• Sleep Medicine and Psychophysiology
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• v.7 no.1
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• pp.27-33
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• 2000

Objectives: The sensitivity and accuracy of thermistor airflow signal has been debated. The purposes of this study were to compare apnea-hypopnea index(AHI) detected from a conventional thermistor signal and a nasal pressure transducer of airflow(NPT), to evaluate the value of NPT for the diagnosis of upper airway resistance syndrome(UARS), and to measure airway pressure fluctuations which produced respiratory arousals in UARS by naso-oro-esophageal manometer catheter. The subjects were 30 patients with obstructive sleep apnea syndrome [mild(540), 10), and 6 UARS patients. Airway resistance arousal in this study was defined as arousals which were not associated with apnea or hypopnea of thermistor signal, but showed significant decrease of nasal airflow pressure just before arousal and a prompt recovery of nasal airflow pressure after arousal. The airway pressure fluctuations were measured during 260 airway resistance arousals observed in 10 patients with OSAS, 2 with UARS. Results: Mean AHIs of patients with OSAS were 33.4 by thermistor and 48.4 by NPT. The AHIs of mild, moderate and severe OSAS groups were 10.2, 32.1, 65.4 respectively by thermistor and 23.1, 45.9, 76.4 by NPT. The mean AHI of patients with UARS was 3.2 by thermistor and 10.8 by NPT. The mean AHI of patients with nonspecific arousals was 2.7 by thermistor and 4.4 by NPT. The mean airway pressure changes during respiratory arousals of different groups were $8.7\;cmH_2O$ in mild OSAS, $11.4\;cmH_2O$ in moderate OSAS, $24.7\;cmH_2O$ in severe OSAS and $6.6\;cmH_2O$ in UARS. Conclusion: The nasal pressure transducer of airflow was more sensitive and accurate for assessing respiratory disturbances of patients with OSAS and was extremely helpful for the diagnosis of UARS without esophageal pressure monitoring. From the results, we would like to propose carefully the NPT diagnostic criteria for sleep disordered breathing as follows: NPT-AHI 5-15 $\rightarrow$ UARS, 15-35 $\rightarrow$ mild OSAS, 35-55 $\rightarrow$ moderate OSAS and >55 $\rightarrow$ severe OSAS.

• Korean Journal of Medicinal Crop Science
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• v.17 no.2
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• pp.90-96
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• 2009

The objective of this study was to investigate the effect of crude ginseng total saponins (CGS) against airway inflammation (AI) and airway hyperresponsiveness (AH) induced by diesel exhaust particles (DEP) in mice. AI and AH were induced by the intratracheal instillation with 0.1 $mg/m{\ell}$ of DEP suspension once a week for 10 weeks combined with ovalbumin (OVA) sensitization. Mice were also treated orally with 75 $mg/m{\ell}$ of CGS, 5 days a week for 10 weeks. Oral CGS treatment decreased in the level of serum immunoglobulin (IgE) and histamine increased by DEP and OVA, and declined respiratory resistance. It also dropped an enhanced infiltration of eosinophils in the bronchoalveolar lavage fluid (BALF) of mice, and an increased T helper type 2 cell derived cytokine levels such as of interleukin (IL)-4, IL-13 and IL-5 in the BALF. However, it did not influence T helper type 1 cytokine such as interferon-gamma in the BALF. These results indicate that CGS may alleviate allergen-related AI and AH in mice and may play an important role in the modulation of asthmatic inflammation.

• Journal of Microbiology
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• v.43 no.1
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• pp.11-16
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• 2005

Matrix metalloproteinase (MMP)-9 plays an important role in the pathogenesis of bronchial asthma. Neovastat, having significant antitumor and antimetastatic properties, is classified as a naturally occurring multifunctional antiangiogenic agent. We evaluated the therapeutic effect of Neovastat on airway inflammation in a mouse model of asthma. BALB/c mice were immunized subcutaneously with ovalbumin (OVA) on days 0, 7, 14, and 21 and challenged with inhaled OVA on days 26, 29, and 31. Neovastat was administrated by gavage (5 mg/kg body weight) three times with 12 h intervals, beginning 30 min before OVA inhalation. On day 32, mice were challenged with inhaled methacholine, and enhanced pause (Penh) was measured as an index of airway hyperresponsiveness. The severity of airway inflammation was determined by differential cell count of bronchoalveolar lavage (BAL) fluid. The MMP-9 concentration in BAL fluid samples was measured by ELISA, and MMP-9 activity was measured by zymography. The untreated asthma group showed an increased inflammatory cell count in BAL fluid and Penh value compared with the normal control group. Mice treated with Neovastat had significantly reduced Penh values and inflammatory cell counts in BAL fluid compared with untreated asthmatic mice. Furthermore, mice treated with Neovastat showed significantly reduced MMP-9 concentrations and activity in BAL fluid. These results demonstrate that Neovastat might have new therapeutic potential for airway asthmatic inflammation.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.1
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• pp.65-71
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• 2015

