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951.
952.
Jucimara Baldissarelli Adriana Santi Roberta Schmatz Fátima Husein Abdalla Andréia Machado Cardoso Caroline Curry Martins Glaecir R. Mundstock Dias Nicéia Spanholi Calgaroto Luana Paula Pelinson Karine Paula Reichert Vania Lucia Loro Vera Maria Melchiors Morsch Maria Rosa Chitolina Schetinger 《Cellular and molecular neurobiology》2017,37(1):53-63
Thyroid hormones have an influence on the functioning of the central nervous system. Furthermore, the cholinergic and purinergic systems also are extensively involved in brain function. In this context, quercetin is a polyphenol with antioxidant and neuroprotective properties. This study investigated the effects of (MMI)-induced hypothyroidism on the NTPDase, 5′-nucleotidase, adenosine deaminase (ADA), and acetylcholinesterase (AChE) activities in synaptosomes of rats and whether the quercetin can prevent it. MMI at a concentration of 20 mg/100 mL was administered for 90 days in the drinking water. The animals were divided into six groups: control/water (CT/W), control/quercetin 10 mg/kg, control/quercetin 25 mg/kg, methimazole/water (MMI/W), methimazole/quercetin 10 mg/kg (MMI/Q10), and methimazole/quercetin 25 mg/kg (MMI/Q25). On the 30th day, hormonal dosing was performed to confirm hypothyroidism, and the animals were subsequently treated with 10 or 25 mg/kg quercetin for 60 days. NTPDase activity was not altered in the MMI/W group. However, treatment with quercetin decreased ATP and ADP hydrolysis in the MMI/Q10 and MMI/Q25 groups. 5′-nucleotidase activity increased in the MMI/W group, but treatments with 10 or 25 mg/kg quercetin decreased 5′-nucleotidase activity. ADA activity decreased in the CT/25 and MMI/Q25 groups. Furthermore, AChE activity was reduced in all groups with hypothyroidism. In vitro tests also demonstrated that quercetin per se decreased NTPDase, 5′-nucleotidase, and AChE activities. This study demonstrated changes in the 5′-nucleotidase and AChE activities indicating that purinergic and cholinergic neurotransmission are altered in this condition. In addition, quercetin can alter these parameters and may be a promising natural compound with important neuroprotective actions in hypothyroidism. 相似文献
953.
Franciane Cedrola Marta D'Agosto Roberto Júnio Pedroso Dias 《The Journal of eukaryotic microbiology》2017,64(2):242-247
The validity of genus Eodinium has been historically disputed due to morphological similarities with Diplodinium (absence of skeletal plates as well as adoral and dorsal ciliary zones at the same body level). To address this issue, the 18S rDNA of four Eodinium posterovesiculatum morphotypes and four Diplodinium anisacanthum morphotypes were sequenced and phylogenetically analyzed. The different inference methods suggest the existence of a last common ancestor of Eodinium and Ostracodinium that is not shared with Diplodinium, strongly supporting the validity of genus Eodinium. Since skeletal plates are present in all members of genus Ostracodinium, the most parsimonious is a secondary loss of skeletal plates in E. posterovesiculatum. This work represents a breakthrough in the taxonomy and phylogeny of the family Ophryoscolecidae indicating that the skeletal plates may not reflect evolutionary divergence within this group of ciliates as traditionally proposed. 相似文献
954.
Alternative products for Pratylenchus brachyurus and Meloidogyne javanica management in soya bean plants
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Angélica Miamoto Monique Thiara Rodrigues e Silva Claudia Regina Dias‐Arieira Heriksen Higashi Puerari 《Journal of Phytopathology》2017,165(10):635-640
Nematodes stand out among the main soya bean yield limiting factors due to limitations in the main control methods, mainly when they are applied alone. Given the need of finding new control techniques, the aim of this study was to assess the efficiency of products based on biological control agents and on nutrients or products showing potential to induce resistance for Pratylenchus brachyurus and Meloidogyne javanica control in soya bean plants. The experiments were conducted in a greenhouse; nine treatments with six repetitions for each nematode were assessed in two distinct periods. Overall, all treatments have shown potential to control the nematodes in at least one experiment, mainly the ones containing biological control agents (Trichoderma and Bacillus). The vegetative development results were inconclusive; however, some products have shown potential to improve the growth of infected plants. 相似文献
955.
