Sun damages the elastic fibers and causes them to accumulate in abnormal arrangements.
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The skin itself atrophies (the dermis thins), there are fewer fibroblasts, mast cells and blood vessels and elastic fibers with aging.
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There are two layers of elastic fibers lining the inner and outer surfaces of the thick muscular wall of the artery.
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Synthetic track surfaces come in three types: polytrack (silica sand and fibers made of spandex, carpet, and rubber), tapes (sand and rubber), and cushion (sand, synthetic, and elastic fibers).
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It instead features a series of inflatable bellows surrounded by a fabric skin knitted from elastic fibers that move and flex along with the hand's motions as air is pumped in to create movement.
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"Vitamin C is an antioxidant that has proven to be helpful in fighting the effects of sun damage, the appearance of brown spots, and the breakdown of collagen," she says, while retinol is amazing at stimulating collagen, evening skin tone, and slowing down the breakdown of elastic fibers.
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An elastic stain photomicrograph at high power highlighting the elastic fibers in black. The elastic fibers will be highlighted by a Weigert or von Gieson elastic stains.
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The elastic fibers are often quite large and are easily identified. The elastic fibers are coarse, thick, and darkly eosinophilic, often fragmented into globules, creating a "string of pearls" or "pipe cleaner" appearance. Because of degeneration, the elastic fibers will appear as globules with a serrated or "prickled" edge.
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These molecules interact to form the elastic fibers in the ventricularis layer of the semilunar valves. Fibrillin-1 and fibrillin-2 are also crucial for the development of elastic fibers in the aorta. While expression of fibrillin-2 decreases significantly after fetal development, the expression of fibrillin-1 continues into adulthood. This supports the idea that fibrilin-2 dictates the development of early elastic fibers, while fibrillin-1 provides the structural support of mature elastic fibers.
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Blue coloured elastic fibers Weigert's elastic stain is a combination of stains used in histology which is useful in identifying elastic fibers. Often orcein or a combination of resorcinol and fuchsine are used for staining. For counterstaining cell nuclei nuclear fast red or hematoxylin is also used. After applying elastic fibers show up blue coloured while cell nuclei gets red or blue.
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Elastic fibers are found in the skin, lungs, arteries, veins, connective tissue proper, elastic cartilage, periodontal ligament, fetal tissue and other structures. Elastic fibers are absent from scarring, keloids and dermatofibromas and they are decreased greatly, or are absent in anetodermas.
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The elastic matrix forms lamellae, consisting of elastic fibers, collagens (predominately type III), proteoglycans, and glycoaminoglycans.
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Deficiency causes Classical-like Ehlers–Danlos syndrome, where collagen density is reduced and elastic fibers are fragmentated.
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Elastofibroma, is an ill-defined fibroelastic tumor-like condition made up of enlarged and irregular elastic fibers.
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The middle coat is composed of a thick layer of connective tissue with elastic fibers, intermixed, in some veins, with a transverse layer of muscular tissue. The white fibrous element is in considerable excess, and the elastic fibers are in much smaller proportion in the veins than in the arteries.
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Elastic fibers (or yellow fibers) are bundles of proteins (elastin) found in extracellular matrix of connective tissue and produced by fibroblasts and smooth muscle cells in arteries. These fibers can stretch up to 1.5 times their length, and snap back to their original length when relaxed. Elastic fibers include elastin, elaunin and oxytalan. Elastic tissue is classified as "connective tissue proper".
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Elastic fibers stain well with aldehyde fuchsin, orcein, and Weigert's elastic stain in histological sections. The permanganate-bisulfite-toluidine blue reaction is a highly selective and sensitive method for demonstrating elastic fibers under polarizing optics. The induced birefringence demonstrates the highly ordered molecular structure of the elastin molecules in the elastic fiber. This is not readily apparent under normal optics.
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Reinke F. Zellstudien. Archiv Microsc Anat. 1894;43:377–422. Specifically, he investigated leukocytes, the cells of the conjunctive tissue, collagenous and elastic fibers, pigment, and cell differentiation.
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URL: . Accessed on: January 2, 2013. Elastic fibers and cell nuclei are stained black, collagen fibers are stained red, and other tissue elements including cytoplasm are stained yellow.
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Fibroblasts make collagen fibres, glycosaminoglycans, reticular and elastic fibers. Growing individuals' fibroblasts are dividing and are synthesizing ground substance. Tissue damage stimulates fibrocytes and induces the production of fibroblasts.
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Pages 1, 11–12. . The dermis is tightly connected to the epidermis through a basement membrane. Structural components of the dermis are collagen, elastic fibers, and extrafibrillar matrix.Marks, James G; Miller, Jeffery (2006).
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In sheath arrangement collagen bundles and matrix are distributed in irregular patterns, sometimes in the form of a network. It is similar to areolar tissue, but in DRCT elastic fibers are completely absent.
