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Bats are natural reservoirs of numerous coronaviruses, including the potential ancestor of SARS-CoV-2. Knowledge concerning the interaction between coronaviruses and bat cells is sparse. We investigated the susceptibility of primary cells from Rhinolophus ferrumequinum and Myotis species, as well as of established and novel cell lines from Myotis myotis, Eptesicus serotinus, Tadarida brasiliensis and Nyctalus noctula, to SARS-CoV-2 infection. None of these cells were sensitive to infection, not even the ones expressing detectable levels of angiotensin-converting enzyme 2 (ACE2), which serves as the viral receptor in many mammalian species. The resistance to infection was overcome by expression of human ACE2 (hACE2) in three cell lines, suggesting that restriction to viral replication was due to a low expression of bat ACE2 (bACE2) or absence of bACE2 binding in these cells. Infectious virions were produced but not released from hACE2-transduced M. myotis brain cells. E. serotinus brain cells and M. myotis nasal epithelial cells expressing hACE2 efficiently controlled viral replication. This ability to control viral replication correlated with a potent interferon response. Our data highlight the existence of species-specific molecular barriers to viral replication in bat cells. These novel chiropteran cellular models are valuable tools to investigate the evolutionary relationships between bats and coronaviruses.Author summaryBats host ancestors of several viruses that cause serious disease in humans, as illustrated by the on-going SARS-CoV-2 pandemic. Progress in investigating bat-virus interactions have been hampered by a limited number of bat cell lines. We have generated primary cells and cell lines from several bat species that are relevant for coronavirus research. The varying susceptibilities of the cells to SARS-CoV-2 infection offered the opportunity to uncover some species-specific molecular restrictions to viral replication. All bat cells exhibited a potent entry-dependent restriction. Once this block was overcome by over-expression of human ACE2, which serves at the viral receptor, two bat cell lines controlled well viral replication, which correlated with the inability of the virus to counteract antiviral responses. Other cells potently inhibited viral release. Our novel bat cellular models contribute to a better understanding of the molecular interplays between bats and viruses.

The protozoan parasite Trypanosoma brucei is the causative agent of human African trypanosomiasis (HAT). The disease is fatal if it remains untreated, whereas most drug treatments are inadequate due to high toxicity, difficulties in administration, and low central nervous system penetration. T. brucei glycogen synthase kinase 3 short (TbGSK3s) is essential for parasite survival and thus represents a potential drug target that could be exploited for HAT treatment. Indirubins, effective leishmanicidals, provide a versatile scaffold for the development of potent GSK3 inhibitors. Herein, we report on the screening of 69 indirubin analogues against T. brucei bloodstream forms. Of these, 32 compounds had potent antitrypanosomal activity (half-maximal effective concentration 0.050 to 3.2 M) and good selectivity for the analogues over human HepG2 cells (range, 7.4- to over 641-fold). The majority of analogues were potent inhibitors of TbGSK3s, and correlation studies for an indirubin subset, namely, the 6-bromosubstituted 3=-oxime bearing an extra bulky substituent on the 3= oxime [(6-BIO-3=-bulky)-substituted indirubins], revealed a positive correlation between kinase inhibition and antitrypanosomal activity. Insights into this indirubin-TbGSK3s interaction were provided by structure-activity relationship studies. Comparison between 6-BIO-3=-bulky-substituted indirubin-treated parasites and parasites silenced for TbGSK3s by RNA interference suggested that the above-described compounds may target TbGSK3s in vivo. To further understand the molecular basis of the growth arrest brought about by the inhibition or ablation of TbGSK3s, we investigated the intracellular localization of TbGSK3s. TbGSK3s was present in cytoskeletal structures, including the flagellum and basal body area. Overall, these results give insights into the mode of action of 6-BIO-3=-bulky-substituted indirubins that are promising hits for antitrypanosomal drug discovery. Copyright © 2019 American Society for Microbiology. All Rights Reserved.

This paper presents a study to the moment-rotation aspects of two 3-member DVW reinforced timber connections with an inter-connecting steel plate used as middle member. Previous studies showed that reinforcing dowel-type timber connections with ‘densified veneer wood’ (DVW) and using expanded tube fasteners results in connections with superior structural properties compared to all conventional connections. In this connection type, the DVW prevents premature timber splitting. The tube fasteners aid a high initial stiffness, a high ductility and a high reliability. A drawback of the connection, already in a 3-member connection, is the total thickness. By using only two side members and a much thinner, steel middle member, the thickness is strongly reduced. The steel middle member is used as a connecting interface in a flitch plate connection. This generally results in a 50% reduction of the rotational stiffness. However, it is shown by an analytical and numerical study, that the rotational stiffness of two closely spaced, flitch plate DVW connections acting in series remains unchanged if certain conditions are fulfilled. Two full connection tests are performed to confirm the analytical and numerical results. Additionally, the paper presents a comparison to a conventional connection, which confirms the structural quality of the reinforced connection.

