849 research outputs found

    Is second best good enough? An EEG study on the effects of word expectancy in sentence comprehension

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    Sentence comprehension can be facilitated when readers anticipate the upcoming word. Notwithstanding, it remains uncertain if only the most expected word is anticipated, as postulated by the serial graded hypothesis, or if all probable words are pre-activated, as proposed by the parallel probabilistic hypothesis. To test these contrasting accounts, we compared the processing of expected and unexpected words with second-best words, i.e. the second most expected word in a sentence. The results, from 30 participants, revealed a graded facilitation effect for the expected words, indexed by the N400 mean amplitude, which was the least negative for the most expected words, intermediate for second-best words, and most negative for unexpected words. The Post-N400 Positivity analysis did not reveal any significant effects. The facilitation effect found for the most expected and second-best words suggests that readers can pre-activate multiple candidates during sentence comprehension

    Expectancy changes the self-monitoring of voice identity

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    Self‐voice attribution can become difficult when voice characteristics are ambiguous, but functional magnetic resonance imaging (fMRI) investigations of such ambiguity are sparse. We utilized voice‐morphing (self‐other) to manipulate (un‐)certainty in self‐voice attribution in a button‐press paradigm. This allowed investigating how levels of self‐voice certainty alter brain activation in brain regions monitoring voice identity and unexpected changes in voice playback quality. FMRI results confirmed a self‐voice suppression effect in the right anterior superior temporal gyrus (aSTG) when self‐voice attribution was unambiguous. Although the right inferior frontal gyrus (IFG) was more active during a self‐generated compared to a passively‐heard voice, the putative role of this region in detecting unexpected self‐voice changes during action was demonstrated only when hearing the voice of another speaker and not when attribution was uncertain. Further research on the link between right aSTG and IFG is required and may establish a threshold monitoring voice identity in action. The current results have implications for a better understanding of the altered experience of self‐voice feedback in auditory verbal hallucinations

    Blindness influences emotional authenticity perception in voices: Behavioral and ERP evidence

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    The ability to distinguish spontaneous from volitional emotional expressions is an important social skill. How do blind individuals perceive emotional authenticity? Unlike sighted individuals, they cannot rely on facial and body language cues, relying instead on vocal cues alone. Here, we combined behavioral and ERP measures to investigate authenticity perception in laughter and crying in individuals with early- or late-blindness onset. Early-blind, late-blind, and sighted control participants (n = 17 per group, N = 51) completed authenticity and emotion discrimination tasks while EEG data were recorded. The stimuli consisted of laughs and cries that were either spontaneous or volitional. The ERP analysis focused on the N1, P2, and late positive potential (LPP). Behaviorally, early-blind participants showed intact authenticity perception, but late-blind participants performed worse than controls. There were no group differences in the emotion discrimination task. In brain responses, all groups were sensitive to laughter authenticity at the P2 stage, and to crying authenticity at the early LPP stage. Nevertheless, only early-blind participants were sensitive to crying authenticity at the N1 and middle LPP stages, and to laughter authenticity at the early LPP stage. Furthermore, early-blind and sighted participants were more sensitive than late-blind ones to crying authenticity at the P2 and late LPP stages. Altogether, these findings suggest that early blindness relates to facilitated brain processing of authenticity in voices, both at early sensory and late cognitive-evaluative stages. Late-onset blindness, in contrast, relates to decreased sensitivity to authenticity at behavioral and brain levels

    Childhood obesity and reduction of hours of sleep: results from cross-sectional study

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    Childhood obesity is a prevalent condition in modern societies which can negatively impact people's health during life. Although there are several factors contributing to obesity, sleep duration has been pointed out as an important risk factor. This study, held in the district of Porto, Portugal, aimed to analyze the association between sleep duration and the nutritional status of school-aged children studying in Portugal. 1396 students from 35 and 3 public and private schools, respectively, were contacted, of which 829 participated in this study (9.2 +/- 0.38 years old; 50.3% male; 49.7% female). Age, sex, sleep duration, height, weight and body composition were registered trough a questionnaire. According to the obtained z-score for Body Mass Index (BMI), 22.9% of the children were overweight and 15.2% were obese. The mean of sleep duration was 9.7 +/- 1.08 hours and z-score for BMI was 0.78 +/- 1.21, demonstrating a statistically significant (p<0.01) weak negative correlation (r=-0.15) between sleep duration and z-score of BMI. Results were also stratified and analyzed by sex, and the same finding was observed. Therefore, the results suggest a negative association between sleep duration and overweight/obesity in these children. Although more studies are necessary, this finding highlights the need of a global approach which includes sleep assessment and counselling when promoting an appropriate nutritional status

