• Title/Summary/Keyword: Tropical conditions

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Studies on the Current Epidemiological Situation of Brugian Filariasis in Endemic Areas of Korea (최근 국내 사상충증의 역학적 상황에 관한 조사)

  • 백영한;조유정
    • Parasites, Hosts and Diseases
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    • v.26 no.4
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    • pp.255-262
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    • 1988
  • An epidemiological study on brugian filariasis was carried out in endemic areas including Cheju Island in Korea, with a brief review of literatures. The results showed that the incidence among residents has remarkably decreased in Cheju Island, which was the main endemic area. Reviewing available informations on the prevalence of filariasis reported in recent years and also judging from the present socio·economic conditions which enable people to practice personal protection against mosquitos, it can be said with confidence that alariasis has almost disappeared from Cheju Island and inland areas. The disease is considered to remain at a low level of endemicity in Hugsan Islands. Certainly mass diethylcarbamasine (DEC) treatment carried out in Cheju Island in the 1960s and 1970s and remarkable economic growth followed by improved living standard and altered life-style of inhabitants could all have combined effects on the disappearance of this mosquito-borne disease in this island. If the present trends go on, the possibility of resurgence of filariasis in Cheju Island is hardly postulated.

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Characterization of proteases of Toxoplasma gondii (Toxoplasma gondii에서 단백질 분해 효소의 특징)

  • Choe, Won-Yeong;Nam, Ho-U;Yun, Ji-Hye
    • Parasites, Hosts and Diseases
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    • v.27 no.3
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    • pp.161-170
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    • 1989
  • The proteases of Toxoplasma gcndii were purified partially and characterisrd for some biochemical properties including various chromatographic patterns, major catalytic classes, and conditions to promote the activity of these enzymes. When Toxoplasma extract was incubated with 3H-casein at various pH, peak hydrolysis of casein was observed at pH 6.0 and at pH 8.5. Proteasfs working at pH 6.0 and at pH 8.5 were purified partially by conventional methods of chromatographies of DE52 anion rxchange, Sephadex G-200 gel permeation, and hydroxylapatite chromatography. Partially purified enzymes were tested by site-specific inhibitors and promotorf. The protease working at pH 6.0 was inactivated by iodoacetamide with LDso of 10-5 M and promoted by dithiothreitol, while the protease working at pH 8.5 was inhibited by phenylmethylsulfonyl fluoride with LD50 of 10-5 M and was Promoted by ATP (excess ATP beyond 2 mM inhibited the activity reversely). The protease of pH 8.5 had the activity of ATPase which might exert the energy to its action. Therefore the former was referred to as a cysteinyl acid protease and the latter, ATP-dependent neutral serine protease.

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Immunoblot observation of antigenic protein fractions in Paragonimus tvestermani reacting with humall patients sera (폐흡충 항원단백질에 대한 폐흠충증 한자 혈청의 반응 양상)

  • Kim, Sung-Hwan;Kong, Yoon;Kim, Suk-Il;Kang, Shin-Yong;Cho, Seung-Yull
    • Parasites, Hosts and Diseases
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    • v.26 no.4
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    • pp.239-244
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    • 1988
  • In order to observe the antigenic fractions in saline extract of adult Paragonimus westermani, proteins in the crude extract were separated by sodium dodecyl sulfate-polyacylamide gel electrophoresis(SDS.PAGE) in reducing conditions. The separated protein fractions were transferred to nitrocellulose paper on which 20 sera from human paragonimiasis were reacted and immunoblottrd. Out of 15 stained protein bands in SDS-PAGE, 7 reacted with infected sera while 8 did not. Additionally, 7 unstained protein bands in SDS-PAGE reacted with the sera. Of 14 reacted bands, 30 kilodalton(kDa) band was the most frequently reacted (95%) and was a strong antigen. Protein bands of 23 and 46 kDa were also strong antigens. Bands of over 150 kDa, 120 kDa, 92 kDa, 86 kDa, 74 kDa, 62 kDa, 51 kDa, 32 kDa, 28 kDa, 16.5 kDa and 15.5 kDa were also reactive but their frequencies of the reaction were variable. Key words: Paragonimus westermani, human paragonimiasis, antigenic proteins, SDS-PAGE/ immunoblot

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Stratigraphy and Paleoceanography of deep-sea core sediments from the Korea Deep Ocean Study (KODOS)-97 Area, Northeast Equatorial Pacific (북동태평양 KODOS-97지역 주상 퇴적물의 층서 및 고해양학적 연구)

