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CA Meza‐Herrera TT Ross DM Hallford DE Hawkins A Gonzalez‐Bulnes 《Reproduction in domestic animals》2010,45(4):723-728
The effects of supplemented protein level (PL) during the periconceptional period and their interaction with body condition were evaluated in sheep. Multiparous Rambouillet ewes (n = 12) received two PL of rumen undegradable protein (UIP) during a 30‐day pre‐mating and 15‐day post‐mating period: low [LPL, 24% crude protein (CP), 14 g UIP and 36 g/CP animal/day] and high [HPL, 44% CP, 30 g UIP and 50 g/CP animal/day]. While ovulation rate (OR) did not differ between treatments (1.6 ± 0.5, mean ± SEM), a lower fertility rate, a decreased embryo number and a reduced uterine pH (UpH) was observed in the HPL group (p < 0.05), irrespective of BC. Luteal tissue weight, volume and progesterone secretion did not differ among treatments. Sheep with lower UpH also had lower conceptus weight (Cwt; p < 0.05, r = 0.65) and conceptuses with lower mass tended to secrete less INF‐τ and IGF‐1, and the correspondent endometrial explants had a higher basal PGF2α release. Current study indicates that high protein diets during the periconceptional period in sheep modify uterine and embryonic relationships, increasing early pregnancy losses and inducing embryo growth retardation. Surviving embryos were affected by weight reductions, which could compromise later foetal growth and birth weight. Results evidence the key role of a balanced diet in reproductive success and indicate that the quality and nutrient composition of the maternal diet are essential for an adequate establishment of pregnancy, having paramount effects on the interplay of the embryo and the uterus. 相似文献
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Recently, four external invertase isoforms (EINV1, EINV2, EINV3, and EINV4) have been isolated from S. cerevisiae. However, there is nothing known about their structural features and thermodynamics of unfolding. Since this information is essential for understanding their functioning at the molecular level as well as applicable in the food industry, we investigated guanidinium-chloride induced structural changes of the isoforms by CD and fluorescence spectroscopy. The resulting unfolding curves measured for each isoform at different temperatures were described simultaneously by a reversible two-state model to obtain the corresponding thermodynamic parameters. Here, we show that they are different for different isoforms and demonstrate that they correlate with the surface charge density of the native isoforms which follows the order EINV1 < EINV2 < EINV3 < EINV4. It appears that at physiological temperatures the thermodynamic stability of the isoforms follows the same order, while above 55 °C, the order is the opposite EINV1 > EINV2 > EINV3 ≈ EINV4. This suggests that increasing the efficiency of the food industry processes involving invertase would require the application of EINV3 and/or EINV4 at physiological temperatures and EINV1 at elevated temperatures. 相似文献
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Castino R Pucer A Veneroni R Morani F Peracchio C Lah TT Isidoro C 《Journal of agricultural and food chemistry》2011,59(8):4264-4272
Malignant glioblastoma represents a challenge in the chemotherapy of brain tumors, because of its aggressive behavior characterized by chemoresistance, infiltrative diffusion, and high rate of recurrence and death. In this study, we used cultured human U87MG cells and primary human glioblastoma cultures to test the anticancer properties of resveratrol (RV), a phytoalexin abundantly present in a variety of dietary products. In U87MG cells, 100 μM RV elicited cell growth arrest by 48 h and bax-mediated cell toxicity by 96 h and greatly limited cell migration and invasion through matrigel. Both in U87MG cells and in primary glioblastoma cultures, the chronic administration of RV (100 μM for up to 96 h) decreased the expression of nestin (a brain (cancer) stem cells marker) but increased that of glial acidic fibrillary protein (a mature glial cell marker) and of βIII-tubulin (a neuronal differentiation marker). Chronic treatment with RV increased the proportion of cells positive for senescence-associated β-galactosidase activity. This is the first report showing the ability of RV to induce glial-like and neuronal-like differentiation in glioblastoma cells. The beneficial effects of chronic RV supplementation lasted up to 96 h after its withdrawal from the culture medium. The present findings support the introduction of pulsed administration of this food-derived molecule in the chemotherapy regimen of astrocytomas. 相似文献
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Metka Novak Andreja Urbanek Krajnc Ljerka Lah Neja Zupanec Nada Kraševec Mitja Križman Joerg Bohlmann Radovan Komel 《European Journal of Forest Research》2014,133(4):573-583
Among the most devastating pests of Norway spruce (Picea abies) are the European spruce bark beetle (Ips typographus) and the associated pathogenic blue-stain fungus Ceratocystis polonica. Following attack and colonization, the beetle and the fungus must cope with induced host chemical defenses, such as monoterpenes that are generally thought to be toxic to both symbionts. The goal of this study was to better understand the response of Norway spruce following C. polonica inoculation at low density that does not overwhelm the tree and to identify monoterpenes mobilized toward the fungus. We inoculated healthy mature trees and monitored monoterpene profiles 2, 3, and 5 months post-inoculation. We also exposed three different C. polonica strains to the most abundant or significantly up-regulated monoterpenes to determine differences in monoterpene toxicity and resistance among strains. Total monoterpene levels, including limonene, were increased at 2 and 3 months after inoculation and had dropped after 5 months. In in vitro assays, all monoterpenes were inhibitory to C. polonica. Limonene and β-pinene were the most potent inhibitors of fungal growth. The extent of inhibition varied between the three strains tested. These results showed a defense response of Norway spruce to C. polonica, in which limonene may play a critical role in inhibiting the spread of the fungus. We also showed that differences between strains of C. polonica must be taken into account when assessing the role of the fungus in this bark beetle–symbiont system. 相似文献
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