1,052 research outputs found
Comparison of two methods of processing induced sputum: Selected versus entire sputum - From the authors.
Selected sputum is a better method for analysing induced sputum,
providing more viable cells, more eosinophilis, and higher
concentration of ECP in asthmatics, but in our hands, the entire
sputum method was also effective at distinguishing asthmatics
from healthy subjects
Effects of intradermal injection of atrial natriuretic peptide.
Atrial natriuretic peptide (ANP) causes mast cell degranulation in rats in vivo and in vitro but is bronchodilator in humans. The aim of this study was to investigate the wheal and flare dose-response to intradermal injection of alpha-human ANP in normal humans. Eight normal subjects received five 30 microliters injections containing 1, 10, 39, 78, 117 pmol ANP and one each of normal saline, histamine 675 pmol and substance P 30 pmol. Maximum ANP flare response was greater but not significantly than that to saline at 1.55 +/- 0.6 (mean +/- s.e. mean) compared with 0.42 +/- 0.17 cm2, but much less than to histamine 9.86 +/- 0.97 or to substance P 12.5 +/- 1.2. Maximum ANP wheal response was significantly greater than that to saline at 0.38 +/- 0.08 compared with 0.18 +/- 0.05 cm2 (difference between means 0.20, 95% CI 0.05, 0.35), but much less than to histamine 0.75 +/- 0.06 or to substance P 1.05 +/- 0.08 cm2. No dose-response to ANP was demonstrated, though responses to the highest dose differed significantly from those to the lowest dose studied. We conclude that human cutaneous responses to ANP differ from those of animals and that the skin is less responsive than other tissues in humans
Sputum induction: a method to assess airway inflammation in asthma.
Abstract
In recent studies, sputum cell counts have been used to examine the cell and molecular markers of airway inflammation. In this paper, we describe three different technical methods of analysing sputum samples: the first using smears, the second using cytocentrifugation after selection of a mucous plug, and the third using cytocentrifugation to analyse the entire sputum sample. These last two techniques have been used in a pilot study to compare the differential cell counts in sputum and bronchoalveolar lavage (BAL). The results show a significant correlation between the percentage of the eosinophils in sputum and bronchial sample of the BAL. Previous results on the study of airway inflammation with the analysis of sputum and the preliminary data on the relationship between sputum and BAL confirm the usefulness of this noninvasive technique in the understanding of the pathogenesis of asthma
Anti-leukotriene intervention: is there adequate information for clinical use in asthma?
AbstractVarious mediators of inflammation have been suggested as being important in the pathogenesis of asthma. These include histamine, acetylcholine, bradykinin, adenosine, prostaglandins D2 and F2α, thromboxane A2, leukotrienes, PAF and, more recently, various cytokines. Intervention in the action of these mediators is proposed to offer therapeutic benefit, and recent advances in drug therapy have centred on two main approaches. Specific and potent leukotriene antagonists and inhibitors of leukotriene biosynthesis have emerged, and their effects against allergen challenge, cold-air- and exercise-induced bronchospasm and aspirin-sensitive asthma have been evaluated. A small number of studies have also been conducted in clinical asthma, with both acute and long-term (up to 20 weeks) efficacy studies being reported. A considerable degree of inter-individual variation is seen in the degree of protection afforded by leukotriene intervention. The extent to which inhibiting one set of inflammatory mediators can be expected to attenuate the asthmatic response can be questioned. As yet, there is no way of distinguishing leukotriene-related asthma from other types. It is likely, however, that leukotriene intervention may be useful in some patients with specific forms of the disease; for example, aspirin-sensitive asthma. Leukotriene intervention is unlikely to replace inhaled corticosteroids in the treatment of asthma, and its position in the guidelines for the management of asthma remain unclear thus far
Anti-leukotriene intervention: is there adequate information for clinical use in asthma?
Author Correction:A cattle graph genome incorporating global breed diversity
The original version of this Article omitted from the author list the 12th and 13th authors Dennis Muhanguzi and Wilson Amanyire, who are from the ‘School of Biosecurity, Biotechnology and Laboratory Sciences (SBLS), College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, P.O Box 7062, Kampala, Uganda’. Consequently, the final sentence of the Author Contributions incorrectly read ‘D.W., P.T., E.A.J.C., C.E., E.T.O., E.R.A., A. Tijjani, K.M., A.F., B.R.F., A.Q., U.C. and P.W. provided samples and expertise for the studies’. This has been replaced with ‘D.W., P.T., W.A., D.M., E.A.J.C., C.E., E.T.O., E.R.A., A. Tijjani, K.M., A.F., B.R.F., A.Q., U.C. and P.W. provided samples and expertise for the studies’. This has been corrected in both the PDF and HTML versions of the Article
Comparison of two methods of processing induced sputum: selected versus entire sputum.
Abstract
Sputum analysis is increasingly used to assess airway inflammation in asthma. The analysis of sputum is currently performed with two techniques, i.e., analysis of selected sputum (plugs) and analysis of entire sputum. To investigate the diagnostic value of these two methods, we compared total and differential cell counts and supernatant eosinophil cationic protein (ECP) in selected and entire sputum collected on two occasions in a group of healthy and asthmatic subjects. We induced sputum with hypertonic saline in 18 asthmatics and in eight healthy subjects. On one occasion we analyzed selected sputum, and on another occasion we analyzed entire sputum. In each sample we measured total and differential cell counts and ECP concentration in supernatant. We found a higher percentage of eosinophils (15.3 versus 8.3%; p < 0.01), more viable nonsquamous cells (80.6 versus 71.8%; p < 0.01), and higher levels of ECP (548 versus 105 microg/L; p < 0.001) in selected sputum as compared with entire sputum, whereas the percentage of neutrophils was higher in the entire sputum (42.7 versus 33.3%; p < 0.05). The percentage of eosinophils and ECP concentration were significantly and similarly increased in both selected and entire sputum of asthmatic subjects, i.e., independent of the method of sputum analysis. In conclusion, the selected sputum method may indeed provide more viable cells, more eosinophils, and a higher concentration of ECP. However, both the selected sputum and the entire sputum method have the same diagnostic value in distinguishing asthmatics from healthy subjects
Induced sputum to assess airway inflammation: a study of reproducibility.
