6 results on '"Majoor, Christof J."'
Search Results
2. Targeted exhaled breath analysis for detection of Pseudomonas aeruginosa in cystic fibrosis patients.
- Author
-
Kos R, Brinkman P, Neerincx AH, Paff T, Gerritsen MG, Lammers A, Kraneveld AD, Heijerman HGM, Janssens HM, Davies JC, Majoor CJ, Weersink EJ, Sterk PJ, Haarman EG, Bos LD, and Maitland-van der Zee AH
- Subjects
- Adolescent, Adult, Cross-Sectional Studies, Exhalation, Female, Humans, Longitudinal Studies, Male, Pseudomonas aeruginosa, Young Adult, Breath Tests methods, Cystic Fibrosis microbiology, Pseudomonas Infections diagnosis, Volatile Organic Compounds analysis
- Abstract
Background: Pseudomonas aeruginosa (PA) is an important respiratory pathogen for cystic fibrosis (CF) patients. Routine microbiology surveillance is time-consuming, and is best performed on expectorated sputum. As alternative, volatile organic compounds (VOCs) may be indicative of PA colonisation. In this study, we aimed to identify VOCs associated with PA in literature and perform targeted exhaled breath analysis to recognize PA positive CF patients non-invasively., Methods: This study consisted of 1) a literature review to select VOCs of interest, and 2) a cross-sectional CF study. Definitions used: A) PA positive, PA culture at visit/chronically; B) PA free, no PA culture in ≥12 months. Exhaled VOCs were identified via quadrupole MS. The primary endpoint was the area under the receiver operating characteristics curve (AUROCC) of individual VOCs as well as combined VOCs against PA culture., Results: 241 VOCs were identified in literature, of which 56 were further evaluated, and 13 could be detected in exhaled breath in our cohort. Exhaled breath of 25 pediatric and 28 adult CF patients, PA positive (n=16) and free (n=28) was available. 3/13 VOCs were significantly (p<0.05) different between PA groups in children; none were in adults. Notably, a composite model based on 5 or 1 VOC(s) showed an AUROCC of 0.86 (CI 0.71-1.0) and 0.87 (CI 0.72-1.0) for adults and children, respectively., Conclusions: Targeted VOC analysis appears to discriminate children and adults with and without PA positive cultures with clinically acceptable sensitivity values., Competing Interests: Declaration of Competing Interests AHM and PB are supported by an innovation grant from Vertex Pharmaceuticals B.V. PJS is scientific advisor and has a formally inconsiderable interest in the SME Breathomix AHM reports grants and personal fees from GSK, Boehringer Ingelheim, and AstraZeneca, and grants from Chiesi, outside the submitted work., (Copyright © 2021. Published by Elsevier B.V.)
- Published
- 2022
- Full Text
- View/download PDF
3. Clinical effects of the three CFTR potentiator treatments curcumin, genistein and ivacaftor in patients with the CFTR-S1251N gating mutation.
