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La petite production d’ananas emerge en Cote-d’Ivoire dans les annees soixante, comme culture destinee a la conserverie, et disparait sous cette forme au debut des annees 1980. Elle re-emerge a la meme epoque, mais destinee a l’exportation de fruits frais, avant de s’effondrer a nouveau au milieu des annees 2000. Une premiere partie de l’article presente les dispositifs organisationnels et institutionnels qui ont permis l’essor d’une culture d’exportation non traditionnelle aussi intensive en travail et en intrants chez les petits producteurs : agriculture contractuelle a l’epoque « ananas de conserve », jeu de relations contractuelles multiplexes avec l’amont et l’aval de la production, a l’epoque « ananas pour l’exportation en frais ». Une seconde partie identifie les acteurs de cette production : essentiellement des petits planteurs burkinabe accedant a la terre par un contrat de location. La derniere partie questionne la durabilite de cette production a travers l’analyse de la crise de la production pour la conserverie, puis de l’effondrement de la production de fruits frais pour l’exportation.

IntroductionAtypical and malignant meningiomas are a rare disease whose histological definition is still recent. Their management is not consensual. The aim of this study was to review the outcome, prognostic factors and the role of complementary therapies.Patients and methodsBetween 1999 and 2007, 36 patients with atypical or malignant meningiomas were managed in our hospital. All surgical specimens were reviewed according to the 2007 WHO classification system. The sex ratio was 1.25 male, the median age was 59 years. The median follow-up was 55 months. Thirty meningiomas were atypical and six were malignant.ResultsFive and 10 years overall survival rate are respectively 72 and 41%, whereas 5 and 10 years progression free survival rate are 61 and 23%. We only identify female sex, age over 70 years and Karnofsky status under 70% as negative prognostic factors.ConclusionAtypical and malignant meningiomas are difficult to manage and have high recurrence and poor survival rates. The prognostic of OMS II meningiomas is heterogeneous. Adjuvant radiation therapy is recommended in case of malignant menigioma or in case of atypical meningioma if incomplete surgical excision is performed.RésuméIntroductionLes méningiomes atypiques et malins sont une pathologie rare dont la définition histologique est encore récente. Leur prise en charge n’est pas consensuelle. Le but de notre étude est d’analyser le devenir, les facteurs pronostiques et le rôle des traitements complémentaires.Patients et méthodesL’étude a été menée de façon rétrospective au sujet de 36 patients présentant un méningiome atypique ou anaplasique pris en charge consécutivement entre 1999 et 2007 dans le service de neurochirurgie de Reims. Le diagnostic histologique a été établi selon les critères de la classification OMS de 2007. Le sex-ratio est 1,25 (H/F) et l’âge moyen 59ans. Sur les 36 méningiomes étudiés, 30 sont atypiques (OMS II) et six sont malins (OMS III). Le suivi médian est de 55 mois.RésultatsPour l’ensemble de la série, les taux de survie globale à cinq et dix ans sont respectivement de 72 et 41 %. Les taux de survie sans récidive à cinq et dix ans sont de 61 et 23 %. En analyse univariée, ces taux de survie sont influencés péjorativement par le sexe féminin, un âge supérieur à 70ans et un index de performance de Karnofsky inférieur à 70.ConclusionCette étude rétrospective monocentrique confirme le fort potentiel récidivant et le pronostic péjoratif des méningiomes atypiques et anaplasiques. Elle retrouve une hétérogénéité de pronostic au sein des méningiomes de grade OMS II.

Cutaneous adverse events induced by epidermal growth factor receptor (EGFR) inhibitors can hamper the patients' quality of life. The aim of our work was to draft an algorithm for the optimised management of this skin toxicity.This algorithm was built in three steps under the responsibility of a steering committee. Step I: a systematic literature analysis (SLA) has been performed. Step II: the collection of information about practices was performed through a questionnaire.These questions were asked during regional meetings to which oncologists, gastro-enterologists, radiotherapists, and dermatologists were invited. Step III: a final meeting was organised involving the bibliography group and the steering committee and regional scientific committees for proposing a final algorithm.Step I: 14 publications were selected to evaluate the use of cyclines as curative or prophylactic treatment of the folliculitis induced by EGFR inhibitors. Nineteen publications were retained for the topical treatment of the folliculitis. Forty-six articles were selected for the management of the cutaneous lesions in link with appendages and 12 for xerosis and pruritus. Step II: 96 delegates attended the seven regional meetings and 67 questionnaires were analysed. Step III: a final algorithm was proposed on the basis of the conclusions of the first two steps and expert opinions present at this final meeting. The different propositions were unanimously approved by the 14 experts who voted.This multidisciplinary study summarising published data and current practices produced a therapeutic algorithm, which should facilitate the standardised, optimised management of skin toxicity associated with EGFR inhibitors in France.

Cet article presente une etude exploratoire des conditions d’enseignement-apprentissage de l’effet de serre naturel en seconde. La construction d’un parcours d’enseignement-apprentissage repose sur une prise en compte imbriquee d’une analyse de contenu de la physique mise en jeu et du reperage des difficultes des eleves. Ce reperage est effectue a partir d’entretiens prenant appui sur un modele materiel de l’effet de serre et sur des schemas de vulgarisation. Les principaux obstacles a la comprehension de l’effet de serre naturel chez les eleves interroges resident dans l’absence de prise en compte du phenomene d’absorption-emission infrarouge et dans la frequente mise en œuvre de raisonnements a caractere sequentiel. La mise en exergue du phenomene d’absorption-emission infrarouge tout au long du parcours s’avere donc necessaire. Le couplage entre temperature de surface, types de rayonnements emis et absorbes et echanges energetiques, ainsi que la distinction entre regimes transitoire et permanent, constituent les points cruciaux d’une premiere etape qui s’appuie sur l’exemple d’une planete sans atmosphere. Ce n’est qu’apres cette etape que seront introduits successivement effet de serre naturel avec elaboration de bilans equilibres et rechauffement climatique a l’aide d’un modele materiel.

This article aims to provide some elements relating to the boundaries of education, scientific popularization and research in didactics. This study focuses on greenhouse effect through the resources available on the internet and in textbooks. The students’difficulties relating to the understanding of greenhouse effect already identified permits the building of an images’ typology. In particular, «sequential reasoning» is a very resistant obstacle to combine the evolution of physical quantities during a transitory phase, i. e. an increase of temperature, and the instantaneity of the energy budgets. For both types of documents, our results highlight a wide spectrum of presentations, a strong presence of «echo explanations» and various strategies to bypass the aforegoing difficulties., Cet article vise à apporter quelques éléments relatifs à la délimitation des champs de l’enseignement, de la vulgarisation scientifique et de la recherche en didactique. Cette étude porte sur le thème de l’effet de serre au travers des ressources disponibles en ligne et de manuels scolaires, en accordant une attention particulière aux images présentées. Une typologie des images a été construite à partir des difficultés déjà repérées chez les élèves. La mise en oeuvre très fréquente d’un raisonnement de type séquentiel par les élèves ne leur permet que très difficilement d’allier évolution d’un phénomène, ici une hausse de température, et instantanéité des bilans, ici énergétiques. Nos résultats soulignent, pour les deux types de documents exploités, une grande largeur du spectre des présentations, une forte présence des «explications-écho» ainsi que diverses stratégies de «contournement» des difficultés., Colin Philippe. Enseignement et vulgarisation scientifique : une frontière en cours d’effacement ? Une étude de cas autour de l’effet de serre. In: Spirale. Revue de recherches en éducation, n°48, 2011. Transmettre les sciences : vulgarisation et enseignement, sous la direction de Johann-Günther Egginger. pp. 63-84.

