1
|
Rhode M, Harms O, Finck Y, Dautzenberg P, Schweizer J, Lüpke M, Freise F, Fehr M. Performing a Three-Dimensional Finite Element Analysis (FEA) to Simulate and Quantify the Contact Pressure in the Canine Elbow Joint: A Pilot Study. Vet Comp Orthop Traumatol 2022; 35:279-288. [PMID: 35785818 DOI: 10.1055/s-0042-1748876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
OBJECTIVE The aim of this study was to measure surface pressures and force distribution on radius and ulna in healthy and dysplastic elbow joints in different positions using the finite element analysis (FEA). STUDY DESIGN FEA was performed on computed tomographic data of healthy and fragmented coronoid process diseased elbow joints of Labrador Retrievers. It considered the articular cartilage, collateral ligaments, triceps and biceps muscle. The analysis of each joint was performed in four positions (standing position: 145 degrees and three positions of the stance phase of gait: beginning: 115 degrees, middle: 110 degrees, end: 145 degrees joint angle) in consideration of different ground reaction forces (standing: 88.3 N; stance phase of gait: 182.5 N). RESULTS Mean values of total force of 317.5 N (standing), 590.7 N (beginning), 330.9 N (middle) and 730.9 N (end) were measured. The percentual force distribution resulted in a total of 49.56 ± 26.58% on the ulna with a very inhomogeneous distribution. A significant difference was detected between the positions 'standing' and 'end' (p = 0.0497) regardless of the joint condition. In some FEA results, visual assessment of the surface pressures indicated an increase in pressure in the region of the medial compartment without a uniform pattern. An increase in pressure resulted in an area increase in the pressure marks on the joint surface and measurable pressure was increased at a larger joint angle. CLINICAL SIGNIFICANCE FEA can provide information about the transmission of force in the joint. Prior to the use of FEA in scientific clinical research for the simulation of force, further model improvements are necessary.
Collapse
Affiliation(s)
- Michaela Rhode
- Clinic for Small Animal Medicine, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Oliver Harms
- Clinic for Small Animal Medicine, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | | | - Philipp Dautzenberg
- Clinic for Small Animal Medicine, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Julia Schweizer
- Veterinary Practice for Small Animal Surgery, Neuenrade, Germany
| | - Matthias Lüpke
- Institute for General Radiology and Medical Physics, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Fritjof Freise
- Institute for Biometry, Epidemiology and Information Processing, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Michael Fehr
- Clinic for Small Mammals, Reptiles and Birds, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| |
Collapse
|
2
|
Silver FH, Kelkar N, Deshmukh T. Use of vibrational optical coherence tomography to measure viscoelastic properties of muscle and tendon: A new method to follow musculoskeletal injury and pathology In vivo. J Mech Behav Biomed Mater 2021; 119:104479. [PMID: 33798938 DOI: 10.1016/j.jmbbm.2021.104479] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 02/26/2021] [Accepted: 03/15/2021] [Indexed: 12/17/2022]
Abstract
The biomechanical properties of muscles and tendons in vivo are important parameters needed to understand musculoskeletal physiology and pathology. Values of the shear moduli reported for human musculoskeletal components using elastographic techniques range from several KPa to about 100 KPa and are much lower than the tensile moduli measured in vivo which are reported to be as high as several hundred MPa at high strains. In this paper we report the results of a pilot study to measure the mechanical properties of human muscles and tendons non-invasively and non-destructively in vivo using vibrational optical coherence tomography (VOCT). VOCT is a non-invasive technique that uses audible sound and reflected infrared light to measure the resonant frequency of each tissue component. Using VOCT we report that the moduli at the biceps muscle-tendon junction are about 24-30 MPa even though moduli in other anatomic locations of muscle and tendons can vary by as much as 10 MPa. It is concluded that the modulus and stress exerted by tendons and muscles at the muscle-tendon junction are similar and that deposition of fibrous tissue at the junction will lead to reduced values of the modulus leading to tissue pathology and muscle injury.
