Ground substance

Cascara sagrada is used as a cathartic. It is most useful when prepared as a fluid extract, and tends to be a mild laxative causing Htfle discomfort. However, on prolonged use it may result in characteristic melanotic pigmentation of the rectal mucosa. The bitter taste can be lessened, owing to neutralization of the acid constituents, if the ground substance is moistened and mixed with magnesium or calcium hydroxide. This treatment may lessen the potency of the preparation. 

Grund-sebicht, /. primary layer, fundamental layer ground course, -stein, m. foundation stone, cornerstone lower (mill) stone, -stock, m. matrix, -stoff, m. element raw material base Paper) ground pulp, -stofflndustrie, /. basic industry, -stoff-wechsel, m. basal metabolism, -stricb, m. first coat, priming down stroke, -stuck, m. premises, (real) property. -substanz, /. element basic substance Anat.) ground substance, matrix, -teil, m. element, principle basic part, -teilcben, n. fundamental particle, -ton, m. fundamental tone, primary tone, -umsatz, m. Biol.) basal metabolism. 

Zwischen-mass, n. intermediate size, -masse, /. ground substance interstitial matter. 

Wolosewick, J.J. Porter. K.R. (1979). Microtrabecular lattice of the cytoplasmic ground substance. Artifact or reality. J. Cell Biol. 82, 114-139. 

Mast cells Make ground substance, histamine... 

Fig. 20. hypothetical mode of action of melampolides on skin. C, collagen F, fibroblast GS, ground substance EL, elastine. 

Chloroplasts (29-36) are the sites of photosynthesis and their ribosomes can carry out protein synthesis. Chloroplasts that contain chlorophylls and carotenoids, are disc shaped and 4-6 pm in diameter. These plastids are comprised of a ground substance (stroma) and are traversed by thylakoids (flattened membranous sacs). The thylakoids are stacked as grana. In addition, the chloroplasts of green algae and plants contain starch grains, small lipid oil droplets, and DNA. 

Mitochondria (45-56) are organelles possessing a double membrane, the inner of which is invaginated as cristae. An intermembrane space exists between the inner and outer membranes. The inner membrane consists of an unusually high amount of protein and possesses spherically shaped particles approx 9 nm in diameter. These particles appear to be equivalent to F0, Fb and adenosine triphosphatase. In contrast to the inner membrane, the outer membrane is smooth and appears to be connected to the smooth er. This membrane is permeable to all molecules of 10,000 Dalton or less. A mitochondrial matrix is enclosed by the inner membrane and consists of a ground substance of particles, nucleoids, ribosomes, and electron-transparent regions containing DNA. 

Hyaluronate (hyaluronic acid) Glucuronate (glucuronic acid) (GlcA(Pl-3) GlcNAc (Pl-4)... Ground substance of connective... 

The eukaryotic nuclei once referred to as merely a bag of chromatin has now been recognized to be a highly ordered structure or a hub of cellular activities. The nucleus is seen as a three dimensional mosaic of nucleolus, inter-chromatin regions and condensed chromatin, dispersed in a nuclear ground substance... 

Ih Chemical changes in ground substance and lung protein Rabbit 26... 

Ground substance, which consists of modified sugars, in the form of polymers, and proteins which are associated with the polymers. 

Loose connective tissue An example is subcutaneous, in which the ground substance is gel like and the fibres are irregularly disposed in sheets and bundles. 

Blood and lymph These are the liquid tissues. It is, perhaps, surprising that they are classified as connective tissues, but their structure is the same as that of other connective tissues, except that the ground substance is fluid and the fibres are represented by the proteins such as fibrinogen and the strands of fibrin, which form when blood clots. The cells are the red and white cells (erythrocytes and leucocytes). 

The pleural tissue is a typical connective tissue that consists mostly of matrix the fibrous proteins (collagen, elastin), and mucopolysaccharides, and a few scattered mesothelial cells, capillaries, venules, and ducts. Anatomists have defined several layers (Fig. 3.4) for each of the pleura. Layers 3 and 5 in Fig. 3.4 contain an abundance of fibrous protein, especially elastin. Both the interstitial (Layer 4) and mesothelial (1 and 2) layers contain capillaries of the vascular system and lymphatic channels. The matrix (ground substance) gives the pleura structural integrity and is responsible for its mechanical properties such as elasticity and distensibility. 

The dermis contains several types of cells, including fibroblasts, fat cells, macrophages, histiocytes, mast cells, and cells associated with the blood vessels and nerves of the skin. The predominant cell is the fibroblast, which is associated with biosynthesis of the fibrous proteins and ground substances such as hyaluronic acid, chondroitin sulfates, and mucopolysaccharides. 

Pharmacology Vitamin C, a water-soluble vitamin, is an essential vitamin in man however, its exact biological functions are not fully understood. It is essential for the formation and the maintenance of intercellular ground substance and collagen, for catecholamine biosynthesis, for synthesis of carnitine and steroids, for conversion of folic acid to folinic acid and for tyrosine metabolism. 

Vitamin C (ascorbic acid) is essential for the maintenance of the ground substance that binds cells together and for the formation and maintenance of collagen. The exact biochemical role it plays in these functions is not known, but it may be related to its ability to act as an oxidation-reduction system. 

Cytoplasm The ground substance of the cell In which are situated the nucleus, endoplasmic reticulum, mitochondria and other organelles. 

By constricting the vascular bed, such coadministered vasoactive excipients as epinephrine can reduce the rate of uptake from the SC sites (4a). By contrast, the excipient hyaluronidase breaks down the interstitial barrier by lysing hyaluronic acid, a polysaccharide that helps form the intercellular ground substance of connective tissue (4b). This in effect spreads the injected drug solution over a larger area of connective tissue, increasing the absorption surface, and thereby increasing both the volume that can normally be injected SC (Table 1) and the rate of uptake (6). 

Biochemically lead binds to sulfhydryl (-SH) groups in proteins, that is, it can inhibit enzymes and affect the structures and functions of structural proteins. Some of the effects of this binding include increased permeability of the blood-brain-barrier, breakdown of vascular tissue, destruction of the ground substance in cells leading to conditions of anemia and kidney damage. 

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