Journal articles: 'Elastic tissue'

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Saitow, Cassandra B., Steven G. Wise, Anthony S. Weiss, John J. Castellot, and David L. Kaplan. "Elastin biology and tissue engineering with adult cells." BioMolecular Concepts 4, no. 2 (April 1, 2013): 173–85. http://dx.doi.org/10.1515/bmc-2012-0040.

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AbstractThe inability of adult cells to produce well-organized, robust elastic fibers has long been a barrier to the successful engineering of certain tissues. In this review, we focus primarily on elastin with respect to tissue-engineered vascular substitutes. To understand elastin regulation during normal development, we describe the role of various elastic fiber accessory proteins. Biochemical pathways regulating expression of the elastin gene are addressed, with particular focus on tissue-engineering research using adult-derived cells.

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White, J. F., J. L. Hughes, J. S. Kumaratilake, J. C. Fanning, M. A. Gibson, R. Krishnan, and E. G. Cleary. "Post-embedding methods for immunolocalization of elastin and related components in tissues." Journal of Histochemistry & Cytochemistry 36, no. 12 (December 1988): 1543–51. http://dx.doi.org/10.1177/36.12.3142951.

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Elastic tissue is composed of amorphous-appearing elastin and 12-nm diameter microfibrils, one component of which has recently been isolated and characterized as the 31 KD microfibril-associated glycoprotein MAGP. Monospecific antibodies to each of these components have been developed in this laboratory. The parameters that determine optimal localization of colloidal gold probes for post-embedding immunolabeling of elastic tissue components have been systematically studied in a variety of normal and developing tissues in mammals and birds. Protein A-gold probes stabilized with dextran have been shown to provide complexes that remain stable after more than 2 years. Conditions have been defined that permit precise localization within the extracellular matrix of antibodies to MAGP and to elastin, singly and together. Best results were obtained with acrylic resins (Lowicryl K4M or LR White). Fixation in glutaraldehyde or other aldehydic fixatives, with or without osmium, did not affect the immunostaining of elastic tissue with affinity-purified antibodies to tropoelastin, or to anti-[alpha-elastin] or anti-[alkali-insoluble elastin]. Immunostaining with the anti-MAGP antibody was less robust and was possible in tissues which had been fixed only lightly before embedding in Lowicryl K4M or LR White. This staining was enhanced by metaperiodate oxidation of the sections as well as by reduction of the tissues with sodium borohydride en bloc, followed by hyaluronidase digestion of the sections. The effects on immunostaining of a range of enzyme digestions have also been examined. Conditions have thus been defined that make possible detailed study of the relationship between elastic tissue, elastin-associated microfibrils, and other microfibrillar structures in normal and abnormal tissues during development and aging.

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Green, Ellen M., Jessica C. Mansfield, James S. Bell, and C. Peter Winlove. "The structure and micromechanics of elastic tissue." Interface Focus 4, no. 2 (April 6, 2014): 20130058. http://dx.doi.org/10.1098/rsfs.2013.0058.

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Elastin is a major component of tissues such as lung and blood vessels, and endows them with the long-range elasticity necessary for their physiological functions. Recent research has revealed the complexity of these elastin structures and drawn attention to the existence of extensive networks of fine elastin fibres in tissues such as articular cartilage and the intervertebral disc. Nonlinear microscopy, allowing the visualization of these structures in living tissues, is informing analysis of their mechanical properties. Elastic fibres are complex in composition and structure containing, in addition to elastin, an array of microfibrillar proteins, principally fibrillin. Raman microspectrometry and X-ray scattering have provided new insights into the mechanisms of elasticity of the individual component proteins at the molecular and fibrillar levels, but more remains to be done in understanding their mechanical interactions in composite matrices. Elastic tissue is one of the most stable components of the extracellular matrix, but impaired mechanical function is associated with ageing and diseases such as atherosclerosis and diabetes. Efforts to understand these associations through studying the effects of processes such as calcium and lipid binding and glycation on the mechanical properties of elastin preparations in vitro have produced a confusing picture, and further efforts are required to determine the molecular basis of such effects.

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Trębacz, Hanna, and Angelika Barzycka. "Mechanical Properties and Functions of Elastin: An Overview." Biomolecules 13, no. 3 (March 22, 2023): 574. http://dx.doi.org/10.3390/biom13030574.

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Human tissues must be elastic, much like other materials that work under continuous loads without losing functionality. The elasticity of tissues is provided by elastin, a unique protein of the extracellular matrix (ECM) of mammals. Its function is to endow soft tissues with low stiffness, high and fully reversible extensibility, and efficient elastic–energy storage. Depending on the mechanical functions, the amount and distribution of elastin-rich elastic fibers vary between and within tissues and organs. The article presents a concise overview of the mechanical properties of elastin and its role in the elasticity of soft tissues. Both the occurrence of elastin and the relationship between its spatial arrangement and mechanical functions in a given tissue or organ are overviewed. As elastin in tissues occurs only in the form of elastic fibers, the current state of knowledge about their mechanical characteristics, as well as certain aspects of degradation of these fibers and their mechanical performance, is presented. The overview also outlines the latest understanding of the molecular basis of unique physical characteristics of elastin and, in particular, the origin of the driving force of elastic recoil after stretching.

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Subramaniam, K., H. Kumar, and M. H. Tawhai. "Evidence for age-dependent air-space enlargement contributing to loss of lung tissue elastic recoil pressure and increased shear modulus in older age." Journal of Applied Physiology 123, no. 1 (July 1, 2017): 79–87. http://dx.doi.org/10.1152/japplphysiol.00208.2016.

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As a normal part of mature aging, lung tissue undergoes microstructural changes such as alveolar air-space enlargement and redistribution of collagen and elastin away from the alveolar duct. The older lung also experiences an associated decrease in elastic recoil pressure and an increase in specific tissue elastic moduli, but how this relates mechanistically to microstructural remodeling is not well-understood. In this study, we use a structure-based mechanics analysis to elucidate the contributions of age-related air-space enlargement and redistribution of elastin and collagen to loss of lung elastic recoil pressure and increase in tissue elastic moduli. Our results show that age-related geometric changes can result in reduction of elastic recoil pressure and increase in shear and bulk moduli, which is consistent with published experimental data. All elastic moduli were sensitive to the distribution of stiffness (representing elastic fiber density) in the alveolar wall, with homogenous stiffness near the duct and through the septae resulting in a more compliant tissue. The preferential distribution of elastic proteins around the alveolar duct in the healthy young adult lung therefore provides for a more elastic tissue. NEW & NOTEWORTHY We use a structure-based mechanics analysis to correlate air-space enlargement and redistribution of elastin and collagen to age-related changes in the mechanical behavior of lung parenchyma. Our study highlights that both the cause (redistribution of elastin and collagen) and the structural effect (alveolar air-space enlargement) contribute to decline in lung tissue elastic recoil with age; these results are consistent with published data and provide a new avenue for understanding the mechanics of the older lung.

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Lewis, Kevan G., Lionel Bercovitch, Sara W. Dill, and Leslie Robinson-Bostom. "Acquired disorders of elastic tissue: Part II. decreased elastic tissue." Journal of the American Academy of Dermatology 51, no. 2 (August 2004): 165–85. http://dx.doi.org/10.1016/j.jaad.2004.03.016.

