Bone decalcification

On the other hand, excessive secretion of HGH in the growing years leads to gigantism. HGH is also used in cases of muscular dystrophy, bone decalcification (osteoporosis), and hemorrhagic gastric ulcers. 

Secondly, Cd directly interferes with the gastrointestinal calcium absorption leading to the bone decalcification found in osteoporosis. 

Paradoxically, although chronic exposure to high PTH levels leads to bone decalcification, administration in pulses, as a once-a-day injection,... 

If the rate of uptake of retinol from the intestine consistently exceeds the capacity of the liver to dispose of it, significant amounts of retinol, mainly in the form of retinyl palmitate, appear in the general circulation and may give rise to toxic effects. The effects of hypervitaminosis A are many and varied. They include increased intracranial pressure, severe headache, hyperirritability, vomiting, diarrhoea, bone decalcification and skin lesions. The condition can be fatal. It has in the past been caused by over-zealous administration of concentrated sources of the vitamin such as halibut liver oil. This may contain several hundred times as much vitamin A and 40 times as much vitamin D as cod liver oil. It has also occurred in people who have eaten polar bear or husky dog liver which contain massive amounts of vitamin A. 

The Japanese disease itai-itai (ouch-ouch) is a particular syndrome caused by chronic cadmium poisoning. It leads to fractures of long bones due to decalcification, and to muscular dystrophy. The first time the disease was... 

HF solutions in contact with skin result in marked tissue destruction undissociated FIF readily penetrates skin and deep tissue, where the corrosive fluoride ion can cause necrosis of soft tissues and decalcification of bone the destruction produced is excruciatingly painful.Fluoride ion also attacks enzymes (e.g., of glycolysis) and cell membranes. The process of tissue destruction and neutralization of the hydrofluoric acid is prolonged for days, unlike other acids, which are rapidly neutral-ized. ° Because of the insidious manner of penetration, a relatively mild or minor exposure can cause a serious burn. When skin contact is with solutions of less than 20%, the burn manifests itself by pain and erythema with a... 

Callis, G., and Sterchi, D. 1998. Decalcification of bone Literature review and practical study of various decalcifying agents, methods, and their effects of bone histology. J. Histotechnol. 27 49-58. 

Paws can be stored in 70% ethanol for years until further processing. For further processing, paws need to be decalcified (see below) before they are embedded in paraffin. Before decalcification, X-rays of the hind paws can be made for radiologic analysis in which demineralization and erosions of bone are scored. For further details see ref. (6). 

Decalcification will take 4-6 weeks. Decalcification can be monitored with use of X-rays to check whether the bone has demineralized. 

Over time, bone is broken down by physical breaking, decalcification, and dissolution due to the factors mentioned previously. Upon exhumation of a body, bones may appear to retain their general shape and form however, in many instances the bones will readily crumble when touched, and the skeletal remains will disintegrate. Conversely, under suitable conditions, the bones may become fossilized and be preserved for millions of years (Micozzi 1991). 

Related phenomena have been discovered. For example, osteoporosis can be cured by the application of a direct current, the bone being the cathode. It seems that it is Cu2+ and its diffusion out from the bone that causes the osteoporosis, so that decalcification, which is often the term used to describe osteoporosis, is a misnomer (Becker, 1991). 

Rosbash, D.O. and Leavitt, D., Decalcification of bone with trifluoroacetic acid, Am. J. Clin. Pathol. 22, 914-915, 1952 Katz, J.J., Anhydrous trifluoroacetic acid as a solvent for proteins, Nature 174, 509, 1954 Uphaus, R.A., Grossweiner, L.I., Katz, J.J., and Kopple, K.D., Fluorescence of tryptophan derivatives in trifluoroacetic acid, Science 129, 641-643, 1959 Acharya, A.S., di Donato, A., Manjula, B.N. et al., Influence of trifluoroacetic acid on retention times of histidine-containing tryptic... 

DEFICIENCY Deficiency causes hypocalcemia and hypophosphatemia, with resultant rickets (bending with poor calcification of developing bone in riuldren) or osteomalacia (decalcification and sofietring of bones in adults). In both of these there is impaired mineralization. These should be distinguished from another condition, osteoporosis, in which there is reductioii in bone mass as a whole, rather than select reduction of the mineral content. 

In osteomalacia, the bone matrix is quantitatively and qualitatively normal, while the bones show a reduced content of minerals. There is ostalgia and muscle weakness as well as arcuation of the long tubular bones. X-ray imaging shows band-shaped zones of decalcification, usually in symmetrical arrangement, particularly at the ribs, femoral neck and pelvis (so-called Looser-Milkman s syndrome). 

Osteomalacia, a very rare manifest form of hepatic osteopathy, causes pain mainly in the muscles, but less so in the bones. Biochemically, AP is markedly increased there is a deficiency of calcium, phosphate and 25-hydroxycholecalciferol. Radiologic diagnosis shows signs of Looser-Milkman s syndrome coarsening of cancellous bone structure, narrowing of the compacta in the tubular bones, reduced density of the skeletal system, and band-shaped zones of decalcification. 

Secondary hyperparathyroidism arises from chronic hypocalcemia. This condition can result from renal failure leading to poor reabsorption of calcium from the urinary filtrate. It can also arise from poor nutrition or malabsorption of vitamin D by the intestine. In response, parathyroid glands increase their secretion of PTH. This condition also leads to decalcification of bone. Tertiary hyperparathyroidism is often seen after renal transplantation. In these patients, the parathyroid gland secretes the hormone independently of blood calcium levels. 

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