• Parasites, Hosts and Diseases
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• 제53권4호
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• pp.439-445
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• 2015

A survey of intestinal helminths was undertaken in riparian people in Xieng Khouang Province, Lao PDR. Fecal specimens were collected from 643 people (289 males and 354 females) residing in 4 districts (Nonghet, Kham, Phoukout, and Pek) and were examined by the Kato-Katz technique. The overall helminth egg positive rate was 41.2%, and hookworms revealed the highest prevalence (32.7%) followed by Trichuris trichiura (7.3%) and Ascaris lumbricoides (5.6%). The positive rate for small trematode eggs (STE), which may include Opisthorchis viverrini, heterophyids, and lecithodendriids, was 4.4%. For recovery of adult helminths, 12 STE or nematode/cestode egg-positive people were treated with 40 mg/kg praziquantel and 15 mg/kg pyrantel pamoate, and then purged. Mixed infections with 2 Haplorchis species (H. pumilio and H. taichui), Centrocestus formosanus, Opisthorchis viverrini, a species of cestode (Taenia saginata), and several species of nematodes including hookworms and Enterobius vermicularis were detected. The worm load for trematodes was the highest for H. pumilio with an average of 283.5 specimens per infected person followed by C. formosanus, H. taichui, and O. viverrini. The worm load for nematodes was the highest for hookworms (21.5/infected case) followed by E. vermicularis (3.2/infected case). The results revealed that the surveyed areas of Xieng Khouang Province, Lao PDR are endemic areas of various species of intestinal helminths. The STE found in the surveyed population were verified to be those of heterophyids, particularly H. pumilio.

• Journal of Plant Biotechnology
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• 제37권2호
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• pp.125-132
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• 2010

Rice is the staple food of more than 50% of the worlds population. Cultivated rice has the AA genome (diploid, 2n=24) and small genome size of only 430 megabase (haploid genome). As the sequencing of rice genome was completed by the International Rice Genome Sequencing Project (IRGSP), many researchers in the world have been working to explore the gene function on rice genome. Insertional mutagenesis has been a powerful strategy for assessing gene function. In maize, well characterized transposable elements have traditionally been used to clone genes for which only phenotypic information is available. In rice endogenous mobile elements such as MITE and Tos (Hirochika. 1997) have been used to generate gene-tagged populations. To date T-DNA and maize transposable element systems has been utilized as main insertional mutagens in rice. A main drawback of a T-DNA scheme is that Agrobacteria-mediated transformation in rice requires extensive facilities, time, and labor. In contrast, the Ac/Ds system offers the advantage of generating new mutants by secondary transposition from a single tagged gene. Revertants can be utilized to correlate phenotype with genotype. To enhance the efficiency of gene detection, advanced gene-tagging systems (i.e. activation, gene or enhancer trap) have been employed for functional genomic studies in rice. Internationally, there have been many projects to develop large scales of insertionally mutagenized populations and databases of insertion sites has been established. Ultimate goals of these projects are to supply genetic materials and informations essential for functional analysis of rice genes and for breeding using agronomically important genes. In this report, we summarize the current status of Ac/Ds-mediated gene tagging systems that has been launched by collaborative works from 2001 in Korea.

• 식물병연구
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• 제17권1호
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• pp.32-37
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• 2011

유기물, 석회질소, 요소 병행처리가 딸기 시들음병의 친환경적 방제인 태양열소독의 효과 증진여부를 밝히고자 논산딸기시험장의 비닐하우스에서 2006년과 2008년에 분석하였다. 딸기에서 분리한 Fusarium oxysporum f. sp. fragariae 7개 균주의 100% 치사시간은 $45^{\circ}C$에서 6.6일, $50^{\circ}C$에서는 5.1일이 소요되었고 100% 치사온도는 $46.7{\pm}0.1^{\circ}C$로 나타났다. 태양열 소독에 의해 유기물 처리구는 처리전보다 토양내 유기물 함량이 증가하였고, 석회질소 처리구는 산도, 유기물, 칼슘 함량이 증가하였으나 요소처리구는 차이가 없었다. 태양열 소독시 지온은 처리간에 차이를 나타냈으며 7월 30일부터 8월 10일까지가 가장 높았고($48.4\sim54.8^{\circ}C$) 유기물+석회질소 처리구가 다른 처리구보다 $3\sim4^{\circ}C$ 높게 유지되었다. 또한 토양내 시들음병균은 각 처리구 모두에서 사멸되었다. 시들음병 이병주율은 무처리는 2006년 20%, 2008년 13.3%의 발병율을 나타낸 반면 태양열 소독 처리구 모두에서는 시들음병 발생이 없었으며 처리간 유의성이 있었다. 따라서 딸기 시들음병 방제를 위한 유기물+석회질소를 병행한 태양열 소독 방법은 기존의 태양열소독방법을 보완하여 처리기간을 줄이면서도 효과적인 방법이 될 것이다.

