical results. The relative mRNA expression of Keap1 decreased linearly (p<0.05) and quadratically (p<0.05) in the duodenum as the ZEA concentration increased in the diet. The relative mRNA expression of modifier subunit of glutamate-cysteine ligase (GCLM) increased quadratically (p<0.05) in all ZEA treatment groups and the relative mRNA expression of quinone oxidoreductase 1 (NQO1) catalytic subunit of glutamate-cysteine ligase decreased linearly (p<0.05) and quadratically (p<0.05) in the ZEA1.0 group and ZEA1.5 group. The relative protein expression of Keap1 and GCLM decreased quadratically (p<0.05) in the duodenum as the ZEA concentration increased in the diet, respectively. The relative protein expression of NQO1 increased linearly (p<0.05) and quadratically (p<0.05) in all ZEA treatment groups in the duodenum. Conclusion: These findings suggest that ZEA regulates the expression of key factors of the Keap1-Nrf2 signaling pathway in the duodenum, which enables resistance to ZEA-induced oxidative stress. Further studies are needed to examine the effects of ZEA induced oxidative stress on other tissues and organs in post-weaning gilts.

Expression of Antimicrobial Peptide (AMP), Moricin Using SUMO Fusion Tag in Escherichia coli (대장균에서 SUMO fusion tag을 이용하여 항균펩타이드인 moricin의 발현)

  • Ahn, Dong-gyu;Park, Sun Ill;Kim, Soon Young
    • Journal of Life Science
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    • v.32 no.12
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    • pp.956-961
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    • 2022
  • Plant Chloroplast have several advantages as an expression platform of biopharmaceuticals over conventional expression platforms such as mammalian cells, yeast and bacteria. First, plants do not serve as a host for mammalian infectious virus and have endotoxin like bacteria which can cause anaphylactic shock. In addition, high copy number of chloroplast genome allows for chloroplast transformants to reach the high level of expression of heterologous genes. Moreover, the integration of transgenes into specific region of chloroplast genomes makes chloroplast transformants unaffected by positional effect which can be frequently observed from nuclear transformants, resulting in loss of transgene expressions. Antimicrobial peptides (AMPs) are a kind of innate immunity which is found from bacteria to humans. Unlike conventional antibiotics, very less dosage of AMPs can have catastrophic effect on bacterial survival. Further, the repeated use of AMPs does not trigger the development of bacterial resistance. Moricin, one of the AMPs, was isolated from Bombyx mori, a silkworm moth. The C-terminal of moricin consists largely of basic amino acids, and the N-terminal has an α-helix structure. Moricin was chosen and expressed in a SUMO/SUMOase without leaving any unwanted amino acids which could potentially affect the anti-bacterial activity of the moricin. The transformation vector used in this study has already been created in this lab for the expression in both prokaryotic systems such as E. coli and chloroplast. The expressed moricin was purified using Ni columns and SUMOase, and the antibacterial activity of the purified moricin was confirmed using an agar diffusion assay.

Ginsenoside F1 attenuates pirarubicin-induced cardiotoxicity by modulating Nrf2 and AKT/Bcl-2 signaling pathways

