Les tumeurs de la fosse postérieure (PFT) représentent les deux tiers des tumeurs cérébrales pédiatriques. Les PFT malignes les plus fréquentes sont le médulloblastome (40%), suivie de l'épendymome (10%). La chirurgie, la radiothérapie et/ou la chimiothérapie sont les approches thérapeutiques utilisées à l’heure actuelle. En raison de l'amélioration des traitements, la survie a augmenté de façon significative. Cependant, ces enfants souffrent de déficiences cognitives variées en partie attribuées à la radiothérapie et ce d’autant plus qu’ils sont jeunes. Atténuer les séquelles neurocognitives est devenu ces dernières années un des enjeux majeurs de l'oncologie pédiatrique. Dans cette optique, ce travail examine chez des enfants traités pour une PFT, les relations entre doses de radiothérapie reçues et performances neuropsychologiques en fonction de l’âge, au moyen d’une approche associant la neuroimagerie et la neuropsychologie. La contribution expérimentale s’articule autour de deux principaux axes. Le 1er axe utilise une approche exploratoire pour rendre compte des relations entre l’irradiation des régions cérébrales et le déclin cognitif chez les enfants traités pour une PFT. L’analyse des données met en relation des patterns spatiaux de répartition des doses dans le cerveau avec la variation des scores neuropsychologiques dans le temps (Mémoire de travail, vitesse de traitement, QI). Nos principaux résultats suggèrent une association entre la diminution des capacités en mémoire de travail et l’augmentation des doses (Dose uniforme équivalente, EUD) délivrées aux régions orbitofrontales ; alors qu’un ralentissement de la vitesse de traitement semble être lié à une dose élevée dans les lobes temporaux et la fosse postérieure. Le 2nd axe utilise une approche a priori pour déterminer l’impact de la maladie et des traitements sur le développement de la mémoire épisodique (ME) et des hippocampes, chez de jeunes enfants (2-13 ans). Cette partie se structure autour d’une part de l’analyse des performances des patients lors d’une tâche expérimentale mesurant la ME et d’autre part, d’une analyse longitudinale des volumes hippocampiques de ces enfants pendant le traitement. Nous avons a mis en évidence chez les enfants avec PFT une altération de la ME dépendant de l’âge : Chez les patients plus jeunes (<7 ans), l'altération était globale tandis que chez les plus âgés, elle ne concernait que la reconnaissance à long terme des détails temporels (c'est-à-dire «quand»). L’analyse des données volumiques hippocampiques n’a pas pu être achevée dans le temps de cette thèse, compte tenu de plusieurs difficultés méthodologiques liées notamment au recalage longitudinal des cerveaux en croissance. Ce travail apporte des connaissances nouvelles sur le rôle de certains facteurs dans l’émergence de difficultés cognitives spécifiques. La prévention des séquelles à long terme de ces enfants reste un défi pour les années à venir. / Pediatric posterior fossa tumors (PFT) account for two-thirds of all pediatric brain tumors. The most common malignant PFT is medulloblastoma (40%), followed by ependymoma (10%). Surgery, radiotherapy and/or chemotherapy are the current therapeutic approaches. As a result of the progress of treatment, event-free survival has significantly improved. Unfortunately, these children suffer from many cognitive impairments partly attributed to radiotherapy, especially in young children. Alleviating neurocognitive impairments has become one of the major challenges of pediatric oncology. Using an approach combining neuroimaging and neuropsychology, this work examines the relationship between treatments and neuropsychological performances as a function of age in children treated for PFT. The experimental contribution is based on two main axes. The first axis uses an exploratory approach to investigate the relationship between the decline of intellectual functioning and radiation dose distribution. For this purpose, we analyze, with a whole brain analysis, the relation between regional biological dose and changes over time of different cognitive scores (IQ, processing speed and working memory). Our results suggest a positive association between working memory decline and high dose (Equivalent Uniform Dose, EUD) delivered to the orbitofrontal regions, whereas decline of processing speed seems more related to EUD in the temporal lobes and posterior fossa. The 2nd axis uses a hypothesis-driven approach to determine the susceptibility of episodic memory (EM) impairment and hippocampal alteration in young child PFT patients (2-13yo). This part is structured around two aims: First, the assessment of PFT EM performances, thanks to an EM task, in comparison to Controls; second, the exploration of longitudinal patterns of hippocampal volume as a potential neural substrate underlying EM performance. The main results support the evidence of EM impairment in the PFT condition, which varied according to age: in the younger patients (<7yo) impairment was global while in the older it involved only the long term recognition of temporal details (i.e. ‘When’). However, at this stage of the work, several methodological difficulties mainly related to the registration parameters of the segmentation algorithm prevent us from achieving hippocampal volume analysis. This work brings new knowledge about the role of some risk factors on specific cognitive difficulties. Preventing long-term impairments of these children remains a challenge for years to come.