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Their mantle contains a layer of muscle sandwiched between elastic fibers. The muscle fibers run around the bell circumferentially while the elastic fibers run through the muscle and along the sides of the bell to prevent lengthening. After making a single contraction, the bell vibrates passively at the resonant frequency to refill the bell. However, in contrast with scallops, the inertial work is similar to the hydrodynamic work due to how medusas expel water - through a large opening at low velocity.
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They also contain a number of elastic fibers, which render them firmer and more elastic than the other types of papillae. The larger and longer papillae of this group are sometimes termed papillae conicae.
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The FBN-1 gene is involved in a variety of embryonic developmental programs. The microfibrils that are made from fibrillin-1 contribute to both elastic and non-elastic structures. The formation of the elastic fibers in the heart valves and the aorta require the involvement of both FBN-1 and FBN-2. It has been shown that both FBN-1 and FBN-2, along with the other components of elastic fibers, are expressed in the embryonic semilunar valves as early as 4 weeks of gestation.
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Compression stockings are constructed using elastic fibers or rubber. These fibers help compress the limb, aiding in circulation. Compression stockings are offered in different levels of compression. The unit of measure used to classify the pressure of the stockings is mmHg.
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GM1-gangliosidosis is a lysosomal storage disease that can be caused by a deficiency of β-galactosidase (GLB1). Some cases of Morquio syndrome B have been shown to be due to GLP1 mutations that cause patients to have abnormal elastic fibers.
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Pleural pressure is the pressure in the pleural space. When this pressure is lower than the pressure of alveoli they tend to expand. This prevents the elastic fibers and outside pressure from crushing the lungs. It is a homeostatic mechanism.
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Tendons attach skeletal muscles to bones; ligaments connect bones to bones at joints. Ligaments are more stretchy and contain more elastic fibers than tendons. Dense connective tissue also make up the lower layers of the skin (dermis), where it is arranged in sheets.
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Thickest portion of capsule is annular region surrounding the anterior pole. This will also increases with age (from 13.5-16μm). Even though capsule is a highly elastic structure, it contains no elastic fibers. Elasticity is because of the thick lamellar arrangement of the collagen fibers.
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In: Fitzpatick TB, Eisen AZ, Wolff K, Freedberg IM, Austen KF (eds.): Dermatology in General Medicine, Vol. II. New York, NY: McGraw-Hill, Inc.; 1993:2972-2970Uitto J, Fazio MJ, Olsen DR: Cutaneous aging: Molecular alterations in elastic fibers. J Cuta Aging & Cos Derm 1(1):13-26, 1998.
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Not to confuse with Fibrin Fibrillin is a glycoprotein, which is essential for the formation of elastic fibers found in connective tissue. Fibrillin is secreted into the extracellular matrix by fibroblasts and becomes incorporated into the insoluble microfibrils, which appear to provide a scaffold for deposition of elastin.
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The collagen fibers are loose and dispersed, and the elastic fibers are always fragmented. However, the epidermis is not affected. Although some patients present clinical features similar to those of progeria and metageria, they do not usually show generalized atherosclerosis. Therefore, they do not usually have premature myocardiac or coronary disease.
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Small full thickness wounds under 2mm reepithelize fast and heal scar free. Deep second- degree burns heal with scarring and hair loss. Sweat glands do not form in scar tissue, which impairs the regulation of body temperature. Elastic fibers are generally not detected in scar tissue younger than 3 months old.
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Verhoeff's stain, also known as Verhoeff's elastic stain (VEG) or Verhoeff–Van Gieson stain (VVG),Verhoeff-Van Gieson (VVG) Staining Protocol for Elastic Fibers. IHC World. URL: . Accessed on: January 2, 2013. is a staining protocol used in histology, developed by American ophthalmic surgeon and pathologist Frederick Herman Verhoeff (1874–1968) in 1908.
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Fibulin (FY-beau-lin) (now known as Fibulin-1 FBLN1) is the prototypic member of a multigene family, currently with seven members. Fibulin-1 is a calcium- binding glycoprotein. In vertebrates, fibulin-1 is found in blood and extracellular matrices. In the extracellular matrix, fibulin-1 associates with basement membranes and elastic fibers.
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The SLP has fewer elastic and collagenous fibers than the two other layers, and thus is looser and more pliable. The ILP is mostly composed of elastic fibers, while the DLP has fewer elastic fibers, and more collagenous fibers. In those two layers, which form what is known as the vocalis ligament, the elastic and collagenous fibers are densely packed as bundles that run almost parallel to the edge of the vocal fold. There is a steady increase in the elastin content of the lamina propria as humans age (elastin is a yellow scleroprotein, the essential constituent of the elastic connective tissue) resulting in a decrease in the ability of the lamina propria to expand caused by cross-branching of the elastin fibers.