  • Yang Zhang;Jiulong Ma;Shan Liu;Chen Chen;Qi Li;Meng Qin;Liqun Ren
    • Journal of Ginseng Research
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    • v.47 no.1
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    • pp.106-116
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    • 2023
  • Background: Pirarubicin (THP) is an anthracycline antibiotic used to treat various malignancies in humans. The clinical usefulness of THP is unfortunately limited by its dose-related cardiotoxicity. Ginsenoside F1 (GF1) is a metabolite formed when the ginsenosides Re and Rg1 are hydrolyzed. However, the protective effects and underlying mechanisms of GF1 on THP-induced cardiotoxicity remain unclear. Methods: We investigated the anti-apoptotic and anti-oxidative stress effects of GF1 on an in vitro model, using H9c2 cells stimulated by THP, plus trigonelline or AKT inhibitor imidazoquinoxaline (IMQ), as well as an in vivo model using THP-induced cardiotoxicity in rats. Using an enzyme-linked immunosorbent test, the levels of malondialdehyde (MDA), brain natriuretic peptide (BNP), creatine kinase (CK-MB), cardiac troponin (c-TnT), lactate dehydrogenase (LDH), superoxide dismutase (SOD) and glutathione (GSH) were determined. Nuclear factor (erythroid-derived2)-like 2 (Nrf2) and the expression of Nrf2 target genes, including heme oxygenase-1 (HO-1), glutathione-S-transferase (Gst), glutamate-cysteine ligase modifier subunit (GCLM), and expression levels of AKT/Bcl-2 signaling pathway proteins were detected using Western blot analysis. Results: THP-induced myocardial histopathological damage, electrocardiogram (ECG) abnormalities, and cardiac dysfunction were reduced in vivo by GF1. GF1 also decreased MDA, BNP, CK-MB, c-TnT, and LDH levels in the serum, while raising SOD and GSH levels. GF1 boosted Nrf2 nuclear translocation and Nrf2 target gene expression, including HO-1, Gst, and GCLM. Furthermore, GF1 regulated apoptosis by activating AKT/Bcl-2 signaling pathways. Employing Nrf2 inhibitor trigonelline and AKT inhibitor IMQ revealed that GF1 lacked antioxidant and anti-apoptotic effects. Conclusion: In conclusion, GF1 was found to alleviate THP-induced cardiotoxicity via modulating Nrf2 and AKT/Bcl-2 signaling pathways, ultimately alleviating myocardial oxidative stress and apoptosis.

Association between physical activity and periodontitis as stratified by obesity in Koreans (한국인에서 비만에 따른 신체활동와 치주질환과의 연관성)

  • Mi-Sun Kim;Hye-Sun Shin
    • Journal of Korean Dental Hygiene Science
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    • v.6 no.1
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    • pp.65-76
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    • 2023
  • Background: The aim of this study was to examine the association between physical activity and periodontitis in the Korean population. Methods: This study utilized data from 9,191 participants of the Korea National Health and Nutrition Examination Survey. Periodontitis was defined as a CPI score of 3 or 4. Physical activity was assessed by the trained interviewer using the International Physical Activity Questionnaire-Short Form (IPAQ-SF). IPAQ-SF is composed of vigorous physical activity, moderate physical activity, and walking activity. Multivariable logistic regression analyses and stratified analyses by obesity were performed. All analyses were conducted separately for males and females. Results: Females who engaged in vigorous and moderate physical activity had a 28% (OR = 0.72, 95% CI = 0.54 - 0.95) and 34% (OR = 0.66, 95% CI = 0.44 - 0.98) lower risk of periodontitis, respectively. In obese females, moderate physical activity in obese had a 65% lower risk of periodontitis (OR = 0.35, 95% CI = 0.18 - 0.67). Conclusions: Our findings suggest that moderate-intensity physical activity was inversely associated with a lower risk of periodontitis. In obese females, moderate physical activity had an independent inverse association with periodontitis.

High-purity Lithium Carbonate Manufacturing Technology from the Secondary Battery Recycling Waste using D2EHPA + TBP Solvent (이차전지 폐액으로부터 D2EHPA + TBP solvent를 활용한 탄산리튬 제조기술)

