Matrix of connective tissue

Proteoglycans Glycosaminoglycans (mucopolysaccharides) bound to protein chains in covalent complexes. Proteoglycans are present in the extracellular matrix of connective tissue. 

Microscopically, the skin is a multilayered organ composed of many histological layers. It is generally subdivided into three layers the epidermis, the dermis, and the hypodermis [1]. The uppermost nonviable layer of the epidermis, the stratum corneum, has been demonstrated to constitute the principal barrier to percutaneous penetration [2,3]. The excellent barrier properties of the stratum corneum can be ascribed to its unique structure and composition. The viable epidermis is situated beneath the stratum corneum and responsible for the generation of the stratum corneum. The dermis is directly adjacent to the epidermis and composed of a matrix of connective tissue, which renders the skin its elasticity and resistance to deformation. The blood vessels that are present in the dermis provide the skin with nutrients and oxygen [1]. The hypodermis or subcutaneous fat tissue is the lowermost layer of the skin. It supports the dermis and epidermis and provides thermal isolation and mechanical protection of the body. 

Proteoglycan aggregates are typically found in the extracellular matrix of connective tissue. The noncovalent attachment of each proteoglycan to hyaluronic acid via the core protein is mediated by two linker proteins (not shown). Proteoglycans interact with numerous fibrous proteins in the extracellular matrix such as collagen, elastin, and fibronectin (a glycoprotein involved in cell adhesion). 

Fibrillar Collagens Are the Major Fibrous Proteins in the Extracellular Matrix of Connective Tissues... 

Mucopolysaccharides (MPS, also called glycosaminoglycans) are ani nic biopolymers widespread in animal tissues, especially in the intercellular matrix of connective tissues. These polysaccharides arc built up from amino sugars, either D-glucosamine or D-galactosamine, together with uronic acids, either D-glucuronic acid or L-iduronic acid and may have N-acetyl, 0- or N-sulfate groups. 

Apart from this, congenital diseases are known which result from defects in the matrix of connective tissue others, such as cystinuria in which cystine and the basic amino adds are continuously excreted in the urine, seem to be caused by disorders of active transport, presumably as a result of alterations in the carrier proteins. 

The matrix formed in the presence of carbohydrates may be compared with the extracellular matrix of connective tissues. However, the plaque polysaccharides are not glycosaminoglycans but glucans and other high molecular weight homo- and hetero-polysaccharides which are interspersed with the protein component. Examination of the extracellular polysaccharides... 

In biology, extracellular matrix (ECM) is the extracellular part of animal tissue that usually provides structural support to the cells in addition to performing various other important functions. ECM is the defining feature of connective tissue in animals. ECM includes the interstitial matrix and the basement membrane. 

The biological significance of chitosan biomaterials in the hiunan body depends largely on the actions that certain hydrolases exert on them. The resulting chitoohgomers stimulate various cells, while the released monomers are phosphorylated and incorporated into hyaluronan, keratan sulphate and chondroitin sulphate, components of the intracellular matrix and connective tissue [348]. 

T cell activation in the lamina propria is associated with epithelial cell shedding, leading to loss of villi. It has been postulated that this is mediated by increased production of matrix metalloproteases (MMP), which, by degrading the lamina propria matrix, represent a major pathway by which T cells cause injury in the gut (Pender et al., 1997). Production of MMPs also facilitates movement of cells out of the vasculature into sites of inflammation and contributes substantially to the degradation of connective tissue during inflammatory disease (Stetler-Stevenson, 1996). Furthermore, MMPs are required for the release of soluble TNF-a from its membrane... 

Connective Tissue Tissue that supports and binds other tissues. It consists of connective tissue cells embedded in a large amount of extracellular matrix. [NIH]... 

Extracellular matrix, often the major component of connective tissues. 

The family of connective-tissue cells includes fibroblasts, chondrocytes (cartilage cells), and osteoblasts (bone-forming cells). They are specialized to secrete extracellular proteins, particularly collagens, and mineral substances, which they use to build up the extracellular matrix (see p. 346). By contrast, osteoclasts dissolve bone matter again by secreting and collagenases (see p. 342). 

Collagens are quantitatively the most abundant of animal proteins, representing 25% of the total. They form insoluble tensile fibers that occur as structural elements of the extracellular matrix and connective tissue throughout the body. Their name (which literally means glue-producers ) is derived from the gelatins that appear as a decomposition product when collagen is boiled. 

In contrast to milk, where samples are primarily derived from cows, meat analysis has to be performed in samples of a widely different animal origin including cattle, lamb, swine, poultry, and fish. Muscle is a complex matrix with a pH of 5.7, composed of muscle fibers, various types of connective tissue, adipose tissue, cartilage, and bones. Sarcoplasmic proteins such as myoglobin, and glycolytic enzymes are soluble in water while the myofibrillar proteins such as myosin and actin are soluble in concentrated salt solutions (14). The connective tissue proteins, collagen and elastin, are insoluble in both solvents. 

Wu, L.N., Genge, B.R., Sauer, G.R., and R.E. Wuthier, 1996, Characterization and reconstitution of the nucleational complex responsible for mineral formation by growth plate cartilage matrix vesicles. Connect Tissue Res. 35(1 1) 309-15. 

Lamina propria. The structure of the lamina propria is characterized by a hydrated matrix that has a loose structure.96,101 The lamina propria is made up of collagen fibrils, a supporting layer of connective tissue, blood vessels, and smooth muscle.96... 

Aydelotte, M. B. and Kuettner, K. E. (1988) Differences between sub-populations of cultured bovine articular chondrocytes. I. Morphology and cartilage matrix production. Connect. Tissue Res. 18, 205-22. 

The mineralized matrix of bone tissue is strained when loaded. Macro-molecular mechanical connections between the extracellular matrix and the osteocytic cell membrane exist and these connections may be capable of transmitting information from the strained extracellular matrix to the bone cell nuclear membrane. The basis of this mechanism is the physical continuity of the transmembrane integrin molecule, which is connected extracellularly with the macromolecular collagen of the organic matrix and intracellularly with the... 

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