• Journal of Microbiology and Biotechnology
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• 제18권9호
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• pp.1584-1589
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• 2008

Although resistance of Helicobacter pylori to clarithromycin is a major cause of failure of eradication therapies, little information is available regarding gene mutations of clarithromycin-resistant primary and secondary H. pylori isolates in Korea. In the present study, we examined gene mutations of H. pylori 238 rRNA responsible for resistance to clarithromycin. DNA sequences of the 238 rRNA gene in 21 primary clarithromycin-resistant and 64 secondary clarithromycin-resistant strains were determined by PCR amplification and nucleotide sequence analyses. Two mutations of the 238 rRNA gene, A2143G and T2182C, were observed in primary clarithromycin-resistant isolates. In secondary isolates, dual mutation of A2143G+T2182C was frequently observed. In addition, A2143G+T2182C+ T2190C, A2143G+T2182C+C2195T, and A2143G+T2182C+A2223G were observed in secondary isolates. Furthermore, macrolide binding was tested on purified ribosomes isolated from T2182C or A2143C mutant strains with $[^{14}C]$erythromycin. Erythromycin binding increased in a dose-dependent manner for the susceptible strain but not for the mutant strains. These results indicate that secondary isolates show a greater variety of 238 rRNA gene mutation types than primary isolates, and triple mutations of secondary isolates are associated with A2143G+T2182C in H. pylori isolated from Korean patients.

• 한국동물위생학회지
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• 제29권3호
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• pp.277-285
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• 2006

Plasmids are covalently closed circular molecules of DNA that are stably inherited and replicate somewhat independently of the bacterial chromosome. Genes carried on plasmids can mediate a wide variety of important functions, including antibiotics (R plasmids) and heavy metals resistance, toxins production, cell penetration, iron chelation, complement resistance, and metabolic characteristics such as sucrose and lactose fermentation. Fifty strains of lactobacilli were isolated from 26 staters and 29 fermented milk products. They were classified 27 strains as Lactobacillus paracasei subsp paracasei, 11 stains as Lactococcus lactis subsp cremoris, 6 strains as L delbrueckii subsp lactis, 4 strains as L acidophius, and 2 strains as L delbrueckii subsp bulgaricus. All of these strains were examined for drug resistance and transferability of R plasmids. All of the isolates were sensitive to Am, C, CF, E, NB, P, T, and Te. But resistant to SXT 94% (47 strains), K 66% (33 strains), S 56% (28 strains), ENR 50% (25 strains), NOR 38% (19 strains) CIP 38% (19 strains), GM 16% (8 strains), and N 14% (7 strains), in order. And 32 different resistant patterns were found. The most frequently encountered patterns were CIP-ENR-K-NOR-S-SXT (5 strains). In vitro R plasmids transfer experiment, 57 antibiotic resistant strains which were not transfer to the recipient 2 Escherichia coli strains by conjugation, These results indicate that Lactobacillus in internal trade market' stater recognize R factor but transmissible R plasmid is not existed.

• Asian-Australasian Journal of Animal Sciences
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• 제19권7호
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• pp.970-977
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• 2006

Forage oat (Avena sativa L.) is grown extensively in a double-cropping system on dairy farms. Four oat varieties ('Swan', 'Targa', 'Foothill', and 'Nugene') were evaluated for forage production and forage quality during two growing seasons (spring and autumn) at two locations (central and southern region) in South Korea. The heading stage of four oat varieties was observed during spring, but the autumn season did not produce heading until harvest time except for the 'Swan' variety (early-maturing variety). The heading stage of 'Swan' in both locations was earlier compared to other varieties. The four varieties were resistant to both foliar disease and insects. Lodging resistance was higher during autumn except in 2002 at the central region, and late-maturing varieties ('Foothill' and 'Nugene') have lower lodging resistance. Dry matter (DM) content was significantly different between varieties (p<0.001). Comparing different varieties, 'Swan', an early-maturing variety, was highest in DM content. In DM, total digestible nutrients (TDN) and crude protein (CP) yield, the yield of oat varieties in the southern region was higher than in the central region, and forage yield of the oat varieties in the spring season was higher than during the autumn season. The DM and TDN yield showed significant differences between oat varieties. The CP content of oats grown in the central region (Cheonan) was lower than oats grown in the southern region (Daegu), and the spring season produced oats with lower CP compared to the autumn season. Among the four oat varieties, the CP content of late-maturing varieties was higher than the Swan variety (early-maturing variety). The acid detergent fiber (ADF) and neutral detergent fiber (NDF) contents were higher for the varieties grown in Cheonan and during the spring season. The ADF and NDF contents of late-maturing varieties were lower than the early-maturing variety. TDN and relative feed value (RFV) were higher for the varieties grown in Daegu and during the autumn season. Late-maturing variety had higher TDN and RFV than early-maturing variety. Our study showed differences in forage production and forage quality of oats grown in different locations, seasons and varieties. Forage quality as well as forage production was better in the southern region than in the central region. Forage quality was better during autumn, but forage production was better during spring. Late-maturing variety had better forage quality than the early-maturing variety. Therefore, late-maturing varieties are more suitable for use in the southern region.

