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Oftadeh R, Azadi M, Donovan M, Langer J, Liao IC, Ortiz C, Grodzinsky AJ, Luengo GS. Poroelastic behavior and water permeability of human skin at the nanoscale. PNAS NEXUS 2023; 2:pgad240. [PMID: 37614672 PMCID: PMC10443659 DOI: 10.1093/pnasnexus/pgad240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 07/11/2023] [Accepted: 07/17/2023] [Indexed: 08/25/2023]
Abstract
Topical skin care products and hydrating compositions (moisturizers or injectable fillers) have been used for years to improve the appearance of, for example facial wrinkles, or to increase "plumpness". Most of the studies have addressed these changes based on the overall mechanical changes associated with an increase in hydration state. However, little is known about the water mobility contribution to these changes as well as the consequences to the specific skin layers. This is important as the biophysical properties and the biochemical composition of normal stratum corneum, epithelium, and dermis vary tremendously from one another. Our current studies and results reported here have focused on a novel approach (dynamic atomic force microscopy-based nanoindentation) to quantify biophysical characteristics of individual layers of ex vivo human skin. We have discovered that our new methods are highly sensitive to the mechanical properties of individual skin layers, as well as their hydration properties. Furthermore, our methods can assess the ability of these individual layers to respond to both compressive and shear deformations. In addition, since human skin is mechanically loaded over a wide range of deformation rates (frequencies), we studied the biophysical properties of skin over a wide frequency range. The poroelasticity model used helps to quantify the hydraulic permeability of the skin layers, providing an innovative method to evaluate and interpret the impact of hydrating compositions on water mobility of these different skin layers.
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Affiliation(s)
- Ramin Oftadeh
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Mojtaba Azadi
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- School of Engineering, San Francisco State University, San Francisco, CA 94132, USA
| | - Mark Donovan
- L’OREAL Research and Innovation, Aulnay sous Bois, 93106, France
| | | | - I-Chien Liao
- L'OREAL Research and Innovation, Clark, NJ 07066, USA
| | - Christine Ortiz
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Alan J Grodzinsky
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Gustavo S Luengo
- L’OREAL Research and Innovation, Aulnay sous Bois, 93106, France
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2
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Measurement of human skin moisture via high-frequency spectroscopy. ANAL SCI 2023; 39:851-856. [PMID: 36807897 DOI: 10.1007/s44211-023-00285-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 02/01/2023] [Indexed: 02/21/2023]
Abstract
High-frequency spectroscopy (HFS) is an analytical method that is sensitive to slight changes in the dielectric properties of materials. Since water has high permittivity, HFS can be used to detect changes in water content in materials. In this study, we employed HFS to measure human skin moisture during a water sorption-desorption test. Skin without any treatment showed a resonance peak at approximately 1150 MHz. Furthermore, the peak shifted to lower frequency immediately after the application of water to the skin and gradually returned to its original frequency as time progressed. The resonance frequency obtained via least-squares fitting showed that the applied water remained in the skin after 240 s from the beginning of the measurement. These results illustrated that HFS measurements can monitor the progression of decreasing moisture content in human skin during a water sorption-desorption test.
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Patel N, Clarke JF, Salem F, Abdulla T, Martins F, Arora S, Tsakalozou E, Hodgkinson A, Arjmandi-Tash O, Cristea S, Ghosh P, Alam K, Raney SG, Jamei M, Polak S. Multi-phase multi-layer mechanistic dermal absorption (MPML MechDermA) model to predict local and systemic exposure of drug products applied on skin. CPT Pharmacometrics Syst Pharmacol 2022; 11:1060-1084. [PMID: 35670226 PMCID: PMC9381913 DOI: 10.1002/psp4.12814] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 03/15/2022] [Accepted: 04/26/2022] [Indexed: 01/31/2023] Open
Abstract
Physiologically-based pharmacokinetic models combine knowledge about physiology, drug product properties, such as physicochemical parameters, absorption, distribution, metabolism, excretion characteristics, formulation attributes, and trial design or dosing regimen to mechanistically simulate drug pharmacokinetics (PK). The current work describes the development of a multiphase, multilayer mechanistic dermal absorption (MPML MechDermA) model within the Simcyp Simulator capable of simulating uptake and permeation of drugs through human skin following application of drug products to the skin. The model was designed to account for formulation characteristics as well as body site- and sex- population variability to predict local and systemic bioavailability. The present report outlines the structure and assumptions of the MPML MechDermA model and includes results from simulations comparing absorption at multiple body sites for two compounds, caffeine and benzoic acid, formulated as solutions. Finally, a model of the Feldene (piroxicam) topical gel, 0.5% was developed and assessed for its ability to predict both plasma and local skin concentrations when compared to in vivo PK data.
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Affiliation(s)
| | | | | | | | | | | | - Eleftheria Tsakalozou
- Office of Research and Standards, Office of Generic Drugs, Center for Drug Evaluation and Research, U.S. Food and Drug Administration (FDA), Silver Spring, Maryland, USA
| | | | | | | | - Priyanka Ghosh
- Office of Research and Standards, Office of Generic Drugs, Center for Drug Evaluation and Research, U.S. Food and Drug Administration (FDA), Silver Spring, Maryland, USA
| | - Khondoker Alam
- Office of Research and Standards, Office of Generic Drugs, Center for Drug Evaluation and Research, U.S. Food and Drug Administration (FDA), Silver Spring, Maryland, USA
| | - Sam G Raney
- Office of Research and Standards, Office of Generic Drugs, Center for Drug Evaluation and Research, U.S. Food and Drug Administration (FDA), Silver Spring, Maryland, USA
| | | | - Sebastian Polak
- Simcyp Division, Certara UK, Sheffield, UK.,Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland
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4
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Park S. Biochemical, structural and physical changes in aging human skin, and their relationship. Biogerontology 2022; 23:275-288. [PMID: 35292918 DOI: 10.1007/s10522-022-09959-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 02/25/2022] [Indexed: 11/02/2022]
Abstract
Skin is the largest organ of the human body, having the purpose of regulating temperature, protecting us from microbes or mechanical shocks, and allowing the sensations from touch. It is generally accepted that aging induces profound changes in the skin's biochemical, structural and physical properties, which can lead to impaired biological functions and/or diverse diseases. So far, the effects of aging on these skin properties have been well documented. However, very few studies have focused exclusively on the relationship among these critical properties in the aging process, which is this review's primary focus. Many in vivo, ex vivo, and in vitro techniques have been previously used to characterize these properties of the skin. This review aims to provide a comprehensive overview on the effects of aging on the changes in biochemical, structural, and physical properties, and explore the potential mechanisms of skin with the relation between these properties. First, we review different or contradictory results of aging-related changes in representative parameters of each property, including the interpretations of the findings. Next, we discuss the need for a standardized method to characterize aging-related changes in these properties, to improve the way of defining age-property relationship. Moreover, potential mechanisms based on the previous results are explored by linking the biochemical, structural, and physical properties. Finally, the need to study changes of various functional properties in the separate skin layers is addressed. This review can help understand the underlying mechanism of aging-related alterations, to improve the evaluation of the aging process and guide effective treatment strategies for aging-related diseases.
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Affiliation(s)
- Seungman Park
- Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD, 21218, USA. .,Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA.
