• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5715-5719
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• 2014

Autophagy is crucial in the maintenance of homeostasis and regenerated energy of mammalian cells. Macroautophagy and chaperone-mediated autophagy(CMA) are the two best-identified pathways. Recent research has found that in normal cells, decline of macroautophagy is appropriately parallel with activation of CMA. However, whether it is also true in cancer cells has been poorly studied. Here we focused on cross-talk and conversion between macroautophagy and CMA in cultured Burkitt lymphoma Raji cells when facing serum deprivation and exposure to a toxic compound, arsenic trioxide. The results showed that both macroautophagy and CMA were activated sequentially instead of simultaneously in starvation-induced Raji cells, and macroautophagy was quickly activated and peaked during the first hours of nutrition deprivation, and then gradually decreased to near baseline. With nutrient deprivation persisted, CMA progressively increased along with the decline of macroautophagy. On the other hand, in arsenic trioxide-treated Raji cells, macroautophagy activity was also significantly increased, but CMA activity was not rapidly enhanced until macroautophagy was inhibited by 3-methyladenine, an inhibitor. Together, we conclude that cancer cells exhibit differential responses to diverse stressor-induced damage by autophagy. The sequential switch of the first-aider macroautophagy to the homeostasis-stabilizer CMA, whether active or passive, might be conducive to the adaption of cancer cells to miscellaneous intracellular or extracellular stressors. These findings must be helpful to understand the characteristics, compensatory mechanisms and answer modes of different autophagic pathways in cancer cells, which might be very important and promising to the development of potential targeting interventions for cancer therapies via regulation of autophagic pathways.

• Korean Journal of Medicinal Crop Science
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• v.14 no.4
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• pp.217-220
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• 2006

It is known that the process of variety development and maintenance of original plant is difficult in Angelica gigas and Angelica acutiloba because they are allogamous plants. The contents like this are stand in the way of theirs breeding. This study was conducted to investigate the foraging activity and pollinational efficacy by insects to flowers of A. gigas and A. acutiloba. Foraging activity by pollinators was observed every day from 10:00 to 10:30 during 3 days after September 21. Honey bee and fly were major pollinators. The rate of hymenoptera and diptera to total numbers of insects was the 56.5% and 40.6% in A. gigas, respectively. It was also 46.3% and 51.8% in A. acutiloba, respectively. The other insects were lepidoptera, coleoptera and hemiptera. The numbers of hymenoptera and diptera were more in flowers of A. gigas was 49.2% with bee, 36.0% with fly, 15.3% with human, 0.9% without anything in the nethouse and 76.6% in the open field. That of A. acutiloba was 43.6% with bee, 27.9% with fly, 20.3% with human, 0.6% without anything in the nethouse and 46.9% in the open field. Excepting open field, seed setting rate of with bee in the nethouse was the highest of all the others. However, we concluded that the use of fly was the most effective method for pollination of A. gigas and A. acutiloba considering low cost and convenient handling.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.944-949
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• 1995

To investigate the effect of processing on the antimutagenicity of rice, antimutagenic effect of rice products including cooked rice, plain steamed rice bread(baikseolgi) and parched rice powder were observed. They showed inhibitory effects of $46%{\sim}100%$ on the frameshift mutation, whereas they showed little inhibitory effect on the base substitution mutation in the Salmonella typhimurium reversion assay. No inhibitory effect was found in the SOS chromotest. Inhibitory effect was more clearly observed on the indirect-acting mutagen than on the direct-acting mutagen. In case of the S. typhimurium reversion assay, the range of inhibition rate against the frameshift and base substitution mutation was $75%{\sim}100%$ and $66%{\sim}87%$, respectively, and was $19%{\sim}67%$ in the SOS chromotest. Antimutagenic activity of raw rice was supposed to be maintained in processed rice products.

• Food Science and Preservation
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• v.24 no.7
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• pp.934-941
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• 2017

The objective of this study was to investigate the effect of corrugated packaging coated with aluminum (Al) on quality characteristics of red paprika during storage at $25^{\circ}C$. Characteristics such as weight loss, hardness, total phenolic content, antioxidant activities, polygalacturonic acid (PG) activity, and oxidative enzyme activities (polyphenol oxidase and peroxidase activities) of paprikas, packed in corrugated packaging with or without Al-coating were compared as a function of storage time. Al coating inside of corrugated box was found to inhibit PG activity, resulting in prevention of weight loss and maintenance of hardness of paprika during storage, compared to the control sample. This may be due to Al coating treatment that enhance moisture-proof property and hinder gas transmission of corrugated packaging. Furthermore, paprika in Al-coated-corrugated packaging was lower in oxidative enzyme activities than the control, which caused higher total phenolic content and antioxidant activities during storage. As a results, the Al coated-corrugated packaging can be used as a functional packaging material to extend the shelf-life and improve the storage quality of paprika by preventing their respiration and transpiration.

