971 resultados para aggressive displays
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In line with the rights and incentives provided by the Bayh-Dole Act of 1980, U.S. universities have increased their involvement in patenting and licensing activities through their own technology transfer offices. Only a few U.S. universities are obtaining large returns, however, whereas others are continuing with these activities despite negligible or negative returns. We assess the U.S. universities’ potential to generate returns from licensing activities by modeling and estimating quantiles of the distribution of net licensing returns conditional on some of their structural characteristics. We find limited prospects for public universities without a medical school everywhere in their distribution. Other groups of universities (private, and public with a medical school) can expect significant but still fairly modest returns only beyond the 0.9th quantile. These findings call into question the appropriateness of the revenue-generating motive for the aggressive rate of patenting and licensing by U.S. universities.
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Neuroblastoma (NBL) is the commonest extra-cranial solid tumor in children and the leading cause of cancer related deaths in childhood between the age of 1 to 4 years. NBL may behave in very different ways, from the less aggressive stage 4S NBL or congenital forms that may resolve without treatment in up to 90% of the children, to the high-risk disseminated stage 4 disease in older children with a cure rate of 35 to 40%. Initial staging is crucial for effective management and radiolabeled metaiodobenzylguanidine (MIBG) with iodine-123 is a powerful tool with a sensitivity around 90% and a specificity close to 100% for the diagnosis of NBL. MIBG scintigraphy is used routinely and is mandatory in most investigational clinical trials both for the initial staging of the disease, the evaluation of the response to treatment, as well as for the detection of recurrence during follow-up. With respect to outcome of children presenting disseminated stage 4 NBL, the role of post-therapeutic [(123)I]MIBG scan has been investigated by several groups but so far there is no consensus whereas a complete or very good partial response as assessed by MIBG may be of prognostic value. NBL needs a multimodality approach at diagnosis and during follow-up and MIBG scintigraphy keeps its pivotal role, in particular with respect to bone marrow involvement and/or cortical bone metastases.
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PURPOSE OF REVIEW: To review the current experience with angiogenesis inhibitors in the treatment of gliomas. RECENT FINDINGS: Antiangiogenic therapy has recently reached the clinic with the approval of bevacizumab for recurrent glioblastomas. A number of promising antiangiogenic and vasculature-modifying agents are under investigation for newly diagnosed and recurrent malignant gliomas. A recurrence under ongoing or after antiangiogenic therapy is often characterized by a more aggressive and, in particular, invasive phenotype. SUMMARY: Despite impressively high radiological response rates in patients with recurrent malignant glioma, the duration of response is usually short-lived, and the observed effect to a large extent may be due to normalization of the disrupted blood-brain barrier and less due to a direct antitumor effect. Overall survival remains poor. Induction of invasive phenotypes and escape with proangiogenic alternative pathways are contributing to resistance. Investigation of combination regimes targeting several pathways will determine the possibilities to overcome the resistance to antiangiogenic therapy in malignant gliomas. This article summarizes the results of recent clinical trials in this field, points towards mechanisms of resistance arising under angiogenesis inhibition and discusses the challenges for the future.
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AIM: To describe the incidence of retinocytomas, their variability at presentation and their growth patterns both before and after regression.¦METHODS: Medical notes of the 525 patients of the Jules-Gonin Eye Hospital Retinoblastoma Clinic between 1964 and 2008 were reviewed and the charts of 36 patients with retinocytomas and/or phthisis bulbi were selected.¦RESULTS: The proportion of patients with retinocytomas and/or phthisis bulbi was 3.2%. The mean age at diagnosis was 28.7±17 years. Five tumours presented a cystic pattern (5.8%). Evidence of aggressive exophytic disease prior to spontaneous regression was documented in two eyes, and of invasive endophytic disease (regressed vitreous seeding or internal limiting membrane disruption) in three eyes. Twenty patients were followed with a mean follow-up of 44±60 months. Tumour growth was observed in 16% cases, benign cystic enlargement in 4% and malignant transformation in 12%.¦CONCLUSION: This large study of retinocytomas substantially expands the published features of retinocytoma by describing the cystic nature of some retinocytomas as well as clinical characteristics of the endophytic and exophytic preregression growth patterns. The authors report two different patterns of reactivation: benign cystic enlargement and malignant transformation with or without cystic growth. Higher than previously reported frequency of growth and possible life-threatening complications impose close lifetime follow-up of retinocytoma patients.
