• The Korean Journal of Physiology and Pharmacology
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• v.9 no.1
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• pp.9-15
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• 2005

We attempted to analyze the mechanism of polychlorinated biphenyl (PCB)-induced neurotoxicity and identify the target molecules in the neuronal cells for PCBs.Since the developing neuron is particularly sensitive to PCB-induced neurotoxicity, we isolated cerebellar granule cells derived from 7-day old Sprague Dawley (SD) rats and grew cells in culture for additional 7 days to mimic PND-14 conditions. Only non-coplanar PCBs at a high dose showed a significant increase of total protein kinase C (PKC) activity at phobol 12,13-dibutyrate ([$^3M$]PDBu) binding assay, indicating that non-coplanar PCBs are more neuroactive than coplanar PCBs in neuronal cells. PKC isozymes were immunoblotted with the selected monoclonal antibodies. PKC-${\alpha}$, ${\delta}$, and ε were activated with non-coplanar PCB exposure. Receptor for activated C kinase-1 (RACK-1), anchoring protein for activated PKC, was more induced with exposure to coplanar PCBs than non-coplanar PCBs. Reverse transcription PCR (RT-PCR) analysis showed induction of neurogranin (RC-3) and growth associated protein-43 (GAP-43) mRNA with non-coplanar PCBs. The results indicate that these factors may be useful biomarkers for differentiating non-coplanar PCBs from coplanar PCBs. The present study demonstrated that non-coplanar PCBs are more neuroactive congeners than coplanar PCBs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.2
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• pp.246-252
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• 1993

Melanoidins, as brown colored polymers, are formed through the diversified reaction systems of Maillard type and other reactions. Melanoidins are important components in relation to food quality and also are known to have antioxidative, mutagenic and antimutagenic activities. Since these aspects have been extensively reviwed elsewhere, only the recent studies regarding to their antioxidative and antimutagenic activities are discussed in this review. Even though their mechanisms are not clearly identified, melanoidins or specific fractions isolated from their mixtures have shown varied antioxidative activities depending on the reaction systems and reaction conditions. Those activities presumely are derived from the complex functional properties of hydrogen / electron donors and metal chelating power, which are originated from their reductone structure and others. It is considered that pyrolysate and other mutagens are formed by the given conditions in some cases during browning reaction, whereas melanoidins and their fractions have antimutagenic effects on chemical and other mutagens. There are positive correlationship among the color intensity, antioxidative activity and antimutagenicity of melanoidins or their fractions. These suggest that the antimutagenicity of melanoidins could be attributed to their antioxidative properties, however, it might also be due to other factors, because the relevant responses for antimutagenicity are very complicate and not clear. Accordingly, further studies are required to determine the actual acitivities and mechanisms involved in antioxidation and (anti)mutagenicity of melanoidins by reaction systems / conditions and by the isolated fractions. And also, additional studies are needed to evaluate the applications of melanoidins and their relevant effects to food and human health.

• Molecules and Cells
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• v.45 no.8
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• pp.522-530
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• 2022

Transposable elements (TEs) account for approximately 45% of the human genome. TEs have proliferated randomly and integrated into functional genes during hominoid radiation. They appear as right-handed B-DNA double helices and slightly elongated left-handed Z-DNAs. Human endogenous retrovirus (HERV) families are widely distributed in human chromosomes at a ratio of 8%. They contain a 5'-long terminal repeat (LTR)-gag-pol-env-3'-LTR structure. LTRs contain the U3 enhancer and promoter region, transcribed R region, and U5 region. LTRs can influence host gene expression by acting as regulatory elements. In this review, we describe the alternative promoters derived from LTR elements that overlap Z-DNA by comparing Z-hunt and DeepZ data for human functional genes. We also present evidence showing the regulatory activity of LTR elements containing Z-DNA in GSDML. Taken together, the regulatory activity of LTR elements with Z-DNA allows us to understand gene function in relation to various human diseases.

