831 resultados para Aggressiveness in adolescence


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A longitudinal study observing cochlear implant recipients' social skills using ratings from their parents and the students themselves over time. The study looked at how adolescents using cochlear implants rate their own social skills compared to an age matched normative group of hearing students, and compared these ratings with social skills ratings obtained from their parents. The study also compared social ratings in adolescence to previous ratings of the same children obtained in elementary school.

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BACKGROUND: Sex differences are present in many neuropsychiatric conditions that affect emotion and approach-avoidance behavior. One potential mechanism underlying such observations is testosterone in early development. Although much is known about the effects of testosterone in adolescence and adulthood, little is known in humans about how testosterone in fetal development influences later neural sensitivity to valenced facial cues and approach-avoidance behavioral tendencies. METHODS: With functional magnetic resonance imaging we scanned 25 8-11-year-old children while viewing happy, fear, neutral, or scrambled faces. Fetal testosterone (FT) was measured via amniotic fluid sampled between 13 and 20 weeks gestation. Behavioral approach-avoidance tendencies were measured via parental report on the Sensitivity to Punishment and Sensitivity to Rewards questionnaire. RESULTS: Increasing FT predicted enhanced selectivity for positive compared with negatively valenced facial cues in reward-related regions such as caudate, putamen, and nucleus accumbens but not the amygdala. Statistical mediation analyses showed that increasing FT predicts increased behavioral approach tendencies by biasing caudate, putamen, and nucleus accumbens but not amygdala to be more responsive to positive compared with negatively valenced cues. In contrast, FT was not predictive of behavioral avoidance tendencies, either through direct or neurally mediated paths. CONCLUSIONS: This work suggests that testosterone in humans acts as a fetal programming mechanism on the reward system and influences behavioral approach tendencies later in life. As a mechanism influencing atypical development, FT might be important across a range of neuropsychiatric conditions that asymmetrically affect the sexes, the reward system, emotion processing, and approach behavior.

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AbstractBackground Depression in adolescence is debilitating with high recurrence in adulthood, yet its pathophysiological mechanism remains enigmatic. To examine the interaction between emotion, cognition and treatment, functional brain responses to sad and happy distractors in an affective go/no-go task were explored before and after Cognitive Behavioural Therapy (CBT) in depressed female adolescents, and healthy participants. Methods Eighty-two Depressed and 24 healthy female adolescents, aged 12 to 17 years, performed a functional magnetic resonance imaging (fMRI) affective go/no-go task at baseline. Participants were instructed to withhold their responses upon seeing happy or sad words. Among these participants, 13 patients had CBT over approximately 30 weeks. These participants and 20 matched controls then repeated the task. Results At baseline, increased activation in response to happy relative to neutral distractors was observed in the orbitofrontal cortex in depressed patients which was normalized after CBT. No significant group differences were found behaviourally or in brain activation in response to sad distractors. Improvements in symptoms (mean: 9.31, 95% CI: 5.35-13.27) were related at trend-level to activation changes in orbitofrontal cortex. Limitations In the follow-up section, a limited number of post-CBT patients were recruited. Conclusions To our knowledge, this is the first fMRI study addressing the effect of CBT in adolescent depression. Although a bias toward negative information is widely accepted as a hallmark of depression, aberrant brain hyperactivity to positive distractors was found and normalised after CBT. Research, assessment and treatment focused on positive stimuli could be a future consideration. Moreover, a pathophysiological mechanism distinct from adult depression may be suggested and awaits further exploration.

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This paper evaluates how information asymmetry affects the strength of competition in credit markets. A theory is presented in which adverse selection softens competition by decreasing the incentives creditors have for competing in the interest rate dimension. In equilibirum, although creditors compete, the outcome is similar to collusion. Three empirical implications arise. First, interest rate should respond asymmetrically to changes in the cost of funds: increases in cost of funds should, on average, have a larger effect on interest rates than decreases. Second, aggressiveness in pricing should be associated with a worseing in the bank level default rates. Third, bank level default rates should be endogenous. We then verify the validity of these three empirical implications using Brazilian data on consumer overdraft loans. The results in this paper rationalize seemingly abnormallly high interest rates in unsecured loans.

