Oxide In Air Research Articles

EPOC y asma

Chronic obstructive pulmonary disease and asthma are both highly prevalent inflammatory diseases characterized by airway obstruction with distinct pathogenic mechanisms and different degrees of response to antiinflammatory therapy. However, forms of presentation that show overlap between both diseases and which are not clearly represented in clinical trials are frequently encountered in clinical practice. These patients may show accelerated loss of pulmonary function and have a worse prognosis. Therefore their early identification is essential. Biomarkers such as bronchial hyperreactivity or nitric oxide in exhaled air have yielded discrepant results. Phenotypic characterization will allow treatment with inhaled corticosteroids to be individually tailored and optimized.

Analysis of Nitrous Oxide and Helium in Air: Greenhouse Gas Inventory

Analysis of Nitrous Oxide and Helium in Air: Greenhouse Gas Inventory

Utility of exhaled nitric oxide in the diagnosis and management of asthma

The fraction of nitric oxide in exhaled air (FeNO) is elevated in the presence of airway inflammation, and it may be a useful biomarker in asthma. The purpose of the present review is to highlight the current literature investigating the use of exhaled nitric oxide in the diagnosis and management of asthma. The measurement of exhaled nitric oxide has been studied in normal populations and in asthmatics. FeNO appears to be a useful screening tool for asthma, although nondisease factors may confound the interpretation of an elevated FeNO level. Clinical trials investigating the use of FeNO measurements in predicting asthma exacerbation and tailoring maintenance therapy have had varying success. Further studies incorporating individualized FeNO profiles into treatment algorithms are needed. FeNO shows promise as a tool in the diagnosis and treatment of asthma. However, further studies are needed to address outstanding questions about its exact role in guiding asthma management.

Nitric oxide in exhaled air as a marker of bronchial asthma control

Background. To study the clinical value of determining NO in exhaled air in patients with bronchial asthma (BA), as well as its role as marker of asthma control and the relationship with other indicators of BA control. Materials and methods. 114 patients with BA (age 18 to 82) have been examined. Clinical and specific allergical surveys, spirometry and bronchial hyperresponsiveness have been performed. The level of NOex has been measured by NIOX MINO device; Aerocrine AB, Sweden. Asthma control determined by using the ACT-test. Results. It was found that NOex in patients with atopic BA statistically was significantly (p=0,0008) higher than in the healthy control group, the same in patients with nonatopic В A (p=0,00419). The existence of statistically significant correlations between the level of NOex and phase of BA, level NOex and spirometry, NOex and the ACT-test for patients with atopic BA was found. Reducing NOex >20% in response to the correction of the asthma therapy is a sign of achieving asthma control, OR=3,18; 0:1,13-8,92. Conclusion. NOex can be in use as an indicator of control in patients with atopic BA, that statistically significantly correlate with the level of asthma control determined by the doctor (phase of BA), the level of control, determined by the patient (ACT-test), as well as a spirometry (FEV ). NOex is a sensitive marker of response to anti-inflammatory asthma therapy.

Acute Health Effects of Commuters’ Exposure to Air Pollution

ISEE-0670 Background and Objective: People spend a significant amount of time in traffic, during which they are exposed to high levels of air pollution. Very few studies measured acute health effects after exposure in traffic. The TRAVEL study was designed to study exposure and related acute health effects of people commuting by bike, car and bus. Methods: From June 2007 till June 2008 volunteers repeatedly travelled for two hours by bus, car or bike on a fixed route in the city of Arnhem. During the commute we measured the PM10 concentration using Harvard Impactors and Particle Number Count (PNC) using a portable condensation particle counter (TSI CPC3007). Soot was measured on the PM10 filter using a smoke stain reflectometer. Before and six hours after exposure we measured nitrogen oxide in exhaled air (FeNO) and high-sensitivity C-reactive protein (CRP) plasma levels in the volunteers. Results: During the 47 measurement days we collected 357 pre and post health measurements of 34 healthy, non-smoking, adult volunteers. Two hour mean exposure to PNCs ranged from 14000 to 91000 particles/cm3 (mean 40000 particles/cm3), PM10 exposure ranged from 16 to 423 μg/m3 (mean 54 μg/m3), and soot exposure from 1.6 to 31 ± 10-5/m (mean 7.2 ± 10−5/m). FeNO levels were on average 19 ppb, the difference in post and pre FeNO ranged from −35 to 10 (mean: −1.5 ppb). CRP levels were on average 1.21 mg/L, the difference in post and pre CRP ranged from −2.4 to 6.5 (mean: 0.0 mg/L). Using mixed model analysis, we found no associations between exposure to PNC, PM10 and soot and differences in post-pre levels of FeNO and CRP. Conclusion: Commuters’ exposure to PNC, PM10 and soot was not associated with FeNO, a marker of airway inflammation, and plasma CRP, a marker of systemic inflammation.

