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181.
The coenzyme Q10 (CoQ10) is a potent antioxidant with critical protection role against cell oxidative stress, caused by the mitochondrial dysfunction. This study evaluated the effects of CoQ10 supplementation to in vitro maturation (IVM) or embryo culture media on the maturation, fertilization and subsequent embryonic development of pig oocytes and embryos. Maturation (Experiment 1) or embryo culture (Experiment 2) media were supplemented with 0 (control), 10, 25, 50 and 100 μM CoQ10. The addition of 10–50 μM CoQ10 to the IVM medium did not affect the percentage of MII oocytes nor the fertilization or the parameters of subsequent embryonic development. Exogenous CoQ10 in the culture medium neither did affect the development to the 2–4‐cell stage nor rates of blastocyst formation. Moreover, the highest concentration of CoQ10 (100 μM) in the maturation medium negatively affected blastocyst rates. In conclusion, exogenous CoQ10 supplementation of maturation or embryo culture media failed to improve the outcomes of our in vitro embryo production system and its use as an exogenous antioxidant should not be encouraged.  相似文献   
182.
Antioxidants have been widely used during in vitro production to decrease the negative effect of reactive oxygen species. It was reported that the complex resveratrol–methyl β‐cyclodextrin (RV ‐CD ) improves resveratrol's stability and bioavailability and increases its antioxidant activity. This study evaluates the effect of RV ‐CD during in vitro oocyte maturation (IVM ) or in vitro embryo culture (IVC ) on developmental competence and quantitative changes in gene expression of developmental important genes. In experiment 1, RV ‐CD was added to IVM media and maturation level, embryo development and oocytes, cumulus cells, and blastocysts gene expression by RT ‐qPCR were examined. In experiment 2, presumptive zygotes were cultured in SOF supplemented with RV ‐CD and embryo development and blastocysts gene expression by RT ‐qPCR were studied. A group without RV ‐CD (control?) and a group with cyclodextrin (control+) were included. No differences were found in cleavage rate or blastocyst yield between groups. However, the expression of LIPE was higher in blastocysts derived from oocytes treated with resveratrol compared with control groups (<  .05). Blastocysts produced by IVC with resveratrol showed that RV ‐CD could modify the expression of genes related to lipid metabolism (CYP 51A1 , PNPLA 2 and MTORC 1 ) compared with control groups (p  < .05). RV ‐CD in the IVM and IVC media could reduce accumulated fat by increasing lipolysis and suppressing lipogenesis of blastocysts.  相似文献   
183.
Florfenicol (FF) is employed in fish farms to contest or prevent bacterial infections. However, this pharmaceutical may produce reactive oxygen species that may cause biochemical changes in antibiotic-treated fish. The aim of this study was to evaluate the effect of FF on Rainbow Trout Oncorhynchus mykiss treated for 10 d with 7.5 and 15 mg/kg FF followed by a withdrawal period of 5 d. Superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione S-transferase, glyoxalase I and glyoxalase II, total glutathione, lactic dehydrogenase, and alkaline phosphatase were investigated in the livers of treated and untreated fish. A general impairment of antioxidant enzymes and metabolic indicators was measured in FF-treated Rainbow Trout. Onset of oxidative damage may have occurred during the antibiotic treatment as a consequence of the effect of FF toxicity at mainly the highest dose. Nevertheless, the rise in levels of total glutathione and glutathione S-transferase even after the withdrawal period may shield the antibiotic-mediated oxidative processes.

Received December 22, 2015; accepted May 26, 2016 Published online October 28, 2016  相似文献   

184.
Data from seven generations of a divergent selection experiment designed for environmental variability of birth weight were analysed to estimate genetic parameters and to explore signs of selection response. A total of 10 783 birth weight records from 638 females and 1127 litters in combination with 10 007 pedigree records were used. Each record of birth weight was assigned to the mother of the pup in a heteroscedastic model, and after seven generations of selection, evidence of success in the selection process was shown. A Bayesian analysis showed that success of the selection process started from the first generation for birth weight and from the second generation for its environmental variability. Genetic parameters were estimated across generations. However, only from the third generation onwards were the records useful to consider the results to be reliable. The results showed a consistent positive and low genetic correlation between the birth weight trait and its environmental variability, which could allow an independent selection process. This study has demonstrated that the genetic control of the birth weight environmental variability is possible in mice. Nevertheless, before the results are applied directly in farm animals, it would be worth confirming any other implications on other important traits, such as robustness, longevity and welfare.  相似文献   
185.
Microbial processes have shown promise for the remediation of uranium and nitrate in groundwater impacted by uranium mine tailings. This study investigated the inhibitory impact of uranium(VI) towards different microbial populations in anaerobic biofilms, including methanogenic, denitrifying, and uranium-reducing microorganisms, which are commonly found at uranium bioremediation sites. Results of batch activity bioassays indicated a very distinct level of toxicity depending on the targeted microbial community. U(VI) caused severe inhibition of acetoclastic methanogenesis as indicated by a 50?% inhibiting concentration (IC50) of only 0.16?mM. Denitrifying populations were also impacted by uranium, but their sensitivity depended on the electron donor utilized. Sulfur-oxidizing denitrifiers were the least affected (IC50 for denitrification activity?=?0.32?mM), followed by H2- and acetate-utilizing denitrifiers (IC50 of 0.20 and 0.15?mM, respectively). In contrast, exposure to U(VI) concentrations up to 1.0?mM did not inhibit the rate of U(VI) bioreduction with H2 as electron donor in the presence or absence of nitrate. On the contrary, a considerable increase in the uranium-reducing activity of the denitrifying and methanogenic mixed cultures was observed with increasing uranium concentrations. The results suggest that microorganisms responsible for U(V) reduction could tolerate much higher uranium concentrations compared to the other microbial populations assayed.  相似文献   
186.