• Molecules and Cells
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• 제25권4호
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• pp.467-478
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• 2008

Simple sequence repeats (SSRs) and interSSR (ISSR) marker systems were used in this study to reveal genetic changes induced by artificial selection for short/long larval duration in the tropical strain Nistari of the silkworm Bombyx mori. Artificial selection separated longer larval duration (LLD) ($29.428{\pm}0.723days$) and shorter larval duration (SLD) ($22.573{\pm}0.839days$) lines from a base, inbred population of Nistari (larval span of $23.143{\pm}0.35days$). SSR polymorphism was observed between the LLD and SLD lines at one microsatellite locus, Bmsat106 ($CA_7$) and at two loci of 1074 bp and 823 bp generated with the ISSR primer UBC873. Each of these loci was present only in the LLD line. The loci segregated in the third generation of selection and were fixed in opposite directions. In the $F_2$ generation of the $LLD{\times}SLD$ lines, the alleles of Bmsat106 and $UBC873_{1074bp}$ segregated in a 1:1 ratio and the loci were present only in the LLD individuals. $UBC873_{823bp}$ was homozygous. Single factor ANOVA showed a significant association between the segregating loci and longer larval duration. Together, the two alleles contributed to an 18% increase in larval duration. The nucleotide sequences of the $UBC873_{1074bp}$ and $UBC873_{823bp}$ loci had 67% A/T content and consisted of direct, reverse, complementary and palindromic repeats. The repeats appeared to be "nested" (59%) in larger repeats or as clustered elements adjacent to other repeats. Of 203 microsatellites identified, dinucleotides (67.8%) predominated and were rich in A/T and T/A motifs. The sequences of the $UBC873_{1074bp}$ and $UBC873_{823bp}$ loci showed similarity (E = 0.0) to contigs located in Scaffold 010774 and Scaffold 000139, respectively, of the B. mori genome. BLASTN analysis of the $UBC873_{1074bp}$ sequence showed significant homology of (nt.) 45-122 with upstream region of three exons from Bombyx. The complete sequence of this locus showed ~49% nucleotide conservation with transposon 412 of Drosophila melanogaster and the Ikirara insertions of Anopheles gambiae. The A + T richness and lack of coding potential of these small loci, and their absence in the SLD line, reflect the active process of genetic change associated with the switch to short larval duration as an adaptation to the tropics.

• Molecules and Cells
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• 제39권2호
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• pp.103-110
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• 2016

As a degenerative joint disease, osteoarthritis (OA) constitutes a major cause of disability that seriously affects the quality of life of a large population of people worldwide. However, effective treatment that can successfully reverse OA progression is lacking until now. The present study aimed to determine whether two small non-coding RNAs miR-29a and miR-140, which are significantly down-regulated in OA, can be applied together as potential therapeutic targets for OA treatment. MiRNA synergy score was used to screen the miRNA pairs that potentially synergistically regulate OA. An in vitro model of OA was established by treating murine chondrocytes with IL-$1{\beta}$. Transfection of miR-29a and miR-140 via plasmids was investigated on chondrocyte proliferation and expression of nine genes such as ADAMTS4, ADAMTS5, ACAN, COL2A1, COL10A1, MMP1, MMP3, MMP13 and TIMP metallopeptidase inhibitor 1 (TIMP1). Western blotting was used to determine the protein expression level of MMP13 and TIMP1, and ELISA was used to detect the content of type II collagen. Combined use of miR-29a and miR-140 successfully reversed the destructive effect of IL-$1{\beta}$ on chondrocyte proliferation, and notably affected the MMP13 and TIMP1 gene expression that regulates extracellular matrix. Although co-transfection of miR-29a and miR-140 did not show a synergistic effect on MMP13 protein expression and type II collagen release, but both of them can significantly suppress the protein abundance of MMP13 and restore the type II collagen release in IL-$1{\beta}$ treated chondrocytes. Compared with single miRNA transfection, cotransfection of both miRNAs exceedingly abrogated the suppressed the protein production of TIMP1 caused by IL-$1{\beta}$, thereby suggesting potent synergistic action. These results provided1novel insights into the important function of miRNAs' collaboration in OA pathological development. The reduced MMP13, and enhanced TIMP1 protein production and type II collagen release also implies that miR-29a and miR-140 combination treatment may be a possible treatment for OA.

