• Journal of Periodontal and Implant Science
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• v.25 no.2
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• pp.267-278
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• 1995

Human polymorphonuclear leukocytes(PMN) are the most numerous host cell in periodontal pockets and their presumed role is to form a protective barrier between the bacteria and periodontal tissues. Microbial component LPS activates macrophages to produce $IL-1{\beta}$, $MIP-1{\alpha}$, $-1{\beta}$, $TNF-{\alpha}$ and IL-6, etc. These cytokines have autocrine function to the macrophages, and paracrine function to other cell such as PMN and affect them to produce some biological functions. In the present study, human PMN were tested for the expression of $IL-1{\beta}$ and $MIP-1{\alpha}$ mRNA. Also we performed the receptor binding assay and in vitro assay for the antimicrobial action of HL-60 cell to determine whether HL-60 can replace the peripheral PMN in analyzing the biological functions. PMN were stimulated with $IL-1{\beta}$, TPA, $MIP-1{\alpha}$, LPS, IL-2 and total cytoplasmic RNA were extracted for the northern blot analysis. In order to determine the induction kinetics of $IL-1{\beta}$ or $MIP-1{\alpha}$ mRNA expression, cells were stimulated for 0,1,2,3 hours. We found peak expression of $IL-1{\beta}$ mRNA after 1hr of induction with $IL-1{\beta}$, LPS and after 2hr of induction with TPA. $MIP-l{\alpha}$ also induced but a scarce $IL-l{\beta}$ message from PMN. In contrast to the $IL-l{\beta}$ mRNA expression, $MIP-1{\alpha}$ were not induced from PMN in any culture conditions. Receptors for $MIP-1{\alpha}$ were identified on dibutyryl cyclic AMP(dbcAMP)-treated HL-60 as well as peripheral PMN. dbcAMP treatment significantly enhanced antimicrobial action of undifferentiated HL-60 cell. MIP-1 further increased enhancing effect of dbcAMP. $IL-1{\beta}$, to a lesser extent, also increased dbcAMP-induced enhancing effect of antimicrobial action of HL-60 cell.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.6
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• pp.319-327
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• 2004

This study was aimed at evaluating the effect of defibrotide on the development of the surgically induced reflux esophagitis, on gastric secretion, lipid peroxidation, polymorphonuclear leukocytes (PMNs) accumulation, polymorphonuclear leukocytes adherence, superoxide anion and hydrogen peroxide production in PMNs, scavenge of hydroxyl radical and hydrogen peroxide, cytokine (interleukin-1 ${\beta}$, tumor necrosis $factor-{\alpha}$) production in blood, and intracelluar calcium mobilization in PMNs. Defibrotide did not inhibit the gastric secretion and not change the gastric pH. Treatment of esophagitis rats with defibrotide inhibited lipid peroxidation, and myeloperoxidase (MPO) in the esophagus in comparison with untreated rats. Defibrotide significantly decreased the PMN adherence to superior mesenteric artery endothelium in a dose-dependent manner, Superoxide anion and hydrogen peroxide production in $1{\mu}M$ formylmethionylleucylphenylalanine (fMLP)- or $0.1{\mu}g/ml$ N-phorbol 12-myristate 13-acetate (PMA)-activated PMNs was inhibited by defibrotide in a dose-dependent fashion. Defibrotide effectively scavenged the hydrogen peroxide but did not scavenge the hydroxyl radical. Treatment of esophagitis rats with defibrotide inhibited interleukin-1 ${\beta}$ production in the blood in comparison with untreated rats, but tumor necrosis $factor-{\alpha}$ production was not affected by defibrotide. The fMLP-induced elevation of intracellular calcium in PMNs was inhibited by defibrotide. The results of this study suggest that defibrotide may have partly beneficial protective effects against reflux esophagitis by the inhibition lipid peroxidation, PMNs accumulation, PMNs adherence to endothelium, reactive oxygen species production in PMNs, inflammatory cytokine production(i.e. interleukin-1 ${\beta}$), and intracellular calcium mobilization in PMNs in rats.

