Jeroen DeGroot

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INTRODUCTION Our objective was to determine whether markers of bone resorption and formation could serve as markers for the presence of bone marrow lesions (BMLs). METHODS We conducted an analysis of data from the Boston Osteoarthritis of the Knee Study (BOKS). Knee magnetic resonance images were scored for BMLs using a semiquantitative grading scheme. In(More)
We investigated whether plasma and synovial fluid (SF) samples from patients with rheumatoid arthritis (RA) contained extracellular mitochondrial DNA (mtDNA) or the oxidatively damaged DNA adduct 8-hydroxy-2'-deoxyguanosine (8-oxodG). Moreover, we correlated the laboratory findings of the patients with RA with their levels of mtDNA and 8-oxodG. SF and(More)
The bioactivity of matrix metalloproteinases was studied in tissues from colorectal cancer patients by means of both quantitative gelatin zymography and a fluorometric activity assay. Next to paired samples of tumour tissue and distant normal mucosa (n=73), transitional tissue was analysed from a limited (n=33) number of patients. Broad-spectrum matrix(More)
The healthy synovial lining layer consists of a single cell layer that regulates the transport between the joint cavity and the surrounding tissue. It has been suggested that abnormalities such as somatic mutations in the p53 tumor-suppressor gene contribute to synovial hyperplasia and invasion in rheumatoid arthritis (RA). In this study, expression of(More)
We used data from a longitudinal observation study to determine whether markers of cartilage turnover could serve as predictors of cartilage loss on magnetic resonance imaging (MRI). We conducted a study of data from the Boston Osteoarthritis of the Knee Study (BOKS), a completed natural history study of knee osteoarthritis (OA). All subjects in the study(More)
A fast and robust method for lipid profiling utilizing liquid chromatography coupled with mass spectrometry has been demonstrated and validated for the analysis of human plasma. This method allowed quantification and identification of lipids in human plasma using parallel alternating low energy and high energy collision spectral acquisition modes. A total(More)
Organic anion-transporting polypeptide 1B1 (OATP1B1) is an important hepatic uptake transporter, of which the polymorphic variant OATP1B1*15 (Asn130Asp and Val174Ala) has been associated with decreased transport activity. Rosuvastatin is an OATP1B1 substrate and often concomitantly prescribed with oral antidiabetics in the clinic. The aim of this study was(More)
BACKGROUND There is growing interest in soluble biomarkers that could be used on the group level for screening purposes in small proof of principle studies during early drug development. We investigated early changes in serum levels of several candidate biomarkers involved in cartilage and bone metabolism following the initiation of adalimumab as a(More)
Cartilage oligomeric matrix protein (COMP) is a protein present in the cartilage matrix and is expressed more abundantly in osteoarthritis cartilage than in healthy cartilage. The present study was designed to investigate the effect of transforming growth factor β (TGFβ) on COMP deposition and the influence of COMP on collagen biochemistry in a long-term(More)
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