Bone seeker

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A bone seeker is an element, often a radioisotope, that tends to accumulate in the bones of humans and other animals when it is introduced into the body.

For example, strontium and radium are chemically similar to calcium and can replace the calcium in bones. [1] [2] Plutonium is also a bone seeker, though the mechanism by which it accumulates in bone tissue is unknown. [3]

Radioactive bone seekers are particular health risks as they irradiate surrounding tissue, though this can be useful for radiotherapy   radium-223 is used in this way. [2] [4] Stable bone seekers can also be harmful: excessive strontium absorption has been linked with increased levels of rickets. [5] [6] The salt strontium ranelate, however, is a bone seeker which is sometimes used to strengthen bones as a treatment for osteoporosis. [7] Bone seekers have been proposed as a method of delivering antibiotics to infected bone tissue. [8]

See also

Related Research Articles

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<span class="mw-page-title-main">Osteomalacia</span> Softening of bones due to impaired bone metabolism

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<span class="mw-page-title-main">Osteopenia</span> Abnormally low bone mineral density

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<span class="mw-page-title-main">X-linked hypophosphatemia</span> X-linked dominant disorder that causes rickets

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<span class="mw-page-title-main">Strontium ranelate</span> Chemical compound

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Medication-related osteonecrosis of the jaw is progressive death of the jawbone in a person exposed to a medication known to increase the risk of disease, in the absence of a previous radiation treatment. It may lead to surgical complication in the form of impaired wound healing following oral and maxillofacial surgery, periodontal surgery, or endodontic therapy.

<span class="mw-page-title-main">Vitamin D deficiency</span> Human disorder

Vitamin D deficiency or hypovitaminosis D is a vitamin D level that is below normal. It most commonly occurs in people when they have inadequate exposure to sunlight, particularly sunlight with adequate ultraviolet B rays (UVB). Vitamin D deficiency can also be caused by inadequate nutritional intake of vitamin D; disorders that limit vitamin D absorption; and disorders that impair the conversion of vitamin D to active metabolites, including certain liver, kidney, and hereditary disorders. Deficiency impairs bone mineralization, leading to bone-softening diseases, such as rickets in children. It can also worsen osteomalacia and osteoporosis in adults, increasing the risk of bone fractures. Muscle weakness is also a common symptom of vitamin D deficiency, further increasing the risk of fall and bone fractures in adults. Vitamin D deficiency is associated with the development of schizophrenia.

Radium-223 is an isotope of radium with an 11.4-day half-life. It was discovered in 1905 by T. Godlewski, a Polish chemist from Kraków, and was historically known as actinium X (AcX). Radium-223 dichloride is an alpha particle-emitting radiotherapy drug that mimics calcium and forms complexes with hydroxyapatite at areas of increased bone turnover. The principal use of radium-223, as a radiopharmaceutical to treat metastatic cancers in bone, takes advantage of its chemical similarity to calcium, and the short range of the alpha radiation it emits.

<span class="mw-page-title-main">Alfacalcidol</span> Chemical compound

Alfacalcidol is an analogue of vitamin D used for supplementation in humans and as a poultry feed additive.

<span class="mw-page-title-main">Vitamin D</span> Group of fat-soluble secosteroids

Vitamin D is a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, along with numerous other biological functions. In humans, the most significant compounds within this group are vitamin D3 (cholecalciferol) and vitamin D2 (ergocalciferol).

<span class="mw-page-title-main">Osteoradionecrosis</span> Osteoradionecrosis is an Acute form of Osteomyelitis

Osteoradionecrosis (ORN) is a serious complication of radiation therapy in cancer treatment where radiated bone becomes necrotic and exposed. ORN occurs most commonly in the mouth during the treatment of head and neck cancer, and can arise over 5 years after radiation. Common signs and symptoms include pain, difficulty chewing, trismus, mouth-to-skin fistulas and non-healing ulcers.

Targeted alpha-particle therapy is an in-development method of targeted radionuclide therapy of various cancers. It employs radioactive substances which undergo alpha decay to treat diseased tissue at close proximity. It has the potential to provide highly targeted treatment, especially to microscopic tumour cells. Targets include leukemias, lymphomas, gliomas, melanoma, and peritoneal carcinomatosis. As in diagnostic nuclear medicine, appropriate radionuclides can be chemically bound to a targeting biomolecule which carries the combined radiopharmaceutical to a specific treatment point.

<span class="mw-page-title-main">Charles Pecher</span>

Charles Pecher was a Belgian pioneer in nuclear medicine. He discovered and introduced strontium-89 in medical therapeutic procedures in 1939.

References

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  2. 1 2 Suominen, Mari I.; Wilson, Timothy; Käkönen, Sanna-Maria; Scholz, Arne (10 August 2019). "The Mode-of-Action of Targeted Alpha Therapy Radium-223 as an Enabler for Novel Combinations to Treat Patients with Bone Metastasis". International Journal of Molecular Sciences. 20 (16): 3899. doi: 10.3390/ijms20163899 . PMC   6720648 . PMID   31405099.
  3. Vidaud, Claude; Miccoli, Laurent; Brulfert, Florian; Aupiais, Jean (26 November 2019). "Fetuin exhibits a strong affinity for plutonium and may facilitate its accumulation in the skeleton". Scientific Reports. 9 (1): 17584. Bibcode:2019NatSR...917584V. doi:10.1038/s41598-019-53770-6. PMC   6879641 . PMID   31772265.
  4. Marques, I.A.; Neves, A.R.; Abrantes, A.M.; Pires, A.S.; Tavares-da-Silva, E.; Figueiredo, A.; Botelho, M.F. (July 2018). "Targeted alpha therapy using Radium-223: From physics to biological effects". Cancer Treatment Reviews. 68: 47–54. doi:10.1016/j.ctrv.2018.05.011. PMID   29859504.
  5. Ozgur, S; Sumer, H; Kocoglu, G (1 December 1996). "Rickets and soil strontium". Archives of Disease in Childhood. 75 (6): 524–526. doi:10.1136/adc.75.6.524. PMC   1511822 . PMID   9014608.
  6. RELEVANCE TO PUBLIC HEALTH. Agency for Toxic Substances and Disease Registry (US). April 2004. Retrieved 8 April 2024.
  7. Blake, Glen M; Fogelman, Ignac (December 2006). "Strontium ranelate: a novel treatment for postmenopausal osteoporosis: a review of safety and efficacy". Clinical Interventions in Aging. 1 (4): 367–375. doi: 10.2147/ciia.2006.1.4.367 . PMC   2699648 . PMID   18046914.
  8. Rotman, Stijn G.; Thompson, Keith; Grijpma, Dirk W.; Richards, Robert G.; Moriarty, Thomas F.; Eglin, David; Guillaume, Olivier (March 2020). "Development of bone seeker–functionalised microspheres as a targeted local antibiotic delivery system for bone infections". Journal of Orthopaedic Translation. 21: 136–145. doi:10.1016/j.jot.2019.07.006. PMC   7152806 . PMID   32309139.