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  1. Article: Viscoelastic Properties of Hyaluronan in Physiological Conditions.

    Cowman, Mary K / Schmidt, Tannin A / Raghavan, Preeti / Stecco, Antonio

    F1000Research

    2015  Volume 4, Page(s) 622

    Abstract: ... Newtonian flow properties. These properties affect the movement of HA-containing fluid layers within and ... Temperature can also have an effect on these properties. High viscosity can additionally affect ... Hyaluronan (HA) is a high molecular weight glycosaminoglycan of the extracellular matrix (ECM ...

    Abstract Hyaluronan (HA) is a high molecular weight glycosaminoglycan of the extracellular matrix (ECM), which is particularly abundant in soft connective tissues. Solutions of HA can be highly viscous with non-Newtonian flow properties. These properties affect the movement of HA-containing fluid layers within and underlying the deep fascia. Changes in the concentration, molecular weight, or even covalent modification of HA in inflammatory conditions, as well as changes in binding interactions with other macromolecules, can have dramatic effects on the sliding movement of fascia. The high molecular weight and the semi-flexible chain of HA are key factors leading to the high viscosity of dilute solutions, and real HA solutions show additional nonideality and greatly increased viscosity due to mutual macromolecular crowding. The shear rate dependence of the viscosity, and the viscoelasticity of HA solutions, depend on the relaxation time of the molecule, which in turn depends on the HA concentration and molecular weight. Temperature can also have an effect on these properties. High viscosity can additionally affect the lubricating function of HA solutions. Immobility can increase the concentration of HA, increase the viscosity, and reduce lubrication and gliding of the layers of connective tissue and muscle. Over time, these changes can alter both muscle structure and function. Inflammation can further increase the viscosity of HA-containing fluids if the HA is modified via covalent attachment of heavy chains derived from Inter-α-Inhibitor. Hyaluronidase hydrolyzes HA, thus reducing its molecular weight, lowering the viscosity of the extracellular matrix fluid and making outflow easier. It can also disrupt any aggregates or gel-like structures that result from HA being modified. Hyaluronidase is used medically primarily as a dispersion agent, but may also be useful in conditions where altered viscosity of the fascia is desired, such as in the treatment of muscle stiffness.
    Language English
    Publishing date 2015
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 2699932-8
    ISSN 2046-1402
    ISSN 2046-1402
    DOI 10.12688/f1000research.6885.1
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  2. Article ; Online: Viscoelastic Properties of Hyaluronan in Physiological Conditions [version 1; referees

    Mary K. Cowman / Tannin A. Schmidt / Preeti Raghavan / Antonio Stecco

    F1000Research, Vol

    2 approved]

    2015  Volume 4

    Abstract: ... Newtonian flow properties. These properties affect the movement of HA-containing fluid layers within and ... Temperature can also have an effect on these properties. High viscosity can additionally affect ... Hyaluronan (HA) is a high molecular weight glycosaminoglycan of the extracellular matrix (ECM ...

    Abstract Hyaluronan (HA) is a high molecular weight glycosaminoglycan of the extracellular matrix (ECM), which is particularly abundant in soft connective tissues. Solutions of HA can be highly viscous with non-Newtonian flow properties. These properties affect the movement of HA-containing fluid layers within and underlying the deep fascia. Changes in the concentration, molecular weight, or even covalent modification of HA in inflammatory conditions, as well as changes in binding interactions with other macromolecules, can have dramatic effects on the sliding movement of fascia. The high molecular weight and the semi-flexible chain of HA are key factors leading to the high viscosity of dilute solutions, and real HA solutions show additional nonideality and greatly increased viscosity due to mutual macromolecular crowding. The shear rate dependence of the viscosity, and the viscoelasticity of HA solutions, depend on the relaxation time of the molecule, which in turn depends on the HA concentration and molecular weight. Temperature can also have an effect on these properties. High viscosity can additionally affect the lubricating function of HA solutions. Immobility can increase the concentration of HA, increase the viscosity, and reduce lubrication and gliding of the layers of connective tissue and muscle. Over time, these changes can alter both muscle structure and function. Inflammation can further increase the viscosity of HA-containing fluids if the HA is modified via covalent attachment of heavy chains derived from Inter-α-Inhibitor. Hyaluronidase hydrolyzes HA, thus reducing its molecular weight, lowering the viscosity of the extracellular matrix fluid and making outflow easier. It can also disrupt any aggregates or gel-like structures that result from HA being modified. Hyaluronidase is used medically primarily as a dispersion agent, but may also be useful in conditions where altered viscosity of the fascia is desired, such as in the treatment of muscle stiffness.
    Keywords Muscle & Connective Tissue ; Musculoskeletal Pharmacology ; Medicine ; R ; Science ; Q
    Language English
    Publishing date 2015-08-01T00:00:00Z
    Publisher F1000 Research Ltd
    Document type Article ; Online
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  3. Article ; Online: Rheology of the vitreous gel: effects of macromolecule organization on the viscoelastic properties.

