Biochemical and molecular analysis of deltamethrin resistance in the common bed bug (Hemiptera: Cimicidae).

Yoon, Kyong Sup,Kwon, Deok Ho,Strycharz, Joseph P,Hollingsworth, Craig S,Lee, Si Hyeock,Clark, J Marshall Entomology Dept., B.P. Bishop Museum 2008 Journal of medical entomology Vol.45 No.6

<P>This study establishes deltamethrin resistance in a common bed bug, Cimex lectularius L., population collected from New York City (NY-BB). The NY-BB population was 264-fold more resistant to 1% deltamethrin in contact bioassay compared with an insecticide-susceptible population collected in Florida (FL-BB). General esterase, glutathione S-transferase, and 7-ethoxycoumarin O-deethylase activities of NY-BB were not statistically different from those of FL-BB. cDNA fragments that encoded the open reading frame of voltage-sensitive sodium channel alpha-subunit genes from the FL-BB and NY-BB populations, respectively, were obtained by homology probing polymerase chain reaction (PCR) and sequenced. Sequence alignment of the internal and 5' and 3' rapid amplification of cDNA ends (RACE) fragments generated a 6500-bp cDNA sequence contig, which was composed of a 6084-bp open reading frame (ORF) encoding 2027 amino acid residues and 186-bp 5' and 230-bp 3' untranslated regions (5' and 3' UTRs, respectively). Sequence comparisons of the open reading frames of the alpha-subunit genes identified two point mutations (V419L and L925I) that were presented only in the NY-BB population. L925I, located the intracellular loop between IIS4 and IIS5, has been previously found in a highly pyrethroid-resistant populations of whitefly (Bemisia tabaci). V419L, located in the IS6 transmembrane segment, is a novel mutation. A Val to Met mutation at the corresponding position of the bed bug V419, however, has been identified in the tobacco budworm as a kdr-type mutation. This evidence suggests that the two mutations are likely the major resistance-causing mutations in the deltamethrin-resistant NY-BB through a knockdown-type nerve insensitivity mechanism.</P>

Biochemical and Molecular Analysis of Deltamethrin Resistance in the Common Bed Bug, Cimex lectularius Linnaeus (Hemiptera: Cimicidae)

Kyong Sup Yoon,Deok Ho Kwon,Joseph P. Strycharz,Craig S. Hollingsworth,J. Marshall Clark,Si Hyeock Lee 한국응용곤충학회 2009 한국응용곤충학회 학술대회논문집 Vol.2009 No.05

The present investigation establishes deltamethrin resistance in the common bed bug, Cimex lectularius, populationcollected from New York City (NY-BB). The mortality resistance ratio indicated that NY-BB population was 264-fold more resistant to 1% deltamethrin in contact bioassay compared to one insecticide- susceptible population collected in Florida (FL-BB). Specific enzyme activities (general esterase, glutathione S-transferase, and 7-ethoxycoumarin O-deethylase) of NY-BB were not statistically different from those of FL-BB, indicating that the metabolic factors are not associated with the deltamethrin resistance in NY-BB. Complementary DNA fragments that encoded the open reading frame of voltage-sensitive sodium channel α-subunit genes from the FL-BB and NY-BB were obtained by homology probing PCR and sequenced. Sequence alignment of the internal and 5’ and 3’ RACE fragments generated a 6500 bp cDNA sequence contig, which was composed of a 6084 bp open reading frame (ORF) encoding 2027 amino acid residues and 186 bp 5’ and 230 bp 3’ untranslated regions (5’ and 3’UTRs, respectively). Sequence comparisons of the complete open reading frames of the sodium channel genes identified two point mutations (V419L and L925I) that were presented only in the NY-BB population. L925I, located the intracellular loop between IIS4 and IIS5, has been previously found in the pyrethroid-resistant populations of whitefly (Bemisia tabaci) that was more than 100-fold resistant to fenpropathrin. V419L, located in the IS6 transmembrane segment, is a novel mutation. This evidence suggests that the two mutations are likely the major resistance-causing mutations in the deltamethrin-resistant NY-BB via a knockdown-type nerve insensitivity mechanism.

