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Background and purpose - Due to the relative lack of reports on the medium- to long-term clinical and radiographic results of modular femoral cementless revision, we conducted this study to evaluate the medium- to long-term results of uncemented femoral stem revisions using the modular MRP-TITAN stem with distal diaphyseal fixation in a consecutive patient series.
Patients and methods - We retrospectively analyzed 163 femoral stem revisions performed between 1993 and 2001 with a mean follow-up of 10 (5-16) years. Clinical assessment included the Harris hip score (HHS) with reference to comorbidities and femoral defect sizes classified by Charnley and Paprosky. Intraoperative and postoperative complications were analyzed and the failure rate of the MRP stem for any reason was examined.
Results - Mean HHS improved up to the last follow-up (37 (SD 24) vs. 79 (SD 19); p < 0.001). 99 cases (61%) had extensive bone defects (Paprosky IIB-III). Radiographic evaluation showed stable stem anchorage in 151 cases (93%) at the last follow-up. 10 implants (6%) failed for various reasons. Neither a breakage of a stem nor loosening of the morse taper junction was recorded. Kaplan-Meier survival analysis revealed a 10-year survival probability of 97% (95% CI: 95-100).
Interpretation - This is one of the largest medium- to longterm analyses of cementless modular revision stems with distal diaphyseal anchorage. The modular MRP-TITAN was reliable, with a Kaplan-Meier survival probability of 97% at 10 years.
Despite its history of more than one hundred years, the phenomenon of
superconductivity has not lost any of its allure. During that time the concept
and perception of the superconducting state - both from an experimental and
theoretical point of view - has evolved in way that has
triggered increasing interest. What was initially believed to simply be the
disappearance of electrical resistivity, turned out to be a universal and
inevitable result of quantum statistics, characterized by many more
aspects apart from its zero resistivity. The insights of
BCS-theory eventually helped to uncover its deep connection to particle physics
and consequently led to the formulation of the Anderson-Higgs-mechanism. The
very core of this theory is the concept of gauge symmetry (breaking). Within the
framework of condensed-matter theory, gauge invariance is only one of several
symmetry groups which are crucial for the description and classification of
superconducting states. \\
In this thesis, we employ time-reversal, inversion, point group and spin
symmetries to investigate and derive possible Hamiltonians featuring spin-orbit
interaction in two and three spatial dimensions.
In particular, this thesis aims at a generalization of existing numerical
concepts to open up the path to spin-orbit coupled (non)centrosymmetric
superconductors in multi-orbital models.
This is done in a two-fold way: On the one hand, we formulate - based on the
Kohn-Luttinger effect - the perturbative renormalization group in the
weak-coupling limit. On the other hand, we define the spinful flow equations of
the effective action in the framework of functional renormalization, which is
valid for finite interaction strength as well. Both perturbative and functional
renormalization groups produce a low-energy effective (spinful) theory that
eventually gives rise to a particular superconducting state, which is investigated
on the level of the irreducible two-particle vertex. The symbiotic relationship
between both perturbative and functional renormalization can be traced back to
the fact that, while the perturbative renormalization at infinitesimal coupling
is only capable of dealing with the Cooper instability, the functional
renormalization can investigate a plethora of instabilities both in the
particle-particle and particle-hole channels. \\
Time-reversal and inversion are the two key symmetries, which are being used to
discriminate between two scenarios. If both time-reversal and inversion symmetry
are present, the Fermi surface will be two-fold degenerate and characterized by a
pseudospin degree of freedom. In contrast, if inversion symmetry is broken, the
Fermi surface will be spin-split and labeled by helicity. In both cases, we
construct the symmetry allowed states in the particle-particle as well as the
particle-hole channel. The methods presented are formally unified and implemented
in a modern object-oriented reusable and extendable C++ code.
This methodological implementation is employed to one member of both families of
pseudospin and helicity characterized systems. For the pseudospin case, we choose
the intriguing matter of strontium ruthenate, which has been heavily
investigated for already twenty-four years, but still keeps puzzling researchers.
Finally, as the helicity based application, we consider the oxide heterostructure
LaAlO$_{3}$/SrTiO$_{3}$, which became famous for its highly mobile two-
dimensional electron gas and is suspected to host topological superconductivity.
Various Mitsunobu conditions were investigated for a series of flavonolignans (silybin A, silybin B, isosilybin A, and silychristin A) to achieve either selective esterification in position C-23 or dehydration in a one-pot reaction yielding the biologically important enantiomers of hydnocarpin D, hydnocarpin and isohydnocarpin, respectively. This represents the only one-pot semi-synthetic method to access these flavonolignans in high yields.
We develop a joint formalism and numerical framework for analyzing the superconducting instability of metals from a weak coupling perspective. This encompasses the Kohn–Luttinger formulation of weak coupling renormalization group for superconductivity as well as the random phase approximation imposed on the diagrammatic expansion of the two-particle Green’s function. The central quantity to resolve is the effective interaction in the Cooper channel, for which we develop an optimized numerical framework. Our code is capable of treating generic multi-orbital models in two as well as three spatial dimensions and, in particular, arbitrary avenues of spin-orbit coupling.
A general theory for all classes of unconventional superconductors is still one of the unsolved key issues in condensed-matter physics. Actually, it is not yet fully settled if there is a common underlying pairing mechanism. Instead, it might be possible that several distinct sources for unconventional (not phonon-mediated) superconductivity have to be considered, or an electron-phonon interaction is not negligible. The focus of this thesis is on the most probable mechanism for the formation of Cooper pairs in unconventional superconductors, namely a strictly electronic one where spin fluctuations are the mediators. Studying different superconductors in this thesis, the emphasis is put on material-independent features of the pairing mechanism. In addition, the investigation of the phase diagrams enables a view on the vicinity of superconductivity. Thus, it is possible to clarify which competing quantum fluctuations enhance or weaken the propensity for a superconducting state. The broad range of superconducting materials requires the use of more than one numerical technique to study an appropriate microscopic description. This is not a problem but a big advantage because this facilitates the approach-independent description of common underlying physics. For this evaluation, the strongly correlated cuprates are simulated with the variational cluster approach. Especially the question of a pairing glue is taken into consideration. Furthermore, it is possible to distinguish between retarded and non-retarded contributions to the gap function. The cuprates are confronted with the cobaltate NaCoO and graphene. These weakly correlated materials are investigated with the functional renormalization group (fRG) and reveal a comprehensive phase diagram, including a d+id-wave superconductivity, which breaks time-reversal symmetry. The corresponding gap function is nodeless, but for NaCoO, it features a doping-dependent anisotropy. In addition, some general considerations on the kagome lattice are completing the discussion, where a sublattice interference dramatically affects the Fermi-surface instabilities, suppressing the usual spin-density wave and d+id-wave superconductivity. Thereby, some different fascinating charge and bond orders as well as a nematic are observable. In short, this thesis provides an insight to distinct classes of unconventional superconductors with appropriate simulation techniques. This facilitates to separate the material specific properties from the universal ones.
The paracaspase Malt1 is a central regulator of antigen receptor signaling that is frequently mutated in human lymphoma. As a scaffold, it assembles protein complexes for NF-kappa B activation, and its proteolytic domain cleaves negative NF-kappa B regulators for signal enforcement. Still, the physiological functions of Malt1-protease are unknown. We demonstrate that targeted Malt1-paracaspase inactivation induces a lethal inflammatory syndrome with lymphocyte-dependent neurodegeneration in vivo. Paracaspase activity is essential for regulatory T cell (Treg) and innate-like B cell development, but it is largely dispensable for overcoming Malt1-dependent thresholds for lymphocyte activation. In addition to NF-kappa B inhibitors, Malt1 cleaves an entire set of mRNA stability regulators, including Roquin-1, Roquin-2, and Regnase-1, and paracaspase inactivation results in excessive interferon gamma (IFN gamma) production by effector lymphocytes that drive pathology. Together, our results reveal distinct threshold and modulatory functions of Malt1 that differentially control lymphocyte differentiation and activation pathways and demonstrate that selective paracaspase blockage skews systemic immunity toward destructive autoinflammation.
We investigate the dispersion properties of ridge Bragg-reflection waveguides to deduce their phasematching characteristics. These are crucial for exploiting them as sources of parametric down-conversion (PDC). In order to estimate the phasematching bandwidth we first determine the group refractive indices of the interacting modes via Fabry-Perot experiments in two distant wavelength regions. Second, by measuring the spectra of the emitted PDC photons, we gain access to their group index dispersion. Our results offer a simple approach for determining the PDC process parameters in the spectral domain, and provide important feedback for designing such sources, especially in the broadband case.
The experimental technique predominantly employed within the scope of this Thesis constitutes one subarea of femtochemistry: the time-resolved spectroscopy of photoin-
duced chemical reactions in the liquid phase by means of molecular signatures in the mid-infrared (MIR) spectral range. Probing transient vibrational states, i.e., dynamic
changes in the vibrational motion of specic molecular subunits or functional Groups allows for a distinct separation and assignment of measured signals to emerging molecular species. For this purpose, one key building block is indispensable, which most of the investigations carried out within the eld of femtochemistry have in common: a coherent light source delivering ultrashort laser pulses with a temporal duration that matches the femtosecond time scale on which molecular motions typically occur. This instrumentation enables the observation of photoinduced chemical reactions from the
starting point|the excitation event to the appearance of intermediates to the nal formation of stable photoproducts after several pico- or nanoseconds.
This work comprises the acquisition and presentation of time-resolved spectroscopic data related to promising molecular systems upon photoexcitation as well as the im-
plementation and testing of experimental optical techniques both for the presented experiments but as well for experiments conceivable in the future. In addition, linear spectroscopy measurements and quantum-chemical simulations on the emerging chemical species have been carried out. In so doing, the primary processes and subse-
quently emerging reaction products of two compounds on a timescale of several nanoseconds after photoexcitation have been elucidated in great detail. Both compounds, the
[Mn(CO)3(tpm)]+ (tpm = tris(2-pyrazolyl)methane) CO-releasing molecule (CORM) and the 5-diazo Meldrum's acid (DMA), are of academic interest but in addition belong
to molecular classes that might be utilized in the near future as dark-stable prodrugs under physiological conditions or that are already utilized in industrial chemistry procedures, respectively. The ndings of both studies gave rise to implement and examine two techniques for prospective transient absorption experiments, namely the shaping and characterization of ultraviolet (UV) laser pulses and the recording of two-photon excitation spectra. Beyond that, since each of the depicted experiments is based on the detection of weak transient absorption signals in the MIR spectral region, two dif-
ferent detection schemes, via chirped-pulse upconversion (CPU) on the one hand and via direct multichannel MCT detection on the other hand, have been juxtaposed at the
conclusion of this work. Since both techniques are suitable in femtosecond pump-probe measurements but thereby exhibit individual strengths and weaknesses, a comparative study provides clarication of the respective pros and cons. The first study introduced within this work investigates the complex photochemistry
of DMA, a photoactive compound used in lithography and industrial chemistry. By femtosecond MIR transient absorption spectroscopy covering several nanoseconds, the
light-induced dynamics and ultrafast formation of several photoproducts from the manifold of reaction pathways have been disclosed to form a coherent picture of the overall
reaction scheme. After UV excitation of DMA dissolved in methanol to the second excited state S2, 70% of excited molecules relax back to the S0 ground state. In compet-
ing processes, they can either undergo an intramolecular Wolff rearrangement to form ketene, which reacts with a solvent molecule to an enol intermediate and further to carboxylate ester, or they rst relax to the DMA S1 state, from where they can isomerize to a diazirine. The third competing reaction channel, having the lowest quantum efficiency with respect to the rst two channels, is the formation of a singlet carbene out of the S1 state. From there an ylide can arise or, via an intersystem crossing, the triplet form of the carbene follows. Whereas the primary reaction steps occur on a picosecond timescale, the subsequently arising intermediates and stable photoproducts are formed
within a few hundreds to thousands of picoseconds. For a reliable identication of the involved compounds, density functional theory calculations on the normal modes and
Fourier-transform infrared spectroscopy of the reactant and the photoproducts in the chemical equilibrium accompany the analysis of the transient spectra. Additional experiments in ethanol and isopropanol led to slight spectral shifts as well as elongated time
constants due to steric hindrance in transient spectra connected with the ester Formation channel, further substantiating the assignment of the occurring reaction pathways and photoproducts.
The study demonstrated that the combination of linear and time-resolved spectroscopic measurements in conjunction with quantum-chemical calculations constitutes a powerful tool to unravel even highly complex photoreactions exhibiting multiple consecutive intermediate states within parallel reaction pathways. Although some of the individual reaction steps, for example the ketene formation via Wolff rearrangement, have been observed on ultrashort time scales before, this work encompassed the Observation of the whole set of appearing photoproducts of DMA in different alcohol solutions within several nanoseconds. In this sense, the ultrafast photochemistry of DMA represents a prototype example for a multisequential reaction scheme, elucidated by the capabilities of femtosecond MIR spectroscopy.
With a modified instrumentation concerning amongst others the system delivering the fundamental laser pulses or the generation of the UV pump pulses, the next ob-
jective within this work was to elucidate the primary processes upon UV Irradiation of a manganese tricarbonyl CORM in aqueous environment. The time-resolved
experiment was performed with two different pump wavelengths and furthermore supported by linear spectroscopy methods and time-dependent density functional theory (TDDFT) calculations on the excited states as well as DFT calculations on the ground
states. The measurements revealed that irradiating the compound with UV excitation pulses primarily leads to ultrafast photolysis of one CO ligand. Geminate recombination may occur within one picosecond but it remains a minor process as the photolyzed CO
group is liberated and the unoccupied coordination site is predominantly filled by an incoming solvent molecule. There was no evidence for hot CO bands, i.e., the remaining CO ligands|in the dicarbonyl photoproduct as well as in the intact CORM are not vibrationally excited through the UV excitation of the CORM. According to this, the excess energy merges into low-frequency vibrational modes associated with the molecule as a whole. Since studies on a macroscopic scale at irradiation times of several minutes prove that UV irradiation eventually leads to the release of two or even all three CO
ligands, further loss of CO most likely necessitates manganese oxidation or another interaction with light. To clarify the latter, a consecutive UV pulse was employed in order to excite the photoproducts subsequent to the initial pump interaction. However, the data obtained was not instructive enough to denitely exclude the manganese oxidation being responsible for the loss of further CO groups. Besides the exchange of a CO Group by a solvent molecule or the geminate recombination, the employment of two different excitation wavelengths in combination with ndings derived from the TDDFT calculations suggested another reaction process, namely the possibility that the excitation does not lead to any bond cleavage at all. As the CORM under investigation is tissue-selective and cytotoxic against cancer cells, knowledge of these rst photoinduced reaction steps is essential for a full understanding of its biological activity. Inspired by these two studies, experimental techniques for prospective transient absorption measurements have been implemented and tested within preparative measure-
ments. First, in the course of a UV-pump-MIR-probe experiment with specically tailored excitation pulses, one could pursue the aim of coherently controlling the outcome of a photoreaction in the liquid phase. Out of the rich photochemistry of DMA the vibrational signature of a particular molecular species might thereby serve as a feedback signal, which is a central part of a learning loop that adaptively determines the pulse shape that steers the quantum mechanical system upon photoexcitation into a desired direction. This motivated the installation and testing of devices by means of which the shaping and characterization of ultrashort laser pulses in the UV could be performed. Second, motivated by the biological applications of CORMs, one can imagine a scenario where a certain amount of CORMs is deposited inside cancerous tissue. Since the activation of CO loss by means of UV pulses is not possible due to the absorption characteristics of biological tissue, the simultaneous excitation via two photons from the visible spectral regime seems appealing. However, success or failure of such an application depends on whether the deposited compound efficiently absorbs two photons simultaneously, i.e., whether the two-photon absorption cross section is large enough. Therefore, a setup to record two-photon excitation spectra under full consideration of
the crucial laser pulse parameters like the pulse duration, energy and central wavelength was arranged and tested. The rst results were obtained with a commercially available reference system (Mn2CO10) but the setup as well as the described measurement and
data analysis procedure can easily be applied to record the two-photon absorption cross section of more promising molecular systems. Third, as the detection of probe pulses
in the MIR spectral region is part of each time-resolved measurement throughout this thesis, a comparison between the newly established technique of CPU and direct multi-
channel MCT detection is presented by means of pump{probe experiments on Mn2CO10 and Co4CO12 with a 1 kHz shot-to-shot data acquisition. It was shown that the CPU detection technique scores with its high spectral resolution and coverage of the easy-to-handle and more cost-effective CCD detectors. On the other hand, in the course of the additional nonlinear upconversion process intensity fluctuations of the chirped fundamental pulses are transferred to the probe spectrum in the visible regime. This entails a lower signal-to-noise ratio than the direct MCT detection, which can be compensated by an additional normalization procedure applied to the CPU probe pulses. As a consequence, the CPU detection scheme offers more flexibility for future investigations
employing MIR probe pulses. This is of great importance for many applications within the presented eld of femtochemistry as a huge variety of time-resolved investigations on a multitude of systems in the liquid phase is based on the detection of weak transient
absorption signals in the MIR spectral region.
Rare variants in at least 10 genes, including BRCA1, BRCA2, PALB2, ATM, and CHEK2, are associated with increased risk of breast cancer; however, these variants, in combination with common variants identified through genome-wide association studies, explain only a fraction of the familial aggregation of the disease. To identify further susceptibility genes, we performed a two-stage whole-exome sequencing study. In the discovery stage, samples from 1528 breast cancer cases enriched for breast cancer susceptibility and 3733 geographically matched unaffected controls were sequenced. Using five different filtering and gene prioritization strategies, 198 genes were selected for further validation. These genes, and a panel of 32 known or suspected breast cancer susceptibility genes, were assessed in a validation set of 6211 cases and 6019 controls for their association with risk of breast cancer overall, and by estrogen receptor (ER) disease subtypes, using gene burden tests applied to loss-of-function and rare missense variants. Twenty genes showed nominal evidence of association (p-value < 0.05) with either overall or subtype-specific breast cancer. Our study had the statistical power to detect susceptibility genes with effect sizes similar to ATM, CHEK2, and PALB2, however, it was underpowered to identify genes in which susceptibility variants are rarer or confer smaller effect sizes. Larger sample sizes would be required in order to identify such genes.
Soil salinity is an increasingly global problem which hampers plant growth and crop yield. Plant productivity depends on optimal water-use efficiency and photosynthetic capacity balanced by stomatal conductance. Whether and how stomatal behavior contributes to salt sensitivity or tolerance is currently unknown. This work identifies guard cell-specific signaling networks exerted by a salt-sensitive and salt-tolerant plant under ionic and osmotic stress conditions accompanied by increasing NaCl loads.
We challenged soil-grown Arabidopsis thaliana and Thellungiella salsuginea plants with short- and long-term salinity stress and monitored genome-wide gene expression and signals of guard cells that determine their function.
Arabidopsis plants suffered from both salt regimes and showed reduced stomatal conductance while Thellungiella displayed no obvious stress symptoms. The salt-dependent gene expression changes of guard cells supported the ability of the halophyte to maintain high potassium to sodium ratios and to attenuate the abscisic acid (ABA) signaling pathway which the glycophyte kept activated despite fading ABA concentrations.