Marília I. S. Folegatti Matsuura Fernando R. T. Dias Juliana F. Picoli Kássio R. Garcia Lucas Cesar de Castro Marcelo H. Hirakuri 《The International Journal of Life Cycle Assessment》2017,22(4):492-501
Purpose
In the “Cerrado” (Brazilian savanna), sunflower comes mostly from a cropping system where its seeding follows soybean harvest. Soybean has a much higher economic value, but this association with sunflower reduces the environmental impacts from both crops by sharing resources. This study performed a life-cycle assessment (LCA) of the soybean-sunflower cropping system, identified its hotspots, and compared its environmental performance with two hypothetical monocultures, in order to corroborate its benefits.Methods
Soybean-sunflower cropping system inventory used data from farms of the Parecis region, consolidated by experts. Inventories for soybean and sunflower monocultures were estimated from the cropping system inventory. LUC (land-use changes) were calculated from CONAB (2015), FAOSTAT (2012), and Macedo et al. (P Natl Acad Sci USA 109:1341–1346, 2012). Emissions estimation followed Nemecek and Schnetzer (2011), Milà i Canals (2003), and EC (2010). Land occupation, land-use changes, and liming were allocated by occupation time, but a sensitivity analysis was performed for yield and gross margin as allocation criteria. ReCiPe Midpoint (H) v1.12/World ReCiPe H was the impact assessment method, and some categories were disregarded as not relevant. We used pedigree matrix to estimate uncertainties for inventory and Monte Carlo method for impact uncertainty analysis as in Goedkoop et al. (2008). We used SimaPro 8.0.5.13.Results and discussion
The soybean-sunflower cropping system generate relevant human toxicity, freshwater toxicity, freshwater eutrophication, climate change, and terrestrial acidification impacts, related to emissions derived from nitrogen and phosphate fertilizers and emissions generated by LUC. Sunflower-soybean cropping system has better environmental performance when compared to the combination of monocultures because of a number of synergies made possible by sharing land use and other resources. Changing the allocation criteria altered the relative performance of some categories, but in all categories the environmental impacts of the cropping system were lower than those of the corresponding monoculture impacts, regardless of the allocation criteria implemented.Conclusions
We concluded that the environmental performance of the soybean-sunflower cropping system can be improved by optimizing the use of chemical fertilizers. Climate change impacts, which are mostly driven by LUC, could be reduced by production intensification, preventing the clearing of native vegetation for agricultural purposes. This study confirmed the environmental benefits of cropping systems when compared to monocultures and the advantages of association of nitrogen-fixing legumes with other plant species in a production system.956.
John Shuey Paul Labus Eduardo Carneiro Fernando Maia Silva Dias Luis Anderson R. Leite Olaf H. H. Mielke 《Journal of Insect Conservation》2017,21(3):545-557
The Atlantic forest is one of the most diverse biomes on Earth but human activities are transforming this ecosystem into one of the most endangered. Most remnant old-growth rainforest is embedded within a mosaic of regenerating forest, tree plantations, pastures, and agricultural production. This has left a large percentage of the region’s endemic species threatened with extinction. Butterflies are considered as sensitive indicators of ecological conditions, especially in the Atlantic forest. This community can provide a window into animal response to restoration and how recovering habitats are used by native animal communities. The primary goal of this paper was to determine if butterfly communities respond to measures of structural recovery in naturally regenerating and re-forested pastures, and if this response increases the similarity of recovering butterfly communities relative to those of intact forests. Butterfly communities were sampled using two sampling methodologies, passive bait trapping and timed meander counts. These data sets were combined and correlated to assessment of habitat structure. We found that butterfly communities respond rapidly to structural changes in habitats as forest structure recovers on abandoned and restored pastures. While many species of mature forest inhabiting butterflies use regenerating forests as habitat, our young forests also retained an almost intact community of ruderal pasture inhabiting butterflies as well, indicating that these habitats retain many features of highly disturbed pastures. We suggest that measures of beta-diversity, which can be used to assess convergence in community structure, are far superior to the alpha-diversity measures that are typically used for assessing restoration recovery. 相似文献
957.
Evelyn Jardim Oliveira Andréa Dias Koehler Diego Ismael Rocha Lorena Melo Vieira Marcos Vinícius Marques Pinheiro Elyabe Monteiro de Matos Ana Claudia Ferreira da Cruz Thais Cristina Ribeiro da Silva Francisco André Ossamu Tanaka Fabio Tebaldi Silveira Nogueira Wagner Campos Otoni 《Protoplasma》2017,254(5):2017-2034
958.
959.
Danucalov MA Simões RS Kozasa EH Leite JR 《Applied psychophysiology and biofeedback》2008,33(2):77-81
The novelty of this study was to investigate the changes in cardiorespiratory and metabolic intensity brought about by the practice of pranayamas (breathing exercises of yoga) and meditation during the same hatha-yoga session. The technique applied was the one advocated by the hatha-yoga system. Nine yoga instructors-five females and four males, mean age of 44+/-11, 6, were subjected to analysis of the gases expired during three distinct periods of 30 min: rest, respiratory exercises and meditative practice. A metabolic open circuit computerized system was applied (VO2000, MedGraphics-USA). The oxygen uptake (VO(2)) and the carbon dioxide output (VCO(2)) were statistically different (P 相似文献
960.
Simultaneous inhibition of the retrotrapezoid nucleus (RTN) and raphe obscurus (ROb) decreased the systemic CO(2) response by 51%, an effect greater than inhibition of RTN (-24%) or ROb (0%) alone, suggesting that ROb modulates chemoreception by interaction with the RTN (19). We investigated this interaction further by simultaneous dialysis of artificial cerebrospinal fluid equilibrated with 25% CO(2) in two probes located in or adjacent to the RTN and ROb in conscious adult male rats. Ventilation was measured in a whole body plethysmograph at 30 degrees C. There were four groups (n = 5): 1) probes correctly placed in both RTN and ROb (RTN-ROb); 2) one probe correctly placed in RTN and one incorrectly placed in areas adjacent to ROb (RTN-peri-ROb); 3) one probe correctly placed in ROb and one probe incorrectly placed in areas adjacent to RTN (peri-RTN-ROb); and 4) neither probe correctly placed (peri-RTN-peri-ROb). Focal simultaneous acidification of RTN-ROb significantly increased ventilation (Ve) up to 22% compared with baseline, with significant increases in both breathing frequency and tidal volume. Focal acidification of RTN-peri-ROb increased Ve significantly by up to 15% compared with baseline. Focal acidification of ROb and peri-RTN had no significant effect. The simultaneous acidification of regions just outside the RTN and ROb actually decreased Ve by up to 11%. These results support a modulatory role for the ROb with respect to central chemoreception at the RTN. 相似文献