• 생태와환경
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• 제42권3호
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• pp.317-330
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• 2009

패류를 이용한 오염하천의 수질개선 가능성을 확인하고자 CROM기술을 응용한 S-CROM기법을 개발하고 현장에 직접 적용하였다. 실험은 하천에 형성된 소형 보에서 실시하고 자연유속을 그대로 이용하였으며, 패류의 섭식활동을 위해 현장의 퇴적물을 첨가하였다. 실험은 처리조를 현장수(대조군), 현장수+퇴적물(대조군), 현장수+퇴적물+패류 30개체 (D1), 현장수+퇴적물+패류 60개체 (D2) 등 4가지로 구성하고, 유속은 450mL $min^{-1}$, 시료채취는 12시간(주, 야)간격으로 실시하였다. 환경요인으로는 현장에서 직접 수온, pH, DO, 전기전도도, 탁도 등을 측정하였고 시료를 채취하여 Chl-$\alpha$, SS, TN, TP, $NO_2$-N, $NO_3$-N, $NO_4$-N, $PO_4$-P, BOD, 식물플랑크톤 등을 분석하였다. 실험결과 유기물 제어능은 패류밀도와 처리시간에 따라 차이를 보였는데, 최대효과는 운영 2일째, 낮 동안 그리고 고밀도 처리군에서 나타났으며, 부유물질 (57%)과 조류(72%)의 감소를 보였다. 고농도의 암모니아와 인산을 배출하였던 CROM(김 등, 2009)보다 뚜렷하게 낮은 수준을 보였으며, 패류의 밀도효과는 유의하지 않았다. 비록 S-CROM이 CROM에 비하여 낮은 제어율을 보였으나 이는 상대적으로 낮은 패류밀도 및 빠른 유속 등이 원인으로 판단되었다. 따라서 S-CROM를 이용한 하천의 유기물 제어는 하천환경과 패류밀도를 적절하게 조합한다면 높은 수질개선 효과를 기대할 수 있을 것으로 사료되었다.

• Biomolecules & Therapeutics
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• 제22권3호
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• pp.184-192
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• 2014

${\beta}$-lapachone is a naturally occurring quinone that selectively induces apoptotic cell death in a variety of human cancer cells in vitro and in vivo; however, its mechanism of action needs to be further elaborated. In this study, we investigated the effects of ${\beta}$-lapachone on the induction of apoptosis in human gastric carcinoma AGS cells. ${\beta}$-lapachone significantly inhibited cellular proliferation, and some typical apoptotic characteristics such as chromatin condensation and an increase in the population of sub-G1 hypodiploid cells were observed in ${\beta}$-lapachone-treated AGS cells. Treatment with ${\beta}$-lapachone caused mitochondrial transmembrane potential dissipation, stimulated the mitochondria-mediated intrinsic apoptotic pathway, as indicated by caspase-9 activation, cytochrome c release, Bcl-2 downregulation and Bax upregulation, as well as death receptor-mediated extrinsic apoptotic pathway, as indicated by activation of caspase-8 and truncation of Bid. This process was accompanied by activation of caspase-3 and concomitant with cleavage of poly(ADP-ribose) polymerase. The general caspase inhibitor, z-VAD-fmk, significantly abolished ${\beta}$-lapachone-induced cell death and inhibited growth. Further analysis demonstrated that the induction of apoptosis by ${\beta}$-lapachone was accompanied by inactivation of the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. The PI3K inhibitor LY29004 significantly increased ${\beta}$-lapachone-induced apoptosis and growth inhibition. Taken together, these findings indicate that the apoptotic activity of ${\beta}$-lapachone is probably regulated by a caspase-dependent cascade through activation of both intrinsic and extrinsic signaling pathways, and that inhibition of the PI3K/Akt signaling may contribute to ${\beta}$-lapachone-mediated AGS cell growth inhibition and apoptosis induction.

