• Journal of Plant Biology
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• 제17권4호
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• pp.163-170
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• 1974

Leaf tissue of Glycine max Merr. was fixed in para-formaldehyde-glutarldehyde and postfixed in osmium tetroxide or postassium permanganate for electron microscopy. The origin of cytolysome-like organelles of mesophyll cell was studied and changes of fine structure of the organelles according to treating solutions such as gibberellin (GA), kinethin (KI), 2,4-dichlorophenoxy acetic acid(2, 4-D) or 2, 4-D＋GA(1mg/l, respectively) were observed. The cylolysome-like organelles differentiate in endoplasmic reticulum and plasmalemma, and they drop into vacuoles being isolated from the formers. They seem to change into myelin-like structure and to be degenerated by autodigestion. Cytolysome-like organelles involved in cell walls and vacuoles showed activity of acid phosphatase. In the group of GA and KI treatment, cytolysome-like organelles were similar to that of the control group. But in the treatmental groups of 2,4-D and 2,4-D＋GA, myelin-like structures increased in size and autodigestion of this organelles were similar to that of the control group. But in the treatmental groups of 2,4-D and 2,4-D＋GA, myelin-like structures increased in size and autodigestion of this organelle seemed to be accelerated. In the treatmental group of 2,4-D＋GA, myelin-like structures shown high electron density were observed in cytoplasm and vacuoles together.

• Reproductive and Developmental Biology
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• 제34권1호
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• pp.47-53
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• 2010

Glycoprotein hormones have a common $\alpha$-subunit that is involved in the signaling pathway together with G protein, adenylcyclase and cAMP induction; however, it is an unclear how this common structure is related to hormonal action. To determine the biological functions of the COOH-terminal amino acids in the $\alpha$-subunit of these glycoprotein hormones, a tethered-molecule was constructed by fusing the $NH_2$-terminus of the $\alpha$-subunit to the COOH-terminus of the $\beta$-subunit of equine chorionic gonadotropin (eCG). The following deletion mutants were created by PCR; Ile was inserted at position 96 to form ${\Delta}96$, Lys was substituted at position 95 to form ${\Delta}95$, His was inserted at position 93 to form ${\Delta}93$ and Tyr was substituted at position 87 to form ${\Delta}87$. Each mutant was transfected into CHO-K1 cells. Tethered-wt eCG, and ${\Delta}96$, ${\Delta}95$, and ${\Delta}93$ mutants were efficiently secreted into the medium but the ${\Delta}87$ mutant was not secreted. Interestingly, the RT-PCR, real-time PCR, and northern blot analyses confirmed that the RNA was transcribed in the ${\Delta}87$ mutant. However, the ${\Delta}87$ mutant protein was not detected in the medium or the intracellular fraction of the cell lysates. The LH- and FSH-like activities of the recombinant proteins were assayed in terms of cAMP production using rat LH/CG and rat FSH receptors. The metabolic clearance rate (MCR) was determined by injecting rec-eCG (2 IU) into the tail vein. The ${\Delta}95$ and ${\Delta}93$ mutants were completely inactive in both the LH- and FSH-like activity assays. The ${\Delta}96$ mutant showed slight activity in the LH-like activity assay. In comparison to the wild type, the activity of the ${\Delta}96$ mutant in the FSH-like activity assay was the highest among all the mutants. The MCR assay in which rec-eCG was injected showed a peak at 10 min in all the treatment groups, which disappeared 4 h after injection. These results imply a direct interaction between the receptor and the COOH-terminal region of the a-subunit. The data also reveal a significant difference in the mechanism by which the eCG hormone interacts with the rLH and rFSH receptors. The COOH-terminal region of the $\alpha$-subunit is very important for the secretion and functioning of this hormone.

