• Transactions of the KSME C: Technology and Education
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• v.2 no.2
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• pp.73-80
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• 2014

Drug delivery in human upper airway was studied by the numerical simulation of oral airflow. We created an anatomically accurate upper airway model from CT scan data by using a medical image processing software (Mimics). The upper airway was composed of oral cavity, pharynx, larynx, trachea, and second generations of branches. Thin sliced CT data and meticulous refinement of model surface under the ENT doctor's advice provided more sophisticated nasal cavity models. With this 3D upper airway models, numerical simulation was conducted by ANSYS/FLUENT. The steady inspiratory airflows in that model was solved numerically for the case of flow rate of 250 mL/s with drug-laden spray(Q= 20, 40, 60 mL/s). Optimal parameters for mechanical drug aerosol targeting of predetermined areas was to be computed, for a given representative upper airways. From numerical flow visualization results, as flow-rate of drug-laden spray increases, the drag spray residue in oral cavity was increased and the distribution of drug spray in trachea and branches became more homogeneous.

• Environmental and Resource Economics Review
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• v.15 no.5
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• pp.859-884
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• 2006

This study attempts to apply a conjoint analysis, especially using choice experiment, to quantify the economic benefits of health effects(mortality by lung cancer, asthma, acute bronchitis, chronic bronchitis) on air quality improvement in Seoul and Metropolitan area. The yearly willingness to pay for the highest improvement level which is available is estimated as 38,856 won per household. The aggregated value of Seoul and Metropolitan area is measured as 252.8 billion won annually. The quantitative result provided in this study can be usefully employed in policy-making process related to air pollution. Especially, it provides a methodological framework to estimate the benefits for various alternatives in health effects.

• Tuberculosis and Respiratory Diseases
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• v.44 no.4
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• pp.844-852
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• 1997

Background : Recent studies have documented increased release of endothelin(ET) during acute attack of asthma. The purpose of this study is to observe the link between plasma level and urinary excretion of each and changes during acute exacerbation. Method : Plasma and 24 hour urine were collected from sixteen asthmatics during acute exacerbation, twice ; first day of symptomatic exacerbation and two weeks after treatment. Controls were ten healthy normal subjects. All patients were treated with corticosteroid and beta-2 adrenergic agonist on admission. ET was determined by radioimmmunoassay and had 100% cross reactivity with ET-1, 67% with ET-2, 84% with ET-3, and 8% with Big-ET. Results : Plasma ETs were significantly elevated during acute attack of asthma compared with those in remission and controls.,However, there was no significant changes in urine ET concentrations or total ET amounts in 24 hour urine during exacerbation upto two weeks. Those levels of urine ET in asthmatics were still higher than controls. ET concentrations in plasma or urine were not correlated with pulmonary functional parameters and hypoxemia. Conclusion : The findings suggests that increased plasma ETs are related with exaggerated release during acute asthma. Urinary ET excretion is increased in asthma. However, urine ET changes during exacerbation should be observed in a larger and longer scale.

• Tuberculosis and Respiratory Diseases
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• v.44 no.3
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• pp.559-573
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• 1997

