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  1. Article ; Online: Principles of RNA recruitment to viral ribonucleoprotein condensates in a segmented dsRNA virus

    Sebastian Strauss / Julia Acker / Guido Papa / Daniel Desirò / Florian Schueder / Alexander Borodavka / Ralf Jungmann

    eLife, Vol

    2023  Volume 12

    Abstract: Rotaviruses transcribe 11 distinct RNAs that must be co-packaged prior to their replication to make an infectious virion. During infection, nontranslating rotavirus transcripts accumulate in cytoplasmic protein-RNA granules known as viroplasms that ... ...

    Abstract Rotaviruses transcribe 11 distinct RNAs that must be co-packaged prior to their replication to make an infectious virion. During infection, nontranslating rotavirus transcripts accumulate in cytoplasmic protein-RNA granules known as viroplasms that support segmented genome assembly and replication via a poorly understood mechanism. Here, we analysed the RV transcriptome by combining DNA-barcoded smFISH of rotavirus-infected cells. Rotavirus RNA stoichiometry in viroplasms appears to be distinct from the cytoplasmic transcript distribution, with the largest transcript being the most enriched in viroplasms, suggesting a selective RNA enrichment mechanism. While all 11 types of transcripts accumulate in viroplasms, their stoichiometry significantly varied between individual viroplasms. Accumulation of transcripts requires the presence of 3’ untranslated terminal regions and viroplasmic localisation of the viral polymerase VP1, consistent with the observed lack of polyadenylated transcripts in viroplasms. Our observations reveal similarities between viroplasms and other cytoplasmic RNP granules and identify viroplasmic proteins as drivers of viral RNA assembly during viroplasm formation.
    Keywords RNA viruses ; biomolecular condensates ; ribonucleoproteins ; RNA imaging ; Medicine ; R ; Science ; Q ; Biology (General) ; QH301-705.5
    Subject code 612
    Language English
    Publishing date 2023-01-01T00:00:00Z
    Publisher eLife Sciences Publications Ltd
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Effect of Power Ultrasonic on the Expansion of Fiber Strands

    Frederik Wilhelm / Sebastian Strauß / Raffael Weigant / Klaus Drechsler

    Journal of Composites Science, Vol 4, Iss 50, p

    2020  Volume 50

    Abstract: The present study investigates the effect of power ultrasonic on the expansion of fiber strands. A potential application of such expansion is in the production process known as closed injection pultrusion. The fiber strand in the pultrusion injection ... ...

    Abstract The present study investigates the effect of power ultrasonic on the expansion of fiber strands. A potential application of such expansion is in the production process known as closed injection pultrusion. The fiber strand in the pultrusion injection chamber is in compacted form, and so, any expansion of the fiber strand resulting from power ultrasonic should lead to improved fiber wetting. To investigate this, a wetted fiber strand was clamped on two sides and sonicated in the middle from below. The potential expansion of the fiber strand was visually determined through an observation window. The study concluded that power ultrasonic has a minimal to virtually negligible effect on the expansion of both glass and carbon fiber. The degree of expansion remains within a range of 3% maximum, with a standard deviation in the respective midpoint tests of up to 60% for glass fiber and over 100% for carbon fiber. This shows that the fibers are limited in their freedom of movement, and so no expansion can be achieved using power ultrasonic. A further increase in amplitude does not lead to any further expansion but to the destruction of the fibers.
    Keywords power ultrasonic ; expansion ; carbon fiber ; glass fiber ; pultrusion ; closed-injection pultrusion ; Technology ; T ; Science ; Q
    Subject code 621
    Language English
    Publishing date 2020-05-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Impaired Pain Processing at a Brainstem Level Is Involved in Maladaptive Neuroplasticity in Patients with Chronic Complex Regional Pain Syndrome

    Pauline Thoma / Nina Drämel / Matthias Grothe / Martin Lotze / Robert Fleischmann / Sebastian Strauss

    International Journal of Molecular Sciences, Vol 23, Iss 15368, p

    2022  Volume 15368

    Abstract: Neuroinflammatory mechanisms and maladaptive neuroplasticity underlie the progression of complex regional pain syndrome (CRPS), which is prototypical of central neuropathic pain conditions. While cortical maladaptive alterations are well described, ... ...

