• 제목/요약/키워드: Host University

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Host-Pathogen Interactions Operative during Mycobacteroides abscessus Infection

  • Eun-Jin Park;Prashanta Silwal;Eun-Kyeong Jo
    • IMMUNE NETWORK
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    • 제21권6호
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    • pp.40.1-40.20
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    • 2021
  • Mycobacteroides abscessus (previously Mycobacterium abscessus; Mabc), one of rapidly growing nontuberculous mycobacteria (NTM), is an important pathogen of NTM pulmonary diseases (NTM-PDs) in both immunocompetent and immunocompromised individuals. Mabc infection is chronic and often challenging to treat due to drug resistance, motivating the development of new therapeutics. Despite this, there is a lack of understanding of the relationship between Mabc and the immune system. This review highlights recent progress in the molecular architecture of Mabc and host interactions. We discuss several microbial components that take advantage of host immune defenses, host defense pathways that can overcome Mabc pathogenesis, and how host-pathogen interactions determine the outcomes of Mabc infection. Understanding the molecular mechanisms underlying host-pathogen interactions during Mabc infection will enable the identification of biomarkers and/or drugs to control immune pathogenesis and protect against NTM infection.

기생충 감염에 의한 안질환과 예방 (Ophthalmic diseases caused by parasitic infections and its prevention)

  • 주경복;노병의
    • 한국안광학회지
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    • 제7권2호
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    • pp.223-228
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    • 2002
  • 기생충의 감염에 의하여 기생충증(parasitosis)이 유발하게되며 특히 안질환을 유발할 수 있는 기생충에는 원충류(Protozoa), 선충류(Nematodes), 조충류(Cestodes) 등이 있으며 이들 기생충들은 기생충과 매개체(Vector), 기생충과 숙주(Host), 숙주(Host)와 숙주(Host)의 연결고리가 있으며 이들의 관계가 오염이 되었거나 환경이 불량하여 숙주(Host)인 사람에게 기생하게되면 기생충의 독성, 숙주(Host)의 저항성 등에 따라 조직의 파괴나 염증, 알레르기 반응 등을 일으켜 질환을 일으키며 심하면 실명까지 유발케 한다. 이를 예방하려면 깨끗한 환경과 청결을 생활하여야 한다.

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Early-type host galaxies of Type II and Ib supernovae

  • 서혜원;윤성철;정현진;이석영
    • 천문학회보
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    • 제36권1호
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    • pp.57.2-57.2
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    • 2011
  • Recent studies find that some early-type galaxies host Type II or Ibc supernovae (SNe II, Ibc). This may imply recent star formation activities in these SNe host galaxies, but a massive star origin of the SNe Ib so far observed in early-type galaxies has been questioned because of their intrinsic faintness and unusually strong Ca lines shown in the nebular phase. To address the issue, we investigate the properties of early-type SNe host galaxies using the data with Galaxy Evolution Explorer (GALEX) ultraviolet photometry and the Sloan Digital Sky Survey optical data. Our sample includes eight SNe II and one peculiar SN Ib (SN 2000ds) host galaxies as well as 32 SN Ia host galaxies. The host galaxy of SN 2005cz, another peculiar SN Ib, is also analyzed using the GALEX data and the NASA/IPAC Extragalactic Database optical data. We find that the NUV?optical colors of SN II/Ib host galaxies are systematically bluer than those of SN Ia host galaxies, and some SN II/Ib host galaxies with NUV - r colors markedly bluer than the others exhibit strong radio emission. We perform a stellar population synthesis analysis and find a clear signature of recent star formation activities in most of the SN II/Ib host galaxies. Our results generally support the association of the SNe II/Ib hosted in early-type galaxies with core collapse of massive stars. We briefly discuss implications for the progenitors of the peculiar SNe Ib 2000ds and 2005cz.