• 생명과학회지
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• 제30권5호
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• pp.468-475
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• 2020

본 연구에서는 홍국색소의 항산화 활성 및 조골세포의 분화에 미치는 영향을 검토하였다. 홍국색소의 항산화 활성은 DPPH radical 소거능, ABTS radical 소거능 및 SOD 유사 활성을 측정하여 평가하였다. 홍국색소의 DPPH radical 및 ABTS radical 소거 활성은 농도 의존적으로 증가하였으며, 특히 1,000 ㎍/ml 농도에서 각각 94% 및 99%의 최대 활성을 나타내었다. 또한 SOD 유사 활성을 검토한 결과에서, 홍국색소 1,000 ㎍/ml 농도에서 62%의 최대 활성을 나타내었다. 우선 홍국색소 1~1,000 ㎍/ml의 농도에서 세포독성을 검토하기 위해 MTT assay를 실시한 결과, 1~100 ㎍/ml 농도의 범위에서 세포 독성은 나타나지 않았다. ALP 활성은 1~100 ㎍/ml 농도에서 농도의 존적으로 증가하였으며, 100 ㎍/ml의 농도에서 최대 124%의 활성을 나타내었다. 또한, 석회화 형성능 시험에서도 대조군 대비 모든 농도에서 유의적으로 증가하는 경향이 나타났으며, 100 ㎍/ml의 농도에서 대조군 대비 1.5배의 석회화 형성 결과가 나타났다. 이러한 결과를 통해 홍국색소는 항산화 활성이 우수하며, 조골세포 분화에 긍정적인 영향을 줌으로써 골다공증 예방 소재로서의 개발 가능성을 가진 부가가치가 높은 천연물 소재로 활용 가능할 것으로 생각된다.

• 한국어병학회지
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• 제17권2호
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• pp.75-82
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• 2004

인터페론은 바이러스에 감염된 세포에서 생성되어 다른 세포로 하여금 바이러스의 증식을 억제하는 단백질을 합성하게 하는 사이토카인의 일종으로서 바이러스에 대한 방어작용에서 중요한 역할을 담당한다. 본 연구 결과 강력한 인터페론 유도물질로 알려져 있는 poly inosinic : cytidylic acid (poly I:C)를 잉어에 주사한 결과 SVCV에 대한 항바이러스 활성을 확인할 수 있었다. 즉, Poly I:C 주사구에서 대조구에 비해 누적폐사율이 감소하였으며, 또한 두신백혈구를 분리하여, poly I:C를 처리한 결과 interferon-like cytokine (ILC)이 생성되었다. Crude ILC의 항바이러스 활성을 cytopathic effect reduction (CPER) assay로 조사한 결과, 적정 HKLs 농도는 1×$10^6$cells/ml으로 나타났으며, 20~50$\mu{g}$/ml 농도의 poly I:C를 처리했을 때 유의적으로 증가하였다. ILC 생성을 위한 적정온도 및 FBS의 농도는 각각 20$20^\circ{C}$와 5%로 나타났다.

• 한국환경보건학회지
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• 제45권1호
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• pp.62-70
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• 2019

Objectives: This study was carried out to analyze the cytotoxicity of cadmium sulfate ($CdSO_4$) and the antioxidative effect of Typha orientalis L. (TO) extract on the oxidative stress induced by cytotoxicity of $CdSO_4$ in the cultured NIH3T3 fibroblasts. Methods: For this study, the cell viability and the antioxidative effects such as the inhibitory activity of lipid peroxidation (LP) and superoxide dismutase (SOD)-like activity and xanthine oxidase (XO)-inhibitory activity were assessed. Results: The cadmium sulfate significantly decreased cell viability in dose-dependently, and $XTT_{50}$ value was measured at $47.4{\mu}M$ of $CdSO_4$. The cytotoxicity of $CdSO_4$ was determined as highly toxic by Borenfreund and Puerner's toxic criteria. The butylated hydroxytoluene (BHT) as antioxidant significantly increased cell viability injured by $CdSO_4$-induced cytotoxicity in these cultures. In the protective effect of TO extract on $CdSO_4$-induced cytotoxicity, TO extract remarkably increased the inhibitory ability of LP and XO as well as SOD-like ability. Conclusions: From the above results, it is suggested that the oxidative stress is involved in the cytotoxicity of $CdSO_4$, and TO extract effectively protected $CdSO_4$-induced cytotoxicity by antioxidative effects. The natural component like TO extract may be a putative therapeutic agent for treatment of the toxicity induced by heavy metallic compound like $CdSO_4$ correlated with the oxidative stress.

