• Title/Summary/Keyword: MSR

Search Result 173, Processing Time 0.025 seconds

Expression, subcellular localization, and antioxidant role of mammalian methionine sulfoxide reductases in Saccharomyces cerevisiae

  • Kwak, Geun-Hee;Kim, Jae-Ryong;Kim, Hwa-Young
    • BMB Reports
    • /
    • v.42 no.2
    • /
    • pp.113-118
    • /
    • 2009
  • Despite the growing body of evidence suggesting a role for MsrA in antioxidant defense, little is currently known regarding the function of MsrB in cellular protection against oxidative stress. In this study, we overexpressed the mammalian MsrB and MsrA genes in Saccharomyces cerevisiae and assessed their subcellular localization and antioxidant functions. We found that the mitochondrial MsrB3 protein (MsrB3B) was localized to the cytosol, but not to the mitochondria, of the yeast cells. The mitochondrial MsrB2 protein was detected in the mitochondria and, to a lesser extent, the cytosol of the yeast cells. In this study, we report the first evidence that MsrB3 overexpression in yeast cells protected them against $H_2O_2$-mediated cell death. Additionally, MsrB2 overexpression also provided yeast cells with resistance to oxidative stress, as did MsrA overexpression. Our results show that mammalian MsrB and MsrA proteins perform crucial functions in protection against oxidative stress in lower eukaryotic yeast cells.

Prevention of Buffer Overflow in the Mobility Support Router for I-TCP (I-TCP를 위한 이동성 지원 라우터에서의 버퍼 오버플로우 방지)

  • 김창호;최학준;장주욱
    • Journal of KIISE:Information Networking
    • /
    • v.31 no.1
    • /
    • pp.20-26
    • /
    • 2004
  • A congestion control algorithm to prevent buffer overflow in MSR(Mobility Support Router) for I-TCP is proposed. Due to high bit error rate and frequent hand-offs over wireless environment, the current congestion control scheme in TCP Reno over mixed(wired and wireless) network exhibits lower throughput than the throughput achieved over wired only network. I-TCP has been proposed to address this by splitting a TCP connection into two TCP connections over wired section and wireless section, respectively. However, buffer overflow in MSR may occur whenever there are excessive bit errors or frequent hand-offs. This may lead to the loss of packets acked by MSR(resident in buffer) to the sender, but not received by the receiver, breaking TCP end-to-end semantics. In this Paper, a new scheme is proposed to prevent the MSR buffer from overflow by introducing “flow control” between the sender and the MSR. Advertised window for the TCP connection between the sender and the MSR is tied to the remaining MSR buffer space, controlling the flow of packets to the MSR buffer before overflow occurs.

Inhibition of methionine sulfoxide reduction by dimethyl sulfoxide

  • Kwak, Geun-Hee;Choi, Seung-Hee;Kim, Jae-Ryong;Kim, Hwa-Young
    • BMB Reports
    • /
    • v.42 no.9
    • /
    • pp.580-585
    • /
    • 2009
  • Dimethyl sulfoxide (DMSO) is widely used in chemistry and biology as a solvent and as a cryoprotectant. It is also used as a pharmaceutical agent for the treatment of interstitial cystitis and rheumatoid arthritis. Previous reports described DMSO as being reduced by methionine-S-sulfoxide reductase (MsrA). However, little is known about the DMSO reduction capability of methionine-R-sulfoxide reductase (MsrB) or its effect on the catalysis of methionine sulfoxide reduction. We show that mammalian MsrB2 and MsrB3 were unable to reduce DMSO. This compound inhibited MsrB2 activity but did not inhibit MsrB3 activity. We further determined that DMSO functions as an inhibitor of MsrA and MsrB2 in the reduction of methionine sulfoxides via different inhibition mechanisms. DMSO competitively inhibited MsrA activity but acted as a non-competitive inhibitor of MsrB2 activity. Our study also demonstrated that DMSO inhibits in vivo methionine sulfoxide reduction in yeast and mammalian cells.

