Thermal fluctuations of grafted microtubules provide evidence of a length-dependent persistence length.
AuthorsPampaloni F, Lattanzi G, Jonás A, Surrey T, Frey E, Florin EL
JournalProc Natl Acad Sci U S A
PubMed ID16801537
'Microtubules are hollow cylindrical structures that constitute one of the three major classes of cytoskeletal filaments. On the mesoscopic length scale of a cell, their material properties are characterized by a single stiffness parameter, the persistence length l(p). Its value, in general, depends on the microscopic interactions between the constituent ... More
Gridlock signalling pathway fashions the first embryonic artery.
AuthorsZhong TP, Childs S, Leu JP, Fishman MC
JournalNature
PubMed ID11700560
'Arteries and veins are morphologically, functionally and molecularly very different, but how this distinction is established during vasculogenesis is unknown. Here we show, by lineage tracking in zebrafish embryos, that angioblast precursors for the trunk artery and vein are spatially mixed in the lateral posterior mesoderm. Progeny of each angioblast, ... More
Why molecules move along a temperature gradient.
AuthorsDuhr S, Braun D
JournalProc Natl Acad Sci U S A
PubMed ID17164337
'Molecules drift along temperature gradients, an effect called thermophoresis, the Soret effect, or thermodiffusion. In liquids, its theoretical foundation is the subject of a long-standing debate. By using an all-optical microfluidic fluorescence method, we present experimental results for DNA and polystyrene beads over a large range of particle sizes, salt ... More
Rapid transport of large polymeric nanoparticles in fresh undiluted human mucus.
AuthorsLai SK, O'Hanlon DE, Harrold S, Man ST, Wang YY, Cone R, Hanes J
JournalProc Natl Acad Sci U S A
PubMed ID17244708
'Nanoparticles larger than the reported mesh-pore size range (10-200 nm) in mucus have been thought to be much too large to undergo rapid diffusional transport through mucus barriers. However, large nanoparticles are preferred for higher drug encapsulation efficiency and the ability to provide sustained delivery of a wider array of ... More
Real-time multiple particle tracking of gene nanocarriers in complex biological environments.
AuthorsLai SK, Hanes J,
JournalMethods Mol Biol
PubMed ID18470640
'Complex biological fluids, such as the vast and molecularly crowded cell cytoplasm and the highly viscoelastic mucus that protects many entry ways to the body, pose significant barriers to efficient gene delivery. Understanding the dynamics of gene carriers in such environments allows insight that leads to rational improvements in gene ... More
A murine scavenger receptor MARCO recognizes polystyrene nanoparticles.
AuthorsKanno S, Furuyama A, Hirano S,
JournalToxicol Sci
PubMed ID17361018
'Recent toxicological studies indicate that nanoparticles or ultrafine particles (< 100 nm) are more toxic than fine particles (< 2 microm) because of their greater surface area. It is well known that alveolar macrophages play an important role in the first defense against various environmental particles and microorganisms. This is ... More
Cholesterol-dependent partitioning of PtdIns(4,5)P2 into membrane domains by the N-terminal fragment of NAP-22 (neuronal axonal myristoylated membrane protein of 22 kDa).
AuthorsEpand RM, Vuong P, Yip CM, Maekawa S, Epand RF
JournalBiochem J
PubMed ID14989697
A myristoylated peptide corresponding to the N-terminus of NAP-22 (neuronal axonal myristoylated membrane protein of 22 kDa) causes the quenching of the fluorescence of BODIPY-TMR-labelled PtdIns(4,5) P2 in bilayers of 1-palmitoyl-2-oleoyl phosphatidylcholine containing 40 mol% cholesterol and 0.1 mol% BODIPY-PtdIns(4,5)2. Both fluorescence spectroscopy and total internal reflectance fluorescence microscopy revealed ... More
Immune-like phagocyte activity in the social amoeba.
AuthorsChen G, Zhuchenko O, Kuspa A,
JournalScience
PubMed ID17673666
Social amoebae feed on bacteria in the soil but aggregate when starved to form a migrating slug. We describe a previously unknown cell type in the social amoeba, which appears to provide detoxification and immune-like functions and which we term sentinel (S) cells. S cells were observed to engulf bacteria ... More
Macrophage-enriched myristoylated alanine-rich C kinase substrate and its phosphorylation is required for the phorbol ester-stimulated diffusion of beta 2 integrin molecules.
AuthorsZhou X, Li J
JournalJ Biol Chem
PubMed ID10779523
An early event of beta(2) integrin activation is the increased diffusion rate of this molecule on the cell surface, thereby providing integrin molecules with a better chance to meet the ligands. The activation of protein kinase C (PKC) stimulates integrin diffusion by releasing the cytoskeletal constraint on integrin molecules. We ... More
Isolation of serotype-specific antibodies against dengue virus non-structural protein 1 using phage display and application in a multiplexed serotyping assay.
AuthorsLebani K, Jones ML, Watterson D, Ranzoni A, Traves RJ, Young PR, Mahler SM
JournalPLoS One
PubMed ID28683141
The multidimensional nature of dengue virus (DENV) infections, which can be caused by four distinct serotypes of the virus, complicates the sensitivity of assays designed for the diagnosis of infection. Different viral markers can be optimally detected at different stages of infection. Of particular clinical importance is the early identification ... More