Effects of Short-Term Exposure to Ozone on Alveolar Nitric Oxide

ISEE-0338 Background and Objective: Exposure to ambient air pollutants has been shown to induce airway inflammation. Measurement of fraction of nitric oxide in exhaled air (FENO) enables the calculation of the production of alveolar NO which has been suggested as a marker of distal airway inflammation. The aim of the study was to estimate whether short- term exposure to O3, NO2 and PM10 was associated with an increase of alveolar NO, a possible marker of inflammation in distal airways. Methods: In this cross-sectional study we investigated 1606 adults in the age 25 to 75 years living in Göteborg, Sweden. Examination included FENO at flow-rates of 50, 100 and 270 mL/s and blood samples and a respiratory questionnaire. Alveolar NO was estimated by using Tsoukias two-compartment model. Atopy was defined as a positive Phadiatiopeâ -test. PM10 and O3 concentrations were measured at an urban background monitoring site and for cumulative mean exposure for 3, 24 and 120 hours were calculated. Ordinary least square regression was used to model the relation between FENO and alveolar NO and each of the studied pollutants, adjusted for potential confounding factors. Results: We found that an increase of one IQR in the 24 hour and 120 hour cumulative average of O3 (corresponding to 44.3 μg/m3 and 25.4 μg/m3) was associated with an increase in alveolar NO of 1.6% (95% CI 0.5–2.6) and 2.0% (95% CI 0.9–3.0). The effect was most pronounced in non-smoking non-atopic subjects. Alveolar NO remained significantly elevated for five days after exposure. Exposure to NO2 and PM10 did not affect alveolar NO or FENO. Conclusions: Exposure to ozone appears to give rise to a small increase in alveolar nitric oxide, a possible marker for airway inflammation in the distal airways.

Exhaled nitric oxide levels in asthma: Personal best versus reference values

Factors affecting the fraction of nitric oxide in exhaled air (FE(NO)) are multiple. Interpreting values when assessing airways disease may be problematic. Clinically optimum levels have not been defined. We aimed to establish the relationship between predicted values for FE(NO) obtained from equations by Olin et al, Travers et al, and Dressel et al, and normalized levels after oral prednisone. We also compared postprednisone FE(NO) levels with those obtained during optimized treatment with inhaled fluticasone. Data were obtained before and after a trial of oral prednisone (30mg/d for 14 days), and also from a previously published study in which patients had their dose of inhaled corticosteroid adjusted using either FE(NO) or symptoms/lung function to optimize treatment. Seventy-three patients completed the study. The geometric mean FE(NO) after prednisone (17.7 parts per billion [ppb]; 95% CI, 15.5-20.2) was significantly lower than mean FE(NO) at the optimized fluticasone dose (20.2 ppb; 95% CI, 17.1-23.8; P=.04) and at loss of control (27.6 ppb; 95% CI, 22.8-33.4; P < .001). FE(NO) levels after prednisone did not differ significantly from the predicted values of Olin et al (16.8 ppb, 95% CI, 16.0-17.5; P=.44), but were significantly lower than values of Travers et al (predicted, 21.5 ppb; 95% CI, 20.9-22.2; P=.005) and Dressel et al (predicted, 27.8 ppb; 95% CI, 26.7-28.9; P < .001). Optimum FE(NO) levels are best established by using oral rather than inhaled steroid treatment, and these approximate to predicted values from the reference equation by Olin et al. However, at optimized doses of inhaled corticosteroid, although FE(NO) levels were higher than predicted, asthma was well controlled. Targeting FE(NO) on reference values is not justified.

The mutagenic effect of low concentrations of ethylene oxide in air

The mutagenic effect of low concentrations of ethylene oxide in air

Eosinophils in induced sputum versus nitric oxide in exhaled air: clinical utility in bronchial asthma

Assessment of eosinophils in induced sputum can help to optimize anti-inflammatory therapy in bronchial asthma, but this is a very demanding technique. The aim of the study is to compare nitric oxide in exhaled air (FeNO), an easy to measure inflammatory biomarker, with eosinophils in sputum in terms of relationship with clinical and functional parameters. 106 asthmatic patients (50 in anti-inflammatory therapy [AB+] and 56 without it [AB-]) and 15 controls were included. After filling a clinical questionnaire, FeNO measurement, forced spirometry and sputum induction by bronchial challenge with hypertonic saline solution were performed. Adequate measurements of FeNO and eosinophils were obtained in 100% and 81% of the patients, respectively. FENO w were higher for AB- compared to AB+ and controls. The percentage of eosinophils in sputum was higher in asthmatic patients compared to controls but without differences between both asthmatics groups and was well correlated with the slope of the dose-response curve of bronchial challenge. In the AB- group, FeNO and eosinophils were well correlated with asthma control level. FENO measurement is readily available and well correlated with clinical and functional markers asthma expression. Anti-inflammatory therapy blunts FeNO levels compromising its utility in the long-term follow-up of asthma patients.

