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Witt NJ, Woessner AE, Herrmann J, Quinn KP, Sander EA. Mechanical Models of Collagen Networks for Understanding Changes in the Failure Properties of Aging Skin. J Biomech Eng 2024; 146:071002. [PMID: 38183223 PMCID: PMC10983714 DOI: 10.1115/1.4064406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 12/19/2023] [Accepted: 12/27/2023] [Indexed: 01/07/2024]
Abstract
Skin undergoes mechanical alterations due to changes in the composition and structure of the collagenous dermis with aging. Previous studies have conflicting findings, with both increased and decreased stiffness reported for aging skin. The underlying structure-function relationships that drive age-related changes are complex and difficult to study individually. One potential contributor to these variations is the accumulation of nonenzymatic crosslinks within collagen fibers, which affect dermal collagen remodeling and mechanical properties. Specifically, these crosslinks make individual fibers stiffer in their plastic loading region and lead to increased fragmentation of the collagenous network. To better understand the influence of these changes, we investigated the impact of nonenzymatic crosslink changes on the dermal microstructure using discrete fiber networks representative of the dermal microstructure. Our findings suggest that stiffening the plastic region of collagen's mechanical response has minimal effects on network-level stiffness and failure stresses. Conversely, simulating fragmentation through a loss of connectivity substantially reduces network stiffness and failure stress, while increasing stretch ratios at failure.
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Affiliation(s)
- Nathan J. Witt
- Roy J. Carver Department of Biomedical Engineering, College of Engineering, University of Iowa, Iowa City, IA 52240
| | - Alan E. Woessner
- Department of Biomedical Engineering, University of Arkansas, Fayetteville, AR 72701
| | - Jacob Herrmann
- Roy J. Carver Department of Biomedical Engineering, College of Engineering, University of Iowa, Iowa City, IA 52242
| | - Kyle P. Quinn
- Department of Biomedical Engineering, University of Arkansas, Fayetteville, AR 72701
| | - Edward A. Sander
- Roy J. Carver Department of Biomedical Engineering, College of Engineering, University of Iowa, 5629 Seamans Center, Iowa City, IA 52242; Department of Orthopedics and Rehabilitation, Carver College of Medicine, University of Iowa, Iowa City, IA 52242
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2
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Zhou M, González PJ, Van Haasterecht L, Soylu A, Mihailovski M, Van Zuijlen P, Groot ML. Uniaxial mechanical stretch properties correlated with three-dimensional microstructure of human dermal skin. Biomech Model Mechanobiol 2024; 23:911-925. [PMID: 38324073 PMCID: PMC11101527 DOI: 10.1007/s10237-023-01813-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 12/30/2023] [Indexed: 02/08/2024]
Abstract
The intact and healthy skin forms a barrier to the outside world and protects the body from mechanical impact. The skin is a complex structure with unique mechano-elastic properties. To better direct the design of biomimetic materials and induce skin regeneration in wounds with optimal outcome, more insight is required in how the mechano-elastic properties emerge from the skin's main constituents, collagen and elastin fibers. Here, we employed two-photon excited autofluorescence and second harmonic generation microscopy to characterize collagen and elastin fibers in 3D in 24 human dermis skin samples. Through uniaxial stretching experiments, we derive uni-directional mechanical properties from resultant stress-strain curves, including the initial Young's modulus, elastic Young's modulus, maximal stress, and maximal and mid-strain values. The stress-strain curves show a large variation, with an average Young's modules in the toe and linear regions of 0.1 MPa and 21 MPa. We performed a comprehensive analysis of the correlation between the key mechanical properties with age and with microstructural parameters, e.g., fiber density, thickness, and orientation. Age was found to correlate negatively with Young's modulus and collagen density. Moreover, real-time monitoring during uniaxial stretching allowed us to observe changes in collagen and elastin alignment. Elastin fibers aligned significantly in both the heel and linear regions, and the collagen bundles engaged and oriented mainly in the linear region. This research advances our understanding of skin biomechanics and yields input for future first principles full modeling of skin tissue.
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Affiliation(s)
- Mengyao Zhou
- Faculty of Science, Department of Physics, Laserlab, Vrije Universiteit Amsterdam, De Boelelaan 1105, 1081HV, Amsterdam, The Netherlands.
| | - Patrick José González
- Faculty of Science, Department of Physics, Laserlab, Vrije Universiteit Amsterdam, De Boelelaan 1105, 1081HV, Amsterdam, The Netherlands
| | - Ludo Van Haasterecht
- Faculty of Science, Department of Physics, Laserlab, Vrije Universiteit Amsterdam, De Boelelaan 1105, 1081HV, Amsterdam, The Netherlands
- Burn Center and Department of Plastic, Reconstructive and Hand Surgery, Red Cross Hospital, Mozartstraat 201, 1962 AB, Beverwijk, The Netherlands
- Department of Plastic, Reconstructive and Hand Surgery, Amsterdam University Medical Center (UMC), Location Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands
| | - Alperen Soylu
- Faculty of Science, Department of Physics, Laserlab, Vrije Universiteit Amsterdam, De Boelelaan 1105, 1081HV, Amsterdam, The Netherlands
| | - Maria Mihailovski
- Faculty of Science, Department of Physics, Laserlab, Vrije Universiteit Amsterdam, De Boelelaan 1105, 1081HV, Amsterdam, The Netherlands
| | - Paul Van Zuijlen
- Burn Center and Department of Plastic, Reconstructive and Hand Surgery, Red Cross Hospital, Mozartstraat 201, 1962 AB, Beverwijk, The Netherlands
- Department of Plastic, Reconstructive and Hand Surgery, Amsterdam University Medical Center (UMC), Location Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands
- Pediatric Surgical Centre, Emma Children's Hospital, Amsterdam University Medical Center (UMC), Location University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Movement Sciences (AMS) Institute, Amsterdam University Medical Center (UMC), Location Vrije Universiteit Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
| | - Marie Louise Groot
- Faculty of Science, Department of Physics, Laserlab, Vrije Universiteit Amsterdam, De Boelelaan 1105, 1081HV, Amsterdam, The Netherlands
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3
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Fernandez-Carro E, Remacha AR, Orera I, Lattanzio G, Garcia-Barrios A, del Barrio J, Alcaine C, Ciriza J. Human Dermal Decellularized ECM Hydrogels as Scaffolds for 3D In Vitro Skin Aging Models. Int J Mol Sci 2024; 25:4020. [PMID: 38612828 PMCID: PMC11011913 DOI: 10.3390/ijms25074020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 04/01/2024] [Accepted: 04/02/2024] [Indexed: 04/14/2024] Open
Abstract
Biomaterials play an important role in the development of advancing three dimensional (3D) in vitro skin models, providing valuable insights for drug testing and tissue-specific modeling. Commercial materials, such as collagen, fibrin or alginate, have been widely used in skin modeling. However, they do not adequately represent the molecular complexity of skin components. On this regard, the development of novel biomaterials that represent the complexity of tissues is becoming more important in the design of advanced models. In this study, we have obtained aged human decellularized dermal extracellular matrix (dECM) hydrogels extracted from cadaveric human skin and demonstrated their potential as scaffold for advanced skin models. These dECM hydrogels effectively reproduce the complex fibrillar structure of other common scaffolds, exhibiting similar mechanical properties, while preserving the molecular composition of the native dermis. It is worth noting that fibroblasts embedded within human dECM hydrogels exhibit a behavior more representative of natural skin compared to commercial collagen hydrogels, where uncontrolled cell proliferation leads to material shrinkage. The described human dECM hydrogel is able to be used as scaffold for dermal fibroblasts in a skin aging-on-a-chip model. These results demonstrate that dECM hydrogels preserve essential components of the native human dermis making them a suitable option for the development of 3D skin aging models that accurately represent the cellular microenvironment, improving existing in vitro skin models and allowing for more reliable results in dermatopathological studies.
