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Sharma M, Brown AW, Powell NM, Rajaram N, Tong L, Mourani PM, Schootman M. Racial and skin color mediated disparities in pulse oximetry in infants and young children. Paediatr Respir Rev 2024; 50:62-72. [PMID: 38233229 PMCID: PMC11139570 DOI: 10.1016/j.prrv.2023.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 01/19/2024]
Abstract
Race-based and skin pigmentation-related inaccuracies in pulse oximetry have recently been highlighted in several large electronic health record-based retrospective cohort studies across diverse patient populations and healthcare settings. Overestimation of oxygen saturation by pulse oximeters, particularly in hypoxic states, is disparately higher in Black compared to other racial groups. Compared to adult literature, pediatric studies are relatively few and mostly reliant on birth certificates or maternal race-based classification of comparison groups. Neonates, infants, and young children are particularly susceptible to the adverse life-long consequences of hypoxia and hyperoxia. Successful neonatal resuscitation, precise monitoring of preterm and term neonates with predominantly lung pathology, screening for congenital heart defects, and critical decisions on home oxygen, ventilator support and medication therapies, are only a few examples of situations that are highly reliant on the accuracy of pulse oximetry. Undetected hypoxia, especially if systematically different in certain racial groups may delay appropriate therapies and may further perpetuate health care disparities. The role of biological factors that may differ between racial groups, particularly skin pigmentation that may contribute to biased pulse oximeter readings needs further evaluation. Developmental and maturational changes in skin physiology and pigmentation, and its interaction with the operating principles of pulse oximetry need further study. Importantly, clinicians should recognize the limitations of pulse oximetry and use additional objective measures of oxygenation (like co-oximetry measured arterial oxygen saturation) where hypoxia is a concern.
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Affiliation(s)
- Megha Sharma
- Department of Pediatrics, Division of Neonatology, University of Arkansas for Medical Sciences, Little Rock, AR, United States; Arkansas Children's Research Institute, Little Rock, AR, United States.
| | - Andrew W Brown
- Department of Biostatistics, University of Arkansas for Medical Sciences, Little Rock, AR, United States; Arkansas Children's Research Institute, Little Rock, AR, United States
| | - Nicholas M Powell
- Department of Biomedical Engineering, University of Arkansas, Fayetteville, AR, United States
| | - Narasimhan Rajaram
- Department of Biomedical Engineering, University of Arkansas, Fayetteville, AR, United States; Winthrop P. Rockefeller Cancer Institute, Little Rock, AR, United States
| | - Lauren Tong
- Clinical Library Services, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Peter M Mourani
- Arkansas Children's Research Institute, Little Rock, AR, United States; Department of Pediatrics, Division of Pediatric Critical Care, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Mario Schootman
- Department of Internal Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, United States
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2
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Gao Y, Feng T, Qiu H, Gu Y, Chen Q, Zuo C, Ma H. 4D spectral-spatial computational photoacoustic dermoscopy. PHOTOACOUSTICS 2023; 34:100572. [PMID: 38058749 PMCID: PMC10696115 DOI: 10.1016/j.pacs.2023.100572] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 10/16/2023] [Accepted: 11/09/2023] [Indexed: 12/08/2023]
Abstract
Photoacoustic dermoscopy (PAD) is an emerging non-invasive imaging technology aids in the diagnosis of dermatological conditions by obtaining optical absorption information of skin tissues. Despite advances in PAD, it remains unclear how to obtain quantitative accuracy of the reconstructed PAD images according to the optical and acoustic properties of multilayered skin, the wavelength and distribution of excitation light, and the detection performance of ultrasound transducers. In this work, a computing method of four-dimensional (4D) spectral-spatial imaging for PAD is developed to enable quantitative analysis and optimization of structural and functional imaging of skin. This method takes the optical and acoustic properties of heterogeneous skin tissues into account, which can be used to correct the optical field of excitation light, detectable ultrasonic field, and provide accurate single-spectrum analysis or multi-spectral imaging solutions of PAD for multilayered skin tissues. A series of experiments were performed, and simulation datasets obtained from the computational model were used to train neural networks to further improve the imaging quality of the PAD system. All the results demonstrated the method could contribute to the development and optimization of clinical PADs by datasets with multiple variable parameters, and provide clinical predictability of photoacoustic (PA) data for human skin.