Collapse
Affiliation(s)
- Frederick H Silver
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA; OptoVibronex, LLC., Allentown, Pa, USA.
| | | | | |
Collapse
|
3
|
Horner CB, Maldonado M, Tai Y, Rony RMIK, Nam J. Spatially Regulated Multiphenotypic Differentiation of Stem Cells in 3D via Engineered Mechanical Gradient. ACS APPLIED MATERIALS & INTERFACES 2019; 11:45479-45488. [PMID: 31714732 DOI: 10.1021/acsami.9b17266] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Within the osteochondral interface, cellular and extracellular matrix gradients provide a biomechanical and biochemical niche for homeostatic tissue functions. Postnatal joint loading is critical for the development of such tissue gradients, leading to the formation of functional osteochondral tissues composed of superficial, middle, and deep zones of cartilage, and underlying subchondral bone, in a depth-dependent manner. In this regard, a novel, variable core-shell electrospinning strategy was employed to generate spatially controlled strain gradients within three-dimensional scaffolds under dynamic compressive loading, enabling the local strain-magnitude dependent, multiphenotypic stem cell differentiation. Human mesenchymal stem cells (hMSCs) were cultured in electrospun scaffolds with a linear or biphasic mechanical gradient, which was computationally engineered and experimentally validated. The cell/scaffold constructs were subjected to various magnitudes of dynamic compressive strains in a scaffold depth-dependent manner at a frequency of 1 Hz for 2 h daily for up to 42 days in osteogenic media. Spatially upregulated gene expression of chondrogenic markers (ACAN, COL2A1, PRG4) and glycosaminoglycan deposition was observed in the areas of greater compressive strains. In contrast, osteogenic markers (COL1A1, SPARC, RUNX2) and calcium deposition were downregulated in response to high local compressive strains. Dynamic mechanical analysis showed the maintenance of the engineered mechanical gradients only under dynamic culture conditions, confirming the potent role of biomechanical gradients in developing and maintaining a tissue gradient. These results demonstrate that multiphenotypic differentiation of hMSCs can be controlled by regulating local mechanical microenvironments, providing a novel strategy to recapitulate the gradient structure in osteochondral tissues for successful regeneration of damaged joints in vivo and facile development of interfacial tissue models in vitro.
Collapse
Affiliation(s)
- Christopher B Horner
- Department of Bioengineering , University of California , Riverside , California 92521 , United States
| | - Maricela Maldonado
- Department of Bioengineering , University of California , Riverside , California 92521 , United States
| | - Youyi Tai
- Department of Bioengineering , University of California , Riverside , California 92521 , United States
| | - R M Imtiaz Karim Rony
- Department of Bioengineering , University of California , Riverside , California 92521 , United States
| | - Jin Nam
- Department of Bioengineering , University of California , Riverside , California 92521 , United States
| |
Collapse
|
4
|
Gao LL, Lin XL, Liu DD, Chen L, Zhang CQ, Gao H. Depth-dependent ratcheting strains of young and adult articular cartilages by experiments and predictions. Biomed Eng Online 2019; 18:85. [PMID: 31362738 PMCID: PMC6668180 DOI: 10.1186/s12938-019-0705-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 07/23/2019] [Indexed: 11/24/2022] Open
Abstract
Background Ratcheting strain is produced due to the repeated accumulation of compressive strain in cartilage and may be a precursor to osteoarthritis. The aim of this study was to investigate the ratcheting behaviors of young and adult articular cartilages under cyclic compression by experiments and theoretical predictions. Methods A series of uniaxial cyclic compression tests were conducted for young and adult cartilage, and the effects of different loading conditions on their ratcheting behaviors were probed. A theoretical ratcheting model was constructed and applied to predict the ratcheting strains of young and adult cartilages with different loading conditions. Results Ratcheting strains of young and adult cartilages rapidly increased at the initial stage, followed by a slower increase in subsequent stages. The strain accumulation value and its rate for young cartilage were greater than them for adult cartilage. The ratcheting strains of the two groups of cartilage samples decreased with increasing stress rate, while they increased with increasing stress amplitude. As the stress amplitude increased, the gap between the ratcheting strains of young and adult cartilages increased gradually. The ratcheting strains of young and adult cartilages decreased along the cartilage depth from the surface to the deep layer. The ratcheting strains of different layers increased with the compressive cycle, and the difference among the three layers was noticeable. Additionally, the theoretical predictions agreed with the experimental data. Conclusions Overall, the ratcheting behavior of articular cartilage is affected by the degree of articular cartilage maturation.