• Journal of Veterinary Clinics
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• v.23 no.4
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• pp.393-399
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• 2006

Ketamine, one of general anesthetics for human and veterinary use, is a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist which interferes with the action of excitatory amino acids. It has been reported to impair various leukocyte functions. In this study, the effect of ketamine on the oxidative burst activity (OBA) of canine peripheral blood leukocytes was examined. The OBA of canine peripheral blood phagocytes was analyzed by flow cytometry system. Ketamine at higher concentration such as $1,000{\mu}M$ exhibited a low viability of leukocytes. Thus, ketamine was used at concentration of 10 to $500{\mu}M$ showing no cytotoxic effect and high cell viability. The OBA of leukocytes in the presence or absence of latex beads was analyzed by addition of dihydrorhodamine 123. The direct treatment of ketamine revealed the inhibitory effect on the OBA of peripheral blood polymorphonuclear cells (PMN) and monocyte-rich cells but not peripheral blood mononuclear cells (PBMC) in the presence of latex beads. However, when latex beads were not added to PMN, its OBA was not inhibited by ketamine. The OBA of PMN and monocyte-rich cells but not PBMC in the presence of latex beads was also inhibited by culture supernatant from ketamine-treated- PBMC but not -PMN. But the OBA of PMN in the absence of latex beads was not inhibited by culture supernatant from PBMC treated with ketamine. Therefore, these results suggested that ketamine has the inhibitory effect on the OBA of canine peripheral blood phagocytes such as neutrophils and monocytes during phagocytic response.

• Tuberculosis and Respiratory Diseases
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• v.39 no.3
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• pp.228-235
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• 1992

Background: Although polymorphonuclear leukocytes (PMN) are important in protecting the airways and alveolar surfaces, there is evidence that they can also injure the lung while exercising their defensive role. However it has been unclear whether PMN-induced pneumocyte injury is mediated by their direct cytotoxic effect on target cells or by PMN-derived cytotoxic mediators. On the other hand histamine was known not only to act as an important chemical mediator participated in the pathogenesis of some atotic and allegic disorders, but also to have an inhibitory effect on normal PMN functions. Method: To study the mechanism by which PMN induce pneumocyte injury, we cocultured PMN from four healthy nonsmokers or their PMN-derived supernatants (PMN-SPN) with monolayers of $^{51}Cr$-labeled human A549 pneumocytes and compared PMN-and PMN-SPN-mediated pneumocyte injuries measured by $^{51}Cr$ release assay. We also compared the effects of histamine on each pneumocyte injury. Results: 1) PMN-SPN showed more injurious effect on A549 pneumocytes than that of PMN itself regardless histamine pretreatment of PMN. 2) Pneumocyte injury by PMN with histamine pretreatment was increased or decreased compared with that by PMN without histamine pretreatment, according to histamine concentrations, and PMN stimulating agents and their concentrations. 3) Pneumocyte injury by PMN-SPN with histamine pretreatment tended to be decreased compared with that by PMN-SPN without histamine pretreatment. Conclusion: Our results suggest that PMN-SPN may play more important role in mediating pneumocyte injury than PMN itself and that histamine may partially play a protective role on PMN-induced pneumocyte injury. Alternatively we conclude that the effects of histamine on PMN-induced pneumocyte injury may be affected by microenvironment in vivo.

• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.733-740
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• 1995

This investigation was undertaken to determine the relationship between the amount of polymorphonuclear leukocyte(PMN) enzyme myeloperoxidase(MPO) in gingival crevicular fluid(GCF) collected from active or control site and gingival disease status described by clinical indices(gingival index, papillary bleeding index, pocket depth, periotron unit). The results were as follows : 1. MPO activity/site was greater at active sites than at control sites. 2. According to increasing the clinical parameters, MPO/sites was higher statistically (P<0. 01, P<0.05). 3. High MPO(unit/site) groups was higher statistically than low MPO(unit/site) groups in various clinical parameters. 4. Correlation coefficients between MPO(unit/site) and GI, MPO($unit/{\mu}l$ GCF) and periotron unit were 0.4782, -0.5901, respectively.