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Affiliation(s)
- Yang Gao
- Nanjing University of Science and Technology, School of Electronic and Optical Engineering, Smart Computational Imaging Laboratory (SCILab), Nanjing 210094, China
- Smart Computational Imaging Research Institute (SCIRI) of Nanjing University of Science and Technology, Nanjing 210094, China
- Nanjing University of Science and Technology, School of Electronic and Optical Engineering, Jiangsu Key Laboratory of Spectral Imaging & Intelligent Sense, Nanjing 210094, China
| | - Ting Feng
- Fudan University, Academy for Engineering and Technology, Shanghai 200433, China
| | - Haixia Qiu
- First Medical Center of PLA General Hospital, Beijing 100853, China
| | - Ying Gu
- First Medical Center of PLA General Hospital, Beijing 100853, China
| | - Qian Chen
- Nanjing University of Science and Technology, School of Electronic and Optical Engineering, Smart Computational Imaging Laboratory (SCILab), Nanjing 210094, China
- Nanjing University of Science and Technology, School of Electronic and Optical Engineering, Jiangsu Key Laboratory of Spectral Imaging & Intelligent Sense, Nanjing 210094, China
| | - Chao Zuo
- Nanjing University of Science and Technology, School of Electronic and Optical Engineering, Smart Computational Imaging Laboratory (SCILab), Nanjing 210094, China
- Smart Computational Imaging Research Institute (SCIRI) of Nanjing University of Science and Technology, Nanjing 210094, China
- Nanjing University of Science and Technology, School of Electronic and Optical Engineering, Jiangsu Key Laboratory of Spectral Imaging & Intelligent Sense, Nanjing 210094, China
| | - Haigang Ma
- Nanjing University of Science and Technology, School of Electronic and Optical Engineering, Smart Computational Imaging Laboratory (SCILab), Nanjing 210094, China
- Smart Computational Imaging Research Institute (SCIRI) of Nanjing University of Science and Technology, Nanjing 210094, China
- Nanjing University of Science and Technology, School of Electronic and Optical Engineering, Jiangsu Key Laboratory of Spectral Imaging & Intelligent Sense, Nanjing 210094, China
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3
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Jeon G, Choi H, Park DJ, Nguyen NT, Kim YH, Min J. Melanin Treatment Effect of Vacuoles-Zinc Oxide Nanoparticles Combined with Ascorbic Acid. Mol Biotechnol 2022:10.1007/s12033-022-00608-8. [PMID: 36445610 PMCID: PMC9707414 DOI: 10.1007/s12033-022-00608-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 11/07/2022] [Indexed: 11/30/2022]
Abstract
Currently, ascorbic acid (AA) is widely used as a skin whitening material, but, AA, an unstable hydrophilic molecule, cannot penetrate the skin easily, due to the hydrophobic character of the stratum corneum. Therefore, we conjugated AA with hydrated zinc oxide-an inorganic matrix with positive surface charge, to improve the stability of AA. The metal-conjugated-ascorbic acid (ZnAA) was then combined with yeast vacuole through the vacuolar membrane proteins that relate to metal transportation to create an enhanced vacuole that contained ZnAA. The characteristics of vacuole with ZnAA (ZnAA_Vac) were next examined by various tests that included X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Field emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray (EDX) analysis. Furthermore, the ability of ZnAA_Vac to degrade melanin was confirmed in both melanoma cell line B16F10, and the artificial human skin MelanoDerm. The results showed that ZnAA_Vac possessed a higher depigmenting effect than the wild-type vacuole or ascorbic acid by reducing 75% of melanin color. Interestingly, ZnAA_Vac was found to be harmless, and did not cause any cytotoxicity to the cells. Overall, ZnAA_Vac is expected to provide a robust, harmless, and effective whitening agent for the skin.
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Affiliation(s)
- Gyeongchan Jeon
- Graduate School of Semiconductor and Chemical Engineering, Jeonbuk National University, 567 Baekje-Daero, Deokjin-Gu, Jeonju-Si, Jeollabuk-do 54896 Republic of Korea
| | - Hyojin Choi
- Graduate School of Semiconductor and Chemical Engineering, Jeonbuk National University, 567 Baekje-Daero, Deokjin-Gu, Jeonju-Si, Jeollabuk-do 54896 Republic of Korea
| | - Dong-Jun Park
- Department of Surgery, University of California, San Diego, USA
| | - Ngoc-Tu Nguyen
- Center for Ecology and Environmental Toxicology (CEET), Chungbuk National University, 1 Chungdae-Ro, Seowon-Gu, Cheongju, Chungbuk-Do 28644 South Korea
| | - Yang-Hoon Kim
- Center for Ecology and Environmental Toxicology (CEET), Chungbuk National University, 1 Chungdae-Ro, Seowon-Gu, Cheongju, Chungbuk-Do 28644 South Korea
- School of Biological Science, Chungbuk National University, Chungdae-Ro 1, Seowon-Gu, Cheongju, Chungbuk-do 28644 Republic of Korea
| | - Jiho Min
- Graduate School of Semiconductor and Chemical Engineering, Jeonbuk National University, 567 Baekje-Daero, Deokjin-Gu, Jeonju-Si, Jeollabuk-do 54896 Republic of Korea
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Finlayson L, Barnard IRM, McMillan L, Ibbotson SH, Brown CTA, Eadie E, Wood K. Depth Penetration of Light into Skin as a Function of Wavelength from 200 to 1000 nm. Photochem Photobiol 2022; 98:974-981. [PMID: 34699624 DOI: 10.1111/php.13550] [Citation(s) in RCA: 74] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 10/23/2021] [Indexed: 12/13/2022]
Abstract
An increase in the use of light-based technology and medical devices has created a demand for informative and accessible data showing the depth that light penetrates into skin and how this varies with wavelength. These data would be particularly beneficial in many areas of medical research and would support the use and development of disease-targeted light-based therapies for specific skin diseases, based on increased understanding of wavelength-dependency of cutaneous penetration effects. We have used Monte Carlo radiative transport (MCRT) to simulate light propagation through a multi-layered skin model for the wavelength range of 200-1000 nm. We further adapted the simulation to compare the effect of direct and diffuse light sources, varying incident angles and stratum corneum thickness. The lateral spread of light in skin was also investigated. As anticipated, we found that the penetration depth of light into skin varies with wavelength in accordance with the optical properties of skin. Penetration depth of ultraviolet radiation was also increased when the stratum corneum was thinner. These observations enhance understanding of the wavelength-dependency and characteristics of light penetration of skin, which has potential for clinical impact regarding optimizing light-based diagnostic and therapeutic approaches for skin disease.
