• 제목/요약/키워드: Host Defense

검색결과 296건 처리시간 0.023초

전자서명을 이용한 스미싱 공격 방어 기법 (Defense Techniques of Smishing Attacks Using Electronic signature on Network Environment)

  • 최병환
    • 한국정보처리학회:학술대회논문집
    • /
    • 한국정보처리학회 2014년도 추계학술발표대회
    • /
    • pp.399-402
    • /
    • 2014
  • 본 논문에서는 스미싱 공격에 대해서 Host기반에 의한 탐지가 아닌 네트워크 기반에서 전자서명을 이용한 모델을 제안한다. 본 모델은 네트워크 기반에서 유입된 트래픽 중 문자 메시지를 분석하여, 문자메시지 중에서 URL이 포함된 경우 트래픽을 우회하여 라우팅을 전환시켜 URL을 포함한 문자메시지 트래픽에 대해서 별도의 망구간으로 분리를 시킨다. 별도 분리된 URL이 포함된 트래픽에 대해서 apk파일 다운로드가 없는 경우에는 통과를 시키고, apk 파일 다운로드를 시도하는 트래픽에 대해서는 전자서명을 검사후, 등록이 안되어 있는 경우 차단을 한다. 이는 기본적으로 전자서명이 되지 않은 apk파일에 대한 다운로드를 원천적으로 봉쇄함으로써 스미싱 공격에 대한 근복적인 방어를 하는 방식이다. 본 모델은 Host기반에서 발생할 수 있는 우회공격을 방지하여 스미싱 위협을 해소할 수 있다. 기존 Host기반 스미싱 방지 모델의 동작 방식과 설계를 통해 장점과 단점을 언급하고 네트워크 기반에서 전자서명을 이용한 스미싱 방어의 타당성을 증명하도록 한다.

Exploring Staphylococcus aureus Virulence Factors; Special Emphasis on Staphyloxanthin

  • Yehia, Fatma Al-zahraa A.;Yousef, Nehal;Askoura, Momen
    • 한국미생물·생명공학회지
    • /
    • 제49권4호
    • /
    • pp.467-477
    • /
    • 2021
  • Staphylococcus aureus is a well-known pathogen that can cause diseases in humans. It can cause both mild superficial skin infections and serious deep tissue infections, including pneumonia, osteomyelitis, and infective endocarditis. To establish host infection, S. aureus manages a complex regulatory network to control virulence factor production in both temporal and host locations. Among these virulence factors, staphyloxanthin, a carotenoid pigment, has been shown to play a leading role in S. aureus pathogenesis. In addition, staphyloxanthin provides integrity to the bacterial cell membrane and limits host oxidative defense mechanisms. The overwhelming rise of Staphylococcus resistance to routinely used antibiotics has necessitated the development of novel anti-virulence agents to overcome this resistance. This review presents an overview of the chief virulence determinants in S. aureus. More attention will be paid to staphyloxanthin, which could be a possible target for anti-virulence agents.

Computational approaches for prediction of protein-protein interaction between Foot-and-mouth disease virus and Sus scrofa based on RNA-Seq

  • Park, Tamina;Kang, Myung-gyun;Nah, Jinju;Ryoo, Soyoon;Wee, Sunghwan;Baek, Seung-hwa;Ku, Bokkyung;Oh, Yeonsu;Cho, Ho-seong;Park, Daeui
    • 한국동물위생학회지
    • /
    • 제42권2호
    • /
    • pp.73-83
    • /
    • 2019
  • Foot-and-Mouth Disease (FMD) is a highly contagious trans-boundary viral disease caused by FMD virus, which causes huge economic losses. FMDV infects cloven hoofed (two-toed) mammals such as cattle, sheep, goats, pigs and various wildlife species. To control the FMDV, it is necessary to understand the life cycle and the pathogenesis of FMDV in host. Especially, the protein-protein interaction between FMDV and host will help to understand the survival cycle of viruses in host cell and establish new therapeutic strategies. However, the computational approach for protein-protein interaction between FMDV and pig hosts have not been applied to studies of the onset mechanism of FMDV. In the present work, we have performed the prediction of the pig's proteins which interact with FMDV based on RNA-Seq data, protein sequence, and structure information. After identifying the virus-host interaction, we looked for meaningful pathways and anticipated changes in the host caused by infection with FMDV. A total of 78 proteins of pig were predicted as interacting with FMDV. The 156 interactions include 94 interactions predicted by sequence-based method and the 62 interactions predicted by structure-based method using domain information. The protein interaction network contained integrin as well as STYK1, VTCN1, IDO1, CDH3, SLA-DQB1, FER, and FGFR2 which were related to the up-regulation of inflammation and the down-regulation of cell adhesion and host defense systems such as macrophage and leukocytes. These results provide clues to the knowledge and mechanism of how FMDV affects the host cell.

