{"id":{"repo_id":"bradford","oai_identifier":"oai:bradscholars.brad.ac.uk:10454/16064"},"canonical_url":"https://search.dev.ndltd.org/etd/bradford/oai:bradscholars.brad.ac.uk:10454/16064","repository":{"repo_id":"bradford","name":"University of Bradford","base_url":"https://bradscholars.brad.ac.uk/oai/request"},"display":{"title":"Photo-biomodulation of human skin fibroblast sub-populations: a systematic approach for the optimization of optical treatment parameters","abstract":"The thesis presents a rational path for the optimization of the selection of optical treatment parameters in photobiomodulation of human skin fibroblasts. The project begins with an extensive analysis of 90 bibliographic reports in photobiomodulation published between 1985 and 2015, and revealed major inconsistencies in optical parameters selected for clinical applications. Seeking greater clarity for optimal parameter choice, a systematic approach to disentangle the multiple factors underpinning the response of human dermal fibroblasts in vitro to visible and near-infra red (NIR) light was employed. Light-based devices were constructed to specifically and systematically screen the optical parameter window (i.e. wavelength, irradiance and dose) observed in literature. Additionally, critical culture and treatment conditions that have dramatic impact on the outcome of specific light treatment of these human skin dermal cells were identified. In particular, environmental oxygen concentration, cell confluency and serum concentration were all found to have a great effect on the response of dermal fibroblasts to light. In parallel, the induction of reactive oxygen species (ROS) by short visible wavelengths on two dermal fibroblast sub-populations or lineage, reticular and papillary, was monitored by live-cell imaging. The ROS species were found to be created in or close to mitochondria. Lastly, gene expression studies revealed a strong impact of short visible wavelengths, as compared to long and NIR wavelengths on both subpopulations of human dermal fibroblasts. In particular, blue light (450 nm) specifically down-regulated proliferation, metabolism and protein synthesis molecular pathways. At the protein level, 450-nm light inhibited the production of procollagen I in human reticular and papillary fibroblasts in a dose-dependent manner. Gene expression results were in agreement i.e., the same light parameter down-regulated collagen fiber genes, integrins and up-regulated collagenase MMP1. This thesis concludes with a chapter presenting a characterization of the accuracy of a potential translation tool for the prediction of optical photon density inside human skin.","abstract_html":"The thesis presents a rational path for the optimization of the selection of optical treatment parameters in photobiomodulation of human skin fibroblasts. The project begins with an extensive analysis of 90 bibliographic reports in photobiomodulation published between 1985 and 2015, and revealed major inconsistencies in optical parameters selected for clinical applications. Seeking greater clarity for optimal parameter choice, a systematic approach to disentangle the multiple factors underpinning the response of human dermal fibroblasts in vitro to visible and near-infra red (NIR) light was employed. Light-based devices were constructed to specifically and systematically screen the optical parameter window (i.e. wavelength, irradiance and dose) observed in literature. Additionally, critical culture and treatment conditions that have dramatic impact on the outcome of specific light treatment of these human skin dermal cells were identified. In particular, environmental oxygen concentration, cell confluency and serum concentration were all found to have a great effect on the response of dermal fibroblasts to light. In parallel, the induction of reactive oxygen species (ROS) by short visible wavelengths on two dermal fibroblast sub-populations or lineage, reticular and papillary, was monitored by live-cell imaging. The ROS species were found to be created in or close to mitochondria. Lastly, gene expression studies revealed a strong impact of short visible wavelengths, as compared to long and NIR wavelengths on both subpopulations of human dermal fibroblasts. In particular, blue light (450 nm) specifically down-regulated proliferation, metabolism and protein synthesis molecular pathways. At the protein level, 450-nm light inhibited the production of procollagen I in human reticular and papillary fibroblasts in a dose-dependent manner. Gene expression results were in agreement i.e., the same light parameter down-regulated collagen fiber genes, integrins and up-regulated collagenase MMP1. This thesis concludes with a chapter presenting a characterization of the accuracy of a potential translation tool for the prediction of optical photon density inside human skin.","abstract_has_math":false,"creators":["Mignon, Charles"],"institution":"University of Bradford","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Tobin, Desmond J.","Uzunbajakava, N.E.","Botchkareva, Natalia V.","Zeitouny, M."],"committee_chairs":[],"committee_members":[],"year":2017,"date_issued":"2017","date_published":"2017","updated_at":"2026-07-24T01:14:08Z","subjects":["Photobiomodulation","Skin","Light","Subpopulations","Design of experiment","Monte Carlo method","Human dermal fibroblasts (HDF)"],"languages":["en"],"rights":["\"Creative
The University of Bradford theses are licenced under a Creative Commons Licence."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10454/16064","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Tobin, Desmond J.","Uzunbajakava, N.E.","Botchkareva, Natalia V.","Zeitouny, M."]},{"key":"dc:creator","label":"Author","values":["Mignon, Charles"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2018-05-30T09:36:03Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2018-05-30T09:36:03Z"]},{"key":"dc:date.issued","label":"Date","values":["2017"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Centre for Skin Science, Faculty of Life Sciences"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Bradford"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["doctoral"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["PhD"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Photobiomodulation","Skin","Light","Subpopulations","Design of experiment","Monte Carlo method","Human dermal fibroblasts (HDF)"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["\"Creative
