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E H Huizing - One of the best experts on this subject based on the ideXlab platform.
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histological structure of the nasal Cartilages and their perichondrial envelope ii the perichondrial envelope of the septal and lobular Cartilage
Rhinology, 2007Co-Authors: Ronald L A W Bleys, Mariola Popko, Janwillem De Groot, E H HuizingAbstract:: The perichondrial envelopes of the septal Cartilage and the lateral crus of the lobular Cartilage were studied in serial coronal sections of five human noses. To differentiate between the various tissue components, the sections were stained according to Mallory-Cason, Azan, Herovici, Verhoeff-van Gieson, and Lawson. Collagen types I and II were immunohistochemically stained. The results demonstrated that the perichondrium of the septal Cartilage and the lateral crus of the lobular Cartilage consists of a homogeneous layer of type I collagen fibers and elastic fibers. The elastic fibers have a network-like arrangement and are most numerous in the perichondrium of the lateral crus of the lobular Cartilage. Clearly distinguishable zones in the perichondrial envelopes could not be observed. The perichondrium on the outside of the lateral crus of the lobular Cartilage and the triangular Cartilage is significantly thicker than the inner perichondrium. It is speculated that these morphological characteristics of the perichondrial envelopes are related to functional differences between the Cartilages. The mobility of the lateral crus of the lobular Cartilage requires a higher content of elastic fibers in its perichondrium than the more rigid septal Cartilage. A thicker outer perichondrium of the lateral crus of the lobular Cartilage and the triangular Cartilage may be related to muscular forces that are exerted on the outer side of the Cartilages only.
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a functional anatomic study of the relationship of the nasal Cartilages and muscles to the nasal valve area
Laryngoscope, 1998Co-Authors: Tjasse D Bruintjes, Adriaan F Van Olphen, Berend Hillen, E H HuizingAbstract:The functioning of the nasal valve area is largely determined by the stability and the mobility of the lateral nasal wall. To gain insight into the kinematics of the lateral nasal wall, we studied the functional anatomy of the nasal muscles and the intercartilaginous and osseous-cartilaginous junctions. We performed gross and microscopic nasal dissection and serial sectioning in 15 human cadaveric noses. In addition, two noses were used for three-dimensional reconstruction of the nasal Cartilages. We conclude that the lateral nasal wall can be seen as made up of three parts. At the level of the osseous-cartilaginous chain of bone, lateral nasal Cartilage, and lateral crus, the lateral nasal wall is relatively stable, limited mobility being allowed by translation and rotation in the intercartilaginous joint and a coupled distortion of the Cartilages. At the level of the hinge area the lateral nasal wall is supported by one or more accessory Cartilages, embedded in soft tissue, and therefore much more compliant. The alar part of the nasalis muscle, which originates from the maxilla and inserts on these Cartilages, may dilate the valve area by drawing this hinge area laterally. The third and most compliant part of the lateral nasal wall is the part that is not supported by Cartilage, the ala. The dilatator naris muscle largely occupies the ala and is attached to the lateral crus; it opens the vestibule and nostril. The third nasal muscle that influences the lateral nasal wall is the transverse part of the nasalis muscle. It overlies the nose but is not attached to it. This muscle stabilizes the lateral nasal wall, in particular, the lateral nasal Cartilage, the intercartilaginous junction, and the hinge area, by moving the nasal skin.
Krishnagoud Manda - One of the best experts on this subject based on the ideXlab platform.
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Time-dependent behavior of Cartilage surrounding a metal implant for full-thickness Cartilage defects of various sizes: a finite element study.