Background: This prospective multicentric phase II study aimed to confirm the results of the C5R protocol of high-dose methotrexate (MTX)-based chemotherapy (CT) for immunocompetent primary central nervous system lymphoma. Patients and methods: A total of 99 patients received age-adapted CT (C5R protocol) followed by radiotherapy. Patients younger than 61 years (group 1, n = 45) received the full C5R with MTX, doxorubicin, vincristine, cyclophosphamide, and cytarabine. Patients aged 61-70 years (group 2, n = 36) received reduced doses. Patients older than 70 years (group 3, n = 18) received four courses of MTX, cyclophosphamide, and etoposide. Results: Median age was 63 years and 51% of patients had performance status of more than one. Seventeen patients died of toxicity during CT. Complete response was achieved in 56%, 53%, and 28% of patients in groups 1, 2, and 3, respectively. With a median follow-up of 83 months, the 5-year progression-free survival was 31%, 28%, and 11% and the 5-year overall survival 42%, 31%, and 17% for groups 1, 2, and 3, respectively. Leukoencephalopathy occurred in 32% of assessable patients, in both group 1 and groups 2-3. Conclusion: The C5R protocol was feasible in the multicentric setting with favorable long-term survival in patients younger than 60 years. Despite dose adaptation, results in older patients were disappointing.

Resume Les meningiomes de la gaine du nerf optique representent un tiers des tumeurs du nerf optique, 1 a 2 % des meningiomes et enfin 2 a 3,5 % des tumeurs orbitaires. La baisse de l’acuite visuelle domine le tableau clinique. Le diagnostic est facilement evoque apres realisation du bilan neuroradiologique. Le traitement consacre est depuis peu la radiotherapie fractionnee en conditions stereotaxiques (RSF). Elle permet de facon optimale le respect de l’acuite visuelle et le controle du volume tumoral.

Land is of fundamental concern in economic and political development. In African contexts discussion of land is commonly framed by questions of how customary land tenure systems are moving towards private property models involving land markets. Empirical studies remain sparse, but the evidence suggests that, while land markets are becoming more common, disputes over the meaning of transactions are also increasing. Most published work tends to concentrate on market development rather than exploring the social relationships embodied in land markets, and their political consequences. This Special Issue, comprising an extensive introduction by the guest editors and a further six papers covering studies on Ghana, Cote d'Ivoire, Zimbabwe and Zambia, seeks to address these gaps. Themes and questions addressed include the role of the state in the reform of customary land rights. Despite trends towards private property, around ninety percent of land in Africa is still considered to be under customary land tenure. Thus the majority of land market transactions are 'informal', the meaning of transactions is disputed, and there is widespread insecurity over the transferred land rights. Land markets are also implicated in key questions relating to discourses of fairness or justice of land access, and the linkage of land rights to autochthony, ethnicity and citizenship. The broader significance of the papers is to contribute to a more critical analysis of institutional change. They mark a step forward in African land policy debates that largely remain polarized between those seeking poverty reduction through promoting land markets, and opponents who seek to protect the poor from losing their land to the market. Of perhaps most far-reaching significance, the papers suggest that an understanding of actually-existing land markets is central to the analysis of the roots of conflict and insecurity in Africa today.

International audience; The article offers an empirical perspective regarding customary land sales in Côte d'Ivoire, focusing on their socio-political embeddedness as well as on the implications of such processes for the content of the rights and duties transferred. Two interlinked aspects of land transfers, which usually come together in African contexts, are to be taken into account: rights and obligations regarding land access and control ('the land resource dimension'), and rights and obligations regarding group membership, and more generally the socio-political dimensions that condition the social recognition and effectiveness of the transfer of land rights ('the socio-political dimension'). These two dimensions are empirically explored, together with the processes of their connection and possible disconnection/reconnection. We show that the diverging interpretations of land transfers, from emic as well as from etic viewpoints, do not necessarily correspond to mutually exclusive explanatory models, or to a simple transition phase from customary to 'pure' market land transfers. Access to land may become commoditized without extinguishing the socio-political dimension of land transactions. Another point is that the articulation of these two dimensions of land transfers is a specific and always contextualized issue. This has direct consequences on the legitimacy of land transfers as well as on the security of the stranger right holder within the local community and more generally on the politicization of land issue.; L'article offre une perspective empirique des ventes de terres coutumières en Côte d'Ivoire, en s'intéressant à leur enchâssement sociopolitique et aux implications de tels processus pour le contenu des droits et des obligations transférés. Il prend en compte deux aspects interconnectés des transferts de terres, généralement réunis dans des contextes africains : d'une part les droits et les obligations impliqués dans l'accès à la terre et son contrôle (« la dimension ressource foncière »), et d'autre part les droits et les obligations impliqués dans l'appartenance à un groupe, et plus généralement les dimensions sociopolitiques qui conditionnent la reconnaissance sociale et le caractère effectif du transfert des droits fonciers («la dimension sociopolitique»). L'article explore ces deux dimensions de manière empirique, ainsi que les processus afférents à leur connexion et leur déconnexion/reconnexion possible. Il montre que les interprétations divergentes des transferts de terres, tant du point de vue émique que du point de vue étique, ne correspondent pas nécessairement à des modèles explicatifs mutuellement exclusifs, ni à une simple phase de transition d'un transfert coutumier à un transfert de marché « pur ». Une marchandisation de l'accès à la terre peut survenir sans effacer la dimension sociopolitique des transactions foncières. D'autre part, l'articulation de ces deux dimensions du transfert de terres est un sujet spécifique qui s'inscrit toujours dans un contexte. Il en découle des conséquences directes sur la légitimité des transferts de terres, ainsi que sur la sécurité du titulaire de droit étranger au sein de la communauté locale et, plus généralement, sur la politisation de la question foncière.

