• Animal cells and systems
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• 제4권2호
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• pp.157-163
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• 2000

Yeast pheromone a-factor is a 13-amino acid peptide hormone that is synthesized as a part of a larger precursor, prepro-$\alpha$-factor, consisting of a signal peptide and a proregion of 64 amino acids. The carboxy-terminal half of the precursor contains four tandem copies of mature $\alpha$-factor. To investigate the molecular basis of intracellular sorting, proteolytic processing, and storage of the peptide hormone, yeast prepro-$\alpha$-factor precursors were heterologously expressed in rat pituitary $GH_3 cells. When cells harboring the precursor were metabolically labeled, a species of approximately 27 kD appeared inside the cells. Digestion with peptide: N-glycosidase F (PNG-F) shifted the molecular mass to a 19 kD, suggesting that the 27 kD protein was the glycosylated form as in yeast cells. The nascent polypeptide is efficiently targeted to the ER in the $GH_3 cells, where it undergoes cleavage of its signal peptide and core glycosylation to generate glycosylated pro-a-factor. To look at the post ER intracellular processing, the pulse-labelled cells were chased up to 2 hrs. The nascent propeptides disappeared from the cells at a half life of 30 min and only 10-25% of the newly synthesized, unprocessed precursors were stored intracellularly after the 2 h chase. However, about 20% of the pulse-labeled pro-$\alpha$-factor precursors were secreted into the medium in the pro-hormone form. With increasing chase time, the intracellular level of propeptide decreased, but the amount of secreted propeptide could not account for the disappearance of intracellular propeptide completely. This disappearance was insensitive to lysosomotropic agents, but was inhibited at $16^{circ}C or 20^{\circ}C$, suggesting that the turnover of the precursors was not occurring in the secretory pathway to trans Golgi network (TGN) or dependent on acidic compartments. From these results, it is concluded that a pan of these heterologous precursors may be processed at its paired dibasic sites by prohormone processing enzymes located in TGN/secretpry vesicles producing small peptides, and that the residual unprocessed precursors may be secreted into the medium rather than degraded intracellularly.

• 한국식물학회:학술대회논문집
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• 한국식물학회 2002년도 춘계학술발표대회:발표눈문요지록
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• pp.62-72
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• 2002

This study has investigated the biosynthesis and function of the heavy metal binding peptides, the phytochelatins, in plants. PCs are synthesised enzymatically from glutathione by the enzyme PC synthase in the presence of heavy metal ions. Using Arabidopsis thaliana as a model organism cadmium-sensitive, phytochelatin-deficient mutants have been isolated and characterised in previous studies. The cadl mutants have wildtype levels of glutathione, are PC deficient and lack PC synthase activity. Thus, the CADl gene has been proposed to encode PC synthase. The CADl gene was isolated by a positional cloning strategy The gene was mapped and a candidate identified. Each of four cadl mutants had a single base pair change in the candidate gene and the cadmium-sensitive, cadl phenotype was complemented by the candidate gene. This demonstrated the CADl gene had been cloned. A homologous gene in the fission yeast, Schizosaccharomyces pombe was identified through database searches. A targeted-deletion mutation of this gene was constructed and the mutant, like cadl mutants of Arabidopsis, was cadmium-sensitive and PC-deficient. A comparison of the redicted amino acid sequences reveals a highly conserved N-terminal region Presumed to be the catalytic domain and a variable C-terminal region containing multiple Cys residues proposed to be involved in activation of the enzyme by metal ions. Similar genes were also identified in animal species. The Arabidopsis CADl/AtPCSl and S. pombe SpbPCS genes were expressed in E. coli and were shown to be sufficient for glutathione-dependent, heavy metal activate PC synthesis in vitro, thus demonstrating these genes encode PC synthase enzymes. Using RT-PCR, AtPCSl expression appeared to be independent of Cd exposure. However, at higher levels of Cd exposure a AtPCSl-CUS reporter gene construct appeared to be more highly expressed. Using the reporter gene construct, AtPCSl was expressed most tissues. Expression appeared to be greater in younger tissues and same higher levels of expression was observed in some regions, including carpels and the base of siliques. AtPCS2 was a functional gene encoding an active PC synthase. However, its Pattern of expression and the phenotype of a mutant (or antisense line) have not been determined. Assuming the gene is functional then it has clearly been maintained through evolution and must provide some selective advantage. This implies that, at least in some cells or tissue, it is likely to be the dominant PC synthase expressed. This remains to be determined

• Animal cells and systems
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• 제12권4호
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• pp.269-277
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• 2008

