• 한국정밀공학회지
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• 제25권10호
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• pp.33-40
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• 2008

• Asian Pacific Journal of Cancer Prevention
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• 제17권4호
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• pp.2271-2275
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• 2016

Background: The value of 5-aminolevulinic acid (ALA) in fluorescence detection of peritoneal metastases and the underlying mechanisms were evaluated in patients with peritoneal surface malignancies. Materials and Methods: Oral 5-ALA was administered at a concentration of 20 mg/kg body weight with 50 ml of water 2 hours prior to surgery (n=115). The diagnostic value of 5-ALA based fluorescence production was evaluated following white light inspection during prior to cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. Then, peptide transporter PEPT1 (ALA influx transporter) and ATP-binding cassette transporter ABCG2 (porphyrin efflux transporter) gene expression was determined with quantitative real time (qRT)-PCR and pathological diagnoses confirmed for all tissue samples. Results: The 5-ALA based photodynamic detection rate was 17% for appendiceal mucinous neoplasms, 54% for colorectal cancers, 33% for gastric cancers, 67% for diffuse malign peritoneal mesotheliomas, and 89% for epithelial ovarian cancer of peritoneal metastases. 5-ALA was detected in all cases of peritoneal metastases originating from cholangiocarcinomas whereas it was not able to detect any in granulosa cell and gastrointestinal stromal tumor cases. Furthermore, PEPT1 was overexpressed whereas ABCG2 expression was downregulated in tumors detected with fluorescence. Conclusions: 5-ALA provided 100% specificity and high sensitivity to detect peritoneal metastases in subgroups of patients with peritoneal surface mailgnancies. ALA influx transporter PEPT1 and porphyrin efflux transporter ABCG2 genes are important in tumor specific 5-ALA induced fluorescence in vivo. Further studies should clarify diagnostic utility of 5-ALA in peritoneal surface malignancies.

• ALGAE
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• 제33권2호
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• pp.191-203
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• 2018

Fragilariopsis cylindrus is one of the most successful psychrophiles in the Southern Ocean. To investigate the molecular mechanism of biomineralization in this species, we attempted to synchronize F. cylindrus growth, since new cell wall formation is tightly coupled to the cell division process. Nutrient limitation analysis showed that F. cylindrus cultures rapidly stopped growing when deprived of silicate or light, while growth continued to a certain extent in the absence of nitrate. Flow cytometry analysis indicated that deprivation of either silicate or light could effectively arrest the cell cycle of this diatom species at the G1 phase, suggesting that synchrony can be established using either factor. Fluorescence labeling of new cell walls was faintly detectable as early as approximately 6 h after silicon repletion or light irradiation, and labeling was markedly intensified by 18 h. It is revealed that the synthesis of girdle bands begins before valve synthesis in this species, with active valve synthesis occurring during the G2 / M phase. Expression profiling revealed that selective member(s) of the F. cylindrus SIT genes (FcSIT) respond to silicate and light, with a different set of genes being responsive to each factor. The Si / light double depletion experiments demonstrated that expression of one FcSIT gene is possibly correlated to transition to G2 / M phase of the cell cycle, when the valve is actively formed.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2005년도 추계학술대회 및 한일 식물생명공학 심포지엄
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• pp.9-21
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• 2005

To study the biochemical and physiological role of the plastidic glucose transporter (pGlcT) in carbohydrate metabolism, we characterized transgenic plants with mutations in the pGlcT gene (GT), gt-1 and gt-2, as well double mutants of GT and the maltose transporter (MEX1) and GT and the triose phosphate/phosphate translocator (TPT), GT and the cytosolic fructose-1,6-bisphosphatase gene (cFBP), and MEX1 and TPT, gt-1/mex2, gt-1/tpt-2, gt-1/cfbp-1, mex1-1/tpt-2, respectively. Compared to the wild type, all mutants except the gt-1/cfbp-1 mutant lines displayed higher starch accumulation and higher levels of maltose. Starch accumulation is due to a decrease in starch turnover, leading to an imbalance between the rates of synthesis and degradation. Sucrose levels of gt alleles were higher than those in wild-type plants during the light period, suggesting possible nightly supplementation via the maltose transport pathway to maintain proper carbohydrate partitioning in the plant leaves. The gt plants displayed less growth retardation than mex1-1 mutant and gt-1/mex2 double mutant displayed accumulativesevere growth retardation as compared to individual gt-1 and mex1-1 mutants, implying that the maltose transporter-mediated pathway is a major route for carbohydrate partitioning at night. The gt-1/tpt-2, mex1-1/tpt-2 and gt-1/cfbp-1 double mutants had retarded growth and low chlorophyll content to differing degrees, indicating that photosynthetic capacity had diminished. Interestingly, the gt-1/tpt-2 line displayed a glucose-insensitive phenotype and higher germination rates than wild type, suggesting its involvement not only in carbon partitioning, but also in the sugar signaling network of the pGlcT and TPT.

