• 제목/요약/키워드: Immune mechanism

검색결과 657건 처리시간 0.027초

Practical Swarm Optimization based Fault-Tolerance Algorithm for the Internet of Things

  • Luo, Shiliang;Cheng, Lianglun;Ren, Bin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권3호
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    • pp.735-748
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    • 2014
  • The fault-tolerance routing problem is one of the most important issues in the application of the Internet of Things, and has been attracting growing research interests. In order to maintain the communication paths from source sensors to the macronodes, we present a hybrid routing scheme and model, in which alternate paths are created once the previous routing is broken. Then, we propose an improved efficient and intelligent fault-tolerance algorithm (IEIFTA) to provide the fast routing recovery and reconstruct the network topology for path failure in the Internet of Things. In the IEIFTA, mutation direction of the particle is determined by multi-swarm evolution equation, and its diversity is improved by the immune mechanism, which can improve the ability of global search and improve the converging rate of the algorithm. The simulation results indicate that the IEIFTA-based fault-tolerance algorithm outperforms the EARQ algorithm and the SPSOA algorithm due to its ability of fast routing recovery mechanism and prolonging the lifetime of the Internet of Things.

Autophagy in neutrophils

  • Shrestha, Sanjeeb;Lee, Jae Man;Hong, Chang-Won
    • The Korean Journal of Physiology and Pharmacology
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    • 제24권1호
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    • pp.1-10
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    • 2020
  • Autophagy is a highly conserved intracellular degradation and energy-recycling mechanism that contributes to the maintenance of cellular homeostasis. Extensive researches over the past decades have defined the role of autophagy innate immune cells. In this review, we describe the current state of knowledge regarding the role of autophagy in neutrophil biology and a picture of molecular mechanism underlying autophagy in neutrophils. Neutrophils are professional phagocytes that comprise the first line of defense against pathogen. Autophagy machineries are highly conserved in neutrophils. Autophagy is not only involved in generalized function of neutrophils such as differentiation in bone marrow but also plays crucial role effector functions of neutrophils such as granule formation, degranulation, neutrophil extracellular traps release, cytokine production, bactericidal activity and controlling inflammation. This review outlines the current understanding of autophagy in neutrophils and provides insight towards identification of novel therapeutics targeting autophagy in neutrophils.

Antimicrobial Peptides (AMPs) with Dual Mechanisms: Membrane Disruption and Apoptosis

  • Lee, Juneyoung;Lee, Dong Gun
    • Journal of Microbiology and Biotechnology
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    • 제25권6호
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    • pp.759-764
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    • 2015
  • Antimicrobial peptides (AMPs) are one of the critical components in host innate immune responses to imbalanced and invading microbial pathogens. Although the antimicrobial activity and mechanism of action have been thoroughly investigated for decades, the exact biological properties of AMPs are still elusive. Most AMPs generally exert the antimicrobial effect by targeting the microbial membrane, such as barrel stave, toroidal, and carpet mechanisms. Thus, the mode of action in model membranes and the discrimination of AMPs to discrepant lipid compositions between mammalian cells and microbial pathogens (cell selectivity) have been studied intensively. However, the latest reports suggest that not only AMPs recently isolated but also well-known membrane-disruptive AMPs play a role in intracellular killing, such as apoptosis induction. In this mini-review, we will review some representative AMPs and their antimicrobial mechanisms and provide new insights into the dual mechanism of AMPs.

Practical Swarm Optimization based Fault-Tolerance Algorithm for the Internet of Things

  • Luo, Shiliang;Cheng, Lianglun;Ren, Bin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권4호
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    • pp.1178-1191
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    • 2014
  • The fault-tolerance routing problem is one of the most important issues in the application of the Internet of Things, and has been attracting growing research interests. In order to maintain the communication paths from source sensors to the macronodes, we present a hybrid routing scheme and model, in which alternate paths are created once the previous routing is broken. Then, we propose an improved efficient and intelligent fault-tolerance algorithm (IEIFTA) to provide the fast routing recovery and reconstruct the network topology for path failure in the Internet of Things. In the IEIFTA, mutation direction of the particle is determined by multi-swarm evolution equation, and its diversity is improved by the immune mechanism, which can improve the ability of global search and improve the converging rate of the algorithm. The simulation results indicate that the IEIFTA-based fault-tolerance algorithm outperforms the EARQ algorithm and the SPSOA algorithm due to its ability of fast routing recovery mechanism and prolonging the lifetime of the Internet of Things.

A novel role of Hippo-Yap/TAZ signaling pathway in lymphatic vascular development

  • Cha, Boksik;Moon, Sungjin;Kim, Wantae
    • BMB Reports
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    • 제54권6호
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    • pp.285-294
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    • 2021
  • The lymphatic vasculature plays important role in regulating fluid homeostasis, intestinal lipid absorption, and immune surveillance in humans. Malfunction of lymphatic vasculature leads to several human diseases. Understanding the fundamental mechanism in lymphatic vascular development not only expand our knowledge, but also provide a new therapeutic insight. Recently, Hippo-YAP/TAZ signaling pathway, a key mechanism of organ size and tissue homeostasis, has emerged as a critical player that regulate lymphatic specification, sprouting, and maturation. In this review, we discuss the mechanistic regulation and pathophysiological significant of Hippo pathway in lymphatic vascular development.

