943 resultados para Stickhandling and Puck Control
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Vitamin D deficiency is associated with higher cardiovascular risk and metabolic syndrome (MeS) criteria. The main objective of this study was to analyse the association of 25-hydroxyvitamin D (25-OHD) serum levels with MeS (National Cholesterol Education Program-Adult Treatment Panel-III criteria) in 46 Spanish patients with psoriasis, but without arthritis and systemic treatment, and 46 control subjects, matched by sex and age. The patients with psoriasis showed significantly lower level of 25-OHD than controls (30.5 vs. 38.3 ng/ml; p = 0.0001). Patients with MeS had significantly lower serum levels of 25-OHD than those without MeS (24.1 ± 7.5 vs. 32.8 ± 8.9, p = 0.007), and a negative correlation was found between 25-OHD and waist circumference, diastolic blood pressure, fasting glucose, and triglyceridaemia. In the control group no significant correlation between 25-OHD and MeS was found. Al-though the sample was small, our results suggest a potential protective role for 25-OHD in the metabolic profile of patients with psoriasis without arthritis.
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The main objective of this ex post facto study is to compare the differencesin cognitive functions and their relation to schizotypal personality traits between agroup of unaffected parents of schizophrenic patients and a control group. A total of 52unaffected biological parents of schizophrenic patients and 52 unaffected parents ofunaffected subjects were assessed in measures of attention (Continuous PerformanceTest- Identical Pairs Version, CPT-IP), memory and verbal learning (California VerbalLearning Test, CVLT) as well as schizotypal personality traits (Oxford-Liverpool Inventoryof Feelings and Experiences, O-LIFE). The parents of the patients with schizophreniadiffer from the parents of the control group in omission errors on the ContinuousPerformance Test- Identical Pairs, on a measure of recall and on two contrast measuresof the California Verbal Learning Test. The associations between neuropsychologicalvariables and schizotpyal traits are of a low magnitude. There is no defined pattern ofthe relationship between cognitive measures and schizotypal traits
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Si les rôles fonctionnels de diverses cellules immunitaires infiltrant des tissus enflammés sont assez bien compris, par contre, étonnamment, on connaît bien moins la capacité des cellules non hématopoïétiques résidant dans des tissus, à moduler l'activité biologique des cellules immunitaires immigrantes, et donc le résultat de la réponse immunitaire. La présentation des antigènes, dans le contexte des molécules du CMH de classe II (CMHII) à la surface des cellules présentatrices d'antigènes (CPA) professionnelles à une sous- population de lymphocytes T, est cruciale pour le développement des réponses immunitaires protectives spécifiques de l'antigène. En général, l'expression de CMHII est réservée aux CPAs. Toutefois, au cours des pathologies inflammatoires spécifiques d'organe, telles que l'auto-immunité ou la maladie inflammatoire de l'intestin, l'expression de CMHII est également induite par la cytokine interféron (IFN)-y sur des cellules non hématopoïétiques qui résident dans des tissus enflammés. Les conséquences de ce phénomène sont encore peu comprises. Dans cette étude, nous avons utilisé une souche de souris génétiquement modifiées, qui n'a pas la capacité d'induire l'expression de CMHII sur les cellules non hématopoïétiques, mais a maintenu la régulation normale d'expression de CMHII sur les cellules hématopoïétiques. Nous avons appliqué ces souris à différents modèles d'inflammation intestinale et à un modèle de maladie qui imite la maladie auto-immune de l'inflammation du muscle cardiaque (myocardite) chez l'homme. Nous avons pu montrer que, au cours de l'inflammation intestinale, l'expression du CMHII nonhématopoïétique, ou encore l'expression du CMHII par les cellules épithéliales de l'intestin, confère une protection contre la maladie, en réduisant les cellules immunitaires inflammatoires et en augmentant les cellules Τ régulatrices anti-inflammatoires. Ces résultats pourraient expliquer l'échec des traitements d'anti-IFN-γ dans les maladies intestinales inflammatoires chez l'homme. En revanche, dans la myocardite auto-immune, nos résultats indiquent que la présentation d'antigènes par les cellules non hématopoïétiques du coeur est nécessaire pour l'apparition de la pathologie cardiaque, comme nos souris sont résistantes à la maladie. Toutefois, cela n'est pas dû à un défaut d'activation des lymphocytes T, car les lymphocytes Τ des souris mutantes sont parfaitement capables de promouvoir la maladie après le transfert adoptif dans des animaux de type naturel. Nos résultats suggèrent que, durant les maladies inflammatoires spécifiques d'organe, la