Hintergrund: RGD-Peptide hemmen kompetitiv die Adhäsionsmoleküle von Linsenepithelzellen (LEC). Ziel unserer Untersuchungen war es herauszufinden, ob diese Peptide in der Lage sind, auch nach Kurzzeitinkubation eine suffiziente Inhibition der Adhäsion bzw. eine Ablösung adhärenter Zellen und damit eine ausreichende Prävention des Nachstars zu bewirken. Außerdem wurde überprüft, ob das von uns verwendete RGD-Peptid eine Toxizität für die Hornhaut aufweist. Material und Methoden: Kulturen boviner und humaner LEC, boviner Hornhautendothelzellen, humane und bovine Linsenkapselexzidate und humane explantierte Hornhäute wurden verwendet. Wir untersuchten die Inhibition der Adhäsion und die Ablösung konfluenter LEC-Layer mittels des zyklischen RGD-Peptids cRGDDFV (Inkubationszeiten von 1 Stunde bzw. 5-7 Tagen und Konzentrationen von 10-4 M, 10-3 M und 2x10-3 M wurden angewandt). Ergebnisse: Wir fanden nach nur einstündiger Inkubation in der Kulturschale eine Adhäsionsinhibition von 48% für bovine LEC und von 100% für humane LEC. Die Differenz zwischen Kontrollpeptid und cRGDDFV war statistisch signifikant (p / Purpose: RGD-peptides competitively inihibit adhesion molecules of the lens epithelial cells (LEC). The purpose of our study was to investigate whether this peptide could be able to inhibit adhesion sufficiently after short term incubation resp. to detach adherent cells and so to prevent posterior capsule opacification (PCO). Also there was proofed if there is any toxicity for the cornea. Methods: Cultures of bovine and human LEC, bovine cornea endothelial cells, humane and bovine fragments of the lens capsule and explanted humane corneas were used. The inhibition of adhesion and the detachment of confluent LEC-layer by the cyclic RGD-peptide cRGDDFV were studied (incubation time was 1 hour resp. 5-7 days and concentrations of 10-4, 10-3 M and 2x10-3 M were used). Results: After one hour incubation time in a culture dish inhibition of adhesion was 48% for bovine LEC resp. 100% for humane LEC. There was a statistically significant difference between the control-peptide-group and cRGDDFV (p

Made available in DSpace on 2015-04-14T13:35:30Z (GMT). No. of bitstreams: 1 438181.pdf: 3961885 bytes, checksum: 1a2e9a9bcf3838013c6755da613f5eb7 (MD5) Previous issue date: 2012-03-30 / INTRODUCTION : Posterior Reversible Encephalopathy Syndrome (PRES) is a clinico-radiological entity that presents with headache, altered mental status, seizure and visual disturbance and is associated with a reversible probably vasogenic edema, predominantly in occipital and parietal lobes. The precise physiopathology remains unclear and there isn t an experimental model of this disorder. OBJECTIVES : The objectives of this paper were (1) the clinical and radiological evaluation of patients with PRES in the Hospital S?o Lucas-PUCRS and (2) the development of a translational model based on clinical features that mimetize this syndrome in pregnants Wistar rats. METHODS : It was performed a review of clinical data, neuroimage and blood basic test of 25 patients with PRES, that were followed in Hospital S?o Lucas-PUCRS in the period from March 15 of 2007 to September 15 of 2011. Based on clinical features and neuroimagem findings, we developed a rat model of PRES using pregnant Wistar rats, which were submitted to a reduction of uterine pressure perfusion (RUPP), measurement of arterial blood pressure with an invasive catheter and a brain anatomo-pathologic study, after Evans s blue venous infusion to verify the permeability of the blood-brain-barrier. RESULTS : Our clinical sample consisted of 25 patients (4 men and 21 women) with mean age of 27,84 years old (range from 2 to 74 years old). The most common causes of PRES reported in this series were associated with pregnant situations that occurred in 11 cases (44%). The symptom more commonly reported was headache in 18 patients (72%). The occipital lobe was the most common topography of the magnetic ressonance abnormality (edema) and occurred in 23 cases (92%). The highest value of the systolic blood pressure presented the mean of 176 mmHg and the highest value of the diastolic blood pressure