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Affiliation(s)
- Estibaliz Fernandez-Carro
- Tissue Microenvironment (TME) Lab, Aragón Institute of Engineering Research (I3A), University of Zaragoza, C/Mariano Esquillor s/n, 500018 Zaragoza, Spain; (E.F.-C.); (C.A.)
- Institute for Health Research Aragón (IIS Aragón), Avda. San Juan Bosco, 13, 50009 Zaragoza, Spain
| | - Ana Rosa Remacha
- Tissue Microenvironment (TME) Lab, Aragón Institute of Engineering Research (I3A), University of Zaragoza, C/Mariano Esquillor s/n, 500018 Zaragoza, Spain; (E.F.-C.); (C.A.)
| | - Irene Orera
- Proteomics Research Core Facility, Instituto Aragonés de Ciencias de la Salud (IACS), 50009 Zaragoza, Spain; (I.O.)
| | - Giuseppe Lattanzio
- Proteomics Research Core Facility, Instituto Aragonés de Ciencias de la Salud (IACS), 50009 Zaragoza, Spain; (I.O.)
| | - Alberto Garcia-Barrios
- Department of Anatomy and Histology, Faculty of Medicine, University of Zaragoza, 50009 Zaragoza, Spain
| | - Jesús del Barrio
- Departamento de Química Orgánica, Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain;
| | - Clara Alcaine
- Tissue Microenvironment (TME) Lab, Aragón Institute of Engineering Research (I3A), University of Zaragoza, C/Mariano Esquillor s/n, 500018 Zaragoza, Spain; (E.F.-C.); (C.A.)
- Institute for Health Research Aragón (IIS Aragón), Avda. San Juan Bosco, 13, 50009 Zaragoza, Spain
| | - Jesús Ciriza
- Tissue Microenvironment (TME) Lab, Aragón Institute of Engineering Research (I3A), University of Zaragoza, C/Mariano Esquillor s/n, 500018 Zaragoza, Spain; (E.F.-C.); (C.A.)
- Institute for Health Research Aragón (IIS Aragón), Avda. San Juan Bosco, 13, 50009 Zaragoza, Spain
- Department of Anatomy and Histology, Faculty of Medicine, University of Zaragoza, 50009 Zaragoza, Spain
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid, Spain
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4
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Diosa JG, Moreno R, Chica EL, Buganza-Tepole A. Impact of Indenter Size and Microrelief Anisotropy on the Tribological Behavior of Human Skin. J Biomech Eng 2023; 145:101008. [PMID: 37382599 DOI: 10.1115/1.4062848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 06/21/2023] [Indexed: 06/30/2023]
Abstract
Everyday, we interact with screens, sensors, and many other devices through contact with the skin. Experimental efforts have increased our knowledge of skin tribology but are challenged by the fact that skin has a complex structure, undergoes finite deformations, has nonlinear material response, and has properties that vary with anatomical location, age, sex, and environmental conditions. Computational models are powerful tools to dissect the individual contribution of these variables to the overall frictional response. Here, we present a three-dimensional high-fidelity multilayer skin computational model including a detailed surface topography or skin microrelief. Four variables are explored: local coefficient of friction (COF), indenter size, mechanical properties of the stratum corneum, and displacement direction. The results indicate that the global COF depends nonlinearly on the local COF, implying a role for skin deformation on the friction response. The global COF is also influenced by the ratio of the indenter size to the microrelief features, with larger indenters smoothing out the role of skin topography. Changes in stiffness of the uppermost layer of skin associated with humidity have a substantial effect on both the contact area and the reaction forces, but the overall changes in the COF are small. Finally, for the microrelief tested, the response can be considered isotropic. We anticipate that this model and results will enable the design of materials and devices for a desired interaction against skin.
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Affiliation(s)
- Juan G Diosa
- Department of Biomedical Engineering, Universidad CES, Medellín 050021, Colombia; Mechanical Engineering Department, Universidad de Antioquia, Medellín 050010, Colombia
| | - Ricardo Moreno
- Mechanical Engineering Department, Universidad de Antioquia, Medellín 050010, Colombia
| | - Edwin L Chica
- Mechanical Engineering Department, Universidad de Antioquia, Medellín 050010, Colombia
| | - Adrian Buganza-Tepole
- School of Mechanical Engineering, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907
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5
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Ayadh M, Guillermin A, Abellan MA, Bigouret A, Zahouani H. The assessment of natural human skin tension orientation and its variation according to age for two body areas: Forearm and thigh. J Mech Behav Biomed Mater 2023; 141:105798. [PMID: 36996528 DOI: 10.1016/j.jmbbm.2023.105798] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 08/23/2022] [Accepted: 03/23/2023] [Indexed: 03/30/2023]
Abstract
Human skin has a complex multilayer structure consisting of non-homogeneous, non-linear, viscoelastic and anisotropic materials subjected to in vivo natural pre-tension. This natural tension stems from networks of collagen and elastin fibers. The 3D organization of the collagen and elastin fibers underpins the multidirectional natural tensions in the skin volume while the state of the networks formed influences the surface topography of the skin. This topography depends on the area of the body and on the age of the person. Experiments reported in the literature have been performed ex vivo or on cadavers. By contrast, this work proposes the characterization of the anisotropic natural tension of the human skin in vivo. Experimental tests were performed on the forearms and thighs of 42 female volunteers representing two age groups [20 - 30] and [45-55] years old. Non-contact impact tests and skin-folding tests were conducted using devices developed at the LTDS (Lyon, France). The impact test generated a Rayleigh wave that spread in the skin. The speed of this wave was measured in 7 directions to study the anisotropy of the skin tension. The image of the skin relief at rest and during the skin folding test was reconstructed by optical confocal microscopy and provided the density of the skin lines printed on the outer surface of the skin. Skin folding test enables the clinician's manual procedure to be instrumented to identify tension lines i.e., Langer lines, for better healing during a surgical procedure. The main directions of natural skin tension deduced from the measured wave speed and the densities of skin lines were [40°-60°] for the forearm and [0°-20°] for the thigh, considering that the longitudinal axis of the body is situated at 90° and the transversal axis at 0°. This method shows the remarkable effect of age and body area on the mechanical behavior of human skin in vivo. The elastic properties and natural tension of the skin decrease with age. This decrease is greater in the directions orthogonal to the skin's tension lines, leading to the accentuation of the anisotropic behavior of the cutaneous tissue. The main direction of skin tension is highly dependent on the area of the body and is directed towards a preferred direction which corresponds to the main direction of skin tension.
