81 research outputs found

    Effect of relative humidities on microstructural, barrier and mechanical properties of Yam starch-monoglyceride films

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    The effect of monoglyceride on microstructural, barrier and mechanical properties of casted yam starch films were investigated in different relative humidities (RH) and compared with glycerol-starch films. A single screw extruder was used to produce the starch - monoglyceride complex before film production and this process was effective to inhibit the phase separation in films. The addition of the hydrophobic compound reduced hydrophobicity, transparency and water vapor permeability of films. This later value for starch-glycerol film (1.7 x 10-10 g Pa-1 s-1 m-1) was higher than starch (1.2 x 10-10 g Pa-1 s-1 m-1) and monoglyceride-starch films (1.0 x 10-10 g Pa-1 s-1 m-1). Films containing glycerol had higher relative crystallinity (B and V H) with a slight increase at higher RH values, while for monoglyceride films, the crystallinity was constant. Monoglyceride-starch films presented poor mechanical properties when compared to glycerol- starch ones but they presented a stable behavior under different relative humidities.Estudou-se o efeito da adição de monoglicerídeo nas propriedades microestruturais, mecânicas e de barreira de filmes de amido de inhame, em diferentes umidades relativas (UR), comparando-as com as de filmes de amido- glicerol. Uma extrusora mono-rosca foi usado para produzir o complexo amido-monoglicerídeo, antes de produzir o filme, e o processo foi efetivo para inibir a separação de fases que geralmente ocorre nesse tipo de filmes. A adição de monoglicerídeo, que é um composto hidrofóbico, reduziu a hidrofilicidade, a transparência e a permeabilidade ao vapor de água dos filmes. O valor desta, para os filmes de amido-glicerol (1,7 x 10-10 g Pa-1 s-1 m-1) foi maior que para os de amido (1,2 x 10-10 g Pa-1 s-1 m-1) e para os de amido-monoglicerídeo (1,0 x 10-10 g Pa-1 s-1 m-1). Os filmes com glicerol tiveram maior cristalinidade relativa (B e V H), com um ligeiro aumento em altas UR, enquanto que nos filmes com monoglicerídeo a cristalinidade foi constante. Os filmes de amido-monoglicerídeo apresentaram piores propriedades mecânicas que os filmes de amido-glicerol, mas foram mais estáveis sob diferentes umidades relativas.15051512Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

    Endurance training induces depot-specific changes in IL-10/TNF-α ratio in rat adipose tissue

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    White adipose tissue (WAT) is the source of pro- and anti-inflammatory cytokines and recently, it recognized as an important source of interleukin 10 production (IL-10). Acute physical exercise induce an anti-inflammatory cytokine profile. However, the effect of chronic physical exercise in the production of IL-10 by the WAT has never been examined. IL-10 and TNF-α were assessed in WAT of rats engaged in endurance training. Animals were randomly assigned to either a sedentary control group (S, n=7) or an endurance trained group (T, n=8). Trained rats ran on a treadmill for 5 days/wk for 8 wk at 55-65% of the VO2max. Detection of IL-10 and TNF-α protein (by ELISA) and mRNA expression (by semi-quantitative PCR), as well as the mRNA of PPARγ, and immunocytochemistry to detect mononuclear phagocytes were carried out. A reduction in absolute retroperitoneal adipose tissue (RPAT) weight in T (44%; p\u3c0.01), when compared with S was observed. IL-10 and TNF-α concentration were increased (60% p\u3c0.05; 40%, p\u3c0.05, respectively), in the mesenteric adipose tissue (MEAT) from the trained group, while no change related to training was observed in RPAT. In MEAT, IL-10/TNF-α ratio was increased for T group when compared with S (30%; p\u3c0.05). PPAR-γ mRNA was increased in T (1.1 fold; p\u3c0.01) when compared with S in the same adipose depot. No monocyte infiltration was found. In conclusion, exercise training induced increased IL-10 expression in the mesenteric depot, resulting in a modified IL-10/ TNF-α ratio. We also conclude that WAT presents a depot-specific response to endurance training

    Influence of aerobic physical training in the motochondrial transport of long chain fatty acids in the skeletal muscle: role of the carnitine palmitoil transferase