presented the mean of 95,2 mmHg. Animals submitted to RUPP to simulate the PRES presented increase of the blood-brain-barrier permeability and elevation of blood pressure, when compared with the control animals. CONCLUSION : In our series, PRES occurred predominantly in women and the most frequent triggers were obstetric causes; headache was the most common symptom and the neuroimage findings showed a predominance of posterior alteration suggesting a vasogenic edema due a breakdown of blood brain barrier. The experimental rat model was developed based on these clinical observations, so, we used pregnant rats submitted to reduction of uterine pressure perfusion. We identified in these animals increase of blood pressure and a breakdown of blood brain barrier corroborating to establish an experimental model of PRES. We believe that an experimental model of PRES could be important for future studies allowing a better comprehension of this syndrome. / INTRODU??O : A S?ndrome Encefalopatia Revers?vel Posterior (Posterior Reversible Encephalopathy Syndrome PRES) ? uma entidade clinico-radiol?gica caracterizada por cefal?ia, altera??o do n?vel de consci?ncia, crises convulsivas e altera??o visual e est? associado a um edema provavelmente vasog?nico na subst?ncia branca encef?lica, predominantemente afetando os lobos occipitais e parietais. A fisiopatogenia do PRES permanece desconhecida e n?o existe um modelo experimental de tal dist?rbio. OBJETIVOS : O objetivo desse trabalho ? avaliar apresenta??o cl?nica juntamente com os exames de neuroimagem realizados por pacientes com S?ndrome da Encefalopatia Revers?vel Posterior no Hospital S?o Lucas-PUCRS e baseado nos achados cl?nicos desenvolver um modelo translacional que mimetize essa s?ndrome em ratos Wistar. M?TODOS : Foram revisados os prontu?rio juntamente com os exames de neuroimagem e laboratoriais de 25 pacientes portadores da s?ndrome da encefalopatia revers?vel posterior, os quais foram atendidos no Hospital S?o Lucas-PUCRS no per?odo de 15 de mar?o de 2007 ? 15 de setembro de 2011. A partir das caracter?sticas cl?nicas e de neuroimagem analisadas nesta pesquisa desenvolvemos modelo experimental de PRES com o uso de ratas Wistar gestantes, as quais foram submetidas ? redu??o da press?o de perfus?o uterina (RUPP do ingl?s Reduction of Uterine Pressure Perfusion), medida de press?o arterial invasiva e estudo anatomopatol?gico dos enc?falos dos animais, ap?s infus?o venosa de azul de Evans para avalia??o da permeabilidade da barreira hemato-encef?lica. RESULTADOS : Dos 25 pacientes com PRES analisados com idade m?dia de 27,84 anos (variando de 2 anos a 74 anos), 4 eram homens e 21 mulheres. As causas e/ou desencadeadores mais comumente encontrados foram de origem obst?tricas em 11 casos (44%). O sintoma mais freq?entemente referido foi cefal?ia em 18 pacientes (72%). A topografia mais comumente acometida pelo edema gerado pelo PRES foi occipital em 23 pacientes (92%). O valor da press?o arterial sist?lica m?xima em m?dia foi de 176 mmHg e a press?o arterial diast?lica m?xima em m?dia foi de 95,2 mmHg. Os animais submetidos ao modelo experimental proposto atrav?s do procedimento RUPP para mimetizar o PRES apresentaram altera??es de permeabilidade da barreira hematoencef?lica e eleva??o da press?o arterial quando comparado aos animais controles. CONCLUS?O : Na nossa casu?stica o PRES foi nitidamente predominante em mulheres, os fatores desencadeantes/causais mais frequentes foram os de origem obst?trica, predominando a cefaleia como sintoma; os exames de neuro-imagem confirmaram o predom?nio posterior das altera??es estruturais e sugerem serem decorrentes de edema vasog?nico com quebra da barreira hematoencef?lica. O modelo experimental em ratos Wistar foi desenvolvido baseado nestas observa??es cl?nicas motivo pelo qual utilizamos ratas gestante submetidas a redu??o da press?o de perfus?o uterina. Identificamos nestes animais a quebra da barreira hematoencef?lica corroborando para o estabelecimento do modelo experimental do PRES, o qual pensamos que possa ser de fundamental import?ncia para estudos posteriores que permitam uma melhor compreens?o desta s?ndrome.

