radbio

• Direct Effect


  The effect of radiation if the initial ionizing event occurs on the target molecule
• Free Radicals


  The intermediate molecules
• Radiolysis


  Irradiation of water that results in dissociation into other molecule products
• Stochastic Effect


  Uncontrolled rapid proliferation of cells
• Point Lesion


  The result of disruption of single chemical bonds from radiation interaction with macromolecules
• Deterministic Effect


  If enough cells of the same type respond similarly, then a particular tissue or organ can be destroyed
• Directly


  Linear Dose response is proportionate to the Dose
• in Vitro


  Outside the body or outside the cell
• Main Chain Scission


  Irradiation of macro molecule that results in the breakage of the backbone of the long chain macromolecule
• The occurrence of effect of the initial ionizing radiation on the target molecule is Direct Effect
• OER


  Sensitivity of tissue in relation to aerobic state
• Cross Linking


  The result is the reduction of a long, single molecule into many smaller molecules, each of which may still be macromolecular
• Indirect Effect


  The dissociation into other molecular products secondary to irradiation
• Cell death is an example of Deterministic Effect
• bergonie and tribondeau


  Radio sensitivity
• linear –threshold


  Cancer, leukemia, and genetic effects follows a dose relationship
• Free Radical


  An uncharged molecule that contains a single unpaired electron in the outer shell
• Linear Energy Transfer


  A measure of the rate at which energy is transferred from ionizing radiation to soft tissue
• The radiation response increases in severity with increasing radiation dose is Deterministic Effect
• Relative Biologic Effectiveness


  "As the LET of radiation increases, the ability to produce biologic damage also increases."
• Protraction


  The dose is delivered continuously but at a lower dose rate
• Point Mutation


  Radiation response of dna wherein there is a change or loss of a base, also destroys the triplet code and may not be reversible
• Uncontrolled rapid proliferation of cells that is the principal characteristic of radiation induced malignant disease is Stochastic Effect
• mRna


  Transfers genetic code to build protein
• Main Chain Scission increases the viscosity of a molecular solution
• 200-250 kVp


  Orthovoltage x-radiation
• Fractionation


  The dose is delivered with certain amount of equal fraction separated by certain time
• Hormesis


  The biologic responses to low exposures to toxins or other stressors
• Vitamin K is not a radiosensitizer
• Late


  High Dose response
• Sigmoid


  Skin effect from high dose fluoroscopy follows a dose-response relationship
• Radiation Dose Response


  A mathematical relationship between various radiation dose levels and magnitude of the observed response
• Homeostasis


  The concept of relative constancy of the internal environment of the human body
• Enzymes


  Molecules that are necessary in small quantities to allow a biochemical reaction to continue even though they do not directly enter into the reaction
• Lipids


  Composed of two types glycerol and fatty acids
• Carbohydrates


  Also called as saccharides
• Watson and Crick


  DNA structure description
• The incidence of the radiation response increases with increasing radiation dose is Stochastic Effect
• Hormone


  Molecules that exercise regulatory control over some body functions, such as growth and development
• The ability of ionizing radiation to produce a biologic response increases as the LET of radiation increases