Canonical transient receptor potential channel 5 (TRPC5) is a nonselective, Ca(2+)-permeable cation channel that belongs to the large family of transient receptor potential channels. It is ...predominantly found in the central nervous system with a high expression density in the hippocampus, the amygdala, and the frontal cortex. Several studies confirm that TRPC5 channels are implicated in the regulation of neurite length and growth cone morphology. We identified clemizole as a novel inhibitor of TRPC5 channels. Clemizole efficiently blocks TRPC5 currents and Ca(2+) entry in the low micromolar range (IC50 = 1.0-1.3 µM), as determined by fluorometric intracellular free Ca(2+) concentration (Ca(2+)i) measurements and patch-clamp recordings. Clemizole blocks TRPC5 currents irrespectively of the mode of activation, for example, stimulation of G protein-coupled receptors, hypo-osmotic buffer conditions, or by the direct activator riluzole. Electrophysiological whole-cell recordings revealed that the block was mostly reversible. Moreover, clemizole was still effective in blocking TRPC5 single channels in excised inside-out membrane patches, hinting to a direct block of TRPC5 by clemizole. Based on fluorometric Ca(2+)i measurements, clemizole exhibits a sixfold selectivity for TRPC5 over TRPC4β (IC50 = 6.4 µM), the closest structural relative of TRPC5, and an almost 10-fold selectivity over TRPC3 (IC50 = 9.1 µM) and TRPC6 (IC50 = 11.3 µM). TRPM3 and M8 as well as TRPV1, V2, V3, and V4 channels were only weakly affected by markedly higher clemizole concentrations. Clemizole was not only effective in blocking heterologously expressed TRPC5 homomers but also TRPC1:TRPC5 heteromers as well as native TRPC5-like currents in the U-87 glioblastoma cell line.
Self-esteem has been shown to be both predictive of and predicted by characteristics of romantic relationships. While there is an increasing number of studies yielding support for reciprocal ...influences between self-esteem and perceived conflict in romantic relationships, longitudinal transactions between these constructs from both partners' perspectives have not been studied systematically to date. Our aim was to close this gap. To that end, we examined the transactional and longitudinal interplay between self-esteem and perceived relationship conflict in continuing romantic couples from a dyadic perspective. Our sample consisted of N = 1,093 young adult female-male relationships from the German Family Panel. Individuals' self-esteem, perceived conflict frequency, and their perceptions of their partners' dysfunctional conflict styles (i.e., unconstructive behavior, withdrawal) were examined annually throughout a time span of five years. Based on dyadic bivariate latent change models, we tested our assumption that self-esteem and aspects of perceived relationship conflict are negatively interrelated within individuals and between partners both within and across time. We found one actor effect of self-esteem on changes in unconstructive behavior above and beyond initial unconstructive behavior levels, supporting self-broadcasting perspectives. Moreover, we found strong support for sociometer perspectives. Actor effects highlighted the importance of perceived conflict frequency for subsequent self-esteem changes. In addition, perceived conflict styles affected both partners' self-esteem. The results imply that perceiving conflict is a between-person process, and might be more important for the development of self-esteem than vice versa.
Background and Purpose
The transient receptor potential channel C5 (TRPC5) is a Ca2+‐permeable cation channel, which is predominantly expressed in the brain. TRPC5 is activated in a PLC‐dependent ...manner by, as yet, unidentified endogenous messengers. Recently, modulators of TRPC5, like Ca2+, pH and phospholipids, have been identified. However, the role of TRPC5 in vivo is only poorly understood. Novel specific modulators of TRPC5 might help to elucidate its function.
Experimental Approach
Novel modulators of TRPC5 were identified in a compound screening of approved drugs and natural compounds. The potency and selectivity of TRPC5‐activating compounds were determined by fluorometric calcium imaging. The biophysical properties of channel activation by these compounds were analysed using electrophysiological measurements.
Key Results
Riluzole was identified as a novel activator of TRPC5 (EC50 9.2 ± 0.5 μM) and its mechanism of action was shown to be independent of G protein signalling and PLC activity. Riluzole‐induced TRPC5 currents were potentiated by La3+ and, utilizing TRPC5 mutants that lack La3+ binding sites, it was confirmed that riluzole and La3+ activate TRPC5 by different mechanisms. Recordings of excised inside‐out patches revealed a relatively direct effect of riluzole on TRPC5.