Introdução: a ausência de extensão completa do joelho é uma condição limitante que algumas vezes precisa ser tratada invasivamente através da realização da capsulotomia posterior do joelho, uma vez que medidas conservadoras tenham sido esgotadas previamente. No entanto, mesmo com a literatura vigente, ainda não está claro se o procedimento para aquisição de extensão do membro inferior está associado á melhora funcional de pacientes com contratura em flexão do joelho e queixas de dor anterior, bem como se este ganho de extensão pode ser mantido ao longo do tempo. Métodos: nós conduzimos um estudo de coorte retrospectivo de 21 pacientes com contratura em flexão mínima do joelho os quais foram submetidos à capsulotomia posterior do joelho por técnica aberta entre 1990 e 2010. Após 9.19 ± 6.68 anos de follow-up, os níveis funcionais do joelho e média de ângulo de contratura em flexão foram comparados com os dados pré-operatórios e a taxa de recorrência pôde ser estimada. Complicações investigadas incluíram instabilidade do joelho secundária ao procedimento e danos neurovasculares. Resultados: pré-operatoriamente, todos os pacientes (100%) apresentavam scores funcionais de Lysholm classificados como regular ou ruim (média absoluta do score 58.66 ± 13.87, 95%CI 52.35–64.98), e 15 pacientes (72%) apresentaram melhora funcional, com scores bom ou excelente (média de score de Lysholm 87.61 ± 8.81, 95%CI 83.60–91.63) após o período de follow-up. A média pré-operatória do ângulo de flexão do joelho foi de 25.04 ± 9.15 graus (95%CI 20.88–29.21) e diminuiu para 4.28 ± 4.18 graus (95CI% 2.38 – 6.19). Nenhum paciente apresentou complicações relacionadas ao procedimento Conclusão: baseado em nossos resultados, nós concluímos que a capsulotomia posterior do joelho parece ser um procedimento seguro e efetivo para tratar adequadamente pacientes com joelhos dolorosos secundários a contraturas em flexão, com uma baixa taxa de recorrência mesmo após 9.19 anos em média de seguimento. / Background: lack of full extension of the knee is a disabling condition that sometimes needs to be treated invasively by a posterior capsulotomy of the knee, since conservative treatments have been exhaustively attempted. However, it is not clear if the procedure is able to improve anterior symptoms on the knee of patients with flexion contracture and if the full extension acquired can be kept throughout long-time follow-up. Methods: we conducted a retrospective cohort study of 21 patients diagnosed with minimal flexion contracture of the knee who underwent open posterior capsulotomy between 1990 and 2010. After 9.19 ± 6.68 years of follow-up, knee function and mean angle of fixed knee flexion were compared to baseline data and the recurrence rate was estimated. Complications investigated included knee instability and neurovascular damages. Results: all patients (100%) presented with a preoperative Lysholm score classified as poor or fair (mean, 58.66 ± 13.87, 95%CI 52.35–64.98), but 15 patients (72%) experienced an improvement to good or excellent scores (mean, 87.61 ± 8.81, 95%CI 83.60–91.63) after long-time follow-up. The mean preoperative angle of fixed flexion was 25.04 ± 9.15 degrees (95%CI 20.88–29.21) and it decreased to 4.28 ± 4.18 degrees (95CI% 2.38 – 6.19, after the follow-up. Conclusion: Based on these results, we conclude that posterior capsulotomy of the knee proved to be a safe and effective procedure to treat properly patients with painful knees secondary to lack of full extension with a low rate of recurrence even after a long-term follow-up.

