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  1. Article ; Online: Fiber finding algorithm using stepwise tracing to identify biopolymer fibers in noisy 3D images.

    Rossen, Ninna Struck / Kyrsting, Anders / Giaccia, Amato J / Erler, Janine Terra / Oddershede, Lene Broeng

    Biophysical journal

    2021  Volume 120, Issue 18, Page(s) 3860–3868

    Abstract: We present a novel fiber finding algorithm (FFA) that will permit researchers to detect and return traces of individual biopolymers. Determining the biophysical properties and structural cues of biopolymers can permit researchers to assess the ... ...

    Abstract We present a novel fiber finding algorithm (FFA) that will permit researchers to detect and return traces of individual biopolymers. Determining the biophysical properties and structural cues of biopolymers can permit researchers to assess the progression and severity of disease. Confocal microscopy images are a useful method for observing biopolymer structures in three dimensions, but their utility for identifying individual biopolymers is impaired by noise inherent in the acquisition process, including convolution from the point spread function (PSF). The new, iterative FFA we present here 1) measures a microscope's PSF and uses it as a metric for identifying fibers against the background; 2) traces each fiber within a cone angle; and 3) blots out the identified trace before identifying another fiber. Blotting out the identified traces in each iteration allows the FFA to detect and return traces of single fibers accurately and efficiently-even within fiber bundles. We used the FFA to trace unlabeled collagen type I fibers-a biopolymer used to mimic the extracellular matrix in in vitro cancer assays-imaged by confocal reflectance microscopy in three dimensions, enabling quantification of fiber contour length, persistence length, and three-dimensional (3D) mesh size. Based on 3D confocal reflectance microscopy images and the PSF, we traced and measured the fibers to confirm that colder gelation temperatures increased fiber contour length, persistence length, and 3D mesh size-thereby demonstrating the FFA's use in quantifying biopolymers' structural and physical cues from noisy microscope images.
    MeSH term(s) Algorithms ; Biopolymers ; Collagen Type I ; Imaging, Three-Dimensional ; Microscopy, Confocal
    Chemical Substances Biopolymers ; Collagen Type I
    Language English
    Publishing date 2021-08-17
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 218078-9
    ISSN 1542-0086 ; 0006-3495
    ISSN (online) 1542-0086
    ISSN 0006-3495
    DOI 10.1016/j.bpj.2021.08.017
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Fractionated photothermal therapy in a murine tumor model: comparison with single dose.

    Simón, Marina / Norregaard, Kamilla / Jørgensen, Jesper Tranekjær / Oddershede, Lene Broeng / Kjaer, Andreas

    International journal of nanomedicine

    2019  Volume 14, Page(s) 5369–5379

    Abstract: Purpose: ...

    Abstract Purpose:
    MeSH term(s) Animals ; Cell Line, Tumor ; Disease Models, Animal ; Dose-Response Relationship, Radiation ; Female ; Glycerol/chemistry ; Gold/chemistry ; Hot Temperature ; Hyperthermia, Induced ; Infrared Rays ; Mice, Inbred BALB C ; Nanoshells/chemistry ; Nanoshells/ultrastructure ; Neoplasms/pathology ; Neoplasms/therapy ; Phototherapy ; Positron-Emission Tomography ; Silicon Dioxide/chemistry ; Treatment Outcome ; Tumor Burden
    Chemical Substances Gold (7440-57-5) ; Silicon Dioxide (7631-86-9) ; Glycerol (PDC6A3C0OX)
    Language English
    Publishing date 2019-07-18
    Publishing country New Zealand
    Document type Comparative Study ; Journal Article
    ZDB-ID 2364941-0
    ISSN 1178-2013 ; 1176-9114
    ISSN (online) 1178-2013
    ISSN 1176-9114
    DOI 10.2147/IJN.S205409
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Filopodia rotate and coil by actively generating twist in their actin shaft.

