797 resultados para body image, Emotional Stroop, attention, memory, cluster analysis, classification
Resumo:
The emergence of host-races within aphids may constitute an obstacle to pest management by means of plant resistance. There are examples of host-races within cereals aphids, but their occurrence in Rose Grain Aphid, Metopolophium dirhodum (Walker, 1849), has not been reported yet. In this work, RAPD markers were used to assess effects of the hosts and geographic distance on the genetic diversity of M. dirhodum lineages. Twenty-three clones were collected on oats and wheat in twelve localitites of southern Brazil. From twenty-seven primers tested, only four primers showed polymorphisms. Fourteen different genotypes were revealed by cluster analysis. Five genotypes were collected only on wheat; seven only on oats and two were collected in both hosts. Genetic and geographical distances among all clonal lineages were not correlated. Analysis of molecular variance showed that some molecular markers are not randomly distributed among clonal lineages collected on oats and on wheat. These results suggest the existence of host-races within M. dirhodum, which should be further investigated using a combination of ecological and genetic data.
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We propose a method for brain atlas deformation in the presence of large space-occupying tumors, based on an a priori model of lesion growth that assumes radial expansion of the lesion from its starting point. Our approach involves three steps. First, an affine registration brings the atlas and the patient into global correspondence. Then, the seeding of a synthetic tumor into the brain atlas provides a template for the lesion. The last step is the deformation of the seeded atlas, combining a method derived from optical flow principles and a model of lesion growth. Results show that a good registration is performed and that the method can be applied to automatic segmentation of structures and substructures in brains with gross deformation, with important medical applications in neurosurgery, radiosurgery, and radiotherapy.
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We report a 38 year-old patient who had temporoparietal epilepsy and unusual ictal "out of body" experiences that remained undiagnosed for more than ten years, until her admission for a motor seizure of the left hemibody. Out of body episodes were experienced as intense and ecstatic astral journeys. EEG showed a bilateral extension of epileptiform abnormalities to the parietal regions, predominantly on the right side. We discuss the various forms of heautoscopy and their putative mechanisms. We suggest that a disturbance in representing space in independent extrapersonal and personal coordinates might be as crucial as the elusive hypothesis of a body schema disorder. Combined involvement of the parietal neocortex and temporolimbic structures might allow those experiences to gain a subjective vividness which appears to be indissociable from normal conscious experiences.
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Purpose: There is evidence indicating that adolescent females smoke as a way to control weight. The aim of our research is to assess whether daily smoking is a marker for weight control practices among adolescent females. Methods: Data were drawn from the 2002 Swiss Multicenter Adolescent Survey on Health (SMASH02) data base, a survey including 7,548 [3,838 females] in-school adolescents aged 16-20 years in Switzerland. Among females self-reporting BMI (N _ 3,761), two groups were drawn: daily smokers (DS, N _ 1,273) included all those smoking at least 1 cigarette/day and never smokers (NS, N _ 1,888) included all those having never smoked. Former (N _ 177) and occasional (N _ 423) smokers were not included. Groups were compared on weight control practices (being on a diet, self-induced vomiting, use of doctor-prescribed or over-the-counter appetite suppressors) controlling for possible confounding variables (age, BMI, feeling fat, body image, use of other substances, depression, sport practice, academic track and perceived advanced puberty). Analyses were performed with STATA 9. Bivariate analyses are presented as point-prevalence and multivariate analysis (using logistic regression) are presented as adjusted odds ratio (AOR) and [95% confidence interval]. Results: In the bivariate analysis, DS females were significantly more likely (p _ 0.001) than NS to be on a diet (DS: 33.2%, NS: 22.2%), to self-induce vomiting (DS: 9.0%, NS: 3.3%), and to use doctor prescribed (DS: 2.3%, NS: 0.9%) or over-the-counter (DS: 3.2%, NS: 1.2%) appetite suppressors. In the multivariate analysis, DS females were more likely than NS to be on a diet (AOR: 1.40 [1.17/1.68]), to self-induce vomiting (AOR: 2.07 [1.45/2.97]), and to use doctor-prescribed appetite suppressors (AOR: 1.99 [1.00/ 3.96]). Conclusions: Weight control practices are more frequent among female daily smokers than among never smokers. This finding seems to confirm cigarette smoking as a way to control weight among adolescent females. Health professionals should inquire adolescent female smokers about weight control practices, and this association must be kept in mind when discussing tobacco cessation options with adolescent females. Sources of Support: The SMASH02 survey was funded by the Swiss Federal Office of Public Health and the participating cantons.
