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Suhail A, Banerjee A, Rajesh R. Dissipation and recovery in collagen fibrils under cyclic loading: A molecular dynamics study. Phys Rev E 2024; 109:024411. [PMID: 38491641 DOI: 10.1103/physreve.109.024411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 01/22/2024] [Indexed: 03/18/2024]
Abstract
The hysteretic behavior exhibited by collagen fibrils, when subjected to cyclic loading, is known to result in both dissipation as well as accumulation of residual strain. On subsequent relaxation, partial recovery has also been reported. Cross-links have been considered to play a key role in overall mechanical properties. Here, we modify an existing coarse-grained molecular dynamics model for collagen fibril with initially cross-linked collagen molecules, which is known to reproduce the response to uniaxial strain, by incorporating reformation of cross-links to allow for possible recovery of the fibril. Using molecular dynamics simulations, we show that our model successfully replicates the key features observed in experimental data, including the movement of hysteresis loops, the time evolution of residual strains and energy dissipation, as well as the recovery observed during relaxation. We also show that the characteristic cycle number, describing the approach toward steady state, has a value similar to that in experiments. We also emphasize the vital role of the degree of cross-linking on the key features of the macroscopic response to cyclic loading.
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Affiliation(s)
- Amir Suhail
- The Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai 600113, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India
| | | | - R Rajesh
- The Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai 600113, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India
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Khattignavong E, Neshatian M, Vaez M, Guillermin A, Tauer JT, Odlyha M, Mittal N, Komarova SV, Zahouani H, Bozec L. Development of a facile method to compute collagen network pathological anisotropy using AFM imaging. Sci Rep 2023; 13:20173. [PMID: 37978303 PMCID: PMC10656449 DOI: 10.1038/s41598-023-47350-y] [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: 03/20/2023] [Accepted: 11/12/2023] [Indexed: 11/19/2023] Open
Abstract
Type I collagen, a fundamental extracellular matrix (ECM) component, is pivotal in maintaining tissue integrity and strength. It is also the most prevalent fibrous biopolymer within the ECM, ubiquitous in mammalian organisms. This structural protein provides essential mechanical stability and resilience to various tissues, including tendons, ligaments, skin, bone, and dentin. Collagen has been structurally investigated for several decades, and variation to its ultrastructure by histology has been associated with several pathological conditions. The current study addresses a critical challenge in the field of collagen research by providing a novel method for studying collagen fibril morphology at the nanoscale. It offers a computational approach to quantifying collagen properties, enabling a deeper understanding of how collagen type I can be affected by pathological conditions. The application of Fast Fourier Transform (FFT) coupled with Atomic Force Microscope (AFM) imaging distinguishes not only healthy and diseased skin but also holds potential for automated diagnosis of connective tissue disorders (CTDs), contributing to both clinical diagnostics and fundamental research in this area. Here we studied the changes in the structural parameters of collagen fibrils in Ehlers Danlos Syndrome (EDS). We have used skin extracted from genetically mutant mice that exhibit EDS phenotype as our model system (Col1a1Jrt/+ mice). The collagen fibrils were analyzed by AFM based descriptive-structural parameters, coupled with a 2D Fast Fourier Transform(2D-FFT) approach that automated the analysis of AFM images. In addition, each sample was characterized based on its FFT and power spectral density. Our qualitative data showed morphological differences in collagen fibril clarity (clearness of the collagen fibril edge with their neighbouring fibri), D-banding, orientation, and linearity. We have also demonstrated that FFT could be a new tool for distinguishing healthy from tissues with CTDs by measuring the disorganization of fibrils in the matrix. We have also employed FFT to reveal the orientations of the collagen fibrils, providing clinically relevant phenotypic information on their organization and anisotropy. The result of this study can be used to develop a new automated tool for better diagnosis of CTDs.
