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Radium (223Ra) Dichloride
Radium-223 (223Ra, Ra-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. Origin and preparation Although radium-223 is naturally formed in trace amounts by the decay of uranium-235, it is generally made artificially,Bruland O.S., Larsen R.H. (2003). Radium revisited. In: Bruland O.S., Flgstad T., editors. Targeted cancer therapies: An odyssey. University Library of Tromso, Ravnetrykk No. 29. , pp. 195–202 by exposing natural radium-226 to neutrons to produce radium-227, which decays with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotopes Of Radium
Radium (88Ra) has no stable or nearly stable isotopes, and thus a standard atomic weight cannot be given. The longest lived, and most common, isotope of radium is 226Ra with a half-life of . 226Ra occurs in the decay chain of 238U (often referred to as the radium series). Radium has 33 known isotopes from 202Ra to 234Ra. In 2013 it was discovered that the nucleus of radium-224 is pear-shaped. This was the first discovery of an asymmetric nucleus. List of isotopes , - , 202Ra , , style="text-align:right" , 88 , style="text-align:right" , 114 , 202.00989(7) , 2.6(21) ms .7(+33−3) ms, , , 0+ , , - , rowspan=2, 203Ra , rowspan=2, , rowspan=2 style="text-align:right" , 88 , rowspan=2 style="text-align:right" , 115 , rowspan=2, 203.00927(9) , rowspan=2, 4(3) ms , α , 199Rn , rowspan=2, (3/2−) , rowspan=2, , - , β+ (rare) , 203Fr , - , rowspan=2 style="text-indent:1em" , 203mRa , rowspan=2, , rowspan=2 colspan="3" style="text-i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radon
Radon is a chemical element with the symbol Rn and atomic number 86. It is a radioactive, colourless, odourless, tasteless noble gas. It occurs naturally in minute quantities as an intermediate step in the normal radioactive decay chains through which thorium and uranium slowly decay into various short-lived radioactive elements and lead. Radon itself is the immediate decay product of radium. Its most stable isotope, 222Rn, has a half-life of only 3.8 days, making it one of the rarest elements. Since thorium and uranium are two of the most common radioactive elements on Earth, while also having three isotopes with half-lives on the order of several billion years, radon will be present on Earth long into the future despite its short half-life. The decay of radon produces many other short-lived nuclides, known as "radon daughters", ending at stable isotopes of lead. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myelotoxicity
Bone marrow suppression also known as myelotoxicity or myelosuppression, is the decrease in production of cells responsible for providing immunity (leukocytes), carrying oxygen (erythrocytes), and/or those responsible for normal blood clotting (thrombocytes). Bone marrow suppression is a serious side effect of chemotherapy and certain drugs affecting the immune system such as azathioprine. The risk is especially high in cytotoxic chemotherapy for leukemia. Nonsteroidal anti-inflammatory drugs (NSAIDs), in some rare instances, may also cause bone marrow suppression. The decrease in blood cell counts does not occur right at the start of chemotherapy because the drugs do not destroy the cells already in the bloodstream (these are not dividing rapidly). Instead, the drugs affect new blood cells that are being made by the bone marrow. When myelosuppression is severe, it is called myeloablation. Many other drugs including common antibiotics may cause bone marrow suppression. Unlike che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone Metastasis
Bone metastasis, or osseous metastatic disease, is a category of cancer metastases that results from primary tumor invasion to bone. Bone-originating primary tumors such as osteosarcoma, chondrosarcoma, and Ewing's sarcoma are rare; the most common bone tumor is a metastasis Bone metastases can be classified as osteolytic, osteoblastic, or both. Unlike hematologic malignancies which originate in the blood and form non-solid tumors, bone metastases generally arise from epithelial tumors and form a solid mass inside the bone. Bone metastases, especially in a state of advanced disease, can cause severe pain, characterized by a dull, constant ache with periodic spikes of incident pain. Types of lesions Under normal conditions, bone undergoes continuous remodeling through osteoclast-mediated bone resorption and osteoblast-mediated bone deposition. These processes are normally tightly regulated within bone to maintain bone structure and calcium homeostasis in the body. Dysregulation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Castration-resistant Prostate Cancer
Prostate cancer is cancer of the prostate. Prostate cancer is the second most common cancerous tumor worldwide and is the fifth leading cause of cancer-related mortality among men. The prostate is a gland in the male reproductive system that surrounds the urethra just below the bladder. It is located in the hypogastric region of the abdomen. To give an idea of where it is located, the bladder is superior to the prostate gland as shown in the image The rectum is posterior in perspective to the prostate gland and the ischial tuberosity of the pelvic bone is inferior. Only those who have male reproductive organs are able to get prostate cancer. Most prostate cancers are slow growing. Cancerous cells may spread to other areas of the body, particularly the bones and lymph nodes. It may initially cause no symptoms. In later stages, symptoms include pain or difficulty urinating, blood in the urine, or pain in the pelvis or back. Benign prostatic hyperplasia may produce similar symptoms. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ossification
Ossification (also called osteogenesis or bone mineralization) in bone remodeling is the process of laying down new bone material by cells named osteoblasts. It is synonymous with bone tissue formation. There are two processes resulting in the formation of normal, healthy bone tissue: Intramembranous ossification is the direct laying down of bone into the primitive connective tissue ( mesenchyme), while endochondral ossification involves cartilage as a precursor. In fracture healing, endochondral osteogenesis is the most commonly occurring process, for example in fractures of long bones treated by plaster of Paris, whereas fractures treated by open reduction and internal fixation with metal plates, screws, pins, rods and nails may heal by intramembranous osteogenesis. Heterotopic ossification is a process resulting in the formation of bone tissue that is often atypical, at an extraskeletal location. Calcification is often confused with ossification. Calcification is sy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strontium-89