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The alveolar septum separates adjacent alveoli in lung tissue. The minimal components of an alveolar septum consist of the basement membranes of alveolar-lining epithelium (mostly type I pneumocytes) and capillary endothelium. Thicker alveolar septa may also contain elastic fibers, type I collagen, interstitial cells, smooth muscle cells, mast cells, lymphocytes and also monocytes.
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The ELN gene encodes a protein that is one of the two components of elastic fibers. The encoded protein is rich in hydrophobic amino acids such as glycine and proline, which form mobile hydrophobic regions bounded by crosslinks between lysine residues. Multiple transcript variants encoding different isoforms have been found for this gene. Elastin's soluble precursor is tropoelastin.
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Pseudoxanthoma elasticum (PXE) is a genetic disease that causes mineralization of elastic fibers in some tissues. The most common problems arise in the skin and eyes, and later in blood vessels in the form of premature atherosclerosis. PXE is caused by autosomal recessive mutations in the ABCC6 gene on the short arm of chromosome 16 (16p13.1).
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In 1962, he founded his own firm, which was dedicated to the design and production of women's lingerie and later expanded into swimwear. He is known for being the first designer to incorporate elastic fibers into their designs. The firm currently has collections under three brands: Andrés Sardá, Risk, and University. His daughter, Nuria Sardá, is also a collaborator with his company.
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It has been suggested that myofibroblasts also reside in the lamina propria of several organs. These cells have characteristics of both smooth muscle and fibroblasts. The lamina propria may also be rich in vascular networks, lymphatic vessels, elastic fibers, and smooth muscle fascicles from the muscularis mucosae. Afferent and efferent nerve endings can be found in the lamina propria as well.
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Bruch's membrane consists of five layers (from inside to outside):eOptha website: Anatomy of Uvea by Parthopratim Dutta Majumder #the basement membrane of the retinal pigment epithelium #the inner collagenous zone #a central band of elastic fibers #the outer collagenous zone #the basement membrane of the choriocapillaris The retinal pigment epithelium transports metabolic waste from the photoreceptors across Bruch's membrane to the choroid.
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In the alveolar walls there are interconnecting air passages between the alveoli known as the pores of Kohn. The alveolar septa that separate the alveoli in the alveolar sac contain some collagen fibers and elastic fibers. The septa also house the enmeshed capillary network that surrounds each alveolus. The elastic fibres allow the alveoli to stretch when they fill with air during inhalation.
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"Vicious cycle" theory of the pathogenesis of bronchiectasis. The development of bronchiectasis requires two factors: an infectious insult and impaired drainage, obstruction, or a defect in host defense. This triggers a host immune response from neutrophils (elastases), reactive oxygen species, and inflammatory cytokines that results in progressive destruction of normal lung architecture. In particular, the elastic fibers of bronchi are affected.
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Because these ligaments lie in the posterior part of the vertebral canal, their hypertrophy can cause spinal stenosis, particularly in patients with diffuse idiopathic skeletal hyperostosis. Some studies indicate that the hypertrophy of these ligaments may be linked to a fibrotic process associated with increased collagen VI, which could represent an adaptive and reparative process in response to the rupture of elastic fibers.
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In general, the tumor is an ill defined, nonencapsulated, rubbery, and firm, white lesion with interspersed fat. The tumors can be quite large (up to 20 cm), although most are around 5 cm.A high power photomicrograph of an elastofibroma. By microscopie view, there is an admixture of heavy dense bands of collagenous tissue dissected by fat and abnormal elastic fibers.
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The reticular dermis is the lower layer of the dermis, found under the papillary dermis, composed of dense irregular connective tissue featuring densely packed collagen fibers. It is the primary location of dermal elastic fibers. The reticular region is usually much thicker than the overlying papillary dermis. It receives its name from the dense concentration of collagenous, elastic, and reticular fibers that weave throughout it.
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The mechanism behind cardiac fibromas is still unclear. Fibromas have a homogeneous mass of fibroblasts mixed with an abundance of collagen and elastic fibers. These masses represent mesenchymal growth, but lack other mesenchymal elements, such as blood vessels, cartilage bone, and muscle. These masses often entrap cardiomyocytes, which are muscle cells that make up the cardiac muscle; cells decrease while collagen content increase in these masses.
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The S-Gal protein functions during the normal assembly of elastin into extracellular elastic fibers. Elastin is initially present as newly synthesized tropoelastin which can be found in association with S-Gal. The enzymatic activity of neuraminidase in the elastin receptor complex is involved in the release of tropoelastin molecules from the S-Gal chaperone. Cathepsin A is also required for normal elastin biosynthesis.
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The elastic fibers remained sparse and immature during infancy, mostly made of microfibrils. The fibroblasts in the infant Reinke's space were still sparse but spindle-shaped. Their rough endoplasmic reticulum and Golgi apparatus were still not well developed, indicating that despite the change in shape, the fibroblasts still remained mostly in a resting phase. Few newly released materials were seen adjacent to the fibroblasts.
