• Title/Summary/Keyword: defective effects

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Brassinosteroid의 대사공학 (Metabolic Engineering of the Brassinosteroid Biosynthetic Pathways)

  • 이미옥;송기홍;이현경;정지윤;최빛나리;최성화
    • 한국식물생명공학회:학술대회논문집
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    • 한국식물생명공학회 2002년도 춘계학술대회
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    • pp.69-75
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    • 2002
  • Sterols play two major roles in plants: a bulk component in biological membranes and precursors of plant steroid hormones. Physiological effects of plant steroids, brassinosteroids (BRs), include cell elongation, cell division, stress tolerance, and senescence acceleration. Arabidopsis mutants that carry genetic defects in BR biosynthesis or its signaling display characteristic phenotypes, such as short robust inflorescences, dark-green round leaves, and sterility. Currently there are more than 100 dwarf mutants representing 7 genetic loci in Arabidopsis. Mutants of 6 loci, dwf1/dim1/cbb1, cpd/dwf3, dwf4, dwf5, det2/dwf6, dwf7 are rescued by exogenous application of BRs, whereas bri1/dwf2 shares phenotypes with the above 6 loci but are resistant to BRs. These suggest that the 6 loci are defective in BR biosynthesis, and the one locus is in BR signaling. Biochemical analyses, such as intermediate feeding tests, examining the levels of endogenous BR, and molecular cloning of the genes revealed that dwf7, dwf5, and dwf1 are defective in the three consecutive steps of sterol biosynthesis, from episterol to campesterol via 5-dehydroepisterol. Similarly, det2/dwf6, dwf4, and cpd/dwf3 were Shown to be blocked in $D^4$ reduction, 22a-hydroxylation, and 23 a-hydroxylation, respectively. A signaling mutant bri1/dwf2 carries mutations in a Leucine-rich repeat receptor kinase. Interestingly, the bri1 mutant was shown to accumulate significant amount of BRs, suggesting that signaling and biosynthesis are dynamically coupled in Arabidopsis. Thus it is likely that transgenic plants over-expressing the rate-limiting step enzyme DWF4 as well as blocking its use by BRI1 could dramatically increase the biosynthetic yield of BRs. When applied industrially, BRs will boost new sector of plant biotechnology because of its potential use as a precursor of human steroid hormones, a novel lead compound for cholesterol-lowering effects, and a various application in plant protection.

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Brassinosteroid의 대사공학 (Metabolic Engineering of the Brassinosteroid Biosynthetic Pathways)

  • 이미옥;송기홍;이현경;정지윤;최빛나리;최성화
    • Journal of Plant Biotechnology
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    • 제29권2호
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    • pp.139-144
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    • 2002
  • Sterols play two major roles in plants: a bulk component in biological membranes and precursors of plant steroid hormones. Physiological effects of plant steroids, brassinosteroids (BRs), include cell elongation, cell division, stress tolerance, and senescence acceleration. Arabidopsis mutants that carry genetic defects in BR biosynthesis or its signaling display characteristic phenotypes, such as short robust inflorescences, dark-green round leaves, and sterility. Currently there are more than 100 dwarf mutants representing 7 genetic loci in Arabidopsis. Mutants of 6 loci, dwf1/dim1/cbb1, cpd/dwf3, dwf4, dwf5, det2/dwf6, dwf7 are rescued by exogenous application of BRs, whereas bri1/dwf2 shares phenotypes with the above 6 loci but are resistant to BRs. These suggest that the 6 loci are defective in BR biosynthesis, and the one locus is in BR signaling. Biochemical analyses, such as intermediate feeding tests, examining the levels of endogenous BR, and molecular cloning of the genes revealed that dwf7, dwf5, and dwf1 are defective in the three consecutive steps of sterol biosynthesis, from episterol to campesterol via 5-dehydroepisterol. Similarly, det2/dwf6, dwf4, and cpd /dwf3 were shown to be blocked in D$^4$reduction, 22a-hydroxylation, and 23 a-hydroxylation, respectively. A signaling mutant bril/dwf2 carries mutations in a Leucine-rich repeat receptor kinase. Interestingly, the bri1 mutant was shown to accumulate significant amount of BRs, suggesting that signaling and biosynthesis are dynamically coupled in Arabidopsis. Thus it is likely that transgenic plants over-expressing the rate-limiting step enzyme DWF4 as well as blocking its use by BRIl could dramatically increase the biosynthetic yield of BRs. When applied industrially, BRs will boost new sector of plant biotechnology because of its potential use as a precursor of human steroid hormones, a novel lead compound for cholesterol-lowering effects, and a various application in plant protection.

