• Title/Summary/Keyword: sp.

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Isolation and Characterization of the Marine Bacterium, Alteromonas sp. SR-14 Inhibiting the Growth of Diatom, Chaetoceros Species (규조류 Chaetoceros sp. 증식 저해균 Alteromonas sp. SR-14의 분리 및 특성)

  • KIM Ji Hoe;PARK Jeong Heum;SONG Young Hwan;CHANG Dong Suck
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.2
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    • pp.155-159
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    • 1999
  • Marine bacteria inhibiting the growth of the diatom, Chaetoceros calcitrans were screened from seawater samples collected at south coast of Korea in 1996. Six strains were isolated from those samples. Among them, a bacterium SR-14 strain had the strongest inhibition activity against the alga. The selected SR-14 strain was identified as an Alteromonas sp. (supposed to be Alteromonas colwelliana) according to its biochemical results. Alteromonas sp. SR-14 was able to grow in raw seawater, aged seawater, Conwy medium for culture of microalgae and C. calcitrans culture filtrate. The host ranges of Alteromonas sp. SR-14 were C. calcitrans, C. muclleri and C. negracile among 10 species of diatom. All of the Chaetoceros spp. tested were inhibited by the Alteromonas sp. SR-14, However, the growth of the other genera in Bacillariophyceae was not inhibited.

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Taxonomic Status of Acheilognathus sp. (Cyprinidae) found in the Geum River, Korea (금강에서 발견된 Acheilognathus sp. (Cyprinidae)의 분류학적 위치)

  • Chae, Byung Soo;Kim, Sang Ki;Lee, Jin Hee;Hwang, Ui Wook
    • Korean Journal of Ichthyology
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    • v.26 no.4
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    • pp.249-258
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    • 2014
  • To examine the taxonomic status of Acheilognathus sp. specimens from the Geum River, morphological and genetical characteristics of A. sp., A. yamatsutae and A. majusculus were investigated and compared in detail. Specimens of A. sp. could be distinguished from the other two species by the combination of some morphological characters such as nuptial color, vertebrae, gillrakers and etc. Males of A. sp. had red bands on the outer margin of dorsal and anal fins and a white band on the outer margin of ventral fin in breeding season. A. sp. had larger maximum body length and somewhat more vertebrae than A. yamatsutae, and had fewer gillrakers than A. majusculus. A. sp. appeared as a monophyletic group with A. majusculus and A. cyanostigma based on genetic analysis. In addition, it had even more close relationship with other congeners than A. yamatsutae. Therefore it is presumed that A. sp. from the Geum River may be a distinct species in genus Acheilognathus.

Dietary Value of Benthic Diatoms for Newly Settled Abalone, Haliotis discus hannai Ino (참전복 치패에 대한 부착성 규조류의 먹이효율)

  • 한형균;허성범
    • Journal of Aquaculture
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    • v.13 no.2
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    • pp.153-161
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    • 2000
  • Growth trends of 10 selected species of benthic diatoms, considered essential dietary requirement of the newly settled abalone were monitored. Navicula sp. (B-38), N. incerta and Caloneis schroderi, grew faster than the other tested diatoms. 16 and 32 % abalones fed on Raphoneis sp. and Phaeodactylum settled, respectively; less abalones souled, when fed on Navicula sp., Hantzxchia marina or Nitzschia sp. In the first experiment, survival of the settled abalone was the highest (63 %) and lowest (31 %) for those fed on Rhaphoneis sp. and Navicular sp. respectively. However, in the second and third series of esperiments, abalones fed on Rhaphoneis sp. and Navicula sp. showed the highest (67, 49 %) and lowest (35, 18 %) survival. C. schroderi proved to be the best diet, as the shell length of those fed on the diatoms was 83 ${\mu}$m, as against about 36 ${\mu}$m of those abalones, receiving H. marina or Nitzschia sp., diatoms of the lowest dietary value.

