884 resultados para Baeza
Resumo:
The night-time tropospheric chemistry of two stress-induced volatile organic compounds (VOCs), (Z)-pent-2-en-1-ol and pent-1-en-3-ol, has been studied at room temperature. Rate coefficients for reactions of the nitrate radical (NO3) with these pentenols were measured using the discharge-flow technique. Because of the relatively low volatility of these compounds, we employed off-axis continuous-wave cavity-enhanced absorption spectroscopy for detection of NO3 in order to be able to work in pseudo first-order conditions with the pentenols in large excess over NO3. The rate coefficients were determined to be (1.53 +/- 0.23) x 10(-13) and (1.39 +/- 0.19) x 10(-14) cm(3) molecule(-1) s(-1) for reactions of NO3 with (Z)-pent-2-en-1-ol and pent-1-en-3-ol. An attempt to study the kinetics of these reactions with a relative-rate technique, using N2O5 as source of NO3 resulted in significantly higher apparent rate coefficients. Performing relative-rate experiments in known excesses of NO2 allowed us to determine the rate coefficients for the N2O5 reactions to be (5.0 +/- 2.8) x 10(-19) cm(3) molecule(-1) s(-1) for (Z)-pent-2-en-1-ol, and (9.1 +/- 5.8) x 10(-19) cm(3) molecule(-1) s(-1) for pent-1-en-3-ol. We show that these relatively slow reactions can indeed interfere with rate determinations in conventional relative-rate experiments.
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Increasing evidence suggests that obesity is a chronic inflammatory disease, in which adipose tissue is involved in a network of endocrine signals to modulate energy homeostasis. These oxidative-inflammatory pathways, which are associated with cardiovascular complications, are also observed during the aging process. In this study, we investigated the interaction between aging and the development of obesity in a hyperphagic rat model. Metabolic profiles of the liver, white adipose tissue (WAT) and heart from young and adult Zucker lean (fa/+) and obese (fa/fa) rats were characterized using a (1)H NMR-based metabonomics approach. We observed premature metabolic modifications in all studied organs in obese animals, some of which were comparable to those observed in adult lean animals. In the cardiac tissue, young obese rats displayed lower lactate and scyllo-inositol levels associated with higher creatine, choline and phosphocholine levels, indicating an early modulation of energy and membrane metabolism. An early alteration of the hepatic methylation and transsulfuration pathways in both groups of obese rats indicated that these pathways were affected before diabetic onset. These findings therefore support the hypothesis that obesity parallels some metabolic perturbations observed in the aging process and provides new insights into the metabolic modifications occurring in pre-diabetic state.
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Eating attitudes are defined as beliefs, thoughts, feelings, behaviors and relationship with food They could influence people`s food choices and their health status Objective This study aimed to adapt from Portuguese to English the Disordered Eating Attitude Scale (DEAS) and evaluate its validity and reliability. The original scale in Portuguese was translated and adapted into English and was applied to female university students of University of Minnesota USA (n = 224). Internal consistency was determined (Cronbach`s Alpha). Convergent validity was assessed by correlations between Eating Attitude Test-26 (EAT-26) and Restrain Scale (RS). Reliability was evaluated applying twice the scale to a sub-sample (n = 30). The scale was back translated into Portuguese and compared with the original version and discrepancies were not found. The internal consistency was .76 The DEAS total score was significantly associated with EAT-26 (r = 0.65) and RS (r = 0 69) scores The correlation between test-retest was r = 09 The English version of DEAS showed appropriate internal consistency, convergent validity and test-retest reliability and will be useful to assess eating attitudes in different population groups in English spoken countries. (C) 2010 Elsevier Ltd. All rights reserved
Resumo:
The aim of this study was to develop and validate the Disordered Eating Attitude Scale to measure disordered eating attitudes, defined as abnormal beliefs, thoughts, feelings, behaviors, and relationship regarding food. Exploratory factor analysis was performed and internal consistency assessed in a sample of female university students (N=196). Convergent validity was acceptable based on statistically significant correlations with the Eating Attitude Test-26 and Restraint Scale. Known-groups validity was determined by comparing the student sample`s mean scores against scores of an eating disorder group (N=51). The Disordered Eating Attitude Scale comprises 25 questions and five subscales explaining 54.3% of total variance. The total scores differentiated student, bulimia, and anorexia groups. The scale should prove useful for evaluating eating attitudes in various population groups and eating disordered patients.