가미옥녀전(加味玉女煎)이 db/db 마우스 당뇨(糖尿)모델에서 지질대사(脂質代謝)와 항당뇨(抗糖尿) 효능(效能)에 미치는 영향(影響) (Effects of Gamiolnyeo-jeon on Lipid Metabolism and Blood Glucose Level in db/db Mice)

  • 심부용;김동희
    • 대한본초학회지
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    • 제31권2호
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    • pp.39-45
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    • 2016
  • Objectives : Abnormal regulation of glucose and impaired lipid metabolism that result from a defective or deficient insulin are the key etiological factor in type 2 diabetes mellitus. The our study investigated the effects of Gamioknyeo-jeon (GO) on blood glucose and lipid metabolism improved by it in db/db mice (a murine model of type 2 diabetes mellitus).Methods : The animals were divided into 3 groups: Normal groups were not-treated C57BL/6 mice; Control groups were treated orally with DW in db/db mice; GO groups were treated orally with GO (200 ㎎/㎏/day) in db/db mice. After mice were treated with GO for 5 weeks, we measured AST, ALT, creatinine, BUN, body weight, food intake, blood glucose, insulin and lipid levels (total cholesterol, HDL cholesterol, and LDL cholesterol and atherogenic index(AI) and cardiac risk factor(CRF).Results : Serum AST, ALT, creatinine, BUN levels were not changed by GO do not show any toxic effects. GO groups were decreased in body weight, food intake and blood glucose level among compared to Control groups. Also, GO groups were found to have atherogenic Index and cardiac risk factor as well as lipid metabolism improvement (total cholesterol and LDL cholesterol decrease). Finally, GO groups were increased the insulin compared to Normal and control groups.Conclusions : We suggest that GO may have the control effects of diabetes mellitus by improving blood glucose control and lipid metabolism.

Cytotoxic T Lymphocytes Elicited by Dendritic Cell-Targeted Delivery of Human Papillomavirus Type-16 E6/E7 Fusion Gene Exert Lethal Effects on CaSki Cells

  • Wu, Xiang-Mei;Liu, Xing;Jiao, Qing-Fang;Fu, Shao-Yue;Bu, You-Quan;Song, Fang-Zhou;Yi, Fa-Ping
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권6호
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    • pp.2447-2451
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    • 2014
  • Human papillomavirus (HPV) is the primary etiologic agent of cervical cancer. Consideration of safety and non human leukocyte antigen restriction, protein vaccine has become the most likely form of HPV therapeutic vaccine, although none have so far been reported as effective. Since tumor cells consistently express the two proteins E6 and E7, most therapeutic vaccines target one or both of them. In this study, we fabricated DC vaccines by transducing replication-defective recombinant adenoviruses expressing E6/E7 fusion gene of HPV-16, to investigate the lethal effects of specific cytotoxic T lymphocytes (CTL) against CaSki cells in vitro. Mouse immature dendritic cells (DC) were generated from bone marrow, and transfected with pAd-E6/E7 to prepare a DC vaccine and to induce specific CTL. The surface expression of CD40, CD68, MHC II and CD11c was assessed by flow cytometry (FCM), and the lethal effects of CTL against CaSki cells were determined by DAPI, FCM and CCK-8 methods. Immature mouse DC was successfully transfected by pAd-E6/E7 in vitro, and the transfecting efficiency was 40%-50%. A DC vaccine was successfully prepared and was used to induce specific CTL. Experimental results showed that the percentage of apoptosis and killing rate of CaSki cells were significantly increased by coculturing with the specific CTL (p <0.05). These results illustrated that a DC vaccine modified by HPV-16 E6/E7 gene can induce apoptosis of CaSki cells by inducing CTL, which may be used as a new strategy for biological treatment of cervical cancer.

