• Asian Pacific Journal of Cancer Prevention
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• 제15권11호
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• pp.4519-4525
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• 2014

Oleanolic acid (OA) is a nutritional component widely distributed in various vegetables. Although it has been well recognized for decades that OA exerts certain anti-tumor activity by inducing mitochondria-dependent apoptosis, it is still unclear that what molecular signaling is responsible for this effect. In this study, we employed cancer cell lines, A549, BXPC-3, PANC-1 and U2OS to elucidate the molecular mechanisms underlying OA anti-tumor activity. We found that activation of MAPK pathways, including p-38 MAPK, JNK and ERK, was triggered by OA in both a dose and time-dependent fashion in all the tested cancer cells. Activation was accompanied by cleavage of caspases and PARP as well as cytochrome C release. SB203580 (p38 MAPK inhibitor), but not SP600125 (JNK inhibitor) and U0126 (ERK inhibitor), rescued the pro-apoptotic effect of OA on A549 and BXPC-3 cells. OA induced p38 MAPK activation promoted mitochondrial translocation of Bax and Bim, and inhibited Bcl-2 function by enhancing their phosphorylation. OA can induce reactive oxygen species (ROS)-dependent ASK1 activation, and this event was indispensable for p38 MAPK-dependent apoptosis in cancer cells. In vivo, p38 MAPK knockdown A549 tumors proved resistant to the growth-inhibitory effect of OA. Collectively, we elucidated that activation of ROS/ASK1/p38 MAPK pathways is responsible for the apoptosis stimulated by OA in cancer cells. Our finding can contribute to a better understanding of molecular mechanisms underlying the antitumor activity of nutritional components.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6773-6779
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• 2014

Background: Nanotechnology opens new applications in many fields including medicine. Among all metallic nanoparticles, silver nanoparticles (silver NPS) have proved to be the most effective against a large variety of organisms including toxic cyanobacteria. Materials and Methods: Silver NPs were biosynthesized in vivo with different alga species namely, Spirulina piatensis, Chlorella vulgaris and Scenedesmus oh/iquus following two scenarios. First: by suspending a thoroughly washed algae biomass in 1 mM aqueous $AgN0_3$ solution. Second: by culturing them individually in culture media containing the same concentration of $AgN0_3$. Silver NPs were characterized using UV-Vis spectroscopy, transmission electron microscopy (TEM), energy dispersive analysis (EDX) and Fourier transform infra-red (FfIR) spectroscopy. The biosynthesized silver NPs were tested for cytotoxic activity against a cancer promoter cyanobacteruim Microcystis aeruginosa, considering effects on cell viability and chlorophyll content. Results: The surface plasmon band indicated the biosynthesis of silver NPs at ~400 nm. Transmission electron microscopy (TEM) revealed that the silver NPs had a mean average size below 100 nm. Energy-dispersive analysis X-ray (EDX) spectra confirmed the presence of silver element. FfIR spectral analyses suggested that proteins and or polysaccharides may be responsible for the biosynthesis of silver NPs and (-COO-) of carboxylate ions is responsible for stabilizing them. The toxic potentialities ofthe biosynthesized silver NPs against the cancer promoter cyanobacterium, Microcystis aeruginosa showed high reduction in viable cells count and the total chlorophyll content. Conclusions: The potential activity of the biosynthesized silver NPs from the studied algae species against Microcystis aernginosa cells is expected to be mainly mediated by the release of silver ions (Ag+) from the particle surface and bioactive compounds as indicated by FfIR analysis.

• 한국수산과학회지
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• 제47권1호
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• pp.18-22
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• 2014

The antibacterial activities of methanol extracts of 19 commercial herbal medicines were measured against the fish pathogens Vibrio ichthyoenteri and Streptococcus iniae, which cause several fish diseases. Rhus javanica showed the strongest antibacterial activity against V. ichthyoenteri and S. iniae. The methanol extract of R. javanica was extracted further using several organic solvents with different polarities. The extract from the ethyl acetate fraction showed strong activity against both fish pathogens. The minimum inhibitory concentration (MIC) of the R. javanica extract was $32{\mu}g/mL$ for V. ichthyoenteri and $128{\mu}g/mL$ for S. iniae. Further purification and isolation of the active compound (s) responsible for these activities and further study of the synergistic effect using combinations of antibiotics against pathogenic bacteria are needed.

