Total bone mineral content

Evaluate total bone mineral content of axial and appendicular skeletal features. 

Bone mineral effect. Coffee, taken by 258 healthy occupationally active men aged 40-63 years, significantly reduced the trabecular bone mineral content. The extent of alcohol intake did not differentiate bone mineral content values at the distal radius, whereas the significant detrimental effects of both smoking and coffee drinking on trabecular (but not cortical and total) bone mineral content were revealed. Simultaneously, smokers and ex-smokers, when... 

In the same study by Lloyd et al. (1996), but after 2 years of CCM supplementation, the Ca group versus the placebo group demonstrated significantly higher BMD (12.2% vs 10.1% p =. 005) and bone mineral content increases (BMC 39.9% vs 35.7% p =. 01) for total body, while bone area remained similar between groups (p =. 15). At the lumbar spine and pelvis, supplemental Ca improved bone accretion compared to placebo by as much as 12-24%. Annualized bone acquisition rate was highest in Ca supplemented subjects with above-median values for... 

Schmid K, Angerer J, Letzel S, et al. 1995. Use of bone mineral content determination by x-ray absorptiometry in the evaluation of osteodystrophy among workers exposed to aluminum powders. Sci Total Environ 163 147-151. 

In ovariectomized rats administered 20 or 40 mg daily of red clover-derived total isoflavones for 14 weeks, treatment with isoflavones significantly increased bone mineral content, mechanical strength of the tibia, femoral weight, and femoral density and prevented the rise of serum alkaline phosphatase levels. In addition, the treatment with isoflavones significantly reduced the number of osteoclasts compared with the ovariectomized control rats (Occhiuto et al. 2007). 

Specker, B. L., Beck, A., Kalkwarf, H., and Ho, M. (1997). Randomized trial of varying mineral intake on total body bone mineral accretion during the first year of life. Available from http //pediatrics.aappublications.Org/cgi/content/abstract/99/6/el2 [Accessed July 2007]. 

Two imaging systems, dual energy X-ray absorptiometry scanning (DEXA) and magnetic resonance imaging (MRI), allow for longitudinal studies of whole body composition. DEXA measures bone mineral density and content, fat content, and lean content in anesthetized mice. Echo MRI from Echo Medical System, Houston, TX, is used to measure whole body composition parameters such as total body fat, lean mass, body fluids, and total body water in live mice without the need for anesthesia or sedation (15). The MRI technology is more rapid, less than a minute to scan one mouse, than DEXA which takes about 5 min per mouse. 

Lead is another element of interest in a number of applications. Most of the ingested lead is stored in bone, and is difficult to remove once it is incorporated into the mineral phase. The half-life of lead in bone can be up to 20 years (Anderson and Danylchuck 1977, Drasch 1982). Lead is not distributed equally among the bones of the skeleton, although there seems to be a relationship among anatomical units within one skeleton that would allow an estimation of total skeletal lead burden (Wittmers et al. 1988). In a modern population of humans (n = 240) that had not been exposed to lead occupationally, the mean lead content in the femur was 3.86 mg/kg bone wet weight as compared to the temporal bone (5.59 mg/kg) and the pelvic bone (1.65 mg/kg) (Drasch et al. 1987). An occupationally exposed population had approximately ten to twenty times the amount of lead in bone compared to the unexposed population (Brito et al. 2000). 

Phosphorus has more known fimctions than any other mineral element in the animal body. The close association of phosphorus with calcium in bone has already been mentioned. In addition, phosphorus occms in phosphoproteins, nucleic acids and phosphohpids.The element plays a vital role in energy metabolism in the formation of sugar-phosphates and adenosine di- and triphosphates (see Chapter 9). The importance of vitamin D in calcimn and phosphorus metabolism has already been discussed in Chapter 5. The phosphorus content of the animal body is considerably less than that of calcimn content. Whereas 99 per cent of the calcium found in the body occurs in the bones and teeth, the proportion of the phosphorus in these structures is about 80-85 per cent of the total the remainder is in the soft tissues and fluids, where it serves the essential fimctions mentioned above. The control of phosphorus metabolism is different from that of calcium. If it is in an available form, phosphorus is absorbed well even when there is an excess over requirement. The excess is excreted via the kidney or the gut (via sahva). In monogastric animals, the kidney is the primary route of excretion. Plasma phosphorus diffuses into saliva and in ruminants the large amount of chewing during rumination results in saliva being the major input of phosphorus into the rumen rather than the food. 

The content of magnesium in the body of an adult is about 25-40 g. This accounts for about 60% of the content of the skeleton. The highest concentrations of magnesium in soft tissues are found in the pancreas, liver and skeletal muscles. Blood and extracellular fluids contain only 1% of the total amount of magnesium in the body. Calcium is quantitatively the major mineral component in the human body. The total amount is about 1500g, with 99% of this being in bones and teeth as calcium phosphate. 

CEdcium is the most abundant mineral present in the body. In an adult man, the total content of calcium is about 1-1.5 kg. It is mostly present in bones and teeth in the form of calcium phosphate and calcium carbonate. The concentration of calcium in bones and teeth is 20 mg lOO gm and its concentration in the serum of blood is 9-11 mg/100 ml. Calcium is also present in the soft tissues of body, extra-cellular fluid and plasma. The richest source of calcium is milk and cheese. It is also present in beans, cabbage, turnip, green vegetables, nuts and egg yolk. Adult human being needs about 800 mg calcimn per day while the growing children and pregnant women may need about 1.5 gram per day. 

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