- Author
-
Berkers G, van der Meer R, van Mourik P, Vonk AM, Kruisselbrink E, Suen SW, Heijerman HG, Majoor CJ, Koppelman GH, Roukema J, Janssens HM, de Rijke YB, Kemper EM, Beekman JM, van der Ent CK, and de Jonge HR
- Subjects
- Adolescent, Adult, Child, Cystic Fibrosis genetics, Female, Humans, Male, Organoids drug effects, Aminophenols pharmacokinetics, Chloride Channel Agonists pharmacokinetics, Curcumin pharmacokinetics, Cystic Fibrosis drug therapy, Cystic Fibrosis Transmembrane Conductance Regulator genetics, Genistein pharmacokinetics, Quinolones pharmacokinetics
- Abstract
Background: The natural food supplements curcumin and genistein, and the drug ivacaftor were found effective as CFTR potentiators in the organoids of individuals carrying a S1251N gating mutation, possibly in a synergistic fashion. Based on these in vitro findings, we evaluated the clinical efficacy of a treatment with curcumin, genistein and ivacaftor, in different combinations., Methods: In three multi-center trials people with CF carrying the S1251N mutation were treated for 8 weeks with curcumin+genistein, ivacaftor and ivacaftor+genistein. We evaluated change in lung function, sweat chloride concentration, CFQ-r, BMI and fecal elastase to determine the clinical effect. We evaluated the pharmacokinetic properties of the compounds by evaluating the concentration in plasma collected after treatment and the effect of the same plasma on the intestinal organoids., Results: A clear clinical effect of treatment with ivacaftor was observed, evidenced by a significant improvement in clinical parameters. In contrast we observed no clear clinical effect of curcumin and/or genistein, except for a small but significant reduction in sweat chloride and airway resistance. Plasma concentrations of the food supplements were low, as was the response of the organoids to this plasma., Conclusions: We observed a clear clinical effect of treatment with ivacaftor, which is in line with the high responsiveness of the intestinal organoids to this drug. No clear clinical effect was observed of the treatment with curcumin and/or genistein, the low plasma concentration of these compounds emphasizes that pharmacokinetic properties of a compound have to be considered when in vitro experiments are performed., Competing Interests: Declaration of Competing Interest J.M.B. and C.K.v.d.E are inventors on a patent application related to these findings. GHK reports research funding from the Lung Foundation of the Netherlands, GSK, Ubbo Emmius Foundation, Vertex, TEVA the Netherlands, TETRI Foundation, outside the submitted work and participation in advisory boards from GSK and PureIMS, outside the submitted work., (Copyright © 2020. Published by Elsevier B.V.)
- Published
- 2020
- Full Text
- View/download PDF
4. Corticosteroid Withdrawal-Induced Loss of Control in Mild to Moderate Asthma Is Independent of Classic Granulocyte Activation.
- Author
-
de Groot LES, van de Pol MA, Fens N, Dierdorp BS, Dekker T, Kulik W, Majoor CJ, Hamann J, Sterk PJ, and Lutter R
- Subjects
- Administration, Inhalation, Adult, Biomarkers analysis, Blood Cell Count, Female, Humans, Male, Oxidative Stress, Prospective Studies, Respiratory Function Tests, Surveys and Questionnaires, Adrenal Cortex Hormones administration & dosage, Asthma drug therapy, Granulocytes drug effects
- Abstract
Background: Loss of asthma control and asthma exacerbations are associated with increased sputum eosinophil counts. However, whether eosinophils, or the also present neutrophils, actively contribute to the accompanying inflammation has not been extensively investigated., Methods: Twenty-three patients with mild to moderate asthma were included in a standardized prospective inhaled corticosteroid (ICS) withdrawal study; 22 of the patients experienced loss of asthma control. The study assessed various immune, inflammatory, and oxidative stress parameters, as well as markers of eosinophil and neutrophil activity, in exhaled breath condensate, plasma, and sputum collected at three phases (baseline, during loss of control, and following recovery)., Results: Loss of asthma control was characterized by increased sputum eosinophils, whereas no differences were detected between the three phases for most inflammatory and oxidative stress responses. There were also no differences detected for markers of activated eosinophils (eosinophil cationic protein and bromotyrosine) and neutrophils (myeloperoxidase and chlorotyrosine). However, free eosinophilic granules and citrullinated histone H
3 , suggestive of eosinophil cytolysis and potentially eosinophil extracellular trap formation, were enhanced. Baseline blood eosinophils and changes in asymmetric dimethylarginine (an inhibitor of nitric oxide synthase) in plasma were found to correlate with the decrease in FEV1 percent predicted upon ICS withdrawal (both, rs = 0.46; P = .03)., Conclusions: The clinical effect in mild to moderate asthma upon interruption of ICS therapy is not related to the classic inflammatory activation of eosinophils and neutrophils. It may, however, reflect another pathway underlying the onset of loss of disease control and asthma exacerbations., Trial Registry: The Netherlands Trial Register; No.: NTR3316; URL: trialregister.nl/trial/3172., (Copyright © 2019 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)- Published
