De beroepsvoorbereiding van studenten geneeskunde:verkenningen op het gebied van chronisch zieken

The subject of this thesis is the preparation of students for the practice of medicine by undergraduate medical education. The studies presented in this thesis analysed and investigated professional training with attention focused on a particular patient group, the chronically ill

Learning the ropes:strategies program directors use to facilitate organizational socialization of newcomer residents, a qualitative study

Background: Many residents experience their transitions, such as from medical student to resident, as demanding and stressful. The challenges they face are twofold: coping with changes in tasks or responsibilities and performing (new) social roles. This process of 'learning the ropes' is known as Organizational Socialization (OS). Although there is substantial literature on transitions from the perspective of residents, the voices of program directors (PDs) who facilitate and guide residents through the organizational socialization process have not yet been explored. PDs' perspectives are important, since PDs are formally responsible for Postgraduate Medical Education (PGME) and contribute, directly or indirectly, to residents' socialization process. Using the lens of OS, we explored what strategies PDs use to facilitate organizational socialization of newcomer residents. Methods: We conducted semi-structured interviews with 17 PDs of different specialties. We used a theory-informing inductive data analysis study design, comprising an inductive thematic analysis, a deductive interpretation of the results through the lens of OS and, subsequently, an inductive analysis to identify overarching insights. Results: We identified six strategies PDs used to facilitate organizational socialization of newcomer residents and uncovered two overarching insights. First, PDs varied in the extent to which they planned their guidance. Some PDs planned socialization as an explicit learning objective and assigned residents' tasks and responsibilities accordingly, making it an intended program outcome. However, socialization was also facilitated by social interactions in the workplace, making it an unintended program outcome. Second, PDs varied in the extent to which they adapted their strategies to the newcomer residents. Some PDs used individualized strategies tailored to individual residents' needs and skills, particularly in cases of poor performance, by broaching and discussing the issue or adjusting tasks and responsibilities. However, PDs also used workplace strategies requiring residents to adjust to the workplace without much intervention, which was often viewed as an implicit expectation. Conclusions: PDs' used both intentional and unintentional strategies to facilitate socialization in residents, which may imply that socialization can occur irrespective of the PD's strategy. PDs' strategies varied from an individual-centered to a workplace-centered approach to socialization. Further research is needed to gain a deeper understanding of residents' perceptions of PD's efforts to facilitate their socialization process during transitions

Evidence for coordinated regulation of osteoblast function by 1,25-dihydroxyvitamin D3 and parathyroid hormone

AbstractFrom several animal studies and clinical observations it became evident that at target tissue level 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) and parathyroid hormone (PTH) must act in an interrelated manner. In the present study we examined the interaction between 1,25-(OH)2D3 and PTH in the target cell of these hormones in bone, the osteoblast. In addition we studied the role of PTH-activated signal pathways. The three osteoblastic cell lines UMR 106, ROS 172.8 and MG-63 were used as model systems. In UMR 106 cells 1,25-(OH)2D3 and PTH caused a synergistic up-regulation of the vitamin D receptor (VDR) which was accompanied by a synergistic induction of VDR mRNA expression whereas in both ROS 172.8 and MG-63 cells no interaction was observed. In UMR 106 cells the effect of PTH on homologous up-regulation of VDR could be mimicked by the cAMP agonist forskolin and by dibutyrylic-CAMP. Phorbol ester activation of protein kinase C reduced basal as well as 1,25-(OH)2D3-induced up-regulation of VDR. 1,25-(OH)2D3 induced 24-hydroxylase activity in UMR 106 and MG 63 cells and, in contrast to VDR regulation, in both cell lines PTH and 1,25-(OH)2D3 synergistically induce 24-hydroxylase activity. Similar to VDR regulation the effect of PTH was mimicked by activation of cAMP production whereas protein kinase C activation reduced the induction by 1,25-(OH)2D3 Finally, we examined the interaction with respect to osteocalcin synthesis. In ROS 172.8 and MG-63 cells 1,25-(OH)2D3 stimulated osteocalcin production. In ROS 172.8 cells PTH as well as stimulation of cAMP production by forskolin enhanced 1,25-(OH)2D3-induced osteocalcin production whereas, as we have shown previously, activation of protein kinase C does not change 1,25-(OH)2D3- stimulated osteocalcin production. In MG-63 cells neither PTH nor forskolin significantly changed 1,25-(OH)2D3 induction of osteocalcin synthesis. From the present study it can be concluded that indeed at target cell level 1,25-(OH)2D3 and PTH act in a coordinated manner. On basis of the potentiation of 1,25-(OH)2D3 action by PTH in osteoblasts together with the previously reported inhibition of PTH-stimulated cAMP production by 1,25-(OH)2D3 we postulate a negative feedback-loop at target cell level. The activation of the cAMP pathway results in an enhancement of the 1,25-(OH)2D3 action whereas the protein kinase C pathway attenuates the 1,25-(OH)2D3 action. Finally, the present study provides a basis for the indications from in vivo observations about an interrelated action of 1,25-(OH)2D3 and PTH at the target cell. More generally it demonstrates on the basis of analyses of endogenous cellular responses evidence for an interplay between receptor-activated pathways of peptide and steroid hormones