Our study shows that salinity stress and even the different tolerances are manifested on a single cell level. Halophytic guard cells are less sensitive than glycophytic guard cells, providing opportunities to manipulate stomatal behavior and improve plant productivity.
Background:
Competing risks methodology allows for an event-specific analysis of the single components of composite time-to-event endpoints. A key feature of competing risks is that there are as many hazards as there are competing risks. This is not always well accounted for in the applied literature.
Methods:
We advocate a simulation point of view for understanding competing risks. The hazards are envisaged as momentary event forces. They jointly determine the event time. Their relative magnitude determines the event type. 'Empirical simulations' using data from a recent study on cardiovascular events in diabetes patients illustrate subsequent interpretation. The method avoids concerns on identifiability and plausibility known from the latent failure time approach.
Results:
The 'empirical simulations' served as a proof of concept. Additionally manipulating baseline hazards and treatment effects illustrated both scenarios that require greater care for interpretation and how the simulation point of view aids the interpretation. The simulation algorithm applied to real data also provides for a general tool for study planning.
Conclusions:
There are as many hazards as there are competing risks. All of them should be analysed. This includes estimation of baseline hazards. Study planning must equally account for these aspects.
Understanding extinction debts: spatio-temporal scales, mechanisms and a roadmap for future research
(2019)
Extinction debt refers to delayed species extinctions expected as a consequence of ecosystem perturbation. Quantifying such extinctions and investigating long‐term consequences of perturbations has proven challenging, because perturbations are not isolated and occur across various spatial and temporal scales, from local habitat losses to global warming. Additionally, the relative importance of eco‐evolutionary processes varies across scales, because levels of ecological organization, i.e. individuals, (meta)populations and (meta)communities, respond hierarchically to perturbations. To summarize our current knowledge of the scales and mechanisms influencing extinction debts, we reviewed recent empirical, theoretical and methodological studies addressing either the spatio–temporal scales of extinction debts or the eco‐evolutionary mechanisms delaying extinctions. Extinction debts were detected across a range of ecosystems and taxonomic groups, with estimates ranging from 9 to 90% of current species richness. The duration over which debts have been sustained varies from 5 to 570 yr, and projections of the total period required to settle a debt can extend to 1000 yr. Reported causes of delayed extinctions are 1) life‐history traits that prolong individual survival, and 2) population and metapopulation dynamics that maintain populations under deteriorated conditions. Other potential factors that may extend survival time such as microevolutionary dynamics, or delayed extinctions of interaction partners, have rarely been analyzed. Therefore, we propose a roadmap for future research with three key avenues: 1) the microevolutionary dynamics of extinction processes, 2) the disjunctive loss of interacting species and 3) the impact of multiple regimes of perturbation on the payment of debts. For their ability to integrate processes occurring at different levels of ecological organization, we highlight mechanistic simulation models as tools to address these knowledge gaps and to deepen our understanding of extinction dynamics.
Forest ecosystems fulfill a whole host of ecosystem functions that are essential for life on our planet. However, an unprecedented level of anthropogenic influences is reducing the resilience and stability of our forest ecosystems as well as their ecosystem functions. The relationships between drivers, stress, and ecosystem functions in forest ecosystems are complex, multi-faceted, and often non-linear, and yet forest managers, decision makers, and politicians need to be able to make rapid decisions that are data-driven and based on short and long-term monitoring information, complex modeling, and analysis approaches. A huge number of long-standing and standardized forest health inventory approaches already exist, and are increasingly integrating remote-sensing based monitoring approaches. Unfortunately, these approaches in monitoring, data storage, analysis, prognosis, and assessment still do not satisfy the future requirements of information and digital knowledge processing of the 21st century. Therefore, this paper discusses and presents in detail five sets of requirements, including their relevance, necessity, and the possible solutions that would be necessary for establishing a feasible multi-source forest health monitoring network for the 21st century. Namely, these requirements are: (1) understanding the effects of multiple stressors on forest health; (2) using remote sensing (RS) approaches to monitor forest health; (3) coupling different monitoring approaches; (4) using data science as a bridge between complex and multidimensional big forest health (FH) data; and (5) a future multi-source forest health monitoring network. It became apparent that no existing monitoring approach, technique, model, or platform is sufficient on its own to monitor, model, forecast, or assess forest health and its resilience. In order to advance the development of a multi-source forest health monitoring network, we argue that in order to gain a better understanding of forest health in our complex world, it would be conducive to implement the concepts of data science with the components: (i) digitalization; (ii) standardization with metadata management after the FAIR (Findability, Accessibility, Interoperability, and Reusability) principles; (iii) Semantic Web; (iv) proof, trust, and uncertainties; (v) tools for data science analysis; and (vi) easy tools for scientists, data managers, and stakeholders for decision-making support.
Understanding human navigation behavior has implications for a wide range of application scenarios. For example, insights into geo-spatial navigation in urban areas can impact city planning or public transport. Similarly, knowledge about navigation on the web can help to improve web site structures or service experience.
In this work, we focus on a hypothesis-driven approach to address the task of understanding human navigation: We aim to formulate and compare ideas — for example stemming from existing theory, literature, intuition, or previous experiments — based on a given set of navigational observations. For example, we may compare whether tourists exploring a city walk “short distances” before taking their next photo vs. they tend to "travel long distances between points of interest", or whether users browsing Wikipedia "navigate semantically" vs. "click randomly".
For this, the Bayesian method HypTrails has recently been proposed. However, while HypTrails is a straightforward and flexible approach, several major challenges remain:
i) HypTrails does not account for heterogeneity (e.g., incorporating differently behaving user groups such as tourists and locals is not possible), ii) HypTrails does not support the user in conceiving novel hypotheses when confronted with a large set of possibly relevant background information or influence factors, e.g., points of interest, popularity of locations, time of the day, or user properties, and finally iii) formulating hypotheses can be technically challenging depending on the application scenario (e.g., due to continuous observations or temporal constraints). In this thesis, we address these limitations by introducing various novel methods and tools and explore a wide range of case studies.
In particular, our main contributions are the methods MixedTrails and SubTrails which specifically address the first two limitations: MixedTrails is an approach for hypothesis comparison that extends the previously proposed HypTrails method to allow formulating and comparing heterogeneous hypotheses (e.g., incorporating differently behaving user groups). SubTrails is a method that supports hypothesis conception by automatically discovering interpretable subgroups with exceptional navigation behavior. In addition, our methodological contributions also include several tools consisting of a distributed implementation of HypTrails, a web application for visualizing geo-spatial human navigation in the context of background information, as well as a system for collecting, analyzing, and visualizing mobile participatory sensing data.
Furthermore, we conduct case studies in many application domains, which encompass — among others — geo-spatial navigation based on photos from the photo-sharing platform Flickr, browsing behavior on the social tagging system BibSonomy, and task choosing behavior on a commercial crowdsourcing platform. In the process, we develop approaches to cope with application specific subtleties (like continuous observations and temporal constraints). The corresponding studies illustrate the variety of domains and facets in which navigation behavior can be studied and, thus, showcase the expressiveness, applicability, and flexibility of our methods. Using these methods, we present new aspects of navigational phenomena which ultimately help to better understand the multi-faceted characteristics of human navigation behavior.
The global-local sustainable development and climate change adaptation policy, and the emerging political discourse on the value of local Adaptation, have positioned the local institutions and their governance space within the strategic enclaves of multilevel governance system. Such shifts have transformed the context for sustainable Nature Based Tourism (NBT) development and adaptation in Nepal in general, and its protected areas, in particular. The emerging institutional adaptation discourse suggests on the need to link tourism development, adaptation and governance within the sustainability concept, and also to recognize the justice and inclusive dimensions of local adaptation. However, sociological investigation of institutional adaptation, particularly at the interface between sustainability, justice and inclusive local adaptation is an undertheorized research topic.
This exploratory study examined the sociological process of the institutional adaptation, especially the social resilience and adaptive governance capacities of the NBT institutions, in 7 Village Development Committees of the Mustang district, a popular destination in the Annapurna Conservation Area, Nepal. Using the sphere (a dynamic social space concept) and quality of governance as the analytical framework, the integrative adaptation as the methodological approach and the case study action research method, the study investigated and generated a holistic picture on the state of the social resilience and adaptive governance capacities of the NBT institutions.
The findings show institutional social resilience capacities to be contingent on socio-political construction of adaptation knowledge and power. Factors influencing such constructions among NBT institutions include: the site and institutions specific political, economic and environmental dispositions; the associated socio-political processes of knowledge constructions and volition action; and the social relationships and interaction, operating within the spheres and at multiple governance levels. The adaptive governance capacities hinge on the institutional arrangements, the procedural aspects of adaptation governance and the governmentality. These are reflective of the diverse legal frameworks, the interiority perspective of the decision making and governance practices of the NBT institutions.
In conclusion, it is argued that effective local adaptation in the Mustang district is contingent on the adaptation and institutional dynamics of the NBT institutions, consisting of the cognitive, subjective, process and procedural aspects of the adaptation knowledge production and its use.
Argumentation and proof have played a fundamental role in mathematics education in recent years. The author of this dissertation would like to investigate the development of the proving process within a dynamic geometry system in order to support tertiary students understanding the proving process. The strengths of this dynamic system stimulate students to formulate conjectures and produce arguments during the proving process. Through empirical research, we classified different levels of proving and proposed a methodological model for proving. This methodological model makes a contribution to improve students’ levels of proving and develop their dynamic visual thinking. We used Toulmin model of argumentation as a theoretical model to analyze the relationship between argumentation and proof. This research also offers some possible explanation so as to why students have cognitive difficulties in constructing proofs and provides mathematics educators with a deeper understanding on the proving process within a dynamic geometry system.
Ubiquitylation is a protein post translational modification, in which ubiquitin is covalently attached to target protein substrates resulting in diverse cellular outcomes. Besides ubiquitin, various ubiquitin-like proteins including FAT10 exist, which are also conjugated to target proteins. The underlying modification mechanisms are conserved. In the initial step, ubiquitin or a ubiquitin-like protein is thioester-linked to a catalytic cysteine in the E1activating enzyme in an ATP-dependent manner. The respective protein modifier is then transferred to an E2 conjugating enzyme in a transthioesterification reaction. Finally, an E3 ubiquitin ligase E3 catalyzes the covalent attachment of the protein modifier to a substrate. In the case of ubiquitin, multiple ubiquitin molecules can be attached to a substrate in the form of either linear or branched polyubiquitin chains but also as single ubiquitin modifications. Depending on the nature of the ubiquitin chain, the substrates are destined to various cellular processes such as their targeted destruction by the proteasome but also non-degradative outcomes may occur.
As stated above FAT10 is a ubiquitin-like protein modifier which typically targets proteins for proteasomal degradation. It consists of two ubiquitin-like domains and is mainly expressed in cells of the human immune system. The reported involvement of FAT10 modifications in cancers and other diseases has caught the attention of the scientific community as an inhibition of the FAT10ylation process may provide avenues for novel therapeutic approaches. UBA6 is the E1 activating enzyme that resides at the apex of the FAT10 proteasomal degradation pathway. UBA6 not only recognizes FAT10 but can also activate ubiquitin as efficiently as the ubiquitin specific E1 UBA1. The dual specificity of UBA6 may complicate the inhibition FAT10ylation since targeting the active site of UBA6 will also inhibit the UBA6-catalyzed ubiquitin activation. Therefore, it is important to understand the underlying principles for the dual specificity of UBA6 prior to the development of compounds interfering with FAT10ylation.
In this thesis important novel insights into the structure and function of UBA6 were derived by X-ray crystallography and biochemical methods. The first crystal structure of UBA6 reveals the multidomain architecture of this enzyme in atomic detail. The enzyme is composed of a rigid core including its active and inactive adenylation domains as well as a 4 helix bundle. Overall, the molecule adopts a “Y” shape architecture with the core at the base and the first and second catalytic half domains forming one arm of the “Y” and the ubiquitin fold domain constituting the other arm. While UBA6 shares the same domain architecture as UBA1, substantial differences were revealed by the crystal structure. In particular, the first catalytic half domain undergoes a significant shift to a position more distal from the core. This rigid body movement is assumed to generate room to accommodate the second ubiquitin-like domain of FAT10. Differences are also observed in a hydrophobic platform between the core and the first catalytic half domain and the adenylation active site in the core, which together from the binding sites for ubiquitin and FAT10. Site directed mutagenesis of key residues in these areas altered the UBA6-catalyzed activation of ubiquitin and FAT10. UBA6 variants were generated with the goal of trying to block the activation of FAT10 while still maintaining that of ubiquitin activation, in order to fully explain the dual specificity of UBA6. However, none of these mutations could block the activation of FAT10, while some of these UBA6 variants blocked ubiquitin activation. Preliminary inhibition assays with a group of E1 inhibitors belonging to the adenosyl sulfamate family demonstrated potent inhibition of FAT10ylation for two compounds. The dual specificity of UBA6 hence needs to be further examined by biochemical and structural methods. In particular, the structure of a complex between UBA6 and ubiquitin or FAT10 would provide key insights for further biochemical studies, ultimately allowing the targeted inhibition of the FAT10ylation machinery.
Humans spontaneously blink several times a minute. These blinks are strongly modulated during various cognitive task. However, the precise function of blinking and the reason for their modulation has not been fully understood. In the present work, I investigated the function of spontaneous blinks through various perceptual and cognitive tasks. Previous research has revealed that blinks rates decrease during some tasks but increase during others. When trying to understand these seemingly contradictory results, I observed that blink reduction occurs when one engages with an external input. For instance, a decrease has been observed due to the onset of a stimulus, sensory input processing and attention towards sensory input. However, for activities that do not involve such an engagement, e.g. imagination, daydreaming or creativity, the blink rate has been shown to increase. To follow up on the proposed hypothesis, I distinguished tasks that involve the processing of an external stimulus and tasks that involve disengagement.
In the first part of the project, I explored blinking during stimulus engagement. If the probability of blinking is low when engaging with the stimulus, then one should find a reduction in blinks specifically during the time period of processing but not during sensory input per se. To this end, in study 1, I tested the influence of task-relevant information duration on blink timing and additionally manipulated the overall sensory input using a visual and an auditory temporal simultaneity judgement task. The results showed that blinks were suppressed longer for longer periods of relevant information or in other words, blinks occurred at the end of relevant information processing for both the visual and the auditory modality. Since relevance is mediated through top-down processes, I argue that the reduction in blinks is a top-down driven suppression. In studies 2 and 3, I again investigated stimulus processing, but in this case, processing was triggered internally and not based on specific changes in the external input. To this end, I used bistable stimuli, in which the actual physical stimulus remains constant but their perception switches between different interpretations. Studies on the involvement of attention in such bistable perceptual changes indicate that the sensory input is reprocessed before the perceptual switch. The results revealed a reduction in eye blink rates before the report of perceptual switches. Importantly, I was able to decipher that the decrease was not caused by the perceptual switch or the behavioral response but likely started before the internal switch. Additionally, periods between a blink and a switch were longer than interblink intervals, indicating that blinks were followed by a period of stable percept. To conclude, the first part of the project revealed that there is a top-down driven blink suppression during the processing of an external stimulus.
In the second part of the project, I extended the idea of blinks marking the disengagement from external processing and tested if blinking is associated with better performance during internally directed processes. Specifically, I investigated divergent thinking, an aspect of creativity, and the link between performance and blink rates as well as the effect of motor restriction. While I could show that motor restriction was the main factor influencing divergent thinking, the relationship between eye blink rates and creative output also depended on restriction. Results showed that higher blink rates were associated with better performance during free movement, but only between subjects. In other words, subjects who had overall higher blink rates scored better in the task, but when they were allowed to sit or walk freely. Within a single subject, trial with higher blink rates were not associated with better performance. Therefore, possibly, people who are able to disengage easily, as indicated by an overall high blink rate, perform better in divergent thinking tasks. However, the link between blink rate and internal tasks is not clear at this point. Indeed, a more complex measurement of blink behavior might be necessary to understand the relationship.
In the final part of the project, I aimed to further understand the function of blinks through their neural correlates. I extracted the blink-related neural activity in the primary visual cortex (V1) of existing recordings of three rhesus monkeys during different sensory processing states. I analyzed spike related multi-unit responses, frequency dependent power changes, local field potentials and laminar distribution of activity while the animal watched a movie compared to when it was shown a blank screen. The results showed a difference in blink-related neural activity dependent on the processing state. This difference suggests a state dependent function of blinks.
Taken altogether, the work presented in this thesis suggests that eye blinks have an important function during cognitive and perceptual processes. Blinks seem to facilitate a disengagement from the external world and are therefore suppressed during intended processing of external stimuli.
1. Species assemblages of naturally disturbed habitats are governed by the prevailing disturbance regime. Consequently, stochastic flood events affect river banks and the inhabiting biota. Predatory arthropods occupy predominantly river banks in relation to specific habitat conditions. Therefore, species sorting and stochastic processes as induced by flooding are supposed to play important roles in structuring riparian arthropod assemblages in relation to their habitat preference and dispersal ability. 2. To ascertain whether assemblages of spiders and carabid beetles from disturbed river banks are structured by stochastic or sorting mechanisms, diversity patterns and assemblage-wide trait-displacements were assessed based on pitfall sampling data. We tested if flooding disturbance within a lowland river reach affects diversity patterns and trait distribution in both groups. 3. Whereas the number of riparian spider species decreased considerably with increased flooding, carabid beetle diversity benefited from intermediate degrees of flooding. Moreover, regression analyses revealed trait-displacements, reflecting sorting mechanisms particularly for spiders. Increased flooding disturbance was associated with assemblage-wide increases of niche breadth, shading and hygrophilic preference and ballooning propensity for spider (sub)families. Trait patterns were comparable for Bembidiini carabids, but were less univocal for Pterostichini species. Body size decreased for lycosid spiders and Bembidiini carabids with increased flooding, but increased in linyphiid spiders and Pterostichini carabids. 4. Our results indicate that mainly riparian species are disfavoured by either too high or too low degrees of disturbance, whereas eurytopic species benefit from increased flooding. Anthropogenic alterations of flooding disturbance constrain the distribution of common hygrophilous species and/or species with high dispersal ability, inducing shifts towards less specialized arthropod assemblages. River banks with divergent degrees of flooding impact should be maintained throughout dynamic lowland river reaches in order to preserve typical riparian arthropod assemblages.
The rapid appearance of resistant malarial parasites after introduction of atovaquone (ATQ) drug has prompted the search for new drugs as even single point mutations in the active site of Cytochrome b protein can rapidly render ATQ ineffective. The presence of Y268 mutations in the Cytochrome b (Cyt b) protein is previously suggested to be responsible for the ATQ resistance in Plasmodium falciparum (P. falciparum). In this study, we examined the resistance mechanism against ATQ in P. falciparum through computational methods. Here, we reported a reliable protein model of Cyt bc1 complex containing Cyt b and the Iron-Sulphur Protein (ISP) of P. falciparum using composite modeling method by combining threading, ab initio modeling and atomic-level structure refinement approaches. The molecular dynamics simulations suggest that Y268S mutation causes ATQ resistance by reducing hydrophobic interactions between Cyt bc1 protein complex and ATQ. Moreover, the important histidine contact of ATQ with the ISP chain is also lost due to Y268S mutation. We noticed the induced mutation alters the arrangement of active site residues in a fashion that enforces ATQ to find its new stable binding site far away from the wild-type binding pocket. The MM-PBSA calculations also shows that the binding affinity of ATQ with Cyt bc1 complex is enough to hold it at this new site that ultimately leads to the ATQ resistance.