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6
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de Lucio M, Leng Y, Hans A, Bilionis I, Brindise M, Ardekani AM, Vlachos PP, Gomez H. Modeling large-volume subcutaneous injection of monoclonal antibodies with anisotropic porohyperelastic models and data-driven tissue layer geometries. J Mech Behav Biomed Mater 2023; 138:105602. [PMID: 36529050 DOI: 10.1016/j.jmbbm.2022.105602] [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: 06/30/2022] [Revised: 11/22/2022] [Accepted: 11/29/2022] [Indexed: 12/13/2022]
Abstract
Subcutaneous injection of therapeutic monoclonal antibodies (mAbs) has become one of the fastest-growing fields in the pharmaceutical industry. The transport and mechanical processes behind large volume injections are poorly understood. Here, we leverage a large-deformation poroelastic model to study high-dose, high-speed subcutaneous injection. We account for the anisotropy of subcutaneous tissue using of a fibril-reinforced porohyperelastic model. We also incorporate the multi-layer structure of the skin tissue, generating data-driven geometrical models of the tissue layers using histological data. We analyze the impact of handheld autoinjectors on the injection dynamics for different patient forces. Our simulations show the importance of considering the large deformation approach to model large injection volumes. This work opens opportunities to better understand the mechanics and transport processes that occur in large-volume subcutaneous injections of mAbs.
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Affiliation(s)
- Mario de Lucio
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette IN 47907, USA
| | - Yu Leng
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette IN 47907, USA
| | - Atharva Hans
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette IN 47907, USA
| | - Ilias Bilionis
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette IN 47907, USA
| | - Melissa Brindise
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette IN 47907, USA
| | - Arezoo M Ardekani
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette IN 47907, USA
| | - Pavlos P Vlachos
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette IN 47907, USA
| | - Hector Gomez
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette IN 47907, USA.
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7
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Drug delivery with dissolving microneedles: Skin puncture, its influencing factors and improvement strategies. J Drug Deliv Sci Technol 2022. [DOI: 10.1016/j.jddst.2022.103653] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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8
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Kirby MA, Tang P, Liou HC, Kuriakose M, Pitre JJ, Pham TN, Ettinger RE, Wang RK, O'Donnell M, Pelivanov I. Probing elastic anisotropy of human skin in vivo with light using non-contact acoustic micro-tapping OCE and polarization sensitive OCT. Sci Rep 2022; 12:3963. [PMID: 35273250 PMCID: PMC8913799 DOI: 10.1038/s41598-022-07775-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 02/24/2022] [Indexed: 12/19/2022] Open
Abstract
Skin broadly protects the human body from undesired factors such as ultraviolet radiation and abrasion and helps conserve body temperature and hydration. Skin's elasticity and its level of anisotropy are key to its aesthetics and function. Currently, however, treatment success is often speculative and subjective, and is rarely based on skin's elastic properties because there is no fast and accurate non-contact method for imaging of skin's elasticity. Here we report on a non-contact and non-invasive method to image and characterize skin's elastic anisotropy. It combines acoustic micro-tapping optical coherence elastography (AμT-OCE) with a nearly incompressible transversely isotropic (NITI) model to quantify skin's elastic moduli. In addition, skin sites were imaged with polarization sensitive optical coherence tomography (PS-OCT) to help define fiber orientation. Forearm skin areas were investigated in five volunteers. Results clearly demonstrate elastic anisotropy of skin in all subjects. AμT-OCE has distinct advantages over competitive techniques because it provides objective, quantitative characterization of skin's elasticity without contact, which opens the door for broad translation into clinical use. Finally, we demonstrate that a combination of multiple OCT modalities (structural OCT, OCT angiography, PS-OCT and AμT-OCE) may provide rich information about skin and can be used to characterize scar.
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Affiliation(s)
- Mitchell A Kirby
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Peijun Tang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Hong-Cin Liou
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Maju Kuriakose
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - John J Pitre
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Tam N Pham
- Harborview Medical Center, University of Washington, Seattle, WA, USA
| | | | - Ruikang K Wang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Matthew O'Donnell
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Ivan Pelivanov
- Department of Bioengineering, University of Washington, Seattle, WA, USA.
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9
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Spartacus V, Shojaeizadeh M, Raffault V, Shoults J, Van Wieren K, Sparrey CJ. In vivo soft tissue compressive properties of the human hand. PLoS One 2021; 16:e0261008. [PMID: 34898632 PMCID: PMC8668133 DOI: 10.1371/journal.pone.0261008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 11/22/2021] [Indexed: 12/25/2022] Open
Abstract
Background/Purpose Falls onto outstretched hands are the second most common sports injury and one of the leading causes of upper extremity injury. Injury risk and severity depends on forces being transmitted through the palmar surface to the upper extremity. Although the magnitude and distribution of forces depend on the soft tissue response of the palm, the in vivo properties of palmar tissue have not been characterized. The purpose of this study was to characterize the large deformation palmar soft tissue properties. Methods In vivo dynamic indentations were conducted on 15 young adults (21–29 years) to quantify the soft tissue characteristics of over the trapezium. The effects of loading rate, joint position, tissue thickness and sex on soft tissue responses were assessed. Results Energy absorbed by the soft tissue and peak force were affected by loading rate and joint angle. Energy absorbed was 1.7–2.8 times higher and the peak force was 2–2.75 times higher at high rate loading than quasistatic rates. Males had greater energy absorbed than females but not at all wrist positions. Damping characteristics were the highest in the group with the thickest soft tissue while damping characteristics were the lowest in group with the thinnest soft tissues. Conclusion Palmar tissue response changes with joint position, loading rate, sex, and tissue thickness. Accurately capturing these tissue responses is important for developing effective simulations of fall and injury biomechanics and assessing the effectiveness of injury prevention strategies.