présentation d'antigène par des cellules non hématopoïétiques module et contribue au résultat de la réponse immunitaire d'une manière opposée, conférant soit la protection contre la maladie ou sa promotion. Nos résultats pourraient ouvrir la voie à des thérapies qui prennent en compte la contribution de la présentation d'antigènes par les cellules non hématopoïétiques, au cours des maladies inflammatoires spécifiques d'organe. - Les molécules du CMH de classe II (CMHII) sont fondamentales pour la présentation des antigènes aux lymphocytes Τ CD4+, car elles permettent le développement des réponses immunitaires spécifiques de l'antigène. Il est largement admis que l'expression de CMHII est réservée aux cellules présentatrices d'antigènes (CPA). Cependant, dans des conditions inflammatoires, l'expression de CMHII est en principe également induite par l'interféron (IFN)-y sur les cellules non hématopoïétiques, telles que les cellules épithéliales et les cardiomyocytes. Une controverse existe jusqu'à présent au sujet de la fonction de cette présentation d'antigènes non professionnelle, pour savoir si elle favorise la tolérance ou l'immunité dépendante des lymphocytes Τ in vivo. Pour répondre à cette question, nous avons testé des souris qui ne sont pas capables d'induire l'expression du CMHII sur les cellules non hématopoïétiques (souris PIV-/- K14 CIITA Tg) parmi différents modèles murins de pathologies inflammatoires, à savoir les modèles de vaccination pour induire des réponses spécifiques d'antigènes des lymphocytes B, plusieurs modèles de colite et un modèle de myocardite auto-immune expérimental (EAM). Pour cela, nous avons administré à ces souris un modèle de colite atténuée, induite par une infection chronique à Helicobacter hepaticus et par l'administration d'anticorps monoclonaux bloquant le récepteur de l'interleukine (IL)-10 (anti-IL-10R). Dans ce système, nous avons pu observer que l'expression abrogée de CMHII a aggravé la colite bactérienne, soit par les cellules non hématopoïétiques, soit exclusivement par les cellules épithéliales intestinales (CEI) dans un autre modèle murin (souris plV_fl/fl vil-Cre Tg). Ce phénotype du côlon a été associé à une augmentation des fréquences de cellules immunitaires innées, de lymphocytes Th1 CD4+, et d'expression des cytokines et de chimiokines pro-inflammatoires, y compris l'IFN-γ. Notamment, l'expression défectueuse de CMHII non hématopoïétique a également réduit les cellules Τ régulatrices (Treg) Forkhead box P3 (FoxP3)+, sans influencer les fréquences des cellules innées lymphoïdes et des cellules Th17. Ces résultats suggèrent un rôle tolérogène de CEIs CMHII+ qui contribue à l'homéostasie immunitaire intestinale. En revanche, dans le modèle d'EAM, les souris ayant subi une ablation de CMHII non hématopoïétique étaient résistantes à l'induction de la maladie, alors que la progression de la pathologie cardiaque, dans les souris de type naturel ou hétérozygotes, a été accompagnée par une régulation positive de l'expression de CMHII du myocarde. Cependant, l'inflammation cardiaque pourrait être transférée de manière adoptive depuis des souris amorcées PIV-/- K14 CIITA Tg vers des souris de type naturel, indiquant l'absence de défaut intrinsèque d'amorçage des cellules T CD4+ dans notre modèle de souris. Ces observations impliquent un rôle à jouer pour des cellules CMHII+ non hématopoïétiques résidentes du coeur, dans la promotion active de ΙΈΑΜ. En conclusion, nos résultats, provenant de diverses pathologies inflammatoires spécifiques d'organes, suggèrent un rôle complexe et divergent, soit tolérogène, soit immunogène/ pathologique, pour l'expression de CMHII non hématopoïétique au cours des pathologies inflammatoires. L'expression non professionnelle de CMHII semble influencer le résultat des réponses immunitaires en fonction de différents facteurs, tels que le tissu cible, le(s) type(s) de cellule(s) non hématopoïétique(s) participante(s) et l'origine de l'inflammation. Nos résultats pourraient potentiellement ouvrir la voie à des applications thérapeutiques, qui tiennent compte de la contribution de la présentation d'antigènes par des CPAs non professionnelles, au cours de l'inflammation spécifique d'organe. - MHC class II (MHCII) molecules are fundamental for the presentation of antigens to CD4+ Τ cells, allowing the development of antigen-specific immune responses. It is widely accepted that MHCII expression is restricted to antigen-presenting cells (APC). However, under inflammatory conditions, MHCII expression is typically also induced by interferon (IFN)-y on nonhematopoietic cells such as epithelial cells and cardiomyocytes. So far, it remains controversial whether this nonprofessional antigen-presentation function promotes CD4+ Τ cell-dependent tolerance or immunity in vivo. To address this issue, we utilised mice which lack inducible MHCII expression on nonhematopoietic cells (pIV-/- K14 CIITA Tg mice) in different