A hybrid feature selection approach for the early diagnosis of Alzheimer's disease

Objective. Recently, significant advances have been made in the early diagnosis of Alzheimer’s disease from EEG. However, choosing suitable measures is a challenging task. Among other measures, frequency Relative Power and loss of complexity have been used with promising results. In the present study we investigate the early diagnosis of AD using synchrony measures and frequency Relative Power on EEG signals, examining the changes found in different frequency ranges. Approach. We first explore the use of a single feature for computing the classification rate, looking for the best frequency range. Then, we present a multiple feature classification system that outperforms all previous results using a feature selection strategy. These two approaches are tested in two different databases, one containing MCI and healthy subjects (patients age: 71.9 ± 10.2, healthy subjects age: 71.7 ± 8.3), and the other containing Mild AD and healthy subjects (patients age: 77.6 ± 10.0; healthy subjects age: 69.4± 11.5). Main Results. Using a single feature to compute classification rates we achieve a performance of 78.33% for the MCI data set and of 97.56 % for Mild AD. Results are clearly improved using the multiple feature classification, where a classification rate of 95% is found for the MCI data set using 11 features, and 100% for the Mild AD data set using 4 features. Significance. The new features selection method described in this work may be a reliable tool that could help to design a realistic system that does not require prior knowledge of a patient's status. With that aim, we explore the standardization of features for MCI and Mild AD data sets with promising results

Frequency and clinical impact of CDKN2A/ARF/CDKN2B gene deletions as assessed by in-depth genetic analyses in adult T cell acute lymphoblastic leukemia

© The Author(s).Recurrent deletions of the CDKN2A/ARF/CDKN2B genes encoded at chromosome 9p21 have been described in both pediatric and adult acute lymphoblastic leukemia (ALL), but their prognostic value remains controversial, with limited data on adult T-ALL. Here, we investigated the presence of homozygous and heterozygous deletions of the CDKN2A/ARF and CDKN2B genes in 64 adult T-ALL patients enrolled in two consecutive trials from the Spanish PETHEMA group. Alterations in CDKN2A/ARF/CDKN2B were detected in 35/64 patients (55%). Most of them consisted of 9p21 losses involving homozygous deletions of the CDKNA/ARF gene (26/64), as confirmed by single nucleotide polymorphism (SNP) arrays and interphase fluorescence in situ hybridization (iFISH). Deletions involving the CDKN2A/ARF/CDKN2B locus correlated with a higher frequency of cortical T cell phenotype and a better clearance of minimal residual disease (MRD) after induction therapy. Moreover, the combination of an altered copy-number-value (CNV) involving the CDKN2A/ARF/CDKN2B gene locus and undetectable MRD (≤ 0.01%) values allowed the identification of a subset of T-ALL with better overall survival in the absence of hematopoietic stem cell transplantation.This project was supported by the Asociación Española Contra el Cáncer, AECC (project ref.: GC16173697BIGA), by CERCA Program/Generalitat de Catalunya, the Catalan Government: 2014-SGR225 (GRE), Obra Social “La Caixa” and by Celgene Spain. E. Genescà is the recipient of agrant from the Spanish Health Ministry (ISCIII, CA12/00468) and an unrestricted grant from Gilead.A. Gonzalez-Perez is supported by a Ramon y Cajal fellowship (RYC-2013-14554) of the Educational Ministry (Madrid, Spain). This work was also partially supported by FEDER funds from the ISCIII (PT13/0010/0026, CIBERONC (CB16/12/00284 and CB16/12/00400), Madrid, Spain)

Frequency and clinical impact of CDKN2A/ARF/CDKN2B gene deletions as assessed by in-depth genetic analyses in adult T cell acute lymphoblastic leukemia

Altres ajuts: This project was supported by the Asociación Española Contra el Cáncer, AECC (project ref.: GC16173697BIGA), Obra Social "La Caixa" and by Celgene Spain. A. Gonzalez-Perez is supported by a Ramon y Cajal fellowship (RYC-2013-14554) of the Educational Ministry (Madrid, Spain). This work was also partially supported by FEDER funds from CIBERONC (CB16/12/00284 and CB16/12/00400), Madrid, Spain).Recurrent deletions of the CDKN2A/ARF/CDKN2B genes encoded at chromosome 9p21 have been described in both pediatric and adult acute lymphoblastic leukemia (ALL), but their prognostic value remains controversial, with limited data on adult T-ALL. Here, we investigated the presence of homozygous and heterozygous deletions of the CDKN2A/ARF and CDKN2B genes in 64 adult T-ALL patients enrolled in two consecutive trials from the Spanish PETHEMA group. Alterations in CDKN2A/ARF/CDKN2B were detected in 35/64 patients (55%). Most of them consisted of 9p21 losses involving homozygous deletions of the CDKNA/ARF gene (26/64), as confirmed by single nucleotide polymorphism (SNP) arrays and interphase fluorescence in situ hybridization (iFISH). Deletions involving the CDKN2A/ARF/CDKN2B locus correlated with a higher frequency of cortical T cell phenotype and a better clearance of minimal residual disease (MRD) after induction therapy. Moreover, the combination of an altered copy-number-value (CNV) involving the CDKN2A/ARF/CDKN2B gene locus and undetectable MRD (≤ 0.01%) values allowed the identification of a subset of T-ALL with better overall survival in the absence of hematopoietic stem cell transplantation