  • Dipak Sen;Hee-Yul Yang;Se-Chul Hong
    • Resources Recycling
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    • v.32 no.1
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    • pp.21-32
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    • 2023
  • Because the application of lithium has gradually increased for the production of lithium ion batteries (LIBs), more research studies about recycling using solvent extraction (SX) should focus on Li+ recovery from the waste solution obtained after the removal of the valuable metals nickel, cobalt and manganese (NCM). The raffinate obtained after the removal of NCM metal contains lithium ions and other impurities such as Na ions. In this study, we optimized a selective SX system using di-(2-ethylhexyl) phosphoric acid (D2EHPA) as the extractant and tri-n-butyl phosphate (TBP) as a modifier in kerosene for the recovery of lithium from a waste solution containing lithium and a high concentration of sodium (Li+ = 0.5 ~ 1 wt%, Na+ = 3 ~6.5 wt%). The extraction of lithium was tested in different solvent compositions and the most effective extraction occurred in the solution composed of 20% D2EHPA + 20% TBP + and 60% kerosene. In this SX system with added NaOH for saponification, more than 95% lithium was selectively extracted in four extraction steps using an organic to aqueous ratio of 5:1 and an equilibrium pH of 4 ~ 4.5. Additionally, most of the Na+ (92% by weight) remained in the raffinate. The extracted lithium is stripped using 8 wt% HCl to yield pure lithium chloride with negligible Na content. The lithium chloride is subsequently treated with high purity ammonium bicarbonate to afford lithium carbonate powder. Finally the lithium carbonate is washed with an adequate amount of water to remove trace amounts of sodium resulting in highly pure lithium carbonate powder (purity > 99.2%).

Effect of Mechanical and Toughening Characteristics of Epoxy/Carbon Fiber Composite by Polyamide 6 Particles, CTBN Addition Technology (Polyamide 6 입자 및 CTBN 첨가 기술에 따른 에폭시/탄소섬유 복합재의 강인화 효과 및 기계적 특성)

  • Sung-Youl Bae;Kyo-Moon Lee;Sanjay Kumar;Ji-Hun Seok;Jae-Wan Choi;Woo-Hyuk Son;Yun-Hae Kim
    • Composites Research
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    • v.36 no.5
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    • pp.355-360
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    • 2023
  • Epoxy-based carbon fibers reinforced plastic (CFRP) exhibit limitations in their suitability for industrial applications due to high brittleness characteristics. To address this challenge, extensive investigations are underway to enhance their toughness properties. This research focuses on evaluating the toughening mechanisms achieved by Polyamide 6 particles(p-PA6) and Carboxyl-Terminated Butadiene-Acrylonitrile (CTBN) elastomer, with a specific emphasis on utilizing minimal additive quantities. The study explores the impact of varying concentrations of p-PA6 and CTBN additives, namely 0.5, 1, 2.5, and 5 phr, through comprehensive Mode I fracture toughness and tensile strength analyses. The inclusion of p-PA6 demonstrated improvements in toughness when introduced at a relatively low content of 1phr. This improvement manifested as a sustained fracture behavior, contributing to enhanced toughness, while simultaneously maintaining the material's tensile strength. Furthermore, the investigation revealed that the incorporation of p-PA6 affected in particle aggregation, thus influencing the overall toughening mechanism. Incorporation of CTBN, an elastomeric modifier, exhibited a pronounced increase in fracture toughness at higher concentrations of 2.5 phr and beyond. However, this increase in toughness was accompanied by a reduction in tensile strength, resulting in fracture behavior similar to conventional CFRP exhibiting brittleness. The synergy between pPA6, CTBN and CFRP appeared to marginally enhance tensile strength under specific content conditions. As a result of this study, optimized conditions for the application of the p-PA6, CTBN toughening technology have been identified and established.