반도체 노광 공정의 DI 세정과 Oxide의 HF 식각 과정이 실리콘 표면에 미치는 영향 (Effects of DI Rinse and Oxide HF Wet Etch Processes on Silicon Substrate During Photolithography)

  • 백정헌;최선규;박형호
    • 한국재료학회지
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    • 제20권8호
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    • pp.423-428
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    • 2010
  • This study shows the effects of deionized (DI) rinse and oxide HF wet etch processes on silicon substrate during a photolithography process. We found a fail at the wafer center after DI rinse step, called Si pits, during the fabrication of a complementary metal-oxide-semiconductor (CMOS) device. We tried to find out the mechanism of the Si pits by using the silicon wafer on CMOS fabrication and analyzing the effects of the friction charge induced by the DI rinsing. The key parameters of this experiment were revolution per minute (rpm) and time. An incubation time of above 10 sec was observed for the formation of Si pits and the rinsing time was more effective than rpm on the formation of the Si pits. The formation mechanism of the Si pits and optimized rinsing process parameters were investigated by measuring the charging level using a plasma density monitor. The DI rinse could affect the oxide substrate by a friction charging phenomenon on the photolithography process. Si pits were found to be formed on the micro structural defective site on the Si substrate under acceleration by developed and accumulated charges during DI rinsing. The optimum process conditions of DI rinse time and rpm could be established through a systematic study of various rinsing conditions.

세로 검은 줄무늬가 없는 전하 결합 소자의 설계 (Design of a Charge-Coupled Device without Vertical Black Stripes)

  • 박용;이영희
    • 한국정보처리학회논문지
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    • 제4권4호
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    • pp.1100-1105
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    • 1997
  • 세로 검은 줄무늬 전하 결합 소자 결점의 하나이다. 세로 검은 줄무늬는 수직 전하 전송부에서 수평 전하 전송부로 넘어가지 못하는 신호 전하량에 의하여 나타난 것이다. 신호 전하의 불완전한 전송은 수직-수평 채널 경계 영역 구조에서 좁은 폭 효과에 의하여 발생한 전위 장벽 때문이다. 세로 검은 줄무늬는 저 조도하에서 전하 전송 효율이 99.2% 이하로 전송될 때 나타난다. 본 논문은 새로운 수직-수평 채널 경계 영역 구조를 전위 장벽이 발생하지 않도록 부채꼴 형태로 설계 제작하여 세로 검은 줄무늬를 제거하였다.

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타격음 주파수 분석법에 의한 원통 병렬 구조물의 파손 여부 식별에 관한 연구 (A Study on the Detection of Defects from Parallel Cylindrical Objects Using Spectral Analysis of Acoustic Impact Signal)

  • 방호균;조철우
    • 한국음향학회지
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    • 제14권4호
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    • pp.12-20
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    • 1995
  • 본 논문은 충격 음향법에 의한 원통형 물체의 결함 검출 방법에 관한 원리와 실험 결과를 기술한다. 원통형 물체가 가지게 되는 공진 주파수는 물체의 직경, 길이 등의 물리적 크기에 따라 결정되며 이러한 원통형 물체를 자유 공진 시킬 경우 구조물 고유에 주파수 및 고조파 성분이 내포된 음향을 방생시킨다. 결함이 존재하는 물체에 충격ㄷ이 가해질 경우 발생하는 음향은 정상의 경우와 구별되며, 주파수 성분 분석을 통해 보다 명확한 식별이 가능하다. 본 연구에서 적용된 음향 충격법에 의한 결함 검출 기법은 연구 대상 물체의 경우 결함 유무를 완벽하게 판정할 수 있었으며, 차후 유사한 형태의 구조물에 대한 결함 검출에도 응용될 수 있다.

