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Embora os estudantes universitários tenham fácil acesso à informação sobre a transmissão do VIH e os comportamentos de risco associados à actividade sexual, esta informação nem sempre é correcta nem se baseia em fontes fiáveis ou conhecimentos específicos. Por outro lado, o nível de conhecimentos nem sempre se traduz numa utilização mais frequante do preservativo. Neste estudo analisaram-se as fontes de informação sobre os métodos contraceptivos e as doenças de transmissão sexual, os conhecimentos sobre a AIDS e o modo de transmissão do VIH e o uso de preservativo em 678 estudantes universitários portugueses e espanhóis. O nível de conhecimento é elevado em ambas as amostras, contudo os estudantes portugueses apresentam um melhor nível. Encontraram-se algumas diferenças no uso do preservativo e na utilização das fontes de informação entre países e sexo. Discutem-se as implicações para as actividades de promoção da saúde assim como o papel dos diferentes agentes educativos

Studies addressing the recognition of emotions in blind or deaf participants have been carried out only with children and adolescents. Due to these age limits, such studies do not clarify the long-term effects of vision and hearing disabilities on emotion recognition in adults. We assessed the ability to recognize basic emotions in 15 deaf adults (aged 32.4 ± 8.1 yrs) and in 15 blind adults (48.3 ± 10.5 yrs). Auditory and visual stimuli expressing six basic emotional states were presented to participants ("Florida Affect Battery"). Participants also performed an empathy test. Deaf participants showed difficulties in emotion recognition tasks compared to the typical hearing participants; however, differences were only statistically reliable for Facial Emotion Discrimination and Naming tasks (specifically, naming expressions of fear). Deaf participants also revealed inferior levels of cognitive empathy. Concerning blind participants, their performance was lower than the controls' only when the task required the evaluation of emotional prosody while ignoring the semantic content of the sentence. Overall, although deaf and blind participants performed reasonably well on tasks requiring recognition of basic emotions, sensory loss may hinder their social perception skills when processing subtle emotions or when the extraction of simultaneous prosodic and semantic information is required.

Cardiovascular diseases are the main cause of mortality worldwide, and childhood excess weight/obesity are strong correlators of accumulated risk in later life. A relationship between maternal preeclampsia and offspring's childhood obesity is recognized, but most studies fail to control for strong confounders. Our goal is to analyze the association between preeclampsia and childhood excess weight/obesity, after accounting for important confounders. We recruited 5133 women with singleton pregnancies during admission for delivery. Sixty-seven pregnancies were complicated by preeclampsia. Maternal and children outcomes were assessed at 10 years of age. We analyzed the association between preeclampsia and childhood excess weight/obesity by fitting a linear regression model (using offspring body mass index (BMI) z-score at 10 years of age) and a logistic regression model (using excess weight/obesity status). We then controlled both models for known confounders, namely maternal prepregnancy BMI, parity, and smoking during pregnancy. At 10 years of age, offspring of preeclamptic mothers had a higher BMI z-score and were more likely classified as overweight/obese, but these differences were not statistically significant. After controlling for maternal prepregnancy BMI, parity, and smoking during pregnancy, there was a high magnitude change in the beta coefficient of preeclampsia in the linear (0.175; −0.014) and the logistic regression models (1.48; 1.23) suggesting that the association between preeclampsia and childhood excess weigh/obesity is significantly confounded by these variables. These confounders also showed a significant association with childhood obesity. This finding suggests that in utero exposure to preeclampsia seems to have less impact in childhood obesity than the previously described confounders. [ABSTRACT FROM AUTHOR]

In spite of the advances in knowledge on the multi--factorial nature of obesity, many questions related to the consequences of the disease continue to be unanswered. Several studies have reported biomechanic and kinematic adaptation and alterations in walking and in tasks of every day life, motivated by the additional load of fat mass in children and adults. The main objective of this study was to understand the effect of obesity in the electromyographic activity of four lower extremity muscles during three speeds of walking and during a countermovement jump (CMJ) in twenty two (9 obese and 13 normal weight) female adolescents aged 13. Although electromyographic differences were not observed between groups for normal, slow and fast speeds, data suggests that the preferred pace of the obese is less efficient than that of the normal weight group. In CMJ task, differences in the after--fall jump phase were observed. More studies are needed to explain if the few differences observed between groups are caused by the bigger amount of fat mass. [ABSTRACT FROM AUTHOR]