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Although body colouration is often used in social interactions, few studies have tested whether colouration is linked to a suite of behavioural traits. In the present study, we examined whether among captive adult male Eastern Hermann's tortoises (Eurotestudo boettgeri) behavioural patterns covary with eumelanic colouration of the shell. Dark eumelanic males were more aggressive in male-male confrontations and bolder towards humans. These relationships were independent of body size and ambient temperature. Activity level and exploration were not significantly associated with colouration. We conclude that at least in captivity shell colouration predicts agonistic behaviour towards conspecifics and fearfulness towards human (i.e. boldness).
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Studying the geographic variation of phenotypic traits can provide key information about the potential adaptive function of alternative phenotypes. Gloger's rule posits that animals should be dark-vs. light-colored in warm and humid vs. cold and dry habitats, respectively. The rule is based on the assumption that melanin pigments and/or dark coloration confer selective advantages in warm and humid regions. This rule may not apply, however, if genes for color are acting on other traits conferring fitness benefits in specific climes. Covariation between coloration and climate will therefore depend on the relative importance of coloration or melanin pigments and the genetically correlated physiological and behavioral processes that enable an animal to deal with climatic factors. The Barn Owl (Tyto alba) displays three melanin-based plumage traits, and we tested whether geographic variation in these traits at the scale of the North American continent supported Gloger's rule. An analysis of variation of pheomelanin-based reddish coloration and of the number and size of black feather spots in 1,369 museum skin specimens showed that geographic variation was correlated with ambient temperature and precipitation. Owls were darker red in color and displayed larger but fewer black feather spots in colder regions. Owls also exhibited more and larger black spots in regions where the climate was dry in winter. We propose that the associations between pigmentation and ambient temperature are of opposite sign for reddish coloration and spot size vs. the number of spots because selection exerted by climate (or a correlated variable) is plumage trait-specific or because plumage traits are genetically correlated with different adaptations.
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Esophageal intramural pseudodiverticulosis is a rare pathology whose etiology is unknown, but which is frequently associated with three highly prevalent entities: esophageal reflux disease, esophageal candidosis and alcoholic esophagitis. With conservative treatment the course of these pathologies is usually benign. However, some severe cases are resistant to conservative treatment and may require more aggressive management. We here present the case of patient suffering from a severe esophagitis complicated by chronic mediastinitis with life-threatening repercussions, requiring esophagectomy as treatment.
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The human brain displays heterogeneous organization in both structure and function. Here we develop a method to characterize brain regions and networks in terms of information-theoretic measures. We look at how these measures scale when larger spatial regions as well as larger connectome sub-networks are considered. This framework is applied to human brain fMRI recordings of resting-state activity and DSI-inferred structural connectivity. We find that strong functional coupling across large spatial distances distinguishes functional hubs from unimodal low-level areas, and that this long-range functional coupling correlates with structural long-range efficiency on the connectome. We also find a set of connectome regions that are both internally integrated and coupled to the rest of the brain, and which resemble previously reported resting-state networks. Finally, we argue that information-theoretic measures are useful for characterizing the functional organization of the brain at multiple scales.
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We study managerial incentives in a model where managers take notonly product market but also takeover decisions. We show that the optimalcontract includes an incentive to increase the firm's sales, under bothquantity and price competition. This result is in contrast to the previousliterature and hinges on the fact that with a more aggressive manager rivalfirms earn lower profits and are willing to sell out at a lower price. \\However, as a side--effect of such a contract, the manager might take overmore rivals than would be profitable.