Collapse
Affiliation(s)
- Li-Lan Gao
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, China. .,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education (Tianjin University of Technology), Tianjin, China.
| | - Xiang-Long Lin
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education (Tianjin University of Technology), Tianjin, China
| | - Dong-Dong Liu
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education (Tianjin University of Technology), Tianjin, China
| | - Ling Chen
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, China. .,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education (Tianjin University of Technology), Tianjin, China.
| | - Chun-Qiu Zhang
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education (Tianjin University of Technology), Tianjin, China
| | - Hong Gao
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| |
Collapse
|
5
|
Ribitsch I, Mayer RL, Egerbacher M, Gabner S, Kańduła MM, Rosser J, Haltmayer E, Auer U, Gültekin S, Huber J, Bileck A, Kreil DP, Gerner C, Jenner F. Fetal articular cartilage regeneration versus adult fibrocartilaginous repair: secretome proteomics unravels molecular mechanisms in an ovine model. Dis Model Mech 2018; 11:11/7/dmm033092. [PMID: 29991479 PMCID: PMC6078409 DOI: 10.1242/dmm.033092] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 05/18/2018] [Indexed: 12/27/2022] Open
Abstract
Osteoarthritis (OA), a degenerative joint disease characterized by progressive cartilage degeneration, is one of the leading causes of disability worldwide owing to the limited regenerative capacity of adult articular cartilage. Currently, there are no disease-modifying pharmacological or surgical therapies for OA. Fetal mammals, in contrast to adults, are capable of regenerating injured cartilage in the first two trimesters of gestation. A deeper understanding of the properties intrinsic to the response of fetal tissue to injury would allow us to modulate the way in which adult tissue responds to injury. In this study, we employed secretome proteomics to compare fetal and adult protein regulation in response to cartilage injury using an ovine cartilage defect model. The most relevant events comprised proteins associated with the immune response and inflammation, proteins specific for cartilage tissue and cartilage development, and proteins involved in cell growth and proliferation. Alarmins S100A8, S100A9 and S100A12 and coiled-coil domain containing 88A (CCDC88A), which are associated with inflammatory processes, were found to be significantly upregulated following injury in adult, but not in fetal animals. By contrast, cartilage-specific proteins like proteoglycan 4 were upregulated in response to injury only in fetal sheep postinjury. Our results demonstrate the power and relevance of the ovine fetal cartilage regeneration model presented here for the first time. The identification of previously unrecognized modulatory proteins that plausibly affect the healing process holds great promise for potential therapeutic interventions. Summary: Secretome proteomics identifies differential regulation of inflammation modulators during fetal and adult articular cartilage defect healing, offering novel strategies for therapy.
