• 제목/요약/키워드: 7a

검색결과 145,254건 처리시간 0.113초

Cosuppression and RNAi induced by Arabidopsis ortholog gene sequences in tobacco

  • Oka, Shin-Ichiro;Midorikawa, Kaoru;Kodama, Hiroaki
    • Plant Biotechnology Reports
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    • 제4권3호
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    • pp.185-192
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    • 2010
  • The Arabidopsis ${\omega}$-3 fatty acid desaturase (AtFAD7) catalyzes the synthesis of trienoic fatty acids (TA). A transgenic tobacco line, T15, was produced by a sense AtFAD7 construct and showed a cosuppression-like phenotype, namely extremely low TA levels. The sequence similarity between AtFAD7 and a tobacco ortholog gene, NtFAD7, was moderate (about 69%) in the coding sequences. AtFAD7 siRNAs accumulated at a high level, and both AtFAD7 and NtFAD7 mRNAs are degraded in T15 plants. The low-TA phenotype in T15 was dependent on a tobacco RNA-dependent RNA polymerase6 (NtRDR6). We also produced tobacco RNAi plants targeting AtFAD7 gene sequences. The AtFAD7 siRNA level was trace, which was associated with a slight reduction in leaf TA level. Unexpectedly, this RNAi plant showed an increased NtFAD7 transcript level. To investigate the effect of translational inhibition on stability of the NtFAD7 mRNAs, leaves of the wild-type tobacco plants were treated with a translational inhibitor, cycloheximide. The level of NtFAD7 mRNAs significantly increased after cycloheximde treatment. These results suggest that the translational inhibition by low levels of AtFAD7 siRNAs or by cycloheximide increased stability of NtFAD7 mRNA. The degree of silencing by an RNAi construct targeting the AtFAD7 gene was increased by co-existence of the AtFAD7 transgene, where NtRDR6-dependent amplification of siRNAs occurred. These results indicate that NtRDR6 can emphasize silencing effects in both cosuppression and RNAi.

분산형 레이어 7 서버 부하 분산 (A Distributed Layer 7 Server Load Balancing)

  • 권희웅;곽후근;정규식
    • 정보처리학회논문지A
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    • 제15A권4호
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    • pp.199-210
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    • 2008
  • 무선 인터넷 프록시 서버 클러스터링에서 저장공간을 최소화하기 위해서는 URL 해싱기법을 가진 Layer 7 부하분산기가 필요하다. 서버 클러스터 앞단에 위치한 Layer 4 부하분산기는 TCP 또는 UDP와 같은 트랜스포트 계층에서 컨텐츠 내용을 확인하지 않고 사용자 요청들을 똑같은 컨텐츠를 가진 서버들에게 분배한다. 서버 클러스터 앞단에 위치한 Layer 7 부하분산기는 응용계층에서 사용자 요청을 분석하여 요청 컨텐츠 유형에 따라 해당되는 서버들에게 분배한다. Layer 7 부하분산기를 이용하면 서버들이 배타적으로 각기 다른 컨텐츠를 가지게 할 수 있어서 서버들 저장공간을 최소화할 수 있으며 전체 클러스터 성능을 향상할 수 있다. 그러나 Layer 7 부하분산기는 응용계층에서 사용자 요청을 분석하는데 요구되는 큰 처리 부담으로 인해 Layer 4 부하분산기와 다르게 확장성이 제한된다. 본 논문에서는 그 확장성 제한을 극복하기 위해서 분산형 Layer 7 부하분산기를 제안한다. 종래의 방법에서는 한 대의 Layer 7 부하분산기 를 사용하는데 본 논문에서 제안한 방법에서는 서버 클러스터 앞에 한 대의 Layer 4 부하분산기를 설치하고 서버들에게 Layer 7 부하분산기들을 각각 설치한다. 클러스터 기반의 무선 인터넷 프록시 서버에서 종래의 방법을 리눅스기반의 Layer 7 부하분산기인 KTCPVS를 이용하여 구현하였다. 본 논문에서 제안한 방법에서는 리눅스기반의 Layer 4 부하분산기인 IPVS를 사용하고 각 서버들에게 Layer 7 부하분산기인 KTCPVS를 설치하여 같이 동작하게 구현하였다. 실험은 16대의 컴퓨터를 사용하여 수행되었고, 실험 결과에 의하면 제안 방법이 종래 방법에 비해 서버 대수가 증가함에 따라 확장성 및 높은 성능 향상률을 가짐을 확인하였다.