    Leijnse, Natascha / Barooji, Younes Farhangi / Arastoo, Mohammad Reza / Sønder, Stine Lauritzen / Verhagen, Bram / Wullkopf, Lena / Erler, Janine Terra / Semsey, Szabolcs / Nylandsted, Jesper / Oddershede, Lene Broeng / Doostmohammadi, Amin / Bendix, Poul Martin

    Nature communications

    2022  Volume 13, Issue 1, Page(s) 1636

    Abstract: Filopodia are actin-rich structures, present on the surface of eukaryotic cells. These structures play a pivotal role by allowing cells to explore their environment, generate mechanical forces or perform chemical signaling. Their complex dynamics ... ...

    Abstract Filopodia are actin-rich structures, present on the surface of eukaryotic cells. These structures play a pivotal role by allowing cells to explore their environment, generate mechanical forces or perform chemical signaling. Their complex dynamics includes buckling, pulling, length and shape changes. We show that filopodia additionally explore their 3D extracellular space by combining growth and shrinking with axial twisting and buckling. Importantly, the actin core inside filopodia performs a twisting or spinning motion which is observed for a range of cell types spanning from earliest development to highly differentiated tissue cells. Non-equilibrium physical modeling of actin and myosin confirm that twist is an emergent phenomenon of active filaments confined in a narrow channel which is supported by measured traction forces and helical buckles that can be ascribed to accumulation of sufficient twist. These results lead us to conclude that activity induced twisting of the actin shaft is a general mechanism underlying fundamental functions of filopodia.
    MeSH term(s) Actin Cytoskeleton/metabolism ; Actins/metabolism ; Motion ; Myosins/metabolism ; Pseudopodia/metabolism
    Chemical Substances Actins ; Myosins (EC 3.6.4.1)
    Language English
    Publishing date 2022-03-28
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-022-28961-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Non-invasive Early Response Monitoring of Nanoparticle-assisted Photothermal Cancer Therapy Using

    Jørgensen, Jesper Tranekjær / Norregaard, Kamilla / Simón Martín, Marina / Oddershede, Lene Broeng / Kjaer, Andreas

    Nanotheranostics

    2018  Volume 2, Issue 3, Page(s) 201–210

    Abstract: Rationale: ...

    Abstract Rationale:
    Language English
    Publishing date 2018
    Publishing country Australia
    Document type Journal Article
    ISSN 2206-7418
    ISSN (online) 2206-7418
    DOI 10.7150/ntno.24478
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Friction-limited cell motility in confluent monolayer tissue.

    Christensen, Amalie / West, Ann-Katrine Vrans / Wullkopf, Lena / Terra Erler, Janine / Oddershede, Lene Broeng / Mathiesen, Joachim

    Physical biology

    2018  Volume 15, Issue 6, Page(s) 66004

    Abstract: Mechanical forces are important factors in the development, coordination and collective motion of cells. Based on a continuum-scale model, we consider the influence of substrate friction on cell motility in confluent living tissue. We test our model on ... ...

    Abstract Mechanical forces are important factors in the development, coordination and collective motion of cells. Based on a continuum-scale model, we consider the influence of substrate friction on cell motility in confluent living tissue. We test our model on the experimental data of endothelial and cancer cells. In contrast to the commonly used drag friction, we find that solid friction best captures the cell speed distribution. From our model, we quantify a number of measurable physical tissue parameters, such as the ratio between the viscosity and substrate friction.
    MeSH term(s) Animals ; Cell Line ; Cell Line, Tumor ; Cell Movement ; Endothelial Cells/physiology ; Friction ; Human Umbilical Vein Endothelial Cells ; Humans ; MCF-7 Cells ; Models, Molecular ; Viscosity
    Language English
    Publishing date 2018-07-25
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2133216-2
    ISSN 1478-3975 ; 1478-3967
    ISSN (online) 1478-3975
    ISSN 1478-3967
    DOI 10.1088/1478-3975/aacedc
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Dynamics of cancerous tissue correlates with invasiveness.

    West, Ann-Katrine Vransø / Wullkopf, Lena / Christensen, Amalie / Leijnse, Natascha / Tarp, Jens Magelund / Mathiesen, Joachim / Erler, Janine Terra / Oddershede, Lene Broeng

    Scientific reports

    2017  Volume 7, Page(s) 43800

    Abstract: Two of the classical hallmarks of cancer are uncontrolled cell division and tissue invasion, which turn the disease into a systemic, life-threatening condition. Although both processes are studied, a clear correlation between cell division and motility ... ...