Collapse
Affiliation(s)
- Iris Ribitsch
- VETERM, University Equine Hospital, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Rupert L Mayer
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Vienna 1090, Austria
| | - Monika Egerbacher
- Histology & Embryology, Department of Pathobiology, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Simone Gabner
- Histology & Embryology, Department of Pathobiology, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Maciej M Kańduła
- Department of Biotechnology, Boku University Vienna, Vienna 1180, Austria.,Institute of Bioinformatics, Johannes Kepler University, Linz 4040, Austria
| | - Julie Rosser
- VETERM, University Equine Hospital, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Eva Haltmayer
- VETERM, University Equine Hospital, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Ulrike Auer
- Department of Companion Animals and Horses, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Sinan Gültekin
- VETERM, University Equine Hospital, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Johann Huber
- Teaching and Research Farm Kremesberg, Clinical Unit for Herd Health Management in Ruminants, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Andrea Bileck
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Vienna 1090, Austria
| | - David P Kreil
- Department of Biotechnology, Boku University Vienna, Vienna 1180, Austria
| | - Christopher Gerner
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Vienna 1090, Austria
| | - Florien Jenner
- VETERM, University Equine Hospital, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| |
Collapse
|
6
|
Hellings IR, Dolvik NI, Ekman S, Olstad K. Cartilage canals in the distal intermediate ridge of the tibia of fetuses and foals are surrounded by different types of collagen. J Anat 2017. [PMID: 28620929 PMCID: PMC5603784 DOI: 10.1111/joa.12650] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Some epiphyseal growth cartilage canals are surrounded by a ring of hypereosinophilic matrix consisting of collagen type I. Absence of the collagen type I ring may predispose canal vessels to failure and osteochondrosis, which can lead to fragments in joints (osteochondrosis dissecans). It is not known whether the ring develops in response to programming or biomechanical force. The distribution that may reveal the function of the ring has only been described in the distal femur of a limited number of foals. It is also not known which cells are responsible for producing the collagen ring. The aims of the current study were to examine fetuses and foals to infer whether the ring forms in response to biomechanical force or programming, to describe distribution and to investigate which cell type produces the ring. The material consisted of 46 fetuses and foals from 293 days of gestation to 142 days old, of both sexes and different breeds, divided into three groups, designated the naïve group up to and including the day of birth, the adapting group from 2 days up to and including 14 days old, and the loaded group from 15 days and older. The distal tibia was sawn into parasagittal slabs and the cranial half of the central slab from the intermediate ridge was examined by light microscopy and immunohistochemical staining for collagen type I. Presence, completeness and location of the collagen ring was compared, as was the quantity of perivascular mesenchymal cells. An eosinophilic ring present on HE-stained sections was seen in every single fetus and foal examined, which corresponded to collagen type I in immunostained sections. A higher proportion of cartilage canals were surrounded by an eosinophilic ring in the naïve and adapting groups at 73 and 76%, respectively, compared with the loaded group at 51%. When considering only patent canals, the proportion of canals with an eosinophilic ring was higher in the adapting and loaded than the naïve group of foals. The ring was present around 90 and 81% of patent canals in the deep and middle layers, respectively, compared with 58% in the superficial layer, and the ring was more often complete around deep compared with superficial canals. The ring was absent or partial around chondrifying canals. When an eosinophilic ring was present around patent canals, it was more common for the canal to contain one or more layers of perivascular mesenchymal cells rather than few to no layers. It was also more common for the collagen ring to be more complete around canals that contained many as opposed to few mesenchymal cells. In conclusion, the proportion of cartilage canals that had an eosinophilic ring was similar in all three groups of fetuses and foals, indicating that the presence of the collagen ring was mostly programmed, although some adaptation was evident. The ring was more often present around deep, compared with superficial canals, indicating a role in preparation for ossification. The collagen ring appeared to be produced by perivascular mesenchymal cells.
Collapse
Affiliation(s)
- Ingunn Risnes Hellings
- Faculty of Veterinary Medicine and Biosciences, Department of Companion Animal Clinical Sciences, Equine Section, Norwegian University of Life Sciences, Oslo, Norway
| | - Nils Ivar Dolvik
- Faculty of Veterinary Medicine and Biosciences, Department of Companion Animal Clinical Sciences, Equine Section, Norwegian University of Life Sciences, Oslo, Norway
| | - Stina Ekman
- Department of Biomedical Sciences and Veterinary Public Health, Section of Pathology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Kristin Olstad
- Faculty of Veterinary Medicine and Biosciences, Department of Companion Animal Clinical Sciences, Equine Section, Norwegian University of Life Sciences, Oslo, Norway
| |
Collapse
|
7
|
Finnøy A, Olstad K, Lilledahl MB. Second harmonic generation imaging reveals a distinct organization of collagen fibrils in locations associated with cartilage growth. Connect Tissue Res 2016; 57:374-87. [PMID: 27215664 DOI: 10.1080/03008207.2016.1190348] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PURPOSE The articular-epiphyseal cartilage complex (AECC) is responsible for the expansion of the bone ends and serves the function of the articular cartilage in juvenile mammals. Bundles of collagen fibrils surrounding cells were in the literature observed more frequently near the articular surface of the AECC. The articular surface, the perichondrium, and cartilage canals are interfaces where appositional growth of the AECC has been demonstrated. The current study aimed to evaluate the potential of second harmonic generation (SHG) to locate the collagen fibril bundles near the articular surface and to examine whether a comparable collagen fibril organization could be observed near the other interfaces of the AECC. MATERIALS AND METHODS The study included the femoral condyle of four piglets aged 82-141 days. The forward and backward scattered SHG, and their ratio, was analyzed across the AECC using objectives with different numerical aperture. Two-photon-excited fluorescence was used to visualize cells. RESULTS A similar pattern of collagen fibril organization was observed near the articular surface, around cartilage canals, and adjacent to the perichondrium. The pattern consisted of a higher ratio of forward to backward scattered SHG that increased relative to the surrounding matrix at lower numerical aperture. This was interpreted to reflect collagen fibril bundles in the territorial matrix of cells in these areas. CONCLUSIONS The observed arrangement of collagen fibrils was suggested to be related to the presumed different growth activity in these areas and indicated that SHG may be used as an indirect and label-free marker for cartilage matrix growth.
