Bones, problems with

C. C. Paterson, H. Shirahata, and J. E. Erickson. Lead in Ancient Human Bones and Its Relevance to Historical Developments of Social Problems with Lead. The Science of the Total Environment. 61 (Mar. 1987) 167-200. 

The most obvious difference between a normal cell and a cancerous one is that control of cell division has been lost in the latter. Since cell division requires synthesis of DNA, the synthesis, structure, and function of DNA have been frequent targets for discovery of antitumor agents. One of the problems with this approach is that some perfectly normal cells in the human body also turn over rapidly, including the cells in the bone marrow that eventually lead to the blood cells and the cells that line the gut. It is not surprising that the dose-limiting toxicity of many cancer drugs is damage to the bone marrow or the gut. 

Metallic biomaterials (metals such as Ti or its alloys and others) are used for the manufacture of orthopaedic implants due to their excellent biocompatibility with respect to electrical and thermal conductivity and their mechanical properties, e.g., for hard tissue replacement such as total hip and knee joints, for fracture healing aids such as bone plates and screws or dental implants. For example, Co-Cr-Mo alloys are employed for metal-on-metal hip bearings in total joint replacements. Problems with implants occur because of ion release in patients with metal implants. To control this ion release, the ultratrace determination of Co, Cr and Mo in the blood (or serum) and urine of patients with Co-Cr-Mo alloy hip implants is carried out routinely in the author s laboratory. The trace metal determination of Co, Cr and Mo in complex matrices such as urine and blood by ICP-MS is not trivial due to the low concentrations expected in the sub-ngmF1 range, the possible danger of contamination during sample collection, sample preparation and the... 

An inherent problem with chemical characterization of bones is that diagenesis may confound the results of the analysis. One possible way to avoid diagenesis and contamination is through the use of a microprobe to sample specific areas of the bone. LA-ICP-MS may prove to be ideally suited for this... 

Gastrointestinal distress (nausea, vomiting, diarrhea) may be a problem with tetracycline use. Hypersensitivity reactions (such as rashes) may also occur, as well as an increase in skin sensitivity to ultraviolet light (photosensitivity).16 Tetracyclines form chemical complexes with calcium that may impair the growth and development of calcified tissues such as bone and teeth, especially in children.69 Tetracyclines also cause discoloration of teeth in children and pregnant women, apparently because of the tetracycline-calcium interaction.69 As mentioned previously, development of tetracycline-resistant strains and resulting superinfections may be a serious problem during tetracycline therapy. 

Oil of Lead is especially effective for diseases affecting the bones, atrophy of the body muscular atrophy, as well as problems with the spleen. It has been used for treating acute lead toxicity, anemia, and neuropathy. It is said to increase steadiness, patience, and tolerance. 

Although the first demonstration that amino acid racemization took place in fossils used mollusc shells (23), the application of this reaction in dating these materials has been extensively investigated only recently (19,20). Work on Mercenaria (19), Chione (20), and other species (24) has tested the application of racemization dating to fossil mollusc shells from geological contexts and Indian shell middens. These and other studies have shown that there are problems with amino acid racemization dating of carbonaceous fossils which are not encountered with bone. Reversible first-order racemization kinetics which are observed in bone... 

Cadmium is chemically similar to the metal zinc, and is absorbed from the gut in a similar way using the same system. It can interfere with zinc in the body and consequently may affect the male reproductive system where zinc is important. Cadmium interferes with the metabolism of calcium too, a critical mineral in the body with which it also has similarities. This interference leads to loss of calcium from the bones which then become brittle (osteomalacia). In the case of itai-itai disease, which was the result of cadmium poisoning in Japan, the exposure to cadmium was accompanied by a deficiency of vitamin D which made the problems with the bones worse. 

One major problem with structural materials is that they crack and weaken as they age. The human body has mechanisms for healing itself if the skin is cut or a bone is broken. However, inanimate materials have had no such mechanisms— until now. Scientists at the University of Illinois at Ur-bana-Champaign (UIUC) have invented a plastic that automatically heals microscopic cracks before they can develop into large cracks that would degrade the usefulness of the material. This accomplishment was achieved by an interdisciplinary team of scientists including aeronautical engineering professors Scott White and Philippe Geubelle, applied mechanics professor Nancy Sottos, and chemistry professor Jeffrey Moore. 

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