Deterioration of Agronomic Characteristics of Drought-Resistant GM Rice (CaMsrB2-8) (가뭄저항성 GM벼(CaMsrB2-8)의 농업적 특성의 퇴화 가능성 검정)

  • Kim, Bo-Ra;Son, Jin-Hwan;Kim, Hye-Ryun;Ham, Jung-Kwan;Dhungana, Sanjeev Kumar;Park, Soon-Ki;Shin, Dong-Hyun
    • Weed & Turfgrass Science
    • /
    • v.2 no.2
    • /
    • pp.159-163
    • /
    • 2013
  • The purpose of this study is to observe the growth habit and investigate a possibility of cultivating the GM rice (CaMsrB2-8) as a rice cultivar having drought resistance. Germination viability test showed that there was no significant difference between the drought-resistant GM(CaMsrB2-8) and non-GM (Ilmi) rice which was the parent variety at the GM rice. All the seeds of CaMsrB2-8 and Ilmi germinated after 6 days. Viviparous germination was not found in CaMsrB2-8 and Ilmi that was grown in greenhouse at $23{\pm}2^{\circ}C$ with water spraying for 40 days. Ratooning of CaMsrB2-8 and Ilmi was observed in 7-14 days and found uniform in field condition. CaMsrB2-8 seemed to grow faster than Ilmi. But CaMsrB2-8 and Ilmi were similar in 14-21 days. Both CaMsrB2-8 and Ilmi showed low seed shattering and more than 90% grains were ripened. All the seeds scattered in the paddy soil surface were not germinated after passing the winter. This study suggests that the drought-resistant GM rice was not significantly different with the parent variety of Ilmi in many agronomic characteristics such as wildness traits.

A Study on the Implementation of a Web-browser-based Global e-Navigation Service Discovery System for Decentralized Maritime Service Registries (탈중앙화 MSR 환경에서의 웹 브라우저 기반 글로벌 이내비게이션 서비스 검색 시스템 구현에 대한 연구)

  • Jinki, Jung;Young-Joong, Ahn
    • Journal of Navigation and Port Research
    • /
    • v.46 no.6
    • /
    • pp.501-508
    • /
    • 2022
  • The flow of global digitalization is leading to the emergence of a decentralized system environment based on blockchain or distributed ledger technology in the fields of economy, identity authentication, and logistics. Accordingly, a requirement that public services be searchable from several decentralized maritime service registries (MSRs) has been derived in terms of the discoverability of e-navigation services. This study describes a decentralized MSR environment composed of the MSR ledger and multiple local MSRs, and it has implemented a service search system that can search global e-navigation services in the environment through a web browser. This system is a decentralized application that dynamically generates service attributes, geometry information, and free text queries, and that provides users with relevant MSR and service access information from search results that are registered in the MSR ledger. In this study, we tested the established decentralized MSR environment and the system that performs service search within that environment, and we discussed its advantages and limitations.

A Study on the Implications of the MSR Standards for the Development of Records Management Practice in Korea (기록경영시스템(MSR) 표준 제정에 대비한 기록관리의 발전과제에 관한 연구)

  • Jeong, Ki-Ae
    • Journal of Korean Society of Archives and Records Management
    • /
    • v.10 no.2
    • /
    • pp.171-192
    • /
    • 2010
  • In this study, the concepts and main ideas of the 'Management System for Records(MSR)' standards which is being prepared by ISO(TC46/SC11) are explained. And the implications and prospects of MSR standards are suggested for the development of records management practice in Korea. The MSR has the same frame with the ISO 9001(QA system) and its main procedures are consistent with ISO 15489. Its methodology of record management can help organizations to integrate their records management with their own management and system development strategies. The MSR can provide good solutions to improve the national archiving policy and to solve the current argument about the professionalism of record managers.

Improvement Direction of the Public Records Management System for the Application of MSR (Management System for Records) (기록경영시스템(MSR) 적용에 대비한 공공기관 기록관리 제도의 개선 방향)

  • Kang, Dongkyun;Rieh, Hae-Young
    • Journal of Korean Society of Archives and Records Management
    • /
    • v.16 no.4
    • /
    • pp.121-148
    • /
    • 2016
  • MSR identifies that records are key factors in achieving the goals of an organization and that records management is part of the business administration. Therefore, organizations could secure accountability and continuity of works through the activities of production and management records. This study explored what should be prepared to adopt MSR in public institutions based on the analysis of the requirements of the ISO 30301. which is prepared to be utilized as a certificate system. It focuses on 1) how laws could be supplemented to adopt MSR by comparing the requirements of MSR and the Public Records Management Act; 2) what should be prepared by organizations in terms of their rules and procedures; and 3) how the evaluation system of public institutions and the records management evaluation system could be revised to ensure that MSR will be sufficiently implemented in the organizations. In conclusion, the part to be supplemented by the law, the area to be operated as the internal rules of the organizations, and the way to be reflected in the evaluation of the public institutions were suggested.