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Affiliation(s)
- Louise Finlayson
- SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, UK
| | - Isla R M Barnard
- SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, UK
| | - Lewis McMillan
- SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, UK
| | - Sally H Ibbotson
- Photobiology Unit, Ninewells Hospital, University of Dundee, Dundee, UK
| | - C Tom A Brown
- SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, UK
| | - Ewan Eadie
- Photobiology Unit, Ninewells Hospital, NHS Tayside, Dundee, UK
| | - Kenneth Wood
- SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, UK
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5
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Kallepalli A, Halls J, James DB, Richardson MA. An ultrasonography-based approach for tissue modelling to inform photo-therapy treatment strategies. JOURNAL OF BIOPHOTONICS 2022; 15:e202100275. [PMID: 35044094 DOI: 10.1002/jbio.202100275] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 01/11/2022] [Accepted: 01/12/2022] [Indexed: 06/14/2023]
Abstract
Currently, diagnostic medicine uses a multitude of tools ranging from ionising radiation to histology analysis. With advances in piezoelectric crystal technology, high-frequency ultrasound imaging has developed to achieve comparatively high resolution without the drawbacks of ionising radiation. This research proposes a low-cost, non-invasive and real-time protocol for informing photo-therapy procedures using ultrasound imaging. We combine currently available ultrasound procedures with Monte Carlo methods for assessing light transport and photo-energy deposition in the tissue. The measurements from high-resolution ultrasound scans are used as input for optical simulations. Consequently, this provides a pipeline that will inform medical practitioners for better therapy strategy planning. While validating known inferences of light transport through biological tissue, our results highlight the range of information such as temporal monitoring and energy deposition at varying depths. This process also retains the flexibility of testing various wavelengths for individual-specific geometries and anatomy.
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Affiliation(s)
- Akhil Kallepalli
- School of Physics and Astronomy, University of Glasgow, Glasgow, UK
| | - James Halls
- Department of Radiology, The Great Western Hospital, Swindon, UK
| | - David B James
- Centre for Electronic Warfare, Information and Cyber, Cranfield University, Defence Academy of the UK, Shrivenham, UK
| | - Mark A Richardson
- Centre for Electronic Warfare, Information and Cyber, Cranfield University, Defence Academy of the UK, Shrivenham, UK
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6
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Main M, J J Pilkington R, Gibson GM, Kallepalli A. Simulated assessment of light transport through ischaemic skin flaps. Br J Oral Maxillofac Surg 2022; 60:969-973. [DOI: 10.1016/j.bjoms.2022.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 02/25/2022] [Accepted: 03/15/2022] [Indexed: 10/18/2022]
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7
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Zywot EM, Orlova N, Ding S, Rampersad RR, Rabjohns EM, Wickenheisser VA, Wang Q, Welfare JG, Haar L, Eudy AM, Tarrant TK, Lawrence DS. Light-Triggered Drug Release from Red Blood Cells Suppresses Arthritic Inflammation. ADVANCED THERAPEUTICS 2022; 5:2100159. [PMID: 35528736 PMCID: PMC9075171 DOI: 10.1002/adtp.202100159] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Indexed: 01/03/2023]
Abstract
Arthritis is a leading cause of disability in adults, which can be intensely incapacitating. The location and intensity of the pain is both subjective and challenging to manage. Consequently, patient-directed delivery of anti-inflammatories is an essential component of future therapeutic strategies for the management of this disorder. We describe the design and application of a light responsive red blood cell (RBC) conveyed dexamethasone (Dex) construct that enables targeted drug delivery upon illumination of the inflamed site. The red wavelength (650 nm) responsive nature of the phototherapeutic was validated using tissue phantoms mimicking the light absorbing properties of various skin types. Furthermore, photoreleased Dex has the same impact on cellular responses as conventional Dex. Murine RBCs containing the photoactivatable therapeutic display comparable circulation properties as fluorescently labelled RBCs. In addition, a single dose of light-targeted Dex delivery is 5-fold more effective in suppressing inflammation than the parent drug, delivered serially over multiple days. These results are consistent with the notion that the circulatory system be used as an on-command drug depot, providing the means to therapeutically target diseased sites both efficiently and effectively.