Siberian flying squirrel, an endangered species in South Korea, is distributed through major mountain regions of South Korea. The number of Siberian flying squirrel(Pteromys volans) in South Korea has decreased and their habitats are fragmented and isolated because of anthropogenic activities. So far no molecular genetic data has, however, been available for their conservation and management. To obtain better information concerning genetic diversity and phylogenetic relationships of the Siberian flying squirrel in South Korea, we examined 14 individuals from South Korea, 7 individuals from Russia, and 5 individuals from northeastern China along with previously published 29 haplotypes for 1,140 bp of the mtDNA cytochrome b gene. The 14 new individuals from South Korea had 7 haplotypes which were not observed in the regions of Russia and Hokkaido. The level of genetic diversity(0.616%) in the South Korean population was lower than that in eastern Russia(0.950%). The geographical distribution of mtDNA haplotypes and reduced median network confirmed that there are three major lineages of Siberian flying squirrel, occupying; Far Eastern, northern Eurasia, and the island of Hokkaido. The South Korean population only slightly distinct from the Eurasia, and eastern Russian population, and is part of the lineage Far Eastern. Based on these, we suggest that the South Korean population could be considered to belong to one partial ESU(Far Eastern) of three partial ESUs but a different management unit. However, the conservation priorities should be reconfirmed by nuclear genetic marker and ecological data.

• 한국임상수의학회지
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• 제37권5호
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• pp.242-248
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• 2020

An intestinal strigeiid trematode, Apharyngostrigea pipientis, was detected from Ardea cinerea jouyi, Egretta intermedia and Nycticorax nycticorax between July, 2006 and June, 2020 in Daejeon metropolitan city and Kangwon-do, Republic of Korea. It was observed with a light and scanning electron microscope (SEM), and molecularly analyzed with 18S rRNA genes. The infection rate of the strigeiid trematode was 25.9% (7/27). The body is cylindrical in whole mount, greatly elongated in outline and shows a strong dorsal curvature. The overall measurements are: length 4.1-4.8 mm; fore-body 1.00-1.20 mm by 0.8-0.9 mm; hind-body 3.2-3.6 mm by 0.43-0.46 mm. The body is covered by a relatively thick cuticle, devoid of spines. The oral sucker leads into a short esophagus that is devoid of a muscular pharynx. The holdfast organ is enormously developed. The vitelline follicles distributed dorsal wall of fore-body and hind-body. This strigeiid trematode especially differs from other species of genus Apharyngostrigea in morphology. Although these A. pipientis are several morphological distinctions from Apharyngostrigea cornu, the partial sequence of 18S rRNA showed the sequence homology of A. pipientis (99.9%) and A. cornu (99.8%), and this result revealed their conspecific relationship between A. cornu and A. pipientis. This is the first report of A. pipientis in the Republic of Korea.

• 대한수의학회지
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• 제25권2호
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• pp.113-123
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• 1985

This paper dealt with the distribution of normal mast cells in the spleen, liver and lung on cattle, horses, pigs and dogs, and also degranulation of mast cells in the dogs infected with Rompun (2% Xylazine HCl). The results observed are summarized as follows. Normal mast cells were distributed in spleen, liver and lung on cattle, horse, pig and dog. Mast cells were observed in both red pulp and surroundings of white pulp of the spleen in horse, in the white pulp of the spleen in cattle, in the trabeculae of the spleen in pigs, and in white pulp and red pulp of the spleen in dogs, respectively. Mast cells were observed in the portal triad of the liver in cattle and horses, in both portal triad and interlobular connective tissues of the liver in pigs, and not only the portal triad but also walls of the sinusoids and the central veins in dogs. A large number of mast cells were observed in the interlobular septa and peribronchioles of lung on all the species in this experiment. The mast cells are more numerous in the lungs than other organs. Author considers that numbers of normal mast cells distributed in the tissue is related to the dosage of Rompun in animal. The degranulation of mast cells were observed in the subcutaneous tissues of dog intramuscularly injected with Rompun(0.5ml/times) for 4 or 5 times and subcutaneously injected with Rompun(0.3ml/times) for 4 times. In dog intradermally injected with 0.1ml of Rompun, mast cells were decreased in number at 30 minutes and markedly decreased in number at 2 hours, but more or less increased in number at 3 hours after injection. In addition, the granules of the mast cells were decreased in number at 30 minutes and marked degranulation of the mast cells were recognized at 2 hours after injections, but normal mast cells begun to appear in subcutaneous tissue with the lapse of time from 3 hours after injection. There was also observed local infiltration of neutrophils in subcutaneous tissues of dogs intradermally injected with 0.1ml of Rompun at 30 minutes. At 2 hours after injection, numerous neutrophils and a small number of eosinophils were observed in the site of injection. Conclusionally, Rompun was regarded as a factor which causes the degranulateon of mast cell and the authors considered that histamine released from the mast cells by Rompun might cause relaxation of skeletal muscle.