Purpose This study compared chemotherapy discontinuation with maintenance therapy with leucovorin and fluorouracil after six cycles of folinic acid, fluorouracil, and oxaliplatin (FOLFOX) chemotherapy in the first-line treatment of metastatic colorectal cancer. Patients and Methods Two hundred two patients with untreated metastatic colorectal cancer were randomly assigned to receive six cycles of modified FOLFOX7 (mFOLFOX7) followed by simplified leucovorin plus bolus and infusional fluorouracil until progression (arm 1 or maintenance arm, n = 98) or six cycles of mFOLFOX7 before a complete stop of chemotherapy (arm 2 or chemotherapy-free interval [CFI] arm, n = 104). Reintroduction of mFOLFOX7 was scheduled after tumor progression in both arms. The primary study end point was duration of disease control (DDC). Results Median DDC was 13.1 months in patients assigned to the maintenance arm and 9.2 months in patients assigned to the CFI arm (P = .046). Median progression-free survival (PFS) and overall survival were 8.6 and 23.8 months, respectively, in the maintenance arm and 6.6 and 19.5 months, respectively, in the CFI arm. Median duration of maintenance therapy (arm 1) and CFIs (arm 2) were 4.8 months and 3.9 months, respectively. Overall response rates were 59.2% and 59.6% for the initial FOLFOX chemotherapy and 20.4% and 30.3% for FOLFOX reintroduction in arms 1 and 2, respectively. Conclusion The planned complete discontinuation of chemotherapy had a negative impact on DDC and PFS compared with the maintenance therapy strategy. These results suggest that chemotherapy discontinuation cannot be decided before therapy is initiated in patients with advanced colorectal cancer.

[Departement_IRSTEA]GT [TR1_IRSTEA]RURAMEN / AMANDE; Following the implementation of the land reform in the 1990's, land rentals have developed in Romania, mainly in a reverse tenancy configuration. The paper provides an analysis of contractual practices in this configuration, based on empirical data collected through intensive field work in Transylvania. The paper depicts the reverse tenancy configuration and the conditions of its emergence in Romania, following the implementation of transition reforms in the agricultural sector. Characterizing the negotiation and enforcement of contracts in this configuration shows that in a situation where no effective enforcement mechanism is available, the market structure is such that tenants can choose very incomplete contracts or default on their contractual obligations. The analysis of the landowners' perspective, taking into account their perception of the contractual relationship contributes to explain why contractual practices persist in this context. The article concludes with a discussion, from a policy perspective, of the equity-enhancing role of the land lease market in such this reverse tenancy configuration.

Optic nerve sheath meningioma (ONSM) accounts for one-third of primary optic nerve tumors, and 2% of all meningiomas. ONSM must be distinguished from other meningiomas, in particular from cavernous meningiomas because of the different prognosis and treatment. The most frequent clinical sign is a progressive or sudden unilateral visual loss. Treatment of ONSM is still subject to discussion. This report covers a series of eight ONSM patients treated with fractionated stereotactic radiotherapy. Material and methods Between 2000 and 2006, we managed eight patients with ONSM. The average patient age was 47 years. There were five women and three men. The most frequent clinical signs were visual loss (100%), proptosis (35%), diplopia (25%). One patient was initially treated with surgery. All patient have been treated by fractionated stereotactic radiotherapy. 45 Gy in 25 fractions were delivered on the meningioma area at a rate of 5 fractions of 1.8 Gy per week. We used a Brainlab ® framework associated with a thermo-formed mask. A computed tomography then magnetic resonance imaging was obtained for each patient. The data was merged and planning took place on a Brainlab ® dosimetric console. The treatment was performed with a head-only Varion linear accelerator, with a Brainlab ® multi-blade collimator. Results The average follow-up was 27 months. Each patient had a complete radiological and ophthalmologic exam every 3 months during the first year, then every 6 months thereafter. Tumor control rate was 100%. Vision was re-established in five patients and three patients had improvement, including one patient during treatment. 100% of proptosis and diplopias regressed. No side effect was reported. Conclusion This is still a preliminary study, but the results suggest that fractionated stereotactic radiotherapy may emerge as a primary treatment for ONSM, delaying surgery, which has proven functionally disappointing.

BACKGROUND: Maraviroc (MVC) is an allosteric CCR5 inhibitor used against HIV-1 infection. While MVC-resistant viruses have been identified in patients, it still remains incompletely known how they adjust their CD4 and CCR5 binding properties to resist MVC inhibition while preserving their replicative capacity. It is thought that they maintain high efficiency of receptor binding. To date however, information about the binding affinities to receptors for inhibitor-resistant HIV-1 remains limited. RESULTS: Here, we show by means of viral envelope (gp120) binding experiments and virus-cell fusion kinetics that a MVC-resistant virus (MVC-Res) that had emerged as a dominant viral quasispecies in a patient displays reduced affinities for CD4 and CCR5 either free or bound to MVC, as compared to its MVC-sensitive counterpart isolated before MVC therapy. An alanine insertion within the GPG motif (G310_P311insA) of the MVC-resistant gp120 V3 loop is responsible for the decreased CCR5 binding affinity, while impaired binding to CD4 is due to sequence changes outside V3. Molecular dynamics simulations of gp120 binding to CCR5 further emphasize that the Ala insertion alters the structure of the V3 tip and weakens interaction with CCR5 ECL2. Paradoxically, infection experiments on cells expressing high levels of CCR5 also showed that Ala allows MVC-Res to use CCR5 efficiently, thereby improving viral fusion and replication efficiencies. Actually, although we found that the V3 loop of MVC-Res is required for high levels of MVC resistance, other regions outside V3 are sufficient to confer a moderate level of resistance. These sequence changes outside V3, however, come with a replication cost, which is compensated for by the Ala insertion in V3. CONCLUSION: These results indicate that changes in the V3 loop of MVC-resistant viruses can augment the efficiency of CCR5-dependent steps of viral entry other than gp120 binding, thereby compensating for their decreased affinity for entry receptors and improving their fusion and replication efficiencies. This study thus sheds light on unsuspected mechanisms whereby MVC-resistant HIV-1 could emerge and grow in treated patients. This work was supported by Agence Nationale de la Recherche sur le SIDA (ANRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Institut Pasteur, Laboratoire d’Excellence “Integrative Biology of Emerging Infectious Diseases” (Grant ANR-10- LABEX-62-IBEID), Instituto de Salud Carlos III (Intrasalud PI12/0056), the Spanish Ministry of Health (EC11-175) and Red de investigación en SIDA RD12/0017/0015 as part of the Plan Nacional R + D + I and cofinanced by ISCIII- Subdirección General de Evaluación and Fondo Europeo de Desarrollo Regional (FEDER). Sí

Les réformes mises en œuvre dans le secteur agricole roumain ont conduit à une décollectivisation massive. On observe cependant le maintien d’associations de production issues des anciennes coopératives, les sociétés agricoles. Sur la base d’enquêtes réalisées en Transylvanie, cet article montre que ces formes associatives reposent sur une allocation de la terre entre un système de Faire-valoir direct (FVD) et un système de Faire-valoir indirect (FVI) et met en évidence l’influence de la dimension organisationnelle sur l’allocation interne et la participation au marché externe du FVI. The reforms implemented in the Romanian agricultural sector have led to massive decollectivization. However, some production associations which where formed from former co-operatives continue to operate. On the basis of surveys conducted in Transylvania, we show that these associations are based on the “intra-organizational” allocation of land between a direct farming-type system and a tenancy-type system. The influence on the organisational aspect of internal land allocation and on participation in the external tenancy market is also brought out in this analysis.