• 한국환경성돌연변이발암원학회지
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• 제23권2호
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• pp.56-62
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• 2003

The liver progenitor cells could form a potential target cell population fore both tumor-initiating and -promoting chemicals. Induction of drug-metabolizing and antioxidant enzymes, including AhR-dependent CYP1A1, NQO-1 and AKR1C9, was detected in the rat liver epithelial WB-F344 "stem-like" cells. Additionally, WB-F344 cells express a functional, wild-type form of p53 protein, a biomarker of genotoxic events, and connexin 43, a basic structural unit of gap junctions forming an important type of intercellular communication. In this cellular model, two complementary assays have been established for detection of the modes of action associated with tumor promotion: inhibition of gap junctional intercellular communication (GJIC) and proliferative activity in confluent cells. We found that the PAHs and PCBs, which are AhR agonists, released WB-F344 cells from contact inhibition, increasing both DNA synthesis and cell numbers. Genotoxic effects of some PAHs that lead to apoptosis and cell cycle delay might interfere with the proliferative activity of PAHs. Contrary to that, the nongenotoxic low-molecular-weight PAHs and non-dioxin-like PCB congeners, abundant in the environment, did not significantly affect cell cycle and cell proliferation; however both groups of compounds inhibited GJIC in WB-F344 cells. The release from contact inhibiton by a mechanism that possibly involves the AhR activation, inhibition of GJIC and genotoxic events induced by environmental contaminants are three important modes of action that could play an important role in carcinogenic effects of toxic compounds. The relative potencies to inhibit GJIC, to induce AhR-mediated activity, and to release cells from contact inhibition were determined for a large series of PAHs and PCBs and their metabolites. In vitro bioassays based on detection of events on cellular level (deregulation of GJIC and/or proliferation) or determination of receptor-mediated activities in both ?$stem-like^{\circ}{\times}$ and hepatocyte-like liver cellular models are valuable tools for detection of modes of action of polyaromatic hydrocarbons. They may serve, together with concentration data, as a first step in their risk assessment.

• Journal of Microbiology and Biotechnology
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• 제19권10호
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• pp.1169-1175
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• 2009

An antifungal chitinase, ChiCW, produced by Bacillus cereus 28-9 is effective against conidial germination of Botrytis elliptica, the causal agent of lily leaf blight. ChiCW as a modular enzyme consists of a signal peptide, a catalytic domain, a fibronectin type-III-like domain, and a chitin-binding domain. When two C-terminal domains of ChiCW were truncated, $ChiCW{\Delta}FC$ (lacking the chitin-binding domain and fibronectin type III-like domain) lost its antifungal activity. Since $ChiCW{\Delta}C$ (lacking the chitin-binding domain) could not be expressed in Escherichia coli as $ChiCW{\Delta}FC$ did, a different strategy based on protein engineering technology was designed to investigate the involvement of the chitin-binding domain of ChiCW ($ChBD_{ChiCW}$) in antifungal activity in this study. Because ChiA1 of Bacillus circulans WL-12 is a modular enzyme with a higher hydrolytic activity than ChiCW but not inhibitory to conidial germination of Bo. elliptica and the similar domain composition of ChiA1 and ChiCW, the C-terminal truncated derivatives of ChiA1 were generated and used to construct chimeric chitinases with $ChBD_{ChiCW}$. When the chitin-binding domain of ChiA1 was replaced with $ChBD_{ChiCW}$, the chimeric chitinase named ChiAAAW exhibited both high enzyme activity and antifungal activity. The results indicate that $ChBD_{ChiCW}$ may play an important role in the antifungal activity of ChiCW.