    Abstract Two of the classical hallmarks of cancer are uncontrolled cell division and tissue invasion, which turn the disease into a systemic, life-threatening condition. Although both processes are studied, a clear correlation between cell division and motility of cancer cells has not been described previously. Here, we experimentally characterize the dynamics of invasive and non-invasive breast cancer tissues using human and murine model systems. The intrinsic tissue velocities, as well as the divergence and vorticity around a dividing cell correlate strongly with the invasive potential of the tissue, thus showing a distinct correlation between tissue dynamics and aggressiveness. We formulate a model which treats the tissue as a visco-elastic continuum. This model provides a valid reproduction of the cancerous tissue dynamics, thus, biological signaling is not needed to explain the observed tissue dynamics. The model returns the characteristic force exerted by an invading cell and reveals a strong correlation between force and invasiveness of breast cancer cells, thus pinpointing the importance of mechanics for cancer invasion.
    MeSH term(s) Algorithms ; Animals ; Breast Neoplasms/pathology ; Cell Line, Tumor ; Cell Movement ; Humans ; Kinetics ; MCF-7 Cells ; Mammary Neoplasms, Animal/pathology ; Mice ; Microscopy, Phase-Contrast ; Models, Biological ; Neoplasm Invasiveness ; Time-Lapse Imaging/methods
    Language English
    Publishing date 2017-03-06
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/srep43800
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Book ; Online: Filopodia rotate and coil by actively generating twist in their actin shaft

    Leijnse, Natascha / Barooji, Younes Farhangi / Arastoo, Mohammad Reza / Sønder, Stine Lauritzen / Verhagen, Bram / Wullkopf, Lena / Erler, Janine Terra / Semsey, Szabolcs / Nylandsted, Jesper / Oddershede, Lene Broeng / Doostmohammadi, Amin / Bendix, Poul Martin

    2021  

    Abstract: Filopodia are actin-rich structures, present on the surface of practically every known eukaryotic cell. These structures play a pivotal role in specific cell-cell and cell-matrix interactions by allowing cells to explore their environment, generate ... ...

    Abstract Filopodia are actin-rich structures, present on the surface of practically every known eukaryotic cell. These structures play a pivotal role in specific cell-cell and cell-matrix interactions by allowing cells to explore their environment, generate mechanical forces, perform chemical signaling, or convey signals via intercellular tunneling nano-bridges. The dynamics of filopodia appear quite complex as they exhibit a rich behavior of buckling, pulling, length and shape changes. Here, we show that filopodia additionally explore their 3D extracellular space by combining growth and shrinking with axial twisting and buckling of their actin rich core. Importantly, the actin core inside filopodia performs a twisting or spinning motion which is observed for a range of highly distinct and cognate cell types spanning from earliest development to highly differentiated tissue cells. Non-equilibrium physical modeling of actin and myosin confirm that twist, and hence rotation, is an emergent phenomenon of active filaments confined in a narrow channel which points to a generic mechanism present in all cells. Our measurements confirm that filopodia exert traction forces and form helical buckles in a range of different cell types that can be ascribed to accumulation of sufficient twist. These results lead us to conclude that activity induced twisting of the actin shaft is a general mechanism underlying fundamental functions of filopodia.
    Keywords Physics - Biological Physics ; Condensed Matter - Soft Condensed Matter
    Subject code 612
    Publishing date 2021-11-25
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Visco-elastic membrane tethers extracted from Escherichia coli by optical tweezers.

    Jauffred, Liselotte / Callisen, Thomas Hønger / Oddershede, Lene Broeng

    Biophysical journal

    2007  Volume 93, Issue 11, Page(s) 4068–4075

    Abstract: Tethers were created between a living Escherichia coli bacterium and a bead by unspecifically attaching the bead to the outer membrane and pulling it away using optical tweezers. Upon release, the bead returned to the bacterium, thus showing the ... ...

