An intragenic ERG deletion is a marker of an oncogenic subtype of B-cell precursor acute lymphoblastic leukemia with a favorable outcome despite frequent IKZF1 deletions.

Oncogenic subtypes in childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL) are used for risk stratification. However, a significant number of BCP-ALL patients are still genetically unassigned. Using array-comparative genomic hybridization in a selected BCP-ALL cohort, we characterized a recurrent V(D)J-mediated intragenic deletion of the ERG gene (ERG(del)). A breakpoint-specific PCR assay was designed and used to screen an independent non-selected cohort of 897 children aged 1-17 years treated for BCP-ALL in the EORTC-CLG 58951 trial. ERG(del) was found in 29/897 patients (3.2%) and was mutually exclusive of known classifying genetic lesions, suggesting that it characterized a distinct leukemia entity. ERG(del) was associated with higher age (median 7.0 vs. 4.0 years, P=0.004), aberrant CD2 expression (43.5% vs. 3.7%, P<0.001) and frequent IKZF1 Δ4-7 deletions (37.9% vs. 5.3%, P<0.001). However, ERG(del) patients had a very good outcome, with an 8-year event-free survival (8-y EFS) and an 8-year overall survival of 86.4% and 95.6%, respectively, suggesting that the IKZF1 deletion had no impact on prognosis in this genetic subtype. Accordingly, within patients with an IKZF1 Δ4-7 deletion, those with ERG(del) had a better outcome (8-y EFS: 85.7% vs. 51.3%; hazard ratio: 0.16; 95% confidence interval: 0.02-1.20; P=0.04). These findings have implications for further stratification including IKZF1 status.

[The traumatic passage of migrant children at school]. / La traversée traumatique d'un enfant migrant à l'école.

INTRODUCTION: At school, the migrant child has to face an intense symbolization that articulates the experience of migration, the family past and the availability of the school environment to accommodate beyond its primary mission of education. Migration is a potential source of trauma. This article aims to show the complexity of the processes involved in the psyche of the child and discusses aspects of latency as well as intercultural issues. METHOD: The study was conducted on the psychological examination of a 7-year old migrant child that we met at school. The meetings took place because of difficulties for the child, highlighted by the school. The data are from interviews with the child's teacher and the mother of the child, as well as the projective methods available to the child, the Rorschach test and the game Play Mobile. Both tools have been used as a method of investigation and as a support for mediation. RESULTS: Media and projective interviews reveal the mother's lack of understanding of behavioral problems of children. The mother appeared to be emotionally unavailable for her son. She had a lot of difficulty in containing him. As for the child, he tried to maintain the presence of an absent father, portrayed the story of his immigration and his growing awareness of the processes involved. The child invested the clinical relationship and expressed every effort to symbolize the experience of pre-migration and migration times. DISCUSSION: The analysis reveals different types of passages: family passage, institutional passage, and projective passage that requires a mental reorganization of previous experiences. It appears that the environment is very important in the psychological construction of the child. The difficulty of investing school knowledge comes from a lack of evidence of his personal history. The discussion raises some issues of migration latency period as well as some problems with changing cultural context. To symbolize and build an intercultural Me, the migrant child needs to rely on stable environments.

Outer-membrane proteomic maps and surface-exposed proteins of Legionella pneumophila using cellular fractionation and fluorescent labelling.

Bacterial surface-associated proteins play crucial roles in host-pathogen interactions and pathogenesis. The identification of these proteins represents an important goal of bacterial proteomics for vaccine development, but also for environmental concerns such as microbial biosensing. Here, we developed such an approach for Legionella pneumophila, a bacterium that causes severe pneumonia. We propose a complementary strategy consisting of (1) a fluorescent labelling of surface-exposed proteins in parallel with (2) a fractionation of the outer-membrane protein extract. These two distinct protein populations were subsequently separated using two-dimensional gel electrophoresis and characterised by mass spectrometry. Within these populations, we found proteins which were expected for the compartments studied, but also a great number of proteins never experimentally described, and also a non-negligible fraction of proteins never described in these fractions. These data provided new routes of inspection for transport and host recognition for Legionella pneumophila. In addition, these results on the membranome and surfaceome show that Legionella in the stationary phase of growth possesses the major determinants to infect host cells.

Sequential activation of constitutive and inducible nitric oxide synthase (NOS) in rat cerebellar granule neurons by pseudomonas fluorescens and invasive behaviour of the bacteria.

Previous studies have shown that Pseudomonas fluorescens and its lipopolysaccharide (LPS) exert dose-related cytotoxic effects on neurons and glial cells. In the present work, we investigated the time course effect of P. fluorescens MF37 and its LPS on cultured rat cerebellar granule neurons. The kinetics of binding of P. fluorescens to cerebellar granule neurons is rapid and reaches a mean of 3 bacteria/cell after 5 h. As demonstrated by measurement of the concentration of nitrite in the culture medium, P. fluorescens induces a rapid stimulation (3 h) of the nitric oxide synthase (NOS) activity of the cells. In contrast, LPS extracted from P. fluorescens requires a long lag phase (24 h) before observation of an activation of NOS. Measurement of the membrane resting potential of granule neurons showed that within 3 h of incubation there was no difference of effect between the action of P. fluorescens and that of its endotoxin. Two complementary approaches allowed to demonstrate that P. fluorescens MF37 presents a rapid invasive behaviour suggesting a mobilisation of calcium in its early steps of action. The present study reveals that P. fluorescens induces the sequential activation of a constitutive calcium-dependent NOS and that of an inducible NOS activated by LPS. Our results also suggest that in P. fluorescens cytotoxicity and invasion are not mutually exclusive events.