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Affiliation(s)
- Emilia M Zywot
- Division of Chemical Biology and Medicinal Chemistry, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Natalia Orlova
- Division of Chemical Biology and Medicinal Chemistry, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Song Ding
- Division of Chemical Biology and Medicinal Chemistry, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Rishi R Rampersad
- Department of Medicine, Division of Rheumatology and Immunology, Duke University, Durham, NC 27710, USA
| | - Emily M Rabjohns
- Department of Medicine, Division of Rheumatology and Immunology, Duke University, Durham, NC 27710, USA
| | - Victoria A Wickenheisser
- Department of Medicine, Division of Rheumatology and Immunology, Duke University, Durham, NC 27710, USA
| | - Qunzhao Wang
- Division of Chemical Biology and Medicinal Chemistry, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Joshua G Welfare
- Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Lauren Haar
- Division of Chemical Biology and Medicinal Chemistry, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Amanda M Eudy
- Department of Medicine, Division of Rheumatology and Immunology, Duke University, Durham, NC 27710, USA
| | - Teresa K Tarrant
- Department of Medicine, Division of Rheumatology and Immunology, Duke University, Durham, NC 27710, USA
| | - David S Lawrence
- Division of Chemical Biology and Medicinal Chemistry, University of North Carolina, Chapel Hill, NC 27599, USA
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8
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Datta P, Philipsen PA, Idorn LW, Wulf HC. Low vitamin D in dark-skinned immigrants is mainly due to clothing habits and low UVR exposure: a Danish observational study. Photochem Photobiol Sci 2021; 20:1573-1584. [PMID: 34718967 DOI: 10.1007/s43630-021-00115-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Accepted: 10/11/2021] [Indexed: 10/19/2022]
Abstract
Low 25-hydroxyvitamin D3 (25(OH)D) among dark-pigmented persons has been observed. To elucidate the reason for this we examined sun behaviour, sun-exposed body area, solar UVR exposure and 25(OH)D levels in immigrants with dark pigmented skin and Danes with light pigmented skin. Clothing, sun behaviour, and diet were recorded daily during a Danish summer season (93 analysed days). Erythema-weighted UVR doses were measured by personal electronic UVR dosimeters (with erythema response, measurement every 5th second) and 25(OH)D was measured in 72 participants (33 dark-skinned and 39 light-skinned). The immigrants exposed 28% less skin area, received 70% less UVR dose, and had 71% less 25(OH)D increase during the summer. The UVR reactivity (Δ25(OH)D per joule accumulated UVR dose) was similar (P = 0.62) among the immigrants (0.53 nmol l-1 J-1) and the Danes (0.63 nmol l-1 J-1). In the groups combined, 25(OH)D levels after summer were mainly influenced by UVR dose to exposed skin (28.8%) and 25(OH)D start level (27.9%). Height and measured constitutive skin pigmentation were of minor influence: 3.5% and 3.2%, respectively. Sun exposure and clothing habits were the main reasons for lower 25(OH)D level after summer in the darker immigrants, as both groups had similar UVR reactivity.
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Affiliation(s)
- Pameli Datta
- Department of Dermatology D92, Bispebjerg Hospital, University of Copenhagen, Nielsine Nielsens Vej 17, 2400, Copenhagen NV, Denmark.
| | - Peter Alshede Philipsen
- Department of Dermatology D92, Bispebjerg Hospital, University of Copenhagen, Nielsine Nielsens Vej 17, 2400, Copenhagen NV, Denmark
| | - Luise Winkel Idorn
- Department of Dermatology D92, Bispebjerg Hospital, University of Copenhagen, Nielsine Nielsens Vej 17, 2400, Copenhagen NV, Denmark
| | - Hans Christian Wulf
- Department of Dermatology D92, Bispebjerg Hospital, University of Copenhagen, Nielsine Nielsens Vej 17, 2400, Copenhagen NV, Denmark
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9
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Proposal for a Skin Layer-Wise Decomposition Model of Spatially-Resolved Diffuse Reflectance Spectra Based on Maximum Depth Photon Distributions: A Numerical Study. PHOTONICS 2021. [DOI: 10.3390/photonics8100444] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In the context of cutaneous carcinoma diagnosis based on in vivo optical biopsy, Diffuse Reflectance (DR) spectra, acquired using a Spatially Resolved (SR) sensor configuration, can be analyzed to distinguish healthy from pathological tissues. The present contribution aims at studying the depth distribution of SR-DR-detected photons in skin from the perspective of analyzing how these photons contribute to acquired spectra carrying local physiological and morphological information. Simulations based on modified Cuda Monte Carlo Modeling of Light transport were performed on a five-layer human skin optical model with epidermal thickness, phototype and dermal blood content as variable parameters using (i) wavelength-resolved scattering and absorption properties and (ii) the geometrical configuration of a multi-optical fiber probe implemented on an SR-DR spectroscopic device currently used in clinics. Through histograms of the maximum probed depth and their exploitation, we provide numerical evidence linking the characteristic penetration depth of the detected photons to their wavelengths and four source–sensor distances, which made it possible to propose a decomposition of the DR signals related to skin layer contributions.
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10
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Galeb HA, Wilkinson EL, Stowell AF, Lin H, Murphy ST, Martin‐Hirsch PL, Mort RL, Taylor AM, Hardy JG. Melanins as Sustainable Resources for Advanced Biotechnological Applications. GLOBAL CHALLENGES (HOBOKEN, NJ) 2021; 5:2000102. [PMID: 33552556 PMCID: PMC7857133 DOI: 10.1002/gch2.202000102] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/04/2020] [Indexed: 05/17/2023]
Abstract
Melanins are a class of biopolymers that are widespread in nature and have diverse origins, chemical compositions, and functions. Their chemical, electrical, optical, and paramagnetic properties offer opportunities for applications in materials science, particularly for medical and technical uses. This review focuses on the application of analytical techniques to study melanins in multidisciplinary contexts with a view to their use as sustainable resources for advanced biotechnological applications, and how these may facilitate the achievement of the United Nations Sustainable Development Goals.