• 한국수산과학회지
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• 제47권3호
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• pp.247-254
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• 2014

To investigate the acquisition of quinolone resistance, we examined mutations in the quinolone resistance-determining region (QRDR) of type II topoisomerase genes in ciprofloxacin (CIP)-resistant clinical isolates and in vitro mutants of Streptococcus parauberis. The CIP-resistant clinical isolates had one base change responsible for a Ser-79${\rightarrow}$Thr in the QRDR of parC. However, the CIP-resistant in vitro mutants had an altered QRDR of parC (Ser-79${\rightarrow}$Ile) that differed from that of the isolates. None of the CIP-resistant S. parauberis clinical isolates or in vitro mutants exhibited amino acid changes in gyrA or gyrB. However, even though involvement in the increased resistance was not clear, an Arg-449${\rightarrow}$Ser mutation outside of the QRDR of parE was detected in CIP-resistant mutant 2P1. These results suggest that the topoisomerase IV gene, parC (and possibly parE, as well), is the primary ciprofloxacin target in S. parauberis. Additionally we established a high-resolution melting (HRM) assay capable of detecting the dominant mutation in four type II topoisomerase genes conferring ciprofloxacin resistance. These rapid and reliable assays may provide a convenient method of surveillance for genetic mutations conferring antibiotic resistance.

• 한국수산과학회지
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• 제49권5호
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• pp.678-682
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• 2016

Antibacterial activity of 80% methanol extract from 13 commercial herb medicines was measured against fish pathogens Streptococcus iniae, causing several diseases in various kind of fish. Siegesbeckia pubescens showed the strongest antibacterial activity against S. iniae. Methanol extract of S. pubescens was further extracted using several organic solvents having different polarity. Extract from n-hexane and ethyl acetate fraction showed strong activity. Minimal inhibitory concentration, MIC of S. pubescens extract was measured and resulted showing 8 μg/mL with n-hexane fraction and 32 μg/mL with ethyl acetate fraction against S. iniae. The growth of S. iniae was fully inhibited by adding 50 μg/mL (final concentration) of n-hexane or ethyl acetate fraction in the liquid media. It is needed that, from these results, purification and isolation of responsible active compound(s) of these activities and further study on the synergy effect using combination with commercial antibiotics against fish pathogenic bacteria.

• 한국수산과학회지
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• 제36권2호
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• pp.129-135
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• 2003

2001년 9월부터 2002년 7월 사이 낙동강 하구역에서 otter trawl을 이용하여 계절별로 어류를 채집하여 종조성 및 양적변동을 파악하고, 하구둑 건설이전 어류 조사와 비교하였다. 본 조사에서는 총 21과 30종의 어류가 채집되었으며, 문절망둑과 주둥치가 최우점종이었는데, 이들 어종이 전체 채집 개체수와 성체량의 $71.2\%$와 $67.8\%$를 차지하였다. 그 외 양태, 꼼치 등이 우점하였다. 채집종수는 봄과 가을에, 개체수 및 생체량은 봄과 여름에 높았으나, 겨울에는 모두 낮았다. 하구둑이 완공되기 직전에 실시된 어류 조사와 비교한 결과 어류 종조성의 변화가 뚜렷하였다. 과거의 우점종인 흰베도라치, 실양태, 밴댕이 및 고등어 등은 채집량이 크게 감소한 반명, 문절망둑, 양태, 꼼치, 두줄망둑 및 농어 등은 채집량이 크게 증가하였다. 하구둑 건설 이후 강 상류로부터 내려오는 담수의 유입이 수시로 차단됨에 따라 하구역에서의 해수 유동 변동이 초래되었으며, 그 결과 하구역에 각종 부유물이 축척되는 등의 저질 환경이 변화가 일어나 어류상에 영향을 준 것으로 보인다.

• 한국수산과학회지
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• 제43권6호
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• pp.642-647
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• 2010

This study examined the antimicrobial activity of Myagropsis yendoi (MY). The antimicrobial activity of ethanol and aqueous MY extracts were measured using a paper disc assay. The MY ethanol extract had the best antimicrobial activity. It inhibited the growth of Candida tropicalis and Gram-positive bacteria such as Bacillus subtilis, Listeria innocua, L. monocytogenes, and Staphylococcus aureus at 4 mg/mL. The minimum inhibitory concentration (MIC) of the MY ethanol extract ranged from 0.1 to 0.5%. The MY ethanol extract inhibited the growth of B. subtilis and L. innocuaat concentrations of 0.15% and 0.1%, respectively. The antimicrobial activity of the MY ethanol extract was not affected by heating at $121^{\circ}C$ for 15 min or pH 2.10. Therefore, the main substances responsible for the antimicrobial activity of the MY ethanol extract are believed to be stable with changing heat and pH.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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• pp.505-505
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• 2000

