• Journal of Photoscience
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• 제9권2호
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• pp.527-529
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• 2002

Photodynamic therapy (PDT) is a medical treatment using laser and photosensitizing drug taken up to destroy cancer cells. Singlet oxygen ($^1$0$_2$) generation is strongly related to this treatment. We have built a direct detection system monitoring feeble luminescence, in the near IR region, from $^1$0$_2$, We have comparatively studied the photophysical and photochemical properties in solution of a newly developed drug ATX-S10 and Photofrin already investigated clinically. We demonstrdted that ATX-S10 was capable of efficiently yielding $^1$0$_2$, which may lead to highly efficient PDT treatment. Successive laser excitation photobleached ATX -S10 readily in a dose-dependent manner. This result shows that ATX -S10 is useful in setting up suitable medical treatment conditions to minimize side effects.

• 생명과학회지
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• 제21권10호
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• pp.1377-1384
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• 2011

Astaxanthin (ATX)은 다양한 생명체에서 생성되는 카로티노이드 색소이다. 본 연구에서는 ATX가 RAW264.7 cell에서 LPS에 의한 inducible nitric oxide synthase (iNOS), nitric oxide (NO), 염증성 사이토카인, nuclear factor-kappa B (NF-${\kappa}B$)와 reactive oxygen species (ROS)의 생성을 억제 시키는 지 또한, superoxide radical 소거능이 있는 지를 조사하였다. iNOS와 NF-${\kappa}B$는 immunoblot analysis로, interleukin (IL)-6와 tumour necrosis factor-${\alpha}$ (TNF-${\alpha}$)는 ELISA 법으로 분석하였다. NO 양은 nitrite의 양을 측정하였고, ROS는 2',7'-dichlorodihydrofluorescin diacetate (DCFH-DA) 법으로 superoxide radical 소거능은 superoxide radical scavenging activity assay로 검증하였다. 100 ${\mu}M$의 ATX 농도에서 LPS로 유도된 NO, IL-6 및 TNF-${\alpha}$ 같은 염증성 사이토카인의 생성 뿐만 아니라 iNOS 및 NF-${\kappa}B$의 발현도 억제되었다. 특히, IL-6 및 TNF-${\alpha}$ 생성에 있어 ATX의 최대 억제율은 각각 65.2% 및 21.2% 이었으며 LPS로 유도된 NF-${\kappa}B$의 전사활성을 억제하였다. 이러한 현상은 세포질에서 핵으로 NF-${\kappa}B$의 전위를 억제하는 것과 관련이 있다. 또한, 25-100 ${\mu}M$의 ATX 농도에서 세포 내 ROS 생성을 억제하였으며, 5 mg/ml 농도의 ATX는 동일농도의 ${\alpha}$-tocopherol에 비해 superoxide radical 소거능이 1.33배 높았다. 이러한 결과들은 ATX가 대식세포에서 ROS 생성 및 NF-${\kappa}B$ 활성을 저해하므로 iNOS의 발현, NO 및 염증성 사이토카인의 생성을 억제하며, 또한 우수한 superoxide radical 소거능을 보유한다는 것을 나타내었다. 결론적으로, ATX가 항염증제 및 항산화제로서 유용하게 사용될 수 있을 것으로 사료된다.

• Journal of Photoscience
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• 제9권2호
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• pp.515-517
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• 2002

Photodynamic therapy (PDT) is a cancer treatment modality which utilizes the cytotoxicity of the active singlet oxygen derived from irradiation of a tumor accumulated photosensitizer. As the oxygen in the singlet state radiates an emission of 1270nm wavelength when it decays to the triplet state, detection of the emission helps us to understand the mechanism of PDT or to evaluate photosensitizers. We detected the 1270nm emission from photosensitizers Photofrin and ATX-SI0 in vitro and in vivo by means of high sensitive NIR detectors. We obtained the maximum amount of singlet oxygen at irradiation wavelength of 665-670nm from a HeLa tumor in a nude mouse which is injected with ATX-S10.

• 대한방사선방어학회:학술대회논문집
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• 대한방사선방어학회 2011년도 추계 학술발표회 및 심포지엄
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• pp.212-213
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• 2011

The biological effects of low dose ionizing radiation (LDIR) remain insufficiently understood. We examined for the scientific evidence to show the biological effects of LDIR using radiation-sensitive immune cells. We found that Ikaros protein was responsed to low dose-dependent effects of gamma radiation in IM-9 B lymphocytes. Ikaros encodes zinc finger transcription factors that is important regulators of a hematopoietic stem cells (HSCs) progression to the B lymphoid lineage development, differentiation and proliferation. In this study, we observed that cell proliferation was enhanced from 10% to 20% by LDIR (0.05 Gy) in IM-9 B lymphocytes. The Ikaros protein was phosphorylated in its serine/threonine (S/T) region and decreased its DNA binding activity in the cells exposed to LDIR. We found that Ikaros phosphorylation was up-regulated by CK2/AKT pathway and the residues of ser-304 and ser-306 in Ikaros was phosphorylated by LDIR. We also observed that Ikaros protein was localized from the nucleus to the cytoplasm after LDIR and bound with Autotaxin (ENPP2, ATX) protein, stimulating proliferation, migration and survival of immune cells. In addition, we found that the lysoPLD activity of ATX was dependent on Ikaros-ATX binding activity. These results indicate that the Ikaros is an important regulator of immune activation. Therefore, we suggest that low dose ionizing radiation can be considered as a beneficial effects, stimulating the activation of immune cells.