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Atarashi, Masaki, Keiichi Miyamoto, and Takashi Horiuchi. "Development of Elastin Biomaterial for Elastic Tissue Engineering." Journal of Life Support Engineering 17, Supplement (2005): 77. http://dx.doi.org/10.5136/lifesupport.17.supplement_77.

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Roark, E. F., D. R. Keene, C. C. Haudenschild, S. Godyna, C. D. Little, and W. S. Argraves. "The association of human fibulin-1 with elastic fibers: an immunohistological, ultrastructural, and RNA study." Journal of Histochemistry & Cytochemistry 43, no. 4 (April 1995): 401–11. http://dx.doi.org/10.1177/43.4.7534784.

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We examined the pattern of fibulin-1 mRNA and protein expression in human tissues and cell lines. Fibulin-1 transcripts were found in RNA isolated from most tissues and a variety of cultured cells, including fibroblasts, smooth muscle cells, and several epithelial cell lines, but not endothelial cells, lymphomyloid cells, or a number of carcinoma and melanoma lines. Immunohistochemical analysis showed that fibulin-1 is an intercellular component of connective tissues, predominantly associated with matrix fibers in tissues such as the cervix, dermis, intimal and medial layers of blood vessels, heart valves, meningeal tissue of the brain, Wharton's jelly of the umbilical cord, testis, and lung. Most of the fibers that were immunoreactive with fibulin-1 antibodies also stained with antibodies to the elastic fiber proteins elastin and fibrillin, as well as with Verhoeff's elastin stain. Immunoelectron microscopic analysis of elastin fibers of skin and saphenous vein revealed that fibulin-1 was located within the amorphous core of the fibers, similar to elastin, but it was not in the fibrillin-containing, elastin-associated microfibrils. Our finding that fibulin-1 is an elastic fiber component suggests several possible new functions for fibulin-1, e.g., that it is a structural protein that contributes to the elastic properties of connective tissue fibers or that is involved with the process of fibrogenesis.

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Fanning, J. C., and E. G. Cleary. "Identification of glycoproteins associated with elastin-associated microfibrils." Journal of Histochemistry & Cytochemistry 33, no. 4 (April 1985): 287–94. http://dx.doi.org/10.1177/33.4.3980982.

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The microfibrils associated with elastic tissue have been shown to be predominantly proteinaceous. On the basis of their affinity for cationic stains, including ruthenium red, they have been assumed to be glycoprotein, but more evidence to support this claim has not been adduced. Despite repeated investigation of glycoprotein materials obtained by extraction of elastic tissues with reagents that appear to remove microfibrils, the chemical composition of elastin-associated microfibrils remains obscure. An electron microscopic study of the microfibrils in two elastin-rich tissues (bovine nuchal ligament and aorta) during their development was pursued using more specific histochemical methods. The periodic acid-alkaline bismuth stain (analogous to the periodic acid-Schiff stain for glycoproteins in light microscopy) has been adapted for this study. Specific aldehyde groups (confirmed by blocking with m-aminophenol or sodium borohydride) were identified after periodate oxidation as fine granules of bismuth stain. These were shown to localize specifically along the elastin-associated microfibrils in a finely punctate form. Staining of the amorphous elastic component did not occur except for a fine rim adjacent to the microfibrils. Lectin binding with concanavalin A (with ferritin markers) confirmed that there are glucose- or mannose-containing proteins associated with the microfibrillar component of elastic tissue. This was true of these microfibrils in all layers of the aortic wall and throughout the ligament. It was also true of mature adult tissues in which there was a lesser proportion of microfibrils. It is concluded that elastin-associated microfibrils really are associated with glycoprotein(s).

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10

Andrés-Ramos, Irene, Victoria Alegría-Landa, Ignacio Gimeno, Alejandra Pérez-Plaza, Arno Rütten, Heinz Kutzner, and Luis Requena. "Cutaneous Elastic Tissue Anomalies." American Journal of Dermatopathology 41, no. 2 (February 2019): 85–117. http://dx.doi.org/10.1097/dad.0000000000001275.

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Fanning, J. C., J. F. White, J. Kumaratilake, M. A. Gibson, and E. G. Cleary. "Immunoelectron microscopy in normal and diseased elastic tissues." Proceedings, annual meeting, Electron Microscopy Society of America 45 (August 1987): 620–21. http://dx.doi.org/10.1017/s0424820100127530.

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Elastic tissue is recognised to be composed of a major amorphous component (consisting of the protein elastin) and a lesser microfibrillar component (complex structures containing at least two glycoproteins). The study of the components of elastic fibers in developing tissues has been hampered by the difficulty of establishing that the amorphous component is distinguishable from other amorphous structures. This is particularly a problem when the elastic material is deranged, so that the amorphous component is atypical in appearance. We have developed, in rabbits, and then affinity-purified, polyclonal antibodies to each of elastin (the amorphous component), “reductive guanidine extracts” of fetal bovine nuchal ligament and to a microfibril-associated glycoprotein (MAGP) isolated from these extracts.Samples of fetal and adult bovine tissues, including aorta, skin and nuchal ligament; and human tissues; including skin, aorta and breast cancers, were fixed for 4 h in 4% paraformaldehyde and 0.2% glutaraldehyde in phosphate buffered saline, pH 7.4, containing 4% sucrose and 5% polyvinyl pyrolidine;

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12

Mecham, Robert P. "Methods in elastic tissue biology: Elastin isolation and purification." Methods 45, no. 1 (May 2008): 32–41. http://dx.doi.org/10.1016/j.ymeth.2008.01.007.

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13

Lammers, Steven R., Phil H. Kao, H. Jerry Qi, Kendall Hunter, Craig Lanning, Joseph Albietz, Stephen Hofmeister, Robert Mecham, Kurt R. Stenmark, and Robin Shandas. "Changes in the structure-function relationship of elastin and its impact on the proximal pulmonary arterial mechanics of hypertensive calves." American Journal of Physiology-Heart and Circulatory Physiology 295, no. 4 (October 2008): H1451—H1459. http://dx.doi.org/10.1152/ajpheart.00127.2008.

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Extracellular matrix remodeling has been proposed as one mechanism by which proximal pulmonary arteries stiffen during pulmonary arterial hypertension (PAH). Although some attention has been paid to the role of collagen and metallomatrix proteins in affecting vascular stiffness, much less work has been performed on changes in elastin structure-function relationships in PAH. Such work is warranted, given the importance of elastin as the structural protein primarily responsible for the passive elastic behavior of these conduit arteries. Here, we study structure-function relationships of fresh arterial tissue and purified arterial elastin from the main, left, and right pulmonary artery branches of normotensive and hypoxia-induced pulmonary hypertensive neonatal calves. PAH resulted in an average 81 and 72% increase in stiffness of fresh and digested tissue, respectively. Increase in stiffness appears most attributable to elevated elastic modulus, which increased 46 and 65%, respectively, for fresh and digested tissue. Comparison between fresh and digested tissues shows that, at 35% strain, a minimum of 48% of the arterial load is carried by elastin, and a minimum of 43% of the change in stiffness of arterial tissue is due to the change in elastin stiffness. Analysis of the stress-strain behavior revealed that PAH causes an increase in the strains associated with the physiological pressure range but had no effect on the strain of transition from elastin-dominant to collagen-dominant behavior. These results indicate that mechanobiological adaptations of the continuum and geometric properties of elastin, in response to PAH, significantly elevate the circumferential stiffness of proximal pulmonary arterial tissue.