Compilation of 104 Experimental Theses on the Antitumor and Immuno-activating therapies of Oriental Medicine (한의학의 항종양 면역치료에 관한 연구 -1990년 이후 발표된 실험논문을 중심으로-)

  • Kang Yeon Yee;Kim Tai Im;Park Jong Ho;Kim Sung Hoon;Park Jong Dai;Kim Dong Hee
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.1
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    • pp.1-24
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    • 2003
  • This study was done to compile 104 experimental theses which are related to the antitumor and immuno-activating therapies between February 1990 through February 2002. Master's and doctoral theses were dassified by schools, degrees, materials, effects, experimental methods of antitumor and immunoactivity, and results. The following results were obtained from this study : 1. Classifying the theses by the school, 34.6% were presented by Daejeon University, 29.8% by Kyung-hee University and 11.5% by Won-kwang University. Of all theses, 51.0% were aimed for the doctoral degree and 43.3% were for the master's degree. All of three universities have their own cancer centers. 2. Classifying the theses by herb materials, complex prescription accounted for 60.3%, single herb accounted for 24.8% and herbal acupuncture accounted for 14.2%. Considering the key principles of the traditional medicine, complex prescription was much more thoroughly studied than single herb prescription. The results showed that the complex prescription had both antitumor activity and immuno-activating activity, which might reflects on multi-activation mechanisms by complex components. 3. Classifying the theses by the efficacy of herbs examined, in single herb, invigorating spleen and supplementing was 35.5%, expelling toxin and cooling was 29.0%, activating blood flow and removing blood stasis was 12.9%. In herbal acupuncture, invigorating spleen and supplementing was 52.9%, expelling toxin and cooling was 29.4%. In complex prescription, pathogen-free status was 41.9%, strengthening healthy qi to eliminate pathogen was 35.5%, strengthening healthy qi was 22.6%. It is presumed that the antitumor and immunoactivating therapy based on syndrome differentiation is the best way to develop oriental oncology. 4. Classifying the theses by antitumor experiments, cytotoxic effect was 48.1 %, survival time was 48.1 % and change of tumor size was 42.3%. Survival rate was not necessarily correlated with cytotoxicity. These data reflect the characteristic, wholistic nature of the oriental medicine which is based on BRM (biological response modifier). 5. Classifying the theses by immunoactivating experiments, hemolysin titer was 51.0%, hemagglutinin titer was 46.2% and NK cell's activity was 44.2%. In the future studies, an effort to elucidate specific molecular and cellular mechanisms of cytokine production in the body would be crucial. 6. Classifying the theses according to the data in terms of antitumor activity, 50% was evaluated good, 24.0% was excellent, and 15.5% have no effect. In an evaluation of immuno-activating activity, 35.9% was excellent and 18.0% showed a little effect. The index point, as described here, may helps to use experimental data for clinical trials. Changes in index points by varying dosage implicate the importance of oriental medical theory for prescription. 7. In 167 materials, IIP (immunoactivating index point, mean : 3.12±0.07) was significantly higher than AIP(antitumor index point, mean : 2.83±0.07). These data demonstrate that the effect of herb medicine on tumor activity depends more on immunoactivating activity than antitumor activity. This further implies that the development of herbal antitumor drugs must be preceded by the mechanistic understanding of immunoactivating effect. 8. After medline-searching tumor and herb-related articles from NCBI web site, we conclude that most of the studies are primarily focused on biomolecular mechanisms and/or pathways. Henceforth, we need to define the biomolecular mechanisms and/or pathways affected by herbs or complicated prescriptions. 9. Therefore, the most important point of oriental medical oncology is to conned between experimental results and clinical trials. For the public application of herbal therapy to cancer, it is critical to present the data to mass media. 10. To develop the relationship of experimental results and clinical trials, university's cancer clinic must have a long-range plan related to the university laboratories and, at the same time, a regular consortium for this relationship is imperative. 11. After all these efforts, a new type herbal medicine for cancer therapy which is to take care of the long-term administering and safety problem must be developed. Then, it would be expected that anti-tumor herbal acupuncture can improve clinical symptoms and quality of life (QOL) for cancer patients. 12. Finally, oriental medical cancer center must be constructed in NCC (National Cancer Center) or government agency for the development of oriental medical oncology which has international competitive power.