Conclusions and Implications
Riluzole can activate TRPC5 heterologously expressed in HEK293 cells as well as those endogenously expressed in the U‐87 glioblastoma cell line. Riluzole does not activate any other member of the TRPC family and could, therefore, despite its action on other ion channels, be a useful pharmacological tool for identifying TRPC5‐specific currents in immortalized cell lines or in acutely isolated primary cells.
Salt‐affected farmlands are increasingly burdened by chlorides, carbonates, and sulfates of sodium, calcium, and magnesium. Intriguingly, the underlying physiological processes are studied almost ...always under NaCl stress. Two faba bean cultivars were subjected to low‐ and high‐salt treatments of NaCl, Na2SO4, and KCl. Assimilation rate and leaf water vapor conductance were reduced to approximately 25–30% without biomass reduction after 7 days salt stress, but this did not cause severe carbon shortage. The equimolar treatments of Na+, K+, and Cl− showed comparable accumulation patterns in leaves and roots, except for SO42− which did not accumulate. To gain a detailed understanding of the effects caused by the tested ion combinations, we performed nontargeted gas chromatography–mass spectrometry‐based metabolite profiling. Metabolic responses to various salts were in part highly linearly correlated, but only a few metabolite responses were common to all salts and in both cultivars. At high salt concentrations, only myo‐inositol, allantoin, and glycerophosphoglycerol were highly significantly increased in roots under all tested conditions. We discovered several metabolic responses that were preferentially associated with the presence of Na+, K+, or Cl−. For example, increases of leaf proline and decreases of leaf fumaric acid and malic acid were apparently associated with Cl− accumulation.
Salt stress is an abiotic factor limiting plant growth. Physiological mechanisms and metabolite impacts of the various cations and anions involved are addressed in this study. Assimilation rate and leaf water vapor conductance were reduced to approximately 25–30% without biomass reduction after 7 days salt stress, but this did not cause severe carbon shortage. The equimolar treatments of Na+, K+, and Cl− showed comparable accumulation patterns in leaves and roots, except for SO42− which did not accumulate. We discovered several metabolic responses that were preferentially associated with the presence of Na+, K+, or Cl−. For example, increases of leaf proline and decreases of leaf fumaric acid and malic acid were apparently associated with Cl− accumulation.
CuCrZr parts were fabricated by laser beam powder bed fusion (LB‐PBF) technique and subjected to different heat treatments. As a result, four different conditions were considered for further ...investigations, that is, the as‐built condition, conditions of maximum hardness (MH) and maximum electrical conductivity (MC), and a condition representing a compromise between hardness and conductivity (H&C). Microstructural evolution and performance under monotonic and cyclic loading were studied. Fracture surfaces revealed significant volume fractions of process‐induced defects such as lack‐of‐fusion (LoF) and pores, irrespective of the condition considered. The effect of these defects on the tensile behavior was found to be marginal, whereas the fatigue performance was noticeably affected due to multiple crack nucleation promoted by large LoF defects. Assessment by computed tomography (CT) revealed a strong influence of the geometry and therefore, of the scan path length, on resulting microstructure and defect population eventually rationalizing obvious discrepancies to the initial process parameter and material density optimization study.
Denisova Cave in southern Siberia is the type locality of the Denisovans, an archaic hominin group who were related to Neanderthals.sup.1-4. The dozen hominin remains recovered from the deposits also ...include Neanderthals.sup.5,6 and the child of a Neanderthal and a Denisovan.sup.7, which suggests that Denisova Cave was a contact zone between these archaic hominins. However, uncertainties persist about the order in which these groups appeared at the site, the timing and environmental context of hominin occupation, and the association of particular hominin groups with archaeological assemblages.sup.5,8-11. Here we report the analysis of DNA from 728 sediment samples that were collected in a grid-like manner from layers dating to the Pleistocene epoch. We retrieved ancient faunal and hominin mitochondrial (mt)DNA from 685 and 175 samples, respectively. The earliest evidence for hominin mtDNA is of Denisovans, and is associated with early Middle Palaeolithic stone tools that were deposited approximately 250,000 to 170,000 years ago; Neanderthal mtDNA first appears towards the end of this period. We detect a turnover in the mtDNA of Denisovans that coincides with changes in the composition of faunal mtDNA, and evidence that Denisovans and Neanderthals occupied the site repeatedly--possibly until, or after, the onset of the Initial Upper Palaeolithic at least 45,000 years ago, when modern human mtDNA is first recorded in the sediments.