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PURPOSE: To develop and assess the diagnostic performance of a three-dimensional (3D) whole-body T1-weighted magnetic resonance (MR) imaging pulse sequence at 3.0 T for bone and node staging in patients with prostate cancer. MATERIALS AND METHODS This prospective study was approved by the institutional ethics committee; informed consent was obtained from all patients. Thirty patients with prostate cancer at high risk for metastases underwent whole-body 3D T1-weighted imaging in addition to the routine MR imaging protocol for node and/or bone metastasis screening, which included coronal two-dimensional (2D) whole-body T1-weighted MR imaging, sagittal proton-density fat-saturated (PDFS) imaging of the spine, and whole-body diffusion-weighted MR imaging. Two observers read the 2D and 3D images separately in a blinded manner for bone and node screening. Images were read in random order. The consensus review of MR images and the findings at prospective clinical and MR imaging follow-up at 6 months were used as the standard of reference. The interobserver agreement and diagnostic performance of each sequence were assessed on per-patient and per-lesion bases. RESULTS: The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were significantly higher with whole-body 3D T1-weighted imaging than with whole-body 2D T1-weighted imaging regardless of the reference region (bone or fat) and lesion location (bone or node) (P < .003 for all). For node metastasis, diagnostic performance (area under the receiver operating characteristic curve) was higher for whole-body 3D T1-weighted imaging (per-patient analysis; observer 1: P < .001 for 2D T1-weighted imaging vs 3D T1-weighted imaging, P = .006 for 2D T1-weighted imaging + PDFS imaging vs 3D T1-weighted imaging; observer 2: P = .006 for 2D T1-weighted imaging vs 3D T1-weighted imaging, P = .006 for 2D T1-weighted imaging + PDFS imaging vs 3D T1-weighted imaging), as was sensitivity (per-lesion analysis; observer 1: P < .001 for 2D T1-weighted imaging vs 3D T1-weighted imaging, P < .001 for 2D T1-weighted imaging + PDFS imaging vs 3D T1-weighted imaging; observer 2: P < .001 for 2D T1-weighted imaging vs 3D T1-weighted imaging, P < .001 for 2D T1-weighted imaging + PDFS imaging vs 3D T1-weighted imaging). CONCLUSION: Whole-body MR imaging is feasible with a 3D T1-weighted sequence and provides better SNR and CNR compared with 2D sequences, with a diagnostic performance that is as good or better for the detection of bone metastases and better for the detection of lymph node metastases.
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The spatial variability of soil and plant properties exerts great influence on the yeld of agricultural crops. This study analyzed the spatial variability of the fertility of a Humic Rhodic Hapludox with Arabic coffee, using principal component analysis, cluster analysis and geostatistics in combination. The experiment was carried out in an area under Coffea arabica L., variety Catucai 20/15 - 479. The soil was sampled at a depth 0.20 m, at 50 points of a sampling grid. The following chemical properties were determined: P, K+, Ca2+, Mg2+, Na+, S, Al3+, pH, H + Al, SB, t, T, V, m, OM, Na saturation index (SSI), remaining phosphorus (P-rem), and micronutrients (Zn, Fe, Mn, Cu and B). The data were analyzed with descriptive statistics, followed by principal component and cluster analyses. Geostatistics were used to check and quantify the degree of spatial dependence of properties, represented by principal components. The principal component analysis allowed a dimensional reduction of the problem, providing interpretable components, with little information loss. Despite the characteristic information loss of principal component analysis, the combination of this technique with geostatistical analysis was efficient for the quantification and determination of the structure of spatial dependence of soil fertility. In general, the availability of soil mineral nutrients was low and the levels of acidity and exchangeable Al were high.