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Affiliation(s)
- Emilie Khattignavong
- Faculty of Dentistry, University of Toronto, 124 Edward Street, Toronto, ON, M5G 1G6, Canada
- UMR 5513, Laboratoire de Tribologie et Dynamique Des Systémes, École Centrale de Lyon-École Nationale d'Ingénieurs de Saint, Université de Lyon, Étienne, France
| | - Mehrnoosh Neshatian
- Faculty of Dentistry, University of Toronto, 124 Edward Street, Toronto, ON, M5G 1G6, Canada
| | - Mina Vaez
- Faculty of Dentistry, University of Toronto, 124 Edward Street, Toronto, ON, M5G 1G6, Canada
| | - Amaury Guillermin
- UMR 5513, Laboratoire de Tribologie et Dynamique Des Systémes, École Centrale de Lyon-École Nationale d'Ingénieurs de Saint, Université de Lyon, Étienne, France
| | - Josephine T Tauer
- Shriners Hospital for Children, Montreal, QC, Canada
- Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
| | - Marianne Odlyha
- School of Biological Science, Birkbeck College, University of London, London, UK
| | - Nimish Mittal
- Division of Physical Medicine and Rehabilitation, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Svetlana V Komarova
- Shriners Hospital for Children, Montreal, QC, Canada
- Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
| | - Hassan Zahouani
- UMR 5513, Laboratoire de Tribologie et Dynamique Des Systémes, École Centrale de Lyon-École Nationale d'Ingénieurs de Saint, Université de Lyon, Étienne, France
| | - Laurent Bozec
- Faculty of Dentistry, University of Toronto, 124 Edward Street, Toronto, ON, M5G 1G6, Canada.
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Czétényi A, Lakatos IÉ, Tóth B, Kiss RM. Finite element simulations of a single type I collagen fibril, using a novel cross-linking system. J Mech Behav Biomed Mater 2023; 143:105874. [PMID: 37182370 DOI: 10.1016/j.jmbbm.2023.105874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 03/29/2023] [Accepted: 04/24/2023] [Indexed: 05/16/2023]
Affiliation(s)
- András Czétényi
- Department of Mechatronics, Optics and Mechanical Engineering Informatics, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, Műegyetem rkp. 3., H-1111, Budapest, Hungary.
| | - Ilona Éva Lakatos
- Department of Structural Mechanics, Faculty of Civil Engineering, Budapest University of Technology and Economics, Műegyetem rkp. 3., H-1111, Budapest, Hungary
| | - Brigitta Tóth
- Department of Structural Mechanics, Faculty of Civil Engineering, Budapest University of Technology and Economics, Műegyetem rkp. 3., H-1111, Budapest, Hungary
| | - Rita Mária Kiss
- Department of Mechatronics, Optics and Mechanical Engineering Informatics, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, Műegyetem rkp. 3., H-1111, Budapest, Hungary
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Model Systems for Evidencing the Mediator Role of Riboflavin in the UVA Cross-Linking Treatment of Keratoconus. MOLECULES (BASEL, SWITZERLAND) 2021; 27:molecules27010190. [PMID: 35011421 PMCID: PMC8746477 DOI: 10.3390/molecules27010190] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/21/2021] [Accepted: 12/26/2021] [Indexed: 11/27/2022]
Abstract
Riboflavin under UVA radiation generates reactive oxygen species (ROS) that can induce various changes in biological systems. Under controlled conditions, these processes can be used in some treatments for ocular or dermal diseases. For instance, corneal cross-linking (CXL) treatment of keratoconus involves UVA irradiation combined with riboflavin aiming to induce the formation of new collagen fibrils in cornea. To reduce the damaging effect of ROS formed in the presence of riboflavin and UVA, the CXL treatment is performed with the addition of polysaccharides (dextran). Hyaluronic acid is a polysaccharide that can be found in the aqueous layer of the tear film. In many cases, keratoconus patients also present dry eye syndrome that can be reduced by the application of topical solutions containing hyaluronic acid. This study presents physico-chemical evidence on the effect of riboflavin on collagen fibril formation revealed by the following methods: differential scanning microcalorimetry, rheology, and STEM images. The collagen used was extracted from calf skin that contains type I collagen similar to that found in the eye. Spin trapping experiments on collagen/hyaluronic acid/riboflavin solutions evidenced the formation of ROS species by electron paramagnetic resonance measurements.
