• The Korean Journal of Physiology and Pharmacology
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• 제26권3호
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• pp.175-182
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• 2022

Translocation of azurophil granules is pivotal for bactericidal activity of neutrophils, the first-line defense cells against pathogens. Previously, we reported that lysophosphatidylcholine (LPC), an endogenous lipid, enhances bactericidal activity of human neutrophils via increasing translocation of azurophil granules. However, the precise mechanism of LPC-induced azurophil granule translocation was not fully understood. Treatment of neutrophil with LPC significantly increased CD63 (an azurophil granule marker) surface expression. Interestingly, cytochalasin B, an inhibitor of action polymerization, blocked LPC-induced CD63 surface expression. LPC increased F-actin polymerization. LPC-induced CD63 surface expression was inhibited by both a Rho specific inhibitor, Tat-C3 exoenzyme, and a Rho kinase (ROCK) inhibitor, Y27632 which also inhibited LPC-induced F-actin polymerization. LPC induced Rho-GTP activation. NSC23766, a Rac inhibitor, however, did not affect LPC-induced CD63 surface expression. Theses results suggest a novel regulatory mechanism for azurophil granule translocation where LPC induces translocation of azurophil granules via Rho/ROCK/F-actin polymerization pathway.

• The Korean Journal of Physiology and Pharmacology
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• 제26권4호
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• pp.229-238
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• 2022

Severe bacterial infections are frequently accompanied by depressed neutrophil functions. Thus, agents that increase the microbicidal activity of neutrophils could add to a direct antimicrobial therapy. Lysophosphatidylcholine augments neutrophil bactericidal activity via the glycine (Gly)/glycine receptor (GlyR) α2/TRPM2/p38 mitogen-activated protein kinase (MAPK) pathway. However, the direct effect of glycine on neutrophil bactericidal activity was not reported. In this study, the effect of glycine on neutrophil bactericidal activity was examined. Glycine augmented bactericidal activity of human neutrophils (EC₅₀ = 238 μM) in a strychnine (a GlyR antagonist)-sensitive manner. Glycine augmented bacterial clearance in mice, which was also blocked by strychnine (0.4 mg/kg, s.c.). Glycine enhanced NADPH oxidase-mediated reactive oxygen species (ROS) production and TRPM2-mediated [Ca²⁺]_i increase in neutrophils that had taken up E. coli. Glycine augmented Lucifer yellow uptake (fluid-phase pinocytosis) and azurophil granule-phagosome fusion in neutrophils that had taken up E. coli in an SB203580 (a p38 MAPK inhibitor)-sensitive manner. These findings indicate that glycine augments neutrophil microbicidal activity by enhancing azurophil granule-phagosome fusion via the GlyRα2/ROS/calcium/p38 MAPK pathway. We suggest that glycine could be a useful agent for increasing neutrophil bacterial clearance.

• 대한수의학회지
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• 제12권2호
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• pp.153-164
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• 1972

With an effort to clarify the nature of the azurphil granules which occasionally occur in the circulating lymphocytes, these granules were investigated by examining smear of the peripheral blood of the chikens in various stage of the individual growth and after injection of methylene blue and gentian violet. In addition, the fine structure of these granules were also investigated. The results were: 1. These granules were first occurred in the lymphocytes just after their hatching (0.004%). The proportion of lymphocytes containing these granules were increased with their growth and in adult chicken its occurrence was higher than mammals. 2. Marked variations in its fine structure, particularly in its size and cotents, were noted but they were believed to belong to categories of lysosome of de Duve. 3. Lymphocytes containing azurophil granule were increased after injection of the non-immunogenic substances, such as gentian violet and methylene blue. 4. From the above results, chicken is bettor animal to study theme granules because of its higher occurrence. They are believed to have intimate relationship with bodily cellular reaction against the foreign materials because they are increased after non-immunogenic stimuli.