Asthma is a chronic inflammatory disease characterized by airway hyperresponsiveness (AHR) and reversible airway obstruction. Methacholine (MCh) is widely used in broncho-provocation test to evaluate airway resistance. For experimental investigation, ovalbumin-induced sensitization is frequently used in rodents (Ova-asthma). However, albeit the inflammatory histology and AHR in vivo, it remains unclear whether the MCh sensitivity of airway smooth muscle isolated from Ova-asthma is persistently changed. In this study, the contractions of airways in precision-cut lung slices (PCLS) from control, Ova-asthma, and IL-13 overexpressed transgenic mice (IL-13TG) were compared by analyzing the airway lumen space (AW). The airway resistance in vivo was measured using plethysmograph. AHR and increased inflammatory cells in BAL fluid were confirmed in Ova-asthma and IL-13TG mice. In the PCLS from all three groups, MCh concentration-dependent narrowing of airway lumen (${\Delta}AW$) was observed. In contrast to the AHR in vivo, the $EC_{50}$ of MCh for ${\Delta}AW$ from Ova-asthma and IL-13TG were not different from control, indicating unchanged sensitivity to MCh. Although the AW recovery upon MCh-washout showed sluggish tendency in Ova-asthma, the change was also statistically insignificant. Membrane depolarization-induced ${\Delta}AW$ by 60 mM $K^+$ (60K-contraction) was larger in IL-13TG than control, whereas 60K-contraction of Ova-asthma was unaffected. Furthermore, serotonin-induced ${\Delta}AW$ of Ova-asthma was smaller than control and IL-13TG. Taken together, the AHR in Ova-asthma and IL-13TG are not reflected in the contractility of isolated airways from PCLS. The AHR of the model animals seems to require intrinsic agonists or inflammatory microenvironment that is washable during tissue preparation.

• Journal of Veterinary Science
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• v.21 no.2
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• pp.27.1-27.10
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• 2020

The efficacies of a supraglottic airway device (SGAD) and an endotracheal tube (ETT) in cats under general anesthesia with volume-controlled ventilation (VCV) were compared. Thirty healthy cats were randomly allocated for airway control using either an SGAD or an ETT. Five tidal volumes (6, 8, 10, 12, and 14 mL/kg) were randomly tested, and respiratory rates were adjusted to achieve a minute ventilation of 100 mL/kg/min. The dose of propofol necessary to insert the SGAD or ETT, the static respiratory pressure, leakage during VCV, and end tidal CO₂ (ETCO₂) were recorded. Dosages of propofol and static respiratory measurements for the SGAD and ETT groups were compared using a t-test. The distribution of leakages and hypercapnia (ETCO₂ > 45 mmHg) were compared using Fisher's exact test. A significance level of p < 0.05 was established. No significant difference in dose of propofol was observed between the SGAD and ETT groups (7.1 ± 1.0, 7.3 ± 1.7 mg/kg; p = 0.55). Static resistance pressure of the SGAD (22.0 ± 8.1 cmH₂O/L/sec) was significantly lower than that of the ETT (36.6 ± 12.9 cmH₂O/L/sec; p < 0.01). Of the 75 trials, leakage was more frequent when using an SGAD (8 events) than when using an ETT (1 event; p = 0.03). Hypercapnia occurred more frequently with SGAD (18 events) than with ETT (3 events; p < 0.01). Although intubation with an ETT is the gold standard in small animal anesthesia, the use of an SGAD can reduce airway resistance and the work of breathing. Nonetheless, SGAD had more dead space and the tidal volume for VCV needs adjustment.

• IMMUNE NETWORK
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• v.21 no.3
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• pp.19.1-19.18
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• 2021

Clinical and molecular phenotypes of asthma are complex. The main phenotypes of adult asthma are characterized by eosinophil and/or neutrophil cell dominant airway inflammation that represent distinct clinical features. Upper and lower airways constitute a unique system and their interaction shows functional complementarity. Although human upper airway contains various indigenous commensals and opportunistic pathogenic microbiome, imbalance of this interactions lead to pathogen overgrowth and increased inflammation and airway remodeling. Competition for epithelial cell attachment, different susceptibilities to host defense molecules and antimicrobial peptides, and the production of proinflammatory cytokine and pattern recognition receptors possibly determine the pattern of this inflammation. Exposure to environmental factors, including infection, air pollution, smoking is commonly associated with asthma comorbidity, severity, exacerbation and resistance to anti-microbial and steroid treatment, and these effects may also be modulated by host and microbial genetics. Administration of probiotic, antibiotic and corticosteroid treatment for asthma may modify the composition of resident microbiota and clinical features. This review summarizes the effect of some environmental factors on the upper respiratory microbiome, the interaction between host-microbiome, and potential impact of asthma treatment on the composition of the upper airway microbiome.