Resumo:
Eating attitudes are defined as beliefs. thoughts, feelings and behaviors towards food. Bulimia nervosa (BN) is ail eating disorder, in which the eating, attitudes are Seriously disturbed. Studies that evaluated nutritional aspects of BN focus mainly oil food intake, dietary restriction and binge eating. while the follow-up Studies evaluate mainly clinical symptoms. The objective of this study was to evaluate eating attitudes of patients with BN. during and after cognitive-behavioral intervention. Thirty nine (39) BN female patients received cognitive behavioral treatment with a Multidisciplinary team and had eating attitudes assessed by a questionnaire developed for this research. Frequencies of the attitudes assessed were compared at baseline. after 12 weeks and 24 weeks of treatment. After treatment, patients had less distorted beliefs about food, less guilty after eating ""forbidden"" foods and they felt more tranquil while caring outside home. Other negative behaviors, as dietary restriction, the desire of not cat, being angry when feeling hungry and using the food to relive stress. persisted. Eating attitudes of patients with BN are hard to be changed in a short-term. More attention to this disease`s component and new approaches to treatment are needed in order to have a better recovery.
Resumo:
The sexual system of the symbiotic shrimp Thor amboinensis is described, along with observations on sex ratio and host-use pattern of different populations. We used a comprehensive approach to elucidate the previously unknown sexual system of this shrimp. Dissections, scanning electron microscopy, size-frequency distribution analysis, and laboratory observations demonstrated that T amboinensis is a protandric hermaphrodite: shrimp first mature as males and change into females later in life. Thor amboinensis inhabited the large and structurally heterogeneous sea anemone Stichoclactyla helianthus in large groups (up to 11 individuals) more frequently than expected by chance alone. Groups exhibited no particularly complex social structure and showed male-biased sex ratios more frequently than expected by chance alone. The adult sex ratio was male-biased in the four separate populations studied, one of them being thousands of kilometers apart from the others. This study supports predictions central to theories of resource monopolization and sex allocation. Dissections demonstrated that unusually large males were parasitized by an undescribed species of isopod (family Entoniscidae). Infestation rates were similarly low in both sexes (approximate to 11%-12%). The available information suggests that T. amboinensis uses pure search promiscuity as a mating system. This hypothesis needs to be formally tested with mating behavior observations and field measurements on the movement pattern of both sexes of the species. Further detailed studies on the lifestyle and sexual system of all the species within this genus and the development of a molecular phylogeny are necessary to elucidate the evolutionary history of gender expression in the genus Thor.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Trichophyton rubrum é um importante agente causal de dermatomicose. Os métodos de tipagem molecular têm sido recentemente desenvolvidos para responder questões sobre epidemiologia e auxiliar no esclarecimento de recidivas, após o tratamento. As seqüências aleatórias 1- (5'-d[GGTGCGGGAA]-3') e 6- (5'-d[CCCGTCAGCA]-3') foram usadas para tipagem molecular deste fungo por RAPD produzindo variabilidade intraespecífica. Cinco padrões foram observados entre os 10 isolados de T. rubrum, com ambas as seqüências. Foi concluído que a análise por RAPD pode ser utilizada para estudos epidemiológicos.
Resumo:
Trichophyton rubrum is the most common pathogen causing dermatophytosis. Molecular strain-typing methods have recently been developed to tackle epidemiological questions and the problem of relapse following treatment. A total of 67 strains of T rubrum were screened for genetic variation by randomly amplified polymorphic DNA (RAPD) analysis, with two primers, 5'-d[GGTGCGGGAA]-3' and 5'-d[CCCGTCAGCA]-3', as well as by subrepeat element analysis of the nontranscribed spacer of rDNA, using the repetitive subelements TRS-1 and TRS-2. A total of 12 individual patterns were recognized with the first primer and 11 with the second. Phylogenetic analysis of the RAPID products showed a high degree of similarity (> 90 %) among the epidemiologically related clinical isolates, while the other strains possessed 60% similarity. Specific amplification of TRS-1 produced three strain-characteristic banding patterns (PCR types); simple patterns representing one copy of TRS-1 and two copies of TRS-2 accounted for around 85 % of all isolates. It is concluded that molecular analysis has important implications for epidemiological studies, and RAPID analysis is especially suitable for molecular typing in T. rubrum.