Understanding the Performance of Different Packet Reception and Timestamping Methods in Linux
(2023)
This document briefly presents some renowned packet reception techniques for network packets in Linux systems. Further, it compares their performance when measuring packet timestamps with respect to throughput and accuracy. Both software and hardware timestamps are compared, and various parameters are examined, including frame size, link speed, network interface card, and CPU load. The results indicate that hardware timestamping offers significantly better accuracy with no downsides, and that packet reception techniques that avoid system calls offer superior measurement throughput.
The ubiquitination of proteins serves as molecular signal to control an enormous number of physiological processes and its dysregulation is connected to human diseases like cancer. The versatility of this signal stems from the diverse ways by which ubiquitin can be attached to its targets. Thus, specificity and tight regulation of the ubiquitination are pivotal requirements of ubiquitin signaling. Ubiquitin-conjugating enzymes (E2s) act at the heart of the ubiquitination cascade, transferring ubiquitin from a ubiquitin-activating enzyme (E1) to a ubiquitin ligase (E3) or substrate. When cooperating with a RING-type E3, ubiquitin-conjugating enzymes can determine linkage specificity in ubiquitin chain formation. Our understanding of the regulation of E2 activities is still limited at a structural level.
The work described here identifies two regulation mechanisms in UBE2S, a cognate E2 of the human RING-type E3 anaphase-promoting complex/cyclosome (APC/C). UBE2S elongates ubiquitin chains on APC/C substrates in a Lys11 linkage-specific manner, thereby targeting these substrates for degradation and driving mitotic progression. In addition, UBE2S was found to have a role in DNA repair by enhancing non-homologous end-joining (NHEJ) and causing transcriptional arrest at DNA damage sites in homologous recombination (HR). Furthermore, UBE2S overexpression is a characteristic feature of many cancer types and is connected to poor prognosis and diminished response to therapy.
The first regulatory mechanism uncovered in this thesis involves the intramolecular auto-ubiquitination of a particular lysine residue (Lys+5) close to the active site cysteine, presumably through conformational flexibility of the active site region. The Lys+5-linked ubiquitin molecule adopts a donor-like, ‘closed’ orientation towards UBE2S, thereby conferring auto-inhibition. Notably, Lys+5 is a major physiological ubiquitination site in ~25% of the human E2 enzymes, thus providing regulatory opportunities beyond UBE2S. Besides the active, monomeric state and the auto-inhibited state caused by auto-ubiquitination, I discovered that UBE2S can adopt a dimeric state. The latter also provides an auto-inhibited state, in which ubiquitin transfer is blocked via the obstruction of donor binding. UBE2S dimerization is promoted by its unique C-terminal extension, suppresses auto-ubiquitination and thereby the proteasomal degradation of UBE2S.
Taken together, the data provided in this thesis illustrate the intricate ways by which UBE2S activity is fine-tuned and the notion that structurally diverse mechanisms have evolved to restrict the first step in the catalytic cycle of E2 enzymes.
Aggression and deficient cognitive control problems are widespread in psychiatric disorders, including major depressive disorder (MDD). These abnormalities are known to contribute significantly to the accompanying functional impairment and the global burden of disease. Progress in the development of targeted treatments of excessive aggression and accompanying symptoms has been limited, and there exists a major unmet need to develop more efficacious treatments for depressed patients. Due to the complex nature and the clinical heterogeneity of MDD and the lack of precise knowledge regarding its pathophysiology, effective management is challenging. Nonetheless, the aetiology and pathophysiology of MDD has been the subject of extensive research and there is a vast body of the latest literature that points to new mechanisms for this disorder. Here, we overview the key mechanisms, which include neuroinflammation, oxidative stress, insulin receptor signalling and abnormal myelination. We discuss the hypotheses that have been proposed to unify these processes, as many of these pathways are integrated for the neurobiology of MDD. We also describe the current translational approaches in modelling depression, including the recent advances in stress models of MDD, and emerging novel therapies, including novel approaches to management of excessive aggression, such as anti-diabetic drugs, antioxidant treatment and herbal compositions.
The Visual Editor for XML (Vex)[1] used by TextGrid [2]and other applications has got rendering and layout engines. The layout engine is well documented but the rendering engine is not. This lack of documenting the rendering engine has made refactoring and extending the editor hard and tedious. For instance many CSS2.1 and upcoming CSS3 properties have not been implemented. Software developers in different projects such as TextGrid using Vex would like to update its CSS rendering engine in order to provide advanced user interfaces as well as support different document types. In order to minimize the effort of extending Vex functionality, I found it beneficial to write a basic documentation about Vex software architecture in general and its CSS rendering engine in particular. The documentation is mainly based on the idea of architectural layered diagrams. In fact layered diagrams can help developers understand software’s source code faster and easier in order to alter it, and fix errors. This paper is written for the purpose of providing direct support for exploration in the comprehension process of Vex source code. It discusses Vex software architecture. The organization of packages that make up the software, the architecture of its CSS rendering engine, an algorithm explaining the working principle of its rendering engine are described.
Three-dimensional capturing of underwater archeological sites or sunken shipwrecks can support important documentation purposes. In this study, a novel 3D scanning system based on structured illumination is introduced, which supports cultural heritage documentation and measurement tasks in underwater environments. The newly developed system consists of two monochrome measurement cameras, a projection unit that produces aperiodic sinusoidal fringe patterns, two flashlights, a color camera, an inertial measurement unit (IMU), and an electronic control box. The opportunities and limitations of the measurement principles of the 3D scanning system are discussed and compared to other 3D recording methods such as laser scanning, ultrasound, and photogrammetry, in the context of underwater applications. Some possible operational scenarios concerning cultural heritage documentation are introduced and discussed. A report on application activities in water basins and offshore environments including measurement examples and results of the accuracy measurements is given. The study shows that the new 3D scanning system can be used for both the topographic documentation of underwater sites and to generate detailed true-scale 3D models including the texture and color information of objects that must remain under water.
There is great interest in affordable, precise and reliable metrology underwater:
Archaeologists want to document artifacts in situ with high detail.
In marine research, biologists require the tools to monitor coral growth and geologists need recordings to model sediment transport.
Furthermore, for offshore construction projects, maintenance and inspection millimeter-accurate measurements of defects and offshore structures are essential.
While the process of digitizing individual objects and complete sites on land is well understood and standard methods, such as Structure from Motion or terrestrial laser scanning, are regularly applied, precise underwater surveying with high resolution is still a complex and difficult task.
Applying optical scanning techniques in water is challenging due to reduced visibility caused by turbidity and light absorption.
However, optical underwater scanners provide significant advantages in terms of achievable resolution and accuracy compared to acoustic systems.
This thesis proposes an underwater laser scanning system and the algorithms for creating dense and accurate 3D scans in water.
It is based on laser triangulation and the main optical components are an underwater camera and a cross-line laser projector.
The prototype is configured with a motorized yaw axis for capturing scans from a tripod.
Alternatively, it is mounted to a moving platform for mobile mapping.
The main focus lies on the refractive calibration of the underwater camera and laser projector, the image processing and 3D reconstruction.
For highest accuracy, the refraction at the individual media interfaces must be taken into account.
This is addressed by an optimization-based calibration framework using a physical-geometric camera model derived from an analytical formulation of a ray-tracing projection model.
In addition to scanning underwater structures, this work presents the 3D acquisition of semi-submerged structures and the correction of refraction effects.
As in-situ calibration in water is complex and time-consuming, the challenge of transferring an in-air scanner calibration to water without re-calibration is investigated, as well as self-calibration techniques for structured light.
The system was successfully deployed in various configurations for both static scanning and mobile mapping.
An evaluation of the calibration and 3D reconstruction using reference objects and a comparison of free-form surfaces in clear water demonstrate the high accuracy potential in the range of one millimeter to less than one centimeter, depending on the measurement distance.
Mobile underwater mapping and motion compensation based on visual-inertial odometry is demonstrated using a new optical underwater scanner based on fringe projection.
Continuous registration of individual scans allows the acquisition of 3D models from an underwater vehicle.
RGB images captured in parallel are used to create 3D point clouds of underwater scenes in full color.
3D maps are useful to the operator during the remote control of underwater vehicles and provide the building blocks to enable offshore inspection and surveying tasks.
The advancing automation of the measurement technology will allow non-experts to use it, significantly reduce acquisition time and increase accuracy, making underwater metrology more cost-effective.
Unexpected edge conduction in mercury telluride quantum wells under broken time-reversal symmetry
(2015)
The realization of quantum spin Hall effect in HgTe quantum wells is considered a milestone in the discovery of topological insulators. Quantum spin Hall states are predicted to allow current flow at the edges of an insulating bulk, as demonstrated in various experiments. A key prediction yet to be experimentally verified is the breakdown of the edge conduction under broken time-reversal symmetry. Here we first establish a systematic framework for the magnetic field dependence of electrostatically gated quantum spin Hall devices. We then study edge conduction of an inverted quantum well device under broken time-reversal symmetry using microwave impedance microscopy, and compare our findings to a noninverted device. At zero magnetic field, only the inverted device shows clear edge conduction in its local conductivity profile, consistent with theory. Surprisingly, the edge conduction persists up to 9 T with little change. This indicates physics beyond simple quantum spin Hall model, including material-specific properties and possibly many-body effects.
African trypanosomes cause sleeping sickness in humans and nagana in cattle. These unicellular parasites are transmitted by the bloodsucking tsetse fly. In the mammalian host’s circulation, proliferating slender stage cells differentiate into cell cycle-arrested stumpy stage cells when they reach high population densities. This stage transition is thought to fulfil two main functions: first, it auto-regulates the parasite load in the host; second, the stumpy stage is regarded as the only stage capable of successful vector transmission. Here, we show that proliferating slender stage trypanosomes express the mRNA and protein of a known stumpy stage marker, complete the complex life cycle in the fly as successfully as the stumpy stage, and require only a single parasite for productive infection. These findings suggest a reassessment of the traditional view of the trypanosome life cycle. They may also provide a solution to a long-lasting paradox, namely the successful transmission of parasites in chronic infections, despite low parasitemia.
The new ellipsocephaloid trilobite species Kingaspidoides spinirecurvatus has a spectacular morphology because of a unique set of two long and anteriorly recurved spines on the occipital ring and the axial ring of thoracic segment 8. Together with the long genal spines this whimsical dorsally directed spine arrangement is thought to act as a non-standard protective device against predators. This is illustrated by the body posture during different stages of enrolment, contrasting with the more sophisticated spinosities seen in later trilobites, which are discussed in brief. Kingaspidoides spinirecurvatus from the lower–middle Cambrian boundary interval of the eastern Anti-Atlas in Morocco has been known for about two decades, with specimens handled as precious objects on the fossil market. Similar, but far less spectacular, spine arrangements on the thoracic axial rings are known from other ellipsocephaloid trilobites from the Anti-Atlas of Morocco and the Franconian Forest region of Germany. This suggests that an experimental phase of spine development took place within the Kingaspi-doides clade during the early–middle Cambrian boundary interval.
A multitude of human tissues, such as bones, tendons, or muscles, are characterized by a hierarchical and highly ordered structure. In many cases, the loss of these tissues requires reconstruction using biocompatible replacement materials. In the field of bone replacement, the pore structure of the material has a crucial influence. Anisotropic porosity would have the advantage of facilitating the ingrowth of cells and newly formed blood vessels as well as the transport of nutrients.
In this thesis, scaffolds with a highly ordered and anisotropic pore structure were fabricated using unidirectional freezing.
Systematic investigations were carried out on biopolymer solutions (alginate and chitosan) to gain a deeper understanding of the freeze-structuring process. The knowledge gained was then applied to the development of anisotropically structured bone substitute materials. Here, the previously existing material platform for anisotropically structured calcium phosphates was extended to low-temperature phases such as calcium deficient hydroxyapatite (CDHA) or the secondary phosphates monetite and brushite.
After the implantation of a biomaterial, the inevitably triggered initial immune response plays a key role in the success of a graft, with immune cells such as neutrophils or macrophages being of particular importance. In this thesis, the influence of anisotropically structured alpha-TCP and CDHA scaffolds as well as their unstructured references on human monocytes/macrophages was investigated. Macrophages produced extracellular traps (ETs) due to mineral nanoparticles formed by the binding of phosphate and calcium ions to human platelet lysate. In particular, incubation of alpha-TCP samples in lysate containing cell culture medium resulted in pronounced particle formation and enhanced release of ETs.
Within this thesis a new philosophy in monitoring spacecrafts is presented: the
unification of the various kinds of monitoring techniques used during the
different lifecylce phases of a spacecraft.
The challenging requirements being set for this monitoring framework are:
- "separation of concerns" as a design principle (dividing the steps of logging
from registered sources, sending to connected sinks and displaying of
information),
- usage during all mission phases,
- usage by all actors (EGSE engineers, groundstation operators, etc.),
- configurable at runtime, especially regarding the level of detail of logging
information, and
- very low resource consumption.
First a prototype of the monitoring framework was developed as a support library
for the real-time operating system
RODOS. This prototype was tested on dedicated hardware platforms relevant for
space, and also on a satellite demonstrator used for educational purposes.
As a second step, the results and lessons learned from the development and usage
of this prototype were transfered to a real space mission: the first satellite
of the DLR compact satellite series - a space based platform for DLR's own
research activities. Within this project, the software of the avionic subsystem
was supplemented by a powerful logging component, which enhances the traditional
housekeeping capabilities and offers extensive filtering and debugging
techniques for monitoring and FDIR needs. This logging component is the major
part of the flight version of the monitoring framework. It is completed by
counterparts running on the development computers and as well as the EGSE
hardware in the integration room, making it most valuable already in the
earliest stages of traditional spacecraft development.
Future plans in terms of adding support from the groundstation as well will lead
to a seamless integration of the monitoring framework not only into to the
spacecraft itself, but into the whole space system.
The bounded input bounded output (BIBO) stability for a nonlinear Caputo fractional system with time‐varying bounded delay and nonlinear output is studied. Utilizing the Razumikhin method, Lyapunov functions and appropriate fractional derivatives of Lyapunov functions some new bounded input bounded output stability criteria are derived. Also, explicit and independent on the initial time bounds of the output are provided. Uniform BIBO stability and uniform BIBO stability with input threshold are studied. A numerical simulation is carried out to show the system's dynamic response, and demonstrate the effectiveness of our theoretical results.
The dissertation investigates the wide class of Epstein zeta-functions in terms of uniform distribution modulo one of the ordinates of their nontrivial zeros. Main results are a proof of a Landau type theorem for all Epstein zeta-functions as well as uniform distribution modulo one for the zero ordinates of all Epstein zeta-functions asscoiated with binary quadratic forms.
In order to unify two major theories of moral judgment, a novel task is employed which combines elements of Kohlberg´s stage theory and of the theory of information integration. In contrast to the format of Kohlberg´s moral judgment interview, a nonverbal and quantitative response which makes low demands on verbal facility was used . Moral informers differing in value, i.e. high and low, are presented. The differences in effect of those two pieces of information should be substantial for a person at that specific moral stage, but small for a person at a different stage. Hence, these differences may diagnose the person's moral stage in the simplest possible way as the two levels of each of the thoughts were about typical content of the four Kohlbergian preconventional and conventional stages. The novel task allowed additionally to measure the influence of another moral concept which was about the non-Kohlbergian moral concept of recompense. After a training phase, pairs of those thoughts were presented to allow for the study of integration and individual differences. German and Korean children, 8, 10, and 12 years in age, judged deserved punishment. The patterns of means, correlations and factor loadings showed that elements of both theories can be unified, but produced unexpected results also. Additive integration of each of the two pairs of moral informers appeared, either with two Kohlbergian moral informers or with another Kohlbergian moral informer in combination with information about recompense. Also cultural independence as well as dependence, developmental changes between 8 and 10 years, and an outstanding moral impact of recompense in size and distinctiveness were observed.
Expanding on a general equilibrium model of offshoring, we analyze the effects of a unilateral emissions tax increase on the environment, income, and inequality. Heterogeneous firms allocate labor across production tasks and emissions abatement, while only the most productive can benefit from lower labor and/or emissions costs abroad and offshore. We find a non-monotonic effect on global emissions, which decline if the initial difference in emissions taxes is small. For a sufficiently large difference, global emissions rise, implying emissions leakage of more than 100%. The underlying driver is a global technique effect: While the emissions intensity of incumbent non-offshoring firms declines, the cleanest firms start offshoring. Moreover, offshoring firms become dirtier, induced by a reduction in the foreign effective emissions tax in general equilibrium. Implementing a BCA prevents emissions leakage, reduces income inequality in the reforming country, but raises inequality across countries.
Unique features of a global human ectoparasite identified through sequencing of the bed bug genome
(2016)
The bed bug, Cimex lectularius, has re-established itself as a ubiquitous human ectoparasite throughout much of the world during the past two decades. This global resurgence is likely linked to increased international travel and commerce in addition to widespread insecticide resistance. Analyses of the C. lectularius sequenced genome (650 Mb) and 14,220 predicted protein-coding genes provide a comprehensive representation of genes that are linked to traumatic insemination, a reduced chemosensory repertoire of genes related to obligate hematophagy, host–symbiont interactions, and several mechanisms of insecticide resistance. In addition, we document the presence of multiple putative lateral gene transfer events. Genome sequencing and annotation establish a solid foundation for future research on mechanisms of insecticide resistance, human–bed bug and symbiont–bed bug associations, and unique features of bed bug biology that contribute to the unprecedented success of C. lectularius as a human ectoparasite.
Merkel cell carcinoma (MCC) is a deadly skin cancer, and about 80% of its cases have been shown to harbor integrated Merkel polyomavirus in the tumor cell genome. Viral oncoproteins expressed in the tumor cells are considered as the oncogenic factors of these virus-positive Merkel cell carcinoma (VP-MCC). In contrast, the molecular pathogenesis of virus-negative MCC (VN-MCC) is less well understood. Using gene expression analysis of MCC cell lines, we found histone methyltransferase PRDM8 to be elevated in VN-MCC. This finding was confirmed by immunohistochemical analysis of MCC tumors, revealing that increased PRDM8 expression in VN-MCC is also associated with increased H3K9 methylation. CRISPR-mediated silencing of PRDM8 in MCC cells further supported the histone methylating role of this protein in VN-MCC. We also identified miR-20a-5p as a negative regulator of PRDM8. Taken together, our findings provide insights into the role of PRDM8 as a histone methyltransferase in VN-MCC tumorigenesis.
The work at hand discusses various universality results for locally univalent and conformal metrics.
In Chapter 2 several interesting approximation results are discussed. Runge-type Theorems for holomorphic and meromorphic locally univalent functions are shown. A well-known local approximation theorem for harmonic functions due to Keldysh is generalized to solutions of the curvature equation.
In Chapter 3 and 4 these approximation theorems are used to establish universality results for locally univalent functions and conformal metrics. In particular locally univalent analogues for well-known universality results due Birkhoff, Seidel & Walsh and Heins are shown.
