1,720,969 research outputs found
Assembly of organotypic tissue models using narrative and structural-based tissue engineering approaches
No full textTissue engineering stands at the intersection of biology, (bio)materials science, and engineering, offering unprecedented opportunities to fabricate functional tissues that replicate the complexity of their natural counterparts. This field has evolved significantly since its inception, driven by the need for better regenerative therapies, improved disease models and reliable platforms for drug testing. By mimicking the native cellular microenvironment, tissue engineering enables the development of biomimetic structures that can restore lost function, enhance our understanding of physiological processes, and accelerate biomedical innovations. Despite considerable advancements, significant challenges remain in fabrication of large, structurally complex and physiologically relevant tissues. The integration
of multiple cell types, the formation of vascular networks and the precise control of both spatial organization and differentiation are critical hurdles that must be overcome to achieve clinically relevant tissue constructs. Addressing these
challenges requires a multidisciplinary approach that combines state-of-the-art biofabrication techniques with an in-depth understanding of cell biology. This thesis explores innovative approaches to tissue engineering upon integrating
emerging biofabrication tools and fundamental principles of mechanobiology. By
leveraging ultrasound-based assembly techniques and microgel-enabled modular biofabrication, this work introduces novel methodologies to guide tissue structure and function with high precision, with the
ultimate goal to enhance the scalability,
reproducibility and translational potential of engineered tissues
Assembly of organotypic tissue models using narrative and structural-based tissue engineering approaches
No full textTissue engineering stands at the intersection of biology, (bio)materials science, and engineering, offering unprecedented opportunities to fabricate functional tissues that replicate the complexity of their natural counterparts. This field has evolved significantly since its inception, driven by the need for better regenerative therapies, improved disease models and reliable platforms for drug testing. By mimicking the native cellular microenvironment, tissue engineering enables the development of biomimetic structures that can restore lost function, enhance our understanding of physiological processes, and accelerate biomedical innovations. Despite considerable advancements, significant challenges remain in fabrication of large, structurally complex and physiologically relevant tissues. The integration
of multiple cell types, the formation of vascular networks and the precise control of both spatial organization and differentiation are critical hurdles that must be overcome to achieve clinically relevant tissue constructs. Addressing these
challenges requires a multidisciplinary approach that combines state-of-the-art biofabrication techniques with an in-depth understanding of cell biology. This thesis explores innovative approaches to tissue engineering upon integrating
emerging biofabrication tools and fundamental principles of mechanobiology. By
leveraging ultrasound-based assembly techniques and microgel-enabled modular biofabrication, this work introduces novel methodologies to guide tissue structure and function with high precision, with the
ultimate goal to enhance the scalability,
reproducibility and translational potential of engineered tissues
Nanocapsules with stimuli-responsive moieties for controlled release employing light and enzymatic triggers
No full textThe development of stimuli-responsive nanomaterials, that possess tailored functional properties for the release of specific compounds, is of particular interest. To this extent, controlling the release of molecules at the desired target is an important parameter to regulate chemical and/or biological reactions at a more profound level in a wide variety of applications. In the present work, we report on the development of dual-responsive thiourethane-urethane nanocapsules synthesizedviaan interfacial polymerization reaction executed at the droplet interface using the inverse miniemulsion technique. Evidenceviamorphological and controlled release investigations indicate that our nanocapsules are able to encapsulate hydrophilic compounds with high efficiency in their aqueous core and allow for its selective release upon exposure to UV light and the enzyme esterase. Moreover, we demonstrate the efficient encapsulation of the fragrance molecule geranyl acetate and the anticancer drug doxorubicin. For the latter, we demonstrate its apoptotic effect after being released in MCF 7 breast cancer cells. Overall, these nanocapsules can be used for a wide variety of applications where a selective release of the payload is desired.S. S. is an SB PhD Fellow at the FWO (Research Foundation Flanders). S. K. P. acknowledges BOF funding from Hasselt University. This work is supported by Hasselt University and the Research Foundation Flanders (FWO Vlaanderen; Hercules project AUHL/15/2 - GOH3816N). The authors are thankful to Prof. M. Van Bael for access to the DLS device.Pramanik, SK; Ethirajan, A (corresponding author), Hasselt Univ, Inst Mat Res IMO, Wetenschapspk 1 & Agoralaan D, B-3590 Diepenbeek, Belgium; IMEC, Associated Lab IMOMEC, Wetenschapspk 1, B-3590 Diepenbeek, Belgium;
CSIR Cent Salt & Marine Chem Res Inst, Bhavnagar 364002, Gujarat, India.
[email protected]; [email protected]
PEGylating poly(p-phenylene vinylene)-based bioimaging nanoprobes
No full textHypothesis: Conjugated polymer nanoparticles (CNPs) have attracted considerable attention within bioimaging due to their excellent optical properties and biocompatibility. However, unspecific adsorption of proteins hampers their effective use as advanced bioimaging probes. Controlled methodologies made possible tailor-made functional poly(p-phenylene vinylene), enabling one-pot synthesis of CNPs containing functional surface groups. Hence, it should be feasible to PEGylate these CNPs to tune the uptake by cell lines representative for the brain without imparting their optical properties. Experiments: CNPs consisting of the statistical copolymer 2-(50-methoxycarbonylpentyloxy)-5-methoxy-1,4-phenylenevinylene and poly(2-methoxy-5-(30,70-dimethoxyoctyloxy)-1,4-phenylenevinylene) were fabricated by miniemulsion solvent evaporation technique. Surface carboxylic acid groups were used to covalently attach amine-terminated polyethylene glycol (PEG) of different molecular weights. We investigated the effect of grafting CNPs with PEG chains on their intrinsic optical properties, protein adsorption behavior and uptake by representative brain cell lines. Findings: PEGylation did not affect the optical properties and biocompatibility of our CNPs. Moreover, a significant decrease in protein corona formation and unspecific uptake in central nervous system cell lines, depending on PEG chain length, was observed. This is the first report indicating that PEGylation does not affect the CNPs role as excellent bioimaging tools and can be adapted to tune biological interactions with brain cells. (C) 2020 Elsevier Inc. All rights reserved.Support for confocal microscopy was given by Prof. dr. Marcel Ameloot and Dr. Hannelore Bove. Cells were kindly provided by Prof. dr. Annelies Bronckaers, Dr. Jo Mailleux and dra. Jasmine Vanmol. Technical support was given by Huguette Penxten, Christel Bocken and Erik Royackers. Dr. Neomy Zaquen is acknowledged for the synthesis of the conjugated polymers. MP is grateful for funding from the IWT (Agentschap voor Innovatie door Wetenschap en Technologie). SS is an SB PhD Fellow at the Research Foundation Flanders (FWO). The work was funded by the Belgian Charcot Foundation. TJ is grateful for funding from the FWO in the form of an Odysseus grant. This work was supported by Hasselt University and the Research Foundation Flanders (FWO Vlaanderen; Hercules project AUHL/15/2 -GOH3816N). Additional support from BELSPO in the form of the interuniversity attraction pole (IAP) program P7/05: Functional Supramolecular Systems is kindly acknowledged. We further acknowledge the Hercules Foundation for the project (LC-MS@UHasselt: Linear Trap QuadrupoleOrbitrap mass spectrometer.Ethirajan, A (corresponding author), Hasselt Univ, Inst Mat Res, Wetenschapspk 1, B-3590 Diepenbeek, Belgium.
[email protected]
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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