  • Park, Jeong-Hee;Kim, Ki-Hyune
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.4 no.1
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    • pp.50-62
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    • 1999
  • Sediment core samples recovered from the Korea Deep Ocean Study (KODOS)-97 area were divided into two or three units according to their distinct changes in sediment colors and chemical and physical properties. Analyses of radiolarian faunas in the sediments and $^{10}Be$ ratios in each unit were performed to reveal stratigraphic and paleoceanographic history of the study area. In the upper part of the sediments, Tertiary radiolarians were mixed at various proportions with Quaternary assemblages probably by reworking process of bottom current and benthic animals. Dissolution of radiolarians was severe in deeper depth and in the Unit III, only few of the fragments of corroded Tertiary radiolarians were detectable. The mid layer of the Unit I belonged to Collosphaera invaginata Zone, the time period of 0.21 Ma. The Unit II belonged to Collosphaera tuberosa Zone with the time period younger than 0.42 Ma which was observed above the Stylatractus universus Zone. The Unit III is assigned to Tertiary, which is younger than the Late Eocene. Composition analyses of radiolarian assemblage and $^{10}Be$ ratio data indicated hiatus periods of more than 3 My between late of Middle Miocene and Pliocene resulting from erosion and dissolution caused by Antarctic Bottom Water. Stratigraphic evidence from radiolaria was well correlated with $^{10}Be$ data. Sedimentation rate during Quaternary can be suggested as 0.15-0.5 mm per 1000 years. Dominance of warm-water radiolaria species and the results reflected minimum climatic changes of tropical conditions.

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Studies on the Prevention of Greening in Crushed Garlic from Bulbs Stored in Low Temperature (마늘의 저온저장후 파쇄마늘 제조시 발생하는 녹변방지 연구)

  • Choi, Sun-Tay;Lim, Byung-Seon;Mok, Il-Gin;Lee, Chong-Suk;Chang, Kyu-Seob
    • Food Science and Preservation
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    • v.7 no.3
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    • pp.245-248
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    • 2000
  • It was attempted to find a method to prevent greening of crushed garlic. The storage conditions and heat treatments before crushing were tested for the prevention of greening in crushed garlic. 'Namhae' garlic (sub-tropical type), 'Seosan' and 'Danyang' garlic (traditional) type for cool area) were stored in room temperature(20${\pm}5^{\circ}C$, low temperature(0$^{\circ}C$), and CA(O$_2\;3%,\;CO_2$ 5%) storage for five months, and their samples were crushed. The crushed garlic had no significant differences in greening according to the cultivars. Greening did not occur for the crushed garlic from bulbs stored either in room temperature or CA storage. Greening was the unique symptom observed in crushed garlic from bulbs stored in low temperature. For the prevention of greening, heat treatment was conducted at 40, 35 and 30$^{\circ}C$ prior to make the crushed garlic from bulbs which were stored in low temperature. The effective duration of heat treatment before crushing was 7 days at 30$^{\circ}C$, 3 days at 35$^{\circ}C$, and 1 days at 40$^{\circ}C$ Greening was most effectively prevented in 1 day at 40$^{\circ}C$ treatment. During the heat treatments, changes in enzymatic pyruvic acid content and sprouting rate were slightly observed in garlic bulbs treated at 40$^{\circ}C$ for 1 day.

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Chemical Weathering Trend and Rubefaction of Granitic Hills in Naju, Southern Korea (한반도 남서부 나주 일대 화강암 구릉대의 적색화와 화학적 풍화 경향)

  • Kim, Young Rae
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.1
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    • pp.57-68
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    • 2012
  • Red saprolites are appeared in granitic hills in Naju, Southern Korean Peninsula. These red saprolites were analyzed for their geochemistry, including CIA, A-CN-K and A-CNK-FM ternary plots, to understand the chemical weathering trend and rubefaction of the saprolites. These saprolites were compared with kaolinitic saprolites of Guadalquivir Basin in Spain formed under paleo-humid tropical conditions. Chemical Index of Alteration(CIA) value for Naju in Korea is 80, and 87 in Guadalquivir, suggesting moderate and strong weathering in both. Relative to kaolinitic saprolite of Guadalquivir in Spain, red saprolites in Naju are commonly weak loss of CaO, $Na_2O$, especially in $K_2O$. The A-CNK-FM ternary plots of Naju saprolites relative to Kaolinitic saprolites of Guadalquivir shows weak chemical alteration owing to slow removal of $K_2O$, but high mafic constituents, $Fe_2O_3$ and MgO, for most of the samples. In the saprolites of Naju, mafic oxides, $Fe_2O_3$ and MgO, become enriched because of the fast and massive removal of CaO, $Na_2O$ and $K_2O$ relative to other elements, resulting in rubefaction of the surface layer of the saprolites, so more redness than kaolinitic saprolites of Guadalquivir. It is found that the rubefaction of the saprolites is not necessarily proportional to chemical weathering intensity.