Universal prevention for non-suicidal self-injury in adolescents is scarce - A systematic review
(2023)
Non-suicidal self-injury (NSSI) during adolescence is a high-risk marker for the development and persistence of mental health problems and has been recognized as a significant public health problem. Whereas targeted prevention has indeed shown to be effective in reducing NSSI and improve mental health problems, access to such programs is limited. By face validity, universal prevention of NSSI seems an ideal starting point for a stepped-care model to circumvent a lack of resources in the medical care system. However, it is yet unclear how effective such approaches are. Here, we provide a summary of existing work on universal prevention of NSSI in adolescents younger than 21 years based on a systematic literature search. We found that only seven studies are available. None of the programs evaluated was found to be effective in reducing the incidence or frequency of NSSI. After providing a comprehensive summary of the existing work, we evaluate the fact that existing work primarily focusses on selected/targeted prevention and on psychoeducational methods. We derive implications for future directions in the field of universal prevention of NSSI.
Universal prevention of nonsuicidal self-injury for children and adolescents – A systematic review –
(2022)
In a synopsis of the current state of research regarding NSSI, there are two key findings of this thesis: Firstly, there is a severe scarcity of studies and currently no evidence base for effective universal prevention of NSSI in youth. Secondly, not only the number but also quality of those few studies found was considered too low to draw wide-ranging conclusions and no meta-analysis could be conducted. This conclusion based – among other factors listed in chapter six – on the application of the EPHPP quality assessment tool (Evans, Lasen et al. 2015), which revealed distinct deficiencies and a weak overall study quality for all seven studies.
Even if the high prevalence of NSSI among adolescents and the importance of this field of research is increasingly emphasized in contemporary literature (Muehlenkamp, Walsh et al. 2010, Wasserman, Carli et al. 2010, Brunner, Kaess et al. 2014, Plener, Schumacher et al. 2015), the shortage of concrete programs addressing the issue is manifest. The potential to tackle NSSI via prevention is underlined in view of the fact that many recent studies prove the high potential of primary prevention regarding NSSI incidences (Evans, Hawton et al. 2005, Fortune, Sinclair et al. 2008).
From the studies included for this review, it can be concluded that most interventions show positive effects in raising awareness, knowledge, understanding of risk factors and help-seeking attitudes among school staff or students, particularly when starting with low knowledge at baseline (Robinson, Gook et al. 2008). Yet, most studies focus on training of gatekeepers and only two programmes address students directly and primarily measure actual NSSI behaviour. This finding highlights the importance of more investigation into concrete NSSI measurement targeting mainly the group of youth.
There is a severe lack of literature on primary prevention with suitable contexts and target groups, while reviews on secondary targeted prevention deliver much more potential in the quantity of research (Kothgassner, Robinson et al. 2020, Kothgassner, Goreis et al. 2021). Until that changes, secondary prevention approaches of NSSI should be relied upon first.
Looking into the future, several considerations may help advance universal approaches to NSSI. Regarding study planning, it is crucial for future research to pursue a thorough background research, examine the feasibility of interventions, and evaluate the appropriateness of study samples chosen. Moreover, research groups are expected to ensure a close observation of participants in cases of adverse events, in order to offer support, but also detect potential deficiencies in the study organisation. Additionally – in accordance with other research in this field (Plener, Brunner et al. 2010) – findings of this review highlight the necessity to expand fundamental research on functions of NSSI and its (neurobiological) mechanism of formation in order to enhance the knowledge of correlations and improve effective preventive approaches. As psychoeducational methods have shown risks of iatrogenic effects (e.g. in patients with eating disorders) (Stice, 2007 #10063), it might be worthwhile to focus on improving emotion regulation in order to strengthen protective factors and improve adolescents’ management of their everyday lives rather than on merely mitigating possible risk factors. Regarding intervention costs, it appears indispensable to include more cost calculations in the study planning of future research. In contrast to therapeutic interventions of NSSI, which are usually conducted in an in-patient setting and entail high measurable expenses as compared to preventive interventions, preventive approaches may in case of success result in a reduction of clinical presentation (O’Connell, Boat et al. 2009).
A promising outlook is entailed by study protocol presenting a skills-based universal prevention program of NSSI “DUDE”, a cluster randomized controlled trial scheduled for 16 German schools with a total of 3.200 adolescents (Buerger, Emser et al. 2022). The program is tailored to decrease the incidence of NSSI and avert potential and associated long-term consequences like suicidality among adolescents. It is aimed to provide easy access for adolescents due to its implementation during lesson time at school and is declared cost-effective. Furthermore, DUDE is a promising approach to effective NSSI prevention, as it is intended to improve mental health through the pathway of emotion regulation. It remains to await the implementation of the protocol, which is currently delayed due to the SARS-CoV-19 pandemic.
In sum, initial research is promising and suggests that the approach to tackle NSSI via prevention is meaningful. Yet, high-quality studies on the development and evaluation of universal NSSI prevention in adolescents are urgently needed.
The starting point of the thesis is the {\it universality} property of the Riemann Zeta-function $\zeta(s)$
which was proved by Voronin in 1975:
{\it Given a positive number $\varepsilon>0$ and an analytic non-vanishing function $f$ defined on a compact subset $\mathcal{K}$ of the strip $\left\{s\in\mathbb{C}:1/2 < \Re s< 1\right\}$ with connected complement, there exists a real number $\tau$ such that
\begin{align}\label{continuous}
\max\limits_{s\in \mathcal{K}}|\zeta(s+i\tau)-f(s)|<\varepsilon.
\end{align}
}
In 1980, Reich proved a discrete analogue of Voronin’s theorem, also known as {\it discrete universality theorem} for $\zeta(s)$:
{\it If $\mathcal{K}$, $f$ and $\varepsilon$ are as before, then
\begin{align}\label{discretee}
\liminf\limits_{N\to\infty}\dfrac{1}{N}\sharp\left\{1\leq n\leq N:\max\limits_{s\in \mathcal{K}}|\zeta(s+i\Delta n)-f(s)|<\varepsilon\right\}>0,
\end{align}
where $\Delta$ is an arbitrary but fixed positive number.
}
We aim at developing a theory which can be applied to prove the majority of all so far existing discrete universality theorems in the case of Dirichlet $L$-functions $L(s,\chi)$ and Hurwitz zeta-functions $\zeta(s;\alpha)$,
where $\chi$ is a Dirichlet character and $\alpha\in(0,1]$, respectively.
Both of the aforementioned classes of functions are generalizations of $\zeta(s)$, since $\zeta(s)=L(s,\chi_0)=\zeta(s;1)$, where $\chi_0$ is the principal Dirichlet character mod 1.
Amongst others, we prove statement (2) where instead of $\zeta(s)$ we have $L(s,\chi)$ for some Dirichlet character $\chi$ or $\zeta(s;\alpha)$ for some transcendental or rational number $\alpha\in(0,1]$, and instead of $(\Delta n)_{n\in\mathbb{N}}$ we can have:
\begin{enumerate}
\item \textit{Beatty sequences,}
\item \textit{sequences of ordinates of $c$-points of zeta-functions from the Selberg class,}
\item \textit{sequences which are generated by polynomials.}
\end{enumerate}
In all the preceding cases, the notion of {\it uniformly distributed sequences} plays an important role and we draw attention to it wherever we can.
Moreover, for the case of polynomials, we employ more advanced techniques from Analytic Number Theory such as bounds of exponential sums and zero-density estimates for Dirichlet $L$-functions.
This will allow us to prove the existence of discrete second moments of $L(s,\chi)$ and $\zeta(s;\alpha)$ on the left of the vertical line $1+i\mathbb{R}$, with respect to polynomials.
In the case of the Hurwitz Zeta-function $\zeta(s;\alpha)$, where $\alpha$ is transcendental or rational but not equal to $1/2$ or 1, the target function $f$ in (1) or (2), where $\zeta(\cdot)$ is replaced by $\zeta(\cdot;\alpha)$, is also allowed to have zeros.
Until recently there was no result regarding the universality of $\zeta(s;\alpha)$ in the literature whenever $\alpha$ is an algebraic irrational.
In the second half of the thesis, we prove that a weak version of statement \eqref{continuous} for $\zeta(s;\alpha)$ holds for all but finitely many algebraic irrational $\alpha$ in $[A,1]$, where $A\in(0,1]$ is an arbitrary but fixed real number.
Lastly, we prove that the ordinary Dirichlet series
$\zeta(s;f)=\sum_{n\geq1}f(n)n^{-s}$ and $\zeta_\alpha(s)=\sum_{n\geq1}\lfloor P(\alpha n+\beta)\rfloor^{-s}$
are hypertranscendental, where $f:\mathbb{N}\to\mathbb{C}$ is a {\it Besicovitch almost periodic arithmetical function}, $\alpha,\beta>0$ are such that $\lfloor\alpha+\beta\rfloor>1$ and $P\in\mathbb{Z}[X]$ is such that $P(\mathbb{N})\subseteq\mathbb{N}$.
Background: Acute myeloid leukemia (AML) is both more common and with more biologically aggressive phenotype in the elderly. Allogenic stem cell transplantation (allo-SCT) is the best treatment option in fit patients. Either HLA-matched unrelated donor (MUD) or haploidentical (Haplo) donor are possible alternative for patients in need. Methods: We retrospectively compared non-T-cell-depleted Haplo (n = 250) to 10/10 MUD (n = 2589) in AML patients >= 60 years. Results: Median follow-up was 23 months. Disease status at transplant differs significantly between the two groups (p < 10(-4)). Reduced intensity conditioning (RIC) was administrated to 73 and 77% of Haplo and MUD, respectively (p = 0.23). Stem cell source was the bone marrow (BM) in 52% of the Haplo and 6% of MUD (p < 10(-4)). Anti-thymocyte globulin (ATG) was most frequently used in MUD (p < 10(-4)) while post-Tx cyclophosphamide (PT-Cy) was given in 62% of Haplo. Engraftment was achieved in 90% of the Haplo vs 97% of MUD (p < 10(-4)). In multivariate analysis, no significant difference was found between Haplo and MUD for acute (a) graft versus host disease (GVHD) grade II-IV, relapse incidence (RI), non-relapse mortality (NRM), leukemia free survival (LFS), graft-versus-host-free-relapse free survival (GRFS), and overall survival (OS). Extensive chronic (c) GVHD was significantly higher for MUD as compared to Haplo (HR 2, p = 0.01, 95% CI 1.17-3.47). A propensity score analysis confirmed the higher risk of extensive cGVHD for MUD without differences for other outcomes. Conclusions: Allo-SCT from both Haplo and MUD are valid option for AML patients >= 60 years of age with similar results. Transplantation from MUD was associated with higher extensive cGVHD. Our findings suggest that Haplo is a suitable and attractive graft source for patients >= 60 with AML in need of allo-SCT.
Aims
Chronic heart failure (CHF) can be caused by autoantibodies stimulating the heart via binding to first and/or second extracellular loops of cardiac β1-adrenoceptors. Allosteric receptor activation depends on conformational features of the autoantibody binding site. Elucidating these features will pave the way for the development of specific diagnostics and therapeutics. Our aim was (i) to fine-map the conformational epitope within the second extracellular loop of the human β\(_1\)-adrenoceptor (β1ECII) that is targeted by stimulating β\(_1\)-receptor (auto)antibodies and (ii) to generate competitive cyclopeptide inhibitors of allosteric receptor activation, which faithfully conserve the conformational auto-epitope.
Methods and results
Non-conserved amino acids within the β\(_1\)EC\(_{II}\) loop (compared with the amino acids constituting the ECII loop of the β\(_2\)-adrenoceptor) were one by one replaced with alanine; potential intra-loop disulfide bridges were probed by cysteine–serine exchanges. Effects on antibody binding and allosteric receptor activation were assessed (i) by (auto)antibody neutralization using cyclopeptides mimicking β1ECII ± the above replacements, and (ii) by (auto)antibody stimulation of human β\(_1\)-adrenoceptors bearing corresponding point mutations. With the use of stimulating β\(_1\)-receptor (auto)antibodies raised in mice, rats, or rabbits and isolated from exemplary dilated cardiomyopathy patients, our series of experiments unmasked two features of the β\(_1\)EC\(_{II}\) loop essential for (auto)antibody binding and allosteric receptor activation: (i) the NDPK\(^{211–214}\) motif and (ii) the intra-loop disulfide bond C\(^{209}\)↔C\(^{215}\). Of note, aberrant intra-loop disulfide bond C\(^{209}\)↔C\(^{216}\) almost fully disrupted the functional auto-epitope in cyclopeptides.
Conclusions
The conformational auto-epitope targeted by cardio-pathogenic β\(_1\)-receptor autoantibodies is faithfully conserved in cyclopeptide homologues of the β\(_1\)EC\(_{II}\) loop bearing the NDPK\(^{211–214}\) motif and the C\(^{209}\)↔C\(^{215}\) bridge while lacking cysteine C216. Such molecules provide promising tools for novel diagnostic and therapeutic approaches in β\(_1\)-autoantibodypositive CHF.
Cervical dystonia (CD) is a movement disorder which affects daily living of many patients. In clinical practice, several unmet treatment needs remain open. This article focuses on the four main aspects of treatment. We describe existing and emerging treatment approaches for CD, including botulinum toxin injections, surgical therapy, management of non-motor symptoms, and rehabilitation strategies. The unsolved issues regarding each of these treatments are identified and discussed, and possible future approaches and research lines are proposed.
Forward Collision Alarms (FCA) intend to signal hazardous traffic situations and the need for an immediate corrective driver response. However, data of naturalistic driving studies revealed that approximately the half of all alarms activated by conventional FCA systems represented unnecessary alarms. In these situations, the alarm activation was correct according to the implemented algorithm, whereas the alarms led to no or only minimal driver responses. Psychological research can make an important contribution to understand drivers’ needs when interacting with driver assistance systems.
The overarching objective of this thesis was to gain a systematic understanding of psychological factors and processes that influence drivers’ perceived need for assistance in potential collision situations. To elucidate under which conditions drivers perceive alarms as unnecessary, a theoretical framework of drivers’ subjective alarm evaluation was developed. A further goal was to investigate the impact of unnecessary alarms on drivers’ responses and acceptance. Four driving simulator studies were carried out to examine the outlined research questions.
In line with the hypotheses derived from the theoretical framework, the results suggest that drivers’ perceived need for assistance is determined by their retrospective subjective hazard perception. While predictions of conventional FCA systems are exclusively based on physical measurements resulting in a time to collision, human drivers additionally consider their own manoeuvre intentions and those attributed to other road users to anticipate the further course of a potentially critical situation. When drivers anticipate a dissolving outcome of a potential conflict, they perceive the situation as less hazardous than the system. Based on this discrepancy, the system would activate an alarm, while drivers’ perceived need for assistance is low. To sum up, the described factors and processes cause drivers to perceive certain alarms as unnecessary. Although drivers accept unnecessary alarms less than useful alarms, unnecessary alarms do not reduce their overall system acceptance. While unnecessary alarms cause moderate driver responses in the short term, the intensity of responses decrease with multiple exposures to unnecessary alarms. However, overall, effects of unnecessary alarms on drivers’ alarm responses and acceptance seem to be rather uncritical.
This thesis provides insights into human factors that explain when FCAs are perceived as unnecessary. These factors might contribute to design FCA systems tailored to drivers’ needs.
Alien limb phenomenon is a rare syndrome associated with a feeling of non-belonging and disowning toward one's limb. In contrast, anarchic limb phenomenon leads to involuntary but goal-directed movements. Alien/anarchic limb phenomena are frequent in corticobasal syndrome (CBS), an atypical parkinsonian syndrome characterized by rigidity, akinesia, dystonia, cortical sensory deficit, and apraxia. The structure function relationship of alien/anarchic limb was investigated in multi centric structural magnetic resonance imaging (MRI) data. Whole-group and single subject comparisons were made in 25 CBS and eight CBS-alien/anarchic limb patients versus controls. Support vector machine was used to see if CBS with and without alien/anarchic limb could be distinguished by structural MRI patterns. Whole-group comparison of CBS versus controls revealed asymmetric frontotemporal atrophy. CBS with alien/anarchic limb syndrome versus controls showed frontoparietal atrophy including the supplementary motor area contralateral to the side of the affected limb. Exploratory analysis identified frontotemporal regions encompassing the pre-/and postcentral gyrus as compromised in CBS with alien limb syndrome. Classification of CBS patients yielded accuracies of 79%. CBS-alien/anarchic limb syndrome was differentiated from CBS patients with an accuracy of 81%. Predictive differences were found in the cingulate gyrus spreading to frontomedian cortex, postcentral gyrus, and temporoparietoocipital regions. We present the first MRI-based group analysis on CBS-alien/anarchic limb. Results pave the way for individual clinical syndrome prediction and allow understanding the underlying neurocognitive architecture. (C) 2019 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Unraveling the connection between fibroblast growth factor and bone morphogenetic protein signaling
(2018)
Ontogeny of higher organisms as well the regulation of tissue homeostasis in adult individuals requires a fine-balanced interplay of regulating factors that individually trigger the fate of particular cells to either stay undifferentiated or to differentiate towards distinct tissue specific lineages. In some cases, these factors act synergistically to promote certain cellular responses, whereas in other tissues the same factors antagonize each other. However, the molecular basis of this obvious dual signaling activity is still only poorly understood. Bone morphogenetic proteins (BMPs) and fibroblast growth factors (FGFs) are two major signal protein families that have a lot in common: They are both highly preserved between different species, involved in essential cellular functions, and their ligands vastly outnumber their receptors, making extensive signal regulation necessary. In this review we discuss where and how BMP and FGF signaling cross paths. The compiled data reflect that both factors synchronously act in many tissues, and that antagonism and synergism both exist in a context-dependent manner. Therefore, by challenging a generalization of the connection between these two pathways a new chapter in BMP FGF signaling research will be introduced.
Biological systems are in dynamic interaction. Many responses reside in the core concepts of biological systems interplay (competition and cooperation). In infection situation, the competition between a bacterial system and a host is shaped by many stressors at spatial and temporal determinants. Reactive chemical species are universal stressors against all biological systems since they potentially damage the basic requirements of these systems (nucleic acids, proteins, carbohydrates, and lipids). Either produced endogenously or exogenously, reactive chemical species affect the survival of pathogens including the gram-positive
Staphylococcus aureus (S. aureus). Therefore, bacteria developed strategies to overcome the toxicity of reactive species.
S. aureus is a widely found opportunistic pathogen. In its niche, S. aureus is in permanent contact with surrounding microbes and host factors. Deciphering the deterministic factors
in these interactions could facilitate pinpointing novel bacterial targets. Identifying
the aforementioned targets is crucial to develop new strategies not only to kill the pathogenic organisms but also to enhance the normal flora to minimize the pathogenicity and virulence of potential pathogens. Moreover, targeting S. aureus stress response can be used
to overcome bacterial resistance against host-derived factors. In this study, I identify a novel
S. aureus stress response factor against reactive electrophilic, oxygen, and hypochlorite species to better understand its resilience as a pathogen.
Although bacterial stress response is an active research field, gene function is a current bottleneck in characterizing the understudied bacterial strategies to mediate stress conditions. I aimed at understanding the function of a novel protein family integrated
in many defense systems of several biological systems.