    Sharif-Kashani, Pooria / Hubschman, Jean-Pierre / Sassoon, Daniel / Kavehpour, H Pirouz

    Journal of biomechanics

    2011  Volume 44, Issue 3, Page(s) 419–423

    Abstract: The macromolecular organization of vitreous gel is responsible for its viscoelastic properties ... the role of each main component from the overall viscoelastic properties. ... Knowledge of this correlation enables us to relate the physical properties of vitreous to its pathology ...

    Abstract The macromolecular organization of vitreous gel is responsible for its viscoelastic properties. Knowledge of this correlation enables us to relate the physical properties of vitreous to its pathology, as well as optimize surgical procedures such as vitrectomy. Herein, we studied the rheological properties (e.g. dynamic deformation, shear stress-strain flow, and creep compliance) of porcine vitreous humor using a stressed-control shear rheometer. All experiments were performed in a closed environment with the temperature set to that of the human body (i.e. 37°C) to mimic in-vivo conditions. We modeled the creep deformation using the two-element retardation spectrum model. By associating each element of the model to an individual biopolymeric system in the vitreous gel, a distinct response to the applied stress was observed from each component. We hypothesized that the first viscoelastic response with the short time scale (~1 s) is associated with the collagen structure, while the second viscoelastic response with longer time scale (~100 s) is related to the microfibrilis and hyaluronan network. Consequently, we were able to differentiate the role of each main component from the overall viscoelastic properties.
    MeSH term(s) Animals ; Collagen/physiology ; Elasticity/physiology ; Extracellular Matrix/physiology ; Rheology/methods ; Stress, Mechanical ; Swine ; Viscosity ; Vitreous Body/physiology
    Chemical Substances Collagen (9007-34-5)
    Language English
    Publishing date 2011-02-03
    Publishing country United States
    Document type Journal Article
    ZDB-ID 218076-5
    ISSN 1873-2380 ; 0021-9290
    ISSN (online) 1873-2380
    ISSN 0021-9290
    DOI 10.1016/j.jbiomech.2010.10.002
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  4. Article: Role of chondroitin sulfate-hyaluronan interactions in the viscoelastic properties of extracellular matrices and fluids.

    Nishimura, M / Yan, W / Mukudai, Y / Nakamura, S / Nakamasu, K / Kawata, M / Kawamoto, T / Noshiro, M / Hamada, T / Kato, Y

    Biochimica et biophysica acta

    1997  Volume 1380, Issue 1, Page(s) 1–9

    Abstract: ... that chondroitin sulfate may play an important physiological role in determining the viscoelastic properties ... of hyaluronan mass (50-1900 kDa) under physiological conditions of pH, temperature, ionic strength and ... interactions in the viscoelastic properties of tissues and fluids, using capillary and cone-on-plate ...

    Abstract The purpose of this study was to investigate the role of chondroitin sulfate-hyaluronan interactions in the viscoelastic properties of tissues and fluids, using capillary and cone-on-plate viscometers. Chondroitin sulfate markedly increased the viscosity of hyaluronan solutions at a wide range of hyaluronan mass (50-1900 kDa) under physiological conditions of pH, temperature, ionic strength and glycosaminoglycan concentration (0.5-40 mg/ml), although the viscosity of the chondroitin sulfate solutions themselves was very low. In the assay using a cone-on-plate viscometer, chondroitin sulfate increased the viscosity of hyaluronan solutions at various shear rates. At low shear rates, the viscosity of a chondroitin sulfate (5 mg/ml)-hyaluronan (0.5 mg/ml) mixture was about 40% of that of an aggrecan (5 mg/ml)-hyaluronan (0.5 mg/ml) mixture, and at 2.8-fold higher concentrations, chondroitin sulfate elicited the same effect on the viscosity of hyaluronan solutions (5 mg/ml) as an aggrecan monomer. In the presence of oscillatory motion, the addition of aggrecan increased the elasticity (storage) modulus G' and the viscosity (loss) modulus G" of hyaluronan solutions and markedly decreased the loss tangent G"/G' at frequencies corresponding to normal joint movements. In contrast, chondroitin sulfate had only a marginal effect on the loss tangent G"/G', although it increased G' and G". These findings demonstrated that chondroitin sulfate, as well as aggrecan, increases the viscosity of hyaluronan solutions, although chondroitin sulfate has less effect on the elasticity of hyaluronan solutions than that of aggrecan, and suggest that chondroitin sulfate may play an important physiological role in determining the viscoelastic properties of extracellular matrices and fluids.
    MeSH term(s) Aggrecans ; Animals ; Chondroitin Sulfates/chemistry ; Elasticity ; Extracellular Matrix/chemistry ; Extracellular Matrix Proteins ; Extracellular Space/chemistry ; Hyaluronic Acid/chemistry ; Hydrogen-Ion Concentration ; In Vitro Techniques ; Lectins, C-Type ; Osmolar Concentration ; Proteoglycans/chemistry ; Solutions ; Temperature ; Viscosity
    Chemical Substances Aggrecans ; Extracellular Matrix Proteins ; Lectins, C-Type ; Proteoglycans ; Solutions ; Hyaluronic Acid (9004-61-9) ; Chondroitin Sulfates (9007-28-7)
    Language English
    Publishing date 1997-12-17
    Publishing country Netherlands
    Document type Comparative Study ; Journal Article
    ZDB-ID 60-7
    ISSN 1879-2596 ; 1879-260X ; 1872-8006 ; 1879-2642 ; 1879-2618 ; 1879-2650 ; 0006-3002 ; 0005-2728 ; 0005-2736 ; 0304-4165 ; 0167-4838 ; 1388-1981 ; 0167-4889 ; 0167-4781 ; 0304-419X ; 1570-9639 ; 0925-4439 ; 1874-9399
    ISSN (online) 1879-2596 ; 1879-260X ; 1872-8006 ; 1879-2642 ; 1879-2618 ; 1879-2650
    ISSN 0006-3002 ; 0005-2728 ; 0005-2736 ; 0304-4165 ; 0167-4838 ; 1388-1981 ; 0167-4889 ; 0167-4781 ; 0304-419X ; 1570-9639 ; 0925-4439 ; 1874-9399
    DOI 10.1016/s0304-4165(97)00119-0
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  5. Article: Effects of different molecular weight elastoviscous hyaluronan solutions on articular nociceptive afferents.

