marianne donker - Academia.edu (original) (raw)

Papers by marianne donker

Internet interventions, Feb 1, 2024

JMIR formative research, Nov 9, 2023

BMJ Open Quality

BackgroundAudit and feedback (A&F) is a valuable quality improvement strategy, which can contribu... more BackgroundAudit and feedback (A&F) is a valuable quality improvement strategy, which can contribute to de-implementation of low-value care. In the Netherlands, all health insurers collaboratively provide A&F to general practitioners (GPs), the ‘Primary Care Practice Report’ (PCPR). Unfortunately, the use of this report by GPs is limited. This study examined the thoughts of GPs on the usability of the PCPR and GPs recommendations for improving the PCPR.MethodWe used an interpretative qualitative design, with think-aloud tasks to uncover thoughts of GPs on the usability of the PCPR and semistructured interview questions to ask GPs’ recommendations for improvement of the PCPR. Interviews were audiorecorded and transcribed ad verbatim. Data were analysed using thematic content analysis.ResultsWe identified two main themes: ‘poor usability of the PCPR’, and ‘minimal motivation to change based on the PCPR’. The GPs found the usability of the PCPR poor due to the feedback not being clinica...

Functional Ecology, 1992

Environmental pollution is often accompanied by changes in the energy budgets of organisms living... more Environmental pollution is often accompanied by changes in the energy budgets of organisms living in the polluted area. This study investigated whether metal soil pollution affected energy reserves (protein, glycogen and lipid content) and resistance to starvation in isopods (Porcellio scaber), sampled from a reference, mine and smelter area. Mine isopods were in good physiological condition compared to the reference isopods because energy reserves (lipid, glycogen and protein) in the hepatopancreas were not decreased compared to the reference isopods. In the smelter isopods energy reserves were lower, especially in the largest isopods, which contained the highest zinc, copper and cadmium concentrations

Applied Soil Ecology, 2004

The idea that terrestrial isopods regulate copper intake through the state of their copper stores... more The idea that terrestrial isopods regulate copper intake through the state of their copper stores by selection of an optimal copper diet has never been experimentally assessed. We investigated discrimination between untreated and Cu-enriched diets in the isopod Porcellio scaber in relation to their copper stores. Animals were pre-exposed to untreated or Cu-enriched poplar leaves. After 14 and 28 days of pre-exposure, two-way food choice experiments were performed for 14 days. Food consumption rates and the amount of copper accumulated due to the copper content of the food and the duration of pre-exposure were compared. Food selection and rejection as ways by which P. scaber may reduce or avoid the toxic effects of copper were evaluated. P. scaber offered both Cu-enriched food and untreated food preferred the latter, irrespective of the amount of assimilated copper. Copper body burdens increased with copper concentration in the food. In animals offered both Cu-enriched and untreated food, copper body burden also increased, but to a lower extent than in animals fed only a Cu-enriched diet. Therefore, food selection is a way of regulating copper intake, but only to a limited extent. The mortality of experimental animals increased significantly after longer exposure to highly Cu-enriched food. We conclude that in P. scaber, the possibility of selecting food of different copper content may mitigate but cannot prevent the toxic effects of copper in copper-polluted environments.

BMC Health Services Research

Background Despite the increased deployment and added value of Advanced Practitioner Physiotherap... more Background Despite the increased deployment and added value of Advanced Practitioner Physiotherapy (APP) in musculoskeletal care internationally, APP is not yet widely accepted within Dutch primary care. This may be due to specific constraints in the implementation of APP within the Dutch healthcare system. This study aimed to explore the experiences and perceptions of Advanced Practitioner Physiotherapists (APPs) and General Practitioners (GPs) with respect to implementing APP within Dutch primary care. Methods This explorative and interpretive qualitative study included 12 APPs and 3 GPs who were in various stages of implementing an APP care model. Semi-structured interviews were conducted between January and March 2021. The topic list was based on existing literature, the personal input of researchers, and the Constellation Approach framework. Data were analysed using a thematic inductive approach. Results Four main themes emerged from the data; 1) Both GPs’ trust in APP and a cl...