Eosinofilia en esputo versus óxido nítrico en aire exhalado: aplicación clínica en el asma

Background. Assessment of eosinophils in induced sputum can help to optimize anti-inflammatory therapy in bronchial asthma, but this is a very demanding technique. The aim of the study is to compare nitric oxide in exhaled air (FeNO), an easy to measure inflammatory biomarker, with eosinophils in sputum in terms of relationship with clinical and functional parameters. Methods. 106 asthmatic patients (50 in anti-inflammatory therapy [AB+] and 56 without it [AB-]) and 15 controls were included. After filling a clinical questionnaire, FeNO measurement, forced spirometry and sputum induction by bronchial challenge with hypertonic saline solution were performed. Results. Adequate measurements of FeNO and eosinophils were obtained in 100% and 81% of the patients, respectively. FENO w were higher for AB- compared to AB+ and controls. The percentage of eosinophils in sputum was higher in asthmatic patients compared to controls but without differences between both asthmatics groups and was well correlated with the slope of the dose-response curve of bronchial challenge. In the AB- group, FeNO and eosinophils were well correlated with asthma control level. Conclusion. FENO measurement is readily available and well correlated with clinical and functional markers asthma expression. Anti-inflammatory therapy blunts FeNO levels compromising its utility in the long-term follow-up of asthma patients.

Biomarker bei infektiösen und nicht infektiösen Lungenerkrankungen außer Malignome

Biological markers in various compartments of the human body have demonstrated potential value in diagnosis, prediction, guidance of therapy as well as in monitoring the clinical course of diseases of the airways and the lung. But only certain surrogate parameters are from clinical value, such as procalcitonin in pneumonia and sepsis, alpha-1-antitrypsin to diagnose alpha-1-antitrypsin deficiency, D-Dimers to detect emboli, nitric oxide in exhaled air in asthma, or isolation of germs from sputum to guide antibiotic treatment. Quantification of numerous markers in exhaled breath condensate or the detection of compounds in exhaled air are more recent attempts to further elucidate those biomarkers for clinical use. In general, biomarkers have an important supportive value in addition to routine diagnostic methods. The article reviews recent data regarding the usefulness of markers in non-malignant pulmonary diseases.

Nitrogen oxide air pollutants interfere with the measurement of nitric oxide using 2,3-diaminonaphthalene: Reduction of background interference

Nitrite, a stable metabolite of nitric oxide (NO), is measured fluorometrically as an indicator of NO production using 2,3-diaminonaphthalene. In cultured cells, it has been believed that a longer period of incubation improves the detection sensitivity because of the accumulation of nitrite formed from NO in culture media. However, here we show that nitrite formed from nitrogen oxide air pollutants accumulates continuously in culture media during the incubation and interferes with the measurement of NO as nitrite. Thus, a proper period of incubation is important to allow maximum nitrite signals from NO with minimum background nitrite from the air.

EEG Entropy Values During Isoflurane, Sevoflurane and Halothane Anesthesia With and Without Nitrous Oxide

We hypothesized that like bispectral index, entropy may be anesthetic agent specific. We carried out a study to assess the entropy values of different anesthetics at equi-minimal alveolar concentrations (MACs) with air and nitrous oxide as carrier gases. Thirty adult patients undergoing spine surgery were randomized to receive halothane, isoflurane, or sevoflurane, in 2 stages, (a) with air/oxygen mixture (2:1) and (b) in nitrous oxide/oxygen (2:1). Heart rate, mean arterial blood pressure, response entropy (RE), and state entropy (SE) were noted at 1.0 and 1.5 MACs for each agent. Statistical analysis was done using the 2-way analysis of variance followed by Bonferroni correction and Student t test for paired data. P value of less than 0.05 were considered significant. The demographics and baseline values of heart rate, mean arterial blood pressure, RE, and SE were comparable. Changing from air/oxygen as carrier gas to 66% nitrous oxide in oxygen resulted in significant increase in both RE and SE at 1.0 MAC for all the agents (P<0.05). Among the agents, it was found that both RE and SE values were significantly higher during halothane anesthesia as compared with sevoflurane and isoflurane (P<0.05). At 1.5 MAC for all agents, after addition of nitrous oxide, there was an insignificant reduction in both RE and SE (P>0.05). Again the values of RE and SE remained high for halothane as compared with isoflurane and sevoflurane. In conclusion, our data suggest a possibility of misinterpretation of anesthetic hypnosis when entropy values increase with addition of nitrous oxide to 1 MAC isoflurane and sevoflurane.

