Bone growth

Vitamin D3 is a key compound m the process by which Ca " is absorbed from the mtes tine Low levels of vitamin D3 lead to Ca " concentrations m the body that are msuffi cient to support proper bone growth resulting m the bone disease called rickets... 

Bone disease Bone growth factor Bone imaging Bone marrow... 

Vitamins A, D, and E are required by mminants and, therefore, their supplementation is sometimes necessary. Vitamin A [68-26-8] is important in maintaining proper vision, maintenance and growth of squamous epitheHal ceUs, and bone growth (23). Vitamin D [1406-16-2] is most important for maintaining proper calcium absorption from the small intestine. It also aids in mobilizing calcium from bones and in optimizing absorption of phosphoms from the small intestine (23). Supplementation of vitamins A and D at their minimum daily requirement is recommended because feedstuffs are highly variable in their content of these vitamins. 

Other Ceramic Calcium Phosphate Materials. Other ceramic calcium phosphate materials for repairing bony defect iaclude p-tricalcium phosphate (P-TCP) [7758-87-4], P-Ca2(PO, and biphasic calcium phosphate (BCP) ceramics which consist of both P-TCP and HA. Unlike ceramic HA, P-TCP resorbs ia the tissue (293). The in vivo dissolution of BCP ceramic implants was shown (296) to iacrease with increasing P-TCP/HA ratio ia the implants. Both P-TCP and BCP can lead to new bone growth to various extents depending on the appHcations and the type of materials used (293,296). 

Hydroxyapaite, the mineral constituent of bone, is appHed to the surfaces of many dental implants for the purpose of increasing initial bone growth. Some iavestigators beHeve that an added benefit is that the hydroxyapatite shields the bone from the metal. However, titanium and its aHoy, Ti-6A1-4V, are biocompatible and have anchored successfuHy as dental implants without the hydroxyapatite coating. 

Other bone-growth syndromes Schizophrenia (reduced levels in prefrontal cortex) ... 

Du C, Meijer GJ, van de Valk C, Haan Re, Bezemer JM, Hesseling SC, Cui FZ, de Groot K, and Layrolle P. Bone growth in biomimetic apatite coated porous Polyactive 1000PEGT70PBT30 implants. Biomaterials, 2002, 23,4649-4656. 

Bone morphogenetic proteins (BMPs) A family (eight or more) of secreted proteins with a variety of actions on bone many induce ectopic bone growth. 

The U.S. Food and Drug Administration approved several electrical bone growth stimulators, primarily for fractures at the middle of long bones, such as a tibia (shinbone) that has not healed in at least nine months. Also, the mechanisms of healing may not be understood completely manufacturers studies have shown that the device did, in fact, affect cellular processes. 

Studies of other bone-seeking radionuclides provide further support for increased vulnerability during periods of rapid bone growth such as adolescence (Carnes et al. 1997 Lloyd et al. 1999). On the other hand, americium uptake into maternal bone of lactating rats was similar to that of nonlactating rats, while concurrent calcium uptake into bone was lower in lactating rats (Hollins and Durakovic 1972). Thus, active mobilization of bone mineral, per se, may not always promote release of americium from bone (see Section 3.4.2.1). 

Three-parameter expression relates bone formation rate with body and bone growth, according to Bone... 

Studies in rats have shown effects of lead on bone mineralization and bone growth. The effects observed in rats may be relevant to our understanding of the mechanisms for the growth deficits that have been associated with low-level in utero and childhood lead exposures. Additional studies of the effects of lead on bone metabolism in humans and in animal models would improve our understanding of the toxicological significance of lead in bone. 

Hamilton JD, O Flaherty EJ. 1995. Influence of lead on mineralization during bone growth. Fundam Appl Toxicol 26(2) 265-271. 

O Flaherty EJ. 1991b. Physiologically based models for bone-seeking elements. III. Human skeletal and bone growth. Toxicol Appl Pharmacol 111 332-341. 

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