Summary: Fungal recognition by Dectin‐1 receptor triggers a series of cellular mechanisms involved in a protective activation of the immune system. In this study, we aimed to evaluate the participation of Dectin‐1 receptor in the induction of IL‐8, TNF‐α, IL‐12, IL‐10 and IL‐17A secretion by human monocytes activated with different cytokines, and challenged in vitro with Paracoccidioides brasiliensis (P. brasiliensis). Our results show that monocytes challenged with P. brasiliensis (Pb265) are able to produce IL‐12, IL‐8, IL‐17, IL‐10 and TNF‐α. Dectin‐1 receptor blockage decreased the IL‐12, IL‐17, IL‐10 and TNF‐α levels indicating the participation of such receptor in the induction of these cytokines. Only IL‐8 production was not affected by the blockage. Cells activation with different cytokines showed that GM‐CSF was able to induce secretion of all cytokines and the receptor blockage prior to the challenge also decreased the cytokine secretion, except IL‐8. Monocytes activated with TNF‐α promoted IL‐8, IL‐10 and TNF‐α production, whereas stimulation with IFN‐γ promoted mainly IL‐12 and TNF‐α. Thus, these findings bring new and important knowledge about Dectin‐1 participation in cytokines production by monocytes challenged with Pb265. [ABSTRACT FROM AUTHOR]

Thought suppression increases the persistence of unwanted idiosyncratic worrisome thoughts when individuals try to suppress them. The failure of suppression may contribute to the development and maintenance of emotional disorders. Depressive people seem particularly prone to engage in unsuccessful mental control strategies such as thought suppression. Worry has been reported to be elevated in depressed individuals and a dysphoric mood may also contribute to the failure of suppression. No studies examine, however, the suppression of worrisome thoughts in individuals with depressive symptoms. To investigate the suppression effects of worrisome thoughts, 46 participants were selected according to the cut-off score of a depressive symptomatology scale, and they were divided in two groups (subclinical and nonclinical group). All of the individuals took part in an experimental paradigm of thought suppression. The results of the mixed factorial analysis of variance revealed an increased frequency of worrisome thoughts during the suppression phase, depending on the depressive symptoms. These findings confirm that a depressive mood can reduce the success of suppression. [ABSTRACT FROM AUTHOR]

Background: The mechanisms and triggers of the attentional bias in social anxiety are not yet fully determined, and the modulating role of personality traits is being increasingly acknowledged. Aims: Our main purpose was to test whether social anxiety is associated with mechanisms of hypervigilance, avoidance (static biases), vigilance-avoidance or the maintenance of attention (dynamic biases). Our secondary goal was to explore the role of personality structure in shaping the attention bias. Method: Participants with high vs low social anxiety and different personality structures viewed pairs of faces (free-viewing eye-tracking task) representing different emotions (anger, happiness and neutrality). Their eye movements were registered and analysed for both whole-trial (static) and time-dependent (dynamic) measures. Results: Comparisons between participants with high and low social anxiety levels did not yield evidence of differences in eye-tracking measures for the whole trial (latency of first fixation, first fixation direction, total dwell time), but the two groups differed in the time course of overt attention during the trial (dwell time across three successive time segments): participants with high social anxiety were slower in disengaging their attention from happy faces. Similar results were obtained using a full-sample, regression-based analysis. Conclusion: Our results speak in favour of a maintenance bias in social anxiety. Preliminary results indicated that personality structure may not affect the maintenance (dynamic) bias of socially anxious individuals, although depressive personality structures may favour manifestations of a (static) hypervigilance bias. [ABSTRACT FROM AUTHOR]

BRCA1 and BRCA2 mutations are responsible for hereditary breast and ovarian cancer, but they also confer an increased risk for the development of rarer cancers associated with this syndrome, namely, cancer of the pancreas, male breast, peritoneum, and fallopian tube. The objective of this work was to quantify the contribution of the founder mutations BRCA2 c.156_157insAlu and BRCA1 c.3331_3334del for cancer etiology in unselected hospital-based cohorts of Portuguese patients diagnosed with these rarer cancers, by using a strategy that included testing of archival tumor tissue. A total of 102 male breast, 68 pancreatic and 33 peritoneal/fallopian tube carcinoma cases were included in the study. The BRCA2 c.156_157insAlu mutation was observed with a frequency of 7.8% in male breast cancers, 3.0% in peritoneal/fallopian tube cancers, and 1.6% in pancreatic cancers, with estimated total contributions of germline BRCA2 mutations of 14.3%, 5.5%, and 2.8%, respectively. No carriers of the BRCA1 c.3331_3334del mutation were identified. During our study, a patient with an ampulla of Vater carcinoma was incidentally found to carry the BRCA2 c.156_157insAlu mutation, so we decided to test a consecutive series of additional 15 ampullary carcinomas for BRCA1/BRCA2 mutations using a combination of direct founder mutation testing and full gene analysis with next generation sequencing. BRCA2 mutations were observed with a frequency of 14.3% in ampulla of Vater carcinomas. In conclusion, taking into account the implications for both the individuals and their family members, we recommend that patients with these neoplasias should be offered BRCA1/BRCA2 genetic testing and we here show that it is feasible to test for founder mutations in archival tumor tissue. Furthermore, we identified for the first time a high frequency of germline BRCA2 mutations in ampullary cancers. [ABSTRACT FROM AUTHOR]