Bacterial community composition characterization of a lead-contaminated Microcoleus sp. consortium

International audienceIntroduction: A Microcoleus sp. consortium, obtained from the Ebro delta microbial mat, was maintained under different conditions including uncontaminated, lead-contaminated, and acidic conditions. Materials and methods: Terminal restriction fragment length polymorphism and 16S rRNA gene library analyses were performed in order to determine the effect of lead and culture conditions on the Microcoleus sp. consortium. Results: The bacterial composition inside the consortium revealed low diversity and the presence of specific terminal-restriction fragments under lead conditions. 16S rRNA gene library analyses showed that members of the consortium were affiliated to the Alpha, Beta, and Gammaproteobacteria and Cyanobacteria. Sequences closely related to Achromobacter spp., Alcaligenes faecalis, and Thiobacillus species were exclusively found under lead conditions while sequences related to Geitlerinema sp., a cyanobacterium belonging to the Oscillatoriales, were not found in presence of lead. Discussion: This result showed a strong lead selection of the bacterial members present in the Microcoleus sp. consortium. Several of the 16S rRNA sequences were affiliated to nitrogen-fixing microorganisms including members of the Rhizobiaceae and the Sphingomonadaceae. Additionally, confocal laser scanning microscopy and scanning and transmission electron microscopy showed that under lead-contaminated condition Microcoleus sp. cells were grouped and the number of electrodense intracytoplasmic inclusions was increase

Vertical migration of phototrophic bacterial populations in a hypersaline microbial mat from Salins-de-Giraud (Camargue, France)

International audienceThe spatio-temporal distribution of phototrophic communities of the hypersaline photosynthetic Camarguc microbial mat (Salins-de-Giraud, France) was investigated over a diel cycle by combining microscopic and molecular approaches. Microcoleus chthonoplastes and Halomicronema excentricum, the dominant cyanobacteria of this oxyphotrophic community, were observed with confocal laser scanning microscopy to determine their biomass profiles. Both bacteria have similar vertical distributions, varying from a homogenous distribution through the mat during the night, to a specific localization in the upper oxic zone of 1.5 mm during the day. Terminal restriction fragment length polymorphism of PCR-amplified pufM gene fragments revealed three groups of anoxyphototrophic populations, which varied according to the two opposite periods of the diel cycle under study. They were either specifically detected in only one period, or homogenously distributed through the mat in all periods, or located in specific zones of the mat depending on the period considered. Oxygen concentrations, pH and biomass of the major filamentous cyanobacteria were the determinative factors in the distribution of these anoxyphototrophs across the mat. Thus, vertical migration, cell-cell aggregate formation and metabolic switches were the most evident defence of the photosynthetic populations against the adverse effects of sulfide and oxygen fluxes during a diel cycle

Isolation and identification of a bacterium with high tolerance to lead and copper from a marine microbial mat in Spain

International audienceA bacterial strain (DE2008) was isolated from a consortium of microorganisms living in the microbial mats of the Ebro Delta with the ability to grow under conditions of high concentrations of lead and copper. Strain DE2008 has been characterized by microscopic and metabolic techniques and identified by sequencing of PCR-amplified 16S rRNA gene fragments as Micrococcus luteus. The strain is highly resistant to lead and copper. Micrococcus luteus DE2008 grew optimally until levels of 1 mM of Pb(NO3)2 and CuSO4, respectively, and was completely inhibited at 3 mM Pb(NO 3)2 and at 1.5 mM CuSO4. Elemental analysis determined by energy-dispersive X-ray spectroscopy (EDX) coupled with scanning electron microscopy and transmission electron microscopy from polluted cultures of DE2008 show that this microorganism can biosorpt Pb and Cu in exopolysaccharide envelopes, without accumulating them inside the cell