• Journal of the Korean Society of Costume
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• v.50 no.5
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• pp.77-90
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• 2000

The purpose of this study is to disclose the dimension of job characteristic, working place situation. and clothes selection, which are variable on clothes selection, to research the relation of job characteristic, working place situation, and clothes selection and to disclose the feature of consumers by each group in accordance with job characteristic. The follows are summary of this study result : The concept structure of job characteristic is composed by four types. Working place situation related with clothes selection are consisted of five types. Professional women selected clothes in accordance with nine feature. Job characteristic is related with working palace situation and influences on clothes selection. The persons influenced by activity state regarded personality as important when select clothes. The persons influenced by duty state regarded harmony and control as important, instead of, they ignored conformity. People select occupation according to individual feature, so the feature of consumers, working place environment, working place situation are different in accordance with job characteristic, as a result we can find differences in clothes selection suitable for working palace and purchasing.

• Journal of Plant Biology
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• v.28 no.4
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• pp.261-270
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• 1985

The portion of Cuscuta japonica haustorium which lies external to the host tissues, the upper haustorium, was investigated at the light- and electron-microscopic levels. The haustorium lightly contacted with the host was formed by the expansion of the epidermis and cortex of the stem at the contact side, and to have a group of meristematic cells within the haustorial cortex. When such a haustorium was closely contacted with the host, the meristematic region transformed into a primordial structure of the endophyte (endophyte primordium, EP) which may penetrate into the host tissues. EP consisted of the three kinds of cell group: dividing cells at the adaxial or proximal side; large, elongate cells (idioblasts) at the middle portion,; compressed cells at the abaxial or basal side. the idioblasts were characterized by the presence of large nucleus, dense cytoplasm, several small vacuoles, and abundant cell organelles including the multilamellar structures and cytosegresomes, and thus suggested to have a high metabolic activity. The features of the EP were discussed in relation to the possibility of the penetrating into host tissues.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6305-6310
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• 2012

Objectives: This study aimed to demonstrate the tyrosine phosphorylation motif (TPM) and 3' region structure of the Helicobacter pylori CagA gene as well as its SHP-2 binding activity in AGS cells and relation to gastric carcinogenesis. Methods: Sixteen clinical isolate H. pylori strains from eight duodenal ulcer and eight gastric adenocarcinoma patients were studied for CagA repeat sequence EPIYA motifs, C-terminal structure, and western blot analysis of CagA protein expression, translocation, and SHP-2 binding in AGS cells. Results: Except for strain 547, all strains from the gastric adenocarcinoma patients were positive for CagA by PCR and had three EPIYA copy motifs. Western blotting showed that all strains were positive for CagA protein expression (100%), CagA protein translocation (100%), and SHP-2 binding (100%). CagA protein expression was significantly higher in the gastric adenocarcinoma patients than in the duodenal ulcer patients (P=0.0023). CagA protein translocation and SHP-2 binding in the gastric adenocarcinoma patients were higher than those in the duodenal ulcer patients, but no significant differences were found between the two groups (P=0.59, P=0.21, respectively). Conclusions: The TPMs and 3' region structures of the H. pylori CagA gene in the duodenal ulcer and gastric adenocarcinoma patients have no significant differences.

• Journal of Microbiology and Biotechnology
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• v.18 no.4
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• pp.676-681
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• 2008

To obtain a natural antioxidant from a marine biomass, this study investigated the antioxidative activity of methanolic extracts from the marine brown alga, Ishige okamurae collected off Jeju Island. A potent free radical scavenging activity was detected in the ethyl acetate fraction containing polyphenolic compounds, and the potent antioxidant elucidated as a kind of phlorotannin, diphlorethohydroxycarmalol, by NMR and mass spectroscopic data. The free radical scavenging activities of the diphlorethohydroxycarmalol were investigated in relation to 1,1-diphenyl-2-picrylhydrazyl (DPPH), alkyl, and hydroxyl radicals using an electron spin resonance (ESR) system. The diphlorethohydroxycarmalol was found to scavenge DPPH ($IC_{50}=3.41{\mu}M$) and alkyl ($IC_{50}=4.92{\mu}M$) radicals more effectively than the commercial antioxidant, ascorbic acid. Therefore, these results present diphlorethohydroxycarmalol as a new phlorotannin with a potent antioxidative activity that could be useful in cosmetics, foods, and pharmaceuticals.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.76.1-76
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• 2003