    Abstract Neuroinflammatory mechanisms and maladaptive neuroplasticity underlie the progression of complex regional pain syndrome (CRPS), which is prototypical of central neuropathic pain conditions. While cortical maladaptive alterations are well described, little is known about the contribution of the brainstem to the pathophysiology. This study investigates the role of pain-modulatory brainstem pathways in CRPS using the nociceptive blink reflex (nBR), which not only provides a direct read-out of brainstem excitability and habituation to painful stimuli but may also be suitable for use as a diagnostic biomarker for CRPS. Thirteen patients with CRPS and thirteen healthy controls (HCs) participated in this prospective case-control study investigating the polysynaptic trigemino-cervical (R2) nBR response. The R2 area and its habituation were assessed following repeated supraorbital electrical stimulation. Between-group comparisons included evaluations of diagnostic characteristics as a potential biomarker for the disease. Patients with CRPS showed a substantial decrease in habituation on the stimulated (Cohen’s d: 1.3; p = 0.012) and the non-stimulated side (Cohen’s d: 1.1; p = 0.04). This is the first study to reveal altered nBR habituation as a pathophysiological mechanism and potential diagnostic biomarker in CRPS. We confirmed previous findings of altered nBR excitability, but the diagnostic accuracy was inferior. Future studies should investigate the nBR as a marker of progression to central mechanisms in CRPS and as a biomarker to predict treatment response or prognosis.
    Keywords complex regional pain syndrome ; CRPS ; central sensitization ; brainstem ; blink reflex ; Biology (General) ; QH301-705.5 ; Chemistry ; QD1-999
    Subject code 610
    Language English
    Publishing date 2022-12-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: Experimental and Simulative Analysis of the Pressure Development in a Closed Injection Pultrusion Process with Multiple Chamber Geometries

    Sebastian Strauss / Frederik Wilhelm / Andreas Senz / Herbert Engelen / Simon Boysen / Niko Rilli / Alptekin Celik / Marcel Ratka / Christian Bonten

    Polymers, Vol 15, Iss 1544, p

    2023  Volume 1544

    Abstract: The use of innovative higher-performance highly reactive resin systems requires an enhancement of the established method of fiber impregnation (open bath) towards closed resin-injection pultrusion (CIP), due to the short pot life of the resin systems. ... ...

    Abstract The use of innovative higher-performance highly reactive resin systems requires an enhancement of the established method of fiber impregnation (open bath) towards closed resin-injection pultrusion (CIP), due to the short pot life of the resin systems. The result is that the open bath is developed into a closed injection and impregnation chamber (“ii-chamber”). In this study, three parameters—resin viscosity, opening angle and opening factor at the injection point on the ii-chamber—are varied, each in three stages. For each set of parameters, a pultrusion trial is conducted and the process pressures in the ii-chamber and pultrusion die measured. This enables direct feedback via the process conditions of the as yet uncured composite. The data obtained are used to validate a newly developed simulation model. The model is based on Darcy’s law, which has been extended to take fiber movement into account and thus represent the resulting pressure increase in the die. The flexible ii-chamber and die concept enhance our understanding of the processes taking place in the die system. The sensitivity of the process pressures can be shown for the three influencing variables. The experiment shows that of the three influencing variables investigated, viscosity has the greatest sensitivity to pressure development. In general, it can be said that over the length of the pultrusion die system, the pressure level increases across the three measuring points.
    Keywords pultrusion ; simulation ; closed injection pultrusion CIP ; aliphatic polyurethane ; thermoset ; pressure development ; Organic chemistry ; QD241-441
    Language English
    Publishing date 2023-03-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Comparison of the Processing of Epoxy Resins in Pultrusion with Open Bath Impregnation and Closed-Injection Pultrusion

    Sebastian Strauß / Andreas Senz / Jessica Ellinger

    Journal of Composites Science, Vol 3, Iss 3, p

    2019  Volume 87

    Abstract: In this study, the influence of the open bath and closed-injection pultrusion (CIP) processing methods of epoxy resins on the quality of glass fiber composites was investigated. In addition to the state-of-the-art epoxy resin system with long pot life, ... ...

    Abstract In this study, the influence of the open bath and closed-injection pultrusion (CIP) processing methods of epoxy resins on the quality of glass fiber composites was investigated. In addition to the state-of-the-art epoxy resin system with long pot life, new resin systems with short pot life have recently been developed. These systems require processing by closed-injection pultrusion. The epoxies with long pot life allow both processing variants. The experimental work was carried out with two types of injection and impregnation chambers (ii_chamber), namely with a conical and a teardrop design. Fully impregnated composites, which were used for further analyses, could be produced by using the conical ii_chamber. The composite properties of the open bath and the conical ii_chamber impregnation methods were compared. No significant influence on the bending stress could be determined; the interlaminar shear strength was up to 10% better with open bath impregnation than with ii_chamber. For the composites investigated, it was shown that the open bath and ii_chamber impregnation methods can be used to produce parts with partially comparable properties, as demonstrated for the epoxy formulation with long pot life. These results indicate that processing of epoxy systems with a short pot life is also possible by closed-injection pultrusion. Furthermore, the influence on the composite properties of the time interval between the mixing of an epoxy resin and processing in an open bath was investigated. No significant effect on the bending stress and interlaminar shear strength could be determined.
    Keywords pultrusion ; epoxy ; glass fibers ; thermoset ; closed-injection pultrusion ; open bath impregnation ; Technology ; T ; Science ; Q
    Subject code 600
    Language English
    Publishing date 2019-08-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Nanoscale organization of the endogenous ASC speck