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5
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Li N, Zang H, Sun H, Jiao X, Wang K, Liu TCY, Meng Y. A Noninvasive Accurate Measurement of Blood Glucose Levels with Raman Spectroscopy of Blood in Microvessels. Molecules 2019; 24:molecules24081500. [PMID: 30999565 PMCID: PMC6514896 DOI: 10.3390/molecules24081500] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 04/12/2019] [Accepted: 04/13/2019] [Indexed: 11/16/2022] Open
Abstract
Raman spectra of human skin obtained by laser excitation have been used to non-invasively detect blood glucose. In previous reports, however, Raman spectra thus obtained were mainly derived from the epidermis and interstitial fluid as a result of the shallow penetration depth of lasers in skin. The physiological process by which glucose in microvessels penetrates into the interstitial fluid introduces a time delay, which inevitably introduces errors in transcutaneous measurements of blood glucose. We focused the laser directly on the microvessels in the superficial layer of the human nailfold, and acquired Raman spectra with multiple characteristic peaks of blood, which indicated that the spectra obtained predominantly originated from blood. Incorporating a multivariate approach combining principal component analysis (PCA) and back propagation artificial neural network (BP-ANN), we performed noninvasive blood glucose measurements on 12 randomly selected volunteers, respectively. The mean prediction performance of the 12 volunteers was obtained as an RMSEP of 0.45 mmol/L and R2 of 0.95. It was no time lag between the predicted blood glucose and the actual blood glucose in the oral glucose tolerance test (OGTT). We also applied the procedure to data from all 12 volunteers regarded as one set, and the total predicted performance was obtained with an RMSEP of 0.27 mmol/L and an R2 of 0.98, which is better than that of the individual model for each volunteer. This suggested that anatomical differences between volunteer fingernails do not reduce the prediction accuracy and 100% of the predicted glucose concentrations fall within Region A and B of the Clarke error grid, allowing acceptable predictions in a clinically relevant range. The Raman spectroscopy detection of blood glucose from microvessels is of great significance of non-invasive blood glucose detection of Raman spectroscopy. This innovative method may also facilitate non-invasive detection of other blood components.
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Affiliation(s)
- Nan Li
- MOE Key Laboratory of Laser Life Science & Laboratory of Photonic Chinese Medicine, College of Biophotonics, South China Normal University, Guangdong 510631, China.
| | - Hang Zang
- MOE Key Laboratory of Laser Life Science & Laboratory of Photonic Chinese Medicine, College of Biophotonics, South China Normal University, Guangdong 510631, China.
| | - Huimin Sun
- MOE Key Laboratory of Laser Life Science & Laboratory of Photonic Chinese Medicine, College of Biophotonics, South China Normal University, Guangdong 510631, China.
| | - Xianzhi Jiao
- MOE Key Laboratory of Laser Life Science & Laboratory of Photonic Chinese Medicine, College of Biophotonics, South China Normal University, Guangdong 510631, China.
| | - Kangkang Wang
- MOE Key Laboratory of Laser Life Science & Laboratory of Photonic Chinese Medicine, College of Biophotonics, South China Normal University, Guangdong 510631, China.
| | - Timon Cheng-Yi Liu
- MOE Key Laboratory of Laser Life Science & Laboratory of Photonic Chinese Medicine, College of Biophotonics, South China Normal University, Guangdong 510631, China.
| | - Yaoyong Meng
- MOE Key Laboratory of Laser Life Science & Laboratory of Photonic Chinese Medicine, College of Biophotonics, South China Normal University, Guangdong 510631, China.
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Ray TR, Choi J, Bandodkar AJ, Krishnan S, Gutruf P, Tian L, Ghaffari R, Rogers JA. Bio-Integrated Wearable Systems: A Comprehensive Review. Chem Rev 2019; 119:5461-5533. [PMID: 30689360 DOI: 10.1021/acs.chemrev.8b00573] [Citation(s) in RCA: 434] [Impact Index Per Article: 86.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Bio-integrated wearable systems can measure a broad range of biophysical, biochemical, and environmental signals to provide critical insights into overall health status and to quantify human performance. Recent advances in material science, chemical analysis techniques, device designs, and assembly methods form the foundations for a uniquely differentiated type of wearable technology, characterized by noninvasive, intimate integration with the soft, curved, time-dynamic surfaces of the body. This review summarizes the latest advances in this emerging field of "bio-integrated" technologies in a comprehensive manner that connects fundamental developments in chemistry, material science, and engineering with sensing technologies that have the potential for widespread deployment and societal benefit in human health care. An introduction to the chemistries and materials for the active components of these systems contextualizes essential design considerations for sensors and associated platforms that appear in following sections. The subsequent content highlights the most advanced biosensors, classified according to their ability to capture biophysical, biochemical, and environmental information. Additional sections feature schemes for electrically powering these sensors and strategies for achieving fully integrated, wireless systems. The review concludes with an overview of key remaining challenges and a summary of opportunities where advances in materials chemistry will be critically important for continued progress.
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Affiliation(s)
- Tyler R Ray
- Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208 , United States
| | - Jungil Choi
- Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208 , United States
| | - Amay J Bandodkar
- Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208 , United States
| | - Siddharth Krishnan
- Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208 , United States
| | - Philipp Gutruf
- Department of Biomedical Engineering University of Arizona Tucson , Arizona 85721 , United States
| | - Limei Tian
- Department of Biomedical Engineering , Texas A&M University , College Station , Texas 77843 , United States
| | - Roozbeh Ghaffari
- Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208 , United States
| | - John A Rogers
- Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208 , United States
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Krishnan SR, Su CJ, Xie Z, Patel M, Madhvapathy SR, Xu Y, Freudman J, Ng B, Heo SY, Wang H, Ray TR, Leshock J, Stankiewicz I, Feng X, Huang Y, Gutruf P, Rogers JA. Wireless, Battery-Free Epidermal Electronics for Continuous, Quantitative, Multimodal Thermal Characterization of Skin. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1803192. [PMID: 30369049 DOI: 10.1002/smll.201803192] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 09/03/2018] [Indexed: 05/26/2023]
Abstract
Precise, quantitative measurements of the thermal properties of human skin can yield insights into thermoregulatory function, hydration, blood perfusion, wound healing, and other parameters of clinical interest. The need for wired power supply systems and data communication hardware limits, however, practical applicability of existing devices designed for measurements of this type. Here, a set of advanced materials, mechanics designs, integration schemes, and wireless circuits is reported as the basis for wireless, battery-free sensors that softly interface to the skin to enable precise measurements of its temperature and thermal transport properties. Calibration processes connect these parameters to the hydration state of the skin, the dynamics of near-surface flow through blood vessels and implanted catheters, and to recovery processes following trauma. Systematic engineering studies yield quantitative metrics in precision and reliability in real-world conditions. Evaluations on five human subjects demonstrate the capabilities in measurements of skin hydration and injury, including examples of continuous wear and monitoring over a period of 1 week, without disrupting natural daily activities.
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Affiliation(s)
- Siddharth R Krishnan
- Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Simpson Querrey Institute for BioNanotechnology, Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL, 60208, USA
| | - Chun-Ju Su
- Department of Materials Science and Engineering, Simpson Querrey Institute for BioNanotechnology, Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL, 60208, USA
| | - Zhaoqian Xie
- Department of Civil and Environmental Engineering, Mechanical Engineering, Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Manish Patel
- Department of Materials Science and Engineering, Simpson Querrey Institute for BioNanotechnology, Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL, 60208, USA
| | - Surabhi R Madhvapathy
- Department of Materials Science and Engineering, Simpson Querrey Institute for BioNanotechnology, Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL, 60208, USA
| | - Yeshou Xu
- Department of Civil and Environmental Engineering, Mechanical Engineering, Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
- Key Laboratory of C&PC Structures of the Ministry of Education, Southeast University, Nanjing, 210096, China
| | - Juliet Freudman
- Department of Biomedical Engineering, Simpson Querrey Institute for BioNanotechnology, Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL, 60208, USA
| | - Barry Ng
- Department of Materials Science and Engineering, Simpson Querrey Institute for BioNanotechnology, Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL, 60208, USA
| | - Seung Yun Heo
- Department of Biomedical Engineering, Simpson Querrey Institute for BioNanotechnology, Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL, 60208, USA
| | - Heling Wang
- Department of Civil and Environmental Engineering, Mechanical Engineering, Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Tyler R Ray
- Department of Materials Science and Engineering, Simpson Querrey Institute for BioNanotechnology, Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL, 60208, USA
| | - John Leshock
- Department of Biomedical Engineering, Simpson Querrey Institute for BioNanotechnology, Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL, 60208, USA
| | - Izabela Stankiewicz
- Department of Biomedical Engineering, Simpson Querrey Institute for BioNanotechnology, Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL, 60208, USA
| | - Xue Feng
- AML, Department of Engineering Mechanics, Center for Mechanics and Materials, Tsinghua University, Beijing, 100084, China
| | - Yonggang Huang
- Department of Civil and Environmental Engineering, Mechanical Engineering, Materials Science and Engineering, Center of Bio-integrated electronics, Northwestern University, Evanston, IL, 60208, USA
| | - Philipp Gutruf
- Department of Biomedical Engineering, University of Arizona, Tucson, AZ, 85721, USA
| | - John A Rogers
- Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Materials Science and Engineering, Biomedical Engineering, Chemistry, Mechanical Engineering, Electrical Engineering and Computer Science and Neurological Surgery, McCormick School of Engineering and Feinberg School of Medicine, Simpson Querrey Institute for BioNanotechnology, Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL, 60208, USA
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Krishnan S, Shi Y, Webb RC, Ma Y, Bastien P, Crawford KE, Wang A, Feng X, Manco M, Kurniawan J, Tir E, Huang Y, Balooch G, Pielak RM, Rogers JA. Multimodal epidermal devices for hydration monitoring. MICROSYSTEMS & NANOENGINEERING 2017; 3:17014. [PMID: 31057861 PMCID: PMC6444991 DOI: 10.1038/micronano.2017.14] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 12/10/2016] [Accepted: 01/09/2017] [Indexed: 05/04/2023]
Abstract
Precise, quantitative in vivo monitoring of hydration levels in the near surface regions of the skin can be useful in preventing skin-based pathologies, and regulating external appearance. Here we introduce multimodal sensors with important capabilities in this context, rendered in soft, ultrathin, 'skin-like' formats with numerous advantages over alternative technologies, including the ability to establish intimate, conformal contact without applied pressure, and to provide spatiotemporally resolved data on both electrical and thermal transport properties from sensitive regions of the skin. Systematic in vitro studies and computational models establish the underlying measurement principles and associated approaches for determination of temperature, thermal conductivity, thermal diffusivity, volumetric heat capacity, and electrical impedance using simple analysis algorithms. Clinical studies on 20 patients subjected to a variety of external stimuli validate the device operation and allow quantitative comparisons of measurement capabilities to those of existing state-of-the-art tools.