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Affiliation(s)
- Hanaa A. Galeb
- Department of ChemistryLancaster UniversityLancasterLA1 4YBUK
- Department of ChemistryScience and Arts CollegeRabigh CampusKing Abdulaziz UniversityJeddah21577Saudi Arabia
| | - Emma L. Wilkinson
- Department of Biomedical and Life SciencesLancaster UniversityLancasterLA1 4YGUK
| | - Alison F. Stowell
- Department of Organisation, Work and TechnologyLancaster University Management SchoolLancaster UniversityLancasterLA1 4YXUK
| | - Hungyen Lin
- Department of EngineeringLancaster UniversityLancasterLA1 4YWUK
| | - Samuel T. Murphy
- Department of EngineeringLancaster UniversityLancasterLA1 4YWUK
- Materials Science InstituteLancaster UniversityLancasterLA1 4YBUK
| | - Pierre L. Martin‐Hirsch
- Lancashire Teaching Hospitals NHS TrustRoyal Preston HospitalSharoe Green LanePrestonPR2 9HTUK
| | - Richard L. Mort
- Department of Biomedical and Life SciencesLancaster UniversityLancasterLA1 4YGUK
| | - Adam M. Taylor
- Lancaster Medical SchoolLancaster UniversityLancasterLA1 4YWUK
| | - John G. Hardy
- Department of ChemistryLancaster UniversityLancasterLA1 4YBUK
- Materials Science InstituteLancaster UniversityLancasterLA1 4YBUK
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11
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Truong VX, Barner-Kowollik C. Red-Light Driven Photocatalytic Oxime Ligation for Bioorthogonal Hydrogel Design. ACS Macro Lett 2021; 10:78-83. [PMID: 35548995 DOI: 10.1021/acsmacrolett.0c00767] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Light-mediated polymer cross-linking is frequently employed for the preparation of hydrogels for biomedical applications. However, most photopolymerization processes require activation by UV light or short wavelength visible light, which are highly absorbed by skin and tissue, limiting their uses in transdermal initiation. Herein, we introduce red light-enabled oxime ligation by the in situ photogeneration of aldehydes, which rapidly react with hydroxylamines. We demonstrate efficient polymer cross-linking behind a dermal tissue model by red light initiation. Optimization of the photopolymerization conditions allows for 3D encapsulation of human foreskin fibroblasts with good cell viability postencapsulation.
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Affiliation(s)
- Vinh X. Truong
- School of Chemistry and Physics, Queensland University of Technology, Brisbane, Queensland 4000, Australia
- Centre for Materials Science, School of Chemistry and Physics, Queensland University of Technology (QUT), Brisbane 4000, Australia
| | - Christopher Barner-Kowollik
- School of Chemistry and Physics, Queensland University of Technology, Brisbane, Queensland 4000, Australia
- Centre for Materials Science, School of Chemistry and Physics, Queensland University of Technology (QUT), Brisbane 4000, Australia
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12
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Huang X, Protheroe MD, Al-Jumaily AM, Paul SP, Chalmers AN. Effect of hair removal on solar UV transmission into skin and implications for melanoma skin cancer development. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2020; 37:807-812. [PMID: 32400714 DOI: 10.1364/josaa.387558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 04/01/2020] [Indexed: 06/11/2023]
Abstract
Melanoma is the severest type of skin cancer. As distinct from many other cancer types, the incidence of melanoma has been increasing steadily over the last century. Discovering new risk factors of melanoma will not only raise public awareness but also potentially contribute to the improvement of skin cancer protection in the future. Nowadays, the tendency of shaving skin hair is becoming increasingly popular for aesthetic purposes. However, human hair serves several functions, one of which is ultraviolet (UV) protection for the skin. What is more, stem cells found in the follicles of hair could be the origin of melanoma upon exposure to ultraviolet radiation. Therefore, it is of interest to investigate the effect of shaving on solar UV transmission in the skin. To achieve that, two groups of skin models are constructed in TracePro software: one with unaltered hair and one with shaved hair. The UV transport in the models is simulated using the Monte Carlo method and the absorptions in the stem cells layer are compared. It is found that shaving will increase the UV transmission to the follicular stem cells to a certain degree. More specifically, shaving limbs will generally increase the solar UV transmission from about 5% to 20% in the UV wavelength range.
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13
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Kanellis VG. A review of melanin sensor devices. Biophys Rev 2019; 11:843-849. [PMID: 31396804 PMCID: PMC6874939 DOI: 10.1007/s12551-019-00581-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Accepted: 07/31/2019] [Indexed: 02/01/2023] Open
Abstract
Knowing how readily the skin produces melanin is invaluable in reducing photochemical and phototherapy overtreatment in dermatology and also in reducing the risk of actinic skin damage and skin cancer from excessive radiant light exposure. The commonly used Fitzpatrick skin type (FST) classification scale is often used to subjectively assess ultraviolet light sensitivity and susceptibility to sunburn following significant sunlight exposure. However, the FST scale falls short in the assessment of nonwhite skin types. Alternatively, commercially available melanin sensor devices, called melanometers, can be used to objectively quantify useful skin parameters such as the epidermal melanin concentration (EMC). This study reviews commercially available melanometers and their use in quantifying epidermal melanin concentration (EMC) and the individual maximum safe radiant exposure (IMSRE) for an individual in clinical, workplace and community settings.
