Publications by authors named "Dave J van den Heuvel"
The temperature-sensitive luminescence of nanoparticles enables their application as remote thermometers. The size of these nanothermometers makes them ideal to map temperatures with a high spatial resolution. However, high spatial resolution mapping of temperatures >373 K has remained challenging.
View Article and Find Full Text PDFIn this work, gold nanoparticles coated with a fluorescently labelled (rhodamine B) silica shell are presented as fiducial markers for correlative light and electron microscopy (CLEM). The synthesis of the particles is optimized to obtain homogeneous, spherical core-shell particles of arbitrary size. Next, particles labelled with different fluorophore densities are characterized to determine under which conditions bright and (photo)stable particles can be obtained.
View Article and Find Full Text PDFLabel-free nonlinear spectral imaging microscopy (NLSM) records two-photon-excited fluorescence emission spectra of endogenous fluorophores within the specimen. Here, NLSM is introduced as a novel, minimally invasive method to analyze the metabolic state of fungal hyphae by monitoring the autofluorescence of NAD(P)H and flavin adenine dinucleotide (FAD). Moreover, the presence of melanin was analyzed by NLSM.
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- Initial platelet arrest at arterial walls is initiated by glycoprotein Ibα binding to the A1 domain of von Willebrand factor, particularly at high shear forces.
- The interaction between glycoprotein Ibα and von Willebrand factor strengthens with increased fluid flow, and the study reveals that glycoprotein Ibα can form clusters on platelets under physiological conditions.
- These clusters enhance platelet interaction with von Willebrand factor and depend on the translocation of glycoprotein Ibα to lipid rafts, influenced by arachidonic acid and specific protein binding.
In neurons, the distinct molecular composition of axons and dendrites is established through polarized targeting mechanisms, but it is currently unclear how nonpolarized cargoes, such as mitochondria, become uniformly distributed over these specialized neuronal compartments. Here, we show that TRAK family adaptor proteins, TRAK1 and TRAK2, which link mitochondria to microtubule-based motors, are required for axonal and dendritic mitochondrial motility and utilize different transport machineries to steer mitochondria into axons and dendrites. TRAK1 binds to both kinesin-1 and dynein/dynactin, is prominently localized in axons, and is needed for normal axon outgrowth, whereas TRAK2 predominantly interacts with dynein/dynactin, is more abundantly present in dendrites, and is required for dendritic development.
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- Storing platelets at room temperature can lead to microbial risks and decreased functionality, causing high discard rates.
- Cold storage presents a solution but triggers rapid clearance of platelets post-transfusion due to changes in glycoprotein Ibα, which affects how platelets interact with other components in the blood.
- The study finds that by preventing the clustering of glycoprotein Ibα through specific blockades, the survival of cold-stored platelets can be improved without losing their ability to function effectively in clotting.
We report the synthesis of ultranarrow (Zn,Cd)Te/CdSe colloidal heteronanowires, using ZnTe magic size clusters as seeds. The wire formation starts with a partial Zn for Cd cation exchange, followed by self-organization into segmented heteronanowires. Further growth occurs by inclusion of CdSe.
View Article and Find Full Text PDFBiophysical imaging tools exploit several properties of fluorescence to map cellular biochemistry. However, the engineering of a cost-effective and user-friendly detection system for sensing the diverse properties of fluorescence is a difficult challenge. Here, we present a novel architecture for a spectrograph that permits integrated characterization of excitation, emission and fluorescence anisotropy spectra in a quantitative and efficient manner.
View Article and Find Full Text PDFThe study of lipoproteins, natural nanoparticles comprised of lipids and apolipoproteins that transport fats throughout the body, is of key importance to better understand, treat, and prevent cardiovascular disease. In the current study, we have developed a lipoprotein-based nanoparticle that consists of a quantum dot (QD) core and Cy5.5 labeled lipidic coating.
View Article and Find Full Text PDFThe current activation model of the EGF receptor (EGFR) predicts that binding of EGF results in dimerization and oligomerization of the EGFR, leading to the allosteric activation of the intracellular tyrosine kinase. Little is known about the regulatory mechanism of receptor oligomerization. In this study, we have employed FRET between identical fluorophores (homo-FRET) to monitor the dimerization and oligomerization state of the EGFR before and after receptor activation.
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- Fluorescent proteins, particularly EGFP, are crucial tools in cell biology but can face challenges like inefficient folding and aggregation, especially in prokaryotic cells.
- Enhanced variants SGFP2 and SBFP2 were developed to improve protein folding, fluorescence brightness, and photostability, showing significant advancements in brightness and stability compared to their predecessors.
- Experiments revealed that SGFP2 was 7-fold brighter than EGFP in bacteria and 1.7-fold brighter in mammalian cells, while SBFP2 was 16-fold and 3.7-fold brighter than EBFP in bacterial and mammalian cells, respectively, making them more effective for biological applications.