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Affiliation(s)
- Siddharth Krishnan
- Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Yunzhou Shi
- L’Oreal Tech Incubator, California Research Center, 953 Indiana Street, San Francisco, CA 94107, USA
| | - R. Chad Webb
- Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Yinji Ma
- Department of Civil and Environmental Engineering, Mechanical Engineering, Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA
- Department of Engineering Mechanics, Center for Mechanics and Materials, Tsinghua University, Beijing 100084, China
| | - Philippe Bastien
- L’Oréal Research and Innovation, 1 Avenue Eugène Schuller, Aulnay sous Bois 93601, France
| | - Kaitlyn E. Crawford
- Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Ao Wang
- Department of Civil and Environmental Engineering, Mechanical Engineering, Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Xue Feng
- Department of Engineering Mechanics, Center for Mechanics and Materials, Tsinghua University, Beijing 100084, China
| | - Megan Manco
- L’Oréal Early Clinical, 133 Terminal Avenue, Clark, NJ 07066, USA
| | - Jonas Kurniawan
- Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Edward Tir
- Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Yonggang Huang
- Department of Civil and Environmental Engineering, Mechanical Engineering, Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Guive Balooch
- L’Oreal Tech Incubator, California Research Center, 953 Indiana Street, San Francisco, CA 94107, USA
| | - Rafal M. Pielak
- L’Oreal Tech Incubator, California Research Center, 953 Indiana Street, San Francisco, CA 94107, USA
- ()
| | - John A. Rogers
- Departments of Materials Science and Engineering, Biomedical Engineering, Chemistry, Mechanical Engineering, Electrical Engineering and Computer Science, and Neurological Surgery; Center for Bio-Integrated Electronics; Simpson Querrey Institute for Nano/biotechnology; Northwestern University, Evanston, IL 60208, USA
- ()
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Laistler E, Poirier-Quinot M, Lambert SA, Dubuisson RM, Girard OM, Moser E, Darrasse L, Ginefri JC. In vivo MR imaging of the human skin at subnanoliter resolution using a superconducting surface coil at 1.5 Tesla. J Magn Reson Imaging 2013; 41:496-504. [PMID: 24382749 DOI: 10.1002/jmri.24549] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2012] [Accepted: 11/18/2013] [Indexed: 11/06/2022] Open
Abstract
PURPOSE To demonstrate the feasibility of a highly sensitive superconducting surface coil for microscopic MRI of the human skin in vivo in a clinical 1.5 Tesla (T) scanner. MATERIALS AND METHODS A 12.4-mm high-temperature superconducting coil was used at 1.5T for phantom and in vivo skin imaging. Images were inspected to identify fine anatomical skin structures. Signal-to-noise ratio (SNR) improvement by the high-temperature superconducting (HTS) coil, as compared to a commercial MR microscopy coil was quantified from phantom imaging; the gain over a geometrically identical coil made from copper (cooled or not) was theoretically deduced. Noise sources were identified to evaluate the potential of HTS coils for future studies. RESULTS In vivo skin images with isotropic 80 μm resolution were demonstrated revealing fine anatomical structures. The HTS coil improved SNR by a factor 32 over the reference coil in a nonloading phantom. For calf imaging, SNR gains of 380% and 30% can be expected over an identical copper coil at room temperature and 77 K, respectively. CONCLUSION The high sensitivity of HTS coils allows for microscopic imaging of the skin at 1.5T and could serve as a tool for dermatology in a clinical setting.
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Affiliation(s)
- Elmar Laistler
- IR4M (Imagerie par Résonance Magnétique Médicale et Multi-Modalités), UMR8081 Univ Paris Sud - CNRS, Orsay, France; Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria; MR Center of Excellence, Medical University of Vienna, Vienna, Austria
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11
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Calzolari L, Kastler A, Mac-Mary S, Humbert P, Kastler B, Aubry S. 3T-MRI analysis of epidermis and dermis moisturizing using the T2-mapping sequence. Skin Res Technol 2013; 19:152-4. [DOI: 10.1111/srt.12026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Adrian Kastler
- Radiologie; CHRU Besançon; France
- I4S Laboratory - EA 4268-IFR 133; University of Franche-comte; Besançon, France
| | - Sophie Mac-Mary
- Skinexigence; CHRU Besançon, France
- Research and Studies Center on the Integument (CERT); Clinical Investigation Center (CIC BT506); Department of Dermatology; CHRU Besançon, France
| | - Philippe Humbert
- Research and Studies Center on the Integument (CERT); Clinical Investigation Center (CIC BT506); Department of Dermatology; CHRU Besançon, France
- INSERM UMR1098, SFR FED 4234 IBCT, University of Franche-Comte; Besançon France
| | - Bruno Kastler
- Radiologie; CHRU Besançon; France
- I4S Laboratory - EA 4268-IFR 133; University of Franche-comte; Besançon, France
| | - Sebastien Aubry
- Radiologie; CHRU Besançon; France
- I4S Laboratory - EA 4268-IFR 133; University of Franche-comte; Besançon, France
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13
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Sans N, Faruch M, Chiavassa-Gandois H, Ribes CLCD, Paul C, Railhac JJ. High-resolution magnetic resonance imaging in study of the skin: Normal patterns. Eur J Radiol 2011; 80:e176-81. [DOI: 10.1016/j.ejrad.2010.06.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Revised: 05/14/2010] [Accepted: 06/02/2010] [Indexed: 10/19/2022]
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14
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Wagner M, Mavon A, Haidara H, Vallat MF, Duplan H, Roucoules V. From contact angle titration to chemical force microscopy: a new route to assess the pH-dependent character of the stratum corneum. Int J Cosmet Sci 2011; 34:55-63. [DOI: 10.1111/j.1468-2494.2011.00681.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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15
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Groenendaal W, von Basum G, Schmidt KA, Hilbers PAJ, van Riel NAW. Quantifying the composition of human skin for glucose sensor development. J Diabetes Sci Technol 2010; 4:1032-40. [PMID: 20920423 PMCID: PMC2956818 DOI: 10.1177/193229681000400502] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Glucose is heterogeneously distributed within human skin. In order to develop a glucose measurement method for human skin, both a good quantification of the different compartments of human skin and an understanding of glucose transport processes are essential. This study focused on the composition of human skin. In addition, the extent to which intersubject variability in skin composition alters glucose dynamics in human skin was investigated. METHODS To quantify the composition of the three layers of human skin-epidermis, dermis, and adipose tissue-cell and blood vessel volumes were calculated from skin biopsies. These results were combined with data from the literature. The composition was applied as input for a previously developed computational model that calculates spatiotemporal glucose dynamics in human skin. The model was used to predict the physiological effects of intersubject variability in skin composition on glucose profiles in human skin. RESULTS According to the model, the lag time of glucose dynamics in the epidermis was sensitive to variation in the volumes of interstitial fluid, cells, and blood of all layers. Data showed most variation/uncertainty in the volume composition of the adipose tissue. This variability mainly influences the dynamics in the adipose tissue. CONCLUSIONS This study identified the intersubject variability in human skin composition. The study shows that this variability has significant influence on the glucose dynamics in human skin. In addition, it was determined which volumes are most critical for the quantification and interpretation of measurements in the different layers.
