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Ernst B. Hunziker - One of the best experts on this subject based on the ideXlab platform.

  • A new biological glue for Cartilage-Cartilage Interfaces: tissue transglutaminase
    Journal of Hand Surgery (European Volume), 1997
    Co-Authors: Kim Jurgensen, Daniel Aeschlimann, V. Cavin, M. Genge, Ernst B. Hunziker
    Abstract:

    In this study, we used an in vitro model to test the capacity of tissue transglutaminase to increase the adhesive strength at a Cartilage-Cartilage Interface. Full-thickness Cartilage-bone cylinders were prepared from fresh adult bovine shoulder joints, and the superficial half of the hyaline Cartilage was then removed to provide a plane surface. Tissue transglutaminase was applied to the freshly cut surface of one cylinder, and a calcium-chloride solution (to act as an activating agent) was applied to that of the other. The Cartilage surfaces were immediately apposed, one on top of the other, and an eighty-gram weight was applied to the upper cylinder for ten minutes at 37 degrees Celsius under defined humidity conditions. A measured force was then applied transversely to the upper cylinder until it was displaced from the lower one (which was clamped in a holding device), and the force recorded at this point was taken as a measure of the adhesive strength achieved at the Cartilage-Cartilage Interface. The adhesive strength increased linearly with an increasing concentration of tissue transglutaminase (0.25 to 2.75 milligrams per milliliter) and was enhanced by increasing the duration of incubation, but it was not influenced by the level of humidity. The adhesive strength was improved by as much as 40 per cent when the Cartilage surfaces had been pretreated with chondroitinase AC or hyaluronidase to remove glycosaminoglycan chains of proteoglycans, which are largely responsible for the intrinsic anti-adhesive properties of Cartilage.

  • A new biological glue for Cartilage-Cartilage Interfaces: tissue transglutaminase.
    Journal of Bone and Joint Surgery American Volume, 1997
    Co-Authors: Kim Jurgensen, Daniel Aeschlimann, V. Cavin, M. Genge, Ernst B. Hunziker
    Abstract:

    In this study, we used an in vitro model to test the capacity of tissue transglutaminase to increase the adhesive strength at a Cartilage-Cartilage Interface. Full-thickness Cartilage-bone cylinders were prepared from fresh adult bovine shoulder joints, and the superficial half of the hyaline Cartilage was then removed to provide a plane surface. Tissue transglutaminase was applied to the freshly cut surface of one cylinder, and a calcium-chloride solution (to act as an activating agent) was applied to that of the other. The Cartilage surfaces were immediately apposed, one on top of the other, and an eighty-gram weight was applied to the upper cylinder for ten minutes at 37 degrees Celsius under defined humidity conditions. A measured force was then applied transversely to the upper cylinder until it was displaced from the lower one (which was clamped in a holding device), and the force recorded at this point was taken as a measure of the adhesive strength achieved at the Cartilage-Cartilage Interface. The adhesive strength increased linearly with an increasing concentration of tissue transglutaminase (0.25 to 2.75 milligrams per milliliter) and was enhanced by increasing the duration of incubation, but it was not influenced by the level of humidity. The adhesive strength was improved by as much as 40 per cent when the Cartilage surfaces had been pretreated with chondroitinase AC or hyaluronidase to remove glycosaminoglycan chains of proteoglycans, which are largely responsible for the intrinsic anti-adhesive properties of Cartilage. CLINICAL RELEVANCE: The mechanical fixation of Cartilage fragments in diarthrodial joints and the fixation and immobilization of Cartilage transplant materials or biodegradable matrices containing chondrogenic cells pose serious problems for the orthopaedic surgeon. In the present study, the adhesive strength achieved with use of tissue transglutaminase at the Cartilage-Cartilage Interface was greater than that obtained with use of Tissucol, a commercially available fibrin sealant. Tissue transglutaminase thus has great promise for practical application in clinical orthopaedics. Because this material has a relatively simple single-polypeptide-chain structure, production of the substance in large quantities with use of recombinant DNA technology is feasible. As a biological adhesive, it thus offers new possibilities for improving the repertoire for the treatment of chondral lesions.