High molecular weight water-soluble chitosan acts as an accelerator of macrophages activation by recombinant interferon ${\gamma}$ via a process involving $_L$-arginine -dependent nitric oxide production

  • Kim, Hyung-Min
    • Advances in Traditional Medicine
    • /
    • 제1권1호
    • /
    • pp.71-81
    • /
    • 2000
  • High molecular weight water-insoluble chitosan alone has been previously shown to exhibit in vitro stimulatory effect on macrophages nitric oxide (NO) production. However, high molecular weight water-soluble chitosan (WSC) had no effect on NO production by itself. When WSC was used in combination with recombinant $interferon-{\gamma}\;(Rifn-{\gamma})$, there was a marked cooperative induction of NO synthesis in a dose-dependent manner. The optimal effect of WSC on NO synthesis was shown at 24 h after treatment with $rIFN-{\gamma}$. The increased production of NO from $rIFN-{\gamma}$ plus WSC-stimulated RAW 264.7 macrophages was decreased by the treatment with $N^G$ $monomethyl-_L-arginine$. The increase in NO synthesis was reflected, as an increased amounts of inducible NO synthase (iNOS) protein. Synergy between $rIFN-{\gamma}$ and WSC was mainly dependent on WSC-induced nuclear $factor-_KB$ activation. The present results indicate that WSC may provide various activities such as anti-microbial, anti-tumoral, and anti-viral. In addition, since NO has emerged as an important intracellular and intercellular regulatory molecule having functions as diverse as vasodilation, neural communication, cell growth regulation and host defense, it is tempting to hypothesize that this WSC is involved in the local control of the various fundamental processes such as cardiagra, cardiac infarction, impotence etc.

  • PDF

돌외 에탄올 추출물의 생체방어력 증진효능 (Augmentation of Immune Responses by Oral Administration of Gynostemma pentaphyllum Ethanol Extract)

  • 임선아;최현숙;황방연;이명구;이종길
    • 생약학회지
    • /
    • 제40권1호
    • /
    • pp.35-40
    • /
    • 2009
  • The immunomodulatory activities of the ethanol extract of Gynostemma pentaphyllum, termed hereafter as GPE, were examined in immunosuppressed mice as well as in normal mice in the present study. Oral administration of GPE into mice prevented dexamethasone (DEX)-induced immunosuppression as determined by the mitogen-induced proliferation of the splenocytes and the the cytokine production (TNF-$\alpha$, IL-$1{\beta}$) in the whole blood culture. In addition, oral administration of GPE increased antitumor host defense in mice implanted with sarcoma-180 tumor cells. The immunoaugmenting activity of orally administered GPE was also confirmed in mice immunized with ovalbumin (OVA). Mice that were orally administered with GPE generated much more potent OVA-specific cytotoxic T lymphocyte (CTL) responses upon intravenous OVA injection compared to the untreated controls. These results demonstrate that oral administration of the ethanol extract of Gynostemma pentaphyllum could be useful to increase host defense in immunocompromised situations such as stress- or tumor-induced immunosuppression.

