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Summary In the present work we evaluate the accumulation and further remobilization of vegetative storage proteins (VSP) in chicory. A protein with molecular weight of 17kDa, corresponding to 7 isoforms with pi ranging between 5 and 7, accumulated dramatically over the vegetative phase from spring to autumn and was extensively depleted during the flowering period in the following summer, a pattern typical for a VSP. When mature tuberized roots of chicory are harvested in autumn and forced in darkness, an etiolated bud (chicon) grows: this is the salad known as Belgian endive. In our experiments plants were fed, during the forcing process, nutrient solutions containing 1.5 or 18 mmol/L 15 NO 3 (1.79 % atom excess 15 N) or with demineralized water (control). We determined the cycling of endogenous nitrogen ( 14 N), protein (VSP) and amino acids, and the movement of concurrently absorbed nitrogen ( 15 N). Soluble proteins were remobilized at the onset of forcing as a primary response of nitrogen cycling in chicory root. Amino acid remobilization took place only when the chicon growth began with arginine remobilized first. Although 14 N flux into the chicon was similar in all three treatments, indicating that NO 3 supply did not effect endogenous N remobilization, VSP use was effected by NO 3 supply. SDS-PAGE and 2-D gel electrophoresis analyses showed an extensive depletion of VSP (especially five isoforms) only in the control. We suggested that extensive and specific depletion of VSP was delayed by NO 3 supply; with higher NO 3 availability, there was lower VSP remobilization. Furthermore, neo-synthesis of VSP could occur during the forcing process. The finding that 15 N was incorporated into the protein pool during this period supports this hypothesis. The chicon constituted a very strong sink for absorbed nitrogen. Either in high or low NO 3 supply, 15 N was translocated to the chicon almost without mixing with the bulk nitrogen of the root.

Temporal speech cues, such as periodicity and voice onset time (VOT), are particularly salient information for speech intelligibility. In addition, speech elicited auditory brainstem response (Speech ABR) to consonant vowels (CV) has been shown to mimic the temporal periodicity of the acoustic signal very accurately. Consequently, Speech ABR has been described as a potential objective tool to explore the temporal integration of speech excerpts in human brainstem. We aimed at putting in evidence the specialization of temporal encoding of speech vs nonspeech signals through clinical and behavioral measurements. A sum of five sinusoids, at the five formant frequencies, modulated by the corresponding CV temporal envelope, was taken as speech‐analogue. Accordingly, Speech and Analogue ABRs components were compared, although a priori due to be similar. Furthermore, categorical perception assessment was processed to both analogue and full‐speech continuums. If confirmed, these preliminary results (seven normal hearing adults for physiological ABRs and behavioral categorical perception) would bring further evidence of an early specialization of temporal processing of speech, in line with previous research [Kraus and Nicol, Trends in Neuroscience 28(4), 176‐‐81 (2005)]. [Work supported by CNRS, Cochlear & Univ.Lyon 1.]

Summary Objectives The authors analyse the predictive diagnostic accuracy of fine-needle aspiration cytology (FNAC) and frozen section examination in adult patients operated for thyroid nodules. Patients and methods The same pathologist performed macroscopic and cytological examination, followed by frozen section examination on each operative specimen. FNAC results were classified into three groups: benign, malignant or suspicious of malignancy. Frozen section examination was also classified into three categories: benign, malignant or suspicious of malignancy when not all criteria of malignancy were present. Results One hundred and sixty-six (82%) of the 202 patients included in the study were females. Patients had a mean age of 51 years. Thyroid carcinoma was diagnosed on final pathology in 22% of women and 25% of men. FNAC results were benign in 85% of cases, malignant in 9% of cases and atypical or suspicious in 6% of cases, with a specificity of more than 99% and a sensitivity, including and excluding microcarcinomas, of 36% and 48%, respectively. The diagnostic accuracy of FNAC was 84% and 89%, after excluding micro-carcinomas. Frozen section was benign in 85% of cases, malignant in 13% of cases and suspicious in 2% of cases, with a specificity of more than 99% and a sensitivity, including and excluding microcarcinomas, of 56% and 68%, respectively. The diagnostic accuracy of frozen section was 89% and 90%, after excluding microcarcinomas. The diagnostic accuracy of the combination of the two examinations was 94% after excluding microcarcinomas. Conclusion FNAC and frozen section have a comparable predictive diagnostic accuracy. Frozen section is requested by the surgeon not only on the basis of preoperative FNAC, especially when it is suspicious, or even indeterminate, but also in the light of the macroscopic surgical findings.

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Comment la diversité fonctionnelle des vers de terre modifie les interactions entre plantes dans un couvert associé ?. TEBIS V, Traits écologiques et biologiques des invertébrés du sol

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http://dx.doi.org/10.1111/j.1399-3054.2004.00366.x; International audience

SummaryTympanoplasty now frequently uses cartilage to repair bone lysis in the external auditory canal (EAC) and to reinforce the tympanic membrane. Once in place, however, the cartilage may complicate ossiculoplasty by obstructing visualization of the stapedial region. Posterior tympanotomy, when included in the tympanoplasty procedure, may provide an interesting means of positioning the ossiculoplasty.