Introduction: I am addressing the question how decision-making of people with (mental) health issues can be successful. I argue that assisted decision-making in mental health is often the best way to secure that the interests of the patient are best valued. Method: For this purpose I conducted semi-structured[for full text, please go to the a.m. URL], 4th Research in Medical Education (RIME) Symposium 2015

Ductile behavior of timber connections with metal fasteners is essential to achieve a robust structure. Moreover, a ductile behavior of the fastener and the timber prior to failure is necessary to fulfill the boundary conditions for applying the Johansen theory (1949). If these boundary conditions are not fulfilled, the capacity of a connection is overestimated and brittle failure may occur. However, using sufficient spacing, end and edge distances reduces tensile stresses perpendicular to the grain, the main stresses initiating brittle failure. If in addition to that the influence of the relation between fastener diameter and timber volume is considered, brittle failure mechanisms can be avoided. This paper discusses quasi static tests carried out on dowelled connections with different spacing and loaded end distances chosen in accordance to the above criterion. The results were compared with the capacity calculation for dowelled connections of Eurocode 5, chapter 8.2, the design approach against block shear failure of Eurocode 5, Annex A, and the design proposal for the avoidance of block shear failure proposed by Hanhijärvi and Kevarinmäki (2008). The experimental failure load achieved was in all cases higher than predicted values by all three design approaches.

The solitary tract nucleus (NTS) conveys visceral information to diverse central networks involved in homeostatic regulation. Although afferent information content arriving at various CNS sites varies substantially, little is known about the contribution of processing within the NTS to these differences. Using retrograde dyes to identify specific NTS projection neurons, we recently reported that solitary tract (ST) afferents directly contact NTS neurons projecting to caudal ventrolateral medulla (CVLM) but largely only indirectly contact neurons projecting to the hypothalamic paraventricular nucleus (PVN). Since intrinsic properties impact information transmission, here we evaluated potassium channel expression and somatodendritic morphology of projection neurons and their relation to afferent information output directed to PVN or CVLM pathways. In slices, tracer-identified projection neurons were classified as directly or indirectly (polysynaptically) coupled to ST afferents by EPSC latency characteristics (directly coupled, jitter < 200 μs). In each neuron, voltage-dependent potassium currents (IK) were evaluated and, in representative neurons, biocytin-filled structures were quantified. Both CVLM- and PVN-projecting neurons had similar, tetraethylammonium-sensitive IK. However, only PVN-projecting NTS neurons displayed large transient, 4aminopyridine-sensitive, A-type currents (IKA). PVN-projecting neurons had larger cell bodies with more elaborate dendritic morphology than CVLM-projecting neurons. ST shocks faithfully (> 75%) triggered action potentials in CVLM-projecting neurons but spike output was uniformly low (< 20%) in PVN-projecting neurons. Pre-conditioning hyperpolarization removed IKA inactivation and attenuated ST-evoked spike generation along PVN but not CVLM pathways. Thus, multiple differences in structure, organization, synaptic transmission and ion channel expression tune the overall fidelity of afferent signals that reach these destinations.

The design of unreinforced holes in members made of glued laminated timber (GLT) is handled very differently in German and European standards and draft standards. The methodology based deficits of the design according to DIN 10522004 and especially the lack of design equations in Eurocode 5 initiated a research project comprising extensive tests with GLT building components and the development of a new design model, The influences of the parameters - beam depth, relative hole size, section force ratio and beam curvature - were investigated with a sample size of 68 bending members in structural dimensions. Essential experimental results consist in the description and classification of the stepped damage evolution and in the quantification of the load capacity effect of the mentioned parameters. A significant size effect has been confirmed. Tension stress perpendicular to grain direction was identified as the primary crack initiating action. The location of the crack on-set at the periphery of the hole is essentially determined by the cylindrical anisotropy of the material. An easily applicable design procedure based on Weibull theory was derived, accounting for the essential influences on load capacity, including the size effect and the inhomogeneous stress distribution at the periphery of the hole. The new experimental well substantiated design model works especially for holes in members with larger cross-sectional depths (1-2 m) more accurate design verifications as DIN 1052:2004 forwarding too high load capacities for large sized members with holes