Induction of epstein-barr virus (EBV) lytic cycle in vitro causes lipid peroxidation, protein oxidation and DNA damage in lymphoblastoid B cell lines

<p>Abstract</p> <p>Background</p> <p>We investigated the oxidative modifications of lipids, proteins and DNA, potential molecular targets of oxidative stress, in two lymphoblastoid cell lines: B95-8 and Raji, after EBV lytic cycle induction. Conjugated dienes level was measured as biomarker of lipid peroxidation. Malondialdehyde adduct and protein carbonyl levels, as well as protein thiol levels were measured as biomarkers of protein oxidation. DNA fragmentation was evaluated as biomarker of DNA oxidation.</p> <p>Results</p> <p>After 48 h (peak of lytic cycle), a significant increase in conjugated dienes level was observed in B95-8 and Raji cell lines (p = 0.0001 and p = 0.019 respectively). Malondialdehyde adduct, protein carbonyl levels were increased in B95-8 and Raji cell lines after EBV lytic cycle induction as compared to controls (MDA-adduct: p = 0.008 and p = 0.006 respectively; Carbonyl: p = 0.003 and p = 0.0039 respectively). Proteins thiol levels were decreased by induction in B95-8 and Raji cell lines (p = 0.046; p = 0.002 respectively). DNA fragmentation was also detected in B95-8 and Raji cell lines after EBV lytic cycle induction as compared to controls.</p> <p>Conclusion</p> <p>The results of this study demonstrate the presence of increased combined oxidative modifications in lipids, proteins in B95-8 and Raji cells lines after EBV lytic cycle induction. These results suggest that lipid peroxidation, protein oxidation and DNA fragmentation are generally induced during EBV lytic cycle induction and probably contribute to the cytopathic effect of EBV.</p

Modélisation centrée sur l'acteur dans une approche e-veille : analyse de corpus sur les nanotechnologies

International audienceThis article illustrates the architecture of a watching system that meets the one hand, the specific needs of the watcher, and on the other hand, it presents a generic view on the various projects in progress to provide a global vision of results. The generic architecture is focused on the needs and preferences of different watchers. In our approach, modeling and classification of different information exchanged throughout the watching process have been proposed in knowledge management.Cet article illustre l'architecture d'un système de veille qui répond, d'un côté, à des besoins spécifiques du veilleur et, d'un autre côté, il présente une vue générique sur les différents projets en cours afin de donner une vision globale des résultats. L'architecture générique est centrée sur les besoins et les préférences de différents acteurs de veille. Dans notre approche, la modélisation et la hiérarchisation des différentes informations échangées tout au long du processus de veille ont été projetées en gestion des connaissances

From information to decision: information management methodology in decisional process

International audienceA company uses several watch types for different needs. The main idea is to offer a generic watch system that meets various needs and can be adapted to many structures of watch process. We present, in this paper, these various watch process from information management to added-value information. Also, we describe the divergences in the watcher organizations with the knowledge presentations. Finally, we propose the architecture for our generic watch system

Lipid peroxidation, proteins modifications, anti-oxidant enzymes activities and selenium deficiency in the plasma of hashitoxicosis patients

Objectives: The aim of this study was to explore the oxidative stress profile in hashitoxicosis (HTX) and to compare it with that of healthy subjects. Patients and methods: Spectrophotometric methods were used to evaluate the oxidative stress markers. The selenium level was investigated by atomic absorption. Results: High levels of thiobarbituric acid reactive species (TBARS) and conjugated dienes were found in HTX patients ( p = 0.034 and p = 0.043, respectively) compared with healthy controls. For antioxidant enzymes, superoxide dismutase (SOD) and catalase activities increased, whereas that of glutathione peroxidase (GPx) decreased ( p = 0.000, p = 0.014, p = 0.000, respectively) compared with controls. A reduction in the level of selenium ( p = 0.029) and thiol groups ( p = 0.008) were shown in patients; however, levels of carbonyl group and malondialdehyde (MDA) protein adducts decreased ( p = 0.000) compared with controls. Positive correlation was shown between levels of free thyroxine (FT4) and TBARS ( r = 0.711, p = 0.048) and between FT4 level and SOD activity ( r = 0.713, p = 0.047). Conversely, GPx activity presented a negative correlation with FT4 and free triiodothyronine (FT3) levels ( r = –0.934, p = 0.001; r = –0.993, p = 0.000, respectively). In addition, GPx activity showed positive correlation with selenium level ( r = 0.981, p = 0.019) and the FT3 level correlated negatively with the level of thiol groups ( r = –0.892, p = 0.017). Conclusions: This study shows the presence of an oxidative stress and selenium deficiency in HTX patients and suggests that the hyperthyroid state is strongly implicated in the establishment of this disturbed oxidative profile

Adaptive functional reorganization in amyotrophic lateral sclerosis: coexisting degenerative and compensatory changes

International audienceBackground and purpose: Considerable functional reorganization takes place in amyotrophic lateral sclerosis (ALS) in face of relentless structural degeneration. This study evaluates functional adaptation in ALS patients with lower motor neuron predominant (LMNp) and upper motor neuron predominant (UMNp) dysfunction. Methods: Seventeen LMNp ALS patients, 14 UMNp ALS patients and 14 controls participated in a functional magnetic resonance imaging study. Studygroup-specific activation patterns were evaluated during preparation for a motor task. Connectivity analyses were carried out using the supplementary motor area (SMA), cerebellum and striatum as seed regions and correlations were explored with clinical measures. Results: Increased cerebellar, decreased dorsolateral prefrontal cortex and decreased SMA activation were detected in UMNp patients compared to controls. Increased cerebellar activation was also detected in UMNp patients compared to LMNp patients. UMNp patients exhibit increased effective connectivity between the cerebellum and caudate, and decreased connectivity between the SMA and caudate and between the SMA and cerebellum when performing self-initiated movement. In UMNp patients, a positive correlation was detected between clinical variables and striato-cerebellar connectivity. Conclusions: Our findings indicate that, despite the dysfunction of SMAstriatal and SMA-cerebellar networks, cerebello-striatal connectivity increases in ALS indicative of compensatory processes. The coexistence of circuits with decreased and increased connectivity suggests concomitant neurodegenerative and adaptive changes in ALS

Extrapyramidal deficits in ALS: a combined biomechanical and neuroimaging study

International audienceIntroduction Extrapyramidal deficits are poorly characterised in amyotrophic lateral sclerosis (ALS) despite their contribu-tion to functional disability, increased fall risk and their quality-of-life implications. Given the concomitant pyramidal and cerebellar degeneration in ALS, the clinical assessment of extrapyramidal features is particularly challenging.Objective The comprehensive characterisation of postural instability in ALS using standardised clinical assessments, gait analyses and computational neuroimaging tools in a prospective study design.Methods Parameters of gait initiation in the anticipatory postural adjustment phase (APA) and execution phase (EP) were evaluated in ALS patients with and without postural instability and healthy controls. Clinical and gait analysis parameters were interpreted in the context of brain imaging findings.Results ALS patients with postural instability exhibit impaired gait initiation with an altered APA phase, poor dynamic postural control and significantly decreased braking index. Consistent with their clinical profile, “unsteady” ALS patients have reduced caudate and brain stem volumes compared to “steady” ALS patients.Interpretation Our findings highlight that the ALS functional rating scale (ALSFRS-r) does not account for extrapyramidal deficits, which are major contributors to gait impairment in a subset of ALS patients. Basal ganglia degeneration in ALS does not only contribute to cognitive and behavioural deficits, but also adds to the heterogeneity of motor disabilit