963 resultados para 13200-046
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A new procedure was developed in this study, based on a system equipped with a cellulose membrane and a tetraethylenepentamine hexaacetate chelator (MD-TEPHA) for in situ characterization of the lability of metal species in aquatic systems. To this end, the DM-TEPHA system was prepared by adding TEPHA chelator to cellulose bags pre-purified with 1.0 mol L-1 of HCl and NaOH solutions. After the MD-TEPHA system was sealed, it was examined in the laboratory to evaluate the influence of complexation time (0-24 h), pH (3.0, 4.0, 5.0, 6.0 and 7.0), metal ions (Cu, Cd, Fe, Mn and Ni) and concentration of organic matter (15, 30 and 60 mg L-1) on the relative lability of metal species by TEPHA chelator. The results showed that Fe and Cu metals were complexed more slowly by TEPHA chelator in the MD-TEPHA system than were Cd, Ni and Mn in all pH used. It was also found that the pH strongly influences the process of metal complexation by the MD-TEPHA system. At all the pH levels, Cd, Mn and Ni showed greater complexation with TEPHA chelator (recovery of about 95-75%) than did Cu and Fe metals. Time also affects the lability of metal species complexed by aquatic humic substances (AHS); while Cd, Ni and Mn showed a faster kinetics, reaching equilibrium after about 100 min, and Cu and Fe approached equilibrium after 400 min. Increasing the AHS concentration decreases the lability of metal species by shifting the equilibrium to AHS-metal complexes. Our results indicate that the system under study offers an interesting alternative that can be applied to in situ experiments for differentiation of labile and inert metal species in aquatic systems. (c) 2006 Elsevier B.V. All rights reserved.
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Since Demirjian's system of estimating dental maturity was first described, many researchers from different countries have tested its accuracy among diverse populations. Some of these studies have pointed out a need to determine population-specific standards. In Brazil, the Northeast region is the one that most suffers the negative impact of exodus, specially related to the increase of abandoned children in the cities. The aim of this study was to test the accuracy of Demirjian's system for assessing the dental maturity of northeastern Brazilian children, so as to present a scale for maturity score conversion into dental age developed specifically for this population. This could be used for forensic, anthropological and legal matters, and also as a model for other countries attempting to formulate their own conversion scales. Panoramic radiographs of 1,491 children (821 females and 670 males), aged 7 to 13 years, from Ceará state, northeast Brazil, were assessed by a single observer to determine dental age (DA) according to Demirjian's system. The mean percentage of intra-observer agreement was 86.6%, with a mean Cohen's Kappa coefficient of 0.67 (substantial agreement). The DA was compared by paired t-test to subjects' chronological age (CA). The differences between CA and DA in all age groups were statistically significant (p<0.0001), demonstrating a great advancement in DA among Brazilians. Scatter plots were drawn for both genders, and the data were fitted to a growth curve, y = 100/ (1 + e-a(x b)). Graphs corresponding to the 50th percentile curves were produced. A table with new values for the conversion of maturity score into dental age for northeastern Brazilian children is presented. The great advancement in DA, as obtained by Demirjian's system in this population, justified the determination of specific scores for dental maturity assessment
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Efeitos da deficiência de vitamina A na função pulmonar de crianças após infecção respiratória viral
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Twenty-one lambs averaging 21 kg of live weight fed isoproteic diets based on Rhodes grass hay, ground corn and one of the following protein sources cottonseed meal, urea or sugar cane yeast was used to evaluate the total protein and energy digestibilities and the N balance. The protein digestibilities were 63.4; 68.8 and 62.2% and the energy digestibilities were 58.8; 63.7 and 63.3% for diets with cottonseed meal, urea, and sugarcane yeast, respectively. The daily crude protein intake were 76.2: 72.7 and 69.7 g/day and of gross energy 231.9; 237.6 and 232.1 cal/kg(0.75)/day, for diets with cottonseed meal, urea, and sugarcane yeast, respectively. The results of nitrogen balance and absorbed nitrogen did not show effects of the nitrogen sources being obtained 0.046; 0.112 and -0.081 g/kg(0.75)/day and 7.73; 7.99 and 6.94 g/day for diets with cottonseed meal, urea. and sugarcane yeast, respectively. The utilization of cottonseed meal decreased the energy digestibility in relation to diets with urea or sugarcane yeast, but the nitrogen balance did not show substantial effect of the nitrogen sources.