86 research outputs found

    Musical Multimodal Child Computer Interaction

    Get PDF
    In this project an interactive computer system is designed that envisions to contribute to young children's musical education. From literature, requirements for musical interaction were derived. In this paper these requirements and the design of the system are described

    Music is Movement: A Study into Aspects of Movement Representation of Musical Activities among Preschool Children in a Dutch Music Education Setting

    Get PDF
    To view the accompanying DVD material please request a copy of the hardbound thesis from the Library's main catalogue.Musical activities are at the centre of Music on the Lap, a Dutch approach to early childhood music education. The present study takes an in-depth look at the role of movement in these musical activities and thereby focuses on the representation of musical elements through movement. This study has among its aims the raising of more awareness for the conscious use of movement in early childhood music education. Departing from an embodied approach within an interpretative design, the premise of the current study is that movement should be considered an important form of kinaesthetic representation through which preschool children can come to understand and learn different aspects of music. The musical movement responses of children aged 18 to 36 months in a regular Music on the Lap setting were investigated. The musical movement behaviour of the children, during specific musical activities, was captured on DVD and the individual responses of 27 children were analysed. Interviews with the participating teacher provided important additional information. Through microanalysis of the children’s movements, the study arrived at a theoretical interpretation: movement responses to music can be considered enactive symbols, creating direct and indirect representations of musical characteristics. To further musical learning the movements should be firmly based in a temporal framework of aural and verbal connotations in order to stimulate purposeful movement responses. This temporal framework should be structured by the teacher through a process of appropriate movement models and verbal guidance to arrive at meaningful movement actions, which can consequently generate implicit and explicit musical kinaesthetic and musical representational knowledge. In this process the children are actively participating to construct with body and mind their own musical knowledge.Dutch Foundation Toddlers and Musi

    Combined TLR2 and TLR4 ligation in the context of bacterial or helminth extracts in human monocyte derived dendritic cells: molecular correlates for Th1/Th2 polarization

    Get PDF
    Background: Recognition of pathogens by dendritic cells (DCs) through interaction with pattern recognition receptors, including Toll like receptors (TLR), is crucial for the initiation of appropriate polarized T helper (Th) cell responses. Yet, the characteristics and differences in molecular profiles of DCs with different T cell polarizing capacities are still poorly defined. To address this issue, the molecular profile of human monocyte derived DCs was characterized after exposure to TLR4 ligand LPS in combination with the Th1 promoting bacterial extracts from Listeria monocytogenes and Escherichia coli or the Th2 promoting helminth derived phospholipids from Schistosoma mansoni and Ascaris lumbricoides, all with TLR2 activating capacity. Results: With regard to the signalling pathways activated upon exposure to LPS and the TLR2 activating compounds, we find that the ratio of activated Mitogen Activated Protein Kinases (MAPK) p-ERK/p-p38 is lower in DCs stimulated with the bacterial products compared to DCs stimulated with the helminth products, which correlates with the Th1 and Th2 polarizing capacity of these compounds. Furthermore, analysis of the mRNA expression levels of a set of 25 carefully selected genes potentially involved in modulation of T cell polarization revealed that the mRNA expression of notch ligand delta-4 and transcription factor c-fos are differentially regulated and show a strong correlation with Th1 and Th2 polarization, respectively. Conclusion: This study shows that combined TLR2 and TLR4 activation in the context of different antigen sources can induce very distinct molecular profiles in DCs and suggests that the Th1/Th2 polarizing capacity of compounds can be predicted with the molecular signature they induce in DCs

    Application of Optical Biosensors in Small-Molecule Screening Activities

    Get PDF
    The last two decades have seen remarkable progress and improvements in optical biosensor systems such that those are currently seen as an important and value-adding component of modern drug screening activities. In particular the introduction of microplate-based biosensor systems holds the promise to match the required throughput without compromising on data quality thus representing a sought-after complement to traditional fluidic systems. This article aims to highlight the application of the two most prominent optical biosensor technologies, namely surface plasmon resonance (SPR) and optical waveguide grating (OWG), in small-molecule screening and will present, review and discuss the advantages and disadvantages of different assay formats on these platforms. A particular focus will be on the specific advantages of the inhibition in solution assay (ISA) format in contrast to traditional direct binding assays (DBA). Furthermore we will discuss different application areas for both fluidic as well as plate-based biosensor systems by considering the individual strength of the platforms

    Ocellatin-PT antimicrobial peptides: high-resolution microscopy studies in antileishmania models and interactions with mimetic membrane systems