• 천문학회보
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• 제40권1호
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• pp.81.3-81.3
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• 2015

Carbon Fiber Re-enforced Polymer (CFRP) has replaced steel, especially for mobile devices. As CFRP is stiff and light-weight, it has been applied to airplane, sport car, golf clubs, semiconductor transporter, satellites, etc. In the telescope, the plastic material was introduced to the supporting tubes or rods connecting the primary mirror assembly and the secondary mirror structure. Nowadays, even the mirror itself is produced by CFRP. In this poster, material properties and production of CFRP telescopes are presented, and pros and cons are discussed.

• 대한임상검사과학회지
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• 제43권2호
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• pp.33-42
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• 2011

Zinc plays a key role in genetic expression, cell division, and cell growth and is essential for the functions of more than 450 metalloenzyme. There are high concentrations of zinc in pigment epithelium in bullfrog eye. Zinc deficiency causes night blindness and abnormal dark adaptation. The purpose of this study was to identify ERG (electroretinogram) b-wave sensitivity during light and dark adaptation in bullfrog retina after zinc and zinc chelators treatment such as histidine and TSQ (N-(6-methoxy-8-qunolyl)-p-toluenesulfon amide). Especially, we focused whether histidine act as a zinc chelator in the Muller cell. The results of our study are summarized as follows: 1) Both zinc and histidine elevated ERG b-wave amplitude and threshold in Muller cells by accelerating rhodopsin regeneration time and increased a-peak absorbance during light adaptation. 2) TSQ reduced those by prolonging rhodopsin regeneration time and decrement of a-peak absorbance during light adaptation. 3) Zinc shortened rhodopsin regeneration time and prolonged a-peak absorbance. These results suggested that histidine may act as a zinc-mediated transporter in presynaptic Muller cell membrane rather than zinc chelator and acts as a GABA-receptor inhibitor which blocks $Cl^-$ influx to the postsynapse.

• Genomics & Informatics
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• 제21권2호
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• pp.21.1-21.14
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• 2023

Fusobacterium nucleatum is a gram-negative bacteria associated with diverse infections like appendicitis and colorectal cancer. It mainly attacks the epithelial cells in the oral cavity and throat of the infected individual. It has a single circular genome of 2.7 Mb. Many proteins in F. nucleatum genome are listed as "Uncharacterized." Annotation of these proteins is crucial for obtaining new facts about the pathogen and deciphering the gene regulation, functions, and pathways along with discovery of novel target proteins. In the light of new genomic information, an armoury of bioinformatic tools were used for predicting the physicochemical parameters, domain and motif search, pattern search, and localization of the uncharacterized proteins. The programs such as receiver operating characteristics determine the efficacy of the databases that have been employed for prediction of different parameters at 83.6%. Functions were successfully assigned to 46 uncharacterized proteins which included enzymes, transporter proteins, membrane proteins, binding proteins, etc. Apart from the function prediction, the proteins were also subjected to string analysis to reveal the interacting partners. The annotated proteins were also put through homology-based structure prediction and modeling using Swiss PDB and Phyre2 servers. Two probable virulent factors were also identified which could be investigated further for potential drug-related studies. The assigning of functions to uncharacterized proteins has shown that some of these proteins are important for cell survival inside the host and can act as effective drug targets.

