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Zhong F, Wang F, Yang H. Composition and structure analysis of different depths in the stratum corneum using confocal Raman microscopy combined with two-dimensional correlation spectroscopy. Talanta 2024; 270:125559. [PMID: 38141465 DOI: 10.1016/j.talanta.2023.125559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 12/09/2023] [Accepted: 12/13/2023] [Indexed: 12/25/2023]
Abstract
The chemical composition and structure of the stratum corneum (SC) play a crucial role in the skin barrier function. Therefore, accurately determining the SC thickness and studying the changes in lipid and keratin structure and distribution within it are key aspects of skin barrier research. Currently, there are limited analytical tools and data analysis methods available for real-time and online studies of SC composition and structural changes. In this study, we focus on depth as a perturbation and employ confocal Raman microscopy combined with moving-window two-dimensional correlation spectroscopy (MW2D) technique to investigate the SC thickness. Additionally, we employ confocal Raman microscopy combined with perturbation-correlation moving-window two-dimensional correlation spectroscopy (PCMW2D) to precisely characterize the stratification of the SC. Furthermore, the two-dimensional correlation spectroscopy (2DCOS) method is utilized to examine the content of various conformations in the keratin secondary structure within the SC, as well as the subtle interrelationships between lipid and keratin structures.
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Affiliation(s)
- Feng Zhong
- The Education Ministry Key Lab of Resource Chemistry, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Municipal Education Committee Key Laboratory of Molecular Imaging Probes and Sensors, and Department of Chemistry, Shanghai Normal University, Shanghai, 200234, PR China
| | - Feng Wang
- The Education Ministry Key Lab of Resource Chemistry, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Municipal Education Committee Key Laboratory of Molecular Imaging Probes and Sensors, and Department of Chemistry, Shanghai Normal University, Shanghai, 200234, PR China.
| | - Haifeng Yang
- The Education Ministry Key Lab of Resource Chemistry, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Municipal Education Committee Key Laboratory of Molecular Imaging Probes and Sensors, and Department of Chemistry, Shanghai Normal University, Shanghai, 200234, PR China.
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2
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Banerjee A, Indoliya A, Poddar R. Edible oil based optical clearing for optical coherence tomography angiography imaging. Microvasc Res 2024; 154:104671. [PMID: 38460712 DOI: 10.1016/j.mvr.2024.104671] [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: 12/07/2023] [Revised: 02/19/2024] [Accepted: 03/04/2024] [Indexed: 03/11/2024]
Abstract
In optical imaging, optical clearing agents are commonly used to enhance the structural details of a sample. The current study investigates how to use it to improve the data obtained by an optical coherence tomography angiography system. A natural edible oil with no chemical base has been used for optical clearing. In-vivo testing on mice and humans yielded excellent optical clearing. Using computational techniques, the improvement in angiography signal caused by the optical clearing agent is investigated qualitatively and quantitatively. Compared to the control group, applying the edible oil-based optical clearing agent demonstrated improved vessel percentage and refined vascular signal intensity along depth.
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Affiliation(s)
- Abhishek Banerjee
- Biophotonics Lab, Department of Bioengineering, Birla Institute of Technology-Mesra, Ranchi, JH 835215, India
| | - Abhishek Indoliya
- Biophotonics Lab, Department of Bioengineering, Birla Institute of Technology-Mesra, Ranchi, JH 835215, India
| | - Raju Poddar
- Biophotonics Lab, Department of Bioengineering, Birla Institute of Technology-Mesra, Ranchi, JH 835215, India.
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3
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Douladiris N, Vakirlis E, Vassilopoulou E. Atopic Dermatitis and Water: Is There an Optimum Water Intake Level for Improving Atopic Skin? CHILDREN (BASEL, SWITZERLAND) 2023; 10:children10020273. [PMID: 36832402 PMCID: PMC9954916 DOI: 10.3390/children10020273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/20/2023] [Accepted: 01/29/2023] [Indexed: 02/04/2023]
Abstract
Water is a vital nutrient with innumerable functions for every living cell. The functions of human skin include protection against dehydration of the body. Atopic dermatitis (AD) is a chronic pruritic inflammatory skin disease that presents with dry skin, erythematous and eczematous lesions, and lichenification. This paper discusses the question of whether extra water intake in children with AD affects skin hydration and the skin barrier function. Among the methods used to treat dry skin, topical leave-on products are the first-line treatment, intended to improve hydration and the skin barrier function. The effectiveness of adequate water intake as a measure to treat dry skin is still under debate. Normal skin hydration increases with dietary water intake, particularly in those with prior lower water consumption. Skin dryness in AD is instrumental to the itch and inflammation cycle, contributing to barrier impairment and aggravating disease severity and flares. Certain emollients provide significant hydration to AD skin, with relief of dryness and reduction in barrier impairment, disease severity, and flares. Further investigations are needed to evaluate the optimum water intake levels in children with AD, as important questions remain unanswered, namely, does oral hydration provide relief of skin dryness and reduce barrier impairment, disease severity, and flares; is there any additional benefit from using mineral or thermal spring water; or is there a need to specifically study the fluid/water intake in children with AD and food allergy (FA) restrictions?