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The Distribution of Fish Larvae in the Korea Strait (대한해협의 자치어 분포상)

  • KIM Yong Uk
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.17 no.3
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    • pp.230-243
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    • 1984
  • Larvae of fishes were collected at 26 stations in the Korea Strait, by horizontal towings using the fish larval net (Norpac) in the surface layer and by oblique towings using Isaac-Kid mid-water trawl in the mid-water layer in summer (July) and in autumn (November), in 1983. The towing speed was 1.5 knots. Of the larval fish examined, 3,529 individuals were identified to generic and specific levels. They belong to 27 families, consisting of 38 species in 37 genera. Unidentified were 114 specimens. The most abundant species was Engraulis japonica which occupied $88.5\%$ of the whole 3,645 individuals. Diaphus sp. took the second place with 50 individuals ($l.3\%$). Seasonally abundant species were in the order of Engraulis japonica, a Gobid, Trichiurus lepturus, and Diaphus sp. in summer, and in the order of Diaphus sp., Engraxlis japonica, Bothus sp., and a Ophichthid in autumn. Of these larvae, Engraulis japonica and Diaphus sp. continuously appeared from summer to Autumn. Champsodon sp., Diaphus sp. and Synagrops philippinensis were unrecorded species in Korea.

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Effect of pH on Growth and Cultural Characteristics of Bacillus sp. SH-8 and Bacillus sp. SH-8M (Bacillus sp. SH-8과 Bacillus sp. SH-8M의 생육 및 배양 특성에 미치는 pH의 영향)

  • 심창환;신원철;유주현
    • Microbiology and Biotechnology Letters
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    • v.20 no.4
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    • pp.371-376
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    • 1992
  • The growth and cultural characteristics of Bacillus sp. SH-8 and SH-8M were investigated at various pH conditions. Bacillus sp. SH-8 showed normal growth pattern above pH 9.0. However, with the pH adjusted below 7.7, 0.$D_{550}$ decreased rapidly with concomitant reduction in viable cell numbers. In contrast, Bacillus sp. SH-8M demonstrated growth capability at pH 7.7, but with slightly reduced growth rate at pH 6.9. Similar results were obtained when those two strains were cultivated on the solid medium. Both of them showed short rod shapes at pH 10.2. However, at pH 7.7 only Bacillus sp. SH-8 was observed to have elongated rod shape. Extracellular pH of both the strains, when cultured at initial pH of 10.2, reached to 9.0 after the incubation of 28 hours. At the initial pH of 9.0 and 9.6, the extracellular pH was reduced at the beginning of cultivation, but elevated after 12 hours. When cultured at initial pH of 6.9 and 7.7, extracelluar pH of Bacillus sp. SH-8M increased to 8.0 and 8.7, respectively, while that of Bacillus sp. SH8 remained constant pH 7.0. The highest sporulation rate of Bacillus sp. SH-8 and SH-8M was obtained at the initial pH of 10.2 and after the incubation of 3 days with the sporulation rate of 95% and 85%, respectively.

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The Effect of Dexamethasone on Gene Expression and Total Amount of Surfactant Protein A (스테로이드제가 Surfactant Protein A의 유전자 발현과 총단백량에 미치는 영향에 관한 실험적 연구)

  • Lim, Byung Sung;Sohn, Jang Won;Yang, Seok Chul;Yoon, Ho Joo;Shin, Dong Ho;Park, Sung Soo
    • Tuberculosis and Respiratory Diseases
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    • v.52 no.4
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    • pp.395-404
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    • 2002
  • Background : Surfactant protein A (SP-A) is important for regulating surfactant secretion, synthesis and recycling. However, It's regulation in vivo is unclear. SP-A has important roles in regulating surfactant metabolism as well as determining its physical properties. Glucocorticoid accelerates the morphologic differentiation of epithelial cells into type II cells and increase the rate of phosphatidylcholine synthesis. Methods : The authors investigated the effects of glucocorticoid on the accumulation of mRNA encoding SP-A and SP-A protein content. Adult rats were given various doses of subcutaneous dexamethasone and sacrificed after 24 hours and one week. SP-A mRNA was measured using a filter hybridization method. The lung SP-A protein content was determined using a double sandwich ELISA assay with polyclonal antiserum raised in rabbits against purified rat SP-A. Results : 1) The accumulation of SP-A mRNA in the dexamethasone treated group 24 hours after 0.2 mg/kg dexamethasone treatment was increased 38.8% compared to the control group. 2) The accumulation of SP-A mRNA in the dexamethasone treated group 1 week after 2 mg/kg dexamethasone treatment was 49.7% higher than the control group(P<0.01). 3) The total lung SP-A level was not altered after 24 hours by the 0.2mg/kg treatment. The total lung SP-A content one week after 2mg/kg dexamethasone administration was 373.7% higher than the control group(P<0.005). Conclusion : Dexamethasone treatment results in an increase in the SP-A mRNA and SP-A protein levels, suggesting that the pretranslational events in vivo may in part contribute to this process.