    Get PDF
    Although the mechanism of action of antimicrobial peptides (AMPs) is not clear, they can interact electrostatically with the cell membranes of microorganisms. New ocellatin-PT peptides were recently isolated from the skin secretion of Leptodactylus pustulatus. The secondary structure of these AMPs and their effect on Leishmania infantum cells, and on different lipid surface models was characterized in this work. The results showed that all ocellatin-PT peptides have an -helix structure and five of them (PT3, PT4, PT6 to PT8) have leishmanicidal activity; PT1 and PT2 affected the cellular morphology of the parasites and showed greater affinity for leishmania and bacteria-mimicking lipid membranes than for those of mammals. The results show selectivity of ocellatin-PTs to the membranes of microorganisms and the applicability of biophysical methods to clarify the interaction of AMPs with cell membranes.This work was partially supported by grants from INCT Nanobiotecnologia and PVE Project (MCT/CNPq), the Consejo Nacional de Investigaciones Cientificas y Técnicas (CONICET), and the Agencia Nacional de Promocion Científica y Tecnologica (ANPCyT). M.M.M.is a researcher at CONICET. This work has also been supported through project UID/MULTI/04378/2013-POCI/01/0145/FEDER/007728 with financial support from FCT/MEC through national funds and co-financed by FEDER, under the Partnership Agreement PT2020. Scanning electron microscopy was carried out at Centro de Materiais da Universidade do Porto, CEMUP. Peter Eaton is supported by a Ciência sem Fronteiras grant via CNPq, and his lab work is supported by financial support from FCT/MEC through national funds and co-financed by FEDER, under the partnership agreement PT2020. Alexandra Pl acido and Ana Georgina Gomes-Alves are grateful to FCT for their grants SFRH/BD/97995/2013 and SFRH/BD/93766/2013, financed by POPH–QREN–Tipologia 4.1–Formação Avançada, subsidized by Fundo Social Europeu and Ministério da Ciência, Tecnologia e Ensino Superior. Nuno Vale thanks Programa Operacional Regional do Norte (ON.2) and Faculdade de Ciências da Universidade do Porto (FCUP) for co-funding refurbishment of the Porto Peptide Synthesis Facility (POPUP) through operation NORTE-07-0162-FEDER000111. NV thanks Fundação para a Ciência e Tecnologia (FCT, Portugal) and FEDER (European Union) for funding through project grant IF/00092/2014. Work in AMT laboratory was supported by Project “NORTE-07-0124-FEDER-000002-Host-Pathogen Interactions” cofunded by Programa Operacional Regional do Norte under QREN, through FEDER and FCT. None of the funding bodies were involved in study design, in the collection, analysis and interpretation of data; in the writing of the report; or in the decision to submit the article for publication

    Replacement of Retinyl Esters by Polyunsaturated Triacylglycerol Species in Lipid Droplets of Hepatic Stellate Cells during Activation

    Get PDF
    Activation of hepatic stellate cells has been recognized as one of the first steps in liver injury and repair. During activation, hepatic stellate cells transform into myofibroblasts with concomitant loss of their lipid droplets (LDs) and production of excessive extracellular matrix. Here we aimed to obtain more insight in the dynamics and mechanism of LD loss. We have investigated the LD degradation processes in rat hepatic stellate cells in vitro with a combined approach of confocal Raman microspectroscopy and mass spectrometric analysis of lipids (lipidomics). Upon activation of the hepatic stellate cells, LDs reduce in size, but increase in number during the first 7 days, but the total volume of neutral lipids did not decrease. The LDs also migrate to cellular extensions in the first 7 days, before they disappear. In individual hepatic stellate cells. all LDs have a similar Raman spectrum, suggesting a similar lipid profile. However, Raman studies also showed that the retinyl esters are degraded more rapidly than the triacylglycerols upon activation. Lipidomic analyses confirmed that after 7 days in culture hepatic stellate cells have lost most of their retinyl esters, but not their triacylglycerols and cholesterol esters. Furthermore, we specifically observed a large increase in triacylglycerol-species containing polyunsaturated fatty acids, partly caused by an enhanced incorporation of exogenous arachidonic acid. These results reveal that lipid droplet degradation in activated hepatic stellate cells is a highly dynamic and regulated process. The rapid replacement of retinyl esters by polyunsaturated fatty acids in LDs suggests a role for both lipids or their derivatives like eicosanoids during hepatic stellate cell activation

    Enhanced Pro-Inflammatory Cytokine Responses following Toll-Like-Receptor Ligation in Schistosoma haematobium-Infected Schoolchildren from Rural Gabon

