Figure 1.

Mean change (Δ) in carbon monoxide (CO) to carbon dioxide (CO₂) ratio in separate collections of exhaled breath of individual BALB/c mice injected with 250 µg (n = 4), 50 µg (n = 3), or no (n = 3) Escherichia coli lipopolysaccharide (LPS) at hour 0. The error bars are 95% confidence intervals (CIs). There were no samples at hours 73 and 121 from a mouse that received the 250-µg dose and died after the hour 49 collection. The inset in the upper right corner shows the analysis of variance least square means (with 95% CIs) for combined CO/CO₂ values taken at 10, 25, and 30 hours after injection of LPS from the 3 groups of mice. The F statistic and coefficient of determination (R²) are shown.