Expression of plasma prekallikrein mRNA in human nonhepatic tissues and cell lineages suggests special local functions of the enzyme

At present it is generally accepted that plasma prekallikrein (PPK) is synthesized in the liver and secreted into the bloodstream. Surprisingly, it has recently been shown that PPK mRNA is present also in RNA from the kidney, adrenal gland and placenta. In spite of its novelty and possible important physiological implications this finding has been neglected. Here we report that PPK mRNA is expressed also in the human brain, heart, lung, trachea, endothelial cells and leukocytes as well as in a variety of fibroblast and epithelial cell lines. Expression of PPK mRNA in fibroblasts, endothelial cells and leukocytes suggests that PPK mRNA detected in RNA preparations from whole tissue may originate solely from these ubiquitously occurring cells. However, PPK mRNA expression in various epithelial cell lines demonstrates that tissue-specific cells also transcribe the PPK gene. The presence of PPK mRNA in nonhepatic tissues and cells indicates that they have the capacity to synthesize the protein. The physiological role of PPK synthesized in extrahepatic tissue is unknown. It may participate in local actions within tissues as well as contributing to the PPK pool in blood plasma. Cultured cells will provide a valuable model for exploring the physiological significance of extrahepatic PPK expression

Accurate and precise quantification of Cu,Zn-SOD in human red blood cells using species-specific double and triple IDMS

Acknowledgements This research was undertaken within the EMRP project HLT05. The EMRP was jointly funded by the EMRP participating countries within EURAMET and the European Union. We gratefully acknowledge support by the Braunschweig International Graduate School of Metrology B-IGSM.Peer reviewedPostprin

Flowcytometric assessment of fetomaternal hemorrhage during external cephalic version at term

External cephalic version (ECV) at term is a safe procedure and reduces the incidence of cesarean sections for breech presentation. One of the known complications, however, is an ECV-related disruption of the placental barrier and a subsequent transfusion of fetal blood into maternal circulation. While the incidence of ECV-related fetomaternal hemorrhage (FMH) has been determined recently in a large trial using a manual Kleihauer-Betke test (KBT), questions remain on the amount of ECV-related FMH. KBT, which detects fetal red blood cells (RBC) on the basis of acidic resistance of fetal hemoglobin (HbF), is known to be a sensitive test, yet prone to procedural errors limiting its accuracy in quantifying FMH. In this study we investigated 50 patients for FMH before and after ECV, using a dual-color flow cytometric test kit with a lower limit of quantification of 0.05% fetal RBC in maternal peripheral blood. Three patients had a quantifiable increase of fetal RBC detected after ECV (0.06%; 0.08%; 0.1%). None of these subtle increments was predictable by ECV-related clinical parameters or translated into fetal compromise. Using a sensitive and accurate flow cytometric test method, our data provide further assurance to mothers on the safety of ECV at term

Bacterial Delivery of RNAi Effectors: Transkingdom RNAi

RNA interference (RNAi) represents a high effective mechanism for specific inhibition of mRNA expression. Besides its potential as a powerful laboratory tool, the RNAi pathway appears to be promising for therapeutic utilization. For development of RNA interference (RNAi)-based therapies, delivery of RNAi-mediating agents to target cells is one of the major obstacles. A novel strategy to overcome this hurdle is transkingdom RNAi (tkRNAi). This technology uses non-pathogenic bacteria, e.g. Escherichia coli, to produce and deliver therapeutic short hairpin RNA (shRNA) into target cells to induce RNAi. A first-generation tkRNAi-mediating vector, TRIP, contains the bacteriophage T7 promoter for expression regulation of a therapeutic shRNA of interest. Furthermore, TRIP has the Inv locus from Yersinia pseudotuberculosis that encodes invasin, which permits natural noninvasive bacteria to enter β1-integrin-positive mammalian cells and the HlyA gene from Listeria monocytogenes, which produces listeriolysin O. This enzyme allows the therapeutic shRNA to escape from entry vesicles within the cytoplasm of the target cell. TRIP constructs are introduced into a competent non-pathogenic Escherichia coli strain, which encodes T7 RNA polymerase necessary for the T7 promoter-driven synthesis of shRNAs. A well-characterized cancer-associated target molecule for different RNAi strategies is ABCB1 (MDR1/P-glycoprotein, MDR1/P-gp). This ABC-transporter acts as a drug extrusion pump and mediates the "classical" ABCB1-mediated multidrug resistance (MDR) phenotype of human cancer cells which is characterized by a specific cross resistance pattern. Different ABCB1-expressing MDR cancer cells were treated with anti-ABCB1 shRNA expression vector bearing E. coli. This procedure resulted in activation of the RNAi pathways within the cancer cells and a considerable down regulation of the ABCB1 encoding mRNA as well as the corresponding drug extrusion pump. Accordingly, drug accumulation was enhanced in the pristine drug-resistant cancer cells and the MDR phenotype was reversed. By means of this model the data provide the proof-of-concept that tkRNAi is suitable for modulation of cancer-associated factors, e.g. ABCB1, in human cancer cells