Oxidative stress has been suggested to be an important mediator of dopaminergic cell death in Parkinson's disease (PD). We investigated the neuroprotective potential of Cu/Zn superoxide dismutase (SOD1) overexpression in the rat substantia nigra (SN) following adenovirus-mediated gene transfer. Human dopaminergic SK-N-SH cells were transduced with adenoviral vectors expressing either human SOD1 (Ad-SOD1) or β-galactosidase (Ad-βgal) before exposure to 1 mM of the 1-methyl-4-phenylpyridinium ion (MPP+). A strong neuroprotective effect of SOD1 gene transfer was observed in the SK-N-SH cells exposed to MPP+ compared with controls. Adult rats were then given unilateral injections of either Ad-SOD1 or Ad-βgal into the striatum, and MPP+ was administered 8 days later at the same location. Strong transgene expression was detected in the SN dopaminergic neurons, a consequence of retrograde axonal transport of the adenoviral particles. The amphetamine-induced rotational behavior of the rats was markedly lower in Ad-SOD1-injected rats than in control animals. Also, behavioral recovery significantly correlated with the number of tyrosine hydrolase-expressing neurons in the SN of the treated rats. These results are consistent with oxidative stress contributing to the MPP+-induced neurodegenerative process. They also indicate that SOD1 gene transfer into the nigrostriatal system may be a potential neuroprotective strategy for treating PD. © 2005 Wiley-Liss, Inc.

To optimize and reduce the toxicity of pituitary adenoma irradiation by assessing the feasibility and effectiveness of fractionated stereotactic radiotherapy (FSR).Between 1990 and 1999, 110 consecutive patients, 47 with a functioning adenoma, were treated according to a strategy of either early surgery and FSR (n = 89) or FSR only (n = 21). Of the 110 patients, 75 had persistent macroscopic tumor and 47 persistent hormonal secretions; 15 were treated in the prophylactic setting. The linear accelerator-delivered dose was 50.4 Gy (5 x 1.8 Gy weekly), with a 2-mm safety margin.After a minimal follow-up of 48 months, only 1 patient had developed progression. Of the 110 patients, 27 (36%) had a complete tumor response, 67 (89.3%) had an objective tumor response, 20 (42%) had a hormonal complete response, and 47 (100%) had a hormonal objective tumor response. The proportion of patients without a complete tumor response, objective tumor response, complete hormonal response, and objective hormonal response was 85.1%, 62%, 83%, and 59.3% at 4 years and 49.3%, 9%, 59.3%, and 10.6% at 8 years, respectively. The sole unfavorable predictive factor was preoperative SSE20 mm for tumor response (p = 0.01) and growth hormone adenoma for the hormonal response (p0.001). No late complications, except for pituitary deficiency, were reported, with a probability of requiring hormonal replacement of 28.5% and 35% at 4 and 8 years, respectively. Nonfunctioning status was the sole unfavorable factor (p = 0.0016).Surgery plus FSR is safe and effective. FSR focused to the target volume seems more suitable than standard radiotherapy, and standard fractionation reduces the risk of optic neuropathy sometimes observed after single-dose radiosurgery. Therefore, FSR allows us to consider combined transrhinoseptal surgery and early radiotherapy, with a curative goal without patient selection.

Ce texte propose une contribution a la discussion des conditions d’emergence et de developpement des transactions foncieres en Afrique a partir du cas de la Cote d’Ivoire. La question des marches fonciers est devenue centrale dans la reflexion economique sur le developpement. Les marches de transfert provisoire et definitif de droits sur la terre sont vus comme jouant potentiellement un role determinant dans le processus de developpement, en permettant d’ameliorer l’allocation des facteurs dans un contexte ou les dotations en facteurs de production et en capacites de gestion sont heterogenes. Les effets negatifs, en termes d’equite et/ou d’efficience, que l’on a pu imputer au fonctionnement des marches fonciers (justifiant ainsi des politiques foncieres les prohibant ou les restreignant fortement), sont analyses par l’economie contemporaine du developpement comme resultant plutot de la defaillance de l’environnement de marche (marche du credit, de l’assurance).

Ce texte traite des conditions d’emergence et de transfert des droits sur la terre dans un contexte de veritable micro-frontiere interstitielle, dont la colonisation s’est operee en dehors du rapport autochtones/migrants qui tend a structurer la question fonciere en Cote d’ivoire. L’analyse historique des conditions de la colonisation agricole montre que ce contexte ne renvoie cependant pas a un veritable vide institutionnel, dans la mesure ou des principes partages par les pionniers de differentes origines permirent de reguler l’acces initial a la terre. Par la suite, le caractere de frontiere a facilite les transactions foncieres, dans la mesure ou le droit du pionnier sur la terre ne venait pas d’un heritage coutumier et lui permettait donc de disposer de la terre en tant que bien propre. Contrairement a ce que l’on observe frequemment en zone forestiere de Cote d’Ivoire, ces ventes de terre peuvent etre considerees comme «completes». Les conditions initiales d’acces a la terre (pas de detenteurs coutumiers de droits fonciers, pas de tutorat, droit fonde dans le defrichement), l’absence d’enjeu foncier autochtone et le caractere de ventes completes des transactions foncieres sont autant d’elements qui contribuent a expliquer l’absence de remise en cause des droits fonciers, y compris dans le contexte socio-politique actuel.

Within the overall STTIS (Science Teacher Training in an Information Society) framework, this paper focuses on transformations of innovative teaching of optics, following a recommended change of approach to optics in the French curriculum. The empirical investigation of how teachers responded to this change, the main results of which are briefly presented here, identified a crucial aspect of the problem. This is the importance of “critical detail'': that is, the fact that the linkage between certain critical details of practice and the fundamental rationale of a teaching sequence is often not easily understood by teachers, even those who are strongly motivated. The paper then discusses the development of guidelines for the design of training materials based on these research findings, which show how teachers typically tend to transform innovations when putting them into practice. We describe the rationale behind and structure of some teacher training materials intended to facilitate awareness and mastery in this respect. © 2004 Wiley Periodicals, Inc. Sci Ed89:13–27, 2005

International audience; Idiopathic Parkinson's disease (PD) is characterized by mesencephalic dopaminergic neuron cell death and striatal dopamine (DA) depletion. The factors involved in the pathogenesis of the disease are still unknown. Transforming growth factor beta1 (TGFbeta1) is increased in the striatum of patients with PD. However, the effect of this increase is not known. Here, we show that overexpression of TGFbeta1, by recombinant adenovirus TGFbeta1 gene transfer, in the mesostriatal system of an MPTP mouse model of PD decreased the number of mesencephalic dopaminergic neurons. This effect also involved more extensive DA depletion in the striatum. Striatal enkephalin mRNA levels are augmented, suggesting a decrease in dopaminergic transmission to the postsynaptic target. In the absence of MPTP, TGFbeta1 greatly decreased the number of dopaminergic neurons in the ventral mesencephalon of fully mature mice. These results show that an increase in TGFbeta1 levels aggravate the parkinsonian status of MPTP mice and may therefore be a risk factor for the development of PD.