매미 울음 시작 및 종료에 영향을 미치는 환경요인

기경석 ( Kyong-seok Ki ),이재윤 ( Jae-yoon Lee ),김윤재 ( Yoon-jae Kim ),김종섭 ( Jong-sup Kim ),성찬용 ( Chan-yong Sung ),윤기상 ( Ki-sang Yoon ) 한국환경생태학회 2016 한국환경생태학회 학술대회지 Vol.2016 No.2

본 연구는 여름철 도심지에 서식하는 매미류의 울음 시작및 종료에 영향을 미치는 환경요인을 밝히는데 그 목적이 있다. 연구대상지는 서울시 서초구 신반포한신7차아파트단지와 경기도 고양시 일산동구 호수마을2단지 현대아파트로 선정하였다. 연구기간은 2015년 7월 말부터 8월 말까지 2개월간 진행하였다. 연구대상종은 여름철 도시녹지에서 주로번식울음을 내는 참매미, 말매미, 유지매미를 선정하였다. 매미 울음 녹음은 Idam PRO U11 Digital Voice Recorder를 이용하여 매일, 24간 녹음하였다. 녹음장비는 아파트 단지내 녹지를 향하게 설치하였고 설치 높이는 약 2.5m이었다. 녹음 파일 유형은 MP3, 샘플 속도는 44100Hz로 세팅하였고, 마이크는 녹음기에 내장된 10㎜지향성 마이크 2대에 윈드스크린을 장착하였다. 환경요인은 기상청(http://www.kma.go.kr)의 기온, 강수량, 습도, 일조량 자료를 분석하였다. 매미 울음 분석방법은 참매미, 말매미는 5분단위로 울음유무를 점수화하여 1시간당 누적 울음점수를 산출하였고, 별도로 울음 횟수를 셀 수 있는 말매미, 유지매미는 1시간당울음 횟수를 분석하였다. 연구내용은 매미류 울음의 일주기패턴 분석, 매미 울음의 시작 및 종료 시간 차이, 매미 울음의 시작 및 종료에 영향을 미치는 환경요인의 3단계로 실시하였다. 연구결과는 다음과 같다. 매미 울음의 일주기 패턴 분석결과 참매미는 일출과 동시에 일제히 울음을 시작하였고 06시경 울음의 피크에 도달하였다가 서서히 울음 빈도가 낮아졌다. 말매미는 울음 시작 시간은 일정하지 않으나 약 10시경 울음의 피크에 도달하였고 일몰과 동시에 일제히울음을 종료하였다. 유지매미는 참매미나 말매미에 비해 울음 빈도가 낮았으며, 07시경부터 울음을 울기 시작하다가 18시경 울음이 피크에 도달하였고 일몰 이후 20시에서 22시 사이에 울음을 종료하였다. 매미 울음의 시작 및 종료시간 분석 결과 참매미는 평균5시 21분에, 말매미는 7시 40분에 울음을 시작하여 참매미가 말매미보다 평균 2시간 19분 먼저 울음을 시작하였다 (p<0.000). 울음 종료는 참매미는 평균 18시 31분, 말매미는 평균 19시 51분으로 말매미가 참매미보다 평균 1시간 20분 늦게 울음을 종료하였다(p<0.000). 매미 울음의 시작 및 종료에 영향을 미치는 환경요인 분석 결과 울음 시작의 경우 참매미는 일출과 양의 상관관계(p=0.029)를 나타내었고, 최저기온과 음의 상관관계(p<0.000)를 나타내었다. 울음 종료의 경우 말매미는 일출과 상관관계를 나타내지 않았고, 평균기온(p=0.029) 및 최저기온(p=0.026)과 음의 상관관계를 나타내었다.

Use of TachoSil<SUP>Ⓡ</SUP> to prevent pancreatic leak following distal pancreatectomy; A prospective multicenter, randomized, and controlled study

Joon Seong Park,Doo-ho Lee,Jin-Young Jang,Youngmin Han,Dong Sup Yoon,Jae Keun Kim,Ho-Seong Han,Yoo Seok Yoon,Dae Wook Hwang,Chang Moo Kang,Ho Kyong Hwang,Woo Jung Lee,Jin Seok Heo,Ye Rim Chang,Mee Joo 한국간담췌외과학회 2015 한국간담췌외과학회 학술대회지 Vol.2015 No.9

A point mutation in a glutamate-gated chloride channel confers abamectin resistance in the two-spotted spider mite, Tetranychus urticae Koch

Deok Ho Kwon,Kyong Sup Yoon,J. Marshall Clark,Si Hyeock Lee 한국응용곤충학회 2010 한국응용곤충학회 학술대회논문집 Vol.2010 No.05