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Affiliation(s)
- Nikolaos Douladiris
- Allergy Unit, 2nd Pediatric Clinic, University of Athens, 11527 Athens, Greece
- Correspondence:
| | - Efstratios Vakirlis
- First Department of Dermatology and Venereology, School of Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Emilia Vassilopoulou
- Department of Nutritional Sciences and Dietetics, International Hellenic University, 57400 Thessaloniki, Greece
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4
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Jaafar A, Darvin ME, Tuchin VV, Veres M. Confocal Raman Micro-Spectroscopy for Discrimination of Glycerol Diffusivity in Ex Vivo Porcine Dura Mater. LIFE (BASEL, SWITZERLAND) 2022; 12:life12101534. [PMID: 36294969 PMCID: PMC9605590 DOI: 10.3390/life12101534] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 08/27/2022] [Accepted: 09/26/2022] [Indexed: 11/16/2022]
Abstract
Dura mater (DM) is a connective tissue with dense collagen, which is a protective membrane surrounding the human brain. The optical clearing (OC) method was used to make DM more transparent, thereby allowing to increase in-depth investigation by confocal Raman micro-spectroscopy and estimate the diffusivity of 50% glycerol and water migration. Glycerol concentration was obtained, and the diffusion coefficient was calculated, which ranged from 9.6 × 10-6 to 3.0 × 10-5 cm2/s. Collagen-related Raman band intensities were significantly increased for all depths from 50 to 200 µm after treatment. In addition, the changes in water content during OC showed that 50% glycerol induces tissue dehydration. Weakly and strongly bound water types were found to be most concentrated, playing a major role in the glycerol-induced water flux and OC. Results show that OC is an efficient method for controlling the DM optical properties, thereby enhancing the in-depth probing for laser therapy and diagnostics of the brain. DM is a comparable to various collagen-containing tissues and organs, such as sclera of eyes and skin dermis.
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Affiliation(s)
- Ali Jaafar
- Institute for Solid State Physics and Optics, Wigner Research Center for Physics, H-1525 Budapest, Hungary
- Institute of Physics, University of Szeged, Dom ter 9, H-6720 Szeged, Hungary
- Ministry of Higher Education and Scientific Research, Baghdad 10065, Iraq
- Correspondence:
| | - Maxim E. Darvin
- Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Venerology and Allergology, Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Valery V. Tuchin
- Science Medical Center, Saratov State University, 83 Astrakhanskaya Str., 410012 Saratov, Russia
- Laboratory of Laser Diagnostics of Technical and Living Systems, Institute of Precision Mechanics and Control, FRC “Saratov Scientific Centre of the Russian Academy of Sciences”, 24 Rabochaya Str., 410028 Saratov, Russia
- A.N. Bach Institute of Biochemistry, FRC “Biotechnology of the Russian Academy of Sciences”, 33-2 Leninsky Prospect, 119071 Moscow, Russia
| | - Miklós Veres
- Institute for Solid State Physics and Optics, Wigner Research Center for Physics, H-1525 Budapest, Hungary
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5
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Rigal A, Michael-Jubeli R, Nkengne A, Baillet-Guffroy A, Bigouret A, Tfayli A. Raman confocal microscopy and biophysics multiparametric characterization of the skin barrier evolution with age. JOURNAL OF BIOPHOTONICS 2021; 14:e202100107. [PMID: 34105894 DOI: 10.1002/jbio.202100107] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 06/01/2021] [Accepted: 06/02/2021] [Indexed: 06/12/2023]
Abstract
Skin aging is a multifactorial phenomenon that involves alterations at the molecular, cellular and tissue levels. Our aim was to carry out a multiparametric biophysical and Raman characterization of skin barrier between individuals of different age groups (<24 and >70 years old). Our results showed a significant decrease of lipids to proteins ratio overall the thickness of the stratum corneum and higher lateral packing in the outer part of the SC for elderly. This can explain the decrease in trans epidermal water loss measured values rather than only SC thickening. Both age groups showed similar water content at SC surface while elderly presented higher water content in deep SC and viable epidermis. Mechanical measurements showed a decrease in the elasticity and an increase in the fatigability with age and were correlated with partially bound water. Highest correlation and anti-correlation values were observed for the deepest part of the SC and the viable epidermis.
