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R J Kissane

Publications and source records attributed to R J Kissane.

4 recordsLinked to original sources
PubMed1979

Cadmium-induced alterations in RNA metabolism in cultures of Chinese hamster cells sensitive to and resistant to the cytotoxic effects of cadmium.

A variant population (CdR) of cultured Chinese hamster cells (line CHO) was derived that is more than 100 times as resistant to the cytotoxic effects of Cd2+ than is the parent population. The effects on RNA metabolism of exposure to sublethal concentrations of Cd2+ were studied in CHO and CdR. Exposure to 2 X 10(-7) M CdCl2 for 24 h resulted in increased polysome content (1.2 times) and increased uridine or adenosine incorporation into heterogeneous nuclear RNA (1.2-1.4 times) and messenger RNA ((1.5-1.7 times) in both populations. Measurement of ATP pool specific activity following exposure to radiolabeled adenosine showed that increased incorporation reflects increased synthesis. The equivalence of CHO and CdR in dose-response in terms of stimulated RNA synthesis and their disparity in dose-response in terms of cytotoxic effects indicate that the systems involved in conferring protection against the lethal effects of Cd2+ are not similarly involved in attenuating the effects on RNA metabolism.

Adenosine↗
PubMed1979

Fluorescent DNA probes for flow cytometry. Considerations and prospects.

Techniques employing base specific deoxyribonucleic acid (DNA)-binding fluorochromes and flow cytometry (FCM) are potentially useful for obtaining information of the compositional features of chromatin or chromosomes of mammalian cells. Fluorescent compounds which form complexes preferentially at the A-T rich regions (i.e., DNA-reactive Hoechst dyes) or the G-C rich regions (i.e., mithramycin, chromomycin, olivomycin) in DNA are available and compatible with current FCM technology as are other compounds (i.e., ethidium bromide, propidium iodide) which show little or no base specificity and bind by intercalation in the double stranded regions of helical DNA. Energy transfer between appropriate DNA-bound dyes is a reflection of the quantity and proximity of regions containing the respective base pair segments. Since extrinsic fluorescent probes provide only a measure of available binding sites or regions unobstructed by chromatin-associated or chromosomal-associated proteins, interpretations of fluorescence measurements need to be substantiated by adequate control measures.

Animals↗