• Journal of Microbiology and Biotechnology
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• 제27권2호
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• pp.316-320
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• 2017

Alternariol monomethyl ether (AME), a dibenzopyrone derivative, was isolated from Alternaria brassicae along with altertoxin II (ATX-II). The compounds were tested for the inhibitory activity of monoamine oxidase (MAO), which catalyzes neurotransmitting monoamines. AME was found to be a highly potent and selective inhibitor of human MAO-A with an $IC_{50}$ value of $1.71{\mu}M$; however, it was found to be ineffective for MAO-B inhibition. ATX-II was not effective for the inhibition of either MAO-A or MAO-B. The inhibition of MAO-A using AME was apparently instantaneous. MAO-A activity was almost completely recovered after the dilution of the inhibited enzyme with an excess amount of AME, suggesting AME is a reversible inhibitor. AME showed mixed inhibition for MAO-A in Lineweaver-Burk plots with a $K_i$ value of $0.34{\mu}M$. The findings of this study suggest that microbial metabolites and dibenzopyrone could be potent MAO inhibitors. In addition, AME could be a useful lead compound for developing reversible MAO-A inhibitors to treat depression, Parkinson's disease, and Alzheimer's disease.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.79-79
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• 2017

Grain Sorghum varieties grown in Korea have low productivity and are constrained by the fact that farmers' choice of improved varieties is limited. Hybrid cultivars have been demonstrated to be more productive and food security than pure line varieties. However, There's no available hybrid cultivars and never planted before in Korea. This study was, therefore, conducted to determine combining ability of Korean landrace varieties and cultivar, the level of heterosis of experimental hybrids depending on environments. Two cytoplasmic male-sterile lines were crossed with six male-fertile lines in accordance with North Carolina II mating scheme to generate 12 experimental hybrids. The hybrids were evaluated in replicated row-column alpha designs at two sites in Texas and South Korea under on-season production conditions. For each trait, general combining ability (GCA) and specific combining ability (SCA) effects were estimated using the line-tester method of analysis. Results indicated significant differences among genotypes for both grain yield potential and secondary traits. Hybrids were predominant for grain yield, and displayed up to 127% heterosis of A03017 ${\times}$ Sodamchal in Korea. Positive GCA for yield was observed for Donganme, Hwanggeumchal and Jungmo4002 in Korea. Among them Jungmo4002 and Donganme had highly positive for yield (227.90 and 84.90 kg ha-1), while it showed negative GCA for yield in College station (-40.90, -189.60 kg ha-1). ATx630 ${\times}$ Sodamchal had the greatest SCA for yield (468.10 kg/ha) in College station but at South Korea its SCA effect was -302.40 kg/ha. A similar trend was observed, followed by A03017 ${\times}$ Donganme (SCA effect = 215 kg ha-1 at College station vs. -44.20 kg ha-1 at South Korea). At South Korea the greatest positive SCA effect for grain was observed in ATx630 ${\times}$ Jungmo4002 as 322.20 kg/ha. Both GCA and SCA effects significantly interacted with site effects demonstrating the need for region adaptation of potential cultivars and test for developing Korea suitable cultivar.

• 공업화학
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• 제10권7호
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• pp.963-968
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• 1999

CFCs(chlorofluorocarbons)에 의한 여러 지구 환경문제들이 발생되고 있는 가운데, 사용후 회수된 CFCs에 대하여 보다 안전한 파괴방법이 요구되고 있다. 이런 관점에서 CFC-113의 분해를 위한 보다 좋은 조건을 개발하고자 접촉 산화분해반응하에서 솔-젤법으로 만들어진 에어로젤 $TiO_2-SiO_2(ATS)$ 촉매에 대하여 본 연구를 행하였다. 솔-젤법으로 만들어진 ATS 촉매가 초기 활성에서 우수하였지만 반응시간이 경과함에 따라 침전법에 의해 제조된 촉매보다 급격한 활성저하를 나타내었다. 이런 비활성화의 원인은 SEM-EDX와 XRD의 분석으로부터 생성가스 $F_2$에 의한 촉매표면의 Si 원자에 대한 결합, 유출에 기인된 것으로 판단되었다. 그리고 ATS 촉매제조과정에서 prehydrolysis 방법으로 처리된 촉매가 촉매 표면의 산성도가 증가됨에 따라 촉매활성이 지속적으로 유지되고 촉매 피독에 의한 비활성화가 느리게 진행되는 것이 관찰되었다. 또한 ATS 촉매 반응에 있어서 Ti의 mol 비가 80%까지 증가함에 따라서도 산성도가 증가되어 본 반응에서 활성 유지와 비활성화 진행속도가 느리게 됨을 발견할 수 있었다. 한편, ATS 촉매에 대해 황산이온처리된 $ATS/SO_4{^{2-}}$ 촉매가 촉매의 활성유지와 비활성화 방지에 있어서 우수한 성질을 나타내었다. 그러므로 본 반응에 있어서 촉매 표면에 대한 황산이온의 처리가 촉매의 비활성화 방지에 기여할 수 있음을 알 수 있었다.