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Link proteins such as vinculin, spectrin and actomyosin stabilize the proteoglycans and organize elastic fibers in the ECM. Changes in the density of ground substance can allow collagen fibers to form aberrant cross-links. Loose connective tissue is characterized by few fibers and cells, and a relatively large amount of ground substance. Dense connective tissue has a smaller amount of ground substance compared to the fibrous material.
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At the microscopic level, NSF shows a proliferation of dermal fibroblasts and dendritic cells, thickened collagen bundles, increased elastic fibers, and deposits of mucin. More recent case reports have described the presence of sclerotic bodies (also known as elastocollagenous balls) in skin biopsies from NSF patients. While not universally present, this finding is believed to be unique to patients exposed to gadolinium, although not necessarily limited to areas involved by NSF.
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1,4-Butanediol is used industrially as a solvent and in the manufacture of some types of plastics, elastic fibers and polyurethanes. In organic chemistry, 1,4-butanediol is used for the synthesis of γ-butyrolactone (GBL). In the presence of phosphoric acid and high temperature, it dehydrates to the important solvent tetrahydrofuran. At about 200 °C in the presence of soluble ruthenium catalysts, the diol undergoes dehydrogenation to form butyrolactone.
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Wrinkles on the face and hands are a typical sign of aging Development of facial wrinkles is a kind of fibrosis of the skin. Misrepair-accumulation aging theory suggests that wrinkles develop from incorrect repairs of injured elastic fibers and collagen fibers. Repeated extensions and compressions of the skin cause repeated injuries of extracellular fibers in derma. During the repairing process, some of the broken elastic fibers and collagen fibers are not regenerated and restored but replaced by altered fibers. When an elastic fiber is broken in an extended state, it may be replaced by a “long” collagen fiber. Accumulation of “long” collagen fibers makes part of the skin looser and stiffer, and as a consequence, a big fold of skin appears. When a “long” collagen is broken in a compressed state, it may be replaced by a “short” collagen fiber. The “shorter” collagen fibers will restrict the extension of "longer" fibers, and make the “long” fibers in a folding state permanently.
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Accessed on: January 2, 2013.Verhoeff's Stain. Merriam-Webster. URL: . Accessed on: January 2, 2013. The formulation is used to demonstrate normal or pathologic elastic fibers. Verhoeff's stain forms a variety of cationic, anionic and non-ionic bonds with elastin, the main constituent of elastic fiber tissue. Elastin has a strong affinity for the iron-hematoxylin complex formed by the reagents in the stain and will hence retain dye longer than other tissue elements.
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This is called peau d'orange (a French term meaning "skin of the orange"). Eventually the mineralization of the elastic fibers in the Bruch membrane create cracks called angioid streaks that radiate out from the optic nerve. Angioid streaks themselves do not cause distortion of vision, even if they cross into the foveal area. This symptom is present in almost all PXE patients and is usually noticed a few years after the onset of cutaneous lesions.
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The epithelium starts as a simple ciliated columnar epithelium and changes to simple ciliated cuboidal epithelium as the bronchioles decreases in size. The diameter of the bronchioles is often said to be less than 1 mm, though this value can range from 5 mm to 0.3 mm. As stated, these bronchioles do not have hyaline cartilage to maintain their patency. Instead, they rely on elastic fibers attached to the surrounding lung tissue for support.
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Hendon helped to improve and guide ablation treatment of atrial fibrillation using a near-infrared spectroscopy (NIRS) guided catheter implantation. Her results showed improved results of radio-frequency ablation therapy. Hendon then used her knowledge and expertise in OCT to characterize the structure-function relationship of heart tissue. She showed that she was able to image, with high resolution, elastic fibers, Purkinje fibers, and collagen fiber bundles, as well as observe tissue pathology.
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Elastic recoil is inversely related to lung compliance. This phenomenon occurs because of the elastin in the elastic fibers in the connective tissue of the lungs, and because of the surface tension of the film of fluid that lines the alveoli. As water molecules pull together, they also pull on the alveolar walls causing the alveoli to recoil and become smaller. But two factors prevent the lungs from collapsing: surfactant and the intrapleural pressure.
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When pressure is greater inside the lymphatic capillary, the cells adhere more closely, and lymph cannot escape back into interstitial fluid. Attached to the lymphatic capillaries are anchoring filaments, which contain elastic fibers. They extend out from the lymphatic capillary, attaching lymphatic endothelial cells to surrounding tissues. When excess interstitial fluid accumulates and causes tissue swelling, the anchoring filaments are pulled, making the openings between cells even larger so that more fluid can flow into the lymphatic capillary.