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Affiliation(s)
- Aline Rigal
- Lipides: Systèmes Analytiques et Biologiques Lip(Sys)2 Interdisciplinary Unit, Faculty of Pharmacy, University Paris-Saclay, Châtenay-Malabry, France
| | - Rime Michael-Jubeli
- Lipides: Systèmes Analytiques et Biologiques Lip(Sys)2 Interdisciplinary Unit, Faculty of Pharmacy, University Paris-Saclay, Châtenay-Malabry, France
| | - Alex Nkengne
- Clarins Laboratories, LEC : Laboratoire d'Evaluation Clinique, Pontoise, France
| | - Arlette Baillet-Guffroy
- Lipides: Systèmes Analytiques et Biologiques Lip(Sys)2 Interdisciplinary Unit, Faculty of Pharmacy, University Paris-Saclay, Châtenay-Malabry, France
| | - Armelle Bigouret
- Clarins Laboratories, LEC : Laboratoire d'Evaluation Clinique, Pontoise, France
| | - Ali Tfayli
- Lipides: Systèmes Analytiques et Biologiques Lip(Sys)2 Interdisciplinary Unit, Faculty of Pharmacy, University Paris-Saclay, Châtenay-Malabry, France
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6
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Li D, Zhu Z, Sun DW. Visualization of the in situ distribution of contents and hydrogen bonding states of cellular level water in apple tissues by confocal Raman microscopy. Analyst 2020; 145:897-907. [PMID: 31820748 DOI: 10.1039/c9an01743g] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Raman spectroscopy has been employed for studying the hydrogen bonding states of water molecules for decades, however, Raman imaging data contain thousands of spectra, making it challenging to obtain information on water with different hydrogen bonds. In the current study, a novel method combining confocal Raman microscopy (CRM) imaging with the iterative curve fitting algorithms was developed to determine the distribution of water contents at the cellular level and water states with different hydrogen bonds in apple tissues. Raman imaging data ranging from 2700 to 3800 cm-1 were acquired from whole cells in the apple tissue, which were then decomposed into seven sub-peaks using the fixed-position Gaussian iterative curve fitting (FPGICF) algorithm. The content and hydrogen bonding states of cellular water were calculated as the area sum of the OH stretching vibration and the area ratio of DA-OH over DDAA-OH stretching vibration or the number of hydrogen bonds of each water molecule, respectively. Finally, the area of each sub-peak, the area sum of the OH stretching vibration, and the area ratio of DA-OH over DDAA-OH stretching vibration were used to visualize the distribution of each sub-peak, water contents and water states with different hydrogen bonds, respectively. In addition, it was found that the number of hydrogen bonds of each water molecule could also be considered as a criterion to describe the hydrogen bond states of water in apple tissues. The availability of such information should provide new insights for future study of cellular water in other food materials.
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Affiliation(s)
- Dongmei Li
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China.
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Zhang W, Ma J, Sun DW. Raman spectroscopic techniques for detecting structure and quality of frozen foods: principles and applications. Crit Rev Food Sci Nutr 2020; 61:2623-2639. [DOI: 10.1080/10408398.2020.1828814] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Wenyang Zhang
- School of Food Science and Engineering, South China University of Technology, Guangzhou, China
- Academy of Contemporary Food Engineering, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, China
- Engineering and Technological Research Centre of Guangdong Province on Intelligent Sensing and Process Control of Cold Chain Foods, & Guangdong Province Engineering Laboratory for Intelligent Cold Chain Logistics Equipment for Agricultural Products, Guangzhou Higher Education Mega Centre, Guangzhou, China
| | - Ji Ma
- School of Food Science and Engineering, South China University of Technology, Guangzhou, China
- Academy of Contemporary Food Engineering, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, China
- Engineering and Technological Research Centre of Guangdong Province on Intelligent Sensing and Process Control of Cold Chain Foods, & Guangdong Province Engineering Laboratory for Intelligent Cold Chain Logistics Equipment for Agricultural Products, Guangzhou Higher Education Mega Centre, Guangzhou, China
- State Key Laboratory of Luminescent Materials and Devices, Center for Aggregation-Induced Emission, South China University of Technology, Guangzhou, China
| | - Da-Wen Sun
- School of Food Science and Engineering, South China University of Technology, Guangzhou, China
- Academy of Contemporary Food Engineering, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, China
- Engineering and Technological Research Centre of Guangdong Province on Intelligent Sensing and Process Control of Cold Chain Foods, & Guangdong Province Engineering Laboratory for Intelligent Cold Chain Logistics Equipment for Agricultural Products, Guangzhou Higher Education Mega Centre, Guangzhou, China
- Food Refrigeration and Computerized Food Technology (FRCFT), Agriculture and Food Science Centre, University College Dublin, National University of Ireland, Dublin 4, Ireland
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Choe C, Schleusener J, Choe S, Ri J, Lademann J, Darvin ME. Stratum corneum occlusion induces water transformation towards lower bonding state: a molecular level in vivo study by confocal Raman microspectroscopy. Int J Cosmet Sci 2020; 42:482-493. [PMID: 32692411 DOI: 10.1111/ics.12653] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/15/2020] [Accepted: 07/17/2020] [Indexed: 12/23/2022]
Abstract
OBJECTIVE It is conventionally understood that occlusive effects are the retention of excessive water in the stratum corneum (SC), the increase of SC thickness (swelling) and a decrease of the transepidermal water loss. However, the influence of occlusion on water binding properties in the SC is unknown. METHODS The action of plant-derived jojoba and almond oils, as well as mineral-derived paraffin oil and petrolatum topically applied on human skin, is investigated in vivo using confocal Raman microspectroscopy. To understand the oils' influence on the SC on the molecular level, the depth-dependent hydrogen bonding states of water in the SC and their relationship to the conformation of keratin, concentration of natural moisturizing factor (NMF) molecules and lipid organization were investigated. RESULTS A significant SC swelling was observed only in petrolatum-treated skin. The water concentration was increased in oil-treated skin in the intermediate SC region (40-70% SC depth). Meanwhile, the amount of free, weakly and tightly bound water increased, and strongly bound water decreased in the uppermost SC region (0-30% SC depth). The NMF concentration of oil-treated skin was significantly lower at 50-70% SC depth. The lateral organization of lipids in oil-treated skin was lower at 0-30% SC depth. The secondary structure of keratin was changed towards an increase of β-sheet content in mineral-derived oil-treated skin and changed towards an increase of α-helix content in plant-derived oil-treated skin. CONCLUSION The occlusive properties can be summarized as the increase of free water and the transformation of water from a more strongly to a more weakly hydrogen bonding state in the uppermost SC, although some oils cause insignificant changes of the SC thickness. The accompanied changes in the keratin conformation at the intermediate swelling region of the SC also emphasize the role of keratin in the SC's water-transporting system, that is the water in the SC transports intercellularly and intracellularly in the intermediate swelling region and only intercellularly in the uppermost non-swelling region. Bearing this in mind, almond, jojoba and paraffin oils, which are not occlusive from the conventional viewpoint, have an occlusion effect similar to petrolatum on the SC.
