• 제목/요약/키워드: Host-pathogen

검색결과 420건 처리시간 0.022초

Host Innate Immunity against Hepatitis E Virus and Viral Evasion Mechanisms

  • Kang, Sangmin;Myoung, Jinjong
    • Journal of Microbiology and Biotechnology
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    • 제27권10호
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    • pp.1727-1735
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    • 2017
  • Hepatitis E virus (HEV) infections cause epidemic or sporadic acute hepatitis, which are mostly self-limiting. However, viral infection in immunocompromised patients and pregnant women may result in serious consequences, such as chronic hepatitis and liver damage, mortality of the latter of which reaches up to 20-30%. Type I interferon (IFN)-induced antiviral immunity is known to be the first-line defense against virus infection. Upon HEV infection in the cell, the virus genome is recognized by pathogen recognition receptors, leading to rapid activation of intracellular signaling cascades. Expression of type I IFN triggers induction of a barrage of IFN-stimulated genes, helping the cells cope with viral infection. Interestingly, some of the HEV-encoded genes seem to be involved in disrupting signaling cascades for antiviral immune responses, and thus crippling cytokine/chemokine production. Antagonistic mechanisms of type I IFN responses by HEV have only recently begun to emerge, and in this review, we summarize known HEV evasion strategies and compare them with those of other hepatitis viruses.

Possible Association of Indole-3-Acetic Acid Production by Xanthomonas axonopodis pv. glycines with Development of Pustule Disease in Soybean

  • Kim, Hong-Suk;Park, Hyoung-Joon;Heu, Sunggi;Jung, Jin
    • Journal of Applied Biological Chemistry
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    • 제44권4호
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    • pp.173-176
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    • 2001
  • This report concerns the role of indole-3-acetic acid (IAA) in bacterial pustule disease of soybean. Pustule production in soybean leaves caused by Xanthomonas axonopodis pv. glycines was accompanied by a drastic increase in IAA content of host tissues. The phytopathogenic bacterium synthesized IAA in a tryptophan concentration-dependent manner when grown in a defined minimal medium. In complex media, however, the pathogen showed no response to tryptophan feeding, implying that the bacterial biosynthetic machinery of IAA is strictly regulated by nutrient availability of its growth environments. The results may suggest that IAA of bacterial origin and tryptophan of plant origin be involved in the process of pustule symptom development in soybean.

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Biological Infectious Watermarking Model for Video Copyright Protection

  • Jang, Bong-Joo;Lee, Suk-Hwan;Lim, SangHun;Kwon, Ki-Ryong
    • Journal of Information Processing Systems
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    • 제11권2호
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    • pp.280-294
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    • 2015
  • This paper presents the infectious watermarking model (IWM) for the protection of video contents that are based on biological virus modeling by the infectious route and procedure. Our infectious watermarking is designed as a new paradigm protection for video contents, regarding the hidden watermark for video protection as an infectious virus, video content as host, and codec as contagion medium. We used pathogen, mutant, and contagion as the infectious watermark and defined the techniques of infectious watermark generation and authentication, kernel-based infectious watermarking, and content-based infectious watermarking. We experimented with our watermarking model by using existing watermarking methods as kernel-based infectious watermarking and content-based infectious watermarking medium, and verified the practical applications of our model based on these experiments.

From Recognition to Defense Responses in Rice Plant

  • Jwa, Nam-Soo
    • 한국식물병리학회:학술대회논문집
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    • 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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    • pp.13-13
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    • 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)

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Fluorescent siderophore 생산균주, TS3-7에 의한 풋마름병 발병 억제 (Suppression of Bacterial Wilt with Fuorescent Pseudomonads, TS3-7 strain)

  • 김지태;조홍범;김신덕
    • Applied Biological Chemistry
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    • 제48권3호
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    • pp.296-300
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    • 2005
  • Among the root colonizing and plant growth promoting bacteria isolated from the bacterial wilt suppressive soil, five strains were detected to produce siderophores by CAS agar assay. The most effective isolate, TS3-7 strain induced significant suppression of bacterial wilt disease in tomato and pepper plants. Seed treatment followed by soil drench application with this strain resulted in over 80% reduction of bacterial wilt disease compared with the control. Significant disease suppression by TS3-7 strain was related to the production of siderophore. Besides iron competition, induction of resistance of the host plant with siderophore was suggested to be another mode of action that suppress bacterial wilt, based on the lack of direct antibiosis against pathogen in vitro. According to Bergey's Manual of Systemic Bacteriology and 16S rDNA sequence data, TS3-7 stain was identified as Pseudomonas sp. TS3-7.