    The role of the cerebellum in adaptation: ALE meta-analyses on sensory feedback error

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    It is widely accepted that unexpected sensory consequences of self-action engage the cerebellum. However, we currently lack consensus on where in the cerebellum, we find fine-grained differentiation to unexpected sensory feedback. This may result from methodological diversity in task-based human neuroimaging studies that experimentally alter the quality of self-generated sensory feedback. We gathered existing studies that manipulated sensory feedback using a variety of methodological approaches and performed activation likelihood estimation (ALE) meta-analyses. Only half of these studies reported cerebellar activation with considerable variation in spatial location. Consequently, ALE analyses did not reveal significantly increased likelihood of activation in the cerebellum despite the broad scientific consensus of the cerebellum's involvement. In light of the high degree of methodological variability in published studies, we tested for statistical dependence between methodological factors that varied across the published studies. Experiments that elicited an adaptive response to continuously altered sensory feedback more frequently reported activation in the cerebellum than those experiments that did not induce adaptation. These findings may explain the surprisingly low rate of significant cerebellar activation across brain imaging studies investigating unexpected sensory feedback. Furthermore, limitations of functional magnetic resonance imaging to probe the cerebellum could play a role as climbing fiber activity associated with feedback error processing may not be captured by it. We provide methodological recommendations that may guide future studies

    Alopecia areata: a retrospective study of the paediatric dermatology department (2000-2008)

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    INTRODUCTION: Alopecia areata usually presents as patchy, nonscarring hair loss. It seems to be an immune mediated disease, whereas genetic predisposition, environmental and psychological triggers may be involved in its aetiology. OBJECTIVES: To study the epidemiology, clinical aspects, associations, and treatment of alopecia areata in the paediatric population of Peadiatric Dermatology outpatients over a 9-year period. Some psychologic characteristics were also assessed. METHODS: Descriptive and retrospective study of all newly diagnosed AA cases seen from January 2000 to December 2008 at the Hospital de SĂŁo Marcos' Paediatric Dermatology Department. Fifteen patients with AA were interviewed for psycologic evaluation. RESULTS: Forty-eight cases (54% male/46% female) were identified. Mean age at presentation was 7.8 years. Family history of AA was reported in 10% of the cases, and in 25% there was a personal and/or family history of atopy. The majority of patients (82%) had mild disease and topical corticotherapy was the first-line treatment for limited AA. Fifty-four percent of these patients had a complete resolution of the lesions with treatment. Systemic treatment (corticosteroids and/or ciclosporin) was used in 71% of patients with extensive disease (more than 50% hair loss). Only one of these patients had a sustained clinical improvement after treatment. Twelve out of 15 respondents (80%) recalled stressful events preceding hair loss. DISCUSSION: Our findings are similar to those reported in other studies. Epidemiologic studies of AA are available in adulthood but there is a paucity of literature on children with AA. A holistic approach is important in the management of childhood AA as the disease can have a severe psychologic impact on an individual's well-being

    Reprogramming energy metabolism and inducing angiogenesis : co-expression of monocarboxylate transporters with VEGF family members in cervical adenocarcinomas