- 2020
- Full Text
- View/download PDF
5. Use of oral glucocorticoids and the risk of pulmonary embolism: a population-based case-control study.
- Author
-
Stuijver DJF, Majoor CJ, van Zaane B, Souverein PC, de Boer A, Dekkers OM, Büller HR, and Gerdes VEA
- Subjects
- Administration, Oral, Adolescent, Adult, Aged, Aged, 80 and over, Arthritis drug therapy, Asthma drug therapy, Case-Control Studies, Dose-Response Relationship, Drug, Female, Glucocorticoids therapeutic use, Humans, Inflammatory Bowel Diseases drug therapy, Male, Middle Aged, Registries, Retrospective Studies, Risk Factors, Young Adult, Glucocorticoids administration & dosage, Glucocorticoids adverse effects, Pulmonary Embolism epidemiology
- Abstract
Background: Recently, endogenous glucocorticoid excess has been identified as a risk factor for VTE. Whether exogenous use of glucocorticoids is associated with an increased risk of VTE is unclear. We aimed to quantify the risk of symptomatic pulmonary embolism (PE) in patients using corticosteroids., Methods: A case-control study using the PHARMO Record Linkage System, a Dutch population-based pharmacy registry, was conducted. Cases were 4,495 patients with a first hospital admission for PE between 1998 and 2008. Control subjects were 16,802 sex- and age-matched subjects without a history of PE. International Classification of Diseases codes for hospitalization were used to retrieve information on underlying conditions., Results: The risk of PE was highest in the first 30 days of glucocorticoid exposure (adjusted OR, 5.9; 95% CI, 2.3-3.9) and gradually decreased with increasing duration of use (OR, 1.9; 95% CI, 1.3-2.9) for long-term users (> 1 year). Low-dose glucocorticoid use (prednisolone daily dose equivalent < 5 mg) carried a twofold increased risk of PE (OR, 1.8; 95% CI, 1.3-2.4), whereas a 10-fold increased risk was observed for the highest dose of glucocorticoids (prednisolone > 30 mg) (OR, 9.6; 95% CI, 4.3-20.5). Stratification for both duration and dose of glucocorticoid showed the highest risk of PE in recently started users compared with long-term users at the time of PE, irrespective of the dose., Conclusion: Patients treated with oral glucocorticoids may be at an increased risk of PE, especially during the first month of exposure. This hypothesis requires confirmation in future studies.
- Published
- 2013
- Full Text
- View/download PDF
6. Asthma and coagulation.
- Author
-
de Boer JD, Majoor CJ, van 't Veer C, Bel EH, and van der Poll T
- Subjects
- Administration, Inhalation, Animals, Anticoagulants administration & dosage, Anticoagulants therapeutic use, Asthma drug therapy, Asthma metabolism, Blood Coagulation physiology, Blood Coagulation Disorders drug therapy, Blood Coagulation Factors metabolism, Blood Platelets metabolism, Fibrinolysis, Heparin administration & dosage, Heparin therapeutic use, Humans, Protein C metabolism, Receptor, PAR-2 metabolism, Signal Transduction, Asthma complications, Blood Coagulation Disorders complications, Blood Coagulation Disorders metabolism
- Abstract
Asthma is a chronic airway disease characterized by paroxysmal airflow obstruction evoked by irritative stimuli on a background of allergic lung inflammation. Currently, there is no cure for asthma, only symptomatic treatment. In recent years, our understanding of the involvement of coagulation and anticoagulant pathways, the fibrinolytic system, and platelets in the pathophysiology of asthma has increased considerably. Asthma is associated with a procoagulant state in the bronchoalveolar space, further aggravated by impaired local activities of the anticoagulant protein C system and fibrinolysis. Protease-activated receptors have been implicated as the molecular link between coagulation and allergic inflammation in asthma. This review summarizes current knowledge of the impact of the disturbed hemostatic balance in the lungs on asthma severity and manifestations and identifies new possible targets for asthma treatment.
- Published
- 2012
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.