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Summary Mood disorders are among the most prevalent, psychosocial^ debilitating, chronic and relapsing forms of psychiatric illnesses. Despite considerable advances in their characterization, the heterogeneous nature of susceptibility factors and patient's symptoms could account for the lack of totally effective and remissive treatment. The neurobiological hypothesis of mood disorders etiology has evolved since the monoamine and neurotrophin theories and current evidence is pointing toward their integration in a broader polygenic epistatic model resulting in defective neuroplasticity of circuitries involved in emotion processing. Consequently, the unraveling of molecular underpinning pathways involved in neuronal plasticity, commonly altered among mood disorder syndromes and symptoms, should shed light on their etiology and provide new drug target. The transcription factor CREB has been critically involved in the long-lasting forms of neuronal plasticity and in the regulation of several mood disorders susceptibility genes. In addition, altered CREB activity has been associated with mood disorders pathophysiology and pharmacotherapy. Interestingly, the newly-identified protein CREB-regulated transcription coactivator 1 (CRTC1) was shown by previous studies in the laboratory to be a neuroactivity- dependent cAMP and calcium sensor, a potent activator of CREB-dependent transcription and involved in neuroplasticity mechanisms associated with long-term synaptic potentiation. Furthermore, the major mood disorder susceptibility gene Bdnf was suggested to be transcriptional regulated by CRTC1. Therefore, we aimed to investigate a role for CRTC1 in mood disorders by generating and characterizing a Crtcl deficient mouse model at the behavioral and molecular levels. Interestingly, their comprehensive characterization revealed a behavioral profile mirroring several major symptoms comorbid in mood disorders, including altered social interactions, aggressive behaviors, obesity, psychomotor retardation, increased emotional response to stress, decreased sexual drive and depression-like behaviors. To investigate the molecular mechanisms underlying these pathological behaviors and the implication of CRTC1 in the regulation of CREB-regulated genes in vivo, we also quantified transcript levels of several relevant CREB-regulated susceptibility genes in brain structures involved in the pathophysiology of mood disorders. Strikingly, we found the underexpression of primary components of the neurotrophin system: Bdnf and its cognate receptor TrkB, a marked decrease in the Nr4a family of transcription factors, implicated in neuroplasticity and associated with dopamine-related disorders, as well as in several other relevant CREB regulated genes. Moreover, neurochemical analysis revealed that Crtcl null mice presented alteration in prefrontal cortical monoamine turnover as well as in hippocampal and accumbal serotonin levels, similarly associated with mood disorders etiology and pharmacotherapy. Together, the present thesis supports the involvement of CRTC1 pathway hypofunction in the pathogenesis of mood disorders and specifically in pathological aggression, obesity and depression-related behavior comorbidities. Ultimately, CRTC1 may represent an interesting antidepressant, antiaggressive or mood stabilizer drug target candidate through the modulation of major CREB regulated susceptibility genes. Les troubles de l'humeur comptent parmi les maladies psychiatriques les plus prévalentes, psychosocialement débilitantes, chroniques et avec le plus grand risque de rechute. Malgré de considérable avancées dans leur caractérisation, la nature hétérogène des facteurs de susceptibilité et des symptômes présentés par les patients, semble justifier l'absence de traitement entraînant une rémission complète de la maladie. L'hypothèse de l'étiologie neurobiologique des troubles de l'humeur a évolué depuis la théorie des monoamines et des neurotrophines. Actuellement, elle tend à les englober dans un modèle polygénique épistatique induisant une déficience de la neuroplasticité des circuits impliqué dans la régulation des émotions. Par conséquent, il apparaît particulièrement relevant de caractériser des voies moléculaires impliquées dans la plasticité neuronale, communément altérées parmi les différents syndromes et symptômes des maladies de l'humeur, afin d'améliorer leur compréhension ainsi que de proposer de nouvelles cibles thérapeutiques potentielles. Le facteur de transcription CREB a été de façon répétée et cohérente impliqué dans les mécanismes à long terme de la plasticité neuronale, ainsi que dans la régulation de plusieurs gènes de susceptibilité aux maladies de l'humeur. De plus, une altération dans l'activité de CREB a été impliqué dans leur étiologie et pharmacothérapie. De façon intéressante, des résultats préliminaires sur la protéine récemment découverte CREB-regulated transcription coactivator 1 (CRTC1) ont indiqué que son activation était dépendante de l'activité neuronale, qu'il était un senseur du calcium et de l'AMPc, ainsi qu'un coactivateur de CREB requis et puissant impliqué dans les mécanismes de plasticité neuronale associés à la potentialisation à long terme. En outre, des résultats ont suggéré que le gène majeur de susceptibilité Bdnf est régulé par CRTC1. Ainsi, notre objectif a été d'investiguer un rôle éventuel de CRTC1 dans les maladies de l'humeur en générant et caractérisant une lignée de souris déficiente pour Crtcl, tant au niveau comportemental que moléculaire. De façon intéressante, leur caractérisation détaillée a révélé un profil comportemental reflétant de nombreux aspects des maladies de l'humeur incluant une altération des interactions sociales, une agression pathologique, l'obésité, un retard psychomoteur, une réponse émotionnelle au stress accrue, une diminution de la motivation sexuelle, et des comportements reliés à la dépression. Afin d'investiguer les mécanismes moléculaires sous- jacents cette altération du comportement, ainsi que l'implication de CRTC1 dans l'expression des gènes régulés par CREB in vivo, nous avons quantifié les niveaux de transcrits de plusieurs gènes de susceptibilité régulés par CREB et impliqués dans la physiopathologie des maladies de l'humeur. Remarquablement, nous avons trouvé la sous-expression de composants primordiaux du système neurotrophique: Bdnf et son récepteur TrkB, une diminution majeure de la famille des facteurs de transcription Nr4a, impliqués dans la neuroplasticité et associés à des désordres liés à la dopamine, ainsi que de nombreux autres gènes relevants régulés par CREB. De plus, une analyse neurochimique a révélé que les souris déficientes pour Crtcî présentent une altération du turn-over des monoamines du cortex préfrontal ainsi que des niveaux hippocampaux et accumbaux de sérotonine, associés de façon similaire dans l'étiologie et la pharmacothérapie des maladies de l'humeur. Vue dans son ensemble, la présente thèse supporte l'implication d'une sous-régulation de la voie de CRTCI dans la pathogenèse des maladies de l'humeur ainsi que dans la comorbidité de l'agression pathologique, l'obésité et la dépression. En conclusion, CRTCI pourrait représenter une cible médicamenteuse intéressante aux propriétés antidépressante, antiagressive ou stabilisatrice de l'humeur au travers de la modulation de gènes de susceptibilité majeurs régulés par CREB.