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Affiliation(s)
- Victoria Spartacus
- Mechatronic Systems Engineering, Simon Fraser University, Surrey, British Columbia, Canada
- * E-mail:
| | - Maedeh Shojaeizadeh
- Mechatronic Systems Engineering, Simon Fraser University, Surrey, British Columbia, Canada
| | - Vincent Raffault
- Mechatronic Systems Engineering, Simon Fraser University, Surrey, British Columbia, Canada
| | - James Shoults
- Science Technical Center, Simon Fraser University, Burnaby, BC, Canada
| | - Ken Van Wieren
- Science Technical Center, Simon Fraser University, Burnaby, BC, Canada
| | - Carolyn J. Sparrey
- Mechatronic Systems Engineering, Simon Fraser University, Surrey, British Columbia, Canada
- International Collaboration on Repair Discoveries (ICORD), Vancouver, British Columbia, Canada
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10
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Diosa JG, Moreno R, Chica EL, Villarraga JA, Tepole AB. Changes in the three-dimensional microscale topography of human skin with aging impact its mechanical and tribological behavior. PLoS One 2021; 16:e0241533. [PMID: 34242217 PMCID: PMC8270165 DOI: 10.1371/journal.pone.0241533] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 05/11/2021] [Indexed: 11/19/2022] Open
Abstract
Human skin enables interaction with diverse materials every day and at all times. The ability to grasp objects, feel textures, and perceive the environment depends on the mechanical behavior, complex structure, and microscale topography of human skin. At the same time, abrasive interactions, such as sometimes occur with prostheses or textiles, can damage the skin and impair its function. Previous theoretical and computational efforts have shown that skin’s surface topography or microrelief is crucial for its tribological behavior. However, current understanding is limited to adult surface profiles and simplified two-dimensional simulations. Yet, the skin has a rich set of features in three dimensions, and the geometry of skin is known to change with aging. Here we create a numerical model of a dynamic indentation test to elucidate the effect of changes in microscale topography with aging on the skin’s response under indentation and sliding contact with a spherical indenter. We create three different microrelief geometries representative of different ages based on experimental reports from the literature. We perform the indentation and sliding steps, and calculate the normal and tangential forces on the indenter as it moves in three distinct directions based on the characteristic skin lines. The model also evaluates the effect of varying the material parameters. Our results show that the microscale topography of the skin in three dimensions, together with the mechanical behavior of the skin layers, lead to distinctive trends on the stress and strain distribution. The major finding is the increasing role of anisotropy which emerges from the geometric changes seen with aging.
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Affiliation(s)
- Juan G. Diosa
- Mechanical Engineering Department, Universidad de Antioquia, Medellín, Colombia
| | - Ricardo Moreno
- Mechanical Engineering Department, Universidad de Antioquia, Medellín, Colombia
| | - Edwin L. Chica
- Mechanical Engineering Department, Universidad de Antioquia, Medellín, Colombia
| | - Junes A. Villarraga
- Mechanical Engineering Department, Universidad de Antioquia, Medellín, Colombia
| | - Adrian B. Tepole
- School of Mechanical Engineering, Purdue University, West Lafayette, Indiana, United States of America
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana, United States of America
- * E-mail:
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11
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Torossian K, Ottenio M, Brulez AC, Lafon Y, Viste A, Attali P, Benayoun S. Biomechanical analysis of practitioner's gesture for peripheral venous catheter insertion. Med Eng Phys 2021; 90:92-99. [PMID: 33781485 DOI: 10.1016/j.medengphy.2021.03.001] [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: 09/14/2020] [Revised: 01/10/2021] [Accepted: 03/01/2021] [Indexed: 11/24/2022]
Abstract
Peripheral venous catheter insertion (PVCI) is one of the most common procedures performed by healthcare professionals but remains technically difficult. To develop new medical simulators with better representativeness of the human forearm, an experimental study was performed to collect data related to the puncturing of human skin and a vein in the antebrachial area. A total of 31 volunteers participated in this study. Force sensors and digital image correlation were used to measure the force during the palpation and puncturing of the vein and to retrieve the kinematics of the practitioner's gesture. The in vivo skin rupture load, vein rupture load, and friction loads for skin only and for both the skin and vein were (mean ± standard deviation) 0.85 ± 0.34 N, 1.25 ± 0.37 N, -0.49 ± 0.19 N, and -0.51 ± 0.16 N, respectively. The results of this study can be used to develop realistic skin and vein substitutes and mechanically assess them by reproducing the practitioner's gesture in a controlled fashion.
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Affiliation(s)
- K Torossian
- Laboratoire de Tribologie et Dynamique des Systèmes, UMR CNRS 5513, Ecole Centrale de Lyon, 36 avenue Guy de Collongues, 69134 Ecully, France; Univ Lyon, Université Claude Bernard Lyon 1, Univ Gustave Eiffel, IFSTTAR, LBMC UMR_T9406, F69622 Lyon, France.
| | - M Ottenio
- Univ Lyon, Université Claude Bernard Lyon 1, Univ Gustave Eiffel, IFSTTAR, LBMC UMR_T9406, F69622 Lyon, France
| | - A-C Brulez
- Laboratoire de Génie de la Fonctionnalisation des Matériaux Polymères, Institut Textile et Chimique de Lyon, 87 chemin des Mouilles, 69134 Ecully cedex, France
| | - Y Lafon
- Univ Lyon, Université Claude Bernard Lyon 1, Univ Gustave Eiffel, IFSTTAR, LBMC UMR_T9406, F69622 Lyon, France
| | - A Viste
- Univ Lyon, Université Claude Bernard Lyon 1, Univ Gustave Eiffel, IFSTTAR, LBMC UMR_T9406, F69622 Lyon, France; Hospices Civils de Lyon, Hôpital Lyon Sud, Chirurgie Orthopédique, 165 Chemin du Grand Revoyet, 69495 Pierre Benite Cedex, France
| | - P Attali
- Institut de Formation en Soins Infirmiers, 5 Avenue Esquirol, 69003 Lyon, France
| | - S Benayoun
- Laboratoire de Tribologie et Dynamique des Systèmes, UMR CNRS 5513, Ecole Centrale de Lyon, 36 avenue Guy de Collongues, 69134 Ecully, France
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12
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Runel G, Cario M, Lopez‐Ramirez N, Malbouyres M, Ruggiero F, Bernard L, Puisieux A, Caramel J, Chlasta J, Masse I. Stiffness measurement is a biomarker of skin ageing in vivo. Exp Dermatol 2020; 29:1233-1237. [DOI: 10.1111/exd.14195] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 09/10/2020] [Indexed: 02/06/2023]
Affiliation(s)
- Gaël Runel
- Centre de Recherche en Cancérologie de Lyon CNRS UMR5286 Inserm U1052 Université Lyon 1 Université de Lyon Lyon France
- BioMeca Lyon France
| | - Muriel Cario
- Inserm 1035 University of Bordeaux Bordeaux France
| | - Noémie Lopez‐Ramirez
- Centre de Recherche en Cancérologie de Lyon CNRS UMR5286 Inserm U1052 Université Lyon 1 Université de Lyon Lyon France
| | - Marilyne Malbouyres
- ENS de Lyon, CNRS Université Lyon 1 Institut de Génomique Fonctionnelle de Lyon UMR 5242 Université Lyon Lyon Cedex 07 France
| | - Florence Ruggiero
- ENS de Lyon, CNRS Université Lyon 1 Institut de Génomique Fonctionnelle de Lyon UMR 5242 Université Lyon Lyon Cedex 07 France
| | - Laure Bernard
- ENS de Lyon, CNRS Université Lyon 1 Institut de Génomique Fonctionnelle de Lyon UMR 5242 Université Lyon Lyon Cedex 07 France
- SFR Biosciences, ENS de Lyon Inserm US8 CNRS UMS3444 Univ Lyon Lyon France
| | - Alain Puisieux
- Centre de Recherche en Cancérologie de Lyon CNRS UMR5286 Inserm U1052 Université Lyon 1 Université de Lyon Lyon France
| | - Julie Caramel
- Centre de Recherche en Cancérologie de Lyon CNRS UMR5286 Inserm U1052 Université Lyon 1 Université de Lyon Lyon France
| | | | - Ingrid Masse
- Centre de Recherche en Cancérologie de Lyon CNRS UMR5286 Inserm U1052 Université Lyon 1 Université de Lyon Lyon France
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13
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Thieulin C, Pailler-Mattei C, Abdouni A, Djaghloul M, Zahouani H. Mechanical and topographical anisotropy for human skin: Ageing effect. J Mech Behav Biomed Mater 2019; 103:103551. [PMID: 32090946 DOI: 10.1016/j.jmbbm.2019.103551] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 10/30/2019] [Accepted: 11/20/2019] [Indexed: 11/25/2022]
Abstract