Collapse
Affiliation(s)
- Andreas Finnøy
- a Department of Physics , Norwegian University of Science and Technology (NTNU) , Trondheim , Norway
| | - Kristin Olstad
- b Norwegian University of Life Sciences, Faculty of Veterinary Medicine and Biosciences , Oslo , Norway
| | - Magnus B Lilledahl
- a Department of Physics , Norwegian University of Science and Technology (NTNU) , Trondheim , Norway
| |
Collapse
|
8
|
Wirth W, Eckstein F, Boeth H, Diederichs G, Hudelmaier M, Duda GN. Longitudinal analysis of MR spin-spin relaxation times (T2) in medial femorotibial cartilage of adolescent vs mature athletes: dependence of deep and superficial zone properties on sex and age. Osteoarthritis Cartilage 2014; 22:1554-8. [PMID: 25278064 DOI: 10.1016/j.joca.2014.06.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 05/30/2014] [Accepted: 06/03/2014] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Cartilage spin-spin magnetic resonance imaging (MRI) relaxation time (T2) represents a promising imaging biomarker of "early" osteoarthritis (OA) known to be associated with cartilage composition (collagen integrity, orientation, and hydration). However, no longitudinal imaging studies have been conducted to examine cartilage maturation in healthy subjects thus far. Therefore, we explore T2 change in the deep and superficial cartilage layers at the end of adolescence. METHODS Twenty adolescent and 20 mature volleyball athletes were studied (each 10 men and 10 women). Multi-echo spin-echo (MESE) images were acquired at baseline and 2-year follow-up. After segmentation, cartilage T2 was calculated in the deep and superficial cartilage layers of the medial tibial (MT) and the central, weight-bearing part of the medial femoral condyle (cMF), using five echoes (TE 19.4-58.2 ms). RESULTS 16 adolescent (6 men, 10 women, baseline age 15.8 ± 0.5 years) and 17 mature (nine men, eight women, age 46.5 ± 5.2 years) athletes had complete baseline and follow-up images of sufficient quality to compute T2. In adolescents, a longitudinal decrease in T2 was observed in the deep layers of MT (-2.0 ms; 95% confidence interval (CI): [-3.4, -0.6] ms; P < 0.01) and cMF (-1.3 ms; [-2.4, -0.3] ms; P < 0.05), without obvious differences between males and females. No significant change was observed in the superficial layers, or in the deep or superficial layers of the mature athletes. CONCLUSION In this first pilot study on quantitative imaging of cartilage maturation in healthy, athletic subjects, we find evidence of cartilage compositional change in deep cartilage layers of the medial femorotibial compartment in adolescents, most likely related to organizational changes in the collagen matrix.
