• Journal of Microbiology
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• 제33권3호
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• pp.222-227
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• 1995

We have examined DNase I sensitivity of .betha.-tubulin and flagellar calmodulin genes which are transiently and coordinately activated differentiation of Naegleria gruberi amebae into flagellates. The DNase I sensitivity of .betha.-tubulin and flagellar calmodulin genes changed in parallel with the changes in transcriptional activity of the respective genes during differentiation. The two genes were resistant to DNase I inamebae stage when transcription of the two genes was inactive. Forthy minutes after initiation of differentiation, when the two genes were most actively being transcribed, the two genes showed the highest sensitsivity to DNase I. One hundred and twenty minutes after initiation, the differentiation was completed and transcriptional activity of the two genes decreased to a low level. At this stage, the two genes were resistant to DNase I treatment like the ones at the amebae stage. This change in the DNase I sensitivity of the two genes was not observed when transcription of the two genes was blocked by adding cycloheximide at the beginning of differentiation.

• Reproductive and Developmental Biology
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• 제30권4호
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• pp.301-305
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• 2006

The aim of this study was to investigate whether addition of porcine epididymal fluid (pEF) into culture medium during in vitro maturation influences the nuclear maturation of porcine germinal vesicle (GV) oocytes. Porcine cumulus-oocyte complexes (COCs) from follicles were cultured in tissue culture medium 199 (TCM 199) containing pEF. After 48hr of culture, oocytes were examined for evidence of GV breakdown, metaphase I, anaphase-telophase I, and metaphase II. The proportion of oocytes reaching at metaphase II (M II) stage was significantly (p<0.05) increased in oocytes cultured in the media supplemented with 10% pEF during in vitro maturation than in those without pEF regardless of cumulus presence or absence (54.6% vs 22.5%, 51.7% vs 24.2%). The supplementation of pEF during maturation of oocyte enhanced oocytes maturation in a dose-dependent manner in vitro. Also significant differences (p<0.05) in the percentage of MII oocytes were observed according to exposure period in pEF. Present study suggests that pEF contains a enhancing component(s) for nuclear maturation of porcine immature oocytes in vitro.

• 한국응용곤충학회지
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• 제45권1호
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• pp.31-36
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• 2006

퇴행성 뇌질환은 뇌에 존재하는 면역세포인 소교세포의 염증반응이 발병 요인 중의 하나로 알려져 있다. 이에 본 연구는 초고속자동화시스템(high throughput screening: HTS)을 이용하여 약용곤충추출물로부터 항산화와 항염증 기능이 있다고 알려진 무당벌레 추출물로부터 염증발생인자인 nitric oxide의 생성에 어떠한 영향을 주는지 다음과 같은 결과를 얻었다. 소교세포인 BV-2세포에 대한 무당벌레 추출물의 세포독성은 물과 메탄올, DMSO 추출물에서는 100 ng/ml 까지는 거의 없었으나 에탄올 추출물은 1 ng/ml에서도 세포독성이 있었다. 물과 메탄을 추출물(50 ng/ml)은 LPS로 활성화된 BV-2세포에서 $TNF-{\alpha}$와 $IL-1{\beta}$의 발생을 35-60% 가량 억제 하였다. LPS로 유도된 NO의 생성은 물과 메탄올 추출물을 처리했을 때 각각 55%, 76% 억제되었다. 또한, MeOH 추출물을 처리했을 경우 LPS에 의한 iNOS 발현 정도를 단백질 수준과 mRNA 수준에서 현저하게 억제시킴을 확인하였다.

• Molecules and Cells
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• 제40권5호
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• pp.355-362
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• 2017

The ${\beta}2$ integrins are cell surface transmembrane proteins regulating leukocyte functions, such as adhesion and migration. Two members of ${\beta}2$ integrin, ${\alpha}M{\beta}2$ and ${\alpha}X{\beta}2$, share the leukocyte distribution profile and integrin ${\alpha}X{\beta}2$ is involved in antigen presentation in dendritic cells and transendothelial migration of monocytes and macrophages to atherosclerotic lesions. ${\underline{R}}eceptor$ for ${\underline{a}}dvanced$ ${\underline{g}}lycation$ ${\underline{e}}nd$ ${\underline{p}}roducts$ (RAGE), a member of cell adhesion molecules, plays an important role in chronic inflammation and atherosclerosis. Although RAGE and ${\alpha}X{\beta}2$ play an important role in inflammatory response and the pathogenesis of atherosclerosis, the nature of their interaction and structure involved in the binding remain poorly defined. In this study, using I-domain as a ligand binding motif of ${\alpha}X{\beta}2$, we characterize the binding nature and the interacting moieties of ${\alpha}X$ I-domain and RAGE. Their binding requires divalent cations ($Mg^{2+}$ and $Mn^{2+}$) and shows an affinity on the sub-micro molar level: the dissociation constant of ${\alpha}X$ I-domains binding to RAGE being $0.49{\mu}M$. Furthermore, the ${\alpha}X$ I-domains recognize the V-domain, but not the C1 and C2-domains of RAGE. The acidic amino acid substitutions on the ligand binding site of ${\alpha}X$ I-domain significantly reduce the I-domain binding activity to soluble RAGE and the alanine substitutions of basic amino acids on the flat surface of the V-domain prevent the V-domain binding to ${\alpha}X$ I-domain. In conclusion, the main mechanism of ${\alpha}X$ I-domain binding to RAGE is a charge interaction, in which the acidic moieties of ${\alpha}X$ I-domains, including E244, and D249, recognize the basic residues on the RAGE V-domain encompassing K39, K43, K44, R104, and K107.