Skin ageing is a complex process which strongly impacts the three skin layers (epidermis, dermis, hypodermis) both functionally and structurally. Of particular interest are the effects of ageing on the dermis biomechanics and how this evolution can impact the reorganization of the cutaneous lines which compose the skin relief. It has been argued that the skin relief could reflect the underlying mechanical condition of the skin. Nevertheless, there is not yet conclusive evidence of the existence of such a link. This work aims at experimentally studying, in vivo, the correlation between the anisotropy of human skin biomechanics and skin topography as a function of ageing. The study was conducted on a panel of 20 men divided into 4 groups according to age (from 23 to 64 years old). The measurements were performed on the right volar forearm of each volunteer. For the biomechanical measurements, an innovative contactless bio-rheometer was developed. It allows access to the mechanical behaviour of the skin in several directions. This device generates an air blast without any contact with the skin area and measures its dynamic response (evaluation of speed of wave propagation) with a linear laser. Moreover, a turntable enables measurements to be made in different angular directions. To analyse the topography of skin relief, we proposed a new method, based on watershed and linear radon transformations. First, an optical analysis of a replica of the skin relief is performed. Then, from the skin image obtained, the density of the cutaneous lines is calculated in different directions using watersheld transformation. The orientation of the detected lines is then estimated with an algorithm based on linear radon transformation. The results observed show a good correlation between the skin relief and the mechanical properties of the skin all along the ageing process. For both topography and mechanical properties, there is a transition from an almost isotropic mechanical behaviour to an anisotropic one as a function of ageing process. Thus, we might conclude that the skin relief reflects the underlying mechanical conditions of the skin.
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Affiliation(s)
- C Thieulin
- Laboratoire de Tribologie et Dynamique des Systèmes, UMR-CNRS 5513, Ecole Centrale de Lyon, 36 Avenue Guy de Collongue, Ecully, France.
| | - C Pailler-Mattei
- Laboratoire de Tribologie et Dynamique des Systèmes, UMR-CNRS 5513, Ecole Centrale de Lyon, 36 Avenue Guy de Collongue, Ecully, France; Université de Lyon, Faculté de Pharmacie-ISPB, Laboratoire de Biophysique, Lyon, France
| | - A Abdouni
- Laboratoire de Tribologie et Dynamique des Systèmes, UMR-CNRS 5513, Ecole Centrale de Lyon, 36 Avenue Guy de Collongue, Ecully, France
| | - M Djaghloul
- Laboratoire de Tribologie et Dynamique des Systèmes, UMR-CNRS 5513, Ecole Centrale de Lyon, 36 Avenue Guy de Collongue, Ecully, France
| | - H Zahouani
- Laboratoire de Tribologie et Dynamique des Systèmes, UMR-CNRS 5513, Ecole Centrale de Lyon, 36 Avenue Guy de Collongue, Ecully, France
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14
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Torossian K, Benayoun S, Ottenio M, Brulez AC. Guidelines for designing a realistic peripheral venous catheter insertion simulator: A literature review. Proc Inst Mech Eng H 2019; 233:963-978. [DOI: 10.1177/0954411919864786] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A literature review was conducted to develop more realistic medical simulators that better prepare aspiring health professionals to perform a medical procedure in vivo. Thus, this review proposes an approach that might assist researchers design improved medical simulators, particularly new materials that would enhance the sensation of touch for skin substitutes. By targeting the current needs in the field of simulation learning, we concluded that peripheral venous catheter insertion simulators lack realistic haptic feedback. Enhanced peripheral venous catheter insertion simulators will accelerate the mastery of the medical procedure, thus decreasing the number of failures in patients and costs related to this procedure.
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Affiliation(s)
- Kevin Torossian
- Laboratoire de Tribologie et Dynamique des Systèmes, UMR CNRS 5513, Ecole Centrale de Lyon, Écully, France
- Univ Lyon, Université Claude Bernard Lyon 1, IFSTTAR, LBMC UMR_T9406, Lyon, France
| | - Stéphane Benayoun
- Laboratoire de Tribologie et Dynamique des Systèmes, UMR CNRS 5513, Ecole Centrale de Lyon, Écully, France
| | - Mélanie Ottenio
- Univ Lyon, Université Claude Bernard Lyon 1, IFSTTAR, LBMC UMR_T9406, Lyon, France
| | - Anne-Catherine Brulez
- Laboratoire de Génie de la Fonctionnalisation des Matériaux Polymères, Institut Textile et Chimique de Lyon, Écully, France
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15
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In vivo adhesive behavior of human facial skin by a modified indentation test. J Mech Behav Biomed Mater 2019; 92:172-178. [DOI: 10.1016/j.jmbbm.2019.01.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Revised: 01/22/2019] [Accepted: 01/25/2019] [Indexed: 10/27/2022]
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16
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Limbert G, Masen MA, Pond D, Graham HK, Sherratt MJ, Jobanputra R, McBride A. Biotribology of the ageing skin—Why we should care. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.biotri.2019.03.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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17
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Dai A, Wang S, Zhou L, Wei H, Wang Z, He W. In vivo mechanical characterization of human facial skin combining curved surface imaging and indentation techniques. Skin Res Technol 2018; 25:142-149. [DOI: 10.1111/srt.12623] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 06/23/2018] [Indexed: 11/28/2022]
Affiliation(s)
- Anna Dai
- Department of MechanicsTianjin University Tianjin China
| | - Shibin Wang
- Department of MechanicsTianjin University Tianjin China
| | - Lei Zhou
- Department of MechanicsTianjin University Tianjin China
| | - Huixin Wei
- Department of MechanicsTianjin University Tianjin China
| | - Zhiyong Wang
- Department of MechanicsTianjin University Tianjin China
| | - Wei He
- AMLDepartment of Engineering MechanicsTsinghua University Beijing China
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18
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Kruglikov IL, Scherer PE. Skin aging as a mechanical phenomenon: The main weak links. NUTRITION AND HEALTHY AGING 2018; 4:291-307. [PMID: 29951590 PMCID: PMC6004930 DOI: 10.3233/nha-170037] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
From a mechanical point of view, human skin appears as a layered composite containing the stiff thin cover layer presented by the stratum corneum, below which are the more compliant layers of viable epidermis and dermis and further below the much more compliant adjacent layer of subcutaneous white adipose tissue (sWAT). Upon exposure to a strain, such a multi-layer system demonstrates structural instabilities in its stiffer layers, which in its simplest form is the wrinkling. These instabilities appear hierarchically when the mechanical strain in the skin exceeds some critical values. Their appearance is mainly dependent on the mismatch in mechanical properties between adjacent skin layers or between the skin and sWAT, on the adhesive strength and thickness ratios between the layers, on their bending and tensile stiffness as well as on the value of the stress existing in single layers. Gradual reduction of elastic fibers in aging significantly reduces the skin's ability to bend, prompting an up to 4-fold reduction of its stability against wrinkling, thereby explaining the role of these fibers in skin aging. While chronological and extrinsic aging differently modify these parameters, they lead to the same end result, reducing the critical strain required for the onset of instabilities. Comparing of mechanical properties of the skin presented as a bi-, tri- or tetra-layer structure demonstrates the particular importance of the papillary dermis in skin aging and provides the arguments to consider the undulations on the dermal-epidermal and dermal-sWAT interfaces as the result of mechanical bifurcation, leading to structural instabilities inside of the skin. According to this model, anti-aging strategies should focus not as much on the reinforcement of the dermis, but rather aim to treat the elastic mismatch between different adjacent layers in the skin and sWAT as well as the adhesion between these layers.
