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91.
Silvana da Silva Valter Carlos Alberto Rodrigues Costa Liliane Cristina Battirola Marcelo Alexandre de Farias Fernando Galembeck Maria do Carmo Gonçalves 《Journal of Polymer Research》2017,24(2):22
The aim of this work was to investigate the polymorphic transformation morphology of isotactic poly(1-butene) (iPB-1) in blends with poly (propylene-co-1-butene-co-ethylene) (terPP). The blends were prepared by solution casting followed by compression-molding and were examined immediately after preparation as well as after aging for over 30 days. Morphological changes were firstly observed by polarized optical microscopy, which showed that the terPP promotes the reduction of the spherulite mean size during the crystallization of iPB-1 from the melt. Digital pulsed force microscopy provided data about the terPP interspersion between the interfibrilar and spherulitic regions of the iPB-1 crystals, causing iPB-1 spherulite deformation. However, a better distribution of the amorphous component on the iPB-1 crystals was observed after phase II to I transition, favored by the rearrangement of iPB-1 lamellae and lamellar stacks during phase transition. 相似文献
92.
Angélica?Ochoa-AvilésEmail author Roosmarijn?Verstraeten Lieven?Huybregts Susana?Andrade John?Van Camp Silvana?Donoso Patricia?Liliana?Ramírez Carl?Lachat Lea?Maes Patrick?Kolsteren 《Nutrition journal》2017,16(1):79
Background
In Ecuador, adolescents’ food intake does not comply with guidelines for a healthy diet. Together with abdominal obesity adolescent’s inadequate diets are risk factors for non-communicable diseases. We report the effectiveness of a school-based intervention on the dietary intake and waist circumference among Ecuadorian adolescents.Methods
A pair-matched cluster randomized controlled trial including 1430 adolescents (12–14 years old) was conducted. The program aimed at improving the nutritional value of dietary intake, physical activity (primary outcomes), body mass index, waist circumference and blood pressure (secondary outcomes). This paper reports: (i) the effect on fruit and vegetable intake, added sugar intake, unhealthy snacking (consumption of unhealthy food items that are not in line with the dietary guidelines eaten during snack time; i.e. table sugar, sweets, salty snacks, fast food, soft drinks and packaged food), breakfast intake and waist circumference; and, (ii) dose and reach of the intervention. Dietary outcomes were estimated by means of two 24-h recall at baseline, after the first 17-months (stage one) and after the last 11-months (stage two) of implementation. Dose and reach were evaluated using field notes and attendance forms. Educational toolkits and healthy eating workshops with parents and food kiosks staff in the schools were implemented in two different stages. The overall effect was assessed using linear mixed models and regression spline mixed effect models were applied to evaluate the effect after each stage.Results
Data from 1046 adolescents in 20 schools were analyzed. Participants from the intervention group consumed lower quantities of unhealthy snacks (?23.32 g; 95% CI: ?45.25,-1.37) and less added sugar (?5.66 g; 95% CI: ?9.63,-1.65) at the end of the trial. Daily fruit and vegetable intake decreased in both the intervention and control groups compared to baseline, albeit this decrease was 23.88 g (95% CI: 7.36, 40.40) lower in the intervention group. Waist circumference (?0.84 cm; 95% CI: ?1.68, 0.28) was lower in the intervention group at the end of the program; the effect was mainly observed at stage one. Dose and reach were also higher at stage one.Conclusions
The trial had positive effects on risk factors for non-communicable diseases, i.e. decreased consumption of unhealthy snacks. The program strategies must be implemented at the national level through collaboration between the academia and policy makers to assure impact at larger scale.Trial registration
ClinicalTrial.gov-NCT01004367.93.
Montanaro MA Rimoldi OJ Igal RA Montenegro S Tarrés MC Martínez SM Brenner RR 《Lipids》2003,38(8):827-832
Both diabetes mellitus type 1 and diabetes mellitus type 2 are widespread diseases that alter carbohydrate and lipid metabolism.
e Stilmann-Salgado (eSS) rats are experimental animals that spontaneously evolve to a state similar to that of young people
affected by non-insulin-dependent diabetes mellitus (NIDDM; type 2). Using 6-mon-old eSS rats that, according to the literature
[Martinez, S.M., Tarrés, M.C., Montenegro, S, Milo, R., Picena, J.C., Figueroa, N., and Rabasa, S.R. (1988) Spontaneous Diabetes
in eSS Rats, Acta Diabetol. Lat. 25, 303–313], had already developed insulin resistance, we investigated the changes evoked on Δ9, Δ6, and Δ5 liver desaturases.