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One major methodological problem in analysis of sequence data is the determination of costs from which distances between sequences are derived. Although this problem is currently not optimally dealt with in the social sciences, it has some similarity with problems that have been solved in bioinformatics for three decades. In this article, the authors propose an optimization of substitution and deletion/insertion costs based on computational methods. The authors provide an empirical way of determining costs for cases, frequent in the social sciences, in which theory does not clearly promote one cost scheme over another. Using three distinct data sets, the authors tested the distances and cluster solutions produced by the new cost scheme in comparison with solutions based on cost schemes associated with other research strategies. The proposed method performs well compared with other cost-setting strategies, while it alleviates the justification problem of cost schemes.
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INTRODUCTION: Breast cancer subtyping and prognosis have been studied extensively by gene expression profiling, resulting in disparate signatures with little overlap in their constituent genes. Although a previous study demonstrated a prognostic concordance among gene expression signatures, it was limited to only one dataset and did not fully elucidate how the different genes were related to one another nor did it examine the contribution of well-known biological processes of breast cancer tumorigenesis to their prognostic performance. METHOD: To address the above issues and to further validate these initial findings, we performed the largest meta-analysis of publicly available breast cancer gene expression and clinical data, which are comprised of 2,833 breast tumors. Gene coexpression modules of three key biological processes in breast cancer (namely, proliferation, estrogen receptor [ER], and HER2 signaling) were used to dissect the role of constituent genes of nine prognostic signatures. RESULTS: Using a meta-analytical approach, we consolidated the signatures associated with ER signaling, ERBB2 amplification, and proliferation. Previously published expression-based nomenclature of breast cancer 'intrinsic' subtypes can be mapped to the three modules, namely, the ER-/HER2- (basal-like), the HER2+ (HER2-like), and the low- and high-proliferation ER+/HER2- subtypes (luminal A and B). We showed that all nine prognostic signatures exhibited a similar prognostic performance in the entire dataset. Their prognostic abilities are due mostly to the detection of proliferation activity. Although ER- status (basal-like) and ERBB2+ expression status correspond to bad outcome, they seem to act through elevated expression of proliferation genes and thus contain only indirect information about prognosis. Clinical variables measuring the extent of tumor progression, such as tumor size and nodal status, still add independent prognostic information to proliferation genes. CONCLUSION: This meta-analysis unifies various results of previous gene expression studies in breast cancer. It reveals connections between traditional prognostic factors, expression-based subtyping, and prognostic signatures, highlighting the important role of proliferation in breast cancer prognosis.
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We investigate the evolutionary history of the greater white-toothed shrew across its distribution in northern Africa and mainland Europe using sex-specific (mtDNA and Y chromosome) and biparental (X chromosome) markers. All three loci confirm a large divergence between eastern (Tunisia and Sardinia) and western (Morocco and mainland Europe) lineages, and application of a molecular clock to mtDNA divergence estimates indicates a more ancient separation (2.25 M yr ago) than described by some previous studies, supporting claims for taxonomic revision. Moroccan ancestry for the mainland European population is inconclusive from phylogenetic trees, but is supported by greater nucleotide diversity and a more ancient population expansion in Morocco than in Europe. Signatures of rapid population expansion in mtDNA, combined with low X and Y chromosome diversity, suggest a single colonization of mainland Europe by a small number of Moroccan shrews >38 K yr ago. This study illustrates that multilocus genetic analyses can facilitate the interpretation of species' evolutionary history but that phylogeographic inference using X and Y chromosomes is restricted by low levels of observed polymorphism.
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The present study tested the effect of a school-based physical activity (PA) program on quality of life (QoL) in 540 elementary school children. First and fifth graders were randomly assigned to a PA program or a no-PA control condition during one academic year. QoL was assessed by the Child Health Questionnaire at baseline and postintervention. Based on mixed linear model analyses, physical QoL in first graders and physical and psychosocial QoL in fifth graders were not affected by the intervention. In first graders, the PA intervention had a positive impact on psychosocial QoL (effect size [d], 0.32; p < .05). Subpopulation analyses revealed that this effect was caused by an effect in urban (effect size [d], 0.38; p < .05) and overweight first graders (effect size [d], 0.45; p < .05). In conclusion, a school-based PA intervention had little effect on QoL in elementary school children.
