Genetic Variations of Interleukin-23R (1143A>G) and BPI (A645G), but Not of NOD2, Are Associated with Acute Graft-versus-Host Disease after Allogeneic Transplantation

Single nucleotide polymorphisms (SNPs) in genes of the immune system predict for aGVHD and mortality after allo-SCT. We investigated the effect of SNPs in the NOD2, BPI, and IL-23R genes on posttransplantation outcome in a cohort of 304 patients. NOD2 patient and donor genotype and BPI recipient genotype were not associated with the occurrence of aGVHD. However, IL-23R-SNP in the donor was correlated with less aGVHD. This association could be confirmed in multivariate analysis (odds ratio [OR], 0.39; P = .039), which identified in vivo T cell depletion (OR, 0.32; P < .001) and multiagent GVHD prophylaxis (OR, 0.51; P = .031) as other independent factors predicting for less-severe aGVHD. This multivariate model also revealed a trend toward less aGVHD in patients receiving a BPI G allele transplant (OR, 0.60; P = .067) and in those receiving a transplant from an HLA-matched donor (OR, 0.57; P = .058). In contrast, relapse was more frequent in patients with NOD2-SNPs (46.2% for SNP vs 33.2% for wild-type; P = .020). This association was found to be of borderline significance in multivariate analysis. Neither BPI nor IL-23R genotype predicted for relapse, and none of the investigated SNPs was correlated with 5-year overall survival. In our analysis, NOD2 SNPs did not predict aGVHD, but IL-23R(1142A>G) and BPI(A645G) SNPs appeared to be promising markers in this regard. The importance of these markers in prediction models for GVHD and relapse remain to be defined in large prospective clinical trials

An open-source software tool for the generation of relaxation time maps in magnetic resonance imaging

BACKGROUND: In magnetic resonance (MR) imaging, T1, T2 and T2* relaxation times represent characteristic tissue properties that can be quantified with the help of specific imaging strategies. While there are basic software tools for specific pulse sequences, until now there is no universal software program available to automate pixel-wise mapping of relaxation times from various types of images or MR systems. Such a software program would allow researchers to test and compare new imaging strategies and thus would significantly facilitate research in the area of quantitative tissue characterization. RESULTS: After defining requirements for a universal MR mapping tool, a software program named MRmap was created using a high-level graphics language. Additional features include a manual registration tool for source images with motion artifacts and a tabular DICOM viewer to examine pulse sequence parameters. MRmap was successfully tested on three different computer platforms with image data from three different MR system manufacturers and five different sorts of pulse sequences: multi-image inversion recovery T1; Look-Locker/ TOMROP T1; modified Look-Locker inversion recovery (MOLLI) T1; single-echo T2/ T2*; and multi-echo T2/ T2*. Computing times varied between 2 and 113 seconds. Estimates of relaxation times compared favorably to those obtained from non-automated curve fitting. Completed maps were exported in DICOM format and could be read in standard software packages used for analysis of clinical and research MR data. CONCLUSIONS: MRmap is a flexible cross-platform research tool that enables accurate mapping of relaxation times from various pulse sequences. The software allows researchers to optimize quantitative MR strategies in a manufacturer-independent fashion. The program and its source code were made available as open-source software on the internet

Assessment of mitral bioprostheses using cardiovascular magnetic resonance

<p>Abstract</p> <p>Background</p> <p>The orifice area of mitral bioprostheses provides important information regarding their hemodynamic performance. It is usually calculated by transthoracic echocardiography (TTE), however, accurate and reproducible determination may be challenging. Cardiovascular magnetic resonance (CMR) has been proven as an accurate alternative for assessing aortic bioprostheses. However, whether CMR can be similarly applied for bioprostheses in the mitral position, particularly in the presence of frequently coincident arrhythmias, is unclear. The aim of the study is to test the feasibility of CMR to evaluate the orifice area of mitral bioprostheses.</p> <p>Methods</p> <p>CMR planimetry was performed in 18 consecutive patients with mitral bioprostheses (n = 13 Hancock^®, n = 4 Labcore^®, n = 1 Perimount^®; mean time since implantation 4.5 ± 3.9 years) in an imaging plane perpendicular to the transprosthetic flow using steady-state free-precession cine imaging under breath-hold conditions on a 1.5T MR system. CMR results were compared with pressure half-time derived orifice areas obtained by TTE.</p> <p>Results</p> <p>Six subjects were in sinus rhythm, 11 in atrial fibrillation, and 1 exhibited frequent ventricular extrasystoles. CMR image quality was rated as good in 10, moderate in 6, and significantly impaired in 2 subjects. In one prosthetic type (Perimount^®), strong stent artifacts occurred. Orifice areas by CMR (mean 2.1 ± 0.3 cm²) and TTE (mean 2.1 ± 0.3 cm²) correlated significantly (r = 0.94; p < 0.001). Bland-Altman analysis showed a 95% confidence interval from -0.16 to 0.28 cm²(mean difference 0.06 ± 0.11 cm²; range -0.1 to 0.3 cm²). Intra- and inter-observer variabilities of CMR planimetry were 4.5 ± 2.9% and 7.9 ± 5.2%.</p> <p>Conclusions</p> <p>The assessment of mitral bioprostheses using CMR is feasible even in those with arrhythmias, providing orifice areas with close agreement to echocardiography and low observer dependency. Larger samples with a greater variety of prosthetic types and more cases of prosthetic dysfunction are required to confirm these preliminary results.</p