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14
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Abdulhameed YA, Lancaster G, McClintock PVE, Stefanovska A. On the suitability of laser-Doppler flowmetry for capturing microvascular blood flow dynamics from darkly pigmented skin. Physiol Meas 2019; 40:074005. [DOI: 10.1088/1361-6579/ab2651] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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15
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Wollweber M, Roth B. Raman Sensing and Its Multimodal Combination with Optoacoustics and OCT for Applications in the Life Sciences. SENSORS (BASEL, SWITZERLAND) 2019; 19:E2387. [PMID: 31137716 PMCID: PMC6566696 DOI: 10.3390/s19102387] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 05/10/2019] [Accepted: 05/15/2019] [Indexed: 12/29/2022]
Abstract
Currently, many optical modalities are being investigated, applied, and further developed for non-invasive analysis and sensing in the life sciences. To befit the complexity of the study objects and questions in this field, the combination of two or more modalities is attempted. We review our work on multimodal sensing concepts for applications ranging from non-invasive quantification of biomolecules in the living organism to supporting medical diagnosis showing the combined capabilities of Raman spectroscopy, optical coherence tomography, and optoacoustics.
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Affiliation(s)
- Merve Wollweber
- Laser Zentrum Hannover e.V., Industrial and Biomedical Optics Department, Hollerithallee 8, 30419 Hannover, Germany.
- Hannover Centre for Optical Technologies, Leibniz University Hannover, Nienburger Str. 17, 30167 Hannover, Germany.
| | - Bernhard Roth
- Hannover Centre for Optical Technologies, Leibniz University Hannover, Nienburger Str. 17, 30167 Hannover, Germany.
- Cluster of Excellence PhoenixD, Leibniz University Hannover, Welfengarten 1, 30167 Hannover, Germany.
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16
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Barnard IRM, Tierney P, Campbell CL, McMillan L, Moseley H, Eadie E, Brown CTA, Wood K. Quantifying Direct DNA Damage in the Basal Layer of Skin Exposed to UV Radiation from Sunbeds. Photochem Photobiol 2018; 94:1017-1025. [PMID: 29752876 DOI: 10.1111/php.12935] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 04/12/2018] [Indexed: 12/22/2022]
Abstract
Nonmelanoma and melanoma skin cancers are attributable to DNA damage caused by ultraviolet (UV) radiation exposure. One DNA photoproduct, the cyclobutane pyrimidine dimer (CPD), is believed to lead to DNA mutations caused by UV radiation. Using radiative transfer simulations, we compare the number of CPDs directly induced by UV irradiation from artificial and natural UV sources (a standard sunbed and the midday summer Mediterranean sun) for skin types I and II on the Fitzpatrick scale. We use Monte Carlo radiative transfer (MCRT) modeling to track the progression of UV photons through a multilayered three dimensional (3D) grid that simulates the upper layers of the skin. By recording the energy deposited in the DNA-containing cells of the basal layer, the number of CPDs formed can be quantified. The aim of this work was to compare the number of CPDs formed in the basal layer of the skin and by implication the risk of developing cancer, as a consequence of irradiation by artificial and natural sources. Our simulations show that the number of CPDs formed per second during sunbed irradiation is almost three times that formed during solar irradiation.
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Affiliation(s)
| | - Patrick Tierney
- Photobiology Unit, Ninewells Hospital & Medical School, University of Dundee, Dundee, UK
| | | | - Lewis McMillan
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK
| | - Harry Moseley
- Photobiology Unit, Ninewells Hospital & Medical School, University of Dundee, Dundee, UK
| | - Ewan Eadie
- Photobiology Unit, Ninewells Hospital & Medical School, NHS Tayside, Dundee, UK
| | | | - Kenneth Wood
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK
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Mignon C, Tobin DJ, Zeitouny M, Uzunbajakava NE. Shedding light on the variability of optical skin properties: finding a path towards more accurate prediction of light propagation in human cutaneous compartments. BIOMEDICAL OPTICS EXPRESS 2018; 9:852-872. [PMID: 29552418 PMCID: PMC5854084 DOI: 10.1364/boe.9.000852] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 12/14/2017] [Accepted: 12/30/2017] [Indexed: 05/04/2023]
Abstract
Finding a path towards a more accurate prediction of light propagation in human skin remains an aspiration of biomedical scientists working on cutaneous applications both for diagnostic and therapeutic reasons. The objective of this study was to investigate variability of the optical properties of human skin compartments reported in literature, to explore the underlying rational of this variability and to propose a dataset of values, to better represent an in vivo case and recommend a solution towards a more accurate prediction of light propagation through cutaneous compartments. To achieve this, we undertook a novel, logical yet simple approach. We first reviewed scientific articles published between 1981 and 2013 that reported on skin optical properties, to reveal the spread in the reported quantitative values. We found variations of up to 100-fold. Then we extracted the most trust-worthy datasets guided by a rule that the spectral properties should reflect the specific biochemical composition of each of the skin layers. This resulted in the narrowing of the spread in the calculated photon densities to 6-fold. We conclude with a recommendation to use the identified most robust datasets when estimating light propagation in human skin using Monte Carlo simulations. Alternatively, otherwise follow our proposed strategy to screen any new datasets to determine their biological relevance.