Background: Developmental concepts of 'Theory of Mind' (ToM) suggest that this cognitive domain is an innate human capacity requiring input from the social environment to mature. Research suggests substantial individual differences in ToM, depending on childhood experiences, genetics, and the presence or absence of a neuropsychiatric disorder. None of the existing ToM tests for adult populations have been made available in Portuguese. Accordingly, the main objective of this study was to evaluate the psychometric properties of the Portuguese versions of the Faux Pas (FP) Recognition Test and the ToM Picture Stories Task. Sampling and Methods: Both tests were given to a sample of 200 Portuguese adults (125 women and 75 men) aged between 18 and 60 years. Results and Conclusions: The psychometric analyses of the results indicate that the Portuguese version of the FP Recognition Test is appropriate for use in research and clinical settings, providing a composite score that reliably measures the ability to infer the thoughts and feelings of others in a 'faux pas' situation (Cronbach's α = 0.82). However, the ToM Picture Stories Task did not show acceptable psychometric qualities. [ABSTRACT FROM AUTHOR]

Background Multidrug resistance 1 (MDR1) gene encodes for an ATP binding cassette transporter - Pglycoprotein (P-gp) - involved in chemoresistance to taxanes. MDR1 promoter methylation is frequent in prostate carcinoma (PCa), suggesting an epigenetic regulation but no functional correlation has been established. We aimed to elucidate the epigenetic mechanisms involved in MDR1 deregulation in PCa. Results MDR1 promoter methylation and P-gp expression were assessed in 121 PCa, 39 high-grade prostatic intraepithelial neoplasia (HGPIN), 28 benign prostatic hyperplasia (BPH) and 10 morphologically normal prostate tissue (NPT) samples, using quantitative methylation specific PCR and immunohistochemistry, respectively. PCa cell lines were exposed to a DNA methyltransferases inhibitor 5-aza-2'deoxycytidine (DAC) and histone deacetylases inhibitor trichostatin A (TSA). Methylation and histone posttranscriptional modifications status were characterized and correlated with mRNA and protein expression. MDR1 promoter methylation levels and frequency significantly increased from NPTs, to HGPIN and to PCa. Conversely, decreased or absent P-gp immunoexpression was observed in HGPIN and PCa, inversely correlating with methylation levels. Exposure to DAC alone did not alter significantly methylation levels, although increased expression was apparent. However, P-gp mRNA and protein re-expression were higher in cell lines exposed to TSA alone or combined with DAC. Accordingly, histone active marks H3Ac, H3K4me2, H3K4me3, H3K9Ac, and H4Ac were increased at the MDR1 promoter after exposure to TSA alone or combined with DAC. Conclusion Our data suggests that, in prostate carcinogenesis, MDR1 downregulation is mainly due to histone post-translational modifications. This occurs concomitantly with aberrant promoter methylation, substantiating the association with P-gp decreased expression. CpG island hypermethylation, epigenetic regulation, histone post-translational activation/repression marks, MDR1, P-gp, prostate. [ABSTRACT FROM AUTHOR]

We introduce expressible preferential logics, whose preference relations can be defined by some abstract logic. Abstract logics not only allow one to describe preference relations, but also classes of abstract preferential logics and give general proofs for properties common to all logics in these classes. Our approach follows that of Abstract Model Theory. We show that some well-known non-monotonic logics are preferential. We prove that they are elementary, which means that their preference relation can be defined in first-order logic. We study expressiveness and definability results for wide classes of abstract preferential logics in the spirit of Universal Logic. We present a collapse result for expressible preferential logics. We prove that, for a class of expressible preferential logics, if the class of minimal models of a finite set of sentences is Δ-L-expressible, then it is L-expressible, i.e. such class of models can be finitely axiomatized in L. Using this result, we show that under certain conditions one can axiomatize the class ℂ of minimal models of a finite set of sentences where some symbol P is defined using that set and an explicit definition for this symbol. [ABSTRACT FROM AUTHOR]

