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Biomedical subjects

R Finollo

Publications and source records attributed to R Finollo.

25 records · Page 2Linked to original sources
PubMed1981

[Viscosimetric evaluation of DNA fragmentation induced in vivo by alkylating agents].

A sensitive viscosimetric approach for measuring DNA single-strand breaks induced by low doses of alkylating agents is presented. The assay is based on the breaks-induced increasing rate of strand separation of rat liver DNA in alkaline solution (pH 12,5; 22 C). Because of the strong dependence of viscosity on DNA unwinding, measurement of time-course of viscosity increase can be used to detect small breakage of DNA. The kinetics of DNA denaturation has been also studied under two different alkaline conditions.

Alkylating Agents↗
PubMed1979

DNA damage and repair induced by diazoacetyl derivatives of amino acids with different mechanism of cytotoxicity. Correlations with mutagenicity and carcinogenicity.

Eight synthetic N-diazoacetyl amino acids, prepared by inserting a diazoacetyl group onto the alpha-nitrogen of a natural amino acid, and two natural diazoazetyl amino acids, azaserine (9-diazoacetyl-L-serine) and DON (6-diazo-5-oxo-L-norleucine), have been studied by autoradiography for their capacity to induce DNA repair synthesis in mouse cells cultivated "in vitro". Dose-dependent unscheduled DNA synthesis was present in cells treated with the eight N-diazoacetyl derivatives, and was absent in cells exposed to approximately equitoxic concentrations of azaserine and DON. Azaserine and DON, unlike N-diazoacetyl derivatives, did not alkylate gamma-(4-nitrobenzyl) pyridine at an appreciable extent. When DNA damage (single stranded breaks or weak points in alkali) was measured by the sensitive technique of alkaline elution, DGA was found about 4 times as potent as azaserine and about 12 times as DON on a molar basis, but about 800 and 17,000 times as potent as azaserine and DON respectively by extrapolating to equitoxic concentrations. Carcinogenicity and mutagenicity seem to follow mainly the capability of inducing DNA damage.

Alkylation↗
PubMed1978

DNA repair synthesis in primary cultures of kidneys from BALB/c and C3H mice treated with dimethylnitrosamine.

A combined 'in vivo--in vitro' autoradiographic method was employed to examine the DNA repair induced in the kidney by a single dose of dimethylnitrosamine (DMNA). Unscheduled DNA synthesis was found to be dose-dependent in primary kidney cultures of DMNA-treated mice, and practically not detectable in controls. Its amount was positively correlated with the different susceptibility of C3H and BALB/c mice to kidney tumor induction by DMNA. This experimental model appears sensitive and able to provide repeatable results. It may be useful to detect the organotropic activity of a carcinogen toward the kidney.

Animals↗
PubMedDate not supplied

[An effective immunodepressive treatment for demonstrating in allogeneic mice the tumorigenic properties of cells grown in vitro (author's transl)].

Short intensive treatment with N-diazoacetylglycine amide (DGA) before the inoculum, followed by prolonged daily administration of L-asparaginase (Asnase), was tested for its ability to elicit tumorigenic properties of fibroblast-like cells cultured in vitro. With this treatment progressive tumor growth was obtained in allogeneic mice injected with cells of a transformed subline. Results show that combined use of DGA and Asnase affords a higher probability of proving in vivo the tumorigenic properties of injected cells than in newborm or X-irradiated recipients. Experimental data indicate that L-asparagine depletion does not inhibit the in vitro growth of fibroblast-like cells.

Animals↗