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Ateş Özdemir, Deniz, and Kader Susesi. "The Potential Use of Elastic Tissue Autofluorescence in Formalin-fixed Paraffin-embedded Skin Biopsies." Acta Medica 53, no. 1 (March 17, 2022): 37–43. http://dx.doi.org/10.32552/2022.actamedica.655.

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Autofluorescence (AF) or naïve-florescence is the natural emission of light by biomolecules. During florescence microscope examination, we realized that elastic tissue is brighter or more autoflourescent than collagen and other biomolecules/cells in the skin. Consequently, we decided to review elastic tissue-related pathologies under a florescence microscope and to report the possible benefits of this technique from selected cases from the paraffin-block archive, by using the protease digestion immunofluorescence method. Selected and clinic-pathologically confirmed 3 elastofibroma dorsi, 3 pseudoxanthoma elasticum, 3 anetoderma, 3 arteriovenous malformations, 3 temporal arteritis, 3 scar tissue and 3 highly solar-damaged samples of skin from 2014-2019 were retrieved. Under the fluorescent microscope, coarse, thick and globularly-fragmented elastic fibers of elastofibroma dorsi, shortened, irregular and convoluted elastic fibers of pseudoxanthoma elasticum, internal elastic membranes of arteries and their integrity was visualized. None of the anetoderma cases had any signal representing elastic tissue. It was shown that elastic tissue can be observed easily under fluorescence microscope in the case of FFPE tissues. The resulting autofluorescence can be useful in recognizing elastic tissue-related pathologies, and it may be used as an ancillary or an alternative method to routine histochemical techniques.

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Perelmuter, Mikhail. "Stress concentration in bone tissues and screw dental implants." Russian journal of biomechanics. 27, no. 2 (June 30, 2023): 12–20. http://dx.doi.org/10.15593/rjbiomech/2023.2.02.

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Analysis of stress concentration in bone tissues and screw dental implants was per-formed on a model of screw join of the implant and surrounding bone tissues under the action of normal and tangential loads. The computations were performed by the bounda-ry element method for the plane strain state. It was assumed that those hollows in the spongy bone, which had formed in the bone after the implant insertion, are conformed to the screw thread on the implant. Bone tissues are considered as an isotropic and homo-geneous linear-elastic materials. It has been found that with the increasing in the spongy bone tissue elastic modulus, the maximum equivalent stresses in this bone tissue in-crease. Stresses in the cortical bone tissue decrease with the increasing in the spongy bone elastic modulus due to the decreasing in the load transferred to this bone part. Stresses in the spongy bone decrease with the increasing of the cortical bone layer elas-ticity modulus. The level of maximum stress in the cortical layer of the bone increases with the increasing of this bone tissue elastic modulus. The maximum of stresses in the cortical bone tissue are observed near the implant neck.

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Roten, Sonja Vollenweider, Shailesh Bhat, and Jag Bhawan. "Elastic fibers in scar tissue." Journal of Cutaneous Pathology 23, no. 1 (February 1996): 37–42. http://dx.doi.org/10.1111/j.1600-0560.1996.tb00775.x.

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Adams, Brian B., and Diya F. Mutasim. "Elastic Tissue in Fibroepithelial Polyps." American Journal of Dermatopathology 21, no. 5 (October 1999): 446. http://dx.doi.org/10.1097/00000372-199910000-00007.

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Lewis, Kevan G., Lionel Bercovitch, Sara W. Dill, and Leslie Robinson-Bostom. "Acquired disorders of elastic tissue: part I. increased elastic tissue and solar elastotic syndromes." Journal of the American Academy of Dermatology 51, no. 1 (July 2004): 1–21. http://dx.doi.org/10.1016/j.jaad.2004.03.013.

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Krouskop, Thomas A., Thomas M. Wheeler, Faouzi Kallel, Brian S. Garra, and Timothy Hall. "Elastic Moduli of Breast and Prostate Tissues under Compression." Ultrasonic Imaging 20, no. 4 (October 1998): 260–74. http://dx.doi.org/10.1177/016173469802000403.

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To evaluate the dynamic range of tissue imaged by elastography, the mechanical behavior of breast and prostate tissue samples subject to compression loading has been investigated. A model for the loading was validated and used to guide the experimental design for data collection. The model allowed the use of small samples that could be considered homogeneous; this assumption was confirmed by histological analysis. The samples were tested at three strain rates to evaluate the viscoelastic nature of the material and determine the validity of modeling the tissue as an elastic material for the strain rates of interest. For loading frequencies above 1 Hz, the storage modulus accounted for over 93 percent of the complex modulus. The data show that breast fat tissue has a constant modulus over the strain range tested while the other tissues have a modulus that is dependent on the strain level. The fibrous tissue samples from the breast were found to be 1 to 2 orders of magnitude stiffer than fat tissue. Normal glandular breast tissue was found to have an elastic modulus similar to that of fat at low strain levels, but the modulus of the glandular tissue increased by an order of magnitude above fat at high strain levels. Carcinomas from the breast were stiffer than the other tissues at the higher strain level; intraductal in situ carcinomas were like fat at the low strain level and much stiffer than glandular tissue at the high strain level. Infiltrating ductal carcinomas were much stiffer than any of the other breast tissues. Normal prostate tissue has a modulus that is lower than the modulus of the prostate cancers tested. Tissue from prostate with benign prostatic hyperplasia (BPH) had modulus values significantly lower than normal tissue. There was a constant but not significant difference in the modulus of tissues taken from the anterior and posterior portions of the gland.

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Touw, Deborah M., M. H. Sherebrin, and Margot R. Roach. "The elastic properties of canine abdominal aorta at its branches." Canadian Journal of Physiology and Pharmacology 63, no. 11 (November 1, 1985): 1378–83. http://dx.doi.org/10.1139/y85-227.

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The elastic properties of the abdominal aorta at regions of junctions were studied using strips from 17 dogs. Strips of tissue cut longitudinally and circumferentially at the celiac, mesenteric, and renal branches were used to compare the properties of the proximal and distal junctions, as well as the aorta and artery regions adjoining. The tissues were stored for at least 24 h to ensure that no active component of the smooth muscle remained. The elastic properties measured here are due to elastin and collagen, with a small contribution from dead smooth muscle cells. The tissue strips were tested at 20 °C while immersed in saline using an Instron tensile testing machine. Elongation of the three regions was measured from photographs taken as the tissue was stretched. Stress values went to 200 kN/m2 as the strain increased to approximately 0.8. (The physiological range for the dog was calculated as 40–85 kN/m2.) The distal junctional region was found to be the most extensible for both longitudinally and circumferentially oriented strips. These results have important implications for flow models as they imply that the shape of the junctional region probably changes between diastole and systole.