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Al Makhzoomi AK, Kirk TB, Allison GT. An AFM study of the nanostructural response of New Zealand white rabbit Achilles tendons to cyclic loading. Microsc Res Tech 2021; 85:728-737. [PMID: 34632676 DOI: 10.1002/jemt.23944] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/14/2021] [Accepted: 09/09/2021] [Indexed: 01/21/2023]
Abstract
The nanostructural response of New Zealand white rabbit Achilles tendons to a fatigue damage model was assessed quantitatively and qualitatively using the endpoint of dose assessments of each tendon from our previous study. The change in mechanical properties was assessed concurrently with nanostructural change in the same non-viable intact tendon. Atomic force microscopy was used to study the elongation of D-periodicities, and the changes were compared both within the same fibril bundle and between fibril bundles. D-periodicities increased due to both increased strain and increasing numbers of fatigue cycles. Although no significant difference in D-periodicity lengthening was found between fibril bundles, the lengthening of D-periodicity correlated strongly with the overall tendon mechanical changes. The accurate quantification of fibril elongation in response to macroscopic applied strain assisted in assessing the complex structure-function relationship in Achilles tendons.
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Affiliation(s)
- Anas K Al Makhzoomi
- School of Allied Health, Faculty of Health Science, Curtin University, Perth, Western Australia, Australia
| | - Thomas B Kirk
- School of Science, Engineering and Technology, RMIT University Vietnam, Ho Chi Minh City, Vietnam
| | - Garry T Allison
- Associate Deputy Vice-Chancellor, Research Excellence, Curtin University, Perth, Western Australia, Australia
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Al Makhzoomi AK, Kirk TB, Dye DE, Allison GT. The influence of glycosaminoglycan proteoglycan side chains on tensile force transmission and the nanostructural properties of Achilles tendons. Microsc Res Tech 2021; 85:233-243. [PMID: 34390286 DOI: 10.1002/jemt.23899] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 07/16/2021] [Accepted: 07/25/2021] [Indexed: 01/13/2023]
Abstract
This study investigates the nanostructural mechanisms that lie behind load transmission in tendons and the role of glycosaminoglycans (GAGs) in the transmission of force in the tendon extracellular matrix. The GAGs in white New Zealand rabbit Achilles tendons were enzymatically depleted, and the tendons subjected to cyclic loading at 6% strain for up to 2 hr. A nanoscale morphometric assessment of fibril deformation under strain was linked with the decline in the tendon macroscale mechanical properties. An atomic force microscope (AFM) was employed to characterize the D-periodicity within and between fibril bundles (WFB and BFB, respectively). By the end of the second hour of the applied strain, the WFB and BFB D-periodicities had significantly increased in the GAG-depleted group (29% increase compared with 15% for the control, p < .0001). No statistically significant differences were found between WFB and BFB D-periodicities in either the control or GAG-depleted groups, suggesting that mechanical load in Achilles tendons is uniformly distributed and fairly homogenous among the WFB and BFB networks. The results of this study have provided evidence of a cycle-dependent mechanism of damage accumulation. The accurate quantification of fibril elongation (measured as the WFB and BFB D-periodicity lengths) in response to macroscopic applied strain has assisted in assessing the complex structure-function relationship in Achilles tendon.
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Affiliation(s)
- Anas K Al Makhzoomi
- School of Allied Health, Faculty of Health Science, Curtin University, Perth, Western Australia, Australia
| | - Thomas B Kirk
- Dean, School of Science, Engineering and Technology, RMIT University Vietnam, Ho Chi Minh City, Vietnam
| | - Danielle E Dye
- Curtin Medical School, Faculty of Health Sciences, Curtin University, Perth, Western Australia, Australia
| | - Garry T Allison
- Associate Deputy Vice-Chancellor -Research Excellence - Curtin University, Perth, Western Australia, Australia, Member Board of Directors; Sports Medicine Australia, Perth
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Romero-Castillo I, López-Ruiz E, Fernández-Sánchez JF, Marchal JA, Gómez-Morales J. Self-Assembled Type I Collagen-Apatite Fibers with Varying Mineralization Extent and Luminescent Terbium Promote Osteogenic Differentiation of Mesenchymal Stem Cells. Macromol Biosci 2020; 21:e2000319. [PMID: 33369064 DOI: 10.1002/mabi.202000319] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 11/27/2020] [Indexed: 11/10/2022]
Abstract
This work explores in depth the simultaneous self-assembly and mineralization of type I collagen by a base-acid neutralization technique to prepare biomimetic collagen-apatite fibrils with varying mineralization extent and doped with luminescent bactericidal Tb3+ ions. Two variants of the method are tested: base-acid titration, a solution of Ca(OH)2 is added dropwise to a stirred solution containing type I collagen dispersed in H3 PO4 ; and direct mixing, the Ca(OH)2 solution is added by fast dripping onto the acidic solution. Only the direct mixing variant yielded an effective control of calcium phosphate polymorphism. Luminescence spectroscopy reveals the long luminescence lifetime and high relative luminescence intensity of the Tb3+ -doped materials, while two-photon confocal fluorescence microscopy shows the characteristic green fluorescence light when using excitation wavelength of 458 nm, which is not harmful to bone tissue. Cytotoxicity/viability tests reveal that direct mixing samples show higher cell proliferation than titration samples. Additionally, osteogenic differentiation essays show that all mineralized fibrils promote the osteogenic differentiation, but the effect is more pronounced when using samples prepared by direct mixing, and more notably when using the Tb3+ -doped mineralized fibrils. Based on these findings it is concluded that the new nanocomposite is an ideal candidate for bone regenerative therapy.
