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91.
Monteiro MV Bevilaqua CM Morais SM Machado LK Camurça-Vasconcelos AL Campello CC Ribeiro WL Mesquita Mde A 《Veterinary parasitology》2011,182(2-4):259-263
The aim of this study was to evaluate the anthelmintic activity of hexane (HE), ethyl acetate (EA) and ethanol (EE) extracts obtained from the seeds of Jatropha curcas using the egg hatch inhibition assay (EHA) and the artificial larval exsheathment inhibition assay (LEIA). For the egg hatch assay, HE, EA and EE were used in concentrations of 3.12, 6.25, 12.5, 25 and 50 mg ml(-1), accompanied by a negative control (5% Tween 80) and a positive control (0.025 g ml(-1) thiabendazole). In LEIA, the extracts were tested at a concentration of 1000 μg ml(-1), accompanied by a negative control (PBS). To evaluate the effect of tannins, the extract with the greatest effect was incubated with polyvinyl polypyrrolidone (PVPP). The EE (50 mg ml(-1)) inhibited 99.8% of egg hatching. After the addition of PVPP, the ovicidal effectiveness of EE was reduced to 91.9%. Using the HE and EA, inhibition of egg hatching was 15.3% and 32.2%, respectively. In the LEIA, 18.9% of L3 incubated with EE were exsheathed (p<0.01). The addition of PVPP to EE reversed the inhibitory effect on larval exsheathment. The percentage of exsheathment of L3 incubated with HE (99.6%) and EA (97.8%) did not differ from the control group (p>0.05). The results show that the effects of EE on eggs are not solely due to the tannins. However, these secondary metabolites are implicated in blocking the larval exsheathment. 相似文献
92.
Martins DA Engrola S Morais S Bandarra N Coutinho J Yúfera M Conceição LE 《Fish physiology and biochemistry》2011,37(4):733-743
An experiment was conducted in order to evaluate the effects of feeding frozen Artemia diets differing in arachidonic acid-to-eicosapentaenoic acid ratios (ARA/EPA) on growth, survival and stress coping ability
of Senegalese sole post-larvae (19–31 days after hatch). Two experimental diets presenting high (‘High’; 3.0) or low (‘Low’;
0.7) ARA/EPA ratios were tested under two rearing conditions: undisturbed (C) and stressed by a 2-min air exposure every two
days (S). Growth, survival and basal cortisol levels were similar between groups indicating that independently of dietary
ARA/EPA ratios, fish were able to cope with the repeated stress imposed. Also, cortisol levels at 3 h past air exposure were
determined in all groups at the end of the experiment. Among fish fed the ‘Low’ diet, C groups seemed to present a quicker
recovery from the acute stress (basal-like levels) than S groups. Repeated stress effects were not apparent in fish fed the
‘High’ diet and, relative to basal levels, twofold higher cortisol concentrations were detected at 3 h, in both C and S groups.
This study suggests the importance of ARA in steroidogenesis regulation and the modulatory role of EPA in this process. Despite
the tolerance to a wide range of dietary ARA/EPA as indicated by growth and survival results, acute stress coping response
may be more efficient in Senegalese sole post-larvae fed low ARA/EPA ratios and, under these particular conditions, a faster
recovery of cortisol to basal values could be indicative of rearing conditions (undisturbed vs. repeatedly stressed). 相似文献
93.
J. Xavier U. Belini F. Pierron J. Morais J. Lousada M. Tomazello 《Wood Science and Technology》2013,47(2):423-441
This paper deals with the characterisation of bending stiffness components of medium density fibreboard (MDF) by carrying out a single plate bending test. The approach couples full-field slope measurements with an inverse identification method. MDF panels manufactured with different fractions of Eucalyptus fibres and sugarcane bagasse particles were used. The slope maps generated across the plate surface were measured by the deflectometry technique. The curvature fields of the deformed plate were reconstructed by numerical differentiation afterwards. The virtual fields method was then implemented for material parameter identification under the framework of Kirchhoff–Love plate bending theory. The elastic properties obtained from the proposed data reduction (i.e. simultaneous identification of modulus of elasticity, Poisson’s ratio and shear modulus) were compared with values determined from classical three-point bending tests and reported in the literature. The set of properties were found in relatively good agreement. 相似文献
94.
Tingting Zhu Sofia Morais Jiaxiang Luo Min Jin You Lu Yirong Le Qicun Zhou 《Journal of the World Aquaculture Society》2019,50(6):1064-1077
Squid visceral paste is a popular attractant and feeding stimulator supplement in shrimp feeds in China, but it often faces problems with fluctuating availability, cost, composition, and quality. An 8‐week experiment was performed to test a proprietary palatability enhancer as an alternative to squid paste in white shrimp feed. Seven diets were tested: a control diet with no supplementations; S1 and S3 diets supplemented with squid paste at 1 or 3%, respectively; S1+PE0.1 and S1+PE0.15 supplemented with both 1% squid paste and the palatability enhancer at either 0.1 or 0.15%, respectively; and finally PE0.1 and PE0.15 supplemented only with the palatability enhancer at 0.1 or 0.15%, respectively. The results showed a trend for increased feed intake and weight gain when squid paste was added to the diet compared to the control, but this was worsened by raising the inclusion level from 1 to 3%. The inclusion of the PE, in combination with squid paste or alone at 0.15%, led to a significantly higher growth, and a feeding stimulation effect was also indicated, with PE0.1 and PE0.15 having a higher feed intake than the control. A further beneficial effect was a significant increase in protease activity in the hepatopancreas in the S1+PE0.15, PE0.1, and PE0.15 treatments compared to the control. In addition, a significant increase in the height of the intestinal mucosal folds was observed in PE0.15, followed by PE0.1. The results demonstrated the potential to replace or reduce squid visceral paste in shrimp diets by supplementing with a PE with functional effects beyond feeding stimulation. 相似文献
95.