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골프장 식생과 주둥무늬차색풍뎅이 (Adoretus tenuimaculatus Waterhouse)가해 기주식물의 지역적 차이 (Vegetation of Golf Courses and Local Difference of Feeding Host Plant to Adoretus tenuimaculatus Waterhouse)

  • 이동운;추호렬;정재민;이상명;허진;성영탁
    • 아시안잔디학회지
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    • 제12권1호
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    • pp.1-16
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    • 1998
  • Vegetation of golf courses and local difference of feeding host plants of brown chafer, Adoretus tenuimaculatus Waterhouse(Coleoptera: Scarabaeidae) were investigated in golf courses. Yongwon country club in Chinhae and Tongdo country club in Yangsan Gyeongnarn, Dongrae Benest golf club in Kumjeunggu Pusan and Daegu country club in Gyeongsan Gyeongbuk province from 1995 to 1997. Vegetation and species of feeding host plant were different depending on observed place. Damaged rate of host plants were concerned with ornamental trees and natural growing host plants, and Oenothera odorata, Achyranthes japonica, Aralia elata, Viburnum awabuki, Chenapadium album var. cent rorubrum, Cornus officinalis, and Rhododendron mucronulatum were newly recorded as host plant of A. tenuimaculatus in this study. Thus, host plants of A. tenuimaculatus were 193 kinds in 48 families. Key words: Brown chafer, Adoretus tenuimaculatus, host plant, vegetation, insect-plant interaction, biological control, golf courses.

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Respiratory Syncytial Virus (RSV) Modulation at the Virus-Host Interface Affects Immune Outcome and Disease Pathogenesis

  • Tripp, Ralph A.
    • IMMUNE NETWORK
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    • 제13권5호
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    • pp.163-167
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    • 2013
  • The dynamics of the virus-host interface in the response to respiratory virus infection is not well-understood; however, it is at this juncture that host immunity to infection evolves. Respiratory viruses have been shown to modulate the host response to gain a replication advantage through a variety of mechanisms. Viruses are parasites and must co-opt host genes for replication, and must interface with host cellular machinery to achieve an optimal balance between viral and cellular gene expression. Host cells have numerous strategies to resist infection, replication and virus spread, and only recently are we beginning to understand the network and pathways affected. The following is a short review article covering some of the studies associated with the Tripp laboratory that have addressed how respiratory syncytial virus (RSV) operates at the virus-host interface to affects immune outcome and disease pathogenesis.

Short-Term Viral Evolution in Response to Passaging I. Consequences for Population Size

  • Park, Gyung-Soon;Steven E. Kelley;Hing, Jung-Lim
    • 한국생태학회:학술대회논문집
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    • 한국생태학회 2002년도 VIII 세계생태학대회
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    • pp.83-91
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    • 2002
  • The Red Queen hypothesis for the advantage of sex predicts that pathogens will evolve by increasing fitness with frequent encounters with specific host genotypes. In this study, BMV population size, measured as an indicator of fitness, was investigated during repeated passages through the same, or different host genotypes of the crop host, Hordeum vulgare (barley). Overall, mean BMV concentration within individual hosts was significantly higher in genetically homogeneous compared to heterogeneous host passage lines. In addition, BMV populations, passaged through a specific host variety, showed higher growth in that host variety compared to BMV passaged through varying varieties. These results supports the Red Queen hypothesis. However, the decrease in viral populations during passages contradicts the Red Queen. Nevertheless, the results found here show that even under simplified conditions, pathogens do not evolve in simple, predictable ways. Constraints on pathogen evolution may lead to counterintuitive results.

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Short-Term Viral Evolution in Response to Passaging I. Consequences for Population Size

  • Park, Gyung-Soon;Kelley, Steven E.;Hong, Jung-Lim
    • The Korean Journal of Ecology
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    • 제25권4호
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    • pp.217-225
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    • 2002
  • The Red Queen hypothesis for the advantage of sex predicts that pathogens will evolve by increasing fitness with frequent encounters with specific host genotypes. In this study, BMV population size, measured as an indicator of fitness, was investigated during repeated passages through the same, or different host genotypes of the crop host, Hordeum vulgare (barley). Overall, mean BMV concentration within individual hosts was significantly higher in genetically homogeneous compared to heterogeneous host passage lines. In addition, BMV populations, passaged through a specific host variety, showed higher growth in that host variety compared to BMV passaged through varying varieties. These results supports the Red Queen hypothesis. However, the decrease in viral populations during passages contradicts the Red Queen. Nevertheless, the results found here show that even under simplified conditions, pathogens do not evolve in simple, predictable ways. Constraints on pathogen evolution may lead to counterintuitive results.

