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91.
While much is known about the metabolism of exogenous nutrients such as glucose, lactate, pyruvate, amino acids by oocytes and pre-implantation mammalian embryos, the role of endogenous stores, particularly lipid, has been largely overlooked. The presence of lipid within oocytes and early embryos has been long known, and comparisons between species indicate that the amounts and types of lipid present vary considerably. Large amounts of intracellular lipid can compromise the success of cryopreservation and the removal of such lipid has been the subject of considerable effort. In this review, we present evidence that strongly suggests a metabolic role for lipid, specifically with regard to energy provision, in the late-stage oocyte and the pre-implantation embryo. We focus initially on oxygen consumption as a global indicator of metabolic activity, before reviewing different approaches that either have been designed to investigate directly, or have revealed indirectly the role of endogenous lipid in energy generation. These fall under five headings: (i) fatty acid oxidation; (ii) inhibition of triglyceride oxidation; (iii) culture in the absence of exogenous substrates; (iv) cytoplasmic organization; and (v) delipidation. On the basis of the data derived from these studies, we conclude that there is strong evidence for the utilization of endogenous lipid as an energy substrate by oocytes and early embryos. 相似文献
92.
BN Lourenço G Marchioli W Song RL Reis CA van Blitterswijk M Karperien A van Apeldoorn JF Mano 《Biointerphases》2012,7(1-4):46
Surface wettability and topography are recognized as critical factors influencing cell behavior on biomaterials. So far only few works have reported cell responses on surfaces exhibiting extreme wettability in combination with surface topography. The goal of this work is to study whether cell behavior on superhydrophobic surfaces is influenced by surface topography and polymer type. Biomimetic superhydrophobic rough surfaces of polystyrene and poly(L-lactic acid) with different micro/nanotopographies were obtained from smooth surfaces using a simple phase-separation based method. Total protein was quantified and showed a less adsorption of bovine serum albumin onto rough surfaces as compared to smooth surfaces of the same material. The mouse osteoblastic MC3T3-E1 cell line and primary bovine articular chondrocytes were used to study cell attachment and proliferation. Cells attached and proliferate better in the smooth surfaces. The superhydrophobic surfaces allowed cells to adhere but inhibited their proliferation. This study indicates that surface wettability, rather than polymer type or the topography of the superhydrophobic surfaces, is a critical factor in determining cell behavior. 相似文献
93.
Medium Light and Medium Roast Paper-Filtered Coffee Increased Antioxidant Capacity in Healthy Volunteers: Results of a Randomized Trial 总被引:1,自引:1,他引:0
TA Corrêa MP Monteiro TM Mendes DM Oliveira MM Rogero CI Benites CG Vinagre BM Mioto D Tarasoutchi VL Tuda LA César EA Torres 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(3):277-282
We compared the effects of medium light roast (MLR) and medium roast (MR) paper-filtered coffee on antioxidant capacity and lipid peroxidation in healthy volunteers. In a randomized crossover study, 20 volunteers consumed 482?±?61?ml/day of MLR or MR for four weeks. Plasma total antioxidant status (TAS), oxygen radical absorbance capacity (ORAC), oxidized LDL and 8-epi-prostaglandin F2α, erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activity were measured at baseline and after the interventions. MLR had higher chlorogenic acids-(CGA; 334?mg/150?mL) and less caffeine (231?mg/150?ml) than MR had (210 and 244?mg/150?ml, respectively). MLR also had fewer Maillard reaction products (MRP) than MR had. Compared with baseline, subjects had an increase of 21 and 26?% in TAS, 13 and 13?% in CAT, 52 and 75?% in SOD, and 62 and 49?% in GPx after MLR and MR consumption (P?0.001), respectively. ORAC increased after MLR (P?=?0.004). No significant alteration in lipid peroxidation biomarkers was observed. Both coffees had antioxidant effects. Although MLR contained more CGA, there were similar antioxidant effects between the treatments. MRP may have contributed as an antioxidant. These effects may be important in protecting biological systems and reducing the risk of diseases related to oxidative stress. 相似文献
94.