Gene Expression of Surfactant Protein B and C in Endotoxin and Thiourea Treated Rats (내독소 및 Thiourea 투여 후 Surfactant protein B와 C 유전자 발현의 비교 관찰)

  • Sohn, Dong Hyun;Sohn, Jang Won;Yoon, Ho Joo;Shin, Dong Ho;Park, Sung Soo
    • Tuberculosis and Respiratory Diseases
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    • v.54 no.5
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    • pp.510-521
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    • 2003
  • Background : The surfactant specific proteins, SP-B and SP-C are believed to be important regulators of the surfactant function and homeostasis. Since acute respiratory distress syndrome(ARDS) is usually viewed as the functional and morphological expression of a similar underlying lung injury caused by a variety of insults, and since abnormalities in the surfactant function have been described in ARDS, the authors investigated the different effects of endotoxin and thiourea on the accumulation of mRNA encoding SP-B and SP-C. Methods : Sprague-Dawley rats were given 5 mg/kg of an intraperitoneal endotoxin from Salmonella enteritidis and 3.5 mg/kg intraperitoneal thiourea and were sacrificed at different time periods. Results : 1. The SP-B mRNA levels 6 and 24 hours after the 5 mg/kg endotoxin treatment was significantly reduced by 26.1% and 50%, respectively(P<0.01, P<0.001). 2. The SP-B mRNA levels 24 hours after the 3.5 mg/kg thiourea treatment was reduced by 9.8% and 12.5%, respectively. 3. The SP-C mRNA levels 6 and 24 hours after the 5 mg/kg endotoxin treatment was significantly reduced by 38.7% and 53.6%, respectively(P<0.01, P<0.001). 4. The SP-C mRNA level 6 hours after the 3.5 mg/kg thiourea treatment was reduced by 22.8%(P<0.05). Conclusion : These results indicate that the differential regulation of the hydrophobic surfactant proteins in vivo is evident, and suggest that the hydrophobic surfactant proteins might be differentially regulated during lung injury at different time periods without altering the lung wet to dry ratios. The mechanism of these alternations at the different time periods and the different kinds of etiology remain to be determined.

Ecological Studies on the Causative Agents of Food Poisoning from Food Animals - 1. Patterns on the Outbreaks and Antimicrobial Susceptibility of Causative Agents Isolated from Bovine Mastiffs in a Rural Area (축산유래 식중독 세균에 관한 생태학적 연구 제1보 : 일부 농촌지역 젖소 유방염의 발생양상 및 그 원인균이 항균요법제에 관한 감수성)

  • 정희곤
    • Journal of Environmental Health Sciences
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    • v.20 no.2
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    • pp.90-98
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    • 1994
  • Introduction : Bovine mastitis is an economically and a hygienically important disease of dairy cows. Many factors predispose to bovine mastitis and an understanding of these is essential for systems of effective mastiris control to be formulated. The presence of non-pathogenic bacteria on body surfaces can protect against invasion by more pathogenic organisms. Bacteria of low pathogenicity (minor pathogens) are frequently isolated from the healthy bovine udder and may play an important role in protecting the udder from infection with pathogenic bacteria. The treatment of bovine mastitis is important for choosing adequate antimicrobias, and it take the base on the result of susceptibility to antimicrobias. Therefore, the current of numbers feeding dairy cattle were increasing and prevalence rate of bovine mastiris was occurred in 1.5~57.3%.(abbreviation)

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Morphological Studies of the Central Neural Pathways to the Pancreas, Sanyinjiao(Sp6) and Yinlingquan(Sp9) using Pseudorabies Virus (Pseudorabies virus를 이용한 췌장과 삼음교(三陰交)(Sp6), 음릉천(陰陵泉)(Sp9)에서 투사되는 중추 신경로에 관한 형태학적 연구)