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Graphical displays which show inter--sample distances are importantfor the interpretation and presentation of multivariate data. Except whenthe displays are two--dimensional, however, they are often difficult tovisualize as a whole. A device, based on multidimensional unfolding, isdescribed for presenting some intrinsically high--dimensional displays infewer, usually two, dimensions. This goal is achieved by representing eachsample by a pair of points, say $R_i$ and $r_i$, so that a theoreticaldistance between the $i$-th and $j$-th samples is represented twice, onceby the distance between $R_i$ and $r_j$ and once by the distance between$R_j$ and $r_i$. Self--distances between $R_i$ and $r_i$ need not be zero.The mathematical conditions for unfolding to exhibit symmetry are established.Algorithms for finding approximate fits, not constrained to be symmetric,are discussed and some examples are given.
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O objectivo deste trabalho foi de propor propostas de revitalização dos patrimónios arquitectónicos, históricos e culturais da cidade de Ponta do Sol, no intuito de que essa acção pudesse contribuir, de forma significativa, para a preservação dos patrimónios e um possível crescimento económico de Santo Antão, sobretudo do ponto de vista turístico. A cidade de Ponta do Sol, no passado, teve grande importância no que tange à produção e escoamento de vários produtos a exemplo do café, aguardente e quina, tanto para as outras ilhas como para países europeus. Mantém em seu espaço várias e belas construções dos tempos coloniais, entretanto esquecidas, e muitas delas já destruídas e outras encontrando-se em elevado estado de degradação. Além disso, possui uma grande presença judaica e também uma diversidade de herança histórica e cultural, que precisa continuar existindo para que não se perca a identidade cultural da comunidade, uma vez que há presença de tentativas de homogeneização da cultura, imposta principalmente pelos países desenvolvidos e pela globalização. Sendo assim, a preservação e revitalização dos edifícios, tanto público como privado, como do centro histórico em geral, poderá servir de base promotora para o fortalecimento da actividade turística da cidade. Para isso utilizaram-se como fontes bibliográficas, vários documentos, livros diversos, entrevistas, fotografias e trabalho de campo. Depois, com a recolha de dados foi possível constatar que a cidade de Ponta do Sol está atravessando um processo de degradação e modernização. Apesar de ainda activo e vivo, o centro está-se deteriorando, e se não houver intervenções que revertam esse processo, este perderá muito da sua identidade, da sua história-cultural e principalmente os seus patrimónios. Mas, propostas, projectos intervencionistas e acções executoras podem ainda reverter parte dessa situação e dando soluções ao centro da Cidade. Algumas propostas serão implementadas e até mesmo aglutinadas a novas propostas, podendo ser benéficas tanto para a cidade como também para a população. The aim of this work is to make proposals for the revitalization of the historic, cultural and architectural heritage of the city of Ponta do Sol, hoping that this action could contribute in a meaningful way to preserve the patrimony and the possible economic growth of Santo Antão, an island which is particularly considered for the production and trade of different products, especially coffee, liquor and quinine for other islands as well as for European countries. It displays several beautiful colonial constructions. However, they have been forgotten and some of degradation. Besides, this city hosts a great Judaic presence and also some diversity of the cultural identity, since there is the presence of attempts for the homogenization of the culture, imposed mainly by developed countries and the globalization. Thus, the preservation and revitalization of both public and private buildings as well as of the historic centre in general, can serve of a promotion basis for the strength of the historic activity in this town. That´s why a lot of documents, several books, interviews, photos, and field work as local evidence were used as bibliography. Afterwards, with the collected data it was possible to notice that the city of Ponta do Sol is facing a process of degradation and modernization. In spite of still being active and alive, the center is up deteriorating and if on interventions are made to revert this process, it will lose a lot of its identity, cultural history and mainly its patrimony. But proposals, interventionist projects and executive actions can still revert part of this situation and get solutions for the City centre. Some proposal which will be implemented and even be agglutinated to new proposal can be helpful for the city as well as for the population.
