Biomaterial Database

Influence of hyperthermia on the oxygen enhancement ratio for x-rays, measured in vivo. 1979

C C Morris, and S B Field

The skin of mouse tail has been used to study the effect of hyperthermia on the oxygen enhancement ratio (OER). Heating was by immersion of a portion of the tail in hot water. Radiation was given either immediately before or after hyperthermia. The average skin reaction between 15 and 50 days after treatment was taken as the end-point. The OER in the absence of hyperthermia was 1.77, suggesting significant hypoxia of the skin. When hyperthermia was given after irradiation the measured value for the OER was not significantly different, but with prior hyperthermia the OER was increased to an average value of 2.3. This increase in OER is probably due to a transient increase in blood circulation following hyperthermia and causing improved tissue oxygenation during irradiation. As a consequence we would expect a greater thermal enhancement ratio for heat given before irradiation than afterwards, and this has frequently been observed with other normal tissues. There was no evidence that heat reduces OER, as has been reported by some authors on the basis of experiments performed on cells in vitro.

UI	MeSH Term	Description	Entries
D010100	Oxygen	An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.	Dioxygen,Oxygen-16,Oxygen 16
D011833	Radiation Injuries, Experimental	Experimentally produced harmful effects of ionizing or non-ionizing RADIATION in CHORDATA animals.	Experimental Radiation Injuries,Injuries, Experimental Radiation,Experimental Radiation Injury,Radiation Injury, Experimental
D001831	Body Temperature	The measure of the level of heat of a human or animal.	Organ Temperature,Body Temperatures,Organ Temperatures,Temperature, Body,Temperature, Organ,Temperatures, Body,Temperatures, Organ
D004307	Dose-Response Relationship, Radiation	The relationship between the dose of administered radiation and the response of the organism or tissue to the radiation.	Dose Response Relationship, Radiation,Dose-Response Relationships, Radiation,Radiation Dose-Response Relationship,Radiation Dose-Response Relationships,Relationship, Radiation Dose-Response,Relationships, Radiation Dose-Response
D005260	Female		Females
D006358	Hot Temperature	Presence of warmth or heat or a temperature notably higher than an accustomed norm.	Heat,Hot Temperatures,Temperature, Hot,Temperatures, Hot
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012867	Skin	The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.
D014965	X-Rays	Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard X-rays are the higher energy, shorter wavelength X-rays. Soft x-rays or Grenz rays are less energetic and longer in wavelength. The short wavelength end of the X-ray spectrum overlaps the GAMMA RAYS wavelength range. The distinction between gamma rays and X-rays is based on their radiation source.	Grenz Ray,Grenz Rays,Roentgen Ray,Roentgen Rays,X Ray,X-Ray,Xray,Radiation, X,X-Radiation,Xrays,Ray, Grenz,Ray, Roentgen,Ray, X,Rays, Grenz,Rays, Roentgen,Rays, X,X Radiation,X Rays,X-Radiations
D051379	Mice	The common name for the genus Mus.	Mice, House,Mus,Mus musculus,Mice, Laboratory,Mouse,Mouse, House,Mouse, Laboratory,Mouse, Swiss,Mus domesticus,Mus musculus domesticus,Swiss Mice,House Mice,House Mouse,Laboratory Mice,Laboratory Mouse,Mice, Swiss,Swiss Mouse,domesticus, Mus musculus