BMC Health Services Research, 2022

Background Patients having forgone healthcare because of the costs involved has become more preva... more Background Patients having forgone healthcare because of the costs involved has become more prevalent in recent years. Certain patient characteristics, such as income, are known to be associated with a stronger demand-response to cost-sharing. In this study, we first assess the relative importance of patient characteristics with regard to having forgone healthcare due to cost-sharing payments, and then employ qualitative methods in order to understand these findings better. Methods Survey data was collected from a Dutch panel of regular users of healthcare. Logistic regression models and dominance analyses were performed to assess the relative importance of patient characteristics, i.e., personal characteristics, health, educational level, sense of mastery and financial situation. Semi-structured interviews (n = 5) were conducted with those who had forgone healthcare. The verbatim transcribed interviews were thematically analyzed. Results Of the 7,339 respondents who completed the q...

Background The avoidance of healthcare by patients because of the costs involved has become more ... more Background The avoidance of healthcare by patients because of the costs involved has become more prevalent in recent years. Certain patient characteristics, such as income, are known to be associated with a stronger demand-response to cost-sharing. In this study, we first assess the relative importance of patient characteristics with regard to the avoidance of healthcare due to cost-sharing payments, and then employ qualitative methods in order to understand these findings better. Methods Survey data was collected from a Dutch panel of frequent users of healthcare. Logistic regression models and dominance analyses were performed to assess the relative importance of patient characteristics with regard to the avoidance, i.e., personal characteristics, health, skills and financial situation. Semi-structured interviews (n = 5) were conducted with those who had avoided healthcare. The verbatim transcribed interviews were thematically analyzed. Results Of the 7,339 respondents who complet...

Background Audit and feedback informs healthcare providers and may affect professional practice a... more Background Audit and feedback informs healthcare providers and may affect professional practice and patient outcomes. The Primary Care Practice Report (PCPR) is a web based personalized feedback instrument for general practitioners (GPs) in the Netherlands, based on claims data. Its yearly uptake is limited. In order to improve the use and usability of the report this study aims to identify key criteria that GPs deem important for audit and feedback. Methods A qualitative interpretative approach was used. We interviewed 12 GPs about their use of the practice report. These interviews followed the Three-Step Test-Interview method. Thematic content analysis was used to investigate the perception of the GP on the report and their perspective on the usability. The interviews resulted in critical items for audit and feedback, on which all tables and graphs in the report were systematically assessed. Results From the interviews with GPs recurring criteria emerged that were identified as de...

Reviews of environmental contamination and toxicology, 2000

This review has served to present the most recent information on a selected series of biomarker s... more This review has served to present the most recent information on a selected series of biomarker studies undertaken on soil invertebrates during two extensive European-funded scientific consortia, BIOPRINT and BIOPRINT-II. The goals were to develop and validate methods for the analysis of markers of stress in a range of soil-dwelling organisms. We have discussed the potential and limitations of the following invertebrate biomarkers for soil risk assessment purposes: heat shock proteins, histological and ultrastructural markers, metallothioneins and metal-binding proteins, esterases, lysosomal integrity, and the novel biomarker histidine. The hsp response in soil invertebrates is especially suitable to indicate the effects of exposure to comparatively low concentrations for a range of toxicants and can be regarded as a biomarker of general stress. The application of MTs and other metal-binding proteins as biomarkers for exposure in soil invertebrates has been well described, and new m...

Oecologia, 1993

Organisms inhabiting metal-contaminated areas can be stressed by metal exposure and are possibly ... more Organisms inhabiting metal-contaminated areas can be stressed by metal exposure and are possibly subject to selection, resulting in increased metal tolerance and changes in growth and/or reproduction characteristics. In a previous study it was found that in the terrestrial isopod Porcellio scaber, sampled from the vicinity of a zinc smelter, the body size was small and the brood size was large compared to isopods from a reference area. To assess whether these differences were due to genetic differentiation between strains, isopods collected from a reference wood, a zinc smelter area and a lead mine were cultured on non-polluted food, while growth, reproduction and metal concentrations were studied in first and second laboratory generations. The isopods from the three populations differed in age and weight at first reproduction, although there were hardly any differences in growth. The females of the mine and the smelter population started to reproduce earlier, at a lower weight, which resulted in fewer young per female. However, reproductive allocation (= weight of young relative to the weight of the mother) was higher in mine and smelter isopods. We conclude that the isopods at the metal-contaminated sites have been selected for early reproduction and increased reproductive allocation. The results indicate that populations inhabiting metal-polluted sites have probably undergone evolutionary changes. This study showed that growth and reproduction characteristics of different populations under laboratory conditions may provide information on selection processes in the field.