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Studies show the great influence of free radicals and other oxidants as responsible for aging and degenerative diseases. On the other hand, the natural phenolic compounds has shown great as antioxidants to inhibit lipid peroxidation and lipoxygenase in vitro. Among these, is highlighted trans-resveratrol ( 3,5,4 `- trihydroxystilbene ) phenolic compound , characterized as a polyphenol stilbene class. The vegetables popularly known as "Azedinha" (Rumex Acetosa) has trans-resveratrol in its composition and from this, the present work aimed to study on the supercritical extraction and conventional extraction (Soxhlet and sequential) in roots of Rumex Acetosa, evaluating the efficiency of extractive processes, antioxidant activity, total phenolic content and quantification of trans-resveratrol contained in the extracts. Extractions using supercritical CO2 as solvent, addition of co-solvent (ethanol) and were conducted by the dynamic method in a fixed bed extractor. The trial met a 23 factorial design with three replications at the central point, with the variable reply process yield and concentration of trans-resveratrol and pressure as independent variables, temperature and concentration of co-solvent (% v/v). Yields ( mass of dry extract / mass of raw material used ) obtained from the supercritical extraction ranged from 0,8 to 7,63 % , and the best result was obtained at 250 bar and 90 °C using the co-solvent 15% ethanol (% v/v). The value was calculated for YCER a flow rate of 1,0 ± 0,17 g/min resulting in 0,0469 CO2 ( g solute / g solvent ). The results of the mass yield varied between conventional extractions 0,78 % ( hexane) and 9,97 % (ethanol). The statistical model generated from the data of the concentration of trans-resveratrol performed as meaningful and predictive for a 95% confidence. GC analysis on HPLC (High Performance Liquid Chromatography), transresveratrol was quantified in all extracts and concentration values ranged between 0,0033 and 0,42 ( mg / g extract) for supercritical extracts and between 0,449 and 17,046 (mg / g extract) to conventional extractions and therefore, the Soxhlet extraction with ethanol for more selective trans-resveratrol than the supercritical fluid. Evaluation of antioxidant (radical method to sequester 2,2- diphenyl-1- picryl - hydrazyl - DPPH) the supercritical extracts resulted in EC50 values (concentration effective to neutralize 50% of free radicals) of between 7,89 and 18,43 mg/mL , while resulting in a Soxhlet extraction with EC50 values in the range of 6,05 and 7,39 mg/mL. As for quantification of the phenolic compounds (Method Spectrophotometer Folin-Ciocalteau) the supercritical extracts resulted in values between 85,3 and 194,79 mg GAE / g extract, whereas values derived from the Soxhlet extract resulted in values between 178,5 and 237,8 mg GAE / g extract. The high antioxidant activity can not be attributed solely to the presence of phenolic compounds, but the presence of other antioxidants in the existing Rumex acetosa
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Steam explosion process is employed for the successful extraction of cellulose nanofibrils from pineapple leaf fibres for the first time. Steam coupled acid treatment on the pineapple leaf fibres is found to be effective in the depolymerization and defibrillation of the fibre to produce nanofibrils of these fibres. The chemical constituents of the different stages of pineapple fibres undergoing treatment were analyzed according to the ASTM standards. The crystallinity of the fibres is examined from the XRD analysis. Characterization of the fibres by SEM. AFM and TEM supports the evidence for the successful isolation of nanofibrils from pineapple leaf. The developed nanocellulose promises to be a very versatile material having the wide range of biomedical applications and biotechnological applications, such as tissue engineering, drug delivery, wound dressings and medical implants. (C) 2010 Elsevier Ltd. All rights reserved.