    Abstract Tethers were created between a living Escherichia coli bacterium and a bead by unspecifically attaching the bead to the outer membrane and pulling it away using optical tweezers. Upon release, the bead returned to the bacterium, thus showing the existence of an elastic tether between the bead and the bacterium. These tethers can be tens of microns long, several times the bacterial length. Using mutants expressing different parts of the outer membrane structure, we have shown that an intact core lipopolysaccharide is a necessary condition for tether formation, regardless of whether the beads were uncoated polystyrene or beads coated with lectin. A physical characterization of the tethers has been performed yielding visco-elastic tether force-extension relationships: for first pull tethers, a spring constant of 10-12 pN/mum describes the tether visco-elasticity, for subsequent pulls the spring constant decreases to 6-7 pN/mum, and typical relaxation timescales of hundreds of seconds are observed. Studies of tether stability in the presence of proteases, lipases, and amylases lead us to propose that the extracted tether is primarily composed of the asymmetric lipopolysaccharide containing bilayer of the outer membrane. This unspecific tethered attachment mechanism could be important in the initiation of bacterial adhesion.
    MeSH term(s) Bacterial Adhesion/physiology ; Cell Surface Extensions/chemistry ; Cell Surface Extensions/physiology ; Elasticity ; Escherichia coli/chemistry ; Escherichia coli/physiology ; Optical Tweezers ; Viscosity
    Language English
    Publishing date 2007-12-01
    Publishing country United States
    Document type Journal Article
    ZDB-ID 218078-9
    ISSN 1542-0086 ; 0006-3495
    ISSN (online) 1542-0086
    ISSN 0006-3495
    DOI 10.1529/biophysj.107.103861
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Book ; Thesis: Scaling phenomena in the fracture of solids and in the behavior of liquid under applied fields

    Oddershede, Lene Broeng

    1998  

    Author's details Lene Broeng Oddershede
    Language English
    Size 116 S
    Document type Book ; Thesis
    Thesis / German Habilitation thesis Univ., Ph. D. Thesis--Odensen, 1998
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  10. Article ; Online: Arachidonic acid randomizes endothelial cell motion and regulates adhesion and migration.

    Rossen, Ninna Struck / Hansen, Anker Jon / Selhuber-Unkel, Christine / Oddershede, Lene Broeng

    PloS one

    2011  Volume 6, Issue 9, Page(s) e25196

    Abstract: Cell adhesion and migration are essential for the evolution, organization, and repair of living organisms. An example of a combination of these processes is the formation of new blood vessels (angiogenesis), which is mediated by a directed migration and ... ...

    Abstract Cell adhesion and migration are essential for the evolution, organization, and repair of living organisms. An example of a combination of these processes is the formation of new blood vessels (angiogenesis), which is mediated by a directed migration and adhesion of endothelial cells (ECs). Angiogenesis is an essential part of wound healing and a prerequisite of cancerous tumor growth. We investigated the effect of the amphiphilic compound arachidonic acid (AA) on EC adhesion and migration by combining live cell imaging with biophysical analysis methods. AA significantly influenced both EC adhesion and migration, in either a stimulating or inhibiting fashion depending on AA concentration. The temporal evolution of cell adhesion area was well described by a two-phase model. In the first phase, the spreading dynamics were independent of AA concentration. In the latter phase, the spreading dynamics increased at low AA concentrations and decreased at high AA concentrations. AA also affected EC migration; though the instantaneous speed of individual cells remained independent of AA concentration, the individual cells lost their sense of direction upon addition of AA, thus giving rise to an overall decrease in the collective motion of a confluent EC monolayer into vacant space. Addition of AA also caused ECs to become more elongated, this possibly being related to incorporation of AA in the EC membrane thus mediating a change in the viscosity of the membrane. Hence, AA is a promising non-receptor specific regulator of wound healing and angiogenesis.
    MeSH term(s) Animals ; Arachidonic Acid/pharmacology ; Cell Adhesion/drug effects ; Cell Movement/drug effects ; Cells, Cultured ; Endothelial Cells/cytology ; Endothelial Cells/drug effects ; Endothelium, Vascular/cytology ; Swine
    Chemical Substances Arachidonic Acid (27YG812J1I)
    Language English
    Publishing date 2011-09-23
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0025196
    Database MEDical Literature Analysis and Retrieval System OnLINE

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