Insect Biochemistry and Molecular Biology, 2001

Metallothionein (MT) is an ubiquitous heavy metal-binding protein which has been identified in an... more Metallothionein (MT) is an ubiquitous heavy metal-binding protein which has been identified in animals, plants, protists, fungi and bacteria. In insects, primary structures of MTs are known only for Drosophila and the collembolan, Orchesella cincta. The MT cDNA from O. cincta encodes a 77 amino acid protein with 19 cysteines. Isolations of the protein itself have demonstrated the presence of two smaller metal-binding peptides, whose amino acid sequences correspond to parts of the cDNA, and which apparently result from cleavage of the native protein. The present study was undertaken to complete the picture of cleavage sites within the MT protein by applying protein isolation techniques in combination with mass spectrometry and N-terminal sequence analysis. Further, recombinant expression allowed us to study the intrinsic stability of the MT and to perform in vitro cleavage studies. The results show that the MT from O. cincta is specifically cleaved at two sites, both after the amino acid sequence Thr-Gln (TQ). One of these sites is located in the N-terminal region and the other in the linker region between two putative metalbinding clusters. When expressed in Escherichia coli, the recombinant O. cincta MT can be isolated in an uncleaved form; however, this protein can be cleaved in vitro by the proteolytic activity of O. cincta. In combination with other studies, the results suggest that the length of the linker region is important for the stability of MT as a two domain metal-binding protein.

Health Promotion Practice, 2012

Background. Intervention fidelity is an increasingly important methodological concept in process ... more Background. Intervention fidelity is an increasingly important methodological concept in process evaluations. In this article, the authors investigated the intervention fidelity in a randomized controlled trial on excessive weight gain prevention in pregnancy. Method. A sample of 109 audiotaped counseling sessions, linked to 65 women in the intervention group of the New Life(style) trial, was drawn. The following criteria were quantitatively evaluated using a fidelity checklist: (a) reach, (b) dose, (c) adherence to study objectives, (d) adherence to underlying problem-solving treatment (PST) theory, and (e) counselor competence. Results. A total of 60.4% received all counseling sessions. The dose of intervention components was generally moderate (50.9% to 60.4%), and the dose of PST components was low (17.3%). Adherence to study objectives was moderate (64.2%) and adherence to PST theory was low (43.2%). The counselors sufficiently stimulated the participant to optimize lifestyle (...

Functional Ecology, 1998

1. Temperature has an important effect on all physiological processes in animals that rely on ext... more 1. Temperature has an important effect on all physiological processes in animals that rely on external sources of heat (ectotherms). In an attempt to elucidate the interaction between temperature and the response of ectotherms to heavy metals, a study was made of growth (increase of body mass) of the isopod Porcellio scaber under four constant temperature regimes (12, 16, 20, 24°C), and four different exposures to cadmium (0•016, 0•071, 0•14 and 0•31 µmol g-1 in the diet), in a factorial experiment. 2. There were significant effects on growth rate for both cadmium and temperature, and the interaction between cadmium and temperature was also significant. The average growth rate per week increased with increasing temperature, but the results showed that when cadmium was present at concentrations higher than 0•071 µmol g-1 , it disturbed the temperature-induced growth enhancement. 3. There was a tendency for cadmium to be least toxic at intermediate temperature (16°C), but the 50% and 10% effect concentrations in the diet, estimated by loglogistic curve fitting, did not significantly vary with temperature. The average values were EC 50 = 0•330 µmol g-1 and EC 10 = 0•041 µmol g-1. 4. The Arrhenius model was used to describe the temperature-growth rate relationship, and activation energies were estimated for each cadmium exposure. At the highest cadmium concentration the Arrhenius model did not describe the data very well. The lowest activation energy was observed at 0•14 µmol g-1. 5. Cadmium accumulation in isopods was linearly related to the cadmium concentration in food, for all temperature levels. The significant increase in cadmium concentration with temperature indicates that the effect of temperature on cadmium accumulation is stronger than its effect on body growth. As a whole the data illustrate the importance of taking temperature into account when conducting ecotoxicological studies with soil invertebrates.