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Affiliation(s)
- C Choe
- Kim Il Sung University, Taesong District, Ryongnam-Dong, Pyongyang, DPR Korea
| | - J Schleusener
- Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Charitéplatz 1, Berlin, 10117, Germany
| | - S Choe
- Kim Il Sung University, Taesong District, Ryongnam-Dong, Pyongyang, DPR Korea
| | - J Ri
- Kim Il Sung University, Taesong District, Ryongnam-Dong, Pyongyang, DPR Korea
| | - J Lademann
- Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Charitéplatz 1, Berlin, 10117, Germany
| | - M E Darvin
- Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Charitéplatz 1, Berlin, 10117, Germany
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9
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Maruyama Y, Kamata H, Watanabe S, Kita R, Shinyashiki N, Yagihara S. Electric-field penetration depth and dielectric spectroscopy observations of human skin. Skin Res Technol 2019; 26:255-262. [PMID: 31556189 PMCID: PMC7079190 DOI: 10.1111/srt.12788] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 09/02/2019] [Indexed: 12/02/2022]
Abstract
Background The dynamic behavior of water molecules remains an important subject for understanding human skin. The change in the dynamics of water molecules from those in bulk water can be effectively observed by dielectric spectroscopy. To study water in the human skin in vivo, non‐invasive and non‐destructive measurements are essential. Since many unknowns remain from previous research, in this report we employ a two‐layer dielectric model to evaluate the penetration depth of the electric field and use the results in measurements on human skin. Materials and Methods We used open‐ended coaxial probes with different diameters to perform time‐domain reflectometry (TDR) measurements for an acetone‐Teflon double‐layer model and for human skin from various parts of the body. Results The electric‐field penetration depth obtained from model measurements increases with the increasing outer diameter of open‐ended coaxial electrodes. For skin measurements, the relaxation strength corresponding to the water content shows a clear dependence on the epidermal thickness of the measured body parts. Conclusion We determined the depth distribution of the water content of skin from results of dielectric measurements obtained using electrodes with various electric‐field penetration depths. We found exponential decays with the thickness of the epidermis of each body part for several examinees. This study suggests an effective method for detailed evaluations of human skin.
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Affiliation(s)
- Yuko Maruyama
- Graduate School of Science and Technology, Tokai University, Hiratsuka, Kanagawa, Japan
| | - Hayato Kamata
- Graduate School of Science, Tokai University, Hiratsuka, Kanagawa, Japan
| | - Seiei Watanabe
- Graduate School of Science, Tokai University, Hiratsuka, Kanagawa, Japan
| | - Rio Kita
- Department of Physics, School of Science, Tokai University, Hiratsuka, Kanagawa, Japan
| | - Naoki Shinyashiki
- Department of Physics, School of Science, Tokai University, Hiratsuka, Kanagawa, Japan
| | - Shin Yagihara
- Department of Physics, School of Science, Tokai University, Hiratsuka, Kanagawa, Japan
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10
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Sdobnov AY, Darvin ME, Schleusener J, Lademann J, Tuchin VV. Hydrogen bound water profiles in the skin influenced by optical clearing molecular agents-Quantitative analysis using confocal Raman microscopy. JOURNAL OF BIOPHOTONICS 2019; 12:e201800283. [PMID: 30565427 DOI: 10.1002/jbio.201800283] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 12/14/2018] [Accepted: 12/17/2018] [Indexed: 05/21/2023]
Abstract
Confocal Raman microscopy has been used to measure depth-dependent profiles of porcine skin ex vivo in the high wavenumber region after application of molecular optical clearing agents (OCAs). Glycerol (70%) and iohexol (100% Omnipaque [300]) water solutions were used as OCAs and topically applied to porcine ear skin for 30 and 60 minutes. Using Gaussian function-based deconvolution, the changes of hydrogen bound water molecule types have been microscopically analyzed down to the depth of 200 μm. Results show that both OCAs induced skin dehydration (reduction of total water), which is 51.3% for glycerol (60 minutes), 33.1% for glycerol (30 minutes), 8.3% for Omnipaque (60 minutes) and 4.4% for Omnipaque (30 minutes), on average for the 40 to 200 μm depths. Among the water types in the skin, the following reduction was observed in concentration of weakly bound (51.1%, 33.2%, 7.5% and 4.6%), strongly bound (50.4%, 33.0%, 7.9% and 3.4%), tightly bound (63.6%, 42.3%, 26.1% and 12.9%) and unbound (55.4%, 28.7%, 10.1% and 5.9%) water types on average for the 40 to 200 μm depths, post application of glycerol (60 minutes), glycerol (30 minutes), Omnipaque (60 minutes) and Omnipaque (30 minutes), respectively. As most concentrated in the skin, weakly and strongly bound water types are preferentially involved in the OCA-induced water flux in the skin, and thus, are responsible for optical clearing efficiency.