• Journal of Life Science
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• v.20 no.3
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• pp.388-395
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• 2010

Cyclooxygenase (COX)-2 is generally known as an inducible enzyme, and it produces arachidonic acid to prostaglandin $E_2$ ($PGE_2$), which has been demonstrated to play a critical role in inflammation. In the present study, we investigated the effects of the extracts of fermented beans including soybean (FS), black agabean (FBA) and yellow agabean (FYA), on the expression of COXs and production of $PGE_2$ in U937 human promonocytic cells. Treatment of phorbol 12-myristate 13-acetate (PMA) significantly induced pro-inflammatory mediators such as COX-2 expression and $PGE_2$ production, whereas the levels of COX-1 remained unchanged. However, pre-treatment with FS, FBA and FYA significantly decreased PMA-induced COX-2 protein as well as mRNA, which is associated with inhibition of $PGE_2$ production. Moreover, FS, FBA and FYA markedly prevented the increase of nuclear translocation of nuclear factor kappa B (NF-${\kappa}B$) p65 by PMA. Our data indicate that the extracts of fermented beans exhibits anti-inflammatory properties by suppressing the transcription of pro-inflammatory cytokine genes through the NF-${\kappa}B$ signaling pathway.

• Journal of Chest Surgery
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• v.31 no.5
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• pp.441-450
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• 1998

The medullospinal tract cells are known to play an important role in the control of the cardiovascular activities. To clarify the modes of action of the neurotransmitters on these cells, glutamate, GABA(${\gamma}$-aminobutyric acid) and bicuculline were applicated iontophoretically into the rostral ventrolateral medulla in adult cats anesthetised with ${\alpha}$-chloralose. Followings are the results obtained : 1. The spontaneous activities of the cardiac-related neurons in rostral ventrolateral medulla (RVLM) were increased by the glutamate and decreased by the GABA. 2. Bicuculline, an antagonist of GABA, alone didn't increase the frequency of the action potentials, but could reverse the cellular response to the GABA, simultaneously applicated. 3. GABA seemed to decrease the peak as well as the basal discharge of the neurons in RVLM, but hardly changed their periodicities. 4. The cellular responses of RVLM evoked by the peripheral nerve stimulation could be inhibited by the iontophoretically released GABA. In conclusion, GABA seemed to act as an inhibitory neurotransmitter on the cardiac- related neurons in RVLM of the cats anesthetized with ${\alpha}$-chloralose. But the maintenance of the periodicities of these cells after the application of bicuculline suggested that the afferent activity of the baroreceptor didn't play a key role in the spontaneous activities of the RVLM neurons.

• Journal of Life Science
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• v.21 no.2
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• pp.194-201
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• 2011

Caudal-related homeodomain proteins play critical roles in intestine development and maintenance from Drosophila to humans. The loss or reduction of CDX1 and CDX2 are known to be associated with colon cancers. It has been well known that colorectal carcinogenesis is associated with serious oxidative stress and that catalase is decreased in colon carcinomas. However, the underlying molecular mechanisms remain elusive. Here, we report that Caudal-related homeodomain proteins positively regulate catalase expression in both Drosophila and humans. We found that Drosophila caudal heterozygotes have a decreased catalase expression and increased ROS generation in the hindgut, and that the overexpression of Caudal increases catalase promoter activity and catalase mRNA levels. We also found that CDX1 and CDX2 up-regulate catalase promoter activity and protein levels in HCT116 cells - human colorectal carcinoma cell lines. The level of catalase protein in several colorectal carcinoma cell lines was associated with CDX1 expression. These results suggest that CDX1 and CDX2 may be involved in intestinal homeostasis and tumorigenesis via regulation of catalase expression.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.715-721
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• 2021