Background : Asthma causes recurrent episodes of wheezing, breathlessness, chest tightness, and cough. These symptoms are usually associated with widespread but variable airflow limitation that is partly reversible either spontaneously or with treatment. The inflammation also causes an associated increase in airway responsiveness to a variety of stimuli. Method : Of the 403 adult bronchial asthma patients enrolled from March 1992 to March 1994 in Allergy Clinics of Severance Hospital in Yonsei University, this study reviewed the 97 cases to evaluate the treatment effects and to analyse prognostic factors. The patients were classified to five groups according to treatment responses ; group 1 (non control group) : patients who were not controlled during following up, group 2 (high step treatment group) : patients who were controlled longer than 3 months by step 3 or 4 treatment of "Global initiative for asthma, Global strategy for asthma management and prevention" (NHLBI/WHO) with PFR(%) larger than 80%, group 3 (short term control group) : patients who were controlled less than 1 year by step 1 or 2 treatment of NHLBI/WHO, group 4 (intermediate term control group) : patients who were controlled for more than 1 year but less than 2 years by step 1 or 2 treatment of NHLBI/WHO, group 5 (long term control group) : patients who were controlled for more than 2 years by step 1 or 2 treatment of NHLBI/WHO. Especially the patients who were controlled more than 1 year with negatively converted methacholine test and no eosinophil in sputum were classified to methacholine negative conversion group. We reviewed patients' history, atopy score, total IgE, specific IgE, methacholine PC20 and peripheral blood eosinophil count, pulmonary function test, steroid doses and aggrevation numbers after treatment. Results : On analysis of 98 patients, 20 cases(20.6%) were classified to group 1, 26 cases(26.8%) to group 2, 23 cases(23.7%) to group 3, 15 cases(15.5%) to group 4, and 13 cases(13.4%) to groups 5. There were no differences of sex, asthma type, family history, smoking history, allergic rhinitis and aspirin allergy among the groups. In long term control group, asthma onset age was younger, symptom duration was shorter, and initial pulmonary function was better. The long term control group required lower amounts of oral steroid. had less aggrevation during first 3months after starting treatment and shorter duration from enrollment to control Atopy, allergic skin test, sputum and blood eosinophil, total IgE, nonspecific bronchial responsiveness was not significantly different among the groups. Seven out of 28 patients who were controlled more than 1 years showed negatively converted methachloine test and no eosinophils in the sputum. The mean control duration was $20.3{\pm}9.7$ months and relapse did not occur. Conclusion : Patients who had asthma of onset age younger, shorter symptom duration, better PFT, lower treatment initial steps, lower amounts of steroid needs and less aggravation numbers after starting treatment were classified in the long term control groups compared to the others.

• Clinical and Experimental Pediatrics
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• v.50 no.6
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• pp.556-564
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• 2007

Purpose : We hypothesized that the persisting bronchial hyperresponsiveness (BHR) of adolescents with asthma remission may be controlled mainly by genetic factors, and the BHR of symptomatic asthma by airway inflammation. ${\beta}_2$-adrenoceptor gene is considered to be a candidate gene in the development of BHR. Thus, ${\beta}_2$-adrenoceptor gene polymorphism may be associated with the BHR of adolescents with asthma remission, but not with the BHR of symptomatic asthma. To evaluate this hypothesis, ${\beta}_2$-adrenoceptor gene polymorphism at 2 sites (Arg16-Gly, Gln27-Glu) were examined. Methods : Two hundred two adolescents with BHR ($PC_{20}<18\;mg/mL$) and long term remission (neither asthma-related symptoms nor medication during the previous 2 years) of their asthma (remission group), 182 adolescents with symptomatic asthma (symptomatic group), and 200 healthy adolescents (control group) were studied. Asthma phenotypes were determined using methacholine bronchial provocation test and skin prick test. Genotypes of ${\beta}_2$-adrenoceptor polymorphism were evaluated by PCR-based methods. Results : Gly/Gly allele and Gly16-Gln27 haplotype were more prevalent in the remission group than in the control group (P=0.01, P=0.02), although there was no difference between the symptomatic group and the control group. In the remission group, there was significant difference in geometric mean of $PC_{20}$ among the 3 groups subdivided by the number of Gly16-Gln27 haplotype, showing that the Gly16-Gln27 haplotype was positively associated with BHR. However, no association was found between Gly16-Gln27 haplotype and BHR in the symptomatic group. Conclusion : This study demonstrates that ${\beta}_2$-adrenoceptor polymorphism at amino acid 16 and 27 was associated with BHR persisting in adolescents with asthma remission.

• Tuberculosis and Respiratory Diseases
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• v.39 no.3
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• pp.219-227
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• 1992

