• Journal of Microbiology and Biotechnology
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• v.32 no.11
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• pp.1406-1415
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• 2022

The formation of macrophage foam cells stimulated by oxidized low-density lipoprotein (ox-LDL) is deemed an important cause of atherosclerosis. Transcription factor Yin Yang 1 (YY1), which is a universally expressed multifunctional protein, is closely related to cell metabolism disorders such as lipid metabolism, sugar metabolism, and bile acid metabolism. However, whether YY1 is involved in macrophage inflammation and lipid accumulation still remains unknown. After mouse macrophage cell line RAW264.7 cells were induced by ox-LDL, YY1 and proprotein convertase subtilisin/kexin type 9 (PCSK9) expressions were found to be increased while low-density lipoprotein receptor (LDLR) expression was lowly expressed. Subsequently, through reverse transcription-quantitative polymerase chain reaction (RT-qPCR), Western blot analysis, Oil Red O staining and cholesterol quantification, it turned out that silencing of YY1 attenuated the inflammatory response and lipid accumulation in RAW264.7 cells caused by ox-LDL. Moreover, results from the JASPAR database, chromatin immunoprecipitation (ChIP) assay, luciferase reporter assay and Western blot analysis suggested that YY1 activated PCSK9 by binding to PCSK9 promoter and modulated the expression of LDLR in the downstream of PCSK9. In addition, the results of functional experiments demonstrated that the inhibitory effects of YY1 interference on ox-LDL-mediated macrophage inflammation and lipid accumulation were reversed by PCSK9 overexpression. To sum up, YY1 depletion inhibited its activation of PCSK9, thereby reducing cellular inflammatory response, cholesterol homeostasis imbalance, and lipid accumulation caused by ox-LDL.

• Korean Journal of Pharmacognosy
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• v.35 no.2 s.137
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• pp.147-151
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• 2004

Water extracts from Thesium chinense Tunczaninov (TCTW) and Prunella vulgaris L. (PVW) were tested for aromatase and cyclooxygenase activities. TCTW and PVW were capable of suppressing aromatase in a human placenta microsomal assay. PVW was shown to be more effective than TCTW in the suppression of aromatase activity. TCTW significantly inhibited cyclooxygenase-2 (COX-2) activity at the concentration of 0.25 (p<0.05), 0.5 (p<0.01) and 2.5 mg/ml (p<0.005). PVW also inhibited COX-2 activity in a dose-dependent manner in a concentration range of $0.05{\sim}2.5\;mg/ml$. The expression of COX-2 was inhibitied by TCTW and PVW in western blot analysis. These results suggest that TCTW and PVW may have breast cancer chemopreventive potentials by inhibiting aromatase and cyclooxygenase activities.

• International Journal of Industrial Entomology and Biomaterials
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• v.41 no.1
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• pp.1-5
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• 2020

Tumor necrosis factor-α (TNFα) is a representative marker for inflammation. Silk sericin is known as mild TNFα inducer. The purpose of this study was to compare the level of TNFα among different fractions of silk sericin. Silk sericin was extracted from cocoon and separated it by molecular weight. Each fraction was applied to RAW264.7 cells. The level of TNFα was evaluated by western blot and ELISA assay. In results, the level of TNFα was increased as time-dependent manner. Higher molecular weight fraction of sericin induced higher amount of TNFα than lower molecular weight fraction. In conclusion, different molecular weight fraction of sericin induced TNFα differently.

• Microbiology and Biotechnology Letters
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• v.23 no.1
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• pp.110-117
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• 1995

This study was carried out to immunologically characterize Bacillus thuringiensis (B.t) antigens. Protein patterns of ultrasonicated- antigens of B. thuringiensis subspecies using SDS- PAGE revealed marked similarities among all the strains analyzed except for the difference between quantative variations of bands and some protein antigens. The comparison of the protein patterns showed that the protein antigen of 45 kilodalton (kd) was common in 11 strains and that the difference between B. thuringiensis subsp. canadensis and galleriae was noticed in quantative variations of bands despite of ambiguous serogrouping, suggesting a useful method for identification. All strains examined showed similar antigenic patterns in SDS-PAGE, while immunodominant bands differed in antigenic reactivity in western blot using polyclonal antibodies. Polyclonal antibody to B. thuringiensis subsp. thuringiensis and israelensis in indirect immunofluorescence assay reacted with flagella and cell surface antigens. The present study indicates that SDS-PAGE and western blot analysis may be used as tools for differentiation and identification of B. thuringiensis subspecies.

• Journal of Food Hygiene and Safety
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• v.32 no.1
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• pp.75-81
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• 2017

For people who have a food allergy the only way to manage the allergy is to avoid the food allergen. The mackerel is one of the major food allergens, but no immunoassay for the rapid and simple detection of mackerel has been reported. The objectives of this study are to develop and characterize monoclonal antibodies (MAbs) specific to mackerel using thermal stable-soluble proteins (TSSP) as an immunogen and to characterize the MAbs by indirect enzyme-linked immunosorbent assay (iELISA). The mice immunized with mackerel TSSP and showing high titer were used for cell fusion and cloning. The characterization of MAbs produced from hybridoma cells obtained was confirmed by indirect ELISA and western blot. Four MAbs were confirmed to be specific to mackerel without cross-reaction to other marine products and livestock products in the both methods. The iELISA and western blot based on the MAbs can sensitively detect 1% mackerel protein in other marine products. These results support that immunochemical methods based on the MAb produced could be used as rapid means to detect low levels of mackerel and to identify mackerel adulterated in food.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.480-487
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• 1997

