• Toxicological Research
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• 제24권2호
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• pp.101-107
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• 2008

Studies on hypoxia-signaling pathways have revealed novel Fe(II) and $\alpha$-ketoglutarate-dependent dioxygenases that hydroxylate prolyl or asparaginyl residues of a transactivator, Hypoxia-Inducible $Factor-\alpha(HIF-\alpha)$ protein. The recognition of these unprecedented dioxygenases has led to open a new paradigm that the hydroxylation mediates an instant post-translational modification of a protein in response to the changes in cellular concentrations of oxygen, reducing agents, or $\alpha$-ketoglutarate. Activity of $HIF-\alpha$ is repressed by two hydroxylases. One is $HIF-\alpha$ specific prolyl-hydroxylases, referred as prolyl-hydroxylase domain(PHD). The other is $HIF-\alpha$ specific asparaginyl-hydroxylase, referred as factor-inhibiting HIF-1(FIH-1). The facts (i) that many dioxygenases commonly use molecular oxygen and reducing agents during detoxification of xenobiotics, (ii) that detoxification reaction produces radicals and reactive oxygen species, and (iii) that activities of both PHD and FIH-1 are regulated by the changes in the balance between oxygen species and reducing agents, imply the possibility that the activity of $HIF-\alpha$ can be increased during detoxification process. The importance of $HIF-\alpha$ in cancer and ischemic diseases has been emphasized since its target genes mediate various hypoxic responses including angiogenesis, erythropoiesis, glycolysis, pH balance, metastasis, invasion and cell survival. Therefore, activators of PHDs and FIH-1 can be potential anticancer drugs which could reduce the activity of HIF, whereas inhibitors, for preventing ischemic diseases. This review highlights these novel dioxygenases, PHDs and FIH-1 as specific target against not only cancers but also ischemic diseases.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2006년도 추계 학술발표회 발표논문집
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• pp.285-289
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• 2006

In screening of algicidal bacteria, we isolated a marine bacterium which had potent algicidal effects on harmful algal bloom (HAB) species. This organism was identified as a strain very close to Bacillus subtilisby 16S rRNA gene sequencing. This bacterium, Bacillus sp. SY-1, produces very active algicidal compounds against the harmful dinoflagellate Cochlodinium polykrikoides. We isolated three algicidal compounds (MS 1056, 1070, 1084) and identified them by amino acid analyses, fast atom bombardment mass spectrometry (FAB-MS), infrared spectroscopy (IR), $^1H$, $^{13}C$, and extensive two-dimensional nuclear magnetic resonance (2D NMR) techniques including $^1H-^{15}N$ HMBC analysis. One of them, MS 1056, contains a b-amino acid residue with an alkyl side chain of $C_{15}$. MS 1056, 1070, and 1084 showed algicidal activities against C. polykrikoides with an $LC_{50}$ (6 hrs) of 2.3, 0.8, $0.6\;{\mu}g/ml$, respectively. These compounds also showed significant algicidal activities against other harmful dinoflagellates and raphidophytes. In contrast, MS 1084 showed no significant growth inhibition against various organisms coexisting with HAB species in natural environments, including bacteria, eukaryotic microalgae, and cyanobacteria, although it inhibited growth of some fungi and yeasts. These observations imply that algicidal bacterium Bacillus sp. SY-1 and its algicidal compounds could play an important role in regulating the onset and development of HABs in the natural environments.

• Parasites, Hosts and Diseases
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• 제44권1호
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• pp.1-5
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• 2006

One coastal village in Haenam-gun and two in Yeongam-gun, Jeollanam-do were surveyed for intestinal parasite infections by fecal examination. The egg positive rates of Gymnophalloides seoi were high, $24.1\%$ (14/58) in Haenam-gun and $9.3\%$ (11/118) in Yeongam-gun. The egg positive rates of heterophyids, including Heterophyes nocens, and of Clonorchis sinensis were $10.3\%\;and\;6.9\%$ in Haenam-gun, and $14.4\%\;and\;8.5\%$ in Yeongam-gun, respectively. After praziquantel treatment and purgation, a total of 37,761 fluke specimens were recovered from 17 patients; 11 in Haenam-gun and 6 in Yeongam-gun. Gymnophalloides seoi was the most commonly recovered species, with 37,489 specimens in total (2,205 per person). Other recovered flukes included Heterophyes nocens, Stictodora fuscata, Heterophyopsis continua, Pygidiopsis sUmma, and undetermined species. These results indicate that the areas surveyed are new endemic foci of G. seoi.

