{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,13]],"date-time":"2026-11-13T04:46:43Z","timestamp":1794545203580,"version":"4.9.1"},"reference-count":58,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,2,10]],"date-time":"2022-02-10T00:00:00Z","timestamp":1644451200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: The dental pulp stem cells are highly proliferative and can differentiate into various cell types, including endothelial cells. We aimed to evaluate the ultrastructural characteristics of the human dental pulp cells of the permanent frontal teeth. Materials and Methods: Human adult bioptic dental pulp was collected from n = 10 healthy frontal teeth of five adult patients, prior to prosthetic treatments for aesthetic purposes. Tissues were examined under transmission electron microscopy. Results: We identified cells with a peculiar trait: giant nucleoli resembling intranuclear endoplasmic reticulum, which mimicked extrusion towards the cytoplasm. These were either partly embedded within the nuclei, the case in which their adnuclear side was coated by marginal heterochromatin and the abnuclear side was coated by a thin rim of ribosomes, or were apparently isolated from the nuclei, while still being covered by ribosomes. Conclusions: Similar electron microscopy features were previously reported in the human endometrium, as nucleolar channel system; or R-Rings induced by Nopp140. To our knowledge, this is the first report of extruded nucleolar structure in the dental pulp. Moreover, the aspect of giant extruded nucleoli was not previously reported in any human cell type, although similar evidence was gathered in other species as well as in plants.<\/jats:p>","DOI":"10.3390\/medicina58020260","type":"journal-article","created":{"date-parts":[[2022,2,10]],"date-time":"2022-02-10T04:42:27Z","timestamp":1644468147000},"page":"260","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Extruded Nucleoli of Human Dental Pulp Cells"],"prefix":"10.3390","volume":"58","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8723-0540","authenticated-orcid":false,"given":"Mugurel Constantin","family":"Rusu","sequence":"first","affiliation":[{"name":"Division of Anatomy, Faculty of Dental Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandra Diana","family":"Vrapciu","sequence":"additional","affiliation":[{"name":"Division of Anatomy, Faculty of Dental Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8051-1166","authenticated-orcid":false,"given":"Mihnea Ioan","family":"Nicolescu","sequence":"additional","affiliation":[{"name":"Division of Histology, Faculty of Dental Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"},{"name":"Laboratory of Radiobiology, \u201cVictor Babe\u0219\u201d National Institute of Pathology, 050096 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mihai Dragomir","family":"Stoenescu","sequence":"additional","affiliation":[{"name":"Research Department, \u201cDr. Carol Davila\u201d Central Military Emergency Hospital, 010825 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adelina Maria","family":"Jianu","sequence":"additional","affiliation":[{"name":"Department of Anatomy, Faculty of Medicine, \u201cVictor Babe\u015f\u201d University of Medicine and Pharmacy, 300041 Timi\u015foara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rodica","family":"Lighezan","sequence":"additional","affiliation":[{"name":"Department of Histology, Faculty of Medicine, \u201cVictor Babe\u015f\u201d University of Medicine and Pharmacy, 300041 Timi\u015foara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roxana","family":"Oancea","sequence":"additional","affiliation":[{"name":"Department of Preventive and Community Dentistry, Faculty of Dental Medicine, \u201cVictor Babe\u015f\u201d University of Medicine and Pharmacy, 300041 Timi\u015foara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vasile Sorin","family":"M\u0103noiu","sequence":"additional","affiliation":[{"name":"Department of Cellular and Molecular Biology, National Institute of Research and Development for Biological Sciences, 060031 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4130-9402","authenticated-orcid":false,"given":"Sorin","family":"Hostiuc","sequence":"additional","affiliation":[{"name":"Division of Legal Medicine, Faculty of Dental Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 020021 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,10]]},"reference":[{"key":"ref_1","first-page":"3343","article-title":"Dental pulp of the third molar: A new source of pluripotent-like stem cells","volume":"125","author":"Atari","year":"2012","journal-title":"J. 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