Figure 1

Heat map and calculated difference from distance from reference (DFR) for polymorphonuclear neutrophil (PMN) genome-wide expression. Using a false discovery adjusted probability of <0.001 and a two-fold difference in expression, the temporal pattern of the expression of the trauma responsive genes that differed between the matched aged (≥55 years) and young (<55 years old) trauma cohorts with complicated outcomes, as well as healthy controls, is presented. (A) Cluster analysis of the cohorts 0.5 days after injury showed that there were 3,121 probe sets (2,095 genes) with expression that was significant expressed among groups (F-test, P <0.001). In addition, the overall pattern of gene expression was significantly different in each cohort, as determined by leave one out cross-validation. (B) Summary of the DFR score calculated for each patient in the complicated aged and young cohorts at days 0.5, one and four days after injury. Analysis revealed significant differences in the DFRs at all the post trauma time points between the two cohorts when compared to controls. In addition, the advanced age cohort had significantly more aberrant gene expression as compared to the young patients on day 4 (Newman-Keuls multiple comparison test, * P <0.05).