• IMMUNE NETWORK
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• 제21권3호
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• pp.20.1-20.18
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• 2021

The gut is an important organ with digestive and immune regulatory function which consistently harbors microbiome ecosystem. The gut microbiome cooperates with the host to regulate the development and function of the immune, metabolic, and nervous systems. It can influence disease processes in the gut as well as extra-intestinal organs, including the brain. The gut closely connects with the central nervous system through dynamic bidirectional communication along the gut-brain axis. The connection between gut environment and brain may affect host mood and behaviors. Disruptions in microbial communities have been implicated in several neurological disorders. A link between the gut microbiota and the brain has long been described, but recent studies have started to reveal the underlying mechanism of the impact of the gut microbiota and gut barrier integrity on the brain and behavior. Here, we summarized the gut barrier environment and the 4 main gut-brain axis pathways. We focused on the important function of gut barrier on neurological diseases such as stress responses and ischemic stroke. Finally, we described the impact of representative environmental sensors generated by gut bacteria on acute neurological disease via the gut-brain axis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제39권6호
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• pp.292-296
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• 2013

Verruciform xanthoma (VX) is a rare, benign lesion that presents in the oral cavity, skin, or genital organs as a verrucous, papillomatous, or flat papule with varying colors. VX has indistinct clinical features, making histopathological examination necessary for a definitive diagnosis. Histologically, VX is characterized by parakeratosis, rete ridges with uniform depth, and an accumulation of the foam cells, which are also known as the "xanthoma cells". These foam cells test positive for antibodies, such as CD-68 and vimentin; it is thought that VX foam cells are derived from the monocyte-macrophage lineage, and that VX's pathogenic mechanism is partly related to an immune mechanism. Nevertheless, the pathogenesis of VX remains unclear. VX can be treated by surgical excision; other medical, chemical, and radiological treatments are not required postoperatively. Recurrence and malignant transformation of VX are rare. Two patients, each with a mass of unknown origin on the palatal gingiva, were presented at our clinic. Excisional biopsies of the masses were performed for a histological diagnosis after clinical and radiological examinations. Histological examination confirmed a diagnosis of VX in both cases.

• Asian-Australasian Journal of Animal Sciences
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• 제16권4호
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• pp.596-608
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• 2003

Weaning is a complex phase when the mammal suffers the action of different stressors that contribute to negatively affect the efficiency of the intestinal mucosa and of the whole local integrated system, that acts as barrier against any nocuous agent. The components of this barrier are mechanical, chemical, and bacteriological; immunological and not. The development of contact with a saprophyte microflora and the maintenance of feed intake after the interruption of motherly nutrition are essential for the maturation of an equilibrated local immune function and for a functional integrity of villi. Opportunities and limits of some dietary strategies that can contribute to reduce negative effects of weaning on health and performance are discussed. Knowledges on the possible mechanism of action of probiotics are upgraded, particularly for their supposed role in the balance between different immune functions (effectory/regulatory). Some tools to control pathogen microflora are reviewed (acids, herbs, immunoglobulin sources) and practical feeding systems are proposed.

• IMMUNE NETWORK
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• 제1권2호
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• pp.95-103
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• 2001

T cells play a central role in the initiation and regulation of the immune response to foreign antigens. Full activation of T cells requires the engagement of T cell receptor complex (TCR) and the binding of a second costimulatory receptor to its ligand expressed on antigen presenting cells (APC). Among the molecules known to provide costimulatory function, CD28 has been the most dominant and potent costimulatory molecule. However, the function of CD28 is becoming more complex due to the recent discovery of its structural homologue, CTLA-4 and ICOS. This review summarizes the biology and physiologic function of each of these receptors, and further focuses on the biochemical mechanism underlying the function of these receptors. Complete understanding of the CD28/CTLA-4/ICOS costimulatory pathway will provide the basis for developing new therapeutic approaches for immunological dieseases.