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The intensification of the production system in the poultry industry and the vertical integration of the poultry agribusiness have brought profound changes in the physical and social environment of domestic fowls in comparison to their ancestors and have modified the expression of aggression and submission. The present review has covered the studies focusing on the different aspects linked to aggressiveness in the genus Gallus. The evaluated studies have shown that aggressiveness and subordination are complex behavioral expressions that involve genetic differences between breeds, strains and individuals, and differences in the cerebral development during growth, in the hormonal metabolism, in the rearing conditions of individuals, including feed restriction, density, housing type (litter or cage), influence of the opposite sex during the growth period, existence of hostile stimuli (pain and frustration), ability to recognize individuals and social learning. The utilization of fighting birds as experimental material in the study of mechanisms that have influence on the manifestation of aggressiveness in the genus Gallus might comparatively help to elucidate important biological aspects of such behavior.

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Transitional cell carcinoma (TCC) of the bladder is a neoplasm with variability in its clinical behavior. Although there are several studies correlating stage and ABO isoantigen expression with invasiveness, there is no single predictor factor to assess the potential invasiveness, especially in the low grade, non-invasive TCC. In the present study we evaluated the correlation of histological grade plus stage and the expression of beta human chorionic gonadotropin (beta-hCG), in 100 cases of TCC, with the clinical behavior. These features were correlated with tumor progression in patients with at least two years of follow up. We observed more aggressiveness in G4 group (high grade and invasive) (93% had tumor progression) when compared to G1 group (low grade and superficial) (11% had tumor progression). However in 25.5% of the TCC cases (groups G2: low grade and invasive and G3: high grade and superficial) the clinical behavior was intermediate, showing some limitation in using grading and staging only, as a predictive factor. There was an expression of beta-hCG in 21.4% of the cases in up to 25% of the tumor cells without any trophoblastic morphology. These beta-hCG producing TCC had a strong correlation with aggressiveness: 39.1% and 12.8% of the TCC expressed beta-hCG with and without tumor progression, respectively.

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Thirty fine-needle biopsy (FNB) samples from 28 dogs subjected to surgical resection of cutaneous mast cell tumors (MCTs) were stained with Giemsa. At least 100 neoplastic cells from each cytology slide were evaluated by morphometric analysis. The parameters were: area, perimeter of the cell, cytoplasm, nucleus and circumference factor. MCTs of grade III had a mean cellular area of 231.70 μm2 ± 57.1, and grade II had a mean of 252.30 μm2 ± 55.0. Cellular perimeter was 61.20 ± 7.1 in grade II and 59.1 ± 8.6 in grade III. Cellular parameters were not statistically different between grades (p>.05). Mean nuclear area was 88.90 μm2 ± 19 in grade III and 72.30 μm2 ± 13.9 in grade II, with statistical difference between grades (P =.011). Mean nuclear perimeter was 32.40 ìm ± 3.0 in grade II and 35.70 ìm ± 4.0 in grade III, with statistical difference between grades (P =.018). Mean nuclear circumference factor was 1.0 ± 0.33 in grade II and 1.1 ± 0.28 in grade III, with no statistical difference between grades (P = 0.78). Nuclear-tocytoplasmic ratio in grade II was 0.29 ±.07 and 0.39 ±.08 in grade III, with statistical difference (P =.02). The number of binucleated and multinucleated cells and mitotic figures was significantly increased in grade III MCTs (P <.001). In conclusion, the number of mitotic figures, presence of binucleation and multinucleation, and nuclear-to-cytoplasmic ratio can help to guide a profile of MCT aggressiveness in cytologic preparations.

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Urothelial bladder cancer (UBC) is a heterogeneous type of disease. It is urgent to screen biomarkers of tumour aggressiveness in order to clarify the clinical behaviour and to personalize therapy in UBC patients. Raf kinase inhibitory protein (RKIP) is a metastasis suppressor, and its downregulation is associated with metastatic events in an increasing number of solid tumours. We evaluated the clinical and prognostic significance of RKIP expression in patients with high risk of progression UBC. Using immunohistochemistry, we determined RKIP expression levels in a series of 81 patients with high-grade pT1/pTis or muscle-invasive UBC. Staining of CD31 and D2-40 was used to assess blood and lymphatic vessels, in order to distinguish between blood and lymphatic vessel invasion (LVI). We found that 90 % of pT1/pTis tumours, 94 % of non-muscle invasive papillary tumours and 76 % of the cases without LVI occurrence expressed RKIP in >10 % of cells. In this group, we observed a subgroup of tumours (42 %) in which the tumour centre was significantly more intensely stained than the invasion front. This heterogeneous pattern was observed in 63 % of the cases with LVI. Low RKIP expression was associated with poorer 5-year disease-free and overall survival rates, and remained as an independent prognostic factor for disease-free survival. Loss of RKIP expression may be an important prognostic factor for patients with high risk of progression bladder cancer. © 2013 Springer-Verlag Berlin Heidelberg.