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Affiliation(s)
- Willemijn Groenendaal
- Department of Biomedical Engineering, Biomodeling and Bioinformatics Group, Eindhoven University of Technology, Eindhoven, The Netherlands.
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Nakagawa N, Matsumoto M, Sakai S. In vivomeasurement of the water content in the dermis by confocal Raman spectroscopy. Skin Res Technol 2010; 16:137-41. [DOI: 10.1111/j.1600-0846.2009.00410.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Aubry S, Casile C, Humbert P, Jehl J, Vidal C, Kastler B. Feasibility study of 3-T MR imaging of the skin. Eur Radiol 2009; 19:1595-603. [PMID: 19277676 DOI: 10.1007/s00330-009-1348-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Revised: 01/03/2009] [Accepted: 01/12/2009] [Indexed: 11/28/2022]
Abstract
The purpose of this study was to assess the quality of 3-T magnetic resonance (MR) imaging of the skin, to describe skin anatomy at 3 T and to discuss future prospects of skin MRI. A 7-cm single-element surface receiver coil was developed for our 3-T MRI system. Thin sections were obtained with a three-dimensional FIESTA acquisition sequence and a spin-echo T1-weighted sequence (SET1). Prospective analysis was performed twice by two radiologists independently. Thirty-six healthy volunteers were included and underwent MRI on the face and the calf. Image quality was assessed regarding visibility of skin layers and quantification of artefacts. High field strength MR enables imaging of the skin with a high spatial in-plane resolution (87-180 microm), the total examination lasting 15-20 min. Image quality was excellent for the calf (mean SET1 quality = 96%) with a high intra- and interobserver correlation (SET1 kappa coefficient concerning visibility of epidermis, dermis and hypodermis > or = 0.84). Motion artefacts resulted in a small loss of quality and reproducibility for the face. In conclusion, 3-T MR allows high spatial resolution imaging of the skin and can potentially provide an accurate noninvasive means of analysing the skin.
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Affiliation(s)
- Sébastien Aubry
- Service de Radiologie A, CHU Jean Minjoz, Boulevard Flemming, 25030, Besançon Cedex, France.
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Denis A, Loustau O, Chiavassa-Gandois H, Vial J, Lalande Champetier de Ribes C, Railhac JJ, Sans N. [High resolution MR imaging of the skin: normal imaging features]. ACTA ACUST UNITED AC 2008; 89:873-9. [PMID: 18772749 DOI: 10.1016/s0221-0363(08)73875-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
PURPOSE To describe the qualitative and quantitative MR imaging features of normal skin. MATERIALS AND METHODS Thirty-one normal subjects underwent MR evaluation on a 1.5 Tesla magnet using a dedicated coil. Several skin sites were evaluated (back at the scapular level, posterior calf and inferior heel). Two pulse sequences were acquired: a SE T1W and a gradient-echo sequence (FIESTA). Qualitative and quantitative analysis was performed for all three sites. RESULTS In normal subjects, the different skin layers (callus, epidermis, dermis, hypodermis and pilosebaceous follicles) can be separated and measured on MR. Epidermis and hypodermis are hyperintense whereas dermis is hypointense. Our results confirm the presence of qualitative and quantitative variations between different skin regions. In some cases, a differentiation between papillary and reticular dermis can be achieved. Pilosebaceous follicles and the deep vascular network were clearly depicted on the FIESTA sequence. Measurements for each skin layer were compared based on sex, site and MR pulse sequence. CONCLUSION MRI provides evaluation of the different skin layers, epidermis, dermis, and hypodermis, and their different components.
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Affiliation(s)
- A Denis
- Service de Radiologie et Imagerie Médicale, Centre Hospitalier Universitaire Purpan, Place du Dr Baylac, 31059 Toulouse Cedex 9
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Gerhardt LC, Strässle V, Lenz A, Spencer ND, Derler S. Influence of epidermal hydration on the friction of human skin against textiles. J R Soc Interface 2008; 5:1317-28. [PMID: 18331977 DOI: 10.1098/rsif.2008.0034] [Citation(s) in RCA: 149] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Friction and shear forces, as well as moisture between the human skin and textiles are critical factors in the formation of skin injuries such as blisters, abrasions and decubitus. This study investigated how epidermal hydration affects the friction between skin and textiles.The friction between the inner forearm and a hospital fabric was measured in the natural skin condition and in different hydration states using a force plate. Eleven males and eleven females rubbed their forearm against the textile on the force plate using defined normal loads and friction movements. Skin hydration and viscoelasticity were assessed by corneometry and the suction chamber method, respectively.In each individual, a highly positive linear correlation was found between skin moisture and friction coefficient (COF). No correlation was observed between moisture and elasticity, as well as between elasticity and friction. Skin viscoelasticity was comparable for women and men. The friction of female skin showed significantly higher moisture sensitivity. COFs increased typically by 43% (women) and 26% (men) when skin hydration varied between very dry and normally moist skin. The COFs between skin and completely wet fabric were more than twofold higher than the values for natural skin rubbed on a dry textile surface.Increasing skin hydration seems to cause gender-specific changes in the mechanical properties and/or surface topography of human skin, leading to skin softening and increased real contact area and adhesion.
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Affiliation(s)
- L-C Gerhardt
- Laboratory for Protection and Physiology, EMPA, Swiss Federal Laboratories for Materials Testing and Research, St Gallen, Switzerland.
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20
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Rodríguez I, Pérez-Rial S, González-Jimenez J, Pérez-Sánchez J, Herranz F, Beckmann N, Ruíz-Cabello J. Magnetic resonance methods and applications in pharmaceutical research. J Pharm Sci 2008; 97:3637-65. [PMID: 18228597 DOI: 10.1002/jps.21281] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
This review presents an overview of some recent magnetic resonance (MR) techniques for pharmaceutical research. MR is noninvasive, and does not expose subjects to ionizing radiation. Some methods that have been used in pharmaceutical research MR include magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI) methods, among them, diffusion-weighted MRI, perfusion-weighted MRI, functional MRI, molecular imaging and contrast-enhance MRI. Some applications of MR in pharmaceutical research include MR in metabonomics, in vivo MRS, studies in cerebral ischemia and infarction, degenerative joint diseases, oncology, cardiovascular disorders, respiratory diseases and skin diseases. Some of these techniques, such as cardiac and joint imaging, or brain fMRI are standard, and are providing relevant data routinely. Skin MR and hyperpolarized gas lung MRI are still experimental. In conclusion, considering the importance of finding and characterizing biomarkers for improved drug evaluation, it can be expected that the use of MR techniques in pharmaceutical research is going to increase in the near future.
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Affiliation(s)
- I Rodríguez
- Grupo de Resonancia Magnética, Instituto de Estudios Biofuncionales, Universidad Complutense de Madrid, Paseo Juan XXIII 1, Madrid 28040, Spain
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21
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Groenendaal W, Schmidt KA, von Basum G, van Riel NAW, Hilbers PAJ. Modeling glucose and water dynamics in human skin. Diabetes Technol Ther 2008; 10:283-93. [PMID: 18715202 DOI: 10.1089/dia.2007.0290] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Glucose is heterogeneously distributed in the different physiological compartments in the human skin. Therefore, for the development of a noninvasive measurement method, both a good quantification of the different compartments of human skin and an understanding of glucose transport processes are important. METHODS The composition of human skin was quantified by histology research. Based on this information a mathematical model was developed to simulate glucose dynamics in human skin. RESULTS The model predicts dynamically glucose concentrations in the different layers of the skin as a result of changes in blood glucose concentration. The model was validated with published time course data of blood and interstitial fluid glucose during a clamp study with three different set points for blood glucose, and model outcomes were compared to measurements for the lag time and gradient. According to the model, glucose in the interstitial fluid of the dermis best matches the amplitude and dynamics of blood glucose. CONCLUSIONS The new data obtained from quantitative histology appeared crucial for the model. The proposed model was successfully validated. This result was obtained without tuning or fitting of any parameter. It was shown how the model can be used to set standards for measurements and to define the best measurement depth for noninvasive glucose monitoring.