Mechanical Stress Relief Technology and its Application (MSR을 이용한 용접잔류응력의 제거와 적용성 검토)

  • 박지선;한명수;한종만
    • Journal of Welding and Joining
    • /
    • v.15 no.3
    • /
    • pp.29-35
    • /
    • 1997
  • 실제로 용접구조물의 재료에는 항상 내부 잔류응력이 존재하며 그 크기는 재료내의 내부 잔류응력간의 평형의 원리(Self-equilibrating system)에 의해 결정 된다. 일반적인 구조 강도설계에서 행해지는 탄성해석에서는 재료 내부에 존재하는 잔류응력을 고려하지 않기 때문에 설계시에 계산된 응력이 심하중하의 구조물에서 발생하는 응력과 같다고 볼 수는 없다. 철강재료를 사용한 구조물의 경우 구조물 제작 공정 전반에 걸친 성형가공 및 조립과정에 수반되어 재료 내에는 잔류응력이 발생되며 특히 용접조립에 의해 용접부 근방에서는 재료의 항복강도 수준의 상당히 큰 용접응력 이 발생하게 된다. 일반적으로 용접잔류응력의 완화법으로 가장 확실한 방법은 후열 처리법(Post weld heat treatment, PWHT)이지만 이 방법의 적용은 구조물의 크기에 제한을 받게 된다. 따라서 PWHT를 적용하기 어려운 구조물에 대해서는 다른 방법에 의해 용접잔류 응력을 완화시켜야 하며 이 경우에 일반적인 방법으로 기계적 응력완화 법(Mechanical stress relief method, MSR)이 있다. 본고에서는 MSR의 기본원리에 대하여 간단하게 정리하고 실 구조물에 대한 MSR 적용시 고려해야 할 제반사항을 위하여 단순 용접부에 대한 MSR 적용 실험결과와 실제 압력용기를 대상으로 MSR을 자체 제작된 기술절차서에 따라서 시행하고 MSR의 적용성에 대해서 검토하였다.

  • PDF

기계적인 잔류응력 이완방법의 원리와 기계적 성질에 미치는 영향

  • 김용완;김희진
    • Journal of Welding and Joining
    • /
    • v.5 no.2
    • /
    • pp.1-8
    • /
    • 1987
  • MSR 처리를 실제구조물에 적용하기 위해서 잔류응력과 기계적성질에 대하여 조사해 본 결과 다음의 결론을 얻었다. (1) MSR 처리는 소성변형을 유발시켜 높은 인장잔류응력을 감소시키는데 유효하며, 잔류응력이 낮은 부위에 대해서는 잔류응력 재배치에 따른 응력치의 변화가 수반된다. (2) 잔류응력 감소량은 MSR 하중에 비례하여 증가 한다. (3) 모재의 항복응력보다 낮은 하중으로 MSR 처리를 하면 충격치의 감소는 무시할 정도이지만 모재의 항복응력보다 높은 하중으로 행하면 응착금속에서 충격치의 감소가 현저하다. (4) MSR 처리를 하게되면 항복응력이 높아지고, 잔류응력이 감소해서 선형의 응력-스트레인의 관계를 가지는 범위가 넓어져서 구조적으로 안전한 상태가 된다.

  • PDF

The protein truncation caused by fusion of PEP-1 peptide and protective roles of transduced PEP-1-MsrA in skin cells

  • Lee, Tae-Hyung;Choi, Seung-Hee;Kim, Hwa-Young
    • BMB Reports
    • /
    • v.44 no.4
    • /
    • pp.256-261
    • /
    • 2011
  • PEP-1 peptide has been used for transduction of native protein into mammalian cells. This work describes the findings that the fusion of PEP-1 to target proteins led to protein truncation likely in a non-protein-specific manner. Approximately 75% of PEP-1-MsrA fusion protein was truncated in the N-terminal region of MsrA between Lys-27 and Val-28 during expression in Escherichia coli and purification. This large protein truncation was also observed in another PEP-1 fused protein, PEP-1-MsrB2, in the N-terminal region of MsrB2. The full-length PEP-1-MsrA protein was rapidly transduced into keratinocyte cells within 15 min. The transduced PEP-1-MsrA was functionally active and could protect skin cells against oxidative stress- and ultraviolet radiation-induced cell death. Collectively, our data demonstrated the protective roles of MsrA in skin cells and, moreover, may raise a concern of protein truncation caused by fusion of PEP-1 about the general use of this peptide for protein transduction.