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    O ácido graxo (AG) é uma importante fonte de energia para o músculo esquelético. Durante o exercício sua mobilização é aumentada para suprir as necessidades da musculatura ativa. Acredita-se que diversos pontos de regulação atuem no controle da oxidação dos AG, sendo o principal a atividade do complexo carnitina palmitoil transferase (CPT), entre os quais três componentes estão envolvidos: a CPT I, a CPT II e carnitina acilcarnitina translocase. A função da CPT I durante o exercício físico é controlar a entrada de AG para o interior da mitocôndria, para posterior oxidação do AG e produção de energia. Em resposta ao treinamento físico há um aumento na atividade e expressão da CPT I no músculo esquelético. Devido sua grande importância no metabolismo de lipídios, os mecanismos que controlam sua atividade e sua expressão gênica são revisados no presente estudo. Reguladores da expressão gênica de proteínas envolvidas no metabolismo de lipídios no músculo esquelético, os receptores ativados por proliferadores de peroxissomas (PPAR) alfa e beta, são discutidos com um enfoque na resposta ao treinamento físico.Fatty acids are an important source of energy for the skeletal muscle. During exercise, their mobilization is increased to supply the muscle energetic needs. Many points of regulation act in the fatty acids metabolism, where the carnitine palmytoiltransferase (CPT) complex is the main control system. Three compounds named CPT I, CPT II and carnitine acyl carnitine translocase (CACT) are components of this system. Its function is to control the influx of fatty acids inside the mitochondria for posterior oxidation and energy production. There is a pronounced increase in both activity and gene expression of CPT I in the skeletal muscle in response to exercise. Due to its importance in lipid metabolism, the controlling mechanisms are reviewed in the present study. The modulation of gene expression by peroxisome proliferator-activated receptors (PPARs) alpha and beta during the physical training is also discussed in this review

    Effect of a gelatin-based edible coating containing cellulose nanocrystals (CNC) on the quality and nutrient retention of fresh strawberries during storage

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    Strawberry is a non-climacteric fruit with a very short postharvest shelf-life. Loss of quality in this fruit is mostly due to its relatively high metabolic activity and sensitivity to fungal decay, meanly grey mold (Botrytis cinerea). In this study, the ability of gelatin coatings containing cellulose nanocrystals (CNC) to extend the shelf-life of strawberry fruit (Fragaria ananassa) over 8 days were studied. The filmogenic solution was obtained by the hydration of 5 g of gelatin (GEL) in 100 mL of distillated water containing different amounts of CNC dispersion (10 mg CNC/g of GEL or 50 mg of CNC/g of GEL) for 1 hour at room temperature. After this period, the solution was heated to 70 ºC and maintained at this temperature for 10 minutes. The plasticizer (glycerol) (10g/100g of the GEL) was then added with constant, gentle stirring in order to avoid forming air bubbles and also to avoid gelatin denaturation until complete homogenization. Strawberries (purchased at the local market) were immersed in the filmogenic solution for 1 minute and after coated were dried at 15 ºC by 24 hours. The strawberries were then kept under refrigeration and characterized in terms of their properties (weight loss, ascorbic acid content, titratable acidity, water content). The results have shown that samples covered with GEL/CNC had a significant improvement in its shelflife. For instance, for the control sample (without coating) the weight loss after 8 days of storage was around 65%, while covered samples loss in the range of 31-36%. Edible coating was also effective in the retention of ascorbic acid (AA) in the strawberries, while control sample presented a fast decay in the AA content, covered samples showed a slow decay in the AA concentration. Moreover, the use of GEL/CNC edible coating had an antimicrobial effect in the fruitsPostprint (published version

    Estudo da miscibilidade de blendas de poli (ácido lático)/ poli (butileno adipato-co-tereftalato) preparadas pelo método de evaporação de solvente

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    A produção de blendas de PLA/ PBAT tem por objetivo superar as desvantagens que cada polímero possui individualmente, como fragilidade, limitações de processabilidade e custo. Neste estudo, investigamos a miscibilidade e as propriedades de filmes biodegradáveis de PLA - Poli (ácido lático), PBAT- Poli (butileno adipato-co-tereftalato) e de suas blendas com proporções de 95/5, 70/30, 30/70 e 5/95 de PLA/PBAT, respectivamente, produzidos pelo método de evaporação de solvente. As blendas produzidas foram caracterizadas pelas técnicas de espectroscopia Raman, calorimetria exploratória diferencial (DSC), termogravimetria (TGA), microscopia eletrônica de varredura (MEV), viscosimetria de soluções diluídas e ensaio mecânico de tração. A análise dos espectros Raman, temperatura de transição vítrea (Tg), e TGA indicaram imiscibilidade dos polímeros em todas as composições estudadas. As análises mecânicas apontaram para diminuição da rigidez das blendas com a adição do PBAT. Os valores dos parâmetros de interação obtido pela análise de viscosimetria de soluções diluídas, sugerem miscibilidade parcial da blenda contendo 5% de PBAT. O estudo da miscibilidade e das propriedades das blendas de PLA/PBAT obtidas por evaporação de solvente possibilitarão a produção de novos materiais por diferentes técnicas visando novas aplicação para este material.Palavras-chave: Poli (ácido lático). Poli (butileno adipato-co-tereftalato). Blendas. Misicibilidade. Viscosidade. Espectroscopia Raman.