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Affiliation(s)
- W Groenendaal
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
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Chrit L, Bastien P, Biatry B, Simonnet JT, Potter A, Minondo AM, Flament F, Bazin R, Sockalingum GD, Leroy F, Manfait M, Hadjur C. In vitro and in vivo confocal Raman study of human skin hydration: assessment of a new moisturizing agent, pMPC. Biopolymers 2007; 85:359-69. [PMID: 17143858 DOI: 10.1002/bip.20644] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The hydration capacities of a biomimetic polymer, 2-methacryloyloxethylphosphorylcholine polymer (pMPC), alone and microencapsulated, in association with another well known hydrating polymer, Hyaluronic acid, were investigated in vitro on skin models and in vivo on volunteers by using confocal Raman microspectroscopy. The hydration impact and the relative water content in the Stratum corneum were calculated from the Raman spectra using the OH (water)/CH3 (protein) ratio. Moreover, the follow-up of the presence of pMPC through the Stratum corneum was possible with confocal Raman microspectroscopy, using a characteristic vibration of pMPC, different from that of the encapsulating material. From our in vitro measurements, the improved hydration of the Stratum corneum was confirmed by the use of the encapsulated form of pMPC, which was higher when combined with Hyaluronic acid. On the basis of these in vitro findings, we validated this trend in in vivo measurements on 26 volunteers, and found a good correlation with the in vitro results. Mechanical and ultrastructural studies have been carried out to demonstrate the positive effects of the pMPC on the Stratum corneum function, namely the interaction with lamellar lipids and the plasticizing effects, which are both supposed to spell out the moisturizing effect. This study demonstrates the efficiency of a original hydrating agent, pMPC, entrapped with Hyaluronic acid in a new type of microcapsules by the use of a novel tool developed for both in vitro and in vivo approaches. This indicates a new step to evaluate and improve new moisturizers in response to the cosmetics or dermatologic demands.
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Naito S, Min YK, Sugata K, Osanai O, Kitahara T, Hiruma H, Hamaguchi H. In vivomeasurement of human dermis by 1064 nm-excited fiber Raman spectroscopy. Skin Res Technol 2007; 14:18-25. [DOI: 10.1111/j.1600-0846.2007.00255.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Bittoun J, Querleux B, Darrasse L. Advances in MR imaging of the skin. NMR IN BIOMEDICINE 2006; 19:723-30. [PMID: 17075954 DOI: 10.1002/nbm.1101] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
MR imaging of the skin is challenging because of the small size of the structures to be visualized. By increasing the gradient amplitude and/or duration, skin layers can be visualized with a voxel size of the order of 20 microm, clearly the smallest obtained for in vivo images in a whole-body imager. Currently, the gradient strength of most commercial systems enables acquisition of such a small voxel size, and the main difficulty has thus become to achieve sufficient detection sensitivity. The signal-to-noise ratio (SNR) can be increased either by increasing the magnetic field strength or by minimizing noise with small coils; cooling copper coils or superconducting coils can enhance the SNR by a factor of 3 or more. MR imaging, because of the large number of parameters it is able to measure, can provide more than the microscopic architecture of the skin: physical parameters such as relaxation times, magnetization transfer or diffusion, and chemical parameters such as the water and fat contents or phosphorus metabolism. In spite of the amount of information they have provided to date, MR imaging and spectroscopy have had limited clinical applications, mainly because cutaneous pathologies are easily accessible to the naked eye and surgery. However, MR technologies indeed represent powerful research tools to study normal and diseased skin.
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Affiliation(s)
- Jacques Bittoun
- U2R2M, CNRS-Université Paris-Sud, CIERM Hôpital Bicêtre, 94275 Le Kremlin-Bicêtre, France.
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25
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Kilpatrick-Liverman L, Kazmi P, Wolff E, Polefka TG. The use of near-infrared spectroscopy in skin care applications. Skin Res Technol 2006; 12:162-9. [PMID: 16827690 DOI: 10.1111/j.0909-752x.2006.00142.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Near-infrared (NIR) spectroscopy was used to document the skin water content as a function of product usage and changes in the % relative humidity (%RH) in vitro and in vivo. The objective of the investigation was to determine if the NIR could provide comparable skin water content information as that obtained using gravimetric, conductivity, or visual assessment methods without having to invoke complex chemometric calculations. METHODS NIR data were obtained using an NIR5000 spectrophotometer with a fiber optic probe (Smartprobe) attachment to complete the clinical studies and a Direct Contact Analyzer module to carry out the in vitro experiments. Conductivity measurements were completed using the Skicon 200, which measures conductance at a fixed frequency of 3.5 MHz. Three moisturization-based clinical studies were carried out assessing the NIR's ability to detect skin hydration changes. In Clinical Study A, NIR and Skicon data were collected for panelists who had only washed their outer calf with water over a 4-week period. During this time, the daily average %RH was recorded. In Clinical Study B, 10% solutions of glycerin, choline chloride, and the sodium salt of pyrrolidone carboxylic acid were applied to the panelist's outer calf and biophysical measurements were completed to assess the hydration and desorption properties of these humectants. In Clinical Study C, a 10% solution of choline chloride was applied to panelist's outer calf and the cumulative effect of using this product was evaluated over a 3-week period. For all in vitro studies, porcine skin was used as the substrate. RESULTS Comparable NIR, Skicon, and visual dryness results were obtained for most of the product usage-based clinical experiments completed. However, the NIR was particularly more effective at detecting skin water content differences as a function of %RH changes. In the absence of abrupt (>50%) relative humidity variations, there was a direct correlation between the NIR readings and the %RH (R(2)=0.83) unlike what was observed for the Skicon measurements (R(2)=0.22). CONCLUSIONS NIR spectroscopy demonstrated the changes in the skin water content as a function of product usage; the results were consistent with those obtained using the Skicon conductivity meter and visual dryness assessment scores. More importantly, the differences detected were obtained without having to use chemometric manipulations in the data analysis as is the common practice. Of all the methods used, the NIR gave the best linear regression for %RH-induced skin water content changes.
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Chrit L, Bastien P, Sockalingum GD, Batisse D, Leroy F, Manfait M, Hadjur C. An in vivo Randomized Study of Human Skin Moisturization by a New Confocal Raman Fiber-Optic Microprobe: Assessment of a Glycerol-Based Hydration Cream. Skin Pharmacol Physiol 2006; 19:207-15. [PMID: 16679823 DOI: 10.1159/000093116] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2005] [Accepted: 11/17/2005] [Indexed: 11/19/2022]
Abstract
BACKGROUND In a recent study, we demonstrated the ability of the new confocal Raman microprobe to investigate molecular and structural human skin composition under in vivo conditions. Experiments were performed at different anatomical sites, different layers, and with intervolunteer comparison. We also carried out feasibility tests using this probe to determine depth profiles of water content within the skin. OBJECTIVE In the present investigation we employed this confocal Raman optical microprobe to rigorously objectify the resulting hydration capacities after application of a moisturizing enhancer. METHOD The in vivo experiments were performed on 26 healthy volunteers and measurements were undertaken on six areas of the volar forearm after a randomized application of hydrating agents. Responses were evaluated by calculating the water/protein band ratio, which determines the water content in the skin. RESULTS Data collected with the Raman microprobe showed significant changes between baseline values of control and treated skins. Statistical analysis performed on these data revealed an increase in skin moisture after application of a glycerol-based cream, which is the most widely used hydrating agent. CONCLUSION Our results demonstrate clearly the potentials of this confocal Raman microprobe in the screening of hydrating agents or molecules under in vivo conditions. In the cosmetics field, this promising and suitable technique will undoubtedly offer new opportunities of hydration skin test evaluation.