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Lyshchik, A., T. Higashi, R. Asato, S. Tanaka, J. Ito, M. Hiraoka, A. B. Brill, T. Saga, and K. Togashi. "Elastic Moduli of Thyroid Tissues under Compression." Ultrasonic Imaging 27, no. 2 (April 2005): 101–10. http://dx.doi.org/10.1177/016173460502700204.

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The aim of this study was to evaluate the elastic moduli of thyroid tissues under uniaxial compression and to establish the biomechanical fundamentals for accurate interpretation of thyroid elastograms. A total of 67 thyroid samples (24 samples of normal thyroid tissue, 2 samples of thyroid tissue with chronic thyroiditis, 12 samples of adenomatous goiter lesions and 7 samples of follicular adenoma, 19 samples of papillary adenocarcinoma (PAC) and 3 samples of follicular adenocarcinoma (FAC)) obtained from 36 patients who had received thyroid surgery were subjected to biomechanical testing within three hours after surgical resection at precompression strains of 5%, 10% and 20% and applied strains of 1%, 2%, 5% and 10% of sample height. As a result, the mean values of elastic moduli for benign thyroid lesions at all examined precompression levels were significantly higher than those for normal thyroid tissue measured at the same load (p<0.01). At low precompression (5%) and compression (1–2%) levels, benign thyroid nodule samples were 1.7 times harder than normal thyroid tissue. At high precompression (20%) and compression (10%) levels, this difference increased to 2.4 times. Stiffness of PAC samples was significantly higher than those for normal thyroid tissue and benign thyroid tumors measured at the same load (p<0.01). At low precompression (5%) and compression (1–2%) levels, PAC samples were 5.0 times harder than normal thyroid tissue. At high precompression (20%) and compression (10%) levels, this difference increased to 17.7 times. In contrast, samples of FAC were much softer than PAC (p<0.05) and were comparable in stiffness to normal thyroid tissues. The significant differences in the stiffness between normal thyroid tissue and thyroid tumors may provide useful information for accurate interpretation of thyroid elastograms.

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Lillie, M. A., G. J. David, and J. M. Gosline. "Mechanical Role of Elastin-Associated Microfibrils in Pig Aortic Elastic Tissue." Connective Tissue Research 37, no. 1-2 (January 1998): 121–41. http://dx.doi.org/10.3109/03008209809028905.

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Cyril, Divya, Amelia Giugni, Saie Sunil Bangar, Melika Mirzaeipoueinak, Dipika Shrivastav, Mirit Sharabi, Joanne L. Tipper, and Javad Tavakoli. "Elastic Fibers in the Intervertebral Disc: From Form to Function and toward Regeneration." International Journal of Molecular Sciences 23, no. 16 (August 11, 2022): 8931. http://dx.doi.org/10.3390/ijms23168931.

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Despite extensive efforts over the past 40 years, there is still a significant gap in knowledge of the characteristics of elastic fibers in the intervertebral disc (IVD). More studies are required to clarify the potential contribution of elastic fibers to the IVD (healthy and diseased) function and recommend critical areas for future investigations. On the other hand, current IVD in-vitro models are not true reflections of the complex biological IVD tissue and the role of elastic fibers has often been ignored in developing relevant tissue-engineered scaffolds and realistic computational models. This has affected the progress of IVD studies (tissue engineering solutions, biomechanics, fundamental biology) and translation into clinical practice. Motivated by the current gap, the current review paper presents a comprehensive study (from the early 1980s to 2022) that explores the current understanding of structural (multi-scale hierarchy), biological (development and aging, elastin content, and cell-fiber interaction), and biomechanical properties of the IVD elastic fibers, and provides new insights into future investigations in this domain.

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Schwartz, E., and R. Fleischmajer. "Association of elastin with oxytalan fibers of the dermis and with extracellular microfibrils of cultured skin fibroblasts." Journal of Histochemistry & Cytochemistry 34, no. 8 (August 1986): 1063–68. http://dx.doi.org/10.1177/34.8.3525665.

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The formation of a mature elastic fiber is thought to proceed by the deposition of elastin on pre-existing microfibrils (10-12 nm in diameter). Immunohistochemical evidence has suggested that in developing tissues such as aorta and ligamentum nuchae, small amounts of elastin are associated with microfibrils but are not detected at the light microscopic and ultrastructural levels. Dermal tissue contains a complex elastic fiber system consisting of three types of fibers--oxytalan, elaunin, and elastic--which are believed to differ in their relative contents of microfibrils and elastin. According to ultrastructural analysis, oxytalan fibers contain only microfibrils, elaunin fibers contain small quantities of amorphous elastin, and elastic fibers are predominantly elastin. Using indirect immunofluorescence techniques, we demonstrate in this study that nonamorphous elastin is associated with the oxytalan fibers. Frozen sections of normal skin were incubated with antibodies directed against human aortic alpha elastin and against microfibrillar proteins isolated from cultured calf aortic smooth muscle cells. The antibodies to the microfibrillar proteins and elastin reacted strongly with the oxytalan fibers of the upper dermis. Oxytalan fibers therefore are composed of both microfibrils and small amounts of elastin. Elastin was demonstrated extracellularly in human skin fibroblasts in vitro by indirect immunofluorescence. The extracellular association of nonamorphous elastin and microfibrils on similar fibrils was visualized by immunoelectron microscopy. Treatment of these cultures with sodium dodecyl sulfate/mercaptoethanol (SDS/ME) solubilized tropoelastin and other proteins that reacted with the antibodies to the microfibrillar proteins. It was concluded that the association of the microfibrils with nonamorphous elastin in intact dermis and cultured human skin fibroblasts may represent the initial step in elastogenesis.

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Mercer, R. R., and J. D. Crapo. "Structural changes in elastic fibers after pancreatic elastase administration in hamsters." Journal of Applied Physiology 72, no. 4 (April 1, 1992): 1473–79. http://dx.doi.org/10.1152/jappl.1992.72.4.1473.

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Ultrastructural changes in lung parenchymal elastic fibers were studied morphometrically 1, 4, and 12 wk after a single 12-unit dose of pancreatic elastase and in a saline-instilled control group. The mean linear intercept of the parenchymal air spaces was increased in the 1-, 4-, and 12-wk post-elastase instillation groups compared with age-matched controls. The volume of alveolar connective tissue fibers predominantly composed of elastin (elastic fibers) was decreased by 35% 1 wk after the instillation of elastase but returned to control levels by 4 wk. Although the total volume of elastic fibers was normal 12 wk after instillation of elastase, the volume of elastic fibers in alveolar entrance rings remained significantly reduced. In serial sections of elastic fibers, numerous gaps or separations in the normally continuous band of elastic fibers that encircle each alveolus were identified 1 wk after elastase instillation. There were 169 +/- 8 (SE), 62 +/- 32, and 12 +/- 6 gaps per millimeter of alveolar entrance ring circumference at 1, 4, and 12 wk, respectively, in the elastase-treated groups. The number of gaps at 12 wk was equivalent to two gaps or discontinuities in the elastic fibers of every alveolar entrance ring. No gaps or separations in elastic fibers were detected at 1, 4, or 12 wk in the control groups. These defects occur in concordance with the progression of air space enlargement and presumably contribute to the progression of air space enlargement that occurs after the elastin content of the tissue has returned to normal.