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Purpose Mantle-cell lymphoma (MCL) has a variable natural history but is incurable with current therapies. MicroRNAs (miRs) are useful in prognostic assessment of cancer. We determined an miR signature defining aggressiveness in B-cell non-Hodgkin lymphomas (NHL) and assessed whether this signature aids in MCL prognosis.MethodsWe assessed miR expression in a training set of 43 NHL cases. The miR signature was validated in 44 additional cases and examined on a training set of 119 MCL cases from four institutions in Canada. miRs significantly associated with overall survival were examined in an independent cohort of 114 MCL cases to determine association with patient outcome. miR expression was combined with current clinical prognostic factors to develop an enhanced prognostic model in patients with MCL.ResultsFourteen miRs were differentially expressed between aggressive and indolent NHL; 11 of 14 were validated in an independent set of NHL (excluding MCL). miR-127-3p and miR-615-3p were significantly associated with overall survival in the MCL training set. Their expression was validated in an independent MCL patient set. In comparison with Ki-67, expression of these miRs was more significantly associated with overall survival among patients with MCL. miR-127-3p was combined with Ki-67 to create a new prognostic model for MCL. A similar model was created with miR-615-3p and Mantle Cell Lymphoma International Prognostic Index scores.ConclusionEleven miRs are differentially expressed between aggressive and indolent NHL. Two novel miRs were associated with overall survival in MCL and were combined with clinical prognostic models to generate novel prognostic data for patients with MCL. (C) 2013 by American Society of Clinical Oncology

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O presente trabalho surge em função de buscar um melhor entendimento sobre o papel da torcida, diante dos estados emocionais dos atletas, em especial da ansiedade e da agressividade. Baseado em vasta revisão de literatura, que apresenta as diversas concepções conceituais aqui estudado (adolescência, agressão, ansiedade e torcida) e seus desdobramentos, o estudo assume a vertente da pesquisa qualitativa, optando pela pesquisa participante, como estratégia de verificação. Assim, interessou-se em estudar os aspectos relativos à ação da torcida e sua interferência no comportamento agressivo e ansioso do jogador jovem, que participa de uma modalidade federada, afim de verificar se o aumento da ansiedade e da agressividade, no momento esportivo, reflete o aumento de pressão que se exerce exteriormente. Considerou-se torcida aquele público presente, que assiste aos confrontos esportivos, nas figuras de pais, fãs, familiares e crônica esportiva e o público ausente, como os pais e a imprensa, que ficam no aguardo do resultado, em seus ambientes próprios. Esta pesquisa, exploratória, analisou o contexto esportivo competitivo de atletas das modalidades de basquetebol, futebol de salão, voleibol, handebol, atletismo e natação, observando, entrevistando e coletando falas e expressões que pudessem, após rigorosa categorização, oferecer subsídios para um replanejamento na conduta esportiva de adolescentes. Constatou a grande influência do público, em especial a dos pais, com muito determinismo, seguido do profissional da área esportiva, conforme indicam outros estudos. Explicita a questão da causa efeito no que diz respeito a ansiedade e agressão, oferecendo propostas para trabalhos que possibilitem outra abordagem ou favoreçam outras interferências por parte do público presente.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Abstract Background Lipoprotein-associated phospholipase A2 activity (Lp-PLA2) is a good marker of cardiovascular risk in adults. It is strongly associated with stroke and many others cardiovascular events. Despite this, the impact of obesity on this enzyme activity and its relation to biomarkers of cardiovascular disease in adolescents is not very well investigated. The purpose of this article is to evaluate the influence of obesity and cardiometabolic markers on Lp-PLA2 activity in adolescents. Results This cross-sectional study included 242 adolescents (10–19 years) of both gender. These subjects were classified in Healthy Weight (n = 77), Overweight (n = 82) and Obese (n = 83) groups. Lipid profile, glucose, insulin, HDL size, LDL(−) and anti-LDL(−) antibodies were analyzed. The Lp-PLA2 activity was determined by a colorimetric commercial kit. Body mass index (BMI), waist circumference and body composition were monitored. Food intake was evaluated using three 24-hour diet recalls. The Lp-PLA2 activity changed in function to high BMI, waist circumference and fat mass percentage. It was also positively associated with HOMA-IR, glucose, insulin and almost all variables of lipid profile. Furthermore, it was negatively related to Apo AI (β = −0.137; P = 0.038) and strongly positively associated with Apo B (β = 0.293; P < 0.001) and with Apo B/Apo AI ratio (β = 0.343; P < 0.001). The better predictor model for enzyme activity, on multivariate analysis, included Apo B/Apo AI (β = 0.327; P < 0.001), HDL size (β = −0.326; P < 0.001), WC (β = 0.171; P = 0.006) and glucose (β = 0.119; P = 0.038). Logistic regression analysis demonstrated that changes in Apo B/Apo AI ratio were associated with a 73.5 times higher risk to elevated Lp-PLA2 activity. Conclusions Lp-PLA2 changes in function of obesity, and that it shows important associations with markers of cardiovascular risk, in particular with waist circumference, glucose, HDL size and Apo B/Apo AI ratio. These results suggest that Lp-PLA2 activity can be a cardiovascular biomarker in adolescence.