Eco-Innovation Drivers in Value-Creating Networks : A Case Study of Ship Retrofitting Services

Previous studies discuss how regulatory, technological, and market drivers increasingly challenge manufacturing industries to adopt eco-innovations. However, the understanding of the process by which eco-innovations are developed and commercialized as a result of these drivers is not yet well-established, in particular because these drivers are perceived differently by the end-users and their suppliers. In this paper, we address the following research question: How do eco-innovation drivers shape processes in value-creating networks? To answer this question, we carried out a case study purposely selected to understand how eco-innovation drivers such as regulation, market pull, and technology interact and affect the eco-innovation decisions in a given industry. We analyzed the processes in an eco-innovation initiative about retrofitting old ships, contextualized in the maritime equipment and supply industry. The paper makes two novel contributions: First, we develop a framework that can support supply-network eco-innovation initiatives to deal with changes at regulatory, market, and technology levels. The framework includes elements such as value co-creation to explore technological opportunities emerging from the interaction of the drivers, or value-proposition development to align multiple actors’ interests in the network and agree on shared expectations to exploit the opportunities. Second, we contribute to the emerging research area on eco-innovation processes by highlighting the lesser-known role of value-creating network dynamics. Value-creating networks can be a platform for the development of more radical eco-innovations if actors in the networks can align their value creation and capture objectives.publishedVersio

Occupation time statistics of the random acceleration model

The random acceleration model is one of the simplest non-Markovian stochastic systems and has been widely studied in connection with applications in physics and mathematics. However, the occupation time and related properties are non-trivial and not yet completely understood. In this paper we consider the occupation time $T_+$ of the one-dimensional random acceleration model on the positive half-axis. We calculate the first two moments of $T_+$ analytically and also study the statistics of $T_+$ with Monte Carlo simulations. One goal of our work was to ascertain whether the occupation time $T_+$ and the time $T_m$ at which the maximum of the process is attained are statistically equivalent. For regular Brownian motion the distributions of $T_+$ and $T_m$ coincide and are given by L\'evy's arcsine law. We show that for randomly accelerated motion the distributions of $T_+$ and $T_m$ are quite similar but not identical. This conclusion follows from the exact results for the moments of the distributions and is also consistent with our Monte Carlo simulations.Comment: 10 pages, 4 figure

Analysis of asymmetric division of hematopoietic stem cells by continuous single cell observation

