Radiomimetics

Radiomimetics are a class of agents that cause DNA damage of a similar quality to that resulting from exposure to ionizing radiation. 

This material is hazardous through inhalation, skin absorption, penetration through broken skin, ingestion, and produces local skin/eye impacts. Trichothecenes are radiomimetic and may cause bone marrow suppression, liver failure, and internal bleeding. 

There is evidence that ozone is a radiomimetic gas. Ozone affects pollen germination in some spedes and thus may directly affect yield. 

DNA s5mthesis and also interfere with cell replication. Alkylating agents has got cytotoxic action and damage the nuclei of growing and multiplying cells. They have got immunosuppressant action also and suppress antibody production. They also have radiomimetic (like ionizing radiation) actions. 

It acts by cross-linking of DNA. It also has radiomimetic property. It is bound to plasma proteins and is excreted slowly unchanged in urine. It is effective in metastatic testicular and ovarian carcinoma, advanced bladder carcinoma and refractory squamous cell head and neck carcinoma. 

Heslot, H. (1962) A quantitative study of biochemical reversions induced in the yeast Schizosaccharomyces pombe by radiations and radiomimetic substances. Abh. Dtsch. Akad. IViss. Berlin Kl. Med., 1, 19,3-228... 

Thacker, J. (1976) Radiomimetic effects of hydrogen peroxide in the inactivation and mutation of yeast. Radiat. Res., 68, 371-380... 

The reactions of peroxyl radicals derived from polyhydric alcohols were studied by using flash photolysis of H202 as the radiomimetic system,116 and by various product studies on ethylene glycol,148,149 glycerol,149 erythritol,145 D-arabinitol,149 D-mannitol,148,149 D-glu-citol,145,150,151 myo-inositol,147,152-154 and scyMo-inositol.77... 

The radiation chemistry of neutral sugars in aqueous solution follows lines similar to those reported for the polyhydric alcohols (see Sect. 111,1) however, the lactol bridge introduces a new and interesting feature. E.s.r.-spectroscopic studies have been made on frozen solutions155-159 and on radiomimetic systems.48,131,160,161 Except for the small aldehydes glycolaldehyde and glyceraldehyde,48 the complexity... 

In yeast and in Ustilago, ionizing radiation, UV and radiomimetic chemicals all induce recombination in mitotic cells (Holliday, 1961 Roman and Jacob, 1957). It is likely that the same is true of mammalian cells, since Wolff et al. (1975)... 

Yet this type of damage is not restricted to ionizing radiation, but certain radiomimetic drugs such as BLM and NCS can similarly produce two (or more) damaged sites in close proximity (Steighner and Povirk 1990 Meschwitz et al. 1992). 

Hicks SP (1954) The effects of ionizing radiation, certain hormones, and radiomimetic drugs on the developing nervous system. J Cell Physiol, 43(Suppl 1) 151-178. 

International symposium, Genetic Effects of Radiation and Radiomimetic Chemicals ... 

Cradiom, A.R. and J.J. Roberts. 1965. Reactions of cultured mammalian cells of varying radiosensitivity widi die radiomimetic alkylating agent mustard gas.. Prog. Biochem. Pharmacol. 1 320-326. 

Trichothecenes cause apoptosis and/or necrosis in the lymphoid, hematopoietic, and gastrointestinal systems resulting in leukopenia, vomiting, and diarrhea that can be lethal. In addition, trichothecenes are toxic to the skin and testes. Immune suppression and increased susceptibihty to infection may occur, especially in the late phase of the disease. The toxic effects from trichothecenes largely resemble those following radiation exposure (radiomimetic) due to effects on rapidly dividing cells in the intestine, bone marrow, and testis. 

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