Biomechanics and Modeling in Mechanobiology, 2011Co-Authors: Krishnagoud Manda, Anders ErikssonAbstract:Recently, physiological and biomechanical studies on animal models with metal implants filling full-thickness Cartilage defects have resulted in good clinical outcomes. The knowledge of the time-dependent macroscopic behavior of Cartilage surrounding the metal implant is essential for understanding the joint function after treating such defects. We developed a model to investigate the in vivo time-dependent behavior of the tibiofemoral Cartilages surrounding the metal implant, when the joint is subjected to an axial load for various defect sizes. Results show that time-dependent effects on Cartilage behavior are significant, and can be simulated. These effects should be considered when evaluating the results from an implant. In particular, the depth into the Cartilage where an implant is positioned and the mechanical sealing due to solidification of the poroelastic material need a time aspect. We found the maximal deformations, contact pressures and contact forces in the joint with time for the implant positioned in flush and sunk 0.3 mm into the Cartilage. The latter position gives the better joint performance. The results after 60 s may be treated as the primary results, reflecting the effect of accumulation in the joint due to repeated short-time loadings. The wedge-shaped implant showed beneficial in providing mechanical sealing of Cartilages surrounding the implant with time.
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Simulating Metal Implants in Full Thickness Cartilage Defects
ASME 2011 Summer Bioengineering Conference Parts A and B, 2011Co-Authors: Krishnagoud Manda, Anders ErikssonAbstract:Damage or degeneration in the articular Cartilage is a major problem that affects millions of people in the world. The biomechanical forces at a site of damage in the Cartilage may make the tissue more susceptible to continued long-term degeneration. Various biological treatments are currently available, but all have drawbacks. Alternatively, a contoured articular resurfacing implant is developed to offer a treatment to such full thickness chondral defects [1,3,4]. The main goal of using metal implants, to fill the degenerated portion of the Cartilage, is to seal the surrounding Cartilage so that further damage can be prevented, and to re-establish the integrity of the joint articulating surface. Many researchers have studied the safety, feasibility and reliability of the metal implants in animal models from a biological point of view [3,4]. They showed promising results. Till date, the mechanical behavior of Cartilages surrounding the implant has not been studied, even in animal models. It is essential to understand the time dependent behavior of the Cartilages due to biphasic nature of Cartilage. Any protrusion of metal implant into the joint cavity damages the opposing soft tissue [1]. In order to avoid this, the positioning of implant together with the behavior of the Cartilages immediately surrounding the implant have to be studied.Copyright © 2011 by ASME
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Finite Element Simulations of Biphasic Articular Cartilages With Localized Metal Implants
Journal of biomechanics, 2010Co-Authors: Krishnagoud MandaAbstract:Articular Cartilage is a specialized connective soft tissue that resides on the ends of long-bones, transfers the load smoothly between the bones in di- arthrodial joints by providing almost frictionless, wear resistant sliding surfaces during joint articulation. Focal chondral or osteochondral defects in articular Cartilage are common and show limited capacity for biological repair. Fur- thermore, changes in the bio-mechanical forces at the defect site may make the tissue more susceptible to continued degeneration. Alternatively, the con- toured focal resurfacing metal implant can be used to treat such full thickness Cartilage defects. Physiological and biomechanical studies on animal models with metal implant have shown good clinical outcomes. However, the mechan- ical behavior of Cartilage surrounding the implant is not clearly known with respect to the joint function after treating such defects with metal implants and also to improve the implant design. We developed a simple 3-dimensional finite element model by approximating one of the condyles of the sheep knee joint. Parametric study was conducted in the simulations to verify different profiles for the implant, positioning of the implant with respect to Cartilage surface, defect size and to show the mechanical sealing effect due to the wedge shape of the implant. We found the maximal deformations, contact pressures and stresses which constitute the mechanical behavior of Cartilages. We also confirmed that using a metal implant to fill the full thickness chondral defects is more beneficial than to leave the defect untreated from mechanical point of view. The implant should be positioned slightly sunk into the Cartilage based on the defect size, in order to avoid damage to the opposing surface. The larger the defect size, the closer the implant should be to the flush. We also simulated the time dependent behavior of the Cartilages. In all the simulations, a static axial loading was considered. The wedge shape of the implant provided the mechanical sealing of the Cartilage surrounding the implant. The determined deformations in the Cartilages immediately surrounding the implant are instru- mental in predicting the sticking-up of the implant into the joint cavity which may damage opposing soft tissues.