Abstract
BACKGROUND: Infiltration of the airways mucosa with activated inflammatory cells appears to be a major factor in the pathogenesis of asthma and other airway diseases. Examination of sputum provides a direct method to investigate airway inflammation non-invasively.
OBJECTIVES: The aim of the present study was to evaluate the reproducibility of cell counts on cytospins and fluid phase (eosinophil cationic protein, ECP) measurements in a selected portion of induced sputum. We aimed to confirm the validity of the tecnique by comparing measurements between stable asthmatics, allergic rhinithis and healthy subjects.
METHODS: Sputum was induced with hypertonic saline (4.5%) twice within one week in 53 stable asthmatics, 16 subjects with seasonal rhinitis (out of the pollen season), and 19 healthy subjects. Reproducibility was examined within sample (two different plugs of the same sample) between sample (two specimens of induced sputum obtained within one week) and between examiners on stable subjects taking into account sample size, number of examinations per patients and Confidence Interval (CI) of the estimates.
RESULTS: We have found that the method is highly reproducible within sample and between examiners for all types of cells and fluid phase measurements of ECP. It is reproducible between sample for eosinophils, macrophages, neutrophils and ECP, but not for lymphocytes and weakly for epithelial cells. Sputum from asthmatics, in comparison with the sputum of healthy subjects and subjects with rhinitis had higher eosinophils (asthmatics: 12.2% +/- 12.9, rhinitis: 0.4 +/- 0.8, normals: 0.4 +/- 0.7 (%) and ECP (asthmatics: 827 +/- 491 microg/L, rhinitis: 127 +/- 82 normals: 157 +/- 203). No significant differences were found between healthy subjects and subjects with rhinitis. Eosinophil counts were inversely correlated with FEV1 (r = -0.37) expressed as percentage of predicted, but not significantly correlated with PC20 methacholine (r = -0.28) or blood eosinophils (r = 0.26).
CONCLUSIONS: The importance of this study is the confirmation, within important statistical guidelines for a study of reproducibility, that the methods examined are reproducible and valid
Three years of Extreme Physiology & Medicine
© 2015 Grocott and Montgomery. This article is distributed under the terms of the Creative Commons Attribution 4.0 Interna‑
tional License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in
any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Com‑
mons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecom‑
mons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated
The role of the sandprawn, Callichirus kraussi, as an ecosystem engineer in a temporarily open/closed Eastern Cape estuary, South Africa
The role of the sandprawn, Callichirus (=Callianassa) kraussi (Stebbing), as an ecosystem engineer was assessed in the lower reach of the temporarily open/closed Kasouga Estuary situated along the Eastern Cape coastline of southern Africa over the period April 2010 to June 2011. The study comprised two distinct components, a field study and a caging experiment. The field study assessed the correlation between sand prawn densities and selected physico-chemical (organic content of the sediment and bioturbation) and biological (microphytobenthic algal concentrations and macrobenthic abundance and biomass) variables in 50 quadrants in the lower reach of the estuary. Densities of the sand prawn within the quadrants ranged from 0 to 156 ind m⁻² (mean = 37 ind m⁻²). There were no significant correlations between the densities of the sandprawn and the estimates of the organic content of the sediment and the abundance and biomass of the macrofauna (P > 0.05 in all cases). Numerical analyses failed to identify any effect of the sandprawn density on the macrofaunal community structure. The rate of bioturbation was, however, strongly correlated to the sand prawn density. Similarly, the microphytobenthic alga concentrations were significantly negatively correlated to the sand prawn densities ((P < 0.05). The absence of any distinct impact of the sandprawn on the macrobenthic community structure appeared to be related to their low densities in the lower reach of the estuary during the study.
To better understand the role of the sandprawn as an ecosystem engineer, a caging experiment was conducted using inclusion and exclusion treatments (n= 5 for each treatment). Densities of the sandprawn in the inclusion treatments (80 ind m⁻²) were in the range of the natural densities within the estuary. The experiment was conducted over a period of 18 weeks in the lower reach of the estuary during summer. The presence of the sandprawn, C kraussi, contributed to a significant decrease in the microphytobenthic algal concentrations and the abundance and biomass of the macrofauna (P < 0.05 in all cases). The decrease in the microphytobenthic algal concentrations in the presence of the sandprawn appeared to be related to the res-suspension of the sediments (bioturbation) generated by the burrowing and feeding activities of the sandprawn. The observed decrease in macrofaunal abundances and biomass in the inclusion treatments appeared to be mediated by both the decreased food availability (mainly the microphytobenthic algae) and the burial of organisms within the sediments. Numerical analysis indicated that the sandprawn did, however, not contribute to a change in the species composition of the macrofauna. Results of the current study indicate that C.kraussi plays an important role in structuring the invertebrate community and energy flow within temporarily/open closed Kasouga Estuary
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