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인터넷 쇼핑몰 불만족 요인이 불평행동과 중재제도 이용의도에 미치는 영향에 관한 연구 (A Study on the Effects of Internet Shopping Mall Dissatisfaction Factors on Complaint Behavior and Intention to Use Arbitration System)

  • 이재학;박철희
    • 한국중재학회지:중재연구
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    • 제30권2호
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    • pp.145-164
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    • 2020
  • With the development of the Internet, e-commerce is rapidly developing, and e-commerce through the Internet has become a major distribution channel for selling products and services to consumers and buyers. However, as Internet shopping develops, consumer dissatisfaction and conflict are increasing. In this regard, this study examined how consumer dissatisfaction caused by using an Internet shopping mall, which is currently taking the core position in commerce activities, leads to consumer complaints, and how these complaints affect the necessity and intention to use the arbitration system. As a result of the study, the following implications were obtained. First, it will be necessary to remove the root cause of consumer complaints by continuously monitoring consumer complaints, rather than staying at passive consumer complaints such as defective product exchange and damage compensation for dissatisfaction with Internet shopping malls. Second, it can be said that the function of the arbitration system is required to protect the rights and interests of consumers using the Internet shopping mall and to actively improve the problems in the event of a damage situation or a problem situation. Lastly, academia's continuous research will be needed, and governments and related organizations will need to continuously provide and promote information to users of Internet shopping malls.

The phosphoinositide-specific phospholipase C gene, MPLCl, of Magnaporthe grisea is required for fungal development and plant colonization

  • Park, Hee-Sool;Lee, Yong-Hwan
    • 한국식물병리학회:학술대회논문집
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    • 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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    • pp.84.1-84
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    • 2003
  • Magnaporthe grisea, the casual agent of rice blast, forms an appressorium to penetrate its host. Much has been learned about environmental cues and signal transduction pathways, especially those involving CAMP and MAP kinases, on appressorium formation during the last decade. More recently, pharmacological data suggest that calcium/calmodulin-dependent signaling system is involved in its appressorium formation. To determine the role of phosphoinositide-specific phospholipase C (PI-PLC) on appressorium formation, a gene (WPLCl) encoding PI-PLC was cloned and characterized from M. grisea strain 70-15. Sequence analysis showed that MPLCl has alt five conserved domains present in other phospholipase C genes from several filamentous fungi and mammals. Null mutants (mplcl) generated by targeted gene disruption exhibited pleiotropic effects on conidial morphology, appressorium formation, fertility and pathogenicity. mplcl mutants developed nonfunctional appressoria and are also defective in infectious growth in host tissues. Defects in appressorium formation and pathogenicity in mplcl mutants were complemented by a mouse PLCdelta-1 cDNA under the control of the MPLCl promoter. These results suggest that cellular signaling mediated by MPLCl plays crucial and diverse roles in development and pathogenicity of M. grisea, and functional conservation between fungal and mammalian Pl-PLCs.

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Efficient Use of Unused Spare Columns for Reducing Memory Miscorrections

  • Jung, Ji-Hun;Ishaq, Umair;Song, Jae-Hoon;Park, Sung-Ju
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제12권3호
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    • pp.331-340
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    • 2012
  • In the deep sub-micron ICs, growing amounts of on-die memory and scaling effects make embedded memories increasingly vulnerable to reliability and yield problems. Spare columns are often included in memories to repair defective cells or bit lines during production test. In many cases, the repair process will not use all spare columns. Schemes have been proposed to exploit these unused spare columns to store additional check bits which can be used to reduce the miscorrection probability for triple errors in single error correction-double error detection (SEC-DED). These additional check bits increase the dimensions of the parity check matrix (H-matrix) requiring extra area overhead. A method is proposed in this paper to efficiently fill the extra rows of the H-matrix on the basis of similarity of logic between the other rows. Optimization of the whole H-matrix is accomplished through logic sharing within a feasible operating time resulting in reduced area overhead. A detailed implementation using fuse technology is also proposed in this paper.