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Affiliation(s)
- L Chrit
- L'Oréal Recherche, Aulnay-sous-Bois, France
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Eikje NS, Ozaki Y, Aizawa K, Arase S. Fiber optic near-infrared Raman spectroscopy for clinical noninvasive determination of water content in diseased skin and assessment of cutaneous edema. JOURNAL OF BIOMEDICAL OPTICS 2005; 10:14013. [PMID: 15847594 DOI: 10.1117/1.1854682] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Currently, measuring Raman spectra of tissues of living patients online and in real time, collecting the spectra in a very short measurement time, and allowing diagnosis immediately after the spectrum is recorded from any body region, are specific advantages that fiber optic near-infrared Raman spectroscopy (NIR RS) might represent for in vivo clinical applications in dermatology. We discuss various methodological aspects and state of the art of fiber optic NIR RS in clinical and experimental dermatology to outline its present advantages and disadvantages for measuring skin in vivo, particularly its water content. Fiber optic NIR Fourier transform (FT) RS has been introduced to dermatological diagnostics to obtain information regarding the molecular composition of the skin up to several hundred micrometers below the skin surface in a relatively fast nondestructive manner. This has been especially important for probing for in vivo assessment of cutaneous (intradermal) edema in patients patch test reactions. Fiber optic NIR FT Raman spectrometers still require further technological developments and optimization, extremely accurate water concentration determination and its intensity calculation in skin tissue, and for clinical applications, a reduction of measurement time and their size. Another promising option could be the possibility of applying mobile and compact fiber optic charge-coupled device (CCD)-based equipment in clinical dermatology.
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Affiliation(s)
- Natalja Skrebova Eikje
- Tokushima University, Department of Dermatology, School of Medicine, Tokushima 770-8503, Japan.
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28
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Thali MJ, Dirnhofer R, Becker R, Oliver W, Potter K. Is ‘virtual histology’ the next step after the ‘virtual autopsy’? Magnetic resonance microscopy in forensic medicine. Magn Reson Imaging 2004; 22:1131-8. [PMID: 15528000 DOI: 10.1016/j.mri.2004.08.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2004] [Accepted: 08/11/2004] [Indexed: 11/29/2022]
Abstract
AIM The study aimed to validate magnetic resonance microscopy (MRM) studies of forensic tissue specimens (skin samples with electric injury patterns) against the results from routine histology. METHODS AND RESULTS Computed tomography and magnetic resonance imaging are fast becoming important tools in clinical and forensic pathology. This study is the first forensic application of MRM to the analysis of electric injury patterns in human skin. Three-dimensional high-resolution MRM images of fixed skin specimens provided a complete 3D view of the damaged tissues at the site of an electric injury as well as in neighboring tissues, consistent with histologic findings. The image intensity of the dermal layer in T2-weighted MRM images was reduced in the central zone due to carbonization or coagulation necrosis and increased in the intermediate zone because of dermal edema. A subjacent blood vessel with an intravascular occlusion supports the hypothesis that current traveled through the vascular system before arcing to ground. CONCLUSION High-resolution imaging offers a noninvasive alternative to conventional histology in forensic wound analysis and can be used to perform 3D virtual histology.
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Affiliation(s)
- M J Thali
- Institute of Forensic Medicine, University of Berne, IRM - Buehlstrasse 20, Berne CH-3012, Switzerland.
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Backhouse L, Dias M, Gorce JP, Hadgraft J, McDonald PJ, Wiechers JW. GARField magnetic resonance profiling of the ingress of model skin-care product ingredients into human skin in vitro. J Pharm Sci 2004; 93:2274-83. [PMID: 15295788 DOI: 10.1002/jps.20137] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A preliminary study of the ingress of mineral oil, decanol, and glycerine into samples of human abdominal skin tissue in vitro made using magnetic resonance profiling with a GARField magnet is reported. Two layers, each circa 50 microm thick and attributed to stratum corneum and viable epidermis, are spatially resolved. Clear differences are observed in the magnetic resonance response of these layers arising from the application of the model skin-care product ingredients. In the case of decanol and glycerine, it is suggested that the profiles show evidence for the effects of moisturization, as distinct from hydration. In the case of glycerine, the effective ingress diffusion coefficient is calculated to be 1.3 +/- 0.5 x 10(-9) cm2s(-1).
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Affiliation(s)
- L Backhouse
- School of Electronics and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
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30
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Mueller B, Anissimov YG, Roberts MS. Unexpected clobetasol propionate profile in human stratum corneum after topical application in vitro. Pharm Res 2004; 20:1835-7. [PMID: 14661929 DOI: 10.1023/b:pham.0000003382.20030.54] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE The validity of using drug amount-depth profiles in stratum corneum to predict uptake of clobetasol propionate into stratum corneum and its transport into deeper skin layers was investigated. METHODS In vitro diffusion experiments through human epidermis were carried out using Franz-type glass diffusion cells. A saturated solution of clobetasol propionate in 20% (V/V) aqueous propylene glycol was topically applied for 48 h. Steady state flux was calculated from the cumulative amount of drug permeated vs. time profile. Epidermal partitioning was conducted by applying a saturated drug solution to both sides of the epidermis and allowing time to equilibrate. The tape stripping technique was used to define drug concentration-depth profiles in stratum corneum for both the diffusion and equilibrium experiments. RESULTS The concentration-depth profile of clobetasol propionate in stratum corneum for the diffusion experiment is biphasic. A logarithmic decline of the drug concentration over the first four to five tape strips flattens to a relatively constant low concentration level in deeper layers. The drug concentration-depth profile for the equilibrium studies displays a similar shape. CONCLUSIONS The shape of the concentration-depth profile of clobetasol propionate is mainly because of the variable partitioning coefficient in different stratum corneum layers.
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Affiliation(s)
- Beat Mueller
- Department of Medicine, University of Queensland, Princess Alexandra Hospital, Woolloongabba, Australia
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31
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Mirrashed F, Sharp JC. In vivo quantitative analysis of the effect of hydration (immersion and Vaseline treatment) in skin layers using high-resolution MRI and magnetisation transfer contrast. Skin Res Technol 2004; 10:14-22. [PMID: 14731244 DOI: 10.1111/j.1600-0846.2004.00047.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND/AIMS Many claims are made as to the efficacy of topical preparations in moisturising the skin, yet most of these claims cannot be substantiated by scientific study for the skin layers beneath the stratum corneum, and yield no information on the remainder of the epidermis and dermis. This argues for an in vivo quantitative method for measuring the effect of water loading extended to various layers of the skin. METHODS Detailed high-resolution in vivo MRI studies of hydration and dehydration of finger pad skin layers were conducted on one normal subject using two moisturisation methods (topical white soft paraffin (Vaseline) and water immersion). The dehydration study was carried out immediately following removal from prolonged skin moisturisation. Inter-individual variability for skin hydration (group study) was studied in seven healthy volunteers at 0 and 7 h hydration with Vaseline. Location dependence in skin hydration was investigated on the same subject by looking into the hydration of forearm and finger pad skin. System stability and measurement reproducibility was verified through a detailed phantom study. RESULTS Images of normal and hydrated human skin were obtained in vivo at voxel dimensions of 50 micromx150 micromx1000 microm. The effect of hydration and dehydration as a function of exposure to moisturiser (i.e. water and Vaseline) on the image signal intensity, observed T1, and interaction of free and bound water in specific tissues were identified and correlated with existing physiological knowledge. Swelling of stratum corneum due to hydration was expressed as an in vivo model of tissue hydration. CONCLUSION Results of the dehydration study showed that the changes due to the previous hydration of the skin are reversible for all skin layers. For both moisturisation methods (i.e. Vaseline and skin bathing), the effects of hydration and dehydration on the skin were similar. The trends of the MRI parameters for finger pad and arm skin were similar. The group study showed low inter-subject variability of hydration on stratum corneum and epidermis.
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Affiliation(s)
- Fakhereh Mirrashed
- Institute for Biodiagnostics, National Research Council Canada, Winnipeg, Canada.