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Affiliation(s)
- Anton Y Sdobnov
- Faculty of Information Technology and Electrical Engineering, University of Oulu, Oulu, Finland
- Department of Optics and Biophotonics, Research-Educational Institute of Optics and Biophotonics, Saratov State University, Saratov, Russia
| | - Maxim E Darvin
- Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
| | - Johannes Schleusener
- Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
| | - Jürgen Lademann
- Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
| | - Valery V Tuchin
- Department of Optics and Biophotonics, Research-Educational Institute of Optics and Biophotonics, Saratov State University, Saratov, Russia
- Laboratory of Laser Diagnostics of Technical and Living Systems, Institute of Precision Mechanics and Control of RAS, Saratov, Russia
- Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk, Russia
- Laboratory of Molecular Imaging, Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
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11
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Bielfeldt S, Springmann G, Seise M, Wilhelm KP, Callaghan T. An updated review of clinical methods in the assessment of ageing skin - New perspectives and evaluation for claims support. Int J Cosmet Sci 2018; 40:348-355. [PMID: 30047989 DOI: 10.1111/ics.12484] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 07/23/2018] [Indexed: 12/11/2022]
Abstract
With the advancement of skin research, today's consumer has increased access to an informed understanding of ageing skin and its appendages, together with a plethora of targeted products to meet such needs. In recent years, increased legislative demands for quality evidential claims support have led not only to the development and validation of clinical methods to measure and quantify ageing skin, but also a clearer understanding of the skin ageing process-especially the impact of both its internal and external environments-as well as a tougher stance on clearly unjustifiable claims. Traditional testing methods used to research and evaluate anti-ageing products claim to employ sophisticated instruments. Today, however, since the term anti-ageing can be considered a misnomer, intelligent use of combined more advanced clinical methods has enabled the development of technologically improved consumer products providing enhanced efficacy and targeted performance. Non-invasive methods for the assessment and quantification of the causes of ageing skin provide tools to the clinical researcher as defined by key clinically observed ageing parameters. Where evidence requires additional support, a number of clinical procedures evaluating ageing skin and hair products are combined with invasive procedures, thus enabling an added value to product claims. As discussed herein, given the enhanced understanding of ageing, we provide an update to our previous reviews of clinical methods used in the assessment of skin ageing, to include the wider aspects of environmental exposure; skin pigmentation; microbiome disturbance; surface topography; colour, radiance, and pH; and structural integrity-all requiring a disciplined approach to their use in dermatological investigations and product claims evidence.
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Affiliation(s)
- S Bielfeldt
- proDERM Institute for Applied Dermatological Research, 22869, Schenefeld/Hamburg, Germany
| | - G Springmann
- proDERM Institute for Applied Dermatological Research, 22869, Schenefeld/Hamburg, Germany
| | - M Seise
- proDERM Institute for Applied Dermatological Research, 22869, Schenefeld/Hamburg, Germany
| | - K-P Wilhelm
- proDERM Institute for Applied Dermatological Research, 22869, Schenefeld/Hamburg, Germany
| | - T Callaghan
- Callaghan Consulting International, 22587, Hamburg, Germany
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12
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Kerch G. Distribution of tightly and loosely bound water in biological macromolecules and age-related diseases. Int J Biol Macromol 2018; 118:1310-1318. [PMID: 29981332 DOI: 10.1016/j.ijbiomac.2018.06.187] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 05/21/2018] [Accepted: 06/29/2018] [Indexed: 02/06/2023]
Abstract
This mini-review article is focused on publications devoted to the changes in water binding energy and content of bound water in biological tissues during aging processes, when bound water lost from the hydration layer becomes free water. Bound water is released during cataractogenesis. In skin, water bound to proteins and other biomacromolecules becomes more mobile with increasing skin age. Extracellular to intracellular water ratio increases with age and was associated with muscle cell atrophy. Bound water concentration decreases with age in hydrated human bone and can be correlated with the strength and toughness of the bone. Higher fraction of free water in malignant tissues compared to normal tissues was observed. Hydration water mobility is enhanced around tau amyloid fibers. Water plays a decisive role in amyloid formation as entropic driving force. In the natural aging processes dehydration and glycation may be considered as subsequent steps.