• 산업경영시스템학회지
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• 제46권4호
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• pp.160-172
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• 2023

In contemporary global warfare, the significance and imperative of air transportation have been steadily growing. The Republic of Korea Air Force currently operates only light and medium-sized military cargo planes, but does not have a heavy one. The current air transportation capability is limited to meet various present and future air transport needs due to lack of performance such as payload, range, cruise speed and altitude. The problem of population cliffs and lack of airplane parking space must also be addressed. These problems can be solved through the introduction of heavy cargo planes. Until now, most studies on the need of heavy cargo plane and increasing air transport capability have focused on the necessity. Some of them suggested specific quantity and model but have not provided scientific evidence. In this study, the appropriate ratio of heavy cargo plane suitable for the Korea's national power was calculated using principal component analysis and cluster analysis. In addition, an optimization model was established to maximize air transport capability considering realistic constraints. Finally we analyze the results of optimization model and compare two alternatives for force structure.

• Journal of Plant Biotechnology
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• 제48권3호
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• pp.124-130
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• 2021

질산염은 많은 유전자의 발현을 조절하고 생장과 발육과정에서 매우 중요한 영양소이자 시그널 분자이다. 본 연구는 고등식물에서 질산 신호에 의한 유전자발현제어 관련 전사인자의 연구현황을 소개하고자 한다. 질산 환원 효소는 질소 동화 경로상의 효소이며, 질산이온을 아질산이온으로 환원하는 과정을 촉매한다. 질산이온, 빛, 대사산물, 식물호르몬, 저온, 가뭄 등의 여러 요인이 질산환원효소 유전자의 발현 수준과 생리적 역할과 같은 질산환원효소 활성을 조절한다. 최근 질산 환원 효소 유전자의 발현제어에 관여하고 있는 몇몇 전사인자들이 식물에서 분리되었다. NODULE-INCEPTION-like proteins (NLPs)는 질산 환원 효소 유전자의 질산 유도성 발현에 관여하는 전사인자이다. NLPs는 질산 수송체, 아질산 수송체, 아질산 환원 효소에 관련된 유전자의 질산 유도성 발현을 제어한다. 질산 환원 경로와 관련된 유전자의 발현 수준은 질산에 반응하여 NLPs에 의해 협조적으로 조절된다. 따라서 식물에서 질산염의 기능을 이해하면 질소 사용량이 적은 작물을 육성할 수 있다.

• Applied Microscopy
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• 제38권1호
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• pp.29-34
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• 2008

본 연구자는 Zinc Selenium autometallography ($ZnSe^{AMG}$) (Danscher et al., 1997) 염색법을 중심으로 중추신경계통 내 zinc ($Zn^{2+}$)의 분포와 이들을 함유하고 있는 신경종말, 소위 ZEN(zinc-enriched) terminals의 미세구조에 관하여 보고한 바 있다. 이번 연구에서는 다른 몇 가지, 즉 Neo-Timm staining (Danscher, 1982), TSQ fluorescence staining (Frederickson et al.,1987), Zinc transporter-3 Immunohistochemistry ($ZnT3^{IHC}$) (Palmiter et at., 1997) 염색법으로 흰쥐 해마복합체에 분포하는 $Zn^{2+}$를 염색한 후 이들의 염색패턴에서 차이점을 밝히고자 하였다. $ZnSe^{AMG}$ 염색법은 $Zn^{2+}$에 대한 특이성은 다소 떨어지나 광학 및 전자현미경하에서 관찰이 가능하며, 반영구적인 표본으로 보관이 가능하다는 장점이 있었고, TSQ는 $Zn^{2+}$에 대한 특이성이 매우 높을 뿐 아니라 그 염색법이 매우 간단하다는 장점이 있는 반면 형광물질의 안정성과 표본보관이 용이하지 않다는 단점이 있다. 그 외 Neo-Timm 염색법은 TSQ형광염색법과 유사한 염색 패턴을 보였으며, $ZnT3^{IHC}$염색법은 오히려 $ZnSe^{AMG}$에 가까운 염색의 결과를 보였다. 본 연구의 결과는 중추신경계통 내 $Zn^{2+}$에 관한 형태학적 연구에서 기초자료로 활용될 수 있을 것이다.