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Schematic representation of the composition of loose connective tissue It is a pliable, mesh-like tissue with a fluid matrix and functions to cushion and protect body organs. Fibroblasts are widely dispersed in this tissue; they are irregular branching cells that secrete strong fibrous proteins and proteoglycans as an extracellular matrix. The cells of this type of tissue are generally connected by a gelatinous substance known as ground substance primarily made up of collagenous and elastic fibers.
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Many adjacent epithelial tissues (which are avascular) get their nutrients from the interstitial fluid of areolar tissue; the lamina propria is areolar in many body locations. Its fibers run in random directions and are mostly collagenous, but elastic and reticular fibers are also present. Areolar tissue is highly variable in appearance. In many serous membranes, it appears as a loose arrangement of collagenous and elastic fibers, scattered cells of various types; abundant ground substance; numerous blood vessels.
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Gopchang (Hangul: ) can refer to the small intestines of cattle (or big intestines of pig) or to a gui (grilled dish) made of the small intestines. The latter is also called gopchang-gui (; "grilled intestines"). The tube- shaped offal is chewy with rich elastic fibers. In Korean cuisine, it is stewed in a hot pot (gopchang-jeongol, 곱창전골), grilled over a barbecue (gopchang-gui), boiled in soup with other intestines (naejang-tang), or made into a sausage (sundae).
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Structural components of the dermis are collagen, elastic fibers, and ground substance. Within these components are the pilosebaceous units, arrector pili muscles, and the eccrine and apocrine glands. The dermis contains two vascular networks that run parallel to the skin surface—one superficial and one deep plexus—which are connected by vertical communicating vessels. The function of blood vessels within the dermis is fourfold: to supply nutrition, to regulate temperature, to modulate inflammation, and to participate in wound healing.
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The intermediate layer of the lamina propria is primarily made up of elastic fibers while the deep layer of the lamina propria is primarily made up of collagenous fibers. These fibers run roughly parallel to the vocal fold edge and these two layers of the lamina propria comprise the vocal ligament. The transition layer is primarily structural, giving the vocal fold support as well as providing adhesion between the mucosa, or cover, and the body, the thyroarytenoid muscle.
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When mutations in the FBN-1 or FBN-2 genes occur, significant deformations can result from the damage to the extracellular matrix. Marfan Syndrome is a congenital disease that arises from a mutation in the FBN-1 gene. This leads to the malformation and subsequent weakening of the microfibrils in the patient’s body, including the structures of the cardiovascular system. The weakened elastic fibers will result in an impaired durability and distensibility in the heart valves and aorta.
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Newborns have a uniform monolayered lamina propria, which appears loose with no vocal ligament. The monolayered lamina propria is composed of ground substances such as hyaluronic acid and fibronectin, fibroblasts, elastic fibers, and collagenous fibers. While the fibrous components are sparse, making the lamina propria structure loose, the hyaluronic acid (HA) content is high. HA is a bulky, negatively charged glycosaminoglycan, whose strong affinity with water procures HA its viscoelastic and shock absorbing properties essential to vocal biomechanics.
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Syphilitic aortitis is inflammation of the aorta associated with the tertiary stage of syphilis infection. SA begins as inflammation of the outermost layer of the blood vessel, including the blood vessels that supply the aorta itself with blood, the vasa vasorum. As SA worsens, the vasa vasorum undergo hyperplastic thickening of their walls thereby restricting blood flow and causing ischemia of the outer two-thirds of the aortic wall. Starved for oxygen and nutrients, elastic fibers become patchy and smooth muscle cells die.
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The dermis is the layer of skin between the epidermis and subcutaneous tissue, and comprises two sections, the papillary dermis and the reticular dermis. The superficial papillary dermis interdigitates with the overlying rete ridges of the epidermis, between which the two layers interact through the basement membrane zone. Structural components of the dermis are collagen, elastic fibers, and ground substance also called extra fibrillar matrix. Within these components are the pilosebaceous units, arrector pili muscles, and the eccrine and apocrine glands.
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Copperhead's contortionist skills allow him to fit himself into incredibly small spaces (such as chimneys). He originally wore a snake-themed costume. The suit was a weave of metallic and elastic fibers and covered vulnerable points (such as the chest) with Kevlar, making it bulletproof and impenetrable to almost any cutting edged weapon. The costume had been treated with a highly slippery water- and heat-proof silicon gel, allowing Copperhead to slide along any surface and slip out of tight spots.
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It also surrounds the blood vessels and nerves. Cells called fibroblasts are widely dispersed in this tissue; they are irregular branching cells that secrete strong fibrous proteins and proteoglycans as an extracellular matrix. The cells of this type of tissue are generally separated by quite some distance by a gelatinous substance primarily made up of collagenous and elastic fibers. Usually "loose connective tissue" is considered a parent category that includes the mucous connective tissue of the fetus, areolar connective tissue, reticular connective tissue, and adipose tissue.