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In the first chapter, we consider the joint estimation of objective and risk-neutral parameters for SV option pricing models. We propose a strategy which exploits the information contained in large heterogeneous panels of options, and we apply it to S&P 500 index and index call options data. Our approach breaks the stochastic singularity between contemporaneous option prices by assuming that every observation is affected by measurement error. We evaluate the likelihood function by using a MC-IS strategy combined with a Particle Filter algorithm. The second chapter examines the impact of different categories of traders on market transactions. We estimate a model which takes into account traders’ identities at the transaction level, and we find that the stock prices follow the direction of institutional trading. These results are carried out with data from an anonymous market. To explain our estimates, we examine the informativeness of a wide set of market variables and we find that most of them are unambiguously significant to infer the identity of traders. The third chapter investigates the relationship between the categories of market traders and three definitions of financial durations. We consider trade, price and volume durations, and we adopt a Log-ACD model where we include information on traders at the transaction level. As to trade durations, we observe an increase of the trading frequency when informed traders and the liquidity provider intensify their presence in the market. For price and volume durations, we find the same effect to depend on the state of the market activity. The fourth chapter proposes a strategy to express order aggressiveness in quantitative terms. We consider a simultaneous equation model to examine price and volume aggressiveness at Euronext Paris, and we analyse the impact of a wide set of order book variables on the price-quantity decision.

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L’obiettivo del presente progetto di ricerca era determinare se l’utilizzo non clinico del simulatore d’alba (un dispositivo che emette luce in graduale aumento prima del risveglio), basato su specifiche conoscenze cronobiologiche, potesse ridurre alcune delle conseguenze del social jetlag, in studenti di scuola secondaria di secondo grado. A tal fine, sono stati valutati gli effetti del simulatore d’alba su tono dell’umore (valutato soggettivamente tramite la Global and Vigor Affect Scale-GVA), livelli di attivazione (valutati soggettivamente tramite la GVA), qualità/quantità di sonno (valutate oggettivamente e soggettivamente tramite attigrafia e Mini Sleep Questionnaire-MSQ), architettura del sonno (valutata oggettivamente tramite Zeo®) ed efficienza dei tre network attentivi (alerting, orienting ed executive), valutata oggettivamente tramite l’Attention Network Test (ANT). In totale, hanno preso parte alla ricerca 56 adolescenti (24 femmine e 32 maschi), frequentanti due istituti di scuola secondaria di secondo grado nella città di Cesena, la cui età media era di 17.68 anni (range d’età 15-20 anni). Ad ogni studente è stata richiesta una partecipazione di 5 settimane consecutive ed il disegno di ricerca prevedeva 3 condizioni sperimentali: baseline, simulatore d’alba e controllo. All’MSQ, in seguito all’utilizzo del simulatore d’alba, sono state osservate una minore percezione di sonnolenza diurna, una frequenza inferiore di risvegli notturni ed una riduzione del numero di partecipanti che presentavano una cattiva qualità della veglia. All’ANT, è stato documentato un significativo miglioramento dell’efficienza del network attentivo dell’alerting, successivo all’impiego del simulatore d’alba, dovuto ad una maggiore reattività dei partecipanti in seguito alla comparsa del double cue, che anticipava la presentazione del target (freccia centrale di cui i partecipanti dovevano giudicare la direzione). Tali risultati convergono nell’evidenziare la capacità del simulatore d’alba di esercitare un effetto attivante/stimolante, mostrando dunque come esso possa essere considerato uno strumento potenzialmente utilizzabile quale contromisura al social jetlag in adolescenza.