Due to the growing interest in climbing, increasing importance has been given to research in the field of non-invasive, camera-based motion analysis. While existing work uses invasive technologies ...such as wearables or modified walls and holds, or focuses on competitive sports, we for the first time present a system that uses video analysis to automatically recognize six movement errors that are typical for novices with limited climbing experience. Climbing a complete route consists of three repetitive climbing phases. Therefore, a characteristic joint arrangement may be detected as an error in a specific climbing phase, while this exact arrangement may not considered to be an error in another climbing phase. That is why we introduced a finite state machine to determine the current phase and to check for errors that commonly occur in the current phase. The transition between the phases depends on which joints are being used. To capture joint movements, we use a fourth-generation iPad Pro with LiDAR to record climbing sequences in which we convert the climber’s 2-D skeleton provided by the Vision framework from Apple into 3-D joints using the LiDAR depth information. Thereupon, we introduced a method that derives whether a joint moves or not, determining the current phase. Finally, the 3-D joints are analyzed with respect to defined characteristic joint arrangements to identify possible motion errors. To present the feedback to the climber, we imitate a virtual mentor by realizing an application on the iPad that creates an analysis immediately after the climber has finished the route by pointing out the detected errors and by giving suggestions for improvement. Quantitative tests with three experienced climbers that were able to climb reference routes without any errors and intentionally with errors resulted in precision–recall curves evaluating the error detection performance. The results demonstrate that while the number of false positives is still in an acceptable range, the number of detected errors is sufficient to provide climbing novices with adequate suggestions for improvement. Moreover, our study reveals limitations that mainly originate from incorrect joint localizations caused by the LiDAR sensor range. With human pose estimation becoming increasingly reliable and with the advance of sensor capabilities, these limitations will have a decreasing impact on our system performance.
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•Fully α′ and β phase lattices were manufactured by L-PBF in TiTa.•Columnar grains were observed in the Ti25Ta lattice, but not in the Ti65Ta lattice.•α′ Ti25Ta is mechanically equal ...to β Ti65Ta for implant applications.•TiTa lattices showed superior fatigue behaviour to identical Ti-6Al-4V lattices.
Recent orthopaedic implant alloy design has focused on β-type Ti alloys, as the body centred cubic (BCC) crystal structure has the tendency to be characterised by a low elastic modulus. Nevertheless, the currently most used metal is Ti-6Al-4V, which mainly retains a hexagonal closed packed (HCP) crystal structure when produced by additive manufacturing. The benefits and disadvantages of the mechanical response of each crystal structure for implant applications is yet to be explored. Utilising the TiTa alloy system, low modulus Ti25Ta and Ti65Ta lattices were additively manufactured with opposing crystal structures of α′ martensite (HCP) and β grains (BCC). The lattices showed similar tensile, compressive and high cycle fatigue behaviour, indicating that the α' alloy was mechanically equal to the β alloy for implant applications. The mechanical properties of both the TiTa lattices were also superior to identically manufactured lattices in Ti-6Al-4V in both as-built and heat treated conditions.
Cell death is intrinsically linked with immunity. Disruption of an immune-activated MAPK cascade, consisting of MEKK1, MKK1/2, and MPK4, triggers cell death and autoimmunity through the ...nucleotide-binding leucine-rich repeat (NLR) protein SUMM2 and the MAPK kinase kinase MEKK2. In this study, we identify a Catharanthus roseus receptor-like kinase 1-like (CrRLK1L), named LETUM2/MEDOS1 (LET2/MDS1), and the glycosylphosphatidylinositol (GPI)-anchored protein LLG1 as regulators of mekk1-mkk1/2-mpk4 cell death. LET2/MDS1 functions additively with LET1, another CrRLK1L, and acts genetically downstream of MEKK2 in regulating SUMM2 activation. LET2/MDS1 complexes with LET1 and promotes LET1 phosphorylation, revealing an intertwined regulation between different CrRLK1Ls. LLG1 interacts with the ectodomain of LET1/2 and mediates LET1/2 transport to the plasma membrane, corroborating its function as a co-receptor of LET1/2 in the mekk1-mkk1/2-mpk4 cell death pathway. Thus, our data suggest that a trimeric complex consisting of two CrRLK1Ls LET1, LET2/MDS1, and a GPI-anchored protein LLG1 that regulates the activation of NLR SUMM2 for initiating cell death and autoimmunity.
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