The molecular mechanisms and genetics of abamectin resistance mediated by target site insensitivity in the two-spotted spider mite, Tetranychus urticae, were investigated by comparing two isogenic AbaS and AbaR strains. Cloning and sequencing of full-length cDNA fragments of GABA-gated chloride channel genes revealed no polymorphisms between the two strains. However, sequence comparison of the full-length cDNA fragment of a T. urticae glutamate-gated chloride channel gene (TuGluCl) identified a G323D point mutation as being tentatively related with abamectin resistance. In individual F2 progenies obtained by backcrossing, the G323D genotype was confirmed to correlate with abamectin resistance. Bioassays using progeny from reciprocal crossings revealed that the abamectin resistance trait due to TuGluCl insensitivity is incompletely recessive.

Molecular Mechanism and Detection of Pyrethroid Resistance in the Common Bed Bug, Cimex lectularius

Deok Ho Kwon,Keon Mook Seong,Kyong Sup Yoon,John Marshall Clark,Si Hyeock Lee 한국응용곤충학회 2014 한국응용곤충학회 학술대회논문집 Vol.2014 No.04

The common bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), is an ectoparasitic pest that feeds on humans as well as other mammals. We investigate that point mutations on the voltage-sensitive sodium channel are associated with the resistance to pyrethroids. Two point mutations (V419L and L925I) in the voltage-sensitive sodium channel (VSSC) α-subunit gene have been identified in deltamethrin-resistant bed bugs. L925I, located the intracellular loop between IIS4 and IIS5, has been previously found in a highly pyrethroid-resistant populations of whitefly. V419L, located in the IS6 transmembrane segment, is a novel mutation. To establish a population-based genotyping method as a molecular resistance monitoring tool, a quantitative sequencing (QS) protocol was developed. Frequency prediction equations were generated from the plots by linear regression, and the signal ratios were shown to highly correlate with resistance allele frequencies (r2 > 0.993). In addition to QS, the filter contact vial bioassay (FCVB) method was established and used to determine the baseline susceptibility and resistance of bed bugs to pyrethroids. A pyrethroid-resistant strain showed > 9375- and 6990-fold resistance to deltamethrin and λ-cyhalothrin, respectively. Resistance allele frequencies in different bed bug populations predicted by QS correlated well with the FCVB results, confirming the roles of the two mutations in pyrethroid resistance. Taken together, employment of QS in conjunction with FCVB method should greatly facilitate the detection and monitoring of pyrethroid resistant bed bugs in the field.

Determination of permethrin resistance allele frequency of human head louse, Pediculus humanus capitis, populations by quantitative sequencing

Deok Ho Kwon,Keon mook Seong,Kyong Sup Yoon,J. Marshall Clark,Won Ja Lee,Yong Joon Ahn,Si Hyeock Lee 한국응용곤충학회 2008 한국응용곤충학회 학술대회논문집 Vol.2008 No.05

A quantitative sequencing (QS) protocol that detects the frequencies of sodium channel mutations (M815I, T917I and L920F) responsible for knockdown resistance in permethrin-resistant head lice was tested as a population genotyping method. Genomic DNA fragments of the sodium channel α-subunit gene that encompass the three mutation sites were PCR-amplified from individual head lice with either resistant or susceptible genotypes, and combined together in various ratios to generate standard DNA template mixtures for QS. Following sequencing, the signal ratios between resistant and susceptible nucleotides were calculated and plotted against the corresponding resistance allele frequencies. Quadratic regression coefficients of the plots were close to 1, demonstrating that QS is highly reliable for the prediction of resistance allele frequencies. Prediction of resistance allele frequencies by QS in several globally collected lice samples including 12 Korean lice populations suggested that permethrin resistance varied substantially amongst different geographical regions. Three local populations of Korean lice were determined to have 9.8-36.7% resistance allele frequencies, indicating that an urgent resistance management is needed. QS should serve as a preliminary resistance monitoring tool for proper management strategies by allowing early resistance detection.