Introdução: A partir de relatos casos de opacifiação da lente intraocular acrílica hidrofílica Ioflex (Mediphacos, Belo Horizonte, Brasil), muitas vezes utilizada em mutirões de catarata para pessoas carentes, avaliamos a frequência das complicações oculares relacionadas com o implante desta lente quatro anos após a cirurgia, bem como seus efeitos a longo prazo na eficiência da cirurgia de catarata. Métodos: Foi selecionada amostra aleatória com 102 indivíduos submetidos à cirurgia de catarata com implante da lente intraocular Ioflex, em campanha comunitária no interior de Pernambuco, Brasil, quatro anos após a cirurgia. Um total de 31 pacientes não foi localizado e treze (18,3%) não compareceram para o exame. Assim, 58 pacientes (87 olhos) foram examinados. Para o cálculo da frequência da opacificação da cápsula posterior e para a avaliação da eficiência da cirurgia da catarata, foi selecionado apenas um olho de cada paciente. Os sujeitos foram submetidos a exame oftalmológico completo. Pacientes com redução da acuidade visual decorrentes das complicações pós-operatórias foram encaminhados para tratamento. O custo desses eventuais tratamentos foi estimado para análise da eficiência da cirurgia de catarata com a lente Ioflex. Para avaliação dos índices de opacificação da cápsula posterior as variáveis foram expressas por média e desvio padrão. Foi usado o teste t de Student\'s para análise de diferenças entre amostras independentes e pareadas. Resultados: Seis olhos (7%) apresentaram opacificação da lente intraocular. Nenhuma doença ou fator ambiental foi relacionado à opacificação da lente. A opacificação da cápsula posterior foi detectada em 39 (67%) olhos, sendo 24 (41,3%) olhos submetidos ao tratamento com laser para recuperação da acuidade visual. O custo total do tratamento das complicações pós-operatórias representou 6,3% do orçamento cirúrgico inicial. O custo adicional foi de $9,03 dólares por paciente para manter a boa acuidade visual. Conclusão: A lente intraocular acrílica hidrofílica Ioflex apresentou elevada frequência de complicações pós-operatórias tardias relacionadas à própria lente, reduzindo, a longo prazo, a eficácia e eficiência da cirurgia de catarata / Introduction: Based on reports of Ioflex hydrophilic acrylic intraocular lens opacification (Mediphacos, Belo Horizonte, Brazil), used in cataract surgeries for underserved communities, we evaluated the ocular complications related to the intraocular lens implant, four years after surgery, as well as its effects on the visual efficiency of long-term cataract surgery. Methods: A random sample of 102 patients that underwent cataract surgery and Ioflex intraocular lens implantation, in a community campaign in the rural area from Pernambuco, Brazil, four years after surgery. A total of 31 patients could not be located and 13 (18.3%) were not present for examination. Thus, 58 patients (87 eyes) were available for examination. In order to calculate the frequency of posterior capsule opacification and to evaluate the efficiency of cataract surgery, only one eye was selected from each patient. The subjects underwent a complete ophthalmological examination. Patients with reduced visual acuity due to postoperative complications were referred for treatment. The costs of these treatments were estimated for the analysis of the efficiency of the cataract surgery with the Ioflex lens in the long term period. For the evaluation of posterior capsule opacification rates the variables were expressed by means and standard deviation. The Student\'s t test was used for analysis the differences between independent and paired samples. Results: Six eyes (7.0%) had intraocular lens opacification. No disease or environmental factor could be related to intraocular lens opacification. Posterior capsule opacification was detected in 39 (67%) eyes, and 24 (41.3%) eyes were submitted to laser treatment for visual acuity recovered. The total cost of postoperative complications treatment represented 6.3% from the initial budget of the whole patients group evaluated. The additional costs to maintain a good visual outcome was USD $9.03 per patient with Ioflex lens implantation. Conclusion: The Ioflex hydrophilic acrylic intraocular lens had high rates of postoperative complications related to the intraocular lens itself, decreasing effectiveness efficiency in long-term cataract surgery

No description available.