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Affiliation(s)
| | - Philipp E. Scherer
- Department of Internal Medicine, Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
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19
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Abdouni A, Djaghloul M, Thieulin C, Vargiolu R, Pailler-Mattei C, Zahouani H. Biophysical properties of the human finger for touch comprehension: influences of ageing and gender. ROYAL SOCIETY OPEN SCIENCE 2017; 4:170321. [PMID: 28878982 PMCID: PMC5579097 DOI: 10.1098/rsos.170321] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 07/10/2017] [Indexed: 05/19/2023]
Abstract
The human finger plays an extremely important role in tactile perception, but little is known about how age and gender affect its biophysical properties and their role in tactile perception. We combined studies on contact characteristics, mechanical properties and surface topography to understand age and gender effects on the human finger. The values obtained regarding contact characteristics (i.e. adhesive force) were significantly higher for women than for men. As for mechanical properties (i.e. Young's modulus E), a significant and positive correlation with age was observed and found to be higher for women. A positive correlation was observed between age and the arithmetic mean of surface roughness for men. However, an inverse age effect was highlighted for women. The age and gender effects obtained have never been reported previously in the literature. These results open new perspectives for understanding the weakening of tactile perception across ages and how it differs between men and women.
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Affiliation(s)
- A. Abdouni
- Laboratoire de Tribologie et Dynamique des Systèmes-LTDS UMR-CNRS 5513, Université de Lyon, ECL-ENISE, 69134 Ecully, France
- Author for correspondence: A. Abdouni e-mail:
| | - M. Djaghloul
- Laboratoire de Tribologie et Dynamique des Systèmes-LTDS UMR-CNRS 5513, Université de Lyon, ECL-ENISE, 69134 Ecully, France
| | - C. Thieulin
- Laboratoire de Tribologie et Dynamique des Systèmes-LTDS UMR-CNRS 5513, Université de Lyon, ECL-ENISE, 69134 Ecully, France
| | - R. Vargiolu
- Laboratoire de Tribologie et Dynamique des Systèmes-LTDS UMR-CNRS 5513, Université de Lyon, ECL-ENISE, 69134 Ecully, France
| | - C. Pailler-Mattei
- Laboratoire de Tribologie et Dynamique des Systèmes-LTDS UMR-CNRS 5513, Université de Lyon, ECL-ENISE, 69134 Ecully, France
- Laboratoire de Biophysique, Faculté de Pharmacie-ISPB, Université Lyon 1, 69008 Lyon, France
| | - H. Zahouani
- Laboratoire de Tribologie et Dynamique des Systèmes-LTDS UMR-CNRS 5513, Université de Lyon, ECL-ENISE, 69134 Ecully, France
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20
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New regime in the mechanical behavior of skin: strain-softening occurring before strain-hardening. J Mech Behav Biomed Mater 2017; 69:98-106. [DOI: 10.1016/j.jmbbm.2016.12.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 12/19/2016] [Accepted: 12/23/2016] [Indexed: 11/19/2022]
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21
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Rittié L, Farr EA, Orringer JS, Voorhees JJ, Fisher GJ. Reduced cell cohesiveness of outgrowths from eccrine sweat glands delays wound closure in elderly skin. Aging Cell 2016; 15:842-52. [PMID: 27184009 PMCID: PMC5013029 DOI: 10.1111/acel.12493] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/29/2016] [Indexed: 01/03/2023] Open
Abstract
Human skin heals more slowly in aged vs. young adults, but the mechanism for this delay is unclear. In humans, eccrine sweat glands (ESGs) and hair follicles underlying wounds generate cohesive keratinocyte outgrowths that expand to form the new epidermis. Here, we compared the re‐epithelialization of partial‐thickness wounds created on the forearm of healthy young (< 40 yo) and aged (> 70 yo) adults. Our results confirm that the outgrowth of cells from ESGs is a major feature of repair in young skin. Strikingly, in aged skin, although ESG density is unaltered, less than 50% of the ESGs generate epithelial outgrowths during repair (vs. 100% in young). Surprisingly, aging does not alter the wound‐induced proliferation response in hair follicles or ESGs. Instead, there is an overall reduced cohesiveness of keratinocytes in aged skin. Reduced cell–cell cohesiveness was most obvious in ESG‐derived outgrowths that, when present, were surrounded by unconnected cells in the scab overlaying aged wounds. Reduced cell–cell contact persisted during the repair process, with increased intercellular spacing and reduced number of desmosomes. Together, reduced outgrowths of ESG (i) reduce the initial number of cells participating in epidermal repair, (ii) delay wound closure, and (iii) lead to a thinner repaired epidermis in aged vs. young skin. Failure to form cohesive ESG outgrowths may reflect impaired interactions of keratinocytes with the damaged ECM in aged skin. Our findings provide a framework to better understand the mediators of delayed re‐epithelialization in aging and further support the importance of ESGs for the repair of human wounds.
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Affiliation(s)
- Laure Rittié
- Department of Dermatology University of Michigan Medical School Ann Arbor MI USA
| | - Elyssa A. Farr
- Department of Dermatology University of Michigan Medical School Ann Arbor MI USA
| | - Jeffrey S. Orringer
- Department of Dermatology University of Michigan Medical School Ann Arbor MI USA
| | - John J. Voorhees
- Department of Dermatology University of Michigan Medical School Ann Arbor MI USA
| | - Gary J. Fisher
- Department of Dermatology University of Michigan Medical School Ann Arbor MI USA
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22
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Rittié L. Cellular mechanisms of skin repair in humans and other mammals. J Cell Commun Signal 2016; 10:103-20. [PMID: 27170326 PMCID: PMC4882309 DOI: 10.1007/s12079-016-0330-1] [Citation(s) in RCA: 166] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Accepted: 05/05/2016] [Indexed: 12/16/2022] Open
Abstract
The increased incidence of non-healing skin wounds in developed societies has prompted tremendous research efforts on the complex process known as "wound healing". Unfortunately, the weak relevance of modern wound healing research to human health continues to be a matter of concern. This review summarizes the current knowledge of the cellular mechanisms that mediate wound closure in the skin of humans and laboratory animals. The author highlights the anatomical singularities of human skin vs. the skin of other mammals commonly used for wound healing research (i.e. as mice, rats, rabbits, and pigs), and discusses the roles of stem cells, myofibroblasts, and the matrix environment in the repair process. The majority of this review focuses on reepithelialization and wound closure. Other aspects of wound healing (e.g. inflammation, fibrous healing) are referred to when relevant to the main topic. This review aims at providing the reader with a clear understanding of the similarities and differences that have been reported over the past 100 years between the healing of human wounds and that of other mammals.
