Publications by authors named "Damen C"

In the Netherlands, one of the main goals of the Ministry of Infrastructure and Water Management is to increase accessibility and, at the same time, to reduce the negative externalities created by transport, such as congestion and greenhouse gas emissions. Within the Ministry, there was a clear need for a national and integrated monitoring instrument to measure the impact of policy measures on travel behaviour. To satisfy this need, we carried out a national traveller survey in 2019, 2020 and 2021.

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Sensor platforms can benefit from the incorporation of polymer brushes since brushes can concentrate the analyte near the sensor surface. Brushes that absorb acetone vapor are of particular interest since acetone is an important marker for biological processes. We present a simple procedure to synthesize acetone-responsive poly(methyl acrylate) brushes.

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Purpose: Increased renal elimination is the leading cause for subtherapeutic concentrations of renally cleared antibiotics and it has been hypothesized that brain damaged patients in the intensive care unit (ICU) are particularly at risk. The objective of this study is to determine the prevalence of subtherapeutic piperacillin concentrations in neurocritical patients and to investigate if having a neurocritical diagnosis is a risk factor for this.

Materials And Methods: Single center retrospective analysis of a prospective cohort study of adult ICU patients receiving continuous infusion piperacillin/tazobactam.

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Background: Videolaryngoscopy (VL) is increasingly used, but not yet routine practice, for tracheal intubation. Few departments formally trial equipment before adopting it into practice. We describe the decision-making and implementation processes that our department used when introducing universal VL, with the C-MAC (Karl Storz, Germany), throughout our anaesthesia and intensive care departments.

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Background: The number of surgical procedures performed in elderly and frail patients has greatly increased in the last decades. However, there is little research in the elderly emergency general surgery patient. The aim of this study was to assess the prevalence of frailty in the emergency general surgery population in Belgium.

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Heterostructures formed by LaSrMnO/ZnO (LSMO/ZnO) interfaces exhibit extremely interesting electronic properties making them promising candidates for novel oxide p-n junctions, with multifunctional features. In this work, the structure of the interface is studied through a combined experimental/theoretical approach. Heterostructures were grown epitaxially and homogeneously on 4″ silicon wafers, characterized by advanced electron microscopy imaging and spectroscopy and simulated by ab initio density functional theory calculations.

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The possible presence of matrix effect is one of the main concerns in liquid chromatography-mass spectrometry (LC-MS)-driven bioanalysis due to its impact on the reliability of the obtained quantitative results. Here we propose an approach to correct for the matrix effect in LC-MS with electrospray ionization using postcolumn infusion of eight internal standards (PCI-IS). We applied this approach to a generic ultraperformance liquid chromatography-time-of-flight (UHPLC-TOF) platform developed for small-molecule profiling with a main focus on drugs.

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An ultraperformance LC (UPLC) method for the separation of different lipid molecular species and lipid isomers using a stationary phase incorporating charged surface hybrid (CSH) technology is described. The resulting enhanced separation possibilities of the method are demonstrated using standards and human plasma extracts. Lipids were extracted from human plasma samples with the Bligh and Dyer method.

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We investigated the interactions of the anticancer drug vinorelbine with drug efflux transporters and cytochrome P450 3A drug-metabolizing enzymes. Vinorelbine was transported by human multidrug-resistance associated protein (MRP) 2, and Mrp2 knockout mice displayed increased vinorelbine plasma exposure after oral administration, suggesting that Mrp2 limits the intestinal uptake of vinorelbine. Using P-glycoprotein (P-gp), Cyp3a-, and P-gp/Cyp3a knockout mice, we found that the absence of P-gp or Cyp3a resulted in increased vinorelbine plasma exposure, both after oral and intravenous administration.

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Radioiodinated monoclonal antibodies have been used for radioimmunotherapeutic and radiodiagnostic purposes. Radioiodination of monoclonal antibodies may lead to deterioration of the immunoreactivity of the monoclonal antibody. Methods for the determination of the immunoreactivity, however, do not provide information about any structural changes of the radioconjugate which may influence the binding properties of the protein to the target antigen.

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Introduction: In developing countries, patients with a Wilms' tumour often present late with a high degree of malnutrition and large tumours. We investigated whether this affects vincristine pharmacokinetics.

Methods: Patients newly diagnosed with Wilms' tumour in Malawi and the UK were included.

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Monoclonal antibodies are typically glycosylated at asparagine residues in the Fc domain, and glycosylation heterogeneity at the Fc sites is well known. This paper presents a method for rapid analysis of glycosylation profile of the therapeutic monoclonal antibody trastuzumab from different production batches using electrospray quadrupole ion-mobility time-of-flight mass spectrometry (ESI-Q-IM-TOF). The global glycosylation profile for each production batch was obtained by a fast LC-MS analysis, and comparisons of the glycoprofiles of trastuzumab from different lots were made based on the deconvoluted intact mass spectra.