• 대한수의학회지
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• 제24권2호
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• pp.201-211
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• 1984

개진드기 (Rhipicephalus sanguineus, Latreille 1806)는 세계적(世界的)으로 가장 넓은 분포(分布)를 보이는 종류(種類)로서 알려지고 있으나 지금까지 국내(國內)에서는 고 조사(調査)가 실시(實施)된 바 없다. 1981년(年) 부터 1984년年에 걸쳐 우리나라 가축(家畜) 진드기의 생능조사(生能調査) 및 방제대책(防除對策)에 연관(關聯)된 몇가지 시험(試驗) 연구사업(硏究事業)을 수행(遂行)하는 동안 경기(京畿), 충남(忠南), 전북(全北) 및 제주지역(濟州地域)의 목장(牧場)에서 사육(飼育)하고 있는 개와 부근의 초지(草地)로부터 미포혈(未飽血) 또는 부분(部分) 포혈(飽血)된 진드기 재료(材料)를 수집(採集)하여 조사(調査), 분류(分類), 정의(同定) 해 본 결과(結果), P. sanguineus로 확인(確認) 되었다. R. sanguineus의 국내(國內) 조사(調査)와 그 기록(記錄)과 더불어 수컷재료(材料)에 대(對)한 주사전자현미경(走査電子顯微鏡) (SEM) 영상촬영(映像撮影) 사진(寫眞)과 함께 형태학적특징(形態學的特徵)을 관찰(觀察)하여 보고(報告)한다. R. sanguineus의 국내(國內) 서식(棲息)이 확정(確定)됨에따라 총(總)8속(屬)(Argas, Amblyomma, Boophilus, Dermacentor, Haemaphysalis, Hyalomma, Ixodes, Rhipicephalus)의 진드기가 분포(分布)함이 밝혀졌다.

• 식물분류학회지
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• 제42권2호
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• pp.171-177
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• 2012

한반도 미기록식물인 Chaerophyllum tainturieri Hook. (산형과)와 Barbarea verna (Mill.) Asch. (십자화과) 2종을 서울과 부산에서 각각 발견하였다. 전호아재비로 이름붙인 C. tainturieri는 서울 상암동의 월드컵공원에서 확인되었다. Chaerophyllum속은 국내에서는 처음으로 본 연구에서 보고되는 미기록속이다. 형태적 유사종인 무산상자속(Sphallerocarpus Besser ex DC.) 식물과 비교하여 열매가 통모양이고, 분과의 갈라지는 틈에 1개의 유관이 있다는 특징으로 구별된다. 봄나도냉이로 이름붙인 Barbarea verna는 부산 금사동의 수영강 둔치에서 확인되었으며, 동속 식물인 나도냉이(B. orthoceras)와는 근생엽의 길이가 4-8 cm이고, 근생엽이 4-11쌍으로 갈라지며, 종자의 길이는 1-2 mm라는 특징으로 구별된다.

• 한국응용곤충학회지
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• 제35권2호
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• pp.153-158
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• 1996

국내산 41종과 79종 식물체 메탄올 추출물 및 일본산 1종 식물체 정유의 솔잎혹파리(Thecodiplosis japonensis Uchida et Inouye) 유충에 대한 살충황성을 여지접촉법과 충제침지법으로 조사한 결과 살추활성은 식물체 종류에 따라 달리 나타났다. 여지접촉법으로 여지당 시료 10mg을 처리하였을 때, 국내산 미나리아재비과의 지범, 부자의 위령선 뿌리 추출물과 일본산 측백나무과의 Thujopsis dolabrata var. hondai 톱밥의 정유가 90%이사의 살충활성을 보였다. 그러나 충제침지법(5,000ppm)을이용한 생물검정에서는 T.dolabrata var. hondai 톱밥의 정유만이 강한 살충활성을 나타내었다. 따라서 T.dolabrata var. Hondai 톱밥의 추출물의 솔잎 혹파리에의한 소나무림의 피해를 줄일 수 있을 것으로 생각된다.

• Bulletin of the Korean Chemical Society
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• 제21권10호
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• pp.969-972
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• 2000