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    Background: Deregulation of cellular energetic metabolism was recently pointed out as a hallmark of cancer cells. This deregulation involves a metabolic reprogramming that leads to a high production of lactate. Lactate efflux, besides contributing for the glycolytic flux, also acts in the extracellular matrix, contributing for cancer malignancy, by, among other effects, induction of angiogenesis. However, studies on the interplay between cancer metabolism and angiogenesis are scarce. Therefore, the aim of the present study was to evaluate the metabolic and vascular molecular profiles of cervical adenocarcinomas, their co-expression, and their relation to the clinical and pathological behavior. Methods: The immunohistochemical expression of metabolism-related proteins (MCT1, MCT4, CD147, GLUT1 and CAIX) as well as VEGF family members (VEGF-A, VEGF-C, VEGF-D, VEGFR-1, VEGFR-2 and VEGFR-3) was assessed in a series of 232 cervical adenocarcinomas. The co-expression among proteins was assessed and the expression profiles were associated with patients’ clinicopathological parameters. Results: Among the metabolism-related proteins, MCT4 and CAIX were the most frequently expressed in cervical adenocarcinomas while CD147 was the less frequently expressed protein. Overall, VEGF family members showed a strong and extended expression with VEGF-C and VEGFR-2 as the most frequently expressed and VEGFR-1 as the less expressed member. Co-expression of MCT isoforms with VEGF family members was demonstrated. Finally, MCT4 was associated with parametrial invasion and HPV18 infection, CD147 and GLUT1 with distant metastasis, CAIX with tumor size and HPV18 infection, and VEGFR-1 with local and lymphnode metastasis. Conclusions: The results herein presented provide additional evidence for a crosstalk between deregulating cellular energetics and inducing angiogenesis. Also, the metabolic remodeling and angiogenic switch are relevant to cancer progression and aggressiveness in adenocarcinomas.CP received a post-doctoral fellowship (SFRH/BPD/69479/2010) and FM-S received a doctoral fellowship (SFRH/BD/87139/2012) from FCT (Portuguese Foundation for Science and Technology). This work was supported by the FCT grant ref. PTDC/SAU-FCF/104347/2008, under the scope of "Programa Operacional Tematico Factores de Competitividade" (COMPETE) of "Quadro Comunitario de Apoio III" and co-financed by Fundo Comunitario Europeu FEDER, and also by FAPESP 2008/03232-1

    Monocarboxylate transporter 4 (MCT4) and CD147 overexpression is associated with poor prognosis in prostate cancer

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    BACKGROUND. Monocarboxylate transporters (MCTs) are transmembrane proteins involved in the transport of monocarboxylates across the plasma membrane, which appear to play an important role in solid tumours, however the role of MCTs in prostate cancer is largely unknown.The aim of the present work was to evaluate the clinico-pathological value of monocarboxylate transporters (MCTs) expression, namely MCT1, MCT2 and MCT4, together with CD147 and gp70 as MCT1/4 and MCT2 chaperones, respectively, in prostate carcinoma. METHODS. Prostate tissues were obtained from 171 patients, who performed radical prostatectomy and 14 patients who performed cystoprostatectomy. Samples and clinico-pathological data were retrieved and organized into tissue microarray (TMAs) blocks. Protein expression was evaluated by immunohistochemistry in neoplastic (n= 171), adjacent non-neoplastic tissues (n= 135), PIN lesions (n=40) and normal prostatic tissue (n=14). Protein expression was correlated with patients' clinicopathologic characteristics. RESULTS. In the present study, a significant increase of MCT2 and MCT4 expression in the cytoplasm of tumour cells and a significant decrease in both MCT1 and CD147 expression in prostate tumour cells was observed when compared to normal tissue. All MCT isoforms and CD147 were expressed in PIN lesions. Importantly, for MCT2 and MCT4 the expression levels in PIN lesions were between normal and tumour tissue, which might indicate a role for these MCTs in the malignant transformation. Associations were found between MCT1, MCT4 and CD147 expressions and poor prognosis markers; importantly MCT4 and CD147 overexpression correlated with higher PSA levels, Gleason score and pT stage, as well as with perineural invasion and biochemical recurrence. CONCLUSIONS. Our data provides novel evidence for the involvement of MCTs in prostate cancer. According to our results, we consider that MCT2 should be further explored as tumour marker and both MCT4 and CD147 as markers of poor prognosis in prostate cancer.NPG, CP and VMG received fellowships from the Portuguese Foundation for Science and Technology (FCT), refs. SFRH/BD/61027/2009, SFRH/BPD/69479/ 2010 and SFRH/BI/33503/2008, respectively. This work was supported by the FCT grant ref. PTDC/SAU-FCF/104347/2008, under the scope of Programa Operacional Temático Factores de Competitividade” (COMPETE) of Quadro Comunitário de Apoio III and co-financed by Fundo Comunitário Europeu FEDER
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