    Gomis, Ana / Pawlak, Matthias / Balazs, Endre A / Schmidt, Robert F / Belmonte, Carlos

    Arthritis and rheumatism

    2004  Volume 50, Issue 1, Page(s) 314–326

    Abstract: ... Conclusion: We conclude that the elastoviscous properties of HA solutions are determining factors ... properties substantially different from those of Hyalgan, Orthovisc, and Synvisc, had no such effect ... Objective: To compare 3 different hyaluronan (HA) preparations used as therapeutic agents ...

    Abstract Objective: To compare 3 different hyaluronan (HA) preparations used as therapeutic agents for osteoarthritis pain in humans in order to establish the degree to which a single application affects the sensitivity of nociceptors in both the normal and the acutely inflamed rat joint.
    Methods: In anesthetized rats, single-unit recordings were performed from the medial articular nerve of the right knee joint under normal conditions and during an acute experimental arthritis. Fifty fine afferent units (conduction velocities 0.8-15.3 meters/second) responded to passive movements of the knee joint. They were exposed to a torque meter-controlled, standardized stimulus protocol consisting of innocuous and noxious inward and outward rotations of the joint. This stimulus protocol of 50 seconds' duration was repeated every 5 minutes for 2-3 hours. Three commercially available HA preparations and a buffer solution, the solvent of these preparations, were injected intraarticularly after discharges resulting from 6 stimulus protocols were averaged and used as controls.
    Results: Both in normal and in inflamed joints, the injection of Hyalgan did not reduce nerve impulse frequency of the evoked discharges. The injections of Orthovisc had no effect in normal joints, but produced a transient frequency reduction of the evoked discharge in inflamed joints. Synvisc significantly reduced (by an average of 50%) the impulse discharge in both normal and inflamed joints 50 minutes after injection, and this level of impulse discharge continued until the end of the recording period (120-130 minutes after injection). The buffer, which had elastoviscous properties substantially different from those of Hyalgan, Orthovisc, and Synvisc, had no such effect.
    Conclusion: We conclude that the elastoviscous properties of HA solutions are determining factors in reducing pain-eliciting nerve activity both in normal and in inflamed rat joints.
    MeSH term(s) Animals ; Buffers ; Disease Models, Animal ; Evoked Potentials ; Hyaluronic Acid/analogs & derivatives ; Hyaluronic Acid/chemistry ; Hyaluronic Acid/pharmacology ; Knee Joint/innervation ; Knee Joint/physiopathology ; Male ; Molecular Weight ; Movement ; Neurons, Afferent/physiology ; Nociceptors/physiology ; Osteoarthritis, Knee/complications ; Osteoarthritis, Knee/physiopathology ; Pain/drug therapy ; Pain/etiology ; Pain/physiopathology ; Rats ; Rats, Wistar ; Viscosity
    Chemical Substances Buffers ; hylan (125935-84-4) ; Hyaluronic Acid (9004-61-9)
    Language English
    Publishing date 2004-01
    Publishing country United States
    Document type Comparative Study ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 127294-9
    ISSN 1529-0131 ; 0004-3591 ; 2326-5191
    ISSN (online) 1529-0131
    ISSN 0004-3591 ; 2326-5191
    DOI 10.1002/art.11421
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    Zs.A 24: Show issues Location:
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