Rotary Welder for Hot Billets

The use of two-piece billets in aluminium extrusion is often viewed as a necessary evil. A heating system that provides two-piece billets to the press can provide better ingot utilization than a heater which provides single-piece billets. The issues associated with the handling and extruding of two-piece billets are accepted as the price of improved ingot utilization. With the rotary welder, the end of each log segment is joined to the front of the following log by friction welding. The combination of the rotation of the short piece and the pressure applied creates a bond that will maintain one-piece integrity as the billet is conveyed to the press and loaded into the container. The handling issues associated with two-piece billets are eliminated. A unique re-cut cycle removes contaminants from the two weld faces immediately prior to welding. The two ends are precisely aligned and the saw makes a cut that removes the face of the remaining piece and the face of the following log. This re-cut removes debris, oxide and potential trapped air from a less than perfect cut at the cast house. The welding is then performed with the two freshly cut faces. The metallurgical performance is improved by the removal of debris and oxide on the faces. This allows the use of welded billets in some applications that previously required single-piece billets to achieve the necessary structural integrity.

Determining the Alveolar Component of Nitric Oxide in Exhaled Air: Procedures and Reference Values for Healthy Persons

Nitric oxide (NO) production has been described using a 2-compartment model for the synthesis and movement of NO in both the alveoli and the airways. The alveolar concentration of NO (Ca NO), an indirect marker of the inflammatory state of the distal portions of the lung, can be deduced through exhalation at multiple flow rates. Our objective was to determine reference values for Ca NO. The fraction of exhaled NO (Fe NO) was measured in 33 healthy individuals at a rate of 50 mL/s; the subjects then exhaled at 10, 30, 100, and 200 mL/s to calculate Ca NO. A chemiluminescence analyzer (NIOX Aerocrine) was used to perform the measurements. The mean (SD) Fe NO was 15 (6) ppb. The mean Ca NO was 3.04 (1.30) ppb. These values of Ca NO measured in healthy individuals will allow us to analyze alveolar inflammatory behavior in respiratory and systemic processes.

Hydrogen production from coal using coal direct chemical looping and syngas chemical looping combustion systems: Assessment of system operation and resource requirements

Coal direct chemical looping (CDCL) substitutes the gasification process in syngas chemical looping (SCL), thus eliminating the need for higher oxygen consumption. In this study, operating conditions are assessed for CDCL and SCL, directed towards hydrogen production from coal. The main objective is to increase the overall H2/CO2 ratio for a given amount of coal, based on the various conditions. The operating variables considered as part of a resource optimization analysis include: (i) inlet conditions to the primary reactors, (ii) minimum resource requirements (air, steam and iron oxide), (iii) hydrogen-to-component ratios, and (iv) effect of coal carrier gas. The results suggest that CDCL has a higher hydrogen-to-CO2 ratio than SCL along with advantages such as low overall resource requirements (steam and air) and fewer intermediate processes. The coal carrier gas affects the hydrogen production only in the SCL system by altering the composition of syngas induced by gasifier temperature variation.

Low-dose theophylline enhances the anti-inflammatory effects of steroids during exacerbations of COPD

Background:Chronic obstructive pulmonary disease (COPD) is characterised by an abnormal inflammatory response mainly to cigarette smoke that flares up during exacerbations of the disease (ECOPD). Reduced activity of histone deacetylases...

The role of surface treatments on the bond between acrylic denture base and teeth

The aim of this study was to compare the bond strength between acrylic denture base and teeth subjected to 6 surface treatments. Ninety-six specimens were made with poly(methylmethacrylate) teeth bonded to a microwave-polymerized acrylic denture base material. The specimens were distributed into 6 groups (n=16) according to surface treatments: CT - no treatment (control); MN - methylmethacrylate monomer etching; AO - 50-microm-particle aluminum oxide air abrasion; BR - glaze removal with a round bur; ST - surface grinding with an aluminum oxide abrasive stone; group CV - cavity preparation (diatorics). The control and surface-treated groups were subjected to a compressive load at 45 masculine angle to the long axis of the teeth. Data were analyzed by one-way ANOVA, followed by Scheffé's test (p<0.05). Bond strength means and (SD) in kgf for groups were: CT: 18.19 (7.14), MN: 18.34 (5.28), AO: 23.82 (5.40), BR: 23.30 (4.79), ST: 25.39 (7.80) and CV: 17.48 (7.17). There was statistically significant difference (p=0.037997) only between ST and CV. In conclusion, ridge lap surface grinding with an aluminum oxide abrasive stone provided the highest bond strength, though it differed significantly only when compared to diatorics. The other surface treatments provided similar bond between the acrylic denture base and teeth.