The University of Bradford theses are licenced under a Creative Commons Licence."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10454/16064"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The thesis presents a rational path for the optimization of the selection of optical treatment parameters in photobiomodulation of human skin fibroblasts. The project begins with an extensive analysis of 90 bibliographic reports in photobiomodulation published between 1985 and 2015, and revealed major inconsistencies in optical parameters selected for clinical applications. Seeking greater clarity for optimal parameter choice, a systematic approach to disentangle the multiple factors underpinning the response of human dermal fibroblasts in vitro to visible and near-infra red (NIR) light was employed. Light-based devices were constructed to specifically and systematically screen the optical parameter window (i.e. wavelength, irradiance and dose) observed in literature. Additionally, critical culture and treatment conditions that have dramatic impact on the outcome of specific light treatment of these human skin dermal cells were identified. In particular, environmental oxygen concentration, cell confluency and serum concentration were all found to have a great effect on the response of dermal fibroblasts to light. In parallel, the induction of reactive oxygen species (ROS) by short visible wavelengths on two dermal fibroblast sub-populations or lineage, reticular and papillary, was monitored by live-cell imaging. The ROS species were found to be created in or close to mitochondria. Lastly, gene expression studies revealed a strong impact of short visible wavelengths, as compared to long and NIR wavelengths on both subpopulations of human dermal fibroblasts. In particular, blue light (450 nm) specifically down-regulated proliferation, metabolism and protein synthesis molecular pathways. At the protein level, 450-nm light inhibited the production of procollagen I in human reticular and papillary fibroblasts in a dose-dependent manner. Gene expression results were in agreement i.e., the same light parameter down-regulated collagen fiber genes, integrins and up-regulated collagenase MMP1. This thesis concludes with a chapter presenting a characterization of the accuracy of a potential translation tool for the prediction of optical photon density inside human skin."]},{"key":"dc:title","label":"Title","values":["Photo-biomodulation of human skin fibroblast sub-populations: a systematic approach for the optimization of optical treatment parameters"]}]}],"canonical_facts":{"dc:contributor.advisor":["Tobin, Desmond J.","Uzunbajakava, N.E.","Botchkareva, Natalia V.","Zeitouny, M."],"dc:creator":["Mignon, Charles"],"dc:date.accessioned":["2018-05-30T09:36:03Z"],"dc:date.available":["2018-05-30T09:36:03Z"],"dc:date.issued":["2017"],"dc:description.abstract":["The thesis presents a rational path for the optimization of the selection of optical treatment parameters in photobiomodulation of human skin fibroblasts. The project begins with an extensive analysis of 90 bibliographic reports in photobiomodulation published between 1985 and 2015, and revealed major inconsistencies in optical parameters selected for clinical applications. Seeking greater clarity for optimal parameter choice, a systematic approach to disentangle the multiple factors underpinning the response of human dermal fibroblasts in vitro to visible and near-infra red (NIR) light was employed. Light-based devices were constructed to specifically and systematically screen the optical parameter window (i.e. wavelength, irradiance and dose) observed in literature. Additionally, critical culture and treatment conditions that have dramatic impact on the outcome of specific light treatment of these human skin dermal cells were identified. In particular, environmental oxygen concentration, cell confluency and serum concentration were all found to have a great effect on the response of dermal fibroblasts to light. In parallel, the induction of reactive oxygen species (ROS) by short visible wavelengths on two dermal fibroblast sub-populations or lineage, reticular and papillary, was monitored by live-cell imaging. The ROS species were found to be created in or close to mitochondria. Lastly, gene expression studies revealed a strong impact of short visible wavelengths, as compared to long and NIR wavelengths on both subpopulations of human dermal fibroblasts. In particular, blue light (450 nm) specifically down-regulated proliferation, metabolism and protein synthesis molecular pathways. At the protein level, 450-nm light inhibited the production of procollagen I in human reticular and papillary fibroblasts in a dose-dependent manner. Gene expression results were in agreement i.e., the same light parameter down-regulated collagen fiber genes, integrins and up-regulated collagenase MMP1. This thesis concludes with a chapter presenting a characterization of the accuracy of a potential translation tool for the prediction of optical photon density inside human skin."],"dc:identifier.uri":["http://hdl.handle.net/10454/16064"],"dc:language.iso":["en"],"dc:publisher.department":["Centre for Skin Science, Faculty of Life Sciences"],"dc:publisher.institution":["University of Bradford"],"dc:rights":["\"Creative
The University of Bradford theses are licenced under a Creative Commons Licence."],"dc:subject":["Photobiomodulation","Skin","Light","Subpopulations","Design of experiment","Monte Carlo method","Human dermal fibroblasts (HDF)"],"dc:title":["Photo-biomodulation of human skin fibroblast sub-populations: a systematic approach for the optimization of optical treatment parameters"],"dc:type":["Thesis"],"dc:type.qualificationlevel":["doctoral"],"dc:type.qualificationname":["PhD"]},"updated_at":"2026-07-24T01:14:08Z"}