38 research outputs found
Stratifying a Risk for an Increased Variation of Airway Caliber among the Clinically Stable Asthma
ABSTRACTBackgroundRecently, correlations of peak expiratory flow (PEF) variation have been shown to facilitate the prediction of later asthma symptoms and exacerbations. However, it has not been fully examined whether or not any patient characteristics are associated with the residual airway lability in treated asthmatics. The objective of this study is to examine a predictive marker for increased variation of PEF in patients with clinically stable asthma.MethodsWe studied 297 asthmatic patients who were monitored for PEF twice a day. Asthma Control Questionnaire (ACQ), spirometry, and exhaled nitric oxide fraction (FENO) were measured. After the assessment of baseline values, PEF measuring was continued and associations between these clinical markers and later variation of PEF over a week (Min%Max) were investigated.Results17.5% of the subjects showed increased PEF variability (Min%Max < 80%). ACQ, forced expiratory volume in 1 s % of predicted (%FEV1), and FENO were identified as independent predictors of Min%Max < 80%. An ACQ ≥ 0.4 yielded 96% sensitivity and 59% specificity, a %FEV1 ≤ 85% yielded 62% sensitivity and 89% specificity, and a FENO ≥ 40 ppb yielded 75% sensitivity and 90% specificity for identifying the subjects with high variability in PEF. When we combine %FEV1 ≤ 85% and FENO ≥ 40 ppb, this index showed the highest specificity (98%) for increased PEF variability.ConclusionsThese results indicate that ACQ, %FEV1 and FENO can stratify the risk for increased variation in airway caliber among patients with stable asthma. This may help identify subjects in whom further monitoring of lung function fluctuations is indicated
Improvement of Airflow Limitation by Fluticasone Propionate/Salmeterol in Chronic Obstructive Pulmonary Disease: What is the Specific Marker?
Backgrounds: Inhaled corticosteroids (ICS)/inhaled long-acting beta2-agonists (LABA) combination drugs are widely used for the long-term management of chronic obstructive pulmonary disease (COPD). However, COPD is a heterogeneous condition and treatment with ICS is associated with a higher risk of pneumonia. The identification of a specific marker for predicting the efficacy of ICS/LABA on pulmonary function would be useful in the treatment of COPD. Methods: Fourteen COPD patients receiving tiotropium therapy participated consecutively. The relationship between the baseline exhaled nitric oxide (FENO) levels as well as serum markers and changes in pulmonary function by fluticasone propionate (FP)/salmeterol (SAL) were analyzed. Results: FP/SAL therapy significantly improved forced vital capacity, forced expiratory volume in 1 s (FEV1), and the third phase slope of the single nitrogen washout curve (ΔN2) as well as the FENO level. The baseline FENO levels and positive specific IgE (atopy+) were significantly associated with airway obstructive changes assessed by FEV1 and ΔN2. A baseline FENO level >35 ppb yielded 80.0% sensitivity and 66.7% specificity for identifying the subjects with significant improvement in FEV1 (greater than 200 mL). An atopy+ yielded 60.0% sensitivity and 88.9% specificity for an improvement in FEV1. When combined with FENO > 35 ppb and atopy+, it showed 40% sensitivity and 100.0% specificity for FEV1 improvement. Alternatively, COPD subjects with FENO ≤ 35 ppb and atopy− did not show significant improvement in FEV1. Conclusion: Combining FENO and specific IgE may be a useful marker for predicting the response to ICS/LABA on airflow limitation in COPD
Increase of nitrosative stress in patients with eosinophilic pneumonia