    Low and moderate intensity strength exercise affects more beneficially the lipid profile than high intensity strength exercise

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    This study aimed to compare the time-course effects of four different intensities of strength exercise (bench press) bouts on the blood lipid profile. Thirty-five Brazilian Army male soldiers were allocated randomly into five groups based at different percentages of one repetition maximum, in previous test (1-RM): 50%-1RM, 75%-1RM, 90%-1RM, 110%-1RM (this executing only eccentric phase), and control group. The total volume (sets x reps x load) of the exercise was equalized. The lipid profile (Triglycerides, VLDL, HDL-cholesterol, LDL-cholesterol, HDL-c/Total Cholesterol ratio and Total cholesterol) was determined at rest and after 1, 24, 48 and 72 h of the strength exercise. The 75% group demonstrated greater TG and VLDL reduction when compared with the other groups (p\u3c0.05). Additionally, the 110% group presented an increased TG and VLDL concentration when compared with the control, 50% and 75% groups (p\u3c0.05). HDL-c concentration was significantly greater after strength exercise at 50% and 75% when compared with 110% (p\u3c0.05). Accordingly, the 50% and control groups had greater HDL-c concentration than 110% group after 48 h and 72 h (p\u3c0.05). Finally, The 50% group showed lesser LDL-c concentration than 110% group after 24 h (p\u3c0.05). No significant differences were found in Total Cholesterol and HDL-c/Total cholesterol ratio concentration. Results indicate that acute strength exercise changes lipid profile in a specific-intensity manner. Overall, low and moderate exercise intensities appear to promote more benefits on lipid profile than high intensity. Long term studies should confirm these findings

    Biodegradable films with high starch content made by blown extrusion: solubility and effective diffusion coefficients and water vapor permeability

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    O grande volume de plástico descartado atualmente tem causado problemas sanitários e ambientais. Investigações têm sido feitas sobre a produção de filmes plásticos a partir de polímeros de fontes renováveis, como o amido de mandioca, que é abundante e de baixo custo no Brasil. Este trabalho teve como objetivo a caracterização quanto às propriedades de sorção de água de filmes biodegradáveis com alto teor de amido de mandioca termoplástico e poli(butileno adipato co-tereftalato) (PBAT), produzidos por extrusão. Foram determinadas a permeabilidade ao vapor de água dos filmes, isotermas de sorção de água e os coeficientes de solubilidade (ß) e de difusão efetivo (Dw) de água. As propriedades de sorção de água de filmes de blendas de ATp/PBAT com alto teor de amido são afetadas pela umidade relativa do ar e pelo teor de amido dos filmesPostprint (published version

