RESUMO
Surgical bypass grafts are commonly used retrograde conduits to facilitate chronic total occlusion (CTO) percutaneous coronary intervention (PCI). While extensive experience exists using saphenous vein grafts as retrograde conduits in CTO PCI, information on the utilization of arterial grafts is more limited. In particular, the gastroepiploic artery (GEA) is a very uncommonly used arterial graft in contemporary bypass surgery and its role for retrograde CTO recanalization has received little study. We describe a case of right coronary artery CTO that was recanalized using the retrograde approach via a GEA graft to the posterior descending artery and highlight the specific challenges of this approach.
RESUMO
Despite an increase in survival for children with acute lymphoblastic leukemia (ALL), the outcome after relapse is poor. To understand the genetic events that contribute to relapse and chemoresistance and identify novel targets of therapy, 3 high-throughput assays were used to identify genetic and epigenetic changes at relapse. Using matched diagnosis/relapse bone marrow samples from children with relapsed B-precursor ALL, we evaluated gene expression, copy number abnormalities (CNAs), and DNA methylation. Gene expression analysis revealed a signature of differentially expressed genes from diagnosis to relapse that is different for early (< 36 months) and late (≥ 36 months) relapse. CNA analysis discovered CNAs that were shared at diagnosis and relapse and others that were new lesions acquired at relapse. DNA methylation analysis found increased promoter methylation at relapse. There were many genetic alterations that evolved from diagnosis to relapse, and in some cases these genes had previously been associated with chemoresistance. Integration of the results from all 3 platforms identified genes of potential interest, including CDKN2A, COL6A2, PTPRO, and CSMD1. Although our results indicate that a diversity of genetic changes are seen at relapse, integration of gene expression, CNA, and methylation data suggest a possible convergence on the WNT and mitogen-activated protein kinase pathways.