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Peri-insular hemispherotomy is a surgical technique used in the treatment of drug-resistant epilepsy of hemispheric origin. It is based on the exposure of insula and semi-circular sulci, providing access to the lateral ventricle through a supra- and infra-insular window. From inside the ventricle, a parasagittal callosotomy is performed. The basal and medial portion of the frontal lobe is isolated. Projections to the anterior commissure are interrupted at the time of amygdala resection. The hippocampal tail and fimbria-fornix are disrupted posteriorly. We report our experience of 18 cases treated with this approach. More than half of them presented with congenital epilepsy. Neuronavigation was useful in precisely determining the center and extent of the craniotomy, as well as the direction of tractotomies and callosotomy, allowing minimal exposure and blood loss. Intra-operative monitoring by scalp EEG on the contralateral hemisphere was used to follow the progression of the number of interictal spikes during the disconnection procedure. Approximately 90% of patients were in Engel's Class I. We observed one case who presented with transient postoperative neurological deterioration probably due to CSF overdrainage and documented one case of incomplete disconnection in a patient presenting with hemimegalencephaly who needed a second operation. We observed a good correlation between a significant decrease in the number of spikes at the end of the procedure and seizure outcome. Peri-insular hemispherotomy provides a functional disconnection of the hemisphere with minimal resection of cerebral tissue. It is an efficient technique with a low complication rate. Intra-operative EEG monitoring might be used as a predictive factor of completeness of the disconnection and consequently, seizure outcome.

Rough skin or xerosis, known by the laity as dry skin, results from a defect in the stratum corneum desquamation which normally remains imperceptible. This condition is negatively influenced by winter climatic conditions. Atopic dermatitis and trophic changes related to post-menopause, ageing, diabetes mellitus, as well as other endrocrine and metabolic disturbances are also involved in this process. Xerosis can be improved at various degrees by emollients, humectants, hydrating agents and squamolytic agents.

Event-related potentials (ERPs) studies in human subjects have shown inter-individual response variations, probably linked to anatomical and functional brain disparities. The present study was conducted to compare the results obtained by a standard grand-average method and a single subject analysis of VEPs to faces.Fifty-eight channel ERPs (analysis time: 1,024 ms) were recorded in 13 normal volunteers during gender or familiarity judgements on unknown and known faces, as well as on a control task using meaningless patterns. Data were then submitted to individual and group averages.Three activities were identified by both procedures: a P1/N1 complex, a vertex positive potential (P2 or VPP) associated with a temporal negativity, and a N2 negativity. These peaks displayed a marked inter-individual topographical variability. Regarding the outcome of statistical analyses, a certain number of differences were found: on P1, in which individual analyses revealed a strong effect of experimental conditions, while the grand-average method did not; on VPP, in which grand-average analyses suggested an interaction between experimental conditions, face familiarity and cerebral lateralization, while individual analyses did not; and on N2, in which grand-average data showed a clear lateralization effect, while individual analyses did not. A P3 component (Pz, 250 ms) was also defined in grand-average data, but could not be clearly described in individual data. Statistical analyses on this P3 component were thus only performed on group data and revealed a right lateralization and an interaction between face familiarity and experimental conditions. These findings confirmed the existence of a marked topographical variability of ERPs to face and, therefore, question the validity of grand-average studies. Moreover, these results suggest a better efficiency of individual analyses for studying short and middle-latency peaks, while grand-averages appear to be better suited for studying late components.

International audience; We studied the early stages of gene amplification in a Chinese hamster cell line and we show that two distinct mechanisms can operate at a single locus. Both of them rely on an unequal segregation of gene copies at mitosis. We conclude that cycles of chromatid breakage, followed by fusion of sister chromatids devoid of a telomere that lead to further breaks in mitosis, have a key role in the coupling of gene amplification and genome remodeling. Rearrangements are first limited to a single chromosome but can then potentially spread to any additional chromosome. Occasionally, a sequence containing the selected gene can be looped out, generating a "double minute" and thus initiating an independent process of extrachromosomal amplification.

Lower-limb somatosensory evoked potentials (SEPs) of nerve-trunk (peroneal nerve, posterior tibial nerve) and dermatomal (L5 and S1) stimulation were recorded in 120 patients suffering from lumbosacral disk disease. Recordings were performed before surgery and on Days 4 and 50 after surgery. Electromyography was also performed before surgery. Dermatomal SEPs were shown to be sensitive (70%) and specific in both terms of their lateralizing value and their ability to identify the L5 or S1 level. Moreover, combining SEPs and EMG significantly increased the sensitivity of the electrophysiological testing when compared with each method alone. There was no relationship between SEPs performed before surgery and surgical outcome. Inversely, we demonstrated the prognostic value of SEPs performed on Day 4, SEP normalization at Day 4 was associated with a good outcome at Day 50 in 91.8% of examined cases, while the persistence of pathological SEPs at Day 4 was associated with poor outcome at Day 50 in 56% of the cases.