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La anorexia nerviosa es un trastorno de la conducta alimentaria que se caracteriza por unapérdida de peso superior al saludablemente recomendado, conductas para perder peso y evitarel aumento de peso, miedo a la obesidad y distorsión de la imagen corporal. Tanto la incidenciacomo la prevalencia de este tipo de trastornos ha aumentado considerablemente en las últimasdécadas, son varios los estudios que afirman que hay una estrecha relación entre la influencia delos factores socioculturales y el grado de distorsión de la imagen corporal en este tipo depacientes.El objetivo de este estudio es analizar la influencia que ejercen los medios de comunicación ylos grupos sociales en la distorsión de la imagen corporal de pacientes con anorexia nerviosa.Para lograr este objetivo se realizará un estudio fenomenológico con pacientes de 16 a 21 añosque se visiten en un hospital de día de trastornos de la conducta alimentaria. Los datos serecogerán mediante de una entrevista semiestructurada basada en los ítems del cuestionario deinfluencia de los modelos estéticos corporales (CIMEC). El análisis de los datos obtenidos serápor edición, transcribiendo la entrevista, identificando los segmentos significativos paraposteriormente poderlos analizar.En relación con las consideraciones finales, es un estudio que dentro de la subjetividad podríaser realmente útil para conocer desde el punto de vista del paciente cómo influyen los medios decomunicación y las relaciones sociales en la anorexia nerviosa, permitiendo la propuesta deacciones futuras que ayuden a estos adolescentes y adultos jóvenes a hacer frente a la presiónque ejerce la sociedad.
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En la actual concepción bio-psico-social, los Trastornos del Comportamiento Alimentario (TCA) y la obesidad están plurideterminados por factores biológicos, psicológicos y socioculturales que actúan como elementos perpetuantes en el tiempo. Se pueden modificar actitudes contraproducentes con un programa de prevención multidisciplinar y disminuir de modo significativo la población con riesgo de obesidad y de padecer un TCA. Para ello, es necesario desarrollar dichos programas de prevención, previos a la atención primaria, y la estrategia para lograrlo es la intervención ante factores de riesgo, integrada en un conjunto de actividades de educación para la salud más global. Esta propuesta educativa pretende brindar a los profesores de Educación Física una revisión bibliográfica sobre la dimensión que desde la cultura occidental se tiene de los Trastornos del Comportamiento Alimentario (TCA) y la obesidad, al tiempo que promueve la reflexión sobre las posibilidades de intervención que ofrece la Educación Física desde el ámbito educativo en cuanto a la prevención de la obesidad, de los TCA, y de las conductas de riesgo. La presente propuesta de proyecto de prevención quiere destacar la función que cumplen docentes, tutores y tutoras, como acompañantes de los estudiantes, su posición privilegiada para conocerlos de cerca y estar así atentos a sus vivencias y la posibilidad de identificar oportunamente conductas no saludables en estudiantes que necesiten ciertas pautas para mejorar su estilo de vida, modificar sus habitos, o ser derivados para una atención especializada. Por ese motivo, en esta propuesta educativa se invita a los docentes y tutores a revisar sus convicciones personales y cuestionar la manera de pensar sobre la belleza física y el cuidado corporal. Esta reflexión junto a las pautas metodológicas permitirá abordar el tema de los TCA y la obesidad con tacto, respeto y la atención necesaria frente a los sentimientos de los y las estudiantes que se encuentran en un periodo de cambios importantes y con interrogantes en torno a su identidad e imagen corporal
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The study of transcriptional regulation often needs the integration of diverse yet independent data. In the present work, sequence conservation, predic-tion of transcription factor binding sites (TFBS) and gene expression analysis have been applied to the detection of putative transcription factor (TF) modules in the regulatory region of the FGFR3 oncogene. Several TFs with conserved binding sites in the FGFR3 regulatory region have shown high positive or negative corre-lation with FGFR3 expression both in urothelial carcinoma and in benign nevi. By means of conserved TF cluster analysis, two different TF modules have been iden-tified in the promoter and first intron of FGFR3 gene. These modules contain acti-vating AP2, E2F, E47 and SP1 binding sites plus motifs for EGR with possible repressor function.
