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51.
Trypanocidal Action of (?)-Elatol Involves an Oxidative Stress Triggered by Mitochondria Dysfunction
Vania Cristina Desoti Danielle Lazarin-Bid��ia Daniela Bueno Sudatti Renato Crespo Pereira Antonio Alonso Tania Ueda-Nakamura Benedito Prado Dias Filho Celso Vataru Nakamura Sueli de Oliveira Silva 《Marine drugs》2012,10(8):1631-1646
Natural compounds have shown good potential for the discovery of new chemotherapeutics for the treatment of Chagas’ disease. Recently, our group reported the effective trypanocidal activity of (−)-elatol, extracted from the red macroalgae Laurencia dendroidea present in the Brazilian coast against Trypanosoma cruzi. However, the mechanism of action of this compound has remained unclear. There are only hypotheses concerning its action on mitochondrial function. Here, we further investigated the mechanisms of action of (−)-elatol on trypomastigotes of T. cruzi. For this, we evaluated some biochemical alterations in trypomastigotes treated with (−)-elatol. Our results show that (−)-elatol induced depolarization of the mitochondrial membrane, an increase in the formation of mitochondrial superoxide anion and loss of cell membrane and DNA integrity. Additionally, (−)-elatol induced formation of autophagic vacuoles and a decrease in cell volume. All together, these results suggest that the trypanocidal action of (−)-elatol involves multiple events and mitochondria might be the initial target organelle. Our hypothesis is that the mitochondrial dysfunction leads to an increase of ROS production through the electron transport chain, which affects cell membrane and DNA integrity leading to different types of parasite death. 相似文献
52.
The protective effect of dietary L-carnitine supplementation was accessed in turbot (Scophthalmusmaximus) challenged with Streptococcus parauberis. Infected fish fed 240mg L-carnitine showed significantly (P < 0.01) higher survival (78%) than infected fish fed 40mg L-carnitine (11%). When dietary L-carnitine supplementation was suspended, a significant increase in mortality was observed in infected fish. The present report documents that dietary L-carnitine fed on a continuous basis may act as an immunostimulant in turbot. 相似文献
53.
Vanessa Dias Capriles Eveline Lopes Almeida Reinaldo Eduardo Ferreira Jos Alfredo Gomes Arêas Caroline Joy Steel Yoon Kil Chang 《Cereal Chemistry》2008,85(5):614-618
The sum of wheat flour and corn starch was replaced by 10, 20, or 30% whole amaranth flour in both conventional (C) and reduced fat (RF) pound cakes, and the effects on physical and sensory properties of the cakes were investigated. RF presented 33% fat reduction. The increasing amaranth levels darkened crust and crumb of cakes, which decreased color acceptability. Fresh amaranth‐containing cakes had similar texture characteristics to the controls, evaluated both instrumentally and sensorially. Sensory evaluation revealed that replacement by 30% amaranth flour decreased C cakes overall acceptability scores, due to its lower specific volume and darker color. Amaranth flour levels had no significant effect on overall acceptability of RF cakes. Hence, the sum of wheat flour and corn starch could be successfully replaced by up to 20% amaranth flour in C and up to 30% in RF pound cakes without negatively affecting sensory quality in fresh cakes. Moisture losses for all the cakes were similar, ≈1% per day during storage. After six days of storage, both C and RF amaranth‐containing cakes had higher hardness and chewiness values than control cakes. Further experiments involving sensory evaluation during storage are necessary to determine the exact limit of amaranth flour replacement. 相似文献
54.
Guimes Rodrigues Filho Sabrina Dias RibeiroCarla da Silva Meireles Leandro Gustavo da SilvaReinaldo Ruggiero Moacir Fernandes Ferreira JuniorDaniel Alves Cerqueira Rosana Maria Nascimento de AssunçãoMara Zeni Patricia Polleto 《Industrial Crops and Products》2011,33(3):566-571
Cellulose acetate is one of the components employed in drug controlled-release systems in the form of membranes. The aim of this study was to examine the controlled-release of doxycycline employing cellulose acetate symmetric and asymmetric membranes as matrices. The cellulose triacetate was produced from sugarcane bagasse through a homogeneous acetylation reaction, using acetic acid as the solvent, acetic anhydride as the acetylating agent and sulfuric acid as the catalyst. The viscosity average molecular weight of the cellulose acetate produced was 39,000 g mol−1. The symmetric membranes were produced using a system solvent of dichloromethane/ethanol (9:1, v/v) and the asymmetric membranes were produced from the same solvent system and 10% of water. For the formulation of both, 5% of doxycycline was used. The membranes were characterized by thermal analysis (DSC and TGA) and scanning electron microscopy SEM. The release of doxycycline through cellulose triacetate matrices was examined using spectrophotometric analysis in the ultraviolet-visible region, at 275 nm. The results revealed that asymmetric membranes release 80% of the drug in 100 min, while symmetric membranes release 14% of the drug during the same time interval. 相似文献
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57.