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Monoclonal antibodies (mAbs) are an upcoming group of therapeutic compounds used to treat various types of diseases. Currently more than 100 mAbs are in clinical development. To establish the pharmacokinetic (PK) properties of mAbs many (pre-)clinical studies are executed.

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The bioanalysis of vinca-alkaloids has been investigated extensively. High-performance liquid chromatography coupled to ultraviolet, fluorescence or electrochemical detection have been described. During recent years liquid chromatography coupled with mass spectrometry (LC-MS) has become the first choice for the quantitative bioanalysis of the vinca anticancer agents.

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For the bioanalysis of therapeutic monoclonal antibodies in biological matrices, immunoassays--especially enzyme-linked immunosorbent assays (ELISAs)--are the most widely used techniques. Although ELISAs are very sensitive, the obtained sensitivity is not always sufficient. In this study, we have investigated the possibilities of performing a precipitate-enhanced immunoassay (PEIA) with ellipsometric detection for the bioanalysis of the therapeutic monoclonal antibody trastuzumab.

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A sensitive, specific and efficient high-performance liquid chromatography/tandem mass spectrometry assay for the simultaneous determination of vinorelbine and its metabolite 4-O-deacetylvinorelbine in human and mouse plasma is presented. Heated electrospray ionization was applied followed by tandem mass spectrometry. A 50 microL plasma aliquot was protein precipitated with acetonitrile-methanol (1:1, v/v) containing the internal standard vinorelbine-d3 and 20 microL volumes were injected onto the HPLC system.

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For the quantification of therapeutic monoclonal antibodies in biological specimens, enzyme-linked immunosorbent assay (ELISA) is the most widely used technique. ELISA's have some limitations and therefore alternative analytical techniques are being explored. In this study we describe the development of a bioanalytical assay using high-performance liquid chromatography (HPLC) coupled with fluorescence detection for the bioanalysis of the monoclonal antibody trastuzumab.

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Trastuzumab, a humanized monoclonal antibody, is used for the treatment of breast cancer patients who overexpress the HER2 receptor. To optimize therapy, pharmacokinetic studies are necessary. The aim of this study was to develop an enzyme-linked immunosorbent assay (ELISA) for trastuzumab to support these pharmacokinetic studies.

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A sensitive, specific and efficient high-performance liquid chromatography-tandem mass spectrometry assay for the simultaneous determination of vincristine and actinomycin-D in human dried blood spots is presented. Dried blood spots were punched out of a collection paper with a 0.25-in.

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A sensitive, specific and efficient high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) assay for the simultaneous determination of total vincristine and actinomycin-D concentrations in human plasma and an assay for the determination of unbound vincristine are presented. Electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI) and heated electrospray ionization (H-ESI) were tested as ionization interfaces. For reasons of robustness ESI was chosen followed by tandem mass spectrometry (ESI-MS/MS).

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A sensitive, specific and fast high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) assay for the determination of vinorelbine in mouse and human plasma is presented. A 200 microL aliquot was extracted with solid-phase extraction (SPE) using Bond-Elut C(2) cartridges. Dried extracts were reconstituted in 100 microL 1 mM ammonium acetate pH 10.

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The analytical possibilities of quantification of the intact monoclonal antibody trastuzumab by high-performance liquid chromatography coupled with electrospray mass spectrometry (HPLC-ESI-MS) were investigated. To clarify the results obtained by LC-MS, complementary experiments were performed using direct UV-spectrophotometry and high-performance liquid chromatography coupled with ultraviolet detection (HPLC-UV). A polystyrene-divinylbenzene (POROS) column was applied with gradient elution using formic acid 0.

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Monoclonal antibodies (MOABs) are, due to their specificity, increasingly being deployed for therapeutic purposes. MOABs are derived from immunoglobulins and are fully or partially of murine or human origin. They are administered parenterally: mostly intravenously, but subcutaneous or intramuscular administration is also possible, in which case absorption probably occurs through the lymphatic system.

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Recirculation of leukocytes is mediated by the intricately regulated expression of adhesion molecules on both the vessel wall and leukocyte membranes. In the present paper it is demonstrated that tumor angiogenesis factors impair leukocyte rolling and adhesion under flow conditions. Three lines of evidence presented in this paper support this finding; (i) treatment of cultured endothelial cells (EC) with the angiogenic factor basic fibroblast growth factor (bFGF) results in decreased ICAM-1 expression and decreased numbers of adhering leukocytes under flow conditions.

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Objective: Several clinical studies performed with human recombinant interleukin 10 (IL-10) in patients with rheumatoid arthritis (RA) have shown little efficacy. We investigated potentially proinflammatory in vivo effects of IL-10 in humans. We evaluated the upregulation of Fc gamma receptor (Fc gamma R) expression on monocytes/macrophages (and granulocytes) in patients with RA receiving different dosages of IL-10.

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