Vitellogenin (Vg) was purified from plasma of $estradiol-17\beta(E_2)-treated$ spotted flounder, verasper variegatus, by preripitation with cold distilled water, followed by fractionation using a Sepharose CL-6B column chromatography. $E_2-induced$ protein was identified as Vg by SDS-PAGE and western blot analysis. The molecular weight of the purified Vg was estimated 175 kD as determined by SDS-PAGE. In order to measure the Vg level, monoclonal antibodies against Vg were produced by hybridoma technique. Purified Vg was immunized into Balb/c mice and then the spleen cells from mice were fused with NS-1 myeloma cells. The hybridoma cells were screened by enzyme-linked immunosorbent assay (WLISA) and subcloned by limiting dilution. The hybridoma clones which secreted antibodies highly reactive to the purified Vg were designated as 4D6. Its specificity was demonstrated by western blot from plasma of untreated, $E_2-treated$ male fish, and purified Vg.

• Tuberculosis and Respiratory Diseases
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• v.55 no.5
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• pp.488-498
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• 2003

Background : Activation of the transcription factor NF-${\kappa}B$ has been shown to protect cells from tumor necrosis factor-alpha, chemotherapy, and radiation-induced apoptosis. NF-${\kappa}B$-dependent cIAP expression is a major antiapoptotic mechanism for that. NF-${\kappa}B$ activation and cIAP expression in A549 lung cancer cells which is relatively resistant to radiation-induced cell death were investigated for the mechanism of radioresistance. Materials and methods : We used A549 lung cancer cells and Clinac 1800C linear accelerator for radiation. Cell viability test was done by MTT assay. NF-${\kappa}B$ activation was tested by luciferase reporter gene assay, Western blot for $I{\kappa}B{\alpha}$ degradation, and electromobility shift assay. For blocking ${\kappa}B$, MG132 and transfection of $I{\kappa}B{\alpha}$-superrepressor plasmid construct were used. cIAP expression was analyzed by RT-PCR and cIAP2 promoter activity was performed using luciferase assay system. Results : MTT assay showed that cytotoxicity even 48 hr after radiation in A549 cells were less than 20%. Luciferas assay demonstrated weak NF-${\kappa}B$ activation of $1.6{\pm}0.2$ fold compared to PMA-induced $3.4{\pm}0.9$ fold. Radiation-induced $I{\kappa}B{\alpha}$ degradation was observed in Western blot and NF-${\kappa}B$ DNA binding was confirmed by EMSA. However, blocking NF-${\kappa}B$ using MG132 and $I{\kappa}B{\alpha}$-superrepressor transfection did not show any sensitizing effect for radiation-induced cell death. The result of RT-PCR for cIAP1 & 2 expression was negative induction while TNF-${\alpha}$ showed strong expression for cIAP1 & 2. The cIAP2 promoter activity also did not show any change compared to positive control with TNF-${\alpha}$. Conclusion : We conclude that activation of NF-${\kappa}B$ does not determine the intrinsic radiosensitivity of cancer cells, at least for the cell lines tested in this study.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.7
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• pp.886-890
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• 2017

In this study, the protective effect of rice with Phellinus linteus mycelium (PLMR) against hydrogen peroxide-induced oxidative stress was assessed in a mouse hippocampal neuronal HT22 cell line through (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) salt (MTS) assay and western blot. MTS assay using HT22 cells showed that PLMR extract did not affect viability at a concentration range from 1 mg/mL to 5 mg/mL. However, at concentrations over 10 mg/mL, PLMR extract resulted in increased cell death. Cell viability of HT22 was significantly reduced by $H_2O_2$ treatment, and reduction of cell viability was efficiently restored by treatment with PLMR extract in a dose-dependent manner from 0.1 to 1 mg/mL. Cells treated with $H_2O_2$ showed increased expression of Bax, a pro-apoptotic protein, which was down-regulated by treatment with PLMR extract. On the other hand, cells treated with $H_2O_2$ resulted in reduced expression of Bcl-2, an anti-apoptotic protein, which was restored by treatment with PLMR extract. In addition, treatment with PLMR extract reduced expression of cleaved caspase 3 and PARP, which were up-regulated by $H_2O_2$ treatment. The results may suggest that treatment with PLMR extract would suppress $H_2O_2$-induced apoptosis of HT22 cells.

• Parasites, Hosts and Diseases
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• v.39 no.3
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• pp.261-264
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• 2001

Trichinellosis is a parasitic zoonosis of public health importance. It is caused by Trichinella spiralis which has a wide host range including humans. In the present communication, the ELISA technique was employed on a total of 803 blood samples from 7 selected pig breeding farms in 1996 for diagnosis and surveillance of trichinellosis. Out of the entire 803 samples, nine were found to be suspected while one was positive by ELISA. But western blot analyses employed for further confirmation have shown that all of 10 samples did not react to larval excretory-secretory product antigens. These results indicate that pig breeding farms included in the present study are free from trichinellosis . However, it does not mean Korea is free from trichinellosis since human trichinellosis has recently been reported. The necessity of continued surveillance for trichinellosis in both pigs and wild animals was discussed.