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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OBJETIVO: Analisar o efeito de 12 semanas de intervenção envolvendo prática de atividade física, orientações alimentar e psicológica sobre fatores de risco para o desenvolvimento da síndrome metabólica em crianças e adolescentes obesos. MÉTODOS: Estudo longitudinal com 23 crianças e adolescentes obesos, com idade entre seis e 16 anos (12,0±3,2 anos). Foram mensurados: gordura corporal total e de tronco, glicemia, colesterol total e triglicérides, pressão arterial sistólica e diastólica. Os jovens foram submetidos a três sessões semanais de 60 minutos de exercício físico (atividades esportivas recreativas, ginástica, circuitos e caminhadas), durante 12 semanas. O teste do qui-quadrado foi usado para comparar dados categóricos daqueles que apresentaram valores acima das recomendações para cada fator de risco. O teste t para dados pareados foi aplicado para comparar os dois momentos do estudo. RESULTADOS: em indivíduos com alterações metabólicas no início do estudo, observou-se, após a intervenção, a diminuição de 11,6% na glicemia (105 para 93mg/dL; p=0,046) e de 24,9% no triglicérides (217 para 163mg/dL; p=0,013); porém, não houve diferenças na pressão arterial e no colesterol total. CONCLUSÕES: O programa de exercício físico aplicado nas crianças e adolescentes foi eficiente para melhorar os valores de glicemia e triglicérides.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Objective: To compare the effects of the treadmill training with partial body-weight support (TPBWS) and Proprioceptive Neuromuscular Facilitation (PNF) method on gait of subjects with chronic stroke. Design: Quasi-experimental study. Setting: Laboratorial research. Participants: Twenty-three subjects (13 men and 10 women), with a mean age of 56,7 ± 8,0 years and a mean time since the onset of the stroke of 27,7 ± 20,3 months, and able to walk with personal assistance or assistive devices. Interventions: Two experimental groups underwent gait training based on PNF method (PNF group, n=11) or using the TPBWS - Gait Trainer System 2, Biodex, USA (TPBWS group, n=12), for three weekly sessions, during four weeks. Measures: Evaluation of motor function - using the Stroke Rehabilitation Assessment of Movement (STREAM) and the motor subscale of the Functional Independence Measure (motor FIM) -, and kinematic gait analyze with the Qualisys System (Qualisys Medical AB, Gothenburg, Sweden) were carried out before and after the interventions. Results: Increases in the STREAM scores (F=49.189, P<0.001) and in motor FIM scores (F=7.093, P=0.016), as well as improvement in symmetry ratio (F=7.729, P=0.012) were observed for both groups. Speed, stride length and double-support time showed no change after training. Differences between groups were observed only for the maximum ankle dorsiflexion over the swing phase (F=6.046, P=0.024), which showed an increase for the PNF group. Other angular parameters remain unchanged. Conclusion: Improvement in motor function and in gait symmetry was observed for both groups, suggesting similarity of interventions. The cost-effectiveness of each treatment should be considered for your choice
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Introduction: The frailty in the elderly is the result of a complex interplay between many social and clinical factors involved in its genesis. Although there is an understanding of its association with increased risk of adverse clinical outcomes, still it is unclear whether this syndrome can be aggravated due to lack of social support. So, the objective of this study was to analyze the association between social support and frailty syndrome in elderly community residents. Materials and methods: Observational analytical cross-sectional study, with a sample of 300 elderly living in the city of Natal-RN. Were collected informations about socialdemographic, economics and physical health data. The Social support was assessed by the status of cohabitation; marital status; contact frequency and diversity rate; received and given attendance frequency rate; and Map Minimum Relations of the Elderly. The frailty was assessed using the following criteria: unintentional weight loss, weakness, low physical activity, exhaustion and Slowness. To observe any possible associations, we performed the Pearson chi-square test, the Student t test and multivariate analysis using binary logistic regression, adopting a significance level of 5%. Results: It was observed that there were no associations of frailty with the social support variables, except for housekeeping mode (p = 0.046) of the MMRI. For the sociodemographic, economic, physical health and social support data, only age (p <0.001), sedentary lifestyle (p = 0.002) and poor perceived health (p = 0.001) were the ones that remained in the logistic regression model, with strong association for the presence of frailty. Conclusion: Among the variables related to social support, only to help with housekeeping was significantly associated with frailty. However, more studies need to be developed to characterize the social vulnerability, as well as health services need to recognize the importance of social support as an integral part of care for the elderly