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Affiliation(s)
- G Kerch
- Institute of Polymer Materials, Department of Materials Science and Applied Chemistry, Riga Technical University, Azenes 14/24, Riga, Latvia.
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13
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Age related depth profiles of human Stratum Corneum barrier-related molecular parameters by confocal Raman microscopy in vivo. Mech Ageing Dev 2018; 172:6-12. [DOI: 10.1016/j.mad.2017.08.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 08/19/2017] [Indexed: 12/20/2022]
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Choe C, Schleusener J, Lademann J, Darvin ME. Human skin in vivo has a higher skin barrier function than porcine skin ex vivo-comprehensive Raman microscopic study of the stratum corneum. JOURNAL OF BIOPHOTONICS 2018; 11:e201700355. [PMID: 29460347 DOI: 10.1002/jbio.201700355] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 02/18/2018] [Indexed: 06/08/2023]
Abstract
Porcine skin is widely used as a human skin model in dermatology. For both, porcine stratum corneum (SC) ex vivo and human SC in vivo, the hydrogen bonding states of water, the secondary and tertiary structures of keratin, the natural moisturizing factor (NMF) concentrations and the intercellular lipids' (ICL) lateral organization are investigated depth-dependently using confocal Raman microscopy. The SC depth profiles show that porcine SC ex vivo is characterized by lower hydrogen bonding states of water (10%-30% SC depth), lower NMF concentration in the whole SC, more β-sheet form of keratin (10%-90% SC depth), more folded tertiary keratin structures (30%-70% SC depth) and higher hexagonal lateral packing order of ICL (10%-50% SC depth) compared to human SC in vivo. The results clearly show a higher value of skin barrier function of human SC in vivo than of porcine SC ex vivo. Thus, the human SC in vivo is less permeable for lipophilic and hydrophilic substances than porcine SC ex vivo. Considering the porcine SC as an ex vivo model of human SC in vivo, these findings should be taken into consideration.
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Affiliation(s)
- ChunSik Choe
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117 Berlin, Germany
- Kim Il Sung University, Ryongnam-Dong, Taesong District, Pyongyang, DPR Korea
| | - Johannes Schleusener
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117 Berlin, Germany
| | - Jürgen Lademann
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117 Berlin, Germany
| | - Maxim E Darvin
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117 Berlin, Germany
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15
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Akdeniz M, Tomova‐Simitchieva T, Dobos G, Blume‐Peytavi U, Kottner J. Does dietary fluid intake affect skin hydration in healthy humans? A systematic literature review. Skin Res Technol 2018; 24:459-465. [DOI: 10.1111/srt.12454] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/01/2018] [Indexed: 11/27/2022]
Affiliation(s)
- M. Akdeniz
- Department of Dermatology and AllergyClinical Research Center for Hair and Skin ScienceCharité—Universitätsmedizin Berlin Berlin Germany
| | - T. Tomova‐Simitchieva
- Department of Dermatology and AllergyClinical Research Center for Hair and Skin ScienceCharité—Universitätsmedizin Berlin Berlin Germany
| | - G. Dobos
- Department of Dermatology and AllergyClinical Research Center for Hair and Skin ScienceCharité—Universitätsmedizin Berlin Berlin Germany
| | - U. Blume‐Peytavi
- Department of Dermatology and AllergyClinical Research Center for Hair and Skin ScienceCharité—Universitätsmedizin Berlin Berlin Germany
| | - J. Kottner
- Department of Dermatology and AllergyClinical Research Center for Hair and Skin ScienceCharité—Universitätsmedizin Berlin Berlin Germany
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Choe C, Schleusener J, Lademann J, Darvin ME. Keratin-water-NMF interaction as a three layer model in the human stratum corneum using in vivo confocal Raman microscopy. Sci Rep 2017; 7:15900. [PMID: 29162917 PMCID: PMC5698327 DOI: 10.1038/s41598-017-16202-x] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 11/09/2017] [Indexed: 11/09/2022] Open
Abstract
The secondary and tertiary structure of keratin and natural moisturizing factor (NMF) are of great importance regarding the water regulating functions in the stratum corneum (SC). In this in vivo study, the depth-dependent keratin conformation and its relationship to the hydrogen bonding states of water and its content in the SC, are investigated using confocal Raman microscopy. Based on the obtained depth-profiles for the β-sheet/α-helix ratio, the stability of disulphide bonds, the amount of cysteine forming disulphide bonds, the buried/exposed tyrosine and the folding/unfolding states of keratin, a "three layer model" of the SC, regarding the keratin-water-NMF interaction is proposed. At the uppermost layers (30-0% SC depth), the keratin filaments are highly folded, entailing limited water binding sites, and NMF is mostly responsible for binding water. At the intermediate layers (70-30% SC depth), the keratin filaments are unfolded, have the most water binding sites and are prone to swelling. At the bottom layers (100-80% SC depth), the water binding sites are already occupied with water and cannot swell substantially. The hydrogen bonding states of water molecules can only be explained by considering both, the molecular structure of keratin and the contribution of NMF as a holistic system.