C7 Fracture as a Complication of C7 Dome-Like Laminectomy : Impact on Clinical and Radiological Outcomes and Evaluation of the Risk Factors

  • Yang, Seung Heon;Kim, Chi Heon;Lee, Chang Hyun;Ko, Young San;Won, Youngil;Chung, Chun Kee
    • Journal of Korean Neurosurgical Society
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    • 제64권4호
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    • pp.575-584
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    • 2021
  • Objective : Cervical expansive laminoplasty is an effective surgical method to address multilevel cervical spinal stenosis. During surgery, the spinous processes of C2 and C7 are usually preserved to keep the insertion points of the cervical musculature and nuchal ligament intact. In this regard, dome-like laminectomy (undercutting of C7 lamina) instead of laminoplasty is performed on C7 in selected cases. However, resection of the lamina can weaken the C7 lamina, and stress fractures may occur, but this complication has not been characterized in the literature. The objective of the present study was to investigate the incidence and risk factors for C7 laminar fracture after C7 dome-like laminectomy and its impact on clinical and radiological outcomes. Methods : Patients who underwent cervical open-door laminoplasty combined with C7 dome-like laminectomy (n=123) were classified according to the presence of C7 laminar fracture. Clinical parameters (neck/arm pain score and neck disability index) and radiologic parameters (C2-7 angle, C2-7 sagittal vertical axis, and C7-T1 angle) were compared between the groups preoperatively and at postoperatively at 3, 6, 12, and 24 months. Risk factors for complications were evaluated, and a formula estimating C7 fracture risk was suggested. Results : C7 lamina fracture occurred in 32/123 (26%) patients and occurred at the bilateral isthmus in 29 patients and at the spinolaminar junction in three patients. All fractures appeared on X-ray within 3 months postoperatively, but patients did not present any neurological deterioration. The fracture spontaneously healed in 27/32 (84%) patients at 1 year and in 29/32 (91%) at 2 years. During follow-up, clinical outcomes were not significantly different between the groups. However, patients with C7 fractures showed a more lordotic C2-7 angle and kyphotic C7-T1 angle than patients without C7 fractures. C7 fracture was significantly associated with the extent of bone removal. By incorporating significant factors, the probability of C7 laminar fracture could be assessed with the formula 'Risk score = 1.08 × depth (%) + 1.03 × length (%, of the posterior height of C7 vertebral body)', and a cut-off value of 167.9% demonstrated a sensitivity of 90.3% and a specificity of 65.1% (area under the curve, 0.81). Conclusion : C7 laminar fracture can occur after C7 dome-like laminectomy when a substantial amount of lamina is resected. Although C7 fractures may not cause deleterious clinical outcomes, they can lead to an unharmonized cervical curvature. The chance of C7 fracture should be discussed in the shared decision-making process.

고초균을 이용한 재조합 인간 골 형성 단백질-7의 발현과 정제 (Expression and Purification of Recombinant Human Bone Morphogenetic Protein-7 (rhBMP-7) in Bacillus subtilis)

  • 김춘광;오성덕;이종일
    • KSBB Journal
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    • 제25권3호
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    • pp.257-264
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    • 2010
  • Bone morphogenetic protein-7 (BMP-7) is one of important growth factors for skeletal development and bone growth. In this work, BMP-7 was efficiently expressed in recombinant Bacillus subtilis. The mature BMP-7 protein indicated molecular weight of 15.4 kDa by Western blot assay and was secreted into culture medium with 0.35 ng/mL. The extracellular and intracellular rhBMP-7 proteins were purified by using a FPLC system with an ion exchange column and a gel filtration column. The extracellular and intracellular rhBMP-7 proteins had finally a 57.1% purity and a 36.2% purity, respectively. The purified rhBMP-7 proteins showed an intact biological activity which stimulated alkaline phophatase (ALP) activity in MC3T3-E1 cells.