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Affiliation(s)
- C. Mignon
- Centre for Skin Sciences, Faculty of Life Sciences, University of Bradford, Richmond Road, BD7 1DP, Bradford, West Yorkshire,
UK
| | - D. J. Tobin
- Centre for Skin Sciences, Faculty of Life Sciences, University of Bradford, Richmond Road, BD7 1DP, Bradford, West Yorkshire,
UK
| | - M. Zeitouny
- Philips Research, High Tech Campus 11, 5656 AE Eindhoven,
The Netherlands
| | - N. E. Uzunbajakava
- Philips Research, High Tech Campus 11, 5656 AE Eindhoven,
The Netherlands
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18
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Piazena H, Meffert H, Uebelhack R. Spectral Remittance and Transmittance of Visible and Infrared-A Radiation in Human Skin-Comparison Betweenin vivoMeasurements and Model Calculations. Photochem Photobiol 2017; 93:1449-1461. [DOI: 10.1111/php.12785] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 04/04/2017] [Indexed: 11/26/2022]
Affiliation(s)
- Helmut Piazena
- Medical Photobiology Group; Charité - University Medicine Berlin; Berlin Germany
| | | | - Ralf Uebelhack
- Medical Photobiology Group; Charité - University Medicine Berlin; Berlin Germany
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Blumenröther E, Melchert O, Wollweber M, Roth B. Detection, numerical simulation and approximate inversion of optoacoustic signals generated in multi-layered PVA hydrogel based tissue phantoms. PHOTOACOUSTICS 2016; 4:125-132. [PMID: 27833857 PMCID: PMC5096600 DOI: 10.1016/j.pacs.2016.10.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 09/15/2016] [Accepted: 10/19/2016] [Indexed: 05/15/2023]
Abstract
Optoacoustic (OA) measurements can not only be used for imaging purposes but as a more general tool to "sense" physical characteristics of biological tissue, such as geometric features and intrinsic optical properties. In order to pave the way for a systematic model-guided analysis of complex objects we devised numerical simulations in accordance with the experimental measurements. We validate our computational approach with experimental results observed for layered polyvinyl alcohol hydrogel samples, using melanin as the absorbing agent. Experimentally, we characterize the acoustic signal observed by a piezoelectric detector in the acoustic far-field in backward mode and we discuss the implication of acoustic diffraction on our measurements. We further attempt an inversion of an OA signal in the far-field approximation.
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Affiliation(s)
- E. Blumenröther
- Hannover Centre for Optical Technologies (HOT), Interdisciplinary Research Centre of the Leibniz Universität Hannover, Nienburger Str. 17, D-30167 Hannover, Germany
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20
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Greening GJ, Rajaram N, Muldoon TJ. Multimodal Imaging and Spectroscopy Fiber-bundle Microendoscopy Platform for Non-invasive, In Vivo Tissue Analysis. J Vis Exp 2016. [PMID: 27805585 DOI: 10.3791/54564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Recent fiber-bundle microendoscopy techniques enable non-invasive analysis of in vivo tissue using either imaging techniques or a combination of spectroscopy techniques. Combining imaging and spectroscopy techniques into a single optical probe may provide a more complete analysis of tissue health. In this article, two dissimilar modalities are combined, high-resolution fluorescence microendoscopy imaging and diffuse reflectance spectroscopy, into a single optical probe. High-resolution fluorescence microendoscopy imaging is a technique used to visualize apical tissue micro-architecture and, although mostly a qualitative technique, has demonstrated effective real-time differentiation between neoplastic and non-neoplastic tissue. Diffuse reflectance spectroscopy is a technique which can extract tissue physiological parameters including local hemoglobin concentration, melanin concentration, and oxygen saturation. This article describes the specifications required to construct the fiber-optic probe, how to build the instrumentation, and then demonstrates the technique on in vivo human skin. This work revealed that tissue micro-architecture, specifically apical skin keratinocytes, can be co-registered with its associated physiological parameters. The instrumentation and fiber-bundle probe presented here can be optimized as either a handheld or endoscopically-compatible device for use in a variety of organ systems. Additional clinical research is needed to test the viability of this technique for different epithelial disease states.
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Affiliation(s)
- Gage J Greening
- Department of Biomedical Engineering, University of Arkansas;
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21
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Fajuyigbe D, Young AR. The impact of skin colour on human photobiological responses. Pigment Cell Melanoma Res 2016; 29:607-618. [PMID: 27454804 PMCID: PMC5132026 DOI: 10.1111/pcmr.12511] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 07/11/2016] [Indexed: 01/30/2023]
Abstract
Terrestrial solar ultraviolet radiation (UVR) exerts both beneficial and adverse effects on human skin. Epidemiological studies show a lower incidence of skin cancer in people with pigmented skins compared to fair skins. This is attributed to photoprotection by epidermal melanin, as is the poorer vitamin D status of those with darker skins. We summarize a wide range of photobiological responses across different skin colours including DNA damage and immunosuppression. Some studies show the generally modest photoprotective properties of melanin, but others show little or no effect. DNA photodamage initiates non‐melanoma skin cancer and is reduced by a factor of about 3 in pigmented skin compared with white skin. This suggests that if such a modest reduction in DNA damage can result in the significantly lower skin cancer incidence in black skin, the use of sunscreen protection might be extremely beneficial for susceptible population. Many contradictory results may be explained by protocol differences, including differences in UVR spectra and exposure protocols. We recommend that skin type comparisons be done with solar‐simulated radiation and standard erythema doses or physical doses (J/m2) rather than those based solely on clinical endpoints such as minimal erythema dose (MED).