mouse models of inflammatory pathologies, namely immunisation models to induce antigen-specific Β cell responses, various colitis models and a model of experimental autoimmune myocarditis (EAM). In an attenuated model of colitis induced by chronic Helicobacter hepaticus infection and treatment with anti-interleukin (IL)-10 receptor (anti-IL-10R) monoclonal blocking antibody, we observed that abrogated MHCII expression by nonhematopoietic cells or, in an alternative tamoxifen-inducible mouse model (plV_fl/fl vil-Cre Tg mice), exclusively by intestinal epithelial cells (IEC), exacerbated bacterial-driven colitis, which was associated with increased colonic frequencies of innate immune cells, CD4+ Th1 cells and expression of proinflammatory cytokines and chemokines, including IFN-γ. Notably, defective nonhematopoietic MHCII expression also resulted in reduced Forkhead box P3 (FoxP3)+ regulatory Τ (Treg) cells without influencing innate lymphoid cell (ILC) and Th17 cell frequencies. These findings suggest a tolerogenic role of MHClT lECs to contribute to intestinal immune homeostasis. In contrast, in the EAM model, mice ablated of nonhematopoietic MHCII were resistant to disease induction, whereas progression of cardiac pathology in WT and heterozygous control mice was accompanied by upregulation of myocardial MHCII expression. However, cardiac inflammation could be adoptively transferred from primed pIV-/- K14 CIITA Tg mice into WT mice, indicating no intrinsic defect of CD4+ Τ activation in our mouse model. These observations imply a role for MHCIT heart-resident nonhematopoietic cells in actively promoting EAM. In conclusion, our findings from different organ-specific inflammatory pathologies suggest a complex and diverging role - either tolerogenic or immunogenic/ pathologic - for nonhematopoietic MHCII expression during inflammatory pathologies: Nonprofessional MHCII expression appears to influence the outcome of immune responses depending on 7 factors such as the target tissue, participating non hematopoietic cell type(s) and the origin of inflammation. Our findings may potentially open the way to therapeutic applications taking into account the contribution of antigen presentation by nonprofessional, tissue-resident APCs during organ-specific inflammation.
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BACKGROUND Lower limb amputees exhibit postural control deficits during standing which can affect their walking ability. OBJECTIVES The primary purpose of the present study was to analyze the thorax, pelvis, and hip kinematics and the hip internal moment in the frontal plane during gait in subjects with Unilateral Transtibial Amputation (UTA). METHOD The participants included 25 people with UTA and 25 non-amputees as control subjects. Gait analysis was performed using the Vicon(r) Motion System. We analyzed the motion of the thorax, pelvis, and hip (kinematics) as well as the hip internal moment in the frontal plane. RESULTS The second peak of the hip abductor moment was significantly lower on the prosthetic side than on the sound side (p=.01) and the control side (right: p=.01; left: p=.01). During middle stance, the opposite side of the pelvis was higher on the prosthetic side compared to the control side (right: p=.01: left: p=.01). CONCLUSIONS The joint internal moment at the hip in the frontal plane was lower on the prosthetic side than on the sound side or the control side. Thorax and pelvis kinematics were altered during the stance phase on the prosthetic side, presumably because there are mechanisms which affect postural control during walking.
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Malaria has always been an important public health problem in Brazil. The early history of Brazilian malaria and its control was powered by colonisation by Europeans and the forced relocation of Africans as slaves. Internal migration brought malaria to many regions in Brazil where, given suitableAnopheles mosquito vectors, it thrived. Almost from the start, officials recognised the problem malaria presented to economic development, but early control efforts were hampered by still developing public health control and ignorance of the underlying biology and ecology of malaria. Multiple regional and national malaria control efforts have been attempted with varying success. At present, the Amazon Basin accounts for 99% of Brazil’s reported malaria cases with regional increases in incidence often associated with large scale public works or migration. Here, we provide an exhaustive summary of primary literature in English, Spanish and Portuguese regarding Brazilian malaria control. Our goal was not to interpret the history of Brazilian malaria control from a particular political or theoretical perspective, but rather to provide a straightforward, chronological narrative of the events that have transpired in Brazil over the past 200 years and identify common themes.
