TABLE 1.

Chromosome aberrations of Pu-27-treated U937 cells

# represents the number of the experiment.

Sample	Total metaphase studied	Abnormal metaphase	Chromatid breaks	Chromosome breaks	Cells with radials and extensive breaks	Frequency of metaphases with simple break
U937 control #1	103	3 (2.9%)	1 (1.0%)	0	1 (1.0%)	0.02
U937 control #2	93	3 (3.2%)	0	0	3 (3.2%)	0
U937 Pu-27#1 (day 2)	77	37 (48.1%)	14 (18.2%)	3 (3.9%)	20 (26.0%)	0.30
U937 Pu-27#2 (day 2)	68	43 (63.2%)	11 (16.2%)	3 (4.4%)	27 (39.7%)	0.39
U937 Pu-27#1 (day 5)	120	40 (33.3%)	7 (5.8%)	12 (10%)	21 (17.5%)	0.23
U937 Pu-27#2 (day 5)	88	28 (31.8%)	12 (13.6%)	3 (3.4%)	10 (11.4%)	0.23