In bacteria, fungi, and plants, old yellow enzymes (OYEs) are widely found. Since the first isolation of the yellow flavoprotein, OYEs are used as biocatalysts for decades to reduce activated C=C bonds in α,β-unsaturated carbonyl compounds. The promiscuity
of the enzymatic catalysis is advantageous for industrial applications.
However, the physiological function of OYEs, especially in bacteria, is still puzzling.
Moreover, the relevance of the OYEs in infection conditions remained enigmatic.
Here, I show that there are two groups of OYEs (OYE flavin oxidoreductase, OfrA and OfrB) that are encoded in staphylococci and some firmicutes. OfrA (SAUSA300_0859) is more conserved than OfrB (SAUSA300_0322) in staphylococci and is a part of the staphylococcal core genome.
A reporter system was established to report for ofrA in S. aureus background.
The results showed that ofrA is induced under electrophilic, oxidative, and hypochlorite stress. OfrA protects S. aureus against quinone, methylglyoxal, hydrogen peroxide,
and hypochlorite stress. Additionally, the results provide evidence that OfrA supports
thiol-dependent redox homeostasis. At the host-pathogen interface, OfrA promotes S. aureus fitness in murine macrophage cell line. In whole human blood, OfrA is involved in S. aureus survival indicating a potential clinical relevance to bacteraemia.
In addition, ofrA mutation affects the production of the virulence factor staphyloxanthin via the upper mevalonate pathway. In summary, decoding OfrA function and its proposed mechanism of action in S. aureus shed the light on a conserved stress response within multiple organisms.
Usher syndrome, the most prevalent cause of combined hereditary vision and hearing impairment, is clinically and genetically heterogeneous. Moreover, several conditions with phenotypes overlapping Usher syndrome have been described. This makes the molecular diagnosis of hereditary deaf-blindness challenging. Here, we performed exome sequencing and analysis on 7 Mexican and 52 Iranian probands with combined retinal degeneration and hearing impairment (without intellectual disability). Clinical assessment involved ophthalmological examination and hearing loss questionnaire. Usher syndrome, most frequently due to biallelic variants in MYO7A (USH1B in 16 probands), USH2A (17 probands), and ADGRV1 (USH2C in 7 probands), was diagnosed in 44 of 59 (75%) unrelated probands. Almost half of the identified variants were novel. Nine of 59 (15%) probands displayed other genetic entities with dual sensory impairment, including Alström syndrome (3 patients), cone-rod dystrophy and hearing loss 1 (2 probands), and Heimler syndrome (1 patient). Unexpected findings included one proband each with Scheie syndrome, coenzyme Q10 deficiency, and pseudoxanthoma elasticum. In four probands, including three Usher cases, dual sensory impairment was either modified/aggravated or caused by variants in distinct genes associated with retinal degeneration and/or hearing loss. The overall diagnostic yield of whole exome analysis in our deaf-blind cohort was 92%. Two (3%) probands were partially solved and only 3 (5%) remained without any molecular diagnosis. In many cases, the molecular diagnosis is important to guide genetic counseling, to support prognostic outcomes and decisions with currently available and evolving treatment modalities.
G-protein-coupled receptors (GPCRs) are hypothesized to possess molecular mobility over a wide temporal range. Until now the temporal range has not been fully accessible due to the crucially limited temporal range of available methods. This in turn, may lead relevant dynamic constants to remain masked. Here, we expand this dynamic range by combining fluorescent techniques using a spot confocal setup. We decipher mobility constants of β\(_{2}\)-adrenergic receptor over a wide time range (nanosecond to second). Particularly, a translational mobility (10 µm\(^{2}\)/s), one order of magnitude faster than membrane associated lateral mobility that explains membrane protein turnover and suggests a wider picture of the GPCR availability on the plasma membrane. And a so far elusive rotational mobility (1-200 µs) which depicts a previously overlooked dynamic component that, despite all complexity, behaves largely as predicted by the Saffman-Delbrück model.
Cyclic diboranes(4) based on a chelating monoanionic, benzylphosphine linker were prepared by boron-silicon exchange between arylsilanes and B\(_2\)Br\(_4\). Coordination of Lewis bases to the remaining sp\(^2\) boron atom yielded unsymmetrical sp\(^3\)-sp\(^3\) diboranes, which were reduced with KC\(_8\) to their corresponding trans-diborenes. These compounds were studied by a combination of spectroscopic methods, X-ray diffraction and DFT calculations. PMe\(_3\)-stabilized diborene 6 was found to undergo thermal rearrangement to gem- diborene 8. DFT calculations on 8 reveal a polar boron-boron bond, and indicate that the compound is best described as a borylborylene.
Carbon-13 shieldings and one-bond \(^{13}\)C-H coupling constants of bicydo[2.1.1]hexane, bicydo[2.l.l]hex- 2-ene, tricydo[3.1.1.0\(^{2.4}\)]heptane and benzvalene are presented and compared. to the data of related. compounds. H a bicydo[3.1.0]hexane system is part of a rigid skeleton, the cydopropane ring exerts spedfk: 'Y substituent eflects of two ldnds. In the case of the bicyclobexane boat form an upfield shift of the C-3 signal is observed and in tbe esse of the chair form a downfield shift of 15-20 ppm. Compared to the corresponding cydopentanes the double bond in strained cydopentenes causes downfield shifts of the C-4 absorption. 1bis eftect increases witb increasing strain, reaching 8 45.9 ppm maximum in benzvalene. Hence it is tbe only known bicydo[l.l.O]butane baving 8 reversed order of carbon shieldings. The downfield shifts are e:xplained by means of simple orbital interaction schemes.
Background: Myofibrillar myopathies (MFM) are a group of phenotypically and genetically heterogeneous neuromuscular disorders, which are characterized by protein aggregations in muscle fibres and can be associated with multisystemic involvement.
Methods: We screened a large cohort of 38 index patients with MFM for mutations in the nine thus far known causative genes using Sanger and next generation sequencing (NGS). We studied the clinical and histopathological characteristics in 38 index patients and five additional relatives (n = 43) and particularly focused on the associated multisystemic symptoms.
Results: We identified 14 heterozygous mutations (diagnostic yield of 37%), among them the novel p. Pro209Gln mutation in the BAG3 gene, which was associated with onset in adulthood, a mild phenotype and an axonal sensorimotor polyneuropathy, in the absence of giant axons at the nerve biopsy. We revealed several novel clinical phenotypes and unusual multisystemic presentations with previously described mutations: hearing impairment with a FLNC mutation, dysphonia with a mutation in DES and the first patient with a FLNC mutation presenting respiratory insufficiency as the initial symptom. Moreover, we described for the first time respiratory insufficiency occurring in a patient with the p. Gly154Ser mutation in CRYAB. Interestingly, we detected a polyneuropathy in 28% of the MFM patients, including a BAG3 and a MYOT case, and hearing impairment in 13%, including one patient with a FLNC mutation and two with mutations in the DES gene. In four index patients with a mutation in one of the MFM genes, typical histological findings were only identified at the ultrastructural level (29%).
Conclusions: We conclude that extraskeletal symptoms frequently occur in MFM, particularly cardiac and respiratory involvement, polyneuropathy and/or deafness. BAG3 mutations should be considered even in cases with a mild phenotype or an adult onset. We identified a genetic defect in one of the known genes in less than half of the MFM patients, indicating that more causative genes are still to be found. Next generation sequencing techniques should be helpful in achieving this aim.
Crystals of the R, S diastereoisomer of [Cp(CO)\(_2\)-FeSiCH\(_3\)F]\(_2\)O are monoclinic, space group ndc (No. 14), with a = 846.0(3) [836.4(1»), b = 768.0(3) [757.1(1»), c = 1548.5(4) [1522.3(2)] pm, {3 = 97.34(3t [97.47(3t] at 300 K [120 K] with Z = 2. Even at 120 K the Si-O-Si fragment is found to be strictly linear due to crystallographically imposed symmetry. To explain the unusual electron distribution derived from the X-ray data collected, several types of possible disorders are discussed, none of which leads to a satisfying explanation. Retaining the Ci symmetry (linear Si-O-Si fragment in the final model) the important bond lengths are Fe-Si 226.7(1) [226.5(1)] pm, Si-F 160.9(2) [161.8(2)] pm, Si-O 160.3(1) [161.1(1)] pm, Si-C 185.0(3) [185.6(3)] pm. The electronic features of this compound were probed via molecular orbital calculations of the extended Hiickel type. It was found that the lone pairs on the siloxane oxygen were tipped away from cylindrical symmetry. The tipping was directed toward the fluorine substituents on the silicon atoms and away from the CpFe(CO)\(_2\) units. A pertubational approach was utilized to rationalize this effect.
The worldwide demand for food has been increasing due to the rapidly growing global population, and agricultural lands have increased in extent to produce more food crops. The pattern of cropland varies among different regions depending on the traditional knowledge of farmers and availability of uncultivated land. Satellite images can be used to map cropland in open areas but have limitations for detecting undergrowth inside forests. Classification results are often biased and need to be supplemented with field observations. Undercover cropland inside forests in the Bale Mountains of Ethiopia was assessed using field observed percentage cover of land use/land cover classes, and topographic and location parameters. The most influential factors were identified using Boosted Regression Trees and used to map undercover cropland area. Elevation, slope, easterly aspect, distance to settlements, and distance to national park were found to be the most influential factors determining undercover cropland area. When there is very high demand for growing food crops, constrained under restricted rights for clearing forest, cultivation could take place within forests as an undercover. Further research on the impact of undercover cropland on ecosystem services and challenges in sustainable management is thus essential.
Background: With the availability of T-cell-directed therapy and next-generation compounds of established classes of drugs, the treatment of relapsed/refractory (r/r) myeloma is getting more complex. However, treatment options in practice are limited by availability, approval, and patient comorbidity. The aim of this article is to provide a practical approach toward the choice of treatment for r/r myeloma patients. Summary: Regarding market authorization and current guidelines, at least in Germany, most patients nowadays will have received a doublet or triplet combination as first-line therapy containing a proteasome inhibitor and an immunomodulatory drug, mostly lenalidomide. We focus on the treatment options for patients that are ineligible for (another) stem cell transplantation. We will review treatment options for relapse after first- or second-line therapy and beyond third-line. Key Messages: There is promising data supporting the efficacy and safety of triplet combinations containing anti-CD38-monoclonal antibodies (anti-CD38 mAbs) at first or second relapse in combination with next-generation compounds. For the treatment beyond third-line, comparative studies are scarce but some promising compounds are available via conditional authorization, and there is more to come in the future. We will present some early phase trials featuring promising results.
Fungi of the order Mucorales colonize all kinds of wet, organic materials and represent a permanent part of the human environment. They are economically important as fermenting agents of soybean products and producers of enzymes, but also as plant parasites and spoilage organisms. Several taxa cause life-threatening infections, predominantly in patients with impaired immunity. The order Mucorales has now been assigned to the phylum Mucoromycota and is comprised of 261 species in 55 genera. Of these accepted species, 38 have been reported to cause infections in humans, as a clinical entity known as mucormycosis. Due to molecular phylogenetic studies, the taxonomy of the order has changed widely during the last years. Characteristics such as homothallism, the shape of the suspensors, or the formation of sporangiola are shown to be not taxonomically relevant. Several genera including Absidia, Backusella, Circinella, Mucor, and Rhizomucor have been amended and their revisions are summarized in this review. Medically important species that have been affected by recent changes include Lichtheimia corymbifera, Mucor circinelloides, and Rhizopus microsporus. The species concept of Rhizopus arrhizus (syn. R. oryzae) is still a matter of debate. Currently, species identification of the Mucorales is best performed by sequencing of the internal transcribed spacer (ITS) region. Ecologically, the Mucorales represent a diverse group but for the majority of taxa, the ecological role and the geographic distribution remain unknown. Understanding the biology of these opportunistic fungal pathogens is a prerequisite for the prevention of infections, and, consequently, studies on the ecology of the Mucorales are urgently needed.
Introduction The fast, precise, and accurate measurement of the new generation of oral anticoagulants such as dabigatran and rivaroxaban in patients' plasma my provide important information in different clinical circumstances such as in the case of suspicion of overdose, when patients switch from existing oral anticoagulant, in patients with hepatic or renal impairment, by concomitant use of interaction drugs, or to assess anticoagulant concentration in patients' blood before major surgery. Methods Here, we describe a quick and precise method to measure the coagulation inhibitors dabigatran and rivaroxaban using ultra-performance liquid chromatography electrospray ionization-tandem mass spectrometry in multiple reactions monitoring (MRM) mode (UPLC-MRM MS). Internal standards (ISs) were added to the sample and after protein precipitation; the sample was separated on a reverse phase column. After ionization of the analytes the ions were detected using electrospray ionization-tandem mass spectrometry. Run time was 2.5 minutes per injection. Ion suppression was characterized by means of post-column infusion. Results The calibration curves of dabigatran and rivaroxaban were linear over the working range between 0.8 and 800 mu g/L (r > 0.99). Limits of detection (LOD) in the plasma matrix were 0.21 mu g/L for dabigatran and 0.34 mu g/L for rivaroxaban, and lower limits of quantification (LLOQ) in the plasma matrix were 0.46 mu g/L for dabigatran and 0.54 mu g/L for rivaroxaban. The intraassay coefficients of variation (CVs) for dabigatran and rivaroxaban were < 4% and 6%; respectively, the interassay CVs were < 6% for dabigatran and < 9% for rivaroxaban. Inaccuracy was < 5% for both substances. The mean recovery was 104.5% (range 83.8-113.0%) for dabigatran and 87.0%(range 73.6-105.4%) for rivaroxaban. No significant ion suppressions were detected at the elution times of dabigatran or rivaroxaban. Both coagulation inhibitors were stable in citrate plasma at -20 degrees C, 4 degrees C and even at RT for at least one week. A method comparison between our UPLC-MRM MS method, the commercially available automated Direct Thrombin Inhibitor assay (DTI assay) for dabigatran measurement from CoaChrom Diagnostica, as well as the automated anti-Xa assay for rivaroxaban measurement from Chromogenix both performed by ACL-TOP showed a high degree of correlation. However, UPLC-MRM MS measurement of dabigatran and rivaroxaban has a much better selectivity than classical functional assays measuring activities of various coagulation factors which are susceptible to interference by other coagulant drugs. Conclusions Overall, we developed and validated a sensitive and specific UPLC-MRM MS assay for the quick and specific measurement of dabigatran and rivaroxaban in human plasma.
Uplink vs. Downlink: Machine Learning-Based Quality Prediction for HTTP Adaptive Video Streaming
(2021)
Streaming video is responsible for the bulk of Internet traffic these days. For this reason, Internet providers and network operators try to make predictions and assessments about the streaming quality for an end user. Current monitoring solutions are based on a variety of different machine learning approaches. The challenge for providers and operators nowadays is that existing approaches require large amounts of data. In this work, the most relevant quality of experience metrics, i.e., the initial playback delay, the video streaming quality, video quality changes, and video rebuffering events, are examined using a voluminous data set of more than 13,000 YouTube video streaming runs that were collected with the native YouTube mobile app. Three Machine Learning models are developed and compared to estimate playback behavior based on uplink request information. The main focus has been on developing a lightweight approach using as few features and as little data as possible, while maintaining state-of-the-art performance.
A 42 m drilling was pertormed in the depresalon of Bilma, Xawar, NE-Niger. The sediment and pollen records show that after an initial deposition of dune sands there were repeated lake phases which terminated by desiccation and consolidation of spring mounds. The pollen record indicates a continuous presence of savanna vegetation. The record probably covers the period between the Upper Pleistocene and the Late Holocene. The climate was characterised by a monssonal summer rain regime giving effective rain fall of about 450-500 mm per year. Groundwater recharge was possible but estimates of the amount of water resources are difficult because of the karstic system of the escarpment and the nearly unknown hydrogeological situation.
The expression of intercellular adhesion molecule 1 (ICAM-1) was studied in rat focal ischemic cortex. A significant increase in ICAM-1 mRNA expression in the ischemic cortex over Ievels in contralateral (nonischemic) site was observed by means of Northern blot analysis following either permanent or temporary occlusion with reperfusion of the middle cerebral artery (PMCAO or MCAO with reperfusion) in spontaneously hypertensive rats. In the ischemic cortex, Ievels of ICAM-1 mRNA increased significantly at 3 h (2.6-fold, n = 3, P < 0.05), peaked at 6 to 12 h (6.0-fold, P < 0.01) and remained elevated up to 5 days (2.5-fold, P < 0.05) after PMCAO. The profile of ICAM-1 mRNA expression in the ischemic cortex following MCAO with reperfusion was similar to that following PMCAO, except that ICAM-1 mRNA was significantly increased as early as 1 h (6.3-fold, n = 3, P < 0.05) and then gradually reached a peak at 12 h (12-fold, P < 0.01) after reperfusion. ICAM-1 mRNA expression in ischemic cortex following PMCAO was significantly greater in hypertensive rats than in two normotensive rat strains. Immunostaining using anti-ICAM-1 antiborlies indicated that upregulated ICAM-1 expressionwas localized to endotheIial cells of intraparenchymal blood vessels in the ischemic but not contralateral cortex. The data suggest that an upregulation of ICAM-1 mRNA and protein on brain capillary endothelium may play an important rote in leukocyte migration into ischemic brain tissue.
This paper examines situations where two vertically integrated firms consider supplying an input to an independent downstream competitor via privately observed contracts. We identify equilibria where competition in the upstream market emerges—the downstream competitor gets supplied—as well as when the downstream firm does not receive the input and is excluded from the market. The likelihood of the outcome in which the downstream firm does not get supplied depends not only on demand parameters, but also on contractual flexibility and observability. We show that when contracts are unobservable, downstream entry will occur less often. Furthermore, our results suggest that permitting contracts that enable the contracting parties to coordinate their behavior in the downstream market may improve welfare by increasing the likelihood that the downstream firm is supplied.
Urban areas are population, culture and infrastructure concentration points. Electricity blackouts or interruptions of water supply severely affect people when happening unexpected and at large scale. Interruptions of such infrastructure supply services alone have the potential to trigger crises. But when happening in concert with or as a secondary effect of an earthquake, for example, the crisis situation is often aggravated. This is the case for any country, but it has been observed that even highly industrialised
countries face severe risks when their degree of acquired dependency on services of what is termed Critical Infrastructure results in even bigger losses when occurring unexpectedly in a setting that usually has high reliability of services.
Increasing human land use for agriculture and housing leads to the loss of natural habitat and to widespread declines in wild bees. Bee foraging dynamics and fitness depend on the availability of resources in the surrounding landscape, but how precisely landscape related resource differences affect bee foraging patterns remains unclear. To investigate how landscape and its interaction with season and weather drive foraging and resource intake in social bees, we experimentally compared foraging activity, the allocation of foragers to different resources (pollen, nectar, and resin) and overall resource intake in the Australian stingless bee Tetragonula carbonaria (Apidae, Meliponini). Bee colonies were monitored in different seasons over two years. We compared foraging patterns and resource intake between the bees' natural habitat (forests) and two landscapes differently altered by humans (suburban gardens and agricultural macadamia plantations). We found foraging activity as well as pollen and nectar forager numbers to be highest in suburban gardens, intermediate in forests and low in plantations. Foraging patterns further differed between seasons, but seasonal variations strongly differed between landscapes. Sugar and pollen intake was low in plantations, but contrary with our predictions, it was even higher in gardens than in forests. In contrast, resin intake was similar across landscapes. Consequently, differences in resource availability between natural and altered landscapes strongly affect foraging patterns and thus resource intake in social bees. While agricultural monocultures largely reduce foraging success, suburban gardens can increase resource intake well above rates found in natural habitats of bees, indicating that human activities can both decrease and increase the availability of resources in a landscape and thus reduce or enhance bee fitness.