• 환경위생공학
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• 제23권2호
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• pp.71-79
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• 2008

We examined 165 unchlorinated natural drinking water samples for the presence of E. coli group resistant to antimicrobial agent and chlorine in nothern Gyeongbuk area in 2007. Among 165 water samples, 21 samples(12.7%) were positive to total coliforms and Six genus, 16 strains of E. coli groups isolated from 16 samples showed resistance against more than one antimicrobial agent such as Ampicillin, Tetracycline and Chloroamphenicol. Among 16 strains, 14 strains resistant to Ampicillin, 9 strains resistant to Tetracycline and one strain resistant to Chloroampenicol. but all 16 strains did not contain any integron gene cassettes, which contribute to the spread of antimicrobial resistance alleles by lateral gene transfer of gene cassettes in a variety of enteric bacteria. The minimal inhibitory concentration(MIC) of 14 strains which showed resistant to Ampicillin was between $12{\mu}g/m{\ell}$ and $32{\mu}g/m{\ell}$, Nine strains resistant to Tetracycline showed between $32{\mu}g/m{\ell}$ and $128{\mu}g/m{\ell}$ and one strain resistant to Chloroampenicol showed $128{\mu}g/m{\ell}$. The chlorine sensitivity of 16 strains isolated from unchlorinated natural water sample did not show any difference among strains by the concentration of initial free chlorine and elapsed time after chlorine treatment. All 16 strains were killed after 1hr. exposure at $0.2mg/m{\ell}$ of free chlorine per liter or 30minutes exposure at $0.4mg/m{\ell}$ of free chlorine per liter.

• Journal of Plant Biotechnology
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• 제5권3호
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• pp.173-179
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• 2003

The combination of a radiation technique with an in vitro culture system was appiled to develop submergence tolerant rice. The 3,000 $M_3$ lines with an average 80 percent of fertile grain were utilized for the selection of submergence tolerance. Salt tolerant lines were selected based on high plant height, root length and root number after submergence in plastic pots. Of the lines tested, the tolerant line (403-6) showed a dramatic difference in morphological traits under submergence compared to its original variety (Dongjinbyeo). It was suggested that genetic variations between the original variety and $M_3$-403-6 did exist. The levels of $\alpha$-amylase and alcohol dehydrogenase activities were significantly increased in the mutant line compared to its original variety. The mutant with greater tolerance showed less electrolyte leakage indicating a greater membrane integrity and better survival. Also, this line was much more resistant to a salt stress of $1.25\%$ than the original variety. The proline level of the line was significantly (p<0.01> higher than that of the original variety. The relationships between the inhibition of growth caused by stress and the physiological changes in the plant cell were discussed.

• 한국약용작물학회지
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• 제11권5호
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• pp.392-396
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• 2003

참당귀 품종별 정식시기에 따른 생육 및 추대반응을 구명하고자 수행한 시험결과를 요약하면 다음과 같다. 1. 생존율은 만추당귀, AGJ90-1, 진부재래 공히 정식시기가 늦어짐에 따라 생존율이 낮아지는 경향이었으며 4월 25일 이후 정식에서는 현저히 낮았다. 2. 초기생육은 품종별 모두 조기 정식에서 생육량이 많고 만기 정식에서 생육량이 적어지는 경향으로 정식시기별 유의차가 인정되었으나 생육후기에는 유의차가 인정되지 않았다. 3. 품종별 추대율은 내추대성인 만추당귀는 $1.0{\sim}8.1%$, 중간형인 AGJ90-1은 $5.9{\sim}20.3%$, 추대성인 진부채래 $58.5{\sim}74.6%$ 범위로 품종의 추대성 정도에 따라 추대율의 차이가 크게 나타났다. 4. 정식시기별 추대율은 만추당귀, AGJ90-1, 진부재래공히 조기정식에서 추대율이 높고 만기정식에서 낮아지는 경향이었다. 5. 품종의 정식시기별 추대반응은 내추대성 품종은 둔감하게 반응하고 추대성에서는 민감하게 반응하였다. 6. 10a당 수량은 만추당귀는 4월 5일 정식에서 389 kg으로 가장 높고, AGJ90-1은 4월 15일에 377 kg, 진부재래는 4월 25일에 133 kg으로 가장 높았다.

