[Possible inducible nature of radioresistant DNA synthesis stimulated by 5-fluorodeoxyuridine]. / O vozmozhnoi indutsibel'noi prirode radiorezistentnogo sinteza DNK, stimulirovannogo v kletkakh deistviem 5-ftordezoksiuridina.

A study was made of the effect of cycloheximide on the radioresistant DNA synthesis stimulated by preincubation of cells with 5-fluorodeoxyuridine (FdUrd). It was shown that after the cycloheximide treatment the radioresistant DNA synthesis was absent while in FdUrd-treated cells it did occur. It is assumed that the FdUrd-stimulated radioresistant DNA synthesis is of an inducible nature.

[5-fluorodeoxyuridine induces radioresistant synthesis of DNA and sensitizes HeLa cells to gamma radiation]. / 5-ftordezoksiuridin indutsiruet radiorezistentnyi sintez DNK i sensibiliziruet kletki HeLa k gamma-oblucheniiu.

It was shown that preincubation of HeLa cells with 5-fluorodeoxyuridine (10(-6) M) induced DNA synthesis resistant to gamma-radiation (6 Gy). At the same time, the death rate of exposed cells increased and nucleoid relaxation decreased. The role of DNA synthesis inhibitors in the reproductive death of exposed cells is discussed.

Serum enzyme activity in bone tumors and osteomyelitis (LDH, GOT, GPT, CPK, CHE, ALP, AP, PP, ALD).

Enzyme activity of lactate dehydrogenase, glutamate-oxalacetate and glutamate-pyruvate transaminase, creatine phosphokinase, cholinesterase, alkaline, acid and prostatic phosphatase and aldolase has been studied in a total of 213 subjects, of whom 97 were of good health, 63 had bone tumors and 53 suffered from osteomyelitis. The activities of the majority of the enzymes were found to become significantly changed in comparison with the norm. In both patient groups, the more striking differences being noted in that of osteomyelitis. However, enzymatic activity alone does not allow to differentiate the group of bone tumors from that of osteomyelitis, the differences between these two groups not being of significance in any one of the enzymes followed.