Dehaene S Pegado F Braga LW Ventura P Nunes Filho G Jobert A Dehaene-Lambertz G Kolinsky R Morais J Cohen L 《Science (New York, N.Y.)》2010,330(6009):1359-1364
Does literacy improve brain function? Does it also entail losses? Using functional magnetic resonance imaging, we measured brain responses to spoken and written language, visual faces, houses, tools, and checkers in adults of variable literacy (10 were illiterate, 22 became literate as adults, and 31 were literate in childhood). As literacy enhanced the left fusiform activation evoked by writing, it induced a small competition with faces at this location, but also broadly enhanced visual responses in fusiform and occipital cortex, extending to area V1. Literacy also enhanced phonological activation to speech in the planum temporale and afforded a top-down activation of orthography from spoken inputs. Most changes occurred even when literacy was acquired in adulthood, emphasizing that both childhood and adult education can profoundly refine cortical organization. 相似文献
96.
Is the onset of septoria tritici blotch epidemics related to the local pool of ascospores?
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To elucidate the early epidemic stages of septoria tritici blotch, especially the relationship between the onset of epidemics, the local availability of primary inoculum, and the presence of wheat debris, the early disease dynamics and airborne concentration in Zymoseptoria tritici ascospores were concomitantly assessed at a small spatiotemporal scale and over two years, using spore traps coupled with a qPCR assay. One plot, with the crop debris left, provided a local source of primary inoculum, while the other plot, without debris, lacked any. According to the assay's limits of detection, daily spore trap samples were classified as not detectable or not quantifiable, detectable, and quantifiable. The proportions of samples assigned to the different classes and numbers of spores in samples classified as quantifiable were significantly different between years, time periods (from November to March) and spore trap location (field with or without debris). The effect of year on the airborne ascospore concentration was high: 22 daily peaks with more than 230 ascospores m?3 day?1 were identified in the autumn of 2012/13, but none in the autumn of 2011/12. The local presence of wheat debris had no obvious effect on the amount of airborne ascospores or on the earliness of the two epidemics, especially in the year with high inoculum pressure (2012/13). These results suggest that the amount of primary airborne inoculum available in a wheat crop is not a limiting factor for the onset of an epidemic. 相似文献
97.
98.
Rabelo L Monteiro N Serquiz R Santos P Oliveira R Oliveira A Rocha H Morais AH Uchoa A Santos E 《Marine drugs》2012,10(4):727-743
Cancer represents a set of more than 100 diseases, including malignant tumors from different locations. Strategies inducing differentiation have had limited success in the treatment of established cancers. Marine sponges are a biological reservoir of bioactive molecules, especially lectins. Several animal and plant lectins were purified with antitumor activity, mitogenic, anti-inflammatory and antiviral, but there are few reports in the literature describing the mechanism of action of lectins purified from marine sponges to induce apoptosis in human tumor cells. In this work, a lectin purified from the marine sponge Cinachyrella apion (CaL) was evaluated with respect to its hemolytic, cytotoxic and antiproliferative properties, besides the ability to induce cell death in tumor cells. The antiproliferative activity of CaL was tested against HeLa, PC3 and 3T3 cell lines, with highest growth inhibition for HeLa, reducing cell growth at a dose dependent manner (0.5-10 μg/mL). Hemolytic activity and toxicity against peripheral blood cells were tested using the concentration of IC(50) (10 μg/mL) for both trials and twice the IC(50) for analysis in flow cytometry, indicating that CaL is not toxic to these cells. To assess the mechanism of cell death caused by CaL in HeLa cells, we performed flow cytometry and western blotting. Results showed that lectin probably induces cell death by apoptosis activation by pro-apoptotic protein Bax, promoting mitochondrial membrane permeabilization, cell cycle arrest in S phase and acting as both dependent and/or independent of caspases pathway. These results indicate the potential of CaL in studies of medicine for treating cancer. 相似文献
99.
Julimar do Sacramento Ribeiro Luana Lira Santos Dorgival Morais de Lima Júnior Tobyas Maia de Albuquerque Mariz Márcio Machado Ladeira Paulo Sérgio de Azevedo Carolyny Batista Lima Maria Josilaine Matos dos Santos Silva 《Tropical animal health and production》2017,49(5):995-1000
The effect of the replacement of corn silage with spineless cactus associated with Tifton 85 hay or sugarcane bagasse was evaluated on the performance, body weight components and sheep meat quality. Twenty-one Santa Inês male sheep with initial body weight of 22.9 ± 2.9 kg were used. They were confined in individual stalls for 74 days receiving the following diets: corn silage + concentrate (CS); spineless cactus + Tifton 85 hay + concentrate (TH); spineless cactus + sugarcane bagasse + concentrate (SB). After the feedlot period, the animals were slaughtered and their body components were weighed and sampled. Data were submitted to Tukey’s test at 5% probability. The average daily gain (0.25 vs 0.14 kg), cold carcass weight (13.3 vs 13.7 kg), loin muscularity (0.6 vs 0.4 kg) and liver weight (0.7 vs. 0.5 kg) were higher (P < 0.05) for the TH diet when compared to that for the CS. The physical-chemical parameters of meat were not influenced (P > 0.05) by the treatments and presented about 20.1% of crude protein, 6.1% of crude fat and shear force of 2.0 kgf/cm2. In complete diets for sheep, Tifton 85 hay associated with spineless cactus provides greater weight gain, cold carcass muscularity and organ weight when compared to those for animals fed with corn silage as exclusive roughage. Sugarcane bagasse associated with spineless cactus may replace corn silage in complete diets for sheep. 相似文献
100.