• Clinical and Experimental Pediatrics
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• v.46 no.10
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• pp.1013-1018
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• 2003

Purpose : Bronchial hyperresponsiveness(BHR) in asthma is thought to be a consequence of underlying airway inflammation. But the mechanism responsible for persistent BHR in adolescents with long-term asthma remission is poorly understood. The aim of this study was to examine whether BHR in adolescents with asthma remission is associated with peripheral blood eosinophilia and/or increased serum levels of eosinophil cationic protein(ECP). Methods : We studied 35 adolescents with long-term asthma remission(neither symptoms nor medication during the previous two years) who have persistent BHR(remission group) and 35 adolescents with symptomatic asthma(symptomatic group) who were matched for methacholine provocative concentration producing a 20% fall in $FEV_1(PC_{20})$ with subjects in the remission group. The peripheral blood eosinophil counts and serum ECP concentrations were compared between these two groups. Correlations between $PC_{20}$ and peripheral blood eosinophil counts or serum ECP concentrations were assessed in these two groups. Results : Peripheral blood eosinophil counts and serum ECP concentrations were significantly lower in the remission group than in the symptomatic group($273{\pm}108$ vs. $365{\pm}178/{\mu}L$; $16.3{\pm}9.4$ vs. $26.5{\pm}15.1{\mu}g/L$, both, P<0.05). $PC_{20}$ was correlated with peripheral blood eosinophil counts and serum ECP concentrations in the symptomatic group(r=-0.385, P=0.022; r=-0.439, P=0.008), but not in the remission group(r=-0.292, P=0.089; r=-0.243, P=0.159). Conclusion : BHR in adolescents with long-term asthma remission is not associated with peripheral blood eosinophilia or an increase in serum ECP concentration, which suggests that BHR in this clinical setting may not be attributed to airway eosinophilic inflammation. Further studies including direct assessment of airway inflammation are needed to confirm this conclusion.

• Tuberculosis and Respiratory Diseases
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• v.49 no.1
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• pp.37-48
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• 2000

Backgrounds : The pathophysiology of chronic airflow obstruction, such as bronchial asthma, is characterized by mucus hypersecretion, goblet cell hyperplasia(GCH), smooth muscle hypertrophy, and inflammatory cells infiltration. In fatal asthma patients, one distinct findings is mucus hypersecretion due to GCH. However, the mechanisms of GCH in these hypersecretory diseases remain still unknown. In this study, a rat model was rapidly induced with GCH by instillation of $TiO_2$, intratracheally. We intend to confirm GCH and association of concomitant inflammatory cells infiltration and to observe the effect of potent antiinflammatory agent, that is dexamethasone, on GCH with inflammatory cells. Methods : Twenty-one 8-weeks-old male Sprague-Dawley rats were divided into three groups. Endotoxinfree water was instilled intratracheally in group 1(control) ; $TiO_2$, was instilled in the group 2 ; and dexamethasone was injected intraperitoneally to group 3 before $TiO_2$ instillation. After 120 hours, all rats were sacrificed, and trachea, bronchi, and lungs were resected respectively. These tissues were made as paraffin blocks and stained as PAS for goblet cells and Luna stain for eosinophils. We calculated the ratio of goblet cell to respiratory epithelium and number of infiltrated eosinophils from each tissue. Results : (1) Fraction of goblet cells was significantly increased in group 2 than in group 1 in the trachea and in the main bronchus. (10.19$\pm$11.33% vs 4.09$\pm$8.28%, p<0.01 and 34.09$\pm$23.91% vs 3.61$\pm$4.84%, p<0.01, respectively). (2) Eosinophils were significantly increased in the airway of group 2 than that of group 1. (5.43$\pm$3.84% vs 0.17$\pm$0.47 in trachea and 47.71$\pm$16.91 vs 2.71$\pm$1.96 in main bronchi). (3) There was a positive correlation between goblet cells and eosinophils(r=0.719, p=0.001). (4) There was significant difference in the decrease of goblet cells after dexamethasone injection between group 2 and group 3 (p<0.01). Also, infiltration of eosinophils was suppressed by dexamethasone. Conclusion : We made an animal model of $TiO_2$-induced goblet cell hyperplasia. GCH was observed mainly in the main bronchi with concomitant eosinophilic infiltration. Both goblet cell hyperplasia and eosinophilic infiltration were suppressed by dexamethasone. This animal model may serve as a useful tool in understanding of the mechanism of GCH in chronic airway diseases.

• Tuberculosis and Respiratory Diseases
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• v.48 no.6
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• pp.898-908
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• 2000

Background : Eotaxin a CC chemokine specific for eosinophils, is implicated in the pathogenesis of asthma by recruiting eosinophils into the airways. Theophylline has been used for the treatment of asthma and recently was proposed to have an anti-inflammatory action. The aim of this study is to examine whether theophylline may inhibit the eosinophilic airway inflammation by reducing the expression of eotaxin. Methods : The expression of eotaxin mRNA was assessed by Northern analysis in A549 cells 4 h after stimulation with TNF-$\alpha$ or IL-1$\beta$. And then, theophylline was added to A549 cells stimulated with 0.1 ng/mL IL-1$\beta$. Results : Eotaxin mRNA expression rates induced by 0.1, 1, 10 ng/mL TNF-$\alpha$ as compared with $\beta$-actin, were 7%, 22%. 28%, respectively. Eotaxin mRNA expression rates induced by 0.01, 0.1, 1, 10 ng/mL IL-1$\beta$, as compared with $\beta$-actin, were 10%, 42%, 63%, 72%, respectively. Eotaxin mRNA expression rates after the addition of 0, 0.001, 0.01, 0.1 ${\mu}M$ dexamethasone induced by 10 ng/mL TNF-$\alpha$ as compared with $\beta$-actin, were 27%, 18%, 8%, respectively. Eotaxin mRNA expression rate after the addition of 0, 0.001, 0.01, 0.1 ${\mu}M$ dexamethasone induced by 0.1 ng/mL IL-1$\beta$ as compared with $\beta$-actin, were 43%, 47%, 12%, 8%, respectively. Eotaxin mRNA expression rates after the addition of 0, 0.001, 0.01, 0.1, 1, 10 mM theophylline induced by 0.1 ng/mL IL-1$\beta$, as compared with $\beta$-actin, were 48%, 40%, 33%, 22%, 16%, 14%, respectively. Conclusion : These results suggest that theophylline may reduce eosinophil infiltration of the airway at least in part by reducing the expression of eotaxin under the conditions of these experiments.