The Sinorhizobium meliloti M5N1CS strain produces during fermentation a polyglucuronan and oligoglucuronans β-(1→4) linked and partially acetylated. Following the detection of unsaturated oligoglucuronans in the culture media, a glucuronan lyase (GlyA) associated to the S. meliloti M5N1CS has been identified. In this work, we have studied the degradation by Glya of glucuronans with different degree of substitution by acetate and characterized the oligoglucuronans obtained. We have determined that acetyl residues on glucuronan influence the susceptibility of glucuronan to cleavage by the specific lyase and that 2,3-di-O-Ac-GlcpA residues, closed to the cleavage site, limited the depolymerization of a purified glucuronan, while the degradation of a nascent polymer was not affected.

This paper focuses on difficulties students have in reading images, regarding the understanding of a particular domain, e.g. optics and colour. We concentrated upon what extent teachers were conscious of such difficulties and what they suggested doing to avoid possible pitfalls in this respect. A list of expected obstacles, set up to initiate the study, was shown to be appropriate. It shows that, when they predicted or observed a misunderstanding, the consulted teachers tended to add some elements to a misleading image rather than discussing the symbols that were used, their more or less realistic status and their possible ambiguity. Implications for teacher training and the design of innovative sequences are briefly discussed.

PURPOSE: To evaluate prospectively the feasibility and efficacy of early intensive therapy, including intensified cytoreductive chemotherapy (CT) and high-dose CT (HDCT) followed by autologous stem-cell transplantation (ASCT), in patients with advanced Hodgkin’s disease (HD) who failed to respond completely or relapsed after initial treatment. PATIENTS AND METHODS: Among 533 eligible patients with newly diagnosed stage IIIB-IV HD enrolled in the H89 trial, all 157 patients with induction failure (IF) (n = 67), partial response (PR) of less than 75% (n = 22), or relapse (n = 68) were included in this study. Planned salvage therapy included mitoguazone, ifosfamide, vinorelbine, and etoposide monthly for two to three cycles followed by high-dose carmustine, etoposide, cytarabine, and melphalan with ASCT. RESULTS: With a median follow-up of 50 months, the 5-year survival estimates were 30%, 72%, and 76% for the IF, PR, and relapse groups, respectively (P = .0001), 71% for the 101 patients given HDCT, and 32% for the 48 patients treated without HDCT (P = .0001). Multivariate analysis using time-dependent Cox model indicated that B symptoms at progression, salvage without HDCT, and chemoresistant disease before HDCT were significantly associated with shorter overall survival. CONCLUSION: Early intensive therapy improves the outcomes of patients with advanced HD who failed to respond completely to initial treatment and those who relapsed with adverse prognostic factors. However, for patients with IF and chemoresistant disease, this approach remains unsatisfactory.

Whereas the economics of agrarian contracts is rooted in the contractual paradigm, this paper offer a conceptualization of agrarian contracts as «composite» institutional arrangements, with contractual, conventional and regulatory dimensions. The theoretical and methodological implications of this conceptualization are explored. The paper focuses more specifically on the conventional dimension of agrarian contracts, with the illustration of sharecropping arrangements in Mexico., Alors que l'économie des contrats agraires s'inscrit dans le paradigme contractualiste, cet article propose de conceptualiser les contrats agraires comme des arrangements institutionnels « composites », aux dimensions contractuelle, conventionnelle et réglementaire, ce qui n'est pas sans implications théoriques (recours à un certain éclectisme) et méthodologiques (légitimation d'une démarche comprehensive). Une attention plus particulière est portée à la dimension conventionnelle des contrats agraires, illustrée au travers du contrat de métayage dans le contexte mexicain., Colin Jean-Philippe. Contrats agraires ou conventions agraires ?. In: Économie rurale. N°272, 2002. pp. 57-73.

Background The “tet switch system” was originally described under the tet-off configuration with its components encoded by two separate plasmids. Since then, many virus vectors harbouring tet-off components have been designed and their regulation by tetracycline is widely reported. On the contrary, tet-on regulation by viral vectors is poorly documented. Methods E1-E4-defective adenoviruses harbouring either rtTA or the luciferase gene under a minimal inducible promoter (TK* or CMV*) or both components in a single genome were produced. Using either a double or a single virus strategy, induction of luciferase expression was investigated in various cell lines, in mice muscle and in rat brain. Results Over 400-fold induction can be reached with PC12 and NHA cells using a double virus strategy. Comparison of the background activity of different minimal inducible promoters revealed a significant difference between TK* and CMV* promoters both with the cell culture and the in vivo experiments. Interestingly, a single virus strategy permitted an induction exceeding 600-fold with human astrocyte primary cells. Moreover, the E1-E4-defective adenovirus-mediated tet-on system can be quickly switched off and turned back on again. Depending on the cell line, the level of rtTA derived by the single virus strategy differed, resulting in different efficiencies. Experiments performed in rat striatum and mouse muscle confirmed the importance of rtTA expression and minimal promoter used on both doxycycline-independent expression and induction efficiency. Under appropriated rtTA expression, a 32-fold induction is observed in mouse muscle. Conclusions In the recombinant adenovirus context, the CMV* but not the TK* promoter is sensitive to transcriptional interference resulting in high doxycycline-independent expression. By paying attention to the rtTA expression, moderate and high induction can be obtained in vivo and in vitro accordingly. Copyright © 2002 John Wiley & Sons, Ltd.

International audience; : CCR5 binds the chemokines CCL3, CCL4, and CCL5 and is the major coreceptor for HIV-1 entry into target cells. Chemokines are supposed to form a natural barrier against human immunodeficiency virus, type 1 (HIV-1) infection. However, we showed that their antiviral activity is limited by CCR5 adopting low-chemokine affinity conformations at the cell surface. Here, we investigated whether a pool of CCR5 that is not stabilized by chemokines could represent a target for inhibiting HIV infection. We exploited the characteristics of the chemokine analog PSC-RANTES (N-α-(n-nonanoyl)-des-Ser(1)-[l-thioprolyl(2), l-cyclohexylglycyl(3)]-RANTES(4-68)), which displays potent anti-HIV-1 activity. We show that native chemokines fail to prevent high-affinity binding of PSC-RANTES, analog-mediated calcium release (in desensitization assays), and analog-mediated CCR5 internalization. These results indicate that a pool of spare CCR5 may bind PSC-RANTES but not native chemokines. Improved recognition of CCR5 by PSC-RANTES may explain why the analog promotes higher amounts of β-arrestin 2*CCR5 complexes, thereby increasing CCR5 down-regulation and HIV-1 inhibition. Together, these results highlight that spare CCR5, which might permit HIV-1 to escape from chemokines, should be targeted for efficient viral blockade.

This paper focuses on difficulties linked to situations in physics involving two models: geometrical optics and wave optics. The starting point is an investigation of university-level students’ difficulties. Excerpts from textbooks are given, to illustrate potential difficulties. A content analysis is then presented, underlining two important features required for dealing with such situations: awareness of the status of the drawings, and the “backward selection” of paths of light. These features could provide some guidelines for the designing of innovative teaching strategies.

