Symptoms of atopic asthma often disappear at puberty. However, asthmatic subjects in clinical remission will frequently have a relapse later in life. The aim of this study was to investigate whether ...subjects in clinical remission of atopic asthma have persistent airway inflammation and/or airway remodeling. Bronchial biopsies were obtained from subjects in clinical remission, asthmatic subjects, and healthy control subjects. The presence and/or activation state of eosinophils, mast cells, macrophages, T lymphocytes, interleukin (IL)-5, eotaxin, and inducible nitric oxide synthase (iNOS) were analyzed. Results were compared with less invasive indicators of airway inflammation. Also aspects of airway remodeling were determined. Eosinophils, T cells, mast cells, and IL-5 were significantly elevated in the airway mucosa of subjects in remission compared with control subjects. Also, blood eosinophil cell counts were significantly higher in subjects in clinical remission. Blood eosinophil cell counts, exhaled nitric oxide (eNO) levels, and bronchial response to adenosine-5'-monophosphate correlated significantly with the quantity of tissue eosinophils. Significant airway remodeling was found in subjects in clinical remission. Our study has shown ongoing airway inflammation and airway remodeling in adolescents in clinical remission of atopic asthma. Subclinical airway inflammation may well determine the risk of an asthma relapse later in life.
Allergic rhinitis and asthma often coexist and share a genetic background. Pathophysiologic connections between the nose and lungs are still not entirely understood. This study was undertaken to ...compare allergic inflammation and clinical findings in the upper and lower airways after segmental bronchial provocation (SBP) in nonasthmatic allergic rhinitis patients. Eight nonasthmatic, grass pollen-sensitive patients with allergic rhinitis and eight healthy controls were included. Bronchial biopsies and blood samples were taken before (T(0)) and 24 h (T(24)) after SBP. Nasal biopsies were obtained at T(0), 1 h after SBP (T(1)), and T(24). Immunohistochemical staining was performed for eosinophils (BMK13), interleukin (IL)-5, and eotaxin. The number of eosinophils increased in the challenged and unchallenged bronchial mucosa (p < 0.05) and in the blood (p = 0.03) of atopic subjects at T(24). We detected an increase of BMK13-positive and eotaxin-positive cells in the nasal lamina propria and enhanced expression of IL-5 in the nasal epithelium of atopic subjects only at T(24) (p < 0.05). SBP induced nasal and bronchial symptoms as well as reductions in pulmonary and nasal function in the allergic group. No significant changes could be observed in healthy controls. The study shows that SBP in nonasthmatic allergic rhinitis patients results in peripheral blood eosinophilia, and that SBP can induce allergic inflammation in the nose.
Exosomes are small membrane vesicles secreted into the extracellular compartment by exocytosis. Tumor exosomes may be involved in the sampling of antigens to antigen presenting cells or as decoys ...allowing the tumor to escape immune-directed destruction. The proteins present in exosomes secreted by tumor cells have been poorly defined. This study describes the protein composition of mesothelioma cell-derived exosomes in more detail. After electrophoresis of exosome preparations, matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) was used to characterize the protein spots. MHC class I was found to be present together with the heat shock proteins HSC70 and HSP90. In addition, we found annexins and PV-1, proteins involved in membrane transport and function. Cytoskeleton proteins and their associated proteins ezrin, moesin, actinin-4, desmoplakin, and fascin were also detected. Besides the molecular motor kinesin-like protein, many enzymes were detected revealing the cytoplasmic orientation of exosomes. Most interesting was the detection of developmental endothelial locus-1 (DEL-1), which can act as a strong angiogenic factor and can increase the vascular development in the neighborhood of the tumor. In conclusion, mesothelioma cells release exosomes that express a discrete set of proteins involved in antigen presentation, signal transduction, migration, and adhesion. Exosomes may play an important role in the interaction between tumor cells and their environment.
Background: Allergic rhinitis (AR) and asthma are characterized by means of a similar inflammatory process in which eosinophils are important effector cells. The migration of eosinophils from the ...blood into the tissues is dependent on adhesion molecules. Objective: To analyze the aspects of nasobronchial cross-talk, we studied the expression of adhesion molecules in nasal and bronchial mucosa after nasal allergen provocation (NP). Methods: Nine nonasthmatic subjects with seasonal AR and 9 healthy control subjects underwent NP out of season. Bronchial and nasal biopsy specimens were taken before (T0) and 24 hours after NP (T24). Mucosal sections were analyzed for the presence of eosinophils, IL-5, eotaxin, intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), E-selectin, and human endothelium (CD31). Results: At T24, an influx of eosinophils was detected in nasal epithelium (P = .01) and lamina propria (P < .01), as well as in bronchial epithelium (P = .05) and lamina propria (P < .05), of the patients with AR. At T24, increased expression of ICAM-1, as well as increased percentages of ICAM-1+, VCAM-1+, and E-selectin+ vessels, were seen in nasal and bronchial tissue of patients with AR. The number of mucosal eosinophils correlated with the local expression of ICAM-1, E-selectin, and VCAM-1 in patients with AR. Conclusion: This study shows that NP in patients with AR results in generalized airway inflammation through upregulation of adhesion molecules. (J Allergy Clin Immunol 2001;107:469-76.)
