Entity

Time filter

Source Type


Ambroise J.,Catholic University of Louvain | Irenge L.,Catholic University of Louvain | Savov E.,Military Medical Academy of Sofia | Robert A.,Catholic University of Louvain | Gala J.L.,Catholic University of Louvain
Bioinformatics | Year: 2014

Motivation: Pyrosequencing is a cost-effective DNA sequencing technology that has many applications, including rapid genotyping of a broad spectrum of bacteria. When molecular typing requires to genotype multiple DNA stretches, several pyrosequencing primers could be used simultaneously but this would create overlapping primer-specific signals, which are visually uninterpretable. Accordingly, the objective was to develop a new method for signal processing (AdvISER-M-PYRO) to automatically analyze and interpret multiplex pyrosequencing signals. In parallel, the nucleotide dispensation order was improved by developing the SENATOR ('SElecting the Nucleotide dispensATion Order') algorithm. Results: In this proof-of-concept study, quintuplexpyrosequencing was applied on eight bacterial DNA and targeted genetic alterations underlying resistance to β-lactam antibiotics. Using SENATOR-driven dispensation order, allgenetic variants (31 of 31; 100%)werecorrectly identified with AdvISER-M-PYRO Among nine expected negative results, there was only one false positive that was tagged with an 'unsafe' label. Availability and implementation: SENATOR and AdvISER-M-PYRO are implemented in the AdvISER-M-PYRO R package (http://sites. uclouvain.be/md-ctma/index.php/softwares) and can be used to improve the dispensation order and to analyze multiplex pyrosequencing signals generated in a broad range of typing applications. © The Author 2014. Published by Oxford University Press. All rights reserved.


Ambroise J.,Catholic University of Louvain | Savov E.,Military Medical Academy of Sofia | Marinescu D.,Bucharest Clinical Emergency Hospital | Chirimwami R.B.,Catholic University of Bukavu | Gala J.-L.,Catholic University of Louvain
AMB Express | Year: 2015

Rapid and specific detection of extended-spectrum β-lactamase-producing (ESBL) bacteria is crucial both for timely antibiotic therapy when treating infected patients as well as for appropriate infection control measures aimed at curbing the spread of ESBL-producing isolates. Whereas a variety of phenotypic methods are currently available for ESBL detection, they remain time consuming and sometimes difficult to interpret while being also affected by a lack of sensitivity and specificity. Considering the longer turnaround time (TAT) of susceptibility testing and culture results, DNA-based ESBL identification would be a valuable surrogate for phenotypic-based methods. Putative ESBL-positive Enterobacteriaceae isolates (n = 330) from clinical specimen were prospectively collected in Bulgaria, Romania and Democratic Republic of Congo and tested in this study. All isolates were assessed for ESBL-production by the E-test method and those giving undetermined ESBL status were re-tested using the combination disk test. A genotypic assay successively combining qPCR detection of blaCTX-M, blaTEM and blaSHV genes with a multiplex pyrosequencing of blaTEM and blaSHV genes was developed in order to detect the most common ESBL-associated TEM and SHV single nucleotides polymorphisms, irrespective of their plasmid and/or chromosomal location. This assay was applied on all Enterobacteriaceae isolates (n = 330). Phenotypic and genotypic results matched in 324/330 (98.2%). Accordingly, real-time PCR combined with multiplex pyrosequencing appears to be a reliable and easy-to-perform assay with high-throughput identification and fast TAT (~5 h). © 2015, Deccache et al.


Petkov G.,Research Foundation Epilepsy Institute the Netherlands SEIN | Mladenov N.,Military Medical Academy of Sofia | Kalitzin S.,Research Foundation Epilepsy Institute the Netherlands SEIN
Integrated Computer-Aided Engineering | Year: 2013

In the present work the problem of reconstructing locations of events in an arbitrary scene, or world (for example 3D scene in real applications) from an over-complete set of measurements, typically of lower dimension each (such as multiple 2D images obtained from different cameras) is addressed. A non-parametric approach based on Principal Component Analysis (PCA) has been developed where a training set of points with known world-coordinates is used to reconstruct the forward and inverse transformation matrices from the scene to the measurement space. The technique does not use any a priori information about the data acquisition geometry or its parameters and can also identify degenerate cases where either the training or the measurement sets are insufficient to perform robust reconstruction. As a first illustration a simple test-set of objects and their 2D images has been presented in order to illustrate the validity of the method. The next realistic application involves a data set of explosions recorded from two high-speed cameras. The method successfully reconstructs the positions of the explosions and in addition their intensities were also quantified. © 2013-IOS Press and the author(s). All rights reserved.


Irenge L.M.,Catholic University of Louvain | Savov E.,Military Medical Academy of Sofia | Ariciuc M.,Bucharest Clinical Emergency Hospital | Macovei A.,Bucharest Clinical Emergency Hospital | And 5 more authors.
Journal of Microbiological Methods | Year: 2011

Rapid and reliable assessment of Acinetobacter baumannii resistance to quinolones was successfully achieved through pyrosequencing of the gyrA and parC quinolone-resistance determining regions. A strong correlation was found between quinolone resistance and mutations in gyrA codon 83 and/or in the parC gene (codons 80 or 84). Absence of QRDR mutations was associated with susceptibility to quinolones. © 2011 Elsevier B.V.


Martinova H.,Medical University-Sofia | Ganev I.,Military Medical Academy of Sofia | Milanova V.,Medical University-Sofia | Voynov L.,Military Medical Academy of Sofia | And 5 more authors.
Biotechnology and Biotechnological Equipment | Year: 2016

The aim of this study was to approbate the Bulgarian version of the international instrument for evaluation of temperamental traits, TEMPS-A (Temperament Evaluation of the Memphis, Pisa, Paris, and San Diego –Autoquestionnaire), and to prove the need to include it in the instruments for research and diagnosis of personality. The study included 901 subjects, 540 of whom are healthy volunteers. One month after the initial test, 118 subjects from the control group were retested with a set of clinical tools to check the reliability of the instrument (temporal stability). The TEMPS-A scales showed high test–retest reliability and high internal consistency. The number of scales was verified and the construct validity of the Bulgarian version of TEMPS-A was confirmed. The results outline the limit for predictive scores on the axis normal–pathological values. The observed correlations did not prove a causal link between the measured variables but verified a statistically significant correlation between the TEMPS-A and Eysenck Personality Questionnaire results, which proved that the two instruments measure the same basic personality characteristics, namely the temperamental construct. The analysis verified the successful standardization and approbation of the Bulgarian version of TEMPS-A for Bulgaria. The comparative analysis of a group of 74 persons serving custodial sentence on the territory of Bulgaria and a control group (N = 74) showed statistically significant differences between the mean scores in the two groups on all TEMPS-A scales, except for hyperthymic temperament, suggesting that delinquent behaviour is connected with an individual's temperamental characteristics. © 2016 The Author(s). Published by Taylor & Francis.

Discover hidden collaborations