• BMB Reports
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• 제38권2호
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• pp.121-127
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• 2005

Drosophila protects itself from infection by microbial organisms by means of its pivotal defense, the so-called innate immunity system. This is its sole defense as it lacks an adaptive immunity system such as is found in mammals. The strong conservation of innate immunity systems in organisms from Drosophila to mammals, and the ease with which Drosophila can be manipulated genetically, makes this fly a good model system for investigating the mechanisms of virulence of a number of medically important pathogens. Potentially damaging endogenous and/or exogenous challenges sensed by specific receptors initiate signals via the Toll and/or Imd signaling pathways. These in turn activate the transcription factors Dorsal, Dorsal-related immune factor (Dif) and Relish, culminating in transcription of genes involved in the production of antimicrobial peptides, melanization, phagocytosis, and the cytoskeletal rearrangement required for appropriate responses. Clarifying the regulatory interactions between the various pathways involved is very important for understanding the specificity and termination mechanism of the immune response.

• BMB Reports
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• 제32권5호
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• pp.419-428
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• 1999

Tumor necrosis factor (TNF) receptor members have unique structures composed of 2-4 cysteine - rich pseudorepeats in the extracellular domain. On ligation by trimeric ligand molecules, oligomerization of three receptor molecules occurs, which in turn activates the receptor and recruits intracellular signaling molecules to the cytoplasmic tail to initiate biological events. Recently, the numbers of tumor necrosis factor receptor and ligand family members have been rapidly expanding. Functional characterization of the new members has indicated redundant roles with other known members as well as provided insights into novel functions. In particular, identification of soluble decoy receptors which have the ability to bind multiple ligands highlights a complex control mechanism of immune responses by these molecules. Studies of the new members have also revealed that the TNF receptor and ligand family members play an important role in other than the immune system.

• 대한한방소아과학회지
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• 제16권2호
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• pp.51-58
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• 2002

Crohn's disease is an indolent, chronic inflammatory bowel disease capable of involving the entire alimentary tract. The exact etiology and pathogenesis remain unknown despite a long and intensive research, but the finding of various abnormalities of the immune response in patients with Crohn's disease has led to the concepts that immune mechanism is involved in the pathogenesis of this disease. Recently, we have experienced a case of Crohn's disease. So the purpose of this study is to examine the efficacy of Oriental medicine for Crohn's disease.

• Animal cells and systems
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• 제13권1호
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• pp.1-8
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• 2009

Toll-like receptor (TLR) family proteins, type I transmembrane proteins, play a central role in human innate immune response by recognizing common structural patterns in diverse molecules from bacteria, viruses and fungi. Recently four structures of the TLR and ligand complexes have been determined by high resolution x-ray crystallographic technique. In this review we summarize reported structures of TLRs and their proposed activation mechanisms. The structures demonstrate that binding of agonistic ligands to the extracellular domains of TLRs induces homo- or heterodimerization of the receptors. Dimerization of the TLR extracellular domains brings their two C-termini into close proximity. This suggests a plausible mechanism of TLR activation: ligand induces dimerization of the extracellular domains, which enforces juxtaposition of intracellular signaling domains for recruitment of intracellular adaptor proteins for signal initiation.

• 한국균학회지
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• 제8권2호
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• pp.115-116
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• 1980

To investigate mechanism of antineoplastic activities of the protein-polysaccharide fraction of Coriolus versicolor (Fr.) Quel., the mycelium of the fungus was grown in a liquid medium and was extracted with hot water. The extract was purified and used for examining its effects upon immune response in mice. The fraction was administered at a dose of 20mg/kg/day to ICR mice for five days. After ten days the mice were immunized by sheep red blood cells. The plaque-forming cells (PFC) in their spleen were increased in the treated mice. The number of PFC in case of the protein-removed polysaccharide was lower than that of the entire protein-­polysaccharide fraction of the fungus.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2003년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.369-369
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• 2003

Hemocytes in marine bivalves play important immunological roles in discrimination, opsonization and phagocytosis of foreign materials as a defense mechanism. In this study we report the flow cytometric implications to investigate the immune parameters such as the compositional and the functional characteristics of hemocytes isolated from the Manila clams, Ruditapes philippinarum. Heterogeneity of the hemocytic cell population was determined by the forward scatter (FSC) and side scatter (SSC) cytometric profile which showed three populations: granulocytes, hyalinocytes and small agranular cells. In addition, phagocytosis rate was measured after adding fluorescent-labeled particles. The data were initially analysed for two-parameters: FSC and SSC, then the fluorescent (FL 1) frequency distribution histogram of the hemocyte population was subsequently obtained.