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Muscle is stained blue-black to dark brown, connective tissue is pale orange-pink to brownish red, fibrin and neuroglia stain deep blue, coarse elastic fibers show as purple, and bone and cartilage obtain yellowish to brownish red color. PTAH is ideal for demonstrating striated muscle fibers and mitochondria, often without a counterstain. As such, it is used to identify contraction bands, as seen in contraction band necrosis. PTAH stains ependymomas while it does not stain choroid plexus papillomas, providing one means of differentiating these tumors.
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A. Blanton (Personal Communication, March 11, 2009). The superficial layer of the lamina propria is a structure that vibrates a great deal during phonation, and the viscoelasticity needed to support this vibratory function depends mostly on extracellular matrices. The primary extracellular matrices of the vocal fold cover are reticular, collagenous and elastic fibers, as well as glycoprotein and glycosaminoglycan. These fibers serve as scaffolds for structural maintenance, providing tensile strength and resilience so that the vocal folds may vibrate freely but still retain their shape.
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Skeleton The barndoor skate is a flat-bodied fish with a large, disk-like body with sharply angled corners and a pointed snout. Its pectoral fins have evolved into broad, flat, wing-like appendages used to propel the fish through the water. These fins have a concave front edge with rounded posterior corners. Like sharks, it has a boneless skeleton made of cartilage, a tough, elastic substance composed of collagenous and/or elastic fibers, cells, and a firm, gel-like substance called the matrix.
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Principally used as a nuclear stain (to stain the cell nucleus), haematoxylin will also stain rough endoplasmic reticulum, ribosomes, collagen, myelin, elastic fibers, and acid mucins. Haematoxylin alone is not an effective stain, but when oxidized to hematein, and combined with a mordant, stains chromatin in cell nuclei dark blue to black. The colour and specificity of haematoxylin stains are controlled by the chemical nature, and amount, of the mordant used, and the pH of the staining solution, thus, a variety of haematoxylin formulations have been developed.
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Because the physical properties of skin rely heavily on the structural proteins of the elastic fiber system of epidermal cells, abnormal glycosylation can lead to structural defects in the elastic fibers, and therefore lead to the inelastic skin seen in WSS. WSS patients may also have defective secretion of another ECM component of the skin called tropoelastin.Hucthagowder V, Morava E, Kornak U, et al. Loss-of-function mutations in ATP6V0A2 impair vesicular trafficking, tropoelastin secretion and cell survival. Hum Mol Genet. 2009;18(12):2149–2165.
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Certain mutations in the MYLK gene are associated with thoracic aortic aneurysms or thoracic aortic dissections. This disease is caused by mutations affecting the gene MYLK. A disease characterized by permanent dilation of the thoracic aorta usually due to degenerative changes in the aortic wall. It is primarily associated with a characteristic histologic appearance known as 'medial necrosis' or 'Erdheim cystic medial necrosis' in which there is degeneration and fragmentation of elastic fibers, loss of smooth muscle cells, and an accumulation of basophilic ground substance.
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Myxomatous degeneration of the aortic valve, common in Marfan syndrome Heritable connective tissue diseases are rare, each disorder estimated at one to ten per 100,000, of which Marfan syndrome is the most common. It is carried by the FBN1 gene on chromosome 15, which encodes the connective protein fibrillin-1, inherited as a dominant trait. This protein is essential for synthesis and maintenance of elastic fibers. Since these fibers are particularly abundant in the aorta, ligaments, and the ciliary zonules of the eye, these areas are among the worst affected.
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Transforming growth factor beta (TGF-β) plays an important role in MFS. Fibrillin-1 directly binds a latent form of TGF-β, keeping it sequestered and unable to exert its biological activity. The simplest model suggests reduced levels of fibrillin-1 allow TGF-β levels to rise due to inadequate sequestration. Although how elevated TGF-β levels are responsible for the specific pathology seen with the disease is not proven, an inflammatory reaction releasing proteases that slowly degrade the elastic fibers and other components of the extracellular matrix is known to occur.
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On light microscope examination, these fibres may be distinguished from mature elastic fibers by their failure to stain with aldehyde fuchsin solutions, unless they have been oxidized by potassium permanganate, performic acid or peracetic acid. Under electron microscopy they appear to be composed of microfibrillar units, 7–20 nm in diameter with a periodicity of 12–17 nm. From their morphology, localization and staining properties it seems likely that these fibers are an immature form of elastic tissue. They can be found on the surface of smooth muscles.
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They were first described by Robert Walter Doyne in 1889 in a patient with retinal hemorrhages. In 1892, ophthalmologist Hermann Jakob Knapp called them "angioid streaks" because of their resemblance to blood vessels. From histopathological research in the 1930s, they were discovered to be caused by changes at the level of Bruch's membrane. Presently, it is believed that its pathology may be a combination of elastic degeneration of Bruch's membrane, iron deposition in elastic fibers from hemolysis with secondary mineralization, and impaired nutrition due to stasis and small vessel occlusion.