El presente Trabajo de tesis fue elaborado con la finalidad de determinar el impacto financiero de la medición posterior de Propiedad, Planta y Equipo en el sector de bebidas no alcohólicas de consumo masivo en Perú, 2017. Por consiguiente, la investigación se cimentará en aplicar la Norma Internacional de Contabilidad 16 (en adelante, NIC 16) “Propiedad, Planta y Equipo” y la Norma Internacional de Contabilidad 36 (en adelante, NIC 36) “Deterioro del valor de los activos”. Esta investigación se basará en las empresas del sector de bebidas no alcohólicas de consumo masivo, categoría denominada “Soft Drinks”. Este mercado está compuesto por bebidas carbonatadas, agua embotellada, néctares, jugos, bebidas energizantes, entre otras. El rubro más importante del total de activos en los EEFF de las compañías del sector es Propiedad, Planta y Equipo (PPE). Representa aproximadamente el 55% del total de activos. Por lo que, se considera tan importante analizar la medición posterior de PPE para que se tenga la mejor representación fiel de sus Estados Financieros. En el marco teórico se analizan los conceptos de ambas NICs y se desarrolla cómo está compuesto el sector en estudio y sus tendencias a futuro. Luego, en el plan de investigación se define el problema, hipótesis y objetivos. Después, se desarrolla la metodología donde se utilizarán instrumentos cualitativos, tales como entrevistas a profundidad e instrumentos cuantitativos, tales como encuestas. Ambos instrumentos se realizaron a expertos en el sector de bebidas no alcohólicas de consumo masivo y a socios de las más importantes empresas auditoras del país (PWC Perú y EY Perú). Asimismo, se desarrolla un caso práctico donde se cuantificará aplicar un nuevo modelo de medición posterior, el deterioro de activos y el impacto en los ratios financieros. Finalmente, en el capítulo de desarrollo se muestran los resultados de los instrumentos y en el capítulo de análisis se evalúan los efectos obtenidos con las hipótesis planteadas. Se concluye que la medición posterior de Propiedad, Planta y Equipo impacta en la situación financiera y económica de las empresas del sector bebidas no alcohólicas de consumo masivo en el Perú, 2017. / The present Thesis work was developed with the purpose of determine the financial impact of the subsequent measurement of property, plant and equipment in the non-alcoholic beverage sector of mass consumption in Peru, 2017. Therefore, the research will be based on the International Accounting Standard 16 (hereinafter, IAS 16) "Property, Plant and Equipment" and the International Accounting Standard 36 (hereinafter, IAS 36) "Impairment of assets”. This research is based on companies in the non-alcoholic beverage of mass consumption industry, category called “Soft Drinks”. This market is composed by carbonated drinks, bottled water, nectars, juices, energy drinks and others. The most important item of total assets in this sector is "Property, Plant and Equipment". It represents approximately 55% of total assets. Therefore, it is considered so important to analyze the subsequent measurement of PPE to have the best faithful representation of the Financial Statements. In the theoretical framework, the concepts of both NICs are analyzed and the composition of sector under study and its future trends. Then, in the research plan, the problem, hypothesis and objectives are defined. After that, the methodology is developed where qualitative instruments will be used, like depth interviews and quantitative instruments, such as surveys. Both instruments were made to experts in the non-alcoholic beverages sector and to partners of the most important audit companies of this country (PWC Peru and EY Peru). In addition, a case study will be developed to quantify the application of a new model of subsequent measurement, the impairment of assets and the impact on financial ratios. Finally, in the development chapter, the results of the instruments are shown and in the chapter of analysis the effects obtained with the hypotheses proposed are evaluated. It is concluded that the subsequent measurement of Property, Plant and Equipment impacts on the financial and economic situation of companies in the sector of non- alcoholics mass consumption in Peru, 2017. / Tesis