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Paracoccidioidomycosis (PCM) is caused by dimorphic fungi from theParacoccidioides brasiliensis complex. Previous studies have demonstrated that the severity of disease is associated with a T-helper 2 immune response characterised by high interleukin (IL)-4 production. In the present study we analysed two polymorphisms in the IL-4gene (-590 C/T and intron-3 microsatellite) in 76 patients with PCM and 73 control subjects from an endemic area. The production of IL-4 by peripheral blood mononuclear cells after antigen or phytohaemagglutinin stimulation was determined by ELISA. A significant correlation was observed between the RP2/RP2 intron-3 genotype and infection with Paracoccidioides sp.(p = 0.011), whereas the RP1/RP1 genotype was correlated with resistance. No significant correlation was observed for the IL-4promoter polymorphism. Furthermore, the low IL-4 expression observed in the control group compared with patients was associated with the RP1/RP1 genotype. These results suggest that IL-4polymorphisms might be associated with the ability of the host to control Paracoccidioides sp.infection. The relevance of this polymorphism is supported by the observation that patients with disease produce high levels of IL-4 following mitogen or antigen stimulation. The IL-4gene is located in the cytokine cluster region of chromosome 5 where other polymorphisms have also been described.
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BACKGROUND The combined inhibition of BRAF and MEK is hypothesized to improve clinical outcomes in patients with melanoma by preventing or delaying the onset of resistance observed with BRAF inhibitors alone. This randomized phase 3 study evaluated the combination of the BRAF inhibitor vemurafenib and the MEK inhibitor cobimetinib. METHODS We randomly assigned 495 patients with previously untreated unresectable locally advanced or metastatic BRAF V600 mutation-positive melanoma to receive vemurafenib and cobimetinib (combination group) or vemurafenib and placebo (control group). The primary end point was investigator-assessed progression-free survival. RESULTS The median progression-free survival was 9.9 months in the combination group and 6.2 months in the control group (hazard ratio for death or disease progression, 0.51; 95% confidence interval [CI], 0.39 to 0.68; P<0.001). The rate of complete or partial response in the combination group was 68%, as compared with 45% in the control group (P<0.001), including rates of complete response of 10% in the combination group and 4% in the control group. Progression-free survival as assessed by independent review was similar to investigator-assessed progression-free survival. Interim analyses of overall survival showed 9-month survival rates of 81% (95% CI, 75 to 87) in the combination group and 73% (95% CI, 65 to 80) in the control group. Vemurafenib and cobimetinib was associated with a nonsignificantly higher incidence of adverse events of grade 3 or higher, as compared with vemurafenib and placebo (65% vs. 59%), and there was no significant difference in the rate of study-drug discontinuation. The number of secondary cutaneous cancers decreased with the combination therapy. CONCLUSIONS The addition of cobimetinib to vemurafenib was associated with a significant improvement in progression-free survival among patients with BRAF V600-mutated metastatic melanoma, at the cost of some increase in toxicity. (Funded by F. Hoffmann-La Roche/Genentech; coBRIM ClinicalTrials.gov number, NCT01689519.).
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Previously published scientific papers have reported a negative correlation between drinking water hardness and cardiovascular mortality. Some ecologic and case-control studies suggest the protective effect of calcium and magnesium concentration in drinking water. In this article we present an analysis of this protective relationship in 538 municipalities of Comunidad Valenciana (Spain) from 1991-1998. We used the Spanish version of the Rapid Inquiry Facility (RIF) developed under the European Environment and Health Information System (EUROHEIS) research project. The strategy of analysis used in our study conforms to the exploratory nature of the RIF that is used as a tool to obtain quick and flexible insight into epidemiologic surveillance problems. This article describes the use of the RIF to explore possible associations between disease indicators and environmental factors. We used exposure analysis to assess the effect of both protective factors--calcium and magnesium--on mortality from cerebrovascular (ICD-9 430-438) and ischemic heart (ICD-9 410-414) diseases. This study provides statistical evidence of the relationship between mortality from cardiovascular diseases and hardness of drinking water. This relationship is stronger in cerebrovascular disease than in ischemic heart disease, is more pronounced for women than for men, and is more apparent with magnesium than with calcium concentration levels. Nevertheless, the protective nature of these two factors is not clearly established. Our results suggest the possibility of protectiveness but cannot be claimed as conclusive. The weak effects of these covariates make it difficult to separate them from the influence of socioeconomic and environmental factors. We have also performed disease mapping of standardized mortality ratios to detect clusters of municipalities with high risk. Further standardization by levels of calcium and magnesium in drinking water shows changes in the maps when we remove the effect of these covariates.