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Affiliation(s)
- Laure Rittié
- Department of Dermatology, University of Michigan Medical School, 6447 Medical Building I, 1301 E. Catherine St., Ann Arbor, MI, 48109, USA.
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23
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Production of a Self-Aligned Scaffold, Free of Exogenous Material, from Dermal Fibroblasts Using the Self-Assembly Technique. Dermatol Res Pract 2016; 2016:5397319. [PMID: 27051415 PMCID: PMC4804048 DOI: 10.1155/2016/5397319] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 02/17/2016] [Indexed: 01/09/2023] Open
Abstract
Many pathologies of skin, especially ageing and cancer, involve modifications in the matrix alignment. Such tissue reorganization could have impact on cell behaviour and/or more global biological processes. Tissue engineering provides accurate study model by mimicking the skin and it allows the construction of versatile tridimensional models using human cells. It also avoids the use of animals, which gave sometimes nontranslatable results. Among the various techniques existing, the self-assembly method allows production of a near native skin, free of exogenous material. After cultivating human dermal fibroblasts in the presence of ascorbate during two weeks, a reseeding of these cells takes place after elevation of the resulting stroma on a permeable ring and culture pursued for another two weeks. This protocol induces a clear realignment of matrix fibres and cells parallel to the horizon. The thickness of this stretched reconstructed tissue is reduced compared to the stroma produced by the standard technique. Cell count is also reduced. In conclusion, a new, easy, and inexpensive method to produce aligned tissue free of exogenous material could be used for fundamental research applications in dermatology.
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24
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Tupin S, Molimard J, Cenizo V, Hoc T, Sohm B, Zahouani H. Multiscale Approach to Characterize Mechanical Properties of Tissue Engineered Skin. Ann Biomed Eng 2016; 44:2851-62. [PMID: 26942585 DOI: 10.1007/s10439-016-1576-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 02/18/2016] [Indexed: 10/22/2022]
Abstract
Tissue engineered skin usually consist of a multi-layered visco-elastic material composed of a fibrillar matrix and cells. The complete mechanical characterization of these tissues has not yet been accomplished. The purpose of this study was to develop a multiscale approach to perform this characterization in order to link the development process of a cultured skin to the mechanical properties. As a proof-of-concept, tissue engineered skin samples were characterized at different stages of manufacturing (acellular matrix, reconstructed dermis and reconstructed skin) for two different aging models (using cells from an 18- and a 61-year-old man). To assess structural variations, bi-photonic confocal microscopy was used. To characterize mechanical properties at a macroscopic scale, a light-load micro-mechanical device that performs indentation and relaxation tests was designed. Finally, images of the internal network of the samples under stretching were acquired by combining confocal microscopy with a tensile device. Mechanical properties at microscopic scale were assessed. Results revealed that adding cells during manufacturing induced structural changes, which provided higher elastic modulus and viscosity. Moreover, senescence models exhibited lower elastic modulus and viscosity. This multiscale approach was efficient to characterize and compare skin equivalent samples and permitted the first experimental assessment of the Poisson's ratio for such tissues.
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Affiliation(s)
- S Tupin
- Laboratoire de Tribologie et Dynamique des Systèmes (LTDS, CNRS UMR5513), Université de Lyon, Ecole Centrale de Lyon, ENISE, 69134, Ecully, France
| | - J Molimard
- Ecole Nationale Supérieure des Mines, CIS-EMSE, INSERM UMR1059, SAINBIOSE, 42023, Saint-Etienne, France
| | - V Cenizo
- BASF Beauty Care Solutions France S.A.S, 69366, Lyon Cedex 07, France
| | - T Hoc
- Laboratoire de Tribologie et Dynamique des Systèmes (LTDS, CNRS UMR5513), Université de Lyon, Ecole Centrale de Lyon, ENISE, 69134, Ecully, France
| | - B Sohm
- BASF Beauty Care Solutions France S.A.S, 69366, Lyon Cedex 07, France
| | - H Zahouani
- Laboratoire de Tribologie et Dynamique des Systèmes (LTDS, CNRS UMR5513), Université de Lyon, Ecole Centrale de Lyon, ENISE, 69134, Ecully, France.
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25
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Wong R, Geyer S, Weninger W, Guimberteau JC, Wong JK. The dynamic anatomy and patterning of skin. Exp Dermatol 2015; 25:92-8. [PMID: 26284579 DOI: 10.1111/exd.12832] [Citation(s) in RCA: 183] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/12/2015] [Indexed: 12/14/2022]
Abstract
The skin is often viewed as a static barrier that protects the body from the outside world. Emphasis on studying the skin's architecture and biomechanics in the context of restoring skin movement and function is often ignored. It is fundamentally important that if skin is to be modelled or developed, we do not only focus on the biology of skin but also aim to understand its mechanical properties and structure in living dynamic tissue. In this review, we describe the architecture of skin and patterning seen in skin as viewed from a surgical perspective and highlight aspects of the microanatomy that have never fully been realized and provide evidence or concepts that support the importance of studying living skin's dynamic behaviour. We highlight how the structure of the skin has evolved to allow the body dynamic form and function, and how injury, disease or ageing results in a dramatic changes to the microarchitecture and changes physical characteristics of skin. Therefore, appreciating the dynamic microanatomy of skin from the deep fascia through to the skin surface is vitally important from a dermatological and surgical perspective. This focus provides an alternative perspective and approach to addressing skin pathologies and skin ageing.
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Affiliation(s)
- Richard Wong
- Plastic Surgery Research, Centre of Dermatology, University of Manchester, Manchester, UK
| | - Stefan Geyer
- Center for Anatomy & Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Wolfgang Weninger
- Center for Anatomy & Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Jean-Claude Guimberteau
- De la Main et Plastique Reconstructice, Institut Aquitain de la Main Bordeaux, Pessac, France
| | - Jason K Wong
- Plastic Surgery Research, Centre of Dermatology, University of Manchester, Manchester, UK
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26
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Es'haghian S, Kennedy KM, Gong P, Sampson DD, McLaughlin RA, Kennedy BF. Optical palpation in vivo: imaging human skin lesions using mechanical contrast. JOURNAL OF BIOMEDICAL OPTICS 2015; 20:16013. [PMID: 25588164 DOI: 10.1117/1.jbo.20.1.016013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 12/04/2014] [Indexed: 05/02/2023]
Abstract
We demonstrate the first application of the recently proposed method of optical palpation to in vivo imaging of human skin. Optical palpation is a tactile imaging technique that probes the spatial variation of a sample's mechanical properties by producing an en face map of stress measured at the sample surface. This map is determined from the thickness of a translucent, compliant stress sensor placed between a loading element and the sample and is measured using optical coherence tomography. We assess the performance of optical palpation using a handheld imaging probe on skin-mimicking phantoms, and demonstrate its use on human skin lesions. Our results demonstrate the capacity of optical palpation to delineate the boundaries of lesions and to map the mechanical contrast between lesions and the surrounding normal skin.