Background:
Ureaplasma species have been associated with chorioamnionitis and preterm birth and have been implicated in the pathogenesis of neonatal short and long-term morbidity. However, being mostly commensal bacteria, controversy remains on the pro-inflammatory capacity of Ureaplasma. Discussions are ongoing on the incidence and impact of prenatal, perinatal, and postnatal infection. The present study addressed the impact of Ureaplasma isolates on monocyte-driven inflammation.
Methods:
Cord blood monocytes of term neonates and adult monocytes, either native or LPS-primed, were cultured with Ureaplasma urealyticum (U. urealyticum) serovar 8 (Uu8) and Ureaplasma parvum serovar 3 (Up3). Using qRT-PCR, cytokine flow cytometry, and multi-analyte immunoassay, we assessed mRNA and protein expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-8, IL-12p40, IL-10, and IL-1 receptor antagonist (IL-1ra) as well as Toll-like receptor (TLR) 2 and TLR4.
Results:
Uu8 and Up3 induced mRNA expression and protein release of TNF-α, IL-1β and IL-8 in term neonatal and adult monocytes (p < 0.01 and p < 0.05). Intracellular protein expression of TNF-α, IL-1β and IL-8 in Ureaplasma-stimulated cells paralleled those results. Ureaplasma-induced cytokine levels did not significantly differ from LPS-mediated levels except for lower intracellular IL-1β in adult monocytes (Uu8: p < 0.05). Remarkably, ureaplasmas did not induce IL-12p40 response and promoted lower amounts of anti-inflammatory IL-10 and IL-1ra than LPS, provoking a cytokine imbalance more in favor of pro-inflammation (IL-1β/IL-10, IL-8/IL-10 and IL-8/IL-1ra: p < 0.01, vs. LPS). In contrast to LPS, both isolates induced TLR2 mRNA in neonatal and adult cells (p < 0.001 and p < 0.05) and suppressed TLR4 mRNA in adult monocytes (p < 0.05). Upon co-stimulation, Uu8 and Up3 inhibited LPS-induced intracellular IL-1β (p < 0.001 and p < 0.05) and IL-8 in adult monocytes (p < 0.01), while LPS-induced neonatal cytokines were maintained or aggravated (p < 0.05).
Conclusion:
Our data demonstrate a considerable pro-inflammatory capacity of Ureaplasma isolates in human monocytes. Stimulating pro-inflammatory cytokine responses while hardly inducing immunomodulatory and anti-inflammatory cytokines, ureaplasmas might push monocyte immune responses toward pro-inflammation. Inhibition of LPS-induced cytokines in adult monocytes in contrast to sustained inflammation in term neonatal monocytes indicates a differential modulation of host immune responses to a second stimulus. Modification of TLR2 and TLR4 expression may shape host susceptibility to inflammation.
Ureaplasma species are common colonizers of the adult genitourinary tract and often considered as low-virulence commensals. Intraamniotic Ureaplasma infections, however, facilitate chorioamnionitis and preterm birth, and cases of Ureaplasma-induced neonatal sepsis, pneumonia, and meningitis raise a growing awareness of their clinical relevance. In vitro studies are scarce but demonstrate distinct Ureaplasma-driven impacts on immune mechanisms. The current study addressed cytokine and chemokine responses upon exposure of native or lipopolysaccharide (LPS) co-stimulated human brain microvascular endothelial cells (HBMEC) to Ureaplasma urealyticum or U. parvum, using qRT-PCR, RNA sequencing, multi-analyte immunoassay, and flow cytometry. Ureaplasma exposure in native HBMEC reduced monocyte chemoattractant protein (MCP)-3 mRNA expression (p < 0.01, vs. broth). In co-stimulated HBMEC, Ureaplasma spp. attenuated LPS-evoked mRNA responses for C-X-C chemokine ligand 5, MCP-1, and MCP-3 (p < 0.05, vs. LPS) and mitigated LPS-driven interleukin (IL)-1α protein secretion, as well as IL-8 mRNA and protein responses (p < 0.05). Furthermore, Ureaplasma isolates increased C-X-C chemokine receptor 4 mRNA levels in native and LPS co-stimulated HBMEC (p < 0.05). The presented results may imply immunomodulatory capacities of Ureaplasma spp. which may ultimately promote chronic colonization and long-term neuroinflammation.
Ureaplasma species (spp.) are considered commensals of the adult genitourinary tract, but have been associated with chorioamnionitis, preterm birth, and invasive infections in neonates, including meningitis. Data on mechanisms involved in Ureaplasma-driven neuroinflammation are scarce. The present study addressed brain inflammatory responses in preterm lambs exposed to Ureaplasma parvum (UP) in utero. 7 days after intra-amniotic injection of UP (n = 10) or saline (n = 11), lambs were surgically delivered at gestational day 128–129. Expression of inflammatory markers was assessed in different brain regions using qRT-PCR and in cerebrospinal fluid (CSF) by multiplex immunoassay. CSF was analyzed for UP presence using ureB-based real-time PCR, and MRI scans documented cerebral white matter area and cortical folding. Cerebral tissue levels of atypical chemokine receptor (ACKR) 3, caspases 1-like, 2, 7, and C–X–C chemokine receptor (CXCR) 4 mRNA, as well as CSF interleukin-8 protein concentrations were significantly increased in UP-exposed lambs. UP presence in CSF was confirmed in one animal. Cortical folding and white matter area did not differ among groups. The present study confirms a role of caspases and the transmembrane receptors ACKR3 and CXCR4 in Ureaplasma-driven neuroinflammation. Enhanced caspase 1-like, 2, and 7 expression may reflect cell death. Increased ACKR3 and CXCR4 expression has been associated with inflammatory central nervous system (CNS) diseases and impaired blood–brain barrier function. According to these data and previous in vitro findings from our group, we speculate that Ureaplasma-induced caspase and receptor responses affect CNS barrier properties and thus facilitate neuroinflammation.
Urinary, Circulating, and Tissue Biomonitoring Studies Indicate Widespread Exposure to Bisphenol A
(2012)
Bisphenol A (BPA) is one of the highest-volume chemicals produced worldwide, and human exposure to BPA is thought to be ubiquitous. Thus, there are concerns that the amount of BPA to which humans are exposed may cause adverse health effects. We examined many possibilities for why biomonitoring and toxicokinetic studies could come to seemingly conflicting conclusions. More than 80 published human biomonitoring studies that measured BPA concentrations in human tissues, urine, blood, and other fluids, along with two toxicokinetic studies of human BPA metabolism were examined. Unconjugated BPA was routinely detected in blood (in the nanograms per milliliter range), and conjugated BPA was routinely detected in the vast majority of urine samples (also in the nanograms per milliliter range). In stark contrast, toxicokinetic studies proposed that humans are not internally exposed to BPA. Available data from biomonitoring studies clearly indicate that the general population is exposed to BPA and is at risk from internal exposure to unconjugated BPA. The two toxicokinetic studies that suggested human BPA exposure is negligible have significant deficiencies, are directly contradicted by hypothesis-driven studies, and are therefore not reliable for risk assessment purposes.
Context:
Adrenal tumors have a prevalence of around 2% in the general population. Adrenocortical carcinoma (ACC) is rare but accounts for 2–11% of incidentally discovered adrenal masses. Differentiating ACC from adrenocortical adenoma (ACA) represents a diagnostic challenge in patients with adrenal incidentalomas, with tumor size, imaging, and even histology all providing unsatisfactory predictive values.
Objective:
Here we developed a novel steroid metabolomic approach, mass spectrometry-based steroid profiling followed by machine learning analysis, and examined its diagnostic value for the detection of adrenal malignancy.
Design:
Quantification of 32 distinct adrenal derived steroids was carried out by gas chromatography/mass spectrometry in 24-h urine samples from 102 ACA patients (age range 19–84 yr) and 45 ACC patients (20–80 yr). Underlying diagnosis was ascertained by histology and metastasis in ACC and by clinical follow-up [median duration 52 (range 26–201) months] without evidence of metastasis in ACA. Steroid excretion data were subjected to generalized matrix learning vector quantization (GMLVQ) to identify the most discriminative steroids.
Results:
Steroid profiling revealed a pattern of predominantly immature, early-stage steroidogenesis in ACC. GMLVQ analysis identified a subset of nine steroids that performed best in differentiating ACA from ACC. Receiver-operating characteristics analysis of GMLVQ results demonstrated sensitivity = specificity = 90% (area under the curve = 0.97) employing all 32 steroids and sensitivity = specificity = 88% (area under the curve = 0.96) when using only the nine most differentiating markers.
Conclusions:
Urine steroid metabolomics is a novel, highly sensitive, and specific biomarker tool for discriminating benign from malignant adrenal tumors, with obvious promise for the diagnostic work-up of patients with adrenal incidentalomas.
Usability of a mHealth solution using speech recognition for point-of-care diagnostic management
(2023)
The administrative burden for physicians in the hospital can affect the quality of patient care. The Service Center Medical Informatics (SMI) of the University Hospital Würzburg developed and implemented the smartphone-based mobile application (MA) ukw.mobile1 that uses speech recognition for the point-of-care ordering of radiological examinations. The aim of this study was to examine the usability of the MA workflow for the point-of-care ordering of radiological examinations. All physicians at the Department of Trauma and Plastic Surgery at the University Hospital Würzburg, Germany, were asked to participate in a survey including the short version of the User Experience Questionnaire (UEQ-S) and the Unified Theory of Acceptance and Use of Technology (UTAUT). For the analysis of the different domains of user experience (overall attractiveness, pragmatic quality and hedonic quality), we used a two-sided dependent sample t-test. For the determinants of the acceptance model, we employed regression analysis. Twenty-one of 30 physicians (mean age 34 ± 8 years, 62% male) completed the questionnaire. Compared to the conventional desktop application (DA) workflow, the new MA workflow showed superior overall attractiveness (mean difference 2.15 ± 1.33), pragmatic quality (mean difference 1.90 ± 1.16), and hedonic quality (mean difference 2.41 ± 1.62; all p < .001). The user acceptance measured by the UTAUT (mean 4.49 ± 0.41; min. 1, max. 5) was also high. Performance expectancy (beta = 0.57, p = .02) and effort expectancy (beta = 0.36, p = .04) were identified as predictors of acceptance, the full predictive model explained 65.4% of its variance. Point-of-care mHealth solutions using innovative technology such as speech-recognition seem to address the users’ needs and to offer higher usability in comparison to conventional technology. Implementation of user-centered mHealth innovations might therefore help to facilitate physicians’ daily work.
S fimbrial adhesins (Sfa) enable pathogenic Escherichia coli strains to bind to sialic acid-containing eucaryotic receptor molecules. In order to determine the inftuence of culture conditions on the expression of the sfa determinant in a wild-type strain, we fused the gene lacZ, coding for the enzyme ß-galactosidase, to the sfaA gene, responsible for the major protein subunit of S fimbriae. By using a plasmid which carries an R6K origin, the sfaA-Iac hybrid construct was site-specifically integrated into the chromosome of the uropathogenic E. coli strain S36WT. The expression of lacZ, which was under the control of the sfa wild-type promoters, was now equivalent to the sfa expression of strain S36WT. With the help of this particular wild-type construct, it was demonstrated that the sfa determinant is better expressed on solid media than in liquid broth. The growth rate bad a strong inftuence on Sfa expression under aerobic but not under anaerobic conditions. Production of Sfa was further regulated by catabolite repression, osmolarity, and temperature.
As structural membrane components and signaling effector molecules sphingolipids influence a plethora of host cell functions, and by doing so also the replication of viruses. Investigating the effects of various inhibitors of sphingolipid metabolism in primary human peripheral blood lymphocytes (PBL) and the human B cell line BJAB we found that not only the sphingosine kinase (SphK) inhibitor SKI-II, but also the acid ceramidase inhibitor ceranib-2 efficiently inhibited measles virus (MV) replication. Virus uptake into the target cells was not grossly altered by the two inhibitors, while titers of newly synthesized MV were reduced by approximately 1 log (90%) in PBL and 70–80% in BJAB cells. Lipidomic analyses revealed that in PBL SKI-II led to increased ceramide levels, whereas in BJAB cells ceranib-2 increased ceramides. SKI-II treatment decreased sphingosine-1-phosphate (S1P) levels in PBL and BJAB cells. Furthermore, we found that MV infection of lymphocytes induced a transient (0.5–6 h) increase in S1P, which was prevented by SKI-II. Investigating the effect of the inhibitors on the metabolic (mTORC1) activity we found that ceranib-2 reduced the phosphorylation of p70 S6K in PBL, and that both inhibitors, ceranib-2 and SKI-II, reduced the phosphorylation of p70 S6K in BJAB cells. As mTORC1 activity is required for efficient MV replication, this effect of the inhibitors is one possible antiviral mechanism. In addition, reduced intracellular S1P levels affect a number of signaling pathways and functions including Hsp90 activity, which was reported to be required for MV replication. Accordingly, we found that pharmacological inhibition of Hsp90 with the inhibitor 17-AAG strongly impaired MV replication in primary PBL. Thus, our data suggest that treatment of lymphocytes with both, acid ceramidase and SphK inhibitors, impair MV replication by affecting a number of cellular activities including mTORC1 and Hsp90, which alter the metabolic state of the cells causing a hostile environment for the virus.
The urban micro climate has been increasingly recognised as an important aspect for urban planning. Therefore, urban planners need reliable information on the micro climatic characteristics of the urban environment. A suitable spatial scale and large spatial coverage are important requirements for such information. This thesis presents a conceptual framework for the use of airborne hyperspectral data to support urban micro climate characterisation, taking into account the information needs of urban planning. The potential of hyperspectral remote sensing in characterising the micro climate is demonstrated and evaluated by applying HyMap airborne hyperspectral and height data to a case study of the German city of Munich. The developed conceptual framework consists of three parts. The first is concerned with the capabilities of airborne hyperspectral remote sensing to map physical urban characteristics. The high spatial resolution of the sensor allows to separate the relatively small urban objects. The high spectral resolution enables the identification of the large range of surface materials that are used in an urban area at up to sub-pixel level. The surface materials are representative for the urban objects of which the urban landscape is composed. These spatial urban characteristics strongly influence the urban micro climate. The second part of the conceptual framework provides an approach to use the hyperspectral surface information for the characterisation of the urban micro climate. This can be achieved by integrating the remote sensing material map into a micro climate model. Also spatial indicators were found to provide useful information on the micro climate for urban planners. They are commonly used in urban planning to describe building blocks and are related to several micro climatic parameters such as temperature and humidity. The third part of the conceptual framework addresses the combination and presentation of the derived indicators and simulation results under consideration of the planning requirements. Building blocks and urban structural types were found to be an adequate means to group and present the derived information for micro climate related questions to urban planners. The conceptual framework was successfully applied to a case study in Munich. Airborne hyperspectral HyMap data has been used to derive a material map at sub-pixel level by multiple endmember linear spectral unmixing. This technique was developed by the German Research Centre for Geosciences (GFZ) for applications in Dresden and Potsdam. A priori information on building locations was used to support the separation between spectrally similar materials used both on building roofs and non-built surfaces. In addition, surface albedo and leaf area index are derived from the HyMap data. The sub-pixel material map supported by object height data is then used to derive spatial indicators, such as imperviousness or building density. To provide a more detailed micro climate characterisation at building block level, the surface materials, albedo, leaf area index (LAI) and object height are used as input for simulations with the micro climate model ENVI-met. Concluding, this thesis demonstrated the potential of hyperspectral remote sensing to support urban micro climate characterisation. A detailed mapping of surface materials at sub-pixel level could be performed. This provides valuable, detailed information on a large range of spatial characteristics relevant to the assessment of the urban micro climate. The developed conceptual framework has been proven to be applicable to the case study, providing a means to characterise the urban micro climate. The remote sensing products and subsequent micro climatic information are presented at a suitable spatial scale and in understandable maps and graphics. The use of well-known spatial indicators and the framework of urban structural types can simplify the communication with urban planners on the findings on the micro climate. Further research is needed primarily on the sensitivity of the micro climate model towards the remote sensing based input parameters and on the general relation between climate parameters and spatial indicators by comparison with other cities.
Schistosomiasis is a widespread water-based disease that puts close to 800 million people at risk of infection with more than 250 million infected, mainly in sub-Saharan Africa. Transmission is governed by the spatial distribution of specific freshwater snails that act as intermediate hosts and the frequency, duration and extent of human bodies exposed to infested water sources during human water contact. Remote sensing data have been utilized for spatially explicit risk profiling of schistosomiasis. Since schistosomiasis risk profiling based on remote sensing data inherits a conceptual drawback if school-based disease prevalence data are directly related to the remote sensing measurements extracted at the location of the school, because the disease transmission usually does not exactly occur at the school, we took the local environment around the schools into account by explicitly linking ecologically relevant environmental information of potential disease transmission sites to survey measurements of disease prevalence. Our models were validated at two sites with different landscapes in Côte d’Ivoire using high- and moderateresolution remote sensing data based on random forest and partial least squares regression. We found that the ecologically relevant modelling approach explained up to 70% of the variation in Schistosoma infection prevalence and performed better compared to a purely pixelbased modelling approach. Furthermore, our study showed that model performance increased as a function of enlarging the school catchment area, confirming the hypothesis that suitable environments for schistosomiasis transmission rarely occur at the location of survey measurements.
Background: The present anonymous multicenter online survey was conducted to evaluate the application of regional anaesthesia techniques as well as the used local anaesthetics and adjuncts at German and Austrian university hospitals. Methods: 39 university hospitals were requested to fill in an online questionnaire, to determine the kind of regional anaesthesia and preferred drugs in urology, obstetrics and gynaecology. Results: 33 hospitals responded. No regional anaesthesia is conducted in 47% of the minor gynaecological and 44% of the urological operations; plain bupivacaine 0.5% is used in 38% and 47% respectively. In transurethral resections of the prostate and bladder no regional anaesthesia is used in 3% of the responding hospitals, whereas plain bupivacaine 0.5% is used in more than 90%. Regional anaesthesia is only used in selected major gynaecological and urological operations. On the contrary to the smaller operations, the survey revealed a large variety of used drugs and mixtures. Almost 80% prefer plain bupivacaine or ropivacaine 0.5% in spinal anaesthesia in caesarean section. Similarly to the use of drugs in major urological and gynaecological operations a wide range of drugs and adjuncts is used in epidural anaesthesia in caesarean section and spontaneous delivery. Conclusions: Our results indicate a certain agreement in short operations in spinal anaesthesia. By contrast, a large variety concerning the anaesthesiological approach in larger operations as well as in epidural analgesia in obstetrics could be revealed, the causes of which are assumed to be primarily rooted in particular departmental structures.