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Affiliation(s)
- Ismael Romero-Castillo
- Laboratorio de Estudios Cristalográficos, IACT-CSIC-UGR, Avda. Las Palmeras, no. 4, Armilla, Granada, E-18100, Spain
| | - Elena López-Ruiz
- Instituto de Investigación Biosanitaria ibs. Granada, University of Granada, Granada, E-18014, Spain.,Biopathology and Regenerative Medicine Institute (IBIMER), Centre for Biomedical Research, University of Granada, Granada, E-18100, Spain.,Excellence Research Unit "Modelling Nature" (MNat), University of Granada, Granada, E-18071, Spain.,Department of Health Science, Faculty of Experimental Science, University of Jaén, Jaén, E-23071, Spain
| | | | - Juan Antonio Marchal
- Instituto de Investigación Biosanitaria ibs. Granada, University of Granada, Granada, E-18014, Spain.,Biopathology and Regenerative Medicine Institute (IBIMER), Centre for Biomedical Research, University of Granada, Granada, E-18100, Spain.,Excellence Research Unit "Modelling Nature" (MNat), University of Granada, Granada, E-18071, Spain
| | - Jaime Gómez-Morales
- Laboratorio de Estudios Cristalográficos, IACT-CSIC-UGR, Avda. Las Palmeras, no. 4, Armilla, Granada, E-18100, Spain
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Cauble MA, Muckley MJ, Fang M, Fessler JA, Welch K, Rothman ED, Orr BG, Duong LT, Holl MMB. Estrogen depletion and drug treatment alter the microstructure of type I collagen in bone. Bone Rep 2016; 5:243-251. [PMID: 28580393 PMCID: PMC5440968 DOI: 10.1016/j.bonr.2016.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 08/15/2016] [Accepted: 08/25/2016] [Indexed: 12/22/2022] Open
Abstract
The impact of estrogen depletion and drug treatment on type I collagen fibril nanomorphology and collagen fibril packing (microstructure) was evaluated by atomic force microscopy (AFM) using an ovariectomized (OVX) rabbit model of estrogen deficiency induced bone loss. Nine month-old New Zealand white female rabbits were treated as follows: sham-operated (Sham; n = 11), OVX + vehicle (OVX + Veh; n = 12), OVX + alendronate (ALN, 600 μg/kg/wk., s.c.; n = 12), and OVX + cathepsin-K inhibitor L-235 (CatKI, 10 mg/kg, daily, p.o.; n = 13) in prevention mode for 27 weeks. Samples from the cortical femur and trabecular lumbar vertebrae were polished, demineralized, and imaged using AFM. Auto-correlation of image patches was used to generate a vector field for each image that mathematically approximated the collagen fibril alignment. This vector field was used to compute an information-theoretic entropy that was employed as a quantitative fibril alignment parameter (FAP) to allow image-to-image and sample-to-sample comparison. For all samples, no change was observed in the average FAP values; however significant differences in the distribution of FAP values were observed. In particular, OVX + Veh lumbar vertebrae samples contained a tail of lower FAP values representing regions of greater fibril alignment. OVX + ALN treatment resulted in a FAP distribution with a tail indicating greater alignment for cortical femur and less alignment for trabecular lumbar vertebrae. OVX + CatKI treatment gave a distribution of FAP values with a tail indicating less alignment for cortical femur and no change for trabecular lumbar vertebrae. Fibril alignment was also evaluated by considering when a fibril was part of discrete bundles or sheets (classified as parallel) or not (classified as oblique). For this analysis, the percentage of parallel fibrils in cortical femur for the OVX group was 17% lower than the Sham group. OVX + ALN treatment partially prevented the proportion of parallel fibrils from decreasing and OVX + CatKI treatment completely prevented a change. In trabecular lumbar vertebrae, there was no difference in the percentage of parallel fibrils between Sham and any of the other treatment groups.