    Ivo M. Glück / Grusha Primal Mathias / Sebastian Strauss / Virgile Rat / Irene Gialdini / Thomas Sebastian Ebert / Che Stafford / Ganesh Agam / Suliana Manley / Veit Hornung / Ralf Jungmann / Christian Sieben / Don C. Lamb

    iScience, Vol 26, Iss 12, Pp 108382- (2023)

    2023  

    Abstract: Summary: The NLRP3 inflammasome is a central component of the innate immune system. Its activation leads to formation of the ASC speck, a supramolecular assembly of the inflammasome adaptor protein ASC. Different models, based on ASC overexpression, have ...

    Abstract Summary: The NLRP3 inflammasome is a central component of the innate immune system. Its activation leads to formation of the ASC speck, a supramolecular assembly of the inflammasome adaptor protein ASC. Different models, based on ASC overexpression, have been proposed for the structure of the ASC speck. Using dual-color 3D super-resolution imaging (dSTORM and DNA-PAINT), we visualized the ASC speck structure following NLRP3 inflammasome activation using endogenous ASC expression. A complete structure was only obtainable by labeling with both anti-ASC antibodies and nanobodies. The complex varies in diameter between ∼800 and 1000 nm, and is composed of a dense core with emerging filaments. Dual-color confocal fluorescence microscopy indicated that the ASC speck does not colocalize with the microtubule-organizing center at late time points after Nigericin stimulation. From super-resolution images of whole cells, the ASC specks were sorted into a pseudo-time sequence indicating that they become denser but not larger during formation.
    Keywords Immunology ; Biotechnology ; Cell biology ; Science ; Q
    Language English
    Publishing date 2023-12-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article ; Online: Preventive treatment with CGRP monoclonal antibodies restores brain stem habituation deficits and excitability to painful stimuli in migraine

    Anne Thiele / Lara Klehr / Sebastian Strauß / Anselm Angermaier / Ulf Schminke / Martin Kronenbuerger / Steffen Naegel / Robert Fleischmann

    The Journal of Headache and Pain, Vol 22, Iss 1, Pp 1-

    results from a prospective case-control study

    2021  Volume 10

    Abstract: Abstract Background & Objectives Calcitonin gene-related peptide ligand/receptor (CGRP) antibodies effectively reduce headache frequency in migraine. It is understood that they act peripherally, which raises the question whether treatment merely ... ...

    Abstract Abstract Background & Objectives Calcitonin gene-related peptide ligand/receptor (CGRP) antibodies effectively reduce headache frequency in migraine. It is understood that they act peripherally, which raises the question whether treatment merely interferes with the last stage of headache generation or, alternatively, causes secondary adaptations in the central nervous system and might thus possess disease modifying potential. This study addresses this question by investigating the nociceptive blink reflex (nBR), which is closely tied to central disease activity, before and after treatment with CGRP antibodies. Methods We enrolled 22 patients suffering episodic migraine (21 female, 46.2 ± 13.8 years of age) and 22 age-/gender-matched controls. Patients received assessments of the nBR (R2 component, 10 trials, 6 stimuli/trial) before (V0) and three months (V3) after treatment with CGRP antibodies started, controls were assessed once. The R2 area (R2a) and habituation (R2h; gradient of R2a against stimulus order) of the stimulated/non-stimulated side (_s/_ns) following repeated supraorbital stimulation provide a direct readout of brainstem excitability and habituation as key mechanisms in migraine. Results All patients showed a substantial reduction of headache days/month (V0: 12.4±3.3, V3: 6.6 ± 4.9). R2a_s (Fglobal=5.86, p<0.001; block 1: R2a_s: -28%, p<0.001) and R2a_ns (Fglobal=8.22, p<0.001, block 1: R2a_ns: -22%, p=0.003) were significantly decreased, and R2h_ns was significantly enhanced (Fglobal=3.07, p<0.001; block 6: R2h_ns: r=-1.36, p=0.007) from V0 to V3. The global test for changes of R2h_s was non-significant (Fglobal=1.46, p=0.095). Changes of R2h significantly correlated with improvement of headache frequency (R2h_s, r=0.56, p=0.010; R2h_ns: r=0.45, p=0.045). None of the nBR parameters assessed at baseline predicted treatment response. Discussion We provide evidence that three months of treatment with CGRP antibodies restores brain stem responses to painful stimuli and thus might be considered disease modifying. The nociceptive blink reflex may provide a biomarker to monitor central disease activity. Future studies should evaluate the blink reflex as a clinical biomarker to predict treatment response at baseline and to establish the risk of relapse after treatment discontinuation. Trial registration This trial was prospectively registered at clinicaltrials.gov (ID: NCT04019496, date of registration: July 15, 2019).
    Keywords Migraine ; Headache ; Prevention ; Calcitonin gene-related peptide ; Antibodies ; Disease modifying drug ; Medicine ; R
    Subject code 610
    Language English
    Publishing date 2021-12-01T00:00:00Z
    Publisher BMC
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Direct supercritical angle localization microscopy for nanometer 3D superresolution