<p>Abstract</p> <p>Background</p> <p>Exhaled nitric oxide (NO) production is increased in asthma and reflects the degree of airway inflammation. The alveolar NO concentration (Calv) in interstitial pneumonia is reported to be increased. However, it remains unknown whether NO production is increased and nitrosative stress occurs in eosinophilic pneumonia (EP). We hypothesized that nitrosative stress markers including Calv, inducible type of NO synthase (iNOS), and 3-nitrotyrosine (3-NT), are upregulated in EP.</p> <p>Methods</p> <p>Exhaled NO including fractional exhaled NO (FE<sub>NO</sub>) and Calv was measured in ten healthy subjects, 13 patients with idiopathic pulmonary fibrosis (IPF), and 13 patients with EP. iNOS expression and 3-NT formation were assessed by immunocytochemistory in BALf cells. The exhaled NO, lung function, and systemic inflammatory markers of the EP patients were investigated after corticosteroid treatment for 4 weeks.</p> <p>Results</p> <p>The Calv levels in the EP group (14.4 ± 2.0 ppb) were significantly higher than those in the healthy subjects (5.1 ± 0.6 ppb, p < 0.01) and the IPF groups (6.3 ± 0.6 ppb, p < 0.01) as well as the FE<sub>NO </sub>and the corrected Calv levels (all p < 0.01). More iNOS and 3-NT positive cells were observed in the EP group compared to the healthy subject and IPF patient. The Calv levels had significant positive correlations with both iNOS (r = 0.858, p < 0.05) and 3-NT positive cells (r = 0.924, p < 0.01). Corticosteroid treatment significantly reduced both the FE<sub>NO </sub>(p < 0.05) and the Calv levels (p < 0.01). The magnitude of reduction in the Calv levels had a significant positive correlation with the peripheral blood eosinophil counts (r = 0.802, p < 0.05).</p> <p>Conclusions</p> <p>These results suggested that excessive nitrosative stress occurred in EP and that Calv could be a marker of the disease activity.</p
Predictors for Identifying the Efficacy of Systemic Steroids on Sustained Exhaled Nitric Oxide Elevation in Severe Asthma
Background: Some patients with asthma have high levels of exhaled nitric oxide fraction (FENO) despite inhaled corticosteroids (ICS) therapy. Early studies suggested that this might be explained by the presence of heterogeneous airway inflammation. We aimed to assess the predictors for identifying the efficacy of systemic corticosteroids on residual FEno elevations in severe asthma.
Methods: Twenty severe asthmatics with persistent FENO elevation (≥40 ppb) despite maintenance therapy including high-daily-dose ICS were enrolled. Asthma Control Questionnaire (ACQ), lung function, blood eosinophils, and FENO were assessed before and after 14 days treatment with 0.5 mg/kg oral prednisolone/day.
Results: ACQ, blood eosinophils, FENO level, FVC, FEV1, FEV1/FVC ratio and the slope of the single nitrogen washout curve (∆N2) were significantly improved by treatment with prednisolone. 70% of the subjects showed ≥20% reductions in the FENo levels. The reduction in FENo levels was significantly correlated with the improvements in ACQ p < 0.0001), FVC (p < 0.01), FEV1 (p < 0.0001), and ∆N2 p < 0.05). Among the measurements at baseline, the FENO levels and blood eosinophil numbers were identified as significant predictors of ≥20% reductions in the FEFENO levels by systemic steroid therapy.
Conclusions: Systemic corticosteroids could suppress the residual FENO elevations in more than half of the patients with severe asthma and the reduction in FENO levels was associated with improvements in asthma control and airflow limitation. The FENO levels and blood eosinophil numbers were the predictors of improved residual airway inflammation by systemic steroid therapy in severe asthma
Exhaled Nitric Oxide Cutoff Values for Asthma Diagnosis According to Rhinitis and Smoking Status in Japanese Subjects
Background: Measurement of the exhaled nitric oxide fraction (FEno) has been proposed as a useful diagnostic test for asthma. However, most of the data concerning the fEno cutoff values for the diagnosis of asthma have not yet examined using standard procedures. Furthermore, there is no detailed study that investigated the cutoff values that takes into account patient factors that influence the FEno levels. Methods: FEno was measured in 142 steroid-naive asthmatics and 224 control subjects using an online electrochemical nitric oxide analyzer in accordance with the current guidelines. Subjects without respiratory symptoms and normal spirometric parameters were included in the control group. Asthma was diagnosed on the basis of the presence of significant airway reversibility and/or airway hyperresponsiveness during clinical follow up 6 months after FEno measurements.