Every second, millions of blood cells are generated and destroyed by a mammalian organism. At the same time, a constant pool of hematopoietic stem cells that are able to self renew and reconstitute the entire blood system is maintained. The question of how HSC can achieve self renewal and differentiation at the same time remains unsolved. Asymmetric cell division has been proposed as a mechanism of asymmetric fate choice in HSC. Employing a new imaging and single cell tracking technology we address the question if HSC undergo asymmetric cell division. We observed divisional kinetics and marker expression of HSC and closely related MPP to elucidate if HSC produce asymmetrically fated daughter cells. We found that HSC show later cell cycle entry and also longer generation time in subsequent divisions compared to MPP and that this is an intrinsic property of HSC. However, HSC specific asymmetric generation time length of daughter cells is environmentally controlled and not intrinsic. The use of a live marker in our movies, CD48, which identifies cells that have lost the ability to reconstitute the bone marrow of a mouse for its lifetime, allows in vitro identification of asymmetric fate decisions between self renewal and differentiation. Quantification of cells with asymmetrically fated daughter cells, according to CD48 expression onset, reveals that most HSC produce asymmetric daughter cells, while most MPP do not. This behaviour is independent of the environment. This indicates that HSC intrinsically control asymmetric fates of daughter cells. Trying to elucidate the mechanism controlling these asymmetric fate decisions in HSC we chose candidates that are known to play a role in asymmetric fate decisions in other species or tissues. We examined if these candidates are segregated during HSC division and found no asymmetrically segregated protein when overexpressing Staufen1, Staufeni and Pumilio1 as fusions to VENUS protein. Furthermore, we analyzed if candidates had an influence on HSC and progenitor fate decisions in vitro and in vivo. We found that Staufen1 isoforms did not influence colony potential and lineage decision in vitro, Quaking1 isoforms influenced GM lineage decisions of progenitors in vitro and Pumilio1 overexpression led to reduced colony formation as well as altered GM lineage decisions. In HSC expansion conditions as assayed by reconstitution experiments, we found, that Staufen1 isoforms, Pumilio1 as well as Quaking1 isoforms did not allow HSC maintenance in recipient mice for 18 weeks. In HSC homeostatic conditions, as assayed in a transgenic mouse line, we found that Pumilio2 when expressed under Tie2 regulatory elements allows HSC maintenance in adult mice. Thus, we provide evidence that these genes, that were not implicated in hematopoiesis so far, could play a role in maintenance of HSC. In summary we show evidence that HSC produce asymmetric fates and that they control asymmetric fate choices between self renewal and differentiation intrinsically. We could exclude involvement of several candidate molecules in molecular control of asymmetric cell division. In addition, we provide a method to screen candidate genes for their role in asymmetric protein segregatio

Zum Deutschlandbild der nichtmarxistischen russischen Sozialisten

Diese Arbeit will das Deutschlandbild der nicht marxistischen russischen Sozialisten um die letzte Jahrhundertwende darstellen, der sogenannten Legalen Narodniki

Professionalization of kindergarten teachers with regards to the implementation of state-wide curriculum guidelines. General experiences of the research project QUASI Heidelberg

Bei der länderspezifischen Umsetzung von Bildungs- und Orientierungsplänen werden die unerwünschten Folgen eines fehlenden bundesweit geltenden und verbindlichen Orientierungsrahmens für den Elementarbereich sichtbar. Ihre Implementierung in den Kindertagesstätten erfolgt - wenn überhaupt - beliebig, unkoordiniert und unterliegt keinerlei Qualitätskontrolle. Am Beispiel des Projektes QUASI Heidelberg wird ein strukturierterer und umfassenderer Weg der Implementierung im Kontext des Baden-Württembergischen Orientierungsplans aufgezeigt. (DIPF/Orig.)The lack of standardized and compulsory national curriculum guidelines on early childhood education entails unintentional and undesirable consequences. Not only does it result in a variety of state-wide frameworks of reference, it also entails that curriculum guidelines are implemented by early childhood education facilities in an arbitrary, uncoordinated way, without adequate supervision. By contrast, the research project QUASI Heidelberg intends to highlight a more structured and comprehensive way of implementing these guidelines according to the framework of reference on early childhood education within the state of Baden-Wuerttemberg (Germany). (DIPF/Orig.

Challenges of creating and capturing value in open eco-innovation : Evidence from the maritime industry in Denmark

Author's accepted version (post-print).Available from 08/02/2021.Developing eco-innovations using open innovation comes with a distinct set of challenges as the dual goals of economic and environmental value creation produce tension that is not easily overcome in a multi-stakeholder network. These incongruent goals are inherent in an open eco-innovation network and potentially involve governmental agencies, regulators, and non-governmental organizations along with suppliers and other partners. Consequently, they add a layer of complexity to the creation and capture of value throughout the innovation network. Thus, in this study, we ask: What are the challenges in creating and capturing value in open eco-innovation networks? Based on an embedded case study of a network developing eco-innovation over a six-year period in the maritime industry in Denmark, this paper identifies challenges and links them to their impact on value creation and value capture. Our findings indicate that firms and partners are less innovative and more conservative in their approaches to innovation than has previously been observed in open-innovation partnerships. This research contributes to the eco-innovation knowledge base by demonstrating how extracting value from open eco-innovation is complicated as value is created at the micro and meso levels of the network, yet, a major goal of value capture is at the environment and social macro level. Thus, our results indicate that firms are less willing to commit resources and knowledge to co-creation, thereby negatively impacting value capture for the entire network, the society and/or the environment. Using open innovation to address “grand” societal challenges requires understanding value creation and value capture within this micro-meso-macro systemic framework of competing goals.acceptedVersio