Mini-review: oomycete RXLR genes as effector-triggered immunity

  • Arif, Saima;Jang, Hyun A;Kim, Mi-Reu;Oh, Sang-Keun
    • 농업과학연구
    • /
    • 제45권4호
    • /
    • pp.561-573
    • /
    • 2018
  • Oomycetes are known to secrete a vast arsenal of effectors that modulate the host defense system as well as facilitate establishing a parasitic infection in plants. In recent years, tremendous progress has been made in the field of effectromics based on studies of oomycetes, especially the cytoplasmic family of RXLR effectors. Yet, the biology of the RXLR effector family is still poorly understood. There has been a consensus regarding the structure of the RXLR motif in the mycologist community. However, the function of the RXLR motif is still unclear. First, different models have suggested that the role of the RXLR motif is either in translocation to a target destination inside a host cell or in the cleavage of itself followed by secretion. Second, recent studies have suggested different functional models for the RXLR motif. According to a widely accepted model, the RXLR motif is directly involved in the translocation of effectors to target sites. In contrast, a new study has proposed that the RXLR motif is involved in secretion rather than translocation. Thus, this review is an attempt to summarize the recent advances made in the functional analysis of the N-terminal domain of RXLR effectors.

A Study on the AoA Based Defense Decision Making

  • Lee, Kyoung Haeng;Kwon, Yong Soo
    • 시스템엔지니어링학술지
    • /
    • 제7권1호
    • /
    • pp.1-7
    • /
    • 2011
  • This work describes a study on the Analysis of Alternatives (AoA) based defense decision making. Future battle-space is transformed into a System of Systems (SoS) concept which is accomplished missions and their functions through network based battle management systems under forming their grids of various sensors and shooters in a single theater. The acquisition process is, therefore, changing over from single system requirements to capabilities based acquisition of SoS. AoA help to justify the need for starting, stopping, or continuing an acquisition program. AoA identify potentially viable solutions and provide comparative cost, effectiveness, and risk assessments of each solution to a baseline. The decision making must consider not only cost-effectiveness, risk, and military worth, but also domestic policy, foreign policy, technological maturity of the solution, the environment, the budget, treaties, and a host of additional factors. In this point of view, this paper analyzes AoA template which are critical elements of the defense decision making. From results of this analysis of AoA template for Korean acquisition environment are presented.

Antimicrobial Peptides in Innate Immunity against Mycobacteria

  • Shin, Dong-Min;Jo, Eun-Kyeong
    • IMMUNE NETWORK
    • /
    • 제11권5호
    • /
    • pp.245-252
    • /
    • 2011
  • Antimicrobial peptides/proteins are ancient and naturally-occurring antibiotics in innate immune responses in a variety of organisms. Additionally, these peptides have been recognized as important signaling molecules in regulation of both innate and adaptive immunity. During mycobacterial infection, antimicrobial peptides including cathelicidin, defensin, and hepcidin have antimicrobial activities against mycobacteria, making them promising candidates for future drug development. Additionally, antimicrobial peptides act as immunomodulators in infectious and inflammatory conditions. Multiple crucial functions of cathelicidins in antimycobacterial immune defense have been characterized not only in terms of direct killing of mycobacteria but also as innate immune regulators, i.e., in secretion of cytokines and chemokines, and mediating autophagy activation. Defensin families are also important during mycobacterial infection and contribute to antimycobacterial defense and inhibition of mycobacterial growth both in vitro and in vivo. Hepcidin, although its role in mycobacterial infection has not yet been characterized, exerts antimycobacterial effects in activated macrophages. The present review focuses on recent efforts to elucidate the roles of host defense peptides in innate immunity to mycobacteria.

From Recognition to Defense Responses in Rice Plant

  • Jwa, Nam-Soo
    • 한국식물병리학회:학술대회논문집
    • /
    • 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
    • /
    • pp.13-13
    • /
    • 2003
  • When plants are infected by plant pathogens, rapid cell responses are initiated for further inhibition from fast invasion of pathogens. Hypersensitive response (HR) of plant is well known defense response stopping pathogenesis process through rapid cell death. However, informations on the signaling pathway from reception of pathogen by host plants to appropriate resistant responses are very limited to date. Efficient perception of infection by pathogens and well-programmed signalling mechanism for appropriate responses are important for survival of plants. Plant have developed a sophisticated network(s) of defense/stress responses, among which one of the earliest signalling pathways after perception (of stimuli) is the evolutionary conserved Rop GTPase and mitogen-activated protein kinase (MAPK) cascade.(중략)

  • PDF