• Restorative Dentistry and Endodontics
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• v.30 no.2
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• pp.138-144
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• 2005

This in vitro study monitored MMP-8 production on PMN by stimulated with the following three groups; Sonicated extracts of E. faecalis (SEF), SEF treated with $Ca(OH)_2$ (12.5mg/ml) for 7 days, and lipopolysac-charides(LPS) of E. coli. The level of MMP-8 in each group was immediately measured by ELISA. The data were analyzed with Kruskal-Wallis test and Mann-Whitney U test. In the SEF group, the level of production of MMP-8 was higher than the negative control group in low concentration ($0.05{\mu}g/ml$) of SEF (p < 0.05). but it decreased with an increase in the concentration of SEF (p < 0.05). In the case of SEF treated with $Ca(OH)_2$, all of the MMP levels were higher than negative control group (p < 0.05), but no statistical difference was found among the different SEF concentrations (p > 0.05). All of the levels in E. coli LPS were incresed with increasing concentrations (p < 0.05). According to this study we could summarized as follows: 1. MMP-8 was expressed at low level in untreated PMN group the levels of MMP-8 were upregulated in PMN stimulated by E. coli LPS groups. 2. In the SEF groups, the level of production of MMP-8 decreased with an increase in concentration of SEF (p < 0.05). So E. faecalis may have suppressive effect on the production of MMP-8 by PMN. 3. In the case of SEF treated with $Ca(OH)_2$, all of the MMP levels at different SEF concentrations were higher than untreated PMN group (p < 0.05), but no statistical difference was found among the different SEF concentrations (p > 0.05).

• Biomolecules & Therapeutics
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• v.1 no.2
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• pp.131-136
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• 1993

In the present study, the effect of $HgCl_2$on the function of human peripheral polymorphonuclear leukocytes(PMNs) was examined. PMNs were isolated from human peripheral blood with density centrifugation in Ficoll-Paque. The cells were then incubated with $0.5{\sim}5{\mu}M\;HgCl_2$and glass adherence, chemotactic activity and erythrocyte-antibody rosette forming activity were measured. $HgCl_2$ decreased the function of PMNs in all three aspects tested. $HgCl_2$significantly diminished glass adherence(40.5 {\mu}M: 92{\pm}12%$ (percentage of control, $mean{\pm}$ S.D.); 41 {\mu}M: 46{\pm}11%,$ P<0.01; $3{\mu}M: 35{\pm}7%,$P<0.01;$5{\mu}M:49{\pm}10%,$ P<0.01). Similarly, significant differences were observed in chemotactic activity after $HgCl_2$treatment compared with control (control: $0.95{\pm}0.14mm; 0.5 {\mu}M: 0.91{\pm}0.11 mm; 1 {\mu}M: 0.77{\pm}0.16mm, P<0.05; 3{\mu}M: 0.61{\pm} 0.06mm, P<0.01; 5{\mu}M: 0.15{\pm}0.03 mm, P<0.01).$ Also, 4HgCl_2$decreased the percentage of rosette-forming PMNs, indicating diminished phagocytic activity of PMNs upon $HgCl_2$ exposure compared with control (control: $58{\pm}4%; 1{\mu}M: 53{\pm}4%, p<0.05; 3{\mu}M: 49{\pm}3%, P<0.01; 5{\mu}M: 46{\pm}3%, P<0.01).$ Cell viability was not antered after $HgCl_2$treatment (483{\pm}5%$ viability in control PMNs versus $81{\pm}8%$ viability in $5{\mu}M$ Hg-treated PMNs), suggesting that the impaired PMN function after $HgCl_2$treatment was not due to nonspecific cytotoxicity induced by $HgCl_2$. $HgCl_2$-induced decrease in the function of PMNs may have some implications in depressed host susceptibilityupon bacterial challenge after mercury exposure.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.1
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• pp.43-50
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• 2004