• Tuberculosis and Respiratory Diseases
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• 제43권3호
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• pp.440-448
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• 1996

Bronchial carcinoid tumors are uncommon, constituting approximately 3-5% of all primary lung cancers. Classification of these tumors has evolved substantially as our understanding of the cellular, biologic, and clinical aspects of these neoplasms has improved. Initially, bronchial carcinoids were thought to be benign and therefore were classified as bronchial adenomas. Currently, however, they are well recognized as having the potential for both local invasion and distant metastatic involvement. Consequently, carcinoid tumors are frankly malignant. Thus bronchial adenoma is a misnomer that should no longer be used for bronchial carcinoids. Most investigators currently favor classifying carcinoid tumors as a type of neuroendocrine neoplasm because of their potential to secrete a variety of chemical substances found in both the central nervous system and the epithelial cells of numerous organs. Bronchial carcinoids are usually characterized by a slow growth pattern and a low incidence of metastasis, and histologically conformed by the azurophil staining and the presence of the characteristic neurosecretary granule on electron microscopy. Atypical carcinoid tumor was first defined by Arrigoni et al, who proposed the following criteria for separation of atypical carcinoid from typical carcinoid tumor : 1) increased mitotic activity with 1 mitotic figure per 1-2 high power fields(or 5-10 mitoses /10 HPF), 2) nuclear pleomorphism, hyperchromatism, and an abnormal nuclear-cytoplasmic ratio, 3) areas of increased cellularity with disorganization of the architecture, and 4) tumor necrosis. In contrast, typical carcinoid tumor may have focal cytologic pleomorphism, but necrosis is absent and mitotic figures are rare. Recently we experienced a case of atypical bronchial carcinoid with multiple distant metastasis, so we report this case with a review of the literature.

• Tuberculosis and Respiratory Diseases
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• 제38권1호
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• pp.74-82
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• 1991

Bronchial carcinoid is one of the unusual tumors of the lung, accounting for 1 percent of all lung tumors. Carcinoids, like small cell carcinomas, are generally considered to be derived from a neurosecretary type of cell of the respiratory epithelium, the Kulchtsky's cell. So, they are no longer classified as bronchial adenoma, and are recently grouped into the neuroendocrine group of tumors, the so-called APUD (Amine Precursor Uptake Decarboxylase) group of tumors. Although usually characterized by a slow growth pattern and a low incidence of metastatic disease, bronchial carcinoids should no longer be considered as beingn, and a much higher malignant behavior has been described with a special destignation of 'atypical carcinoid'. Bronchial carcinoids are histologically confirmed by the azurophil staining and the presence of the characteristic neurosecretary granule on electron microscopy. Recently we experienced two cases of bronchial carcinoid, the first case, being peripheral-located and histologically proven as atypical carcinoid, and the second, being central-located and hitologically typical. So we report these cases with a review of the literature.

• 대한약리학회지
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• 제26권1호
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• pp.51-54
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• 1990

사람 중성구내의 azurophil granule 내에 존재하는 serine protease인 cathepsin G는 정상 반응에서는 항 박테리아 작용을 나타내는데 관여하지만, 이들의 효소활성이 비정상적으로 증가되었을 때는 오히려 인체 정상 조직을 파괴함으로써 rheumatoid arthritis를 비롯한 여러가지 염증성 질환을 야기시킨다고 알려져 있다. 항염증제로 작용하는데 있어서 prostaglandin 합성을 억제하는 작용 이외에 다른 작용 기전이 있는가 하는것은 대단히 흥미있는 연구 과제이었으므로 neutral protease 중의 하나인 cathepsin G와 이 염증반응에 직접적으로 관여하는지 알아보기 위하여 본 연구에서는 두 단계의 크로마토그라피를 거쳐 순수한 cathepsin G를 분리하고, 여러가지 비스테로이드성 항염증제를 이용하여 cathepsin G에 대한 억제 정도를 관찰하였다. 이중 sulindac, salicylate, phenylbutazone, oxyphenbutazone 그리고 salicyluric acid가 각각 4.3mM, 14.3mM, 6.5mM, 11mM, 15mM의 $IC_{50}$로써 cathepsin G의 활성도를 억제하였다. 따라서 NSAIDs의 항염증 작용 기전은 기존에 알려지고 있는 cyclooxygenase 억제에 따른 prostaglanndin 합성, 분비 억제 기전이외에 rheumatoid arthritis 부위에 직접적 원인으로 작용할 가능성이 있는 cathepsin G를 억제 함으로써 조직 파괴를 막는 역할을 하고 있을 가능성이 있는 것으로 사료된다.