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Morris, S. M., P. J. Stone, and G. L. Snider. "Electron microscopic study of human lung tissue after in vitro exposure to elastase." Journal of Histochemistry & Cytochemistry 41, no. 6 (June 1993): 851–66. http://dx.doi.org/10.1177/41.6.8315277.

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Much of the experimental evidence supporting the hypothesis that pulmonary emphysema results from an imbalance between elastases and anti-elastases in the lung comes from animal models. The present study was designed to examine the effects on human lung tissue of the two elastases that have been most widely used to produce these animal models. Lung tissue was exposed in vitro to human neutrophil elastase (HNE) or porcine pancreatic elastase (PPE). Although both enzymes solubilized protein at similar rates, PPE solubilized elastin five times faster than did HNE. Ultrastructurally, HNE-exposed tissue exhibited fewer damaged elastic fibers as well as some fibers that were damaged at the edges, whereas the interior of the fiber appeared intact. Elastic fibers showing damage only at the periphery were not seen in tissue exposed to PPE. Immunocytochemical studies in which antibodies to HNE and PPE were applied to thin sections of Lowicryl-embedded tissue indicated that both of these elastases could be detected in association with elastic fibers, but only in areas of the fiber that showed morphological evidence of elastase injury. Both HNE and PPE removed fibronectin from basement membranes (as determined by loss of binding of fibronectin antibodies after exposure to elastase), but neither elastase was detected on basement membrane. Loss of epithelial cells usually accompanied elastic fiber damage by HNE but not PPE.

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Gibson, Mark A., Jaliya S. Kumaratilake, and Edward G. Cleary. "Immunohistochemical and Ultrastructural Localization of MP78/70 (βig-h3) in Extracellular Matrix of Developing and Mature Bovine Tissues." Journal of Histochemistry & Cytochemistry 45, no. 12 (December 1997): 1683–96. http://dx.doi.org/10.1177/002215549704501212.

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MP78/70 is a matrix protein, with 78-kD and 70-kD isoforms, which was initially identified in bovine tissue extracts designed to solubilize elastin-associated microfibrils. Peptide analysis has shown that MP78/70 is closely related to the human protein, βig-h3. In the present study an antibody raised to a synthetic βig-h3 peptide was shown specifically to identify MP78/70 in purified form and in bovine tissue extracts. This is consistent with MP78/70 and βig-h3 being the bovine and human forms, respectively, of the same protein. The antibody was further affinity-purified on MP78/70 bound to Sepharose and used to localize the protein in a range of bovine tissues. Immunofluorescence showed that MP78/70 was localized to collagen fibers in tissues such as developing nuchal ligament, aorta and lung, and mature cornea; to reticular fibers in fetal spleen; and to capsule and tubule basement membranes in developing kidney. No general localization to elastic fibers was observed. The staining pattern in most tissues more closely resembled that of Type VI collagen, which occurs as collagen fiber-associated microfibrils, than that of fibrillin-1, a component of elastin-associated microfibrils. However, MP78/70 appeared to be less widely distributed than Type VI collagen. Immunoelectron microscopy showed that MP78/70 was predominantly found in loose association with collagen fibers in most tissues examined and was also located on the surface of the capsule basement membrane in developing kidney. Double labeling experiments indicated that MP78/70 is co-distributed with Type VI collagen microfibrils located in these regions. In some elastic tissues significant immunolabel was detected in regions of interface between collagen fibers and fibrillin-containing microfibrils of adjacent elastic fibers, and at the outer margins of the latter structures. Overall, the evidence points to MP78/70 having a bridging function, perhaps in association with Type VI collagen microfibrils, linking or stabilizing the interaction between interstitial collagen fibrils and other matrix structures, including some basement membranes and elastin-associated microfibrils.

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Nonaka, Risa, Takafumi Iesaki, Aurelien Kerever, and Eri Arikawa-Hirasawa. "Increased Risk of Aortic Dissection with Perlecan Deficiency." International Journal of Molecular Sciences 23, no. 1 (December 28, 2021): 315. http://dx.doi.org/10.3390/ijms23010315.

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Perlecan (HSPG2), a basement membrane-type heparan sulfate proteoglycan, has been implicated in the development of aortic tissue. However, its role in the development and maintenance of the aortic wall remains unknown. Perlecan-deficient mice (Hspg2−/−-Tg: Perl KO) have been found to show a high frequency (15–35%) of aortic dissection (AD). Herein, an analysis of the aortic wall of Perl KO mice revealed that perlecan deficiency caused thinner and partially torn elastic lamina. Compared to the control aortic tissue, perlecan-deficient aortic tissue showed a significant decrease in desmosine content and an increase in soluble tropoelastin levels, implying the presence of immature elastic fibers in Perl KO mice. Furthermore, the reduced expression of the smooth muscle cell contractile proteins actin and myosin in perlecan-deficient aortic tissue may explain the risk of AD. This study showed that a deficiency in perlecan, which is localized along the elastic lamina and at the interface between elastin and fibrillin-1, increased the risk of AD, largely due to the immaturity of extracellular matrix in the aortic tissue. Overall, we proposed a new model of AD that considers the deficiency of extracellular molecule perlecan as a risk factor.

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Elston, Dirk M., Martha L. McCollough, Karen E. Warschaw, and Wilma F. Bergfeld. "Elastic tissue in scars and alopecia." Journal of Cutaneous Pathology 27, no. 3 (March 2000): 147–52. http://dx.doi.org/10.1034/j.1600-0560.2000.027003147.x.

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Bouissou, Hubert, Marie-Thérèse Pieraggi, Monique Julian, and Thérèsa Savait. "The Elastic Tissue of the Skin." International Journal of Dermatology 27, no. 5 (June 1988): 327–35. http://dx.doi.org/10.1111/j.1365-4362.1988.tb02363.x.

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Feng, Gao, Ivan Djordjevic, Vishal Mogal, Richard O'Rorke, Oleksandr Pokholenko, and Terry W. J. Steele. "Elastic Light Tunable Tissue Adhesive Dendrimers." Macromolecular Bioscience 16, no. 7 (April 8, 2016): 1072–82. http://dx.doi.org/10.1002/mabi.201600033.

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Korte, Gary E. "The Elastic Tissue of Bruch's Membrane." Archives of Ophthalmology 107, no. 11 (November 1, 1989): 1654. http://dx.doi.org/10.1001/archopht.1989.01070020732037.

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Kim, Byung-Soo, and David J. Mooney. "Scaffolds for Engineering Smooth Muscle Under Cyclic Mechanical Strain Conditions." Journal of Biomechanical Engineering 122, no. 3 (February 6, 2000): 210–15. http://dx.doi.org/10.1115/1.429651.