Vitamin D: A modulator of cell proliferation and differentiation

Abstract 1,25-Dihydroxyvitamin D3, [1,25(OH)2D3], the biologically most active metabolite of vitamin D3, is involved in the regulation of calcium homeostasis and bone metabolism. Recently, receptors for 1,25(OH)2D3 have also been shown in cells and tissues not directly related to calcium homeostasis. Experimental data obtained with leukemic and cancer cell lines, both in vitro and in vivo, showed the effects of 1,25(OH)2D3 on cell differentiation and proliferation. However, high doses of the sterol have to be used to observe these effects. Additional studies are needed to establish whether 1,25(OH)2D3 or suitable analogues have a therapeutic potential in malignant diseases without unacceptable toxicity like the development of hypercalcemia

How educational innovations and attention to competencies in postgraduate medical education relate to preparedness for practice:The key role of the learning environment

Introduction Many training programmes in postgraduate medical education (PGME) have introduced competency frameworks, but the effects of this change on preparedness for practice are unknown. Therefore, we explored how elements of competency-based programmes in PGME (educational innovations, attention to competencies and learning environment) were related to perceived preparedness for practice among new consultants. Methods A questionnaire was distributed among 330 new consultants. Respondents rated how well their PGME training programme prepared them for practice, the extent to which educational innovations (portfolio, Mini-CEX) were implemented, and how much attention was paid to CanMEDS competencies during feedback and coaching, and they answered questions on the learning environment and general self-efficacy. Multiple regression and mediation analyses were used to analyze data. Results The response rate was 43 % (143/330). Controlling for self-efficacy and gender, the learning environment was the strongest predictor of preparedness for practice (B = 0.42, p < 0.001), followed by attention to competencies (B = 0.29, p < 0.01). Educational innovations were not directly related to preparedness for practice. The overall model explained 52 % of the variance in preparedness for practice. Attention to competencies mediated the relationship between educational innovations and preparedness for practice. This mediation became stronger at higher learning environment values. Conclusions The learning environment plays a key role in determining the degree to which competency-based PGME prepares trainees for independent practice

Modulation by epidermal growth factor of the basal 1,25(OH)2D3 receptor level and the heterologous up-regulation of the 1,25(OH)2D3 receptor in clonal osteoblast-like cells

The effects of epidermal growth factor (EGF) on basal 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) receptor level and on parathyroid hormone (PTH)-induced 1,25-(OH)2D3 (OH)2D3 receptor up-regulation were studied in the phenotypically osteoblastic cell line UMR 106. EGF in concentrations exceeding 0.1 ng/ml reduced the number of 1,25(OH)2D3 binding sites without changing the binding affinity. Maximal reduction was 30% at about 1 ng/ml. This reduction was independent of a change in cAMP content. EGF dose-dependently attenuated both PTH-induced 1,25(OH)2D3 receptor up-regulation and PTH-stimulated cAMP production without and effect on the ED50 of the PTH effects. For both PTH responses the IC50 and the maximal effective dose were similar, 0.1 ng/ml an 1 ng/ml EGF, respectively. Reduction was first seen at 0.01 ng/ml EGF. At this concentration. EGF reduced PTH-stimulated 1,25-(OH)2D3 receptor binding without an inhibition of the cAMP response. Time-course studies with 1 ng/ml EGF revealed that at 2 h preincubation EGF reduced the heterologous up regulation by PTH, and maximal inhibition was seen after 4 h. In contrast, PTH-stimulated cAMP production was just significantly inhibited only after 6 h, with 60% inhibition after 24 h preincubation. The effects of prostaglandin E2 and forskolin on both 1,25(OH)2D3 binding and cAMP production were inhibited in a similar fashion. On the other hand, dibutyryl cAMP- and 3-isobutyl-1-methylxanthinestimulated 1,25(OH)2D3 binding were not affected by EGF. Taken together, our results demonstrate that EGF reduces both the basal number of 1,25(OH)2D3 binding sites and the heterologous up-regulation of the 1,25(OH)2D3 receptor. The current data suggest that EGF reduces heterologous upregulation of the 1,25(OH)2D3 receptor independent of as well as dependent on the cAMP messenger system. The EGF effect is not primarily located at the PTH receptor, at cAMP phosphodiesterase, or at protein kinase A level