{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:52:31Z","timestamp":1760233951165,"version":"build-2065373602"},"reference-count":20,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,2,26]],"date-time":"2021-02-26T00:00:00Z","timestamp":1614297600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Cellular contacts modify the way cells migrate in a cohesive group with respect to a free single cell. The resulting motion is persistent and correlated, with cells\u2019 velocities self-aligning in time. The presence of a dense agglomerate of cells makes the application of single particle tracking techniques to define cells dynamics difficult, especially in the case of phase contrast images. Here, we propose an original pipeline for the analysis of phase contrast images of the wound healing scratch assay acquired in time-lapse, with the aim of extracting single particle trajectories describing the dynamics of the wound closure. In such an approach, the membrane of the cells at the border of the wound is taken as a unicum, i.e., the wound edge, and the dynamics is described by the stochastic motion of an ensemble of points on such a membrane, i.e., pseudo-particles. For each single frame, the pipeline of analysis includes: first, a texture classification for separating the background from the cells and for identifying the wound edge; second, the computation of the coordinates of the ensemble of pseudo-particles, chosen to be uniformly distributed along the length of the wound edge. We show the results of this method applied to a glioma cell line (T98G) performing a wound healing scratch assay without external stimuli. We discuss the efficiency of the method to assess cell motility and possible applications to other experimental layouts, such as single cell motion. The pipeline is developed in the Python language and is available upon request.<\/jats:p>","DOI":"10.3390\/e23030284","type":"journal-article","created":{"date-parts":[[2021,2,26]],"date-time":"2021-02-26T09:47:20Z","timestamp":1614332840000},"page":"284","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Study of Wound Healing Dynamics by Single Pseudo-Particle Tracking in Phase Contrast Images Acquired in Time-Lapse"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8872-6804","authenticated-orcid":false,"given":"Riccardo","family":"Scheda","sequence":"first","affiliation":[{"name":"DIFA-Physics and Astronomy Department, University of Bologna, Viale C. Berti Pichat 6\/2, 40127 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Silvia","family":"Vitali","sequence":"additional","affiliation":[{"name":"BCAM-Basque Center for Applied Mathematics, Alameda de Mazarredo 14, 48009 Bilbao, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2269-2338","authenticated-orcid":false,"given":"Enrico","family":"Giampieri","sequence":"additional","affiliation":[{"name":"eDIMESlab, Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Via Irnerio 49, 40126 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gianni","family":"Pagnini","sequence":"additional","affiliation":[{"name":"BCAM-Basque Center for Applied Mathematics, Alameda de Mazarredo 14, 48009 Bilbao, Spain"},{"name":"Ikerbasque-Basque Foundation for Science, Plaza Euskadi 5, 48009 Bilbao, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Isabella","family":"Zironi","sequence":"additional","affiliation":[{"name":"DIFA-Physics and Astronomy Department, University of Bologna, Viale C. Berti Pichat 6\/2, 40127 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"362","DOI":"10.1038\/nrc1075","article-title":"Tumour-cell invasion and migration: Diversity and escape mechanisms","volume":"3","author":"Friedl","year":"2003","journal-title":"Nat. Rev. Cancer"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"407","DOI":"10.1146\/annurev.cellbio.042308.113231","article-title":"Collective cell migration","volume":"25","author":"Rorth","year":"2009","journal-title":"Annu. Rev. Cell Dev. Biol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"743","DOI":"10.1038\/nrm.2017.98","article-title":"Mechanobiology of collective cell behaviours","volume":"18","author":"Ladoux","year":"2017","journal-title":"Nat. Rev. Mol. 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Available online: https:\/\/www.scipy.org\/."}],"container-title":["Entropy"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1099-4300\/23\/3\/284\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T05:29:25Z","timestamp":1760160565000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1099-4300\/23\/3\/284"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,2,26]]},"references-count":20,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2021,3]]}},"alternative-id":["e23030284"],"URL":"https:\/\/doi.org\/10.3390\/e23030284","relation":{},"ISSN":["1099-4300"],"issn-type":[{"type":"electronic","value":"1099-4300"}],"subject":[],"published":{"date-parts":[[2021,2,26]]}}}