Contexte : Jusqu’à 90% des fumeurs qui tentent d’arrêter de fumer vont rechuter dans l’année suivant la date d’arrêt. L’impulsivité, au même titre que le « craving », a démontré être un bon facteur de prédiction de la rechute tabagique. Ainsi, la présente étude visait à évaluer, à l’aide de la neuroimagerie fonctionnelle, l’influence de l’impulsivité sur les mécanismes neuronaux du « craving » de la cigarette. Parmi les régions cérébrales impliquées dans le « craving » de la nicotine, les cortex préfrontal dorsolatéral, orbitofrontal et cingulaire sont d’importantes structures dans les processus de contrôle de soi. Méthodes : 31 fumeurs chroniques ont passé une session de neuroimagerie durant laquelle ils devaient regarder des images appétitives de cigarettes et des images neutres. Ils ont ensuite dû inscrire le « craving » ressenti à la vue des images et répondre à un questionnaire portant sur les traits de personnalité de l’impulsivité (BIS-11). Résultats : Tel qu’attendu, le score d’impulsivité était positivement corrélé au « craving » rapporté par les participants à la vue d’images de cigarettes. Au niveau cérébral, plus les fumeurs présentaient de forts traits d’impulsivité, moins grande était l’activité du cortex cingulaire postérieur (CCP) durant le « craving ». Enfin, l’activité du CCP présentait une connectivité fonctionnelle négative avec l’insula, le cortex préfrontal dorsolatéral et le cortex cingulaire antérieur. Conclusions : Comme le CCP est le siège des processus de mentalisation et de référence à soi, nous suggérons que plus les fumeurs étaient impulsifs, moins ils prenaient conscience de leur état et moins ils en exerçaient un contrôle, donc plus ils ressentaient de forts « cravings ». En poussant plus loin, nos résultats mettent l’accent sur l’aspect identitaire (le soi, les mémoires autobiographiques) et l’aspect d’introspection en toxicomanie : deux avenues à explorer. / Background: 90% of cigarette smokers attempting to quit smoking relapse by one-year following their quit date. Impulsivity, as well as cue-induced cravings, have been shown to be good predictors of relapse for tobacco smoking; however, no study to date has examined their interaction and its neural substrates. The goal of this study was to determine the neural influence of trait impulsivity during functional imaging of cue-induced cigarette cravings. Among the brain regions involved in nicotine craving, the dorsolateral prefrontal cortex, the orbitofrontal as well as the cingulate cortex all play a significant role in self-control processes. Methods: Thirty-one chronic smokers passively viewed appetitive smoking-related and neutral images while being scanned. Participants also reported their level of craving and completed the BIS-11, a measure of trait impulsivity. Results: As hypothesized, we observed a significant positive relationship between impulsivity scores and reported craving. Impulsivity scores were negatively correlated with activity in the posterior cingulate cortex (PCC). The insula, dorsal anterior cingulate cortex and dorsolateral prefrontal cortex presented a negative connectivity with the PCC. Conclusions: Given that the PCC is involved in mentalization and self-relevant processing, it is possible that greater trait impulsivity in smokers is associated to a lower tendency to understand and use one’s mental and physical state to guide behavior. This may weaken their capacity for self-control and consequently, promotes more automatic and stronger cue-elicited smoking urges. Furthermore, our results highlight the important but undervalued role of identity (the self and autobiographic memories) and mindfulness in addiction.

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In the paper at hand we apply it to Bayesian statistics to obtain "Fuzzy Bayesian Inference". In the subsequent sections we will discuss a fuzzy valued likelihood function, Bayes' theorem for both fuzzy data and fuzzy priors, a fuzzy Bayes' estimator, fuzzy predictive densities and distributions, and fuzzy H.P.D .-Regions. (author's abstract) / Series: Forschungsberichte / Institut für Statistik