    Get PDF
    BACKGROUND: Schistosoma infection is thought to lead to down-regulation of the host's immune response. This has been shown for adaptive immune responses, but the effect on innate immunity, that initiates and shapes the adaptive response, has not been extensively studied. In a first study to characterize these responses, we investigated the effect of Schistosoma haematobium infection on cytokine responses of Gabonese schoolchildren to a number of Toll-like receptor (TLR) ligands. METHODOLOGY: Peripheral blood mononuclear cells (PBMCs) were collected from S. haematobium-infected and uninfected schoolchildren from the rural area of Zile in Gabon. PBMCs were incubated for 24 h and 72 h with various TLR ligands, as well as schistosomal egg antigen (SEA) and adult worm antigen (AWA). Pro-inflammatory TNF-alpha and anti-inflammatory/regulatory IL-10 cytokine concentrations were determined in culture supernatants. PRINCIPAL FINDINGS: Infected children produced higher adaptive IL-10 responses than uninfected children against schistosomal antigens (72 h incubation). On the other hand, infected children had higher TNF-alpha responses than uninfected children and significantly higher TNF-alpha to IL-10 ratios in response to FSL-1 and Pam3, ligands of TLR2/6 and TLR2/1 respectively. A similar trend was observed for the TLR4 ligand LPS while Poly(I:C) (Mda5/TLR3 ligand) did not induce substantial cytokine responses (24 h incubation). CONCLUSIONS: This pilot study shows that Schistosoma-infected children develop a more pro-inflammatory TLR2-mediated response in the face of a more anti-inflammatory adaptive immune response. This suggests that S. haematobium infection does not suppress the host's innate immune system in the context of single TLR ligation

    A comparison of five lipid extraction solvent systems for lipidomic studies of human LDL

    Get PDF
    Lipidome profile of fluids and tissues is a growing field as the role of lipids as signaling molecules is increasingly understood, relying on an effective and representative extraction of the lipids present. A number of solvent systems suitable for lipid extraction are commonly in use, though no comprehensive investigation of their effectiveness across multiple lipid classes has been carried out. To address this, human LDL from normolipidemic volunteers was used to evaluate five different solvent extraction protocols [Folch, Bligh and Dyer, acidified Bligh and Dyer, methanol (MeOH)-tert-butyl methyl ether (TBME), and hexane-isopropanol] and the extracted lipids were analyzed by LC-MS in a high-resolution instrument equipped with polarity switching. Overall, more than 350 different lipid species from 19 lipid subclasses were identified. Solvent composition had a small effect on the extraction of predominant lipid classes (triacylglycerides, cholesterol esters, and phosphatidylcholines). In contrast, extraction of less abundant lipids (phosphatidylinositols, lyso-lipids, ceramides, and cholesterol sulfates) was greatly influenced by the solvent system used. Overall, the Folch method was most effective for the extraction of a broad range of lipid classes in LDL, although the hexane-isopropanol method was best for apolar lipids and the MeOH-TBME method was suitable for lactosyl ceramides

    DC Priming by M. vaccae Inhibits Th2 Responses in Contrast to Specific TLR2 Priming and Is Associated with Selective Activation of the CREB Pathway

    Get PDF
    The environmental mycobacterium, M. vaccae has been used in mouse models to support the contemporary hygiene hypothesis that non-pathogenic microorganisms reduce allergy associated T helper (Th)2 responses and inflammatory diseases by augmenting regulatory T cells. However, data for human models and possible mechanisms are limited. We tested the effect of innate immune interactions between human DC and M. vaccae on DC-dependent T cell responses. M. vaccae activation of DC via Toll like receptor (TLR)2 was compared to a specific TLR2 ligand (Pam(3)CSK4) and alternative stimulation with a TLR4 ligand (LPS). M. vaccae induced DC dependent inhibition of Th2 responses, in contrast to Pam(3)CSK4, which had the opposite effect and LPS, which had no polarizing effect. DC maturation, gene expression and cytokine production, in response to each stimulus did not correlate with the specific functional effects. Comparable DC transcriptional responses to M. vaccae and Pam(3)CSK4 suggested that TLR2 mediated transcriptional regulation was not sufficient for inhibition of Th2 responses. Transcription factor enrichment analysis and assessment of signaling events, implicated a role for selective early activation of the CREB pathway by M. vaccae. Further study of the CREB pathway may provide novel insight into the molecular mechanisms of DC-dependent T cell polarization
    corecore