{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T01:57:27Z","timestamp":1777514247455,"version":"3.51.4"},"reference-count":26,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,2,5]],"date-time":"2021-02-05T00:00:00Z","timestamp":1612483200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012550","name":"Nemzeti Kutat\u00e1si, Fejleszt\u00e9si \u00e9s Innovaci\u00f3s Alap","doi-asserted-by":"publisher","award":["FK_131916"],"award-info":[{"award-number":["FK_131916"]}],"id":[{"id":"10.13039\/501100012550","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005881","name":"Emberi Eroforr\u00e1sok Miniszt\u00e9riuma","doi-asserted-by":"publisher","award":["EFOP-3.6.3-VEKOP-16-2017-00009"],"award-info":[{"award-number":["EFOP-3.6.3-VEKOP-16-2017-00009"]}],"id":[{"id":"10.13039\/501100005881","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011019","name":"Nemzeti Kutat\u00e1si Fejleszt\u00e9si \u00e9s Innov\u00e1ci\u00f3s Hivatal","doi-asserted-by":"publisher","award":["\u00daNKP- 20-4-II-SE-7"],"award-info":[{"award-number":["\u00daNKP- 20-4-II-SE-7"]}],"id":[{"id":"10.13039\/501100011019","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011019","name":"Nemzeti Kutat\u00e1si Fejleszt\u00e9si \u00e9s Innov\u00e1ci\u00f3s Hivatal","doi-asserted-by":"publisher","award":["\u00daNKP-19-3-I-SE-78"],"award-info":[{"award-number":["\u00daNKP-19-3-I-SE-78"]}],"id":[{"id":"10.13039\/501100011019","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["1.1.1.2\/16\/I\/001"],"award-info":[{"award-number":["1.1.1.2\/16\/I\/001"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Keratins are one of the main fluorophores of the skin. Keratinization disorders can lead to alterations in the optical properties of the skin. We set out to investigate a rare form of keratinopathic ichthyosis caused by KRT1 mutation with two different optical imaging methods. We used a newly developed light emitting diode (LED) based device to analyze autofluorescence signal at 405 nm excitation and diffuse reflectance at 526 nm in vivo. Mean autofluorescence intensity of the hyperkeratotic palmar skin was markedly higher in comparison to the healthy control (162.35 vs. 51.14). To further assess the skin status, we examined samples from affected skin areas ex vivo by nonlinear optical microscopy. Two-photon excited fluorescence and second-harmonic generation can visualize epidermal keratin and dermal collagen, respectively. We were able to visualize the structure of the epidermis and other skin changes caused by abnormal keratin formation. Taken together, we were able to show that such imaging modalities are useful for the diagnosis and follow-up of keratinopathic diseases.<\/jats:p>","DOI":"10.3390\/s21041105","type":"journal-article","created":{"date-parts":[[2021,2,5]],"date-time":"2021-02-05T08:33:48Z","timestamp":1612514028000},"page":"1105","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Visualization of Keratin with Diffuse Reflectance and Autofluorescence Imaging and Nonlinear Optical Microscopy in a Rare Keratinopathic Ichthyosis"],"prefix":"10.3390","volume":"21","author":[{"given":"P\u00e1lma","family":"Anker","sequence":"first","affiliation":[{"name":"Department of Dermatology, Venereology and Dermatooncology, Semmelweis University, 1083 Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Luca","family":"F\u00e9s\u0171s","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Venereology and Dermatooncology, Semmelweis University, 1083 Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9947-1755","authenticated-orcid":false,"given":"Norbert","family":"Kiss","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Venereology and Dermatooncology, Semmelweis University, 1083 Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Judit","family":"Noll","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Szent Janos Hospital, 1125 Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2266-8533","authenticated-orcid":false,"given":"Krisztina","family":"Becker","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Venereology and Dermatooncology, Semmelweis University, 1083 Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Enik\u0151","family":"Kuroli","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Venereology and Dermatooncology, Semmelweis University, 1083 Budapest, Hungary"},{"name":"1st Department of Pathology and Experimental Cancer Research, Semmelweis University, 1083 Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bal\u00e1zs","family":"Mayer","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Venereology and Dermatooncology, Semmelweis University, 1083 Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Szabolcs","family":"Bozs\u00e1nyi","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Venereology and Dermatooncology, Semmelweis University, 1083 Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kende","family":"L\u0151rincz","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Venereology and Dermatooncology, Semmelweis University, 1083 Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ilze","family":"Lihacova","sequence":"additional","affiliation":[{"name":"Institute of Atomic Physics and Spectroscopy, University of Latvia, LV-1586 Riga, Latvia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4178-895X","authenticated-orcid":false,"given":"Alexey","family":"Lihachev","sequence":"additional","affiliation":[{"name":"Institute of Atomic Physics and Spectroscopy, University of Latvia, LV-1586 Riga, Latvia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marta","family":"Lange","sequence":"additional","affiliation":[{"name":"Institute of Atomic Physics and Spectroscopy, University of Latvia, LV-1586 Riga, Latvia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Norbert","family":"Wikonk\u00e1l","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Venereology and Dermatooncology, Semmelweis University, 1083 Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3126-096X","authenticated-orcid":false,"given":"M\u00e1rta","family":"Medvecz","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Venereology and Dermatooncology, Semmelweis University, 1083 Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"528","DOI":"10.1111\/ced.13800","article-title":"Novel and recurrent mutations in keratin 1 cause epidermolytic ichthyosis and palmoplantar keratoderma","volume":"44","author":"Smith","year":"2019","journal-title":"Clin. 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