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This bulge is the result of the creation of a false lumen due to the vast amount of blood seepage from the aortas and surrounding veins. In some cases it is not uncommon to see degeneration in the ascending and descending aorta and the atrioventricular and semilunar valves due to elastolysis or breakdown and loss of elastic fibers. These connective tissue malfunctions are traceable to mutations, and lack of genes encoding for important components such as collagens, and micro- fibril-associated glycoproteins. Breakdown among these connective layers eventually compromises the integrity of the aortic lumen.
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Coacervation must occur outside of the cell within the ECM ( the ECM has a more alkaline environment than the vesicle) for proper elastic fiber assembly. However, defective ATP6V0A2 pumps in the vesicle increase the lumenal pH of the vesicle, leading to premature coacervation and defective elastic fiber assembly. The abnormal assembly and glycosylation of proteins used to make elastic fibers explains the connective tissue phenotypes associated with ARCL2 and WSS but does not explain the neurodevelopmental disorders or growth defects of these patients (18). Elastin is not required for brain or bone growth.
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Among other things, this leads to the mature voice being better suited to the rigors of opera. The extracellular matrix of the VF LP is composed of fibrous proteins such as collagen and elastin, and interstitial molecules such as HA, a non- sulfated glycosaminoglycan. While the SLP is rather poor in elastic and collagenous fibers, the ILP and DLP are mostly composed of it, with the concentration of elastic fibers decreasing and the concentration of collagenous fibers increasing as the vocalis muscle is approached. Fibrous proteins and interstitial molecules play different roles within the ECM.
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High blood pressure in the long term can damage the endothelium, commonly known as the blood vessel lining. This leads to a build-up of plaques and they can be deposited in the renal arteries causing stenosis and ischemic kidney disease. In this situation, the kidney supplied blood by the narrowed renal artery suffers from inadequate blood flow, which in turn causes the size of the kidneys to decrease. Other consequences include arterial stiffening, which involves a gradual breakdown of elastic fibers and intima (the innermost layer of a blood vessel) thickening.
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The term "endocardial fibroelastosis" was introduced by Weinberg and Himmelfarb in 1943. In their pathology laboratory they noted that usually the endocardium was pearly white or opaque instead of normally thin and transparent and microscopically showed a systematic layering of collagenous and elastic fibers. They felt their new term was more adequately descriptive, and, indeed it was quickly and widely adopted. Clinicians began applying it to any infant with a dilated, failing heart, in spite of the fact that the only way to definitively establish the presence of EFE was to see it at autopsy.
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Therapeutic efficacy of intravenous injection of human bone marrow-Muse cells into a SCID mouse aortic aneurysm model was evaluated. At 8 weeks, infusion of human Muse cells attenuated aneurysm dilation, and the aneurysmal size in the Muse group corresponded to approximately 45.6% in the vehicle group. Infused Muse cells were shown to migrate into aneurysmal tissue from the adventitial side and penetrated toward the luminal side. Histologic analysis demonstrated robust preservation of elastic fibers and spontaneous differentiation of Muse cells into endothelial cells and vascular smooth muscle cells.
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Cerebral atherosclerosis is a type of atherosclerosis where build-up of plaque in the blood vessels of the brain occurs. Some of the main components of the plaques are connective tissue, extracellular matrix, including collagen, proteoglycans, fibronectin, and elastic fibers; crystalline cholesterol, cholesteryl esters, and phospholipids; cells such as monocyte derived macrophages, T-lymphocytes, and smooth muscle cells. The plaque that builds up can lead to further complications such as stroke, as the plaque disrupts blood flow within the intracranial arterioles. This causes the downstream sections of the brain that would normally be supplied by the blocked artery to suffer from ischemia.
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The 1953 Science article mentioned above concluded that the reticular and regular collagenous materials contains the same four sugars – galactose, glucose, mannose, and fucose – but in a much greater concentration in the reticular than in the collagenous material. In a 1993 paper, the reticular fibers of the capillary sheath and splenic cord were studied and compared in the pig spleen by transmission electron microscopy. This paper attempted to reveal their components and the presence of sialic acid in the amorphous ground substance. Collagen fibrils, elastic fibers, microfibrils, nerve fibers, and smooth muscle cells were observed in the reticular fibers of the splenic cord.
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This adaptation may malfunction: too small a diameter of the resistance vessels relates to insufficient tissue perfusion as well as hypertension. The vascular wall consists of amongst others the vascular smooth muscle cells, endothelial cells that line the lumen, and elastic fibers and other extracellular matrix elements. Physical forces form an important part of the adaptation mechanisms of small arteries: Blood pressure causes distension of the matrix elements, but also induces contraction of the smooth muscle cells and production of more cells and more matrix. Blood flow is sensed by the endothelial cells, which release factors such as nitric oxide that cause relaxation and remodeling towards larger diameters.