QTL Analysis of Germination Rate and Germination Coefficient of Velocity under Low Temperature in Rice (저온에서 벼의 발아율 및 발아속도 관련 양적형질 유전자좌(QTL) 분석)

  • Kim, Jinhee;Mo, Youngjun;Ha, Su-Kyung;Jeung, Ji-Ung;Jeong, Jong-Min
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.66 no.1
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    • pp.8-17
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    • 2021
  • As rice originates from tropical regions, low temperature stress during the germination stage in temperate regions leads to serious problems inhibiting germination and seedling establishment. Identifying and characterizing quantitative trait loci (QTLs) for low-temperature germination (LTG) resistance help accelerate the development of rice cultivars with LTG tolerance. In this study, we identified QTLs for LTG tolerance (qLTG5, qLTG9) and germination coefficient of velocity under optimal conditions (OGCV) (qOGCV7, qOGCV9) using 129 recombinant inbred lines (RILs) derived from the cross between a low-temperature sensitive line Milyang23 and a low-temperature tolerant variety Gihobyeo. qLTG9 and qOGCV9 were detected at the same location on chromosome 9. At both LTG QTLs (qLTG5 and qLTG9), the alleles for LTG tolerance were contributed by the japonica variety Gihobyeo. At qOGCV7 and qOGCV9, the alleles for low temperature tolerance were derived from Milyang23 and Gihobyeo, respectively. The RILs with desirable alleles at two or more QTLs, i.e., GroupVII: qLTG5+qLTG9 (qOGCV9) and GroupVIII: qLTG5+qOGCV7+qLTG9 (qOGCV9), showed stable tolerance under low-temperature stress. Our results are expected to contribute to the improvement of tolerance to low-temperature and anaerobic stress in japonica rice, which would lead to the wide adoption of direct-seeding practices.

Ginsenoside Ro, an oleanolic saponin of Panax ginseng, exerts anti-inflammatory effect by direct inhibiting toll like receptor 4 signaling pathway

  • Xu, Hong-Lin;Chen, Guang-Hong;Wu, Yu-Ting;Xie, Ling-Peng;Tan, Zhang-Bin;Liu, Bin;Fan, Hui-Jie;Chen, Hong-Mei;Huang, Gui-Qiong;Liu, Min;Zhou, Ying-Chun
    • Journal of Ginseng Research
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    • v.46 no.1
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    • pp.156-166
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    • 2022
  • Background: Panax ginseng Meyer (P. ginseng), a herb distributed in Korea, China and Japan, exerts benefits on diverse inflammatory conditions. However, the underlying mechanism and active ingredients remains largely unclear. Herein, we aimed to explore the active ingredients of P. ginseng against inflammation and elucidate underlying mechanisms. Methods: Inflammation model was constructed by lipopolysaccharide (LPS) in C57BL/6 mice and RAW264.7 macrophages. Molecular docking, molecular dynamics, surface plasmon resonance imaging (SPRi) and immunofluorescence were utilized to predict active component. Results: P. ginseng significantly inhibited LPS-induced lung injury and the expression of proinflammatory factors, including TNF-α, IL-6 and IL-1β. Additionally, P. ginseng blocked fluorescencelabeled LPS (LPS488) binding to the membranes of RAW264.7 macrophages, the phosphorylation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs). Furthermore, molecular docking demonstrated that ginsenoside Ro (GRo) docked into the LPS binding site of toll like receptor 4 (TLR4)/myeloid differentiation factor 2 (MD2) complex. Molecular dynamic simulations showed that the MD2-GRo binding conformation was stable. SPRi demonstrated an excellent interaction between TLR4/ MD2 complex and GRo (KD value of 1.16 × 10-9 M). GRo significantly inhibited LPS488 binding to cell membranes. Further studies showed that GRo markedly suppressed LPS-triggered lung injury, the transcription and secretion levels of TNF-α, IL-6 and IL-1β. Moreover, the phosphorylation of NF-κB and MAPKs as well as the p65 subunit nuclear translocation were inhibited by GRo dose-dependently. Conclusion: Our results suggest that GRo exerts anti-inflammation actions by direct inhibition of TLR4 signaling pathway.

