Genuer V.,University Grenoble alpes |
Genuer V.,CEA Grenoble |
Gal O.,French Atomic Energy Commission |
Meteau J.,University Grenoble alpes |
And 10 more authors.
Progress in Biomedical Optics and Imaging - Proceedings of SPIE
We report here on the ability of elastic light scattering in discriminating Gram+, Gram- and yeasts at an early stage of growth (6h). Our technique is non-invasive, low cost and does require neither skilled operators nor reagents. Therefore it is compatible with automation. It is based on the analysis of the scattering pattern (scatterogram) generated by a bacterial microcolony growing on agar, when placed in the path of a laser beam. Measurements are directly performed on closed Petri dishes. The characteristic features of a given scatterogram are first computed by projecting the pattern onto the Zernike orthogonal basis. Then the obtained data are compared to a database so that machine learning can yield identification result. A 10-fold cross-validation was performed on a database over 8 species (15 strains, 1906 scatterograms), at 6h of incubation. It yielded a 94% correct classification rate between Gram+, Gram- and yeasts. Results can be improved by using a more relevant function basis for projections, such as Fourier-Bessel functions. A fully integrated instrument has been installed at the Grenoble hospital's laboratory of bacteriology and a validation campaign has been started for the early screening of MSSA and MRSA (Staphylococcus aureus, methicillin-resistant S. aureus) carriers. Up to now, all the published studies about elastic scattering were performed in a forward mode, which is restricted to transparent media. However, in clinical diagnostics, most of media are opaque, such as blood-supplemented agar. That is why we propose a novel scheme capable of collecting back-scattered light which provides comparable results. © 2016 SPIE. Source
Dasse R.,Lille 2 University of Health and Law |
Dasse R.,Laboratoire dimmunologie et hematologie du CHU Cocody |
Lefranc D.,Lille 2 University of Health and Law |
Dubucquoi S.,Lille 2 University of Health and Law |
And 6 more authors.
Interdisciplinary Perspectives on Infectious Diseases
Background. Absence of acquired protective immunity in endemic areas children leads to higher susceptibility to severe malaria. To investigate the involvement of regulatory process related to self-reactivity, we evaluated potent changes in auto-antibody reactivity profiles in children and older subjects living in malaria-endemic zones comparatively to none-exposed healthy controls. Methods. Analysis of IgG self-reactive footprints was performed using Western blotting against healthy brain antigens. Plasmas of 102 malaria exposed individuals (MEIs) from endemic zone, with or without cerebral malaria (CM) were compared to plasmas from non-endemic controls (NECs). Using linear discriminant and principal component analysis, immune footprints were compared by counting the number, the presence or absence of reactive bands. We identified the most discriminant bands with respect to age and clinical status. Results. A higher number of bands were recognized by IgG auto-antibodies in MEI than in NEC. Characteristic changes in systemic self-IgG-reactive repertoire were found with antigenic bands that discriminate Plasmodium falciparum infections with or without CM according to age. 8 antigenic bands distributed in MEI compared with NEC were identified while 6 other antigenic bands were distributed within MEI according to the age and clinical status. Such distortion might be due to evolutionary processes leading to pathogenic/protective events. Copyright © 2011 Romuald Dassé et al. Source
Tremeaux P.,Institute Of Biologie Et Pathologie |
Tremeaux P.,CNRS Institute of Pharmacology and Structural Biology |
Caporossi A.,Institute Of Biologie Et Pathologie |
Caporossi A.,French National Center for Scientific Research |
And 17 more authors.
Clinical Microbiology and Infection
Directly acting antiviral drugs have contributed considerable progress to hepatitis C virus (HCV) treatment, but they show variable activity depending on virus genotypes and subtypes. Therefore, accurate genotyping including recombinant form detection is still of major importance, as is the detection of resistance-associated mutations in case of therapeutic failure. To meet these goals, an approach to amplify the HCV near-complete genome with a single long-range PCR and sequence it with Roche GS Junior was developed. After optimization, the overall amplification success rate was 73% for usual genotypes (i.e. HCV 1a, 1b, 3a and 4a, 16/22) and 45% for recombinant forms RF_2k/1b (5/11). After pyrosequencing and subsequent de novo assembly, a near-full-length genomic consensus sequence was obtained for 19 of 21 samples. The genotype and subtype were confirmed by phylogenetic analysis for every sample, including the suspected recombinant forms. Resistance-associated mutations were detected in seven of 13 samples at baseline, in the NS3 (n = 3) or NS5A (n = 4) region. Of these samples, the treatment of one patient included daclatasvir, and that patient experienced a relapse. Virus sequences from pre- and posttreatment samples of four patients who experienced relapse after sofosbuvir-based therapy were compared: the selected variants seem too far from the NS5B catalytic site to be held responsible. Although tested on a limited set of samples and with technical improvements still necessary, this assay has proven to be successful for both genotyping and resistance-associated variant detection on several HCV types. © 2016 European Society of Clinical Microbiology and Infectious Diseases. Source
Bidart M.,Institute Of Biologie Et Pathologie |
Bidart M.,French Atomic Energy Commission |
Bidart M.,Joseph Fourier University |
Berger F.,Institute Of Biologie Et Pathologie |
And 5 more authors.
Annales de Biologie Clinique
During recent years clear progress has been made in support of tumor pathology. However, the treatment of metastatic disease is now a real therapeutic challenge. Among the new therapeutic strategies, blocking angiogenesis has been the subject of numerous clinical trials. However, if this approach was validated in 2004 by the approval of the first humanized anti-VEGF antibody (bevacizumab or Avastin®, Roche, 2004), the pre-clinical and clinical studies conducted in the last 5 years have moderated the enthusiasm that these therapies had led in the early 2000s. In November 2011, the US Food and drug administration (FDA) revoke the agency's approval of the breast cancer indication for Avastin® because of benefit-risk balance appears negative. This review describes successively the mechanisms of action of antiangiogenic agents, the main anti-angiogenic drugs and the theoretical advantages and practical limitations of these therapies. Source
Toussaint B.,CNRS Complex Medical Engineering Laboratory |
Toussaint B.,Institute Of Biologie Et Pathologie |
Chauchet X.,CNRS Complex Medical Engineering Laboratory |
Chauchet X.,Institute Of Biologie Et Pathologie |
And 5 more authors.
Expert Review of Vaccines
In the emerging field of active and specific cancer immunotherapy, strategies using live-attenuated bacterial vectors have matured in terms of academic and industrial development. Different bacterial species can be genetically engineered to deliver antigen to APCs with strong adjuvant effects due to their microbial origin. Proteic or DNA-encoding antigen delivery routes and natural bacterial tropisms might differ among species, permitting different applications. After many academic efforts to resolve safety and efficacy issues, some firms have recently engaged clinical trials with live Listeria or Salmonella spp. We describe here the main technological advances that allowed bacteria to become one of the most promising vectors in cancer immunotherapy. © 2013 Informa UK Ltd. Source