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The organophosphate temephos has been the main insecticide used against larvae of the dengue and yellow fever mosquito (Aedes aegypti) in Brazil since the mid-1980s. Reports of resistance date back to 1995; however, no systematic reports of widespread temephos resistance have occurred to date. As resistance investigation is paramount for strategic decision-making by health officials, our objective here was to investigate the spatial and temporal spread of temephos resistance in Ae. aegypti in Brazil for the last 12 years using discriminating temephos concentrations and the bioassay protocols of the World Health Organization. The mortality results obtained were subjected to spatial analysis for distance interpolation using semi-variance models to generate maps that depict the spread of temephos resistance in Brazil since 1999. The problem has been expanding. Since 2002-2003, approximately half the country has exhibited mosquito populations resistant to temephos. The frequency of temephos resistance and, likely, control failures, which start when the insecticide mortality level drops below 80%, has increased even further since 2004. Few parts of Brazil are able to achieve the target 80% efficacy threshold by 2010/2011, resulting in a significant risk of control failure by temephos in most of the country. The widespread resistance to temephos in Brazilian Ae. aegypti populations greatly compromise effective mosquito control efforts using this insecticide and indicates the urgent need to identify alternative insecticides aided by the preventive elimination of potential mosquito breeding sites.
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The Mg/Ca and Sr/Ca ratios of living ostracods belonging to 15 different species and sampled monthly over a one year-cycle at five sites (2, 5, 13, 33, and 70 m water depths) in western Lake Geneva (Switzerland) are compared to the oxygen and carbon isotope compositions measured on the same samples as well as to the temperature and chemical composition of the water (δ18OH2O, δ13CDIC, Mg/CaH2O, and Sr/CaH2O) at the time of ostracod calcification. The results indicate that trace element incorporation varied at the species level, mainly because of the ecological and biological differences between the different species (life-cycle, (micro-)habitat preference, biomineralisation processes) and the control thereof on trace element incorporation of the ostracods. In littoral zones, the Mg/Ca and Sr/Ca of ostracod valves increase as temperature and Mg/Ca and Sr/Ca of water increase during spring and summer, hence reflecting mainly seasonal variations. However, given that for Lake Geneva the Mg/Ca and Sr/Ca of water also vary with temperature, it is not possible to distinguish the effects of temperature from those of changes in chemical composition of water on the trace element content in ostracod valves. Results support that both water temperature and water Mg/Ca and Sr/Ca ratios control the final trace element content of Cyprididae valves. In contrast, the trace element content of species living in deeper zones of the basin is influenced by variations in the chemical composition of the pore water for the infaunal species. Trace element content measured for these specimens cannot, therefore, be used to reconstruct the compositions of the water lake bottom. In addition, incorporation of Mg and Sr into the shell differs from one family, sub-family, or even species to the other. This suggests that the distinctive Mg and Sr partition coefcients for the analysed taxa result from different valve calcification strategies that may be phylogenetic.
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The study provides a systematic review that explores the current literature on olfactory capacity in abnormal eating behavior. The objective is to present a basis for discussion on whether research in olfaction in eating disorders may offer additional insight with regard to the complex etiopathology of eating disorders (ED) and abnormal eating behaviors. Electronic databases (Medline, PsycINFO, PubMed, Science Direct, and Web of Science) were searched using the components in relation to olfaction and combining them with the components related to abnormal eating behavior. Out of 1352 articles, titles were first excluded by title (n = 64) and then by abstract and fulltext resulting in a final selection of 14 articles (820 patients and 385 control participants) for this review. The highest number of existing literature on olfaction in ED were carried out with AN patients (78.6%) followed by BN patients (35.7%) and obese individuals (14.3%). Most studies were only conducted on females. The general findings support that olfaction is altered in AN and in obesity and indicates toward there being little to no difference in olfactory capacity between BN patients and the general population. Due to the limited number of studies and heterogeneity this review stresses on the importance of more research on olfaction and abnormal eating behavior.