Singlet-Triplet Reactivity of 1-Methyl-2-Cyclohexenyl Aryl Ketones : Racemization vs 1,3-Acyl Shift in the Excited States

  • Woo Ki Chae;Mi Young Chae;Mi Kyung Park;Chung Hee Lee;Eun Hee You
    • Bulletin of the Korean Chemical Society
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    • 제11권3호
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    • pp.241-244
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    • 1990
  • The photochemistry of 1-Methyl-2-cyclohexenyl aryl ketones (phenyl ketone 7a, p-toluyl ketone 7b, biphenyl ketone 7c and -naphthyl ketone 7d) is reported. The aryl ketone 7a, 7b and 7c undergo photo-racemization with efficiencies of 0.75, 0.79 and 0.76 respectively on direct irradiation. Direct irradiation of the ketone 7d, however, undergoes 1,3-shift with an efficiency of 0.02. Triplet states are responsible for the racemizations and singlet state is responsible for 1,3-shift as in general. The ketone 7a, 7b and 7c are good example of a few ${\beta},{\gamma}$-unsaturated ketones which undergo efficient intersystem crossing on direct irradiation.

클로람페니콜 내성 플라스미드 pKH7의 Pre 단백질의 염기서열 결정 (Nucleotide Sequence of Pre Protein in Chloramphenicol Resistance Plasmid pKH7.)

  • 문경호;박봉동;이동석;이백락
    • 한국미생물·생명공학회지
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    • 제26권6호
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    • pp.566-568
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    • 1998
  • Partial nucleotide sequence (nt 1-1842) of chloramphenicol resistance plasmid pKH7 has been reported previously and residual nucleotide sequence (nt 1843-4118) of pKH7 was determined and then the complete nucleotide sequence of pKH7 was obtained. pKH7 consists of 4118 bp and has three ORFs. Besides Rep and CAT proteins described in previous paper, Pre protein which mediates site-specific recombination in Staphylococcus aureus was found to be on pKH7. R $S_{A}$, a site-specific recombination site of Pre protein, and palA, a specific lagging-strand conversion signal, was also found in pKH7. Amino acid sequence of Pre protein of pKH7 was compared with those of other antibiotic resistant Staphylococcus aureus plasmids.s.

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7가 페구균백신 접종에도 치명적인 폐구균 19A 수막염 1예 (A case of fatal pneumococcal 19A meningoencephalitis despite administration of seven-valent pneumococcal conjugate vaccines)

  • 허아름;이준화
    • Clinical and Experimental Pediatrics
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    • 제52권4호
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    • pp.508-511
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    • 2009
  • 폐구균(Streptococcus pneumoniae)은 소아, 특히 어린 영아에서 심한 침습성 질병을 일으키는 중요한 원인균이다. 2003년부터 우리나라에서 접종하기 시작한 7가 폐구균백신(PCV7)은 소아에서 침습성 폐구균성 폐렴과 수막염을 예방하는 것으로 알려져 왔다. 그러나 최근 7가 폐구균백신을 접종한 이후부터 비7가 폐구균 혈청형(non-PCV7 serotype) 감염 발생률이 증가하고 있다. 14개월 된 여아가 내원 3일 전부터 열과 구토가 있었으나 증상 치료만 하고 있던 중 갑작스런 의식불명과 기면(lethargy)으로 응급실로 내원하였다. 입원 후 즉각적인 진단과 치료를 시행했음에도 불구하고 환자는 빠르게 혼수와 뇌사 상태로 진행하였다. 환자는 이전에 3회의 7가 폐구균백신을 접종하였으나 최종 진단은 비7가 폐구균 혈청형인 폐구균 19A 수막염이었고, 입원 20일째 사망하였다. 이는 한국에서 문헌상 보고된 적이 없는, 폐구균 19A 혈청형 수막염으로 사망한 첫번째 증례이므로 이에 보고하는 바이다.