• BMB Reports
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• 제32권2호
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• pp.154-160
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• 1999

A calcium-independent phospholipase $A_2$ ($iPLA_2$) was identified from the cytosolic fraction of rat liver cells. On gel filtration chromatography, the $iPLA_2$ activity was eluted as broad peaks of 150 to 500 kDa. The enzyme was maximally active at pH 7.5, retained 75% of its original activity after heating at $50^{\circ}C$ for 5 h, and was inhibited by $Ca^{2+}$, $Mg^{2+}$, and $Zn^{2+}$ ions, but was not affected by $Na^+$ and $K^+$ ions. The enzymatic activity was increased up to 150% by 1 to 4 mM DTT and was inhibited up to 25% by 0.1 to 1 mM PMSF. The $iPLA_2$ activity had preference for the head group of phospholipids, where phosphatidylethanolamine was preferred to phosphatidylcholine. The results suggest that the $iPLA_2$ may be a novel enzyme distinct from the previously reported $iPLA_2s$.

• BMB Reports
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• 제30권4호
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• pp.285-291
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• 1997

It is becoming increasingly evident that significant changes in gene expression occur during the course of neuronal differentiation. Thus, it should be possible to gain information about the biochemical events by identifying differentially expressed genes in neuronal differentiation The PC12 cell line is a useful model system to investigate the molecular mechanism underlying neuronal differentiation and has been used extensively for the study of the molecular events that underlie the biological actions of nerve growth factor (NGF). In this study, we report an application of the recently described mRNA differential display method to analyze differential gene expression during neuronal differentiation. Using this technique, we have identified several cDNA tags expressed differentially during neuronal differentiation. Interestingly, one of these clones was cytochrome c oxidase subunit I (COX I) gene. The differential expression of COX I gene was confirmed by Northern blot analysis as well as RT-PCR. Southern blot analysis of the genomic DNA of PC12 cells revealed that COX I is a single gene. Induction of the oxidative enzyme might reflect the energy requirement in neuronal differentiation.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1998년도 Advances in Ginseng Research - Proceedings of the 7th International Symposium on Ginseng -
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• pp.253-262
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• 1998

Ochratoxin A (OA) is a potent mycotoxin causing considerable health hazard and economic loss- e,i. OA is of concern as it is hepato-nephrotoxic, mutagenic, and carcinogenic to a great variety of animals. LDso of crude OA was 8.5 mgf kg.b.w., i.p. The clinical symptoms, mortalities and necropsy were recorded in rats injected with OA (LD5o, i.p.) during 10 days of daily treatment. Ginseng treatments (20 mg 1 kg. b.w., i.p.) : before, mixed with, or after OA dose, completely prevented the mortality in rats. OA-treated animals showed microcytic normochromic anaemia, lucocytosis, hypoproteinaemia and elevation of serum ALT, AST, AP, urea, and creatinine values. These findings were declined near the normal levels when ginseng injected with OA. OA (115 LDso) induced chromosomal aberrations (65.66%) compared to the control. When ginseng given 10 min before OA injection, chromosomal aberrations were reduced to be 31.66% compared to OA-treated animals. In conclusion: ginseng has a protective effect against ochratoxicosis, it has anti-genotoxic activity and it can repair the chromosomal damage induced by ochratoxin A. Key words Ochratoxicosis, Chromosomal aberrations, Mycotoxins, Ochratoxin A, Korean gin sting, Protective effect of Panax ginseng, Rat

• Applied Microscopy
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• 제16권2호
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• pp.35-48
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• 1986

Ultrastructures of the cutaneous xanthophores and formation of pigment granules in the goldfish, Carassius auratus L., are studied with electron microscope. The cutaneous xanthophores are observed only in dermis and pigment granules of these pigment cells are pterinosomes and carotenoid vesicles. By the differentiated level, pterinosomes are subdivided into 3 types; while type I pterinosomes have clear limiting membranes and contain some amorphous fine fibrous structures, type II pterinosomes have thick and densely aggregated fibrous materials. Type III pterinosomes have concentric lamellar structures in the granules. Pigment granules of the xanthophores are originated from the Golgi complexes and pinocytotic vesicles of plasma membrane as well as rER-rich cells among the chromatophores are presumed to be associated with the accumulation of pigment materials.

• 대한한의학회지
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• 제21권1호
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• pp.45-52
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• 2000

탁리소독음이 옹저에 있어 항염증 효과를 살펴보고자 NO의 농도, 세포 생존도, iNOS의 표현 및 $TNF-{\alpha}$의 농도를 실험한 결과, NO의 농도는 현저하게 감소하였고 세포 생존도는 탁리소독음에 의하여 영향을 받지 않았으며 iNOS의 표현에 있어서 iNOS의 고도가 현저하게 낮아졌고 $TNF-{\alpha}$의 농도는 현저한 변화가 없었다. 이상을 살펴볼 때 탁리소독음이 옹저에 있어 항염증효과가 있음을 알 수 있었다. 또한 탁리소독음이 충분히 대식세포의 역할을 대신하며 이 이외의 신호경로가 염증기전에 작용한 것으로 생각되며 많은 연구가 요할 것으로 사료된다.

• 식물분류학회지
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• 제40권1호
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• pp.59-64
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• 2010

물봉선속(봉선화과)의 1신종인 꼬마물봉선이 한국의 경상북도 영천시 보현산에서 발견되어 기재되었다. 신종은 근연종인 물봉선(I. textorii)에 비해 1/2 크기의 꽃, 급격히 좁아지는 하악편, 1/2 회에서 1 회 감기는 거, 타원형인 측화판의 선단부 열편을 가짐으로써 뚜렷하게 구별되었다. 본 연구에서 이들 두 종의 검색표를 제시하였다.