• 대한수의학회지
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• 제46권3호
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• pp.255-261
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• 2006

Experimental animals have been used to biological and medical purposes and the animals must be, for these purposes, healthy and clean to microbial infection. However, the animals can be easily exposed to pathogenic microorganism via several routes. Of the routes, environmental conditions are the most important factors to keep the animals healthy and clean, especially air condition. Monitoring of air-condition has been required to keep the animal healthy and clean. However, any guideline is not available for experimental conditions with pigs. Therefore, the sampling times and points were compared in different conditions to establish an optimal protocol for monitoring of air borne bacteria. Tryptic soy agar(TSA), blood agar containing 5% defibrinated sheep blood and Sabraud dextrose agar(SDA) were used as media to capture total bacteria, pathogenic bacteria and fungi, respectively. Two methods, compulsive capture using an air-sampler and capturing fall-down bacteria were used to capture the microorganisms in the air. The points and time of capturing were different at each experiment. Air borne microorganisms were captured at three and five points in the open and closed equipments, respectively. Air was collected using an air-sampler for 1 min and 5 min and the agar plates as open status were left from 30 min to 2hr. At first, we monitored an experimental laboratory which dealt with several pathogenic bacteria and then, a protocol obtained from the investigation was applied to open or close experimental conditions with pigs. Number of bacteria was high from 10:00 to 15:00, especially on 13:30-15:30 but sharply decreased after 17:00. The tendency of the number of bacteria was similar between two methods even though the absolute number was higher with air sampler. Critical difference in the number of cells was observed at 5 min with air sampler and 2 hr with fall-down capturing method. However, 1 min with air sampler and 1 hr with fall-down capturing were the best condition to identify bacterial species collected from the air. Number of bacteria were different depending on the sampling points in closed condition but not in opened condition. Based on our results, a guide-line was suggested for screening air-borne microorganism in the experimental conditions with pigs.

• 생명과학회지
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• 제25권6호
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• pp.715-723
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• 2015

지구상에 존재하는 전체 동물 중 가장 큰 부분을 차지 하고 있는 곤충은 예로부터 인간의 식품, 농업, 산업, 의약 등의 일상 생활에 이용되어 왔다. 많은 수와 높은 영양학적 가치로 곤충의 생리활성물질이 미개발 생물자원으로 재평가 되고 있다. 곤충은 면역세포, 곤충 혈구세포, 효소들의 연쇄반응 혹은 항균 단백질/펩타이드 같은 방법으로 외부의 감염에 저항성을 가지게 된다. 항균 펩타이드는 곤충의 혈림프의 선천성 면역 시스템 중 주요한 성분중의 하나로 항생제 내성 균주의 출몰이 빈번하게 일어나 해결책으로 새로운 항생제 개발이 시급한 시점에서 유력한 후보물질로 주목 받고 있다. 곤충 유래 항균 펩타이드는 150개가 넘게 분리되었으며 크게 세크로핀, 디펜신, 글라이신/프롤린이 풍부한 펩타이드로 이루어진다. 이 논문에서, 향균 펩타이드를 생산하는 여러 곤충 중에서 벌, 소똥구리, 울도하늘소, 나비 그리고 울도하늘소에서 얻을 수 있는 펩타이드의 종류 그리고 작용 기작에 대해 알아보았다. 이 펩타이드들은 항균효과를 가지고 있으며 멜리틴을 제외하고 적혈구의 용혈 현상이 나타나지 않고 주로 세포막을 붕괴시키거나 세포자살기작을 유도하여 병원성 미생물의 성장을 억제한다. 곤충 유래 펩타이드와 같은 생리활성물질이 그 활용 가능성의 면에서 엄청난 가능성을 가지고 있어 이에 대한 연구는 앞으로 더 주목을 받을 것이다.

• 한국습지학회지
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• 제16권1호
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• pp.85-92
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• 2014

한국에 서식하는 뱀목(Squamata) 중 살모사과(Viperidae)에 속하는 쇠살모사(Gloydius ussuriensis)와 까치살모사(Gloydius saxatilis)를 대상으로 무선추적기법을 이용한 행동권 연구를 수행하기 위해 모든 개체에게 체중 대비 5% 이내의 발신기를 삽입하였다. 쇠살모사 5개체, 까치살모사 6개체 총 11개체를 대상으로 발신기 삽입수술을 시행한 결과 쇠살모사의 경우 체중 대비 발신기 무게 비율은 평균 4.2%였으며, 까치살모사의 경우 평균 2.2%였다. 발신기삽입 후 회복기간 동안 까치살모사는 모두 생존한 반면 쇠살모사는 전체 5개체 중 4개체가 생존하지 못해 생존율이 20% 밖에 되질 않았다. 이전의 선행 연구들에서는 체중 대비 발신기 무게 비율을 1-7%까지 다양하게 권고하고 있지만, 이번 연구결과는 쇠사모사와 까치살모사의 행동생태 연구에서 이용되는 몸무게에 대한 발신기 무게 비율은 최소 3.6% 이내로 정해야 안전하다는 것을 보여준다.