Background: Acute and chronic airway inflammation are important in the pathogenesis of bronchial asthma. Corticosteroids have proved to be very effective in the management of asthma. Although the mechanism by which they produce this effect is still debated, suppression of the inflammatory response is thought to be the most likely. Although inhaled steroids are known to be safe and have less side effects than oral steroids, the extent which inhaled steroids have beneficial and the detrimental effects in the treatment of asthma has remained open to question. Budesonide is a recently developed corticosteroid for inhalation treatment with a strong local effect combined with rapid inactivation in the systemic circulation. We set out to look in more detail at the time course of change in bronchial reactivity, clinical symptoms and the effects on the adrenal function during 6 weeks of treatment with budesonide (800 ug per day). Methods: Clinical symptoms, pulmonary function test, histamine $PC_{20}$, serum ACTH and cortisol (8 AM and 4 PM) were measured in 23 allergic asthmatic patients before and after 6 weeks of treatment with budesonide. Results: 1) Pulmonary function test; PEFR, FEV1 and FVC after 6 weeks of treatment with budesonide were higher than those before treatment. 2) Clinical symptoms; Clinical symptoms were significantly improved after 3 weeks and 6 weeks of treatment with budesonide. 3) Histamine provocation; Histamine $PC_{20}$ after 6 weeks of treatment with budesonide was significantly higher than that before treatment. 4) Adrenal function; 6 weeks of budesonide therapy did not significantly affect the level of serum ACTH and cortisol. Conclusion: From these results, it is concluded that budesonide therapy improved the clinical symptoms, pulmonary function and bronchial hyperreactivity after 3 weeks of treatment and the improvement after 6 weeks of treatment was higher than that after 3 weeks of treatment. During 6 weeks of treatment with budesonide, the inhibitory effect on the adrenal function was not obvious.

• Tuberculosis and Respiratory Diseases
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• v.61 no.4
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• pp.339-346
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• 2006

Background: There has no known epidemiologic survey on the frequency of complementary-alternative medicine (CAM) use in the treatment of adult asthma in Korea. This study examined the current use of CAM by asthma patients in Korea. Methods: One hundred adults with asthma, who had been admitted to Kyunghee university hospital between January 2000 and December 2003, were enrolled in this survey. They received a structured questionnaire interview and a clinical assessment of prevalence and pattern of CAM use. Results: 53% patients had an experience of at least one type of CAM during their asthma management. Users of CAM had more hospital visits than those who had never used CAM($1.46{\pm}0.68$ vs. $2.11{\pm}1.20$, p=0.001). Those in their $50^{th}$ decades had more experience of CAM (80%) than the other age groups. The methods of CAM used by our patients are as follows: Diet/nutritional therapy in 35 patients(69%), herbal therapy in 28 patients(53%), acupuncture in 9 patients(17%), moxa treatment in 6 patients(11%), breathing exercises in 1 patient(2%). Conclusions: More than 50% of patients with bronchial asthma have used CAM. A more detailed and large scaled study will be needed to define the actual status of the use of CAM in the treatment for asthma. Inaddition, further research on the scientific validation of the clinical efficacy of CAM in asthma management should be followed.

• Tuberculosis and Respiratory Diseases
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• v.47 no.5
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• pp.629-641
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• 1999

Background: Corticosteroid is most potent and effective anti-inflammatory medication currently available and inhaled form has been used in the long-tenn control of asthma. Fluticasone propionate(Flixotide/Flovent: FP) is highly potent and topically active inhaled corticosteroid and has at least twice the potency of beclomethasone dipropionate(BDP) in the control of asthma. The aim of this study was to compare the efficacy of FP and BDP in several aspects. Method: Fifty patients with asthma were treated in a randomized, parallel group study of 4 weeks duration. During 2-week run-in period $\beta_2$-agonist was administered. After run-in period, FP $500{\mu}g/day$ was administered via Diskhaler or BDP $800{\mu}g/day$ via reservoir dry-power device. During the run-in and treatment period, morning and evening peak expiratory flow rate(PEFR) were measured daily. Daytime and nighttime asthma symptoms, daytime and night-time rescue bronchodilator use were checked daily. $FEV_{1.0}$ and FVC were measured biweekly in both groups. Results: Three patients treated with FP and seven patient treated with BDP were dropped out. Therefore forty patients completed the study. Morning and evening PEFR was increased and diurnal variation of PEFR decreased significantly in both groups. $FEV_{1.0}$ increased significantly in FP treatment group but not in BDP group. There were also improvements in daytime and night-time asthma symptoms, daytime and night-time rescue bronchodilator use in both groups after treatment There were no significant difference between groups in any of the efficacy parameters. Therapeutic effects were demonstrated earlier in patient treated with FP than BDP. Conclusion: In this study, $500{\mu}g/day$ fluticasone propionate was as effective as $800{\mu}g/day$ beclomethasone dipropionate in the control of asthma. Therapeutic effects were demonstrated earlier in patient treated with FP than BDP without adverse effect.

