THE BIOLOGICAL EFFECTS OF HIGH DOSAGE X-RADIATION UPON DIVIDING, NON-DIVIDING CELLS AND OTHER STAGES OF PARAMECIUM USING THE NEWLY DEVELOPED NYLON RADIATION CHAMBER METHOD
Abstract
In connection with a study of the biological effects of x-radiation upon various mitotic stages of paramecia, a new type of radiation chamber was developed. The new device consists of a piece of 1-in. machined Plexiglas with 2 ice wells and holes for 4 nylon hypodermic syringes of 2-cc capacity (0.1-cc graduation). A machined Lucite cap is tightly fitted over the tapering end of each syringe. Clones of 7 species of paramecia were irradiated in increment dosages of 50,000 r up to 600,000 r; specimens were cultivated ins dessicated lettuce medium with Aerobacter aerogenes. Each experiment involved 800 specimens (200/syringe in 2 cc of fluid); after each dosage, 10 cells were expressed from the syringes and observed periodically for 48 hr. The species exhibited x-ray sensitivity in the following order: P. bursaria, P. caudatum, P. aurelia, P. polycaryum, and P. trichium (LD50:170,000 r). Variations from the percent- survival curves indicated sensitivity levels and specimen differences. Nontoxic hematoporphyrin (1:10,000 to 1:40,000) placed in the syringes with normal paramecia caused 100% mortality in 12 hr after irradiation with 100,000 r; as with paramecia, cancer cells in the presence of porphyrin appeared to be weakened in their resistance against x-rays. Sodium pentobarbital, sodium nitrite, and cysteine hydrochloride did not protect paramecia from radiation lethality. When lethality was reached, P. polycaryum disintegrated rapidly. P. caudatum, with dosages of 200,000 r to 250,000 r, moved slower with reduction in contractile vacuole formation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1953
- Accession Number
- AD0022226
Entities
People
- Ralph Wichterman
Organizations
- Temple University