Background. High-grade anal intraepithelial neoplasia (AIN) is present in many human immunodeficiency virus (HIV)-positive men who have sex with men. The major etiologic factor is infection with an ...oncogenic human papillomavirus (HPV) genotype. We investigated whether individual components of high-grade AIN are caused by single HPV types. Methods. DNA was isolated from whole-tissue sections of 31 high-grade AIN that were recovered from 21 HIV-positive men who have sex with men. The SPF10 PCR/LiPA25 HPV genotyping system was used for DNA analysis. In whole-tissue sections with multiple HPV types, polymerase chain reaction was repeated in regions of AIN sampled by laser-capture microdissection. The results were compared with HPV types in anal swabs. Results. A single HPV type was observed in 15 (48%) of 31 whole-tissue sections. In an additional 14 whole-tissue sections, 1 HPV type was found in each lesion sample evaluated by laser-capture microdissection. Consequently, in 29 of 31 biopsy specimens (94%), a single HPV type was found in each lesional component studied. Two wholetissue sections contained collision regions, each with 2 HPV types. HPV16 was presumed to be causative in 14 of 31 biopsy specimens (45%). More than half of the anal swabs did not contain all causative HPV types. Conclusions. Individual components of high-grade AIN are caused by single HPV types (the so-called one lesion, one virus concept). HPV 16 is causative in <50% of cases. Anal swabs are not useful for detecting lesion-specific HPV types.
Mast cells and basophils are cells that play an important role in the initiation and control of allergic inflammation in asthma and rhinitis. This study was undertaken to determine the presence and ...dynamics of mast cells and basophils in the nasal and bronchial mucosa of allergic rhinitis patients after segmental bronchial provocation (SBP). Eight nonasthmatic, grass pollen-allergic rhinitis patients and eight healthy controls were included. Bronchial and nasal biopsies, as well as blood samples, were taken before (T(0)) and 24 h (T(24)) after SBP. Immunohistochemical staining was performed for mast cells (tryptase and chymase; phenotypes MC(T), MC(TC), MC(C)) and basophils (BB1). In the bronchial mucosa, the number of BB1(+) cells increased significantly (p < 0.05) in allergic rhinitis patients after SBP. In the nasal mucosa, the numbers of MC(C) and MC(TC) cells decreased significantly, whereas the numbers of BB1(+) cells increased significantly in allergic rhinitis patients after SBP (p < 0.05). In blood, the number of basophils decreased (p < 0.05) and the level of interleukin (IL)-5 increased (p < 0.05) in atopic patients after SBP. No significant changes could be observed in healthy controls. This study shows that SBP in nonasthmatic allergic rhinitis patients reduces numbers of mast cells in the nose as a result of enhanced degranulation. At the same time, there is evidence for an influx of basophils from the blood into the nasal and bronchial mucosae.
Objective To validate the use of the Wells clinical decision rule combined with a point of care D-dimer test to safely exclude pulmonary embolism in primary care.Design Prospective cohort ...study.Setting Primary care across three different regions of the Netherlands (Amsterdam, Maastricht, and Utrecht).Participants 598 adults with suspected pulmonary embolism in primary care.Interventions Doctors scored patients according to the seven variables of the Wells rule and carried out a qualitative point of care D-dimer test. All patients were referred to secondary care and diagnosed according to local protocols. Pulmonary embolism was confirmed or refuted on the basis of a composite reference standard, including spiral computed tomography and three months’ follow-up.Main outcome measures Diagnostic accuracy (sensitivity and specificity), proportion of patients at low risk (efficiency), number of missed patients with pulmonary embolism in low risk category (false negative rate), and the presence of symptomatic venous thromboembolism, based on the composite reference standard, including events during the follow-up period of three months.Results Pulmonary embolism was present in 73 patients (prevalence 12.2%). On the basis of a threshold Wells score of ≤4 and a negative qualitative D-dimer test result, 272 of 598 patients were classified as low risk (efficiency 45.5%). Four cases of pulmonary embolism were observed in these 272 patients (false negative rate 1.5%, 95% confidence interval 0.4% to 3.7%). The sensitivity and specificity of this combined diagnostic approach was 94.5% (86.6% to 98.5%) and 51.0% (46.7% to 55.4%), respectively.Conclusion A Wells score of ≤4 combined with a negative qualitative D-dimer test result can safely and efficiently exclude pulmonary embolism in primary care.