D.a. Bradley - One of the best experts on this subject based on the ideXlab platform.

  • Elemental and structural studies at the bone-Cartilage Interface
    2012
    Co-Authors: D.a. Bradley, W. Kaabar, Ozcan Gundogdu
    Abstract:

    The techniques μProton-Induced X-and γ-ray Emission, μ-PIXE and μ-PIGE, were used to investigate trace and essential element distributions in sections of normal and osteoarthritic (OA) human femoral head. μ-PIGE yielded 2-D mappings of Na and F while Ca, Z, P and S were mapped by μ-PIXE. The concentration of chondroitin sulphate supporting functionality in healthy Cartilage is significantly reduced in OA samples. Localised Zn points to osteoblastic/osteoclastic activity at the bone-Cartilage Interface. Small-angle X-ray scattering applied to decalcified OA-affected tissue showed spatial alterations of collagen fibres of decreased axial periodicity compared to normal collagen type I.

  • Elemental and structural studies at the bone-Cartilage Interface
    Nuclear Instruments and Methods in Physics Research Section A: Accelerators Spectrometers Detectors and Associated Equipment, 2011
    Co-Authors: W. Kaabar, Eman Daar, Ozcan Gundogdu, Chris Jeynes, A. Laklouk, Oliver Bunk, Michael J. Farquharson, Melanie J. Bailey, D.a. Bradley
    Abstract:

    Micro-Proton Induced X-ray Emission (μ-PIXE) and Proton Induced Gamma-ray Emission (PIGE) techniques were employed in the investigation of trace and essential elements distribution in normal and diseased human femoral head sections affected by osteoarthritis (OA). PIGE was exploited in the determination of elements of low atomic number z 15 viz Ca, Z, P and S were determined by PIXE. Accumulations of key elements in the bone and Cartilage sections were observed, significant S and Na concentrations being found in the Cartilage region particularly in normal tissues. Zn showed enhanced concentrations at the bone–Cartilage Interface. At a synchrotron facility, small angle X-ray scattering (SAXS) was utilized on a decalcified human femoral head section affected by OA, direct measurements being made of spatial alterations of collagen fibres. The SAXS results showed a slight decrease in the axial periodicity between normal collagen type I and that in diseased tissue in various sites, in contrast with the findings of others.

  • compositional and structural studies of the bone Cartilage Interface using pixe and saxs techniques
    Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2010
    Co-Authors: W. Kaabar, M. J. Farquharson, A. Laklouk, Oliver Bunk, M. Baily, D.a. Bradley
    Abstract:

    Abstract Micro-proton-induced X-ray emission (μ-PIXE) analysis has been employed in investigating the presence of number of essential anions and cations in thin sections of diseased human articular Cartilage affected by osteoarthritis (OA). Distribution maps for Ca, P, K and S in diseased sections show marked alterations in the concentrations of these at the bone–Cartilage Interface compared to normal tissue. For a decalcified section of human articular Cartilage, organisational changes of the collagen network were investigated by small-angle X-ray scattering (SAXS). The established gradual reorientation of collagen fibres from vertical to the surface of the joint to normal to the bone–Cartilage Interface is observed to be heavily disrupted in OA.

  • μ pixe and saxs studies at the bone Cartilage Interface
    Applied Radiation and Isotopes, 2010
    Co-Authors: W. Kaabar, M. J. Farquharson, A. Laklouk, Oliver Bunk, O. Gundogdu, Franz Pfeiffer, D.a. Bradley
    Abstract:

