The cell and molecular biological characterization of cell-cell junctions in mammalian heart valves

In view of the large proportion of cardiac cells represented by interstitial mesenchymal cells, in particular in the valves, of the frequency and importance of valve surgery, notably replacements, and of the numerous “tissue engineering” projects to provide artificial valve structures it is actually surprising to see how limited the cell and molecular biological knowledge of valvular interstitial cells (VICs) still is. Surprisingly, the molecular components of the special adherens junctions (AJs) of VICs have not yet been elucidated to a satisfying degree. Therefore, the AJs of adult and fetal VICs of human and animal (bovine, ovine and porcine) heart valves have been studied in situ and cell culture preparations, using light and electron microscopy, including immunolocalization techniques, protein as well as glycoprotein analysis by SDS-PAGE, followed by identification of the separated molecules using immunoblotting. In my thesis I could show that adult mammalian VICs in situ possess cell-cell adhering junctions only of the puncta adhaerentia AJ-type, comprising N-cadherin and cadherin-11 as constitutive transmembrane glycoproteins, anchored in cytoplasmic plaques containing α- and β-catenin, plakoglobin, proteins p120 and p0071 which are accompanied by actin-binding proteins such as afadin, vinculin, α-actinin and proteins ZO 1-3. In two-dimensional (2D) cell cultures of adult mammalian VICs of different species, this rather simple molecular AJ ensemble was surprisingly found to be modified by the acquisition of the desmosomal plaque protein plakophilin-2, in the total absence of desmosomal structures and other desmosomal proteins. In three-dimensional (3D) culture constructs mimicking a native valve matrix environment, it could be shown that AJ-plakophilin-2 gradually decreased or was even lost but was able to re-assemble when VICs were re-isolated from 3D constructs and grown in 2D culture again. Human and porcine fetal VICs in situ also presented plakophilin-2 in their AJs, showing that the phenomenon of plakophilin-2 acquisition is not an artefact of cell culture conditions. Primary cultures of porcine fetal VICs also revealed adventitious plakophilin-2. Even more surprisingly fetal endothelial cells of the endocardium – but only those located at the valves and not those at the myocardium – also displayed the addition of this desmosomal protein to their AJ plaques, whereas those of other regions of fetal vascular endothelia remained negative for this protein. Again unexpectedly, pathologically altered cells of adult heart valves, showing an elevated proliferative activity, did not present plakophilin-2 in their AJs. Such as fetal VICs showed only relatively low proliferative activity, these findings may lead to the hypothesis that the acquisition of plakophilin-2 might be rather the result of a general activation- than a proliferation-induced event. Correspondingly, an alternative concept for early valvulogenesis is proposed, differering from the presently prevailing “epithelial- (here better: endothelial-) mesenchymal-transition” (EMT) hypothesis, which is based on the assumption of an ab initio presence of mesenchymal cells of the VIC type, even in the early heart tube “anlage”. The advent of a single desmosome-typical protein, plakophilin-2, in VICs of fetal heart valves and in culture is not an isolated phenomenon as it fits in phenomena observed in recently identified forms of plakophilin-2-containing AJs (coniunctiones adhaerentes) found in other mesenchymal cells such as bone marrow-derived stem cells, malignantly transformed mesenchymal cell lines and certain soft tissue tumors. It is obvious that a more detailed characterization of VICs, notably their AJs, will be needed to provide a safe basis for replacement valve surgery using structures formed by cells grown in valvular cell cultures in vitro

Desmosomal Molecules In and Out of Adhering Junctions: Normal and Diseased States of Epidermal, Cardiac and Mesenchymally Derived Cells

Current cell biology textbooks mention only two kinds of cell-to-cell adhering junctions coated with the cytoplasmic plaques: the desmosomes (maculae adhaerentes), anchoring intermediate-sized filaments (IFs), and the actin microfilament-anchoring adherens junctions (AJs), including both punctate (puncta adhaerentia) and elongate (fasciae adhaerentes) structures. In addition, however, a series of other junction types has been identified and characterized which contain desmosomal molecules but do not fit the definition of desmosomes. Of these special cell-cell junctions containing desmosomal glycoproteins or proteins we review the composite junctions (areae compositae) connecting the cardiomyocytes of mature mammalian hearts and their importance in relation to human arrhythmogenic cardiomyopathies. We also emphasize the various plakophilin-2-positive plaques in AJs (coniunctiones adhaerentes) connecting proliferatively active mesenchymally-derived cells, including interstitial cells of the heart and several soft tissue tumor cell types. Moreover, desmoplakin has also been recognized as a constituent of the plaques of the complexus adhaerentes connecting certain lymphatic endothelial cells. Finally, we emphasize the occurrence of the desmosomal transmembrane glycoprotein, desmoglein Dsg2, out of the context of any junction as dispersed cell surface molecules in certain types of melanoma cells and melanocytes. This broadening of our knowledge on the diversity of AJ structures indicates that it may still be too premature to close the textbook chapters on cell-cell junctions