There is a growing and unprecedented interest in the objective evaluation of the subcortical processes that are involved in speech perception, with potential clinical applications in speech and language impairments. Here, we review the studies illustrating the development of electrophysiological methods for assessing speech encoding in the human brainstem: from the pioneer recordings of click-evoked auditory brainstem responses (ABR), via studies of frequency-following responses (FFR) to the most recent measurements of speech ABR (SABR) or ABR in response to speech sounds. Recent research on SABR has provided new insights in the understanding of subcortical auditory processing mechanisms. The SABR test is an objective and non-invasive tool for assessing individual capacity of speech encoding in the brainstem. SABR characteristics are potentially useful both as a diagnosis tool of speech encoding deficits and as an assessment tool of the efficacy of rehabilitation programs in patients with learning and/or auditory processing disorders.

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SummaryObjectivesTo report the results obtained in patients with intact tympanic membrane tympanosclerotic stapes fixation treated by labyrinthine fenestration and to discuss the value of this operation.Materials and methodsRetrospective study of 28 cases of tympanosclerotic stapes fixation operated between 1982 and 2010. Labyrinthine fenestration was performed using a CO2 laser. In the first group of patients, the columellar effect was restored by stapedectomy with graft interposition and reconstruction was performed by TORP prosthesis and in the second group, stapedotomy was performed with reconstruction by a piston crimped onto the long process of incus (LPI) or the malleus handle (MH).ResultsPostoperatively (2 to 6months), stapedectomy and reconstruction by TORP prosthesis allowed a gain of the mean Rinne by 18dB and reconstruction by piston crimped onto the LPI or an MH placed in the stapedotomy orifice allowed a gain of 14dB. With a follow-up of 3years, this gain was maintained with the first technique. No case of cophosis or sensorineural hearing loss greater than 20dB was observed.ConclusionLabyrinthine fenestration provides an immediate hearing gain in patients with tympanosclerotic stapes fixation with the two techniques used. In the longer term, these good results were maintained with the stapedectomy and TORP prosthesis technique, but the hearing gain was no longer statistically significant in the long-term with the stapedotomy technique because of a limited number of cases. However, only a study based on a larger number of patients would be able to confirm the superiority of TORP compared to stapedotomy. Labyrinthine fenestration, which comprised only a low risk of deterioration of hearing and which did not induce any total hearing loss, must nevertheless be performed only in the case of severe bilateral conductive hearing loss, with an intact tympanic membrane, in patients refusing a hearing aid and informed about the risks of deterioration of hearing.

* INRA Métabolisme et Nutrition des Plantes, centre de Versailles Diffusion du document : INRA Métabolisme et Nutrition des Plantes, centre de Versailles Diplôme : DEA

Improving rapeseed yields in a low-Nitrogen (N) agricultural context is a major issue for breeding. It requires a thorough knowledge of the genotypic variation of the processes related to Nitrogen Use Efficiency (NUE, seed yield per unit of N available). This PhD aims at better understanding the ecophysiological processes determining the NUE and its components under low-N availability by identifying and hierarchizing the main traits supporting observed genotypic variation. Six winter oilseed rape genotypes were investigated throughout the crop cycle under semi-controlled conditions and contrasting N-conditions. We proposed NUE_DM (plant dry matter per unit of N available), as a new proxy of NUE at harvest, valid as early as the beginning of stem elongation. This proxy allowed us to dynamically characterize NUE, highlighting NUpE (plant N-amount per unit of N available) as a main contributor of NUE under low-N conditions, which explained up to 80% of the NUE_DM variations before flowering, and more than 30% after. Moreover, NUpE genotypic variability resulted from fine root growth rather than specific N-uptake differences. We developed a whole-plant conceptual modeling framework of carbon and nitrogen absorption and partitioning for winter oilseed rape. This framework, validated up to flowering, highlighted specific carbon assimilation, carbon partitioning between leaves and stems, and fine root ratio as critical traits explaining contrasting genotypic behavior to N-conditions. Our results suggest NUpE and fine root ratio as promising traits for screening larger sets of varieties for NUE breeding purposes., Améliorer le rendement du colza dans un contexte de bas intrants azotés (N) est un enjeu majeur de sélection. Ceci impose une connaissance approfondie de la variabilité génétique des processus sous-tendant l’efficacité d’utilisation de l’azote (NUE, rendement en graines par unité d’azote disponible). Cette thèse vise à mieux comprendre les processus écophysiologiques contribuant à la NUE et à ses composantes sous faible nutrition azotée, en identifiant et hiérarchisant les principaux traits sous-tendant leur variabilité génotypique. Six génotypes de colza d’hiver ont été étudiés en conditions semi-contrôlées sous des doses d’azote contrastées. Nous avons montré que la variable NUE_DM (biomasse totale produite par unité d’azote disponible) est un indicateur précoce de la NUE à la récolte valable dès la montaison, qui nous a permis de caractériser dynamiquement la NUE. L’efficience d'absorption d’azote (NUpE, N absorbé par unité d’azote disponible) s’est révélée être une composante majeure de la NUE sous contrainte azotée, expliquant 80 % des variations avant la floraison, et plus de 30 % après. De plus, sa variabilité génotypique dépend de la biomasse des racines fines et non de l’absorption spécifique d'azote. Grâce au développement d’un cadre conceptuel de modélisation du fonctionnement du colza décrivant les flux de carbone et d’azote dans la plante entière et valable jusqu’à floraison, nous avons fait ressortir l'assimilation spécifique de carbone, la part de carbone allouée aux tiges et la proportion de racines fines comme paramètres clés de la réponse génotypique à l’azote. Nos résultats suggèrent que la NUpE et la proportion de racines fines seraient des indicateurs de la NUE permettant de cribler précocement des variétés à haut débit.