    Micro Proton Induced X-ray Emission (mu-PIXE) analysis has been employed herein in investigating and quantifying the distribution of a number of essential elements in thin human diseased articular Cartilage sections affected by osteoarthritis (OA). Various cations Ca, P and Zn have been reported to play an important role both in the normal growth and remodelling of articular Cartilage and subchondral bone as well as in the degenerative and inflammatory processes associated with the disease; they act as co-factors of a class of enzymes known as metalloproteinases which are believed to be active during the initiation, progress and remodelling processes associated with osteoarthritis. Other important enzymes such as alkaline phosphatase are associated with Cartilage mineralization. Synchrotron radiation X-ray fluorescence (SR-XRF) for mapping of elemental distributions in bone and Cartilage has also been employed by the present group and others. In the current investigations using the cSAXS beamline at the Swiss light source, Small-Angle X-ray Scattering (SAXS) was carried out on decalcified human articular Cartilage to explore the structural and organizational changes of collagen networks in diseased articular Cartilage. (c) 2009 Elsevier Ltd. All rights reserved.

  • Compositional and structural studies of the bone–Cartilage Interface using PIXE and SAXS techniques
    Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2010
    Co-Authors: W. Kaabar, M. J. Farquharson, A. Laklouk, Oliver Bunk, M. Baily, D.a. Bradley
    Abstract:

    Abstract Micro-proton-induced X-ray emission (μ-PIXE) analysis has been employed in investigating the presence of number of essential anions and cations in thin sections of diseased human articular Cartilage affected by osteoarthritis (OA). Distribution maps for Ca, P, K and S in diseased sections show marked alterations in the concentrations of these at the bone–Cartilage Interface compared to normal tissue. For a decalcified section of human articular Cartilage, organisational changes of the collagen network were investigated by small-angle X-ray scattering (SAXS). The established gradual reorientation of collagen fibres from vertical to the surface of the joint to normal to the bone–Cartilage Interface is observed to be heavily disrupted in OA.

Kim Jurgensen - One of the best experts on this subject based on the ideXlab platform.

  • A new biological glue for Cartilage-Cartilage Interfaces: tissue transglutaminase
    Journal of Hand Surgery (European Volume), 1997
    Co-Authors: Kim Jurgensen, Daniel Aeschlimann, V. Cavin, M. Genge, Ernst B. Hunziker
    Abstract:

    In this study, we used an in vitro model to test the capacity of tissue transglutaminase to increase the adhesive strength at a Cartilage-Cartilage Interface. Full-thickness Cartilage-bone cylinders were prepared from fresh adult bovine shoulder joints, and the superficial half of the hyaline Cartilage was then removed to provide a plane surface. Tissue transglutaminase was applied to the freshly cut surface of one cylinder, and a calcium-chloride solution (to act as an activating agent) was applied to that of the other. The Cartilage surfaces were immediately apposed, one on top of the other, and an eighty-gram weight was applied to the upper cylinder for ten minutes at 37 degrees Celsius under defined humidity conditions. A measured force was then applied transversely to the upper cylinder until it was displaced from the lower one (which was clamped in a holding device), and the force recorded at this point was taken as a measure of the adhesive strength achieved at the Cartilage-Cartilage Interface. The adhesive strength increased linearly with an increasing concentration of tissue transglutaminase (0.25 to 2.75 milligrams per milliliter) and was enhanced by increasing the duration of incubation, but it was not influenced by the level of humidity. The adhesive strength was improved by as much as 40 per cent when the Cartilage surfaces had been pretreated with chondroitinase AC or hyaluronidase to remove glycosaminoglycan chains of proteoglycans, which are largely responsible for the intrinsic anti-adhesive properties of Cartilage.

