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Asthma control in children: Body plethysmography in addition to spirometry.
No full textBACKGROUND
There is a lack of agreement among measures of asthma control in children. In Central Europe, body plethysmography is additionally used for asthma monitoring. However, its value is still unclear.
OBJECTIVES
We investigated the possible additional value of body plethysmographic measures (specific resistance, residual volume-total lung capacity ratio [RV/TLC]) compared with spirometric measures forced expiratory volume in 1 second (FEV 1 ), forced vital capacity (FVC), FEV 1 /FVC, forced expiratory flow at 25% to 75% of forced vital capacity (FEF 25-75 ), and fraction of exhaled nitric oxide (FeNO) for assessment of asthma control.
METHODS
One hundred and forty-five asthmatic children aged 5 to 17 were included. All children performed measurements of FeNO, spirometry, and body plethymography. Asthma control was assessed by the asthma control test (c-ACT/ACT) and a doctor's assessment of asthma control.
RESULTS
Investigating single lung function parameters, FEV1 , FEV 1 /FVC, FEF 25-75 and RV/TLC differed between controlled and partly controlled asthma. However, we found no differences between controlled and uncontrolled asthma with regard to single lung function parameters or for any parameter if investigated in a multivariable approach. This was also true if we combined obtained parameters from spirometry (comparing pathologic vs normal spirometry). Investigating the combination of body plethysmography and doctor's assessment of asthma control a significant association was found ( P = 0.02). Furthermore, combined spirometry and body plethysmography showed a significant association with both doctor's assessed asthma control ( P = 0.009) and the c-ACT/ACT ( P = 0.04). The addition of FeNO did not improve the results.
CONCLUSIONS
The combination of body plethysmography and spirometry shows best agreement with asthma control in children compared with spirometry or body plethysmography alone. Further studies are needed to find out whether additional measurements of body plethysmography improve the outcome of children in asthma monitoring
Elevated exhaled leukotriene B-4 in the small airway compartment in children with asthma
No full textBackground: Inflammatory processes in the asthmatic lung involve the large and small airway and alveolar sites. Leukotriene B-4 (LTB4) is an important disease marker, but its role in inflammation of the small airways in asthma has not been established yet. Objective: To distinguish between large and small airway or alveolar LTB4 concentrations in children with asthma using the new technique of fractionated exhaled breath condensate sampling. Methods: Sixty-eight children (9-17 years old, 33 children with asthma and 35 controls) underwent fractional exhaled nitric oxide (FeNO) measurements, lung function testing, and collection of fractionated exhaled breath condensate using a capnograph-based approach. The LTB4 concentrations in the small airway or alveolar and large airway fractions were correlated to disease status, lung function impairment, and clinical parameters. Results: Children with asthma had significantly higher LTB4 concentrations in the small airway or alveolar fraction than controls (5.58 pg/mL; 95% interquartile range [IQR], 2.0-11.77 pg/mL; vs 2.0 pg/mL; 95% IQR, 2.0-6.2 pg/mL; P=.003). No difference was found between the groups in the large airway fraction. Children with obstructive lung function impairment (forced expiratory volume in 1 second z score < -1.65) had increased small airway or alveolar LTB4 concentrations compared with children without impairment (2.0 pg/ mL; 95% IQR, 2.0-9.21 pg/mL; vs 18.32 pg/mL; 95% IQR, 3.7-23.02 pg/mL; P=.04). Children with asthma but without pathologic obstructive lung function still had higher LTB4 concentrations than controls (5.57 pg/mL; 95% IQR, 2.00-10.60 pg/mL; vs 2.00 pg/mL; 95% IQR, 2.00-6.20 pg/mL; P=.01). Conclusion: LTB4 is detectable and elevated in the small airway or alveolar fraction of exhaled breath condensate in pediatric asthma. Because of the possibility of detecting elevated levels in patients without lung function impairment in controlled disease, it may be used as a noninvasive marker of small airways disease; however, future long-term studies are needed. (C) 2015 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved
New international reference values for spirometry: implications for clinical issues using a comparative analysis of a paediatric population
No full textAir pollution during pregnancy and lung development in the child.
No full textAir pollution exposure has increased extensively in recent years and there is considerable evidence that exposure to particulate matter can lead to adverse respiratory outcomes. The health impacts of exposure to air pollution during the prenatal period is especially concerning as it can impair organogenesis and organ development, which can lead to long-term complications. Exposure to air pollution during pregnancy affects respiratory health in different ways. Lung development might be impaired by air pollution indirectly by causing lower birth weight, premature birth or disturbed development of the immune system. Exposure to air pollution during pregnancy has also been linked to decreased lung function in infancy and childhood, increased respiratory symptoms, and the development of childhood asthma. In addition, impaired lung development contributes to infant mortality. The mechanisms of how prenatal air pollution affects the lungs are not fully understood, but likely involve interplay of environmental and epigenetic effects. The current epidemiological evidence on the effect of air pollution during pregnancy on lung function and children's respiratory health is summarized in this review. While evidence for the adverse effects of prenatal air pollution on lung development and health continue to mount, rigorous actions must be taken to reduce air pollution exposure and thus long-term respiratory morbidity and mortality
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Dopplersonographische Normalwerte für Blutflussparameter der Niere bei gesunden Neugeborenen am ersten und dritten Lebenstag: Dopplersonographische Normalwerte für Blutflussparameter der Nierebei gesunden Neugeborenen am ersten und dritten Lebenstag
Full text linkEine Vielzahl von Faktoren können am Lebensanfang eine ausreichende
Perfusion der Niere gefährden und ihre Funktion beeinträchtigen. Umgekehrt
spiegelt eine suffiziente Nierendurchblutung meist auch eine stabile systemische
Hämodynamik des Neugeborenen wieder. Laborwerte sind in diesem Alter wenig
aussagefähig bezüglich der Nierenfunktion. Ziel dieser Studie war die Erstellung
von dopplersonographischen Normalwerten der Blutflussparameter beim
gesunden Neugeborenen am ersten und dritten Lebenstag.
Es wurden Mittelwerte für die systolische, mittlere und diastolische arterielle
Flussgeschwindigkeit in der A. renalis am ersten und dritten Lebenstag beim
gesunden Neugeborenen durch dopplersonographische Messung bestimmt.
Es konnten dopplersonographische Referenzparameter der Durchblutung der
Niere ermittelt werden, die als unkompliziert messbare Parameter in der
neonatologischen Praxis zur Einschätzung systemisch hämodynamischer
Veränderungen sowie funktioneller Störungen der Niere bis zum akuten
Nierenversagen benutzt werden können
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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