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Affiliation(s)
- Meagan A. Cauble
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Matthew J. Muckley
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Ming Fang
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Jeffrey A. Fessler
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
- Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, USA
| | - Kathleen Welch
- Center for Statistical Consultation and Research (CSCAR), University of Michigan, Ann Arbor, MI, USA
| | - Edward D. Rothman
- Center for Statistical Consultation and Research (CSCAR), University of Michigan, Ann Arbor, MI, USA
- Department of Statistics, University of Michigan, Ann Arbor, MI, USA
| | - Bradford G. Orr
- Department of Physics, University of Michigan, Ann Arbor, MI, USA
| | - Le T. Duong
- Bone Biology Group, Merck Research Laboratories, West Point, PA, USA
| | - Mark M. Banaszak Holl
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
- Macromolecular Science and Engineering, University of Michigan, Ann Arbor, MI, USA
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Kreplak L. Introduction to Atomic Force Microscopy (AFM) in Biology. ACTA ACUST UNITED AC 2016; 85:17.7.1-17.7.21. [PMID: 27479503 DOI: 10.1002/cpps.14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The atomic force microscope (AFM) has the unique capability of imaging biological samples with molecular resolution in buffer solution over a wide range of time scales from milliseconds to hours. In addition to providing topographical images of surfaces with nanometer- to angstrom-scale resolution, forces between single molecules and mechanical properties of biological samples can be investigated from the nano-scale to the micro-scale. Importantly, the measurements are made in buffer solutions, allowing biological samples to "stay alive" within a physiological-like environment while temporal changes in structure are measured-e.g., before and after addition of chemical reagents. These qualities distinguish AFM from conventional imaging techniques of comparable resolution, e.g., electron microscopy (EM). This unit provides an introduction to AFM on biological systems and describes specific examples of AFM on proteins, cells, and tissues. The physical principles of the technique and methodological aspects of its practical use and applications are also described. © 2016 by John Wiley & Sons, Inc.
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Affiliation(s)
- Laurent Kreplak
- Department of Physics & Atmospheric Science, Dalhousie University, Halifax, Canada
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Su HN, Xie BB. Reply to the comment on "The ultrastructure of type I collagen at nanoscale: large or small D-spacing distribution?" by J. Wallace, Nanoscale, 2015, 7, DOI: 10.1039/c4nr03160a. NANOSCALE 2015; 7:1235-1236. [PMID: 25473806 DOI: 10.1039/c4nr05120c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Measuring D-spacing values from collagen fibrils or collagen fascicles with surface curvatures will introduce additional errors. This error might be minimized by studying single collagen fibrils which are parallel to the surface of substrates.
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Affiliation(s)
- Hai-Nan Su
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, China.
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Wallace JM. Comment on "The ultrastructure of type I collagen at nanoscale: large or small D-spacing distribution?" by H.-N. Su, L.-Y. Ran, Z.-H. Chen, Q.-L. Qin, M. Shi, X.-Y. Song, X.-L. Chen, Y.-Z. Zhang and B.-B. Xie, Nanoscale, 2014, 6, 8134. NANOSCALE 2015; 7:1233-1234. [PMID: 25418951 DOI: 10.1039/c4nr03160a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Type I collagen D-spacing and its distribution may be a window into the nanoscale state of tissues.
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Affiliation(s)
- Joseph M Wallace
- Department of Biomedical Engineering, Indiana University-Purdue University Indianapolis, Department of Orthopaedic Surgery (adjunct), Indiana University School of Medicine, USA.
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