  • A new biological glue for Cartilage-Cartilage Interfaces: tissue transglutaminase.
    Journal of Bone and Joint Surgery American Volume, 1997
    Co-Authors: Kim Jurgensen, Daniel Aeschlimann, V. Cavin, M. Genge, Ernst B. Hunziker
    Abstract:

    In this study, we used an in vitro model to test the capacity of tissue transglutaminase to increase the adhesive strength at a Cartilage-Cartilage Interface. Full-thickness Cartilage-bone cylinders were prepared from fresh adult bovine shoulder joints, and the superficial half of the hyaline Cartilage was then removed to provide a plane surface. Tissue transglutaminase was applied to the freshly cut surface of one cylinder, and a calcium-chloride solution (to act as an activating agent) was applied to that of the other. The Cartilage surfaces were immediately apposed, one on top of the other, and an eighty-gram weight was applied to the upper cylinder for ten minutes at 37 degrees Celsius under defined humidity conditions. A measured force was then applied transversely to the upper cylinder until it was displaced from the lower one (which was clamped in a holding device), and the force recorded at this point was taken as a measure of the adhesive strength achieved at the Cartilage-Cartilage Interface. The adhesive strength increased linearly with an increasing concentration of tissue transglutaminase (0.25 to 2.75 milligrams per milliliter) and was enhanced by increasing the duration of incubation, but it was not influenced by the level of humidity. The adhesive strength was improved by as much as 40 per cent when the Cartilage surfaces had been pretreated with chondroitinase AC or hyaluronidase to remove glycosaminoglycan chains of proteoglycans, which are largely responsible for the intrinsic anti-adhesive properties of Cartilage. CLINICAL RELEVANCE: The mechanical fixation of Cartilage fragments in diarthrodial joints and the fixation and immobilization of Cartilage transplant materials or biodegradable matrices containing chondrogenic cells pose serious problems for the orthopaedic surgeon. In the present study, the adhesive strength achieved with use of tissue transglutaminase at the Cartilage-Cartilage Interface was greater than that obtained with use of Tissucol, a commercially available fibrin sealant. Tissue transglutaminase thus has great promise for practical application in clinical orthopaedics. Because this material has a relatively simple single-polypeptide-chain structure, production of the substance in large quantities with use of recombinant DNA technology is feasible. As a biological adhesive, it thus offers new possibilities for improving the repertoire for the treatment of chondral lesions.

Patricia A. Kolowich - One of the best experts on this subject based on the ideXlab platform.

  • Full-Thickness and Partial-Thickness Supraspinatus Tendon Tears: Value of US Signs in Diagnosis
    Radiology, 2004
    Co-Authors: Jon A. Jacobson, Scott Lancaster, Amitesh Prasad, Marnix Van Holsbeeck, Josesph G Craig, Patricia A. Kolowich
    Abstract:

    Purpose To determine which US signs are important in the diagnosis of a surgically identifiable supraspinatus tendon tear. Materials and methods Fifty consecutive ultrasonographic (US) studies of the shoulder in patients who underwent arthroscopic follow-up were retrospectively reviewed by a musculoskeletal radiologist. US images of the supraspinatus tendon were evaluated for tendon nonvisualization, abnormal tendon echogenicity, tendon thinning, greater tuberosity cortical irregularity, Cartilage Interface sign, joint fluid, and subacromial-subdeltoid bursal fluid. US findings were compared with arthroscopic results. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated for each US sign in the diagnosis of full-thickness tendon tear and again for any type of supraspinatus tendon tear. Results Arthroscopy revealed 21 full-thickness tears, five bursal surface partial-thickness tears, 10 articular surface partial-thickness tears, and 14 patients without tear of the supraspinatus tendon. The presence of greater tuberosity cortical irregularity and joint fluid was most important in the diagnosis of full-thickness supraspinatus tendon tear (sensitivity, 60%; specificity, 100%; positive predictive value, 100%; negative predictive value, 78%; accuracy, 84%). For diagnosis of any type of supraspinatus tendon tear (partial or full thickness), tendon nonvisualization, greater tuberosity cortical irregularity, and Cartilage Interface sign are most important, although a combination of signs did not improve accuracy. Conclusion Secondary US signs, such as greater tuberosity cortical irregularity and joint fluid, are most valuable in the diagnosis of supraspinatus tendon tear.

Daniel Aeschlimann - One of the best experts on this subject based on the ideXlab platform.