The abundance of mRNA and enzymatic activities were measured, as well as the FA composition of liver microsomal lipids. Compared
to control rats, the mRNA content and activity of SCD-1 (stearoyl CoA-desaturase, isoform of the Δ9 desaturase) were significantly
higher, urase, isoform of the Δ9 desaturase) were significantly higher, whereas the mRNA and activities of Δ6 and Δ5 desaturases
were not significantly modified. Correspondingly, the proportion of 18∶1n−9 and the ratios of 18∶1n−9/18∶0 and 16∶1/16∶0 in
lipids were significantly increased, whereas the proportion of 20∶4n−6 was unaltered. These effects were found while glycemia
was constant or increased. The results are completely opposite those described in insulin-dependent diabetes mellitus (type
1), in which a depression of all the desaturases is found. They suggest that in eSS rats, the activities of the desaturases
were not modified by an insulin-resistance effect. Moreover, we suggest that the enhancement of SCD-1 activity might be considered
as another typical sign of the NIDDM syndrome, because it has also been found in other animal models of NIDDM, for example,
the ones evoked by the sucrose-rich diet and in the Zucker rat. 相似文献
94.
Stefano Montanelli Devis Bianchini Carola Aiello Roberto Baldoni Cristiana Bolchini Silvia Bonomi Silvana Castano Tiziana Catarci Valeria De Antonellis Alfio Ferrara Michele Melchiori Elisa Quintarelli Monica Scannapieco Fabio A. Schreiber Letizia Tanca 《Journal of Intelligent Information Systems》2011,36(2):167-195
In this paper, we present Esteem (Emergent Semantics and cooperaTion in multi-knowledgE EnvironMents), a community-based P2P platform for supporting semantic collaboration among a set of independent peers, without prior reciprocal knowledge and no predefined relationships. Goal of Esteem is to go beyond the existing state-of-the-art solutions for P2P knowledge sharing and to provide an integrated platform for both data and service discovery. A distinguishing feature of Esteem is the use of semantic communities to explicitly give shape to the collective knowledge and expertise of peer groups with similar interests. Key techniques of Esteem will be presented in the paper and concern: shuffling-based communication, ontology and service matchmaking, context management, and quality-aware data integration. An application example of data and service discovery in the health-care domain will be presented, by also discussing results of system and user evaluation. 相似文献
95.
Silvana Fiorito Marc Monthioux Pasquale Pierimarchi Enrico D’Emilia Antonella Lisi Robert Almairac Annalucia Serafino 《Carbon》2009,47(12):2789-817
Carbon multi-walled nanotubes (MWCNTs) may have several dangerous effects on different cell systems, but the mechanisms responsible for their cytotoxicity are not well known yet. At present, very little is known about the electrical interactions between nanomaterials and cells. We aimed to verify whether MWCNT electrical properties could affect the so called “charge-sensitive” cell parameters, interacting with cellular electrical activity. Human macrophages were challenged with two fully characterised MWCNT samples, one tested as-prepared (MWCNT), the other one purified (by annealing at 2400 °C) and better electro-conductive (a-MWCNT). Our findings show that a-MWCNTs are less cytotoxic but possess a higher inflammatory potential, as compared to MWCNTs. Moreover, only annealed and better conductive MWCNTs affect significantly the mitochondrial membrane polarity, the intracellular pH and the reorganisation of cytoskeleton actin filaments, cell functions strictly dependent on electro-chemical mechanisms. Based on our results, there is evidence for electro-chemical interactions taking place between cell membranes and electro-conductive MWCNTs. Such a specific behaviour could have wide-range applications in the biomedical field, not only concerning those cellular systems (neuronal and bone cells) sensitive to electrical stimuli, but also other cell systems. 相似文献
96.
Giuseppe Calcagno Antonino Staiano Giuliana Fortunato Vincenzo Brescia-Morra Rosario Liguori Silvana Capone Alessandro Filla Lucia Sacchetti 《Information Sciences》2010,180(21):4153-185
Multiple sclerosis is an idiopathic inflammatory disease characterized by multiple focal lesions in the white matter of the central nervous system. Multiple sclerosis patients are usually treated with interferon-β, but disease activity decrease in only 30-40% of patients. In the attempt to differentiate between responders and non-responders, we screened the main genes involved in the interferon signaling pathway for 38 single nucleotide polymorphisms (SNPs) in a multiple sclerosis Caucasian population from South Italy. We then analyzed the data using a multilayer perceptron neural network-based approach, in which we evaluated the global weight of a set of SNPs localized in different genes and their association with response to interferon therapy through a feature selection procedure (a combination of automatic relevance determination and backward elimination). The neural approach appears to be a useful tool in identifying gene polymorphisms involved in the response of patients to interferon therapy: 2 out of 5 genes were identified as containing 4 out of 38 significant single nucleotide polymorphisms, with a global accuracy of 70% in predicting responder and non-responder patients. 相似文献
97.