In the Lyme disease spirochete Borrelia burgdorferi, the outer membrane protein P66 is capable of pore formation with an atypical high single-channel conductance of 11 nS in 1 M KCl, which suggested that it could have a larger diameter than ‘normal’ Gram-negative bacterial porins. We studied the diameter of the P66 channel by analyzing its single-channel conductance in black lipid bilayers in the presence of different nonelectrolytes with known hydrodynamic radii. We calculated the filling of the channel with these nonelectrolytes and the results suggested that nonelectrolytes (NEs) with hydrodynamic radii of 0.34 nm or smaller pass through the pore, whereas neutral molecules with greater radii only partially filled the channel or were not able to enter it at all. The diameter of the entrance of the P66 channel was determined to be \(\leq\)1.9 nm and the channel has a central constriction of about 0.8 nm. The size of the channel appeared to be symmetrical as judged from one-sidedness of addition of NEs. Furthermore, the P66-induced membrane conductance could be blocked by 80–90% by the addition of the nonelectrolytes PEG 400, PEG 600 and maltohexaose to the aqueous phase in the low millimolar range. The analysis of the power density spectra of ion current through P66 after blockage with these NEs revealed no chemical reaction responsible for channel block. Interestingly, the blockage of the single-channel conductance of P66 by these NEs occurred in about eight subconductance states, indicating that the P66 channel could be an oligomer of about eight individual channels. The organization of P66 as a possible octamer was confirmed by Blue Native PAGE and immunoblot analysis, which both demonstrated that P66 forms a complex with a mass of approximately 460 kDa. Two dimension SDS PAGE revealed that P66 is the only polypeptide in the complex.
Use of polyhexanide and nanomedicine approach for effective treatments of cutaneous leishmaniasis
(2015)
Despite huge suffering caused by cutaneous leishmaniasis (CL), there is no effective and affordable treatment strategy against CL and no licensed vaccines. The current treatments show limited efficacy and high toxicity. Improved therapies through discovery of novel drugs and/or an alternative treatment approaches are/is urgently needed. We aimed at identifying a novel antileishmanial agent and developing an innovative nanoparticle (NP) based platform for safe and effective treatments against CL. We discovered that polyhexanide (PHMB), a widely used antimicrobial polymer and wound antisepsis, shows an inherent antileishmanial activity at submicromolar concentrations. PHMB appears to kill L. major parasites via a dual mechanism involving disruption of membrane integrity and selective chromosome condensation. However, host chromosomes binding appear to be limited by exclusion from mammalian cell nuclei. Moreover, we attempted to establish effective drug delivery systems that overcome the various shortcomings in the present treatment of CL. In this scenario, we initially studied the cellular interactions of NPs and their uptake mechanisms into mammalian cells before applying them in drug delivery system. We obtained clear evidence for the involvement of multiple endocytic routes to internalize NPs. Physicochemical properties of NPs, cell type, temperature and pathogenesis of the target diseases were shown to be determinant factors. Thereafter, a mechanism based host- and pathogen-directed combination therapy comprising PHMB and CpG ODN immunomodulator was established for overall synergistic effect against CL. It simultaneously targets the pathogen and the host immunity with effective delivery system. The results show that PHMB binds to CpG ODN and form stable nanopolyplexes for efficient cell entry and therapy. The nanopolyplexes displayed enhanced cellular uptake and antileishmanial potency while drastically reducing the toxicity against mammalian cells. In conclusion, our findings clearly indicate that PHMB can be used as effective candidate drug against CL and as non-viral delivery of immunomodulatorynucleic acids. Moreover, our proof-of concept study showed nanomedicine approaches are effective strategy to challenge CL and other human diseases.
Tumor-induced angiogenesis is of major interest for oncology research. Vascular endothelial growth factor (VEGF) is the most potent angiogenic factor characterized so far. VEGF blockade was shown to be sufficient for angiogenesis inhibition and subsequent tumor regression in several preclinical tumor models. Bevacizumab was the first treatment targeting specifically tumor-induced angiogenesis through VEGF blockade to be approved by the Food and Drugs Administration (FDA) for cancer treatment. However, after very promising results in preclinical evaluations, VEGF blockade did not show the expected success in patients. Some tumors became resistant to VEGF blockade. Several factors have been accounted responsible, the over-expression of other angiogenic factors, the noxious influence of VEFG blockade on normal tissues, the selection of hypoxia resistant neoplastic cells, the recruitment of hematopoietic progenitor cells and finally the transient nature of angiogenesis inhibition by VEGF blockade. The development of blocking agents against other angiogenic factors like placental growth factor (PlGF) and Angiopoietin-2 (Ang-2) allows the development of an anti-angiogenesis strategy adapted to the profile of the tumor.
Oncolytic virotherapy uses the natural propensity of viruses to colonize tumors to treat cancer. The recombinant vaccinia virus GLV-1h68 was shown to infect, colonize and lyse several tumor types. Its descendant GLV-1h108, expressing an anti-VEGF antibody, was proved in previous studies to inhibit efficiently tumor induced angiogenesis. Additional VACVs expressing single chain antibodies (scAb) antibodies against PlGF and Ang-2 alone or in combination with anti VEGF scAb were designed.
In this study, VACV-mediated anti-angiogenesis treatments have been evaluated in several preclinical tumor models. The efficiency of PlGF blockade, alone or in combination with VEGF, mediated by VACV has been established and confirmed. PlGF inhibition alone or with VEGF reduced tumor burden 5- and 2-folds more efficiently than the control virus, respectively.
Ang-2 blockade efficiency for cancer treatment gave controversial results when tested in different laboratories. Here we demonstrated that unlike VEGF, the success of Ang-2 blockade is not only correlated to the strength of the blockade. A particular balance between Ang-2, VEGF and Ang-1 needs to be induced by the treatment to see a regression of the tumor and an improved survival. We saw that Ang-2 inhibition delayed tumor growth up to 3-folds compared to the control virus. These same viruses induced statistically significant tumor growth delays. This study unveiled the need to establish an angiogenic profile of the tumor to be treated as well as the necessity to better understand the synergic effects of VEGF and Ang-2. In addition angiogenesis inhibition by VACV-mediated PlGF and Ang-2 blockade was able to reduce the number of metastases and migrating tumor cells (even more efficiently than VEGF blockade).
VACV colonization of tumor cells, in vitro, was limited by VEGF, when the use of the anti-VEGF VACV GLV-1h108 drastically improved the colonization efficiency up to 2-fold, 72 hours post-infection. These in vitro data were confirmed by in vivo analysis of tumors. Fourteen days post-treatment, the anti-VEGF virus GLV-1h108 was colonizing 78.8% of the tumors when GLV-1h68 colonization rate was 49.6%. These data confirmed the synergistic effect of VEGF blockade and VACV replication for tumor regression.
Three of the tumor cell lines used to assess VACV-mediated angiogenesis inhibition were found, in certain conditions, to mimic either endothelial cell or pericyte functions, and participate directly to the vascular structure. The expression by these tumor cells of e-selectin, p-selectin, ICAM-1 and VCAM-1, normally expressed on activated endothelial cells, corroborates our findings. These proteins play an important role in immune cell recruitment, and there amount vary in presence of VEGF, PlGF and Ang-2, confirming the involvement of angiogenic factors in the immuno-modulatory abilities of tumors.
In this study VACV-mediated angiogenesis blockade proved its potential as a therapeutic agent able to treat different tumor types and prevent resistance observed during bevacizumab treatment by acting on different factors. First, the expression of several antibodies by VACV would prevent another angiogenic factor to take over VEGF and stimulate angiogenesis. Then, the ability of VACV to infect tumor cells would prevent them to form blood vessel-like structures to sustain tumor growth, and the localized delivery of the antibody would decrease the risk of adverse effects. Next, the blockade of angiogenic factors would improve VACV replication and decrease the immune-modulatory effect of tumors. Finally the fact that angiogenesis blockade lasts until total regression of the tumor would prevent the recovery of the tumor-associated vasculature and the relapse of patients.
Patients with genetic cardiomyopathy that involves myocardial hypertrophy often develop clinically relevant arrhythmias that increase the risk of sudden death. Consequently, guidelines for medical device therapy were established for hypertrophic cardiomyopathy, but not for conditions with only anecdotal evidence of arrhythmias, like Fabry cardiomyopathy. Patients with Fabry cardiomyopathy progressively develop myocardial fibrosis, and sudden cardiac death occurs regularly. Because 24-hour Holier electrocardiograms (ECGs) might not detect clinically important arrhythmias, we tested an implanted loop recorder for continuous heart rhythm surveillance and determined its impact on therapy. This prospective study included 16 patients (12 men) with advanced Fabry cardiomyopathy, relevant hypertrophy, and replacement fibrosis in "loco typico." No patients previously exhibited clinically relevant arrhythmias on Holier ECGs. Patients received an implantable loop recorder and were prospectively followed with telemedicine for a median of 1.2 years (range 0.3 to 2.0 years). The primary end point was a clinically meaningful event, which required a therapy change, captured with the loop recorder. Patients submitted data regularly (14 +/- 11 times per month). During follow-up, 21 events were detected (including 4 asystole, i.e., ECG pauses >= 3 seconds) and 7 bradycardia events; 5 episodes of intermittent atrial fibrillation (>3 minutes) and 5 episodes of ventricular tachycardia (3 sustained and 2 nonsustained). Subsequently, as defined in the primary end point, 15 events leaded to a change of therapy. These patients required therapy with a pacemaker or cardioverter defibrillator implantation and/or anticoagulation therapy for atrial fibrillation. In conclusion, clinically relevant arrhythmias that require further device and/or medical therapy are often missed with Holier ECGs in patients with advanced stage Fabry cardiomyopathy, but they can be detected by telemonitoring with an implantable loop recorder.
The relevance of user experience in safety–critical domains has been questioned and lacks empirical investigation. Based on previous studies examining user experience in consumer technology, we conducted an online survey on positive experiences with interactive technology in acute care. The participants of the study consisted of anaesthesiologists, nurses, and paramedics (N = 55) from three German cities. We report qualitative and quantitative data examining (1) the relevance and notion of user experience, (2) motivational orientations and psychological need satisfaction, and (3) potential correlates of hedonic, eudaimonic, and extrinsic motivations such as affect or meaning. Our findings reveal that eudaimonia was the most salient aspect in these experiences and that the relevance of psychological needs is differently ranked than in experiences with interactive consumer technology. We conclude that user experience should be considered in safety–critical domains, but research needs to develop further tools and methods to address the domain-specific requirements.
Transcriptome analysis of individual cells by single-cell RNA-seq (scRNA-seq) has become routine for eukaryotic tissues, even being applied to whole multicellular organisms. In contrast, developing methods to read the transcriptome of single bacterial cells has proven more challenging, despite a general perception of bacteria as much simpler than eukaryotes. Bacterial cells are harder to lyse, their RNA content is about two orders of magnitude lower than that of eukaryotic cells, and bacterial mRNAs are less stable than their eukaryotic counterparts. Most importantly, bacterial transcripts lack functional poly(A) tails, precluding simple adaptation of popular standard eukaryotic scRNA-seq protocols that come with the double advantage of specific mRNA amplification and concomitant depletion of rRNA. However, thanks to very recent breakthroughs in methodology, bacterial scRNA-seq is now feasible. This short review will discuss recently published bacterial scRNA-seq approaches (MATQ-seq, microSPLiT, and PETRI-seq) and a spatial transcriptomics approach based on multiplexed in situ hybridization (par-seqFISH). Together, these novel approaches will not only enable a new understanding of cell-to-cell variation in bacterial gene expression, they also promise a new microbiology by enabling high-resolution profiling of gene activity in complex microbial consortia such as the microbiome or pathogens as they invade, replicate, and persist in host tissue.
Positional plagiocephaly (PP) is the most common skull deformity in infants. Different classification systems exist for graduating the degree of PP, but all of these systems are based on two-dimensional (2D) parameters. This limitation leads to several problems stemming from the fact that 2D parameters are used to classify the three-dimensional (3D) shape of the head. We therefore evaluate existing measurement parameters and validate a newly developed 3D parameter for quantifying PP. Additionally, we present a new classification of PP based on a 3D parameter. 210 patients with PP and 50 patients without PP were included in this study. Existing parameters (2D and 3D) and newly developed volume parameters based on a 3D stereophotogrammetry scan were validated using ROC curves. Additionally, thresholds for the new 3D parameter of a 3D asymmetry index were assessed. The volume parameter 3D asymmetry index quantifies PP equally as well as the gold standard of 30° diagonal difference. Moreover, a 3D asymmetry index allows for a 3D-based classification of PP. The 3D asymmetry index can be used to define the degree of PP. It is easily applicable in stereophotogrammetric datasets and allows for comparability both intra- and inter-individually as well as for scientific analysis.
Background: Due to the importance of radiologic examinations, such as X-rays or computed tomography scans, for many clinical diagnoses, the optimal use of the radiology department is 1 of the primary goals of many hospitals.
Objective: This study aims to calculate the key metrics of this use by creating a radiology data warehouse solution, where data from radiology information systems (RISs) can be imported and then queried using a query language as well as a graphical user interface (GUI).
Methods: Using a simple configuration file, the developed system allowed for the processing of radiology data exported from any kind of RIS into a Microsoft Excel, comma-separated value (CSV), or JavaScript Object Notation (JSON) file. These data were then imported into a clinical data warehouse. Additional values based on the radiology data were calculated during this import process by implementing 1 of several provided interfaces. Afterward, the query language and GUI of the data warehouse were used to configure and calculate reports on these data. For the most common types of requested reports, a web interface was created to view their numbers as graphics.
Results: The tool was successfully tested with the data of 4 different German hospitals from 2018 to 2021, with a total of 1,436,111 examinations. The user feedback was good, since all their queries could be answered if the available data were sufficient. The initial processing of the radiology data for using them with the clinical data warehouse took (depending on the amount of data provided by each hospital) between 7 minutes and 1 hour 11 minutes. Calculating 3 reports of different complexities on the data of each hospital was possible in 1-3 seconds for reports with up to 200 individual calculations and in up to 1.5 minutes for reports with up to 8200 individual calculations.
Conclusions: A system was developed with the main advantage of being generic concerning the export of different RISs as well as concerning the configuration of queries for various reports. The queries could be configured easily using the GUI of the data warehouse, and their results could be exported into the standard formats Excel and CSV for further processing.
Using Expansion Microscopy to Visualize and Characterize the Morphology of Mitochondrial Cristae
(2020)
Mitochondria are double membrane bound organelles indispensable for biological processes such as apoptosis, cell signaling, and the production of many important metabolites, which includes ATP that is generated during the process known as oxidative phosphorylation (OXPHOS). The inner membrane contains folds called cristae, which increase the membrane surface and thus the amount of membrane-bound proteins necessary for the OXPHOS. These folds have been of great interest not only because of their importance for energy conversion, but also because changes in morphology have been linked to a broad range of diseases from cancer, diabetes, neurodegenerative diseases, to aging and infection. With a distance between opposing cristae membranes often below 100 nm, conventional fluorescence imaging cannot provide a resolution sufficient for resolving these structures. For this reason, various highly specialized super-resolution methods including dSTORM, PALM, STED, and SIM have been applied for cristae visualization. Expansion Microscopy (ExM) offers the possibility to perform super-resolution microscopy on conventional confocal microscopes by embedding the sample into a swellable hydrogel that is isotropically expanded by a factor of 4–4.5, improving the resolution to 60–70 nm on conventional confocal microscopes, which can be further increased to ∼ 30 nm laterally using SIM. Here, we demonstrate that the expression of the mitochondrial creatine kinase MtCK linked to marker protein GFP (MtCK-GFP), which localizes to the space between the outer and the inner mitochondrial membrane, can be used as a cristae marker. Applying ExM on mitochondria labeled with this construct enables visualization of morphological changes of cristae and localization studies of mitochondrial proteins relative to cristae without the need for specialized setups. For the first time we present the combination of specific mitochondrial intermembrane space labeling and ExM as a tool for studying internal structure of mitochondria.
The prediction of breeding values and phenotypes is of central importance for both livestock and crop breeding. In this study, we analyze the use of artificial neural networks (ANN) and, in particular, local convolutional neural networks (LCNN) for genomic prediction, as a region-specific filter corresponds much better with our prior genetic knowledge on the genetic architecture of traits than traditional convolutional neural networks. Model performances are evaluated on a simulated maize data panel (n = 10,000; p = 34,595) and real Arabidopsis data (n = 2,039; p = 180,000) for a variety of traits based on their predictive ability. The baseline LCNN, containing one local convolutional layer (kernel size: 10) and two fully connected layers with 64 nodes each, is outperforming commonly proposed ANNs (multi layer perceptrons and convolutional neural networks) for basically all considered traits. For traits with high heritability and large training population as present in the simulated data, LCNN are even outperforming state-of-the-art methods like genomic best linear unbiased prediction (GBLUP), Bayesian models and extended GBLUP, indicated by an increase in predictive ability of up to 24%. However, for small training populations, these state-of-the-art methods outperform all considered ANNs. Nevertheless, the LCNN still outperforms all other considered ANNs by around 10%. Minor improvements to the tested baseline network architecture of the LCNN were obtained by increasing the kernel size and of reducing the stride, whereas the number of subsequent fully connected layers and their node sizes had neglectable impact. Although gains in predictive ability were obtained for large scale data sets by using LCNNs, the practical use of ANNs comes with additional problems, such as the need of genotyping all considered individuals, the lack of estimation of heritability and reliability. Furthermore, breeding values are additive by design, whereas ANN-based estimates are not. However, ANNs also comes with new opportunities, as networks can easily be extended to account for additional inputs (omics, weather etc.) and outputs (multi-trait models), and computing time increases linearly with the number of individuals. With advances in high-throughput phenotyping and cheaper genotyping, ANNs can become a valid alternative for genomic prediction.
This paper discusses the categorization of Quranic chapters by major phases of Prophet Mohammad’s messengership using machine learning algorithms. First, the chapters were categorized by places of revelation using Support Vector Machine and naïve Bayesian classifiers separately, and their results were compared to each other, as well as to the existing traditional Islamic and western orientalists classifications. The chapters were categorized into Meccan (revealed in Mecca) and Medinan (revealed in Medina). After that, chapters of each category were clustered using a kind of fuzzy-single linkage clustering approach, in order to correspond to the major phases of Prophet Mohammad’s life. The major phases of the Prophet’s life were manually derived from the Quranic text, as well as from the secondary Islamic literature e.g hadiths, exegesis. Previous studies on computing the places of revelation of Quranic chapters relied heavily on features extracted from existing background knowledge of the chapters. For instance, it is known that Meccan chapters contain mostly verses about faith and related problems, while Medinan ones encompass verses dealing with social issues, battles…etc. These features are by themselves insufficient as a basis for assigning the chapters to their respective places of revelation. In fact, there are exceptions, since some chapters do contain both Meccan and Medinan features. In this study, features of each category were automatically created from very few chapters, whose places of revelation have been determined through identification of historical facts and events such as battles, migration to Medina…etc. Chapters having unanimously agreed places of revelation were used as the initial training set, while the remaining chapters formed the testing set. The classification process was made recursive by regularly augmenting the training set with correctly classified chapters, in order to classify the whole testing set. Each chapter was preprocessed by removing unimportant words, stemming, and representation with vector space model. The result of this study shows that, the two classifiers have produced useable results, with an outperformance of the support vector machine classifier. This study indicates that, the proposed methodology yields encouraging results for arranging Quranic chapters by phases of Prophet Mohammad’s messengership.
