2,909 research outputs found

    Endogenous, or therapeutically induced, type I interferon responses differentially modulate Th1/Th17-mediated autoimmunity in the CNS

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    Different viruses trigger pattern recognition receptor systems, such as Toll-like receptors or cytosolic RIG-I like helicases (RLH), and thus induce early type I interferon (IFN-I) responses. Such responses may confer protection until adaptive immunity is activated to an extent that the pathogen can be eradicated. Interestingly, the same innate immune mechanisms that are relevant for early pathogen defense have a role in ameliorating experimental autoimmune encephalomyelitis (EAE), a rodent model of human multiple sclerosis. We and others found that mice devoid of a component of the IFN-I receptor (Ifnar1−/−) showed significantly enhanced autoimmune disease of the central nervous system (CNS). A detailed analysis revealed that in wild-type mice IFN-I triggering of myeloid cells was instrumental in reducing brain damage. A more recent study indicated that similar to Ifnar1−/− mice, RLH-signaling-deficient mice showed enhanced autoimmune disease of the CNS as well. Moreover, when peripherally treated with synthetic RLH ligands wild-type animals with EAE disease showed reduced clinical scores. Under such conditions, IFN-I receptor triggering of dendritic cells had a crucial role. The therapeutic effect of treatment with RLH ligands was associated with negative regulation of Th1 and Th17 T-cell responses within the CNS. These experiments are consistent with the hypothesis that spatiotemporal conditions of, and cell types involved in, disease-ameliorating IFN-I responses differ significantly, depending on whether they were endogenously induced in the context of EAE pathogenesis within the CNS or upon therapeutic RLH triggering in the periphery. It is attractive to speculate that RLH triggering represents a new strategy to treat multiple sclerosis by stimulating endogenous immunoregulatory IFN-I responses

    Dihedral symmetry of periodic chain: quantization and coherent states

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    Our previous work on quantum kinematics and coherent states over finite configuration spaces is extended: the configuration space is, as before, the cyclic group Z_n of arbitrary order n=2,3,..., but a larger group - the non-Abelian dihedral group D_n - is taken as its symmetry group. The corresponding group related coherent states are constructed and their overcompleteness proved. Our approach based on geometric symmetry can be used as a kinematic framework for matrix methods in quantum chemistry of ring molecules.Comment: 13 pages; minor changes of the tex

    From learning to creativity: Identifying the behavioural and neural correlates of learning to predict human judgements of musical creativity

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    Human creativity is strongly linked to acquired knowledge. However, to date learning a new musical style and subsequent creativity have largely been studied in isolation. We introduced a novel experimental paradigm combining behavioural, electrophysiological, and computational methods, to examine the neural correlates of unfamiliar music learning, and to investigate how neural and computational measures can predict human creativity. We investigated music learning by training non-musicians (N = 40) on an artificial music grammar. Participants’ knowledge of the grammar was tested before and after three training sessions by assessing explicit recognition of the notes of the grammar, while additionally recording EEG. After each training session, participants created their own musical compositions, which were later evaluated by human experts. A computational model of auditory expectation was used to quantify the statistical properties of both the grammar and the compositions. Results showed that participants successfully learned the grammar. This was also reflected in the N100, P200, and P3a components, which were higher in response to incorrect than correct notes. Delta band power in response to grammatical notes during first exposure to the grammar positively correlated with learning, suggesting a potential encoding neural mechanism. On the other hand, better learning was associated with lower alpha and higher beta band power after training, potentially reflecting neural mechanisms of retrieval. Importantly, learning was a significant predictor of creativity, as judged by experts. There was also an inverted U-shaped relationship between percentage of correct intervals and creativity, as compositions with an intermediate proportion of correct intervals were associated with the highest creativity. Finally, the P200 in response to incorrect notes was predictive of creativity, suggesting a link between the neural correlates of learning, and creativity. Overall, our findings shed light on the neural mechanisms of learning an unfamiliar music grammar, as well as offering contributions to the associations between learning measures and human evaluation of creativity

    Flow across microvessel walls through the endothelial surface glycocalyx and the interendothelial cleft

