• Weed & Turfgrass Science
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• 제6권1호
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• pp.28-31
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• 2017

The mutation rate of proline in the position 197 (Pro197) in acetohydroxy acid synthase (AHAS) is highest among sulfonylurea (SU) herbicide-resistance mutants. Therefore, it is significant to investigate the resistance mechanism for the mutation and to develop the herbicides specific to the mutants. SU herbicide resistance mechanism of the mutants, 197Ser, 197Thr and 197Ala, in AHAS were targeted for designing new SU-herbicide. We did molecular dynamics (MD) simulation for understanding SU herbicide-resistance mechanisms of AHAS mutants and designed new herbicides with docking and MD evaluations. We have found that mutation to 197Ala and 197Ser enlarged the entrance of the active site, while 197Thr contracted. Map of the root mean square derivation (RMSD) and radius gyrations (Rg) revealed the domain indicating the conformations for herbicide resistant. Based on the enlarging-contracting mechanism of active site entrance, we designed new herbicides with substitution at the heterocyclic moiety of a SU herbicide for the complementary binding to the changed active site entrances of mutants, and designed new herbicides. We confirmed that our screened new herbicides bonded to both AHAS wild type and mutants with higher affinity, showing more stable binding conformation than the existing herbicides.

• 농업과학연구
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• 제41권1호
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• pp.17-22
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• 2014

This study was conducted to evaluate the efficacy of formulations and application timings of imazosulfuron+fentrazamide in rice field. Weeding efficacy of imazosulfuron+fentrazamide SC (75+300 g a.i./ha) was more than 95% except Bidens tripartita. The efficacy of this formulation was not related to its formulations but was highly related to application timing. Herbicide application before 5 days after transplanting was best timing to get a maximum weed control. Systemic application before and after transplanting was much higher than single application for weed control. Second leaf stage of Echinochloa spp. and sulfonylurea resistant Monochoria vaginalis was controled over 90% in the imazosulfuron+fentrazamide SC (75+300 g a.i./ha). Based on these data, imazosulfuron+fentrazamide can be applied to provide effective weed control especially in the field infested with herbicide resistant M. vaginalis.

• 한국잡초학회지
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• 제32권2호
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• pp.133-138
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• 2012

본 시험은 SU계 제초제 저항성 잡초의 발생이 전국적으로 문제가 되면서 새로운 작용기작을 가지는 4-HPPD 저해제인 tefuryltrione의 SU계 제초제 저항성 논잡초에 대한 야외 포장에서의 약효와 벼에 대한 선택성을 확인하고자 수행되었다. Tefuryltrione 단제로 이앙 10~15일 후에 처리하였을 때 피에 대해서는 약효가 미흡하였으나, mefenacet과의 합제에서는 피뿐만 아니라 올챙이고랭이와 물달개비에 대해서 매우 우수한 약효를 보였다. 특히, 일년생 뿐 아니라 지하부로도 월동을 하는 다년생 올챙이고랭이에 대해서도 우수한 약효가 있는 것을 확인할 수 있었다. 경기도 평택의 바이엘크롭사이언스(주) 기술연구소 시험 포장 등 3개시험 포장에서 제초제 저항성 초종인 미국외풀, 알방동사니, 마디꽃 등과 가막사리, 사마귀풀, 여뀌바늘 등에 대해서도 mefenacet+tefuryltrione 합제는 매우 우수한 약효를 보였다. 일반 벼 품종인 추청벼와 동진벼를 대상으로 시험한 결과 초기에 약간의 생육억제를 보이지만 회복되어 처리 후 20일 이후에는 별다른 문제가 없었다.

• 대한유전성대사질환학회지
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• 제6권1호
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• pp.52-57
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• 2006

Permanent neonatal diabetes(PND) is a rare form of diabetes characterized by insulin-requiring hyperglycemia that is diagnosed within the first 3 months of life. In most cases, the causes are not known. Recently, mutations in the gene KCNJ11 encoding the Kir6.2 subunit of the ATP-sensitive K+ charmel have been described in patients with PND. We report a child with PND due to a lysine-to-arginine substitution at position 170(K170R) of gene encoding Kir6.2 Our patient was diagnosed at 7 weeks of age and had been treated with subcutaneous insulin for 6.5 years. Recently, our patient has been changed from subcutaneous insulin to oral glibenclamide therapy at a daily dose of 7.5 mg 3 times a day(0.9 mg/kg/day) at the age of 6.5 years. Before glibenclamide therapy, c-peptide level was 0.1 ng/ml(normal 1.0-3.5 ng/ml) and hemoglobin HbA1c level was 7.8%(normal <6%). After 6 days of treatment, her c-peptide and insulin levels were 2.3 ng/ml and $9.6{\mu}U/ml$(normal $5-25{\mu}U/ml$), respectively. After 1 month later, the insulin and c-peptide levels were in the nonnal range without any episodes of hyper- or hypoglycemia. This case demonstrated that oral sulfonylurea may be the treatment of choice in PND patients with KCNJ11 mutation even at a young age.