The notion of the least fixed point of an operator is widely applied in computer science as, for instance, in the context of query languages for relational databases. Some extensions of first-order classical logic (FOL) with fixed point operators, as the least fixed point logic (LFP), were proposed to deal with problems related to the expressivity of FOL. LFP captures the complexity class PTIME over the class of finite ordered structures. The descriptive characterization of computational classes is a central issue within finite model theory (FMT). Trahtenbrot's theorem states that validity over finite models is not recursively enumerable, that is, completeness fails over finite models. This result is based on an underlying assumption that any deductive system is of finite nature. However, we can relax such assumption as done in the scope of proof theory for arithmetic. Motivated by Gödel incompleteness theorems, proof theory for arithmetic offer an example of a true mathematically meaningful principle non-derivable in first-order arithmetic. One way of presenting this proof is based on a definition of a proof system with an infinitary rule, the ω-rule, that establishes the consistency of first-order arithmetic through a proof-theoretical perspective. Inspired in this rule, here we will propose an infinitary natural deduction system, and a sequent calculus version, for FOL and LFP restricted to finite models, FOLfin and LFPfin, respectively, we will prove soundness and completeness for them and also normal form theorems for them. With this infinitary deductive system for LFPfin, we aim to present a proof theory for a logic traditionally investigated within the scope of FMT. It opens up an alternative way of proving results already obtained within FMT and also new ones through a proof-theoretical perspective. [ABSTRACT FROM PUBLISHER]

We investigate some logics which use the concept of minimal models in their definition. Minimal objects are widely used in Logic and Computer Science. They are applied in the context of Inductive Definitions, Logic Programming and Artificial Intelligence. An example of logic which uses this concept is the MIN(FO) logic due to van Benthem [20]. He shows that MIN(FO) is equivalent to the Least Fixed Point logic (LFP) in expressive power. In [6], we extended MIN(FO) to the MIN Logic and proved it is equivalent to second-order logic in expressive power. Here, we exhibit a fragment of MIN, the MINΔ logic, which is more expressive than LFP, less expressive than MIN and closed under boolean connectives and first-order quantification. In order to do this, in the Section 2, we prove that the Downward Löwenheim-Skolem Theorem holds for arbitrary countable sets of LFP-formulas by showing that every infinite structure has a countable LFP-substructure. The method may be used to generalize this theorem to any set of LFP-formulas. We also analyse the expressive power of the Nested Abnormality Theories (NATs) of Lifschitz, another formalism based on minimal models used in Artificial Intelligence, and we demonstrate that for each second-order theory Γ there is a NAT which is a conservative extension of Γ. We give a translation from second-order sentences into such NATs which is linear in the size of the sentence in prenex normal form. Finally, we establish a hierarchy of expressiveness of these logics that deal with the concept of minimal models. [ABSTRACT FROM PUBLISHER]

We review five recent works [1, 2, 9, 15, 16] which present natural deduction systems for linear logic, or for fragments of that logic, and introduce a new single-conclusion natural deduction system for first-order classical linear logic named NDLL. Moreover, we demonstrate the equivalence (in the sense of provability) between the NDLL system and Girard's linear sequent calculus, and prove the weak normalization theorem and its usual companion: the subformula principle for normal deductions in NDLL. [ABSTRACT FROM PUBLISHER]

Background: trastuzumab is considered the standard of care for human epidermal growth factor receptor-2 (HER-2+) breast cancer patients. Regardless of the benefits of its use, many early-stage patients eventually recur, and usually, the disease progresses within a year. Since about half of the HER-2+ patients do not respond to trastuzumab, new biomarkers of prognosis and prediction are warranted to allow a better patient stratification. Annexin A1 (ANXA1) was previously reported to contribute to trastuzumab resistance through AKT activation. An association between adenine thymine-rich interactive domain 1A (ARID1A) loss and ANXA1 upregulation was also previously suggested by others. Methods: in this study, we examined tissue samples from 215 HER-2+ breast cancer patients to investigate the value of ARID1A and ANXA1 protein levels in trastuzumab response prediction and patient outcome. Expression of ARID1A and ANXA1 were assessed by immunohistochemistry. Results: contrary to what was expected, no inverse association was found between ARID1A and ANXA1 expression. HER-2+ (non-luminal) tumours displayed higher ANXA1 expression than luminal B-like (HER-2+) tumours. Concerning trastuzumab resistance, ARID1A and ANXA1 proteins did not demonstrate predictive value as biomarkers. Nevertheless, an association was depicted between ANXA1 expression and breast cancer mortality and relapse. Conclusions: overall, our results suggest that ANXA1 may be a useful prognostic marker in HER-2+ patients. Additionally, its ability to discriminate between HER-2+ (non-luminal) and luminal B-like (HER-2+) patients might assist in patient stratification regarding treatment strategy. [ABSTRACT FROM AUTHOR]