Astrocytes are a good candidate cell type for brain transplantation: They are endogenous to the CNS, they have efficient secretory machinery, and they play a major role in neuronal support. We assessed the potential of genetically modified primary adult human astrocytes as vehicles for the delivery of secreted molecules in the mammalian CNS. We report that such cells can be efficiently transduced by a recombinant adenoviral vector carrying the human beta-glucuronidase cDNA (Ad/CMV*beta-glu) and that the transduced astrocytes produce large amounts of the enzyme. Released beta-glucuronidase could be captured, in vitro, by primary neurons and astrocytes and by a neuroblastoma cell line and beta-glucuronidase-deficient fibroblasts. Following grafting into the mouse striatum, adult human astrocytes survived and expressed the transgene for at least 8 weeks. Moreover, the dosage of beta-glucuronidase activity within the grafted brains revealed high enzymatic levels at a long distance from the graft. These experiments document the grafting of engineered primary adult human astrocytes, allowing the release of a secreted therapeutic factor throughout the brain.

The aim of this randomized open-label study was to compare a bimonthly with a monthly regimen of 5-fluorouracil (5-FU) and leucovorin for the adjuvant treatment of colon and high-rectum adenocarcinoma. The bimonthly regimen was administered for 2 consecutive days every 14 days as d,L-leucovorin 200 mg/m2 or L-leucovorin 100 mg/m2 as a 2-hour infusion followed by 5-FU bolus of 400 mg/m2 and a 600 mg/m2 5-FU 22-hour continuous infusion (LVSFU2). In the monthly regimen, d,L-leucovorin 200 mg/m2 or L-leucovorin 100 mg/m2 15-minute infusion followed by a 400 mg/m2 15 minute 5-FU bolus was administered for 5 consecutive days every 28 days (FUFOL). Nine hundred five patients with recently resected stage B2 or C colon or high-rectum adenocarcinoma (inferior pole of the tumor subperitoneal) were recruited into the study. Patients were randomized in a 2 x 2 factorial design to receive either LV5FU2 or FUFOL for 24 or 36 weeks. Characteristics of the patients in the two different treatment groups were similar at baseline. Compliance was good. Mean 5-FU dose intensities were 930 mg/ m2/wk and 463 mg/m2/wk for LVSFU2 and FUFOL, respectively. The incidence of maximal grade III-IV toxicities for LVSFU2 and FUFOL was neutropenia 6% and 16% (P < .001), diarrhea 4% and 10% (P < .001), and mucositis 2% and 7% (P < .001), respectively. Maximum grade III-IV toxicities in the LV5FU2 treatment group were significantly lower than in the FUFOL group (10% v 26%; P < .001). Although patients in the LV5FU2 group received twice the dose of 5-FU compared with those in the FUFOL group, LV5FU2 was shown to be less toxic. Efficacy data will be available in 2001.

BACKGROUND The prognostic impact of large mediastinal involvement (mediastinum/thorax [M/T] ratio > 0.33) in advanced Hodgkin disease (HD) and the optimal treatment with chemotherapy or combined treatment remains controversial. METHODS Among 533 assessable patients with Ann Arbor Stage IIIB/IV HD included in the H89 trial, 82 had large mediastinal mass defined on chest X-ray. All patients received induction with six cycles of chemotherapy (mechlorethamine, vincristine, procarbazine, prednisone–doxorubicin, bleomycin, vinblastine or doxorubicin, vinblastine, bleomycin, procarbazine, prednisone); then complete and good partial responders were randomized between two consolidation treatments: 2 cycles of the same chemotherapy or (sub)total lymph node irradiation. RESULTS Among 82 patients with an M/T ratio greater than 0.33, 48 were very large (ratio > 0.45). A large mediastinal mass was associated with supradiaphragmatic disease, younger age, histologic nodular sclerosis, and different sex ratio compared with other H89 trial patients. Biologic parameters and prognostic factors were similar for both groups. Although the major response rate to induction chemotherapy (after 6 cycles) was lower for patients with large mediastinal mass (78% vs. 86%), the 5-year overall survival rate (80% vs. 79%) and event free survival rate (59% vs. 61%) were similar (P = 0.64 and 0.3, respectively). The outcome was the same for patients (74%) with a large mediastinal mass randomized to 1 of the 2 consolidation arms. Analysis of progression showed that 68% (21 of 31) of failures occurred early during treatment and involved the mediastinum in 86% of the cases. CONCLUSIONS For patients with large mediastinal mass and advanced HD who achieved a major response of at least 75% after 6 cycles of chemotherapy, a consolidation radiation therapy can be replaced by 2 additional cycles of chemotherapy. Cancer 2001;92:453–9. © 2001 American Cancer Society.

Sharecropping as a partnership. the a medias contract in the sierra madre oriental - Mexico - Sharecropping is usually explained by a trade-off between tenant's risk aversion and incentives (standard Principal-Agent approach) or between agency costs under various market imperfections, and with risk-neutral agents (transaction costs approach). This Mexican case-study illustrates a situation where contractual rationales refute the standard Principal-Agent model and where share- cropping can be analyzed as a resource pooling device, but without any major role given to moral hazard in contractual choice. In this situation, sharecropping features a partnership rather than agency relationships., Le recours au métayage est usuellement expliqué par un arbitrage entre aversion au risque et incitation du tenancier (approche Principal-Agent standard) ou entre coûts d'agence dans une situation d'imperfection des marchés autres que le marché de la terre, avec des acteurs neutres vis-à-vis du risque (approche par les coûts de transaction). Cette étude des contrats agraires au Mexique illustre une configuration où les logiques contractuelles infirment le modèle Principal-Agent standard et conduisent à analyser le métayage comme un dispositif de mise en commun de ressources dans un contexte d'imperfection des marchés, sans accorder de rôle central à l'aléa moral dans les choix contractuels. Dans la situation étudiée, le métayage relève du partenariat et non d'une relation d'agence., Colin Jean-Philippe, Bouquet Emmanuelle. Le métayage comme partenariat. L'arrangement a médias dans la Sierra Madré orientale. In: Économie rurale. N°261, 2001. pp. 77-92.

The paper highlights the great diversity of economic research on agricultural systems, through the presentation of selected approaches: modern farm management, farming systems research, agricultural household economics, French Africanist rural economics, and behavioral and multidisciplinary systems studies. Major differences among these studies are highlighted, in terms of research aims, organization and issues, type of “systemic” approach followed, theoretical framework, use of formal modeling, and the role of fieldwork. Trends in popularity of the different research types are discussed. The authors recommend integrating an institutional perspective in economic research on agricultural systems and broadening the research agenda.