Strontium-89 () is a radioactive isotope of strontium produced by nuclear fission, with a half-life of 50.57 days. It undergoes β− decay into yttrium-89. Strontium-89 has an application in medicine. History It was used for the first time by Belgian scientist Charles Pecher. Pecher filed a patent in May 1941 for the synthesis of strontium-89 and yttrium-86 using cyclotrons, and described the therapeutic use of strontium. Physiological effects and medical use Strontium belongs to the same periodic family as calcium (alkaline earth metals), and is metabolised in a similar fashion, preferentially targeting metabolically active regions of the bone. 89Sr is an artificial radioisotope used in the treatment of osseous (bony) metastases of bone cancer. In circumstances where cancer patients have widespread and painful bony metastases, the administration of 89Sr results in the delivery of beta particles directly to the area of bony problem, where calcium turnover is greatest. Con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma Radiation
A gamma ray, also known as gamma radiation (symbol γ or \gamma), is a penetrating form of electromagnetic radiation arising from the radioactive decay of atomic nuclei. It consists of the shortest wavelength electromagnetic waves, typically shorter than those of X-rays. With frequencies above 30 exahertz (), it imparts the highest photon energy. Paul Villard, a French chemist and physicist, discovered gamma radiation in 1900 while studying radiation emitted by radium. In 1903, Ernest Rutherford named this radiation ''gamma rays'' based on their relatively strong penetration of matter; in 1900 he had already named two less penetrating types of decay radiation (discovered by Henri Becquerel) alpha rays and beta rays in ascending order of penetrating power. Gamma rays from radioactive decay are in the energy range from a few kiloelectronvolts (keV) to approximately 8 megaelectronvolts (MeV), corresponding to the typical energy levels in nuclei with reasonably long lifeti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta Particle
A beta particle, also called beta ray or beta radiation (symbol β), is a high-energy, high-speed electron or positron emitted by the radioactive decay of an atomic nucleus during the process of beta decay. There are two forms of beta decay, β− decay and β+ decay, which produce electrons and positrons respectively. Beta particles with an energy of 0.5 MeV have a range of about one metre in air; the distance is dependent on the particle energy. Beta particles are a type of ionizing radiation and for radiation protection purposes are regarded as being more ionising than gamma rays, but less ionising than alpha particles. The higher the ionising effect, the greater the damage to living tissue, but also the lower the penetrating power of the radiation. Beta decay modes β− decay (electron emission) An unstable atomic nucleus with an excess of neutrons may undergo β− decay, where a neutron is converted into a proton, an electron, and an electron antineutrino (the antip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Curie (unit)
The curie (symbol Ci) is a non- SI unit of radioactivity originally defined in 1910. According to a notice in ''Nature'' at the time, it was to be named in honour of Pierre Curie, but was considered at least by some to be in honour of Marie Curie as well, and is in later literature considered to be named for both. It was originally defined as "the quantity or mass of radium emanation in equilibrium with one gram of radium (element)", but is currently defined as 1 Ci = decays per second after more accurate measurements of the activity of 226Ra (which has a specific activity of ). In 1975 the General Conference on Weights and Measures gave the becquerel (Bq), defined as one nuclear decay per second, official status as the SI unit of activity. Therefore: : 1 Ci = = 37 GBq and : 1 Bq ≅ ≅ 27 pCi While its continued use is discouraged by National Institute of Standards and Technology (NIST) and other bodies, the curie is still widely used throughou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Becquerel
The becquerel (; symbol: Bq) is the unit of radioactivity in the International System of Units (SI). One becquerel is defined as the activity of a quantity of radioactive material in which one nucleus decays per second. For applications relating to human health this is a small quantity, and SI multiples of the unit are commonly used. The becquerel is named after Henri Becquerel, who shared a Nobel Prize in Physics with Pierre and Marie Skłodowska Curie in 1903 for their work in discovering radioactivity. Definition 1 Bq = 1 s−1 A special name was introduced for the reciprocal second (s−1) to represent radioactivity to avoid potentially dangerous mistakes with prefixes. For example, 1 µs−1 would mean 106 disintegrations per second: 1·(10−6 s)−1 = 106 s−1, whereas 1 µBq would mean 1 disintegration per 1 million seconds. Other names considered were hertz (Hz), a special name already in use for the reciprocal second, and Fourier ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bayer
Bayer AG (, commonly pronounced ; ) is a German multinational corporation, multinational pharmaceutical and biotechnology company and one of the largest pharmaceutical companies in the world. Headquartered in Leverkusen, Bayer's areas of business include pharmaceuticals; consumer healthcare products, agricultural chemicals, seeds and biotechnology products. The company is a component of the Euro Stoxx 50 stock market index. Bayer was founded in 1863 in Barmen as a partnership between dye salesman Friedrich Bayer and dyer Friedrich Weskott. As was common in this era, the company was established as a dyestuffs producer. The versatility of aniline chemistry led Bayer to expand their business into other areas, and in 1899 Bayer launched the compound acetylsalicylic acid under the trademarked name Aspirin. In 1904 Bayer received a trademark for the "Bayer Cross" logo, which was subsequently stamped onto each aspirin tablet, creating an iconic product that is still sold by Bayer. Ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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