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There is very limited data on isolated systemic relapses of primary central nervous system lymphomas (PCNSL). We retrospectively reviewed the clinical characteristics and outcome of 10 patients with isolated systemic disease among 209 patients with PCNSL mainly treated with methotrexate-based chemotherapy (CT) with or without radiation therapy (RT). Isolated systemic relapse remained rare (4.8%, 10/209 patients). Median time from initial diagnosis to relapse was 33 months (range, 3-94). Sites of relapse were mostly extranodal. Three patients presented with early extra-cerebral (EC) relapse 3, 5 and 8 months from the beginning of initial treatment, respectively, and 7 patients had later relapses (range, 17-94 months). Treatment at relapse included surgery alone, RT alone, CT with or without radiotherapy, or CT with autologous stem cell transplantation (ASCT). Median overall survival (OS) after relapse was 15.5 months (range, 5.8-24.5) compared to 4.6 months (range, 3.6-6.5) for patients with central nervous system (CNS) relapse (p = 0.35). In conclusion, isolated systemic relapses exist but are infrequent. Early EC relapse suggests the presence of systemic disease undetectable by conventional evaluation at initial diagnosis. Patient follow-up must be prolonged because systemic relapse can occur as late as 10 years after initial diagnosis. Whether EC relapses of PCNSL have a better prognosis than CNS relapses needs to be assessed in a larger cohort. Copyright © 2010 John Wiley & Sons, Ltd.
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Acute organophosphate (OP) intoxication is associated with many symptoms and clinical signs, including potentially life-threatening seizures and status epilepticus. Instead of being linked to the direct cholinergic toxidrome, OP-related seizures are more probably linked to the interaction of OPs with acetylcholineindependent neuromodulation pathways, such as GABA and NMDA. The importance of preventing, or recognizing and treating OP-related seizures lies in that, the central nervous system (CNS) damage from OP poisoning is thought to be due to the excitotoxicity of the seizure activity itself rather than a direct toxic effect. Muscular weakness and paralysis occurring 1-4 days after the resolution of an acute cholinergic toxidrome, the intermediate syndrome is usually not diagnosed until significant respiratory insufficiency has occurred; it is nevertheless a major cause of OP-induced morbidity and mortality and requires aggressive supportive treatment. The condition usually resolves spontaneously in 1-2 weeks.Treatment of OP intoxication relies on prompt diagnosis, and specific and immediate treatment of the lifethreatening symptoms. Since patients suffering from OP poisoning can secondarily expose care providers via contaminated skin, clothing, hair, or body fluids. EMS and hospital caregivers should be prepared to protect themselves with appropriate protective equipment, isolate such patients, and decontaminate them. After prompt decontamination, the initial priority of patient management is an immediate ABCDE (A : airway, B : breathing, C : circulation, D : dysfunction or disability of the central nervous system, and E : exposure) resuscitation approach, including aggressive respiratory support, since respiratory failure is the usual ultimate cause of death. The subsequent priority is initiating atropine therapy to oppose the muscarinic symptoms and diazepam to prevent or control seizures, with oximes added to enhance acetylcholinesterase (AChE) activity recovery. Large doses of atropine and oximes may be necessary for poisoning due to suicidal ingestions of OP pesticides.
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This paper investigates the contribution of monetary policy to the changes in outputgrowth and inflation dynamics in the US. We identify a policy shock and a policy rule ina time-varying coefficients VAR using robust sign restrictions. The transmission of policyshocks has been relatively stable. The variance of the policy shock has decreased over time,but policy shocks account for a small fraction of the level and of the variations in inflationand output growth volatility and persistence. We find little evidence of a significant increasein the long run response of the interest rate to inflation. A more aggressive inflation policyin the 1970s would have produced large output growth costs.