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BACKGROUND The combined inhibition of BRAF and MEK is hypothesized to improve clinical outcomes in patients with melanoma by preventing or delaying the onset of resistance observed with BRAF inhibitors alone. This randomized phase 3 study evaluated the combination of the BRAF inhibitor vemurafenib and the MEK inhibitor cobimetinib. METHODS We randomly assigned 495 patients with previously untreated unresectable locally advanced or metastatic BRAF V600 mutation-positive melanoma to receive vemurafenib and cobimetinib (combination group) or vemurafenib and placebo (control group). The primary end point was investigator-assessed progression-free survival. RESULTS The median progression-free survival was 9.9 months in the combination group and 6.2 months in the control group (hazard ratio for death or disease progression, 0.51; 95% confidence interval [CI], 0.39 to 0.68; P<0.001). The rate of complete or partial response in the combination group was 68%, as compared with 45% in the control group (P<0.001), including rates of complete response of 10% in the combination group and 4% in the control group. Progression-free survival as assessed by independent review was similar to investigator-assessed progression-free survival. Interim analyses of overall survival showed 9-month survival rates of 81% (95% CI, 75 to 87) in the combination group and 73% (95% CI, 65 to 80) in the control group. Vemurafenib and cobimetinib was associated with a nonsignificantly higher incidence of adverse events of grade 3 or higher, as compared with vemurafenib and placebo (65% vs. 59%), and there was no significant difference in the rate of study-drug discontinuation. The number of secondary cutaneous cancers decreased with the combination therapy. CONCLUSIONS The addition of cobimetinib to vemurafenib was associated with a significant improvement in progression-free survival among patients with BRAF V600-mutated metastatic melanoma, at the cost of some increase in toxicity. (Funded by F. Hoffmann-La Roche/Genentech; coBRIM ClinicalTrials.gov number, NCT01689519.).
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A través de la historia de la vida, gran parte de los organismos han desarrollado estrategias para responder a un mundo en constante cambio. Hoy en día, las actividades humanas producen cambios ambientales a una velocidad sin precedentes, lo cual se traduce en grandes desafíos para la persistencia de biodiversidad. Esta investigación evalúa las respuesta de los animales a los cambios ambientales enfocándose en la flexibilidad del comportamiento como estrategia adaptativa. En una primera aproximación a una escala evolutiva, se otorgan evidencias del vínculo hasta ahora tenue entre la cognición e historias de vida, entregando un claro apoyo a la relación entre longevidad, vida reproductiva y el tamaño del cerebro en mamíferos. La longevidad es el centro de muchas hipótesis respecto a las ventajas de desarrollar un cerebro grande, como por ejemplo en la hipótesis del buffer cognitivo y las respuestas flexibles frente a nuevos ambientes. En un segundo nivel, se abordan factores extrínsecos e intrínsecos que podrían explicar las diferencias individuales en innovación, un componente clave en la flexibilidad del comportamiento. Por medio de una aproximación experimental, se evalúan potenciales escenarios que podrían conducir a consistentes diferencias individuales en uno de los principales factores subyacentes a la innovación (i.e. la motivación), y el potencial control endocrino sobre estos escenarios. Posteriormente, con el objetivo de evaluar la respuesta de los animales frente a los cambios ambientales actuales, se explora la respuesta de los animales frente a una de las actividades humanas mas disruptivas sobre los ecosistemas, la urbanización. Por medio de un analisis filogenetico comparativo a nivel global en aves se abordan los mecanismos implicados en la perdida de biodiversidad observada en ambientes urbanos. Los resultados entregan evidencias sobre la importancia de procesos de dispersión local junto con el papel clave de los rasgos de historia de vida, pero en un sentido diferente al clasicamente pensado. Finalmente por medio de una revisión bibliográfica se entregan evidencias teóricas y empíricas que respaldan el rol clave de la flexibilidad del comportamiento en confrontar los desafíos de una vida urbana. La integración de estos resultados muestra cómo el pasado evolutivo contribuye a hacer frente a los retos ambientales actuales, y pone de relieve posibles consecuencias ante un planeta más cambiante que nunca.