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    A mathematical model is presented for steady fluid flow across microvessel walls through a serial pathway consisting of the endothelial surface glycocalyx and the intercellular cleft between adjacent endothelial cells, with junction strands and their discontinuous gaps. The three-dimensional flow through the pathway from the vessel lumen to the tissue space has been computed numerically based on a Brinkman equation with appropriate values of the Darcy permeability. The predicted values of the hydraulic conductivity Lp, defined as the ratio of the flow rate per unit surface area of the vessel wall to the pressure drop across it, are close to experimental measurements for rat mesentery microvessels. If the values of the Darcy permeability for the surface glycocalyx are determined based on the regular arrangements of fibres with 6nm radius and 8nm spacing proposed recently from the detailed structural measurements, then the present study suggests that the surface glycocalyx could be much less resistant to flow compared to previous estimates by the one-dimensional flow analyses, and the intercellular cleft could be a major determinant of the hydraulic conductivity of the microvessel wall

    Investigation of USP30 inhibition to enhance Parkin-mediated mitophagy: tools and approaches

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    Mitochondrial dysfunction is implicated in Parkinson disease (PD). Mutations in Parkin, an E3 ubiquitin ligase, can cause juvenile-onset Parkinsonism probably through impairment of mitophagy. Inhibition of the de-ubiquitinating enzyme USP30 may counter this effect to enhance mitophagy. Using different tools and cellular approaches, we wanted to independently confirm this claimed role for USP30. Pharmacological characterization of additional tool compounds that selectively inhibit USP30 are reported. The consequence of USP30 inhibition by these compounds, siRNA knockdown and overexpression of dominant-negative USP30 in the mitophagy pathway in different disease-relevant cellular models was explored. Knockdown and inhibition of USP30 showed increased p-Ser65-ubiquitin levels and mitophagy in neuronal cell models. Furthermore, patient-derived fibroblasts carrying pathogenic mutations in Parkin showed reduced p-Ser65-ubiquitin levels compared to wild-type cells, levels that could be restored using either USP30 inhibitor or dominant-negative USP30 expression. Our data provide additional support for USP30 inhibition as a regulator of the mitophagy pathway

    Consensus-Based Core Set of Outcome Measures for Clinical Motor Rehabilitation After Stroke—A Delphi Study

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    Introduction: Outcome measures are key to tailor rehabilitation goals to the stroke patient's individual needs and to monitor poststroke recovery. The large number of available outcome measures leads to high variability in clinical use. Currently, an internationally agreed core set of motor outcome measures for clinical application is lacking. Therefore, the goal was to develop such a set to serve as a quality standard in clinical motor rehabilitation poststroke. / Methods: Outcome measures for the upper and lower extremities, and activities of daily living (ADL)/stroke-specific outcomes were identified and presented to stroke rehabilitation experts in an electronic Delphi study. In round 1, clinical feasibility and relevance of the outcome measures were rated on a 7-point Likert scale. In round 2, those rated at least as “relevant” and “feasible” were ranked within the body functions, activities, and participation domains of the International Classification of Functioning, Disability, and Health (ICF). Furthermore, measurement time points poststroke were indicated. In round 3, answers were reviewed in reference to overall results to reach final consensus. / Results: In total, 119 outcome measures were presented to 33 experts from 18 countries. The recommended core set includes the Fugl–Meyer Motor Assessment and Action Research Arm Test for the upper extremity section; the Fugl–Meyer Motor Assessment, 10-m Walk Test, Timed-Up-and-Go, and Berg Balance Scale for the lower extremity section; and the National Institutes of Health Stroke Scale, and Barthel Index or Functional Independence Measure for the ADL/stroke-specific section. The Stroke Impact Scale was recommended spanning all ICF domains. Recommended measurement time points are days 2 ± 1 and 7; weeks 2, 4, and 12; 6 months poststroke and every following 6th month. / Discussion and Conclusion: Agreement was found upon a set of nine outcome measures for application in clinical motor rehabilitation poststroke, with seven measurement time points following the stages of poststroke recovery. This core set was specifically developed for clinical practice and distinguishes itself from initiatives for stroke rehabilitation research. The next challenge is to implement this clinical core set across the full stroke care continuum with the aim to improve the transparency, comparability, and quality of stroke rehabilitation at a regional, national, and international level

    Plasma exchange for primary autoimmune autonomic failure

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    We report on a patient with long-standing severe autonomic failure that affected his sympathetic and parasympathetic nervous systems. Antibodies against the ganglionic acetylcholine receptors were detected in the serum. Removal of the antibodies by means of plasma exchange resulted in a dramatic clinical improvement
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