Perkinsus sp. has been identified as responsible organism for the decrease in Manil clam production along the west and south coast of Korea. Monthly investigation on infection intensity and pathology of Perkinsus infected Manila clam population was carried out in Komsoe Bay located in the west coast during February and December 1999. About one hundred clams were collected each month for the analysis. Infected clams were incubated in fluid thioglycollate media over a week, stained with iodine solution, digested with 2M NaOH and the number of Perkinsus present in an individual recorded. Histological slides were also prepared from infected clams and their pathologic symptoms were examined using a microscope. Trophozoites of Perkinsus sp. were dominantly distributed on gills and epithelia of digestive glands however a few numbers could be detected at siphons and foot tissues. Heavily infected clams often exhibited white spots on mantle and foot tissues due to the inflammatory reaction of the hemocytes, forming nodules. Trophozoites were also found along the connective tissues of follicles during spawning season indicating that Perkinsus sp. may disturb reproduction of the clam. Total number of Perkinsus sp. in an individual clam varied from none to 9, 550, 000 with a monthly mean of 279, 663 to 2, 198, 558 during the course of study. The number of Perkinsus sp. in the clam was found to lowest durin July and August when unusually low salinity was recorded in this area due to the heavy rain. Highest monthly infection intensity in terms of total number of Perkinsus sp. i clam was observed in February, when water temperature recorded as lowest during the study. Small size of clams with shell length of ten mm or less were not infected with Perkinsus sp. It was concluded that Perkinsus infection in Manila clam is in pa controlled by changes in salinity and clam growth; low salinity environment minimize infection intensity while tile clams get more Perkinsus as they grow.

• 한국어병학회지
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• 제11권1호
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• pp.69-76
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• 1998

매년 폐사가 발생해 온 서해안 연안의 고창과 태안에서 채집한 양식 바지락에서 복합포자충류인 Perkinsus sp.가 관찰되었다. 기생충에 감염된 바지락은 육안적으로 아가미와 육질의 표면에서 유백색의 결절이 나타났다. 기생충의 영양체는 편재된 핵을 가지고 있으며, 아가미와 외투막, 간 췌장, 생식소 조직에서 이분열에 의해 증식하며, 육아종의 형성과 혈구의 침윤을 유발하였다. 감염된 바지락을 FTM에 배양한 결과 영양체의 크기가 커지면서 루골용액에 의해 검게 염색된 구형의 유주자낭들 형성하였다. Perkinsus sp.의 평균 감염율은 9개월의 조사 기간 동안 고창이 73.1%, 태안이 94.8%로 나타났으며, 감염율은 각장의 크기가 클수록 증가하는 경향을 나타내었다. Hemacolor kit는 바지락의 대량폐사와 밀접한 연관이 있는 Perkinsus sp.의 영양체의 신속진단에 유용한 것으로 나타났다.

• Fisheries and Aquatic Sciences
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• 제19권2호
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• pp.8.1-8.11
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• 2016

To quantitatively estimate the influence of cuttlebone on the target strength (TS) of golden cuttlefish, the cuttlebone was carefully extracted from 19 live cuttlefish caught using traps in the inshore waters around Geojedo, Korea, in early May 2010 and the TS was measured using split-beam echosounders (Simrad ES60 and EY500). The TS-length relationships for the cuttlefish (before the extraction of cuttlebone, Fish Aquat Sci. 17:361-7, 2014) and the corresponding cuttlebone were compared. The cuttlebone length ($L_b$) ranged from 151 to 195 mm (mean $L_b$ = 168.3 mm) and the mass ($W_b$) ranged from 29.3 to 53.2 g (mean $W_b$ = 38.8 g). The mean TS values at 70 and 120 kHz were -33.60 dB (std = 1.12 dB) and -32.24 dB (std = 1.87 dB), respectively. The mean TS values of cuttlebone were 0.19 dB and 0.04 dB lower than those of cuttlefish at 70 and 120 kHz, respectively. For 70 and 120 kHz combined, the mean TS value of cuttlebone was -32.87 dB, 0.11 dB lower than that of cuttlefish (-32.76 dB). On the other hand, the mean TS value of cuttlebone predicted by the regression ($TS_b$ = 24.86 $log_{10}$ $L_b$ - 4.86 $log_{10}$ ${\lambda}$ - 22.58, $r^2$ = 0.85, N = 38, P < 0.01) was -33.10 dB, 0.04 dB lower than that of cuttlefish predicted by the regression ($TS_c$ = 24.62 $log_{10}$ $L_c$ - 4.62 $log_{10}$ ${\lambda}$ - 22.64, $r^2$ = 0.85, N = 38, P < 0.01). That is, the contribution of cuttlebone to the cuttlefish TS determined by the measured results was slightly greater than that by the predicted results. These results suggest that cuttlebone is responsible for the TS of cuttlefish, and the contribution is estimated to be at least 99 % of the total echo strength.