Cognitive impairment and Alzheimer's disease are serious social problems associated with the rising elderly population in Korea. 1,2,3,4,6-Penta-O-galloyl-β-ᴅ-glucopyranose (PGG) is a gallotannin isolated from medicinal plants such as Rhus chinensis. This study was performed to evaluate the effect of PGG on biomarkers related to cognitive function in human neuroblastoma SK-N-SH cells. Inhibition of acetylcholinesterase (AChE) activity is considered to be one of the main therapeutic strategies. PGG inhibited AChE activity in the test tube as well as in SK-N-SH cells. In addition, PGG induced protein and mRNA expression of brain-derived neurotrophic factor (BDNF), which is a mammalian neurotrophin that plays major roles in the development, maintenance, repair, and survival of neuronal populations. As one of the underlying molecular mechanisms that induce BDNF expression, PGG induced the activation of Ca²⁺/calmodulin (CaM)-dependent protein kinase II (CaMKII)-cAMP response element binding protein (CREB) pathway. In conclusion, PGG may be an useful material for improving cognitive function.

• Korean Journal of Microbiology
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• v.55 no.2
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• pp.103-111
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• 2019

DNA methylation is involved in diverse processes in bacteria, including maintenance of genome integrity and regulation of gene expression. CcrM, the DNA methyltransferase conserved in Alphaproteobacterial species, carries out $N^6$-adenine or $N^4$-cytosine methyltransferase activities using S-adenosyl methionine as a co-substrate. Celeribacter marinus IMCC12053 from the Alphaproteobacterial group was isolated from a marine environment. Single molecule real-time sequencing method (SMRT) was used to detect the methylation patterns of C. marinus IMCC12053. Gibbs motif sampler program was used to observe the conversion of adenosine of 5'-GANTC-3' to $N^6$-methyladenosine and conversion of $N^4$-cytosine of 5'-GpC-3' to $N^4$-methylcytosine. Exocyclic DNA methyltransferase from the genome of strain IMCC12053 was chosen using phylogenetic analysis and $N^4$-cytosine methyltransferase was cloned. IPTG inducer was used to confirm the methylation activity of DNA methylase, and cloned into a pQE30 vector using dam-/dcm- E. coli as the expression host. The genomic DNA and the plasmid carrying methylase-encoding sequences were extracted and cleaved with restriction enzymes that were sensitive to methylation, to confirm the methylation activity. These methylases protected the restriction enzyme site once IPTG-induced methylases methylated the chromosome and plasmid, harboring the DNA methylase. In this study, cloned exocyclic DNA methylases were investigated for potential use as a novel type of GpC methylase for molecular biology and epigenetics.

• Journal of Ginseng Research
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• v.45 no.2
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• pp.344-353
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• 2021

Background: Korean Red ginseng extract (KRGE) has beneficial effects on the cardiovascular system by improving endothelial cell function. However, its pharmacological effect on endothelial cell senescence has not been clearly elucidated. Therefore, we examined the effect and molecular mechanism of KRGE on the senescence of human umbilical vein endothelial cells (HUVECs). Methods: HUVECs were grown in normal or KRGE-supplemented medium. Furthermore, they were transfected with heme oxygenase-1 (HO-1) gene or treated with its inhibitor, a NF-κB inhibitor, and a miR-155-5p mimic or inhibitor. Senescence-associated characteristics of endothelial cells were determined by biochemical and immunohistochemical analyses. Results: Treatment of HUVECs with KRGE resulted in delayed onset and progression of senescence-associated characteristics, such as increased lysosomal acidic β-galactosidase and decreased telomerase activity, angiogenic dysfunction, and abnormal cell morphology. KRGE preserved the levels of anti-senescent factors, such as eNOS-derived NO, MnSOD, and cyclins D and A: however, it decreased the levels of senescence-promoting factors, such as ROS, activated NF-κB, endothelial cell inflammation, and p21 expression. The beneficial effects of KRGE were due to the induction of HO-1 and the inhibition of NF-κB-dependent biogenesis of miR-155-5p that led to the downregulation of eNOS. Moreover, treatment with inhibitors of HO-1, NF-κB, and miR-155-5p abolished the anti-senescence effects of KRGE. Conclusion: KRGE delayed or prevented HUVEC senescence through a signaling cascade involving the induction of HO-1, the inhibition of NF-κB-dependent miR-155-5p biogenesis, and the maintenance of the eNOS/NO axis activity, suggesting that it may protect against vascular diseases associated with endothelial senescence.