Kyriacos A Athanasiou - One of the best experts on this subject based on the ideXlab platform.
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toward tissue engineering of nasal Cartilages
Acta Biomaterialia, 2019Co-Authors: Laura Lavernia, Jerry C. Hu, Wendy E Brown, Brian J F Wong, Kyriacos A AthanasiouAbstract:Abstract Nasal Cartilage pathologies are common; for example, up to 80% of people are afflicted by deviated nasal septum conditions. Because Cartilage provides the supportive framework of the nose, afflicted patients suffer low quality of life. To correct pathologies, graft Cartilage is often required. Grafts are currently sourced from the patient’s septum, ear, or rib. However, their use yields donor site morbidity and is limited by tissue quantity and quality. Additionally, rhinoplasty revision rates exceed 15%, exacerbating the shortage of graft Cartilage. Alternative grafts, such as irradiated allogeneic rib Cartilage, are associated with complications. Tissue-engineered neoCartilage holds promise to address the limitations of current grafts. The engineering design process may be used to create suitable graft tissues. This process begins by identifying the surgeon’s needs. Second, nasal Cartilages’ properties must be understood to define engineering design criteria. Limited investigations have examined nasal Cartilage properties; numerous additional studies need to be performed to examine topographical variations, for example. Third, tissue-engineering processes must be applied to achieve the engineering design criteria. Within the recent past, strategies have frequently utilized human septal chondrocytes. As autologous and allogeneic rib graft Cartilage is used, its suitability as a cell source should also be examined. Fourth, quantitative verification of engineered neoCartilage is critical to check for successful achievement of the engineering design criteria. Finally, following the FDA paradigm, engineered neoCartilage must be orthotopically validated in animals. Together, these steps delineate a path to engineer functional nasal neoCartilages that may, ultimately, be used to treat human patients. Statement of Significance Nasal Cartilage pathologies are common and lead to greatly diminished quality of life. The ability to correct pathologies is limited by Cartilage graft quality and quantity, as well as donor site morbidity and surgical complications, such as infection and resorption. Despite the significance of nasal Cartilage pathologies and high rhinoplasty revision rates (15%), little characterization and tissue-engineering work has been performed compared to other Cartilages, such as articular Cartilage. Furthermore, most work is published in clinical journals, with little in biomedical engineering. Therefore, this review discusses what nasal Cartilage properties are known, summarizes the current state of nasal Cartilage tissue-engineering, and makes recommendations via the engineering design process toward engineering functional nasal neoCartilage to address current limitations.
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Characterization of costal Cartilage and its suitability as a cell source for articular Cartilage tissue engineering
Journal of Tissue Engineering and Regenerative Medicine, 2018Co-Authors: Le W. Huwe, Jerry C. Hu, Wendy E Brown, Kyriacos A AthanasiouAbstract:Author(s): Huwe, Le W; Brown, Wendy E; Hu, Jerry C; Athanasiou, Kyriacos A | Abstract: Costal Cartilage is a promising donor source of chondrocytes to alleviate cell scarcity in articular Cartilage tissue engineering. Limited knowledge exists, however, on costal Cartilage characteristics. This study describes the characterization of costal Cartilage and articular Cartilage properties and compares neoCartilage engineered with costal chondrocytes to native articular Cartilage, all within a sheep model. Specifically, we (a) quantitatively characterized the properties of costal Cartilage in comparison to patellofemoral articular Cartilage, and (b) evaluated the quality of neoCartilage derived from costal chondrocytes for potential use in articular Cartilage regeneration. Ovine costal and articular Cartilages from various topographical locations were characterized mechanically, biochemically, and histologically. Costal Cartilage was stiffer in compression but softer and weaker in tension than articular Cartilage. These differences were attributed to high amounts of glycosaminoglycans and mineralization and a low amount of collagen in costal Cartilage. Compared to articular Cartilage, costal Cartilage was more densely populated with chondrocytes, rendering it an excellent chondrocyte source. In terms of tissue engineering, using the self-assembling process, costal chondrocytes formed articular Cartilage-like neoCartilage. Quantitatively compared via a functionality index, neoCartilage achieved 55% of the medial condyle Cartilage mechanical and biochemical properties. This characterization study highlighted the differences between costal and articular Cartilages in native forms and demonstrated that costal Cartilage is a valuable source of chondrocytes suitable for articular Cartilage regeneration strategies.