Host Plant Management Techniques for the Cultivation of Viscum album var. coloratum (Kom.) Ohwi

  • Lee, Bo Duck;Seo, Hyeong Min;Park, Cheol Ho
    • 한국자원식물학회지
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    • 제29권6호
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    • pp.650-657
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    • 2016
  • Research has found that the management of the host plant is essential to mistletoe cultivation. A Trunk injection test on the host plant that contained a mixture of indole-3-butryc acid (IBA) and liquid fertilizer was conducted with respect to the improvement of the one year survival rate of mistletoe. As a result, the trunk injection experiments showed the effect of the IBA and liquid fertilizer mixture in all treatments. This mixture was effective to increase the survival rate of mistletoe by 20% with the IBA at 100 mg/L and Hyponex at 100 mg/L. The examination proved that the host plant fertilizer effect was the most effective treatment for organic fertilizer with 60% added NPK (4-2-1). Its effects were higher compared to the control at the length and diameter of one-years-old branches in the host plant, even when the parasitic mistletoe improved its growth in length, diameter, and number of branches. Comparing the control and host plant fertilizer, the latter was the most effective way to process 20 kg per a treatment effect in the experimental site and to process at any time after the inoculation. This treatment is effective to improve the growth of mistletoe by watering the host plant three times per week. Therefore, the management of the host plant is an essential element in the successful cultivation of mistletoe, not only to supply fertilizer and plant hormones to the host plant in the initial inoculation time but also to provide organic fertilizer and irrigation for the host plant.

Isolation, Physiological Characterization of Bacteriophages from Enhanced Biological Phosphorus Removal Activated Sludge and Their Putative Role

  • Lee, Sang-Hyon;Satoh, Hiroyasu;Katayama, Hiroyuki;Mino, Takashi
    • Journal of Microbiology and Biotechnology
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    • 제14권4호
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    • pp.730-736
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    • 2004
  • This study aims at characterizing the bacteriophages isolated from activated sludge performing enhanced biological phosphorous removal (EBPR) to understand the interactions between the phage-host system and bacterial community. Sixteen bacterial isolates (E1-E16) were isolated as host bacterial strains from EBPR activated sludge for phage isolation. Forty bacteriophages based on their plaque sizes (2 plaques on E4, 4 on E8, 11 on E10, 5 on E14, 18 on E16) were obtained from filtered supernatant of the EBPR activated sludge. Each bacteriophage did not make any plaque on bacterial strains tested in this study except on its own host bacterial strain, respectively, indicating that the bacteriophages are with narrow host specificity. However, fourteen of the forty bacteriophages obtained in this study lost their virulent ability even on their own host bacteria. All of the lytic phages showed similar one-step growth patterns and had long latent period (about 9 hours) to reproduce their phage particles in their host bacterial cells. On the other hand, their probable burst sizes (6 to 48 per host cell) were large enough to actively lyse their host bacterial cells. Therefore, it could be implied that bacteriophages are also important members of the microbial community in EBPR activated sludge, and lytic phages directly decrease the population size of their host bacterial groups in EBPR activated sludge by lysis.

CTLA-4-Tg/CD-28-KO Mice Exhibit Reduced T Cell Proliferation in vivo Compared to CD-28-KO Mice in a Graft-versus-host Disease Model

  • Yoo, Jong-Sun;Lee, Yun-Jung;Yoon, Joo-Won;Hyung, Kyeong-Eun;Hwang, Kwang-Woo
    • The Korean Journal of Physiology and Pharmacology
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    • 제16권5호
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    • pp.349-353
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    • 2012
  • Activated T cells express inhibitory receptors such as CTLA-4 that can downregulate immune responses. Blockade of or genetic deficiency in CTLA-4 can result in autoimmunity. Therefore, strategies to increase the inhibitory function of CTLA-4 may be attractive in settings of undesirable T cell responses such as autoimmunity or transplant rejection. We have tested the hypothesis that transgenic constitutive expression of CTLA-4 can further attenuate immune responses when compared with normal inducible expression. Our results indicate that transgenic expression of CTLA-4 in mouse T cells (CTLA-4-Tg T cells) results in reduced cell cycle progression and increased apoptosis of TCR-stimulated T cells. CTLA-4-Tg T cells display reduced T cell proliferation in an in vivo model of graft versus host disease (GVHD). These results further our understanding of how CTLA-4 can be manipulated to inhibit immune responses and may help development of new therapeutic strategies for clinical settings of autoimmunity and transplantation.