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M O Mattsson

Publications and source records attributed to M O Mattsson.

20 records · Page 2Linked to original sources

Cyclic AMP and cell differentiation in amphibian embryonic explants.

Conflicting results have been published concerning the effects of cyclic nucleotides on amphibian cell differentiation. Here we report the effects of cyclic adenosine monophosphate (cAMP) and dibutyryl-cyclic adenosine monophosphate (db-cAMP) on isolated explants from late blastulae of Ambystoma mexicanum and Xenopus laevis. Both cAMP and db-cAMP (10(-4)-10(-9) M) promote 'neuralizing' differentiation in Ambystoma explants. Xenopus explants treated with the nucleotides (10(-4), 10(-6), 10(-8) M) LiCl or heparan sulphate only give rise to ciliated aggregates or dissociation. The results confirm observations that different amphibian species react in different ways to activating chemicals.

Ambystoma↗

DNA damage, cell kinetics and ODC activities studied in CBA mice exposed to electromagnetic fields generated by transmission lines.

CBA mice were exposed outdoors to 50 Hz electromagnetic fields (EMF), with a flux density of about 8 microT rms (root mean square), generated by a 220 kV transmission line. Assays were performed in order to investigate, the possible genotoxic effects after 11, 20 and 32 days of exposure, as well as the effects on body weight, leukocytes, erythrocytes, and the level of ornithine decarboxylase (ODC) activity in spleen and testis. DNA migration was studied on brain cells by single cell electrophoresis (comet assay). After 32 days of exposure a highly significant change of the tail/head ratio of the comets was observed (p < 0.001), showing DNA-damage. Further, a decreased number of mononuclear leukocytes (0.02 < p < 0.05) was observed in mice EMF-exposed for 20 days. In summary, our data indicate that transmission lines of this type may induce genotoxic effects in mice, seen as changes in the DNA migration. These results might have an important implication for health effects.

Animals↗