• The Korean Journal of Physiology and Pharmacology
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• v.26 no.3
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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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• v.26 no.4
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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.

• Korean Journal of Veterinary Research
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• v.12 no.2
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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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• v.43 no.3
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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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• v.38 no.1
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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.

• The Korean Journal of Pharmacology
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• v.26 no.1
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• pp.51-54
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• 1990

Human leukocyte cathepsin-Gs are active participant in the active phase of inflammations like rheumatoid arthritis, emphysema and glomerular injury. Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for treatment of these inflammatory diseases. Mechanism of action of NSAIDs for treatment of inflammatory diseases, especially like rheumatoid arthritis, are known as the inhibitors of prostaglandin synthesis. Inhibitions of the activities of human leukocyte cathepsin-Gs by non-steroidal anti-inflammatory drugs, however, were not same as the known pharmacological effects (inhibition of cyclooxygenase) of these drugs. Among them, especially, sulindac, salicylate, phenylbutazone, oxyphenbutazone, and salicyluric acid inhibited human leukocyte cathepsin-Gs effectively. $IC_{50}s$ of each drug were 4.3mM, 14.3mM, 6.5mM, 11mM and 15mM respectively. The drugs which have same chemical structure and same degree of inhibition effect on cyclooxygenase showed different degree or no effect on inhibition of cathepsin G. These inhibition effect might be, beside of inhibition of cyclooxygenase in the prostaglandin synthesis pathway, another benefitial antiinflammatory effect of NSAIDs by direct protection against tissue destruction in inflammatory diseases.