The extracellular polysaccharide produced by Lactobacillus rhamnosus strain C83 was found to be composed of D-glucose and D-galactose in a molar ratio of 2:3. The primary structure of the polysaccharide was shown by sugar analysis, methylation analysis, FABMS, partial acid hydrolysis and nuclear magnetic resonance (NMR) spectroscopy to consist of a pentasaccharide repeating unit having the following structure: --3)-alpha-D-Glcp-(1--2)-beta-D-Galf-(1--6)-alpha-D-Galp-(1--6 )-alpha-D -Glcp-(1--3)-beta-D-Galf-(1

Resume Objectif de l'etude. — Mise au point pour optimiser l'irradiation des tumeurs cerebrales benignes, la technique de radiotherapie stereotaxique fractionnee permet l'irradiation d'un volume reduit (2, 1 cm3 ; 16 mm de diametre) avec un fractionnement standard. Les resultats d'une analyse retrospective multicentrique sont presentes. Materiel et methodes. — La radiotherapie stereotaxique fractionnee utilise les principes balistiques et dosimetriques de la radiochirurgie : reperage stereotaxique, irradiation par multifaisceaux, collimation secondaire, dosimetrie tridimensionnelle. Le fractionnement est rendu possible par l'utilisation d'un dispositif stereotaxique non invasif et repositionnable. La technique a ete utilisee pour traiter des adenomes hypophysaires (86 patients), des neurinomes de l'acoustique (32 patients), et des meningiomes du sinus caverneux (26 patients). Resultats. — Adenomes hypophysaires: les taux cumules de reponse objective tumorale (42 patients) etaient respectivement de 42 %, 69 % et 88 % a 24, 48 et 60 mois. Les taux cumules de reponse objective hormonale (32 patients) etaient respectivement de 53 %, 75 % et 85 % a 24, 48 et 60 mois. Le risque cumule d'insuffisance hypophysaire radio-induite variait de 18 % pour la GH a 42 % pour la TSH a 48 mois. Aucune autre complication n'a ete energistree. Neurinomes de l'acoustique : 33 tumeurs de diametre inferieur a 25 mm ont ete traitees chez 32 patients. Le controle tumoral a ete assure pour 29 des 33 tumeurs : 14 stabilisations, 15 regressions et trois progressions. Une audition utile a pu etre maintenue chez neuf des dix patients. Seuls trois patients (9 %) avaient une complication persistante. Meningiome du sinus caverneux: il a ete note 17 reponses cliniques sur 19, 20 stabilisations tumorales, une reponse partielle et une progression (22 patients evaluables par IRM). Une cecite unilaterale radio-induite a ete observee. Conclusion. — Pour ces tumeurs benignes, la reduction du volume irradie obtenue par radiotherapie stereotaxique fractionnee semble plus adaptee au traitement des tumeurs benignes de petit volume que la radiotherapie standard. Le fractionnement de la dose reduit le risque de lesion severe des tissus sains en comparaison avec la radiochirurgie qui delivre une dose unique elevee.

CC chemokine receptor 5 (CCR5) is a receptor for chemokines and the coreceptor for R5 HIV-1 entry into CD4 + T lymphocytes. Chemokines exert anti–HIV-1 activity in vitro, both by displacing the viral envelope glycoprotein gp120 from binding to CCR5 and by promoting CCR5 endocytosis, suggesting that they play a protective role in HIV infection. However, we showed here that different CCR5 conformations at the cell surface are differentially engaged by chemokines and gp120, making chemokines weaker inhibitors of HIV infection than would be expected from their binding affinity constants for CCR5. These distinct CCR5 conformations rely on CCR5 coupling to nucleotide-free G proteins ( NF G proteins). Whereas native CCR5 chemokines bind with subnanomolar affinity to NF G protein-coupled CCR5, gp120/HIV-1 does not discriminate between NF G protein-coupled and uncoupled CCR5. Interestingly, the antiviral activity of chemokines is G protein independent, suggesting that “low-chemokine affinity” NF G protein-uncoupled conformations of CCR5 represent a portal for viral entry. Furthermore, chemokines are weak inducers of CCR5 endocytosis, as is revealed by EC 50 values for chemokine-mediated endocytosis reflecting their low-affinity constant value for NF G protein-uncoupled CCR5. Abolishing CCR5 interaction with NF G proteins eliminates high-affinity binding of CCR5 chemokines but preserves receptor endocytosis, indicating that chemokines preferentially endocytose low-affinity receptors. Finally, we evidenced that chemokine analogs achieve highly potent HIV-1 inhibition due to high-affinity interactions with internalizing and/or gp120-binding receptors. These data are consistent with HIV-1 evading chemokine inhibition by exploiting CCR5 conformational heterogeneity, shed light into the inhibitory mechanisms of anti–HIV-1 chemokine analogs, and provide insights for the development of unique anti–HIV molecules.

Our previous studies showed that intrafraction motion needs to be corrected for in frameless radiosurgery. This study was designed to evaluate if verification images can correct for mechanical inaccuracy and intrafraction motion. With proper immobilization and verification images on a regular basis during treatment, mechanical (table-) inaccuracies and intrafraction motion can be corrected for and the absence of PTV-margins warranted. (C) 2013 Elsevier Ireland Ltd. All rights reserved.

Transplantations for neurological disorders are limited by the supply of human fetal tissue. To generate larger numbers of cells of appropriate phenotype, we investigated whether human neural progenitors expanded in vitro could be modified with recombinant adenoviruses. Strong expression of beta-galactosidase was obtained in vitro. Two or three weeks after transplantation of engineered cells to the rat brain, we observed a small percentage of surviving neuroblasts strongly expressing beta-galactosidase in four out of 13 rats. Thus human precursor cells that have been genetically modified using adenoviruses are a promising tool for ex vivo gene therapy of neurodegenerative diseases.

During fermentation, the mutant strain Rhizobium mefliloti M5N1 CS, which induces nodule formation on alfalfa roots, produces a partially acetylated (1 → 4)-β-d-glucuronan. In addition to this exopolysaccharide of high molecular weight, the mutant strain produces oligoglucoronates and cyclic (1 → 2)-β-d-glucans with degrees of polymerization from 17 to 30. Under the conditions applied, magnesium has no effect on cyclic glucan production by the mutant strain, but the succinoglycan production by the wild-type strain Rhizobium meliloti M5N1 increases.

In an evolutionary approach, classical economists understood sharecropping as a tenancy system imposed mainly by tenants' capital constraints. Later, the orthodox neoclassical economics has not been able to offer a satisfactory explanation of sharecropping. Since two decades, New Institutional economists have been analyzing the economic rationality of sharecropping in terms of risk, imperfect markets, asymmetrical information, and transaction costs., L'économie classique présentait le métayage, dans une perspective évolutionniste, comme un mode de faire-valoir rendu indispensable par le faible niveau d'accumulation de capital des tenanciers. Par la suite, l'approche néo-classique orthodoxe n'a pas pu apporter d'explication satisfaisante à l'existence du métayage. Depuis deux décennies, on assiste à un foisonnement d'analyses proposées par des tenants de la Nouvelle Economie Institutionnelle, qui appréhendent la rationalité économique du métayage au regard du risque, de l'imperfection des marchés, des asymétries informationnelles et des coûts de transaction., Colin Jean-Philippe. De Turgot à la nouvelle économie institutionnelle. Brève revue des théories économiques du métayage. In: Économie rurale. N°228, 1995. pp. 28-34.