Pyrethroid resistance monitoring of the common bedbug, Cimex lectularius L. based on quantitative sequencing and residual contact vial bioassay

Keon-Mook Seong,Da-Young Lee,Kyong Sup Yoon,J. Marshall Clark,Si Hyeock Lee 한국응용곤충학회 2009 한국응용곤충학회 학술대회논문집 Vol.2009 No.10

Two point mutations (V419L and L925I) in the voltage-sensitive sodium channel (VSSC) α-subunit gene have been identified in deltamethrin-resistant bedbugs. To predict resistance allele frequencies of sodium channel mutations (V419L and L925I) in bedbugs at a population level, we developed quantitative sequencing (QS) protocol. The signal ratios between resistant and susceptible nucleotides were generated from sequencing chromatogram and plotted against the corresponding resistance allele frequencies. Linear regression coefficients of the plots were close to 1 (r2 = 0.9928 and 0.9998), suggesting that the signal ratios are reliable correlated with the resistance allele frequencies. To enable on-site monitoring of pyrethroid resistance in bed bugs, residual contact vial (RCV) bioassay method was established and used to determine median lethal concentration (LC50) values to deltamethrin for various bed bug strains. Resistance allele frequencies in these bedbug strains predicted by QS were correlated well with the RCV bioassay results, confirming the roles of two mutations in pyrethroid resistance. Taken together, employment of QS in conjunction with RCV bioassay should greatly facilitate resistance monitoring of bedbugs in the field.

Proliferation and Excretion of Bartonella quintana in Body and Head Lice Following Oral Challenge

Ju Hyeon Kim,Domenic J. Previte,Kyong Sup Yoon,John M. Clark,Si Hyeock Lee 한국응용곤충학회 2013 한국응용곤충학회 학술대회논문집 Vol.2013 No.04

The body and head lice (Pediculus humanus humanus and Pediculus humanus capitis, respectively) are hematophagous ectoparasites of humans and only the body louse between two is known to transmit three bacterial diseases through its feces. The proliferation profiles of Bartonella quintana, the causative agent of trench fever, inside the louse body and its excretion patterns were investigated in the two louse subspecies following oral challenge with B. quintana-infected blood meal. The initial density of B. quintana was sustained inside head lice without any noticeable proliferation for the entire period after infection. In contrast, B. quintana proliferated rapidly inside body lice and the maximum density reached at 10 days post-infection. The numbers of bacteria detected in feces from infected lice were almost the same and steadily decreased over time in both body and head lice. Nevertheless, the viability of the bacteria, as determined by fluorescence, was significantly higher in body louse feces, especially at 1 day post-infection and this tendency lasted for 11 days. These findings suggest that excretion of feces containing more viable B. quintana that is proliferated inside body lice following ingestion of infected blood meal is responsible for the higher vector competence of body lice.

Treatment Results of Small Intestinal Gastrointestinal Stromal Tumors Less than 10 cm in Diameter: A Comparison between Laparoscopy and Open Surgery

Ihn, Kyong,Hyung, Woo Jin,Kim, Hyoung-Il,An, Ji Yeong,Kim, Jong Won,Cheong, Jae-Ho,Yoon, Dong Sup,Choi, Seung Ho,Noh, Sung Hoon The Korean Gastric Cancer Association 2012 Journal of gastric cancer Vol.12 No.4

Purpose: To evaluate the technical feasibility and oncologic safety, we assessed the short-term and long-term outcomes of laparoscopic resection of the small bowel gastrointestinal stromal tumors smaller than 5 cm by comparing those of open surgery by subgroup analysis based on tumor size. Materials and Methods: From November 1993 to January 2011, 41 laparoscopic resections were performed among the 95 patients who underwent resection of small intestine ${\leq}10$ cm in diameter. The clinicopathologic features, perioperative outcomes, recurrences and survival of these patients were reviewed. Results: The postoperative morbidity rates were comparable between the 2 groups. Laparoscopic surgery group showed significantly shorter operative time (P=0.004) and duration of postoperative hospital stay (P<0.001) than open surgery group and it was more apparent in the smaller tumor size group. There were no difference in 5-year survival for the laparoscopic surgery versus open surgery groups (P=0.163), and in 5-year recurrence-free survival (P=0.262). The subgroup analysis by 5 cm in tumor size also shows no remarkable differences in 5-year survival and recurrence-free survival. Conclusions: Laparoscopic resection for small bowel gastrointestinal stromal tumors of size less than 10 cm has favorable short-term postoperative outcomes, while achieving comparable oncologic results compared with open surgery. Thus, laparoscopic approach can be recommended as a treatment modality for patients with small bowel gastrointestinal stromal tumors less than 10 cm in diameter.