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Emergence of Scaffold-Free Approaches for Tissue Engineering Musculoskeletal Cartilages
Annals of Biomedical Engineering, 2015Co-Authors: Grayson D. Duraine, Jerry C. Hu, Wendy E Brown, Kyriacos A AthanasiouAbstract:This review explores scaffold-free methods as an additional paradigm for tissue engineering. Musculoskeletal Cartilages—for example articular Cartilage, meniscus, temporomandibular joint disc, and intervertebral disc—are characterized by low vascularity and cellularity, and are amenable to scaffold-free tissue engineering approaches. Scaffold-free approaches, particularly the self-assembling process, mimic elements of developmental processes underlying these tissues. Discussed are various scaffold-free approaches for musculoskeletal Cartilage tissue engineering, such as cell sheet engineering, aggregation, and the self-assembling process, as well as the availability and variety of cells used. Immunological considerations are of particular importance as engineered tissues are frequently of allogeneic, if not xenogeneic, origin. Factors that enhance the matrix production and mechanical properties of these engineered Cartilages are also reviewed, as the fabrication of biomimetically suitable tissues is necessary to replicate function and ensure graft survival in vivo . The concept of combining scaffold-free and scaffold-based tissue engineering methods to address clinical needs is also discussed. Inasmuch as scaffold-based musculoskeletal tissue engineering approaches have been employed as a paradigm to generate engineered Cartilages with appropriate functional properties, scaffold-free approaches are emerging as promising elements of a translational pathway not only for musculoskeletal Cartilages but for other tissues as well.
Jerry C. Hu - One of the best experts on this subject based on the ideXlab platform.
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toward tissue engineering of nasal Cartilages
Acta Biomaterialia, 2019Co-Authors: Laura Lavernia, Jerry C. Hu, Wendy E Brown, Brian J F Wong, Kyriacos A AthanasiouAbstract:Abstract Nasal Cartilage pathologies are common; for example, up to 80% of people are afflicted by deviated nasal septum conditions. Because Cartilage provides the supportive framework of the nose, afflicted patients suffer low quality of life. To correct pathologies, graft Cartilage is often required. Grafts are currently sourced from the patient’s septum, ear, or rib. However, their use yields donor site morbidity and is limited by tissue quantity and quality. Additionally, rhinoplasty revision rates exceed 15%, exacerbating the shortage of graft Cartilage. Alternative grafts, such as irradiated allogeneic rib Cartilage, are associated with complications. Tissue-engineered neoCartilage holds promise to address the limitations of current grafts. The engineering design process may be used to create suitable graft tissues. This process begins by identifying the surgeon’s needs. Second, nasal Cartilages’ properties must be understood to define engineering design criteria. Limited investigations have examined nasal Cartilage properties; numerous additional studies need to be performed to examine topographical variations, for example. Third, tissue-engineering processes must be applied to achieve the engineering design criteria. Within the recent past, strategies have frequently utilized human septal chondrocytes. As autologous and allogeneic rib graft Cartilage is used, its suitability as a cell source should also be examined. Fourth, quantitative verification of engineered neoCartilage is critical to check for successful achievement of the engineering design criteria. Finally, following the FDA paradigm, engineered neoCartilage must be orthotopically validated in animals. Together, these steps delineate a path to engineer functional nasal neoCartilages that may, ultimately, be used to treat human patients. Statement of Significance Nasal Cartilage pathologies are common and lead to greatly diminished quality of life. The ability to correct pathologies is limited by Cartilage graft quality and quantity, as well as donor site morbidity and surgical complications, such as infection and resorption. Despite the significance of nasal Cartilage pathologies and high rhinoplasty revision rates (15%), little characterization and tissue-engineering work has been performed compared to other Cartilages, such as articular Cartilage. Furthermore, most work is published in clinical journals, with little in biomedical engineering. Therefore, this review discusses what nasal Cartilage properties are known, summarizes the current state of nasal Cartilage tissue-engineering, and makes recommendations via the engineering design process toward engineering functional nasal neoCartilage to address current limitations.
