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In this paper, we study the relationship between vectorial (Boolean) functions and cyclic codes in the context of algebraic attacks. We first derive a direct link between the annihilators of a vectorial function (in univariate form) and certain 2 n -ary cyclic codes (which we show that they are LCD codes). We also present some properties of those cyclic codes as well as their weight enumerator. In addition, we generalize the so-called algebraic complement and study its properties. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the homogeneous weight and homogeneous Gray map over the ring $$R_{q}=\mathbb {F}_{2}[u_{1},u_{2},\ldots ,u_{q}]{/}\left\langle u_{i}^{2}=0,u_{i}u_{j}=u_{j}u_{i}\right\rangle $$ for $$q \ge 1$$ . We also consider the construction of simplex and MacDonald codes of types $$\alpha $$ and $$\beta $$ over this ring and their covering radius. [ABSTRACT FROM AUTHOR]

In this paper, we define the simplex and MacDonald codes of types $$\alpha $$ and $$\beta $$ over $${\mathbb {Z}}_{2}{\mathbb {Z}}_{4}$$ . We also examine the covering radii of these codes. Further, we study the binary images of these codes and prove that the binary image of the simplex codes of type $$\alpha $$ meets the Gilbert bound. [ABSTRACT FROM AUTHOR]

The intestinal microbiota plays a key role in the pathogenesis of acute graft-versus-host disease (aGVHD). High-dose conditioning regimens given prior to allogeneic hematopoietic stem cell transplantation (aHSCT) modulate the composition of gut microbiota and damage the gut epithelial barrier, resulting in increased systemic inflammation. We assessed whether gut decontamination with antibiotics (ATB) prior to aHSCT influenced the frequency of aGVHD and mortality in 500 patients from two Canadian centers between 2005 and 2012. The rate of grade II-IV aGVHD was higher in the ATB arm compared with the arm without ATB (42% vs 28%; p < 0.001). This difference was mainly driven by a 2-fold higher rate of grade II-IV gastrointestinal aGVHD (GI-GVHD) in the ATB arm compared with the arm without ATB (20.7% vs 10.8%; p = 0.003). Multivariate analyses adjusted for known aGVHD risk factors revealed that more patients in the ATB group developed clinically significant GI-GVHD and liver aGVHD; adjusted odds ratio (aOR) = 1.83; p = 0.023 and aOR = 3.56; p = 0.047, respectively. Importantly, median overall survival (OS) was significantly lower in the group receiving ATB and the OS at 10 y remained decreased in the ATB group; adjusted hazard ratio (aHR) = 1.61 ( p < 0.001). Without undermining the role of ATB prophylaxis to prevent infection in aHSCT, we have shown that the use of ATB that targets intestinal bacteria is associated with a more severe aGVHD that involves the GI organs and impacts OS. Prospective studies that evaluate the contribution of bacterial decontamination to aGVHD are warranted.

Isolated 20q deletion is common in MDS and considered of good prognosis, but no large series have been reported. We compared characteristics of 62 MDS patients with isolated del 20q, 36 patients with del 20q and other cytogenetic abnormalities, and 1335 MDS patients without del20q. Significant differences between MDS with isolated del 20q and patients without del 20q were lower platelet count (mean 144 vs. 196 G/l, p=0.005), lower marrow blast count (mean 3.9% vs. 5.6%, p=0.0008), and higher reticulocyte count (mean 72.5 vs. 51.7 G/l, p=0.04). Ten (16%) patients with isolated del 20q had Hb>12 g/dl and platelets <100 G/l, compared to 7.3% of patients without del 20q (p=0.025). Review of marrow slides of those 10 patients showed that could be readily identified as MDS prior to cytogenetics. Fourteen percent of patients with isolated del 20q progressed to AML compared to 11% with one and 24% with several additional abnormalities. Median survival was 54 months in patients with isolated del 20q, not reached and 12 months for del 20q with one and several additional abnormalities, respectively (p=0.035) confirming the favorable prognosis of del 20q without complex abnormalities., (Copyright © 2011 Elsevier Ltd. All rights reserved.)