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Affiliation(s)
- Damilola Fajuyigbe
- Division of Genetics and Molecular Medicine, Faculty of Life Sciences and Medicine, St John's Institute of Dermatology, King's College London, London, UK
| | - Antony R Young
- Division of Genetics and Molecular Medicine, Faculty of Life Sciences and Medicine, St John's Institute of Dermatology, King's College London, London, UK
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Transmittance and Autofluorescence of Neonatal Rat Stratum Corneum: Nerolidol Increases the Dynamics and Partitioning of Protoporphyrin IX into Intercellular Membranes. J Fluoresc 2016; 26:709-17. [DOI: 10.1007/s10895-015-1758-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 12/28/2015] [Indexed: 10/22/2022]
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23
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Rodgers ZL, Hughes RM, Doherty LM, Shell JR, Molesky BP, Brugh AM, Forbes MDE, Moran AM, Lawrence DS. B(12)-mediated, long wavelength photopolymerization of hydrogels. J Am Chem Soc 2015; 137:3372-8. [PMID: 25697508 DOI: 10.1021/jacs.5b00182] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Medical hydrogel applications have expanded rapidly over the past decade. Implantation in patients by noninvasive injection is preferred, but this requires hydrogel solidification from a low viscosity solution to occur in vivo via an applied stimuli. Transdermal photo-cross-linking of acrylated biopolymers with photoinitiators and lights offers a mild, spatiotemporally controlled solidification trigger. However, the current short wavelength initiators limit curing depth and efficacy because they do not absorb within the optical window of tissue (600-900 nm). As a solution to the current wavelength limitations, we report the development of a red light responsive initiator capable of polymerizing a range of acrylated monomers. Photoactivation occurs within a range of skin type models containing high biochromophore concentrations.
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Affiliation(s)
- Zachary L Rodgers
- Department of Chemistry, ‡Division of Chemical Biology and Medicinal Chemistry, and § Department of Pharmacology, University of North Carolina , Chapel Hill, North Carolina 27599, United States
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24
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Hani AFM, Baba R, Shamsuddin N, Nugroho H. Determination of melanin types and relative concentrations: an observational study using a non-invasive inverse skin reflectance analysis. Int J Cosmet Sci 2014; 36:451-8. [PMID: 24925684 DOI: 10.1111/ics.12147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 06/05/2014] [Indexed: 10/25/2022]
Abstract
OBJECTIVE Melanin is a major skin colour pigment that is made up of eumelanin (the dark brown-black colour) and pheomelanin (the light red-yellow colour) pigments. Skin-whitening products typically contain depigmentation agents that reduce the level of pigmentation by changing the pheomelanin-eumelanin production. Similarly, in skin pigment treatment of skin disorders, the melanin production is managed accordingly. To assess and improve treatment efficacy, it is important to have a measurement tool that is capable of determining the melanin types objectively. So far, the efficacy assessment is subjective. In this study, an inverse skin reflectance pigmentation analysis system that determines eumelanin and pheomelanin content is developed and evaluated in an observational study involving 36 participants with skin photo type IV. METHODS The reflectance spectra of the left forearms of participants were analysed by the pigmentation analysis system to determine their skin parameters--pheomelanin and eumelanin concentrations, melanosome volume fraction, and epidermal thickness. The determined skin parameters are then inputted into the realistic skin model (RSM) of the Advanced Systems Analyses Program (asap®) to generate the ground truth reflectance spectra for the given skin parameters to validate the system. RESULTS The developed pigmentation analysis system is found to be accurate with a spectral error of 0.0163 ± 0.009 between measured reflectance and the reflectance output of the analysis system and RSM. The regression analysis shows a strong linear relationship (R(2) = 0.994) indicating good precision. The relative concentrations of pheomelanin (38.23 ± 15.04) and eumelanin (1.68 ± 0.91) analysed by the system gives a ratio of pheomelanin to eumelanin of 0.048 ± 0.029; this value is consistent with previously reported figure of 0.049. CONCLUSION The proposed pigmentation analysis system is able to determine melanin types and their relative concentrations. It has the potential to assess the efficacy of the skin-whitening and pigmentation treatments objectively in a non-invasive manner.
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Affiliation(s)
- A F M Hani
- Centre for Intelligent Signal and Imaging Research, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750, Tronoh, Perak Darul Ridzuan, Malaysia
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Sorg O, Saurat JH. Topical retinoids in skin ageing: a focused update with reference to sun-induced epidermal vitamin A deficiency. Dermatology 2014; 228:314-25. [PMID: 24821234 DOI: 10.1159/000360527] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 02/09/2014] [Indexed: 11/19/2022] Open
Abstract
Vitamin A is an important constituent of the epidermis, where it plays a crucial role in epidermal turnover. A deficiency of epidermal vitamin A may be the consequence of nutritional vitamin A deficiency, exposure to sunlight or any UV source, oxidative stress or chronological ageing. As a consequence, any treatment aiming at increasing epidermal vitamin A would exert a protective effect against these deleterious conditions. Retinoids may counteract some deleterious actions of UV radiation by physical and biological mechanisms. Topical natural retinoic acid precursors such as retinaldehyde or retinol are less irritant than acidic retinoids and may prevent epidermal vitamin A deficiency due to nutritional deficiency, exposure to sunlight or any condition leading to free radical production. Retinoids may be combined with other compounds with complementary actions against ageing, nutritional deficiency and cancer, such as antioxidants, to potentiate their beneficial effects in the skin.
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Affiliation(s)
- Olivier Sorg
- Swiss Centre for Applied Human Toxicology (SCAHT), University of Geneva, Geneva, Switzerland
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