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Characterization of costal Cartilage and its suitability as a cell source for articular Cartilage tissue engineering
Journal of Tissue Engineering and Regenerative Medicine, 2018Co-Authors: Le W. Huwe, Jerry C. Hu, Wendy E Brown, Kyriacos A AthanasiouAbstract:Author(s): Huwe, Le W; Brown, Wendy E; Hu, Jerry C; Athanasiou, Kyriacos A | Abstract: Costal Cartilage is a promising donor source of chondrocytes to alleviate cell scarcity in articular Cartilage tissue engineering. Limited knowledge exists, however, on costal Cartilage characteristics. This study describes the characterization of costal Cartilage and articular Cartilage properties and compares neoCartilage engineered with costal chondrocytes to native articular Cartilage, all within a sheep model. Specifically, we (a) quantitatively characterized the properties of costal Cartilage in comparison to patellofemoral articular Cartilage, and (b) evaluated the quality of neoCartilage derived from costal chondrocytes for potential use in articular Cartilage regeneration. Ovine costal and articular Cartilages from various topographical locations were characterized mechanically, biochemically, and histologically. Costal Cartilage was stiffer in compression but softer and weaker in tension than articular Cartilage. These differences were attributed to high amounts of glycosaminoglycans and mineralization and a low amount of collagen in costal Cartilage. Compared to articular Cartilage, costal Cartilage was more densely populated with chondrocytes, rendering it an excellent chondrocyte source. In terms of tissue engineering, using the self-assembling process, costal chondrocytes formed articular Cartilage-like neoCartilage. Quantitatively compared via a functionality index, neoCartilage achieved 55% of the medial condyle Cartilage mechanical and biochemical properties. This characterization study highlighted the differences between costal and articular Cartilages in native forms and demonstrated that costal Cartilage is a valuable source of chondrocytes suitable for articular Cartilage regeneration strategies.
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Articular Cartilage tissue engineering: The role of signaling molecules
Cellular and Molecular Life Sciences, 2016Co-Authors: Heenam Kwon, Nikolaos K. Paschos, Jerry C. Hu, Kyriacos AthanasiouAbstract:Effective early disease modifying options for osteoarthritis remain\nlacking. Tissue engineering approach to generate Cartilage in vitro has\nemerged as a promising option for articular Cartilage repair and\nregeneration. Signaling molecules and matrix modifying agents, derived\nfrom knowledge of Cartilage development and homeostasis, have been used\nas biochemical stimuli toward Cartilage tissue engineering and have led\nto improvements in the functionality of engineered Cartilage. Clinical\ntranslation of neoCartilage faces challenges, such as phenotypic\ninstability of the engineered Cartilage, poor integration, inflammation,\nand catabolic factors in the arthritic environment; these can all\ncontribute to failure of implanted neoCartilage. A comprehensive\nunderstanding of signaling molecules involved in osteoarthritis\npathogenesis and their actions on engineered Cartilage will be crucial.\nThus, while it is important to continue deriving inspiration from\nCartilage development and homeostasis, it has become increasingly\nnecessary to incorporate knowledge from osteoarthritis pathogenesis into\nCartilage tissue engineering.