Ischemia followed by reperfusion in the presence of polymorphonuclear leukocytes (PMNs) results in a marked cardiac contractile dysfunction. Amrinone, a specific inhibitor of phosphodiesterase 3, has an antioxidant activity against PMNs. Therefore, we hypothesized that amrinone could attenuate PMNs-Induced cardiac dysfunction by suppression of reactive oxygen species (ROS) produced fby PMNs. In the present study, we examined the effects of amrinone on isolated ischemic (20 min) and reperfused (45 min) rat hearts perfused with PMNs. Amrinone at $25\;{\mu}M$, given to hearts during the first 5 min of reperfusion, significantly improved coronary flow, left ventricular developed pressure (P<0.001), and the maximal rate of development of left ventricular developed pressure (P<0.001), compared with ischemic/reperfused hearts perfused with PMNs in the absence of amrinone. In addition, amrinone significantly reduced myeloperoxidase activity by 50.8%, indicating decreased PMNs infiltration (p< 0.001). Superoxide radical and hydrogen peroxide production were also significantly reduced in fMLP- and PMA-stimulated PMNs pretreated with amrinone. Hydroxyl radical was scavenged by amrinone. fMLP-induced elevation of $[Ca^{2+}]_i$ was also inhibited by amrinone. These results provide evidence that amrinone can significantly attenuate PMN-induced cardiac contractile dysfunction in the ischemic/reperfused rat heart via attenuation of PMNs infiltration into the myocardium and suppression of ROS release by PMNs.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.6
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• pp.579-586
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• 1999

Complement-mediated neutrophil activation has been hypothesized to be an important mechanism of reperfusion injury. It has been proposed that C1 esterase inhibitor (C1 INH) may prevent the complement- dependent activation of polymorphonuclear leukocytes (PMNs) that occurs within postischemic myocardium. Therefore, The effect of C1 INH was examined in neutrophil dependent isolated perfused rat heart model of ischemia (I) (20 min) and reperfusion (R) (45 min). Administration of C1 INH (5 mg/Kg) to I/R hearts in the presence of PMNs $(100{\times}10^6)$ and homologous plasma improved coronary flow and preserved cardiac contractile function (p＜0.001) in comparison to those I/R hearts receiving only vehicle. In addition, C1 INH significantly (p＜0.001) reduced PMN accumulation in the ischemic myocardium as evidenced by an attenuation in myeloperoxidase activity. These findings demonstrate the C1 INH is a potent and effective cardioprotective agent inhibits leukocyte-endothelial interaction and preserves cardiac contractile function and coronary perfusion following myocardial ischemia and reperfusion.

• Journal of Veterinary Clinics
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• v.20 no.3
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• pp.294-301
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• 2003

This study was performed to compare the effects of hydrocolloid(Duoderm$\circledR$, HC in this study) and hydrogel (Nu-Gel$\circledR$, HG in this study) occlusive dressing materials on degree of exudate, wound contraction, epithelialization, and healing of full-thickness skin wound in dogs. Three wounds measuring 2${\times}$2 cm in size were created bilaterally(6 wounds/dog) on the dorsolateral aspect of the trunk of 12 dogs. In each dog, the wounds were treated with HC, HG, and normal saline, respectively. For a 4 week period, the wounds were evaluated gross aspects and histopathological aspects. There were no statistically significant differences between treatment groups in percentage of wound contraction, percentage of epithelialization, and percentage of wound total healing during the first week. Significant differences were first detected on day 14. On day l4(P < 0.01) and 21 (P < 0.05), mean percentage of epithelialization of HG-treated wound was significantly greater than those in HC- and normal saline-treated wound. Mean percentage of wound contraction of HG-treated wound was significantly greater than that in HC- and control wounds on day 21(P< 0.05). On day 21, mean percentage of wound healing of HG-treated wound was significantly greater than that in HC- and control wounds(P < 0.02). On day 1, 4, and 7 after wound creation, although severe infiltration of PMN (polymorphonuclear leukocyte) cells in HC- and control wounds were observed in the subcutis and moderate infiltration of PMN cells in HG-treated wound were observed in the subcutis, we did not detect significant differences. On day 14 after wounding creation, in the wounds treated with HG dressing, epithelial cells were found over the surface, and edema further decreased in the tissue under the wounds, and the granulation tissue was replaced with collagen fibers. On day 21 after wound creation, in HG-treated wound compared with other experimental material-treated wounds, regenerated epidermis covered most of the wound surface, and the granulation tissue was more replaced with collagen fibers than that on day 14. Overall results indicated that the use of hydrogel dressing materials(Nu-Gel$\circledR$) as hydrocolloid dressing (Duoderm$\circledR$) materials and normal saline treatment on full-thickness skin wounds in dogs increased the rate of healing at repair stage.