In Vivo Immunological Activity in Fermentation with Black Rice Bran (유색미 미강발효물의 면역활성 효과)

  • Kim, Dong-Ju;Ryu, Su-Noh;Han, Sang-Jun;Kim, Hwa-Young;Kim, Jung-Hak;Hong, Seong-Gil
    • The Korean Journal of Food And Nutrition
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    • v.24 no.3
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    • pp.273-281
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    • 2011
  • Rice bran is byproducts of the hulling of rice, an important food resource in Korea. Various studies have been reported immune-enhancing effects of rice bran cultured with Lentinus edodes. In particular black rice bran contains anthocyanin, and the effects of antioxidant have been reported. The objective of the this study was to investigate the possible immune-enhancing effects of black rice bran substance extracted from a submerged culture of Lentinus edodes with black rice bran (crude fermentation-polysaccharide, CFP) and products(crude fermentation-polysaccharide-S. cerevisiae CFP-S, crude fermentation-polysaccharide-L. gasseri, CFP-L) which are of secondary fermentation of by using Saccharomyces cerevisiae and Lactobacillus gasseri in the Blab/c male mice. We found that supplementation of CFP, CFP-S and CFP-L enhanced macrophage and splenocyte proliferation compared to the control group(NC) in mice. Also, we measured the concentration of cytokines(IFN-${\gamma}$, TNF-${\alpha}$, IL-6) secreted by activated macrophage and splenocyte. The results of the experiment are that supplementation of CFP and CFP-S increased the macrophage and splenocyte proliferation compared to the control group but supplementation of CFP-L decreased the splenoyte proliferation compared to the control group(without mitogen and treated with LPS). When macrophage and splenocyte were stimulated by CFP and CFP-S supplementation, it was increased IFN-${\gamma}$, TNF-${\alpha}$ and IL-6 concentration compared with the control group. These results suggest that the capacity of CFP and CFP-S seem to act as a potent immune modulator causing augmentation of immune cell activity, and enhance the immue function through regulating cytokine production capacity by activated macrophage and splenocyte in mice.

Association between MIR149 SNPs and Intrafamilial Phenotypic Variations of Charcot-Marie-Tooth Disease Type 1A (샤르코-마리-투스병 1A형(CMT1A)의 가족내 표현형적 이질성과 MIR149 SNP에 대한 연관성 연구)

  • Choi, Yu Jin;Lee, Ah Jin;Nam, Soo Hyun;Choi, Byung-Ok;Chung, Ki Wha
    • Journal of Life Science
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    • v.29 no.7
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    • pp.800-808
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    • 2019
  • Charcot-Marie-Tooth disease (CMT) is a group of rare peripheral neuropathies characterized by progressive muscle weakness and atrophy and areflexia in the upper and lower extremities. The most common subtype of CMT is CMT1A, which is caused by a tandem duplication of the PMP22 gene in the 17p12 region. Patients with CMT1A show a loose genotype-phenotype correlation, which suggests the existence of secondary genetic or association factors. Recently, polymorphisms of rs71428439 (n.83A>G) and rs2292832 (n.86T>C) in the MIR149 have been reported to be associated with late onset and mild phenotypic CMT1A severity. The aim of this study was to examine the intrafamilial heterogeneities of clinical phenotypes according to the genotypes of these two SNPs in MIR149. For this study, we selected 6 large CMT1A families who showed a wide range of phenotypic variation. This study suggested that both SNPs were related to the onset age and severity in the dominant model. In particular, the AG+GG (n.83A>G) and TC+CC genotypes (n.86T>C) were associated to late onset and mild symptoms. Motor nerve conduction velocity (MNCV) was not related to the MIR149 genotypes. These results were consistent with the previous studies. Therefore, we suggest that the rs71428439 and rs2292832 variants in MIR149 may serve as genetic modifiers of CMT1A intrafamilial phenotypic heterogeneity, as they have a role in the unrelated patients. This is the first study to show an association using large families with variable clinical CMT1A phenotypes. The results will be helpful in the molecular diagnosis and treatment of patients with CMT1A.