The coat protein (CP) of Turnip crinkle virus (TCV) is organized into 3 distinct domains, R domain (RNA-binding) connected by an arm, 5 domain and P domain. We have previously shown that the CP of TCV strongly suppresses RNA silencing, and have mapped N-terminal R domain of which is also the elicitor of resistance response in the Arabidopsis ecotype Di-17 carrying the HRT resistance gene. In order to map the region in the TCV CP that is responsible for silencing suppression, a series of CP mutants were constructed, transformed into Agrobacterium, coinfiltrated either with HC-Pro (the helper component proteinase of tobacco etch potyvirus) known as a suppressor of PTGS or GFP constructs into leaves of Nicotiana benthmiana expressing GFP transgenically. In the presence of HC-Pro, all CP mutants were well protected, accumulating mutant CP mRNAs and their proteins even 5 days post-infiltration (DPI). In the presence of GFP, some mutant constructs which showed the accumulation of CP mutants and GFP mRNAs at early stage but eventually degraded at 5 DPI. Only a mutant which carrying 4 amino acid deletion of R domain was tolerable to maintain suppressing activity, suggesting that the suppressing activity is not directly related with the eliciting activity. A transient assay also revealed that the mutants synthesized their proteins, suggesting that a full length of CP sequences and its intact structure are required to stabilize CP, which suppresses the RNA silencing.

• Archives of Pharmacal Research
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• v.11 no.1
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• pp.33-40
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• 1988

Two new nitro analogs of tranylcypromine, (E)-2-(p-nitrophenyl)cyclopropylamine ((E)-p-NTCP) and (E)-2-(m-nitrophenyl)cyclopropylamine ((E)-m-NTCP) were synthesized in order to examine the effect of aromatic nitro substitution on the MAO-inhibitory activity of 2-phenylcyclopropylamines. The compounds were obtained by treating t-butyl (E)-2-(p-nitrophenyl) cyclopropanecarbamate and t-butyl (E)-2-(m-nitrophenyl)cyclopropanecarbamate with p-toluenesulfonic acid in $CH_3$CN. Inhibitions of rat brain mitochondrial MAO-A and B by the compounds were examined using serotonin and benzylamine as the substrate at both in vitro and ex vivo levels. It was found from in vitro measurements that (E)-p-NTCP at $6.0{\times}10^{-5}M$ elicited merely 22.5% inhibition against MAO-B without any effect on MAO-A. In contrast, (E)-m-NTCP showed fair degrees of inhibitions of MAO-A and B with $IC_{50}$ values, $2.5{\times}10^{-7}M\;and\;1.4{\times}10^{-6}M$, respectively. It was also noted from (E)-m-NTCP that m-nitro substitution caused a shift of selectivity of the inhibition toward MAO-A. According to ex vivo measurements at 1.5, 3, 6, and 12 hr following the administration of a dose of 0.015 mmol/kg, i.p. to the rats, the inhibition percents of MAO-A by (E)-m-NTCP were 58.6, 63.7 63.6, and 46.6%, slightly lower than those observed by tranylcypromine. Whereas, (E)-m-NTCP at the same dose level did not show significant inhibitions against both MAO-A and MAO-B. Possible reasons for the difference in potencies between (E)-m-NTCP and (E)-p-NTCP were sought in relation to differing electron withdrawing effects of m- and p-substituents which will influence electron density of the side chain amino functions and the partitions.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.467-473
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• 2011

Flavonoid are large group of the polyphenolic compounds which are distinguished by an aromatic or phenolic ring structure and the phenolic compounds are induced by microbial infection, ultraviolet radiation, temperature and chemical stress. They are known for their antioxidant activity, anti-allergic, anti-inflammatory, anti-microbial and anti-cancer activities. In this study, changes in flavonoid content were investigated using heterologous chalcone isomerase (CHI) expression system. Also, phenolic compounds level was measured to examine the relation between flavonoids and phenols contents. Explants of lettuce (Lactuca sativa L.) were transformed with Agrobacterium tumefaciens LBA 4404 strain containing pFLH-CHI (derived from pPZP2Ha3) vector constructed with CHI gene from Brassica rapa. The putative transgenic plants were confirmed by genomic DNA PCR analysis. Also the transcription levels of the gene were analyzed by semi-quantitative RT-PCR with gene specific primers. The total flavonoid contents were increased at $T_0$ and $T_1$ generations over 1.4 and 4.0 fold, respectively. Total phenol contents also increased at $T_1$ generation. These results indicate that CHI gene plays an important role to regulate the accumulation of flavonoids and its component changes.