• The Korean Journal of Physiology and Pharmacology
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• 제19권3호
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• pp.197-202
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• 2015

Sulfonylureas are widely used as an antidiabetic drug. In the present study, the effects of sulfonylurea administered supraspinally on immobilization stress-induced blood glucose level were studied in ICR mice. Mice were once enforced into immobilization stress for 30 min and returned to the cage. The blood glucose level was measured 30, 60, and 120 min after immobilization stress initiation. We found that intracerebroventricular (i.c.v.) injection with $30{\mu}g$ of glyburide, glipizide, glimepiride or tolazamide attenuated the increased blood glucose level induced by immobilization stress. Immobilization stress causes an elevation of the blood corticosterone and insulin levels. Sulfonylureas pretreated i.c.v. caused a further elevation of the blood corticosterone level when mice were forced into the stress. In addition, sulfonylureas pretreated i.c.v. alone caused an elevation of the plasma insulin level. Furthermore, immobilization stress-induced insulin level was reduced by i.c.v. pretreated sulfonylureas. Our results suggest that lowering effect of sulfonylureas administered supraspinally against immobilization stress-induced increase of the blood glucose level appears to be primarily mediated via elevation of the plasma insulin level.

• 농약과학회지
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• 제17권4호
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• pp.314-334
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• 2013

곡물류 모니터링 시료인 현미, 보리, 옥수수 3가지 작물을 대상으로 보편적으로 많이 사용되고 등록된 농약을 조사, 76종을 선정하여 QuEChERS AOAC Official 2007. 01. 법과 변형된 QuEChERS 법으로 LC-MS/MS를 이용하여 회수율 시험을 비교하였다. 1% acetic acid를 사용하여 추출하는 QuEChERS AOAC Official 2007. 01. 법의 0.05, 0.2 mg/kg 회수율 결과는 현미 32.4~139.0%, 보리 24.2~123.7%, 옥수수 29.0~117.2%였고, 그 중 sulfonylurea 계통인 azimsulfuron, ethoxysulfuron, flucetosulfuron, imazosulfuron에 대해 회수율이 낮게 나오는 문제가 있었으며, 이들 농약의 평균 회수율은 53.3%였다. 이런 문제를 해결하기 위해 QuEChERS 법의 추출용매를 1% formic acid가 함유된 acetonitrile 용매로 바꾼 결과, 0.05, 0.2 mg/kg 수준의 회수율은 현미 73.2~132.2%, 보리 80.9~136.8%, 옥수수 66.6~143.5%였으며 변이계수는 모두 10% 미만이었다. 문제시 되었던 sulfonylurea 계통의 농약의 회수율도 53.3%에서 90.5%로 증가하였다. 검출한계(limits of detection, LOD)와 정량한계(limits of quantification, LOQ)는 현미 0.24~1.92, 0.79~65.74 ng/g, 보리 0.12~21.12, 0.36~63.36 ng/g, 옥수수 0.28~100.8, 0.86~302.4 ng/g이었다. 변형한 QuEChERS 법을 모니터링 시료 현미, 보리, 옥수수에 적용하여 98개 시료를 분석한 결과 36개의 시료에서 26종의 농약이 검출되었다. 검출 농도가 가장 높은 농약은 tricyclazole로 1.17 mg/kg로 조사되었다. 변형한 QuEChERS법으로 전처리를 하여 질량분석기 뿐만 아니라 현재 많이 보급된 검출기인 ECD, NPD 및 UPLC에서도 분석이 가능한지 실험하였고, 현미, 보리, 옥수수의 평균 회수율은 ECD는 65.3~130.3%, NPD는 61.6~133.0%로 대부분의 농약들이 잔류농약 검색용을 목적으로 하는 다성분 분석의 기준인 70~130% 이내의 회수율과 30%의 미만의 변이계수 조건을 만족하였다.