The adsorption behavior of denim blue from aqueous solutions in column systems, using both carbonaceous material and Fe-zeolitic tuff (Fe-Z), was determined. The breakthrough data obtained for denim blue adsorption were fitted to the empty-bed contact time, Bohart?CAdams, Thomas, and Yoon?CNelson models. The parameters such as breakthrough and saturation times, bed volumes, kinetic constants, adsorption capacities, and adsorbent usage rates (AUR) were determined. The results show that the breakthrough time increases proportionally with increasing bed height, but it decreases as the kinetic constant increases. The adsorption capacity for denim blue for carbonaceous material was higher than Fe-Z. AUR was lower for carbonaceous material than Fe-Z. The results indicated that the carbonaceous material from pyrolysis of sewage sludge is a good adsorbent for denim blue removal.  相似文献   
187.
Leguminous trees have a potential for phytoremediation of oil-contaminated areas for its symbiotic association with nitrogen-fixing bacteria and arbuscular mycorrhizal fungi (AMF). This study selects leguminous tree associated with symbiotic microorganisms that have the potential to remediate petroleum-contaminated soil. Seven species of trees were tested: Acacia angustissima, Acacia auriculiformis, Acacia holosericea, Acacia mangium, Mimosa artemisiana, Mimosa caesalpiniifolia, and Samanea saman. They were inoculated with AMF mix and nitrogen-fixing bacteria mix and cultivated over five oil levels in soils, with five replicates. The decreasing of total petroleum hydrocarbons (TPH) values occurred especially with S. saman and its symbiotic microorganisms on highest oil soil contamination. Despite the large growth of A. angustissima and M. caesalpiniifolia on the highest level of oil, these species and its inoculated microorganisms did not reduce the soil TPH. Both plants were hydrocarbon tolerant but not able to remediate the polluted soil. In contrast were significative hydrocarbon decrease with M. artemisiana under high oil concentrations, but plant growth was severely affected. Results suggest that the ability of the plants to decrease the soil concentration of TPH is not directly related to its growth and adaptation to conditions of contamination, but the success of the association between plants and its symbionts that seem to play a critical role on remediation efficiency.  相似文献   
188.
The genetic variability of high molecular weight glutenin subunits (HMWGS) composition at the Glu-1 loci in bread wheat (Triticum aestivum L.) was studied electrophoretically using the SDS–PAGE in 3,470 individuals representing 159 populations originated from the Canary Islands (Spain), the Archipelago of Madeira (Portugal) and the continental Portugal. A total of 25 alleles were detected, resulting in 69 different allele combinations. The geographical distribution of the high molecular weight glutenin alleles confirms historical data regarding circulation of wheat germplasm between the Iberian Peninsula and Madeira and between Madeira and the Canary Islands and vice versa.  相似文献   
189.
It has been reported for many soils that maize (Zea mays L.) has a higher soil‐P critical level than soybean (Glycine max L.) and sunflower (Helianthus annuus L). The objective of this work was to compare the rhizosphere P depletion in these three species in order to investigate if they differ in their capacity to acquire soil P. Sequential P fractionation and pH were determined in rhizosphere and nonrhizosphere soil samples from field and greenhouse experiments. Neither sunflower (the species with highest rhizosphere acidification) nor soybean or maize showed a significant relationship between P depletion and rhizosphere pH. The labile P fraction and the NaOH‐Pi fraction had lower values in the rhizosphere than in the bulk soil in 38% and 77% of the studied cases, respectively. Sunflower and especially maize presented a more intense Pi depletion than soybean. The comparison between sunflower and maize revealed that neither of them took a clear advantage over the other in terms of P depletion. Rhizosphere Pi depletion was associated with the amount of P acquired by the plants. We conclude that the accessibility to different P pools does not explain the differences in soil‐P critical levels among the three species.  相似文献   
190.
Five-membered rings are of particular interest, due to their presence in some of the most common molecules in chemistry and biology. Despite their apparent simplicity, the structural resolution of these rings is complex, due to their inherent conformational flexibility. Here, we describe an application of a recently reported simple and efficient NMR protocol based on the measurement of spin-spin coupling constants to achieve the challenging relative configurations of five new halogenated C15 tetrahydrofuranyl-acetogenins, marilzafurollenes A–D (1–4) and 12-acetoxy-marilzafurenyne (5), isolated from the red alga, Laurencia marilzae. Although DFT chemical shift calculations were used to connect remote stereocenters, the NMR-based approach seems advantageous over computational techniques in this context, as the presence of halogens may interfere with reliable calculations.  相似文献   
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