Vascular disrupting action of electroporation and electrochemotherapy with bleomycin in murine sarcoma

Electrochemotherapy has a direct cytotoxic effect on tumour cells, and presumably, a vascular disrupting effect. In this study, on the basis of the prediction of the mathematical model, histological evaluation and physiological measurements of the tumours were carried out to confirm that electroporation and electrochemotherapy of tumours have a vascular disrupting action. In the study, SA-1 solid subcutaneous sarcoma tumours in A/J mice were treated by bleomycin (BLM) given intravenously (1 mg kg−1), application of electric pulses (8 pulses, 1040 V, 100 μs, 1 Hz) or a combination of both – electrochemotherapy. The vascular effect was determined by laser Doppler flowmetry, power Doppler ultrasonographic imaging and Patent blue staining. The extent of tumour hypoxia was determined immunohistochemically by hypoxia marker pimonidazole and partial pressure of oxygen (pO2) in tumours by electron paramagnetic resonance oximetry. Electrochemotherapy with BLM induced good antitumour effect with 22 days, tumour growth delay and 38% tumour cures. The application of electric pulses to the tumours induced instant but transient tumour blood flow reduction (for 70%) that was recovered in 24 h. During this tumour blood flow reduction, we determined an increase in hypoxic tumour area for up to 30%, which was also reflected in reduced tumour oxygenation (for 70%). According to the described mathematical model, endothelial cells lining in tumour blood vessels are exposed to a ∼40% higher electric field than the surrounding tumour cells, and therefore easily electroporated, allowing access of high BLM concentration to the cytosol. Consequently, electrochemotherapy has, besides the immediate vascular disrupting action, also a delayed one (after 24 h), as a consequence of endothelial cell swelling and apoptosis demonstrated by extensive tumour necrosis, tumour hypoxia, prolonged reduction of tumour blood flow and significant tumour growth delay, and tumour cures. Our results demonstrate that in addition to the well-established direct cytotoxic effect on tumour cells, electrochemotherapy also has an indirect vascular disrupting action resulting altogether in extensive tumour cell necrosis leading to complete regression of tumours

Workplace-based assessment: effects of rater expertise

Traditional psychometric approaches towards assessment tend to focus exclusively on quantitative properties of assessment outcomes. This may limit more meaningful educational approaches towards workplace-based assessment (WBA). Cognition-based models of WBA argue that assessment outcomes are determined by cognitive processes by raters which are very similar to reasoning, judgment and decision making in professional domains such as medicine. The present study explores cognitive processes that underlie judgment and decision making by raters when observing performance in the clinical workplace. It specifically focuses on how differences in rating experience influence information processing by raters. Verbal protocol analysis was used to investigate how experienced and non-experienced raters select and use observational data to arrive at judgments and decisions about trainees’ performance in the clinical workplace. Differences between experienced and non-experienced raters were assessed with respect to time spent on information analysis and representation of trainee performance; performance scores; and information processing––using qualitative-based quantitative analysis of verbal data. Results showed expert-novice differences in time needed for representation of trainee performance, depending on complexity of the rating task. Experts paid more attention to situation-specific cues in the assessment context and they generated (significantly) more interpretations and fewer literal descriptions of observed behaviors. There were no significant differences in rating scores. Overall, our findings seemed to be consistent with other findings on expertise research, supporting theories underlying cognition-based models of assessment in the clinical workplace. Implications for WBA are discussed

Proposal for Generic Biomedical Engineering Programs based on European Experience

One of the major objectives of the TEMPUS IV CRH-BME Joint Project is to propose an updated vision of study programs and curricula in the field of biomedical engineering (BME) in Europe. The project emerged as a response to ever increasing and changing demands of the health care sector and industry for education of flexible and competent biomedical engineers on one side and rapidly emerging new technologies and interdisciplinary application domains for BME on the other side. The proposition for curricula reformation and harmonisation presented in this paper is based on identification of five types of BME programs covering 1 st and 2 nd cycle education and on definition of seven core BME topics. The adoption of the proposed structure of generic BME study programs and of the generic BME curriculum will contribute to harmonisation of BME studies and to increased student and teaching staff exchange across Europe, thus promoting the creation of the European Higher Education Area

Promoting harmonization of BME education in Europe: the CRH-BME Tempus project.

Biomedical Engineers should be prepared to adapt to existing or forecasted needs. There is a strong pressure on education, training and life long learning programs to continuously adapt their objectives in order to face new requirements and challenges. The main objective of the TEMPUS IV, CRH-BME project is to update existing curricula in the field of Biomedical Engineering (BME) in order to meet recent and future developments in the area, address new emerging inter-disciplinary domains that appear as a result of the R&D progress and respond to the BME job market demands. The first step is to extensively review the curricula in the BME education field. In this paper, a proposal for a generic curriculum in the BME education is presented, in order to meet recent and future developments and respond to the demands of the BME job market. Adoption of the core program structure will facilitate harmonization of studies as well as student and staff exchange across Europe, thus promoting the European Higher Education Area