Samuel Luiz Fioreze João Paulo Costa Carneiro Daniela Dias Pinto João Domingos Rodrigues 《Journal of plant nutrition》2017,40(18):2602-2610
We characterized the pollination and fecundation times in soybean flowers and evaluated the effects of kinetin and calcium applications on physiological and productive traits of soybean plants during the reproductive stage. The anatomical study of flowers of eight soybean cultivars showed that fecundation occurred in closed flowers with visible petals, which presented embryo in the first cell divisions. These results indicate that fertilizers and growth regulation applications should be performed before flower opening, which is different from the current recommendation. Foliar applications of kinetin and calcium between the floral bud and full flowering stages did not affect carbon dioxide (CO2) assimilation, yield components and final yield. The results obtained in this research showed the lack of viability of foliar application of calcium and kinetin in order to increase pod set and number of seeds per plant in soybean crop. 相似文献
58.
Glaydson S. dos Reis Matthew A. Adebayo Carlos H. Sampaio Eder C. Lima Pascal S. Thue Irineu A. S. de Brum Silvio L. P. Dias Flavio A. Pavan 《Water, air, and soil pollution》2017,228(1):33
Sludge-derived activated carbons (ACs) were prepared by conventional heating and microwave pyrolysis. The ACs were characterized using several analytical and functional techniques and used for removal of six phenolic compounds from aqueous solutions. The adsorbents exhibited similar features and possessed hydrophobic surfaces. The ACs were assigned mesoporous materials, with specific surface areas of up to 641 and 540 m2 g?1 for CAC-500 and MAC-980, respectively. The preliminary results indicated that phenol removal onto the ACs increased in the order: m-cresol?<?phenol?<?o-cresol?<?2-chrorophenol?<?2-nitrophenol?<?hydroquinone. Hydroquinone exhibited the highest adsorption capacity and was chosen to continue the remaining part of the experimental work—kinetic and isothermal studies. The adsorption kinetic and isotherm data were well described by the Avrami fractionary order and Redlich–Peterson models, respectively. The maximum amounts (Q max) of hydroquinone adsorbed at 25 °C were too high, reaching 1218.3 and 1202.1 mg g?1 for CAC-500 and MAC-980, respectively. The mechanism of adsorption was proposed in this work, and it was suggested that donor–acceptor complex and π–π interactions play major roles in the adsorption process. The adsorbents were also tested on simulated effluents. The two ACs displayed good efficiency for the treatment of industrial simulated effluents. 相似文献
59.
Cláudio Eduardo Silva Freitas Eduardo Robson Duarte Dorismar David Alves Isabel Martinele Marta D’Agosto Franciane Cedrola Angélica Alves de Moura Freitas Franklin Delano dos Santos Soares Makenzi Beltran 《Tropical animal health and production》2017,49(4):807-812
A ciliate protozoa suppression can reduce methane production increasing the energy efficiency utilization by ruminants. The physicochemical characteristics of rumen fluid and the profile of the rumen protozoa populations were evaluated for sheep fed banana leaf hay in replacement of the Cynodon dactylon cv. vaqueiro hay. A total of 30 male sheep were raised in intensive system during 15 days of adaptation and 63 days of experimental period. The animals were distributed in a completely randomized design that included six replicates of five treatments with replacement levels (0, 25, 50, 75, and 100%) of the grass vaquero for the banana leaf hay. Samples of fluid were collected directly from the rumen with sterile catheters. Color, odor, viscosity, and the methylene blue reduction potential (MBRP) were evaluated and pH estimated using a digital potentiometer. After decimal dilutions, counts of genus protozoa were performed in Sedgewick Rafter chambers. The averages of pH, MBRP, color, odor, and viscosity were not influenced by the inclusion of the banana leaf hay. However, the total number of protozoa and Entodinium spp. population significantly decreased at 75 and 100% inclusions of banana leaf hay as roughage. 相似文献
60.
Amanda B. Dias Carmen M.O. MüllerFábio D.S. Larotonda João B. Laurindo 《Journal of Cereal Science》2010
Rice flour is a starchy material with low-cost, because it can be produced from rice that is broken during processing. The aim of this study was to develop biodegradable films based on rice starch and rice flour, and to characterize their physicochemical, microscopic and mechanical properties. Films from rice starch and rice flour were prepared by casting, with glycerol or sorbitol as plasticizer. SEM analysis of starch and flour films revealed compact structures. Rice flour films prepared in the present work have similar mechanical properties to those of starch based films. However, their water vapor permeabilities are two times higher than those of starch based films. Films with sorbitol were less permeable to water and more rigid, while films with glycerol are more plasticized and have poorer water vapor barrier properties. Therefore, preparing edible films from rice flour is a new alternative for using this raw material, which is sometimes much cheaper than commercial starches. 相似文献