• The Journal of Pediatrics of Korean Medicine
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• v.15 no.1
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• pp.267-270
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• 2001

소아천식은 기도의 만성 염증 및 과민반응을 특징으로 나타내고 있어 염증을 일으키거나 알레르기 반응을 일으키는 물질로부터 차단하는 방법이 효과적임을 현대의학에서 이미 밝히고 있다. 한의학에서는 천증(喘證)에 본디 뿌리 깊은 근원(천유숙근(喘有夙根))이 있다고 간주하여 허약한 체질은 내적인 요인이고, 풍한침습(風寒侵襲)은 유발요인이며, 담음복폐(痰飮伏肺)와 신기휴허(腎氣虧虛)는 재발의 근본이라고 하였다. 본 연구에서는 소아 천식에 구마황(灸麻黃), 은행(銀杏), 건강(乾薑), 오미자(五味子), 백전(白前), 구백부(灸百部), 소자(蘇子) 등을 사용하였고, 경우에 따라 황기(黃?) 혹은 선령비(仙靈脾)를 추가하여 正氣(正氣)를 강화시키는 목적으로 사용하였다. 약리학적 연구에 따르면 마황과 건강, 오미자 등은 모두 기도의 염증세포 침윤(浸潤)를 억제하고 항알레르기 효과가 있으며, 건강과 오미자는 또한 히스타민에 대한 길항효과(拮抗效果)도 있는 것으로 알려져 있다. 은행 추출물은 혈소판 활성화 수용체에 대한 길항작용을 갖고 있으므로 이러한 물질들로 인한 기관지의 경련을 방지하여 천식증상을 왕화시킨다. 구백부(灸百部)는 지해(止咳)효과가 뛰어나다. 소아천식에 대한 치료는 표본동치(標本同治)의 원칙을 지키며, 증상이 완화된 단계에서도 중약 투여를 1-2개월 지속시키는 것이 중요하다. 소아에게 있어서 천식증상이 완화된 후 어혈(瘀血) 상태가 성인에 비해 심하지는 않지만, "구병필어(久病必瘀)"의 결과에 유의할 필요가 있다. 천식이 장기간 지속되면 필히 혈액순환 장애가 수반되므로 천궁(川芎)이나 단삼(丹蔘) 등의 활혈제(活血劑)를 가미하여 사용하면 효과를 높일 수 있다. 결론적으로 소아의 천식은 항염증, 평천(平喘), 화담(火痰), 지해(止咳)와 더불어 보신익기화어(補腎益氣化瘀)의 약물을 병행하여 사용하는 것이 바람직하며, 단순한 중약 투여는 일부 양약에 의한 소아성장에 미치는 영향을 피할 수 있어 더 많은 임상연구가 이어져야 한다.

• Journal of radiological science and technology
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• v.18 no.2
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• pp.37-48
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• 1995

1) 천식 기관지 확장증에서는 기종상 음영이나 기관지가 확장된 상이 있고, 또한 미만성 범세기관지염 5예에서는 미세 반점상 음영이 전체 예에서 인정이 되었다. 2) 폐염에서는 기관지의 확장이나 점액이 고여 침윤음영이 전체 예에 나타나고 있었다. 한편, 간질성 폐염 29예에서는 반점상 음영(불균일 CT치의 상승과 내부에 작은 기관지 확장으로 작은 air상)이 보였다. 폐섬유증 19례에서는 기종상 농포상 음영이나 혈관 기관의 부정 확장, 반점상 음영이 15예로 79 %를 차지하고 있다. 만성 폐기종에서는 기종상, 다발성 농포상 음영, 고목상 혈관이 특징적인 소견이었다. 3) 속립성결핵에서는 작은 입상 음영, 폐결핵 15예에서는 공동 음영 7예, 원형의 융합음영 8예, 침윤음영, 다수의 석회화상, 혈관 기관의 부정 확장 등이 특징적이었다. Aspergillus증에서는 공동 음영 내부에 fungus ball이 보였다. 이상은 미만성 폐질환의 특징적인 CT의 이상 소견에 대해서 검토하였으나, 꼭 일치되는 것은 아니며, 기타 기초적 검사나 임상적인 경과관찰이 필요하였다. 끝으로, 대한방사선기술학회의 발전과 학회원 여러분의 건승을 기원합니다. 그리고 한국과 일본의 우호적인 학술교류가 지속되기를 희망합니다.