• 농약과학회지
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• 제9권3호
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• pp.250-261
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• 2005

본 연구는 7년 동안 연속적으로 sulfonylurea(SU)계 제초제를 사용한 남부지역의 논에서 발생한 들에 대한 저항성 잡초 올챙이고랭이의 제초제 반응과 방제법을 구명하기 위하여 실시하였다. 온실 조건에서 SU계 제초제에 대한 저항성 및 감수성 생태형을 파종 후 10일에 azimsulfuron, bensulfuron, imazosulfuron 그리고 pyrazosulfuron을 처리하였을 때 감수성 생태형은 각 제초제의 추천량에서 완전히 방제되었으나 저항성생태형은 추천량의 10배량에서도 $20{\sim}30%$ 생존되었다. 생체중 50%를 억제하는 각 제초제의 농도($GR_{50}$)는 두 생태형 간에 현저한 차이가 있었으며, 조사된 4종류의 각 SU계 제초제들에 대한 $GR_{50}$는 감수성 생태형에 비해 $53{\sim}88$배 높게 나타났다. 또한 SU계 제초제 저항성 및 감수성 생태형의 올챙이고랭이로 부터 추출한 acetolactate synthase(ALS)에 대한 bensulfuron-methyl과 pyrazosulfuron-ethyl의 50%억제 저항성 생태형이 감수성 생태형보다 각각 498 및 126배 높게 나타났다. SU계 제초제 저항성 올챙이고랭이는 조기진단법에 의하여 적어도 3일 이내에 저항성 진단이 가능하였다. 올챙이고랭이 $1.5{\sim}2.5$엽기에서는 조사된 대부분의 비SU계 제초제들이 효과적이었으나 3.5엽기에서는 carfentrazone-ethyl, pyrazolate, simetryne가 매우 효과적이었다. 그리고 azimsulfuron+carfentrazone-ethyl+pyraminobac 입제와 pyraminobac+pyrazosulfuron+carfentrazone 입제는 벼에 약해 없이 SU계 저항성 올챙이고랭이에 매우 효과적이었다. SU계 혼합 제초제를 처리 후 생존한 저항성 올행이고랭이는 경엽처리제인 bentazone에 의해서 효과적으로 방제되었다.

• BMB Reports
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• 제30권1호
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• pp.13-17
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• 1997

The inhibitory effect of herbicides such as sulfonylurea derivatives, imidazolinones and pyrimidylsalicylate has been examined on the purified valine sensitive acetolactate synthase (ALS) from Serratia marcescens. The concentration of sulfometuron methyl which inhibits 50% of the ALS activity was 2.5 mM. The required concentrations of triasulfuron, primisulfuron methyl and imazaquin for the 50% inhibition of the ALS activity were 1 mM. The resistance of Serratia ALS to sulfometuron methyl, imazapyr and imazaquin is similar to that of E. coli ALS 1. However, pyrimidylsalicylate showed a potent inhibitory effect on the Serratia ALS almost 13 times more potent than on E. coli ALS II, which is known as herbicide-sensitive isozyme. The inhibitory mode was competitive against pyruvate. 150 value was determined to be $17{\mu}M$ in an assay mixture containing 20 mM pyruvate, and the $K_1$, value was calculated to be $0.4{\mu}m$ from the modified double reciprocal plot of 1/V versus $1/S^2$.

• The Korean Journal of Physiology and Pharmacology
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• 제5권2호
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• pp.157-163
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• 2001

The effects of dimethyl sulfoxide (DMSO) were studied in two groups of Xenopus oocytes, one expressing ATP sensitive $K^+\;(K_{ATP})$ channel comprised of sulfonylurea receptor SUR1 and inwardly rectifying $K^+$ channel subunit Kir6.2, and the other expressing renal $K_{ATP}$ channel ROMK2. At concentrations of $0.3{\sim}10%$ (vol/vol) DMSO inhibited whole cell Kir6.2/SUR1 currents elicited by bath application of sodium azide (3 mM) in a concentration-dependent manner. The inhibition constant and Hill coefficient were 2.93% and 1.62, respectively. ROMK2 currents, however, was not affected significantly by DMSO. The results support the idea that DMSO inhibits $K_{ATP}$ channel expressed in Xenopus oocyte through a protein-specific mechanism(s) that remains to be further elucidated.

• 한국광과학회:학술대회논문집
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• 한국광과학회 2002년도 정기총회 및 제9회 광과학 학술심포지움 논문초록
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• pp.69-69
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• 2002