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Affiliation(s)
- ChunSik Choe
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117, Berlin, Germany.,Kim Il Sung University, Ryongnam-Dong, Taesong District, Pyongyang, Democratic People's Republic of Korea
| | - Johannes Schleusener
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117, Berlin, Germany
| | - Jürgen Lademann
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117, Berlin, Germany
| | - Maxim E Darvin
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117, Berlin, Germany.
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17
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Choe C, Lademann J, Darvin ME. A depth-dependent profile of the lipid conformation and lateral packing order of the stratum corneum in vivo measured using Raman microscopy. Analyst 2017; 141:1981-7. [PMID: 26855232 DOI: 10.1039/c5an02373d] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The intercellular lipid structure of the stratum corneum (SC) plays a key role in skin barrier function. A depth profile of the intercellular lipid conformation and the lipid lateral packing order were measured in vivo in the human SC using confocal Raman microscopy. The depth profiles of the 2880 cm(-1)/2850 cm(-1) peak ratio intensity, which represent the C-H stretching and lateral packing order of lipids, and the 1080 cm(-1)/(1130 cm(-1) + 1060 cm(-1)) peak ratio, which represents the C-C skeleton vibration and trans-gauche conformation order of lipids, were investigated. The influence of keratin on the lipid peaks at 2850 cm(-1) and 2880 cm(-1) was excluded by the developed mathematical algorithm. The results show that the trans-conformation and lateral packing order of the intercellular lipids reach their maximum value in the SC at 20-40% of its depth and then decrease towards the stratum granulosum. These results show that at a depth of 20-40% (normally corresponding to a depth of 4-8 μm) the SC exhibits the most ordered lipids and therefore the highest skin barrier function. The lateral packing of lipids is more disordered on the surface and in the deeper parts of the SC, which may be associated with a reduced skin barrier function.
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Affiliation(s)
- ChunSik Choe
- Charité - Universitätsmedizin Berlin, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117 Berlin, Germany. and Kim Il Sung University, Ryongnam-Dong, Taesong District, Pyongyang, DPR Korea
| | - Jürgen Lademann
- Charité - Universitätsmedizin Berlin, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117 Berlin, Germany.
| | - Maxim E Darvin
- Charité - Universitätsmedizin Berlin, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117 Berlin, Germany.
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18
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Choe C, Lademann J, Darvin ME. Depth profiles of hydrogen bound water molecule types and their relation to lipid and protein interaction in the human stratum corneum in vivo. Analyst 2016; 141:6329-6337. [PMID: 27774531 DOI: 10.1039/c6an01717g] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Confocal Raman microscopy has been used to measure depth-dependent profiles of human SC in vivo in the high wavenumber (HWN) region. In order to keep the linearity of HWN region boundaries and to not remove an informative signal from Raman spectra, a new baseline subtraction procedure has been introduced. After baseline subtraction, the HWN spectrum was deconvoluted using 10 Gaussian functions with individual chemical meanings. The results show that the hydrogen bound water molecule types contributed differently to the water diffusion process in the SC. The most concentrated double donor-double acceptor (DDAA) and single donor-single acceptor (DA) water molecule types in the SC represent more than 90% of the SC's water and mostly contribute to the water flux in the skin. Single donor-double acceptor (DAA) and weakly-bound water molecule types represent less than 10% of the SC's water content. The most tightly hydrogen bound water molecule type, DAA, reaches its maximum concentration near the skin surface and does not take part in the water diffusion process via the SC. The results show that the hydrogen bonding state of water (DA/DDAA water molecule type ratio) reaches its maximum at the depth of approx. 30% of the SC thickness, which correlates well with the maximum lateral packing order of intercellular lipids (ICL) and the natural moisturizing factor (NMF), and does not coincide with the folding/unfolding state of keratin. The NMF's contribution to the bonding of water in the SC is supposed to dominate over that of ICL.
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Affiliation(s)
- ChunSik Choe
- Charité- Universitätsmedizin Berlin, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117 Berlin, Germany.