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In order to understand relationships between executive and structural deficits in the frontal cortex of patients within normal aging or Alzheimer's disease, we studied frontal pathological changes in young and old controls compared to cases with sporadic (AD) or familial Alzheimer's disease (FAD). We performed a semi-automatic computer assisted analysis of the distribution of beta-amyloid (Abeta) deposits revealed by Abeta immunostaining as well as of neurofibrillary tangles (NFT) revealed by Gallyas silver staining in Brodman areas 10 (frontal polar), 12 (ventro-infero-median) and 24 (anterior cingular), using tissue samples from 5 FAD, 6 sporadic AD and 10 control brains. We also performed densitometric measurements of glial fibrillary acidic protein, principal compound of intermediate filaments of astrocytes, and of phosphorylated neurofilament H and M epitopes in areas 10 and 24. All regions studied seem almost completely spared in normal old controls, with only the oldest ones exhibiting a weak percentage of beta-amyloid deposit and hardly any NFT. On the contrary, all AD and FAD cases were severely damaged as shown by statistically significant increased percentages of beta-amyloid deposit, as well as by a high number of NFT. FAD cases (all from the same family) had statistically more beta-amyloid and GFAP than sporadic AD cases in both areas 10 and 24 and statistically more NFT only in area 24. The correlation between the percentage of beta-amyloid and the number of NFT was significant only for area 24. Altogether, these data suggest that the frontal cortex can be spared by AD type lesions in normal aging, but is severely damaged in sporadic and still more in familial Alzheimer's disease. The frontal regions appear to be differentially vulnerable, with area 12 having the less amyloid burden, area 24 the less NFT and area 10 having both more amyloid and more NFT. This pattern of damage in frontal regions may represent a strong neuroanatomical support for the deterioration of attention and cognitive capacities as well as for the presence of emotional and behavioral troubles in AD patients.
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Background: Adenosquamous carcinoma (AC) of the head and neck is a distinct entity first described in 1968. Its natural history is more aggressive than squamous-cell carcinoma. The aim of this study was to assess the clinical profile, patterns of failure, and prognostic factors in patients with AC of the head and neck treated by radiation therapy (RT) with or without chemotherapy (CT).Materials and Methods: Data from 19 patients with stage I (n = 3), II (n = 1), III (n = 4), or IVa (n = 11) AC, treated between 1989 and 2009, were collected in a retrospective multicenter Rare Cancer Network study. Median age was 60 years (range, 48−73). Fifteen patients were male, and 4 female. Risk factors, including perineural invasion, lymphangitis, vascular invasion, positive margins were present in the majority (83%) of the patients. Tumour sites included oral cavity in 4, oropharynx in 4, hypopharynx in 2, larynx in 2, salivary glands in 2, nasal vestibule in 2, maxillary sinus in 2, and nasopharynx in 1 patient. Surgery (S) was performed in all but 5 patients. S alone was performed in only 1 patient, and definitive RT alone in 3 patients. Fifteen patients received combined modality treatment (S+RT in 11, RT+CT in 2, and all of the three modalities in 2 patients). Median RT dose to the primary and to the nodes was 66 Gy (range, 50−72) and 53 Gy (range, 44−66), respectively (1.8−2.0 Gy/fr., 5 fr./week). In 4 patients, the planning treatment volume included the primary tumour site only. Eight patients were treated with 2D RT, 7 with 3D conformal RT, and 2 with intensity-modulated RT.Results: After a median follow-up period of 39 months (range, 9−62), 9 patients developed distant metastases (lung, bone, mediastinum, and liver), 7 presented nodal recurrences, and only 4 had a local relapse at the primary site (all in-field recurrences). At last follow-up, 7 patients were alive without disease, 1 alive with disease, 9 died from progressive disease, and 2 died from intercurrent disease. The 3-year and median overall survival, disease-free survival (DFS), and locoregional control rates were 55% (95% confidence interval [CI]: 32−78%) and 39 months, 34% (95% CI: 12−56%) and 22 months, and 50% (95% CI: 22−78%) and 33 months, respectively. In multivariate analysis (Cox model), DFS was negatively influenced by the presence of extracapsular extension (p = 0.01) and advanced stage (IV versus I−III, p = 0.002).Conclusions: Overall prognosis of locoregionally advanced AC remains poor, and distant metastases and nodal relapse occur in almost half of the cases. However, local control is relatively better, and early stage AC patients had prolonged DFS when treated with combined-modality treatment.