• Molecules and Cells
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• 제27권3호
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• pp.329-336
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• 2009

To evaluate the involvement of translation initiation factors eIF4E and eIFiso4E in Chilli veinal mottle virus (ChiVMV) infection in pepper, we conducted a genetic analysis using a segregating population derived from a cross between Capsicum annuum 'Dempsey' containing an elF4E mutation ($pvr1^2$) and C. annuum 'Perennial' containing an elFiso4E mutation (pvr6). C. annuum 'Dempsey' was susceptible and C. annuum 'Perennial' was resistant to ChiVMV. All $F_1$ plants showed resistance, and $F_2$ individuals segregated in a resistant-susceptible ratio of 166:21, indicating that many resistance loci were involved. Seventy-five $F_2$ and 329 $F_3$ plants of 17 families were genotyped with $pvr1^2$ and pvr6 allele-specific markers, and the genotype data were compared with observed resistance to viral infection. All plants containing homozygous genotypes of both $pvr1^2$ and pvr6 were resistant to ChiVMV, demonstrating that simultaneous mutations in elF4E and eIFiso4E confer resistance to ChiVMV in pepper. Genotype analysis of $F_2$ plants revealed that all plants containing homozygous genotypes of both $pvr1^2$ and pvr6 showed resistance to ChiVMV. In protein-protein interaction experiments, ChiVMV viral genome-linked protein (VPg) interacted with both eIF4E and eIFiso4E. Silencing of elF4E and eIFiso4E in the VIGS experiment showed reduction in ChiVMV accumulation. These results demonstrated that ChiVMV can use both eIF4E and eIFiso4E for replication, making simultaneous mutations in eIF4E and eIFiso4E necessary to prevent ChiVMV infection in pepper.

• 한국균학회지
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• 제15권3호
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• pp.187-195
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• 1987

두가지 열처리법에 의한 균 분리방법을 사용하여, 보통균을 제외한 토양균의 분리와 그의 논토양중의 수직 및 계절별 분포를 파악하기 위하여 역곡동과 신원동의 논토양을 시료로 사용하였다. $42^{\circ}C$에서 2일간 배양후 $37^{\circ}C$로 배양하는 방법과 $70^{\circ}C$에서 15분간 열처리하는 방법을 사용하였다. $42^{\circ}C$ 배양법에서는 두 장소에서 분리된 토양균은 거의가 mesophile이었으며 thermotolerant fungi는 Asergillus fumigatus, thermophile로는 Sporotrichum thermophile과 Malbranchea pulchella var. sulfrea이었고, 이들 중 우점종은 Asergillus fumigatus이었다. 두 장소에서 9속, 14종이 분리동정되었으며 Sporotrichum thermophile, Talaromyces ucrainicus, Malbranchea pulchella var. sulfrea는 한국 미기록 종이다. $72^{\circ}C$ 열처리방법으로 분리한 경우 두 장소에서 10속, 20종이 분리동정되었으며, 분리된 균은 거의가 mesophile이었으며 thermotolerant fungi는 Asergillus fumigatus이었고, 우점종은 Talaromyces stipitatus이었다. 또한 Talaromyces helicus var. major, Emericella nidulans var. nidulans, Chaetomium subspirale, Neosartorya fishiri var. fischeri는 한국 미기록 종이다. 두가지 분리방법으로 분리된 토양균의 계절적 분포는 여름과 봄이 가을과 겨울보다 높았으며, 전체 균의 수와 우점종 균수, 그리고 나타나는 종의 빈도는 그 수직분포에 있어서 상층에서 가장 높았으나 하층으로 내려갈수록 감소하였다.

• 보존과학회지
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• 제36권5호
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• pp.333-338
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• 2020

이 연구는 국외에서 지중흰개미의 생태와 방제 연구를 위해 사용하는 Nile Blue A 염색약이 국내 전역에 서식하는 R. s. kyushuensis에 대한 적용 여부 및 적정 조건을 평가하기 위해 수행되었다. 0.05%, 0.10%, 0.25%(w/w) 농도로 여과지를 염색한 뒤 1, 3, 7일간 no-choice feeding test로 염색 여과지를 강제 섭식시켜 공시충을 염색시킨 뒤 4주 동안 생존률, 염색률, 염색의 유지 여부 등을 관찰하였다. 그 결과 공시충의 생존률은 약제의 농도가 낮을수록, 약제의 섭식기간이 짧을수록 높은 경향을 보였으며 반대로 염색률 및 선명도는 약제의 농도가 높고 약제의 섭식기간이 길수록 높게 나타나 반비례하는 양상을 보였다. 다양한 농도와 섭식기간 조건 중 0.05%에서 3일, 0.10% 농도에서 3일간 염색하였을 때 높은 생존률과 염색률, 염색의 유지기간을 동시에 만족시켜 적합한 조건으로 확인되었다. 본 실험 결과는 향후 실내 실험 단계의 흰개미 관련 연구에서 약제의 섭식 여부 확인 등에 활용할 수 있을 것으로 기대된다.