Unique epithelial expression of S100A calcium binding protein A7A in the endometrium at conceptus implantation in pigs

  • Lee, Soohyung;Jang, Hwanhee;Yoo, Inkyu;Han, Jisoo;Jung, Wonchul;Ka, Hakhyun
    • Asian-Australasian Journal of Animal Sciences
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    • 제32권9호
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    • pp.1355-1362
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    • 2019
  • Objective: S100A7A, a member of the S100 protein family, is involved in various biological processes, including innate immunity, antimicrobial function, and epithelial tumorigenesis. However, the expression and function of S100A7A in the endometrium during the estrous cycle and pregnancy are not well understood in pigs. Therefore, this study determined the expression and regulation of S100A7A at the maternal-conceptus interface in pigs. Methods: We obtained endometrial tissues from pigs throughout the estrous cycle and pregnancy, conceptus tissues during early pregnancy, and chorioallantoic tissues during midto late pregnancy and analyzed the expression of S100A7A in these tissues. We also determined the effects of steroid hormones, estradiol-$17{\beta}$ ($E_2$) and progesterone, and interleukin-$1{\beta}$ (IL1B) on S100A7A expression in endometrial tissues. Results: We found that S100A7A was expressed in the endometrium during the estrous cycle and pregnancy in a pregnancy status- and stage-dependent manner and was localized to endometrial luminal epithelial (LE) and superficial glandular epithelial cells with strong intensity in LE cells on day 12 of pregnancy. Early stage conceptuses and chorioallantoic tissues from day 30 to term pregnancy also expressed S100A7A. The expression of S100A7A was increased by $E_2$ and IL1B in endometrial tissues. Conclusion: S100A7A was expressed at the maternal-conceptus interface at the initiation of implantation in response to conceptus-derived estrogen and IL1B and could be a unique endometrial epithelial marker for conceptus implantation in pigs. These findings provide an important insight into the understanding of conceptus-endometrial interactions for the successful establishment of pregnancy in pigs.

A study on analysis of 7-Eleven's competition structure and competitiveness using Porter's 5 Force model

  • Kwang-Keun LEE
    • International Journal of Advanced Culture Technology
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    • 제12권1호
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    • pp.202-208
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    • 2024
  • Objective: The purpose of this study is to examine the competitive environment of 7-Eleven using Porter's 5 Force model to analyze the specific competitiveness of 7-Eleven that has maintained continuous growth as a competitive company. Methods: This study is a case study of 7-Eleven. Results: As a result of the analysis, 7-Eleven has reinforced its competitiveness with existing competitors by raising entry barriers by expanding domestic stores and developing overseas convenience store business, focusing on North America, based on economy of scale. In addition, 7-Eleven seeks to differentiate itself from other convenience stores by developing a "private brand" and strengthens its bargaining power with suppliers through the development of new products by gathering information and know-how of experts in product development based on customer needs. The bargaining power with customers has been strengthened by building loyalty and trust in the brand by allowing consumers to purchase the same products at the same price no matter which store they visit. As a threat to potential competitors, 7-Eleven has secured a competition advantage by raising the barrier to entry by concentrating stores in specific areas through a dominant franchise development strategy and increasing awareness of 7-Eleven among consumers. In the case of threats from substitute products, it was confirmed that 7-Eleven has overcome the threat from substitute products by opening 24 hours a day and providing various services such as ATMs and copiers.

Transforming Stimulated Clone 22 (TSC-22) Interacts Directly with Bromodomain-Containing Protein 7 (BRD7) to Enhance the Inhibition of Extracellular Signal-Regulate Kinase (ERK) Pathway in Ovarian Cancer

  • Lee, Seung-Hoon;Choi, Donchan
    • 한국발생생물학회지:발생과생식
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    • 제26권3호
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    • pp.117-126
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    • 2022
  • Bromodomain-containing protein 7 (BRD7) participates in many cellular processes and embryo development. BRD7 is down-regulated in various cancers and evidence of its tumor suppressor function has been accumulating. Here, we identified transforming stimulated clone 22 (TSC-22) as a novel BRD7 interacting protein and show its novel function as a positive regulator of BRD7. We found that TSC-22 expression potentiated the inactivation of the extracellular signal-regulate kinase (ERK) pathway by BRD7. Our data establishes TSC-22 as a modulator of BRD7 and unravels the molecular mechanisms that drive the synergistic tumor-suppressing effects of TSC-22 and BRD7. Our findings may open new avenues for developing novel molecular therapies for tumors exhibiting down-regulated BRD7 and/or TSC-22.