Path analysis for selection of drought tolerant sugarcane genotypes through physiological components
Paulo Pedro da Silva Lailton SoaresJoão Gomes da Costa Luciana da Silva VianaJúlio César Farias de Andrade Eduardo Rebelo GonçalvesJoão Messias dos Santos Geraldo Veríssimo de Souza BarbosaVelber Xavier Nascimento Adriana Reis TodaroAlessandro Riffel Maria Fatima Grossi-de-SaMárcio Henrique Pereira Barbosa Antônio Euzébio Goulart Sant’AnaCícero Eduardo Ramalho Neto 《Industrial Crops and Products》2012,37(1):11-19
Water deficit is among the main environmental factors limiting agricultural productivity of sugarcane in Northeast Brazil by affecting virtually every aspect of plant growth, with consequent reduction of the agro-industrial productivity of this crop. This study aimed to use path analysis to evaluate the physiological components of sugarcane under two water conditions, with photosynthesis as the basic variable, in order to obtain subsidies that can help the genetic breeding of this crop by selection of superior clones with drought tolerance. The experiment was carried out in a greenhouse with a completely randomized experimental design, 4 × 2 factorial arrangements (four sugarcane genotypes × two soil moisture regimes: control, with 80-100% available water and stressed, with 0-20% water available) and with four replications. Each plot consisted of one pot with 12 kg of substrate containing one plant. Treatments were maintained at a humidity close to field capacity with daily replacement of the evapotranspired water with a water supply for 66 days of cultivation for treatments under stress. Evaluations were conducted on the fourth day after severe water stress at 70 days of cultivation. Data from nine physiological variables were considered, with six of these being used in the model after exclusion of those that were contributing to multicollinearity. Variables used in path analysis were enough to explain the variation found in photosynthesis under both water conditions. Stomatal conductance, transpiration and the SPAD index should be considered as a priority in breeding programs for sugarcane aiming to get more productive and tolerant genotypes to water stress, and selection indexes should be used with due consideration of these variables to promote gains in photosynthesis. 相似文献
95.
M.C. Leal C. Nunes S. Kempf A. Reis T.L. da Silva J. Serdio D.F.R. Cleary R. Calado 《Aquaculture Nutrition》2013,19(5):818-826
Sea anemones of the genus Aiptasia are used as biological models for research and as a prey for the culture of the highly priced ornamental nudibranch Aeolidiella stephanieae. Symbiotic Aiptasia display a remarkable trophic plasticity, being able to fulfil their energetic demands heterotrophically and autotrophically. Consequently, they display a highly variable fatty acid (FA) profile. The objective of the present study was to analyse how light regime (12 h light : 12 h dark versus 24 h darkness), water temperature (22 versus 26 °C) and diet (Artemia nauplii versus enriched Artemia metanauplii) affect the FA composition of A. pallida. The FA profile of wild specimens was also analysed. The dominant FAs of cultured A. pallida were 16:0, 18:1n‐9 and 22:6n‐3. Higher FA levels were recorded when anemones were exposed to light, with this factor explaining the largest amount of variation in the composition of FA profiles. Cultured A. pallida that best mimicked wild anemones were obtained when using a regular light regime, Artemia metanauplii and 22 °C water temperature. Higher FA levels were obtained at a higher temperature and by providing nauplii to cultured anemones. The present study also indicated that A. pallida has the potential to recycle nutrients in marine aquacultures. 相似文献
96.