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Wohlrab J, Richter C, Stauder S. Präklinische und klinische Validierung der kutanen Bioverfügbarkeit der hydrophilen Phase einer W/O-Emulsion. J Dtsch Dermatol Ges 2016. [DOI: 10.1111/ddg.12732_g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Johannes Wohlrab
- Universitätsklinik und Poliklinik für Dermatologie und Venerologie; Martin-Luther-Universität Halle-Wittenberg; Halle (Saale)
- Institut für angewandte Dermatopharmazie; Martin-Luther-Universität Halle-Wittenberg; Halle (Saale)
| | - Claudia Richter
- Klinik für Dermatologie; Venerologie und Allergologie; Charité Universitätsmedizin Berlin; Berlin
| | - Susanne Stauder
- Universitätsklinik und Poliklinik für Dermatologie und Venerologie; Martin-Luther-Universität Halle-Wittenberg; Halle (Saale)
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20
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Wohlrab J, Richter C, Stauder S. Preclinical and clinical characterization of the cutaneous bioavailability of the hydrophilic phase of a water-in-oil emulsion. J Dtsch Dermatol Ges 2015; 14:698-705. [PMID: 26636922 DOI: 10.1111/ddg.12732] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Interactions between the stratum corneum and individual phases of an emulsion system depend on various factors, but primarily on the outer continuous phase of the system. While there is plenty of data on the lipophilic phase, only very little data exists on the actual penetration of the hydrophilic phase of water-in-oil emulsions into the stratum corneum. PATIENTS AND METHODS Against this background, two comparable water-in-oil emulsions were preclinically and clinically investigated on healthy as well as on artificially damaged skin with regard to interactions of the hydrophilic phase. In preclinical studies, following epicutaneous application on ex vivo skin, the distribution of the hydrophilic phase was quantified using fluorescence tests and analyzed according to anatomic layers. Additionally, a randomized, controlled, investigator-blinded study investigated the effects of the preparations on the barrier function of healthy and artificially damaged skin over time. RESULTS The results clearly show that water substitution using a water-in-oil emulsion can only partially be attained by the addition of hygroscopic substances (e. g. urea). These effects may primarily be explained by the occlusive properties of the lipophilic phase. CONCLUSIONS This, the use of water-in-oil emulsions may in particular be recommended for chronic barrier impairment, as long-lasting effects are not to be expected in acutely damaged skin.
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Affiliation(s)
- Johannes Wohlrab
- Department of Dermatology and Venereology, Martin-Luther -University Halle-Wittenberg, Halle (Saale), Germany.,Institute of Applied Dermatopharmacy, Martin-Luther -University -Halle-Wittenberg, Halle (Saale), Germany
| | - Claudia Richter
- Department of Dermatology, -Venereology and Allergology, Charité University Medicine Berlin, Berlin, Germany
| | - Susanne Stauder
- Department of Dermatology and Venereology, Martin-Luther -University Halle-Wittenberg, Halle (Saale), Germany
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Mayrovitz HN, Grammenos A, Corbitt K, Bartos S. Age-related changes in male forearm skin-to-fat tissue dielectric constant at 300 MHz. Clin Physiol Funct Imaging 2015; 37:198-204. [PMID: 26278683 DOI: 10.1111/cpf.12286] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Accepted: 06/29/2015] [Indexed: 11/29/2022]
Abstract
Prior research suggests that tissue dielectric constant (TDC) values are useful to assess localized skin water in females for early diagnosing breast cancer treatment-related lymphoedema and TDC values in young adults have shown gender differences. However, no TDC data are available for older males nor have ageing effects been studied despite known shifts in water state and other skin age-related changes. Thus our goals were to (i) characterize TDC values at various skin depths in young and older males, (ii) determine the dependence of these values on body composition parameters and (iii) establish inter-arm TDC ratios for use as normal male reference values. TDC measurements were made to depths of 0·5, 1·5, 2·5 and 5·0 mm bilaterally on volar forearm skin in 60 males in three groups of 20 that had mean ages ± SD of 24·0 ± 0·9, 40·0 ± 12·9 and 71·0 ± 8·0 years. Total body fat and water percentages were determined via bioimpedance at 50 KHz. Results showed that (i) for all age groups TDC values decreased with increasing depth, (ii) TDC values were not statistically different among age groups except at a depth of 0·5 mm, (iii) TDC values were highly negatively correlated with total body fat and (iv) inter-arm ratios varied little among age groups and depths. It is concluded that (i) age-related larger TDC values at only the shallowest depth is consistent with skin water shifting state from bound to more mobile in the oldest group and (ii) inter-arm ratios at any depth provide a basis to test for unilateral oedema.
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Affiliation(s)
- Harvey N Mayrovitz
- College of Medical Sciences, Nova Southeastern University, Ft. Lauderdale, FL, USA
| | - Alexandra Grammenos
- College of Medical Sciences, Nova Southeastern University, Ft. Lauderdale, FL, USA
| | - Kelly Corbitt
- College of Medical Sciences, Nova Southeastern University, Ft. Lauderdale, FL, USA
| | - Simona Bartos
- College of Medical Sciences, Nova Southeastern University, Ft. Lauderdale, FL, USA
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22
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Mayrovitz HN, Singh A, Akolkar S. Age-related differences in tissue dielectric constant values of female forearm skin measured noninvasively at 300 MHz. Skin Res Technol 2015; 22:189-95. [DOI: 10.1111/srt.12249] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/17/2015] [Indexed: 11/30/2022]
Affiliation(s)
- H. N. Mayrovitz
- College of Medical Sciences; Nova Southeastern University; Ft. Lauderdale FL USA
| | - A. Singh
- College of Medical Sciences; Nova Southeastern University; Ft. Lauderdale FL USA
| | - S. Akolkar
- College of Medical Sciences; Nova Southeastern University; Ft. Lauderdale FL USA
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