The (In-)Consistency of Literary Concepts. Operationalising, Annotating and Detecting Literary Comment

This paper explores how both annotation procedures and automatic detection (i.e. classifiers) can be used to assess the consistency of textual literary concepts. We developed an annotation tagset for the ‘literary comment’ – a frequently used but rarely defined concept – and its subtypes (interpretative comment, attitude comment and metanarrative/metafictional comment) and trained a multi-output and a binary classifier. The multi-output classifier shows F-scores of 28% for attitude comment, 36% for interpretative comment and 48% for meta comment, whereas the binary classifier achieves F-scores up to 59%. Crucially, both our annotation and the automatic classification struggle with the same subtypes of comment, although annotation and classification follow completely different procedures. Our findings suggest an inconsistency in the overall literary concept ‘comment’ and most prominently the subtypes ‘attitude comment’ and ‘interpretative comment’. As a best-practice-example, our approach illustrates that the contribution of Digital Humanities to Literary Studies may go beyond the automatic recognition of literary phenomena

Managerial power in the German model: the case of Bertelsmann and the antecedents of neoliberalism

Our article extends the research on authoritarian neoliberalism to Germany, through a history of the Bertelsmann media corporation – sponsor and namesake of Germany’s most influential neoliberal think-tank. Our article makes three conceptual moves. Firstly, we argue that conceptualizing German neoliberalism in terms of an ‘ordoliberal paradigm’ is of limited use in explaining the rise and fall of Germany’s distinctive socio-economic model (Modell Deutschland). Instead, we locate the origins of authoritarian tendencies in the corporate power exercised by managers rather than in the power of state-backed markets imagined by ordoliberals. Secondly, we focus on the managerial innovations of Bertelsmann as a key actor enmeshed with Modell Deutschland. We show that the adaptation of business management practices of an endogenous ‘Cologne School’ empowered Bertelsmann’s postwar managers to overcome existential crises and financial constraints despite being excluded from Germany’s corporate support network. Thirdly, we argue that their further development in the 1970s also enabled Bertelsmann to curtail and circumvent the forms of labour representation associated with Modell Deutschland. Inspired by cybernetic management theories that it used to limit and control rather than revive market competition among its workforce, Bertelsmann began to act and think outside the postwar settlement between capital and labour before the settlement’s hotly-debated demise since the 1990s

Transformative Materials to Create 3D Functional Human Tissue Models In Vitro in a Reproducible Manner

Recreating human tissues and organs in the petri dish to establish models as tools in biomedical sciences has gained momentum. These models can provide insight into mechanisms of human physiology, disease onset, and progression, and improve drug target validation, as well as the development of new medical therapeutics. Transformative materials play an important role in this evolution, as they can be programmed to direct cell behavior and fate by controlling the activity of bioactive molecules and material properties. Using nature as an inspiration, scientists are creating materials that incorporate specific biological processes observed during human organogenesis and tissue regeneration. This article presents the reader with state-of-the-art developments in the field of in vitro tissue engineering and the challenges related to the design, production, and translation of these transformative materials. Advances regarding (stem) cell sources, expansion, and differentiation, and how novel responsive materials, automated and large-scale fabrication processes, culture conditions, in situ monitoring systems, and computer simulations are required to create functional human tissue models that are relevant and efficient for drug discovery, are described. This paper illustrates how these different technologies need to converge to generate in vitro life-like human tissue models that provide a platform to answer health-based scientific questions.</p

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

Search for heavy resonances decaying to two Higgs bosons in final states containing four b quarks

A search is presented for narrow heavy resonances X decaying into pairs of Higgs bosons (H) in proton-proton collisions collected by the CMS experiment at the LHC at root s = 8 TeV. The data correspond to an integrated luminosity of 19.7 fb(-1). The search considers HH resonances with masses between 1 and 3 TeV, having final states of two b quark pairs. Each Higgs boson is produced with large momentum, and the hadronization products of the pair of b quarks can usually be reconstructed as single large jets. The background from multijet and t (t) over bar events is significantly reduced by applying requirements related to the flavor of the jet, its mass, and its substructure. The signal would be identified as a peak on top of the dijet invariant mass spectrum of the remaining background events. No evidence is observed for such a signal. Upper limits obtained at 95 confidence level for the product of the production cross section and branching fraction sigma(gg -> X) B(X -> HH -> b (b) over barb (b) over bar) range from 10 to 1.5 fb for the mass of X from 1.15 to 2.0 TeV, significantly extending previous searches. For a warped extra dimension theory with amass scale Lambda(R) = 1 TeV, the data exclude radion scalar masses between 1.15 and 1.55 TeV

Search for supersymmetry in events with one lepton and multiple jets in proton-proton collisions at root s=13 TeV

Peer reviewe

Measurement of the top quark mass using charged particles in pp collisions at root s=8 TeV

Peer reviewe

Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions

Peer reviewe