Collapse
Affiliation(s)
- W Wirth
- Institute of Anatomy, Paracelsus Medical University, Salzburg, Austria
| | - F Eckstein
- Institute of Anatomy, Paracelsus Medical University, Salzburg, Austria.
| | - H Boeth
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Center for Sports Science and Sports Medicine Berlin, Germany
| | - G Diederichs
- Department of Radiology, Charité - Universitätsmedizin Berlin, Germany
| | - M Hudelmaier
- Institute of Anatomy, Paracelsus Medical University, Salzburg, Austria
| | - G N Duda
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Center for Sports Science and Sports Medicine Berlin, Germany
| |
Collapse
|
9
|
Øien AH, Justad SR, Tenstad O, Wiig H. Effects of hydration on steric and electric charge-induced interstitial volume exclusion--a model. Biophys J 2014; 105:1276-84. [PMID: 24010671 DOI: 10.1016/j.bpj.2013.07.040] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 06/26/2013] [Accepted: 07/24/2013] [Indexed: 11/17/2022] Open
Abstract
The presence of collagen and charged macromolecules like glycosaminoglycans (GAGs) in the interstitial space limits the space available for plasma proteins and other macromolecules. This phenomenon, known as interstitial exclusion, is of importance for interstitial fluid volume regulation. Physical/mathematical models are presented for calculating the exclusion of electrically charged and neutral macromolecules that equilibrate in the interstitium under various degrees of hydration. Here, a central hypothesis is that the swelling of highly electrically charged GAGs with increased hydration shields parts of the neutral collagen of the interstitial matrix from interacting with electrically charged macromolecules, such that exclusion of charged macromolecules exhibits change due to steric and charge effects. GAGs are also thought to allow relatively small neutral, but also charged macromolecules neutralized by a very high ionic strength, diffuse into the interior of GAGs, whereas larger macromolecules may not. Thus, in the model, relatively small electrically charged macromolecules, such as human serum albumin, and larger neutral macromolecules such as IgG, will have quite similar total volume exclusion properties in the interstitium. Our results are in agreement with ex vivo and in vivo experiments, and suggest that the charge of GAGs or macromolecular drugs may be targeted to increase the tissue uptake of macromolecular therapeutic agents.
Collapse
Key Words
- 1-particles
- 2-particles
- 3-particles
- A
- A [as subscript]
- DCL(z)
- Debye length
- GAGs, glycosaminoclycans [also as subscript]
- H(z)
- L
- N1in
- O
- Q(1), Q(2)
- T
- VO
- VT
- albumin- or macromolecules in general [also as subscript]
- available
- available volume of charged particle
- available volume of small neutral macroparticle
- available volume per unit volume for large neutral macroparticles
- average volume density of macromolecules, as albumin, in cell
- axial length of equilibration cell
- charge part per unit volume of excluded volume
- circular cross-section area of equilibration cell
- collagen particles [also as subscript]
- core radius of GAG
- d1, d2 = 2H(z), d3
- dCL
- diameters of 1-, 2-, and 3-particles
- distance between two side-by-side GAGs- or collagen particle centers
- distance of closest approach in GAG-albumin interactions
- distance of closest approach in albumin-albumin interactions
- effective density of collagen particles
- electrical charge on particle I
- excluded volume per unit volume for large neutral macroparticles
- excluded volume per unit volume of charged macroparticle
- excluded volume per unit volume of small neutral macroparticle
- highest thickness value
- hydration
- inside cell tissue [also as subscript]
- l
- lowest thickness value
- n1T(z), n1O(z)
- n1in
- n2, n3
- n3eff(z)
- number densities of 2- and 3-particles
- number of macromolecules, as albumin, poured into cell
- outside cell tissue [also as subscript]
- outside tissue-cell volume
- p1
- pressure of 1-particles
- r
- radial distance
- radius of GAGs as function of tissue thickness
- rmin
- thickness of tissue sample
- tissue-cell volume
- volume density of 1-particles in tissue, outside tissue
- volume of collagen-, GAG- and macroparticle material per unit volume of tissue
- volume of water per unit volume of tissue (water content)
- z
- z1
- z2
- ζ
- λD
- νA
- νA0G
- νAO
- νE
- νE00
- νE0G
- νEO
- νH2O
- νQ
Collapse
Affiliation(s)
- Alf H Øien
- Department of Mathematics, University of Bergen, Bergen, Norway
| | | | | | | |
Collapse
|
10
|
van Riet M, Millet S, Aluwé M, Janssens G. Impact of nutrition on lameness and claw health in sows. Livest Sci 2013. [DOI: 10.1016/j.livsci.2013.06.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
11
|
|