[Fe II Fe III $BPLNP(OAc)_2](BPh_4)_2$ (1), a new model for the reduced form of the purple acid phosphatases, has been synthesized by using a dinucleating ligand, 2,6-bis[((2-pyridylmethyl)(6-methyl-2-pyridylmethyl)ami-no)methyl]-4-nitrophenol (HBPLNP) . Complex 1 has been studied by electronic spectral, NMR, EPR, SQUID, and electrochemical methods. Complex 1 exhibits two strong bands at 498 nm $(\varepsilon=$ 2.6 ${\times}10^3M-^1cm-^1)$ and 1363 nm $(\varepsilon=$ 5.7 ${\times}10^2M-^1cm-^1)$ in $CH_3CN.$ These are assigned to phenolate-to-FeIII and intervalence charge-transfer transitions, respectively. NMR spectrum of complex 1 exhibits sharp isotropically shifted resonances, which number is half of those expected for a valence-trapped species, indicating that electron transfer between FeⅡ and FeⅢ centers is faster than NMR time scale at room temperature. Complex 1 undergoes quasireversible one-electron redox processes. The $FeIII_2/FeIIFeIII$ and $FeIIFeIII/FeII_2$ redox couples are at 0.807 and 0.167 V ver-sus SCE, respectively. It has Kcomp = 5.9 ${\times}$10 1s(acetato) ligand combination sta-bilizes a mixed-valence FeIIFeIII complex in the air. Interestingly, complex 1 exhibits intense EPR signals at g = 8.56, 5.45, 4.30 corresponding to mononuclear high-spin FeⅢ species, which suggest a very weak magnetic coupling between the iron centers. Magnetic susceptibility study shows that there is a very weak antiferromag-netic coupling (J = $-0.78cm-^1$, H = $-2JS_1${\times}$S_2)$ between FeII and FeIII centers. Thus, we can suggest that complex 1 has a very weak antiferromagnetic coupling between the iron centers due to the electronic effect of the nitro group in the bridging phenolate ligand.

• Parasites, Hosts and Diseases
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• 제59권5호
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• pp.457-464
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• 2021

Cystic echinococcosis is a zoonotic parasitic disease caused by Echinococcus species. Tanzania is one of the endemic countries with cystic echinococcosis. This study focussed on identifying genotypes of Echinococcus spp. in Tanzania. We collected 7 cysts from cattle in Mwanza municipal (n=4) and Loliondo district (n=3). The cysts from Mwanza were all E. ortleppi and fertile. In contrast, the cysts from Loliondo were all E. granulosus sensu stricto and sterile. Two from the 4 cysts were a new haplotype of E. ortleppi (G5). These results can improve the preventive and control programs for humans and livestock in Tanzania. To our knowledge, this study is considered the first to identify the genotype and haplotype of Echinococcus spp. in Tanzania.

• International Journal of Industrial Entomology and Biomaterials
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• 제37권2호
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• pp.95-99
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• 2018

In insect defense system, antimicrobial peptides (AMPs) are one of important biological molecules to survive in a variety of environments. Insect can synthesize AMPs to protect against invading pathogens in humoral immune response. Taking more advantage of biological antimicrobial molecules, we report antibacterial activity of two cecropin type peptides, cecropin and moricin, isolated from the silkworm against four salmonella species. In this work, we purified antimicrobial candidate peptides (AMCP) from the extracts of immune challenged silkworm larval hemolymph by two-step chromatographic purification procedure, cation exchange and gel permeation chromatography. The molecular weights of purified peptides were estimated to be about 4 ~ 5 kDa by Tricin SDS-PAGE analysis, and identified as silkworm cecropin and moricin by NCBI BLAST homology search with their N-terminal amino acid sequences. As antibacterial activity assay, the purified peptides showed stronger antibacterial activity against Salmonella pathogens with an MIC value of $1{\sim}4{\mu}g/mL$. Therefore two cecropin type peptides purified from the silkworm will be valuable potential materials for development of new natural antibiotics.

• ALGAE
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• 제34권2호
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• pp.153-162
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• 2019

Anthropogenic disturbances, including coastal habitat modification and climate change are threatening the stability of kelp beds, one of the most diverse and productive marine ecosystems. To test the effect of temperature and irradiance on the microscopic gametophyte and juvenile sporophyte stages of the rare kelp, Saccharina angustissima, from Casco Bay, Maine, USA, we carried out two sets of experiments using a temperature gradient table. The first set of experiments combined temperatures between $7-18^{\circ}C$ with irradiance at 20, 40, and $80{\mu}mol\;photons\;m^{-2}\;s^{-1}$. The second set combined temperatures of $3-13^{\circ}C$ with irradiance of 10, 100, and $200{\mu}mol\;photons\;m^{-2}\;s^{-1}$. Over two separate 4-week trials, in 2014 and again in 2015, we monitored gametogenesis, the early growth stages of the gametophytes, and early sporophyte development of this kelp. Gametophytes grew best at temperatures of $8-13^{\circ}C$ at the lowest irradiance of $10-{\mu}mol\;photons\;m^{-2}\;s^{-1}$. Light had a significant effect on both male and female gametophyte growth only at the higher temperatures. Temperatures of $8-15^{\circ}C$ and irradiance levels of $10-100{\mu}mol\;photons\;m^{-2}\;s^{-1}$ were conditions for the highest sporophyte growth. Sporophyte and male gametophyte growth was reduced at both temperature extremes-the hottest and coldest temperatures tested. S. angustissima is a unique kelp species known only from a very narrow geographic region along the coast of Maine, USA. The coupling of global warming with high light intensity effects might pose stress on the early life-history stages of this kelp, although, as an intertidal species, it could also be better adapted to temperature and light extremes than its subtidal counterpart, Saccharina latissima.