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Emergence of Scaffold-Free Approaches for Tissue Engineering Musculoskeletal Cartilages
Annals of Biomedical Engineering, 2015Co-Authors: Grayson D. Duraine, Jerry C. Hu, Wendy E Brown, Kyriacos A AthanasiouAbstract:This review explores scaffold-free methods as an additional paradigm for tissue engineering. Musculoskeletal Cartilages—for example articular Cartilage, meniscus, temporomandibular joint disc, and intervertebral disc—are characterized by low vascularity and cellularity, and are amenable to scaffold-free tissue engineering approaches. Scaffold-free approaches, particularly the self-assembling process, mimic elements of developmental processes underlying these tissues. Discussed are various scaffold-free approaches for musculoskeletal Cartilage tissue engineering, such as cell sheet engineering, aggregation, and the self-assembling process, as well as the availability and variety of cells used. Immunological considerations are of particular importance as engineered tissues are frequently of allogeneic, if not xenogeneic, origin. Factors that enhance the matrix production and mechanical properties of these engineered Cartilages are also reviewed, as the fabrication of biomimetically suitable tissues is necessary to replicate function and ensure graft survival in vivo . The concept of combining scaffold-free and scaffold-based tissue engineering methods to address clinical needs is also discussed. Inasmuch as scaffold-based musculoskeletal tissue engineering approaches have been employed as a paradigm to generate engineered Cartilages with appropriate functional properties, scaffold-free approaches are emerging as promising elements of a translational pathway not only for musculoskeletal Cartilages but for other tissues as well.
Robin A Poole - One of the best experts on this subject based on the ideXlab platform.
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comparison of the degradation of type ii collagen and proteoglycan in nasal and articular Cartilages induced by interleukin 1 and the selective inhibition of type ii collagen cleavage by collagenase
Arthritis & Rheumatism, 2000Co-Authors: Clark R Billinghurst, William Wu, Mirela Ionescu, A Reiner, Leif Dahlberg, Jeffrey Chen, Harold E Van Wart, Robin A PooleAbstract:OBJECTIVE: To compare interleukin-1alpha (IL-1alpha)-induced degradation of nasal and articular Cartilages in terms of proteoglycan loss and type II collagen cleavage, denaturation, and release; to examine the temporal relationship of these changes; and to investigate the effects of an inhibitor of collagenase 2 and collagenase 3 on these catabolic processes. METHODS: Discs of mature bovine nasal and articular Cartilages were cultured with or without human IL-1alpha (5 ng/ml) with or without RS102,481, a selective synthetic inhibitor of collagenase 2 and collagenase 3 (matrix metalloproteinase 8 [MMP-8] and MMP-13, respectively) but not of collagenase 1 (MMP-1). Immunoassays were used to measure collagenase-generated type II collagen cleavage neoepitope (antibody COL2-3/4C(short)) and denaturation (antibody COL2-3/4m), as well as total type II collagen content (antibody COL2-3/4m) in articular Cartilage and culture media. A colorimetric assay was used to measure total proteoglycan concentration (principally of aggrecan) as sulfated glycosaminoglycans (sGAG). RESULTS: IL-1alpha initially induced a decrease in tissue proteoglycan content in nasal Cartilage. A progressive loss of proteoglycan was noted during culture in articular Cartilages, irrespective of the presence of IL-1alpha. In both Cartilages, proteoglycan loss was followed by IL-1alpha-induced cleavage of type II collagen by collagenase, which was often reflected by increased denaturation. The inhibitor RS102,481 had no clear effect on the reduction in proteoglycan content (measured by sGAG) and collagen denaturation in either Cartilage, but at 10 nM it inhibited the enhanced cleavage of type II collagen, partially in nasal Cartilage and completely in articular Cartilage. CONCLUSION: IL-1alpha-induced cleavage and denaturation of type II collagen is observed in both hyaline Cartilages and is secondary to proteoglycan loss. It probably involves different collagenases, since there is no evidence of a rate-limiting role for collagenase 1 in articular Cartilage, unlike the case for nasal Cartilage. Inhibitors of this kind may be of value in the treatment of Cartilage damage in arthritis. Also, the ability to detect the release of type II collagen collagenase-generated fragments from degraded Cartilage offers the potential to monitor Cartilage collagen damage and its control in vivo.