• Tuberculosis and Respiratory Diseases
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• v.46 no.2
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• pp.175-184
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• 1999

Background: Bronchial asthma is characterized by chronic eosinophilic inflammatory airway disease associated with bronchial hyperresponsiveness and reversible airway obstruction. Bronchial inflammation in asthma may depend in part on the activation of T helper lymphocytes that elaborate proinflammatory cytokines. T helper (Th) lymphocytes can be divided into two categories; Th1 lymphocytes, which secrete IL-2, IL-12 and IFN-$\gamma$, and Th2 lymphocytes, which secrete IL-4, IL-5, IL-6 and IL-10. Th2 lymphocytes appear to induce allergic responses, whereas Th1 lymphocytes induce delayed-type hypersensitivity response. Some infections, such as tuberculosis, cultivate a Th1 immunological environment and inhibit Th2 lymphocytes function. The presence of such infections might inhibit Th2 immune responses and thus protect development of atopic diseases. Method: 15 patients with allergic bronchial asthma, 10 patients with intrinsic bronchial asthma, and 10 healthy volunteers were studied. The serum concentrations of IFN-$\gamma$, IL-12, IL-4, IL-5, and IL-10 were measured by ELISA method and tuberculin skin test was estimated in different groups. Results: The positive response rates of tuberculin test were 46.7% in patients with allergic asthma, 100% in patients with intrinsic asthma and 60% in normal controls. The positive response rates were significantly lower in patients with allergic asthma than those of in patients with intrinsic asthma (p<0.05). Degree of responses to tuberculin test were $12.0{\pm}9.6mm$ in patients with allergic asthma, $18.4{\pm}4.5mm$ in patients with intrinsic asthma and $10.9{\pm}8.8mm$ in normal controls. The degree of responses were significantly reduced in patients with allergic asthma than those of patients with intrinsic asthma (p<0.05). The serum levels of IL-5 in patients with allergic asthma were significantly higher than in patients with intrinsic asthma and normal controls (p<0.05), although it was insignificant. the serum levels of IL-4 and IL-10 in patients with allergic asthma were higher than that of intrinsic asthma and normal controls. The serum levels of IL-12 and IFN-$\gamma$ in patients with allergic asthma and intrinsic asthma were significantly lower than those in normal controls(p<0.05). The serum levels of total immunoglobulin E (IgE) and peripheral blood eosinophile counts in patients with allergic asthma were significantly higher than those in normal controls. Peripheral blood esinophil counts had a significant correlation with the serum levels of total IgE, IL-5 and IL-10 in patients with allergic asthma (p<0.05). Conclusion: These results have showed that Th1 lymphocyte functions were lowered and Th2 lymphocyte functions were elevated in patients with allergic asthma than those in normal controls. Suppression of Th1 lymphocyte functions by activation of Th2 lymphocyte might be one of the important aspects of pathogenesis in allergic bronchial asthma.

• Clinical and Experimental Pediatrics
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• v.50 no.3
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• pp.284-291
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• 2007

Purpose : Theophylline has recently been reported to have concurrent anti-inflammatory effects at low therapeutic plasma concentrations which are below the doses at which significants, clinically useful bronchodilatation is evident. Sustained-release formulation in capsule and dry syrup forms were developed to reduce its adverse effects and improve its clinical effects. We compared the therapeutic effects of theophylline dry syrup and capsules in children with mild asthma. Methods : Ninety children with mild asthma were randomized to receive either theophylline dry syrup (n=44) or theophylline capsules (n=46); 4 mg per kilogram of body weight, twice a day, for 12 weeks. Baseline and serial measurements of daytime and nighttime asthma symptom score were performed. Compliance scores, drug swallowing scores, and drug usability scores were measured every 4 weeks. Each scoring was rated on a scale of 0-4. Serum theophylline concentration were measured at 4 and at 12 weeks. To examine the anti-inflammatory effect of theophylline on asthma, Serum eosinophilic cationic protein as a marker of airway inflammation caused by eosinophil was measured 12 weeks pre- and post-administration. Results : The daytime and nighttime asthma symptom scores of the two groups after 4 weeks significantly improved over the baseline score. Daytime and nighttime asthma symptom scores in the dry syrup group were statistically lower at all time points except for the nighttime symptom scores at 4 weeks. Compliance scores, drug swallowing scores, and drug usability scores in the dry syrup group were significantly higher at the end time point. Only in the dry syrup group was the serum ECP at the end time point statistically lower than baseline. Conclusion : Low-dose sustained-release theophylline may be safe and effective in bronchial asthma and this effect may be mediated by its anti-inflammatory action mechanisms. Especially, when used in children with asthma, dry syrup formulation is recommended because of its higher compliance than capsule formulation.