Lungs: Score for inflammatory cell infiltrate. Quantification of inflammatory cell infiltrates was expressed as the mean of cells per field at magnification of ×250, as resulting by the analysis of at least 10 different fields on each hematoxylin and eosin–stained whole-lung section (see also Brau et al²⁸ and Fayad-Kobeissi et al²⁹). Data are expressed as mean ± standard error of the mean (SEM); ∗P < .05 compared with normoxia; †P < .05 compared with vehicle.

Kidney: Score for inflammatory cell infiltrate. Quantification of inflammatory cell infiltration in renal cortex of kidney was determined in hematoxylin and eosin–stained sections using a 0 to 4 scale based on the percentage of cell infiltrates occupied area in each filed; 0 (no sign of infiltration), 1 (1%-10% of the area with cell infiltration), 2 (11%-25%); 3 (26%-50%), and 4 (50%). The mean of 15 randomly selected fields were analyzed at magnification ×400 (see also Belcher et al²² and Mpinganzima et al³⁸). Data are expressed as mean ± SEM; ∗P < .05 compared with normoxia; †P < .05 compared with vehicle.

Liver score: 0, no hepatocellular damage; 1, mild injury characterized by cytoplasmic vacuolization and focal nuclear pyknosis; 2, moderate injury with dilated sinusoids, cytosolic vacuolization, and blurring of intercellular borders; 3, moderate to severe injury with noncoagulative necrosis, abundant sinusoidal dilatation, red blood extravasation into hepatic chords, hypereosinophilia, and migration of neutrophils; 4, severe necrosis with loss of hepatic architecture, disintegration of hepatic chords, hemorrhage, and neutrophils infiltration.

Statistical analysis: the nonparametric pairwise Wilcoxon rank-sum test was used. Each group was balanced in sex (50% males, 50% female). We repeated the comparisons for males and females separately with equivalent results. Regarding the sex, our data did not show evidence of differences between males and females.