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Lux F, Calikoglu A, Klusmann C, Hillenbrand M, Ataman Ç. 3D nanoprinted catadioptric fiber sensor for dual-axis distance measurement during vitrectomy. APPLIED OPTICS 2024; 63:2806-2814. [PMID: 38856375 DOI: 10.1364/ao.518950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2024] [Accepted: 03/08/2024] [Indexed: 06/11/2024]
Abstract
Retinal damage is a common intraoperative complication during vitrectomy, caused by a complex interplay between the suction of the vitrectome, the cut- and aspiration rate, and the distance of the instrument to the retina. To control this last factor, we developed two miniaturized fiber-optic distance sensors based on low-coherence interferometry for direct integration into the vitrectome. Both sensors have a diameter of 250 µm, which makes them compatible with a 25G vitrectome. The first sensor measures distance in the lateral direction. The second sensor is capable of simultaneously measuring distance in both the lateral and the axial direction. Axial and lateral directions correspond to the direction of the cutter port of the vitrectome and the direction along the vitrectome's shaft, respectively. In both sensors, a free-form mirror deflects and focuses the beam in the lateral direction. In the dual-axis distance sensor, an additional lens is integrated into the free-form mirror for distance measurement in the axial direction. The beam-shaping micro-optics at the tip of the sensor fibers were fabricated through two-photon polymerization and are selectively gold coated for increased reflectivity of the mirror. Distance measurements were successfully demonstrated in artificial samples and in ex vivo pig eyes with a back-end that uses a current-tuned VCSEL as a swept-source. We experimentally demonstrate that the complete sensor system can attain a S N R max of up to 80 dB. The small dimensions of the developed sensors make them a potential solution for various other medical applications.
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Cecchini A, Cornelison DDW. Eph/Ephrin-Based Protein Complexes: The Importance of cis Interactions in Guiding Cellular Processes. Front Mol Biosci 2022; 8:809364. [PMID: 35096972 PMCID: PMC8793696 DOI: 10.3389/fmolb.2021.809364] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 12/21/2021] [Indexed: 12/13/2022] Open
Abstract
Although intracellular signal transduction is generally represented as a linear process that transmits stimuli from the exterior of a cell to the interior via a transmembrane receptor, interactions with additional membrane-associated proteins are often critical to its success. These molecules play a pivotal role in mediating signaling via the formation of complexes in cis (within the same membrane) with primary effectors, particularly in the context of tumorigenesis. Such secondary effectors may act to promote successful signaling by mediating receptor-ligand binding, recruitment of molecular partners for the formation of multiprotein complexes, or differential signaling outcomes. One signaling family whose contact-mediated activity is frequently modulated by lateral interactions at the cell surface is Eph/ephrin (EphA and EphB receptor tyrosine kinases and their ligands ephrin-As and ephrin-Bs). Through heterotypic interactions in cis, these molecules can promote a diverse range of cellular activities, including some that are mutually exclusive (cell proliferation and cell differentiation, or adhesion and migration). Due to their broad expression in most tissues and their promiscuous binding within and across classes, the cellular response to Eph:ephrin interaction is highly variable between cell types and is dependent on the cellular context in which binding occurs. In this review, we will discuss interactions between molecules in cis at the cell membrane, with emphasis on their role in modulating Eph/ephrin signaling.
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Affiliation(s)
- Alessandra Cecchini
- Division of Biological Sciences, University of Missouri, Columbia, MO, United States
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - D. D. W. Cornelison
- Division of Biological Sciences, University of Missouri, Columbia, MO, United States
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
- *Correspondence: D. D. W. Cornelison,
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Díaz Lantada A, Mazarío Picazo N, Guttmann M, Wissmann M, Schneider M, Worgull M, Hengsbach S, Rupp F, Bade K, Plaza GR. Soft-Lithography of Polyacrylamide Hydrogels Using Microstructured Templates: Towards Controlled Cell Populations on Biointerfaces. MATERIALS (BASEL, SWITZERLAND) 2020; 13:E1586. [PMID: 32235578 PMCID: PMC7177395 DOI: 10.3390/ma13071586] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 03/17/2020] [Accepted: 03/25/2020] [Indexed: 02/08/2023]
Abstract
Polyacrylamide hydrogels are interesting materials for studying cells and cell-material interactions, thanks to the possibility of precisely adjusting their stiffness, shear modulus and porosity during synthesis, and to the feasibility of processing and manufacturing them towards structures and devices with controlled morphology and topography. In this study a novel approach, related to the processing of polyacrylamide hydrogels using soft-lithography and employing microstructured templates, is presented. The main novelty relies on the design and manufacturing processes used for achieving the microstructured templates, which are transferred by soft-lithography, with remarkable level of detail, to the polyacrylamide hydrogels. The conceived process is demonstrated by patterning polyacrylamide substrates with a set of vascular-like and parenchymal-like textures, for controlling cell populations. Final culture of amoeboid cells, whose dynamics is affected by the polyacrylamide patterns, provides a preliminary validation of the described strategy and helps to discuss its potentials.
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Affiliation(s)
- Andrés Díaz Lantada
- Product Development Laboratory, Mechanical Engineering Department, Universidad Politécnica de Madrid, c/José Gutiérrez Abascal 2, 28006 Madrid, Spain;
| | - Noelia Mazarío Picazo
- Product Development Laboratory, Mechanical Engineering Department, Universidad Politécnica de Madrid, c/José Gutiérrez Abascal 2, 28006 Madrid, Spain;
- Centre for Biomedical Technology, Universidad Politécnica de Madrid, Parque Científico y Tecnológico de la UPM, Crta. M40, km. 38, 28223 Pozuelo de Alarcón, Madrid, Spain;
| | - Markus Guttmann
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany; (M.G.); (M.W.); (M.S.); (M.W.); (S.H.); (F.R.); (K.B.)
| | - Markus Wissmann
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany; (M.G.); (M.W.); (M.S.); (M.W.); (S.H.); (F.R.); (K.B.)
| | - Marc Schneider
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany; (M.G.); (M.W.); (M.S.); (M.W.); (S.H.); (F.R.); (K.B.)
| | - Matthias Worgull
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany; (M.G.); (M.W.); (M.S.); (M.W.); (S.H.); (F.R.); (K.B.)
| | - Stefan Hengsbach
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany; (M.G.); (M.W.); (M.S.); (M.W.); (S.H.); (F.R.); (K.B.)
| | - Florian Rupp
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany; (M.G.); (M.W.); (M.S.); (M.W.); (S.H.); (F.R.); (K.B.)
| | - Klaus Bade
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany; (M.G.); (M.W.); (M.S.); (M.W.); (S.H.); (F.R.); (K.B.)
| | - Gustavo R. Plaza
- Centre for Biomedical Technology, Universidad Politécnica de Madrid, Parque Científico y Tecnológico de la UPM, Crta. M40, km. 38, 28223 Pozuelo de Alarcón, Madrid, Spain;
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