Almost all life forms on earth have adapted to the most impactful and most predictable recurring change in environmental condition, the cycle of day and night, caused by the axial rotation of the planet. As a result many animals have evolved intricate endogenous clocks, which adapt and synchronize the organisms’ physiology, metabolism and behaviour to the daily change in environmental conditions. The scientific field researching these endogenous clocks is called chronobiology and has steadily grown in size, scope and relevance since the works of the earliest pioneers in the 1960s.
The number one model organism for the research of circadian clocks is the fruit fly, Drosophila melanogaster, whose clock serves as the entry point to understanding the basic inner workings of such an intricately constructed endogenous timekeeping system. In this thesis it was attempted to combine the research on the circadian clock with the techniques of optogenetics, a fairly new scientific field, launched by the discovery of Channelrhodopsin 2 just over 15 years ago. Channelrhodopsin 2 is a light-gated ion channel found in the green alga Chlamydomonas reinhardtii. In optogenetics, researches use these light-gated ion channels like Channelrhodopsin 2 by heterologously expressing them in cells and tissues of other organisms, which can then be stimulated by the application of light. This is most useful when studying neurons, as these channels provide an almost non-invasive tool to depolarize the neuronal plasma membranes at will. The goal of this thesis was to develop an optogenetic tool, which would be able to influence and phase shift the circadian clock of Drosophila melanogaster upon illumination. A phase shift is the adaptive response of the circadian clock to an outside stimulus that signals a change in the environmental light cycle. An optogenetic tool, able to influence and phase shift the circadian clock predictably and reliably, would open up many new ways and methods of researching the neuronal network of the clock and which neurons communicate to what extent, ultimately synchronizing the network.
The first optogenetic tool to be tested in the circadian clock of Drosophila melanogaster was ChR2-XXL, a channelrhodopsin variant with dramatically increased expression levels and photocurrents combined with a prolonged open state. The specific expression of ChR2-XXL and of later constructs was facilitated by deploying the three different clock-specific GAL4-driver lines, clk856-gal4, pdf-gal4 and mai179-gal4. Although ChR2-XXL was shown to be highly effective at depolarizing neurons, these stimulations proved to be unable to significantly phase shift the circadian clock of Drosophila. The second series of experiments was conducted with the conceptually novel optogenetic tools Olf-bPAC and SthK-bPAC, which respectively combine a cyclic nucleotide-gated ion channel (Olf and SthK) with the light-activated adenylyl-cyclase bPAC. These tools proved to be quite useful when expressed in the motor neurons of instar-3 larvae of Drosophila, paralyzing the larvae upon illumination, as well as affecting body length. This way, these new tools could be precisely characterized, spawning a successfully published research paper, centered around their electrophysiological characterization and their applicability in model organisms like Drosophila. In the circadian clock however, these tools caused substantial damage, producing severe arrhythmicity and anomalies in neuronal development. Using a temperature-sensitive GAL80-line to delay the expression until after the flies had eclosed, yielded no positive results either. The last series of experiments saw the use of another new series of optogenetic tools, modelled after the Olf-bPAC, with bPAC swapped out for CyclOp, a membrane-bound guanylyl-cyclase, coupled with less potent versions of the Olf. This final attempt however also ended up being unsuccessful. While these tools could efficiently depolarize neuronal membranes upon illumination, they were ultimately unable to stimulate the circadian clock in way that would cause it to phase shift.
Taken together, these mostly negative results indicate that an optogenetic manipulation of the circadian clock of Drosophila melanogaster is an extremely challenging subject. As light already constitutes the most impactful environmental factor on the circadian clock, the combination of chronobiology with optogenetics demands the parameters of the conducted experiments to be tuned with an extremely high degree of precision, if one hopes to receive positive results from these types of experiments at all.
Using Photoionization to Investigate Reactive Boron Species and the Kinetics of Hydrocarbon Radicals
(2021)
This thesis highlights the importance of isomer-selective approaches for the complete analysis of chemical processes. The method of choice is photoelectron/photoion coincidence spectroscopy, which allows simultaneous detection of electrons and ions coming from a single ionization event. Ionization techniques are sensitive and can record multiple species simultaneously, rendering them ideal tools to probe molecular transformations. Coupling these setups to synchrotron radiation allows one to analyze complex mixtures with isomer selectivity, based on ionization energies and vibrational structure in the cation, without any prior separation steps. Only few setups exist that can be used to gather these data, although their impact and applicability is growing steadily in various fields. For closed-shell species an easier and more widely used method is gas-chromatography, but most open shell species would not survive the separation process. Due to the reactivity of radicals they have to be created by selectively converting stable precursor molecules. Depending on the radical generation method different properties can be investigated ranging from thermodynamic data, over concentrations in high temperature environments, to chemical kinetics.
The first part of this thesis deals with the determination of bimolecular rate constants. Isomeric hydrocarbon radicals were generated by a high intense UV light pulses and their kinetics with oxygen was measured. The pressure dependence of different isomers in the falloff region was compared to theoretical models, and their reactivity could be explained.
The second part deals with boron containing compounds in various electronic situations. The corresponding precursors were successfully synthesized or could be bought. They were subjected to fluorine atoms in chemical reactors or destroyed pyrolytically at high temperatures. Most investigated species exhibited vibronic effects that could be elucidated using high level computations.
Colorectal Cancer (CRC) is the third most common cancer in the US. The majority of CRC cases are due to deregulated WNT-signalling pathway. These alterations are mainly caused by mutations in the tumour suppressor gene APC or in CTNNB1, encoding the key effector protein of this pathway, β-Catenin. In canonical WNT-signalling, β-Catenin activates the transcription of several target genes, encoding for proteins involved in proliferation, such as MYC, JUN and NOTCH. Being such a critical regulator of these proto-oncogenes, the stability of β-Catenin is tightly regulated by the Ubiquitin-Proteasome System. Several E3 ligases that ubiquitylate and degrade β-Catenin have been described in the past, but the antagonists, the deubiquitylases, are still unknown. By performing an unbiased siRNA screen, the deubiquitylase USP10 was identified as a de novo positive regulator of β-Catenin stability in CRC derived cells. USP10 has previously been shown in the literature to regulate both mutant and wild type TP53 stability, to deubiquitylate NOTCH1 in endothelial cells and to be involved in the regulation of AMPKα signalling. Overall, however, its role in colorectal tumorigenesis remains controversial. By analysing publicly available protein and gene expression data from colorectal cancer patients, we have shown that USP10 is strongly upregulated or amplified upon transformation and that its expression correlates positively with CTNNB1 expression. In contrast, basal USP10 levels were found in non-transformed tissues, but surprisingly USP10 is upregulated in intestinal stem cells. Endogenous interaction studies in CRC-derived cell lines, with different extend of APCtruncation, revealed an APC-dependent mode of action for both proteins. Furthermore, by utilising CRISPR/Cas9, shRNA-mediated knock-down and overexpression of USP10, we could demonstrate a regulation of β-Catenin stability by USP10 in CRC cell lines. It is widely excepted that 2D cell culture systems do not reflect complexity, architecture and heterogeneity and are therefore not suitable to answer complex biological questions. To overcome this, we established the isolation, cultivation and genetically modification of murine intestinal organoids and utilised this system to study Usp10s role ex vivo. By performing RNA sequencing, dependent on different Usp10 levels, we were able to recapitulate the previous findings and demonstrated Usp10 as important regulator of β-dependent regulation of stem cell homeostasis. Since genetic depletion of USP10 resulted in down-regulation of β-Catenin-dependent transcription, therapeutic intervention of USP10 in colorectal cancer was also investigated. Commercial and newly developed inhibitors were tested for their efficacy against USP10, but failed to significantly inhibit USP10 activity in colorectal cancer cells. To validate the findings from this work also in vivo, development of a novel mouse model for colorectal cancer has begun. By combining CRISPR/Cas9 and classical genetic engineering with viral injection strategies, WT and genetically modified mice could be transformed and, at least in some animals, intestinal lesions were detectable at the microscopic level. The inhibition of USP10, which we could describe as a de novo tumour-specific regulator of β-Catenin, could become a new therapeutic strategy for colorectal cancer patients.
Oncogenic transformation of lung epithelial cells is a multistep process, frequently starting with the inactivation of tumour suppressors and subsequent development of activating mutations in proto-oncogenes, such as members of the PI3K or MAPK families. Cells undergoing transformation have to adjust to changes, including altered metabolic requirements. This is achieved, in part, by modulating the protein abundance of transcription factors. Here, we report that the ubiquitin carboxyl-terminal hydrolase 28 (USP28) enables oncogenic reprogramming by regulating the protein abundance of proto-oncogenes such as c-JUN, c-MYC, NOTCH and ∆NP63 at early stages of malignant transformation. USP28 levels are increased in cancer compared with in normal cells due to a feed-forward loop, driven by increased amounts of oncogenic transcription factors such as c-MYC and c-JUN. Irrespective of oncogenic driver, interference with USP28 abundance or activity suppresses growth and survival of transformed lung cells. Furthermore, inhibition of USP28 via a small-molecule inhibitor resets the proteome of transformed cells towards a ‘premalignant’ state, and its inhibition synergizes with clinically established compounds used to target EGFR\(^{L858R}\)-, BRAF\(^{V600E}\)- or PI3K\(^{H1047R}\)-driven tumour cells. Targeting USP28 protein abundance at an early stage via inhibition of its activity is therefore a feasible strategy for the treatment of early-stage lung tumours, and the observed synergism with current standard-of-care inhibitors holds the potential for improved targeting of established tumours.
∆Np63 is a master regulator of squamous cell identity and regulates several signaling pathways that crucially
contribute to the development of squamous cell carcinoma (SCC) tumors. Its contribution to coordinating the
expression of genes involved in oncogenesis, epithelial identity, DNA repair, and genome stability has been
extensively studied and characterized. For SCC, the expression of ∆Np63 is an essential requirement to
maintain the malignant phenotype. Additionally, ∆Np63 functionally contributes to the development of cancer
resistance toward therapies inducing DNA damage.
SCC patients are currently treated with the same conventional Cisplatin therapy as they would have been
treated 30 years ago. In contrast to patients with other tumor entities, the survival of SCC patients is limited,
and the efficacy of the current therapies is rather low. Considering the rising incidences of these tumor entities,
the development of novel SCC therapies is urgently required. Targeting ∆Np63, the transcription factor, is a
potential alternative to improve the therapeutic response and clinical outcomes of SCC patients.
However, ∆Np63 is considered “undruggable.” As is commonly observed in transcription factors, ∆Np63 does
not provide any suitable domains for the binding of small molecule inhibitors. ∆Np63 regulates a plethora of
different pathways and cellular processes, making it difficult to counteract its function by targeting
downstream effectors. As ∆Np63 is strongly regulated by the ubiquitin–proteasome system (UPS), the
development of deubiquitinating enzyme inhibitors has emerged as a promising therapeutic strategy to target
∆Np63 in SCC treatment.
This work involved identifying the first deubiquitinating enzyme that regulates ∆Np63 protein stability. Stateof-the-art SCC models were used to prove that USP28 deubiquitinates ∆Np63, regulates its protein stability,
and affects squamous transcriptional profiles in vivo and ex vivo. Accordingly, SCC depends on USP28 to
maintain essential levels of ∆Np63 protein abundance in tumor formation and maintenance. For the first time,
∆Np63, the transcription factor, was targeted in vivo using a small molecule inhibitor targeting the activity of
USP28. The pharmacological inhibition of USP28 was sufficient to hinder the growth of SCC tumors in
preclinical mouse models.
Finally, this work demonstrated that the combination of Cisplatin with USP28 inhibitors as a novel therapeutic
alternative could expand the limited available portfolio of SCC therapeutics. Collectively, the data presented
within this dissertation demonstrates that the inhibition of USP28 in SCC decreases ∆Np63 protein abundance,
thus downregulating the Fanconi anemia (FA) pathway and recombinational DNA repair. Accordingly, USP28
inhibition reduces the DNA damage response, thereby sensitizing SCC tumors to DNA damage therapies, such
as Cisplatin.
Squamous cell carcinomas are therapeutically challenging tumor entities. Low response rates to radiotherapy and chemotherapy are commonly observed in squamous patients and, accordingly, the mortality rate is relatively high compared to other tumor entities. Recently, targeting USP28 has been emerged as a potential alternative to improve the therapeutic response and clinical outcomes of squamous patients. USP28 is a catalytically active deubiquitinase that governs a plethora of biological processes, including cellular proliferation, DNA damage repair, apoptosis and oncogenesis. In squamous cell carcinoma, USP28 is strongly expressed and stabilizes the essential squamous transcription factor ΔNp63, together with important oncogenic factors, such as NOTCH1, c-MYC and c-JUN. It is presumed that USP28 is an oncoprotein; however, recent data suggest that the deubiquitinase also has an antineoplastic effect regulating important tumor suppressor proteins, such as p53 and CHK2. In this review, we discuss: (1) The emerging role of USP28 in cancer. (2) The complexity and mutational landscape of squamous tumors. (3) The genetic alterations and cellular pathways that determine the function of USP28 in squamous cancer. (4) The development and current state of novel USP28 inhibitors.
The mitotic spindle assembly checkpoint (SAC) maintains genome stability and marks an important target for antineoplastic therapies. However, it has remained unclear how cells execute cell fate decisions under conditions of SAC‐induced mitotic arrest. Here, we identify USP9X as the mitotic deubiquitinase of the X‐linked inhibitor of apoptosis protein (XIAP) and demonstrate that deubiquitylation and stabilization of XIAP by USP9X lead to increased resistance toward mitotic spindle poisons. We find that primary human aggressive B‐cell lymphoma samples exhibit high USP9X expression that correlate with XIAP overexpression. We show that high USP9X/XIAP expression is associated with shorter event‐free survival in patients treated with spindle poison‐containing chemotherapy. Accordingly, aggressive B‐cell lymphoma lines with USP9X and associated XIAP overexpression exhibit increased chemoresistance, reversed by specific inhibition of either USP9X or XIAP. Moreover, knockdown of USP9X or XIAP significantly delays lymphoma development and increases sensitivity to spindle poisons in a murine Eμ‐Myc lymphoma model. Together, we specify the USP9X–XIAP axis as a regulator of the mitotic cell fate decision and propose that USP9X and XIAP are potential prognostic biomarkers and therapeutic targets in aggressive B‐cell lymphoma.
Purpose
The value of bladder cancer (BC) substaging into macroscopic (pT3b) and microscopic (pT3a) perivesical fat extension in lymph node (Ln)-negative patients is controversially discussed and limited evidence for prognostic relevance of additional histopathological factors in pT3 BC exists. We evaluated the prognostic value of pT3 substaging and established pathological and clinical parameters with focus on tumor invasive front (TIF) and tumor size.
Methods
Specimens of 52 patients treated with radical cystectomy (RC) for pT3 a/b muscle-invasive BC were reviewed and re-evaluated by a pathologist specialized in uropathology. Clinical variables and standard histopathologic characteristics were assessed including TIF and tumor size. Their value as prognosticators for overall survival (OS) and recurrence-free survival (RFS) was evaluated.
Results
Mean age of patients was 67.55 years. Tumors were staged pT3a in 28 patients (53.8%) and pT3b in 24 (46.8%). Median OS was 34.51 months. Median tumor size was 3.2 cm, median TIF was 11.0 mm. Differences in OS between pT3a and pT3b were not significant (p = 0.45). Carcinoma in situ (CIS) and lymphovascular invasion (LVI) were significantly associated with pT3b tumors. Univariate analysis could not identify pathological prognosticators like TIF or tumor size for OS and RFS (p for all > 0.05).
Conclusion
No significant differences in OS or RFS were observed comparing Ln-negative pT3 BC following radical cystectomy. Additional pathologic variables like TIF could not be identified as prognosticator. Relevance of pT3 BC substaging needs reevaluation in larger prospective cohorts.
Multiple myeloma (MM) represents a haematological cancer characterized by the pathological hyper proliferation of antibody-producing B-lymphocytes. Patients typically suffer from kidney malfunction and skeletal disorders. In the context of MM, the transforming growth factor β (TGFβ) member Activin A was recently identified as a promoter of both accompanying symptoms. Because studies have shown that bone morphogenetic protein (BMP)-2-mediated activities are counteracted by Activin A, we analysed whether BMP2, which also binds to the Activin A receptors ActRII and ActRIIB but activates the alternative SMAD-1/5/8 pathway, can be used to antagonize Activin A activities, such as in the context of MM. Therefore three BMP2 derivatives were generated with modified binding activities for the type II (ActRIIB) and/or type I receptor (BMPRIA) showing either increased or decreased BMP2 activity. In the context of MM these BMP2 muteins show two functionalities since they act as a) an anti-proliferative/apoptotic agent against neoplastic B-cells, b) as a bone-formation promoting growth factor. The molecular basis of both activities was shown in two different cellular models to clearly rely on the properties of the investigated BMP2 muteins to compete for the binding of Activin A to the Activin type II receptors. The experimental outcome suggests new therapeutic strategies using BMP2 variants in the treatment of MM-related pathologies.
The electric propulsion system NanoFEEP was integrated and tested in orbit on the UWE-4 satellite, which marks the first successful demonstration of an electric propulsion system on board a 1U CubeSat. In-orbit characterization measurements of the heating process of the propellant and the power consumption of the propulsion system at different thrust levels are presented. Furthermore, an analysis of the thrust vector direction based on its effect on the attitude of the spacecraft is described. The employed heater liquefies the propellant for a duration of 30 min per orbit and consumes 103 ± 4 mW. During this time, the respective thruster can be activated. The propulsion system including one thruster head, its corresponding heater, the neutralizer and the digital components of the power processing unit consume 8.5 ± 0.1 mW ⋅μ A\(^{−1}\) + 184 ± 8.5 mW and scales with the emitter current. The estimated thrust directions of two thruster heads are at angles of 15.7 ± 7.6∘ and 13.2 ± 5.5∘ relative to their mounting direction in the CubeSat structure. In light of the very limited power on a 1U CubeSat, the NanoFEEP propulsion system renders a very viable option. The heater of subsequent NanoFEEP thrusters was already improved, such that the system can be activated during the whole orbit period.
Patients with rheumatoid arthritis (RA) are at higher risk to suffer from morbidity due to vaccine-preventable diseases and, thus, display an important target population to receive vaccines for protection from infectious complications. There have been only a few studies focusing on the administration of vaccines in RA patients with immunotherapy. Overall, antibody response rates against influenza or pneumococcal disease appeared to be only slightly lower than expected in healthy individuals. Crucial problems in the interpretation of data from studies in RA patients vaccinated against influenza and pneumococcal disease are the impaired comparability of studies due to different study designs and type of vaccines used, different health states among RA patients, heterogeneity in treatments including concomitant therapy with conventional DMARDs and glucocorticoids in addition to biological agents. Assessment of vaccination status should be performed in the initial work-up of patients with RA and should ideally be administered before initiation of immunotherapies or during stable disease. Due to differences in antibody responses and uncertainty regarding maintenance of protective antibodies, routine controls for antibody titers and specific strategies for earlier re-vaccination might be scheduled for patients with RA.