  • A new biological glue for Cartilage-Cartilage Interfaces: tissue transglutaminase
    Journal of Hand Surgery (European Volume), 1997
    Co-Authors: Kim Jurgensen, Daniel Aeschlimann, V. Cavin, M. Genge, Ernst B. Hunziker
    Abstract:

    In this study, we used an in vitro model to test the capacity of tissue transglutaminase to increase the adhesive strength at a Cartilage-Cartilage Interface. Full-thickness Cartilage-bone cylinders were prepared from fresh adult bovine shoulder joints, and the superficial half of the hyaline Cartilage was then removed to provide a plane surface. Tissue transglutaminase was applied to the freshly cut surface of one cylinder, and a calcium-chloride solution (to act as an activating agent) was applied to that of the other. The Cartilage surfaces were immediately apposed, one on top of the other, and an eighty-gram weight was applied to the upper cylinder for ten minutes at 37 degrees Celsius under defined humidity conditions. A measured force was then applied transversely to the upper cylinder until it was displaced from the lower one (which was clamped in a holding device), and the force recorded at this point was taken as a measure of the adhesive strength achieved at the Cartilage-Cartilage Interface. The adhesive strength increased linearly with an increasing concentration of tissue transglutaminase (0.25 to 2.75 milligrams per milliliter) and was enhanced by increasing the duration of incubation, but it was not influenced by the level of humidity. The adhesive strength was improved by as much as 40 per cent when the Cartilage surfaces had been pretreated with chondroitinase AC or hyaluronidase to remove glycosaminoglycan chains of proteoglycans, which are largely responsible for the intrinsic anti-adhesive properties of Cartilage.

  • A new biological glue for Cartilage-Cartilage Interfaces: tissue transglutaminase.
    Journal of Bone and Joint Surgery American Volume, 1997
    Co-Authors: Kim Jurgensen, Daniel Aeschlimann, V. Cavin, M. Genge, Ernst B. Hunziker
    Abstract:

    In this study, we used an in vitro model to test the capacity of tissue transglutaminase to increase the adhesive strength at a Cartilage-Cartilage Interface. Full-thickness Cartilage-bone cylinders were prepared from fresh adult bovine shoulder joints, and the superficial half of the hyaline Cartilage was then removed to provide a plane surface. Tissue transglutaminase was applied to the freshly cut surface of one cylinder, and a calcium-chloride solution (to act as an activating agent) was applied to that of the other. The Cartilage surfaces were immediately apposed, one on top of the other, and an eighty-gram weight was applied to the upper cylinder for ten minutes at 37 degrees Celsius under defined humidity conditions. A measured force was then applied transversely to the upper cylinder until it was displaced from the lower one (which was clamped in a holding device), and the force recorded at this point was taken as a measure of the adhesive strength achieved at the Cartilage-Cartilage Interface. The adhesive strength increased linearly with an increasing concentration of tissue transglutaminase (0.25 to 2.75 milligrams per milliliter) and was enhanced by increasing the duration of incubation, but it was not influenced by the level of humidity. The adhesive strength was improved by as much as 40 per cent when the Cartilage surfaces had been pretreated with chondroitinase AC or hyaluronidase to remove glycosaminoglycan chains of proteoglycans, which are largely responsible for the intrinsic anti-adhesive properties of Cartilage. CLINICAL RELEVANCE: The mechanical fixation of Cartilage fragments in diarthrodial joints and the fixation and immobilization of Cartilage transplant materials or biodegradable matrices containing chondrogenic cells pose serious problems for the orthopaedic surgeon. In the present study, the adhesive strength achieved with use of tissue transglutaminase at the Cartilage-Cartilage Interface was greater than that obtained with use of Tissucol, a commercially available fibrin sealant. Tissue transglutaminase thus has great promise for practical application in clinical orthopaedics. Because this material has a relatively simple single-polypeptide-chain structure, production of the substance in large quantities with use of recombinant DNA technology is feasible. As a biological adhesive, it thus offers new possibilities for improving the repertoire for the treatment of chondral lesions.