Fig. 1
Islet cell viability after 24-hr culturing at different media oxygen concentrations. Islets were incubated for 24 hr at declining oxygen concentrations: (A) 21% O2; (B) 5% O2; and (C) 1% O2. Cell viability was determined by staining with Hoechst 33342 and propidium iodide, followed by fluorescence microscopy. The nuclei of viable cells are blue, nuclei with pink fluorescence represent necrotic cells, and the nuclei of apoptotic cells should be condensed and fragmented and appear light blue or even white (not seen in this picture, 23).