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Affiliation(s)
- Shaghayegh Es'haghian
- The University of Western Australia, School of Electrical, Electronic and Computer Engineering, Optical+Biomedical Engineering Laboratory, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Kelsey M Kennedy
- The University of Western Australia, School of Electrical, Electronic and Computer Engineering, Optical+Biomedical Engineering Laboratory, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Peijun Gong
- The University of Western Australia, School of Electrical, Electronic and Computer Engineering, Optical+Biomedical Engineering Laboratory, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - David D Sampson
- The University of Western Australia, School of Electrical, Electronic and Computer Engineering, Optical+Biomedical Engineering Laboratory, 35 Stirling Highway, Crawley, Western Australia 6009, AustraliabThe University of Western Australia, Centre for Micr
| | - Robert A McLaughlin
- The University of Western Australia, School of Electrical, Electronic and Computer Engineering, Optical+Biomedical Engineering Laboratory, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Brendan F Kennedy
- The University of Western Australia, School of Electrical, Electronic and Computer Engineering, Optical+Biomedical Engineering Laboratory, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
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27
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Ottenio M, Tran D, Ní Annaidh A, Gilchrist MD, Bruyère K. Strain rate and anisotropy effects on the tensile failure characteristics of human skin. J Mech Behav Biomed Mater 2014; 41:241-50. [PMID: 25455608 DOI: 10.1016/j.jmbbm.2014.10.006] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 10/06/2014] [Accepted: 10/08/2014] [Indexed: 10/24/2022]
Abstract
The anisotropic failure characteristics of human skin are relatively unknown at strain rates typical in impact biomechanics. This study reports the results of an experimental protocol to quantify the effect of dynamic strain rates and the effect of sample orientation with respect to the Langer lines. Uniaxial tensile tests were carried out at three strain rates (0.06s(-1), 53s(-1), and 167s(-1)) on 33 test samples excised from the back of a fresh cadaver. The mean ultimate tensile stress, mean elastic modulus and mean strain energy increased with increasing strain rates. While the stretch ratio at ultimate tensile stress was not affected by the strain rate, it was influenced by the orientation of the samples (parallel and perpendicular to the Langer lines. The orientation of the sample also had a strong influence on the ultimate tensile stress, with a mean value of 28.0 ± 5.7 MPa for parallel samples, and 15.6 ± 5.2 MPa for perpendicular samples, and on the elastic modulus, with corresponding mean values of 160.8 MPa ± 53.2 MPa and 70.6 MPa ± 59.5 MPa. The study also pointed out the difficulties in controlling the effective applied strain rate in dynamic characterization of soft tissue and the resulting abnormal stress-strain relationships. Finally, data collected in this study can be used to develop constitutive models where high loading rates are of primary interest.
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Affiliation(s)
- Mélanie Ottenio
- Université de Lyon, F-69622, Lyon, France; Université Claude Bernard Lyon 1, Villeurbanne, France; IFSTTAR, UMR_T9406, LBMC Laboratoire de Biomécanique et Mécanique des Chocs, F69675, Bron, France.
| | - Doris Tran
- Université de Lyon, F-69622, Lyon, France; Université Claude Bernard Lyon 1, Villeurbanne, France; IFSTTAR, UMR_T9406, LBMC Laboratoire de Biomécanique et Mécanique des Chocs, F69675, Bron, France
| | - Aisling Ní Annaidh
- School of Mechanical & Materials Engineering, University College Dublin, Belfield, Dublin 4, Ireland
| | - Michael D Gilchrist
- School of Mechanical & Materials Engineering, University College Dublin, Belfield, Dublin 4, Ireland
| | - Karine Bruyère
- Université de Lyon, F-69622, Lyon, France; Université Claude Bernard Lyon 1, Villeurbanne, France; IFSTTAR, UMR_T9406, LBMC Laboratoire de Biomécanique et Mécanique des Chocs, F69675, Bron, France
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Rheological behaviour of reconstructed skin. J Mech Behav Biomed Mater 2014; 37:251-63. [DOI: 10.1016/j.jmbbm.2014.05.030] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 05/16/2014] [Accepted: 05/27/2014] [Indexed: 12/11/2022]
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Trojahn C, Schario M, Dobos G, Blume-Peytavi U, Kottner J. Reliability and validity of two in vivo measurements for skin surface topography in aged adults. Skin Res Technol 2014; 21:54-60. [PMID: 24863685 DOI: 10.1111/srt.12156] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/08/2014] [Indexed: 11/27/2022]
Abstract
BACKGROUND The non-contact optical methods phaseshift rapid in vivo measurement of skin (PRIMOS) and surface evaluation of living skin (SELS) are widely applied for measuring skin surface topography. The aims of the present study were to evaluate reliability and validity of these methods and to compare skin roughness intraindividually. METHODS SELS and PRIMOS measurements were performed on four skin areas of the left and right volar forearms in 12 healthy elderly subjects. Reliability and correlations were analyzed for Visioscan® and PRIMOS roughness parameters. Student's t-tests for estimating differences between contralateral volar forearm sites were applied. RESULTS ICC coefficients of the Visioscan® roughness estimates ranged between 0.50 and 0.95 and of the PRIMOS measurements between 0.01 and 1.00. The Visioscan® parameters SEr, SEsm, Rmax, and Rz, and the PRIMOS parameters Ra, Rz, Smax, Wt, and Sz showed most significant correlations with each other and to additional roughness parameters. Mean roughness differences between contralateral forearm skin areas ranged between 0.0 (SEsc) and 6.7 (Rmax). CONCLUSIONS The Visioscan® parameters SEr, Rmax, and Rz showed most reliable and valid values and were largely comparable on contralateral forearm skin sites in elderly subjects. Rmax, Rz, and Ra should be preferred for measuring skin surface topography with PRIMOS.
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Affiliation(s)
- C Trojahn
- Department of Dermatology and Allergy, Clinical Research Center for Hair and Skin Science, Charité-Universitätsmedizin Berlin, Berlin, Germany
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Kochhar JS, Quek TC, Soon WJ, Choi J, Zou S, Kang L. Effect of Microneedle Geometry and Supporting Substrate on Microneedle Array Penetration into Skin. J Pharm Sci 2013; 102:4100-8. [DOI: 10.1002/jps.23724] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Revised: 08/09/2013] [Accepted: 08/15/2013] [Indexed: 11/08/2022]
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