    Anindita Dasgupta / Joran Deschamps / Ulf Matti / Uwe Hübner / Jan Becker / Sebastian Strauss / Ralf Jungmann / Rainer Heintzmann / Jonas Ries

    Nature Communications, Vol 12, Iss 1, Pp 1-

    2021  Volume 9

    Abstract: Supercritical angle localisation microscopy (SALM) allows the z-positions of single fluorophores to be extracted from the intensity of supercritical angle fluorescence. Here the authors improve the z-resolution of SALM, and report nanometre isotropic ... ...

    Abstract Supercritical angle localisation microscopy (SALM) allows the z-positions of single fluorophores to be extracted from the intensity of supercritical angle fluorescence. Here the authors improve the z-resolution of SALM, and report nanometre isotropic localisation precision on DNA origami structures.
    Keywords Science ; Q
    Language English
    Publishing date 2021-02-01T00:00:00Z
    Publisher Nature Portfolio
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: High-precision estimation of emitter positions using Bayesian grouping of localizations

    Mohamadreza Fazel / Michael J. Wester / David J. Schodt / Sebastian Restrepo Cruz / Sebastian Strauss / Florian Schueder / Thomas Schlichthaerle / Jennifer M. Gillette / Diane S. Lidke / Bernd Rieger / Ralf Jungmann / Keith A. Lidke

    Nature Communications, Vol 13, Iss 1, Pp 1-

    2022  Volume 11

    Abstract: Single-molecule localization microscopy relies on stochastic blinking events, treated as independent events without assignment to a particular emitter. Here, BaGoL takes low precision localizations generated from multiple emitter blinkings during ... ...

    Abstract Single-molecule localization microscopy relies on stochastic blinking events, treated as independent events without assignment to a particular emitter. Here, BaGoL takes low precision localizations generated from multiple emitter blinkings during DNAPAINT and dSTORM and finds the underlying emitter positions with high precision.
    Keywords Science ; Q
    Language English
    Publishing date 2022-11-01T00:00:00Z
    Publisher Nature Portfolio
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: Single-Molecule Super-Resolution Microscopy Reveals Heteromeric Complexes of MET and EGFR upon Ligand Activation

    Marie-Lena I.E. Harwardt / Mark S. Schröder / Yunqing Li / Sebastian Malkusch / Petra Freund / Shashi Gupta / Nebojsa Janjic / Sebastian Strauss / Ralf Jungmann / Marina S. Dietz / Mike Heilemann

    International Journal of Molecular Sciences, Vol 21, Iss 2803, p

    2020  Volume 2803

    Abstract: Receptor tyrosine kinases (RTKs) orchestrate cell motility and differentiation. Deregulated RTKs may promote cancer and are prime targets for specific inhibitors. Increasing evidence indicates that resistance to inhibitor treatment involves receptor ... ...

    Abstract Receptor tyrosine kinases (RTKs) orchestrate cell motility and differentiation. Deregulated RTKs may promote cancer and are prime targets for specific inhibitors. Increasing evidence indicates that resistance to inhibitor treatment involves receptor cross-interactions circumventing inhibition of one RTK by activating alternative signaling pathways. Here, we used single-molecule super-resolution microscopy to simultaneously visualize single MET and epidermal growth factor receptor (EGFR) clusters in two cancer cell lines, HeLa and BT-20, in fixed and living cells. We found heteromeric receptor clusters of EGFR and MET in both cell types, promoted by ligand activation. Single-protein tracking experiments in living cells revealed that both MET and EGFR respond to their cognate as well as non-cognate ligands by slower diffusion. In summary, for the first time, we present static as well as dynamic evidence of the presence of heteromeric clusters of MET and EGFR on the cell membrane that correlates with the relative surface expression levels of the two receptors.
    Keywords receptor tyrosine kinases ; MET ; EGFR ; receptor cross-interaction ; single-molecule localization microscopy ; single-particle tracking ; Biology (General) ; QH301-705.5 ; Chemistry ; QD1-999
    Subject code 616
    Language English
    Publishing date 2020-04-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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