Nitric oxide in exhaled and aspirated nasal air as an objective measure of human response to indoor air pollution

The concentration of nitric oxide (NO) in exhaled and aspirated nasal air was used to objectively assess human response to indoor air pollutants in a climate chamber exposure experiment. The concentration of NO was measured before exposure, after 2, and 4.5 h of exposure, using a chemiluminescence NO analyzer. Sixteen healthy female subjects were exposed to two indoor air pollutants and to a clean reference condition for 4.5 h. Subjective assessments of the environment were obtained by questionnaires. After exposure (4.5 h) to the two polluted conditions a small increase in NO concentration in exhaled air was observed. After exposure to the reference condition the mean NO concentration was significantly reduced compared to pre-exposure. Together these changes resulted in significant differences in exhaled NO between exposure to reference and polluted conditions. NO in nasal air was not affected by the exposures. The results may indicate an association between polluted indoor air and subclinical inflammation. Measurement of nitric oxide in exhaled air is a possible objective marker of subclinical inflammation in healthy adults.

Montelukast as Add-on Therapy to β-Agonists and Late Airway Response

Rosewich M, Rose MA, Eickmeier O, Travaci M, Kitz R, Zielen S. Eur Respir J. 2007;30(1):56–61 PURPOSE OF THE STUDY. To evaluate montelukast's ability to inhibit the late-phase airway response after allergen exposure in adults with house dust mite–induced asthma. STUDY POPULATION. Thirty-five adults (19 men, 16 women) aged 18 to 31 with mild, stable asthma and sensitivity to house dust mites were included. METHODS. This study was designed as a randomized, double-blind, single-dose, placebo-controlled, crossover trial. Subjects underwent serum testing for antigen-specific immunoglobulin E (IgE) to house dust mite. Sensitized subjects were then examined for airway infections and underwent spirometry and determination of their fraction of nitric oxide in exhaled air (FeNO). They were then challenged with increasing concentrations of inhaled Dermatophagoides farinae via a nebulizer system. Testing was stopped when the patient's forced expiratory volume in 1 second (FEV1) decreased at least 20% (early airway response [EAR]), they experienced significant clinical symptoms, or they received a cumulative dose of 1270 mg. Patients were then given 1 puff of salbutamol (0.1 mg) and either montelukast (10 mg) or a placebo. FEV1 was measured for the following 8 hours with a decrease of at least 20% demonstrating a late airway response (LAR). Formoterol (12 μg) was then given to treat those patients. Subjects returned at least 2 weeks later and were crossed-over into the other group. RESULTS. Of the 35 subjects in the study, 12 showed no significant EAR on 1 or both study days, 11 showed only an EAR, and 12 demonstrated both an EAR and LAR. This last group was analyzed further. The difference in FEV1 from baseline values 3 to 8 hours after challenge was expressed as the area under the FEV1 time-response curve (FEV1-AUC). The FEV1-AUC of patients on placebo was −2.47 ± 1.32 vs −0.768 ± 1.68 for the patients on montelukast (P &amp;lt; .005). Subjects with a dual response had a significantly higher baseline FeNO than those with no response (56.4 vs 21.0 ppb; P &amp;lt; .05). CONCLUSIONS. Montelukast was able to block the late-phase airway response in subjects who responded dually to the allergen challenge. In addition, patients with a higher baseline FeNO seemed more likely to develop an LAR than those with lower ones. REVIEWER COMMENTS. The results of this study implicate a role for montelukast as an “add-on,” therapeutic option for symptomatic relief after allergen exposure in subjects with mild asthma. It also suggests a rapid onset of action that allows for its usage in such a setting. This study supports existing ones that have demonstrated the effect of montelukast within 2 to 3 hours for up to 24 hours. There was also a “trend toward significance” showing subjects on montelukast with higher FEV1 values than those on placebo. However, this study was limited in its sample size and should be expanded to fully elicit montelukast's role in acute exacerbations. It would also be worthwhile to investigate its effects on subjects with moderate-to-severe asthma in the same setting. Last, this study also alluded to the fact that a patient's baseline FeNO may be a predictor of whether he or she develops an LAR. This should also be explored further in expanded studies and in children.