Uncovering students' misconceptions by assessment of their written questions.

Background: Misconceptions are ideas that are inconsistent with current scientific views. They are difficult to detect and refractory to change. Misconceptions can negatively influence how new concepts in science are learned, but are rarely measured in biomedical courses.

Challenging students to formulate written questions: a randomized controlled trial to assess learning effects.

Background: Underutilization of dialogue among students during small-group work is a threat to active meaningful learning. To encourage small-group learning, we challenged students to generate written questions during a small-group work session. As gender differences have been shown to affect learning, these were also inventoried.

Neoadjuvant sorafenib treatment of clear cell renal cell carcinoma and release of circulating tumor fragments.

Background: Clear cell renal cell carcinoma (ccRCC) is characterized by high constitutive vascular endothelial growth factor A (VEGF-A) production that induces a specific vascular phenotype. We previously reported that this phenotype may allow shedding of multicellular tumor fragments into the circulation, possibly contributing to the development of metastasis. Disruption of this phenotype through inhibition of VEGF signaling may therefore result in reduced shedding of tumor fragments and improved prognosis.

Explicit feedback to enhance the effect of an interim assessment: a cross-over study on learning effect and gender difference.

In a previous study we demonstrated by a prospective controlled design that an interim assessment during an ongoing small group work (SGW) session resulted in a higher score in the course examination. As this reflects the so-called testing effect, which is supposed to be enhanced by feedback, we investigated whether feedback following an interim assessment would have an effect on the score of the course exam, and whether the effect is influenced by the gender of the student. During a General Pathology bachelor course all 386 (bio) medical students took an interim assessment on the topics cell damage (first week) and tumour pathology (fourth week).

Circulating tumour tissue fragments in patients with pulmonary metastasis of clear cell renal cell carcinoma.

Tumour metastasis is the result of a complex sequence of events, including migration of tumour cells through stroma, proteolytic degradation of stromal and vessel wall elements, intravasation, transport through the circulation, extravasation and outgrowth at compatible sites in the body (the 'seed and soil' hypothesis). However, the high incidence of metastasis from various tumour types in liver and lung may be explained by a stochastic process as well, based on the anatomical relationship of the primary tumour with the circulation and mechanical entrapment of metastatic tumour cells in capillary beds. We previously reported that constitutive VEGF-A expression in tumour xenografts facilitates this type of metastatic seeding by promoting shedding of multicellular tumour tissue fragments, surrounded by vessel wall elements, into the circulation.

Amyloid beta induces cellular relocalization and production of agrin and glypican-1.

The major component of senile plaques and vascular amyloid in Alzheimer's disease (AD) brains is the amyloid beta protein (Abeta). Besides Abeta, several other proteins have been identified in these lesions, in particular heparan sulfate proteoglycans (HSPG). However, it is still unclear, what causes the excessive accumulation of HSPG in AD brains.

Expression pattern of apoptosis-related markers in Huntington's disease.

Inappropriate apoptosis has been implicated in the mechanism of neuronal death in Huntington's disease (HD). In this study, we report the expression of apoptotic markers in HD caudate nucleus (grades 1-4) and compare this with controls without neurological disease. Terminal transferase-mediated biotinylated-UTP nick end-labeling (TUNEL)-positive cells were detected in both control and HD brains.

Creatine protects against 3-nitropropionic acid-induced cell death in murine corticostriatal slice cultures.

In murine corticostriatal slice cultures, we studied the protective effects of the bioenergetic compound creatine on neuronal cell death induced by the mitochondrial toxin 3-nitropropionic acid (3-NP). 3-NP caused a dose-dependent neuronal degeneration accompanied by an increased lactate dehydrogenase (LDH) activity in the cell culture medium. An increased ratio of lactate to pyruvate concentration in the medium suggested that metabolic activity shifted to anaerobic energy metabolism.

Elevated levels of vascular endothelial growth factor in serum of patients with D+ HUS.

The pathogenesis of hemolytic uremic syndrome (D+ HUS) is characterized by endothelial damage of glomeruli and tubules within the kidney. In several other diseases in which glomerular endothelial damage occurs, elevated serum levels of vascular endothelial growth factor (VEGF) have been reported. VEGF is involved in angiogenesis, permeabilization of blood vessel endothelium, and wound repair.

Histological analysis of defective colonic healing as a result of angiostatin treatment.

Antiangiogenic therapy is a highly promising new strategy in the treatment of cancer. One of the first angiogenesis inhibitors described was angiostatin, a 38-kDa internal proteolytically generated fragment of plasminogen. In a previous study we found that angiostatin affected physiological angiogenesis as well as tumor angiogenesis.

3-Nitropropionic acid induces cell death and mitochondrial dysfunction in rat corticostriatal slice cultures.

Exposure of organotypic rat corticostriatal slice cultures to the mitochondrial toxin 3-nitropropionic acid (3-NP) resulted in concentration-dependent loss of cresylviolet-stained cells and increase of lactate dehydrogenase and lactate efflux into the culture medium, indicators for cell death and metabolic activity in the slices, respectively. The involvement of apoptosis in these slices was suggested by using the terminal transferase-mediated biotinylated-UTP nick end-labeling (TUNEL) technique, and immunohistochemistry for the apoptosis-related markers Bax and Bcl-2. In 3-NP-exposed slices, TUNEL-positive cells were observed in both the striatum and the cortex but in different forms: striatal neurons were either diffusely stained or showed nuclear fragmentation, cortical neurons only exhibiting nuclear fragmentation.