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From the internal surface of the fibrous envelope of the corpora cavernosa penis, as well as from the sides of the septum, numerous bands or cords are given off, which cross the interior of these corpora cavernosa in all directions, subdividing them into a number of separate compartments, and giving the entire structure a spongy appearance. These bands and cords are called the trabeculae of corpora cavernosa of penis, and consist of white fibrous tissue, elastic fibers, and plain muscular fibers. In them are contained numerous arteries and nerves. The component fibers which form the trabeculae are larger and stronger around the circumference than at the centers of the corpora cavernosa; they are also thicker behind than in front.
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Estrogens are responsible for the maintenance of collagen, elastic fibers, and vasoculature of the urogenital tract, all of which are important in maintaining vaginal structure and functional integrity; they are also important for maintaining vaginal pH and moisture levels, both of which aid in keeping the tissues lubricated and protected. Prolonged estrogen deficiency leads to atrophy, fibrosis, and reduced blood flow to the urogenital tract, which is what causes menopausal symptoms such as vaginal dryness and pain related to sexual activity and/or intercourse. It has been consistently demonstrated that women with lower sexual functioning have lower estradiol levels. Androgen therapy for hypoactive sexual desire disorder (HSDD) has a small benefit but its safety is not known.
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TGF-β signaling also likely plays a major role in the pathogenesis of Marfan syndrome, a disease characterized by disproportionate height, arachnodactyly, ectopia lentis and heart complications such as mitral valve prolapse and aortic enlargement increasing the likelihood of aortic dissection. While the underlying defect in Marfan syndrome is faulty synthesis of the glycoprotein fibrillin I, normally an important component of elastic fibers, it has been shown that the Marfan syndrome phenotype can be relieved by addition of a TGF-β antagonist in affected mice. This suggests that while the symptoms of Marfan syndrome may seem consistent with a connective tissue disorder, the mechanism is more likely related to reduced sequestration of TGF-β by fibrillin.
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They state that the clitoral glans and labia minora have blood vessels that are dispersed within a fibrous matrix and have only a minimal amount of smooth muscle, or that the clitoral glans is "a midline, densely neural, non-erectile structure". Other descriptions of the glans assert that it is composed of erectile tissue and that erectile tissue is present within the labia minora. The glans may be noted as having glandular vascular spaces that are not as prominent as those in the clitoral body, with the spaces being separated more by smooth muscle than in the body and crura. Adipose tissue is absent in the labia minora, but the organ may be described as being made up of dense connective tissue, erectile tissue and elastic fibers.
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At the cellular level, the aorta and the aortic arch are composed of three layers: The tunica intima, which surrounds the lumen and is composed of simple squamal epithelial cells; the tunica media, composed of smooth cell muscles and elastic fibers; and, the tunica adventitia, composed of loose collagen fibers. Innervated by barometric nerve terminals, the aortic arch is responsible for sensing changes in the dilation of the vascular walls, inducing changes in heart rate to compensate for changes in blood pressure. The aorta begins at the level of the upper border of the second sternocostal articulation of the right side, and runs at first upward, backward, and to the left in front of the trachea; then travels backward on the left side of the trachea and finally passes downward on the left side of the body of the fourth thoracic vertebra. At this point the aortic arch continues as the descending aorta.
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Gerodermia osteodysplastica is characterized by symptoms and features which affect the connective tissues, skin and skeletal system. These are: wrinkly, loose skin over the face, abdomen, and extremities (hands, feet) on the dorsal sides usually worsened by chronic joint laxity and hyperextensibility; fragmented elastic fibers of the skin that are reduced in number, with disorientation of collagen fibers; osteopenia and osteoporosis, with associated fractures; malar hypoplasia (underdeveloped cheek bone), maxillary hypoplasia (underdeveloped upper jaw), mandibular prognathism (protrusion of the lower jaw and chin), bowed long bones, platyspondyly (flattened spine) related to vertebral collapse; kyphoscoliosis (scoliosis with kyphosis, or "hunch back"), metaphyseal peg (an unusual outgrowth of metaphyseal tissue which protrudes into the epiphyseal region of the bone, near the knee); and the overall physical effects and facial appearance of dwarfism with premature aging. Other features and findings include: intrauterine growth retardation, congenital hip dislocations, winged scapulae (shoulder blades), pes planus (fallen arches), pseudoepiphyses of the second metacarpals (upper bone of the fingers), hypotelorism (close-set eyes), malformed ears, developmental delay, failure to thrive and abnormal electroencephalograph (EEG) readings. Dental and orthodontal abnormalities in addition to maxillary hypoplasia and mandibular prognathism have also been observed in gerodermia osteodysplastica.
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