    Efeito da temporada de basquetebol profissional sobre o perfil lipídico

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    The aim of the present study was to verify the effect of the professional basketball season on the lipids profile. Seven professional players (age: 23.6±4.3 years; body mass: 110.2±17.5 kg; height: 195.4±10.3 cm) were evaluated before and after a period ranging 4 moths, during national professional basketball season (2 games per week, 2 to 3 tactical and technical exercise workout, 2 to 3 strength exercise workout, 1 to 2 recuperative workout and 1 day of passive rest, all of then as a median per week). Blood samples and anthropometric measures were taken. The first visit was made before the beginning of the season and the second visit two days (48 hours) after the ending of the last game of the season. The lipids profile (triglyceride, VLDL, LDL-cholesterol, HDL-cholesterol, and total cholesterol) was analyses by commercial kits (Labtest®, Brazil). The comparison between the results (before and after) was carried through by non-parametric Wilcoxon pair test. The level of significance of 5% was used (p < 0.05). After basketball season, a reduction in the LDL-cholesterol plasma concentrations was demonstrated (before: 111.40±9 mg/dL after: 84.60±8.50 mg/dL; p < 0.05), as well as in total cholesterol (before: 171.20±6.44 mg/dL after: 148.20±6.37 mg/dL; p < 0.05). Besides, increase in rate the HDL/total cholesterol was found (before: 0.22±0.03 after: 0.27±0.06; p < 0.05). The results herein found indicate that the basketball season may induce changes in LDL-cholesterol, total cholesterol and in rate the HDL/total cholesterol concentrations, suggesting a modulatory effect on the lipid profile in professional basketball player after 4 moths season.O objetivo do presente estudo foi verificar o efeito da temporada de basquetebol profissional sobre o perfil lipídico. Sete jogadores profissionais (idade: 23,6±4,3 anos; massa corporal: 110,2±17,5 kg; estatura: 195,4±10,3 cm) foram avaliados antes e após um período de 4 meses, relativos a uma temporada nacional de basquetebol profissional (2 partidas por semana, 2 a 3 sessões de treinos técnicos e tático, 2 a 3 sessões de treino de musculação, 1 a 2 sessões de treino regenerativo e 1 dia de descanso passivo, sendo todos a média por semana) . Os jogadores foram submetidos a analise antropométrica e coleta sangüínea. A primeira visita foi feita antes do início da temporada e a segunda visita dois dias (48 horas) após o término da última partida da temporada. Foram realizadas análises do perfil lipídico (triacilglicerol, VLDL, LDL-colesterol, HDL-colesterol, e colesterol total) por kits comerciais (Labtest®, Brasil). A comparação entre os resultados foi realizada pareadamente (antes e depois o início da temporada) por teste não paramétrico de Wilcoxon. Utilizou-se o nível de significância de 5% (p < 0,05). Após a temporada, foi demonstrada diminuição nas concentrações da LDL-colesterol (pré: 111,40±9 mg/dL vs pós: 84,60±8,50 mg/dL; p < 0,05), bem como do colesterol total (pré: 171,20±6,44 mg/dL vs pós: 148,20±6,37 mg/dL; p < 0,05). Além disso, foi encontrado aumento na taxa HDL/colesterol total (pré: 0,22±0,03 vs pós: 0,27±0,06; p < 0,05). Os resultados indicam que a temporada de basquetebol profissional pode induzir alterações na concentração de LDL-colesterol, de colesterol total e na taxa HDL/colesterol total, sugerindo um efeito modulador sobre o perfil lipídico de jogadores profissionais de basquetebol após uma temporada de 4 meses

    Hypothalamic inflammation is reversed by endurance training in anorectic-cachectic rats

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    <p>Abstract</p> <p>Aim</p> <p>We tested the effects of a cancer cachexia-anorexia sydrome upon the balance of anti and pro-inflammatory cytokines in the hypothalamus of sedentary or trained tumour-bearing (Walker-256 carcinosarcoma) rats.</p> <p>Methods</p> <p>Animals were randomly assigned to a sedentary control (SC), sedentary tumour-bearing (ST), and sedentary pair-fed (SPF) groups or, exercised control (EC), exercised tumour-bearing (ET) and exercised pair-fed (EPF) groups. Trained rats ran on a treadmill (60%VO<sub>2max</sub>) for 60 min/d, 5 days/wk, for 8 wks. We evaluated food intake, leptin and cytokine (TNF-α, IL1β) levels in the hypothalamus.</p> <p>Results</p> <p>The cumulative food intake and serum leptin concentration were reduced in ST compared to SC. Leptin gene expression in the retroperitoneal adipose tissue (RPAT) was increased in SPF in comparison with SC and ST, and in the mesenteric adipose tissue (MEAT) the same parameter was decreased in ST in relation to SC. Leptin levels in RPAT and MEAT were decreased in ST, when compared with SC. Exercise training was also able to reduce tumour weight when compared to ST group. In the hypothalamus, IL-1β and IL-10 gene expression was higher in ST than in SC and SPF. Cytokine concentration in hypothalamus was higher in ST (TNF-α and IL-1β, p < 0.05), compared with SC and SPF. These pro-inflammatory cytokines concentrations were restored to control values (p < 0.05), when the animals were submitted to endurance training.</p> <p>Conclusion</p> <p>Cancer-induced anorexia leads towards a pro-inflammatory state in the hypothalamus, which is prevented by endurance training which induces an anti-inflammatory state, with concomitant decrease of tumour weight.</p
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