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32
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Kanikkannan N, Locke BR, Singh M. Effect of jet fuels on the skin morphology and irritation in hairless rats. Toxicology 2002; 175:35-47. [PMID: 12049834 DOI: 10.1016/s0300-483x(02)00087-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Jet A and JP-8 are the major jet fuels used in civilian and military (US Air Force) flights, respectively. JP-8+100 is a new jet fuel recently introduced by US Air Force in some of its locations. The purpose of this study was to investigate the effects of dermal exposure of jet fuels (Jet A, JP-8, and JP-8+100) on the skin morphology, barrier function, moisture content, blood flow, and skin irritation (erythema and edema) in hairless rats. Jet fuels were applied by both occlusive and unocclusive methods. The skin of treated and control (untreated) sites were excised and analyzed by magnetic resonance imaging (MRI) (500 MHz, 11.7 Tesla). Unocclusive application of JP-8, Jet A, and JP-8+100 increased the transepidermal water loss (TEWL) gradually and the values at 120 h were significantly greater than the baseline value (P<0.05). Both occlusive and unocclusive application of jet fuels decreased the skin moisture content significantly (P<0.05). Unocclusive application of JP-8, Jet A, and JP-8+100 increased the skin blood flow, though the values returned to the baseline levels within 24 h. Occlusive application of jet fuels (8 h/day for 2 days) caused a substantial increase in the skin blood flow and the values at 48 h were about 6-fold greater than the baseline value. Occlusive application of jet fuels caused a moderate to severe erythema and a moderate edema. MRI was used to obtain proton images and water self-diffusion maps of hairless rat skin exposed to jet fuel. Exposure to JP-8 showed the largest difference from the control with regards to visual observations of the stratum corneum and hair follicles, while JP-8+100 appeared to affect the hair follicle region. The results of the present study demonstrate that exposure to jet fuels can disrupt the skin barrier function, cause skin irritation, and alter the skin structure (stratum corneum and viable epidermis) and MRI can be used as a tool to investigate the alterations in the skin morphology after exposure to toxic chemicals.
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Affiliation(s)
- Narayanasamy Kanikkannan
- Division of Pharmaceutics, College of Pharmacy, Florida A & M University, Tallahassee, FL 32307, USA
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van Zuijlen PPM, Angeles AP, Kreis RW, Bos KE, Middelkoop E. Scar assessment tools: implications for current research. Plast Reconstr Surg 2002; 109:1108-22. [PMID: 11884845 DOI: 10.1097/00006534-200203000-00052] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Scarring is considered a major medical problem that leads to cosmetic and functional sequelae. Scar tissue is clinically distinguished from normal skin by an aberrant color, rough surface texture, increased thickness (hypertrophy), occurrence of contraction, and firmness. Marked histologic differences are the change in dermal architecture and the presence of cells such as the myofibroblast. Many assessment tools are available for analysis of pathologic conditions of the skin; however, there is no general agreement as to the most appropriate tools for evaluation of scar tissue. This review critically discusses currently available objective measurement tools, subjective assessment tools, and potential devices that may be available in the future for scar assessment.
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Affiliation(s)
- Paul P M van Zuijlen
- Burn Center, Department of Surgery, Red Cross Hospital, Vondellaan 13, 1942 LE Beverwijk, The Netherlands.
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Diridollou S, Maillet A, Pavy-Le Traon A, Louisy F, Black D, Berson M, Grégoire JM, Gall Y, Arbeille P. Use of thigh pressure cuffs to modulate simulated microgravity-induced changes in the skin measured with high-resolution B-scan ultrasound. EUROPEAN JOURNAL OF ULTRASOUND : OFFICIAL JOURNAL OF THE EUROPEAN FEDERATION OF SOCIETIES FOR ULTRASOUND IN MEDICINE AND BIOLOGY 2001; 13:215-26. [PMID: 11516633 DOI: 10.1016/s0929-8266(01)00135-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVE The aim of the present study was to evaluate the fluid shift in a simulated microgravity experiment and to test the use of thigh cuffs to help alleviate the problem. METHODS The change in skin thickness was assessed by a 20 MHz B-scan ultrasound device. This was performed on eight volunteers who underwent two successive 7-day periods of -6 degrees anti-orthostatic bed-rest, with or without the daytime use of thigh cuffs. The thigh cuffs were used to counteract the development of facial oedema. RESULTS In the control group (without thigh cuffs), the results showed a steady increase in skin thickness of the combined dermis and hypodermis of the forehead and a reduction of the thickness of this tissue on the tibia. For the countermeasure group, although thigh cuffs were only employed during the daytime - being removed at night - their use reduced the amplitude and kinetics of the fluid shift, resulting in greater beneficial effects at the end of the day than early in the morning. CONCLUSION These results of objective measurements of skin made using a non-invasive high frequency ultrasonography method confirm reports by cosmonauts of a reduction in facial oedema and a more 'comfortable' adaptation to microgravity by the use of thigh cuffs during space flight. This system is potentially promising for investigating fluid shifts in the skin and may prove useful in the evaluation of some oedematous skin diseases, as well as their therapy.
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Affiliation(s)
- S Diridollou
- Institut de Recherche Pierre FABRE, Centre Jean-Louis Alibert, Immeuble Zodiaque 2, 3 Passage de l'Europe. BP 4404, 31405 Toulouse, Cedex 4, France.
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35
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El Gammal S, El Gammal C, Kaspar K, Pieck C, Altmeyer P, Vogt M, Ermert H. Sonography of the skin at 100 MHz enables in vivo visualization of stratum corneum and viable epidermis in palmar skin and psoriatic plaques. J Invest Dermatol 1999; 113:821-9. [PMID: 10571740 DOI: 10.1046/j.1523-1747.1999.00795.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A main drawback of 20-25 MHz ultrasound units for skin imaging is their limited resolution. We used a transducer with a center frequency of 95 MHz and a resolution of 8.5 microm axially and 27 microm laterally - an almost 10-fold increase compared with 20 MHz. By means of a new scanning technology we reached a depth of field of 3.2 mm. We examined normal palmar skin, normal glabrous skin on the abdomen, the upper back, the calf and the dorsal forearm, and 35 lesions of psoriasis vulgaris. From 11 psoriatic plaques biopsies were taken for correlation with the sonograms. In normal palmar skin, the horny layer is represented as an echopoor band below the skin entry echo, traversed by echorich coils, which correspond to eccrine sweat gland ducts. The thickness of this band significantly increases after occlusive application of petrolatum. Its lower border is defined by an echorich line, representing the stratum corneum/stratum Malpighii-interface. Underneath, a second echopoor band is visible, which corresponds to the viable epidermis plus the papillary dermis, bordered by the scattered echo reflexes of the reticular dermis. This band is also visible in glabrous skin; however, the stratum corneum cannot be detected. In psoriatic lesions, the thickened horny layer appears echorich; after application of petrolatum, its echodensity decreases. Below, the acanthotic epidermis plus the dermis with the inflammatory infiltrate are represented as an echopoor band. There is an excellent correlation between the sonometric thickness of this band and the histometric thickness of the acanthosis plus the infiltrated dermis. Our results show that 100 MHz sonography is a valuable tool for in vivo examination of the upper skin layers.
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Affiliation(s)
- S El Gammal
- Dermatological Clinic of the Ruhr-University Bochum, Germany.
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36
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Pagnoni A, Knuettel A, Welker P, Rist M, Stoudemayer T, Kolbe L, Sadiq I, Kligman AM. Optical coherence tomography in dermatology. Skin Res Technol 1999. [DOI: 10.1111/j.1600-0846.1999.tb00120.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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37
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Abstract
A spectroscopic imaging technique with high spatial resolution was used for the study of human skin in vivo. The measurements were performed using a whole-body magnetic resonance system (1.5 T) with standard gradients and a standard 8-cm diameter circular surface coil. A decisive gain in signal-to-noise ratio was achieved by reducing the receiver bandwidth of the imaging system to values less than +/-5 kHz. The chemical shift misregistration was eliminated by post-detection data processing. The method was tested on different kinds of skin, on the foot sole and head. Water, fat, and chemical shift artifact-free images were obtained with resolution 0.107 x 0.143 mm in plane and slice thickness 1 mm. A major advantage of the spectroscopic imaging procedure is that the pulse sequence can be optimized for the maximum signal-to-noise ratio. There is no need for special modification of the sequence to circumvent the chemical shift artifacts (water, fat suppression, etc.).