EBM 기반 구축을 위한 팔물탕 문헌 연구 분석 (Analysis of Studies on Palmul-tang for Establishment of Evidence Based Medicine)

  • 마충제;이남헌;마진열;하혜경;유영법;신현규
    • 대한한의학방제학회지
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    • 제15권2호
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    • pp.35-45
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    • 2007
  • Objective : The purpose of this report was to provide the information activity and safety of Palmul-tang by analyzing domestic/international papers and theses about Palmul-tang, Methods: Domestic/international papers and theses related to Palmul-tang were reviewed and analyzed, These papers were then classified by year, experimental method and subject, Results: The following results were obtained in this study. 1. The study of Palmul-tang started from 1985 and was continuously increased. The study was mainly forcused on experimental model rather than clinical study. 2. As these studies were classified by subject, papers related to immune intensification were most abundant by 20 papers, Besides there were several papers related to cardiovascular activity, reproductive activity, anti-apoptotic activity and cerebral hemodynamics. 3. Among the papers related to immune intensification. the studies on recovery of fatigue were mostabundant by 10 papers and the studies of on immune cell and cytokine express were six. In addition to. several studies were associated with anti-cancer activity and anti-allergic activity. Recovery of fatigue was determined by measurement of fatigue markers in a living body such as lactate. CPK, pyruvate and triglyceride and assessment of exercise capability of animals such as swimming test. slopped plate test. Rota-rod test, and activity cage test after Palmul-tang treatment. 4. According to experimental data. it is supported that Palmul-tang has been used as Qi and Blood intensifier with immune intensification and recovery of fatigue. 5. The paper related to safety of Palmul-tang was only one paper which is studied on acute toxicity of Palmul-tang with experiment with ICR mouse. There was no study on evaluating safety by observing liver and kidney functions after Palmul-tang treatment Conclusion: Palmul-tang is being used in various ways associating with immune intensification. cardiovascular activity and reproductive activity. However. studies on efficacy and mechanism of Palmul-tang should be conducted at the molecular biology level and studies on safety of Palmul-tang need to be completed at the clinical level.

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염증성 장질환과 사이토카인 (Inflammatory Bowel Disease and Cytokine)

  • 최은영;조광근;최인순
    • 생명과학회지
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    • 제23권3호
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    • pp.448-461
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    • 2013
  • 크론병과 궤양성 대장염으로 잘 알려져 있는 염증성 장질환은 재발과 호전을 반복하는 만성적인 염증 및 이에 따른 합병증을 특징으로 하는 원인 불명의 질환이다. 염증성 장질환의 발생 원인은 아직 명확히 알려져 있지 않지만 흡연이나 식이와 같은 환경적 요인, 장내 세균총과 같은 미생물학적 요인, 면역 매개에 의한 조직 손상과 같은 면역학적 요인 그리고 유전학적 요인 등이 복합적으로 발생기전에 관여 할 것이라고 추정한다. 특히 사이토카인과 같은 염증매개물질에 의해 세포매개염증반응의 일련의 과정이 유발 혹은 증폭되거나, 면역 조절 기능의 면화로 장 점막의 국소적 조직 손상을 유발하게 되며 면역 및 염증 반응이 적절하게 감소되지 않고 지속되어 만성 염증에 이르게 된다. 최근 이러한 염증반응에 중요한 역할을 담당하는 사이토카인 유전자에 관심이 몰리고 있다. 사이토카인은 활성화된 면역세포에서 주로 생성되는 당단백으로서 분자량이 8~10 kD 정도이며, 면역 반응시 T세포, B세포, 대식세포 등의 면역세포 상호간에 활성화, 증식 및 분화 등에 관계하여 국소적 조직 손상 및 염증반응을 일으킨다. 반면에 장의 구조와 기능에 있어 중요한 기질인 식이 섬유소에서 유래되는 Butyrate는 친염증성 사이토카인을 감소시키고 항염증성 사이토카인을 증가시킴으로써 장관 면역계에 대한 조절기능을 보이고 있다. 따라서 본 총설에서는 Butyrate의 항염증 효과에 대한 분자적 기작을 면역세포에서 Butyrate가 가지는 사이토카인 조절 능력을 통해 이해하고 Butyrate가 염증성 장질환에 대해 새로운 치료 전략을 제시 해 줄 것으로 기대한다.

게르마늄 강화효모의 마우스에서의 암세포 억제 및 대식세포, NK 세포, B 세포의 활성화에 관한 연구 (Germanium-Fortified Yeast Activates Macrophage, NK Cells and B Cells and Inhibits Tumor Progression in Mice.)