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Cyclic mechanical strain has been demonstrated to enhance the development and function of engineered smooth muscle (SM) tissues, but appropriate scaffolds for engineering tissues under conditions of cyclic strain are currently lacking. These scaffolds must display elastic behavior, and be capable of inducing an appropriate smooth muscle cell (SMC) phenotype in response to mechanical signals. In this study, we have characterized several scaffold types commonly utilized in tissue engineering applications in order to select scaffolds that exhibit elastic properties under appropriate cyclic strain conditions. The ability of the scaffolds to promote an appropriate SMC phenotype in engineered SM tissues under cyclic strain conditions was subsequently analyzed. Poly(L-lactic acid)-bonded polyglycolide fiber-based scaffolds and type I collagen sponges exhibited partially elastic mechanical properties under cyclic strain conditions, although the synthetic polymer scaffolds demonstrated significant permanent deformation after extended times of cyclic strain application. SM tissues engineered with type I collagen sponges subjected to cyclic strain were found to contain more elastin than control tissues, and the SMCs in these tissues exhibited a contractile phenotype. In contrast, SMCs in control tissues exhibited a structure more consistent with the nondifferentiated, synthetic phenotype. These studies indicate the appropriate choice of a scaffold for engineering tissues in a mechanically dynamic environment is dependent on the time frame of the mechanical stimulation, and elastic scaffolds allow for mechanically directed control of cell phenotype in engineered tissues. [S0148-0731(00)00103-5]

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Lin, Ying-Ju, An-Ni Chen, Xi Jiang Yin, Chunxiang Li, and Chih-Chien Lin. "Human Microfibrillar-Associated Protein 4 (MFAP4) Gene Promoter: A TATA-Less Promoter That Is Regulated by Retinol and Coenzyme Q10 in Human Fibroblast Cells." International Journal of Molecular Sciences 21, no. 21 (November 9, 2020): 8392. http://dx.doi.org/10.3390/ijms21218392.

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Elastic fibers are one of the major structural components of the extracellular matrix (ECM) in human connective tissues. Among these fibers, microfibrillar-associated protein 4 (MFAP4) is one of the most important microfibril-associated glycoproteins. MFAP4 has been found to bind with elastin microfibrils and interact directly with fibrillin-1, and then aid in elastic fiber formation. However, the regulations of the human MFAP4 gene are not so clear. Therefore, in this study, we firstly aimed to analyze and identify the promoter region of the human MFAP4 gene. The results indicate that the human MFAP4 promoter is a TATA-less promoter with tissue- and species-specific properties. Moreover, the promoter can be up-regulated by retinol and coenzyme Q10 (coQ10) in Detroit 551 cells.

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Cocciolone, Austin J., Jie Z. Hawes, Marius C. Staiculescu, Elizabeth O. Johnson, Monzur Murshed, and Jessica E. Wagenseil. "Elastin, arterial mechanics, and cardiovascular disease." American Journal of Physiology-Heart and Circulatory Physiology 315, no. 2 (August 1, 2018): H189—H205. http://dx.doi.org/10.1152/ajpheart.00087.2018.

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Large, elastic arteries are composed of cells and a specialized extracellular matrix that provides reversible elasticity and strength. Elastin is the matrix protein responsible for this reversible elasticity that reduces the workload on the heart and dampens pulsatile flow in distal arteries. Here, we summarize the elastin protein biochemistry, self-association behavior, cross-linking process, and multistep elastic fiber assembly that provide large arteries with their unique mechanical properties. We present measures of passive arterial mechanics that depend on elastic fiber amounts and integrity such as the Windkessel effect, structural and material stiffness, and energy storage. We discuss supravalvular aortic stenosis and autosomal dominant cutis laxa-1, which are genetic disorders caused by mutations in the elastin gene. We present mouse models of supravalvular aortic stenosis, autosomal dominant cutis laxa-1, and graded elastin amounts that have been invaluable for understanding the role of elastin in arterial mechanics and cardiovascular disease. We summarize acquired diseases associated with elastic fiber defects, including hypertension and arterial stiffness, diabetes, obesity, atherosclerosis, calcification, and aneurysms and dissections. We mention animal models that have helped delineate the role of elastic fiber defects in these acquired diseases. We briefly summarize challenges and recent advances in generating functional elastic fibers in tissue-engineered arteries. We conclude with suggestions for future research and opportunities for therapeutic intervention in genetic and acquired elastinopathies.

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Golbad, Sara, and Mohammad Haghpanahi. "Hyperelastic Model Selection of Tissue Mimicking Phantom Undergoing Large Deformation and Finite Element Modeling for Elastic and Hyperelastic Material Properties." Advanced Materials Research 415-417 (December 2011): 2116–20. http://dx.doi.org/10.4028/www.scientific.net/amr.415-417.2116.

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Pathologies in soft tissues are associated with changes in their elastic properties. Tumor tissues are usually stiffer than the fat tissues and other normal tissues and show the nonlinear behavior in large deformations. There have been a lot of researches about elastography (linear and nonlinear) as a new detecting technique based on mechanical behavior of tissue. In order to formulate the tissue’s nonlinear behavior, a strain energy function is required. For better estimation of nonlinear tissue parameters in elasticity imaging, non linear stress-strain curve of phantom is used. This work presents hyperelastic measurement results of tissue-mimicking phantom undergoing large deformation during uniaxial compression. For phantom samples, 8 hyperelastic models have been used. The results indicate that polynomial model with N=2 is the most accurate in terms of fitting experimental data. To compare the results between elastic and hyperelastic model, a 3-D finite element numerical model developed based on two different materials of elastic and hyperelastic material properties. The comparison confirm the approach of other recent studies about necessity of hyperelastic elastography and state that hyperelastic elastography should be used to formulate a technique for breast cancer diagnosis.

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GIBBONS, CAROL A., and ROBERT E. SHADWICK. "Circulatory Mechanics in the Toad Bufo Marinus: I. Structure and Mechanical Design of the Aorta." Journal of Experimental Biology 158, no. 1 (July 1, 1991): 275–89. http://dx.doi.org/10.1242/jeb.158.1.275.

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This study describes several important mechanical design features of the aorta of a typical poikilothermic vertebrate. A strong functional similarity to the aorta of mammals is apparent, but some structural and mechanical differences are seen that reflect the lower pressure and simpler haemodynamics of the poikilothermic circulation. 1. The aorta is highly distensible, resilient and non-linearly elastic, giving it the requisite properties to act as an effective storage element in the arterial circulation. 2. An abrupt transition from high compliance (low elastic modulus) to relatively low compliance (high elastic modulus) takes place at pressures above the resting physiological range of 2–4 kPa. This behaviour reflects the composite nature of the artery wall in which rubbery elastin fibres and relatively rigid collagen fibres are the predominant elements. 3. The longitudinal tethering of the aorta when inflated is due primarily to anisotropy in elastic properties, rather than to links to the axial skeleton by branch vessels or connective tissue. 4. No significant changes in elastic properties or connective tissue content occur along the length of the toad arterial tree, in contrast to the situation in mammals.

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Hamandi, Farah, James T. Tsatalis, and Tarun Goswami. "Retrospective Evaluation and Framework Development of Bone Anisotropic Material Behavior Compared with Elastic, Elastic-Plastic, and Hyper-Elastic Properties." Bioengineering 9, no. 1 (December 29, 2021): 9. http://dx.doi.org/10.3390/bioengineering9010009.

