Rently predisposed to NCD after CPB independent of surgical or anesthetic technique. This notion is certainly supported by the failure to reduce the incidence of Type 2 NCD, despite improvements in operative techniques 14. In order to improve these outcomes novel diagnostic and therapeutic techniques will need to be employed with a focus on identifying individual genetic variants associated with disease susceptibility and therapeutic response. The use of up-to-date microarray and bioinformatics analysis is an important step in beginning to address these challenges. Pre-CPB, 108 named genes were significantly regulated in 520-36-5 site patients with neurocognitive dysfunction. Several genes involved with inflammation, cell death and neurologic dysfunction were increased in patients who would later develop NCD. Systemic inflammation has been shown to contribute to neurocognitive decline after CPB 7, 15, 16. In a previous study we demonstrated PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/19848609 that while an increase in preoperative inflammatory chemokines did not affect outcome, postoperative elevations in chemokines were associated with the development of delirium after CPB 17. Chemokines act as potent immune mediators and may attract inflammatory cells, resulting in a disruption of the blood-brain barrier and cognitive dysfunction. In our current study we demonstrate an elevation in several genes associated with T-cell activation and signaling preoperatively in patients that would later develop NCD. Though these genes are not directly related to one-another in a specific pathway, bioinformatics analysis demonstrates that they do share important roles in neurologic function and cognition. SNCA is abundantly expressed in the brain and a major component of amyloid plaques in Alzheimer’s disease24. FTO, which has been shown to be inversely associated with brain volume, is also associated with Alzheimer’s disease as well as reduced verbal fluency in obese patients 25, 26. While TUBB2A is involved in microtubule and axonal guidance, SNAP29 has been shown to mediate synaptic membrane docking and may slow neurotransmitter release 28. YY1 has many roles in neuronal development and dysfunction and often plays a larger role in activating or repressing gene expression27. Interestingly, there was a relative decrease in the number of genes regulated postoperatively when comparing patients with NCD and those without. Again, these findings suggest that patients may be inherently predisposed to developing NCD after CPB. Further investigations may reveal predictive patterns in gene expression and ultimately result in improved preoperative planning and care of patients 
undergoing cardiac surgery. Limitation and Future Directions There are limitations to this study. Though our baseline patient characteristics and operative techniques were similar in this single institution study, the number of patients in the study was limited. A larger sample of patients would help provide greater insight into the RS 1 biological activity unique gene expression profiles associated with NCD and would allow for a more extensive mapping of gene pathways, as opposed to just placing genes in functional groups, as we have done. Another limitation is that we did not directly sample brain tissue for our mRNA extraction. We could not biopsy brain tissue in patients, and even if this were done it would not be feasible as a regular diagnostic or screening tool in a clinical setting. Of note, many of the regulated genes, which have been discussed in this, are associated wi.Rently predisposed to NCD after CPB independent of surgical or anesthetic technique. This notion is certainly supported by the failure to reduce the incidence of Type 2 NCD, despite improvements in operative techniques 14. In order to improve these outcomes novel diagnostic and therapeutic techniques will need to be employed with a focus on identifying individual genetic variants associated with disease susceptibility and therapeutic response. The use of up-to-date microarray and bioinformatics analysis is an important step in beginning to address these challenges. Pre-CPB, 108 named genes were significantly regulated in patients with neurocognitive dysfunction. Several genes involved with inflammation, cell death and neurologic dysfunction were increased in patients who would later develop NCD. Systemic inflammation has been shown to contribute to neurocognitive decline after CPB 7, 15, 16. In a previous study we demonstrated PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/19848609 that while an increase in preoperative inflammatory chemokines did not 
affect outcome, postoperative elevations in chemokines were associated with the development of delirium after CPB 17. Chemokines act as potent immune mediators and may attract inflammatory cells, resulting in a disruption of the blood-brain barrier and cognitive dysfunction. In our current study we demonstrate an elevation in several genes associated with T-cell activation and signaling preoperatively in patients that would later develop NCD. Though these genes are not directly related to one-another in a specific pathway, bioinformatics analysis demonstrates that they do share important roles in neurologic function and cognition. SNCA is abundantly expressed in the brain and a major component of amyloid plaques in Alzheimer’s disease24. FTO, which has been shown to be inversely associated with brain volume, is also associated with Alzheimer’s disease as well as reduced verbal fluency in obese patients 25, 26. While TUBB2A is involved in microtubule and axonal guidance, SNAP29 has been shown to mediate synaptic membrane docking and may slow neurotransmitter release 28. YY1 has many roles in neuronal development and dysfunction and often plays a larger role in activating or repressing gene expression27. Interestingly, there was a relative decrease in the number of genes regulated postoperatively when comparing patients with NCD and those without. Again, these findings suggest that patients may be inherently predisposed to developing NCD after CPB. Further investigations may reveal predictive patterns in gene expression and ultimately result in improved preoperative planning and care of patients undergoing cardiac surgery. Limitation and Future Directions There are limitations to this study. Though our baseline patient characteristics and operative techniques were similar in this single institution study, the number of patients in the study was limited. A larger sample of patients would help provide greater insight into the unique gene expression profiles associated with NCD and would allow for a more extensive mapping of gene pathways, as opposed to just placing genes in functional groups, as we have done. Another limitation is that we did not directly sample brain tissue for our mRNA extraction. We could not biopsy brain tissue in patients, and even if this were done it would not be feasible as a regular diagnostic or screening tool in a clinical setting. Of note, many of the regulated genes, which have been discussed in this, are associated wi.