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Affiliation(s)
- J Weis
- Department of Diagnostic Radiology, University Hospital, Uppsala, Sweden.
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38
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Rudin M, Beckmann N, Porszasz R, Reese T, Bochelen D, Sauter A. In vivo magnetic resonance methods in pharmaceutical research: current status and perspectives. NMR IN BIOMEDICINE 1999; 12:69-97. [PMID: 10392805 DOI: 10.1002/(sici)1099-1492(199904)12:2<69::aid-nbm548>3.0.co;2-d] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In the last decade, in vivo MR methods have become established tools in the drug discovery and development process. In this review, several successful and potential applications of MRI and MRS in stroke, rheumatoid and osteo-arthritis, oncology and cardiovascular disorders are dealt with in detail. The versatility of the MR approach, allowing the study of various pathophysiological aspects in these disorders, is emphasized. New indication areas, for the characterization of which MR methods have hardly been used up to now, such as respiratory, gastro-intestinal and skin diseases, are outlined in a subsequent section. A strength of MRI, being a non-invasive imaging modality, is the ability to provide functional, i.e. physiological, readouts. Functional MRI examples discussed are the analysis of heart wall motion, perfusion MRI, tracer uptake and clearance studies, and neuronal activation studies. Functional information may also be derived from experiments using target-specific contrast agents, which will become important tools in future MRI applications. Finally the role of MRI and MRS for characterization of transgenic and knock-out animals, which have become a key technology in modern pharmaceutical research, is discussed. The advantages of MRI and MRS are versatility, allowing a comprehensive characterization of a diseased state and of the drug intervention, and non-invasiveness, which is of relevance from a statistical, economical and animal welfare point of view. Successful applications in drug discovery exploit one or several of these aspects. In addition, the link between preclinical and clinical studies makes in vivo MR methods highly attractive methods for pharmaceutical research.
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Affiliation(s)
- M Rudin
- Core Technologies Area, Novartis Pharma Research, Basel, Switzerland.
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Idy-Peretti I, Bittoun J, Alliot FA, Richard SB, Querleux BG, Cluzan RV. Lymphedematous skin and subcutis: in vivo high resolution magnetic resonance imaging evaluation. J Invest Dermatol 1998; 110:782-7. [PMID: 9579546 DOI: 10.1046/j.1523-1747.1998.00184.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Physico-chemical and morphologic parameters of skin layers and subcutaneous tissue in lymphedematous limb were studied in vivo using magnetic resonance imaging. High resolution images were obtained with a depth resolution of about 70 microm, using a specific surface gradient coil specially designed for skin imaging and connected to a standard whole-body imager at 1.5 T. Twenty-one patients with unilateral lower extremity lymphedema (11 primary and 10 secondary) were examined. Skin thickness, relaxation times, and relative proton density were calculated in lymphedematous limbs and in contralateral extremities. In diseased limbs, the average skin thickness (2.17 mm) was significantly larger (p = 1.5 x 10(-4)) than that of contralateral limb (1.14 mm). Major cutaneous alterations due to lymphedema took place in dermis. In lymphedematous dermis, the significant increase of relaxation time values could be due to a shift in the equilibrium of water inside this tissue in relation to the interactions between macromolecules and water molecules. In lymphedematous epidermis our results showed an increase in the number of free water protons. Information about water and fat distribution in lymphedema was also obtained using chemical shift weighted images. Our results demonstrated a water retention diffusely spread over the entire dermis, and an important fluid retention located in the interlobular spacing and beside the superficial fascia. Inside the subcutis, the mean thickness of the superficial fat lobules was increased more than that of the deep fat lobules. From all the various measurements we could not distinguish primary from secondary lymphedema.
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Affiliation(s)
- I Idy-Peretti
- Department of Magnetic Resonance Imaging, Hôpital Nord Amiens, France
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Song HK, Wehrli FW. Variable TE gradient and spin echo sequences for in vivo MR microscopy of short T2 species. Magn Reson Med 1998; 39:251-8. [PMID: 9469708 DOI: 10.1002/mrm.1910390212] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Collagen-rich tissues such as skin or fibrous cartilage have very short T2 and thus, in order to be visible, demand a commensurate reduction in echo time. Whereas short echo time for imaging of humans is straightforward at large fields of view with currently available whole body gradient hardware, the problem is more challenging in the microscopic resolution regime (<100 microm). In this work a simple approach consisting of shortening the echo time dynamically toward the lower spatial frequencies is described for three-dimensional partial flip-angle gradient and spin-echo sequences. Microimages obtained in vivo at 50 microm resolution on a 1.5 T whole body scanner are shown to afford a signal-to-noise gain of over 100% in the dermis of the human skin. A point-spread function analysis indicates that the variable echo time gradient-echo sequence produces a unique not previously reported off-resonance artifact in the phase-encoding direction. The artifact results from the phase modulation occurring during the variable echo time and can manifest as both blurring and intensity fluctuations, as well as shifts of boundaries in the phase-encoding direction. However, for the on-resonance condition, the images are free from these artifacts and exhibit significantly improved signal-to-noise ratio.
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Affiliation(s)
- H K Song
- Department of Radiology, University of Pennsylvania Medical Center, Philadelphia 19104, USA
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41
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Affiliation(s)
- D Rudikoff
- Department of Dermatology, Mount Sinai Medical Center, New York, New York 10029-6574, USA
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42
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Gniadecka M. Potential for high-frequency ultrasonography, nuclear magnetic resonance, and Raman spectroscopy for skin studies. Skin Res Technol 1997; 3:139-46. [DOI: 10.1111/j.1600-0846.1997.tb00178.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
The requirements for imaging the skin are dictated by the organ's layered structure, which extends only a few millimeters from the surface and thus demands extremely high resolution in this direction. While less critical, resolution in the remaining two dimensions determines whether the skin's accessory structures can be resolved. The problem is compounded by short transverse relaxation times, in particular of the dermis, the structure of most clinical interest. In this work images of the normal human skin were obtained in vivo at voxel sizes as small as 19 x 78 x 800 microm3, by means of customized 3D gradient and partial flip-angle spin-echo pulse sequences and very small transmit/receive coils on a 1.5T clinical imager equipped with high-power whole-body gradients. Structures resolved include hair follicles and the sublayers of the dermis. The very short time constant for the major component (91%) for transverse relaxation in the dermis (T2* approximately 10 ms) suggests the potential of substantial gains in achievable signal-to-noise ratio by shortening the echo time.
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Affiliation(s)
- H K Song
- Department of Radiology, University of Pennsylvania Medical Center, Philadelphia 19104, USA
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44
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Querleux B, Bittoun J. Measurement of epidermal moisture content. Br J Dermatol 1996. [DOI: 10.1111/j.1365-2133.1996.tb03628.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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45
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Ablett S, Burdett NG, Carpenter TA, Hall LD, Salter DC. Short echo time MRI enables visualisation of the natural state of human stratum corneum water in vivo. Magn Reson Imaging 1996; 14:357-60. [PMID: 8782172 DOI: 10.1016/0730-725x(95)02105-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
High resolution magnetic resonance imaging studies on skin have been limited by their inability to detect the low-moisture-content outer layers near the surface of the stratum corneum. The hydration of these outer layers is especially important physiologically. The present study shows that by using a short echo time of 5 ms it becomes possible to observe these layers in all but a few individuals with exceptionally dry skin. The quality of the images can be further improved by the use of separate transmit and receive coils, which reduces the rapid fall-off in signal intensity encountered with a single surface coil used both to transmit and receive.
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Affiliation(s)
- S Ablett
- Herchel Smith Laboratory for Medicinal Chemistry, University of Cambridge School for Clinical Medicine, UK
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46
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Affiliation(s)
- S Dikstein
- Unit of Cell Pharmacology, School of Pharmacy, Hebrew University, Jerusalem, Israel
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47
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Lodén M. Biophysical methods of providing objective documentation of the effects of moisturizing creams. Skin Res Technol 1995; 1:101-8. [DOI: 10.1111/j.1600-0846.1995.tb00028.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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48
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Gniadecka M. Non-invasive methods for determination of oedema and water behaviour in the skin. Skin Res Technol 1995; 1:55-60. [DOI: 10.1111/j.1600-0846.1995.tb00018.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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