• The Korean Journal of Physiology
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• 제11권1호
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• pp.27-32
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• 1977

Diospyros Kaki Thunberg is the species of persimmon tree that grows in Korea. Although its fresh or dried fruits are often served as a desert, it has little been known if persimmon tree has any specific pharmacological action. The leaves and branches of persimmon tree has long been used as folk remedies for palsy and frostbite in the southern part of Korea and it is also in use for the treatment of hiccup and nocturnal enuresis in chinese herbal medicine. Recently it was reported that an intravenous administration of Diospyros Kaki Thunberg ethanol extract (KTEE) into the animals lowered arterial blood pressure. Lee concluded from his study on the mechanism of depressor action of KTEE that at least a part of depressor response he observed was caused by acetylcholine-like action of KTEE. On the other hand little study has been made on the effect of KTEE on the motility of isolated animal intestines. Therefore the present study was undertaken to investigate effect of KTEE and the mechanism of its action on the motility of isolated rabbit duodenum. Ethanol extract of Diospyros Kaki Thunberg was prepared by boiling 1 kg of dried branches of persimmon tree in 1 liter of ethanol and the motility of isolated rabbit duodenum was recorded on physiograph by means of force transducer connected with Magnus apparatus. Doses of KTEE used were $5{\times}10^{-4}gm/ml,\;1{\times}10^{-3}gm/ml,\;and\;2{\times}10^{-3}gm/ml$. And the isolated duodenum was separately pretreated with acetylcholine $(5{\times}10^{-7}gm/ml)$, pilocarpine $(2.5{\times}10^{-6}gm/ml)$, histamine $(5{\times}10^{-6}gm/ml)$ and barium chloride $(2.5{\times}10^{-5}gm/ml)$ in order to find out interactions of these drugs with KTEE. The results obtained are as follows: 1. At doses of $5{\times}10^{-4}gm/ml,\;1{\times}10^{-3}gm/ml$ KTEE reduced contractions of isolated duodenum, while tonus as well as contaction of duodenum were depressed with $2{\times}10^{-3}gm/ml$ of KTEE. 2. Since the inhibitory effect of KTEE on the intestinal motility was not blocked by pretreatment with acetylcholine, pilocarpine, and barium chloride, it was strongly suggested that the inhibitory action of KTEE on intestinal motility is mainly Caused by its antihistamine effect. 3. It is also concluded that the principal substance of KTEE responsible for inhibition of intestinal motility may also have a vasodilating activity and would not be an acetylcholine-like substance in case it is same substance as that cause depressor responses.

• Journal of Microbiology and Biotechnology
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• 제30권11호
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• pp.1614-1625
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• 2020

A number of species of the genus Trichilia (Meliaceae) exhibit anti-inflammatory effects. However, the effect of Trichilia martiana C. DC. (TM) on lipopolysaccharide (LPS)-induced inflammation has not, to the best of our knowledge, yet been determined. Therefore, in the present study, the antiinflammatory effect of TM on LPS-stimulated RAW264.7 macrophages was evaluated. The ethanol extract of TM (TMEE) significantly inhibited LPS-induced nitric oxide (NO), prostaglandin 2 (PGE₂), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). TMEE also reduced the levels of inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β and IL-6. The upregulation of mitogen-activated protein kinases (MAPKs) and NF-κB activation was revealed to be downregulated following TMEE pretreatment. Furthermore, TMEE was indicated to lead to the nucleus translocation of nuclear factor erythroid-derived 2-related factor 2 (Nrf2) and the expression of heme oxygenase-1 (HO-1). In H292 airway epithelial cells, the pretreatment of TMEE significantly downregulated the production of LPS-stimulated IL-1β, and TMEE was indicated to increase the expression of HO-1. In animal models exhibiting LPS-induced acute lung injury (ALI), treatment with TMEE reduced the levels of macrophages influx and TNF-α production in the bronchoalveolar lavage fluid (BALF) of ALI mice. Additionally, TMEE significantly downregulated the activation of ERK, JNK and IκB, and upregulated the expression of HO-1 in the lungs of ALI mice. In conclusion, the results of the current study demonstrated that TMEE could exert a regulatory role in the prevention or treatment of the endotoxin-mediated inflammatory response.