Comparative proteomic analysis of PAI-1 and TNF-alpha-derived endothelial microparticles.

Endothelium-derived microparticles (EMPs) are small vesicles released from endothelial cells in response to cell injury, apoptosis, or activation. Elevated concentrations of EMPs have been associated with many inflammatory and vascular diseases. EMPs also mediate long range signaling and alter downstream cell function. Unfortunately, the molecular and cellular basis of microparticle production and downstream cell function is poorly understood. We hypothesize that EMPs generated by different agonists will produce distinct populations of EMPs with unique protein compositions. To test this hypothesis, different EMP populations were generated from human umbilical vein endothelial cells by stimulation with plasminogen activator inhibitor type 1 (PAI-1) or tumor necrosis factor-alpha (TNF-alpha) and subjected to proteomic analysis by LC/MS. We identified 432 common proteins in all EMP populations studied. Also identified were 231 proteins unique to control EMPs, 104 proteins unique to PAI-1 EMPs and 70 proteins unique to TNF-alpha EMPs. Interestingly, variations in protein abundance were found among many of the common EMP proteins, suggesting that differences exist between EMPs on a relative scale. Finally, gene ontology (GO) and KEGG pathway analysis revealed many functional similarities and few differences between the EMP populations studied. In summary, our results clearly indicate that EMPs generated by PAI-1 and TNF-alpha produce EMPs with overlapping but distinct protein compositions. These observations provide fundamental insight into the mechanisms regulating the production of these particles and their physiological role in numerous diseases.

Initial surgical and pain management outcomes after Nuss procedure.

PURPOSE: The purpose of this article was to report surgical and pain management outcomes of the initial Nuss procedure experience at the Children's Hospital of Wisconsin (Milwaukee) and to place this experience in the context of the published literature. METHODS: The initial 118 consecutive Nuss procedures in 117 patients were retrospectively reviewed with approval of the Children's Hospital of Wisconsin human rights review board. Patient, surgical, complication, and pain descriptors were collected for each case. Statistical methods for comparison of pain strategies included the Kolmogorov-Smirnov test for normality, 1-way repeated measures analysis of variance, and paired t tests. RESULTS: Patient, surgical, and complication descriptors were comparable to other large series. Complication rates were 7% early and 25% late. Epidural success rate was 96.4%. There was 1 episode of recurrence 2 years postbar removal (n = 114). CONCLUSIONS: The institution of the Nuss procedure provides a highly desired result with significant complication rates. The ideal approach would deliver this result with lower risk. A pain service-driven epidural administration of morphine or hydromorphone with local anesthetic provides excellent analgesia for patients after Nuss procedure. The success of epidural analgesia is independent of catheter site and adjunctive medications. Ketorolac was an effective breakthrough medication.