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The extent of how radiation effects cells depends on the type of cell and the dosage of the radiation. Some irradiated cancer cells have been shown to exhibit DNA methylation patterns due to epigenetic mechanisms in the cell. In medicine, medical diagnostic methods such as CT scans and radiation therapy expose the individual to ionizing ...
Damage to hair cells can cause damage to the vestibular system and therefore cause difficulties in balancing. However, other vertebrates, such as the frequently studied zebrafish, and birds have hair cells that can regenerate. [5] [6] The human cochlea contains on the order of 3,500 inner hair cells and 12,000 outer hair cells at birth. [7]
[29] [30] [28] Although both H1 and H2 are present in the mammalian cell nucleus, H2 is the dominant source of RNase H activity there and is important for maintaining genome stability. [ 28 ] Some prokaryotes possess an additional H2-type gene designated RNase HIII in the Roman-numeral nomenclature used for the prokaryotic genes.
The best known explanation of the oxygen effect is the oxygen fixation hypothesis developed by Alexander in 1962, [9] which posited that radiation-induced non-restorable or "fixed" nuclear DNA lesions are lethal to cells in the presence of diatomic oxygen. [10] [11] Recent hypotheses include one based on oxygen-enhanced damage from first ...
The destructive action of hydroxyl radicals has been implicated in several neurological autoimmune diseases such as HIV-associated dementia, when immune cells become over-activated and toxic to neighboring healthy cells. [4] The hydroxyl radical can damage virtually all types of macromolecules: carbohydrates, nucleic acids , lipids (lipid ...
Hair is a stratified squamous keratinized epithelium made of multi-layered flat cells whose rope-like filaments provide structure and strength to the hair shaft. The protein called keratin makes up hair and stimulates hair growth. Hair follows a specific growth cycle with three distinct and concurrent phases: anagen, catagen, and telogen. Each ...
The human body contains many types of cells and a human can be killed by the loss of a single tissue in a vital organ [citation needed]. For many short term radiation deaths (3 days to 30 days) the loss of cells forming blood cells (bone marrow) and the cells in the digestive system (wall of the intestines) cause death.
The radiation-induced bystander effect (bystander effect) is the phenomenon in which unirradiated cells exhibit irradiated effects as a result of signals received from nearby irradiated cells. In November 1992, Hatsumi Nagasawa and John B. Little first reported this radiobiological phenomenon.