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The main motivation for studying damage in bone tissue is to better understand how damage develops in the bone tissue and how it progresses. Such knowledge may help in the surgical aspects of joint replacement, fracture fixation or establishing the fracture tolerance of bones to prevent injury. Currently, there are no standards that create a realistic bone model with anisotropic material properties, although several protocols have been suggested. This study seeks to retrospectively evaluate the damage of bone tissue with respect to patient demography including age, gender, race, body mass index (BMI), height, and weight, and their role in causing fracture. Investigators believe that properties derived from CT imaging data to estimate the material properties of bone tissue provides more realistic models. Quantifying and associating damage with in vivo conditions will provide the required information to develop mathematical equations and procedures to predict the premature failure and potentially mitigate problems before they begin. Creating a realistic model for bone tissue can predict the premature failure(s), provide preliminary results before getting the surgery, and optimize the design of orthopaedic implants. A comparison was performed between the proposed model and previous efforts, where they used elastic, hyper- elastic, or elastic-plastic properties. Results showed that there was a significant difference between the anisotropic material properties of bone when compared with unrealistic previous methods. The results showed that the density is 50% higher in male subjects than female subjects. Additionally, the results showed that the density is 47.91% higher in Black subjects than Mixed subjects, 53.27% higher than Caucasian subjects and 57.41% higher than Asian. In general, race should be considered during modeling implants or suggesting therapeutic techniques.

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Sambani, Kyriaki, Stylianos Vasileios Kontomaris, and Dido Yova. "Atomic Force Microscopy Imaging of Elastin Nanofibers Self-Assembly." Materials 16, no. 12 (June 11, 2023): 4313. http://dx.doi.org/10.3390/ma16124313.

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Elastin is an extracellular matrix protein, providing elasticity to the organs, such as skin, blood vessels, lungs and elastic ligaments, presenting self-assembling ability to form elastic fibers. The elastin protein, as a component of elastin fibers, is one of the major proteins found in connective tissue and is responsible for the elasticity of tissues. It provides resilience to the human body, assembled as a continuous mesh of fibers that require to be deformed repetitively and reversibly. Thus, it is of great importance to investigate the development of the nanostructural surface of elastin-based biomaterials. The purpose of this research was to image the self-assembling process of elastin fiber structure under different experimental parameters such as suspension medium, elastin concentration, temperature of stock suspension and time interval after the preparation of the stock suspension. atomic force microscopy (AFM) was applied in order to investigate how different experimental parameters affected fiber development and morphology. The results demonstrated that through altering a number of experimental parameters, it was possible to affect the self-assembly procedure of elastin fibers from nanofibers and the formation of elastin nanostructured mesh consisting of naturally occurring fibers. Further clarification of the contribution of different parameters on fibril formation will enable the design and control of elastin-based nanobiomaterials with predetermined characteristics.

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Minin, Yuriy V., Pavlo A. Virych, Anton F. Karas, Svitlana P. Chaika, Halyna A. Karas, Nagiya S. Shuvalova, and Tetiana I. Kucherenko. "Regeneration of artificial injuries external ear elastic cartilage of rabbits after stem cells local injection." OTORHINOLARYNGOLOGY, No3-4(5) 2022 (July 29, 2022): 36–43. http://dx.doi.org/10.37219/2528-8253-2022-3-36.

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Introduction: Every year, a large number of patients from developed countries turn to surgical departments with the reconstruction problems of the auricle cartilage. A some of surgical procedures was developed to correct minor defects due to the low regenerative capacity of elastic cartilage. Stem cells can potentially differentiate into chondroblasts and chondrocytes and restore cartilage integrity. Many factors influence on the differentiation and proliferation of stem cells, which complicates the method application. Therefore, the investigation of using stem cells to regeneration elastic cartilage is relevant. Aim: clarification the regeneration features of the artificial defect of the rabbits’ ear elastic cartilage after the stem cells injection. Materials and methods: The investigation was conducted on rabbits of chinchilla breed aged 1.5 months, weighing 2.5 kg. Artificial lesions measuring 2 x 7-10 mm were simulated on the cartilaginous plate of the outer ear with a scalpel. 0.5 ml of stem cell suspension (~5 million) obtained from the umbilical cord of rabbits by enzymatic method was injected into the defect site. Histological sections of the cartilage defect were prepared. The samples were stained by Weigert and Azure II methods. The relative density of collagen, elastin fibers, oxyphilic and basophilic tissue elements was programmatically evaluated. Results and discussion: The amount of fibers in the native elastic cartilage was more on 35% of the relative dermis. The newly formed tissues at the damage cartilage was like to the dermis after 2 months. Similar results were found on ear in 2.5 and 3 months after surgery. Native cartilage on histological sections almost was not oxyphilic. Maybe a significant number of acidic components was masked it. Dense connective tissue contains almost equal amounts of both components. Thus, it is possible to trace changes in the intercellular matrix that will characterize the direction of the regeneration process. The area of elastic cartilage defect was characterized by a significant presence of oxyphilic elements after 2 months of the stem cells addition. The ratio of oxyphilic and basophilic components in the native elastic cartilage was about to zero. For the dermis was 1.4-1.5. Dense scar connective tissue was characterized by a ratio about 1. Based on the results obtained, was assumed that the direction of stem cell proliferation is determined shortly after injection. Conclusion: The addition of stem cells to the area of the artificially created elastic cartilage defect of the rabbit's ear was not allow to obtain stable regenerative processes of cartilage tissue and the restoration of the intercellular matrix to its original state. The process of stem cell differentiation contributes the formation of dense connective tissue of the scar, which may be due to the presence of proinflammatory cytokines, growth factors and other biologically active molecules. This was not creating the necessary conditions for the cartilage regeneration.

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Pugno, Nicola Maria, and Qiang Chen. "Modeling the Elastic Anisotropy of Woven Hierarchical Tissues: Experimental Comparison on Biological Materials and Design of a New Class of Scaffolds." Advances in Science and Technology 76 (October 2010): 153–58. http://dx.doi.org/10.4028/www.scientific.net/ast.76.153.

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This paper models the elastic properties of 2-D woven hierarchical tissues, assuming an orthotropic material of warp and fill yarns at level 0. Considering matrix transformation and stiffness averaging, stiffness matrices of warp and fill yarns of the tissue at level i are employed to calculate those of the tissue at level i+1. We compare our theory with another approach from the literature on tendons and experiments on leaves performed by ourselves. The result shows the possibility of designing a new class of hierarchical 2-D scaffolds with desired elastic anisotropy, better matching the anisotropy of the biological tissues and thus maximizing the regeneration.

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Zamir, Evan A., and Larry A. Taber. "On the Effects of Residual Stress in Microindentation Tests of Soft Tissue Structures." Journal of Biomechanical Engineering 126, no. 2 (April 1, 2004): 276–83. http://dx.doi.org/10.1115/1.1695573.