Soft Rot of Rhizopus oryzae as a Postharvest Pathogen of Banana Fruit in Korea

  • Kwon, Jin-Hyeuk;Ryu, Jae-San;Chi, Tran Thi Phuong;Shen, Shun-Shan;Choi, Ok-Hee
    • Mycobiology
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    • 제40권3호
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    • pp.214-216
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    • 2012
  • Soft rot on banana fruit caused by Rhizopus oryzae was identified for the first time in Korea. Colonies were white to light brown and formed numerous sporangiospores. Optimum temperature for mycelial growth was $30^{\circ}C$. Sporangia were globose and $30{\sim}200{\mu}m$. Sporangiophores were usually straight, $8{\sim}20{\mu}m$, and rhizoids usually in groups of 3~5. Columella were globose to sub-globose and $90{\sim}110{\mu}m$. Sporangiospores were sub-globose or oval and $4{\sim}10{\mu}m$. Based on its mycological characteristics, molecular analysis, and pathogenicity to host plants, this fungus was identified as Rhizopus oryzae Went & Prisen Geerligs. This is the first report of soft rot on banana caused by Rhizopus oryzae in Korea.

Restriction-modification system and genetic variability of Xanthomonas oryzae pv. oryzae

  • Choi, Seong-Ho
    • 한국식물병리학회:학술대회논문집
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    • 한국식물병리학회 1995년도 Proceedings of special lectures on Molecular Biological Approaches to Plant Disease National Agricultural Science and Technology Institute Suwon, Korea
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    • pp.21-25
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    • 1995
  • ;Bacterial blight caused by Xanthomonas oryzae pv. Olyzae is one of the most important diseases of rice. Host resistance, which relies on single, dominant resistance genes, is the only reliable method to control the disease at present. Pathogenic variation of the bacteria has been shown to follow the deployment of resistance genes in commercial cultivars. Information on the factors and the mechanisms for genetic variation of this pathogen is limited. Further, we have no clear evidence of whether population variability is due to sexual recombination or to variation introduced by mutations or intragenic recombination in a clonally maintained population.(omitted)itted)

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포장위생 관리가 콩 미이라병의 발생에 미치는 영향 (Effect of Field Sanitation on the Pod and Stem Blight Caused by Phomopsis spp. in Soybean)

  • 오정행
    • 한국식물병리학회지
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    • 제14권5호
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    • pp.526-530
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    • 1998
  • The effect of field sanitation using ecological characters of the pathogen was investigated for controlling Phomopsis seed decay in soybean. Field sanitation which was eliminated the inoculum by removing host debris, abscised petioles and cotyledones out of field, reduced remarkably infection percentage of pods and seeds by Phomopsis spp. as compared to the inoculated field. Neverthless, seed infection was 28.7% in the sanitized field. The fields sanitized by benlate application around the soybean plants also decreased seed infection with Phomopsis spp. Total seed infection including that with miscellaneous pathogens occurred as much as 75∼79% to the no application and their control values were 34∼42% over the routine application schedule. Even though it was not satisfactory, field sanitation seemed to be effective in controlling Phomopsis seed decay when infection pressure was low level. Diaporthe phseolorum va. sojae, D. phaseolorum var. caulivora and Phomopsis longicolla were mostly identified from soybean seeds and Colletotrichum truncatum, Cercospora kikuchiana were also isolated in sequence. Field sanitation did not significantly increase in soybean yield over the no application, while routine application schedule did in field.

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흰생쥐에서 분리(分離)된 대장요충(大腸蟯蟲)과 맹장요충(盲腸蟯蟲)에 관(關)한 연구(硏究) (Prevalence of Oxyurid Pinworms, Aspiculuris tetraptera, Syphacia muris and S. obvelata in the Laboratory Albino Mice, Mus musculus alba)

  • 강영배;김상희;김동성
    • 대한수의학회지
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    • 제27권1호
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    • pp.85-91
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    • 1987
  • For the development of the specific pathogen free (SPF) or germ free laboratory animals, a parasitological survey was carried out and numerous pinworms were collected from the large intestines and caeca of the host animal Mus musculus alba. The pinworms collected from the laboratory albino mice were identified as Aspiculuris tetraptera, Syphacia muris and S. obvelata and classified into the Family Oxyuridae, Superfamily Oxyuroidea, Order Ascaridida. The overall infection rate of the pinworms was revealed as high as 64.8%(A. tetraptera 31.0%; S. muris 32.4% and S. obvelata 22.5%) consisting of the single species infection 47.9%, the double species infection 12.7% and the triple species infection 4.2%.

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흰생쥐에서 분리(分離)된 쥐 모식응애 (Myocoptes musculinus)에 관(關)한 형태(形態) 및 생태관찰(生態觀察) (Morphological and Ecological Observations on Myocoptes musculinus Koch 1844(Sarcoptiformes; Listrophoridae) Collected from Mus musculus alba)

  • 강영배
    • 대한수의학회지
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    • 제27권1호
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    • pp.77-83
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    • 1987
  • For the development of the specific pathogen free (SPF) or germ free laboratory animals, a parasitological approach was applied to the preliminarily selected laboratory albino mice (Mus musculus alba) in order to observe the ectoparasites on the hair of the host animal. The mites collected from the laboratory albino mice were identified as Myocoptes musculinus and classified into the Family Listrophoridae, Suborder Sarcoptiformes, Order Acarina. The overall infection rate of the mites was revealed as high as 73.2% (52 out of 71 heads) and the development process from the eggs to larvae was observed for the understanding of the basic ecological properties.

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