En Afrique, la question foncière est actuellement dominée par le thème des acquisitions de terre à grande échelle, mais la place des élites nationales dans cette dynamique reste peu traitée. Ce texte présente les premiers résultats d’une recherche sur les acquisitions « marchandes » de terres par les « cadres » en Côte d’Ivoire. Il montre que l’achat pour la réalisation de plantations d’hévéa domine et que les superficies concernées restent relativement limitées. Comme dans le cas de transactions entre villageois (généralement entre autochtones et migrants), les acquisitions foncières impliquant des cadres restent marquées par un enchâssement social. Ces premiers résultats conduisent à relativiser la spécificité des transferts fonciers au bénéfice des cadres par rapport aux transferts n’impliquant que des villageois.

Ce texte explore les déterminants de l'engagement, ou non, des ménages agricoles dans le processus de certification issu de la réforme foncière malgache de 2005. Nos travaux, conduits dans une commune rurale des Hautes Terres, montrent (i) que la principale motivation à la demande de certificat est la recherche d'une sécurisation des droits fonciers en soi, indépendamment d'éventuelles perspectives d'investissements futurs ou de mise sur le marché de la terre, (ii) que les caractéristiques de la parcelle influent tant sur la décision de certifier que sur le choix des parcelles à certifier.

Objective: To study the prognostic impact of O 6 -methylguanine-DNA methyltransferase (MGMT) on newly diagnosed glioblastoma patients being treated with carmustine-releasing wafers (Gliadel®) along with temozolomide (TMZ). Background MGMT promoter methylation status was proposed as a prognostic biomarker for glioblastoma patients. However, the prognostic impact of MGMT on newly diagnosed glioblastoma patients treated using surgical resection and Gliadel® implants followed by Stupp9s protocol is still unknown. Design/Methods: MGMT promoter methylation status and protein expression were analyzed in formalin-fixed, paraffin-embedded tumor specimens obtained from 111 French patients with newly diagnosed glioblastoma. Patients received Gliadel® followed by radiotherapy plus concomitant and adjuvant TMZ chemotherapy, while being enrolled in a French multicenter prospective study. Results: For the whole cohort, median overall survival (OS) and progression-free survival (PFS) were 17.5 and 10.3 months, respectively. Patients with tumors harboring MGMT methylation displayed a significantly longer OS compared to those with wild-type MGMT (21.7 vs . 15.1 months, p=0.025). Similarly, patients with low MGMT protein expression (≤15%) exhibited significantly improved OS compared to those with high MGMT expression (27.0 vs. 15.1 months, p=0.021). The extent of resection was the strongest clinical outcome predictor. In multivariate Cox models adjusted for gender, performance status, and extent of surgery, both MGMT methylation and protein expression were found to be independent prognosticators, which was internally validated using bootstrap resampling techniques. However, no significant correlation was found between protein expression and MGMT methylation status, thus suggesting that the two assays probably assess different biological features. Conclusions: MGMT promoter methylation status and low MGMT expression were both found to be positive prognosticators in newly diagnosed glioblastoma patients treated using surgical resection and Gliadel® implants followed by Stupp9s protocol. Disclosure: Dr. Guillamo has nothing to disclose. Dr. Levallet has nothing to disclose. Dr. Dugue has nothing to disclose. Dr. Vital has nothing to disclose. Dr. Diebold has nothing to disclose. Dr. Menei has nothing to disclose. Dr. Colin has nothing to disclose. Dr. Peruzzy has nothing to disclose. Dr. Emery has nothing to disclose. Dr. Bernaudin has nothing to disclose. Dr. Chapon has nothing to disclose. Dr. Lechapt-Zalcman has nothing to disclose.

Purpose To evaluate long-term outcomes and efficacy of fractionated stereotactic radiotherapy in the treatment of acoustic neuromas. Material and methods Between January 1996 and December 2009, 158 acoustic neuromas were treated by FSR in 155 patients. They received a dose of 50.4Gy, with a safety margin of 1–2mm with a median tumor volume at 2.45mL (range: 0.17–12.5mL) and a median follow-up duration at 60months (range: 24–192). Results FSR was well tolerated in all patients with mild sequelae consisting in radiation-induced trigeminal nerve impairments (3.2%), Grade 2 facial neuropathies (2.5%), new or aggravated tinnitus (2.1%) and VP shunting (2.5%). The treatment failed in four patients (2.5%) who had subsequent surgery respectively at 20, 38, 45 and 84months post-FSR. The local tumor control rates were respectively 99.3%, 97.5% and 95.2% at 3, 5 and >7-year of follow-up. For initial Gardner–Robertson Grade 1 and 2 ANs, the preservation of useful hearing was possible in 54% of the cases; only Grade 1 ANs had stabilized during the course of the follow-up with 71% >7years. However, hearing preservation was not correlated to the initial Koos Stage and to the radiation dose delivered to the cochlea. Tinnitus (70%), vertigo (59%), imbalance (46%) and ear mastoid pain (43%) had greatly improved post-FRS in most patients. Tumor control, hearing preservation and FRS toxicity were quite similar in patients with NF2, cystic acoustic neuroma, prior surgical resection and Koos Stage 4 AN. No secondary tumors were observed. Conclusion FSR is a safe and effective therapeutic for acoustic neuromas and could be an alternative to microsurgery. Compared to radiosurgery, there are no contraindications for fractioned doses of stereotactic radiotherapy especially for Stage-4 tumors and patients at high risk of hearing loss.

This article highlights the role of sharecropping in small-scale, non-traditional export production, through the case of pineapple production in Cote d’Ivoire. The study reveals the diversity of contractual configurations with respect to the same crop, under the same local term of abougnon. Beyond a description of contractual practices, the article explores the rationale for share contracts in a context of imperfect tenancy, labour and credit markets. The analysis of actors’ rationales in entering abougnon contracts points out the role of financing constraints and disequilibrium in the tenancy market. It highlights the secondary role played by transaction costs induced by moral hazard, incentives or – up to the crisis that struck down the sector – production and market risks. This in-depth, localised longitudinal case study relies on first-hand data collected through intensive fieldwork conducted in the village of Djimini-Koffikro in 1983–1984 and 2002–2003, updated in 2010. Cet article met en exergue le role du metayage dans la production d’exportation non traditionnelle a petite echelle, en s’appuyant sur le cas de la production d’ananas en Cote d’Ivoire. L’etude revele la diversite des configurations contractuelles pour une meme culture et sous un meme terme local (abougnon). Au dela d’une description des pratiques contractuelles, cet article examine la logique sous-tendant les contrats de metayage dans un contexte ou les marches de location de terre, du travail et du credit sont imparfaits. L’analyse des raisons pour lesquelles les acteurs passent des contrats d’abougnon met en evidence le role des contraintes de financement et du desequilibre du marche locatif. Elle souligne le role secondaire des couts de transactions induits par l’alea moral, des incitations ou – jusqu’a la crise qui s’est abattue sur ce secteur – des risques de production et de marche. Cette etude de cas longitudinale, approfondie et localisee, s’appuie sur des donnees de premiere main recueillies grâce a un travail intensif de terrain effectue dans le village de Djimini-Koffikro en 1983–1984 et 2002–2003, puis actualisees en 2010.