Results: FEno was significantly higher in asthmatic patients compared with control subjects (p < 0.01). Based on all study subjects, the receiver operating characteristic curves indicated that the cutoff value of FEno 22 parts per billion (ppb) was associated with the highest combination of sensitivity (90.8%) and specificity (83.9%). Multivariate analysis showed allergic rhinitis, current smoking, and asthma were significant factors influencing the FEno levels. The cutoff values of FEno to discriminate asthma from non-asthma ranged from 18 to 28 ppb depending on rhinitis and smoking status.
Conclusions: The cutoff values presented may be useful for the interpretation of FEno values in the clinical practice
Molecular Mechanism of the Additive Effects of Leukotriene Modifier in Asthmatic Patients Receiving Steroid Therapy
Background: The addition of leukotriene modifier (LM) may be a useful approach for uncontrollable asthma despite treatment with inhaled corticosteroid (ICS), especially in asthmatics comorbid with allergic rhinitis (AR), although little is known about its molecular mechanism. We evaluated the additive effects of LM with ICS on pulmonary function and airway inflammation in asthmatics with or without AR.
Methods: Eighteen uncontrolled steroid-treated asthmatics, nine with and nine without AR, were enrolled. Spirometry, peak expiratory flow (PEF) measurements, and exhaled breath condensate sampling were performed before and 8 weeks after LM administration. The lowest PEF over the course of one week, expressed as a percentage of the highest PEF (Min%Max PEF), was used as an index of fluctuation of the airway caliber. Airway cytokine expression was analyzed with a protein array.
Results: A significant improvement in forced expiratory volume in one second as a percentage of the predicted value (%FEV1) and Min%Max PEF was seen in the subgroup of asthma with AR. Although there was no significant difference in the baseline cytokine values between the groups, the exhaled RANTES level was significantly reduced by LM in the asthma with AR group. The changes in the RANTES level were significantly related to the changes in the %FEV1 and Min%Max PEF values.
Conclusions: LM caused a greater improvement in pulmonary function and airway inflammation in asthmatics with AR. The RANTES-mediated pathway may be involved in the improvement of the airflow limitation and airway lability by LM additive therapy in asthmatics receiving steroid therapy
Development of an automated size-based filtration system for isolation of circulating tumor cells in lung cancer patients.
Circulating tumor cells (CTCs), defined as tumor cells circulating in the peripheral blood of patients with solid tumors, are relatively rare. Diagnosis using CTCs is expected to help in the decision-making for precision cancer medicine. We have developed an automated microcavity array (MCA) system to detect CTCs based on the differences in size and deformability between tumor cells and normal blood cells. Herein, we evaluated the system using blood samples from non-small-cell lung cancer (NSCLC) and small-cell lung cancer (SCLC) patients. To evaluate the recovery of CTCs, preclinical experiments were performed by spiking NSCLC cell lines (NCI-H820, A549, NCI-H23 and NCI-H441) into peripheral whole blood samples from healthy volunteers. The recovery rates were 70% or more in all cell lines. For clinical evaluation, 6 mL of peripheral blood was collected from 50 patients with advanced lung cancer and from 10 healthy donors. Cells recovered on the filter were stained. We defined CTCs as DAPI-positive, cytokeratin-positive, and CD45-negative cells under the fluorescence microscope. The 50 lung cancer patients had a median age of 72 years (range, 48-85 years); 76% had NSCLC and 20% had SCLC, and 14% were at stage III disease whereas 86% were at stage IV. One or more CTCs were detected in 80% of the lung cancer patients (median 2.5). A comparison of the CellSearch system with our MCA system, using the samples from NSCLC patients, confirmed the superiority of our system (median CTC count, 0 versus 11 for CellSearch versus MCA; p = 0.0001, n = 17). The study results suggest that our MCA system has good clinical potential for diagnosing CTCs in lung cancer