• 한국육종학회지
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• 제40권1호
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• pp.58-62
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• 2008

간식용 풋땅콩의 선호도가 높음에 따라 대립 양질 다수성 신품종 육성을 위하여 자색종피인 'HYQ(CG)S-10'와 다수성인 '신광땅콩'을 인공교배하여 육성한 참원의 주요 특성을 요약하면 다음과 같다. 참원은 신풍초형으로 주경과 분지에서 개화 및 착협하고, 지상부 생장습성은 직립 소분지성이다. 참원은 팔광땅콩에 비해 성숙협수는 같으나 100립중이 90g으로 5g 더 높은 대립품종이다. 갈반병, 그물무늬병은 팔광땅콩 보다 강하고 낙엽율도 낮아 생육후기까지 녹엽 유지에 유리하였다. 참원의 기름함량은 25.8%, 단백질이 31.3%로서 팔광땅콩에 비해 높고, 탄닌함량이 낮고 유리당 함량이 높아 풋땅콩의 품질이 양호하다. 참원은 3년간 지역적응시험 결과 대광땅콩에 비하여 풋땅콩이 전국평균 8.93MT/ha로서 18%, 종실이 3.95ton/ha로서 4% 증수하였다. 참원은 개화가 빠르고 병해에도 강한 편이나 충분한 성숙을 위하여 강원도와 산간 고냉지를 제외한 지역에서 적응성이 높은 품종이다.

• 한국육종학회지
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• 제50권4호
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• pp.529-533
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• 2018

'효원6호'는 밥맛이 우수하고 복합저항성을 보이는 품종을 육성하고자 식감이 우수하고 밥을 지었을 때 윤기가 도는 양식미인 'Koshihikari'와 복합저항성을 보이는 '화영벼'를 인공교배하고, 2006년부터 2011년까지 계통육성을 하면서, 종자 및 쌀의 외관 특성이 우수하고, 임성, 초형이 양호하며, 포장 병 저항성이 우수한 계통을 선발하여 생산력 검정을 수행한 결과 우수성이 인정되어 품종으로 출원 및 등록되었다. '효원6호'는 중부평야지에서 8월 22일경에 출수하는 중만생종으로 화영벼에 비해 11일 정도 늦다. 간장과 이삭길이는 각각 85.7 cm, 21.1 cm로 화영벼보다 길었으며, 포기당 이삭수도 14.5개로 화영벼보다 많았다. '효원6호'는 성숙기 엽노화가 보통수준이며 중 정도의 내도복성을 보였으며, 강 수준의 내냉성을 보였다. 목도열병과 흰잎마름병 및 줄무늬 잎마름병에 대해 중 정도의 저항성을 나타내었으나 멸구에 대한 저항성은 없었다. '효원6호'의 현미 천립중은 21.36 g이며, 장폭비가 1.69인 단원형이다. 현미 아밀로스 함량과 단백질 함량은 17.7%와 6.7%로 화영벼보다 낮고, 밥의 윤기치는 83으로 화영벼에 비해 월등히 높은 것으로 나타났다.

• 한국균학회지
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• 제47권4호
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• pp.407-416
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• 2019

A common post-harvest disease of sweetpotato tuber is root rot caused by Fusarium solani in Korea as well as the other countries. Storage root rot disease was monitored earlier on sweetpotato (Ipomoea batatas) in storehouses of different locations in Korea. In the present study, an isolate SPL16124 was choosen and collected from Sweetpotato Research Lab., Bioenergy Crop Research Institute, NICS, Muan, Korea, and confirmed the identification as Fusarium solani by conidial and molecular phylogenetic analysis (internal transcribed spacer ITS and translation elongation factor EF 1-α gene sequences). The isolate was cultured on potato dextrose agar, and conidiation was induced. The fungus was screened for Fusarium root rot on tuber of 14 different varieties. Among the tested variety, Yenjami, Singeonmi, Daeyumi, and Sinjami showed resistant to root rot disease. Additionally, the pathogen was tested for pathogenicity on stalks of these varieties. No symptom was observed on the stalk, and it was confirmed that the disease is tissue specific.

• Asian Pacific Journal of Cancer Prevention
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• 제15권22호
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• pp.9939-9943
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• 2014

Lobaplatin, one of the third - generation platinum compounds, has shown encouraging anticancer activity in a variety of tumor types. However, the efficacy of lobaplatin in ovarian cancer has not been systemically evaluated. In this study, lobaplatin as a single agent and in combination with taxanes was investigated in - vitro and in an in vitro model of ovarian carcinoma. Using the sulforhodamine B (SRB) assay, the cytotoxic effects of lobaplatin alone and in combination with taxanes were compared with cisplatin and carboplatin in seven ovarian cancer cell lines. In addition, in - vitro antitumor activities were evaluated with cisplatin - sensitive and cisplatin - resistant human ovarian cancer xenografts in nude mice. The cytotoxicity of lobaplatin was similar to or higher than that of cisplatin and carboplatin, with $IC_{50}$ values from 0.9 to $13.8{\mu}mol/L$ in a variety of ovarian cancer cells. The combination of lobaplatin with docetaxel yielded enhanced cytotoxic activity in vitro. In addition, in platinum - sensitive ovarian cancer xenografts, lobaplatin alone showed similar antitumor activity to cisplatin and carboplatin. Furthermore, lobaplatin alone or in combination with docetaxel exhibited significant activity in platinum - resistant ovarian cancer xenografts. These results indicate that the use of lobaplatin alone or in combination with docetaxel might be a rational and novel therapeutic strategy for ovarian cancer. Further clinical development of lobaplatin is clearly warranted.