• 한국응용과학기술학회지
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• 제31권1호
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• pp.130-135
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• 2014

천연에서 유래한 항산화 및 항용혈 소재개발을 위해 복분자 에탄올 추출물의 생리활성 효능 평가를 실시하였다. 복분자를 에탄올 추출한 후, 획득한 추출물을 섬유아세포주인 HS68에 처리하여 DPPH 라디칼 소거능과 SOD 유사 항산화 효능을 평가하였다. 또한 Sprague Dawley 렛트 적혈구 세포에 과산화수소로 산화를 유도한 후 추출물의 항용혈 효능을 살펴보았다. 그 결과 추출물은 농도 의존적으로 DPPH 라디칼 소거능과 SOD 유사 활성이 증가하는 것으로 나타났다. 렛트 적혈구를 이용한 항용혈 평가에서는 과산화수소를 단독으로 처리한 양성대조군보다 추출물을 처리한 군에서 항용혈율이 농도 의존적으로 유의하게 증가하였다. 이들 결과는 복분자 추출물이 항산화효능과 항용혈 약용 식물 소재로서의 가능성을 내는 것으로 사료된다.

• 대한본초학회지
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• 제31권6호
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• pp.21-28
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• 2016

Objectives : This study was performed to investigate the antioxidant activity of water extracts from Lycopus lucidus Turcz. ex Benth. leaves, stems and roots at the $100{\mu}g/m{\ell}$ concentration. Methods : The different part of Lycopus lucidus Turcz. ex Benth. extract was prepared using water. The antioxidant activities of polyphenol contents, total flavonoid contents, DPPH(1,1-diphenyl-2-picrylhydrazyl) free-radical scavenging activity, SOD like activity, hydroxyl radical, ABTS(2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), $Fe^{2+}$ chelating, and nitrite scavenging activity. Results : The total polyphenol and total flavonoid content of leaves were the highest at $221.85{\mu}g/mg$ and $794.13{\mu}g/mg$, respectively. Electron donating ability was the 79.68% in the water extract from leaves. The ABTS radical scavenging activity of the hot extracts, leaves ${\gg}$ roots > stems was higher in the order. It was shown the highest at 94.53% in the water extract from leaves, which showed a value equal to 94.7% of ascorbic acid. The hydroxyl radical scavenging activity was the highest at 8.07% in the water extract from leaves. SOD like activity and $Fe^{2+}$chelating activity were leaves of 12.3% and 27%, respectively, which were much higher than those of any other parts. The nitrite scavenging ability of extracts was increased at pH 2.5, and those was the highest in leaves of 83.03%. Its were more than twice the 41.61% of BHT. Conclusion : The results suggest that Lycopus lucidus Turcz. ex Benth. can be used as nutraceutical foods and natural antioxidant.

• Food Science and Biotechnology
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• 제17권3호
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• pp.608-612
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• 2008

In Korea and China, cherry elaeagnus (Elaeagnus multiflora Thunb.) has been used traditionally to treat cough, diarrhea, itching, and foul sores. Therefore, in this study, the ethanol and water extracts of cherry elaeagnus leaves were examined for their antioxidant activities. The ethanol extract of the cherry elaeagnus leaves contained more phenolics than the water extract. All the cherry elaeagnus leaf extracts had higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability than ascorbic acid at concentrations of $250-1,000\;{\mu}g/mL$. The ethanol extract also showed higher superoxide dismutase (SOD)-like activity compared to the water extract. Furthermore, the SOD-like activity of the ethanol extract amounted to 89% of that of ascorbic acid at a concentration of $500\;{\mu}g/mL$. The nitrite scavenging ability and xanthine oxidase inhibitory (XOI) activity of the ethanol extract were higher than those of the water extract. In particular, the ethanol extract had higher XOI activity than ascorbic acid at a concentration of $1,000\;{\mu}g/mL$.