Marcos Rafael Nanni Everson Cezar Guilherme Fernando Capristo Silva Anderson Antonio da Silva Gualberto 《Archives of Agronomy and Soil Science》2018,64(5):682-695
New techniques and improvements are required to quantify soil’s chemical and physical properties on production environment, reducing environmental impacts and minimizing soil analysis time. The aim of this study is to evaluate the possibility to estimate the content of silt, sand, clay, total iron and organic matter in soils formed by different lithologies in Parana State, Brazil, using VIS-NIR spectrum associated with Partial Least Square Regression (PLSR). 200 soil samples were collected in an area formed by Lixisols, Cambisols, Ferralsols, Arenosols and Nitisols in a depths of 0–0.2 and 0.2–0.8 m. Spectral readings were obtained in laboratory by FieldSpec 3 JR sensor. The spectral curves of the samples were correlated to the attributes through PLSR. The results obtained for sand in prediction were better when compared to the other attributes, presenting R2 = 0.90, r = 0.95 and RPD = 2.3. Clay and total iron presented satisfactory results, mainly for RPD values, which were above 2.4. Based on the results, it can be concluded that the PLSR technique associated with the spectral response of the soils, was able to estimate sand, clay and total iron with accuracy in a region formed by reworked materials, derived from several lithologies. 相似文献
97.
Márcio Fléquisson Alves Miranda Maria Betânia Galvão dos Santos Freire Brivaldo Gomes Almeida Fernando José Freire Luiz Guilherme Medeiros Pessoa 《Archives of Agronomy and Soil Science》2018,64(9):1207-1221
This study aimed to evaluate the use of phytoremediation and soil conditioners in the recovery of physical attributes of a saline-sodic Fluvic Neossol in Brazil Northeast. The applied treatments were: Atriplex nummularia L., as phytoremediation plant, due to its ability to extract salts from the soil; organic conditioners, such as bovine and sheep manure; gypsum and polymer, as chemical conditioners. Samples with preserved structure were collected at the time of the experiment installation and 18 months after in the layers 0–10 cm and 10–30 cm. The analyzed attributes were: water dispersed clay, dispersion index, bulk density, penetration resistance, soil porosity, and saturated hydraulic conductivity. The use of sheep manure, gypsum and polymer promoted an increase in saturated hydraulic conductivity in the 0–10 cm layer from 4.51 to 16.37 cm day?1, 11.26 to 23.95 cm day?1 and 7.24 to 22.77 cm day?1, respectively. Gypsum increased the macroporosity in the superficial layer by 42.6%. Atriplex and polymer were more efficient at reducing soil penetration resistance. The polymer was more efficient at improving the physical properties. However, it is necessary to consider phytoremediation with Atriplex as a more sustainable alternative that can still be used as complementary fodder in animal feed. 相似文献
98.
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
99.
Adriano Reis LUCHETA Fabiana de SOUZA CANNAVAN Siu Mui TSAI Eiko Eurya KURAMAE 《土壤圈》2017,27(5):832-845
Amazonian Dark Earth (ADE) is a highly fertile soil of anthropogenic origin characterized by high levels of charred black carbon (BC).It is considered a model of fertility;however,knowledge on the fungal community structure and diversity inhabiting ADE and its BC particles is scarce.Fungal community structure and diversity of ADE and its BC from four sites under different land uses (three agricultural systems and a secondary pristine forest) in the Brazilian Central Amazon were evaluated by 18S rRNA gene pyrosequencing.Fungal communities in ADE and BC were dissimilar and showed differential abundances of fungal operational taxonomic units (OTUs).Estimated fungal species richness (abundance-based coverage estimate and Chao-1 index) and diversity estimators (Shannon and Simpson's reciprocal indices) were higher in ADE than in BC in all agricultural areas.No differences were observed in those parameters in ADE and BC samples from the secondary forest.Pezizomycotina fungi and OTUs assigned to Cordyceps confragosa,Acremonium vitellinum,Camarops microspora,and Hirsutella rhossiliensis were more abundant in BC particles than in ADE.These findings represent a breakthrough in our understanding of fungal communities in BC particles from ADE,and will be valuable in future studies considering biochar application in soil. 相似文献
100.
Sato José Paulo Hiroji Gava Danielle Schaefer Rejane Cantão Maurício Egídio Ciacci-Zanella Janice Reis de Barcellos David Emilio Santos Neves 《Tropical animal health and production》2017,49(5):1071-1075
Tropical Animal Health and Production - Porcine circovirus type 2 (PCV2) has been identified in pig population in Brazil since 2000, but scarce studies involving wild boars with PCV2 infection are... 相似文献