Symptoms of atopic asthma often decrease or even seem to disappear around puberty. The aim of this study was to investigate whether this so-called clinical remission is accompanied by remission of ...airway inflammation, since symptoms relapse in a substantial proportion of subjects later in life. To assess indicators of inflammation and/or structural damage of the airways, exhaled nitric oxide (eNO) and bronchial responsiveness to adenosine-5'-monophosphate (AMP) and methacholine (MCh) were determined in 21 subjects in clinical remission of atopic asthma. Clinical remission was defined as complete absence of symptoms of asthma without the use of any medication in the year preceding the study. Results were compared with those of 21 patients with current asthma and 18 healthy control subjects. We found significantly higher eNO values in the remission group than in healthy controls (geometric mean, 18.9 and 1.0 ppb, respectively; p < 0.001) whereas eNO values of the remission group and those of the subjects with current asthma (geometric mean, 21.9 ppb) were similar (p = 0.09). The responsiveness to both AMP and MCh of subjects in clinical remission was significantly higher as compared with responsiveness of healthy controls, and lower than responsiveness of subjects with current asthma. A significant correlation could be established between eNO and responsiveness to AMP, but not between eNO and responsiveness to MCh. The results of this study are suggestive of persistent airway inflammation during clinical remission of atopic asthma. We speculate that subclinical inflammation is a risk factor for asthma relapse later in life, and that eNO and responsiveness to both AMP and MCh can be used as different, noninvasive indices of the inflammatory process of the airways.
Summary
Genetical genomics studies uncover genome‐wide genetic interactions between genes and their transcriptional regulators. High‐throughput measurement of gene expression in recombinant inbred ...line populations has enabled investigation of the genetic architecture of variation in gene expression. This has the potential to enrich our understanding of the molecular mechanisms affected by and underlying natural variation. Moreover, it contributes to the systems biology of natural variation, as a substantial number of experiments have resulted in a valuable amount of interconnectable phenotypic, molecular and genotypic data. A number of genetical genomics studies have been published for Arabidopsis thaliana, uncovering many expression quantitative trait loci (eQTLs). However, these complex data are not easily accessible to the plant research community, leaving most of the valuable genetic interactions unexplored as cross‐analysis of these studies is a major effort. We address this problem with AraQTL (http://www.bioinformatics.nl/AraQTL/), an easily accessible workbench and database for comparative analysis and meta‐analysis of all published Arabidopsis eQTL datasets. AraQTL provides a workbench for comparing, re‐using and extending upon the results of these experiments. For example, one can easily screen a physical region for specific local eQTLs that could harbour candidate genes for phenotypic QTLs, or detect gene‐by‐environment interactions by comparing eQTLs under different conditions.
Significance Statement
Mapping of heritable gene expression has uncovered many expression quantitative trait loci (eQTLs) underlying the genetic architecture of plant traits, yet most data are not easily accessible. Here we present AraQTL, an easily accessible online repository of eQTL datasets for comparative analysis and meta‐analysis of all published Arabidopsis eQTL datasets.
Pulmonary embolism (PE) often presents with nonspecific symptoms and may be an easily missed diagnosis. When the differential diagnosis includes PE, an empirical list of frequently occurring ...alternative diagnoses could support the GP in diagnostic decision making.
To identify common alternative diagnoses in patients in whom the GP suspected PE but in whom PE could be ruled out. To investigate how the Wells clinical decision rule for PE combined with a point-of-care d-dimer test is associated with these alternative diagnoses.
Secondary analysis of the Amsterdam Maastricht Utrecht Study on thrombo-Embolism (Amuse-2) study, which validated the Wells PE rule combined with point-of-care d-dimer testing in primary care. All 598 patients had been referred to and diagnosed in secondary care. All diagnostic information was retrieved from the GPs' medical records.
In 516 patients without PE, the most frequent alternative diagnoses were nonspecific thoracic pain/dyspnoea (42.6%), pneumonia (13.0%), myalgia (11.8%), asthma/chronic obstructive pulmonary disease (4.8%), panic disorder/hyperventilation (4.1%) and respiratory tract infection (2.3%). Pneumonia occurred almost as frequent as PE. Patients without PE with either a positive Wells rule (>4) or a positive d-dimer test, were more often (odds ratio = 2.1) diagnosed with a clinically relevant disease than patients with a negative Wells rule and negative d-dimer test.
In primary care patients suspected of PE, the most common clinically relevant diagnosis other than PE was pneumonia. A positive Wells rule or a positive d-dimer test are not only positively associated with PE, but also with a high probability of other clinically relevant disease.
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