  • 백대헌;정진욱;손창욱;강종구
    • 한국미생물·생명공학회지
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    • 제35권2호
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    • pp.118-127
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    • 2007
  • 본 연구는 마우스를 대상으로 유기게르마늄 강화효모 경구투여에 의한 면역조절작용 효과를 확인하고자 하였다. 마우스를 대상으로 9일간 경구투여한 결과 대조군인 게르마늄 비강화 효모 투여군에 비해 복강대식세포, B세포, NK 세포의 활성이 현저히 증가한 것으로 확인되었으며, 최종 실험결과 대식세포는 게르마늄 강화효모 투여 후 식세포활성, 주화성, 부착성, rosette 형성능 현저히 증가하였다. Superoxide $anion(O_2^-)$ 생성능은 대조군에 비해 유기게르마늄 강화군 투여군에서 3배 활성이 증가하였으며, NO 생성능과 $TNF-{\alpha}$ 생성능도 농도의존적으로 증가하였다. B-세포 활성화에 의한 cytolytic activity 증가에 의한 PFC형성능도 게르마늄 비강화 효모에 비해 현저히 증가하였으며 상업화 유기게르마늄으로 알려지고 있는 Ge-132에 비해 2배 이상 높은 활성이 확인되었다. Cytotoxic acivity에 의한 항 종양활성에서는 양성대조군인 Doxorubicin 투여군에서와 유사한 저해활성을 나타내었으며 고용량 유기게르마늄 효모(2,400 mg/kg) 투여시 60%의 종양활성 억제효과가 확인되었다. 이러한 결과를 종합해 볼 때 유기게르마늄 강화효모가 실험동물 뿐만 아니라 인체의 유용한 면역조절제로서의 이용성이 기대된다.

가려움증의 기전에 대한 최신 논의 고찰 - 최근의 연구 동향과 위장관계와의 연관성 (A Review of the Latest Discussions on the Mechanism of Itching - A Study on Recent Research Trend and the Relationship between Gastrointestinal Tract and Itching)

  • 김준동;한창이;서광일;김규석;김윤범
    • 한방안이비인후피부과학회지
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    • 제34권3호
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    • pp.55-69
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    • 2021
  • Objectives : The purpose of this study is to review the latest discussions on the mechanism of Itching. Methods : Articles that reviewed the mechanism of itching were searched from Pubmed (January 2016 to June 2021). In addition, review articles discussing the gastrointestinal tract and the mechanisms of pruritus were searched seperately. Results : The articles are classified into three categories. These categories are the classification according to the passage of time (acute, chronic), the immune factors involved (inflammatory, non-inflammatory), and the neurophysiological mechanism (pruritoceptive itching, neuropathic itching, neurogenic itching, psychogenic itching). In each category, the articles over the past five years are summarized and reviewed. Also, how the status of the gastrointestinal tract is reflected in itching was discussed in terms of leaky gut syndrome, neuro/gastrointestinal peptides, and gut microbiota. Conclusions : This review introduces the recently discussed mechanism of itching, and in particular, examines how the gastrointestinal tract is related to skin itching. Based on these considerations, it is expected that more diverse therapeutic approaches can be explored in the future.

Enhanced Immune Cell Functions and Cytokine Production after in vitro Stimulation with Arabinoxylans Fraction from Rice Bran

  • Choi, Eun-Mi;Kim, Ah-Jin;Hwang, Jae-Kwan
    • Food Science and Biotechnology
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    • 제14권4호
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    • pp.479-486
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    • 2005
  • Arabinoxylan, a complex polysaccharide in cereal cell walls, has recently received research attention as a biological response modifier. The immunomodulating effect of arabinoxylans from rice bran (AXrb) was studied using a combined process of extrusion and commercial hemicellulase treatment in order to elucidate the augmentation mechanism of cell-mediated immunity in vitro. The cytotoxicity of mouse spleen lymphocytes against YAC-1 tumor cells was significantly enhanced by treatment with AXrb at $10-100\;{\mu}g/mL$. In an attempt to investigate the mechanism by which AXrb enhance NK cytotoxicity, we examined the effect of AXrb on cytokine production by spleen lymphocytes. Culture supernatants of the cells incubated with AXrb were collected and analyzed for IL-2 and IFN-${\gamma}$ synthesis by ELISA. IL-2 and IFN-${\gamma}$ production were increased significantly. These results suggest that AXrb may induce Th1 immune responses. Macrophages play an important role in host defenses against tumors by killing them and producing secretory products, which protect against bacterial, viral infection and malignant cell growth. AXrb were examined for their ability to induce secretory and cellular responses in murine peritoneal macrophages. When macrophages were treated with various concentrations ($10-100\;{\mu}g/mL$) of AXrb, AXrb induced tumoricidal activity, as well as increasing phagocytosis and the production of NO, $H_2O_2$, TNF-${\alpha}$, IL-$1{\beta}$, and IL-6. These results indicate that reactive oxygen species, reactive nitrogen species, and inflammatory cytokines are likely to be the major mediators of tumoricidal activity in AXrb-treated macrophages. Therefore, AXrb may be useful in cancer immunotherapy and it is anticipated that AXrb obtained using extrusion and subsequent enzyme treatment can be used as an ingredient in nutraceuticals and cereal-based functional food.