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RESUME OBJECTIF: Outre la stimulation de la sécrétion d'hormone de croissance, la ghréline cause une prise pondérale par augmentation de l'assimilation d'aliments et réduction de la consommation lipidique. Il a été décrit que les taux de ghréline augmentent durant la phase pré-prandiale et diminuent juste après un repas, ceci suggérant qu'elle puisse jouer un rôle d'initiateur de la prise du repas. Cependant, la sécrétion de ghréline chez des sujets à jeun n'a pas encore été étudiée en détail. DESSIN: Les profils de sécrétion de ghréline pendant 24 heures ont été étudiés chez six sujets volontaires sains (3 femmes, 3 hommes; 25.5 ans; BMI 22.8 kg/m2) et comparés aux profils plasmatiques de l'hormone de croissance, de l'insuline et du glucose. METHODE: Des échantillons sanguins ont été prélevés toutes les 20 minutes pendant 24 heures et les taux de ghréline ont été mesurés par radio-immuno essai, utilisant un anticorps polyclonal de lapin. Le profil circadien de la sécrétion de ghréline (cluster analysis) a été évalué. RESULTATS: Une augmentation puis une diminution spontanée des taux de ghréline ont été observées aux moments où les sujets auraient habituellement mangé. La ghréline a été sécrétée de façon pulsatile avec approximativement 8 pics par 24 heures. Une diminution générale des taux de ghréline a également été observée durant la période d'étude. Aucune corrélation n'a pu être observée entre les taux de ghréline, d'homione de croissance, d'insuline et de glucose. CONCLUSIONS: Cette étude montre que pendant une période de jeûne les taux de ghréline suivent un profil similaire à ceux décrits chez des sujets mangeant 3 fois par jour. Durant le jeûne, l'hormone de croissance, l'insuline et le glucose ne semblent pas être impliqués dans la régulation de la sécrétion de ghréline. En outre, nous avons observé que la sécrétion de ghréline est pulsatile. La variation des taux de ghréline, indépendamment des repas, chez des sujets à jeun, renforce les observations préalables selon lesquelles le système nerveux central est primairement impliqué dans la régulation de la prise alimentaire. ABSTRACT: OBJECTIVE: Ghrelin stimulates GH release and causes weight gain through increased food intake and reduced fat utiIization. Ghrelin levels were shown to rise in the preprandial period and decrease shortly after meal consumption, suggesting a role as a possible meal initiator. However, ghrelin secretion in fasting subjects has not yet been studied in detail. DESIGN: 24-h ghrelin profiles were studied in six healthy volunteers (three females; 25.5 years; body mass index 22.8 kg/m2) and compared with GH, insulin and glucose levels. METHODS: Blood samples were taken every 20 min during a 24-h fasting period and total ghrelin levels were measured by RIA using a polyclonal rabbit antibody. The circadian pattern of ghrelin secretion and pulsatility (Cluster analysis) were evaluated. RESULTS: An increase and spontaneous decrease in ghrelin were seen at the timepoints of customary meals. Ghrelin was secreted in a pulsatile manner with approximately 8 peaks/24 h. An overall decrease in ghrelin levels was observed during the study period. There was no correlation of ghrelin with GH, insulin or blood glucose levels. CONCLUSIONS: This pilot study indicates that fasting ghrelin profiles display a circadian pattern similar to that described in people eating three times per day. In a fasting condition. GH, insulin and glucose do not appear to be involved in ghrelin regulation. In addition, we round that ghrelin is secreted in a pulsatile pattern. The variation in ghrelin independently of meals in fasting subjects supports previous observations that it is the brain that is primarily involved in the regulation of meal initiation.