Non-invasive tool to assess heart rhythm in Zebrafish embryos

In the last years the zebrafish (Danio rerio) has emerged as model organism for cardiac research, in spite of the morphological differences with the human heart. In consequence of the similarity to humans in the early function, the zebrafish embryo has been suggested as an ideal model i) to study the molecular mechanism of cardiac development, and ii) to identify genes related to congenital cardiac defects in human [1]. The overall similarity of zebrafish embryos and human, in responses to human cardiotoxic drugs, was demonstrated, for example, in drug-induced cardiac arrhythmia [2]. For this reason, several methods have been developed to assess cardiac functions in zebrafish embryos [3,4]. Unfortunately, all these techniques suffer from drawbacks (time consuming, skillful operator are ended to perform the experiments) which limit their applications for large scale studies. The development in digital imaging has recently made analysis of cardiac functions in genetically modified transparent zebrafish embryos easier. This allowed to assess non-invasively heart rate variability in zebrafish embryos from videos of beating heart, but without measuring heartbeat rhythm, an important indicator of the cardiac function (heartbeat regularity is associated with cardiotoxicity in humans [1]), from power spectrum of heart signal. In the present study, we present a simple, non-invasive method that, by video-recording embryo images using confocal microscopy, and integrating image processing and power spectral analysis, allows to measure the heartbeat rhythm in zebrafish embryos heart chambers (atrium, ventricle, bulb) (Figure 1). The reliability of the herein proposed method was verified. Some embryos undergone treatment by tricaine, a cardiac anaesthetizing drug, in consequence of which a decrease of the heart rate is expected: the heartbeat regularity in tricaine- treated embryos determined from power spectral analysis decreased as compared to no-treated embryos. The results demonstrated that our method is able to assess the cardiac physiology, in term of heart rhythm, in zebrafish embryos

Sensitivity of human pluripotent stem cells to insulin precipitation induced by peristaltic pump-based medium circulation: Considerations on process development

Controlled large-scale production of human pluripotent stem cells (hPSCs) is indispensable for their envisioned clinical translation. Aiming at advanced process development in suspension culture, the sensitivity of hPSC media to continuous peristaltic pump-based circulation, a well-established technology extensively used in hydraulically-driven bioreactors, was investigated. Unexpectedly, conditioning of low protein media (i.e. E8 and TeSR-E8) in a peristaltic pump circuit induced severe viability loss of hPSCs cultured as aggregates in suspension. Optical, biochemical, and cytological analyses of the media revealed that the applied circulation mode resulted in the reduction of the growth hormone insulin by precipitation of micro-sized particles. Notably, in contrast to insulin depletion, individual withdrawal of other medium protein components (i.e. bFGF, TGFβ1 or transferrin) provoked minor reduction of hPSC viability, if any. Supplementation of the surfactant glycerol or the use of the insulin analogue Aspart did not overcome the issue of insulin precipitation. In contrast, the presence of bovine or human serum albumin (BSA or HSA, respectively) stabilized insulin rescuing its content, possibly by acting as molecular chaperone-like protein, ultimately supporting hPSC maintenance. This study highlights the potential and the requirement of media optimization for automated hPSC processing and has broad implications on media development and bioreactor-based technologies. © 2017 The Author(s).Horizon 2020/Marie Skłodowska-Curie Individual Fellowship POSEIDONDFG/EXC/REBIRTHDFG/EXC62/3DFG/ZW64/4-1BMBF/13N12606BMBF/13N14086StemBANCCH2020/TECHNOBEATHannover Medical School internal program (HiLF)Joachim Herz Stiftun

European overview of sustainable policies and approaches in COST C25 member countries

The implementation of the principles and methods towards a Sustainable Construction varies across different countries in Europe. In some countries, the sustainability of the construction sector has been effectively taken into consideration over the last years, while in other its implementation is at an initial stage. Many reasons may be pointed out for this situation. Different countries have different understandings of what is entailed in Sustainable Construction. Different cultural and educational backgrounds, along with different priorities in each country, are also contributing for the lack of a common European approach. General frameworks, aiming to cover every aspect of Sustainable Construction and to provide a consistent and integrated approach, such as Agenda 21 for Sustainable Construction, gave a major advance in the search for a common approach for the construction sector. However, general agreed methodologies and tools to make this common approach operational are still missing.European Science Foundation - COST Action C2

Volume Tracking: A new method for quantitative assessment and visualization of intracardiac blood flow from three-dimensional, time-resolved, three-component magnetic resonance velocity mapping

<p>Abstract</p> <p>Background</p> <p>Functional and morphological changes of the heart influence blood flow patterns. Therefore, flow patterns may carry diagnostic and prognostic information. Three-dimensional, time-resolved, three-directional phase contrast cardiovascular magnetic resonance (4D PC-CMR) can image flow patterns with unique detail, and using new flow visualization methods may lead to new insights. The aim of this study is to present and validate a novel visualization method with a quantitative potential for blood flow from 4D PC-CMR, called Volume Tracking, and investigate if Volume Tracking complements particle tracing, the most common visualization method used today.</p> <p>Methods</p> <p>Eight healthy volunteers and one patient with a large apical left ventricular aneurysm underwent 4D PC-CMR flow imaging of the whole heart. Volume Tracking and particle tracing visualizations were compared visually side-by-side in a visualization software package. To validate Volume Tracking, the number of particle traces that agreed with the Volume Tracking visualizations was counted and expressed as a percentage of total released particles in mid-diastole and end-diastole respectively. Two independent observers described blood flow patterns in the left ventricle using Volume Tracking visualizations.</p> <p>Results</p> <p>Volume Tracking was feasible in all eight healthy volunteers and in the patient. Visually, Volume Tracking and particle tracing are complementary methods, showing different aspects of the flow. When validated against particle tracing, on average 90.5% and 87.8% of the particles agreed with the Volume Tracking surface in mid-diastole and end-diastole respectively. Inflow patterns in the left ventricle varied between the subjects, with excellent agreement between observers. The left ventricular inflow pattern in the patient differed from the healthy subjects.</p> <p>Conclusion</p> <p>Volume Tracking is a new visualization method for blood flow measured by 4D PC-CMR. Volume Tracking complements and provides incremental information compared to particle tracing that may lead to a better understanding of blood flow and may improve diagnosis and prognosis of cardiovascular diseases.</p