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Microindentation methods are commonly used to determine material properties of soft tissues at the cell or even sub-cellular level. In determining properties from force-displacement (FD) data, it is often assumed that the tissue is initially a stress-free, homogeneous, linear elastic half-space. Residual stress, however, can strongly influence such results. In this paper, we present a new microindentation method for determining both elastic properties and residual stress in soft tissues that, to a first approximation, can be regarded as a pre-stressed layer embedded in or adhered to an underlying relatively soft, elastic foundation. The effects of residual stress are shown using two linear elastic models that approximate specific biological structures. The first model is an axially loaded beam on a relatively soft, elastic foundation (i.e., stress-fiber embedded in cytoplasm), while the second is a radially loaded plate on a foundation (e.g., cell membrane or epithelium). To illustrate our method, we use a nonlinear finite element (FE) model and experimental FD and surface contour data to find elastic properties and residual stress in the early embryonic chick heart, which, in the region near the indenter tip, is approximated as an isotropic circular plate under tension on a foundation. It is shown that the deformation of the surface in a microindentation test can be used along with FD data to estimate material properties, as well as residual stress, in soft tissue structures that can be regarded as a plate under tension on an elastic foundation. This method may not be as useful, however, for structures that behave as a beam on a foundation.

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Kielty, Cay M., Simon Stephan, Michael J. Sherratt, Matthew Williamson, and C. Adrian Shuttleworth. "Applying elastic fibre biology in vascular tissue engineering." Philosophical Transactions of the Royal Society B: Biological Sciences 362, no. 1484 (June 22, 2007): 1293–312. http://dx.doi.org/10.1098/rstb.2007.2134.

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For the treatment of vascular disease, the major cause of death in Western society, there is an urgent need for tissue-engineered, biocompatible, small calibre artery substitutes that restore biological function. Vascular tissue engineering of such grafts involves the development of compliant synthetic or biomaterial scaffolds that incorporate vascular cells and extracellular matrix. Elastic fibres are major structural elements of arterial walls that can enhance vascular graft design and patency. In blood vessels, they endow vessels with the critical property of elastic recoil. They also influence vascular cell behaviour through direct interactions and by regulating growth factor activation. This review addresses physiological elastic fibre assembly and contributions to vessel structure and function, and how elastic fibre biology is now being exploited in small diameter vascular graft design.

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Rosenquist, T. H., and J. R. McCoy. "A new interpretation of the direct Schiff reaction of elastic connective tissue." Journal of Histochemistry & Cytochemistry 35, no. 11 (November 1987): 1205–15. http://dx.doi.org/10.1177/35.11.2443556.

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A direct Schiff reaction of elastic tissues has been known for many years, but the nature of the native aldehyde-rich components has not been clear. In this study, chicken, quail, and rat embryos and adult rat lung, aorta, and kidney were fixed in methacarn or in a formalin solution, embedded in paraffin, and sections of 8-10 micron obtained. Rehydrated sections were incubated for various periods in solutions of the enzymes chondroitinase ABC, clostripain, collagenase, elastase, heparatinase, hyaluronidase, subtilisin Carlsberg ("protease"), or trypsin, and in solutions of phosphomolybdic acid or sodium borohydride. After incubation, sections were placed, without prior oxidation, in Schiff's reagent, and were ultimately observed and photographed in transmitted light or with blue or green epifluorescence. A Schiff-positive substance was found, always and exclusively, in elastic tissues of the vasculature and lungs, which was hydrolyzed by the proteolytic enzymes to an extent that ranged from complete loss of Schiff reaction in minutes (trypsin) to no loss of Schiff reaction in 22 hr (clostripain). The Schiff-reactive protein preceded the time of appearance of elastin in the early embryos. We conclude that the aldehyde-rich protein responsible for this reaction is a harbinger of elastogenesis in vivo and speculate that it may represent the elastic microfibril or a component thereof.

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XIONG, Jiang, Wei GUO, Ren WEI, Shang-wei ZUO, Xiao-ping LIU, and Tao ZHANG. "Elastic fiber regeneration in vitro and in vivo for treatment of experimental abdominal aortic aneurysm." Chinese Medical Journal 126, no. 3 (February 2013): 437–41. http://dx.doi.org/10.3760/cma.j.issn.0366-6999.20122151.

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Background The pathological characteristics of abdominal aortic aneurysm (AAA) involved the regression of extracellular matrix (ECM) in aortic walls, especially elastic structure in medial layer. As the major structural protein of aorta, elastin contributes to the extensibility and elastic recoil of the vessels. We hypothesized that overexpression of elastin in vessel walls might regenerate the elastic structure of ECM, restore the elastic structure of the aneurysmal wall, and eventually lead to a reduction of aortic diameters (ADs) in an experimental model of AAA. Methods Tropoelastin (TE) of Sprague Dawley (SD) rat was synthesized by reverse transcription polymerase chain reaction and used to construct adneviral vectors containing elastin precursor protein (AdTE-GFP). Cultured vascular smooth muscle cells (VSMCs) from aortas of male SD rats were transfected with AdTE-GFP, AdGFP, adenoviral vector (AdNull), and phosphate buffered saline (PBS). Immunofluorescence staining was performed to determine the expression of elastin in transfected cells. The expression of elastic fibers in ECM of VSMCs transfected with AdTE-GFP were detected by fluorescence microscopy and transmission electron microscopy (TEM) at 1, 3, and 5 days following gene transfer. The AAA vessel walls were infused with AdTE-GFP or an empty AdNull, or PBS directly into the aneurysmal lumen. ADs of the aneurysms were compared in infused aortas. Formation of new elastic fibers in vivo was assessed by hematoxylin and eosin, and elastic von-Giesson staining. Recombinant elastin-GFP in vivo was identified by immunohistochemical staining. Results Elastic fibers were increased both in ECM of VSMC and in vessel walls after gene transfer. Histological studies revealed that the AdTE-GFP-transduced aortas had elastic fiber regeneration in the aneurysmal walls. The AdTE-GFP-transduced aortas showed a decreased AD (23.04%±14.49%, P<0.01) in AAA vessel walls. Conclusions Elastic fibers have been successfully overexpressed both in vitro and in a rat model of AAA by a technique of gene transfer. The overexpression of elastic fibers within the aneurysmal tissue appeared to reverse the aneurysm dilatation in this model.

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Hassler, Ove, and Sören Herbertsson. "ELASTASE TREATMENT OF FIXED ARTERIAL ELASTIC TISSUE." Acta Pathologica Microbiologica Scandinavica 55, no. 1 (August 18, 2009): 14–18. http://dx.doi.org/10.1111/j.1699-0463.1962.tb04092.x.

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Aessopos, A., D. Farmakis, and D. Loukopoulos. "Elastic tissue abnormalities in inherited haemolytic syndromes." European Journal of Clinical Investigation 32, no. 9 (September 2002): 640–42. http://dx.doi.org/10.1046/j.1365-2362.2002.01033.x.

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URRY, DAN W., and ASIMA PATTANAIK. "Elastic Protein-based Materials in Tissue Reconstructiona." Annals of the New York Academy of Sciences 831, no. 1 (December 17, 2006): 32–46. http://dx.doi.org/10.1111/j.1749-6632.1997.tb52182.x.

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Long, Jennifer L., and Robert T. Tranquillo. "Elastic fiber production in cardiovascular tissue-equivalents." Matrix Biology 22, no. 4 (June 2003): 339–50. http://dx.doi.org/10.1016/s0945-053x(03)00052-0.

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Damiano, V. V. "Neutrophil elastase and elastic tissue in emphysema." Journal of Clinical Pathology 42, no. 1 (January 1, 1989): 114–15. http://dx.doi.org/10.1136/jcp.42.1.114.

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Journal articles on the topic 'Elastic tissue'

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