  • Kim, Cheol-Han;Lee, Su-Kyung;Yeom, Seung-Ryong;Kwon, Young-Dal;Song, Yung-Sun
    • Journal of Korean Medicine Rehabilitation
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    • v.19 no.1
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    • pp.23-38
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    • 2009
  • Objectives : The purpose of this morphological studies was to investigate the relations between Sanyinjiao(Sp6), Yinlingquan(Sp9) and pancreas of rats using peudorabies virus(PRV). Methods : We observed labeled neurons following the injection of PRV, Bartha strain, into the Sanyinjiao(Sp6), Yinlingquan(Sp9) and pancreas of rats. After survival times of 4 days following the injection of PRV, the rats were perfused, and their spinal ganglia, spinal cord and brain stem were frozen sectioned($35{\mu}m$). These sections were strained by PRV immunohistchemical staining methods and observed with light microscope. Results : The results were as follows. 1. In the spinal ganglia, the overlap areas of PRV labeled neurons projecting to Sanyinjiao(Sp6), Yinlingquan(Sp9) and pancreas were observed in T10-13 dorsal root ganglia. 2. In the spinal cord, the overlap areas of PRV labeled neurons projecting to Sanyinjiao(Sp6), Yinlingquan(Sp9) and pancreas were lamina I, IV, V, VII, IX, X, intermediolateral nucleus(IML), intermediomedial nucleus(IMM) in thoracic segments. In lumbar segments, the overlap areas of PRV labeled neuron were lamina I, IV, V, VI, IX, X and IMM. In sacral segments, the overlap areas of PRV labeled neuron were lamina I, IV, V, VI, VII, IX, X. 3. In the brain, the overlap areas of PRV labeled neurons projecting to Sanyinjiao(Sp6), Yinlingquan(Sp9) and pancreas were area postrema, nucleus tractus solitarius, caudoventrolateral reticular nu., medullary reticular nu., lateral paragigantocellular nu., C3 adrenalin cells, gigantocellular nu., raphe pallidus nu., raphe obscurus nu., ambiguus nu., raphe magnus nu., pontine reticular formation, A5 cell group, subcoeruleus nu., locus coeruleus, Barringnton's nu., $K{\ddot{o}}lliker$-Fuse nu., dorsal raphe nu., Edinger-Westphal nu., central gray matter, perifornical nu., dorsomedial hypothalamic nu., arcuate nu., lateral hypothalamic nu., paraventricular hypothalamic nu., hindlimb area. Conclusions : In conclusion, these results suggest that the interrelationship of meridian(spleen meridian), acupoints(Sp6 and Sp9) and viscera(pancreas) may be related the central autonomic centers.

Parasites of Freshwater Fishes in Cheju-do (제주도산(濟州道産) 담수어류(淡水魚類)에 기생(寄生)하는 기생충(寄生蟲)에 관한 연구(硏究))

  • Jo, Jae-Yoon
    • Journal of fish pathology
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    • v.3 no.2
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    • pp.51-60
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    • 1990
  • Parasites of freshwater fishes in Cheju-do were studied from May 1989 to April 1990, and incidence of infection in 16 fish species was reported. Protozoan parasites (Trichodina sp., Chilodonella sp., Ichthyophthirius sp., Vorticella sp., Myxidium sp., Myxobolus sp., Henneguya sp:, Ichthyobodo sp., and Trychophrya sp.), water mold (Saproregnia sp.), two monogenes (Dactylogyrus sp. and Gyrodactylogyrus sp.), Trematods, Cestods, Nematods, Acanthocephalas, parasitic copepods(Lernaea sp. and Pseudergasilus sp.) and a Hirudinea were recognized as freshwater fish parasites in Cheju-do. Trichodina sp. showed the highest infection rate (18.3%). Fifty seven individual fishes out of 311 were infected by this parasite. Nematods showed the second highest infection rate (13.5%). Dactylogyrus sp., Acanthocephalas, and Trematods showed the third (4.8%), fourth (4.2%), and fifth (2.6%) infection rate respectively. Of the 16 fish species Cryptocentrus filifer (Gobiidae) showed the highest infection rate. Nineteen fish out of 28 have Trichodina sp., and 14 fish out of 28 have Nematods. Those infection rates were 67.9% and 50.0% respectively. No parasites were collected from the fishes of Gwangryung vally, Dosoon-chun, Gangjeong-chun, and Hyodon-chun.

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