Environmental Pollution, 2005

It is often argued that the concentration of a pollutant inside an organism is a good indicator o... more It is often argued that the concentration of a pollutant inside an organism is a good indicator of its bioavailability, however, we show that the rate of uptake, not the concentration itself, is the superior predictor. In a study on zinc accumulation and toxicity to isopods (Porcellio scaber) the dietary EC 50 for the effect on body growth was rather constant and reproducible, while the internal EC 50 varied depending on the accumulation history of the animals. From the data a critical value for zinc accumulation in P. scaber was estimated as 53 mg/g/wk. We review toxicokinetic models applicable to time-series measurements of concentrations in invertebrates. The initial slope of the uptake curve is proposed as an indicator of bioavailability. To apply the dynamic concept of bioavailability in risk assessment, a set of representative organisms should be chosen and standardized protocols developed for exposure assays by which suspect soils can be evaluated.

Background: Despite the increasing deployment and added value of Advanced Practitioner in Physiot... more Background: Despite the increasing deployment and added value of Advanced Practitioner in Physiotherapy (APP) in musculoskeletal care internationally, APP is not widely accepted in Dutch primary care yet. This may be due to constraints in the implementation of APP within the Dutch health care system. The aim of this study was to explore experiences and perceptions of APP and General Practitioners (GP) in implementing APP in Dutch primary care. Methods: This was an explorative and interpretive qualitative study among 13 APPs and 3 GPs that were in various stages of implementing an APP care model. Semi-structured interviews were conducted from January to March 2021. The topic list was based on existing literature, personal input of researchers, and the Constellation Approach framework. Data were analysed using a thematic inductive approach.Results: Four main themes emerged from the data; 1) The start-up of an APP practice requires trust and clear added value for the GP, 2) Starting AP...

Comparative Biochemistry and Physiology Part C: Comparative Pharmacology, 1990

l. In order to evaluate the role of metal-binding proteins in the tolerance mechanism of Porcelli... more l. In order to evaluate the role of metal-binding proteins in the tolerance mechanism of Porcellio saber to heavy metals, a comparative study was made using isopods from three locations: a zinc-lead mine (Plombitres), a zinc smelter (Budel) and a reference wood (Spanderswoud). The Cu, Zn and Cd concentrations and the protein composition were determined in the haemolymph and hepatopancress from the isopods.

Comparative Biochemistry and Physiology Part C: Pharmacology, Toxicology and Endocrinology, 2000

Metallothionein is considered to be a potential biomarker for heavy metal exposure in the terrest... more Metallothionein is considered to be a potential biomarker for heavy metal exposure in the terrestrial environment. However, limited information is available on metallothioneins from insects, a major class of terrestrial invertebrates. In this study we have quantified metallothioneins in the springtail Orchesella cincta by determining metallothionein-bound cadmium after separation of these proteins using gel filtration and reversed phase chromatography from total body homogenates of animals dietary exposed to different concentrations of cadmium. Furthermore, we have studied in more detail where cadmium and metallothionein-bound cadmium is located within this animal. The concentration of metallothionein-bound cadmium increases with the exposure concentration in the same way as the total internal concentration. Both reach a plateau at an exposure concentration of approximately 1.0 mmol Cd/dry food. Cadmium is primarily located within the gut of O. cincta and isolation of metallothionein from this organ gives results identical to isolations from total bodies. Based on this results an estimation of the metallothionein level at the highest exposure concentration results in a concentration of about 115 mg metallothionein/g fresh gut. The O. cincta metallothionein gives the possibility of using this protein as a biomarker for heavy metal exposure in soil insects.