Determination of inorganic trace elements in edible marine fish from Rio de Janeiro State, Brazil 总被引:2,自引:0,他引:2
Renata J. Medeiros Lisia Maria G. dos SantosAline S. Freire Ricardo E. SantelliAna Maria C.B. Braga Thomas M. Krauss Silvana do C. Jacob 《Food Control》2012,23(2):535-541
Fish and seafood may represent risk for human health since they can accumulate contaminants from aquatic environment and magnify them up the food chain. The purpose of this study was to analyze and evaluate the levels of aluminum, zinc, iron, manganese, cobalt, copper, arsenics, selenium, cadmium, barium, lead and bismuth in 11 fish species (Salmo salar, Sardinella brasiliensis, Pomatomus saltatrix, Micropogonias furnieri, Cynoscion leiarchus, Caranx crysos, Priacanthus arenatus, Mugil cephalus, Genypterus brasiliensis, Lopholatilus villarii and Pseudopercis numida) captured at Rio de Janeiro State Coast, Brazil. Concentration ranges (mg kg−1 of wet weight) of the selected elements were compared with those reported in other studies. In some cases, comparison of certain elements in the same fish species was difficult due to the lack of data. Aluminum concentration was significantly high in all samples and only M. cephalus, C. leiarchus e C. crysos presented arsenic concentrations below 1 mg kg−1, limit recommended by Brazilian legislation. 相似文献
98.
Rossella Di Monaco Silvana Cavella Paolo Masi Agostino Sevi Mariangela Caroprese Alessandra Marzano Amalia Conte & Matteo Alessandro Del Nobile 《International Journal of Food Science & Technology》2009,44(8):1634-1641
In order to reduce waste of marine resources, valorise fishing discards and move towards fish consumption, a new ready-to-cook seafood product was developed. In particular, a chemical investigation on chub mackerel and hake was conducted to the aim of mixing the two fish species to produce nutritionally balanced fish burgers. In addition, to evaluate consumer opinion about these new fresh products and best acceptability of different proportions of mackerel and hake, focus group interviews and consumer test were also performed. The results of the chemical analyses achieved on both selected fish species gave rise to minimally processed fish products with a high amount of chub mackerel, therefore providing the desired nutritional properties and low level of hake in order to obtain firmer and wetter burgers. By means of focus group interviews, the novelty and high level of convenience of the developed fresh commodity was highlighted. Consumer test declared that the most successful sample was that with 70% chub mackerel and 30% hake. 相似文献
99.
Silvana T Silveira Manuela K Jaeger Adriano Brandelli 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(3):361-366
BACKGROUND: Keratinases are important enzymes for biotechnological processes involving keratin hydrolysis. In this work substrate specificity and kinetic properties of a keratinase from Chryseobaterium sp. were investigated. RESULTS: The optimal conditions for activity of purified keratinase with respect to pH, temperature and sodium chloride concentration were established using factorial design and surface response techniques. The optimum conditions for keratinase activity were pH from 7.4 to 9.2, temperature from 35 °C to 50 °C and NaCl concentration from 50 to 340 mmol L?1, having azocasein as substrate. Subsequently, the kinetic parameters for this substrate were determined to be Km = 0.75 mg mL?1 and Vmax = 59.5 U min?1. The Ki value for 1,10‐phenanthroline was estimated at 0.78 mmol L?1. The enzyme specificity was evaluated over different synthetic and insoluble substrates. The protease exhibited specificity with selectivity for hydrophobic and positively charged residues. In relation to the insoluble substrates, the enzyme hydrolyzed preferably chicken nails. CONCLUSIONS: This enzyme effectively hydrolyzes insoluble keratin substrates. The knowledge of keratinase properties is an essential step in the development of biotechnological processes involving keratin hydrolysis. Copyright © 2008 Society of Chemical Industry 相似文献
100.
Jucélia Pizzetti Benincá Ana Beatriz Montanher Silvana Maria Zucolotto Eloir Paulo Schenkel Tania Silvia Fröde 《Food chemistry》2007,104(3):1097-1105
The aim of this study was to investigate the anti-inflammatory effect of the aqueous extract of Passiflora edulis forma flavicarpa Degenerer leaves in the air pouch inflammation model induced by carrageenan, histamine or substance P, in mice. An aqueous extract was prepared by infusion and lyophilized. Part of the extract was fractionated with n-butanol, resulting in the butanolic and aqueous residual fractions. The anti-inflammatory activities of the lyophilized extract and these two derived fractions were evaluated. In the inflammation induced by carrageenan, aqueous extract (100 mg/kg, i.p.), butanolic fraction (50 mg/kg, i.p.), aqueous residual fraction (100 mg/kg, i.p.) and dexamethasone (0.5 mg/kg, i.p.) inhibited the leukocyte, neutrophil, myeloperoxidase, nitric oxide, and interleukin-1 beta (IL-1β) levels (p < 0.05). The aqueous extract and butanolic and aqueous residual fractions, but not dexamethasone, decreased macrophage inflammatory protein-2 (MIP-2) levels (p < 0.05). Only dexamethasone inhibited mononuclear cells (p < 0.01). In the inflammation induced by histamine, the aqueous extract, butanolic and aqueous residual fractions, and dexamethasone inhibited total and differential leukocytes (p < 0.01). In the inflammation induced by substance P, the aqueous extract, butanolic and aqueous residual fractions, and dexamethasone also inhibited total leukocytes and mononuclears (p < 0.01). Neutrophils were only inhibited by aqueous extract, butanolic fraction, and dexamethasone (p < 0.05). In conclusion, the active principle(s) present in the P. edulis aqueous extract and its two fractions showed pronounced anti-inflammatory properties, inhibiting cell migration, proinflammatory cytokines, enzymes and mediators. 相似文献