Biomedical subjects

P Latzin

Publications and source records attributed to P Latzin.

4 recordsLinked to original sources

PubMed2002

Exhaled hydrogen peroxide, nitrite and nitric oxide in healthy children: decrease of hydrogen peroxide by atmospheric nitric oxide.

Hydrogen peroxide (H2O2) and nitrite (NO2-) in exhaled breath condensate have recently been suggested as non-invasive markers of airway inflammation. The goal of this study was to clarify the role of factors that may potentially influence the measurement of H2O2 and nitrite and to look for possible correlations among these inflammatory markers. H2O2 and nitrite values were assessed fluorometrically in breath condensate of 102 healthy children (age 4-18 years) and a detailed status of atopy (including history, lung function and skin prick test) was taken in all children. To find out the role of atmospheric nitric oxide, eNO and envNO were measured via chemiluminescence in association with the sampling of the breath condensate. Median (interquartile range) H2O2 was 0.51 (0.26 - 0.74) microM and nitrite was 3.3 (2.7 4.1) microM. A significant negative correlation between H2O2 and envNO was observed (r = -0.50; p < 0.0001). ENO was independent of envNO at our envNO range up to 56 ppb. No further correlation was found. The inflammatory markers in exhaled breath condensate H2O2, nitrite and eNO are not interrelated to each other in healthy children. Whereas eNO was not dependent on envNO values, high envNO values must be taken into account when measuring H2O2 in exhaled breath condensate.

Adolescent↗

PubMed2001

A noninvasive method to collect nasally exhaled air condensate in humans of all ages.

BACKGROUND: The analysis of exhaled breath condensate may provide valuable insights into inflammatory and other metabolic processes of the lungs. However, its collection by active exhalation with conventional methods is cumbersome, demands a substantial level of co-operation with high motivation and is very difficult or impossible in children younger than about 4-6 years or in the elderly. A comfortable, noninvasive and efficient method is desirable. DESIGN AND PATIENTS: For collection a high-performance pump connected to a cold trap and nasal prongs were used. The volume of the condensate collected was assessed in 141 children of all ages and five adults. As an example for a low molecular component, H2O2 a marker of oxidative stress, was determined fluorometrically. RESULTS: On average, in healthy children from 4 weeks to 18 years of age, 84.0 (79.4, 87.3) microL min(-1) of nasally exhaled air condensate were collected. The volume obtained was about 45% less in 1-6-year-old children, increased linearly with collection time, and averaged about 20-30% of the exhaled water vapour. The concentration of H2O2 in the healthy children was 0.49 (0.48, 0.61) microM and did not depend on age, the time of the day, family, or personal history of atopy and sex. CONCLUSIONS: The method described is generally applicable, comfortable, noninvasive, safe and efficient and allows the collection of nasally exhaled air condensate for the evaluation of metabolic processes of the lungs.

Adolescent↗

PubMed2000

Asthma severity, recommended changes of inhaled therapy and exhaled nitric oxide in children: a prospective, blinded trial.

Orally exhaled nitric oxide (ENO) correlates with several variables of airway inflammation and might be useful to direct asthma therapy. If this is true, ENO should correlate with disease severity and the therapeutic decisions made. - In 74 children with allergic asthma (age 9.7 years, range 4-16) disease severity was determined by history, clinical symptoms, and lung function and inhaled therapy was adjusted according to the NIH criteria. ENO was also measured, but the patients, their parents and the physicians who made the therapeutic decision were left unaware of the results. 31 healthy children served as controls. ENO was higher in asthmatics than in controls, but did not differ with asthma severity. ENO was weakly correlated with the changes in asthma therapy recommended (r = 0.303, P = 0.009). ENO values above normal (> 13 ppb) had a sensitivity of 0.67 and a specificity of 0.65 to predict a step up in therapy. Due to the non-normal distribution of ENO there was a substantial overlap between the different groups. The lack of correlation with disease severity and the weak prediction of physician recommended inhaled therapy, suggest that ENO may be of some value to guide asthma therapy. Studies using ENO to direct therapy are necessary for a definite answer.

Asthma↗

PubMed1999

Characteristics of flow dependency of nitric oxide in exhaled air in children with cystic fibrosis and asthma.

Nitric oxide (NO) is a free radical produced by the lungs which can easily be measured in exhaled air. NO may serve as a non-invasive marker for airway inflammation in chronic inflammatory diseases like asthma. However in patients with cystic fibrosis (CF) and severe airway involvemen normal or low levels of NO have been reported. To investigate this further we measured NO levels in exhaled air at 5 different flow rates in 14 asthmatics, 15 CF-patients and 13 healthy children. A dependency of exhaled NO on expiratory flow was demonstrated in all three groups. At slow flows lower NO levels in CF-patients and significantly higher levels in asthmatics compared to healthy individuals were found. When the data were fitted to a one compartment model of the lung described by NO(MOUTH) = NO(LUNG) - NO(LUNG) x e(-T/Vex) (T = transfer factor; Vex = expiratory flow), NO(LUNG) was increased in asthmatics (191.9 +/- 53.8 ppb) and low in CF (26.7 +/- 5.7 ppb) compared to healthy individuals (76.9 +/- 50.9 ppb; p(anova) = 0.0213). NO produced in the central compartment of the lung behaved similarly and was distinguished from a peripheral compartment with the two compartment model NO(MOUTH) = NO(central) - (NO(central) - NO(peripher) ) x e(-T/Vex). We conclude that NO in exhaled air is flow dependent and at slow expiratory flows elevated in asthmatics and reduced in CF-patients compared to healthy children. Concentrations extrapolated for the whole lung and for the central airways changed proportionally.

Adolescent↗