Over the past few years, the criteria defining the sleep apnea syndrome have been well delineated. This syndrome is a common affliction whose pathophysiology is usually indicative of an obstacle in the upper respiratory tract. The authors describe seven mostly serious cases, with cardiovascular and hemodynamic repercussions, that benefited from ORL surgery (uvulo-palato-pharyngoplasty and/or tonsillotomy). In each case, the consequences of this simple surgery were excellent, resulting in a sharp attenuation of the symptoms or their disappearance. In conclusion, the authors insist on the preponderant role that can be played by the ear, nose and throat specialist, both in the selection of these patients and in their treatment.

Polygraphic sleep recordings were performed in two patients with nocturnal myoclonus. The beneficial effect of Clonazepam has been confirmed in the two cases.

The intervention policy on the EEC grain market is completed by a system of monthly increments designed to level the sales of grain all over the year. The efficiency of this organisation is compared with the price formation over time on futures markets., La stabilisation des marchés agricoles européens par une politique de stockage d'intervention et de restitution à l'exportation est complétée par le système des majorations mensuelles qui vise à répartir les livraisons sur la campagne toute entière. L'efficience de cette technique doit être comparée à celle qui ressort de l'équilibrage dans le temps de l'offre et de la demande de produits agricoles résultant du différentiel de prix entre marchés au comptant et marchés à terme., Debatisse Michel-Louis. Allocation dans le temps des produits agricoles: comparaison entre le système des majorations mensuelles communautaire et celui de la mise à prix de l'espace de stockage sur les marchés à terme. In: Économie rurale. N°142, 1981. p. 29.

National audience

In metazoan cells, inactivation or depletion of DDR factors, such as ATR, BRCA2, Chk1, Claspin, Rad51 or Wee1, leads to replication fork slowing and increased initiation density. Until now the mechanism by which these deficiencies modulate the replication dynamics has remained unclear, although a specific model has been proposed in the case of Chk1. However, the similarity in the phenotype observed in different DDR-deficient cells suggests to us that a common mechanism modulates the replication dynamics in all cases. We reasoned that a feature common to all DDR-deficient cells is that they are prone to accumulate DNA damages. On the other hand, DNA damages impact dNTPs biosynthesis in various organisms, which prompted us to determine whether the switch in replication dynamics observed in Chk1- and Rad51-deficient cells relies on damage signaling. Our results reconstitute, in two cell types, a signaling pathway that modulates the replication dynamics when DNA damage is present in S phase: DNA lesions ___>ATM/Chk2 ___> p53 ___> accumulation and chromatin recruitment of the repair-specific subunit of the ribonucleotide reductase (p53R2) ___> decreased availability of dNTPs for the replication machinery ___> replication fork slowing ___> passive activation of latent origins., Au cours de ma thèse au sein du laboratoire du Professeur Michelle Debatisse, je me suis intéressé aux mécanismes maintenant la stabilité du génome et contrôlant la dynamique de réplication dans les cellules de mammifères. J'ai étudié le rôle des kinases ATR (" Ataxia Telangectasia and Rad3 related ") et Chk1 (" Checkpoint Kinase 1 "), du point de contrôle intra-S (" checkpoint "), dans le contrôle de la dynamique de réplication. Cette première étude m'a amené à étudier la relation entre les dommages à l'ADN et la dynamique de réplication, dans des modèles cellulaires déficients pour des facteurs de la réponse aux dommages à l'ADN (DDR), appartenant soit au " checkpoint ", soit à la voie de réparation par recombinaison homologue (HR), tels que Rad51 et BRCA2. Je montre ici, que le ralentissement des fourches de réplication et l'augmentation de la densité d'événements d'initiation, observés dans des cellules déficientes pour Chk1 ou Rad51, sont la conséquence indirecte des lésions apparaissant spontanément dans de telles cellules. Le ralentissement des fourches dans ces cellules dépend d'une perturbation de la disponibilité en précurseurs de nucléotides qui dépend de la sur-expression et/ou de la re-localisation de la sous-unité p53R2 de la ribonucléotide réductase (RNR). De plus, contrairement à ce qui était proposé, je montre que Chk1 n'a pas de rôle actif dans la répression des origines latentes, mais que c'est la vitesse des fourches qui détermine l'espacement entre les origines actives, par un mécanisme de compensation découvert auparavant au laboratoire (Anglana, 2003 ; Courbet, 2008). L'ensemble de mes résultats permet de proposer un mécanisme général de communication entre la réplication et la réparation. Ce mécanisme confère un avantage aux cellules, puisque le ralentissement des fourches stabilise la machinerie de réplication qui voyage sur une matrice endommagée, et l'activation d'origines latentes procure une source de sauvetage pour les fourches bloquées.