Native Hawaiian Collection Systems in Lava Tubes(Caves) and Fault Cracks: Puna - Ka'u Districts, Hawaii

  • Martin, James F.
    • Journal of the speleological society of Korea
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    • no.4
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    • pp.41-50
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    • 1996
  • The coastal plains of the Puna and Ka' u Districts of the island of Hawaii are a contradiction to the popular view that the island of Hawaii is a tropical rain forest or a vegetated landscape with abundant water sour This section of the island lies in the rain shadow of Mauna Loa a Kilauea Volcanoes and receives less than 30 inches of annual precipita When rain does come. it is in the form of sudden down pours. givi residents of the area little time to collect and conserve water. Due to porous nature of the rock. there is no standing surface water. In spite of these harsh climatic conditions. archeological evidence indic that an extensive agriculture complex existed not only along the coast. into the most remote parts of what is called the Ka'u Desert. Pass through these agricultural areas are historic and pre - historic t systems. These trail systems apparently played a significant suppor role for exchange between the ahupua's (classic land divisions of Haw and the geopolitical districts. The question arises as to how could vast agricultural complexes a heavy foot travel over miles of arid land exist without dependable wa sources\ulcorner While planting - pits and mounds were designed to make most efficient use of available water and conserve moisture(Carter 19 9). people involved in planting also needed potable water for surv Most publications and research papers dealing with the early population this area make only oblique reference to springs and wells which t populations depended upon. The Federal Cave Resource Protection Act(1988) has served as imprtus for the National Park Service to look closer at the lava tu caves and fault cracks within Hawaii Volcanoes National Park. P visitors to these underground areas found large volumes of standing wa in fault cracks. and abundant drip areas with the lava tubes. Re observes noted that in most cases. where the cracks and caves we located in the arid sections of the park. there has been extens modifiacation or utilization of these water sources by the early Hawaii and others. The variety of western containers used for collection indica that these water sources were used during historic times. William E described similar water sources in his narrative of his trip around island in 1823(Eills 1979), This report is directed at documenting recent observations and a stimulating further research into early Hawaiian water collection syst It also explores the implications that power and political influence of e chiefs in the arid portions of Hawaii could have been linked to the con of the water resources.

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Studies on the Seedling Production of the Freshwater Crab, Eriocheir japonicus (De Haan) 1. Reproductive Ecology (동남참게, Eriocheir japonicus (De Haan)의 종묘생산에 관한 생물학적 기초연구 1. 번식생태)

  • KWON Chin-Soo;LEE Bok-Kyu;LEE Chae-Sung
    • Journal of Aquaculture
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    • v.6 no.4
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    • pp.235-253
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    • 1993
  • The freshwater crab, Eriocheir japonicus inhabits from sub-tropical to temperate zone in Asia. This species belongs to a large size group among freshwater crabs. Common size of this crab is 5-6cm in carapace length and occasionally 7cm in carapace length. This species of crab used to inhabit in estuaries, rivers and inland waters in Korea. However, natural population recently has been rapidly decreased because of pollution and lost their habitats by suburban development. Therefore, development of proper methods of seedling production to increase natural stock became necessity. As parts of achieving this goal, duration from mating to spawning, egg incubation period, and egg development of this species were studied. The influence of temperatures and salinities on the egg incubation and hatching was also investigated. It took 2-8 hours from mating to egg spawning and the spawning lasted 3-9 hours from the first spawning. Egg numbers per female (6cm in carapace length) were 380,000­410,000. Optimum temperature for egg incubation was $17\~23^{\circ}C$ and optimum salinity, $14.0\~31.5\%o$. Incubation period of the eggs at $14^{\circ}C,\;17^{\circ}C,\;20^{\circ}C,\;26^{\circ}C,\;and\;28^{\circ}C$ was 42, 28, 21, 15, and 14 days. respectively. Relation between temperature (X) and incubation days (Y) was LogY = Log 2764.267 - 1.608 LogX. A female can spawn 4-6 times per year by manipulation of environmental conditions. Under the conditions of $18^{\circ}C\;and\;24.5\%o$, it took 6 days up to embryo formation, 18 days up to compound eye formation, 22 days up to abdominal movement, and 25 days up to hatch out as zoea larvae.

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