• Tuberculosis and Respiratory Diseases
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• v.87 no.3
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• pp.368-377
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• 2024

Background: Bronchiectasis is a chronic respiratory disease that leads to airway inflammation, destruction, and airflow limitation, which reflects its severity. Impulse oscillometry (IOS) is a non-invasive method that uses sound waves to estimate lung function and airway resistance. The aim of this study was to assess the usefulness of IOS in predicting the severity of bronchiectasis. Methods: We retrospectively reviewed the IOS parameters and clinical characteristics in 145 patients diagnosed with bronchiectasis between March 2020 and May 2021. Disease severity was evaluated using the FACED score, and patients were divided into mild and moderate/severe groups. Results: Forty-four patients (30.3%) were in the moderate/severe group, and 101 (69.7%) were in the mild group. Patients with moderate/severe bronchiectasis had a higher airway resistance at 5 Hz (R5), a higher difference between the resistance at 5 and 20 Hz (R5-R20), a higher resonant frequency (Fres), and a higher area of reactance (AX) than patients with mild bronchiectasis. R5 ≥0.43, resistance at 20 Hz (R20) ≥0.234, R5-R20 ≥28.3, AX ≥1.02, reactance at 5 Hz (X5) ≤-0.238, and Fres ≥20.88 revealed significant univariable relationships with bronchiectasis severity (p<0.05). Among these, only X5 ≤-0.238 exhibited a significant multivariable relationship with bronchiectasis severity (p=0.039). The receiver operating characteristic curve for predicting moderate-to-severe bronchiectasis of FACED score based on IOS parameters exhibited an area under the curve of 0.809. Conclusion: The IOS assessed by the disease severity of FACED score can effectively reflect airway resistance and elasticity in bronchiectasis patients and serve as valuable tools for predicting bronchiectasis severity.

• The Korean Journal of Emergency Medical Services
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• v.17 no.3
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• pp.21-28
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• 2013

Purpose: The purpose of this study is to get basic user guidelines of safe and efficient bag-valve-mask application on patients having abnormal pathophysiological pulmonary conditions. Methods: This study was performed by pre-qualified 35 EMS junior and senior students. Participants were instructed to compress ambulatory bag randomly about half, one-third, one-fourth within different airway resistance and pulmonary compliance. Resultant tidal volume and pulmonary wedge pressures on RespiTranier monitor were analysed in relation to pulmonary physiologic index. Results: At least over half compression of bag guaranteed minimal tidal volume regardless of pulmonary conditions. There was no increase of pulmonary wedge pressure above the level of barotrauma on half compression at any pulmonary conditions. Conclusion: Assisted ventilation with ambulatory bag on patients with pathological pulmonary conditions should be over half compressed regardless of respiratory disease entity.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1979.05a
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• pp.8.2-8
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• 1979

Acute obstruction of the upper airway from trachea, a foreign body or Iaryngospasm may lead to death in a few minutes. The immediate restoration of an adequate airway in these patients may be lifesaving. Spontaneous respiration by means of a needle inserted into the trachea was studied in 21 rabbits using 16, 18, and 20 gauge extrcatheters. The results are as follows; 1) Airway resistance was markedly increased in all experimental animals. consequently tidal volume was also significantly decreased, but this seems to be compensatory by increased of respiratory frequency in l6G group. 2) Blood gas analysis revealed adequate pulmonary ventilation through the constricted airway (about 1/3 of normal sized trachea) during 60 minutes. In the other hand, hypercarbia, hypoxemia, and metabolic acidosis were developed in the group with severe constriction of the upper airway (about 1/4-1/6 of normal sized trachea). 3) The further study is postulated to confirm the the possibility of application of needle trcheostomy in man, but the rabbits were tolerable to the constricted airway with a small sized needle (l6G) into the trachea for 60 minutes.

• The Korean Journal of Physiology and Pharmacology
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• v.28 no.3
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• pp.229-237
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• 2024

Cough is a common symptom of several respiratory diseases. However, frequent coughing from acute to chronic often causes great pain to patients. It may turn into cough variant asthma, which seriously affects people's quality of life. For cough treatment, it is dominated by over-the-counter antitussive drugs, such as asmeton, but most currently available antitussive drugs have serious side effects. Thus, there is a great need for the development of new drugs with potent cough suppressant. BALB/c mice were used to construct mice model with cough to investigate the pharmacological effects of pectolinarigenin (PEC). Hematoxylin-eosin and Masson staining were used to assess lung injury and airway remodeling, and ELISA was used to assess the level of inflammatory factor release. In addition, inflammatory cell counts were measured to assess airway inflammation. Airway hyperresponsiveness assay was used to assess respiratory resistance in mice. Finally, we used Western blotting to explore the potential mechanisms of PEC. We found that PEC could alleviate lung tissue injury and reduce the release of inflammatory factors, inhibit of cough frequency and airway wall collagen deposition in mice model with cough. Meanwhile, PEC inhibited the Ras/ERK/c-Fos pathway to exhibit antitussive effect. Therefore, PEC may be a potential drug for cough suppression.